DESCRIPTION
NONWOVEN FABRIC LAMINATE
TECHNICAL FIELD
[OOOl]
The present invention relates to a nonwoven fabric
laminate that is capable of being disinfection-treated with
10 electron beam and is excellent in water resistance,
low-temperature sealability and softness.
BACKGROUND ART
[0002]
15 Polyethylene nonwoven fabrics, as compared with
polypropylenenonwovenfabrics, are softerandprovide superior
texture, and are excellent in heat-sealability and have a less
degree of deterioration even after irradiated with electron
beamor radiation, andthereforeare suitable formedical gowns,
20 absorbent articles andpackaging/supporting/backingmaterials
for various articles.
[0003]
However, in general, polyethylene is inferior to
polypropylene in melt spinnability, and thus polyethylene
nonwoven f a b r i c s obtainedbyspunbondingmethodormelt-blowing
method hardly have f i n e f i b e r s and have i n f e r i o r t e x t u r e , and
t h e r e f o r e use thereof is extremely l i m i t e d . An exemplary
attempt t o reduce t h e f i b e r diameter of polyethylene f i b e r is
5 i n c r e a s i n g t h e spinning temperature: i n t h i s case, p a r t of
polyethylene could be c r o s s l i n k e d t o cause g e l a t i o n , and thus
molding s t a b i l i t y is not e x c e l l e n t .
[0004]
I n o r d e r t o a d d r e s s suchaproblem, therehasbeenproposed
10 a method i n which polyethylene f i b e r s , and f i b e r s such as a
I
I p o l y e s t e r having a highmelting point a r e spun i n p a r a l l e l from
the same s p i n n e r e t , t o obtain f i n e polyethylene f i b e r s (Patent
L i t e r a t u r e 1: JP-A-2003-506582). However, t h i s method
r e q u i r e s complicated molding apparatus, such as the placement
15 of molding machines f o r polyethylene and p o l y e s t e r with
c o n t r o l l e d conditions, and t h e r e f ore may be i n f e r i o r i n
continuous production with s t a b i l i t y . In the nonwoven
conjugate sheet m a t e r i a l obtained by t h i s method, f i b e r s
forming the melt-blown nonwoven f a b r i c l a y e r a r e . so-called
20 side-by-side conjugate f i b e r s preparedbybondingpolyethylene
a n d p o l y e s t e r , w h e r e i n o n t h e s u r f a c e ofthemelt-blownnonwoven
f a b r i c l a y e r , t h e p o l y e s t e r p a r t o f t h e conjugate f i b e r s a p p e a r .
Thus, a laminate of such conjugate f i b e r s with a spunbonded
nonwoven f a b r i c is poorly embossed and may be i n f e r i o r i n fuzz
I r e s i s t a n c e a f t e r i r r a d i a t e d with e l e c t r o n beam.
[0005]
Furthermore, i n order t o provide a melt-blown
polyethylene nonwoven f a b r i c having an average f i b e r diameter
5 of not more than 5 pm, t h e r e has been proposed a method which
employs a r e s i n composition containing a polyethylene having
aweight averagemolecular weight of 21,000to 45,000 a n d a m e l t
flow r a t e of 15 t o 250 g/10 min, and a polyethylene wax having
a weight average molecular weight of 6,000 t o 12,000, a t weight
10 r a t i o ranging from 70/30 t o 30/70 (Patent L i t e r a t u r e 2:
JP-B-3995885). However, t h e melt-blown polyethylene nonwoven
f a b r i c obtainedby such amethodmayhaveinsufficient s t r e n g t h
when used as a s i n g l e l a y e r f o r medical gowns, absorbent
a r t i c l e s and packaging/supporting/backing m a t e r i a l s f o r
I 15 various a r t i c l e s .
[0006]
In Patent L i t e r a t u r e 2, i n order t o allow a melt-blown
polyethylene nonwoven f a b r i c t o have improved abrasion
r e s i s t a n c e a n d fuzz r e s i s t a n c e , therehasbeenproposedamethod
20 which laminates a melt-blown polyethylene nonwoven f a b r i c and
a spunbonded nonwoven f a b r i c . S p e c i f i c a l l y , t h e r e has been
proposed a method of laminating a melt-blown polyethylene
nonwoven f a b r i c , w i t h a p o l y e t h y l e n e spunbondednonwovenfabric
or with a spunbonded nonwoven f a b r i c formed from a conjugate
f i b e r of polyethylene and polypropylene. However, t h e
nonwoven f a b r i c laminate o b t a i n e d b y laminatingthemelt-blown
polyethylene nonwoven f a b r i c and t h e polyethylene spunbonded
nonwoven f a b r i c , although s t a b l e with r e s p e c t t o e l e c t r o n beam
5 o r gamma ray, mayhave i n s u f f i c i e n t s t r e n g t h . O n t h e o t h e r h a n d ,
t h e nonwoven f a b r i c l a m i n a t e o b t a i n e d by laminating t h e
melt-blown polyethylene nonwoven f a b r i c and t h e spunbonded
nonwoven f a b r i c formed fr'omthe conjugate f i b e r of polyethylene
andpolypropylene, althoughhaving g o o d b a r r i e r p r o p e r t i e s and
10 s t r e n g t h , may be d e t e r i o r a t e d , be degenerated o r r e l e a s e odor
and t h e l i k e by e l e c t r o n beam o r gamma ray applied upon
sterilization/disinfection.
C i t a t i o n L i s t
P a t e n t L i t e r a t u r e
[Patent L i t e r a t u r e 1 1 JP-A-2003-506582
[Patent L i t e r a t u r e 21 JP-B-3995885
SLMtTARY OF THE INVENTION
TECHNICAL PROBLEM
[0008]
It is an o b j e c t of t h e p r e s e n t i n v e n t i o n t o provide a
nonwoven f a b r i c laminate t h a t is capable of being
disinfection-treatedwith e - g . , electronbeamand is e x c e l l e n t
i n t e n s i l e s t r e n g t h , b a r r i e r p r o p e r t i e s , low-temperature
scalability, abrasion r e s i s t a n c e (fuzz r e s i s t a n c e ) and
s o f t n e s s .
TECHNICAL SOLUTION
[0009]
Thepresent inventionprovides anonwovenfabriclaminate
obtainedby laminating a spunbondednonwoven f a b r i c on a t l e a s t
10 one surface of amelt-blownnonwoven f a b r i c ( A ) , themelt-blown
nonwoven f a b r i c (A) comprising f i b e r s of an ethylene-based
polymer r e s i n composition of an ethylene-based polymer ( a ) and
an ethylene-based polymer wax ( b ) , the spunbonded nonwoven
f a b r i c comprising a conjugate f i b e r formed from a p o l y e s t e r ( x )
15 and an ethylene-based polymer (y) such t h a t a t l e a s t p a r t of
the f i b e r surface is the ethylene-based polymer ( y ) .
ADVANTAGEOUS EFFECTS OF THE INVENTION
[OOlO]
The nonwoven f a b r i c laminate of the p r e s e n t i n v e n t i o n is
capable of being disinfection/sterilization-treated with
electronbeamor gamma ray a n d i s e x c e l l e n t i n s o f t n e s s , b a r r i e r
p r o p e r t i e s ( b a r r i e r p r o p e r t i e s o f p r e v e n t i n g t h e permeation of
anaqueous s o l u t i o n suchas water, bloodor b a c t e r i a containing
water; water impermeability), abrasion resistance, tensile
strength and low-temperature sealability.
DESCRIPTION OF EMBODIMENTS
5 [OOll]

