DESCRIPTION
METHOD FOR MANUFACTURING MEMBER HAVING IRREGULAR PATTERN
TECHNICAL FIELD
[0001] The present invention relates to a method for manufacturing a member having an
irregular pattern (concave-convex pattern, concave and convex pattern).
BACKGROUND ART
[0002] As a method for forming a fine convex-concave pattern (minute convex-concave
pattern), such as a semiconductor integrated circuit, nanoimprint methods as well as
lithography methods are known. The nanoimprint method is technology capable of
transferring a pattern in nanometer order from a mold (die) to a substrate by sandwiching a
resin between the mold and the substrate. A thermal nanoimprint method, a
photonanoimprint method, or the like is used depending on an employed material. Of the
above methods, the photonanoimprint method includes four steps of: i) forming a curable
resin coating layer; ii) pressing with the mold against the curable resin layer; iii) photocuring
ofthe curable resin layer; and iv) mold-releasing from the curable resin layer. The
photonanoimprint method is excellent in that processing on a nanoscale can be achieved by
such a simple process. Especially, since a photo-curable resin curable by being irradiated
with light is used, a period of time for a pattern transfer step is short and high throughput is
promised. Thus, the photonanoimprint method is expected to be practiced not only in the
field of semiconductor devices but also in many fields, such as optical members like
organic EL (electro-luminescence) element, LED, etc.; MEMS; biochips; and the like.
[0003] For example, in the organic EL element (organic light emitting diode), a hole
injected from an anode through a hole injecting layer and electron injected from a cathode
through an electron injecting layer are carried to a light emitting layer respectively, then
the hole and electron are recombined on an organic molecule in the light emitting layer to
excite the organic molecule, thereby generating light emission. Therefore, when the
organic EL element is used as a display device and/or an illumination device, the light
from the light emitting layer is required to be efficiently extracted from the surface of the
2
organic EL element. In order to meet this demand, PATENT LITERATURE I discloses
that a substrate having a fine concave-convex pattern that serves as a diffraction grating is
provided on a light extraction surface of the organic EL element.
[0004] As a base member of the organic EL element, a film base member such as a film
base member which is formed of a resin, which is light and flexible, and can be produced
in a large size, has started to be adopted, in place of a glass substrate that is heavy, easily
broken, and hard to be produced in a large size. Unfortunately, the film base member such
as resin has a gas barrier property inferior to that of the glass substrate. In the organic EL
element, any moisture and/or oxygen might reduce luminance, light emitting efficiency,
and the like. Thus, when a resin-film base member is used as the base member of the
organic EL element, a gas barrier layer is required to be formed on the resin-film base
member to prevent any deterioration caused by moisture and/or gas including oxygen. For
example, PATENT LITERATURES 2 and 3 describe that a gas barrier layer formed by an
inorganic film is formed through a sputtering method, a vacuum evaporation method, an
ion plating method, a plasma CVD method, or the like.
[Citation List]
[Patent Literature]
[0005] PATENT LITERATURE I: Japanese Patent Application Laid-open No. 2006-
236748
PATENT LITERATURE 2: Japanese Patent Application Laid-open No. 20III02042
PATENT LITERATURE 3: Japanese Patent Application Laid-open No. 20 I3-
2533I9
SUMMARY OF INVENTION
Problem to be Solved by the Invention:
[0006] As described above, it is required to extract light from the organic EL element at
high efficiency by providing the substrate with the concave-convex pattern in the organic
EL element. Further, it is required to achieve a long service life of the organic EL element
by providing a layer with a good gas barrier property in. the organic EL element. In order
to meet these demands, forming a concave-convex pattern in a surface of the gas barrier
layer is favorable in view of production efficiency. Unfortunately, an inorganic film
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formed by a dry process, such as sputtering, is hard, and thus there is a problem that the
concave-convex pattern can not be formed on a surface ofthe inorganic film through
conventional nanoimprint methods.
[0007] An object of the present invention is to provide a method for manufacturing a
functional member with a functional layer, such as a gas barrier layer having a surface in
which a concave-convex pattern is formed. Another object of the present invention is to
provide a method for manufacturing a member with a film that is formed by a dry process
and has a surface in which a concave-convex pattern is formed.
Solution to the Problem:
[0008] According to the first aspect of the present invention, there is provided a method
for manufacturing a member with a concave-convex pattern, including: a step of forming a
first film on a concave-convex pattern formed on a surface of a mold; a step of forming a
second film on a base member; a step of joining the first film and the second film by
overlapping the mold with the base member (overlaying the mold on the base member);
and a step of releasing the mold from the first film joined to the second film.
[0009] The method for manufacturing the member with the concave-convex pattern may
further include a step of applying adhesive on the first film formed on the mold or the
second film formed on the base member before the joining step.
[0010] The method for manufacturing the member with the concave-convex pattern may
further include a step of forming, on the first film formed on the mold, a film different
from the first film and/or a step of forming, on the second film formed on the base member,
a film different from the second film, before the joining step.
[0011] According to the second aspect of the present invention, there is provided a
method for manufacturing a member with a concave-convex pattern, including: a step of
forming a first film, through a dry process, on a concave-convex pattern formed on a
surface of a mold; a step of joining a base member to the first film formed on the mold;
and a step of releasing the mold from the first film.
[0012] The method for manufacturing the member with the concave-convex pattern may
further include a step of applying adhesive on a surface, of the base member, which is to be
joined to the first film formed on the mold, or on the first film formed on the mold before
the joining step.
[0013] The method for manufacturing the member with the concave-convex pattern may
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further include a step of forming a film different from the first film, through the dry
process and/or a wet process, on the first film formed on the concave-convex pattern of the
mold.
[0014] In the first film formation step of the method for manufacturing the member with
the concave-convex pattern, the first film may be formed by depositing silicon oxide,
silicon oxynitride, or silicon nitride through the dry process.
[0015] The method for manufacturing the member with the concave-convex pattern may
include a step of forming a second film on the base member before the joining step.
[0016] In the method for manufacturing the member with the concave-convex pattern, the
first film and/or the second film may have a water vapor transmission rate of not more than
1 o-2 g·m-2·dai1
•
[0017] In the method for manufacturing the member with the concave-convex pattern, a
first gas barrier layer formed by the first film and the film which is formed on the first film
and different from the first film and/or a second gas barrier layer formed by the second
film and the film which is formed on the second film and different from the second film
may have a water vapor transmission rate of not more than 10-2 g·m-2·dai1
•
[0018] In the method for manufacturing the member with the concave-convex pattern, (i)
each of a plurality of convexities and each of a plurality of concavities of the concaveconvex
pattern of the mold may have an elongated shape which extends while winding in a
plane view; and (ii) the plurality of convexities may have extending directions, bending
directions and lengths which are non-uniform among the plurality of convexities, and the
plurality of concavities may have extending directions, bending directions and lengths
which are non-uniform among the plurality of concavities.
[0019] In the method for manufacturing the member with the concave-convex pattern, the
concave-convex pattern of the mold may be an irregular concave-convex pattern in which
an average pitch of concavities and convexities is in a range of 100 to 1500 nm and an
average value of depth distribution of the concavities and convexities is in a range of 20 to
200 nm.
[0020] In the method for manufacturing the member with the concave-convex pattern, a
Fourier-transformed image of a concavity and convexity analysis image of the mold may
show a circular or annular pattern substantially centered at an origin at which an absolute
value of wavenumber is 0 ).lm- 1
, and the circular or annular pattern may be present within a
region where the absolute value of wavenumber is in a range of not more than 10 ).lm- 1
•
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[0021] According to the third aspect of the present invention, there is provided a member
with a concave-convex pattern manufactured by the method for manufacturing the member
with the concave-convex pattern as defined in the first aspect or the second aspect.
[0022] The member with the concave-convex pattern may include a gas barrier layer, and
the first film may be included in the gas barrier layer.
[0023] In the member with the concave-convex pattern, the gas barrier layer may have a
water vapor transmission rate of not more than 10-2 g·m-2·dai1
•
[0024] According to the fourth aspect of the present invention, there is provided
an organic light emitting diode formed by successively stacking, on the member with the
concave-convex pattern as defined in the third aspect, a first electrode, an organic layer,
and a metal electrode.
EFFECT OF INVENTION
[0025] In the method for manufacturing the member with the concave-convex pattern
(concave-convex structure) according to the first aspect of the present invention, the first
film (first functional layer) is formed on the concave-convex pattern of the mold, the
second film (second functional layer) is formed on the base member, and the first film and
the second film are joined by overlapping the mold with the base member. Thus, there is
little restriction on the materials and coating methods for the first film and the second film
and it is possible to manufacture a functional member having a good function. In the
method for manufacturing the member with the concave-convex pattern according to the
second aspect of the present invention, the concave-convex pattern is formed directly on
the surface of the first film formed by the dry process, resulting in high production
efficiency. Each of the methods according to the first and second aspects forms the
member with the concave-convex pattern by transfer of the concave-convex pattern of the
mold, without using photolithography that causes a large amount of waste liquid, thus
resulting in being environmentally friendly. The manufacturing method according to the
present invention can manufacture the gas barrier member with the concave-convex pattern
by forming the film(s) having the gas barrier property, as the first film and/or the second
film. In particular, when the first film is formed by the dry process, the gas barrier layer
including the first film has a very good gas barrier property. The gas barrier member
having such a gas barrier layer has the concave-convex pattern, thus providing high light
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extraction efficiency. Therefore, a light emitting element manufactured by using this
member has a sufficient light-emitting efficiency and a long service life due to the
suppression of the deterioration caused by moisture and/or gas such as oxygen.
Accordingly, the method for manufacturing the member with the concave-convex pattern
according to the present invention is effective in manufacture of the gas barrier member
used for various devices, such as organic EL elements and solar cells. Further, the gas
barrier member manufactured by the manufacturing method according to the present
invention is suitably used for packaging applications, such as packaging of goods and
packaging for preventing any deterioration of foods, industrial goods, medical products,
and the like.
BRIEF DESCRIPTION OF DRAWINGS
[0026] Fig. 1 (a) is a schematic cross-sectional view of a member obtained by a method
for manufacturing a member with a concave-convex pattern according to a first
embodiment, and Fig. 1 (b) is a schematic cross-sectional view of a member obtained by a
method for manufacturing a member with a concave-convex pattern according to a first
modified embodiment.
Fig. 2(a) is a schematic plan view of the concave-convex pattern of the member
obtained by the manufacturing method ofthe first embodiment, and Fig. 2(b) is a crosssection
profile taken along the cutting-plane line in Fig. 2(a).
Fig. 3 depicts an exemplary Fourier-transformed image of a concavity and
convexity analysis image of a surface of a first film.
Fig. 4 is a flowchart indicating the method for manufacturing the member with the
concave-convex pattern according to the first embodiment.
Figs. 5(a) to 5(d) conceptually depict steps of the method for manufacturing the
member with the concave-convex pattern according to the first embodiment.
Fig. 6(a) conceptually depicts an exemplary first film formation step, joining step,
and releasing step in the manufacturing method ofthe first embodiment, and Fig. 6(b)
conceptually depicts an exemplary adhesive applying step, joining step, and releasing step
in the manufacturing method of the first modified embodiment.
Fig. 7 conceptually depicts a sputtering apparatus that can be used to form the first
film or a second film on a film-shaped mold or film-shaped base member.
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Fig. 8(a) is a schematic cross-sectional view of a member obtained by a method
for manufacturing a member with a concave-convex pattern according to a second
embodiment, and Fig. 8(b) is a schematic cross-sectional view of a member obtained by a
method for manufacturing a member with a concave-convex pattern according to a fourth
modified embodiment.
Fig. 9 is a flowchart indicating the method for manufacturing the member with the
concave-convex pattern according to the second embodiment.
Figs. I 0( a) to I 0( d) conceptually depict steps of the method for manufacturing the
member with the concave-convex pattern according to the second embodiment.
Fig. II (a) conceptually depicts an exemplary adhesive applying step, joining step,
and releasing step in the manufacturing method of the second embodiment, and Fig. II (b)
conceptually depicts an exemplary adhesive applying step, joining step, and releasing step
in the manufacturing method ofthe fourth modified embodiment.
Fig. I2(a) conceptually depicts a cross-sectional structure of a light emitting
element that is formed by using a gas barrier member manufactured through the method of
the first embodiment, and Fig. I2(b) conceptually depicts a cross-sectional structure of a
light emitting element that is formed by using a gas barrier member manufactured through
the method of the first modified embodiment.
Fig. I3(a) conceptually depicts a cross-sectional structure of a light emitting
element that is formed by using a gas barrier member manufactured through the method of
the second embodiment, and Fig. 13(b) conceptually depicts a cross-sectional structure of a
light emitting element that is formed by using a gas barrier member manufactured through
the method of the fourth modified embodiment.
DESCRIPTION OF EMBODIMENTS
[0027] In the following, embodiments of a member with a concave-convex structure
(concave-convex pattern), a method for manufacturing the member with the concaveconvex
structure, and a light emitting element manufactured by using the member with the
concave-convex structure according to the present invention will be explained with
reference to the drawings. The following describes, in the first embodiment of the present
invention, a case in which a gas barrier member is manufactured by forming films having a
gas barrier property as a first film (first functional layer) and a second film (second
8
functional layer) and describes, in the second embodiment of the present invention, a case
in which a gas barrier member is manufactured by forming a film having a gas barrier
property as the first film (first functional layer). As described later, the first film and/or the
second film is/are not limited to the film having the gas barrier property. The first film
and/or the second film may be a film having various functions so as to manufacture a
member with various functions. The manufactured member is applicable not only to the
light emitting element but also to a variety of uses.
[0028] [First gas barrier member]
As depicted in Fig. l(a), in a gas barrier member 100 with a concave-convex
structure (concave-convex pattern) 80 obtained in the first embodiment of the method for
manufacturing the gas barrier member with the concave-convex pattern as described later,
a second film 70 (second gas barrier layer) and a first film 60 (first gas barrier layer) are
formed on a base member 40 in that order. As depicted in Fig. 1 (b), in a gas barrier
member 1 OOa obtained in the first modified embodiment of the method for manufacturing
the gas barrier member with the concave-convex pattern as described later, the second film
70 is formed on the base member 40 and the first film 60 is formed on the second film 70
via an adhesive layer 30.
[0029]
The base member 40 is not especially limited, it is possible to appropriately use
any publicly known transparent substrate which can be used for the light emitting element.
The base member 40 may be a hard substrate or a flexible film-shaped substrate. For
example, it is possible to use substrates made from transparent inorganic materials, such as
glass, and substrates made from resins. Examples of substrates made from resins include
polyester (polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate,
polyarylate, and the like), an acrylic-based resin (polymethyl methacrylate and the like),
polycarbonate, polyvinyl chloride, a styrene-based resin (ABS resin and the like), a
cellulose-based resin (triacetyl cellulose and the like), a polyimide-based resin (polyimide
resin, polyimideamide resin, and the like) and cycloolefin polymer. When the gas barrier
member 100 is used as an optical substrate of the light emitting element, the base member
40 desirably has heat resistance and weather resistance to UV light and the like. In view of
those points, base members made from inorganic materials, such as glass and quarts
substrates, are more preferably used. In particular, when the first film 60 is made from the
inorganic material, the base member 40 is preferably made from the inorganic material.
9
This is because the difference between a refractive index of the base member 40 and a
refractive index of the first film 60 is small, which in turn makes it possible to prevent any
unintended refraction and/or reflection in the light emitting element when the gas barrier
member 100 is used as the optical substrate of the light emitting element. It is allowable to
perform a surface treatment for the base member 40 or to provide an easy-adhesion layer
on the base member 40 so as to improve the adhesion property of the base member 40
and/or it is allowable to provide a smoothing layer to cover any protrusion on a surface of
the base member 40. The thickness of the base member 40 is preferably in a range of 1 ).!ill
to 20 mm.
[0030]
The gas barrier member 100 includes the first film 60 that is formed as the first
gas barrier layer preventing permeation of oxygen and water vapor. The first film 60 may
be made from an inorganic material or an organic material (resin material). As the
inorganic material, inorganic oxide, inorganic nitride, inorganic oxynitride, inorganic
sulfide, inorganic carbide, or the like is preferably used; silicon oxide, aluminum oxide,
magnesium oxide, zinc oxide, indium oxide, tin oxide, titanic oxide, copper oxide, cerium
oxide, tantalum oxide, zirconium oxide, indium tin oxide, barium titanate, strontium
titanate, silicon nitride, silicon oxynitride, aluminum oxynitride, zinc sulfide, or the like is
more preferably used. Examples of the organic material include materials that may be
used as a sealing material of an organic EL element, such as XNR5516Z produced by
NAGASE & CO., LTD., TB3124 produced by THREEBOND HOLDINGS CO., LTD.,
and CEL VENUS HOO 1 produced by Daicel Corporation.
[0031] The first film 60 may be a film in which an ultraviolet absorbent material is
included in the inorganic material or the organic material. The ultraviolet absorbent
material has a function or effect to prevent deterioration of the film by absorbing
ultraviolet rays and converting light energy into something harmless such as heat. Any
publicly known agent may be used as the ultraviolet absorbent material. Those usable as
the ultraviolet absorbent material include, for example, benzotriazole-based absorbents,
triazine-based absorbents, salicylic acid derivative-based absorbents, benzophenone-based
absorbents, etc.
[0032] The first film 60 preferably has a water vapor transmission rate of not more than
1 o-2 g·m-2·dai1 to allow the gas barrier member 100 to have an enough gas barrier
property.
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[0033] The first film 60 preferably has a light transmission property. For example, the
first film 60 preferably has a transmittance of not less than 80% at a measurement
wavelength of 550 nm, more preferably has a transmittance of notless than 90% at the
measurement wavelength of 550 nm.
[0034] The thickness of the first film 60 is preferably in a range of 5 nm to 20 ~m. In this
context, the thickness of the first film 60 means an average value of distances from the
bottom surface of the first film 60 to the surface in which the concave-convex pattern 80 is
formed.
