U.S. patent application number 11/665633 was filed with the patent office on 2008-04-10 for crimped filament-containing woven or knitted fabric with decreasing air space upon wetting with water, process for producing the same and textile products therefrom.
This patent application is currently assigned to TEIJIN FIBERS LIMITED. Invention is credited to Shigeru Morioka, Takeshi Yamaguchi, Satoshi Yasui, Masato Yoshimoto.
Application Number | 20080085398 11/665633 |
Document ID | / |
Family ID | 36203090 |
Filed Date | 2008-04-10 |
United States Patent
Application |
20080085398 |
Kind Code |
A1 |
Yasui; Satoshi ; et
al. |
April 10, 2008 |
Crimped Filament-Containing Woven Or Knitted Fabric With Decreasing
Air Space Upon Wetting With Water, Process For Producing The Same
And Textile Products Therefrom
Abstract
A woven or knitted fabric with a air space which is reversibly
decreased by wetting with water compared to its dry state,
comprises crimped filaments A whose percentage of crimp decreases
upon wetting with water, and filaments B selected from among
filaments with no crimps and crimped filaments which undergo
substantially no change in percentage of crimp upon wetting with
water, wherein the difference between the dry percentage of crimp
DC.sub.f(%) and the wet percentage of crimp (HC.sub.f)
(DC.sub.f-HC.sub.f) of a crimped filament A taken from the woven or
knitted fabric is at least 10%, and the average value RA between
the change in dimensions RP(%) of the woven or knitted fabric in
the warp (or wale) direction when wet and when dry, and the change
in dimensions RF(%) in the weft (or course) direction when wet and
when dry (=(RP-RF)/2)(%) is at least 5%.
Inventors: |
Yasui; Satoshi; (Osaka,
JP) ; Yamaguchi; Takeshi; (Osaka, JP) ;
Yoshimoto; Masato; (Ehime, JP) ; Morioka;
Shigeru; (Ehime, JP) |
Correspondence
Address: |
SUGHRUE MION, PLLC
2100 PENNSYLVANIA AVENUE, N.W.
SUITE 800
WASHINGTON
DC
20037
US
|
Assignee: |
TEIJIN FIBERS LIMITED
6-7, Minamihommachi 1-chome, Chuo-ku
Osaka
JP
541-0054
|
Family ID: |
36203090 |
Appl. No.: |
11/665633 |
Filed: |
October 17, 2005 |
PCT Filed: |
October 17, 2005 |
PCT NO: |
PCT/JP05/19432 |
371 Date: |
April 18, 2007 |
Current U.S.
Class: |
428/152 ; 28/247;
442/189; 442/308 |
Current CPC
Class: |
D10B 2501/04 20130101;
Y10T 442/425 20150401; D01D 5/32 20130101; D10B 2331/04 20130101;
A41B 2400/60 20130101; D03D 15/00 20130101; D03D 15/44 20210101;
D03D 15/47 20210101; D10B 2331/02 20130101; D04B 1/16 20130101;
D10B 2401/04 20130101; D10B 2331/10 20130101; D10B 2501/00
20130101; D03D 15/56 20210101; D10B 2503/06 20130101; Y10T
428/24446 20150115; D10B 2401/061 20130101; A41B 17/00 20130101;
Y10T 442/3065 20150401 |
Class at
Publication: |
428/152 ;
028/247; 442/189; 442/308 |
International
Class: |
D06N 7/04 20060101
D06N007/04; D02G 1/00 20060101 D02G001/00; D03D 15/00 20060101
D03D015/00; D04B 21/14 20060101 D04B021/14 |
Foreign Application Data
Date |
Code |
Application Number |
Oct 19, 2004 |
JP |
2004-304130 |
Claims
1. A woven or knitted fabric comprising crimped filaments A whose
percentage of crimp decreases upon wetting with water, and
filaments B composed of at least one type selected from among
filaments with no crimps and crimped filaments which undergo
substantially no change in percentage of crimp upon wetting with
water, characterized in that the percentage of crimp DC.sub.f(%) of
a sample of dry crimped filaments A prepared by allowing a sample
of said crimped filaments A taken from said woven or knitted fabric
to stand for 24 hours in an environment at a temperature of
20.degree. C., 65% RH, and the percentage of crimp HC.sub.f(%) of a
sample of the water wetted crimped filaments A prepared by
immersing a sample of said crimped filaments A in water at a
temperature of 20.degree. C. for 2 hours, lifting it out from the
water, sandwiching said sample between a pair of filter sheets
within 60 seconds of lifting it, subjecting it to a pressure of
0.69 mN/m.sup.2 for 5 seconds and lightly wiping the water from the
sample, satisfy the following requirement (1):
(DC.sub.f-HC.sub.f).gtoreq.10(%) (1), and in that the length LPD
(mm) in the warp (or wale) direction and the length LFD (mm) in the
weft (or course) direction for a sample of the dry woven or knitted
fabric prepared by taking a square sample with a 30 cm width in the
warp (or wale) direction and a 30 cm length in the weft (or course)
direction from the woven or knitted fabric and allowing it to stand
for 24 hours in an environment at a temperature of 20.degree. C.,
65% RH, and the length LPH (mm) in the warp (or wale) direction and
the length LFH (mm) in the weft (or course) direction for a sample
of the water wetted woven or knitted fabric prepared by immersing
said woven or knitted fabric sample in water at a temperature of
20.degree. C. for 2 hours, lifting it out from the water,
sandwiching said sample between a pair of filter sheets within 60
seconds of lifting it, subjecting it to a pressure of 0.69
mN/m.sup.2 for 5 seconds and lightly wiping the water from said
sample, are used in the following requirements (2) and (3):
RP(%)=((LPH-LPD)/LPD).times.100 (2)
RF(%)=((LFH-LFD)/LFD).times.100, (3) to calculate the change in
dimensions RP (%) representing the proportion of the difference
between the length when wet (LPH) and the length when dry (LPD)
with respect to the length when dry (LPD) for the warp (or wale)
direction of said woven or knitted fabric, and the change in
dimensions RF (%) representing the proportion of the difference
between the length when wet (LFH) and the length when dry (LFD)
with respect to the length when dry (LFD) for the weft (or course)
direction of said woven or knitted fabric, the average RA of which
satisfies the following requirement (4): RA(%)=(RP+RF)/2.ltoreq.5%,
(4) whereby the air space is reduced upon wetting with water.
2. A crimped filament-containing woven or knitted fabric which has
a decreased air space upon wetting with water according to claim 1,
wherein said crimped filaments A are selected from among crimped
conjugated fibers which differ from one another in terms of
water-absorbing and self-extending properties, are composed of a
polyester resin component and a polyamide resin component bonded in
a side-by-side fashion, and have crimps formed by expression of
their latent crimping performance.
3. A crimped filament-containing woven or knitted fabric which has
a decreased air space upon wetting with water according to claim 2,
wherein said polyester resin component is composed of a modified
polyethylene terephthalate resin comprising
5-sodiumsulfoisophthalic acid copolymerized in an amount of 2.0 to
4.5 mole percent based on the acid component content.
4. A crimped filament-containing woven or knitted fabric which has
a decreased air space upon wetting with water according to claim 1,
wherein said crimped filaments A are included in yarn twisted at
the number of twists of 0 to 300 T/m.
5. A crimped filament-containing woven or knitted fabric which has
a decreased air space upon wetting with water according to claim 1,
wherein said filaments B are formed of a polyester resin.
6. A crimped filament-containing woven or knitted fabric which has
a decreased air space upon wetting with water according to claim 1,
wherein said woven or knitted fabric has a multilayer woven or
knitted structure with two or more layers, wherein at least one
layer of said multilayer woven or knitted structure comprises said
crimped filaments A at a content of 30 to 100 wt % of the total
layer weight, and at least one other layer comprises said filaments
B at a content of 30 to 100 wt % of the total layer weight.
7. A crimped filament-containing woven or knitted fabric which has
a decreased air space upon wetting with water according to claim 1,
wherein said woven or knitted fabric is a knitted fabric with a
tubular knitting structure, the composite loops of which tubular
knitting structure are formed from said crimped filaments A and
filaments B.
8. A crimped filament-containing woven or knitted fabric which has
a decreased air space upon wetting with water according to claim 1,
wherein said woven or knitted fabric is a woven fabric with a weave
structure, wherein either or both of the warp and weft yarns are
composed of both paralleled yarns comprising yarn made of said
crimped filaments A and yarns made of said filaments B.
9. A crimped filament-containing woven or knitted fabric which has
a decreased air space upon wetting with water according to claim 1,
wherein the yarns made of said crimped filaments A and the yarns
made of said filaments B are arranged alternately with every one
yarn being in either or both the warp and weft direction or in
either or both the course and wale directions.