The ethylene-based polymer (a), which is one component
of the ethylene-based polymer composition forming the
melt-blownnonwovenfabric (A) constitutingthenonwovenfabric
10 laminate of the present invention, is an ethylene homopolymer
or a copolymer of ethylene and other a-olefins wherein the
ethylene-based polymer (a) is a polymer that contains ethylene
as a main component and usually has a density of 0.870 to 0.980
g/cm3, preferably 0.900 to 0.980 g/cm3, more preferably 0.920
15 to 0.975 g/cm3, particularly preferably 0.940 to 0.970 g/cm3.
[0012]
The ethylene-based polymer (a) according to the present
invention is usually a crystalline resin manufactured and
marketed under the name of e.g., high-pressure low-density
20 polyethylene, linear low-density polyethylene (so-called
LLDPE), middle-density polyethylene, or high-density
polyethylene.
[0013]
Examples of other a-olefins to be copolymerized with
! ethylene include a-olefins having 3 to 20 carbon atoms such as
propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene,
1-octadecene and 1-eicosene. These ethylene-based polymers
5 may be of a single kind, or a mixture of two or more kinds.
[0014]
If an ethylene-based polymer with a density below the
~ above range is used, the obtainable melt-blown nonwoven fabric
I
may be inferior in durability, heat resistance, strength, and
10 stability after the passage of time. On the other hand, if an
ethylene-basedpolymerwithadensityexceedingthe above range
is used, the obtainable melt-blown nonwoven fabric tends to be
inferior in heat-sealability and softness.
[0015]
15 In the present invention, the density of the
ethylene-basedpolymer (a) is avalue obtainedbyheattreating
at 120°C for 1 hour a strand obtained in melt flow rate (MFR)
measurementperformedat190"Cunder aloadof 2.16 kg, andthen
gradually cooling the treated strand over a period of 1 hour
20 to room temperature, and thereafter subjecting the cooled
strand to the measurement using a density gradient tube.
[0016]
The MFR of the ethylene-based polymer (a) according to
the present invention is not particularly limited, as long as
the ethylene-based polymer (a) is capable of being mixed with
a later-described ethylene-based polymer wax (b) to produce a
melt-blown nonwoven fabric, but the ethylene-based polymer (a)
usually has MFR (measured in accordance with ASTM Dl238 under
5 a load of 2.16 kg at 190°C) of 10 to 250 g/10 min, preferably
-20 to 200 g/10 min, more preferably of 50 to 150 g/10 min, in
terms of the fineness of the obtainable fiber diameter and
spinnability.
10 The ethylene-based polymer (a) according to the present
invention may be a polymer obtainable by various known
production methods, for example a high-pressure method, or a
I
I middle/low-pressure method using a Ziegler catalyst or a
I
I
I metallocene catalyst. It is particularly preferred to use an
1 15 ethylene-basedpolymer obtainable by the polymerization using
a metallocene-based catalyst, because of further reducing the
fiber diameter of the obtainable fiber.
[0018]

20 The ethylene-based polymer wax (b), which is one
componentoftheethylene-basedpolymercomposition formingthe
melt-blownnonwovenfabric (A) constitutingthenonwovenfabric
laminate of the present invention, is a polymer that is usually
produced and marketed as a polyethylene wax and has a lower
molecular weight than that of the ethylene-based polymer (a),
i.e., a wax polymer.
[0019]
The ethylene-based polymer wax (b) according to the
5 present invention is an ethylene homopolymer or a copolymer of
ethylene and an a-olefin having 3 to 20 carbon atoms; more
preferably an ethylene homopolymer. When the ethylene
homopolymer is used, kneadability with the ethylene-based
polymer (a) is excellent, and spinnability is also excellent.
10 The ethylene-based polymer wax may be of a single kind or a
mixture of two or more kinds. -
.[0020]
The ethylene-based polymer wax (b) according to the
present invention preferably has a softening point as measured
15 in accordance with JIS K2207 of 110 to 145°C. In terms of
spinnability and kneadability with the ethylene-based polymer
(a) and also in terms of the fiber diameter of the obtainable
fiber, the weight average molecular weight (Mw) of the
ethylene-based polymer wax (b) is usually within the range of
20 6,000 to 15,000, preferably 6,000 to 10,000. If an
ethylene-based polymer wax with Mw exceeding the above range
is used, the obtainablemelt-blownnonwoven fabricmay not have
sufficiently-fine fibers.
[0021]
Theweight averagemolecular weight ofthe ethylene-based
polymerwax (b) accordingtothepresent inventionis determined
based on GPC measurement, and is a value measured under the
following conditions. Theweight averagemolecular weight was
determined by preparing a calibration curve using a
commercially available monodispersed standard polystyrene and
employing the following conversion method.
[0022]
Apparatus: gel permeation chromatograph, Alliance GPC2OOO
(manufactured by Waters)
Solvent: o-dichlorobenzene
Column: TSKgel column (manufactured by Tosoh) x 4
Flow rate: 1.0 ml/min
Specimen: 0.15 mg/mLo-dichlorobenzene solution
Temperature: 140°C
Molecular weight conversion: PE conversion/general
calibration method
For the calculation of the general calibration,
coefficients of Mark-Houwink viscosity equations were used.
[0023]
Coefficient of polystyrene (PS) : KPS = 1.38 x aPS = 0.70
Coefficient of polyethylene (PE) : KPE = 5.06 x aPE = 0.70
[0024]
The ethylene-based polymer wax (b) according to the
present invention has a density as measured in accordance with
JIS K6760, which is not particularly limited, usually of 0.890
to 0.980 g/cm3, preferably 0.910 to 0.980 g/cm3, more preferably
0.920 to 0.980 g/cm3, particularly preferably 0.940 to 0.980
5 g/cm3. By using the ethylene-based polymer wax (b) having such
a density range, kneadability with the ethylene-based polymer
(a) is excellent, and spinnability, and stability after the
passage of time are also excellent.
[0025]
10 The ethylene-based polymer wax (b) according to the
present invention may be produced by a commonly-used method
which is not particularly limited, such as production method
of low molecular weight polymer polymerization, or method of
thermally degrading a high molecular weight ethylene-based
15 polymer to reduce its molecular weight. As is the case with
the ethylene-based polymer (a), it is preferred to use an
ethylene-based polymer wax obtainable by using a
metallocene-based catalyst, because of further reducing the
fiber diameter of the obtainable fiber.
20 [0026]
Themetallocene catalyst is notparticularlylimited, and
examples thereof are those described in JP-A-2007-246832.
Examples of preferred metallocene-based catalysts are olefin
polymerization catalysts comprising:
(E) ametallocene compoundof atransitionmetal selected
from Group 4 of the periodic table, and
(F) at least one kind of compound selected from (f-1)
organicaluminum-oxycompounds, (f-2) compoundsthat reactwith
5 the bridged metallocene compound (A) to form an ion pair and
(f-3) organoaluminum compounds.
[0027]