[0035] The surface of the first film 60 has the fine or minute concave-concave pattern
(concave-convex structure) 80. The fine concave-convex pattern 80 may be any pattern
such as a pattern having a lens structure, a structure having a light diffusion function or a
light diffraction, or the like. Fig. 2(a) is an exemplary schematic plan view of the concaveconvex
pattern 80 of the first film 60, and Fig. 2(b) is a cross-section profile taken along
the cutting-plane line in Fig. 2(a). As depicted in Fig. 2(b), the cross-sectional shape ofthe
first film 60 may be formed by relatively gentle inclined surfaces and may construct a
waveform (in the present application, referred to as "waveform structure" as appropriate)
upward from the base member 40. Namely, convexities of the concave-convex pattern 80
may have a cross-sectional shape which is narrowing from the base portion, of each
convexity, located on the side of the base member 40 toward the apex portion of each
convexity. The concave-convex pattern 80 of the first film 60 may have such a
characteristic that, as in Fig. 2(a) depicting an exemplary schematic plane view of the
concave-convex pattern 80, convexities (white portions) and concavities (black portions)
have an elongated shape extending while winding (waving, meandering), and that the
convexities and the concavities in the concave-convex pattern 80 have the extending
directions, winding direction (bending directions) and extending lengths which are
irregular in a plane view. Such a concave-convex pattern 80 is clearly different from a
regularly arranged pattern such as stripe, waved stripe, zigzag, etc., or a regularly arranged
pattern such as dot-shaped pattern, etc., and the concave-convex pattern 80 can be
distinguished, in view of this point, from a pattern, such as a circuit pattern, which has a
regularity and/or many linear portions or straight lines, etc. Since the first film 60 has the
above-described characteristics, when the first film 60 is cut in any plane perpendicular to
the surface of the base member 40, the concave-convex cross-section consequently appears
repeatedly. Further, a part (portion) or the entirety of convexities and the concavities of
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the concave-convex pattern 80 may be branched at an intermediate portion thereof, in a
plane view (see Fig. 2(a)). In Fig. 2(a), the pitch of the convexities appears to be uniform
as a whole. Further, in the concave-convex pattern 80, the concavities may be defined by
the convexities, and may extend along the convexities.
[0036] In addition to the irregular concave-convex pattern as described above, the
concave-convex pattern 80 may be any pattern having a dot structure; a prism structure; a
stripe structure formed by lines and spaces; a pillar structure formed by cylindrical shaped
structures, conical shaped structures, truncated cone shaped structures, triangle pole shaped
structures, triangular pyramid shaped structures, truncated triangular pyramid shaped
structures, square pole shaped structures, quadrangular pyramid shaped structures,
truncated quadrangular pyramid shaped structures, polygonal column shaped structures,
polygonal pyramid shaped structures, truncated polygonal pyramid shaped structures, or
the like; a hole structure; a micro lens array structure; or a structure having a function such
as light diffusion and/or diffraction. Further, the concave-convex pattern 80 may be an
irregular minute concave-convex pattern formed by a sandblasting method.
[0037] In order that the concave-convex pattern 80 of the first film 60 functions as the
diffraction grating, the average pitch of concavities and convexities is preferably in a range
of 100 to 1500 nm. When the average pitch of concavities and convexities is less than the
lower limit, pitches are so small relative to wavelengths of visible light that the diffraction
of light by concavities and convexities is less likely to occur. On the other hand, when the
average pitch exceeds the upper limit, the diffraction angle is so small that functions as the
diffraction grating are more likely to be lost. The average pitch of concavities and
convexities is more preferably in a range of200 to 1200 nm. The average value of the
. depth distribution of concavities and convexities is preferably in a range of 20 to 200 nm.
When the average value of the depth distribution of concavities and convexities is less than
the lower limit, the depth is so small relative to wavelengths of visible light that the
required diffraction is less likely to occur. On the other hand, when the average value of
the depth distribution of concavities and convexities exceeds the upper limit, intensity of
diffracted light is likely to become non-uniform, which in tum may lead to the following
situation when an organic EL element is produced by using the gas barrier member 100.
For example, an electric field distribution in an organic layer of the organic EL element
becomes non-uniform to cause the electric field to concentrate on a certain position or area
in the organic layer, thus causing any leak current to be easily generated, and/or shortening
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a service life of the organic EL element. The average value of the depth distribution of
concavities and convexities is more preferably in a range of 30 to 150 nm. The standard
deviation of the depth of convexities and concavities is preferably in a range of 10 to 100
nm. When the standard deviation of depth of convexities and concavities is less than the
lower limit, the depth is so small relative to wavelengths of visible light that the required
diffraction is less likely to occur. On the other hand, when the standard deviation of depth
of convexities and concavities exceeds the upper limit, intensity of diffracted light is likely
to become non-uniform, which in turn may lead to the following situation when an organic
EL element is produced by using the gas barrier member 100. For example, an electric
field distribution in an organic layer of the organic EL element becomes non-uniform to
cause the electric field to concentrate on a certain position or area in the organic layer, thus
causing any leak current to be easily generated, and/or shortening a service life of the
organic EL element. The standard deviation of depth of convexities and concavities is
more preferably in a range of 15 to 75 nm.
[0038] Note that the term "average pitch of concavities and convexities" in the present
application means an average value of the pitch of concavities and convexities in a case of
measuring the pitch of concavities and convexities (spacing distance between adjacent
convex portions or spacing distance between adjacent concave portions) in a surface on
which the convexities and concavities are formed. Such an average value of the pitch of
concavities and convexities can be obtained as follows. Namely, a concavity and
convexity analysis image is obtained by measuring the shape of concavities and
convexities on the surface by using a scanning probe microscope (for example, a scanning
probe microscope manufactured by Hitachi High-Tech Science Corporation, under the
product name of "E-sweep", etc.), under the following measurement conditions, then the
distances between randomly selected concave portions or convex portions adjacent to each
other are measured at not less than 1 00 points in the concavity and convexity analysis
image, and then the average of the distances is arithmetically calculated and is determined
as the average pitch of concavities and convexities. The measurement conditions are as
follows:
Measurement mode: cantilever intermittent contact mode
Material ofthe cantilever: silicon
Lever width of the cantilever: 40 f.Lm
Diameter of tip of chip of the cantilever: 1 0 nm
13
[0039] Further, in the present application, the average value of the depth distribution of
concavities and convexities and the standard deviation of the depth of concavities and
convexities can be calculated by the following manner. Namely, a concavity and
convexity analysis image is obtained by measuring the shape of concavities and
convexities on the surface by using a scanning probe microscope (for example, a scanning
probe microscope manufactured by Hitachi High-Tech Science Corporation, under the
product name of "E-sweep", etc.), in a randomly selected measurement region of 3 J.lm
square (vertical: 3 ).liD, horizontal: 3 ).lm) or in a randomly selected measurement region of
10 ).liD square (vertical: 10 ).lffi, horizontal: 10 ).lm) under the above-described conditions.
When doing so, data of height of concavities and convexities at not less than 16,3 84 points
(vertical: 128 points x horizontal: 128 points) are obtained within the measurement region,
each in nanometer scale. Note that although the number of measurement points is different
depending on the kind and setting of the measuring device which is used, for example in a
case of using the above-described scanning probe microscope manufactured by Hitachi
High-Tech Science Corporation, under the product name of "E-sweep'', it is possible to
perform the measurement at measurement points of 65,536 points (vertical: 256 points x
horizontal: 256 points; namely, the measurement in a resolution of256 x 256 pixels)
within the measurement region of 3 ).lffi square. With respect to the height of concavities
and convexities (unit: nm) measured in such a manner, at first, a measurement point "P" is
determined, among all the measurement points, which is the highest from the surface of a
base member. Then, a plane which includes the measurement point P and is parallel to the
surface of the base member is determined as a reference plane (horizontal plane), and a
depth value from the reference plane (difference obtained by subtracting, from the value of
height from the base member at the measurement point P, the height from the base member
at each of the measurement points) is obtained as the data of depth of concavities and
convexities. Note that such a depth data of concavities and convexities can be obtained,
for example, by performing automatic calculation with software in the measurement device
(for example, the above-described scanning probe microscope manufactured by Hitachi
High-Tech Science Corporation, under the product name of "E-sweep"), and the value
obtained by the automatic calculation in such a manner can be utilized as the data of depth
of concavities and convexities. After obtaining the data of depth of concavity and
convexity at each of the measurement points in this manner, the values, which can be
calculated by obtaining the arithmetic average value and the standard deviation of the
14
obtained data of depth of concavity and convexity, are adopted as the average value of the
depth distribution of concavities and convexities and the standard deviation of the depth of
concavities and convexities. In this specification, the average pitch of concavities and
convexities, the average value of the depth distribution of concavities and convexities, and
the standard deviation of depth of concavities and convexities can be obtained via the
above-described measuring method, regardless of the material of the surface on which
concavities and convexities are formed.
[0040] The concave-convex pattern 80 may be a such a quasi-periodic pattern in which a
Fourier-transformed image, obtained by performing a two-dimensional fast Fouriertransform
processing on a concavity and convexity analysis image obtained by analyzing a
concave-convex shape on the surface, shows a circular or annular pattern as depicted in Fig.
3, namely, such a quasi-periodic pattern in which, although concavities and convexities
have no particular orientation (directionality), the pattern has the distribution of pitches of
concavities and convexities (pitches of concavities and convexities vary). Therefore, a gas
barrier member having such a quasi-periodic pattern is suitable for a diffraction substrate
used in a surface-emitting element, such as the organic EL element, provided that the gas
barrier member has concavities and convexities of which pitch distribution or pitch
variability enables the gas barrier member to diffract visible light.
[0041] As depicted in Fig. 3, the Fourier-transformed image may show a circular or
annular pattern substantially centered at an origin at which an absolute value of
wavenumber is 0 J..Lm- 1
, and the circular or annular pattern may be present within a region
where the absolute value of wavenumber is in a range of not more than 10 J..Lm-1 (more
preferably in a range of 0.667 to 10 J..Lm- 1
, further preferably in a range of 0.833 to 5 J..Lm- 1
).
The circular pattern of the Fourier-transformed image is a pattern observed due to
gathering of bright spots in the Fourier-transformed image. The term "circular" herein
means that the pattern of the gathering of bright spots looks like a substantially circular
shape, and is a concept further including a case where a part of the contour ofthe circular
pattern looks like a convex shape or a concave shape. The pattern of the gathering of
bright spots may look like a substantially annular shape, and this case is expressed as the
term "annular". It is noted that the term "annular" is a concept further including a case
where a shape of an outer circle or inner circle of the ring looks like a substantially circular
shape and a case where a part of the contour of the outer circle or the inner circle of the
ring looks like a convex shape or a concave shape. Further, the phrase "the circular or
15
annular pattern is present within a region where the absolute value of wavenumber is not
more than I 0 ~--tm- 1 (more preferably in a range of 0.667 to I 0 ~--tm- 1 , further preferably in a
range of 0.833 to 5 ~--tm- 1 )" means that not less than 30% (more preferably not less than
50%, further preferably not less than 80%, and particularly preferably not less than 90%)
of bright spots forming the Fourier-transformed image are present within the region where
the absolute value of wavenumber is not more than IO ~--tm- 1 (more preferably in the range
of 0.667 to 10 ~--tm- 1 , and further preferably in the range of 0.833 to 5 ~--tm- 1 ). Regarding the
relationship between the concave-convex pattern and the Fourier-transformed image, the
followings have been revealed. Namely, when the concave-convex pattern itself has
neither the pitch distribution nor the directivity, the Fourier-transformed image appears to
have a random pattern (no pattern). On the other hand, when the concave-convex pattern
is entirely isotropic in an XY direction but has the pitch distribution, a circular or annular
Fourier-transformed image appears. Further, when the concave-convex pattern has a
single pitch, the annular shape appeared in the Fourier-transformed image tends to be sharp.
[0042] The two-dimensional fast Fourier transform processing on the concavity and
convexity analysis image can be easily performed by electronic image processing by using
a computer equipped with software for the two-dimensional fast Fourier transform
processing.
[0043] Although Fig. I (a) depicts a structure in which the first gas barrier layer is formed
only of the first film 60, that is, a structure in which the first gas barrier layer is formed by
the first film 60 as a single layer, the first gas barrier layer may be formed by a multilayer
film including the first film 60 and at least one film that is different from the first film 60
and disposed under the first film 60 (on a side, of the first film 60, facing the base member
40, namely a position between the first film 60 and the second film 70). The at least one
film different from the first film 60 and disposed under the first film 60 may be made from
an inorganic material, an organic material, or a material in which an ultraviolet absorbent
material is included in the inorganic material or the organic material, and examples of the
inorganic material and the organic material are the same as those listed as the materials that
may be used for the first film 60. A stress relaxation layer may be provided between
respective layers. Those usable for the stress relaxation layer include, for example, various
resins such as monomers, oligomers, and polymers ofthose based on epoxy, acrylic,
methacrylic, vinyl ether, oxetane, urethane, melamine, urea, polyester, polyolefin, phenol,
cross-linking type liquid crystal, fluorine, silicone, polyamide, etc.
16
[0044] When the gas barrier member, of which first gas barrier layer is formed as the
multilayer film, is used as an optical substrate of the light emitting element, the first gas
barrier layer preferably has a light transmission property. The first gas barrier layer
preferably has a transmittance of not less than 80% at a measurement wavelength of 550
nm, more preferably has a transmittance of not less than 90% at the measurement
wavelength of 550 nm.
[0045] When the first gas barrier layer is formed as the multilayer film, the thickness of
the first gas barrier layer is preferably in a range of 5 nm to 20 J.lm. In this context, the
thickness of the first gas barrier layer means an average value of distances from the bottom
surface of the first gas barrier layer to the surface in which the concave-convex pattern 80
is formed.
[0046] When the first gas barrier layer is formed as the multilayer film, the water vapor
transmission rate of the first gas barrier layer is preferably not more than 10-2 g·m-2·dai1 to
allow the gas barrier member 100 to have an enough gas barrier property. In that case, the
water vapor transmission rate of the first film may exceed 10-2 g·m-2·day-1
•
[0047]
In the gas barrier member 100, the second member 70 is formed, as the second gas
barrier layer, between the base member 40 and the first firm 60. As the material for the
second film 70, it is possible to use any of the inorganic materials and the organic materials
(resin materials) listed as the materials that may be used for the first film 60, and a material
in which an ultraviolet absorbent material is included in the inorganic material or the
organic material.
[0048] When the gas barrier member 100 is used as an optical substrate of the light
emitting element, the second film 70 preferably has a light transmission property. For
example, the second film 70 preferably has a transmittance of not less than 80% at a
measurement wavelength of 550 nm, more preferably has a transmittance of not less than
90% at the measurement wavelength of 550 nm.
[0049] The thickness of the second film 70 is preferably in a range of 5 nm to 20 J.lm.
[0050] Although Fig. 1 (a) depicts a structure in which the second gas barrier layer is
formed by the second film 70 as a single layer, the second gas barrier layer may be formed
by a multilayer film including the second film 70 and at least one film that is different from
the second film 70. The at least one film different from the second film 70 may be made
from any of those listed as the materials that may be used for the second film 70. A stress
17
relaxation layer may be provided between respective layers.
[0051] When the gas barrier member, of which second gas barrier layer is formed as the
multilayer film, is used as an optical substrate of the light emitting element, the second gas
barrier layer preferably has a light transmission property. The second gas barrier layer
preferably has a transmittance of not less than 80% at a measurement wavelength of 550
nm, more preferably has a transmittance of not less than 90% at the measurement
wavelength of 550 nm.
[0052] When the second gas barrier layer is formed as the multilayer film, the thickness
of the second gas barrier layer is preferably in a range of 5 nm to 20 )lm.
[0053] When the second gas barrier layer is formed as the multilayer film, the water
vapor transmission rate of the second gas barrier layer is preferably not more than 10-2
g·m-2·daf1 to allow the gas barrier member to have an enough gas barrier property. In that
case, the water vapor transmission rate of the second film may exceed 10-2 g·m-2·daf1
•
[0054]
The gas barrier member may be the gas barrier member 1 OOa as depicted in Fig.
1 (b) including the adhesive layer 30 between the first film 60 and the second film 70. That
is, the first film 60 and the second film 70 may be joined via the adhesive layer 30. The
thickness of the adhesive layer 30 is preferably in a range of 500 nm to 20 )lm.
[0055] As the material of the adhesive layer 30, it is allowable to use, without any
restriction, any adhesive which is generally used for glass or a plastic substrate, etc., and
which is exemplified, for example, by polyvinyl acetate-based adhesive; photo-curable and
thermo-curable acrylic-based adhesives having a reactive vinyl group such as acrylic acidbased
oligomer, methacrylic acid-based oligomer, etc.; epoxy resin adhesive; moisturecurable
adhesive such as 2-cyanoacrylic acid ester; ethylene copolymer-based adhesive;
polyester-based adhesive; polyimide-based adhesive; amino resin-based adhesive
composed of urea resin, melamine resin, or the like; phenolic resin-based adhesive;
polyurethane-based adhesive; reactive (meth)acrylic-based adhesive; rubber-based
adhesive; vinyl ether-based adhesive; silicone-based adhesive; etc. Among those
adhesives, preferable adhesives include the acrylic-based adhesive, the epoxy-based
adhesive, etc., among which the epoxy-based adhesive of which contraction (shrinkage)
during the curing is small is particularly preferable. When the gas barrier member 1 OOa is
used as an optical element of the organic EL element or the like, the adhesive layer 30 may
be made from any of the materials that may be used for the sealing material of the organic
18
EL element.
[0056] The epoxy-based adhesives include, for example, an epoxy resin composition
made from an epoxy resin and a curing agent. The adhesive force of the epoxy resin
composition is generated by its curing reaction which is brought about by mixing a
compound containing an epoxy group with the curing agent containing amines and acid
anhydride. The epoxy-based adhesives usable in the present embodiment are exemplified,
for example, by Cemedine EP-001 produced by CEMEDINE CO., LTD.; 3950, 3951 and
3952 of3950 series, 2083, 2086 and 2087 of2080 series, and 2230 and 22308 of2230
series, and 3124C produced by THREEBOND HOLDINGS CO., LTD.; MOS07 and
MOS 10 of Bond MOS series produced by KONISHI CO., LTD.; UL TIGHT 1540 and the
like of UL TIGHT 1500 series produced by TOHO KASEl CO., LTD.; and
XNR5576/5576LV, XNR5516/5516HV/5516Z, XNR5570, T470/UR7116, T470/UR7134,
T470/UR7132, and T470/UR7124E-LV produced by NAGASE CHEMTEX
CORPORATION; NOA81 produced by Norland Products Inc.; KR-508 produced by
ADECA CORPORATION; and CELVENUS-HBF series and CELVENUS-HRF series
produced by Daicel Corporation.