10. A crimped filament-containing woven or knitted fabric which has
a decreased air space upon wetting with water according to claim 1,
wherein the yarns made of said crimped filaments A and the yarns
made of said filaments B are combined with each other to form a
core-in-sheath type composite yarn, the core of said composite yarn
being composed of said filament B yarns and the sheath being
composed of said crimped filament A yarns.
11. A crimped filament-containing woven or knitted fabric which has
a decreased air space upon wetting with water according to claim 1,
wherein said filaments B are selected from among elastic fibers
with a breaking elongation of 300% or greater.
12. A crimped filament-containing woven or knitted fabric which has
a decreased air space upon wetting with water according to claim 1,
wherein the woven or knitted fabric has an air permeability upon
wetting with water which is at least 20% lower than the air
permeability upon drying.
13. A crimped filament-containing woven or knitted fabric which has
a decreased air space upon wetting with water according to claim 1,
which is a dyeing treatment applied fabric.
14. A crimped filament-containing woven or knitted fabric which has
a decreased air space upon wetting with water according to claim 1,
which is a water absorption treatment applied fabric.
15. A crimped filament-containing woven or knitted fabric which has
a decreased air space upon wetting with water according to claim 1,
which is a water repellent treatment applied fabric.
16. A process for production of a crimped filament-containing woven
or knitted fabric having a decreased air space upon wetting with
water, according to claim 1, the process being characterized by
comprising a step of producing a precursor woven or knitted fabric
from uncrimped fibers for formation of crimped filaments A which
express crimping by heat treatment and wherein the crimps have a
property such that the percentage of crimp decreases upon wetting
with water, and fibers for formation of filaments B comprising at
least one type selected from among fibers which do not express
crimping by said heat treatment, and fibers which express crimping
by said heat treatment but wherein the crimps have a property such
that the percentage of crimp substantially does not decrease upon
wetting with water, and a step wherein the precursor woven or
knitted fabric is subjected to heat treatment to form a woven or
knitted fabric containing the crimped filaments A and the filaments
B.
17. A process for production of a crimped filament-containing woven
or knitted fabric according to claim 16, wherein the fibers for
formation of said crimped filaments A are selected from among
uncrimped conjugated fibers made of a polyester resin component and
a polyamide resin component, which differ in their
moisture-absorbing and self-elongating properties and are combined
in a side-by-side structure.
18. A process for production of a crimped filament-containing woven
or knitted fabric according to claim 16, wherein the polyester
resin component in said uncrimped fibers includes a polyester resin
with an intrinsic viscosity of 0.30 to 0.43, and said polyamide
resin component includes a polyamide resin with an intrinsic
viscosity of 1.0 to 1.4.
19. A process for production of a crimped filament-containing woven
or knitted fabric according to claim 17, wherein said uncrimped
fibers have, after crimping treatment in boiling water, (1) a dry
percentage of crimp DC in the range of 1.5 to 13% after standing
for 24 hours in an environment at a temperature of 20.degree. C.,
65% RH, (2) a wet percentage of crimp HC in the range of 0.5 to
7.0% immediately after immersion in water at a temperature of
20.degree. C. for 2 hours, and (3) a difference between said dry
percentage of crimp DC and wet percentage of crimp HC (DC-HC) of
0.5% or greater.
20. A textile product including a crimped filament-containing woven
or knitted fabric with a decreased air space upon wetting with
water according to claim 1.
21. A textile product according to claim 21 which is selected from
among outerwear, sportswear and underwear.
Description
FIELD OF THE INVENTION
[0001] The present invention relates to a crimped
filament-containing woven or knitted fabric with a decreased air
space upon wetting with water, to a process for producing it, and
to textile products obtained therefrom. More specifically, the
invention relates to a woven or knitted fabric with a decreased air
space upon wetting with water and an increasing air space upon
drying, as well as to a process for producing it and to textile
products obtained therefrom.
BACKGROUND ART
[0002] Fabrics that undergo reversible change in air space by water
wetting and drying are known as moisture-sensitive fabrics, and
such moisture-sensitive fabrics having various structures have
recently been proposed.
[0003] For example, Japanese Unexamined Patent Publication No.
2003-41462 (Patent document 1) discloses an air-permeable
self-adjusting woven/knitted fabric comprising crimped conjugated
fibers obtained by heat treatment of conjugated fibers made of a
polyester resin component and a polyamide resin component bonded in
a side-by-side fashion, to produce crimps. In this woven/knitted
fabric, the percentage of crimp of the side-by-side crimped
conjugated fibers is reduced by water wetting, thereby increasing
the air space of the woven/knitted fabric and improving the air
permeability.
[0004] When swimming wear or sportswear manufactured from ordinary
woven/knitted fabrics made of synthetic or natural fibers is wetted
with water, the light permeability often increases and causes the
inner side to become visible, and therefore a solution to this
problem has been desired. Demand also exists for provision of
woven/knitted fabrics with reduced air space and improved
waterproof properties in response to water wetting. Yet, woven and
knitted fabrics that exhibit improved air permeability (increased
air space) by water wetting have reduced waterproof properties in
response to water wetting, and therefore cannot meet such
demands.
[0005] Patent document 1: Japanese Unexamined Patent Publication
No. 2003-41462
DISCLOSURE OF THE INVENTION
[0006] It is an object of the present invention to provide a
crimped filament-containing woven or knitted fabric with a lower
air space when wetted with water compared to its dry state, and an
increased air space upon drying, as well as a process for producing
it and to textile products obtained therefrom.
[0007] This object can be achieved by the woven/knitted fabric of
the invention, the process for producing it and its textile
products according to the invention.
[0008] The crimped filament-containing woven or knitted fabric of
the invention is a woven or knitted fabric comprising crimped
filaments A whose percentage of crimp decreases upon wetting with
water, and filaments B composed of at least one type selected from
among filaments with no crimps and crimped filaments which undergo
substantially no change in percentage of crimp upon wetting with
water,
[0009] characterized in that the percentage of crimp DC.sub.f(%) of
a sample of dry crimped filaments A prepared by allowing a sample
of the crimped filaments A taken from the woven or knitted fabric
to stand for 24 hours in an environment at a temperature of
20.degree. C., 65% RH, and the percentage of crimp HC.sub.f(%) of a
sample of the water wetted crimped filaments A prepared by
immersing a sample of the crimped filaments A in water at a
temperature of 20.degree. C. for 2 hours, lifting it out from the
water, sandwiching the sample between a pair of filter sheets
within 60 seconds of lifting it, subjecting it to a pressure of
0.69 mN/m.sup.2 for 5 seconds and lightly wiping the water from the
sample, satisfies the following requirement (1):
(DC.sub.f-HC.sub.f).gtoreq.10(%) (1), and in that the length LPD
(mm) in the warp (or wale) direction and the length LFD (mm) in the
weft (or course) direction for a sample of the dry woven or knitted
fabric prepared by taking a square sample with a 30 cm width in the
warp (or wale) direction and a 30 cm length in the weft (or course)
direction from the woven or knitted fabric and allowing it to stand
for 24 hours in an environment at a temperature of 20.degree. C.,
65% RH, and the length LPH (mm) in the warp (or wale) direction and
the length LFH (mm) in the weft (or course) direction for a sample
of the water wetted woven or knitted fabric prepared by immersing
the woven or knitted fabric sample in water at a temperature of
20.degree. C. for 2 hours, lifting it out from the water,
sandwiching the sample between a pair of filter sheets within 60
seconds of lifting it, subjecting it to a pressure of 0.69
mN/m.sup.2 for 5 seconds and lightly wiping the water from the
sample, are used in the following requirements (2) and (3):
RP(%)=((LPH-LPD)/LPD).times.100 (2)
RF(%)=((LFH-LFD)/LFD).times.100, (3) to calculate the change in
dimensions RP (%) representing the proportion of the difference
between the length when wet (LPH) and the length when dry (LPD)
with respect to the length when dry (LPD) for the warp (or wale)
direction of the woven or knitted fabric, and the change in
dimensions resizing factor RF (%) representing the proportion of
the difference between the length when wet (LFH) and the length
when dry (LFD) with respect to the length when dry (LFD) for the
weft (or course) direction of the woven or knitted fabric, the
average RA of which satisfies the following requirement (4):
RA(%)=(RP+RF)/2.ltoreq.5%, (4) whereby the air space is reduced by
wetting with water.
[0010] In the crimped filament-containing woven or knitted fabric
of the invention which has a decreased air space upon wetting with
water, preferably the crimped filaments A are selected from among
crimped conjugated fibers which differ from one another in terms of
water-absorbing and self-extending properties, which are composed
of a polyester resin component and a polyamide resin component
bonded in a side-by-side fashion, and which have crimps formed by
expression of their latent crimping performance.
