DESCRIPTION
TRANSPARENT ELECTRODE, AND ORGANIC ELECTRONIC DEVICE
Technical Field
[000 I] The present invention relates to a transparent electrode utilized in an organic
electronic device of which typical examples include organic solar cells and organic
electroluminescence elements, and to an organic electronic device in which the transparent
electrode is utilized.
Background At1
[0002] Transparent electrodes are utilized in organic electronic devices. Such a transparent
electrode is arranged on a light-receiving surface side of a photoelectric conversion element of
which typical examples include organic solar cells. Such a transparent electrode is arranged
on a light -emitting snrface side of a light -emitting element of which typical examples include
organic EL ( electroluminescence) elements.
[0003] Indium tin oxide (ITO) has been frequently used as a transparent electrode material.
ITO contains indium oxide (In203) and a small percent of tin oxide (Sn02).
[0004] A method of producing a transparent electrode comprising ITO is disclosed in, for
example, Document 1. Specifically, an ITO application liquid formed by dispersing fine
ITO particles in a solvent is prepared. The ITO application liquid is applied onto a substrate.
The ITO application liquid on the substrate is heated at from 400 to 800°C to form an ITO
film (transparent electrode).
[0005] As described above, the transparent electrode comprising the ITO film is formed by
baking at the heating temperature described above. Therefore, it is necessary to prepare the
substrate having heat resistance that enables the substrate to endure the baking temperature.
The heat resistance of organic functional layers (electricity-generating layers or light-emitting
layers) included in organic electronic devices is low. Accordingly, it is impossible to form
the transparent electrode comprising the ITO film on such an organic functional layer.
[0006] Conductive polymer layers have been developed as transparent electrodes having low
baking temperature. Examples of the conductive polymer layers include PEDOT/PSS layers.
Such a PEDOT/PSS layer is disclosed in, for example, Document 2. Such a PEDOT/PSS
layer is produced by the following method. A dispersion liquid formed by dispersing poly
(3,4-ethylenedioxythiophene) (PEDOT) and polystyrene sulfonate (PSS) in water or the like
is prepared. The dispersion liquid is applied to a substrate, and the substrate is dried. The
PEDOT/PSS layer is formed by the above steps.
I
[0007] Document 3 proposes a transparent conductive film containing metalnanowires, as a
transparent electrode substituted for such ITO films and such conductive polymer layers.
The transparent conductive film disclosed in Document 3 contains a plurality of metal
nanowires, and an ionizing radiation curable resin. The average diameter of the metal
nanowires is from 40 to 1 00 nm, and the metalnanowires are contained in the transparent
conductive film. The metal nanowires are, for example, silver. In the transparent
conductive film, the metalnanowires intersect each other to form a network structure. As a
result, a conductive path is formed, and the conductivity of the transparent conductive film
can be obtained. Because the metal nanowires form the network structure, transparency can
be obtained. The transparent conductive film of Document 3 is formed by applying a
coating containing the metal nanowires onto a substrate or an organic functional layer, and
curing the coating by irradiation with light, or drying the coating in a manner similar to that of
Document 2.
[0008] In addition, transparent electrodes, or members corresponding to transparent
electrodes are also disclosed in Documents 4 to 8.
[0009] For a solar cell which is one of organic electronic devices, Document 9 discloses that
a stainless steel sheet is used as a substrate for a dye-sensitized solar cell. Document 10
discloses a solar cell in which a chromium-containing ferritic steel sheet is used as a substrate,
and in which CIGS (compound containing copper (Cu), indium (In), gallium (Ga), and
selenium (Se) as main raw materials) which is one of compound semiconductors is used.
Document 11 discloses a silicon-based solar cell in which a stainless steel sheet is used as a
substrate. Document 12 discloses an organic thin-film solar cell in which a cell structure is
formed on a glass substrate using an organic thin film.
[0010]
Document 1: Japanese Patent Application Laid-Open (JP-A) No. 2009-123396
Document 2: JP-ANo. 2013-185137
Document 3: JP-A No. 2012-216535
Document 4: JP-ANo. 2012-219333
Document 5: International Publication No. WO 2010/106899
Document 6: Japanese National-Phase Publication (JP-A) No. 2006-527454
Document 7: JP-A No. 2013-152579
Document 8: JP-A No. 2011-86482
Document 9: JP-ANo. 2012-201951
Document 10: JP-A No. 2012-97343
Document 11: JP-ANo. 2011-204723
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Document 12: Organic Electronics, 13 (2012) 2130-2137
SUMMARY OF INVENTION
Technical Problem
[00 11] The conductive polymer layers need not be baked at high temperature, and are easy
to form. Therefore, such a conductive polymer layer can be formed not only on a substrate
but also on an organic functional layer. However, the conductivity and light
transmissiveness of the conductive polymer layers are lower than those of ITO films.
In the transparent electrode in which the metal nanowires are utilized, the cost of the
metal nanowires is high. The gap portions (i.e., resin pmiions) other than the metal
nanowires in the network structure ofthe metal nanowires have no conductivity, and the
conductivity of the transparent electrode is low.
[0012] Therefore, for sufficiently exhibiting the function of the organic functional layer of
an organic electronic device, fhrther improvement in the conductivity and light
transmissiveness of a transparent electrode that can be formed on the organic functional layer
is currently demanded.
[0013] Thus, an object of the invention is to provide a transparent electrode that can also be
formed on an organic functional layer, and has high conductivity and high light
transmissiveness, as well as an organic electronic device including the transparent electrode.
Solution to Problem
[0014]
<1> A transparent electrode, comprising:
a conductive polymer layer; and
a plurality of carbon fibers having a diameter larger than a thickness of the
conductive polymer layer,
wherein the carbon fibers are partially embedded in the conductive polymer layer.
[0015]
<2> The transparent electrode according to claim 1, wherein the diameter of the carbon
fibers is from 2 to 90 times the thickness of the conductive polymer layer.
[0016]
<3> The transparent electrode according to claim 1 or claim 2, wherein the diameter of
the carbon fibers is from 2 to 15 f.UU, and the thickness of the conductive polymer layer is
fiom 5 to 650 mn.
[0017]
3
<4> The transparent electrode according to any one of claim I to claim 3, wherein lengths
of the carbon fibers are from 50 to 7000 pm.
[0018]
<5> The transparent electrode according to any one of claim I to claim 4, wherein an area
rate of the carbon fibers, in a case of being viewed from a direction perpendicular to a plane
of the transparent electrode, is from 40 to 90% with respect to the transparent electrode.
[0019]
<6> An organic electronic device, comprising:
a substrate;
a substrate electrode that is arranged on the substrate;
an organic functional layer that is arranged on the substrate electrode; and
the transparent electrode according to any one of claim 1 to claim 5, the transparent
electrode being arranged on the organic functional layer.
[0020]
<7> The organic electronic device according to claim 6, wherein the substrate is a coated
metal substrate or a plastic substrate.
[0021]
<8> The organic electronic device according to claim 6 or claim 7, wherein the organic
functional layer is an organic functional layer comprising an electricity-generating layer as a
photoelectric conversion layer.
[0022]
<9> The organic electronic device according to any one of claim 6 to claim 8, further
comprising a sealing layer that seals the substrate electrode, the organic functional layer, and
the transparent electrode.
Advantageous Effects of Invention
[0023] According to the invention, a transparent electrode that can also be formed on an
organic functional layer, and has high conductivity and high light transmissiveness, as well as
an organic electronic device including the transparent electrode can be provided.
BRIEF DESCRIPTION OF DRAWINGS
[0024] Fig. I is a schematic cross-sectional view of an organic electronic device accm'ding
to an embodiment.
Fig. 2 is a schematic cross-sectional view of a transparent electrode according to the
embodiment.
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Fig. 3 is a schematic plan view of the transparent electrode according to the
embodiment.
Fig. 4 is a schematic view illustrating the configuration of a solar cell module
according to the embodiment.
Fig. 5 is a view giving an explanation of a solar cell including two single cells (cell
structures) produced experimentally in Example B.
Fig. 6 is a schematic view for explaining an I-V curve of the solar cell produced
experimentally in Example B.
DESCRIPTION OF EMBODIMENTS
[0025] An embodiment which is an example of the invention will be described in detail
below with reference to the drawings. Components that are the same as or equivalent to
each other in the drawings may be denoted by the same reference characters, and the
descriptions thereof may be omitted.
[0026]
As illustrated in Fig. 1, an organic electronic device 1 according to the embodiment
includes a substrate 1 0, a substrate electrode II that is arranged on the substrate I 0, an
organic functional layer 12 that is arranged on the substrate electrode II, and a transparent
electrode 13 that is arranged on the organic functional layer 12. The organic electronic
device I also includes a sealing layer 14 that seals the substrate electrode II, the organic
functional layer 12, and the transparent electrode 13. The sealing layer 14 is a layer that is
disposed, if necessmy.
[0027] The transparent electrode 13 that is disposed as an upper electrode of the organic
electronic device 1 includes a conductive polymer layer 131, and a plurality of carbon fibers
132 having a diameter larger than the thickness of the conductive polymer layer 131, and the
carbon fibers 132 are partially embedded in the conductive polymer layer 131, as illustrated in
Fig. 2 to Fig. 3. "Carbon fibers 132 are partially embedded in conductive polymer layer
131" mem1s that a part of each fiber of the plurality of cm·bon fibers is embedded in the
conductive polymer layer 131.
[0028] The above-described configuration allows the organic electronic device I according
to the embodiment to become a device that sufficiently exhibits the function of the organic
functional layer 12. The reason for this is supposed as follows.