[0057] The acrylic-based adhesives include, for example, an adhesive containing an
acrylic-based pressure-sensitive adhesive component, an energy-ray curable component
and a thermo-curable adhesive component. The acrylic-based adhesives usable in the
present embodiment are exemplified, for example, by 3003, 30278, 30338, 30428, and the
like produced by THREEBOND HOLDINGS CO., LTD.; Cemedine Y600 and Cemedine
Y600H produced by CEMEDINE CO., LTD.; and WORLD ROCK No. 0555 and the like
produced by KYORITSU CHEMICAL & CO., LTD.
[0058] Other than the those listed above, the rubber-based adhesives include, for example,
one obtained in such a manner that adhesive elastomer, an adhesion-imparting agent, a
softening agent, and the like are mixed with one another. The adhesive elastomer is at
least one kind of adhesive elastomer selected, for example, from natural rubber composed
mainly of cis-1 ,4-polyisoprene; synthetic rubber composed mainly of styrene-butadiene
rubber (SBR), polyisobutylene, butyl rubber, and the like; and block rubber composed
mainly of styrene-butadiene-styrene copolymer rubber (SBS), styrene-isoprene-styrene
copolymer rubber (SIS), and the like. The adhesion-imparting agent is a thermoplastic
resin containing an amorphous oligomer (middle-molecular weight polymer of a dimer or
more), the amorphous oligomer being a liquid or solid at normal temperature and having a
19
molecular weight in a range of hundreds to about ten thousand, such as a rosin-based resin,
a terpene-based resin, a petroleum resin, and a chroman-indene resin. The softening agent
is exemplified, for example, by mineral oil, liquid polybutene, liquid polyisobutylene, and
liquid polyacrylic ester.
[0059] Examples of vinyl ether-based adhesives include an adhesive composed of a
homopolymer such as vinyl methyl ether, vinyl ethyl ether or vinyl isobutyl ether, an
adhesive composed of a copolymer of acrylate and vinyl ether such as vinyl methyl ether,
vinyl ethyl ether or vinyl isobutyl ether (adhesive elastomer), and the like. Each of the
above-described vinyl ether-based adhesives may be mixed with the above-described
adhesion-imparting agent, softening agent, or the like.
[0060] Examples of silicone-based adhesives include one obtained in such a manner that
a polymer (or adhesive elastomer) containing a residual silanol group (SiOH) at an end of a
polymer chain is mixed with the above-described adhesion-imparting agent, softening
agent, or the like. The polymer containing a residual silanol group is represented by
polydimethylsiloxane or polydimethyldiphenylsiloxane having high molecular weight.
[0061] For example, XNR5516Z produced by NAGASE & CO., LTD.; TB3124
produced by THREEBOND HOLDINGS CO., LTD.; CELVENUS H001 produced by
Daicel Corporation; or the like may be used as the material of the sealing material of the
organic EL element.
[0062] [First embodiment of method for manufacturing gas barrier member]
An explanation will be made about the first embodiment of the method for
manufacturing the gas barrier member. As indicated in Fig. 4, the method for
manufacturing the gas barrier member mainly includes a step S 1 for forming the first film
on a concave-convex pattern of a mold; a step S2 for forming the second film on the base
member; a step S3 for joining the first film and the second film; and a step S4 for releasing
the mold from the first film. In the following, the mold with the concave-convex pattern
and a method for manufacturing the mold will be explained first, and then the steps S 1 to
S4 will be explained in that order with reference to Figs. 5(a) to 5(d).
[0063]
The mold used in the method for manufacturing the gas barrier member according
to the first embodiment has the concave-convex pattern corresponding to the abovedescribed
concave-convex pattern of the first film (concave-convex pattern obtained by
inverting the concave-convex pattern of the first film). For example, the concave-convex
20
pattern ofthe mold may be a such a quasi-periodic pattern in which a Fourier-transformed
image, obtained by performing a two-dimensional fast Fourier-transform processing on a
concavity and convexity analysis image obtained by analyzing a concave-convex shape,
shows a circular or annular pattern, namely, such a quasi-periodic pattern in which,
although concavities and convexities have no particular orientation (directionality), the
pattern has the distribution of pitches of concavities and convexities (pitches of concavities
and convexities vary). The Fourier-transformed image may show a circular or annular
pattern substantially centered at an origin at which an absolute value of wavenumber is 0
!J.m- 1
, and that the circular or annular pattern may be present within a region where the
absolute value ofwavenumber is in a range of not more than 10 !J.m-1 (more preferably in a
range of 0.667 to 10 1-1m- 1
, further preferably in a range of 0.833 to 5 !J.m- 1
). Examples of
the mold having such a concave-convex pattern include a metal mold and a film-shaped
resin mold produced in a method as will be described later on. The resin forming the resin
mold includes rubber such as natural rubber or synthetic rubber.
[0064] An explanation will be given about an exemplary method for producing the mold.
A master block pattern for forming the concave-convex pattern of the mold is produced
first. For example, when a gas barrier member having a concave-convex pattern composed
of curved line-shaped convexities and concavities extending in non-uniform directions is
manufactured, it is suitable that the master block is formed by a method of utilizing the
self-organization or self-assembly (micro phase separation) of a block copolymer by
heating, as described in International Publication No. W02012/096368 ofthe applicants of
the present invention (hereinafter referred to as "BCP (Block Copolymer) thermal
annealing method" as appropriate), or a method of utilizing the self-organization or selfassembly
of a block copolymer under a solvent atmosphere, as described in International
Publication No. W02013/161454 ofthe applicants ofthe present invention (hereinafter
referred to as "BCP solvent annealing method" as appropriate), or a method of heating and
cooling a vapor deposited film on a polymer film to form concavities and convexities of
wrinkles on a surface of polymer, as disclosed in International Publication No.
W020 11/007878 A 1 of the applicants of the present invention (hereinafter referred to as
"BKL (Buckling) method" as appropriate). When the pattern is formed by the BCP
thermal annealing method or the BCP solvent annealing method, although any material can
be used as the material for forming the pattern, the material is preferably a block
copolymer composed of a combination of two selected from the group consisting of: a
21
styrene-based polymer such as polystyrene; polyalkyl methacrylate such as polymethyl
methacrylate; polyethylene oxide; polybutadiene; polyisoprene; polyvinylpyridine; and
polylactic acid. The pattern formed by the self-organization of these materials preferably
has a horizontal cylinder structure (structure wherein cylinders are oriented horizontally
relative to a base material) as described in W020 13/161454, or a vertical lamella structure
(structure in which lamellae are oriented vertically relative to a base material) as described
in "Macromolecules" 2014, Vol. 47, pp. 2, among which the vertical lamella structure is
more preferable for a case of forming deeper concavities and convexities. Further, the
concave-convex pattern obtained by the solvent annealing process may be subjected to
etching by irradiation with energy rays represented by ultraviolet rays such as excimer UV
light, or etching by a dry etching method such as RIE (reactive ion etching) or ICP etching.
Furthermore, the concave-convex pattern that has been subjected to such an etching may
be subjected to the heating process. Moreover, based on the concave-convex pattern
formed by the BCP thermal annealing method or the BCP solvent annealing method, it is
possible to form a concave-convex pattern in which concavities and convexities have
further deeper depth, with a method as described in "Advanced Materials" 2012, vol. 24,
pp. 5688-5694, "Science", vol. 322, pp. 429 (2008), etc. Namely, a base material layer
including Si02, Si, etc. is coated with a block copolymer, and a self-organization structure
of the block copolymer is formed by the BCP thermal annealing method or the BCP
solvent annealing method. Then, one of the segments of the block copolymer is selectively
etched away. The other segment, as the remaining segment, is used as a mask to perform
etching for the base material layer, thereby forming a groove (concavity or concave
portion) having a desired depth in the base material layer.
[0065] Instead of using the above-described BCP thermal annealing method, the BKL
method and the BCP solvent annealing method, the photolithography method may be used
to form the concave-convex pattern. Other than these, the concave-convex pattern of the
master block can be produced by any method including, for example, microfabrication or
fine-processing methods such as a cutting (cutting and processing) or machining method,
an electron-beam direct imaging method, a particle beam processing method, and a
scanning probe processing method; a fine-processing method using the self-organization or
self-assembly of fine particles; and a sandblasting method. In a case of manufacturing a
member (gas barrier member) with a concave-convex pattern composed of linear or
curved-shaped convexities and concavities extending in a uniform direction by use of the
22
mold, each of the above methods may be used to form a master block with the concaveconvex
pattern composed of the linear or curved-shaped convexities and concavities
extending in the uniform direction.
[0066] After forming the master block with the concave-convex pattern by means of the
BCP thermal annealing method, the BKL method or the BCP solvent annealing method,
etc., further, a mold to which the pattern is transferred can be formed by an electroforming
method or the like, as follows. At first, a seed layer functioning as an electroconductive
layer for an electroforming process can be formed on the master block, which has the
pattern thereon, by means of non-electrolytic plating, sputtering, vapor deposition, or the
like. The thickness of the seed layer is preferably not less than 10 nm to uniformize a
current density during the subsequent electroforming process, and thereby making the
thickness of a metal layer accumulated by the subsequent electroforming process be
uniform. As the material of the seed layer, it is possible to use, for example, nickel, copper,
gold, silver, platinum, titanium, cobalt, tin, zinc, chrome, gold-cobalt alloy, gold-nickel
alloy, boron-nickel alloy, solder, copper-nickel-chromium alloy, tin-nickel alloy, nickelpalladium
alloy, nickel-cobalt-phosphorus alloy, or alloy thereof. Subsequently, a metal
layer is accumulated on the seed layer by the electroforming (electroplating). The entire
thickness of the metal layer including the thickness of the seed layer can be, for example,
in a range of 10 f!m to 30,000 f!m. As the material of the metal layer accumulated by the
electroforming, it is possible to use any of the metal species as described above which can
be used as the seed layer. Considering ease of the subsequent processes for forming the
mold such as pressing with respect to the resin layer, releasing (peeling-off), and cleaning
(washing), the formed metal layer desirably has appropriate hardness and thickness.
[0067] The metal layer including the seed layer obtained as described above is released
(peeled off) from the master block having the concave-convex structure to obtain a metal
substrate. The metal substrate may be peeled off from the master block physically.
Alternatively, the materials composing the pattern of the master block may be dissolved to
be removed by using an organic solvent dissolving them, such as toluene, tetrahydrofuran
(THF), and chloroform, such that the metal substrate can be peeled off from the master
block. When the metal substrate is peeled off from the master block, a remaining material
component on the metal substrate can be removed by cleaning. As the cleaning method, it
is possible to use wet cleaning using a surfactant etc., or dry cleaning using ultraviolet rays
and/or plasma. Alternatively, for example, it is allowable to use an adhesive agent or a
23
bonding agent such that the remaining material component is caused to attach or adhere to
the adhesive agent or the bonding agent then is removed. Accordingly, the metal substrate
(metal mold) which can be obtained in such a manner and to which the pattern has been
transferred from the master block may be used as the mold for concave-convex pattern
transfer of the present embodiment.
[0068] Further, a flexible mold such as a film-shaped mold can be produced by using the
obtained metal substrate and by transferring the concave-convex structure (pattern) of the
obtained metal substrate to a film-shaped supporting substrate. For example, after the
supporting substrate is coated with the curable resin to form a resin layer, the resin layer is
cured while the concave-convex structure of the metal substrate is being pressed against
the resin layer. The supporting substrate is exemplified, for example, by base members
made from inorganic materials such as glass, quartz (quartz glass), silicon, etc.; base
members made from organic materials such as silicone resin, polyethylene terephthalate
(PET), polyethylene naphthalate (PEN), polycarbonate (PC), cycloolefin polymer (COP),
polymethyl methacrylate (PMMA), polystyrene (PS), polyimide (PI), polyarylate, etc.; and
metallic materials such as nickel, copper, aluminum, etc. The thickness of the supporting
substrate may be in a range of I f.!m to 500 f.!m.
[0069] The curable resin can be exemplified by various resins including, for example,
monomers, oligomers, and polymers of those based on epoxy, aery!, methacryl, vinyl ether,
oxetane, urethane, melamine, urea, polyester, polyolefin, phenol, cross-linking type liquid
crystal, fluorine, silicone, polyamide, etc. The thickness of the curable resin is preferably
in a range of 0.5 f.!m to 500 f.!m. When the thickness is less than the lower limit, heights of
the concavities and convexities formed on the surface of the cured resin layer are likely to
be insufficient. On the other hand, when the thickness exceeds the upper limit, the
influence of volume change of the resin upon curing is likely to be so large that there is
such a possibility that the formation of the shape of the concavities and convexities might
be unsatisfactory.
[0070] As a method for coating the supporting substrate with the curable resin, it is
possible to adopt, for example, various coating methods such as the spin coating method,
spray coating method, dip coating method, dropping method, gravure printing method,
screen printing method, relief printing method, die coating method, curtain coating method,
ink-jet method, and sputtering method. Further, although the condition for curing the
curable resin varies depending on the kind of the resin to be used, the curing temperature is
24
preferably for example in a range of the room temperature to 250°C, and the curing time is
preferably in a range of 0.5 minute to 3 hours. Alternatively, a method may be employed
in which the curable resin is cured by being irradiated with energy ray such as ultraviolet
light or electron beam. In such a case, the amount of the irradiation is preferably in a range
of20 mJ/cm2 to 5 J/cm2
.
[0071] Subsequently, the metal substrate is detached from the curable resin layer after the
cunng. The method for detaching the metal substrate is not limited to a mechanical
releasing (exfoliating or peeling off) method, and a publicly known method can be adopted.
Accordingly, a film-shaped resin mold, which can be obtained in such a manner and which
has the cured resin layer having the concavities and convexities and formed on the
supporting substrate, may be used as the mold for concave-convex pattern transfer of the
present embodiment.
[0072] Further, it is possible to coat the concave-convex structure (pattern) of the metal
substrate obtained in the above-described manner with a rubber-based resin material, to
cure the coated resin material, and to release the cured resin material from the metal
substrate, so as to manufacture a rubber mold having the concave-convex pattern of the
metal substrate transferred thereto. The obtained rubber mold may be used as the mold for
concave-convex pattern transfer of the present embodiment. Silicone rubber or a mixture
or copolymer of silicone rubber and another material is particularly preferably used as the
rubber-based resin material. The usable silicone rubber is exemplified, for example, by
polyorganosiloxane, cross-linking type polyorganosiloxane, a
polyorganosiloxane/polycarbonate copolymer, a polyorganosiloxane/polyphenylene
copolymer, a polyorganosiloxane/polystyrene copolymer, polytrimethyl-silylpropyne,
poly-4-methyl pentene, etc. The silicone rubber is more inexpensive than other resin
materials; has superior heat resistance, high heat conductivity, and elasticity; and the
silicone rubber is less likely to be deformed under a high temperature condition. Thus, the
silicone rubber is suitable for the transfer process for concave-convex pattern under the
high temperature condition. Further, since the silicone rubber-based material has high
permeability of gas and water vapor, a solvent and water vapor of a material to be
subjected to transfer can go through or permeate the silicone rubber material easily.
Therefore, the silicone rubber-based material is suitable for such a case of using the rubber
mold for the purpose of transferring the concave-convex pattern to a film of a solution of a
precursor of the inorganic material, as described later. Further, the surface free energy of
25
rubber-based material is preferably not more than 25 mN/m. With this, it is possible to
obtain a superior mold-releasing property during the transfer of the concave-convex pattern
of the rubber mold to the coating film on the base member, thereby making it possible to
prevent any transfer failure. The rubber mold may have, for example, a length in a range
of 50 mm to I 000 mm, a width in a range of 50 mm to 3000 mm, and a thickness in a
range of I mm to 50 mm. Further, a mold-release treatment may be performed on the
surface of the concave-convex pattern ofthe rubber mold as needed.
[0073]
In the method for manufacturing the gas barrier member of the first embodiment,
as depicted in Fig. 5(a), the first film 60 is firstly formed, as the first gas barrier layer, on a
concave-convex pattern of a mold 140 having the above-described concave-convex pattern
(step S1 ofFig. 4).
[0074] The first film 60 may be formed by a wet process. The "wet process" in the
present application includes, for example, a method of coating the mold with the precursor
of the inorganic material and curing the coating film; a method of coating the mold with a
dispersion liquid of fine particles and drying the coating film; a method of coating the
mold with a resin material and curing the coating film; and a liquid phase deposition (LPD)
method. The film formed by any of these wet process may contain an ultraviolet absorbent
material.
[0075] For example, when the first film 60 is formed by the method of coating the mold
with the precursor of the inorganic material and curing the coating film, alkoxide or the
like, such as silicon alkoxide or titanium alkoxide, may be used as the precursor of the
inorganic material (sol-gel method). Alternatively, polysilazane may be used as the
precursor of the inorganic material. The polysilazane is oxidized by being heated or being
irradiated with an energy ray such as excimer, is thereby ceramicized (subjected to silica
reforming or modification) and forms silica, SiN or SiON. Note that the "polysilazane" is
a polymer having a silicon-nitrogen bond, is an inorganic polymer comprising Si-N, Si-H,
N-H, or the like, and is a precursor of a ceramics such as Si02, ShN4, or SiOxNy, which is
an intermediate solid solution of such a ceramics. A compound, which is ceramized at
relatively low temperature and is modified into silica or the like, as that represented by the
following general formula (1) described in Japanese Patent Application Laid-open No.
H08-1 I2879, is more preferable.
[0076] General formula (1): -Si (Rl) (R2)-N (R3)-
26
In the general formula (1), R1, R2, and R3 each represent a hydrogen atom, an
alkyl group, an alkenyl group, a cycloalkyl group, an aryl group, an alkylsilyl group, an
alkylamino group, or an alkoxy group.