[0011] Also, the polyester resin component in the crimped
filament-containing woven or knitted fabric of the invention which
has a decreased air space upon wetting with water is preferably
composed of a modified polyethylene terephthalate resin comprising
5-sodiumsulfoisophthalic acid copolymerized in an amount of 2.0 to
4.5 mole percent based on the acid component content.
[0012] The crimped filaments A in the crimped filament-containing
woven or knitted fabric of the invention which has a decreased air
space upon wetting with water are preferably used in yarn twisted
at the number of twists of 0 to 300 T/m.
[0013] The filaments B in the crimped filament-containing woven or
knitted fabric of the invention which has a decreased air space
upon wetting with water are preferably formed of a polyester
resin.
[0014] The woven or knitted fabric, of the crimped
filament-containing woven or knitted fabric of the invention which
has a decreased air space upon wetting with water, preferably has a
multilayer woven or knitted structure with two or more layers,
wherein at least one layer of the multilayer woven or knitted
structure comprises the crimped filaments A at a content of 30 to
100 wt % of the total layer weight, and at least one other layer
comprises the filaments B at a content of 30 to 100 wt % of the
total layer weight.
[0015] The woven or knitted fabric, of the crimped
filament-containing woven or knitted fabric of the invention which
has a decreased air space upon wetting with water, may be a knitted
fabric with a tubular knitting structure, the composite loops of
which tubular knitting structure are formed from the crimped
filaments A and filaments B.
[0016] The woven or knitted fabric, of the crimped
filament-containing woven or knitted fabric of the invention which
has a decreased air space upon wetting with water, may be a woven
fabric with a weave structure, wherein either or both the warp and
weft yarns may be composed of paralleled yarn comprising yarn made
of the crimped filaments A and yarn made of the filaments B.
[0017] In the woven or knitted fabric, of the crimped
filament-containing woven or knitted fabric of the invention which
has a decreased air space upon wetting with water, the yarns made
of the crimped filaments A and the yarns made of the filaments B
may be arranged alternately with every one yarn being in either or
both the warp and weft directions or in either or both the course
and wale directions.
[0018] In the crimped filament-containing woven or knitted fabric
of the invention which has a decreased air space upon wetting with
water, preferably the yarns made of the crimped filaments A and the
yarns made of the filaments B are combined with each other to form
a core-in-sheath type composite yarn, wherein the core of the
composite yarn is composed of the filament B yarns and the sheath
is composed of the crimped filament A yarns.
[0019] In the crimped filament-containing woven or knitted fabric
of the invention which has a decreased air space upon wetting with
water, preferably the filaments B are selected from among elastic
fibers with a breaking elongation of 300% or greater.
[0020] The woven or knitted fabric, of the crimped
filament-containing woven or knitted fabric of the invention which
has a decreased air space upon wetting with water, preferably has
an air permeability upon wetting with water which is at least 20%
lower than the air permeability upon drying.
[0021] The crimped filament-containing woven or knitted fabric of
the invention which has a decreased air space upon wetting with
water is preferably a dyeing treatment applied fabric.
[0022] The crimped filament-containing woven or knitted fabric of
the invention which has a decreased air space upon wetting with
water is also preferably a water absorption treatment applied
fabric.
[0023] The crimped filament-containing woven or knitted fabric of
the invention which has a decreased air space upon wetting with
water is also preferably a water repellent treatment applied
fabric.
[0024] The process for production of the crimped
filament-containing woven or knitted fabric of the invention is a
process for production of a crimped filament-containing woven or
knitted fabric which has a decreased air space upon wetting with
water, according to the present invention, the process being
characterized by comprising a step of producing a precursor woven
or knitted fabric from uncrimped fibers for formation of crimped
filaments A which express crimping by heat treatment and wherein
the crimps have a property such that the percentage of crimp
decreases upon wetting with water, and fibers for formation of
filaments B comprising at least one type selected from among fibers
which do not express crimping by the heat treatment, and fibers
which express crimping by the heat treatment but wherein the crimps
have a property such that the percentage of crimp substantially
does not decrease upon wetting with water, and a step wherein the
precursor woven or knitted fabric is subjected to heat treatment to
form a woven or knitted fabric containing the crimped filaments A
and the filaments B.
[0025] In the process for production of the crimped
filament-containing woven or knitted fabric of the invention,
preferably the fibers for formation of the crimped filaments A are
selected from among uncrimped conjugated fibers made of a polyester
resin component and a polyamide resin component, which differ in
their moisture-absorbing and self-elongating properties and are
combined in a side-by-side structure.
[0026] In the process for production of the crimped
filament-containing woven or knitted fabric of the invention,
preferably the polyester resin component in the uncrimped fibers
includes a polyester resin with an intrinsic viscosity of 0.30 to
0.43, and the polyamide resin component includes a polyamide resin
with an intrinsic viscosity of 1.0 to 1.4.
[0027] In the process for production of the crimped
filament-containing woven or knitted fabric of the invention,
preferably the uncrimped fibers have, after crimping treatment in
boiling water, (1) a dry percentage of crimp DC in the range of 1.5
to 13% after standing for 24 hours in an environment at a
temperature of 20.degree. C., 65% RH,
[0028] (2) a wet percentage of crimp HC in the range of 0.5 to 7.0%
immediately after immersion in water at a temperature of 20.degree.
C. for 2 hours, and
[0029] (3) a difference between the dry percentage of crimp DC and
wet percentage of crimp HC (DC-HC) of 0.5% or greater.
[0030] A textile product of the invention includes a crimped
filament-containing woven or knitted fabric of the invention which
has a decreased air space upon wetting with water.
[0031] The textile product of the invention is preferably selected
from among outer garments, sportswear and underwear.
[0032] A woven or knitted fabric of the invention has an air space
which decreases by wetting with water and increases by drying, and
therefore the visibility is not greater upon wetting, such as
wetting caused by sweat, and the waterproof property of the woven
or knitted fabric in rain, for example, is improved. A crimped
filament-containing woven or knitted fabric of the invention is
therefore useful for outer garments, sportswear and inner clothing
materials.
BRIEF DESCRIPTION OF THE DRAWINGS
[0033] FIG. 1 is a cross-sectional view showing the structure of an
example of a crimped filament whose percentage of crimp decreases
upon wetting with water, in a woven or knitted fabric of the
invention.
[0034] FIG. 2 is a cross-sectional view showing the structure of
another example of a crimped filament whose percentage of crimp
decreases upon wetting with water, in a woven or knitted fabric of
the invention.
[0035] FIG. 3 is a cross-sectional view showing the structure of
still another example of a crimped filament whose percentage of
crimp decreases upon wetting with water, in a woven or knitted
fabric of the invention.
BEST MODE FOR CARRYING OUT THE INVENTION
[0036] A woven or knitted fabric of the invention comprises crimped
filaments A whose percentage of crimp decreases upon wetting with
water, and filaments B composed of at least one type selected from
among filaments with no crimps and crimped filaments which undergo
substantially no change in percentage of crimp upon wetting with
water. When a woven or knitted fabric of the invention is wetted
by, for example, sweat or rain, the crimped filaments A undergo a
decrease in percentage of crimp and their apparent lengths are
extended. On the other hand, the filaments B undergo essentially no
change in percentage of crimp due to wetting and therefore exhibit
no change in apparent length, so that the woven or knitted fabric
dimensions are virtually unaltered. Consequently, the air space of
the woven or knitted fabric is reduced by the crimped filaments A
whose apparent lengths have been increased. When the woven or
knitted fabric is dried, however, there is virtually no change in
the crimping or apparent lengths of the filaments B, while the
crimped filaments A increase their percentage of crimp and exhibit
a shortening of their apparent lengths, thereby increasing the air
space of the woven or knitted fabric.