[0029] The transparent electrode 13 includes the plurality of carbon fibers 132 having high
conductivity. The carbon fibers 132 are in the state of being exposed from the conductive
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polymer layer 131 because the carbon fibers 132 have a diameter larger than the thickness of
the conductive polymer layer 131. The carbon fibers 132 are disposed to be patiially
embedded in the conductive polymer layer 131. Therefore, the carbon fibers 132 and a layer
with which the conductive polymer layer 131 comes in contact (the organic functional layer
12 in the embodiment) come in contact with each other, or the distances between the carbon
fibers 132 and the lower layer with which the conductive polymer layer comes in contact are
short. Thus, the state of facilitating direct conduction between the carbon fibers 132 and the
lower layer is achieved. The carbon fibers 132 are allowed to have a diameter larger than the
thickness of the conductive polymer, thereby facilitating a state in which the plurality of
carbon fibers 132 come in contact with each other. In addition, the gap poliions other than
the carbon fibers 132 are in the state of being imparted with conductivity by the conductive
polymer layer 131. As a result of the above, the conductivity of the transparent electrode 13
is improved.
[0030] The light transmissiveness of the transparent electrode 13 is improved because the
conductive polymer layer 131 having low light transmissiveness is disposed to have a larger
thickness than the diameter of the carbon fibers 132. The conductivity ofthe transparent
electrode 13 is improved by the carbon fibers 132 having high conductivity even in a case in
which the thickness of the conductive polymer layer 131 is reduced.
[0031] The transparent electrode 13 including the carbon fibers 132 and the conductive
polymer layer 131 can be formed at low temperature by, for example, application, drying, and
the like of an application liquid containing the carbon fibers 132 and a conductive polymer.
In other words, the transparent electrode 13 can also be formed on the organic functional layer
12.
[0032] Therefore, the transparent electrode 13 can also be formed on the organic functional
layer 12, and is presumed to have enhanced conductivity and light transmissiveness. The
organic electronic device 1 including the transparent electrode 13 is a device that sufficiently
exhibits the function ofthe organic functional layer 12.
[0033] Each component of the organic electronic device 1 will be described in detail below.
[0034] [Substrate 10]
The material of the substrate 10 is not particularly restricted. The substrate 10 may
contain a resin, or may contain an inorganic material of which typical examples include glass.
The substrate 10 may have light transmissiveness, or does not necessarily have light
transmissiveness.
[0035] Specifically, the substrate 10 may be an inorganic substrate including an inorganic
material such as, for example, glass, ceramic, or a metal, or may be a plastic substrate
6
including a resin such as an acrylic resin, a polycarbonate resin, a polyolefin resin, a polyester
resin, an epoxy resin, a urethane resin, a polyvinyl alcohol resin, a polyvinyl chloride resin, a
polyethylene resin, or a polyimide resin. For example, a surface of the substrate 10 may be
coated with an insulating layer, and the substrate electrode II may be formed on the
insulating layer in order to electrically insulate the substrate 10 from the substrate electrode 11
in a case in which the substrate 10 is a conductor such as a metal substrate. Examples of the
metal sheet include a coated metal sheet .
[0036] [Substrate Electrode 11]
The substrate electrode 11 is arranged on the substrate 10. The substrate electrode
11 has a well-known configuration. The substrate electrode 11 is, for example, a metallic
thin film. The metallic thin film is, for example, a thin film including a metal such as
aluminum, silver, or gold, or an alloy of aluminum, silver, gold, or the like. The substrate
electrode llmay be a thin film including metal nanowires, tin-doped indium tin oxide (ITO),
fluorine-doped tin oxide (FTO), aluminum-doped zinc oxide (ZAO), graphene, a conductive
polymer, or the like.
[0037] In a case in which the substrate electrode 11 is a thin film including a conductive
polymer, the substrate electrode 11 can be produced by a method that enables the film to be
formed at low temperature (for example, a spin coating method) rather than by a costly
method such as vapor deposition.
[0038] The thickness of the substrate electrode 11 is not particularly restricted, and is
preferably fi·om 0.5 to 3 J.lm, and more preferably fi·om 1 to 2 J.lm, in consideration of
performance and a cost.
[0039] [Organic Functional Layer 12]
The organic functional layer 12 is arranged on the substrate electrode 11. The
organic functional layer 12 is arranged between the substrate electrode 11 and the transparent
electrode 13. Examples of the organic functional layer 12 include an organic functional
layer including a photoelectric conversion layer (an electricity-generating layer, a
light-emitting layer, a light-receiving layer, or the like) in a case in which the organic
electronic device 1 is a photoelectric conversion element. The organic functional layer 12
may include a plurality of layers. In a case in which the organic functional layer 12 includes
the plurality of1ayers, the organic functional layer 12 means a layer in which at least one
layer includes an organic layer.
Specifically, the organic functional layer 12 includes, for example, a photoelectric
conversion layer 121, an electron transport layer 122 disposed on a side, closer to the
substrate electrode 11, of the photoelectric conversion layer 121, and a hole transpmt layer
7
123 disposed on a side, closer to the transparent electrode 13, of the photoelectric conversion
layer 121. For example, the photoelectric conversion layer 121 is an electricity-generating
layer in a case in which the organic electronic device I is a solar cell, the photoelectric
conversion layer 121 is a light-emitting layer in a case in which the organic electronic device
I is a light-emitting element, and the photoelectric conversion layer 121 is a light-receiving
layer in a case in which the organic electronic device I is an imaging element.
[0040] The organic functional layer 12 may have a configuration including only a light
conversion layer 12A, or may have a configuration including the light conversion layer 12A
and either the electron transpmi layer 122 or the hole transport layer 123. In addition, the
organic functional layer 12 may have a configuration including a layer other than the above,
for example, a hole injection layer, an electron injection layer, an insulating layer, an
antireflection layer, or the like.
[0041] [Transparent Electrode 13]
The transparent electrode 13 is arranged as an upper electrode on the organic
functional layer 12. The transparent electrode 13 includes the conductive polymer layer 131
and the plurality of carbon fibers 132.
[0042] (Conductive Polymer Layer 131)
The conductive polymer layer 131 contains a conductive polymer. The conductive
polymer is a polymer through which electricity can flow. Preferred examples of the
conductive polymer include a non-conjugated or conjugated polymer in which an aromatic
carbocycle, an aromatic heterocycle, or a heterocyclic ring is linked through a single bond or a
divalent or higher-valent linking group.
[0043] Examples of the conductive polymer include one or more substituted or unsubstituted
conductive polymers selected from the group consisting of polyaniline, polythiophene,
. polyparaphenylene, polyisothianaphtene, polyparaphenylene vinylene, polyfuran, polypyrrole,
polyselenophene, polyphenylene sulfide, polyacetylene, polypyridylvinylene,
polyethylenedioxythiophene, poly(p-phenylene), and polyazine.
[0044] It is preferable to add, as dopants, for example, one or two selected from the group
consisting of halogens, alkali metals, amino acids, alcohols, camphorsulfonic acid,
dodecylbenzenesulfonic acid, poly(styrenesulfonic acid), and poly(vinylsulfonic acid) to the
conductive polymer that is a conjugated polymer because convenience is enhanced.
Specifically, the addition of such dopants to such conductive polymers that are such
conjugated polymers results in stabilization of a state, improvement in solubility, and
improvement in conductivity.
[0045] The conductive polymer preferably has hydrophilicity. In this case, the conductive
8
polymer layer 131 can be formed using a water-based dispersion liquid of the conductive
polymer.
[0046] Still more preferably, the conductive polymer is PEDOT/PSS. PEDOT/PSS is a
polymer compound composed ofpoly(3,4-ethylenedioxythiophene) (PEDOT) and
poly(styrenesulfonie acid) (PSS).
[0047] Known PEDOT/PSS may be used. Examples of commercially available
PEDOT/PSS include CLEVIOS SERIES from H. C. Starck GmbH, PEDOT-PSS 483095 and
560598 from Aldrich Corporation, and DENATRON SERIES from Nagase Chemtex
Corporation.
[0048] The preferred thickness of the conductive polymer layer 131 is from5 to 650 lllll.
In a case in which the thickness of the conductive polymer layer 131 is excessively small, the
conductivity (current collection efficiency) of the transparent electrode 13 may be deteriorated.
In contrast, in a case in which the conductive polymer layer I 3 I is excessively thick, the light
transmissiveness of the transparent electrode 13 may be deteriorated. Accordingly, in a case
in which the thickness of the conductive polymer layer 131 is Jiom 5 to 650 lllll, the
conductivity (current collection efficiency) and light transmissiveness of the transparent
electrode 13 can be easily enhanced. The lower limit of the conductive polymer layer 13 I is
preferably 10011111, and stillmore preferably 130 run. The upper limit of the conductive
polymer layer I 3 I is preferably 600 mn, and still more preferably 400 nm.
[0049] The thickness of the conductive polymer layer 131 is a value measured by the
following method. A cross section of the transparent electrode 13 is observed at a 20-fold
magnification with a scanning electron microscope (SEM), and the thickness of the
conductive polymer layer 131 located at a center between the carbon fibers 132 is measured.
Such measurement is performed at five places, and the average value of values obtained by
the measurement is regarded as the thickness of the conductive polymer layer I 3 I.
The reason that targets for the measurement of the thickness of the conductive
polymer layer 13 I are the centers between the carbon fibers 132 is because the conductive
polymer layer 13 I is formed to be bowed outward in regions near to the carbon fibers 132 due
to surface tension.
[0050] (Carbon Fibers 132)
The carbon fibers 132 are well-known carbon fibers. The carbon fibers 132 are
produced, for example, by flameproofing or carbonizing acrylic fibers, or by performing
infusible treatment, carbonization, or graphitization from petroleum pitch.