The ethylene-based polymer composition, which forms the
10 melt-blown nonwoven fabric (A) according to the present
invention, is a composition containing the ethylene-based
polymer (a) and the ethylene-based polymer wax (b) . The
ethylene-based polymer composition according to the present
invention, by containing the ethylene-based polymer wax (b),
15 allows the obtainable melt-blown nonwoven fabric to have a
reduced average fiber diameter. If the amount of the
ethylene-based polymer wax (b) is small, the average fiber
diameter may not be reduced. On the other hand, if the amount
oftheethylene-basedpolymerwax (b) is too large, the spinning
20 maybe difficult, andthe obtainable fibertendstohave reduced
strength. In view of this, the ratio of the ethylene-based
polymer (a) to the ethylene-based polymer wax (b), (a) / (b)
weight ratio, is preferably in the range of 20/80 to 80/20,
[0028]
The ethylene-based polymer composition according to the
present invention usually has a half-crystallization time of
85 sec or more, preferably 87 sec or more, more preferably 92
i 5 sec or more, still more preferably 97 sec or more, most
preferably 102 sec or more. The upper limit of the
half-crystallization time is not particularly limited.
In the present invention, the half-crystallization time
10 was measured by the following method. Using a differential
scanning calorimeter measurement apparatus (DSC7 manufactured
by PerkinElmer Co., Ltd.), the specimen, set in an amount of
about 5 mg, was allowed to stand at 200 "C for 5 min and thereby
was completely molten. Thereafter, the molten specimen was
15 rapidly cooled to 115°C at a temperature cooling rate of
32O0C/min to perform isothermal crystallization. The time
taken from the start of cooling until the crystallization heat
reached half of the total heating value was defined as
half-crystallization time.
The ethylene-based polymer composition with the
half-crystallization time satisfying the above range is
obtained by using a metallocene-catalyzed polymer as. at least
one of the ethylene-based polymer (a) and ethylene-based
polymer wax (b) that form the ethylene-based polymer
composition, although depending on the weight ratio of the
ethylene-based polymer (a) to the ethylene-based polymer wax
(b) in the ethylene-based polymer composition, and the
5 molecular weight of the ethylene-based polymer wax (b) . It is
more preferable that the ethylene-based polymer wax (b) is a
metallocene-catalyzed polymer in terms of obtaining an
ethylene-based polymer composition with the
half-crystallization time satisfying the above range.
For the production of the ethylene-based polymer
composition according to the present invention, it is possible
to suitably use known catalysts such as magnesium-supported
titanium catalysts described in e-g., JP-A-S57(1982)-63310,
JP-A-H4(1992)-218508, JP-A-2003-105022, or metallocene
catalysts described in e.g., W001/53369, W001/27124,
The ethylene-based polymer composition according to the
present invention preferably comprises a transition metal
compound. The composition comprising a transition metal
compound is obtained by using a metallocene-catalyzed polymer
as at least one of the ethylene-based polymer (a) and the
ethylene-based polymer wax (b) that form the ethylene-based
polymer composition. Thus, as a transition metal compound,
zirconium, titanium, hafnium compounds and the like contained
in metallocene catalysts can be mentioned.
5 COO331
The total content of transition metals contained in the
transition metal compound in the ethylene-based polymer
composition is usually not more than 2 ppm, preferably not more
than 1 ppm, more preferably not more than 0.5 ppm, most
10 preferably not more than 0.3 ppm. The total content of
transition metals is calculated by collecting a specimen in a
fluororesin-made container, adding an ultra-high-purity
nitricacidthereto, andthenmicrowave-decomposingthemixture,
followed by ICP mass analysis method (ICP-MS method).
15 [0034]
The ethylene-based polymer composition according to the
present invention may optionally contain other polymers and
compounding agents such as coloring agents, stabilizers and
nucleating agents, in a range that does not impair the object
20 of the present invention. Examples of the optional components
are known ones including various stabilizers such as heat
stabilizers and weathering stabilizers, antistatic agents,
hydrophilizing agents, water-repellents, nucleating agents,
slip agents, antiblocking agents, anti-fogging agents,
l u b r i c a t i n g agents, dyes, pigments, n a t u r a l o i l and s y n t h e t i c
o i l .
Examples of t h e s t a b i l i z e r s include:
5 anti-aging agents such
2,6-di-t-butyl-4-methyl-phenol (BHT);
phenol-based a n t i o x i d a n t s such as
10 acid a l k y l e s t e r s ,
p i o n a t e ] , Irganox 1010 (product name; hindered phenol-based
a n t i o x i d a n t ) ;
f a t t y acid metal s a l t s such as zinc s t e a r a t e , calcium
~ 15 s t e a r a t e , calcium 1,2-hydroxystearate;
I polyhydric alcohol f a t t y acid esters such as g l y c e r o l
I monostearate, g l y c e r o l d i s t e a r a t e , p e n t a e r y t h r i t o l
1 monostearate, pentaerythritoldistearate, a n d p e n t a e r y t h r i t o l
I
t r i s t e a r a t e .
20 These may be used i n combination.
[0036]
Fillersmaybeincorporated, s u c h a s s i l i c a , diatomaceous
e a r t h , alumina, titaniumoxide, magnesiurnoxide, pumicepowder,
pumice balloon, aluminumhydroxide, magnesiumhydroxide, b a s i c
SF-2486
I
magnesium carbonate, dolomite, calcium sulfate, potassium
titanate, barium sulfate, calcium sulphite, talc, clay, mica,
asbestos, calcium silicate, montmorillonite, bentonite,
graphite, aluminum powders and molybdenum sulfide.
5 [0037]
The ethylene-based polymer composition according to the
present invention is obtained by mixing the ethylene-based
polymer (a), the ethylene-based polymer wax (b), and these
optional components by various known methods.
10 [0038]

The melt-blown nonwoven fabric (A) constituting the
nonwoven fabric laminate of the present invention is a
melt-blown nonwoven fabric obtained from the ethylene-based
15 polymer composition. The fibers forming the melt-blown
nonwoven fabric usually have an average fiber diameter of not
morethanlOIJm. Inordertoobtainamelt-blownnonwovenfabric
having low basis weight and much superior barrier properties,
it is desirable that the fibers formingthemelt-blown nonwoven
20 fabric have an average fiber diameter of 0.5 to 8 ym, more
preferably 1 to 5 pm, still more preferably 1 to 4 ym,
particularly preferably 2 to 4 ym.
[0039]
Whenthe average fiber diameter is withinthe above range,
I the obtainable melt-blown nonwoven fabric has good evenness,
and the resultant nonwoven fabric is excellent in barrier
properties.
5 The melt-blown nonwoven fabric (A) according to the
present invention usually has a basis weight of not less than
0.5 g/m2, preferably 10 to 50 g/m2, more preferably 15 to 45
g/m2, still more preferably 20 to 40 g/m2. If the basis weight
I
I is too low, the resulting nonwoven fabric laminate may have
i 10 lowerwaterpressureresistanceandinferiorbarrierproperties.
I Theupper limit ofthebasis weight is notparticularlylimited,
1 but if the basis weight is too high, the resulting nonwoven
1 fabric laminate tends to have inferior softness. On the other
1 hand, in the use that does not require such high barrier I
I 15 properties but requires softness, heat-sealability and
lightness, such as the use in e.g., sanitary materials, the
basis weight is 0.5 to 5 g/m2, more preferably 0.5 to 3 g/m2.
[0041]

20 The melt-blown nonwoven fabric (A) according to the
present invention may be produced using the ethylene-based
polymer composition by known melt-blown nonwoven fabric
production method. Specifically, for example, a melt-blowing
I method can be performed such that the ethylene-based polymer
I composition is m e l t kneaded with a n e x t r u d e r o r t h e l i k e , and
t h e molten substance is discharged from a s p i n n e r e t having
spinning n o z z l e s , and blown by a high-speed/high temperature
a i r f l o w i n j e c t e d from t h e periphery of t h e s p i n n e r e t , t o be
5 deposited on a c o l l e c t i n g b e l t a s s e l f - a d h e s i v e m i c r o f i b e r s i n
a s p e c i f i c t h i c k n e s s t o t h e r e b y produce aweb. This methodmay
be subsequently followed by e n t a n g l i n g treatment a s needed.
[0042]
As a method of e n t a n g l i n g t h e deposited web, various
10 methods c a n b e u s e d a p p r o p r i a t e l y , s u c h a s heatembossingusing
an emboss r o l l , fusion bonding using u l t r a s o n i c wave, f i b e r
entanglingmethodusing a water jet, f u s i o n b o n d i n g u s i n g a hot
a i r through, a method u s i n g n e e d l e punching. In o b t a i n i n g t h e
nonwoven f a b r i c l a m i n a t e o f t h e present invention, heat
15 embossingispreferableinterms o f t h e s i m p l i c i t y o f l a m i n a t i n g
procedure.
[0043]

Thepolyester ( x ) , w h i c h i s onecomponent o f t h e c o n j u g a t e
20 f i b e r forming t h e spunbonded nonwoven f a b r i c c o n s t i t u t i n g t h e
nonwoven f a b r i c laminate of t h e present invention, is a known
p o l y e s t e r u s e d a s a r a w m a t e r i a l f o r spunbondednonwovenfabrics,
and s p e c i f i c examples t h e r e o f i n c l u d e polyethylene
t e r e p h t h a l a t e , polybutylene t e r e p h t h a l a t e , polytrimethylene
terephthalate, and copolymers and terpolymers thereof.
[0044]
The molecular weight of the polyester (x) according to
the present invention is not particularly limited as long as
5 the polyester (x) is capable of being conjugated with a
later-described ethylene-based polymer (y) to produce a
spunbonded nonwoven fabric. Of polyesters commercially
available or industrially available, those commercially
available for fiber use areparticularlydesired: specifically,
10 those having an intrinsic viscosity of 0.50 to 1.20 are
preferable.
[0045]