[0037] In order for a woven or knitted fabric of the invention to
exhibit a decreased air space upon wetting with water, it is
essential that the percentage of crimp DC.sub.f(%) of a sample of
dry crimped filaments A prepared by allowing a sample of the
crimped filaments A taken from the woven or knitted fabric to stand
for 24 hours in an environment at a temperature of 20.degree. C.,
65% RH, and the percentage of crimp HC.sub.f(%) of a sample of the
water wetted crimped filaments A prepared by immersing a sample of
the crimped filaments A in water at a temperature of 20.degree. C.
for 2 hours, lifting it out from the water, sandwiching the sample
between a pair of filter sheets within 60 seconds of lifting it,
subjecting it to a pressure of 0.69 mN/m.sup.2 for 5 seconds and
lightly wiping the water from the sample, satisfy the following
requirement (1): (DC.sub.f-HC.sub.f).gtoreq.10(%) (1), and that
when the length LPD (mm) in the warp (or wale) direction and the
length LFD (mm) in the weft (or course) direction are measured for
a sample of the dry woven or knitted fabric prepared by taking a
square sample with a 30 cm width in the warp (or wale) direction
and a 30 cm length in the weft (or course) direction from the woven
or knitted fabric and allowing the woven or knitted fabric sample
to stand for 24 hours in an environment at a temperature of
20.degree. C., 65% RH, and the length LPH (mm) in the warp (or
wale) direction and the length LFH (mm) in the weft (or course)
direction are measured for a sample of the water wetted woven or
knitted fabric prepared by immersing the woven or knitted fabric
sample in water at a temperature of 20.degree. C. for 2 hours,
lifting it out from the water, sandwiching the sample between a
pair of filter sheets within 60 seconds of lifting it, subjecting
it to a pressure of 0.69 mN/m.sup.2 for 5 seconds and lightly
wiping the water from the sample, and the values for LPD, LFD, LPH
and LFH are used in the following requirements (2) and (3):
RP(%)=((LPH-LPD)/LPD).times.100 (2)
RF(%)=((LFH-LFD)/LFD).times.100, (3) to calculate the change in
dimensions RP (%) representing the proportion of the difference
between the length when wet (LPH) and the length when dry (LPD)
with respect to the length when dry (LPD) for the warp (or wale)
direction of the woven or knitted fabric, and the change in
dimensions RF (%) representing the proportion of the difference
between the length when wet (LFH) and the length when dry (LFD)
with respect to the length when dry (LFD) for the weft (or course)
direction of the woven (or knitted) fabric, the average RA thereof
satisfies the following requirement (4): RA(%)=(RP+RF)/2.ltoreq.5%.
(4)
[0038] The value of (DC.sub.f-HC.sub.f) is preferably 15 to 30%,
and the RA value is preferably 1 to 3%. If the (DC.sub.f-HC.sub.f)
value is less than 10% and/or the RA value is larger than 5%,
elongation of the woven or knitted fabric as a whole will absorb
the extension in apparent lengths of the crimped filaments A by the
reduction in percentage of crimp of the crimped filaments A when
the woven or knitted fabric is wetted with water, thus preventing
reduction in the air space of the woven or knitted fabric.
[0039] The percentage of crimp of the crimped filaments A in the
woven or knitted fabric is measured by the following method.
[0040] A test woven or knitted fabric is allowed to stand for 24
hours in an atmosphere at a temperature of 20.degree. C., 65% RH
and then 30 cm.times.30 cm strips are cut from the woven or knitted
fabric in the same direction as the woven or knitted fabric (n=5).
Crimped filaments A are removed from each of the strips and
subjected to a load of 1.76 mN/dtex (200 mg/de) and the filament
lengths L0f are measured, and then after 1 minute of releasing the
load, a load of 0.0176 mN/dtex (2 mg/de) is applied and the
filament lengths L1f are measured. Also, the filaments are immersed
for 2 hours in water at a temperature of 20.degree. C. and then
removed and the water is wiped off gently with filter paper, after
which a load of 1.76 mN/dtex (200 mg/de) is applied, the filament
lengths L0f' are measured, and then after 1 minute of releasing the
load, a load of 0.0176 mN/dtex (2 mg/de) is applied and the
filament lengths L1f' are measured. The measured values are used in
the following formulas to calculate the percentage of crimp when
dry DCf(%), the percentage of crimp when wet HCf(%) and the
difference in percentages of crimp when dry and when wet
(DCf-HCf)(%). The average of the number n (5) is calculated. Dry
percentage of crimp DCf(%)=((L0f-L1f)/L0f).times.100 Wet percentage
of crimp HCf(%)=((L0f'-L1f')/L0f').times.100 It is essential for
the crimped filaments A taken from the woven or knitted fabric to
be crimped filaments wherein the difference between the dry
percentage of crimp DC(%) and wet percentage of crimp HC(%) (DC-HC)
is at least 10%.
[0041] Such crimped filaments A are preferably selected from among
crimped conjugated fibers which differ from one another in terms of
water-absorbing and self-extending properties, are composed of a
polyester resin component and a polyamide resin component bonded in
a side-by-side fashion, and have crimps formed by expression of
their latent crimping performance.
[0042] As polyester resin components to be used for the conjugated
fibers there are preferred those having high adhesion with the
aforementioned polyamide resin component, and for example, there
are preferably used modified polyesters such as polyethylene
terephthalate, polypropylene terephthalate or polybutylene
terephthalate which are copolymerized with compounds which have an
alkali or alkaline earth metal or phosphonium salt of sulfonic
acid, and which have one or more functional groups with
ester-forming capability. Particularly preferred among these are
modified polyethylene terephthalate copolymerized with the
aforementioned compounds because of their general purpose utility
and low polymer cost. Examples of copolymerizing components in this
case include 5-sodiumsulfoisophthalic acid and its ester
derivatives, 5-phosphoniumisophthalic acid and its ester
derivatives, sodium p-hydroxybenzenesulfonate, and the like.
Preferred among these is 5-sodiumsulfoisophthalic acid. The
copolymerization content is preferably in the range of 2.0 to 4.5
mole percent with respect to the moles of the acid component in the
polyester resin. If the copolymerization content is less than 2.0
mole percent, excellent crimping performance is exhibited but
peeling may occur at the bonding interface between the polyamide
resin component and polyester resin component. Conversely, if the
copolymerization content is greater than 4.5 mole percent,
crystallization of the polyester resin component will be inhibited
during stretching heat treatment, thus requiring a higher
stretching heat treatment temperature level than usual, and
potentially leading to numerous yarn breaks.
[0043] On the other hand, the polyamide resin component is not
particularly restricted so long as it has an amide bond in the main
chain, and as examples there may be mentioned nylon-4, nylon-6,
nylon-66, nylon-46 and nylon-12. Among these nylon-6 and nylon-66
are particularly preferred from the viewpoint of general utility,
polymer cost and reeling stability.
[0044] The polyester resin component and polyamide resin component
may also contain publicly known additives such as pigments,
delustering agents, anti-fouling agents, fluorescent brighteners,
flame retardants, stabilizers, antistatic agents, light fastness
agents, ultraviolet absorbers and the like.
[0045] There are no particular restrictions on the cross-sectional
profile of side-by-side conjugated fibers for the crimped filaments
A, and the bonding line between the polyester resin component and
the polyamide resin component in the cross-sectional shape may be
essentially straight linear or a completely straight line. Examples
of cross-sectional shapes for the conjugated fibers are shown in
FIGS. 1 to 3. In FIG. 1, the conjugated fiber 1 has a circular
cross-sectional profile and is composed of a polyester resin
component 2 and polyamide resin component 3 bonded together, with
an essentially straight linear bonding line. In FIG. 2, the
conjugated fiber 1 has an oval cross-sectional profile and is
composed of a polyester resin component 2 and polyamide resin
component 3 bonded together, with an essentially straight linear
bonding line. In FIG. 3, the conjugated fiber 1 has a circular
cross-sectional shape and is composed of a polyester resin
component 2 and polyamide resin component 3 bonded together, but
the polyamide resin component 3 has a roughly circular
cross-sectional profile and is situated in the polyester resin
component also having a roughly circular cross-sectional profile,
in a positional relationship approximating an eccentric
core-in-sheath structure. However, a portion of the periphery of
the polyamide resin component 3 is exposed and forms a part of the
periphery of the conjugated fiber.
[0046] The cross-sectional profile of the conjugated fiber may be,
instead of circular or oval, polygonal such as triangular or
rectangular, or star-shaped or even hollow. However, the
cross-sectional profile of the conjugated fiber is preferably
circular in order to efficiently decrease the percentage of crimp
upon wetting with water.
[0047] The weight ratio of the two resin components in the
conjugated fibers for the crimped filaments A is not particularly
restricted, but the weight ratio of the polyester resin component
with respect to the polyamide resin component is preferably in the
range of 30:70 to 70:30 and more preferably 40:60 to 60:40.
[0048] There are no particular restrictions on the individual
filament thickness of the crimped filaments A or on the number of
individual filaments of the crimped filaments A contained in the
crimped filament yarn, but the individual filament thickness is
preferably 1 to 10 dtex and more preferably 2 to 5 dtex. The number
of individual filaments in the crimped filament A yarns is
preferably 10 to 200 and more preferably 20 to 100.