The diameter of the carbon fibers 132 is larger than the thickness of the conductive
polymer layer 131. Therefore, the carbon fibers 132 are partially embedded in the
9
conductive polymer layer 131, as illustrated in Fig. 2. In other words, a part of each carbon
fiber 132 is included in the conductive polymer layer 131 while the remainder of each carbon
fiber 132 is exposed from the conductive polymer layer 131. Specifically, for example, the
plurality of carbon fibers 132 are dotted and arranged so that one radial pmi of each of the
carbon fibers 132 (for example, a part, which is one radial part of each of the carbon fibers
132, of a region from the outer peripheral surface thereof to one-third (preferably to
one-fourth or less) of the diameter thereof) is embedded in the conductive polymer layer 131.
The carbon fibers 132 may be arranged on the conductive polymer layer 131 so that
one carbon fiber 132 overlaps with another carbon fiber 132. In this case, for example, a
pati of the one carbon fiber 132, excluding a region in which the one carbon fiber 132
overlaps with the other carbon fiber 132, and the neighborhood of the region, is in the state of
being embedded in the conductive polymer layer 131.
[0051] The preferred diameter of the carbon fibers 132 is from 2 to 90 times the thickness of
the conductive polymer layer 131. In a case in which the ratio of the diameter of the carbon
fibers 132 to the thickness of the conductive polymer layer 131 is excessively low, the
conductivity of the transparent electrode 13 may be deteriorated. In a case in which the ratio
of the diameter of the carbon fibers 132 to the thickness of the conductive polymer layer 131
is excessively high, the light transmissiveness of the transparent electrode 13 may be
deteriorated. Accordingly, the conductivity (current collection efficiency) and light
transmissiveness of the transparent electrode 13 can be easily enhanced in a case in which the
ratio of the diameter ofthe carbon fibers 132 to the thickness of the conductive polymer layer
131 is from 2 to 90 times. The lower limit of the ratio of the diameter of the carbon fibers
132 to the thickness of the conductive polymer layer 131 is more preferably 18 times, and still
more preferably 35 times. The upper limit of the ratio of the diameter of the carbon fibers
132 to the thickness of the conductive polymer layer 131 is more preferably 84 times, and still
more preferably 60 times.
[0052] Specifically, the preferred diameter of the carbon fibers 132 is from2 to 15 Jlm.
The lower limit of the diameter of the carbon fibers 132 is more preferably 5 Jlm, and still
more preferably 8 Jlm. The upper limit of the diameter of the carbon fibers 132 is more
preferably 13 Jlm, and stillmore preferably 11 Jlm.
[0053] The diameter of the carbon fibers 132 is a value measured by the following method.
Across section of the transparent electrode 13 is observed at a 5000-fold magnification with a
scanning electron microscope (SEM), and the diameters of cross sections perpendicular to the
lengthwise directions of the carbon fibers 132, among the cross sections of the carbon fibers
132, are measured. Such measurement is performed at five places, and the average value of
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values obtained by the measurement is regarded as the diameter of the carbon fibers 132.
In a case in which the carbon fibers 132 can be separately collected, the carbon fibers
132 are directly observed and measured.
[0054) The preferred length of the carbon fibers 132 is from 50 to 7000 ~tm (7 mm). It is
preferable that at least some of the plurality of carbon fibers 132 come in contact with each
other in the transparent electrode !3, as illustrated in Fig. 3. In this case, the conductivity of
the transparent electrode 13 can be easily enhanced.- In a case in which the length of the
carbon fibers 132 is excessively shmi, the number of carbon fibers 132 coming in contact
with each other may decrease, thereby deteriorating the conductivity of the transparent
electrode 13. In contrast, in a case in which the length of the carbon fibers 132 is
excessively long, homogeneous dispersion of the carbon fibers 132 in the transparent
electrode 13 may be precluded, thereby deteriorating the conductivity. Accordingly, the
conductivity of the transparent electrode 13 can be easily enhanced in a case in which the
length of the carbon fibers 132 is from 50 to 7000 fHU. The lower limit of the length of the
carbon fibers 132 is more preferably 2000 f.!m, and stillmore preferably 2500 f.!m. The
upper limit of the length ofthe carbon fibers 132 is more preferably 6500 f.!m, and stillmore
preferably 6000 f.lm.
[0055] The length of the carbon fibers 132 is a value measured by the following method. A
plane of the transparent electrode 13 (a plane closer to a region in which the carbon fibers 132
are disposed) is observed at a 10-fold magnification with an optical microscope, and the
lengths of the carbon fibers 132 are measured. Such measurement is performed at five
places, and the average value of values obtained by the measurement is regarded as the length
of the carbon fibers 132.
In a case in which the carbon fibers 132 can be separately collected, the carbon fibers
132 are directly observed and measured.
[0056] The preferred area rate of the carbon fibers 132 is from 40 to 90% with respect to the
transparent electrode 13. The area rate of the carbon fibers 132 is the percentage of the area
of the carbon fibers occupying the unit area of the transparent electrode 13 (the projection
area of the carbon fibers in the thickness direction of the transparent electrode 13) in the case
of being viewed from a direction perpendicular to the plane of the transparent electrode 13
(the plane closer to the region in which the carbon fibers 132 are disposed). In a case in
which the area rate of the carbon fibers 132 is excessively low, the conductivity of the
transparent electrode 13 may be deteriorated. In a case in which the area rate of the carbon
fibers 132 is excessively high, the light transmissiveness of the transparent electrode 13 may
be deteriorated. Accordingly, the conductivity and light transmissiveness of the transparent
11
electrode 13 can be easily enhanced in a case in which the area rate of the carbon fibers 132 is
from 40 to 90%. The lower limit of the area rate of the carbon fibers 132 is more preferably
45%, and still more preferably 50%. The upper limit of the area rate of the carbon fibers 132
is more preferably 87%, and still more preferably 80%.
[0057] The area rate of the carbon fibers 132 is a value measured by the following method.
A plane of the transparent electrode 13 (a plane closer to a region in which the carbon fibers
132 are disposed) is observed at a 5-fold magnification with an optical microscope, and the
area rate of the carbon fibers 132 in the observed visual field is measured. Such
measurement is performed at five visual fields, and the average value of values obtained by
the measurement is regarded as the area rate of the carbon fibers 132.
[0058] The preferred content of the carbon fibers 132 in the transparent electrode 13 is Ji'om
70 to 98 mass%. In a case in which the content of the carbon fibers 132 is excessively low,
the conductivity of the transparent electrode 13 may be deteriorated. In contrast, in a case in
which the content of the carbon fibers 132 is excessively high, the light transrnissiveness of
the transparent electrode 13 may be deteriorated. Accordingly, the conductivity and light
transrnissiveness of the transparent electrode 13 can be easily enhanced in a case in which the
content of the carbon fibers 132 is fi·om 70 to 98 mass%.
[0059] [Sealing Layer 14]
The sealing layer 14 is a layer that is disposed on the transparent electrode 13, and
seals the substrate electrode 11, the organic functional layer 12, and the transparent electrode
13. The sealing layer 14 is not particularly restricted, and a sealing layer including a
well-known sealing material having high light transmissiveness as well as having durability
(weather resistance, high-temperature resistance, high-humidity resistance, or the like) and
electrical insulation properties is used as the sealing layer 14.
Examples of the sealing material include resin sealing materials such as
ethylene-vinyl acetate copolymer (EVA), polyethylene terephthalate, polyethylene naphthalate,
polyethersulfone, and polycarbonate.
[0060] [Production Method]
An example of a method of producing the organic electronic device 1 and the
transparent electrode 13 will be described.
[0061] The substrate 10, the substrate electrode 11, and the organic functional layer 12 are
produced by a well-known method. For example, first, the substrate 10 is prepared. The
substrate electrode 11 is formed on the substrate 10. The substrate electrode 11 is produced
by a well-known method. In a case in which the substrate electrode 11 is a metallic thin film,
the substrate electrode 11 is formed by a method such as a vapor deposition method or a
12
sputtering method using an electrode material (metal or the like). In a case in which the
substrate electrode 11 is an ITO film, an ITO application liquid is applied onto the substrate.
The ITO application liquid on the substrate is heated at from 400 to 800°C to form the
substrate electrode I I (ITO film).
[0062] After the formation of the substrate electrode 11, the organic functional layer 12 is
formed. The organic functional layer 12 is produced by a well-known method. The
organic functional layer 12 is produced by, for example, a casting method, a spin coating
method, a doctor blade method, a screen printing method, an ink-jet method, a meniscus
method, a die coating method, a gravure printing method, a slide coating method, a spray
method, a flexographic printing method, an electrophotographic method, a vapor deposition
method, or the like.
[0063] After the formation of the organic functional layer 12, the transparent electrode 13 is
formed on the organic functional layer 12. For example, first, a conductive polymer
dispersed liquid is produced. Specifically, a conductive polymer is dispersed in a solvent by
a known method. Examples of the known method include ultracentrifugal grinding methods,
cutting mill methods, disc mill methods, and ball mill methods. Examples of the solvent
include water, alcohols, and ethers. Preferably, the solvent is water.
[0064] The carbon fibers 132 are added to the conductive polymer dispersed liquid, and the
carbon fibers 132 are dispersed in the conductive polymer dispersed liquid. The known
method described above is adopted as a dispersion method. The conductive polymer
dispersed liquid is produced by the above steps.
[0065] An additive may be added to the conductive polymer dispersed liquid. Examples of
the additive include surfactants, dissolution accelerators, plasticizers, antioxidants,
sulfurization inhibitors, and viscosity modifiers.