[0077] Among the compounds represented by the general formula (1),
perhydropolysilazane (referred to also as PHPS) in which all of R1, R2, and R3 are
hydrogen atoms and organopolysilazane in which a part of the hydrogen bonded to Si
thereof is substituted by, for example, an alkyl group are particularly preferable.
[0078] As other examples of the polysilazane ceramized at low temperature, it is also
possible to use: silicon alkoxide-added polysilazane obtained by reacting polysilazane with
silicon alkoxide (for example, Japanese Patent Laid-Open No. 5-238827); glycidol-added
polysilazane obtained by reaction with glycidol (for example, Japanese Patent Laid-open
No. 6-122852); alcohol-added polysilazane obtained by reaction with alcohol (for example,
Japanese Patent Laid-open No. 6-240208); metal carboxylate-added polysilazane obtained
by reaction with metal carboxylate (for example, Japanese Patent Laid-Open No. 6-
299118); acetylacetonato complex-added polysilazane obtained by reaction with an
acetylacetonato complex containing a metal (for example, Japanese Patent Laid-Open No.
6-306329); metallic fine particles-added polysilazane obtained by addition of metallic fine
particles (for example, Japanese Patent Laid-Open No. 7-196986), and the like.
[0079] As the solvent of the polysilazane solution, it is possible to use hydrocarbon
solvents such as aliphatic hydrocarbons, alicyclic hydrocarbons, and aromatic
hydrocarbons; halogenated hydrocarbon solvents; and ethers such as aliphatic ethers and
alicyclic ethers. Amine or a metal catalyst may be added in order to promote the
modification into a silicon oxide compound.
[0080] The following describes an example in which the first film 60 made from the
inorganic material is formed by the sol-gel method. At first, metal alkoxide as the
precursor is prepared. For example, when the first film 60 made from silica is formed,
those usable as the silica precursor include, for example, tetraalkoxide monomers
represented by tetraalkoxysilane such as tetramethoxysilane (TMOS), tetraethoxysilane
(TEOS), tetra-i-propoxysilane, tetra-n-propoxysilane, tetra-i-butoxysilane, tetra-nbutoxysilane,
tetra-sec-butoxysilane, and tetra-t-butoxysilane; trialkoxide monomers
represented by trialkoxysilane such as methyltrimethoxysilane, ethyltrimethoxysilane,
propyltrimethoxysilane, isopropyltrimethoxysilane, phenyltrimethoxysi1ane,
methyltriethoxysilane (MTES), ethyltriethoxysi1ane, propyltriethoxysilane,
27
isopropyltriethoxysilane, phenyltriethoxysilane, methyltripropoxysilane,
ethyltripropoxysilane, propyltripropoxysilane, isopropyltripropoxysilane,
phenyltripropoxysilane, methyltriisopropoxysilane, ethyltriisopropoxysilane,
propyltriisopropoxysilane, isopropyltriisopropoxysilane, phenyltriisopropoxysilane, and
tolyltriethoxysilane; and dialkoxide monomers represented by dialkoxysilane such as
dimethyldimethoxysilane, dimethyldiethoxysilane, dimethyldipropoxysilane,
dimethyldiisopropoxysilane, dimethyldi-n-butoxysilane, dimethyldi-i-butoxysilane,
dimethyldi-sec-butoxysilane, dimethyldi-t-butoxysilane, diethyldimethoxysilane,
diethyldiethoxysilane, diethyldipropoxysilane, diethyldiisopropoxysilane, diethyldi-nbutoxysilane,
diethyldi-i-butoxysilane, diethyldi-sec-butoxysilane, diethyldi-t-butoxysilane,
dipropyldimethoxysilane, dipropyldiethoxysilane, dipropyldipropoxysilane,
dipropyldiisopropoxysilane, dipropyldi-n-butoxysilane, dipropyldi-i-butoxysilane,
dipropyldi-sec-butoxysilane, dipropyldi-t-butoxysilane, diisopropyldimethoxysilane,
diisopropyldiethoxysilane, diisopropyldipropoxysilane, diisopropyldiisopropoxysilane,
diisopropy ldi -n-butoxysilane, di isopropy ldi-i -butoxysi lane, di isopropyldi -sec-butoxysilane,
diisopropyldi-t-butoxysilane, diphenyldimethoxysilane, diphenyldiethoxysilane,
diphenyldipropoxysilane, diphenyldiisopropoxysilane, diphenyldi-n-butoxysilane,
diphenyldi-i-butoxysilane, diphenyldi-sec-butoxysilane, and diphenyldi-t-butoxysilane.
Further, it is possible to use alkyltrialkoxysilane or dialkyldialkoxysilane which has alkyl
group having C4 to C 18 carbon atoms. It is also possible to use metal alkoxides including,
for example, monomers having vinyl group such as vinyltrimethoxysilane and
vinyltriethoxysilane; monomers having epoxy group such as 2-(3,4-
epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropylmethyldimethoxysilane, 3-
glycidoxypropyltrimethoxysilane, 3-glycidoxypropylmethyldiethoxysilane, and 3-
glycidoxypropyltriethoxysilane; monomers having styryl group such as pstyryltrimethoxysilane;
monomers having methacrylic group such as 3-
methacryloxypropylmethyldimethoxysilane, 3-methacryloxypropyltrimethoxysilane, 3-
methacryloxypropylmethyldiethoxysilane, and 3-methacryloxypropyltriethoxysilane;
monomers having acrylic group such as 3-acryloxypropyltrimethoxysilane; monomers
having amino group such as N-2-(aminoethyl)-3-aminopropylmethyldimethoxysilane, N-2-
(aminoethyl)-3-aminopropyltrimethoxysilane, 3-aminopropyltrimethoxysilane, 3-
aminopropyltriethoxysilane, 3-triethoxysilyl-N -( 1 ,3-dimethyl-butylidene )propylamine, and
N-phenyl-3-aminopropyltrimethoxysilane; monomer having ureide group such as 3-
28
ureidepropyltriethoxysilane; monomers having mercapto group such as 3-
mercaptopropylmethyldimethoxysilane and 3-mercaptopropyltrimethoxysilane; monomers
having sulfide group such as bis(triethoxysilylpropyl) tetrasulfide; monomers having
isocyanate group such as 3-isocyanatopropyltriethoxysilane; polymers obtained by
polymerizing the foregoing monomers in small amounts; and composite materials
characterized in that functional group and/or polymer is/are introduced into a part of the
material as described above. Further, a part of or all of the alkyl group and the phenyl
group of these compounds may be substituted with fluorine. Further, examples of the
silica precursor include metal acetylacetonate, metal carboxylate, oxychloride, chloride,
and mixtures thereof. The silica precursor, however, is not limited to the above examples.
In addition to Si, examples of the metal species include Ti, Sn, AI, Zn, Zr, In, and mixtures
thereof, but are not limited to these. It is also possible to use any appropriate mixture of
precursors of the oxides of the above metals. Further, it is possible to use, as the silica
precursor, a silane coupling agent having, in its molecule, a hydrolysis group having the
affinity and the reactivity with silica and an organic functional group having the waterrepellence.
For example, the silane coupling agent is exemplified by silane monomer such
as n-octyltriethoxysilane, methyltriethoxysilane, and methyltrimethoxysilane; vinylsilane
such as vinyltriethoxysilane, vinyltrimethoxysilane, vinyltris(2-methoxyethoxy)silane, and
vinylmethyldimethoxysilane; methacrylsilane such as 3-methacryloxypropyltriethoxysilane
and 3-methacryloxypropyltrimethoxysilane; epoxysilane such as 2-(3,4-
epoxycyclohexyl)ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, and 3-
glycidoxypropyltriethoxysilane; mercaptosilane such as 3-mercaptopropyltrimethoxysilane
and 3-mercaptopropyltriethoxysilane; sulfursilane such as 3-octanoylthio-1-
propyltriethoxysilane; aminosilane such as 3-aminopropyltriethoxysilane, 3-
aminopropyltrimethoxysilane, N-(2-aminoethyl)-3-aminopropyltrimethoxysilane, N-(2-
aminoethyl)-3-aminopropylmethyldimethoxysilane, and 3-(N-phenyl)aminopropyltrimethoxysilane;
and polymers obtained by polymerizing the monomers as
described above.
[0081] When a mixture ofTEOS and MTES is used as the precursor of the inorganic
material, the mixture ratio thereof can be, for example, 1:1 in a molar ratio. The precursor
produces amorphous silica by being subjected to hydrolysis and polycondensation reaction.
An acid such as hydrochloric acid or an alkali such as ammonia is added in order to adjust
the pH of the solution as a synthesis condition. The pH is preferably not more than 4 or
29
not less than 10. Water may be added to perform the hydrolysis. The amount of water to
be added can be not less than 1.5 times, with respect to the amount of metal alkoxide
species, in the molar ratio.
[0082] Examples of a solvent of the precursor solution used in the sol-gel method include
alcohols such as methanol, ethanol, isopropyl alcohol (IPA), and butanol; aliphatic
hydrocarbons such as hexane, heptane, octane, decane, and cyclohexane; aromatic
hydrocarbons such as benzene, toluene, xylene, and mesitylene; ethers such as diethyl
ether, tetrahydrofuran, and dioxane; ketones such as acetone, methyl ethyl ketone,
isophorone, and cyclohexanone; ether alcohols such as butoxyethyl ether, hexyloxyethyl
alcohol, methoxy-2-propanol, and benzyloxyethanol; glycols such as ethylene glycol and
propylene glycol; glycol ethers such as ethylene glycol dimethyl ether, diethylene glycol
dimethyl ether, and propylene glycol monomethyl ether acetate; esters such as ethyl acetate,
ethyl lactate, and y-butyrolactone; phenols such as phenol and chlorophenol; amides such
as N,N-dimethylformamide, N,N-dimethylacetamide, and N-methylpyrrolidone; halogencontaining
solvents such as chloroform, methylene chloride, tetrachloroethane,
monochlorobenzene, and dichlorobenzene; hetero-element containing compounds such as
carbon disulfide; water; and mixture solvents thereof. Especially, ethanol and isopropyl
alcohol are preferable. Further, a mixture of water and ethanol and a mixture of water and
isopropyl alcohol are also preferable.
[0083] As an additive of the precursor solution used in the sol-gel method, it is possible
to use polyethylene glycol, polyethylene oxide, hydroxypropylcellulose, and polyvinyl
alcohol for viscosity adjustment; alkanolamine such as triethanolamine, ~-diketone such as
acetylacetone, ~-ketoester, formamid, dimetylformamide, dioxane, and the like, as a
solution stabilizer. Further, as an additive of the precursor solution, it is possible to use a
material which can generate an acid or alkali by being irradiated with light such as energy
rays represented by ultraviolet rays such as excimer UV light. By adding such a material,
the precursor solution can be gelled (cured) by being irradiated with light, thereby making
it possible to form the inorganic material.
[0084] As depicted in Fig. 5(a), the concave-convex pattern ofthe mold 140 is coated
with the precursor solution of the inorganic material (the solution of the inorganic material
precursor) prepared as described above to form the first film (precursor film) 60. The mold
for the concave-convex pattern transfer described above can be used as the mold 140, and a
flexible film-shaped mold is preferably used as the mold 140. For example, as depicted in
30
Fig. 6(a), the first film 60 can be formed on the film-shaped mold 140 by providing a back
roll29a over which the film-shaped mold 140 passes and a die coater 20 disposed to face
the back roll 29a with the film-shaped mold 140 sandwiched therebetween, feeding or
sending the film-shaped mold 140 to the vicinity of the tip of the die coater 20, and
discharging the precursor solution from the die coater 20. From a viewpoint of massproduction,
the film-shaped mold 140 is preferably coated with the precursor solution
continuously by the die coater 20 provided at a predetermined position while the filmshaped
mold 140 is continuously transported. Any coating method, such as the bar coating
method, spray coating method, die coating method, or ink-jet method, can be used as the
coating method of the film-shaped mold 140. Among them, the die coating method is
preferably used because a mold having a relatively large width can be coated uniformly
with the precursor solution and the coating can be quickly completed prior to curing of the
coated precursor solution (prior to change into the inorganic material).
[0085] As depicted in Fig. 6(a), the film-shaped mold 140 with the first film 60 may be
directly transported between pressing rolls 22a, 22b for a joining step as described later.
Or, before the joining step, the precursor of the inorganic material forming the first film 60
may be changed into the inorganic material to cure or harden the first film 60. In particular,
when the first film 60 is made from a material that causes degassing (generates gas) in
curing, the first film 60 is preferably cured before the joining step for the following reasons.
Namely, before the joining step, a surface, of the first film 60, on the side opposite to the
surface contacting with the mold 140 is exposed to the atmosphere (or the surrounding
environment), and thus gas generated during curing of the first film 60 is released to the
surrounding, not causing any pattern defect by bubbles in the first film 60. During the
joining step, however, the first film 60 is sandwiched between the second film 70 and the
mold 140 (see Fig. 5(c)). Thus, gas (bubbles) generated from the first film 60 may remain
between the second film 70 and the mold 140, which may cause a defect by bubbles in a
concave-convex pattern to be formed in the first film 60. In order to cure the first film 60,
the first film 60 is preferably heated in the atmosphere at temperatures ranging from room
temperature to 300°C. When a material that generates an acid or alkali by being irradiated
with light such as ultraviolet rays is added to the precursor solution, it is possible to cure
the first film 60 by irradiating the first film 60 with energy rays represented by ultraviolet
rays including, for example, excimer UV light to change the precursor into the inorganic
material. When the first film 60 is cured before the joining step as described above, the
31
film-shaped mold 140 with the first film 60 may be directly transported between the
pressing rolls 22a, 22b for the joining step, or may be wound around a roll. When the filmshaped
mold 140 is wound around the roll, it is advantageous to feed or unwound the filmshaped
mold 140 directly from the roll in the joining step.
[0086] In order to improve the adhesion property between the first film 60 and the second
film 70 (or between the first film 60 and the adhesive layer 30 as described later), a surface
modified layer may be provided on the cured first film 60. Examples of materials of the
surface modified layer include silane monomer such as n-octyltriethoxysilane,
methyltriethoxysilane, and methyltrimethoxysilane; vinylsilane such as
vinyltriethoxysilane, vinyltrimethoxysilane, vinyltris(2-methoxyethoxy)silane, and
vinylmethyldimethoxysilane; methacrylsilane such as 3-methacryloxypropyltriethoxysilane
and 3-methacryloxypropyltrimethoxysilane; epoxysilane such as 2-(3,4-epoxycyclohexyl)
ethyltrimethoxysilane, 3-glycidoxypropyltrimethoxysilane, and 3-
glycidoxypropyltriethoxysilane; mercaptosilane such as 3-mercaptopropyltrimethoxysilane
and 3-mercaptopropyltriethoxysilane; sulfursilane such as 3-octanoylthio-1-
propyltriethoxysilane; aminosilane such as 3-aminopropyltriethoxysilane, 3-
aminopropyltrimethoxysi lane, N -(2-aminoethy 1)-3 -aminopropy ltrimethoxysilane, N -(2-
aminoethyl)-3-aminopropylmethyldimethoxysilane, and 3-(N-phenyl)aminopropyltrimethoxysilane;
and polymers obtained by polymerizing the monomers as
described above. A titanium coupling agent may be used instead of the above silane
coupling agents. Alternatively, a surface modified layer may be provided in such a manner
that the surface of the first film 60 (the surface on the side opposite to the surface
contacting with the mold 140) is subjected to treatment with an energy ray, such as plasma
treatment, corona treatment, excimer irradiation treatment, or UV /03 treatment.
[0087] The first film 60 may be formed by a dry process instead of the above-described
wet process. For example, the first film 60 can be formed by depositing the inorganic
material, such as the inorganic oxide, inorganic nitride, inorganic oxynitride, inorganic
sulfide, or inorganic carbide on the concave-convex pattern ofthe mold 140 using a wellknown
dry process, such as a physical vapor deposition method (PVD) including
evaporation, sputtering, and the like; or a chemical vapor deposition method (CVD).
[0088] For example, when a film of metal oxide is formed as the first film on the
concave-convex pattern of the film-shaped mold by sputtering, it is possible to use a
sputtering apparatus 1 (}conceptually depicted in Fig. 7. The sputtering apparatus 10
32
includes a vacuum chamber 11. The vacuum chamber 11 may be formed in any shape
which keeps the inside of the vacuum chamber 1I in a reduced pressure state. The vacuum
chamber 1I typically has a rectangular parallelepiped shape, cylindrical shape, or the like.
In the vacuum chamber II, there are provided a feeding roll I2 that feeds the film-shaped
mold I40, a winding roll I4 that winds or rolls up the film-shaped mold I40 thereon, and a
coating roll 16 disposed on a transporting route of the film-shaped mold I40 from the
feeding roll I2 to the winding roll 14. Further, the vacuum chamber I1 may include a
guide roll (not depicted) that transports the film-shaped mold I40. A sputtering target 18 is
disposed to face the film-shaped mold I40 passing over the coating roll I6. The sputtering
target I8 may be metal or metal oxide. It is only required that the size of the sputtering
target 18 in a width direction (the direction perpendicular to Fig. 7) be larger than the
width ofthe film-shaped mold 140.
[0089] When the first film is formed by using the sputtering apparatus 10, pressure in the
vacuum chamber II is reduced to high vacuum at first. Then, metal atoms (and oxygen
atoms) are sputtered from the sputtering target by DC plasma or high-frequency plasma
while noble gas, such as Ar, and oxygen gas are being introduced into the vacuum chamber
II. Meanwhile, the film-shaped mold I40 is fed from the feeding fool I2 and transported
to the coating roll 16. The metal atoms sputtered from the sputtering target 18 react with
oxygen on the surface ofthe film-mold 140 to cause the deposition of metal oxide, while
the film-shaped mold 140 is passing over the coating roll I6 in a state of being brought into
contact with a surface of the coating roll I6. Next, the film-shaped mold 140 on which
metal oxide is deposited is wound around the winding roll I4. The film-shaped mold 140
may pass through the guide roll or the like on the way, as appropriate.