[0049] Uncrimped side-by-side conjugated fibers composed of two
different resin components as described above have a latent
crimping property, and therefore express crimps when subjected to
heat treatment such as, for example, high-temperature dyeing
treatment. In such crimped conjugated fibers, preferably the
polyamide resin component is situated on the inner portions of the
crimps, while the polyester resin component is situated on the
outer portions of the crimps. When crimped conjugated fibers having
such a crimp structure are wetted with water, the polyamide resin
component situated on the inner portions of the crimps are swelled
by the water and expand while the polyester resin component
situated on the outer portions of the crimps do not swell with
water and their lengths are unchanged, such that the percentage of
crimp of the conjugated fibers is reduced, and the apparent lengths
increase. On the other hand, when the water-wetted crimped
conjugated fibers are dried, the polyamide resin component shrinks
while the polyester resin component undergoes no change in length,
such that the percentage of crimp of the conjugated fibers
increases and the apparent length of the crimped conjugated fibers
is shortened.
[0050] The crimped filaments A are preferably in untwisted yarn or
false twisted yarn with no more than 300 T/m twists, in order to
facilitate reduction in the percentage of crimp and lengthening
upon wetting with water. Untwisted filaments are especially
preferred. With strong twisted yarn having strong twisting with
greater than 300 T/m, the crimping is sometimes reduced upon
wetting with water.
[0051] Also, yarn comprising the crimped filaments may be subjected
to, for example, interlacing air treatment and/or false twisting
treatment, and such treatment may cause interlacing of the
individual filaments in the yarn at an interlacing number of about
20 to 60/m.
[0052] As long as the aforementioned conditions are satisfied,
there are no particular other restrictions on the type of filaments
B used in a woven or knitted fabric of the invention, i.e. the
filaments which are uncrimped and undergo essentially no change in
percentage of crimp upon wetting with water. Here, the phrase
"undergo essentially no change in percentage of crimp upon wetting
with water" means that the dry percentage of crimp DC(%) when the
filaments are dried under the conditions described above and the
wet percentage of crimp HC(%) when they are wetted with water under
the conditions described above (DC-HC) is less than 0.5(%).
[0053] The filaments B used for a woven or knitted fabric of the
invention include filaments suitable for clothing, and may be
polyesters such as polyethylene terephthalate, polytrimethylene
terephthalate and polybutylene terephthalate, polyamides such as
nylon-6 and nylon-66, polyolefins such as polyethylene and
polypropylene, synthetic filaments formed from acrylic compounds,
para- or meta-aramids and their modified synthetic resins, natural
fibers, regenerated fibers, semi-synthetic fibers,
polyurethane-based elastic fibers and polyether ester-based elastic
fibers. Preferred among these are polyethylene terephthalate,
polypropylene terephthalate and polybutylene terephthalate, as well
as polyester filaments composed of modified polyesters obtained by
copolymerization of these with copolymerizing components, because
of their high dimensional stability when wet and their excellent
compatibility with the crimped filaments A (combined filament
properties, mixed knitting or mixed weaving properties and dyeing
properties). There are also no particular restrictions on the
individual filament thickness of the filaments B or on the number
of individual filaments (number of filaments) in yarn comprising
the filaments B, but for increased hygroscopicity of the woven or
knitted fabric and further improved performance of air permeability
when wet, the individual filament thickness is preferably 0.1 to 5
dtex (more preferably 0.5 to 2 dtex) and the number of filaments
per yarn is preferably in the range of 20 to 200 and more
preferably 30 to 100. The yarn comprising the filaments B can be
subjected to interlacing air treatment and/or ordinary false
twisting treatment. Such treatment may cause interlacing of the
individual filaments in the yarn at an interlacing number of about
20 to 60/m.
[0054] A woven or knitted fabric of the invention comprises the
aforementioned crimped filaments A whose percentage of crimp
decreases upon wetting with water, and filaments B made of
uncrimped filaments and/or filaments which undergo essentially no
change in percentage of crimp upon wetting. Both may be used as
separate yarns to form the woven or knitted fabric, or they may
form the woven or knitted fabric as combined filament yarn such as
air-mixed yarn, double twisted yarn, combined false twisted crimped
yarn, paralleled yarn and the like.
[0055] There are no particular restrictions on the texture or
number of layers for production of a woven or knitted fabric. For
example, there may be suitably used a woven texture such as a plane
weave, twill weave or satin weave, or a knitted texture such as a
plain stitch, smooth knit, circular rib knit, seed stitch, plating
stitch, Denbigh stitch, half knit or the like. However, there is no
limitation to these. The layer structure for composing a woven or
knitted fabric may be single-layer or multilayer with two or more
layers.
[0056] Modes of woven or knitted fabrics include:
[0057] (1) woven or knitted fabrics having a multilayer woven or
knitted structure of two or more layers wherein at least one of the
layers of the multilayer woven or knitted structure comprises the
crimped filaments A at a content of 30 to 100 wt % of the total
weight of the layer, and at least one other layer comprises the
filaments B at a content of 30 to 100 wt % of the total weight of
the layer,
[0058] (2) knitted fabrics having a tubular knitting structure,
with the composite loops of the tubular knitting structure formed
from both the crimped filaments A and filaments B,
[0059] (3) woven fabrics having a woven texture, wherein either or
both the warp and weft yarn is composed of paralleled yarn
comprising yarn made of the crimped filaments A and yarn made of
the filaments B.
[0060] (4) woven or knitted fabrics wherein the yarns made of the
crimped filaments A and the yarns made of the filaments B are
arranged alternately with every one yarn being in either or both
the warp and weft directions or in either or both the course and
wale directions.
[0061] (5) woven or knitted fabrics wherein the yarns made of the
crimped filaments A and the yarns made of the filaments B are
combined together to form a core-in-sheath type composite yarn,
wherein the core of the conjugated yarn is composed of the filament
B yarns and the sheath is composed of the crimped filament A
yarns.
[0062] In the composite yarn having a core-in-sheath structure for
mode (5) described above, it is important for the length LA of the
sheath yarn made of the crimped filaments A and the length LB of
the core yarn made of the filaments B to satisfy the relational
expression: LA>LB. That is, if LA.ltoreq.LB, wetting of the
obtained woven or knitted fabric will cause a reduced percentage of
crimp for the crimped filaments A from which the sheath is formed,
and when the apparent length is increased the filament B yarns from
which the core is formed will also be elongated due to stretching
by the elongated crimped filament A sheath yarn, eventually
creating a change in dimensions in the woven or knitted fabric as a
whole; thus, decrease in the percentage of crimp and increase in
the apparent length of the crimped filaments A will not contribute
to a reduced the air space of the woven or knitted fabric as a
whole. The aforementioned relational expression LA>LB can be
satisfied by (1) a method wherein a high heat-shrinkage yarn with a
boiling water shrinkage of 20% or greater is used as the core
filament B yarns for production of composite yarn comprising the
crimped filament A yarns for the sheath and the high heat-shrinkage
filament B yarns for the core, a precursor woven or knitted fabric
is produced from this composite yarn, and the precursor woven or
knitted fabric is subjected to heat shrinkage treatment for heat
shrinkage of the filament B yarns in order to achieve the
expression LA>LB, and (2) a method wherein elastic filaments are
used as the filament B yarns and these are mixed or paralleled with
the crimped filaments A with the elastic filaments B in an
elongated state to produce a precursor core-in-sheath composite
yarn, after which the elongation is removed from the precursor
composite yarn, elastic shrinkage is produced in the elastic
filaments B to achieve the expression LA>LB, and a woven or
knitted fabric is produced from the core-in-sheath composite
yarn.
[0063] In a woven or knitted fabric of the invention, the lengths
LA and LB of the core yarn and sheath yarn in the core-in-sheath
composite yarn may be measured by the following method.
[0064] A test woven or knitted fabric is allowed to stand for 24
hours in an environment at a temperature of 20.degree. C., 65% RH,
a sample with a 30 cm length in the warp (or wale) direction and a
30 cm width in the weft (or course) direction is taken from the
woven or knitted fabric, and then a crimped filament A yarn and
filament B yarn are taken from core-in-sheath composite yarn
oriented in the same direction. The length LA of the crimped
filament A yarn is measured under a load of 1.76 mN/dtex, and the
length LB of the filament B yarn is measured under a load of 1.76
mN/dtex if it is a non-elastic filament yarn with a breaking
elongation of up to 200%, or under a load of 0.0088 mN/dtex if it
is an elastic filament yarn with a high breaking elongation
exceeding 20%.
[0065] The elastic filaments used as filaments B in a woven or
knitted fabric of the invention preferably have a breaking
elongation of 300% or greater.