[0066] Examples of the surfactants include anionic surfactants such as alkyl sulfonic acids,
alkylbenzene sulfonic acids, and alkyl carboxylic acids; cationic surfactants such as primary to
tertiary fatty amines, quaternary ammonium, and tetraalkylanm10niums; zwitterionic
surfactants such as N,N-dimethyl-N-alkyl-N-carboxymethyl anunonium betaine and
N,N,N-trialkyi-N-sulfoalkylene ammonium betaine; and non ionic surfactants such as
polyoxyethylene alkyl ethers, polyoxyethylene alkyl phenyl ethers, and polyoxyethylene
polyst}'IYI phenyl ethers.
[0067] Preferably, dimethylsulfoxide (DMSO) is further added as an additive in the case of
using PEDOT/PSS as the conductive polymer. DMSO fhrther enhances the conductivity of
PEDOT/PSS.
[0068] The conductive polymer dispersed liquid is prepared by the above steps.
13
[0069] In a case in which the content of the carbon fibers in the conductive polymer
dispersed liquid is high, the light transmissiveness of the transparent electrode 13 may be
deteriorated. Accordingly, the preferred content of the carbon fibers is 2.5 mass% or less.
In contrast, in a case in which the content of the carbon fibers in the conductive polymer
dispersed liquid is excessively low, the conductivity of the transparent electrode 13 may be
deteriorated. Accordingly, the lower limit of the content of the carbon fibers in the
conductive polymer dispersed liquid is preferably 1.0 mass%, and stillmore preferably 1.5
mass%.
[0070] In the case of adding a surfactant to the conductive polymer dispersed liquid, the
excessively high content of the surfactant in the conductive polymer dispersed liquid may
result in deterioration of the conductivity of the transparent electrode 13. Accordingly, the
preferred content ofthe surfactant is 2.5 mass% or less. The preferred lower limit of the
content of the surfactant is 0.1 mass%.
[0071] In the case of adding DMSO to the conductive polymer dispersed liquid, the
excessively high content of DMSO in the conductive polymer dispersed liquid results in
saturation of the effect of improvement in conductivity. Accordingly, the preferred content
ofDMSO is 15 mass% or less. The preferred lower limit of the content ofDMSO is 5
mass%.
[0072] Then, the prepared conductive polymer dispersed liquid is applied onto the organic
functional layer 12. Specifically, the conductive polymer dispersed liquid is applied onto the
organic functional layer 12 using, for example, spin coating, casting, an extrusion die coater, a
bread coater, an air doctor coater, a knife coater, an applicator, or the like. As a result, a
coating film of the conductive polymer dispersed liquid is produced. In the case of
producing the film using the applicator, the preferred thickness of the coating film of the
dispersion liquid is fi·om 0.5 MIL to 7 MIL (1 MIL= 12.5 f!m).
[0073] After the production of the film, the coating film of the dispersion liquid is dried to
form the transparent electrode 13. A drying method is not particularly limited. For
example, the drying is performed at a temperature of 120°C or less for a predetermined time.
The preferred drying time is from 20 seconds to 30 minutes. However, the drying time is not
limited thereto. For example, a hot plate, an oven, a hot-blast stove, or the like can be used
in the drying step.
[0074] Then, the sealing layer 14 is formed on the transparent electrode 13 utilizing a
well-known method, to seal the substrate electrode 11, the organic functional layer 12, and the
transparent electrode 13.
[0075] The organic electronic device 1 and the transparent electrode 13 are produced by the
14
above production steps. The transparent electrode 13 can be easily produced by applying
and drying the dispersion liquid. Because the transparent electrode 13 is formed by the
drying, it is not necessary to heat the coating film of the dispersion liquid to a high
temperature of 400°C or more as in the case of the ITO film. Therefore, the transparent
electrode 13 can be easily produced even on the organic functional layer 12 having poor heat
resistance.
[0076] The embodiment in which the transparent electrode 13 is formed by the
above-described production method using the conductive polymer dispersed liquid to which
the carbon fibers 132 are added is described. However, a method of forming the transparent
electrode 13 is not limited thereto. For example, the transparent electrode 13 may be formed
by applying a conductive polymer dispersed liquid that does not contain any carbon fiber 132
onto the organic fi.mctionallayer 12 to form a film, then sprinkling the carbon fibers 132 on
the coating film of the conductive polymer dispersed liquid, and dtying the film.
[0077] It is preferable to apply a conductive polymer dispersed liquid mixed with the carbon
fibers 132 onto the organic fi.mctionallayer 12 to form the transparent electrode 13. In this
case, the conductive polymer easily enters pmiions between the carbon fibers 132 even in a
case in which the carbon fibers 132 are arranged, thereby vetiically overlapping each other.
Therefore, the conductivity of the transparent electrode 13 can be easily enhanced.
[0078] The transparent electrode 13 may be formed on the substrate 10 rather than on the
organic functional layer 12. Even in the case of forming the transparent electrode 13 on the
substrate 10, a method of producing the transparent electrode 13 is the same as the
above-described method.
[0079] Examples of the organic electronic device 1 include solar cells, light -emitting
elements (organic electroluminescence elements and the like), imaging elements (image
sensors and the like), transistors, and displays. The transparent electrode 13 can be utilized
not only as such organic electronic devices 1 but also as a transparent electrode in an
inorganic electronic device having an inorganic fi.mctionallayer.
[0080]
A solar cell module 2 according to the embodiment includes a coated metal substrate
lOA, and a plurality of cell stmctures (single cells) 15 arranged on the coated metal substrate,
as illustrated in Fig. 4. The solar cell module 2 also includes a sealing layer which is not
illustrated, and seals the cell structures (single cells) 15. Ea~h cell structure 15 includes a
substrate electrode 11, an electricity generation unit 12A that is mTanged on the substrate
electrode 11, and a transparent electrode 13 that is arranged on the electricity generation unit
12A. In each cell structure (single cell) 15, a portion in which all of the substrate electrode,
15
the electricity generation unit, and the transparent electrode overlap each other is an electricity
generation place (electricity generation region).
[008 I] In the solar cell module 2, the transparent electrode I 3 of one cell structure I 5
adjacent to another cell structure 15 is connected to the substrate electrode I I of the other cell
structure I 5, whereby connections between the plurality of cell structures 15 are formed to
modularize the cell structures 15. The connections (wiring) between the plurality of cell
structures 15 are formed, for example, by allowing the substrate electrodes I I and transparent
electrodes 13 of the cell structures 15 adjacent to each other to overlap each other.
[0082] In general, for example, the voltages of cell structures (single cells) used in solar
cells are around 1 V. However, for example, the voltages of cell structures (single cells)
including organic thin films used in organic thin-film solar cells (OPV) are 1 V or less.
Therefore, connection between a plurality of cell structures (single cells) and an increase in
final output voltage are required for achieving practical utilization of an organic thin-film
solar cell. In order to increase the final output voltage, the plurality of cell structures (single
cells) are connected, thereby obtaining a module. In general, the power conversion
efficiency of a solar cell module is calculated and evaluated by dividing an electric-generating
capacity by a total area irradiated with light, and therefore, a smaller connection (wiring) area
is preferable. Thus, the wiring area can be reduced in a case in which a plurality of cell
structures (single cells) can be produced on the same substrate. Therefore, it is effective to
modularize organic thin-film solar cells.
[0083] The solar cell module 2 is an example of a device obtained by modularizing the
organic electronic device 1 in which the coated metal substrate 1 OA is used as the substrate,
and the electricity generation unit 12A is used as the organic functional layer 12. In other
words, the organic electronic device 1 may be a device obtained by arranging a plurality of
structures including the substrate electrode 11, the organic functional layer 12, and the
transparent electrode 13 on the substrate 10, and by modularizing the structnres.
[0084] The details of each component of the solar cellmodnle 2 will be described below.
[0085] [Coated Metal Substrate 1 OA]
The coated metal snbstrate lOA includes, for example, a base metal sheet IO!Asuch
as a steel sheet, and a coated layer I 02A formed by applying a coating to a surface of the base
metal sheet lOlA. Fig. 4 illustrates an example in which the coated layer 102Ais disposed
only on one surface of the base metal sheet 10 I A. However, coated layers 1 02A may be
disposed on both surfaces of the base metal sheet 101 A. In the case of disposing the coated
layer 1 02A only on one smface of the base metal sheet 10 lA, the cell shuctures I 5 are formed
on the surface of the coated metal substrate lOA, on which the coated layer 102Ais disposed.
16
[0086] In the case of using a metal sheet having conductivity as the substrate, avoidance of
direct contact of the substrate electrode with the substrate having conductivity is required for
configuring a module by the plurality of cell structures (single cells) 15 formed on the
substrate. The use of the coated metal substrate 1 OA including the coated layer 1 02A having
an insulating property on a side facing the substrate electrode II makes it possible to easily
obtain the solar cell module 2 in which the plurality of cell structures 15 are disposed on one
coated metal substrate I OA.
[0087] The coated metal substrate I OA is preferably a coated metal substrate which includes
the coated layer 1 02A including one or more coating films on one surface or both surfaces of
the base metal sheet I 01 A, and in which a value of the arithmetic mean roughness Ra of a
surface of the coated layer 102A is 20 mn or less, the minimum value of a dynamic storage
elastic modulus in the rubber-like elastic region of an outermost layer of the coated layer
102A is 2 x 109 Pa or less, the total film thickness of the coated layer 1 02A is from I to 30 [!ill,
and a leakage current value during application of a voltage of 100 Vis less than 10·6 A/cm2
•
In a case in which the coated layer 1 02A includes one coating film, the outermost
layer of the coated layer 1 02A corresponds to the coating film. In a case in which the coated
layer 1 02A includes two or more coating films, the outermost layer of the coated layer 1 02A
conesponds to a coating film located on an outermost surface of the coated layer 1 02A.