[0090] When a metal oxide film is formed as the first film on the concave-convex pattern
of the film-shaped mold by an electron beam heating evaporation method, it is possible to
use, for example, an electron beam heating evaporation apparatus configured as follows.
Namely, in a vacuum chamber that is formed similarly to the sputtering apparatus 10 to
include the feeding roll that feeds the film-shaped mold, the winding roll that winds or rolls
up the film-shaped mold thereon, and the coating roll disposed on the transporting route of
the film-shaped mold I40 from the feeding roll 12 to the winding roll 14, there are
provided a crucible that contains metal or metal oxide and is disposed to face the filmshaped
mold passing over the coating roll and an electron gun that irradiates the interior of
the crucible with an electron beam to evaporate metal or metal oxide. In that configuration,
33
the metal or metal oxide in the crucible may be heated and evaporated by the electron
beam while the film-shaped mold is being transported, so that metal oxide will be
deposited on the film-shaped mold passing over the coating roll. In that situation, it is
allowable to or not to introduce oxygen gas into the chamber depending on the degree of
oxidation of the material contained in the crucible and a targeted degree of oxidation of the
first film.
[0091] When a metal oxide film is formed as the first film on the concave-convex pattern
of the film-shaped mold by atmospheric-pressure plasma CVD, it is possible to use
methods described, for example, in Japanese Patent Application Laid-open Nos. 2004-
052028 and 2004-198902. An organometallic compound may be used as a raw material
compound, and the raw material compound may be in either a gaseous, liquid, or solid
state at normal temperature under normal pressure. When the raw material compound is
used in its gaseous state, the raw material compound can be introduced as it is into a
discharge space; on the other hand, when the raw material compound is in a liquid or solid
state, the material is used after being gasified once by means of heating, bubbling,
decompression, ultrasonic radiation, etc. In view of such a situation, preferred
organometallic compounds include, for example, a metal alkoxide of which boiling point is
not more than 200°C.
[0092] Examples of such metal alkoxide include a silicon compound such as silane,
tetramethoxysilane, tetraethoxysilane (TEOS), tetra-n-propoxysilane, etc.; a titanium
compound such as titanium methoxide, titanium ethoxide, titanium isopropoxide, titanium
tetraisopropoxide, etc.; a zirconium compound such as zirconium-n-propoxide, etc.,; an
aluminum compound such as aluminum ethoxide, aluminum triisopropoxide, aluminum
isopropoxide, etc.; antymony ethoxide; arsenic triethoxide; zinc acetylacetonate;
diethylzinc; and the like.
[0093] Further, cracking gas is used together with the gaseous raw material containing
these organometallic compounds to compose a reactive gas, for the purpose of cracking the
organometallic compounds to thereby obtain an inorganic compound. The cracking gas is
exemplified, for example, by hydrogen gas, methane gas, acetylene gas, carbon monoxide
gas, carbon dioxide gas, nitrogen gas, ammonia gas, nitrous oxide gas, nitrogen oxide gas,
nitrogen dioxide gas, oxygen gas, water vapor, fluorine gas, hydrogen fluoride, trifluoro
alcohol, trifluorotoluene, hydrogen sulfide, sulfur dioxide, carbon bisulfide, and chlorine
gas. For example, metal oxide can be formed by using oxygen gas, metal nitride can be
34
formed by using ammonia gas, and metal oxynitride can be formed by using ammonia gas
and nitrous oxide gas.
[0094] In the plasma CVD method, a discharge gas easily turned to a plasma state is
mainly mixed with the reactive gas. As the discharge gas, it is possible to use a nitrogen
gas; a rare gas such as a gas of an element of the eighteenth group of the periodic table,
specifically, helium, neon, argon, etc.; and the like. In particular, the nitrogen gas is
preferably used in view of the production cost.
[0095] The film formation is performed by mixing the discharge gas with the reactive gas
to thereby obtain a mixed gas, and by supplying the mixed gas to a discharge plasma
generating apparatus (plasma generator). The ratio of the discharge gas relative to the
reactive gas is different depending on the property of a film as an object to be formed, and
the percentage of the discharge gas in the entire mixed gas is not less than 50%.
[0096] For example, silicon alkoxide (such as tetraethoxysilane (TEOS)), which is one of
the metal alkoxides having boiling point of not more than 200°C, is used as the raw
material compounds, oxygen is used as the cracking gas, and the rare gas or an inert gas
such as nitrogen is used as the discharge gas, and the plasma discharge is performed. Thus,
it is possible to form a film of silicon oxide as the first film.
[0097] In the CVD method as described above, it is possible to deposit any one of metal
carbide, metal nitride, metal oxide, metal sulfide, metal halide, or mixtures thereof (e.g.,
metal oxynitride, metal oxide halide, and metal nitride carbide) by selecting conditions
such as the metal compound as the raw material, cracking gas, decomposition temperature,
and power to be inputted or supplied. Thus, the film is preferably obtained by CVD
method.
[0098] In order to improve the adhesion property between the first film formed by the dry
process as described above and the second film (or the adhesive layer) which will be
described later, a surface modified layer may be provided on the first film. The surface
modified layer can be formed by using any of those listed as the materials and methods that
may be used for the case in which the surface modified layer is provided on the first film
formed by the wet process.
[0099]
Subsequently, as depicted in Fig. 5(b), the second film 70 is formed, as the second
gas barrier layer, on the base member 40 (step S2 of Fig. 4). A film-shaped base member
may be used as the base member 40. The second film 70 may be formed by any of the wet
35
process and the dry process which have been explained as the formation method of the first
film 60. As depicted in Fig. 6(a), when the first film 60 is formed by the wet process and
the joining step is performed by transporting the first film in an uncured state between the
pressing rolls 22a, 22b, the second film 70 formed by the wet process is cured before the
joining step, or the second film 70 is formed by the dry process. When the first film 60
formed by the wet process is cured before the joining step, or when the first film 60 is
formed by the dry process, the second film 70 is formed by the wet process and the second
film in an uncured state is subjected to the joining step.
[0100] When the second film 70 formed by the wet process is cured, or when the second
film 70 is formed by the dry process, a surface modified layer may be provided on the
second film 70 to improve the adhesion property between the first film 60 (or the adhesive
layer as described later) and the second film 70. The surface modified layer can be formed
by using any of those listed as the materials and methods that may be used for the case in
which the surface modified layer is provided on the first film 60. When the second film 70
formed by the wet process is cured, or when the second film 70 is formed by the dry
process, the film-shaped base member 40 with the second film 70 may be directly
transported between the pressing rolls 22a, 22b to perform the joining step, or it may be
wound around a roll. When the film-shaped base member 40 is wound around the roll, it is
advantageous to feed or unwound the film-shaped base member directly from the roll
during the joining step.
[0101] The first film formation step may be performed before the second film formation
step, the second film formation step may be performed before the first film formation step,
or the first film formation step and the second film formation step may be performed at the
same time.
[0102]
Subsequently, as depicted in Fig. 5(c), the mold 140 and the base member 40 are
overlapped with each other, so as to join or bond the first film 60 and the second film 70
(step S3 of Fig. 4). For example, as depicted in Fig. 6(a), sending the film-shaped mold
140 with the first film 60 and the film-shaped base member 40 with the second film 70
between the pressing rolls 22a, 22b allows the mold 140 and the base member 40 to
overlap with each other and allows the first film 60 and the second film 70 to adhere to (be
brought into tight contact with) each other. Then, the first film 60 or the second film 70 is
cured. For example, the first film 60 or the second film 70 can be cured by being heated or
36
irradiated with an energy ray, such as ultraviolet ray, by use of an UV lamp 25 or the like
as depicted in Fig. 6(a). Accordingly, the first film 60 and the second film 70 are fixed to
each other in the state of being joined between the film-shaped base member 40 and the
film-shaped mold 140.
[0103] Such a roll process using the pressing rolls 22a and 22b has the following
advantages over the pressing system. For example, it is possible to reduce joining pressure
and releasing force (peeling force) owing to the line contact between the first film 60 on
the film-shaped mold 140 and the second film 70 on the film-shaped base member 40,
thereby making it possible to easily manufacture a gas barrier member with larger area;
and it is possible to press the film-shaped mold 140 against the entire surface of the filmshaped
base member 40 uniformly, thereby bringing the first film 60 into tight contact with
the second film 70 uniformly and preventing any adhesion failure.
[0104] Those preferably used as the pressing rolls 22a and 22b include, for example, a
roll having a heat-resistant coating film provided on a roll surface and made from a resin
material, such as ethylene-propylene-diene rubber (EPDM), silicone rubber, nitrile rubber,
fluoro rubber, acrylic rubber, or chloroprene rubber.
[0105]
After the first film 60 and the second film 70 are joined to each other, as depicted
in Fig. 5(d), the mold 140 is released from the first film 60 (step S4 of Fig. 4). Any
publicly known releasing method can be adopted as the mold releasing method. In a case
of using the mold with concave-convex pattern in which each of convexities and
concavities has an elongated shape and a waveform structure in which inclination is gentle,
there is an advantage that releasing property (releasablity or peeling property) is
satisfactory. Further, since the first film 60 is firmly joined to the second film 70 by curing
the first film 60 or the second film 70 in the joining step, there is no possibility that any
portions of the first film 60 is released from the base member 40 in a state of adhering to
the mold 140. In the roll process, releasing force may be smaller than that in the pressing
system, and the mold 140 can be easily released from the first film 60 without allowing the
first film 60 to remain on the mold 140. Further, a releasing roll may be used to improve
the mold releasability. As depicted in Fig. 6(a), releasing rolls (peeing rolls) 23a, 23b are
disposed downstream of the pressing rolls 22a, 22b. The releasing roll23a rotates and
supports the film-shaped mold 140 with the first film 60 while urging the film-shaped mold
140 with the first film 60 against the film-shaped base member 40 with the second film 70,
37
and the releasing roll 23b rotates and supports the film-shaped base member 40 with the
second film 70 while urging the film-shaped base member 40 with the second film 70
against the film-shaped mold 140 with the first film 60. With this configuration, it is
possible to maintain a state in which the first film 60 adheres to the second film 70 as long
as a distance between the pressing rolls 22a, 22b and the releasing rolls 23a, 23b (for a
certain period of time). Then, a path of the film-shaped mold 140 is changed so that the
film-shaped mold 140 is pulled up above the releasing roll23a on the downstream side of
the releasing roll 23a and a path of the film-shaped base member 40 is changed so that the
film-shaped base member 40 is pulled down below the releasing roll 23b on the
downstream side ofthe releasing roll 23b, thereby releasing (peeling off) the film-shaped
mold 140 from the first film 60. The first film 60 from which the mold 140 is released is
formed with the concave-convex pattern 80 that has been transferred from (is
corresponding to) the concave-convex pattern formed on the surface of the mold 140.
[0106] In order to prevent such a situation that the mold 140 is released from the first film
60 in a state where the first film 60 partially adheres to the mold 140, the adhesive force
between the first film 60 and the mold 140 is preferably not more than 200 N/m, more
preferably not more than 100 N/m. The adhesive force between the first film 60 and the
mold 140 can be measured as follows. A supporting substrate is coated with the material
for the first film 60 to form a coating film, and the supporting substrate is overlapped with
the mold such that the coating film is brought into tight contact with (adheres to) the
concave-convex pattern surface of the mold. Then, the coating film is cured. Accordingly,
a sample having a structure formed by the supporting substrate/the first film/the mold is
obtained. This sample is cut into strips of 30 mm width, and the mold is released from the
first film by pulling an end of the mold upward at a constant speed in a normal direction of
the supporting substrate by use of a tensile tester (STROGRAPH E-H produced by Toyo
Seiki Seisaku-sho, Ltd.). The tensile strength of the mold represents the adhesive force
between the first film and the mold.
[0107] As described above, it is possible to manufacture the gas barrier member 100, as
depicted in Figs. 1(a) and 5(d), in which the second film 70 and the first film 60 are formed
on the base member 40 in that order.
[0108] A covering layer (coating layer) may be formed on the surface ofthe first film 60
of the gas barrier member 100. The thickness of the covering layer is preferably in a range
of 25% to 150% of the standard deviation of depth of concavities and convexities of the
38
concave-convex pattern 80 formed in the first film 60. Such a covering layer can cover
any foreign matter and/or defect which might be present on the concave-convex pattern.
Thus, when a light emitting element such as an organic EL element is formed by using the
gas barrier member, it is possible to effectively prevent any leak current in the light
emitting element. Further, a light emitting element, which is formed by using the gas
barrier member provided with the covering layer having a thickness within the above range,
has good light extraction efficiency.
[0109] The covering layer can be formed through the above-described wet process by
using any of the materials usable as the material for the first film. It is especially
preferable that the covering layer be formed by using a material that is same as the material
used as the material for the first film. Forming the covering layer and the first film by use
ofthe same material can prevent light reflection at an interface between the covering layer
and the first film.
[0110] Further, a hydrophobization treatment may be performed on the surface of the first
film (the surface of the covering layer when the covering layer is formed). Any known
method for the hydrophobization treatment may be used. For example, regarding the
surface of silica, the hydrophobization treatment can be performed with dimethyl
dichlorosilane, trimethyl alkoxysilan, etc., or with a silicone oil and a trimethylsilylating
agent such as hexamethyl-disilazane. Alternatively, it is also allowable to employ a
surface treatment method for a surface of metal oxide powder with supercritical carbon
dioxide. Allowing the surface of the first film to have hydrophobicity makes it possible to
easily remove moisture from the gas barrier member during a manufacturing process of a
light emitting element, such an organic EL element, in which the gas barrier member
manufactured through the manufacturing method of the first embodiment is used. This
makes it possible to prevent, in the light emitting element, any generation of defect, such as
a dark spot, and any deterioration of the device.
[0111] Further, a protective layer may be formed on the surface of the first film (the
surface of the covering layer when the covering layer is formed). Examples of resins that
may be used for forming the protective layer include solvent-based resins and water-based
resins which are exemplified, for example, by polyester-based resin, urethane-based resin,
acrylic-based resin, polyvinyl alcohol-based resin, ethylene-unsaturated carboxylate
copolymer resin, ethylene-vinyl alcohol-based resin, vinyl-modified resin, nitrocellulosebased
resin, silicone-based resin, isocyanate-based resin, epoxy-based resin, oxazoline
39
group-containing resin, modified styrenic-based resin, modified silicone-based resin, and
alkyl titanate. Only one kind of the resin as described above may be used singly, or two or
more kinds of the resins may be used in combination. In order to improve the barrier
property, wear property, and sliding property, a layer that is obtained by mixing one or
more kinds of inorganic particles selected among silica sol, alumina sol, particulate
inorganic filler, and layered inorganic filler with one or more of the above-listed resins or a
layer that is made from inorganic particle-containing resin formed by polymerizing the raw
material of any ofthe above-listed resins in presence of any ofthe above-listed inorganic
particles, is preferably used as the protective layer.
[0112] In addition to the covering layer and the protective layer, various functional layers
may be provided on the surface of the first film. Examples of the functional layers include
optical functional layers such as an antireflection layer, a polarization layer, a color filter,
and an ultraviolet-ray absorption layer; mechanical functional layers such as a hard coating
layer and a stress-relaxation layer; electric functional layers such as an antistatic layer and
a conductive layer; an anti fogging layer; an antifouling layer; and a layer to be printed.
[0113] Although the above embodiment describes the method for manufacturing the gas
barrier member by using the film-shaped mold, the gas barrier member can be
manufactured by using a hard mold, such as a metal mold or a quartz mold, in a manner
similar to the above-described manufacturing method. When the hard mold is used, a
flexible base member, such as a film-shaped base member, is preferably used as the base
member. In the joining step of the above embodiment, the pressing rolls are pressed
against the back surface of the film-shaped mold and the back surface of the film-shaped
base member. When the hard mold and the film-shaped base member are used, the
pressing roll may be pressed against a back surface (an opposite surface of the surface with
the second film) of the film-shaped base member in the joining step. This allows the hard
mold to be pressed against the entire surface of the film-shaped base member uniformly.
In the releasing step of the above embodiment, the film-shaped mold is released from the
first film, the film-shaped base member and the second film by urging the releasing rolls
from the sides ofthe back surfaces ofthe film-shaped mold and the film-shaped base
member toward each other and changing paths of the film-shaped mold and the filmshaped
base member at the downstream of the releasing rolls. When the hard mold and the
film-shaped base member are used, the film-shaped base member, the second film and the
first film are preferably released from the hard mold by urging the releasing roll from the
40
back surface of the film-shaped base member toward the hard mold and changing the route
(path) ofthe film-shaped base member at the downstream of the releasing roll. With this
configuration, small releasing force easily releases the mold 140 from the first film 60
without residue of any portions of the first film on the mold.
[0114] Although the above embodiment describes the method for manufacturing the gas
barrier member by using the film-shaped base member, the gas barrier member can be
manufactured by using a hard base member, such as a glass substrate, in a manner similar
to the above-described manufacturing method. When the hard base member is used, a
flexible mold, such as a film-shaped mold, is preferably used as the mold. In the joining
step of the above embodiment, the pressing rolls are pressed against the back surface of the
film-shaped mold and the back surface of the film-shaped base member. When the hard
base member and the film-shaped mold are used, the pressing roll may be pressed against a
back surface (an opposite surface ofthe surface with the concave-convex pattern) of the
film-shaped mold in the joining step. This allows the film-shaped mold to be pressed
against the entire surface of the hard base member uniformly. In the releasing step of the
above embodiment, the film-shaped mold is released from the first film, the film-shaped
base member, and the second film by urging the releasing rolls from the sides of the back
surfaces of the film-shaped mold and the film-shaped base member toward each other and
changing paths of the film-shaped mold and the film-shaped base member at the
downstream of the releasing rolls. When the hard base member and the film-shaped mold
are used, the film-shaped mold is preferably released from the hard base member, the
second film, and the first film by urging the releasing roll from the back surface of the
film-shaped mold toward the hard base member and changing the path of the film-shaped
mold at the downstream of the releasing roll. With this configuration, small releasing force
easily releases the mold 140 from the first film 60 without residue of any portions of the
first film on the mold.
