Note: Descriptions are shown in the official language in which they were submitted.
CA 03006539 2018-05-28
MOISTURE-ABSORBING CORE-SHEATH COMPOSITE YARN, AND FABRIC
TECHNICAL FIELD
[0001]
The present invention relates to a hygroscopic core-sheath composite yarn and
fabric.
BACKGROUND ART
[0002]
Synthetic fibers made of thermoplastic resins including polyamide and
polyester are widely
used for clothing and industrial applications because of being high in
strength, chemical
resistance, heat resistance, and the like.
[0003]
In particular, in addition to its unique characteristics including softness,
high tensile strength,
coloring property in dyeing processes, and high heat resistance, polyamide
fiber is so high in
hygroscopicity that it is widely used for applications such as inner wear and
sports wear.
However, polyamide fibers are not sufficiently hygroscopic as compared with
natural fibers
such as cotton and have some problems such as undesired stuffiness and
stickiness,
leading to inferior comfortability to natural fibers.
[0004]
Against this background, synthetic fibers showing excellent moisture absorbing
and
releasing properties for preventing stuffiness and stickiness and having
comfortability similar
to that of natural fibers are now demanded mainly for innerwear and sports
apparel
applications.
[0005]
Then, the addition of a hydrophilic chemical compound to a polyamide fiber has
been
studied most widely. For example, Patent document 1 proposes a method of
improving
hygroscopic performance by blending polyvinylpyrrolidone, used as a
hydrophilic polymer,
with polyamide, followed by spinning.
[0006]
On the other hand, there have been many studies that attempt to produce fibers
having a
core-sheath structure composed mainly of a highly hygroscopic thermoplastic
resin as the
core component and a thermoplastic resin with excellent mechanical properties
as the
sheath component, in an attempt to provide a fiber having both high moisture
absorbing
performance and good mechanical properties.
[0007]
For example, Patent document 2 discloses a core-sheath composite fiber
composed mainly
of a core component and a sheath component in such a manner that the core
component is
not exposed in the fiber surface. In this core-sheath composite fiber, the
core component is a
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=
polyether block amide copolymer containing 6-nylon as a hard segment whereas
the sheath
component is a 6-nylon fiber, wherein the area ratio between the core
component and the
sheath component in the cross section of the fiber is 3/1 to 1/5.
[0008]
Patent document 3 discloses a sheath-core type composite fiber containing a
thermoplastic
resin as the core component and a fiber-forming polyamide resin as the sheath
component,
wherein the main constituent of the thermoplastic resin in the core component
is a polyether
ester amide, the core component accounting for 5% to 50% by weight of the
total weight of
the composite fiber. The document describes a highly hygroscopic core-sheath
type
composite fiber with the above feature containing polyether ester amide as the
core
component and polyamide as the sheath component.
[0009]
In addition, Patent document 4 describes a composite fiber having moisture
absorbing and
releasing properties characterized by containing polyamide or polyester as the
sheath
component and a thermoplastic water absorbing resin made of crosslinked
polyethylene
oxide as the core component. The document mentions a highly hygroscopic core-
sheath
composite fiber containing a highly hygroscopic water-insoluble modified
polyethylene oxide
as the core component and polyamide as the sheath component.
PRIOR ART DOCUMENTS
PATENT DOCUMENTS
[0010]
Patent document 1: Japanese Unexamined Patent Publication (Kokai) No. HEI 09-
188917
Patent document 2: International Publication WO 2014/10709
Patent document 3: Japanese Unexamined Patent Publication (Kokai) No. HEI 06-
136618
Patent document 4: Japanese Unexamined Patent Publication (Kokai) No. HEI 08-
209450
SUMMARY OF THE INVENTION
PROBLEMS TO BE SOLVED BY THE INVENTION
[0011]
However, although having moisture absorbing and releasing properties similar
to those of
natural fibers, the fiber described in Patent document 1 does not have
satisfactorily high
performance, and the achievement of better moisture absorbing and releasing
properties is
still a problem to be solved.