[0088] In a case in which the coated lay~r 1 02A includes two or more coating films, the
physical propetties of the coating film of the outermost layer influence the properties of the
coated metal substrate 1 OA and the solar cell module including the coated metal substrate 1 OA,
as described below. Thus, the coated layer 1 02A is specified primarily in relation to the
coating film of the outermost layer.
[0089] A surface of the coated layer 1 02A preferably has an arithmetic mean roughness Ra
value of20 nm or less, and more preferably has an aritlnnetic mean roughness Ra value of20
run or less, and a total roughness Rz value of a maximum peak height Rp and a maximum
valley depth Rv, of200 nm or less. In a case in which the outermost layer has a Ra of20 mn
or more, it may be difficult to sufficiently flatten the concavities and convexities of a surface
of the coated metal substrate, thereby deteriorating electrical performance. In a case in
which the coating film of the outermost layer has an Rz value of more than 200 mn, pinholes
may be generated in the substrate electrode 11 formed on the coated metal substrate I OA,
thereby causing a short circuit, even in the case of an Ra of20 mn or less.
[0090] A numerical value of the surface roughness of the coated layer 102A is known to
vary according to a measurement method. Therefore, the arithmetic mean roughness Ra, and
the total rouglmess Rz of a maximum peak height Rp and a maximum valley depth R v are
17
defined as values calculated based on a roughness curve measured from an image obtained by
imaging the surface geometry of the coated layer I 02A using an atomic force microscope
(AFM).
[0091) The total film thickness of the coated layer I 02A is preferably from 1 to 30 pm, and
more preferably from 5 to 20 ;tm. The insulating property of the coated layer 102A may be
deteriorated in a case in which the total film thickness is less than 1 pm. A disadvantage
may occur in view of a cost in a case in which the total film thickness is more than 20 ;tm.
[0092) The total film thickness of the coated layer 102Ais a value measured by observing a
cross section of the coated layer 102A. Specifically, the coated metal substrate lOA is
embedded in an ordinary temperature drying type epoxy resin perpendicularly to the thickness
direction of the coated layer 102A, and a surface in which the coated metal substrate lOA is
embedded is mechanically polished. The polished surface is observed at a magnification of
5000 with a scanning electron microscope (SEM), and the coated layer I 02A is measured.
Such measurement is performed at five places, and the average value of values obtained by
the measurement is regarded as the total film thickness of the coated layer I 02A.
[0093) It is preferable that the coated layer I 02A has the function of reducing thermal stress
generated due to a difference between the coefficients of thennal expansion of both of the
coated metal substrate I OA and each cell stmcture 15 formed on the coated metal substrate
I OA (particularly, each substrate electrode II coming in contact with the coated metal
substrate I OA, in the cell structures 15). In other words, it is preferable that the coated layer
1 02A allows interface stress between each substrate electrode 11 and the coated metal
substrate 1 OA to be reduced, thereby reducing strain energy accumulated in a case in which a
heat history is given to the formed cell shuctures 15.
In the solar cell module in which the cell structures 15 can be produced at low
temperature, it is preferable that the coated layer I 02A has the above-described function in
order to obtain the higher reliability of the solar cell module although the generation of
thermal stress is precluded due to the difference between both the coefficients of thermal
expanston.
[0094) Such strain energy is commonly accumulated in the coated layer 102A, and can be
reduced by the viscoelastic properties of a primary resin included in the coated layer I 02A.
In the coated layer 1 02A, the primary resin is not particularly limited. For example, in a
case in which the primmy resin is a thermosetting resin having a cross-linked structure, the
strain energy depends on a molecular weight between cross-links, and the molecular weight
between cross-links commonly correlates with the equilibrium elasticity modulus of the
rubber-like elastic region of the resin.
18
[0095] A resin that is a viscoelastic body has an elasticity modulus varying depending on a
temperature and a time (a frequency in the case of a dynamic storage elastic modulus). A
cross-linked thermosetting resin indicates a high elasticity modulus (commonly a value of
from around 109 to 10 10 Pa) in a low-temperature or short-time (high-frequency in the case of
a dynamic storage elastic modulus) region (the region is commonly referred to as a glass-like
elastic region). A region in which an elasticity modulus sharply decreases according to
higher temperature or a longer time (a lower frequency in the case of a dynamic storage
elastic modulus) appears (the region is commonly referred to as a transition region). In
addition, the equilibrium elasticity modulus becomes constant at high temperature or a long
time (low frequency in the case of a dynamic storage elastic modulus), and the equilibrium
elastic region in this case is referred to as a rubber-like elastic region (commonly indicating a
value of from around 106 to 108 Pa).
[0096] The property of the coating film is defined by the minimum value of dynamic storage
elastic modulus appearing in a high-temperature rubber-like elastic region, in dynamic storage
elastic modulus measured in a region at a constant frequency (angular frequency of 6.28
rad/sec) and a temperature of from -50 to 200°C by a dynamic viscoelasticity measuring
apparatus. A dynamic storage elastic modulus is coll1tllonly represented by E', and defined
byE' = ( aO!yO) cos 8. Herein, aO represents the maximum amplitude of stress, yO represents
the maximum amplitude of strain, and 8 represents a phase angle between the stress and the
strain.
[0097] The minimum value of dynamic storage elastic modulus in the rubber-like elastic
region of the outermost layer of the coated layer I 02A is preferably 2 x 109 Pa or less, and
more preferably 2 x 107 Pa or less. This is because the molecular weight between
cross-links of the primary resin of the outermost layer of the coated layer 102Amay become
small, and elastic strain energy accumulated in the coated layer 1 02A (outermost layer
thereof) in a case in which the coated layer 1 02A receives thermal stress may become large, in
a case in which the minimum value of the dynamic storage elastic modulus is more than 2 x
109 Pa. In other words, this is because even in a case in which the appearance of the coated
layer I 02A is unproblematical immediately after the formation of the cell structures 15, the
coated layer 1 02A (outermost layer thereof) may be broken or peeled in a case in which the
coated layer I 02A receives a heat history.
[0098] It is preferable that the coated metal substrate 1 OA has a leakage current value ofless
than 1 o-6 A/cm2 in the case of applying a voltage of 100 V. It is necessary that the coated
metal substrate lOA has insulating propetiies for inhibiting deterioration of electrical
performance due to conduction between the electricity generation unit 12A including an
19
~I
electricity-generating layer and the like as a photoelectric conversion layer 12 I, and the base
metal sheet 10 !A. It may be difficult to secure the quality of the electricity generation unit
12A in a case in which the leakage current value is 10·6 A/cnl or more.
[0099] The primary resin of the coated layer I 02A is not particularly limited, and examples
thereof include polyester resin, epoxy resin, urethane resin, acrylic resin, melamine resin, and
fluorine resin. The primary resin of the coated layer I 02A is preferably a thermosetting resin
in a case in which the primary resin is used in applications in which severe processing is
performed. Examples of the thermosetting resin include polyester resins (epoxy polyester
resin, polyester resin, melamine polyester resin, urethane polyester resin, and the like), and
acrylic resins. The polyester resins and the acrylic resins are superior in processability to
other resins, and inhibit the coated layer 102A from being cracked even after severe
processmg.
[0 I 00) The primary resin of the outermost layer of the coated layer I 02A is not particularly
limited, and is preferably a polyester resin. The polyester resin is not particularly limited,
and is preferably a commonly known ester compound of a polybasic acid and a polyhydric
alcohol, which compound is synthesized by a commonly known esterification reaction.
[0101] The polybasic acid is not particularly limited, and examples thereofinclnde phthalic
acid, isophthalic acid, terephthalic acid, phthalic anhydride, trimellitic anhydride, maleic acid,
adipic acid, and fumaric acid. These polybasic acids may be used singly, or in combination
of plural kinds thereof.
[0102] The polyhydric alcohol is not particularly limited, and examples thereof include
ethylene glycol, diethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol,
polypropylene glycol, neopentylene glycol, I ,4-butanediol, 1,5-pentanediol, I ,6-hexanediol,
1,4-cyclohexanedimethanol, polytetramethylene ether glycol, glycerin, trimethylolethane,
trimethylolpropane, trimethylolbutane, hexanetriol, pentaerytln'itol, and dipentaerytln·itol.
These polyhydric alcohols may be used singly, or in mixture of hvo or more kinds thereof.
[0103] In a case in which such a polyester resin is used, it is preferable to blend the polyester
resin with a curing agent because the hardness of the coated layer l 02A is improved. As the
curing agent, which is not particularly limited, either a commonly known amino resin or
polyisocyanate compound, or both thereof are used.
[0104] The amino resin is not particularly limited, and examples thereof include resins
obtained by reaction of urea, benzoguanamine, melamine, and the like with formaldehyde,
and resins obtained by alkyl-etherifYing urea, benzoguanamine, melamine, and the like with
an alcohol. Specific examples of the amino resin include methylated urea resin, n-butylated
benzoguanamine resin, and melamine resins (methylated melamine resin, n-butylated
20
melamine resin, iso-butylated melamine resin, and the like).
[0 I 05] Examples of resins widely used in the field of the coated metal substrate 1 OA include
a polyester/melamine resin in which a polyester resin as a primary resin, and a melamine resin
as a curing agent are used. Examples of melamine resins as used herein include at least one
or more of methylated melamine resin, n-butylated melamine resin, or iso-butylated melamine
resm.