[0115] The member having films formed on the base member is typically manufactured
by sequentially stacking or depositing the films on the base member. In that case, a film to
be stacked first needs to be a film that is not damaged by stacking of a subsequent film,
and each subsequent film needs to be stacked by a method not damaging the film to be
stacked first. Thus, film materials and staking methods (coating methods or depositing
methods) therefor are limited, which makes it impossible, in some cases, to form a film
with a desired function by using a desired material. Meanwhile, in the method for
41
manufacturing the gas barrier member according to the present embodiment, the first film
is formed on the concave-convex pattern of the mold and the second film is formed on the
base member, and then the first film and the second film are joined in an overlapped
manner, as described above. Thus, stacking of the first film does not damage the second
film, and staking of the second film does not damage the first film. Accordingly, the
method for manufacturing the gas barrier member according to the present embodiment
has such an advantage that composing materials and coating or depositing methods for the
first film and the second film are not restricted and the first film and the second film can be
formed by desired materials and desired methods.
[0116] In a general nanoimprint method, when a member with a concave-convex pattern
is manufactured by using a mold with a concave-convex pattern, a base member is coated
with a transfer material having relatively high fluidity through the wet process, and the
transfer material is cured while being pressed against the concave-convex pattern surface
of the mold. In this method, the transfer material is limited to those which can be applied
on the base member by coating and is not be degassed in curing, and thus a film with a
desired function can not be formed by using a desired material in some cases. Meanwhile,
in the method for manufacturing the gas barrier member of the present embodiment, the
first film formed on the concave-convex pattern of the mold is joined onto the base
member as described above and then the mold is released from the first film, thereby
forming the first film to which the concave-convex pattern of the mold has been transferred.
Namely, the member with the concave-convex pattern is manufactured by applying or
depositing the transfer material on the concave-convex pattern and allowing the transfer
material to adhere to the base member side. Thus, it is possible to use, as the transfer
material, materials that can be applied by a method rather than the coating, such as a dry
process, and materials that are degassed in curing.
[0117] As described above, the manufacturing method of the present embodiment has a
wide choice of composing materials and film-forming methods for the first film and the
second film, thus making it possible to manufacture a functional member with a good
function, such as a gas barrier member with a good gas barrier property. The gas barrier
member manufactured by the manufacturing method of the present embodiment is suitably
used for organic EL elements, liquid crystal displays, solar cells, and the like those of
which need a high gas barrier property. Further, the gas barrier member manufactured by
the manufacturing method of the present embodiment is suitably used for packaging
42
applications, such as packaging of goods and packaging for preventing any deterioration of
foods, industrial goods, medical products, and the like. When the gas barrier member
manufactured by the manufacturing method of the present embodiment is used for
packaging applications, there is an advantage that an irregular minute concave-convex
pattern, as depicted in Figs. 2(a) and 2(b), formed on the surface of the gas barrier member
can prevent haze and glare in appearance, as well as an advantage that a packaged product
can be protected with a high gas barrier property. When the member manufactured by the
manufacturing method of the present embodiment is a film-shaped member, the concaveconvex
pattern formed on the surface prevents blocking (sticking of the member) which
would be otherwise caused when the member is stored in an overlapped manner or in a
roll-shape. Thus, the member manufactured by the manufacturing method of the present
embodiment also has the advantage of easy storage.
[0118] The manufacturing method of the present embodiment can form the concaveconvex
pattern without photolithography that causes a large amount of waste liquid, and
thus the manufacturing method of the present embodiment is environmentally friendly.
Further, the manufacturing method of the present embodiment can continuously produce
the gas barrier member at high speed by using the roll process, and thus the manufacturing
method of the present embodiment has high production efficiency. When the first film or
the second film is cured before the joining step, the film-shaped mold with the cured first
film or the base member with the cured second film can be stored by being wound into a
roll. Thus, production adjustment is easily made, thereby making it possible to produce the
member with the concave-convex pattern efficiently.
[0119] [First modified embodiment of method for manufacturing gas barrier member]
An explanation will be made about a first modified embodiment of the method for
manufacturing the gas barrier member. The first modified embodiment of the method for
manufacturing the gas barrier member mainly includes: a step of forming the first film on
the concave-convex pattern of the mold; a step of forming the second film on the base
member; a step of forming the adhesive layer on the first film formed on the mold or the
second film formed on the base member; a step of joining the first film and the second film
via the adhesive layer; and a step of releasing the mold from the first film. In the first
embodiment, the first film or the second film is cured in the joining step to fix the first film
and the second film in a state that the first and second films are joined each other. In the
first modified embodiment, the first film and the second film are joined and fixed via the
43
adhesive layer.
[0120]
The first film is formed, as the first gas barrier layer, on the concave-convex
pattern of the mold by a method similar to the first embodiment. In the first modified
embodiment, the first film can be formed similarly to the first embodiment by the wet
process or the dry process. When the first film is formed by the wet process, the first film
is cured before an adhesive layer formation step which will be described later.
[0121]
The second film is formed, as the second gas barrier layer, on the base member by
a method similar to the first embodiment. In the first modified embodiment, the second
film can be formed similarly to the first embodiment by the wet process or the dry process.
When the second film is formed by the wet process, the second film is cured before the
adhesive layer formation step.
[0122]
Subsequently, the adhesive layer is formed by applying adhesive on the first film
formed on the mold or the second film formed on the base member. For example, as
depicted in Fig. 6(b ), the adhesive layer 30 is formed on the second film 70 by feeding or
sending the base member 40 with the second film 70 to the vicinity of the tip of a die
coater 21 and discharging adhesive from the die coater 21. From a viewpoint of massproduction,
adhesive is preferably applied on the second film 70 continuously by the die
coater 21 provided at a predetermined position while the base member 40 is continuously
transported. Any coating method, such as the bar coating method, spin coating method,
spray coating method, dip coating method, die coating method, or ink-jet method, can be
used as the adhesive applying method. Among them, the bar coating method, die coating
method, and spin coating methods are preferably used because a base member having a
relatively large area can be coated uniformly with adhesive and the coating can be quickly
completed prior to curing of adhesive.
[0123] When the adhesive is applied on the second film, the first film formation step may
be performed after the adhesive layer formation step. When the adhesive is applied on the
first film, the second film formation step may be performed after the adhesive layer
formation step.
[0124]
Subsequently, the base member and the mold are overlapped with each other in a
44
state where the first film and the second film are joined to each other via the adhesive layer.
For example, as depicted in Fig. 6(b), the first film 60 and the second film 70 can be
brought into tight contact with each other via the adhesive layer 30 in a state where the
base member 40 and the mold 140 are overlapped with each other by sending the filmshaped
mold 140 with the first film 60 and the base member 40 with the second film 70
and the adhesive layer 30 between the pressing rolls 22a, 22b. Further, the adhesive layer
30 is cured after the first film 60 and the second film 70 are brought into tight contact with
each other as described above. As depicted in Fig. 6(b ), the adhesive layer 30 can be cured
by being irradiated with an energy ray, such as ultraviolet ray, by use of the UV lamp 25 or
the like. Accordingly, the first film 60 and the second film 70 are joined and fixed to each
other via the adhesive layer 30 between the base member 40 and the film-shaped mold 140.
[0125]
The mold is released from the first film after the first film and the second film are
joined via the adhesive layer. The mold can be released by a method similar to the first
embodiment.
[0126] As described above, it is possible to manufacture the gas barrier member 1 OOa, as
depicted in Fig. 1 (b), having the concave-convex pattern 80, in which the second film 70
and the first film 60 are formed on the base member 40 in that order, and the adhesive
layer 30 is formed between the first film 60 and the second film 70.
[0127] [Second modified embodiment of method for manufacturing gas barrier member]
A film different from the first film may be formed on the first film formed on the
mold after the first film formation step of the first embodiment or the first modified
embodiment. The film different from the first film may be a single layer film or a
multilayer film. When the film different from the first film is formed, the first film and the
film that is different from the first film and formed on the first film form the first gas
barrier layer. The film different from the first film may be formed similarly to the first
film by the dry process or the wet process, such as coating. A stress relaxation layer may
be provided between respective layers.
[0128] A film different from the second film may be formed on the second film formed
on the base member after the second film formation step of the first embodiment or the
first modified embodiment. The film different from the second film may be a single layer
film or a multilayer film. When the film different from the second film is formed, the
second film and the film that is different from the second film and formed on the second
45
film form the second gas barrier layer. The film different from the second film may be
formed similarly to the second film by the dry process or the wet process, such as coating.
A stress relaxation layer may be provided between respective layers.
[0129] In the joining step of the second modified embodiment, the first film and the
second film are joined via the film different from the first film and/or the film different
from the second film. In the present invention, the wording "the first film and the second
film are joined" includes not only the case in which the first film and the second film are
joined directly or via the adhesive layer but also the case in which the first film and the
second film are joined via the film different from the first film and/or the film different
from the second film.
[0130] [Second gas barrier member]
As depicted in Fig. 8(a), a gas barrier member 300 with a concave-convex
structure (concave-convex pattern) 380, which is obtained by the second embodiment of
the method for manufacturing the gas barrier member with the concave-convex pattern
which will be described later, includes a first film 360 that is formed, as the first gas barrier
layer, on a base member 340 via an adhesive layer 330. As depicted in Fig. 8(b ), a gas
barrier member 300a, which is obtained by the fourth modified embodiment of the method
for manufacturing the gas barrier member with the concave-convex pattern which will be
described later, further includes a second film 370 that is formed, as the second gas barrier
layer, on the base member 340.
[0131]
As the base member 340, any of the substrates usable as the base member 40 of
the first gas barrier member 100 may be used as appropriate.
[0132]
The gas barrier member 300 includes the first film 360, as the first gas barrier
layer, which prevents permeation of oxygen and water vapor. As the material forming the
first film 360, it is preferable to use inorganic materials, such as metal oxide, metal nitride,
metal oxynitride, metal sulfide, and metal carbide, and it is more preferable to use
inorganic oxide, inorganic nitride, and inorganic oxynitride, such as silicon oxide,
aluminum oxide, silicon nitride, silicon oxynitride, aluminum oxynitride, magnesium oxide,
zinc oxide, indium oxide, tin oxide, titanic oxide, copper oxide, cerium oxide, and tantalum
oxide.
[0133] The water vapor transmission rate of the first film 360 is preferably not more than
46
1 o-2 g·m-2·dai1 to allow the gas barrier member 300 to have a sufficient gas barrier
property. Such a first film 360 is formed by the dry process such as a vapor evaporation
method, sputtering method, or CVD method, as described later.
[0134] The first film 360 preferably has a light transmission property. The first film 360
preferably has a transmittance of not less than 80% at a measurement wavelength of 550
nm, more preferably has a transmittance of not less than 90% at the measurement
wavelength of 550 nm.
[0135] The thickness of the first film 360 is preferably in a range of 5 nm to 2 )liD. When
the thickness is less than 5 nm, there are many cases of film defect, and any sufficient
moisture-preventing effect (gas barrier effect) cannot be obtained. When the thickness
exceeds 2 )liD, the time required for film formation is increased to reduce production
efficiency. In this context, the thickness of the first film 360 means an average value of
distances from the bottom surface of the first film 360 to the surface in which the concaveconvex
pattern 380 is formed.
[0136] The surface of the first film 360 is formed to have the minute concave-concave
pattern (concave-convex structure) 380. The minute concave-concave pattern 380 may be
any pattern similar to the concave-convex pattern 80 of the first gas barrier member 100.
[0137] Although Fig. 8(a) depicts a structure in which the first gas barrier layer is formed
by the first film 360 as a single layer, the first gas barrier layer may be formed by a
multilayer film including the first film 360 and at least one film that is different from the
first film 360 and disposed under the first film 360 (on a side, of the first film 360, facing
the base member 340, namely, a position between the first film 360 and the adhesive layer
330). Each of the at least one film that is different from the first film 360 and disposed
under the first film 360 may be a film made from any of the inorganic materials listed as
the materials that may be used for the first film 360, or a film formed by the wet process,
such as coating method. The film formed by the wet process includes silicon oxide, silicon
nitride, and silicon oxynitride formed by applying, as a precursor, polysilazane,
perhydropolysilazane (PHPS), organopolysilazane, silicon alkoxide-added polysilazane,
glycidol-added polysilazane, alcohol-added polysilazane, metal carboxylate-added
polysilazane, acety1acetonato complex-added polysilazane, and metallic fine particlesadded
polysilazane and then forming them into ceramic by oxidation; Si02, Ti02, ZnO,
ZnS, ZrO, Ah03, BaTi03, SrTi02, ITO and the like formed by applying, as a precursor,
metal alkoxide and then curing it; Si02, Ti02, ZnO, ZnS, ZrO, Ah03, BaTi03, SrTi02, and
47
the like formed by applying a dispersion liquid of fine particles and then drying it; and the
like. From the viewpoint of the gas barrier property, it is allowable to use, as the material
for the at least one film that is different from the first film 360 and disposed under the first
film 360, materials used for the sealing material of the organic EL element, such as
XNR5516Z produced by NAGASE & CO., L TO.; TB3124 produced by THREEBOND
HOLDINGS CO., LTD.; and CELVENUS HOOl produced by Daicel Corporation. Further,
it is allowable to use a material including an ultraviolet absorbent material in any of the
above-listed materials. The ultraviolet absorbent material has the function or effect to
prevent deterioration of the film by absorbing ultraviolet rays and converting the light
energy into something harmless such as heat. Any publicly known agent may be used as
the ultraviolet absorbent material. Those usable as the ultraviolet absorbent material
include, for example, benzotriazole-based absorbents, triazine-based absorbents, salicylic
acid derivative-based absorbents, benzophenone-based absorbents, etc. A stress relaxation
layer may be provided between respective layers. As the stress relaxation layer, it is
possible to use any of the materials listed as the materials for the stress relaxation layer of
the first gas barrier member.
[0138] When the gas barrier member, of which first gas barrier layer is formed as the
multilayer film, is used as an optical substrate of a light-emitting element, the first gas
barrier layer preferably has a light transmission property. For example, the first gas barrier
layer preferably has a transmittance of not less than 80% at a measurement wavelength of
550 nm, more preferably has a transmittance of not less than 90% at the measurement
wavelength of 550 nm.
[0139] When the first gas barrier layer is formed as the multilayer film, the thickness of
the first gas barrier layer is preferably in a range of 5 nm to 20 Jlm. When the thickness is
less than 5 nm, there are many cases of film defect, and any sufficient moisture-preventing
effect (gas barrier effect) cannot be obtained. When the thickness exceeds 20 Jlm, although
the moisture-preventing effect is theoretically high, the internal stress is high, which in tum
makes the first gas barrier layer to be brittle. This makes it impossible to obtain any
desired moisture-preventing effect. Further, when the base member 340 is made from a
flexible material, there is such a fear that any damage including cracking, etc., might occur
in the first gas barrier layer due to any external factor such as bending, pulling after the
film formation, etc. In this context, the thickness of the first gas barrier layer means an
average value of distances from the bottom surface of the first gas barrier layer to the
48
surface in which the concave-convex pattern 380 is formed.
[0140] When the first gas barrier layer is formed as the multilayer film, the water vapor
transmission rate of the first gas barrier layer is preferably not more than 10-2 g·m-2·dai1
to allow the gas barrier member 300 to have an enough gas barrier property. In that case,
the water vapor transmission rate of the first film 360 may exceed 1 o-2 g·m-2·dai1
•
[0141]
The gas barrier member 300 includes the adhesive layer 330 between the base
member 340 and the first film 360. When the first gas barrier layer is formed only of the
first film 360, when the first gas barrier layer is formed only of a film formed by the dry
process, or when a lowermost layer (a layer facing the base member 340) of the first gas
barrier layer is a film formed by the dry process, the first film 360 and the base member
340 are joined via the adhesive layer 330. The thickness of the adhesive layer 330 is
preferably in a range of 500 nm to 20 f!m. When the first gas barrier layer is formed by the
first film 360 and at least one film that is different from the first film 360 and disposed
under the first film 360 (on the side facing the base member 340), and the lowermost layer
(the layer facing the base member 340) of the first gas barrier layer is a film formed by the
wet process, the first film 360 and the base member 340 may be joined via the film that is
the lowermost layer of the first gas barrier layer and is formed by the wet process, thus
making it possible to eliminate the adhesive layer 330. Namely, the adhesive layer 330 is
not an indispensable element for the member manufactured by the manufacturing method
according to the second embodiment of the present invention.
[0142] As the material for the adhesive layer 330, it is possible to use any of those listed
as the materials that may be used for the adhesive layer 30 of the gas barrier member 1 OOa.
[0143]
As depicted in Fig. 8(b ), the gas barrier member 300a, which is obtained by the
fourth modified embodiment of the method for manufacturing the gas barrier member with
the concave-convex pattern which will be described later, includes the second film 370, as
the second gas barrier layer, between the base member 340 and the adhesive layer 330. As
the material for the second film 370, it is possible to use any of those listed as the inorganic
materials or the organic materials (resin materials) that may be used for the first film 360.
The second film 370 may be formed by the dry process or the wet process as described
later.
[0144] When the gas barrier member 300a is used as an optical substrate of a light
49
emitting element, the second film 370 preferably has a light transmission property. For
example, the second film 370 preferably has a transmittance of not less than 80% at a
measurement wavelength of 550 nm, more preferably has a transmittance of not less than
90% at the measurement wavelength of 550 nm.
[0145] The thickness of the second film 370 is preferably in a range of 5 nm to 20 ~-tm.
When the thickness is less than 5 nm, there are many cases of film defect, and any
sufficient moisture-preventing effect (gas barrier effect) cannot be obtained. When the
thickness exceeds 20 ~-tm, although the moisture-preventing effect is theoretically high, the
internal stress is high, which in turn makes the second film 370 to be brittle. This makes it
impossible to obtain any desired moisture-preventing effect. Further, when the base
member 340 is made from a flexible material, there is such a fear that any damage
including cracking, etc., might occur in the second film 370 due to any external factor such
as bending, pulling after the film formation, etc.