The ethylene-based polymer (y), which is one component
15 of the conjugate fiber forming the spunbonded nonwoven fabric
constituting the nonwoven fabric laminate of the present
invention, is a resin similar tothe ethylene-basedpolymer (a),
and is an ethylene homopolymer or a copolymer of ethylene and
other a-olefins wherein the ethylene-based polymer (y) is a
20 polymer that contains ethylene as a main component and usually
has a density of 0.870 to 0.990 g/cm3, preferably 0.900 to 0.980
g/cm3, more preferably 0.910 to 0.980 g/cm3.
[0046]
The ethylene-based polymer (y) according to the present
invention is usually a crystalline resin manufactured and
marketed under the name of e.g., high-pressure low-density
polyethylene, linear low-density polyethylene (so-called
LLDPE), middle-density polyethylene, or high-density
5 polyethylene.
[0047]
Examples of other a-olefins to be copolymerized with
ethylene include a-olefins having 3 to 20 carbon atoms such as
propylene, 1-butene, 1-pentene, 1-hexene, 4-methyl-1-pentene,
10 1-octene, 1-decene, 1-dodecene, 1-tetradecene, 1-hexadecene,
1-octadecene and 1-eicosene. These ethylene-based polymers
may be of a single kind, or a mixture of two or more kinds.
[0048]
The MFR of the ethylene-based polymer (y) according to
15 the present invention is not particularly limited as long as
the ethylene-based polymer (y) is capable of being conjugated
withthepolyester (x) toproduce the spunbondednonwovenfabric,
but the ethylene-based polymer (y) usually has MFR (measured
in accordance with ASTM Dl238 under a load of 2.16 kg at 190 " C )
20 of 0.5 to 60 g/10 min, preferably 10 to 60 9/10 min, in terms
of spinnability.
[0049]
The ethylene-based polymer (y) according to the present
inventionmaybe apolymer obtainedbyvarious knownproduction
methods, such as high pressure method, and middle/low pressure
method using a Ziegler catalyst or a metallocene catalyst, as
is the case with the ethylene-based polymer (a).
[0050]
5 The ethylene-based polymer (y) according to the present
invention may contain 0.1 to 0.5% by weight of a slip agent
composed of a fatty acid amide such as oleic amide, erucamide
and stearic amide. When the ethylene-based polymer (y)
contains a slipagent, the resulting spunbondednonwoven fabric
10 has much improved fuzz resistance.
[0051]
The polyester (x) and/or the ethylene-based polymer (y)
according to the present invention may contain other polymers,
coloring agents, various stabilizers such as heat stabilizers
15 and weathering stabilizers, antistatic agents, hydrophilizing
agents, water-repellents, nucleating agents, slip agents,
antiblocking agents, anti-fogging agents, lubricating agents,
dyes, pigments, natural oil and synthetic oil, in a range that
does not impair the object of the present invention.
20 [0052]
In the spunbonded nonwoven fabric according to the
present invention, the conjugate fiber forming the spunbonded
I I nonwoven fabric is a conjugate fiber formed from the polyester
of the f i b e r s u r f a c e is t h e ethylene-based polymer ( y ) .
[0053]
As long as t h e ethylene-based polymer (y) is exposed on
5 p a r t of t h e s u r f a c e of t h e conjugate f i b e r , t h e shape of t h e
conjugate f i b e r is not p a r t i c u l a r l y l i m i t e d . By t h e
ethylene-basedpolymer (y) being exposedonpart o f t h e surface
of the conjugate f i b e r , t h e adhesion with t h e melt-blown
nonwoven f a b r i c (A) is e x c e l l e n t .
10 [0054]
O f t h e s e c o n j u g a t e f i b e r s , p r e f e r r e d a r e conjugate f i b e r s
having a cross s e c t i o n with a weight r a t i o of t h e p o l y e s t e r ( x )
t o the ethylene-based polymer (y) , [ (x) / (y) I , being i n the range
of 5/95 t o 95/5, p a r t i c u l a r l y p r e f e r a b l y 20/80 t o 80/20. It
15 is p r e f e r a b l e t h a t t h e r a t i o o f t h e polyester-basedpolymer (x)
t o the ethylene-based polymer (y) is within t h i s range, because
t h e r e s u l t i n g spunbonded nonwoven f a b r i c is e x c e l l e n t i n t h e
balance between s t r e n g t h and s o f t n e s s .
100551
20 As the conjugate f i b e r according t o t h e present invention,
1 p r e f e r r e d is a c o n c e n t r i c or e c c e n t r i c core-sheath type
I conjugate f i b e r composed of a core formed I from t h e
polyest.er-based polymer (x) and a sheath formed from t h e
ethylene-based polymer (y) , or a side-by-side type conjugate
fiber formed from the polyester-based polymer (x) and the
ethylene-based polymer (y) .
[0056]
The conjugate fiber according to the present invention
5 usually has an average fiber diameter of 5 to 30 pm (about 0.2
to 7 denier), preferably 10 to 20 pm.
[0057]

The spunbondednonwoven fabric constitutingthe nonwoven
10 fabric laminate of the present invention is a nonwoven fabric
comprising a conjugate fiber formed from the polyester (x) and
the ethylene-based polymer (y) such that at least part of the
fiber surface is the ethylene-based polymer (y).
[0058]
15 The spunbonded nonwoven fabric according to the present
invention usually has a basis weight of 5 to 50 g/m2, preferably
10 to 25 g/m2.
[0059]

20 The spunbonded nonwoven fabric according tu the present
invention may be produced by known spunbonded nonwoven fabric
production method. Specifically, for example, a conjugate
melt-spinning method can be performed such that the polyester
(x) and the ethylene-based copolymer (y) are each molten in a
I desired range with a separate extruder or the like; and each
molten substance is discharged froma spinnerethaving spinning
I nozzles that is designed to form and discharge a desired
conjugate structure, to be spun into conjugate long fiber
5 filaments. Then, the filaments thus spun are cooled with a
cooling fluid, and given tension by drawing air to allow the
filaments to have a desired fineness. Thereafter, the spun
filaments are collected and deposited in a specific thickness
on a collecting belt. Then, the filaments are subjected to
10 entangling treatment. This method provides a spunbonded
nonwoven fabric. As a method of entangling treatment, the
methods adopted with regard to the melt-blown nonwoven fabric
can be mentioned. Of them, heat embossing is preferable. In
performing heat embossing, usually, the embossed area
15 percentage, which is appropriately determined, is preferably
5 to 30%.
[0060]