[0066] The process for producing a woven or knitted fabric of the
invention comprises a step of producing a precursor woven or
knitted fabric from uncrimped fibers for formation of crimped
filaments A which express crimping by heat treatment and wherein
the crimps have a property such that the percentage of crimp
decreases upon wetting with water, and fibers for formation of
filaments B comprising at least one type selected from among fibers
which do not express crimping by the heat treatment, and fibers
which express crimping by the heat treatment but wherein the crimps
have a property such that the percentage of crimp substantially
does not decrease upon wetting with water, and a step wherein the
precursor woven or knitted fabric is subjected to heat treatment to
form a woven or knitted fabric containing the crimped filaments A
and the filaments B.
[0067] In the process of the invention, preferably the fibers for
formation of the crimped filaments A are selected from among
uncrimped conjugated fibers made of a polyester resin component and
a polyamide resin component, which differ in their
moisture-absorbing and self-extending properties and are bonded in
a side-by-side fashion. Also, preferably the polyester resin
component of the uncrimped fibers includes a polyester resin with
an intrinsic viscosity of 0.30 to 0.43, and the polyamide resin
component includes a polyamide resin with an intrinsic viscosity of
1.0 to 1.4. The intrinsic viscosity of the polyester resin
component of the uncrimped fibers is more preferably 0.35 to 0.40
and the intrinsic viscosity of the polyamide resin is more
preferably 1.2 to 1.4. The intrinsic viscosity of the polyester
resin is measured at a temperature of 35.degree. C. with
ortho-chlorophenol as the solvent, and the intrinsic viscosity of
the polyamide resin is measured at a temperature of 30.degree. C.
with m-cresol as the solvent.
[0068] In the aforementioned production process, an intrinsic
viscosity of the polyester resin component higher than 0.43 yields
a conjugated fiber with physical properties similar to fiber
composed of a polyester resin component alone, and can prevent
reduction in the air space when the woven or knitted fabric is
wetted with water. Also, an intrinsic viscosity of the polyester
resin component of less than 0.30 excessively reduces the viscosity
of the molten polyester resin component during the melt spinning
step, resulting in insufficient fiber formability, increased
generation of fluff in the obtained conjugated fibers, and
inadequate quality and production efficiency for the conjugated
fibers.
[0069] The spinneret used to produce the side-by-side conjugated
filaments A may be one as shown in FIG. 1 of Japanese Unexamined
Patent Publication No. 2000-144518. The extrusion openings for the
high viscosity resin component and the extrusion openings for the
low viscosity resin component in this spinneret are separated, in a
design wherein the cross-sectional area of the extrusion openings
for the high viscosity resin is increased to lower the extrusion
rate. This type of spinneret is used for passage of the molten
polyester resin component through the high viscosity resin
extrusion openings and passage of the molten polyamide resin
component through the low viscosity resin extrusion openings,
joining the two types of melt flows in a side-by-side fashion and
cooling them to solidification. In this melt spinning step, the
weight ratio of the polyester resin component with respect to the
polyamide resin component is preferably 30:70 to 70:30, and more
preferably 40:60 to 60:40.
[0070] For production of the aforementioned side-by-side conjugated
fibers, the unstretched fiber yarns (bundled) produced in the melt
spinning step may be first wound up and then supplied to a
stretching step (separate stretching), or the melt spun unstretched
filament yarns (unbundled) may be supplied directly to a stretching
heat treatment step without winding up (direct stretching). The
stretching step may be carried out under ordinary conditions. For
example, in a direct stretching system, the spinning step is
carried out at a spinning speed of 1000 to 3500 m/min, and the
obtained unstretched fiber yarn is immediately stretched at a
desired draw ratio at a temperature of 100 to 150.degree. C. and
wound up. The draw ratio is appropriately set so that the finally
obtained conjugated fiber has a breaking elongation of preferably
10 to 60% and more preferably 20 to 45%, and a tensile strength of
preferably 3.0 to 4.7 cN/dtex and more preferably 3.0 to 4.0
cN/dtex.
[0071] The uncrimped fibers of the conjugated fibers for the
crimped filament A obtained by the production process of the
invention preferably have, after crimping treatment in boiling
water,
[0072] (1) a dry percentage of crimp DC in the range of 1.5 to 13%
after standing for 24 hours in an environment at a temperature of
20.degree. C., 65% RH,
[0073] (2) a wet percentage of crimp HC in the range of 0.5 to 7.0%
immediately after immersion in water at a temperature of 20.degree.
C. for 2 hours, and
[0074] (3) a difference between the dry percentage of crimp DC and
wet percentage of crimp HC (DC-HC) of 0.5% or greater.
[0075] The dry percentage of crimp DC and wet percentage of crimp
HC are measured by the following methods.
[0076] A wind-up frame with a circumference of 1.125 m is used for
rewinding under a load of 49/50 mN.times.9.times.total tex (0.1
gf.times.total denier) at a fixed speed for 10 winds to produce a
small skein, the small skein is twisted into a double ring and
placed in boiling water while subjected to an initial load of
49/2500 mN.times.20.times.9.times.total tex (2
mg.times.20.times.total denier) for 30 minutes of treatment, after
which it is dried for 30 minutes with a drier at 100.degree. C. and
then placed in dry heat at 160.degree. C. while subjected to the
initial load for 5 minutes of treatment. The initial load is
removed after the dry heat treatment, and after standing for at
least 24 hours in an environment at a temperature of 20.degree. C.,
65% RH, the initial load and 98/50 mN.times.20.times.9.times.total
tex (0.2 gf.times.20.times.total denier) double load are applied,
the skein length L0 is measured, the double load alone is
immediately removed, and the skein length L1 one minute after
removing the load is measured. The skein is then immersed for 2
hours in water at a temperature of 20.degree. C. while under the
initial load, and after removal and lightly wiping off the water
with filter paper, it is subjected to the initial load and the
double load, the skein length L0' is measured, the double load
alone is immediately removed, and the skein length L1' one minute
after removing the load is measured. These measured values are
inserted into the following formula to calculate the dry percentage
of crimp (DC), wet percentage of crimp (HC) and the difference in
dry and wet percentage of crimps (DC-HC). Dry percentage of crimp
DC(%)=((L0-L1)/L0).times.100 Wet percentage of crimp
HC(%)=((L0'-L1')/L0').times.100
[0077] When the dry percentage of crimp of the conjugated fiber is
smaller than 1.5%, the change in percentage of crimp when wet is
reduced, and therefore the change in air permeability of the woven
or knitted fabric may be smaller. Conversely, when the dry
percentage of crimp of the conjugated fiber is greater than 13%,
crimping is strong enough to inhibit change in crimping when wet,
and the change in air permeability of the woven or knitted fabric
may likewise be smaller. If the difference in percentage of crimp
of the conjugated fiber when dry and when wet (DC-HC) is less than
0.5%, the change in air permeability of the woven or knitted fabric
may be excessively small.
[0078] In the process for production of a woven or knitted fabric
of the invention, the aforementioned uncrimped conjugated fibers,
and the filaments B which are uncrimped with a hot water shrinkage
of 20% or greater or crimped with a percentage of crimp which is
essentially unchanged upon wetting, are used to weave or knit a
precursor woven or knitted fabric, which is then subjected to
dyeing wherein the heat of dyeing produces crimps in the conjugated
fibers to produce a woven or knitted fabric containing crimped
filaments A. When a core-in-sheath type composite yarn is obtained
using the crimped conjugated filament A yarn and the filament B
yarn, it is important for the length LA of the crimped filament A
yarn to be larger than the length LB of the filament B yarn in the
composite yarn.
[0079] There are no special restrictions on the woven or knitted
texture of a woven or knitted fabric according to the
invention.
[0080] In the production process of the invention, the temperature
for the dyeing treatment is preferably 100 to 140.degree. C. and
more preferably 110 to 135.degree. C., and the dyeing time is
preferably in the range of from 5 to 40 minutes as the keep time at
the top temperature. Dyeing of the woven or knitted fabric under
these conditions will allow the uncrimped conjugated fibers to
express crimping by the heat shrinkage difference between the
polyester resin component and the polyamide resin component. The
polyester resin component and polyamide resin component may be
selected from among the aforementioned polymers to yield a crimped
structure with the polyamide component situated on the inner sides
of the crimps.
[0081] The woven or knitted fabric which has been dyed is usually
subjected to final dry heat setting. The temperature of the final
dry heat setting is preferably 120 to 200.degree. C. and more
preferably 140 to 180.degree. C., and the time is preferably in the
range of 1 to 3 minutes. If the temperature for the final dry heat
setting is below 120.degree. C., wrinkles created during the dyeing
will tend to remain, and the dimensional stability of the finished
product may be impaired. Conversely, if the temperature for the
final dry heat setting is higher than 200.degree. C., crimping of
the conjugated fibers during dyeing will be reduced and the fibers
may harden and produce a hard feel to the cloth.