[0012]
In addition, although having moisture absorbing and releasing properties as
good as or
better than those of natural fibers, the core-sheath composite fibers
described in Patent
documents 2 to 4 tend to suffer from thermal degradation of the core component
and
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hardening of the fibers as they undergo frequent washing and drying in
household type
machines, causing the fabrics to suffer from hardening of the texture, a
decrease in durability,
or deterioration in moisture absorbing and releasing performance.
MEANS OF SOLVING THE PROBLEMS
[0013]
The present invention adopts the following constitution to solve the problems
described
above:
[0014]
(1) A hygroscopic core-sheath composite yarn including polyamide as the sheath
polymer
and a polyether ester amide copolymer as the core polymer and characterized by
having a
strength retention rate of 50% or more after undergoing dry heat treatment at
150 C for 1
hour.
[0015]
(2) A hygroscopic core-sheath composite yarn as set forth in paragraph (1)
having a AMR
value of 5.0% or more and a AMR retention rate of 70% or more after undergoing
dry heat
treatment at 150 C for 1 hour.
[0016]
(3) A fabric containing, at least partly, a hygroscopic core-sheath composite
yarn as set forth
in either paragraph (1) or (2).
ADVANTAGEOUS EFFECTS OF THE INVENTION
[0017]
The present invention can provide a core-sheath composite yarn that is high in
hygroscopic
performance, higher in comfortability than natural fibers, and able to
maintain a soft texture,
high durability, and moisture absorbing and releasing performance after
undergoing
repeated washing and drying.
DESCRIPTION OF PREFERRED EMBODIMENTS
[0018]
The core-sheath composite yarn according to the present invention includes
polyamide as
the sheath component and a polyether ester amide copolymer as the core
component.
[0019]
The polyether ester amide copolymer is a block copolymer having an ether bond,
an ester
bond, and an amide bond in one molecular chain. More specifically, the block
copolymer
polymer which can be produced by subjecting one, two, or more selected from
the group
consisting of lactams, aminocarboxylic acids, and salts of diamine and
dicarboxylic acid,
referred to polyamide component (A), and a polyether ester component (B)
formed of a
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dicarboxylic acid and a poly(alkylene oxide) glycol to condensation
polymerization reaction.
[0020]
Substances suitable as the polyamide component (A) include lactams such as
E-caprolactam, dodecanolactam, and undecanolactam; w-aminocarboxylic acids
such as
aminocaproic acid, 11-aminoundecanoic acid, and 12-aminododecanoic acid; and
nylon
salts of diamine-dicarboxylic acids that serve as precursors of nylon 66,
nylon 610, nylon
612, etc., of which E-caprolactam is preferred as polyamide-forming component.
[0021]
The polyether ester component (B) is formed of a dicarboxylic acid containing
4 to 20 carbon
atoms and a poly(alkylene oxide) glycol. Examples of the dicarboxylic acid
containing 4 to 20
carbon atoms include aliphatic dicarboxylic acids such as succinic acid,
glutaric acid, adipic
acid, pimelic acid, suberic acid, sebacic acid, and dodecanoic acid; aromatic
dicarboxylic
acids such as terephthalic acid, isophthalic acid, and 2,6-naphthalene
dicarboxylic acid; and
alicyclic dicarboxylic acids such as 1,4-cyclohexanedicarboxylic acid, which
may be used
singly or as a mixture of two or more thereof. Preferable dicarboxylic acids
include adipic
acid, sebacic acid, dodecanoic acid, terephthalic acid, and isophthalic acid.
Examples of the
poly(alkylene oxide) glycol include polyethylene glycol, poly(1,2- or 1,3-
propylene oxide)
glycol, poly(tetramethylene oxide) glycol, and poly(hexamethylene oxide)
glycol, of which
polyethylene glycol is preferable because of having high hygroscopic
performance.
[0022]
It is preferable for the poly(alkylene oxide) glycol to have a number average
molecular
weight of 300 to 3,000, more preferably 500 to 2,000. A molecular weight of
300 or more is
preferable because scattering out of the system during condensation
polymerization
reaction can be prevented to ensure the formation of a fiber with stable
hygroscopic
performance. A molecular weight of 3,000 or less is preferable because the
poly(alkylene
oxide) glycol can be dispersed uniformly in the polymer to ensure high
hygroscopic
performance.