The nonwoven fabric laminate of the present invention is
20 formedbylaminatingthe spunbondednonwoven fabric comprising
the above conjugate fiber on at least one surface of the
melt-blown nonwoven fabric (A).
[0061]
The nonwoven fabric laminate of the present invention,
wherein on the melt-blown nonwoven fabric (A), the spunbonded
nonwoven fabric comprising the conjugate fiber is laminated,
is excellent in softness, barrier properties (high water
pressure resistance), strength, durability, evenness,
5 cloth-like appearance and texture.
[0062]
The structure of the nonwoven fabric laminate of the
present invention is not particularly limited, as long as at
least one surface layer thereof is a layer formed from the
10 spunbonded nonwoven fabric, but preferred is a layer structure
consisting of the spunbonded nonwoven fabric layer/the
melt-blown nonwoven fabric (A) layer, and a layer structure
consisting of the spunbonded nonwoven fabric layer/the
I ~ melt-blown nonwoven fabric (A) layer/the spunbonded nonwoven
15 fabric layer.
[0063]
The basis weight of the nonwoven fabric laminate of the
present invention, which can be appropriately determined
depending on use, required quality, economy and the like of the
20 nonwoven fabric laminate, is usually 6 to 150 g/m2, more
preferably 11 to 120 g/rn2, still more preferably 15 to 100 g/m2.
In the nonwoven fabric laminate ofthe present invention,
on at least one surface of the melt-blown nonwoven fabric (A),
the spunbonded nonwoven fabric comprising the conjugate fiber
is laminated, and both the nonwoven fabrics contain
ethylene-based polymers. Accordingly, when the melt-blown
nonwoven fabric (A) is bonded with the spunbonded nonwoven
5 fabric by heat embossing or the like, the bonding can be
performed easily, to provide a nonwoven fabric laminate having
an excellent interlayer adhesive strength.
The nonwoven fabric laminate of the present invention is
10 stable with respect to electron beam or gamma ray applied upon
The nonwoven fabric laminate of the present invention is
excellent in evenness as well as in breathability, barrier
15 properties and softness. In addition, the nonwoven fabric
laminate of the present invention, wherein one surface layer
or both surface layers are formed fromthe spunbonded nonwoven
fabric layer, is also excellent in strength, durability,
abrasion resistance and fuzz resistance.
20 [0067]
The nonwoven fabric laminate of the present invention
usually has a cantilever value as an index of softness of not
morethanlOOmm, preferablynotmorethan 90rnrn, morepreferably
not more than 80mm; andusuallyhas awaterpressure resistance
of not l e s s than 350 rnmAq, preferably not l e s s than 500 mmAq,
more preferably not less than 600 mrnAq.
[0068]
Thenonwoven f a b r i c laminate o f t h e present inventionmay
5 be s u b j e c t e d t o w a t e r r e p e l l e n t f i n i s h i n g a s needed. The water
r e p e l l e n t f i n i s h i n g can be performed by applying a water
r e p e l l e n t agent suchas a fluorine-basedwaterrepellentagent.
The appropriate deposition percentage of the water r e p e l l e n t
agent is 0.5 t o 5.0% by weight. An exemplary method f o r
10 imparting alcohol r e p e l l e n t p r o p e r t i e s is a method i n which a
fluorine-based f i n i s h i n g agent is deposited on the nonwoven
f a b r i c (b) a t a deposition percentage of 0.01 t o 3% by weight.
A t t h i s time, how t o deposit and dry t h e f i n i s h i n g agent are
not p a r t i c u l a r l y l i m i t e d . Examples .of the method f o r
15 depositing t h e f i n i s h i n g agent include spraying, soaking i n a
f i n i s h i n g agent bath followed by mangling, and coating.
Examples of the method f o r drying t h e f i n i s h i n g agent include
a method using a hot a i r d r i e r , a method using a t e n t e r , and
a method of contacting with a h e a t g e n e r a t o r .
20 [0069]
Thereby, the nonwoven f a b r i c laminate, f o r example when
used f o r medical gowns, prevents the permeation of water and
alcohol, enabling those who wear the laminate t o f e e l
comfortable.
Thenonwoven fabric laminate ofthe present inventionmay
be provided with antistatic properties. An exemplary method
of imparting antistatic properties is a method of applying an
5 appropriate antistaticproperty-irnpartingagent, suchas fatty
acid esters and quaternary ammonium salts. As the degree of
antistatic properties, in the J I S L1094C method under the
atmosphere of 20°C and 40% RH, not more than 1000 V is preferred
(a cotton cloth is used as a rubbing cloth). As the degree of
10 antistatic properties, in the J I S L1094C method under the
atmosphere of 20'C and 40% RH, not more than' 1000 V is preferred
(a cotton cloth is used as a rubbing cloth).
Thereby, the nonwoven fabric laminate, for example when
15 used for medical gowns, enables those who wear the laminate to
feel comfortable.
100721
With the nonwoven fabric laminate of the present
invention, short fiber/long fiber nonwoven fabrics of e-g.,
20 cotton, cupra, rayon, polyolefin-based fibers,
. polyamide-basedfibersorpolyester-basedfibersmaybefurther
laminated in a range that does not impair the object of the
present invention.
[0073]
The nonwoven fabric laminate of the present invention is
applicable to a whole range of sanitary materials, daily
commodities, industrial materials and medical materials. The
nonwoven fabric laminate of the present invention, because of
5 its excellence particularly in softness, breathability and
barrier properties, is suitably used for disposable diapers,
sanitary napkins, base cloth such as poultices, materials for
e.g., bed covers. In addition, the nonwoven fabric laminate
of the present invention, which is formed from the
10 polyethylene-basedfabrics andthe polyester-basedfabrics, is
stable with respect to electron beam or gamma ray applied upon
sterilization/disinfection, and thus can be suitably used
particularlyasmaterials of gowns, caps, masks anddrapesthat
are employed in hospitals and the like. Furthermore, the
15 nonwoven fabric laminate of the present invention, because of
its satisfactory after-processability such as
heat-scalability, can be applied to a whole range of daily
commoditiesincluding oxygen scavengers, portablebodywarmers,
heated poultice, masks, CD (compact disk) bags, food packaging
20 materials and clothing covers. For the same reason, the
nonwoven fabric laminate of the present invention is suitably
employable for automotive interiors and various backing
materials. The nonwoven fabric laminate of the present
invention, which is formed from fine fibers, is widely
applicable as liquid filter or air filter materials.