[0146] Although Fig. 8(b) depicts a structure in which the second gas barrier layer is
formed by the second film 370 as a single layer, the second gas barrier layer may be
formed by a multilayer film including the second film 370 and at least one film different
from the second film 370. The at least one film different from the second film 370 may be
made from any of those listed as the materials that may be used for the second film 370. A
stress relaxation layer may be provided between respective layers.
[0147] When the gas barrier member, of which second gas barrier layer is formed as the
multilayer film, is used as an optical substrate of a light-emitting element, the second gas
barrier layer preferably has a light transmission property. The second gas barrier layer
preferably has a transmittance of not less than 80% at a measurement wavelength of 550
nm, more preferably has a transmittance of not less than 90% at the measurement
wavelength of 550 nm.
[0148] When the second gas barrier layer is formed as the multilayer film, the thickness
of the second gas barrier layer is preferably in a range of 5 nm to 20 ~-tm. When the
thickness is less than 5 nm, there are many cases of film defect, and any sufficient
moisture-preventing effect (gas barrier effect) cannot be obtained. When the thickness
exceeds 20 ~-tm, although the moisture-preventing effect is theoretically high, the internal
stress is high, which in turn makes the second gas barrier layer to be brittle. This makes it
impossible to obtain any desired moisture-preventing effect. Further, when the base
member 340 is made from a flexible material, there is such a fear that any damage
50
including cracking, etc., might occur in the second gas barrier layer due to any external
factor such as bending, pulling after the film formation, etc.
[0149] When the second gas barrier layer is formed as the multilayer film, the water
vapor transmission rate of the second gas barrier layer is preferably not more than 10-2
g·m-2·da/ to allow the gas barrier member to have an enough gas barrier property. In that
case, the water vapor transmission rate of the second film may exceed 10-2 g·m-2·dai1
.
[0150] [Second embodiment of method for manufacturing gas barrier member]
An explanation will be made about the second embodiment of the method for
manufacturing the gas barrier member. As depicted in Fig. 9, the method for
manufacturing the gas barrier member mainly includes: a step Tl of forming the first film
on the concave-convex pattern of the mold by the dry process; a step T3 of joining the base
member to the first film formed on the mold; and a step T4 of releasing the mold from the
first film. Before the joining step T3, it is allowable to provide a step T2 of applying
adhesive on the first film formed on the mold or a surface of the base member to be joined
to the first film. In the following, the mold with the concave-convex pattern and the
manufacturing method thereof will be explained first, and then the steps T1 to T4 will be
sequentially explained with reference to Figs. 10(a) to 10(d).
[0151]
As the mold used in the method for manufacturing the gas barrier member
according to the second embodiment, it is possible to use a mold similar to that used in the
method for manufacturing the gas barrier member according to the first embodiment.
[0152]
As depicted in Fig. 1 O(a), in the method for manufacturing the gas barrier member
according to the second embodiment, the first film 360 is formed, as the first gas barrier
layer, on a surface of the mold 140 in which the concave-convex pattern is formed (step T1
of Fig. 9). The first film 360 can be formed by depositing the inorganic material, such as
metal oxide, metal nitride, metal oxynitride, metal sulfide, or metal carbide on the
concave-convex pattern surface of the mold 140 by a well-known dry process, such as a
physical vapor deposition method (PVD) including evaporation, sputtering, and the like; or
a chemical vapor deposition method (CVD). The first film 360 formed by such a dry
process has a low water vapor transmission rate and a high gas barrier property.
[0153] The first film 360 can be formed, for example, by the sputtering, electron beam
heating evaporation method, atmospheric-pressure plasma CVD, or the like described in
51
the first embodiment of the method for manufacturing the gas barrier member.
[0154] A surface modified layer may be provided on the first film 360 to improve the
adhesion property between the first film 360 and the adhesive layer 330 which will be
described later. The surface modified layer can be formed by any of those listed as the
materials and the methods that may be used for the surface modified layer provided on the
first film 60 in the first embodiment of the method for manufacturing the gas barrier
member.
[0155]
Subsequently, as depicted in Fig. 1 O(b ), adhesive is applied on the base member
340 to form the adhesive layer 330 (step T2 of Fig. 9). For example, as depicted in Fig.
11 (a), the adhesive layer 330 is formed on the base member 340 by feeding or sending the
base member 340 to the vicinity of the tip of a die coater 320, and discharging adhesive
from the die coater 320. From a viewpoint of mass-production, the adhesive is preferably
applied on the base member 340 continuously by the die coater 320 provided at a
predetermined position while the base member 340 is continuously transported. As the
adhesive applying method, it is possible to use any of those listed as the methods for
applying adhesive in the first modified embodiment of the method for manufacturing the
gas bas barrier member.
[0156] When adhesive is applied on the base member 340, the adhesive applying step
may be performed before the first film formation step. Before applying adhesive on the
base member 340, a surface modified layer may be provided on the base member 340 to
improve the adhesion property between the base member 340 and the adhesive layer 330.
The surface modified layer can be formed, similarly to the case in which the surface
modified layer is formed on the first film 360, in such a manner that the surface of the base
member 340 is coated with a coupling agent or the surface of the base member 340 is
subjected to treatment with an energy ray, such as plasma treatment, corona treatment,
excimer irradiation treatment, or UV/03 treatment, etc. The adhesive layer 330 may be
formed on the first film 360 instead of formed on the base member 340.
[0157]
Subsequently, as depicted in Fig. 1 O(c), the first film 360 and the base member
340 are joined via the adhesive layer 330 by pressing the mold 140 with the first film 360
against the base member 340 with the adhesive layer 330 in a state where they are
overlapped with each other (step T3 of Fig. 9). For example, as depicted in Fig. ll(a), the
52
C, Cc''''' ••C••~•-•c••c•-c'••c••c••~----CC•·•••••••••• c, .. ''"'''·'•'•" •c"'· ___ _
first film 360 can be brought into tight contact with the base member 340 in a state where
they are overlapped with each other by sending the film-shaped mold 140 with the first
film 360 between the pressing roll 22 and the base member 340 with the adhesive layer
330 that is being transported immediately below the pressing roll 22. Namely, when the
first film 360 formed on the film-shaped mold 140 is pressed against the base member 340
by use of the pressing roll22, the surface of the base member 340 and the adhesive layer
330 are covered (overlapped) with the first film 360 on the film-shaped mold 140 while the
film-shaped mold 140 and the base member 340 are being synchronously transported. In
this situation, by pressing the pressing roll 22 against the back surface (surface on the side
opposite to the surface in which the concave-convex pattern is formed) of the film-shaped
mold 140, the first film 360 on the film-shaped mold 140 moves with the adhesive layer
330 on the base member 340 while being brought into tight contact with the adhesive layer
330. In order to send the film-shaped mold 140 to the pressing roll 22, such a
configuration is conveniently used wherein the film-shaped mold 140 is fed directly from
the winding roll14 (see Fig. 7) that is used to wind or roll up the film-shaped mold 140
thereon in the first film formation step. Then, the adhesive layer 330 is cured after the first
film 360 and the adhesive layer 330 are brought into tight contact with each other as
described above. As depicted in Fig. 11 (a), the adhesive layer 330 can be cured by being
irradiated with an energy ray, such as ultraviolet ray, by use of the UV lamp 25 or the like.
Accordingly, the first film 360 is joined onto the base member 340 via the adhesive layer
330, and is fixed thereto.
[0158] Such a roll process using the pressing roll 22 has the following advantages. For
example, it is possible to reduce joining pressure and releasing force (peeling force) owing
to the line contact between the first film 360 on the film-shaped mold 140 and the adhesive
layer 330 on the base member 340, thereby making it possible to easily manufacture a gas
barrier member with a larger area; and it is possible to press the film-shaped mold 140
against the entire surface of the base member 340 uniformly, thereby bringing the first film
360 into tight contact with the base member 340 uniformly via the adhesive layer 330 and
preventing any tight adhesion failure.
[0159] As the pressing roll 22, it is possible to use a roll similar to the pressing rolls 22a
and 22b that are used in the first embodiment of the method for manufacturing the gas
barrier member. Further, a supporting roll may be provided to face the pressing roll 22 and
to sandwich the substrate 340 between the supporting roll and the pressing roll 22, or a
53
supporting stand configured to support the substrate 340 may be provided, for the purpose
of resisting the pressure applied by the pressing roll 22.
[0160]
As depicted in Fig. 1 0( d), the mold 140 is released from the first film 360 after the
first film 360 is joined on the base member 340 (step T4 of Fig. 9). Any publicly known
releasing method can be adopted as the mold releasing method. In a case of using the mold
with the concave-convex pattern in which each of concavities and convexities has an
elongated shape and a waveform structure in which inclination is gentle, there is an
advantage that mold releasability is good. Since the first film 360 is firmly joined to the
base member 340 via the cured the adhesive layer 330, there is no possibility that any
portions ofthe first film 360 is released from the base member 340 in a state of partially
adhering to the mold 140. In the roll process, releasing force may be smaller than that in
the pressing system, and the mold 140 is easily released from the first film 360 without
allowing the first film 360 to remain on the mold 140. Further, a releasing roll may be
used to improve the mold releasability. As depicted in Fig. 11 (a), a releasing roll (peeing
roll) 23 may be disposed downstream of the pressing roll 22. The releasing roll 23 rotates
and supports the film-shaped mold 140 and the first film 360 while urging them against the
base member 340 and the adhesive layer 330, thus maintaining a state in which the first
film 360 adheres to the adhesive layer 330 as long as a distance between the pressing roll
22 and the releasing roll 23 (for a certain period of time). Then, a path of the film-shaped
mold 140 is changed so that the film-shaped mold 140 is pulled up above the releasing roll
23 on the downstream side of the releasing roll 23, thereby releasing (peeling off) the filmshaped
mold 140 from the first film 360. The concave-convex pattern 380, which is
transferred from the concave-convex pattern formed on the surface of the mold 140, is
formed on the first film 360 from which the mold 140 is released.
[0161] As described above, it is possible to manufacture the gas barrier member 300, as
depicted in Fig. 8(a), in which the first film 360 is formed on the base member 340 and the
adhesive layer 330 is formed between the base member 340 and the first film 360.
[0162] Similar to the first embodiment of the method for manufacturing the gas barrier
member, a covering layer may be formed on the surface of the first film 360 of the gas
barrier member 300. A hydrophobization treatment may be performed on the surface of
the first film 360 (the surface of the covering layer when the covering layer is formed). A
protective layer or various functional layers may be formed on the surface of the first film
54
360 of the gas barrier member 300 (the surface of the covering layer when the covering
layer is formed). Instead of the film-shaped mold, it is allowable to use a hard mold, such
as a metal mold or a quartz mold.
[0163] In the method for manufacturing the gas barrier member according to the second
embodiment, the first film formed on the concave-convex pattern surface ofthe mold is
joined to the base member and the mold is released from the first film, which enables to
obtain the first film that is formed by the dry process and has the concave-convex pattern
transferred from the concave-convex pattern of the mold. In a case of forming the
concave-convex pattern in the film formed by the dry process, photolithography is
typically used. The manufacturing method of the second embodiment, however, can form
the concave-convex pattern without photolithography that causes a large amount of waste
liquid, and thus the manufacturing method of the second embodiment is environmentally
friendly. Further, the manufacturing method of the second embodiment can continuously
produce the member with the concave-convex pattern at high speed by using the roll
process, and thus the manufacturing method of the second embodiment has high
production efficiency. In a case of manufacturing the member with the concave-convex
pattern by using the mold with the concave-convex pattern, any of the following methods
is typically used: a method in which the base member is coated with a transfer material
having relatively high fluidity through the wet process and the concave-convex pattern
surface of the mold is pressed against the coating film; a method in which the concaveconvex
pattern of the mold is coated with a transfer material having relatively high fluidity,
the transfer material is allowed to permeate into the concave-convex pattern, and then the
transfer material is transferred to another member. In each of the above methods, the
transfer process restricts functions of the film with the concave-convex pattern formed by
each of the above methods, which makes it impossible, in some cases, to obtain a film with
a desired function. Meanwhile, the manufacturing method of the second embodiment can
manufacture a member with a desired function by depositing the inorganic material on the
convex-concave pattern through the dry process and transferring it to another member.
[0164] The gas barrier member manufactured by the manufacturing method of the second
embodiment includes, as the first gas barrier layer, the first film formed by the dry process.
Thus, the gas barrier member manufactured by the manufacturing method of the second
embodiment has a good gas barrier property. Thus, similar to the gas barrier member
manufactured by the manufacturing method of the first embodiment, the gas barrier
55
member manufactured by the manufacturing method of the second embodiment is suitably
used for organic EL elements, liquid crystal displays, solar cells, packaging applications,
and the like, and has the advantage of easy storage.
[0165] [Third modified embodiment of method for manufacturing gas barrier member]
At least one film different from the first film may be formed on the first film
formed on the mold after the first film formation step of the manufacturing method
according to the second embodiment is performed. The at least one film different from the
first film may be formed by the dry process similar to the first film or the wet process such
as coating. In the third modified embodiment, the first film and the at least one film that is
different from the first film and disposed on the first film form the first gas barrier layer.
Each film formed by the wet process may contain an ultraviolet absorbent material.
[0166] As a precursor of the inorganic material, alkoxide or the like, such as silicon or
titanium, may be used (sol-gel method). Or, polysilazane may be used as a precursor of
the inorganic material.
[0167] In the joining step (T3) of the third modified embodiment, the first film and the
base member are joined via the at least one film different from the first film. In the present
invention, the wording "joining the base member to the first film formed on the mold"
includes not only the case in which the first film and the base member are joined directly
or via the adhesive layer but also the case in which the first film and the base member are
joined via the at least one film different from the first film.
[0168] [Fourth modified embodiment of method for manufacturing gas barrier member]
A method for manufacturing the gas barrier member according to the fourth
modified embodiment includes, in addition to the respective steps of the manufacturing
method according to the second embodiment, a step of forming the second film, as the
second gas barrier layer, on the base member. The second film formation step is
performed before the adhesive applying step. In a case of forming the adhesive layer on
the first film formed on the mold during the adhesive applying step, it is only required that
the second film formation step be performed before the joining step, that is, the second
film formation step may be performed after the adhesive applying step. The second film
can be formed by the dry process or the wet process.
[0169] In a case offorming the second film, the adhesive applying step, the joining step,
and the releasing step, those of which will be subsequently performed, can be performed
similarly to the manufacturing method of the second embodiment. For example, as
56
depicted in Fig. ll(b), adhesive is applied on the second film 370 formed on the base
member 340 by the die coater 320 to form the adhesive layer 330 (adhesive applying step).
Then, the first film 360 and the second film 370 are brought into tight contact with each
other via the adhesive layer 330 by sending the film-shaped mold 140 with the first film
360 between the pressing roll 22 and the base member 340 that is formed with the second
film 370 and the adhesive layer 330 and is being transported immediately below the
pressing roll 22. Then, the first film 360 is joined and fixed onto the second film 370 by
curing the adhesive layer 330 through irradiation with ultraviolet ray or the like Uoining
step). Then, the mold 140 is pulled up above the releasing roll23, thereby releasing
(peeling off) the mold 140 from the first film 360 (releasing step). Accordingly, it is
possible to produce the gas barrier member 300a with the concave-convex pattern 380 in
which the second film 370 and the first film 360 are formed on the base member 340 in
that order and the adhesive layer 330 is formed between the first film 360 and the second
film 370, as depicted in Fig. 8(b).
[0170] A surface modified layer may be provided on the second film 370 to improve the
adhesion property between the second film 370 and the adhesive layer 330. The surface
modified layer can be formed by any of those listed as the materials and the methods that
may be used for the case in which the surface modified layer is provided on the first film
370.
[0171] At least one film different from the second film may be formed on the second film.
The at least one film that is different from the second film and disposed on the second film
may be formed by the dry process or the wet process. In that case, the second film and the
at least one film that is different from the second film and disposed on the second film
form the second gas barrier layer.
[0172] [Light emitting element]
Next, an explanation will be made about an embodiment of a light emitting
element manufactured by using the gas barrier member with the concave-convex pattern
that is obtained by any of the manufacturing methods according to the embodiments and
the modified embodiments. As depicted in Figs. 12(a), 12(b), 13(a), and 13(b), each ofthe
light emitting elements 200, 200a, 400, and 400a includes a first electrode layer 92, an
organic layer 94, and a second electrode layer 98 in that order on one of the gas barrier
members 100, 1 OOa, 300, and 300a. The gas barrier member 100 is formed by the base
member 40, the second film 70, and the first film 60; the gas barrier member 1 OOa is
57
formed by the base member 40, the second film 70, the adhesive layer 30, and the first film
60; the gas barrier member 300 is formed by the base member 340, the adhesive layer 330,
and the first film 360; and the gas barrier member 300a is formed by the base member 340,
the second film 370, the adhesive layer 330, and the first film 360. Each of the light
emitting elements 200, 200a, 400, and 400a may further include a sealing member 101 and
a sealing adhesive layer 103.
[0173]
The first electrode 92 may be a transparent electrode so that the light from the
organic layer 94 formed on the first electrode 92 passes toward the base member 40. The
first electrode 92 is preferably stacked such that the surface of the first electrode 92
maintains or shows the concave-convex pattern formed in the surface of the first film 60.
[0174] Those usable as the material for the first electrode 92 include, for example, indium
oxide, zinc oxide, tin oxide, indium-tin oxide (ITO) that is a composite material thereof,
gold, platinum, silver, and copper. Among these materials, ITO is preferable from the
viewpoint oftransparency and electrical conductivity. The thickness of the first electrode
92 is preferably within a range of 20 to 500 nm.
[0175]
The organic layer 94 is formed on the first electrode 92. The organic layer 94 is
not particularly limited, provided that the organic layer 94 is usable as an organic layer of
the organic EL element. As the organic layer 94, any publicly known organic layer can be
used as appropriate.