[0023]
Regarding the component percentage of the polyether ester component (B), it
preferably
accounts for 20% to 80% by mole of the total quantity of the polyether ester
amide
copolymer. A percentage of 20% or more is preferable because high hygroscopic
performance can be realized. On the other hand, a percentage of 80% or less is
preferable
to ensure high dyed color fastness and little hygroscopic performance
deterioration by
washing.
[0024]
The component percentages of the polyamide and poly(alkylene oxide) glycol are
preferably
20%/80% to 80%/20% by mole. A poly(alkylene oxide) glycol content of 20% or
more is
preferable because high hygroscopic performance can be realized. On the other
hand, a
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poly(alkylene oxide) glycol preferably content of 80% or less is preferable to
ensure high
dyed color fastness and little hygroscopic performance deterioration by
washing.
[0025]
Commercially available products of such a polyether ester amide copolymer
include
MH1657 and MV1074 manufactured by Arkema K.K.
[0026]
Examples of the polyamide used as the sheath component include nylon 6, nylon
66, nylon
46, nylon 9, nylon 610, nylon 11, nylon 12, and nylon 612; and copolymer
polyamides
containing, as a copolymer component, a compound having a functional group
that can form
an amide with the former, such as laurolactam, sebacic acid, terephthalic
acid, isophthalic
acid, and 5-sodium sulfoisophthalic acid. In particular, nylon 6, nylon 11,
nylon 12, nylon 610,
and nylon 612 are preferable from the viewpoint of yarn-making performance
because they
are small in the difference in melting point from the polyether ester amide
copolymer, serving
to depress the thermal degradation of the polyether ester amide copolymer
during melting
spinning. Of these, nylon 6 is particularly preferable because of high
dyeability.
[0027]
It is essential for the core-sheath composite yarn according to the present
invention to have
a strength retention rate of 50% or more and 100% or less after undergoing dry
heat
treatment at 150 C for 1 hour. If it is less than 50%, the raw threads will
become hard and
brittle and a fabric test piece will decrease in durability and suffer
breakage etc. when
subjected to repeated drying test in a household washing and drying machine
(hereinafter
referred to as tumble drying). It is preferably 60% or more and 100% or less.
If it is in this
range, it will be possible to produce clothing that can maintain durability
after repeated
tumble drying.
[0028]
It is preferable for the core-sheath composite yarn according to the present
invention to have
a tensile strength of 2.5 cN/dtex or more. It is more preferably 3.0 cN/dtex
or more. If it is in
this range, it will be possible to produce clothing that are high enough in
strength to serve for
practical clothing uses such as innerwear and sports apparel applications.
[0029]
It is essential for the core-sheath composite yarn according to the present
invention to have
a function to maintain controlled humidity in clothing to ensure high
comfortability when they
are worn. The degree of humidity control is examined based on AMR, which
denotes the
difference between the hygroscopicity at 30 C and 90% RH, which represent a
typical
temperature and humidity conditions in clothing resulting from a light to
medium degree of
work or a light to medium degree of exercise and that at 20 C and 65% RH,
which represent
a typical outdoor air temperature and humidity conditions. A larger AMR value
ensures a
higher hygroscopic performance and higher comfortability when the clothes are
worn.
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[0030]
It is preferable for the core-sheath composite yarn according to the present
invention to have
a AMR value of 5.0% or more. It is more preferably 7.0% or more and still more
preferably
10.0% or more. If it is in this range, it will be possible to produce clothing
that have reduced
stuffiness and stickiness when worn and have high comfortability.
[0031]
It is preferable for the core-sheath composite yarn according to the present
invention to have
a AMR retention rate of 70% or more and 100% or less after undergoing dry heat
treatment
at 150 C for 1 hour. If it is in this range, it will be possible to produce
clothing that can
maintain moisture absorbing and releasing performance as well as high
comfortability after
undergoing repeated tumble drying.
[0032]
A polyether ester amide copolymer to be used in the core for the present
invention contains
both a hindered phenolic stabilizer, which is an antioxidant to capture
radicals, and a
hindered amine based stabilizer (hereinafter referred to as HALS type
stabilizer) to make it
possible to provide a core-sheath composite yarn characterized by depressed
thermal
degradation of the polyether ester amide copolymer even after undergoing
repeated tumble
drying to ensure a high durability and moisture absorbing and releasing
performance as well
as a soft texture.