The production method of the nonwoven fabric laminate of
5 the present invention is not particularly limited as long as
being a method by which the melt-blown nonwoven fabric (A) and
the spunbonded nonwoven fabric are integrated to form a single
laminate.
[0075]
10 Specific employable examples without being limited
thereto include:
(i) a method in which on a previously-prepared
spunbonded nonwoven fabric, fibers obtained from the
ethylene-based polymer composition that are obtained by
15 melt-blowingmethodare directlydepositedto formamelt-blown
nonwoven fabric (A), and thereafter the spunbonded nonwoven
fabric and the melt-blown nonwoven fabric are fusion bonded to
eachotherbyheatembossingorthelike, to produce atwo-layer
laminate;
20 (ii) a method in which fibers obtained from the
ethylene-based polymer composition that are obtained by
melt-blowing method are directly deposited on a
previously-prepared spunbonded nonwoven fabric to form a
melt-blown nonwoven fabric (A), and further on the melt-blown
nonwoven fabric (A), a conjugate fiber formed by spunbonding
method is directly deposited to form a spunbonded nonwoven
fabric; and thereafter the spunbonded nonwoven fabric, the
melt-blown nonwoven fabric (A), and the spunbonded nonwoven
5 fabric are fusion bonded to one another, to produce a
three-layer laminate;
(iii) amethodinwhich a previously-prepared spunbonded
nonwoven fabric and a separately-producedmelt-blown nonwoven
fabric (A) are stacked on each other, and both the nonwoven
10 fabricsarethermocompressedtotherebybe fusionbondedtoeach
other, to produce a laminate; and
(iv) a method in which a previously-prepared spunbonded
nonwoven fabric and a separately-preparedmelt-blown nonwoven
fabric (A) are bonded by an adhesive such as a hot melt adhesive
15 or a solvent-based adhesive, to produce a laminate.
[0076]
To produce the nonwoven fabric laminate of the present
invention, the surfacewhere themelt-blownnonwoven fabric (A)
co;tacts with the spunbonded nonwoven fabric may be entirely
20 thermal fusion bonded or may be partly thermal fusion bonded.
It is preferred, however, that by heat embossing, the surface
where each nonwoven fabric layer contacts with one another is
partly thermal fusion bonded. At this time, the fusion-bonded
area (corresponding to the area embossed by an embossing roll)
is preferably 5 to 35% of the contacting area, more preferably
10 to 30% of the contacting area. When the fusion-bonded area
is within the above range, the nonwoven fabric laminate is
excellent in the balance between adhesive strength and
5 softness.
[0077]
In the method of bonding the spunbonded nonwoven fabric
and the melt-blown nonwoven fabric (A) by an adhesive, which
is an exemplary thermal fusion bonding method of the nonwoven
10 fabrics, examples ofthe hot melt adhesive include resin-based
adhesives such as vinyl acetate-based ones and polyvinyl
alcohol-based ones; and rubber-based adhesives such as
styrene/butadiene-basedones andstyrene/isoprene-basedones.
Examples of the solvent-based adhesive include organic solvent
15 adhesives and aqueous emulsion adhesives, e.g. solvent-based
rubber type adhesives such as styrene/butadiene-based ones,
styrene/isoprene-based ones and urethane-based ones;
solvent-based resin type adhesives such as vinyl acetate-based
ones and vinyl chloride-based ones. Of these adhesives,
20 rubber-basedhotmeltadhesives suchas styrene/isoprene-based
ones and styrene/butadiene-basedones are preferable, in terms
of their ability to allow for retaining the texture, the
properties of spunbonded nonwoven fabric.
EXAMPLES
Hereinafter, with reference t o Examples and Comparative
Examples o f t h e p r e s e n t invention, thepresent inventionismore
5 s p e c i f i c a l l y described. In the Examples and Comparative
Examples, measurement of respective properties of the
I melt-blown nonwoven fabric, the spunbondednonwoven fabric, or
I
I
the nonwoven fabric laminate was performed under the following
methods.
10 [0079]
(1) Average f i b e r diameter
A specimen was collected from the obtained nonwoven
f a b r i c , and was observed with a scanning electron microscope
a t a magnification of 1000, t o measure f i b e r diameters (pm) of
15 30 constituent f i b e r s , and an average f i b e r diameter thereof
was calculated.
[0080]
( 2 ) Basis weight
In accordance with JIS-L1096-1990, 6 . 4 . 2 , "mass per unit
20 areaunder standardconditions", t h e b a s i s weight wasmeasured.
From the obtained nonwoven fabric, c i r c u l a r t e s t pieces each
of 100 cm2 were collected. The t e s t pieces were collected a t
aplacethatwas arbitrarilydeterminedinthemachinedirection
(MD) and were collected a t 20 points with a uniform i n t e r v a l
I
that would form a straight line in the direction crossing the
machine direction (CD) . The test pieces were not collected at
a place between each end and 20 cm inward from each end of the
nonwoven fabric sample in the direction crossing the machine
5 direction (CD) . Using pan electronic balance (EB-330
manufactured by Shimadzu Corporation), a mass (g) of each test
piece collected was measured. Then, an average mass (g) of the
test pieces was calculated. The average mass calculated was
convertedtoamass (g) per1m2, whichwas roundedto onedecimal
10 place to provide a basis weight (g/m2) of each nonwoven fabric
sample.
[0081]
(3) Evaluation of tensile strength
From the nonwoven fabric laminate, a test piece of 25 mm
15 in width x 250 mm in length was collected, and was subjected
to tensile test in two directions: the machine direction (MD)
and the direction crossing the machine direction the
distance between chucks being 50 mm, the tensile rate being 100
mrn/min. Amaximurntensile loadwas defined as tensile strength
20 (N/25 mm). The measurement was performed five times and an
average value ofthe values obtained five times was calculated.
[0082]
(4) Water pressure resistance (barrier properties)
In accordance with A method (low water pressure method)
stipulated in JIS L 1096, the water pressure resistance of the
nonwoven fabric laminate was measured.
[0083]
(5) Measurement of cantilever value (flexural rigidity)
5 In accordance with JIS L1096 (6.19.1 A method), in a
constant temperature chamber at a temperature of 20f2"~an d a
humidityof 65+2% as specifiedin JIS 28703 (standardconditions
for testing), from the nonwoven fabric laminate, five test
pieces each 20 mm in width x 150 mm in length were collected
10 in the machine direction (MD). Each test piece was placed on
a horizontal, smooth-surface table having a 45" slope surface,
.with the shorter side of the test piece aligned at the scale
baseline. The test piece was slowly slid toward the slope
surfaceby hand. When the central point on one edge ofthe test
15 piece touched the slope surface, the length by which the other
edge hadmovedwas measuredby reading the scale. The flexural
rigidity was representedby length (mm) by which the test piece
had moved. Each of the five test pieces was tested on both the
front and back surfaces, and an average value was calculated.
20 Under the measurement so-called 45" cantilever method, the
nonwoven fabric with lower flexural rigidity is determined to
have more softness. In the use for clothing, when the flexural
rigidity value is 100 mm or less, the softness is determined
to be good. However, no limitation is necessarily made to this
value, since required softness vary depending on use purpose
and the l i k e .
[0084]
(6) Evaluation of fuzz resistance
5 From the nonwoven fabric laminate, 40 t e s t pieces each
having a size of 300 mm (longitudinal direction: MD) x 25 mm
(transverse direction: CD) were collected, and the fuzz
resistance was evaluated using an apparatus, "rubbing t e s t e r
I1 (Gakushin-type) " described i n JIS-L0849-2004, 5, 5.1, b.
10 Specifically, as such an apparatus, RT-100 manufactured by
DAIEIKAGAKUSEIKIMFG. Co.,Ltd.was employed. A200gfriction
block was used. A packing adhesive tape (cloth) No. 314
(manufactured by Rinrei Tape Co., Ltd.) was placed such that
the adhesive surface of the adhesive tape would rub the t e s t i n g
15 s u r f a c e o f t h e t e s t p i e c e . Topreventthetestpiecefrommoving
during the t e s t , sandpaper (No. 400) was f i t t e d t o a table of
the apparatus with the abrasive surface upward. The t e s t piece
was placed on the abrasive surface and was f i t t e d to the t e s t e r
table with the t e s t i n g surface upward. After the f i t t i n g of
20 the t e s t piece, the t e s t i n g surface of the t e s t piece and the
non-adhesive surface of the adhesive tape were rubbed against
each other back and forth 50times. The rubbed t e s t i n g surface
of the t e s t piece was observed, and the fuzz resistance was
graded based on the following c r i t e r i a .
1 point: There was no fuzz.
2 points: A small fuzzball started to form.
3 points: A recognizable fuzzball started to form, and
a plurality of small fuzzballs formed.
5 4 points: Recognizable large fuzzballs formed, and a
plurality of fibers started to lift.
5 points: Fibers were considerably torn off and the test
piece became thin.
6 points: Fibers were torn off and the test piece was
10 broken.
[0085]
(Example 1)

Amixtureof 50partsbyweightofametallocene-catalyzed
15 ethylene/l-hexene copolymer [manufacturedby Prime Polymer Co.,
Ltd., product name: EVOLUE H SP50800P, density: 0.951 g/cm3,
MFR: 135 g/10 min] and 50 parts by weight of a
metallocene-catalyzed ethylene-based polymer wax
[manufactured by Mitsui Chemicals, Inc., product name: EXCEREX
20 40800T, density: 0.980 g/cm3, weight average molecular weight:
6,9001 was molten, and the molten resin was discharged from a
spinneret with nozzles having 360 orifices with a diameter of
0.4 mm, at 0.7 y/min per a single orifice, and thereby melt
spinning by melt-blowing method was performed to form
microfibers. The microfibers were deposited on a collecting
surface, to produce a melt-blown nonwoven fabric (MB) having
I a basis weight of 40 g/m2.
5
An ethylene/l-butene copolymer [manufactured by Prime
Polymer Co., Ltd., product name: NEO-ZEX NZ50301, density:
0.950 g/cm3, MFR (measured in accordance with ASTM Dl238 at a
temperature of 190°C, under a load of 2.16 kg) : 30 g/10 min]
10 as a sheath-forming ethylene-based copolymer, and a
polyethyleneterephthalate [manufactured by Mitsui Chemicals,
Inc., product name: 51251 as a core-forming polyester-based
polymer, were extruded under spinning conditions in which the
discharge amount per a single orifice was 0.5 g/min/orifice and
15 the resin temperature was 270 "C. The filaments extruded were
cooled, and drawn such that the filaments had a fineness 2d.
The filaments were collected and heat-embossed. This method
providedaspunbondednonwovenfabric (SB) havingabasisweight
of 15 g/m2, formed from a concentric core-sheath conjugate fiber
20 (PE-based/PET conjugate) having a core percentage of 50% by
weight (core:sheath = 50:50 in weight ratio).
[0087]