[0 I 06] The polyisocyanate compound is not particularly limited, and preferred examples
thereof include isocyanate compounds blocked with blocking agents such as phenol, cresol,
aromatic secondary amines, tertiary alcohols, lactam, and oxime. Stillmore preferred
examples of the polyisocyanate compound include hexamethylene diisocyanate (HDI) and
derivatives thereof, tolylene diisocyanate (TDI) and derivatives thereof, diphenylmethane
diisocyanate (MDI) and derivatives thereof, xylylene diisocyanate (XDI) and derivatives
thereof, isophorone diisocyanate (IPDI) and derivatives thereof, trimethylhexamethylene
diisocyanate (TMDI) and derivatives thereof, hydrogenated TDI and derivatives thereof,
hydrogenated MDI and derivatives thereof, and hydrogenated XDI and derivatives thereof.
[0 I 07] The configuration of the coated layer I 02A is not particularly limited, and it is
preferable for enhancing the corrosion resistance of the cell shuctures 15 that the coated layer
I 02A is a layer in which at least one coating film contains a mst preventive pigment, in a case
in which the coated layer I 02A is a multilayer including two or more coating films.
[0 1 08] The mst preventive pigment is not patticularly limited, and examples thereof include
known chromate-free mst preventive pigments such as phosphate-based rust preventive
pigments (zinc phosphate, iron phosphate, aluminum phosphate, zinc phosphite, aluminum
tri-polyphosphate, and the like), molybdate-based rust preventive pigments (such as calcium
molybdate, aluminum molybdate, and barium molybdate), vanadium-based rust preventive
pigments (vanadium oxide and the like), silicate-based rust preventive pigments (calcium
silicate and the like), silica-based rust preventive pigments (water-dispersed silica, finned
silica, calcium ion exchanged silica, and the like), ferroalloy-based rust preventive pigments
(ferrosilicon and the like); and known chromium-based rust preventive pigments such as
strontium chromate, potassium chromate, barium chromate, and calcium clu·omate. From
the viewpoint of environmental preservation in recent years, a chromate-free rust preventive
pigment is preferable as the rust preventive pigment. These rust preventive pigments may be
used singly, or in combination of plural kinds thereof.
[0 I 09] The amount of added rust preventive pigment is preferably fi·om I to 40 mass% with
respect to the solid content standard of a coating film. In a case in which the amount of
added rust preventive pigment is less than 1 mass%, corrosion resistance may be
21
insufficiently improved. In a case in which the amount of added rust preventive pigment is
more than 40 mass%, processability may be deteriorated, whereby a coating film may fall off
during processing, and corrosion resistance tends to be also poor.
[0 11 0] It is preferable that the coated metal substrate I OA is a coated metal substrate that is a
product shipped to consumers in a state in which the coated layer 1 02A is formed on the base
metal sheet I 01 A. Examples of such coated metal substrates 1 OA include a coated metal
substrate in which the coated layer 1 02A is formed by coating the base metal sheet 10 !A with
a coating, and a coated metal substrate in which the coated layer I 02A is formed by
laminating a resin film on the base metal sheet lOlA. These coated metal substrates lOA
have merits that are not possessed by post -coated metal sheets coated after processing.
Examples of the merits include possible omissi oil of coating steps in consumers, possible
solution of public nuisance and envirolll11ental problems caused by coating waste and the like,
and possible conversion of space for coating into other applications.
[0111] In the coated metal substrate lOA, a conversion treatment layer (not illustrated) may
be disposed between the base metal sheet lOlA and the coated layer 102A, if necessary. The
conversion treatment layer is disposed for the purposes of, e.g., enhancing adhesiveness
between the base metal sheet lOlA and the coated layer 102A, and improving corrosion
resistance. Examples of conversion treatments for forming the conversion treatment layer
include known treatments such as zinc phosphate treatment, chromate treatment, silane
coupling treatment, composite oxidation fihn treatment, chromate-free treatment, tannic
acid-based treatment, titania-based treatment, zirconia-based treatment, Ni surface
conditioning treatment, Co surface conditioning treatment, and mixed treatments thereof. Of
the conversion treatments, chromate-fi'ee treatment is preferable fi·om the viewpoint of
enviromnental preservation.
[0 112] In the coated metal substrate I OA, the base metal sheet I 01 A is not particularly
limited, and examples thereof include metal sheets of iron, iron-based alloys, aluminum,
aluminum-based alloys, copper, copper-based alloys, and the like. Examples of the base
metal sheet lOlA also include a plated metal sheet including an optional plated layer on a
metal sheet. Of these metal sheets, the base metal sheet lOlA is most preferably a metal
sheet (steel sheet) including a zinc-based plated layer or an aluminum-based plated layer.
[0113] Examples of the zinc-based plated layer include galvanized layers, zinc-nickel plated
layers, zinc-iron plated layers, zinc-chromium plated layers, zinc-aluminum plated layers,
zinc-titanium plated layers, zinc-magnesium plated layers, zinc-manganese plated layers,
zinc-aluminum-magnesium plated layers, and zinc-aluminum-magnesium-silicon plated
layers. Further examples of the zinc-based plated layer also include plated layers obtained
22
by allowing the plated layers to contain cobalt, molybdenum, tungsten, nickel, titanium,
clu-omium aluminum, manganese, iron, magnesium, lead, bismuth, antimony, tin, copper,
cadmium, arsenic, and the like as small amounts of different metal elements or impurities, and
plated layers in which inorganic substances such as silica, alumina, and titania are dispersed.
[01 14] Examples of the aluminum-based plated layer include aluminum plated layers, and
plated layers of alloys of aluminum and at least one of silicon, zinc, or magnesium (for
example, aluminum-silicon plated layers, aluminum-zinc plated layers,
aluminum-silicon-magnesium plated layers, and the like).
[01 I 5] A metal sheet including a multilayered plated layer in which a zinc-based plated layer
or an aluminum-based plated layer, and another kind of plated layer (for example, iron plated
layer, iron-phosphorus plated layer, nickel plated laye1~ cobalt plated layer, or the like) are
layered one on another can be used as the base metal sheet I 01 A.
[0 I 16] The plating method is not particularly limited. As the plating method, any method
of known electroplating methods, hot-dip plating methods, vapor deposition plating methods,
dispersion plating methods, vacuum plating methods, or the like is acceptable.
[0117] [Electricity Generation Unit 12A]
The electricity generation unit 12A includes an electricity-generating layer as the
photoelectric conversion layer 121. Specifically, the electricity generation unit 12A includes,
for example, the electricity-generating layer as the photoelectric conversion layer 121, the
electron transport layer 122 disposed on a side, closer to the substrate electrode II, of the .
electricity-generating layer, and the hole transport layer 123 disposed on a side, closer to the
transparent electrode 13, of the electricity-generating layer (see Fig. 1). The electron
transport layer 122 and the hole transport layer 123 are layers disposed, ifnecessmy. The
electricity generation unit 12A may include a layer other than the above-described layers, for
example, a hole injection layer, an electron injection layer, an insulating layer, an
antireflection layer, or the like.
[01 18] The electricity-generating layer includes, for example, an organic semiconductor.
The electricity-generating layer including an organic semiconductor can be produced by a
method by which a film can be formed at low temperature (for example, a spin coating
method or the like), rather than by a costly method such as vapor deposition.
[0 119] Examples of the organic semiconductor include optional electron-donating p-type
organic semiconductors and optional electron-accepting n-type organic semiconductors.
Such a p-type organic semiconductor is not pmiicularly limited, and examples
thereof include organic compounds such as P3HT (poly(3-hexylthiophene-2,5-diyl)),
thiophene, phenylenevinylene, thienylene vinylene, carbazole, vinylcarbazole, pyrrole,
23
isothianaphene, and heptadiene. Examples of the organic semiconductor also include
polymers of the organic compounds and derivatives having, e.g., at least one group selected
from the group consisting of hydroxyl, alkyl, amino, methyl, nitro, and halogen groups.
Such p-type organic semiconductors may be used singly, or in combination of two or more
kinds thereof.
Examples of such n-type organic semiconductors include PCBM ([6,6]-phenyl C6l
butyric acid methyl ester), fullerene derivatives, and perylene derivatives. Of these n-type
organic semiconductors, fullerene derivatives are particularly preferable because electrons
especially rapidly transfer from a p-type organic semiconductor. Examples of such fullerene
derivatives include derivatives of fullerene C60, derivatives of fullerene C70, and derivatives
of fullerene CSO. As then-type organic semiconductors, commercially available products
can be used. For example, a product manufactured by Sigma-Aldrich Co. LLC. or Frontier
Carbon Corporation can be used as P3HT/PCBM.
[0120] The electron transpmi layer 122 includes an electron transpoti material. Examples
of the electron transport material include zinc acetate, zinc(II) acetylacetonate, titanium
isopropoxide, and titanium oxysulfate.
The hole transpmi layer 123 includes a hole transport material. Examples of the
hole transport material include PEDOT/PSS, and metal oxides such as molybdenum oxide,
nickel oxide, and tungsten oxide.
[0121] The film thickness of each layer included in the electricity generation unit 12A is not
particularly limited, and may be determined in consideration of performance and a cost. For
example, the film thickness of the electricity-generating layer is preferably from 50 to 400 tml,
and more preferably from 100 to 300 lll11. The film thicknesses of the electron transport
layer 122 and the hole transport layer 123 are preferably from 80 to 300 nm, and more
preferably from 100 to 250 lll11.
[0122] [Others]
The configuration of the substrate electrode II, the transparent electrode 13 as an
upper electrode, and the sealing layer in the solar cell module is similar to that of the substrate
electrode II, the transparent electrode 13, and the sealing layer 14 described in the organic
electronic device. Therefore, explanations thereof are omitted.