[0176] As depicted in Figs. 12(a), 12(b), 13(a), and 13(b), the surface ofthe organic layer
94 (an interface between the organic layer 94 and the second electrode 98) may be formed
to maintain the concave-convex pattern formed in the surface of each of the first films 60,
360. Or, the surface of the organic layer 94 may be flat without maintaining the concaveconvex
pattern formed in the surface of each of the first films 60, 360. When the surface
of the organic layer 94 is formed to maintain the concave-convex pattern formed in the
surface of each of the first films 60, 360, plasmon absorption due to the second electrode
98 is reduced to improve light extraction efficiency. Those usable as the material of the
hole transporting layer include, for example, aromatic diamine compounds such as
phthalocyanine derivatives, naphthalocyanine derivatives, porphyrin derivatives, N,N'bis(
3-methylphenyl)-(l, I' -biphenyl)-4,4' -diamine (TPD), and 4,4' -bis[N-(naphthyl)-Nphenyl-
amino]biphenyl(a-NPD); oxazole; oxadiazole; triazole; imidazole; imidazolone;
58
stilbene derivatives; pyrazoline derivatives; tetrahydroimidazole; polyarylalkane;
butadiene; and 4,4' ,4' '-tris(N-(3-methylphenyl)N-phenylamino )triphenylamine (mMTDATA).
The examples ofmaterials ofthe hole transporting layer, however, are not
limited to the above-described materials. The light emitting layer is provided in order that
a hole injected from the first electrode 92 and an electron injected from the second
electrode 98 are recombined to occur light emission. Those usable as the material of the
light emitting layer include, for example, metallo-organic complex such as anthracene,
naphthalene, pyrene, tetracene, coronene, perylene, phthaloperylene, naphthaloperylene,
diphenylbutadiene, tetraphenylbutadiene, coumarin, oxadiazole, bisbenzoxazoline,
bisstyryl, cyclopentadiene, and aluminum-quinolinol complex (Alq3); tri-(p-terphenyl-4-
yl)amine; l-aryl-2,5-di(2-thienyl) pyrrole derivatives; pyran; quinacridone; rubren;
distyrylbenzene derivatives; distyryl arylene derivatives; distyryl amine derivatives; and
various fluorescent pigments or dyes. Further, it is preferable that light-emitting materials
selected from the above compounds be mixed as appropriate and then used. Furthermore,
it is possible to preferably use a material system generating emission of light from a spin
multiplet, such as a phosphorescence emitting material generating emission of
phosphorescence and a compound including, in a part of the molecules, a constituent
portion formed by the above materials. The phosphorescence emitting material preferably
includes heavy metal such as iridium. A host material having high carrier mobility may be
doped with each of the light-emitting materials as a guest material to generate the light
emission using dipole-dipole interaction (Forster mechanism) or electron exchange
interaction (Dexter mechanism). Those usable as the material of the electron transporting
layer include, for example, heterocyclic tetracarboxylic anhydrides such as nitrosubstituted
fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide
derivatives, and naphthaleneperylene; and metallo-organic complex such as carbodiimide,
fluorenylidene methane derivatives, anthraquino dimethane and anthrone derivatives,
oxadiazole derivatives, and aluminum-quinolinol complex (Alq3). Further, in the
oxadiazole derivatives mentioned above, it is also possible to use, as an electron
transporting material, thiadiazole derivatives in which oxygen atoms of oxadiazole rings
are substituted by sulfur atoms and quinoxaline derivatives having quinoxaline rings
known as electron attractive group. Furthermore, it is also possible to use a polymeric
material in which the above materials are introduced into a macromolecular chain or the
above materials are made to be a main chain of the macromolecule. Note that the hole
59
transporting layer or the electron transporting layer may also function as the light-emitting
layer.
[0177] From the viewpoint of facilitating the electron injection from the second electrode
98, a layer made from a metal fluoride or metal oxide such as lithium fluoride (LiF) or
Lh03, a highly active alkaline earth metal such as Ca, Ba, or Cs, an organic insulating
material, or the like may be provided as an electron injection layer between the organic
layer 94 and the second electrode 98. Further, from the viewpoint of facilitating the hole
injection from the first electrode 92, it is allowable to provide, as a hole injection layer
between the organic layer 94 and the first electrode 92, a layer made from triazol
derivatives, oxadiazole derivative, imidazole derivative, polyarylalkane derivatives,
pyrazoline and pyrazolone derivatives, phenylenediamine derivative, arylamine derivatives,
amino-substituted calcone derivatives, oxazole derivatives, styrylanthracene derivatives,
fluorenone derivatives, hydrazone derivatives, stilbene derivatives, silazane derivatives,
aniline-based copolymers, or electroconductive high-molecular oligomar, particularly
thiophene oligomer.
[0178] Furthermore, when the organic layer 94 is a stacked body formed by the hole
transporting layer, the light emitting layer, and the electron transporting layer, the
thicknesses of the hole transporting layer, the light emitting layer, and the electron
transporting layer are preferably within a range of 1 nm to 200 nm, a range of 5 nm to 100
nm, and a range of 5 nm to 200 nm, respectively.
[0179]
The second electrode 98 is formed on the organic layer 94. As the material of the
second electrode 98, a substance having a small work function can be used as appropriate,
although the material of the second electrode 98 is not particularly limited to this. For
example, the second electrode 98 may be a metal electrode using aluminum, MgAg, Mgln,
AlLi, or the like. The thickness of the second electrode 98 is preferably in a range of 50 to
500 nm. The second electrode 98 may be stacked such that the surface of the second
electrode 98 maintains or shows the concave-convex pattern formed in the surface of the
first film 60. A polarizing plate may be put on the second electrode 98 to address specular
reflection ofthe second electrode 98 made from metal.
[0180]
The sealing member 101 is disposed to face each of the base members 40, 340 so
as to define a space (sealed space) 105 intervening between the sealing member 101 and
60
each of the base members 40, 340. The first electrode 92, the organic layer 94 and the
second electrode 98 are disposed in the sealed space I 05. The sealing member I 0 I can be
fixed to each of the base members 40, 340 by using the sealing adhesive layer I 03. The
sealing adhesive layer I 03 may be positioned between each of the bases members 40, 340
and the sealing member I 0 I in a Z direction (a normal direction of each of the base
members 40, 340) indicated in Figs. I2(a), I2(b ), I3(a), and I3(b ), and may be positioned
to surround the organic layer 94 in an XY direction (an in-plane direction of each of the
base members 40, 340). Owing to the presence of the sealing member I OI and the sealing
adhesive layer I 03, it is possible to prevent moisture and/or oxygen from entering the
sealed space I 05. With this, any degradation of the organic layer 94, etc., is reduced,
which in turn improves the service life of each of the light emitting element 200, 200a, 400,
and 400a. Further, in order to effectively extract the light emitted from the organic layer
94, the sealing adhesive layer I 03 is preferably formed to be separated from the organic
layer 94 by a predetermined spacing distance (clearance), without contacting the organic
layer 94. The predetermined spacing distance is preferably, for example, not less than I
f.!m.
[0181] The material of the sealing member I 01 may be any material having a high gas
barrier property. Those usable as the material of the sealing member IOI include, for
example, any publicly known gas barrier films used for packaging materials and the like,
such as a plastic film in which silicon oxide or aluminum oxide is deposited; a laminate
(stacked object) formed by a ceramic layer and an impact-attenuating polymer layer; metal
foil laminated with a polymer film; a sealing can made from glass; a sealing can made
from metal; and an engraved glass.
[0182] As the material of the sealing adhesive layer I 03, it is possible to use, without any
restriction, any adhesive widely used for glass, a plastic substrate, or the like. Further, it is
possible to use any of those listed above as the materials that may be used for the adhesive
layer 30.
[0183] The sealed space I 05 may be fi!Ied with an inactive or inert gas or the like. N2
can be used as the inactive gas, and instead ofN2, a noble gas such as He or Ar is
preferably used. Further, a noble gas obtained by mixing He with Ar is also preferable.
The ratio of the inactive gas in gases is preferably in a range of 90% by volume to I 00%
by volume. Alternatively, the sealed space I 05 may be filled with infilling such as a solid
or liquid resin, glass, an inactive oil such as a fluorine-based inactive oil, or a gel material.
61
The infilling is preferably transparent or cloudy. Further, a water-absorbing substance may
be disposed in the sealed space 105. The water-absorbing substance is exemplified, for
example, by barium oxide. Specifically, for example, high-purity barium oxide powder
produced by SIGMA-ALDRICH CO., LLC. can be disposed in the sealed space 105 by
being put or stuck on the sealing member 101 by using a tluororesin-based semitransparent
film with adhesive (MICROTEX S-NTF8031 Q produced by NITTO DENKO
CORPORATION) or the like. Alternatively, any commercially available water-absorbing
substances produced, for example, by W .L. Gore & Associates and Futaba Corporation are
preferably used.
[0184] Each of the light emitting elements 200, 200a, 400, and 400a may include an
optical functional layer on a surface of the base member 40 or the base member 340 on the
side opposite to the surface on which the first film 60 or the first film 360, etc. is/are
formed (the surface serving as a light-extracting surface of the light emitting element).
The optical functional layer is not particularly limited, provided that the optical functional
layer is usable for light extraction of the light emitting element. Any optical member
having a structure capable of extracting light to the outside of the element while controlling
refraction of light, concentration of light, diffusion (scattering) of light, diffraction of light,
reflection of light, and the I ike, can be used as the optical functional layer. As the optical
functional layer, various lens members, a diffusion sheet or plate formed by a transparent
body into which diffusion material is blended, a diffusion sheet or plate having a concaveconvex
structure (concave-convex pattern) on the surface thereof, a diffraction grating, a
member having an antireflection function, or the like may be used. The various lens
members include a convex lens such as the hemispherical lens, a concave lens, a Fresnel
lens, a prism lens, a cylindrical lens, a lenticular lens, a micro lens including a concaveconvex
layer that can be formed by a method similar to the method for manufacturing the
gas barrier member with the concave-convex structure layer as described above, and the
like. Of the above examples, each of the lens members is preferably used because light can
be extracted efficiently. Further, a plurality of lens members may be used as the optical
functional layer. In that case, a so-called micro lens (array) may be formed by arranging or
arraying fine or minute lens members. A commercially available product may be used for
the optical functional layer. Such an optical functional layer prevents light passing through
each of the base members 40, 340 from being totally reflected at an interface between each
of the base members 40, 340 (including the optical functional layer) and air, thereby
62
improving light extraction efficiency.
[0185] Each of the light emitting elements 200, 200a, 400, and 400a of the present
embodiment uses one of the gas barrier members 100, 1 OOa, 300, and 300a having a good
gas barrier property. This prevents deterioration due to moisture and/or oxygen, thus
allowing the light emitting element to have a long service life. Since each of the first films
60, 360 includes the concave-convex pattern working as a diffraction grating, each of the
light emitting elements 200, 200a, 400, and 400a has a good light emitting property.
[0186] Although the present invention has been explained as above with the
embodiments and modified embodiments, the member with the concave-convex structure
manufactured by the manufacturing method of the present invention is not limited to those
described in the above-described embodiments and modified embodiments, and may be
appropriately modified or changed within a range of the technical ideas described in the
following claims. For example, the member with the concave-convex structure
manufactured by the manufacturing method of the present invention is not limited to gas
barrier members used in optical elements. Namely, the manufacturing method of the
present invention can manufacture various functional members, in which a first functional ·
layer (first film) and a second functional layer (second film) having predetermined
functions are formed on a base member, and various functional members in which a layer
(first film) having a predetermined function is formed on a base member by the dry process.
Examples of the functional layers include a light reflection layer, a light scattering layer, an
insulating layer, an electrode pattern layer, a conductive layer, an antifogging layer, a heatinsulating
layer, an antifouling layer, an optical waveguide layer, a dielectric layer, a nonreflection
layer, a low-reflection layer, a polarization functional layer, a light diffraction
layer, a hydrophilic layer, and a water-repellent layer.
INDUSTRIAL APPLICABILITY
[0187] In the method for manufacturing the member with the concave-convex pattern
according to the first aspect of the present invention, there is very little restriction on the
materials and film-forming methods for the first film and the second film. Thus, the
method according to the first aspect can manufacture a functional member having a good
function. In the method for manufacturing the member with the concave-convex pattern
according to the second aspect of the present invention, it is possible to easily manufacture
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a member with a film that is formed by the dry process and has a surface formed with the
concave-convex pattern. In the manufacturing method according to each of the first and
second aspects of the present invention, the member with the concave-convex pattern is
formed by transfer of the concave-convex pattern of the mold, without photolithography
that causes a large amount of waste liquid, thus resulting in environmental friendliness and
high production efficiency. In particular, the gas barrier member can be manufactured by
forming films having a high gas barrier property, as the first film and the second film,
through the method for manufacturing the member with the concave-convex pattern
according to the first aspect, or by forming a film having a high gas barrier property
through the dry process in the method for manufacturing the member with the concaveconvex
pattern according to the second aspect. An organic EL element using such a gas
barrier member has a sufficient light emitting efficiency and a long service life due to the
suppression of the deterioration caused by moisture and/or gas including oxygen. The gas
barrier member obtained by the manufacturing method of the present invention can be
suitably used for, in addition to the organic EL element, the production of optical
substrates of various devices, such as liquid crystal displays and solar cells; the production
of optical elements, such as micro lens arrays, nanoprism arrays, and optical waveguides;
the production of optical components, such as lenses; the production of LED; the
production of solar cells; the production of antireflection films; the production of
semiconductor chips; the production of patterned media; the production of data storage; the
production of electronic paper; the production of LSI; packaging of goods; packaging
members for preventing any deterioration of foods, industrial goods, medical products, and
the like; the biology field, such as immunoassay chips and cell culture sheets; and the like.
Further, the method for manufacturing the member with the concave-convex pattern
according to the present invention can be used for the manufacture of members with
various functions, besides the gas barrier member.
Reference Sign List:
[0188] 30: adhesive layer, 40: base member, 60: first film, 70: second film, 80: concaveconvex
pattern, 92: first electrode, 94: organic layer, 98: second electrode, I 00, 1 OOa, 300,
300a: gas barrier member, 101: sealing member, 103: sealing adhesive layer, 140: mold,
200, 200a, 400, 400a: light emitting element, 330: adhesive layer, 340: base member, 360:
first film, 370: second film, 380: concave-convex pattern

We claim:
1. A method for manufacturing a member with a concave-convex pattern,
compnsmg:
a step of forming a first film on a concave-convex pattern formed on a surface of a
mold;
a step of forming a second film on a base member;
a step of joining the first film and the second film by overlapping the mold with
the base member; and
a step of releasing the mold from the first film joined to the second film.
2. The method for manufacturing the member with the concave-convex
pattern according to claim 1, further comprising a step of applying adhesive on the first
film formed on the mold or the second film formed on the base member before the joining
step.
3. The method for manufacturing the member with the concave-convex
pattern according to claim 1 or 2, further comprising a step of forming, on the first film
formed on the mold, a film different from the first film and/or a step of forming, on the
second film formed on the base member, a film different from the second film, before the
joining step.
4. A method for manufacturing a member with a concave-convex pattern,
comprising:
a step of forming a first film, through a dry process, on a concave-convex pattern
formed on a surface of a mold;
a step of joining a base member to the first film formed on the mold; and
a step of releasing the mold from the first film.
5. The method for manufacturing the member with the concave-convex
pattern according to claim 4, further comprising a step of applying adhesive on a surface of
the base member, which is to be joined to the first film formed on the mold, or on the first
film formed on the mold before the joining step.
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6. The method for manufacturing the member with the concave-convex
pattern according to claim 4 or 5, further comprising a step of forming a film different
from the first film, through the dry process and/or a wet process, on the first film formed
on the concave-convex pattern of the mold.
7. The method for manufacturing the member with the concave-convex
pattern according to any one of claims 4 to 6, wherein the first film is formed by depositing
silicon oxide, silicon oxynitride, or silicon nitride through the dry process in the step of
forming the first film.
8. The method for manufacturing the member with the concave-convex
pattern according to any one of claims 4 to 7, further comprising a step of forming a
second film on the base member before the joining step.
9. The method for manufacturing the member with the concave-convex
pattern according to any one of claims 1 to 3 and 8, wherein the first film and/or the second
film has/have a water vapor transmission rate of not more than 1 o-2 g·m-2·daf1
•
10. The method for manufacturing the member with the concave-convex
pattern according to claim 3, wherein a first gas barrier layer formed by the first film and
the film which is formed on the first film and different from the first film and/or a second
gas barrier layer formed by the second film and the film which is formed on the second
film and different from the second film has/have a water vapor transmission rate of not
more than 10-2 g·m-2·daf1
•
11. The method for manufacturing the member with the concave-convex
pattern according to any one of claims 1 to 10, wherein:
(i) each of a plurality of convexities and each of a plurality of concavities of the
concave-convex pattern of the mold has an elongated shape which extends while winding
in a plane view; and
(ii) the plurality of convexities have extending directions, bending directions and
lengths which are non-uniform among the plurality of convexities, and the plurality of
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concavities have extending directions, bending directions and lengths which are nonuniform
among the plurality of concavities.
12. The method for manufacturing the member with the concave-convex
pattern according to any one of claims 1 to 11, wherein the concave-convex pattern of the
mold is an irregular concave-convex pattern in which an average pitch of concavities and
convexities is in a range of 100 to 1500 nm and an average value of depth distribution of
the concavities and convexities is in a range of 20 to 200 nm.
13. The method for manufacturing the member with the concave-convex
pattern according to any one of claims 1 to 12, wherein a Fourier-transformed image of a
concavity and convexity analysis image of the mold shows a circular or annular pattern
substantially centered at an origin at which an absolute value of wavenumber is 0 !lm-1, and
the circular or annular pattern is present within a region where the absolute value of
wavenumber is in a range of not more than 1 0 !lm -1.
14. A member with a concave-convex pattern manufactured by the method
for manufacturing the member with the concave-convex pattern according to any one of
claims 1 to 13.
15. The member with the concave-convex pattern according to claim 14,
wherein the member with the concave-convex pattern includes a gas barrier layer, and the
first film is included in the gas barrier layer.
16. The member with the concave-convex pattern according to claim 15,
wherein the gas barrier layer has a water vapor transmission rate of not more than 10-2 g·m-
2·day-1.
17. An organic light emitting diode formed by successively stacking, on a
member with a concave-convex pattern manufactured by the method for manufacturing the
member with the concave-convex pattern according to any one of claims 1 to 13, a first
electrode, an organic layer, and a metal electrode.