On both surfaces of the melt-blown nonwoven fabric
4
obtained above, the spunbonded nonwoven fabric was stacked.
Then, the nonwoven fabrics were thermal fusion bonded to each
other by heat embossing (embossed area percentage: 18%) at 90 "C
at a linear pressure of 60 kg/cm, to obtain a three-layer
5 nonwoven fabric laminate. Properties of the resulting
nonwoven fabric laminate were measuredby the method described
above. Results are set forth in Table 1.
[0088]
(Example 2)
10 The melt-blown nonwoven fabric employed in Example 1 was
replaced with a mixture of 30 parts by weight of a
metallocene-catalyzed ethylene/l-hexene copolymer
[manufactured by Prime Polymer Co., Ltd., product name: EVOLUE
H SP50800P, density: 0.951 g/cm3, MFR: 135 9/10 min] and 70 parts
15 by weight of a Ziegler-catalyzed ethylene-based polymer wax
[manufacturedby Mitsui Chemicals, Inc., product name: Highwax
800P, density: 0.970 g/cm3, weight average molecular weight:
12,7001, and the same production procedure as in Example 1 was
performed, to obtain a three-layer nonwoven fabric laminate.
20 Properties of the resulting nonwoven fabric laminate were
measuredby themethods describedabove. Results are set forth
in Table 1.
[0089]
(Example 3)
The same procedure as in Example 1 was performed except
that the basis weight of the melt-blown nonwoven fabric was 30
g/m2r to obtain a three-layer nonwoven fabric laminate.
Properties of the resulting nonwoven fabric laminate were
5 measured by the method described above. Results are set forth
in Table 1.
[0090]
(Example 4)
The same procedure as in Example 1 was performed except
10 that the basis weight of the melt-blown nonwoven fabric was 20
g/m2, to obtain a three-layer nonwoven fabric laminate.
Properties of the resulting nonwoven fabric laminate were
measured by the method described above. Results are set forth
in Table 1.
15 [0091]
(Example 5)
The same procedure as in Example 1 was performed except
that the basis weight of the melt-blown nonwoven fabric was 10
g/m2r to obtain a three-layer nonwoven fabric laminate.
20 Properties of the resulting nonwoven fabric laminate were
measured by the method described above. Results are set forth
in Table 1.
[0092]
(Example 6)
The same procedure as in Example 1 was performed except
that a mixture of 30 parts by weight of a Ziegler-catalyzed
ethylene/l-butene copolymer [manufacturedbyprime Polymer Co.,
Ltd., product name: NEO-ZEXNZ50301, density: 0.950 g/cm3, MFR:
5 30 g/10 min) and 70 parts by weight of a metallocene-catalyzed
ethylene-based polymer wax [manufactured by Mitsui Chemicals,
Inc., product name: EXCEREX 408OOT, density: 0.980 g/cm3, weight
averagemolecularweight: 6,9001 wasusedtoobtainamelt-blown
nonwoven fabric having a basis weight 50 g/m2, to obtain a
10 three-layer nonwoven fabric laminate. Properties of the
resulting nonwoven fabric laminate were measured by the method
described above. Results are set forth in Table 1.
[0093]
(Example 7)
15 The nonwoven fabric laminate obtained in Example 1 was
irradiated with electron beam at 45 KGy, and allowed to stand
at 60 " C for 1 week, which was followed by measurement. Then,
properties ofthe nonwoven fabric laminate weremeasuredbythe
methods described above. Results are set forth in Table 1.
20 [0094]
(Example 8)
The same procedure as in Example 1 was performed except -
that a mixture of 40 parts by weight of the ethylene/l-butene
copolymer employed in Example 6 and 60 parts by weight of a
metallocene-catalyzed ethylene-based polymer wax (weight
averagemolecularweight: 6,900) was usedtoobtainamelt-blown
nonwoven fabric having a basis weight of 50 g/m2, to obtain a
three-layer nonwoven fabric laminate. Properties of the
5 resulting nonwoven fabric laminate were measured by the method
described above. Results are set forth in Table 1.
[0095]
(Example 9)
The same procedure as in Example 1 was performed except
10 that a mixture of 50 parts by weight of a Ziegler-catalyzed
ethylene/l-butene copolymer [Prime Polymer Co., Ltd.,
prototype, density: 0.935g/cm3, MFR: 150g/lOmin]) and50parts
byweightofametallocene-catalyzedethylene-basedpolymerwax
[manufactured by Mitsui Chemicals, Inc., product name: EXCEREX
15 40800T, weight average molecular weight: 6,9001 was used to
obtain a melt-blown nonwoven fabric having a basis weight of
40 g/m2, to obtain a three-layer nonwoven fabric laminate.
Properties of the resulting nonwoven fabric laminate were
measured by the method described above. Results are set forth
20 in Table 1.
[ 0 0 9 61
[Table 11