[0123] [Production Method]
The solar cell module 2 can be produced according to the method of producing the
organic electronic device I.
Examples of production of the solar cell module 2 in which the plurality of cell
structures 15 (single cells) are linked onto the coated metal substrate lOA include I) a
24
procedure of producing a plurality of cell structures 15 on individual coated metal substrates
I OA and connecting corresponding electrodes, 2) a procedure of forming a plurality of cell
structures 15 on one coated metal substrate lOA and connecting the cell structures 15. For
example, a method of producing films in belt shapes in the order of a substrate electrode II,
an electricity generation unit 12A, and a transparent electrode 13 on a coated metal substrate
I OA is often adopted for producing the solar cell module 2 having the latter structure by a
continuous process.
EXAMPLES
[0124] Examples which are examples of the invention will be described. The examples
exemplify the invention, and are not intended to limit the invention.
[0125]
Transparent electrodes oftest numbers I to 57 shown in Table I to Table 3 were
produced, and the sheet resistance values (Q/sq) and light transmittances(%) of the
transparent electrodes were investigated.
[0126] The transparent electrodes of the test numbers 1 to 22 were produced by the
following method. Glass substrates were prepared. Then, conductive polymer dispersed
liquids were prepared. As such a conductive polymer dispersed liquid, a PEDOT/PSS
dispersion liquid (CLEVIOS P HC V 4 (trade name) from H.C. Starck GmbH) was used.
The solid content concentration ofPEDOT/PSS in the dispersion liquid was 1.3 mass%.
DMSO (manufactured by Aldrich Corporation) and a surfactant (denoted by "SF" (TRITON
X-100 (trade name) manufactured by Aldrich Corporation) in Table 1 to Table 3) were added
to the PEDOT/PSS dispersion liquid, if necessary. The details of the compositions of the
dispersion liquids are shown in Table 1.
[0127] The prepared conductive polymer dispersed liquids were applied onto the glass
substrates by a doctor blade method, whereby coating films were formed. Then, the coating
films were dried at 120°C for 20 minutes, to produce the transparent electrodes. The
thickness of the conductive polymer layer of each transparent electrode was in a range of from
13 0 to 600 lllll.
[0128] In the test numbers 23 to 57, carbon fibers (denoted by "CF" in Table I to Table 3)
were added in addition amounts (percentages [mass%] in a case in which the components of
the conductive polymer dispersion liquids excluding the carbon fibers were regarded as 1 00)
shown in Table 2 to the conductive polymer dispersed liquids described above. The carbon
fibers used are as follows. The details of the compositions of the dispersion liquids are
shown in Table 2 to Table 3.
25
·Test numbers 23 to 42: GRANOC CHOPPED FIBER (trade name) manufactured by
Nippon Graphite Fiber Corporation (diameter= II 11m, length= 3 nun)
·Test numbers 43 to 57: GRANOC MILLED FIBER (trade name) manufactured by
Nippon Graphite Fiber Corporation (diameter= II 11m, length = 6 mm)
[0129] The conductive polymer dispersed liquids containing the carbon fibers were applied
onto glass substrates by a drop-casting method, whereby coating films of the dispersion
liquids were formed. Then, the coating films of the dispersion liquids were dried at 120°C
for 20 minutes, to produce transparent electrodes. Observation of cross sections of the
transparent electrodes of the test nnmbers 23 to 57 with SEM showed that a pmi of each
carbon fiber was embedded in a conductive polymer layer (PEDOT/PSS film) wllile the
remainder was exposed from the conductive polymer layer.
[0 130] The thicknesses of the conductive polymer layers of the prodnced transparent
electrodes were measured according to the previously explained method, as shown in Table I
to Table 3. Measurement of the carbon fibers (CF) of the transparent electrodes according to
the previously explained method provided the area rates of the carbon fibers (CF) as shown in
Table I to Table 3.
[0 131] [Measurement of Content of Carbon Fibers]
The contents (mass%) of the carbon fibers (CF) in the produced transparent
electrodes were determined by the following method. First, the light transmittances of the
transparent electrodes were measured by a method described later. The masses of the carbon
fibers were calculated from the light transmittances, and the contents (mass%) of the carbon
fibers in the transparent electrodes were determined from the masses of the conductive
polymer layers, separately calculated from the measured thicknesses of the conductive
polymer layer. The measurement results are shown in Table I to Table 3.
[0132] [Test of Measuring Sheet Resistance Value]
The sheet resistance (0/sq) of the transparent electrode of each test number was
determined by the following method. Specifically, the sheet resistance value was measured
by a four-terminal four-point probe method using a LORESTA-GP MCP-T601 TYPE
manufactured by Mitsubishi Chemical Analytech Co., Ltd.
[0133] [Test of Measuring Light Transmittance]
The light transmittance(%) of the transparent electrode of each test number was
measured using a spectrophotometer (VARIAN CARY 4000 (trade name)) manufactured by
Agilent Technologies. Inc.
[0134] The details of each test are listed in Table I to Table 3. The differences between the
sheet resistance values and light transmittance of test numbers of which the compositions of the
26
conductive polymer dispersed liquids or the conductive polymer dispersed liquids containing
carbon fibers (CF), and the thicknesses of the conductive polymer layers are the same (for
example, test numbers 1 and 2, or test numbers 23 and 24) are caused by a lot-to-lot
difference.
[0135]
[Table I]
27
VUIII)JU;:)~liUII \11~~~;:)10) Of f"l"'\nrliJf':thtP
Test PEDOT/PSS r:~
Number d. .
Thickness (nm) of
conductive polymer
layer
CF
Diameter Diameter Length Content A t (o/c)
Sheet resistance
value (Q/sq)
7
8
ISperSIOn
~
94.5 5 0.5 0
94.5 5 0.5 0
94.5 5 0.5 0
94.5 5 0.5 0
_2_ I o.s
94.5 5
33
163
<7
<7
135
135
(~m) ratio (times) (mm) (mass%) rea rae '
- - - - - 206
- - - - - 193
- - - - - 153
- - - - - 129
- - - - - 59
- - - - - 67
- - - - . - 1308
- - - - - 783
- - - - - 257
- - - - - 410
L I I I ,;j''1',V I v I u.v u I u - - - - - 1899
12 + 94.5 -1- 5 + 0.5 0 16 - - - - - 2646
).5 0 81 - - - - - 963
16
17
18
19
94
94.5
94.5
94.5
94.5
94.5
94:5
94.5
5
0.5 0 81 - - - - - 1290
).5 --:0-r--- 228 - - - - - 1049
n8 - - - - - 7~
0.5
0
0
41 - - - - - 269
41 - - - - - 337
203 - - - - - 166
203 - - - - - 179
569 - - - - - 103
569 - - - - - - - - 101
28
Light
transmittance
(%)
90.7
90.3
89.2
89.4
99.8
97.9
98.7
97.3
1.3
1.1
0.(
99.3
98.9
99.0
100.1
3.3
95.5
2.3
82.6
Remarks
c
r.
Comparative
c
Cl
c
L:::::::J:l lU
[0136]
[Table 2]
Composition (mass%) of CF-containing conductive
Test oolvmer disoersed liouid
number PEDOT/PSS DMSO SF CF
dispersion
liquid
23 94.5 5 0.5 2
24 94.5 5 0.5 2
25 94.5 5 0.5 1.5
26 94.5 5 0.5 1.5
27 94.5 5 0.5 2
28 94.5 5 0.5 2
29 94.5 5 0.5 2.5
30 94.5 5 0.5 2.5
31 94.5 5 0.5 1.7
32 94.5 5 0.5 1.7
33 94.5 5 0.5 2.2
34 94.5 5 0.5 2.2
35 94.5 5 0.5 1.5
36 94.5 5 0.5 1.5
37 94.5 5 0.5 2
38 94.5 5 0.5 2
39 94.5 5 0.5 1
40 94.5 5 0.5 1
41 94.5 5 0.5 1.5
- 42 94,5 5 0.5 1.5
Thickness (nm) of
conductive Diameter
polymer layer (~m)
130 11
130 11
200 11
200 11
200 11
200 11
200 11
200 11
300 11
300 11
300 11
300 11
400 11
400 11
400 11
400 11
600 11
600 11
600 11
600 11
!. :.c::::t:l :J
Transoarent electrode
CF
Sheet Ught Remarks
Diameter Length Content Area rate resistance transmittance
ratio (times) (mm) (mass%) (%) value (0/sq) (%)
84.6 3 96.1 62 85 91.8 Exam ole
84.6 3 96.1 62 59 77.6 Example
55.0 3 92.3 69 23 89.9 Exam ole
55.0 3 92.3 69 59 81.1 Example
55.0 3 94.1 62 74 81.6 Exam ole
55.0 3 94.1 62 19 81.6 Example
55.0 3 95.3 58 20 79.0 Exam ole
55.0 3 95.3 58 12 80.7 Example
36.7 3 90.1 65 12 76.4 Exam ole
36.7 3 90.1 65 12 75.6 Example
36.7 3 91.5 60 12 81.1 Example
36.7 3 92.2 60 15 70.5 Example
27.5 3 85.8 69 23 79.2 Example
27.5 3 85.8 69 21 79.8 Example
27.5 3 88.9 62 10 74.8 Examole
27.5 3 88.9 62 11 77.7 Example
18.3 3 72.8 80 14 77.5 Exam ole
18.3 3 72.8 80 17 79.2 Example
18.3 3 80.0 69 12 77.3 Exam ole
18.3 3 80.0 69 12 76.7 Example
29
[0137]
[Table 3]
Test
number
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
Composition (mass%) of CF-
An organic thin-film solar cell (OPV) described below was produced in Example B.