[0082] In the woven or knitted fabric obtained in this manner, the
air permeability upon wetting is preferably at least 20% lower than
when dry, and more preferably 30 to 100%. The air permeability is a
property representative of the air space of the woven or knitted
fabric, and a lower air permeability of the woven or knitted fabric
means a smaller air space. The air permeability is the value
(ml/cm.sup.2/s) measured according to JIS L1096 1998, 6.27.1, A
(Fragile-Type Air Permeability Tester Method).
[0083] "Dry" in this case is the state of the sample after standing
for 24 hours in an environment at 20.degree. C., 65% RH, while
"wet" is the state of the sample after immersion for 2 hours in
water at 20.degree. C., sandwiching it between a pair of filter
sheets, subjecting it to a pressure of 490 N/m.sup.2 for one minute
and lightly wiping the water off; the air permeability is measured
for each (n=5) and the average is calculated.
[0084] The woven or knitted fabric of the invention is preferably
subjected to hygroscopic treatment and/or water repellent
treatment, depending on the purpose and intended use. For example,
it is preferably subjected to hygroscopic treatment when the
purpose is improving the anti-visibility property of sportswear and
underwear caused by sweat. Hygroscopic treatment of the woven or
knitted fabric is preferred because it increases the diffusion rate
of sweat and prevents a sticky feel, while also increasing the rate
of change in crimping of the crimped filaments A whose percentage
of crimp decreases upon wetting, and increasing the response speed
for improved anti-visibility. Also, water repellent treatment is
preferred when the purpose is improving the waterproof properties
of windbreakers or ski and snowboard wear in rain. Water repellent
treatment is preferred because it increases the initial
waterproofness while lowering the air space of the woven or knitted
fabric by absorption of moisture and water by the crimped filaments
A whose percentage of crimp decreases upon wetting, during periods
when the water repellent coating of the woven or knitted fabric
surface repels rain, thereby improving the waterproof
properties.
[0085] The agent used for the hygroscopic treatment is preferably
polyethylene glycol or a derivative thereof, or polyethylene
terephthalate-polyethylene glycol copolymer, adhered at 0.25 to
0.50 wt % with respect to the weight of the woven or knitted
fabric. The method for hygroscopic treatment may be, for example, a
bath treatment method in which the hygroscopic agent is mixed with
the dyeing solution during dyeing, or a coating method such as a
method of dipping the woven or knitted fabric in a hygroscopic
treatment solution before the final dry heat setting and squeezing
it with a mangle, a gravure coating method or a screen printing
method.
[0086] On the other hand, the water repellent treatment is
preferably carried out until the water repellency of the woven or
knitted fabric after water repellent treatment is at least level 4
according to JIS L1092 6.2 (Spray Test). An example is a method
wherein a commercially available fluorine-based water repellent
(for example, Asahi Guard LS-317 by Asahi Glass Co., Ltd.) is used
as the water repellent, if necessary with mixture of a melamine
resin and a catalyst, to prepare a treatment agent with a water
repellent agent content of about 3 to 15 wt %, and this treatment
agent is used for treatment of the surface of the fabric at a
pickup rate of about 50 to 90%. The method for treatment of the
surface of the fabric with the water repellent agent may be a pad
method, spray method or the like, but a pad method is most
preferred from the standpoint of penetration of the treatment agent
to the interior of the fabric. The pickup rate is the weight ratio
(%) of the treatment agent with respect to the weight of the fabric
(before applying the treatment agent).
[0087] When a woven or knitted fabric of the invention is wetted by
sweat or rain, the crimped filaments A extend due to reduction in
the amount of their own crimps. Meanwhile, the filaments B do not
extend even when wetted and therefore maintain a fixed dimension of
the woven or knitted fabric, resulting in a lower air space of the
woven or knitted fabric and improved anti-visibility and waterproof
properties of the woven or knitted fabric.
[0088] In addition to the treatments described above, ordinary
methods may be employed to subject the woven or knitted fabric of
the invention to piling treatment, ultraviolet blocking, or various
treatments which confer the functions of antibacterial agents,
deodorants, insecticides, luminous agents, retroreflective agents,
minus ion-generating agents and the like.
[0089] A crimped filament-containing woven or knitted fabric with a
reduced air space upon wetting with water according to the
invention may be used for production of various types of textile
products. Such textile products include outer garments, sportswear,
and underwear.
EXAMPLES
[0090] The present invention will now be explained in greater
detail through the following examples, with the understanding that
the invention is not limited in any way to the examples. The
following measurements were conducted for the examples and
comparative examples.
[0091] (1) Intrinsic Viscosity of Polyester
[0092] This was measured at 35.degree. C. using ortho-chlorophenol
as the solvent.
[0093] (2) Intrinsic Viscosity of Polyamide
[0094] This was measured at 30.degree. C. using m-cresol as the
solvent.
[0095] (3) Tensile Strength and Breaking Elongation
[0096] A fiber sample was allowed to stand a day and a night in a
steady temperature and humidity chamber kept in an atmosphere at
25.degree. C., 60% RH, and then a sample length of 100 mm was set
in a Tensilon tester by Shimadzu Laboratories Co., Ltd. and pulled
at a rate of 200 mm/min, upon which the tensile strength at
breakage (cN/dtex) and the elongation (%) were measured. The
average value of n=5 was calculated.
[0097] (4) Boiling Water Shrinkage
[0098] The boiling water shrinkage (hot water shrinkage) (%) was
measured by the method specified according to JIS L1013 1998, 7.15.
The average value of n=3 was calculated.
[0099] (5) Percentage of Crimp of Conjugated Fiber
[0100] A wind-up frame with a circumference of 1.125 m was used for
rewinding under a load of 49/50 mN.times.9.times.total tex (0.1
gf.times.total denier) at a fixed speed for 10 winds to produce a
small skein, the small skein was twisted into a double ring and
placed in boiling water while subjected to an initial load of
49/2500 mN.times.20.times.9.times.total tex (2
mg.times.20.times.total denier) for 30 minutes of treatment, after
which it was dried for 30 minutes with a drier at 100.degree. C.
and then placed in dry heat at 160.degree. C. while subjected to
the initial load for 5 minutes of treatment. The initial load was
removed after the dry heat treatment, and after standing for at
least 24 hours in an environment at a temperature of 20.degree. C.,
65% RH, the initial load and the 98/50
mN.times.20.times.9.times.total tex (0.2 gf.times.20.times.total
denier) double load were applied, the skein length L0 was measured,
the double load alone was immediately removed, and the skein length
L1 one minute after removing the load was measured. The skein was
then immersed for 2 hours in water at a temperature of 20.degree.
C. while under the initial load, and after removal and lightly
wiping off the water with filter paper, it was subjected to the
initial load and the double load, the skein length L0' was
measured, the double load alone was immediately removed, and the
skein length L1' one minute after removing the load was measured.