[0097]
(Example 10)
The same procedure as i n Example 1 was performed except
t h a t a m i x t u r e of 50 p a r t s byweight of ametallocene-catalyzed
5 ethylene/l-hexene copolymer [manufacturedbyprime Polymer Co.,
Ltd., product name: EVOLUE H SP50800P, d e n s i t y : 0.951 g/cm3,
MFR: 135 g/lOmin] and 50 p a r t s b y w e i g h t o f a Ziegler-catalyzed
ethylene-based polymer wax [manufactured by Mitsui Chemicals,
Inc., product name: Highwax 400P, d e n s i t y : 0.980 g/cm3, weight
10 averagemolecularweight: 6,8001 wasusedtoobtainamelt-blown
nonwoven f a b r i c having a b a s i s weight of 40 g/m2, t o obtain a
t h r e e - l a y e r nonwoven f a b r i c laminate. P r o p e r t i e s of t h e
r e s u l t i n g nonwoven f a b r i c laminate were measuredby the method
described above. Results are s e t f o r t h i n Table 2.
15 [0098]
(Example 11)
The same procedure as i n Example 1 was performed except
t h a t a mixture of 50 p a r t s by weight of
ethylene/l-butene copolymer [Prime Polymer Co., Ltd.:
20 prototype, density: 0.935 g/cm3, MFR: 150 g/10 min] and 50 p a r t s
by weight of a Ziegler-catalyzed ethylene-based polymer wax
[manufactured by Mitsui Chemicals, I n c . , product name:
Highwax 400P, d e n s i t y : 0.980 g/cm3, weight average molecular
weight: 6,8001 was used t o o b t a i n a melt-blown nonwoven f a b r i c
having a basis weight of 40 g/m2, to obtain a three-layer
nonwoven fabric laminate. Properties of the resulting
nonwoven fabric laminate weremeasured by the method described
above. Results are set forth in Table 2.
5 [0099]
(Example 12)
The same procedure as in Example 1 was performed except
that a mixture of 50 parts by weight of a Ziegler-catalyzed
ethylene/l-butene copolymer [Prime Polymer Co., Ltd.:
10 prototype, density: 0.935 g/cm3, MFR: 150 9/10 min] and 50 parts
by weight of a Ziegler-catalyzed ethylene-based polymer wax
[manufactured by Mitsui Chemicals, Inc., product name:
Highwax 400Pf density: 0.980 g/cm3, weight average molecular
weight: 6,8001 was used to obtain a melt-blown nonwoven fabric
15 having a basis weight of 15 g/m2, to obtain a three-layer
nonwoven fabric laminate. Properties of the resulting
nonwoven fabric laminate were measuredby themethod described
above. Results are set forth in Table 2.
20 (Comparative Example 1)
The same procedure as in Example 1 was performed except
that the spunbonded nonwoven fabric employed in Example 1 was
replaced with a spunbonded nonwoven fabric formed from a
concentriccore-sheathconjugatefiberhavingacorepercentage
of 20% by weight (core:sheath = 20:80 in weight ratio)
(PE-based/PP conjugate) of an ethylene/l-butene copolymer
[manufacturedbyprime Polymer Co., Ltd., product name: NEO-ZEX
NZ50301, density: 0.950 g/cm3, MFR (measured in accordance with
5 ASTM Dl238 at a temperature of 190°C under a load of 2.16 kg) :
30 9/10 min] serving as a sheath-forming ethylene-based
copolymer and a propylene polymer [manufactured by Mitsui
Chemicals, Inc., product name: S119, density: 0.910 g/cm3, MFR
(measured in accordance with ASTM Dl238 at a temperature of
10 230 "C under a load of 2.16 kg) : 60 g/10 min] serving as a
core-forming resin, to obtain a three-layer nonwoven fabric
laminate. The resulting nonwoven fabric laminate was
irradiated with electron beam at 45 KGy, and then was allowed
to stand at 60°C for 1 week, which was followed by measurement.
15 Then, properties of the nonwoven fabric laminate were measured
by the method described above. Results are set forth in ~abie
(Comparative Example 2)
20 The same procedure as in Example 12 was performed except
that the spunbonded nonwoven fabric employed in Example 12 was
replaced with the spunbonded nonwoven fabric formed from the
concentric core-sheath conjugate fiber (PE-based/PP
conjugate) employed in Comparative Example 1, to obtain a
three-layer nonwoven fabric laminate. The resulting nonwoven
fabric laminate was irradiated with electron beam at 45 KGy,
andallowedto standstillat 60'C forlweek, whichwas followed
by measurement. Properties of the nonwoven fabric laminate
5 were measured by the method described above. Results are set
forth in Table 2.
[0102]
(Comparative Example 3)
The same procedure as in Example 11 was performed except
10 that the spunbonded nonwoven fabric employed in Example 11 was
replaced with the spunbonded nonwoven fabric formed from the
concentric core-sheath conjugate fiber (PE-based/PP
conjugate) employed in Comparative Example 1, to obtain a
three-layer nonwoven fabric laminate. The resulting nonwoven
15 fabric laminate was irradiated with electron beam at 45 KGy,
and allowed to stand at 60°C for 1 week, which was followed by
measurement. Then, properties ofthe nonwoven fabric laminate
were measured by the method described above. Results are set
forth in Table 2.
20 [0103]
[Table 21
49
Table 2
Cantilever value
MDICD Mm 70145 70142 60140 91187 55/38 89/88
Fuzz resistance 1 1 1 4 4 4
In 'Table 1 and Table 2, it is demonstrated that the
nonwoven fabric laminate obtainedby laminatingthemelt-blown
nonwoven fabric (A) comprisingtheethylene-basedpolymerresin
5 composition, and the spunbondednonwoven fabric comprisingthe
conjugate fiber formed from the polyester (x) and the
ethylene-based polymer (y) such that part of the fiber surface
is the ethylene-based polymer (y) , even after irradiated with
electron beam, exhibits no reduction in tensile strength and
10 barrier properties, as is clear from the comparison between
Example 1 and Example 7. On the other hand, it is demonstrated
that the nonwoven fabric laminates obtained by laminatingthe
spunbonded nonwoven fabric comprising the PE-based/PP-based
conjugate fiber (Comparative Examples 1to 3), after irradiated
15 with electron beam, exhibits reduced tensile strength and
inferior barrier properties.
[0105]
In addition, it is clear from the comparison between
Example 4 and Example 6 or Example 8 that the reduction in the
20 average fiber diameter of the fibers forming the melt-blown
nonwoven fabric provides a nonwoven fabric laminate excellent
in barrier properties, even if the basis weight of the
melt-blown nonwoven fabric is reduced.
INDUSTRIAL APPLICABILITY
[0106]
The nonwoven fabric laminate of the present invention is
applicable to a whole range of sanitary materials, daily
5 commodities, industrial materials andmedicalmaterials. The
nonwoven fabric laminate of the present invention, which is
excellent particularly in softness, breathability and barrier
properties, is employable for various clothing uses, for
example disposable diapers, sanitary napkin, base cloth such
10 as poultices, materials for e.g., bed covers. The nonwoven
fabric laminate of the present invention, which is capable of
being disinfection/sterilization-treated with electron beam
or gamma ray, is stable particularly with respect to electron
beamor gamma rayappliedupon sterilization/disinfection, and
15 thus suitably employable as materials for gowns, caps, drapes,
masks, gauzes and various protecting clothes. Furthermore,
the nonwoven fabric laminate of the present invention, because
of its satisfactory after-processability such as
heat-scalability, is applicable to a whole range of daily
20 commodities includingoxygen scavengers, portablebodywarmers,
heated poultices, masks, uses for packaging various kinds of
powders, semi-solid, gel-likeorliquidsubstances, CD (compact
disk) bags, food packaging materials and clothing covers. For
the same reason, the nonwoven fabric laminate of the present
invention is s u i t a b l y employable f o r automotive i n t e r i o r s and
variousbackingmaterials. The nonwoven f a b r i c l a m i n a t e o f t h e
present invention, which is formed from f i n e f i b e r s , is widely
applicable as l i q u i d f i l t e r or a i r f i l t e r m a t e r i a l s .
5

CLAIMS
1. A nonwoven fabric laminate obtained by laminating
a spunbonded nonwoven fabric on at least one surface of a
melt-blown nonwoven fabric (A), the melt-blown nonwoven fabric
5 (A) comprising fibers of an ethylene-based polymer resin
composition of an ethylene-based polymer (a) and an
ethylene-basedpolymer wax (b), the spunbonded nonwoven fabric
comprising a conjugate fiber formed from a polyester (x) and
an ethylene-based polymer (y) such that at least part of the
10 fiber surface is the ethylene-based polymer (y).
2. The nonwoven fabric laminate according to Claim 1,
wherein the conjugate fiber is a concentric or eccentric
core-sheath type conjugate fiber composed of a core formed from
15 the polyester-based polymer (x) and a sheath formed from the
ethylene-based polymer (y), or a side-by-side type conjugate
fiber formed from the polyester-based polymer (x) and the
ethylene-based polymer (y) .
3 . The nonwoven fabric laminate according to Claim 1,
whichhas awaterpressure resistance of not less than 500mmAq.
4. . The nonwoven fabric laminate according to Claiml,
wherein the melt-blown nonwoven fabric (A) has a basis weight
5. The nonwoven fabric laminate according to Claim 1,
wherein fibers forming the melt-blown nonwoven fabric (A) have
5 an average fiber diameter of 0.5 to 8 pm.
6. The nonwoven fabric laminate according to any one
ofClaims1to 5, whereintheethylene-basedpolymercomposition
comprises an ethylene-based polymer (a) having a melt flow rate
10 of 10 to 250 9/10 min and an ethylene-based polymer wax (b) having
aweight averagemolecular weight of 6,000to15,000, ataweight
ratio of (a)/(b) in the range of 80/20 to 20/80.
7 . The nonwoven fabric laminate according to Claim 6,
15 wherein the ethylene-based polymer (a) comprises a
metallocene-catalyzed ethylene-based polymer.
8. The nonwoven fabric laminate according to Claim 6,
wherein the ethylene-based polymer wax (b) comprises a
20 metallocene-catalyzed ethylene-based polymer wax.
9. The nonwoven fabric laminate according to Claim 1,
wherein the ethylene-based polymer (a) has a melt flow rate of
50 to 150 g/10 min.
10. The nonwoven fabric laminate according to Claim 1,
wherein the ethylene-based polymer composition has a
half-crystallization time of not less than 87 sec.
5
11. The nonwoven fabric laminate according to Claim 1,
wherein the ethylene-based polymer composition comprises a
transition metal compound.
12. The nonwoven fabric laminate according to Claim 1,
which is bonded by thermal fusion bonding.
13. The nonwoven fabric laminate according to Claim 1,
which is capable of being sterilizedwith electronbeamor gamma
15 ray.
14. Anonwoven fabric for medical treatment comprising
the nonwoven fabric laminate according to any one of Claims 1
to 12.
15. A nonwoven fabric for packaging comprising the
nonwoven fabric laminate according to any one of Claims 1 to
12.
16. A nonwoven fabric for an absorbent article
comprising the. nonwoven fabric laminate according to any one
of Claims 1 to 12.
17. Amedical clothing comprising the nonwoven fabric
5 laminate according to any one of Claims 1 to 13.
18. A drape comprising the nonwoven fabric laminate
according to any one of Claims 1 to 13.
10 19. A medical clothing obtained by sterilizing the
nonwoven fabric laminate according to any one of Claims 1 to
13 through irradiation with electron beam or gamma ray.
20. Adrape obtainedbysterilizingthe nonwoven fabric
15 laminate according to any one of Claims 1 to 13 through
irradiation with electron beam or gamma ray.
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Dated this 1 1.09.2013
ATTORNEY FOR THE APPLICANTS