· OPV of Example B 1: OPV including, as an upper electrode, a transparent electrode
including carbon fibers (CF) and a PEDOT/PSS film (hereinafter also abbreviated as
"PEDOT/PSS + CF film")
·OPV of Comparative Example: OPV in which the upper electrode ofOPV of
Example B 1 is replaced with a PEDOT/PSS film (hereinafter also abbreviated as
"PEDOT/PSS + CF film")
[0141] Table 4 shows materials used in each layer ofOPVs of Example B1 and Comparative
Example, Table 5 shows film production conditions for producing the films oflayers by spin
coating, and Fig. 5 illustrates the various sizes (unit: mm) of the produced solar cell (OPV).
The electricity generation region of the produced OPV was 4 x 25 mm (area of 1 cm2
), as
illustrated in Fig. 5. Heating in film production in each method other than a vapor
deposition method was performed on a hot plate.
A film production solution for the upper electrode (transparent electrode) ofOPV of
Comparative Example [carbon fiber-containing conductive polymer dispersed liquid] contains
no carbon fiber.
[0142] A substrate used in OPVs of Example Band Comparative Example was an insulating
smooth PCM (insulating smooth coated metal sheet) including a coated layer including one
clear coating film on one surface of a galvanized steel sheet. The substrate was the coated
metal substrate, in which a value of the arithmetic mean roughness Ra of a surface of the
coated layer was 12 nm, the minimum value of dynamic storage elastic modulus in the
rubber-like elastic region of a clear coated layer was I .2 x 107 Pa, the total film thickness of a
coating film layer was 15 ~un, and a leakage current value in application of a voltage of 100 V
was 55 x 10'7 A/cm2
•
[0143]
[Table 4]
Produced layer
Film production solution for upper
electrode (transparent electrode)
(Film production solution for
PEDOT/PSS + CF film)
Film production solution for hole
transpmt layer
(Film production solution for
PEDOT/PSS film)
Film production solution for
electricity-generating layer
(Film production solution for
PJHTIPCBM film)
Precursor solution for electron
transport layer
(Precursor solution for ZnO film)
Film production solution for
substrate electrode
(Film production solution for
PEDOT/PSS film)
Insulating smooth PCM for
[0144]
[Table 5]
substrate
Layer produced by spin coating
Substrate electrode
(PEDOT/PSS film)
Electron transport layer
(ZnO film)
Electricity-generating layer
(PJHT/PCBM film)
Hole transpmt layer
(PEDOT/:PSS film)
Abbreviation Component material
PEDOT/PSS
Poly(3,4-ethylenedioxythiophene )/polystyrene
sulfonate
TRITON TRITON-X!OO
DMSO Dimethylsulfoxide
CF Carbon fiber
PEDOT/PSS
Poly(3,4-ethylenedioxythiophene )/polystyrene
sulfonate
TRITON TR!TON-X!OO
PJHT Poly(J-hexylthiophene-2,5-diyl)
PCBM [6,6]-Phenyl C6l butyric acid methyl ester
CB Chlorobenzene
Zn(acea)2 Zinc acetate
AA Acetylacetone
MEA Monoethanolamine
PEDOT Poly(3,4-ethylenedioxythiophene )/polystyrene
/PSS sulfonate
TRITON TRITON-XlOO
DMSO Dimethylsulfoxide
- Polyester-based coatit1g, melamine resin, etc.
GI Galvanized steel sheet
Rotational speed (rpm) Rotation time (sec)
300 60
2000 60
700 60
6000 60
[0145] Each OPV was produced as follows.
The insulating smooth PCM was cut to produce a substrate of 38 x 38 nun, the
substrate was washed with distilled water and 2-propanol, and the film production solution for
a substrate electrode (PEDOT/PSS dispersion liquid) was then applied to a coated surface by
a spin coater (expected film thickness of 1 11m after drying) to form a substrate electrode.
[0 146) Then, the following layers were produced on the substrate electrode by a spin coating
method, to produce an electricity generation unit.
·Electron transpott layer (ZnO film): The precursor solution for an electron transport
layer was stirred at 50°C for 30 minutes, and a film was then produced, and was heated at
1 00°C for 1 hour (dry film thickness of 60 11m).
·Electricity-generating layer (P3HT/PCBM film): The film production solution for an
electricity-generating layer was stirred at 50°C for 6 hours, a film was then produced, and was
subjected to natural drying for 30 minutes (dried film thickness of200 11m).
·Hole transpott layer (PEDOT/PSS film): The film production solution for a hole
transport layer was stirred at ordinary temperature for 6 hours, and a film was then produced
(without requiring (drying step) (dried film thickness of 110 11m).
[0147] Subsequently, a transparent electrode was formed using the film production solution
for an upper electrode (transparent electrode) (conductive polymer dispersed liquid containing
carbon fibers). Specifically, in the case ofOPV of Example B1, the same electrode as the
transparent electrode of the test number 43 of Example A was formed as an upper electrode on
the electricity generation unit (hole transport layer thereof) by a drop-casting method. In the
case of OPV of Comparative Example, a carbon single layer electrode including a carbon film
was formed as an upper electrode on the electricity generation unit (hole transport layer
thereof) by a vacuum deposition method.
[0 148) Each produced OPV was connected in series with an I-V measurement apparatus
(W32-6244SOL3X manufactured by SYSTEMHOUSE SUNRISE CORP.), and was swept at
voltages ranging from -1.0 V to 1.0 V, and a current value was measured. A solar simulator
(XES-155SI manufactured by SAN-EI ELECTRIC CO., LTD.) was used as a light source,
and pseudo-sunlight ofAM1.5G-100 mW/cm2 was used. Irradiation of simulated sunlight
was performed from an upper electrode side, and an I-V curve was obtained.
[0149) A schematic view of the I-V curve is illustrated in Fig. 6. The I-V curve provides
the following parameters.
0
·Short-circuit photocurrent density Jsc: Photocurrent density (A/cm2
) at a voltage of
·Open-circuit photovoltage Voc: Photovoltage (V) at s current ofO
·Fill factor FF: P/(Jsc x Voc)
·Power conversion efficiency PCE (%)=PIE x I 00 (in which Pis the maximum
electrical output (W/cm2
) ofOPV, and E is the incident light power)
[0 !50] The parameters of the produced OPV s are shown in Table 6.
[0 151]
[Table 6]
Example Bl Comparative Example
Upper electrode PEDOT/PSS + CF film Carbon film (C film)
Hole transpmt layer PEDOT/PSS film PEDOT/PSS film
Electricity-generating
P3HT/PCBM film P3HT/PCBM film
layer
Layer
configuration
Electron transport
layer
ZnO film ZnO film
Substrate electrode PEDOT/PSS film PEDOT/PSS film
Substrate
Insulating smooth PCM Insulating smooth PCM
(One-coat clear Gl) (One-coat clear Gl)
Jsc (mAcn,-2
) 0.27 0.04
Evaluation Voc (V) 0.03 O.G7
results FF 0.25 0.26
PCE(%) 0.002 0.0008
[0152] It is clear from the above that the fill factor FF and power conversion efficiency PCE
of the OPV of Example Blare improved in comparison with those of the OPV of
Comparative Example.
As a result, it is clear that the electricity generation ability of the OPV is improved by
the transparent electrode of Example.
[0153] The embodiment and Examples which are examples of the invention were described
above. However, the embodiment and Examples described above merely exemplifY the
invention. Accordingly, the invention is not limited to the embodiment and Examples
described above, and changes of the embodiment and Examples described above can be made
without departing from the gist of the invention, if appropriate.
[0154] The entire disclosures of Japanese Patent Application No. 2014-078063 and Japanese
Patent Application No. 2014-208285 are incorporated herein by reference.
All documents, patent applications, and technical standards described in this
specification are herein incorporated by reference to the same extent as if each individual
document, patent application, or technical standard was specifically and individually indicated
to be incorporated by reference.
Jr7 3 {

CLAIMS
1. A transparent electrode, comprising:
a conductive polymer layer; and
a plurality of carbon fibers having a diameter larger than a thickness of the
conductive polymer layer,
wherein the carbon fibers are partially embedded in the conductive polymer layer.
2. The transparent electrode according to claim 1, wherein the diameter of the carbon
fibers is from 2 to 90 times the thickness of the conductive polymer layer.
3. The transparent electrode according to claim 1 or claim 2, wherein the diameter of
the carbon fibers is from 2 to 15 fHTI, and the thickness of the conductive polymer layer is
from 5 to 650 nm.
4. The transparent electrode according to any one of claim I to claim 3, wherein lengths
of the carbon fibers are from 50 to 7000 j.lm.
5. The transparent electrode according to any one of claim 1 to claim 4, wherein an area
rate of the carbon fibers, in a case of being viewed liom a direction perpendicular to a plane
of the transparent electrode, is from 40 to 90% with respect to the transparent electrode.
6. An organic electronic device, comprising:
a substrate;
a substrate electrode that is arranged on the substrate;
an organic functional layer that is arranged on the substrate electrode; and
the transparent electrode according to any one of claim 1 to claim 5, the transparent
electrode being arranged on the organic functional layer.
7. The organic electronic device according to claim 6, wherein the substrate is a coated
metal substrate or a plastic substrate.
8. The organic electronic device according to claim 6 or claim 7, wherein the organic
fi.mctionallayer is an organic fimctionallayer comprising an electricity-generating layer as a
photoelectric conversion layer.
9. The organic electronic device according to any one of claim 6, to claim 8, further
comprising a sealing layer that seals the substrate electrode, the organ,ic functional layer, and
the transparent electrode.