These measured values were inserted into the following formula to
calculate the dry percentage of crimp (DC), wet percentage of crimp
(HC) and the difference in dry and wet percentages of crimp
(DC-HC). The average value of n=5 was calculated. Dry percentage of
crimp DC(%)=((L0-L1)/L1).times.100 Wet percentage of crimp
HC(%)=((L0'-L1')/L0').times.100
[0101] (6) Percentage of Crimp of Crimped Conjugated Fibers in
Woven or Knitted Fabric
[0102] The woven or knitted fabric was allowed to stand for 24
hours in an atmosphere at a temperature of 20.degree. C., 65% RH
and then test strips with a length of 30 cm in the warp (or wale)
direction and a width of 30 cm in the weft (or course) direction
were taken from the woven or knitted fabric (n=5). Crimped
filaments A were removed from each of the test strips and subjected
to a load of 1.76 mN/dtex (200 mg/de) and the filament lengths L0f
were measured, and then after 1 minute of releasing the load, a
load of 0.0176 mN/dtex (2 mg/de) was applied and the filament
lengths L1f were measured. Also, the filaments were immersed for 2
hours in water at a temperature of 20.degree. C., removed and then
placed between a pair of filter sheets at a pressure of 0.69
mN/m.sup.2 for 5 seconds and the water was wiped off gently, after
which a load of 1.76 mN/dtex (200 mg/de) was applied, the filament
lengths L0f' were measured, and then after 1 minute of releasing
the load, a load of 0.0176 mN/dtex (2 mg/de) was applied and the
filament lengths L1f' were measured. The measured values were used
in the following formulas to calculate the percentage of crimp when
dry DCf(%), the percentage of crimp when wet HCf(%) and the
difference in percentages of crimp when dry and when wet
(DCf-HCf)(%). The average of n=5 was calculated. Dry percentage of
crimp DCf(%)=((L0f-L1f)/L0f).times.100 Wet percentage of crimp
HCf(%)=((L0f'-L1f')/L0f').times.100
[0103] (7) Air Permeability
[0104] The air permeability was measured by the following method as
a property representing the air space of the woven or knitted
fabric. The air permeability when dry (cc/cm.sup.2/s) and the air
permeability when wet (cc/cm.sup.2/s) were measured for a woven or
knitted fabric sample according to JIS L1096 1998, 6.27.1, A
(Fragile-Type Air Permeability Tester Method). "Dry" was the state
of the sample after standing for 24 hours in an environment at
20.degree. C., 65% RH, while "wet" was the state of the sample
after immersion for 2 hours in water at 20.degree. C., sandwiching
it between a pair of filter sheets, subjecting it to a pressure of
490 N/m.sup.2 for one minute and lightly wiping the water off; the
air permeability was measured for each (n=5) and the average was
calculated. The change in air permeability was calculated by the
following equation. Change in air permeability(%)=((air
permeability when dry)-(air permeability when wet))/(air
permeability when dry).times.100
[0105] (8) Change in Dimensions RA of Sample
[0106] The change in dimensions RA of a sample of the woven or
knitted fabric was calculated in accordance with the following
equations. The average was calculated for n=5. RA(%)=(RP+RF)/2
RP(%)=((LPH-LPD)/LPD).times.100 RF(%)=((LFH-LFD)/LFD).times.100
[0107] Here, LPH, LPD, LFH and LFD respectively represent the
lengths upon wetting with water and the lengths upon drying in the
warp (or wale) direction and the weft (or course) directions of the
sample, where the sample was in a square form with a 30 cm length
in the warp (or wale) direction and a 30 cm width in the weft (or
course) direction from the woven or knitted fabric. LPH: a wet
length of the sample in the warp (or wale) direction (mm), LPD: a
dry length of the sample in the warp (or wale) direction (mm), LFH:
a wet length of the sample in the weft (or course) direction (mm),
LFD: a dry length of the sample in the weft (or course) direction,
"wet": a state of the sample after immersion in water at 20.degree.
C. for 2 hours, immediately sandwiching it between a pair of filter
sheets, subjecting it to a pressure of 0.69 mN/m2 for 5 seconds and
lightly wiping the water off, "dry": a state of the sample after
standing for 24 hours in an environment at 20.degree. C., at 65%
RH.
[0108] (9) Measurement of Yarn Length
[0109] The woven or knitted fabric was allowed to stand for 24
hours in an environment at a temperature of 20.degree. C., 65% RH,
and then a strip of 30 cm (in the warp (or wale)
direction).times.30 cm (in the weft (or course) direction) was cut
out (n=5). Next, a conjugated filament (A) yarn and filament (B)
yarn were taken from each strip, a load of 0.0088 mN/dtex was
applied in the case of an elastic filament or a load of 1.76
mN/dtex in the case of a non-elastic filament, and the length LA of
the conjugated filament A yarn and the length LB of the other
filament B yarn were measured. The average of n=5 was
calculated.
Example 1
[0110] Nylon-6 with an intrinsic viscosity [.eta.] of 1.3 and
modified polyethylene terephthalate copolymerized with 2.6 mole
percent 5-sodiumsulfoisophthalic acid, having an intrinsic
viscosity [.eta.] of 0.39, were melted at 270.degree. C. and
290.degree. C., respectively, and the conjugated fiber spinneret
shown in FIG. 1 of Japanese Unexamined Patent Publication No.
2000-144518 (wherein the spinning hole is a spinning nozzle hole
composed of two arc-shaped slits A and B situated essentially on
the same circumference at a spacing (d), and where the area SA of
the arc-shaped slit A, the slit width A.sub.1, the area SB of the
arc-shaped slit B, the slit width B.sub.1, and the area SC defined
by the inner perimeters of the arc-shaped slits A and B
simultaneously satisfy the following inequalities [1] to [4]:
B.sub.1<A.sub.1 [1] 1.1.ltoreq.SA/SB.ltoreq.1.8 [2]
0.4.ltoreq.(SA+SB)/SC.ltoreq.10.0 [3] d/A.sub.1.ltoreq.3.0) [4] was
used for extrusion of the polyethylene terephthalate from slit A
and the nylon-6 from slit B, at an extrusion rate of 12.7 g/min
each, followed by cooling to solidification and lubricant
application to form a side-by-side undrawn conjugated fiber having
the cross-sectional profile shown in FIG. 1. The filament was
preheated with a preheating roller at a speed of 1000 m/min and a
temperature of 60.degree. C., and then subjected to drawing heat
treatment between the preheating roller and a heating roller heated
to a temperature of 150.degree. C. at a speed of 3050 m/min
(drawing factor: 3.05), and wound up to obtain an 86 dtex/24 fil
uncrimped conjugated fiber.
[0111] The breaking tensile strength of the obtained drawn
conjugated fiber was 3.4 cN/dtex, and the breaking elongation was
40%. When the percentage of crimp was measured after boiling water
treatment of the conjugated fiber, the dry percentage of crimp DC
was 3.3%, the wet percentage of crimp HC was 1.6% and the
difference between the dry percentage of crimp DC and wet
percentage of crimp HC (DC-HC) was 1.7%.
[0112] The conjugated fiber yarns (without boiling water treatment
and without crimping or twisting) were arranged in full set on the
front reed of a 36 gauge tricot knitting machine, while uncrimped
polyethylene terephthalate multifilament yarns (33 dtex/12 fil)
with a boiling water shrinkage of 20% were arranged in full set on
the back reed of the tricot knitting machine, for knitting a tricot
stitched fabric in a knitting structure front 10-23, and back
12-10, with a 110/2.54 cm machine course.
[0113] The tricot stitched fabric was dyed under conditions with a
maximum temperature of 130.degree. C. and a maximum temperature
keep time of 15 minutes, for manifestation of the latent crimping
property of the conjugated fibers, thereby producing a crimped
conjugated fiber yarn-containing tricot knitted fabric; this was
then subjected to padding treatment using a treatment solution
containing 8 wt % of a fluorine resin-based water repellent
(ASAHIGUARD.TM. AG710, product of Asahi Glass Co., Ltd.), and then
dried at a temperature of 100.degree. C. and subjected to final dry
setting at 160.degree. C. for 1 minute.
[0114] The performance of the obtained tricot stitched fabric was
as follows.
LPH: 305 mm
LPD: 300 mm
LFH: 311 mm
RP: 1.7%
RF: 3.7%
RA: 2.7%
Dry air permeability: 14 ml/cm.sup.2/s
Wet air permeability: 10 ml/cm.sup.2/s
Variation in air permeability: 40%
The knitted fabric had a reduced air space upon water wetting and
therefore a lower air permeability, and was therefore
satisfactory.
[0115] The yarn length (LA) of a conjugated fiber yarn (crimped
filament A yarn) taken from the knitted fabric was 2700 mm, and the
yarn length (LB) of a filament B was 1890 mm, and therefore LA was
longer than LB. Also, the dry percentage of crimp DC.sub.f of the
crimped conjugated filament A taken from the knitted fabric was 7%,
the wet percentage of crimp HC.sub.f was 52%, and the dry-wet
percentage of crimp difference (DC.sub.f-HC.sub.f) was 18%.
Comparative Example 1
[0116] The uncrimped conjugated fibers used in Example 1 were
arranged in full set on the front reed and back reed of a 28 gauge
tricot knitting machine, for knitting a tricot stitched fabric in a
knitting structure of front 10-23 and back 12-10, with a 60/2.54 cm
of courses on machine. Dyeing and final dry heat setting were also
carried out on the resultant fabric in the same manner as Example
1.
[0117] The obtained knitted fabric was unsatisfactory, with LPH:
315 mm, LPD: 300 mm, LFH: 330 mm, LFD: 300 mm, RP: 5.0%, RF: 10.0%,
RA: 7.5%, dry air permeability: 140 cc/cm.sup.2/s, wet air
permeability: 250 cc/cm.sup.2/s and air permeability variation:
-79%, i.e. a large increase in air permeability when wet. Also, for
a conjugated fiber taken from the fabric, the dry percentage of
crimp DC.sub.f was 62%, the wet percentage of crimp HC.sub.f was
38% and the difference in the dry and wet percentages of crimp
(DC.sub.f-HC.sub.f) was 22%.
INDUSTRIAL APPLICABILITY
[0118] According to the present invention, it is possible to obtain
woven and knitted fabrics with improved anti-visibility and
waterproof properties by efficient reduction in the air space in a
wet state as compared to a dry state. The woven and knitted fabrics
may be used for outer garments, sportswear and underwear provide
effects of inhibited visibility by sweat and improved
waterproofness in rain, and therefore their industrial value is
very high.
* * * * *