[0033]
The polyether ester amide copolymer used in the core contains poly(alkylene
oxide) glycol,
and when the poly(alkylene oxide) glycol is heated, radicals will be generated
from the
molecule and attack adjacent atoms to further generate radicals to cause chain
reaction, and
the reaction heat will work to increase the temperature up to as high as 200
C. As the
molecular weight of the poly(alkylene oxide) glycol decreases, the molecular
chain will be
heated more easily to generate more radicals and generate more reaction heat.
[0034]
The polyether ester amide copolymer used for the present invention contains a
poly(alkylene
oxide) glycol having a relatively low number average molecular weight of 300
to 3,000 and
accordingly, the polyether ester amide copolymer tends to undergo thermal
degradation
easily through the above mechanism, thus leading very easily to raw threads
that are hard
and brittle and have an inferior hygroscopic performance.
[0035]
To avoid this, a hindered phenolic stabilizer, which is an antioxidant to
capture radicals, is
added to the polyether ester amide copolymer contained in the core. However,
the addition
of a hindered phenolic stabilizer alone will lead to progress of thermal
degradation of the
polyether ester amide copolymer due to the heat history in the spinning step
(high
temperature heating for melting the polymer and thermal setting after
stretching) and the
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heat history in high-order processing steps (dyeing, thermal setting, etc. of
fabric), resulting
in a large decrease in the effective component quantity of the antioxidant
working to capture
radicals remaining at the stages of fabrics and clothing. As they subsequently
undergo
repeated tumble drying, the polyether ester amide copolymer will suffer from
further thermal
degradation and the raw threads will become harder and more brittle and
deteriorate in
hygroscopic performance. Thus, the texture will become harder due to repeated
washing
and drying, leading to deterioration in durability and moisture absorbing and
releasing
performance.
[0036]
Therefore, if a HALS (hindered amine light stabilizer) type stabilizer is used
in combination to
prevent a decrease in the effective component quantity of the antioxidant that
works to
capture radicals remaining in fabrics or clothing products, thermal
degradation of the
hindered phenolic stabilizer will be depressed to allow a soft texture, high
durability, and
moisture absorbing and releasing performance to be maintained after repeated
tumble
drying.
[0037]
Regarding the quantity of the hindered phenolic stabilizer to be added when
producing the
core-sheath composite yarn according to the present invention, it preferably
accounts for 1.0
wt% or more and 5.0 wt% or less relative to the weight of the polyether ester
amide
copolymer in the core. It more preferably accounts for 2 wt% or more and 4 wt%
or less. If it
is 1.0 wt% or more, it will be possible to produce raw threads that will not
become hard or
brittle or deteriorate in hygroscopic performance after undergoing repeated
tumble drying. If
it is 5.0 wt% or less, the yarn-making performance will be high and yellowing
of the raw
threads will be reduced.
[0038]
The quantity of the residual hindered phenolic stabilizer in the core-sheath
composite yarn is
preferably 70% or more of the quantity of the hindered phenolic stabilizer
(relative to the
core-sheath composite yarn) added in the production process. It is more
preferably 80% or
more. If it is in this range, it will be possible to produce raw threads that
will not become hard
or brittle or deteriorate in hygroscopic performance after undergoing repeated
tumble drying.
[0039]
Regarding the quantity of the HALS type stabilizer to be added when producing
the
core-sheath composite yarn according to the present invention, it preferably
accounts for 1.0
wt% or more and 5.0 wt% or less relative to the weight of the polyether ester
amide
copolymer in the core. It more preferably accounts for 1.5 wt% or more and 4.0
wt% or less.
If it is 1.0 wt% or more, it will be possible to depress the thermal
degradation of the hindered
phenolic stabilizer used in combination. If it is 5.0 wt% or less, the yarn-
making performance
will be high and yellowing of raw threads will be reduced.
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,
[0040]
For the hindered phenolic stabilizer and HALS type stabilizer used for the
present invention,
the 5% weight loss temperature during thermogravimetric analysis is preferably
300 C or
more. If it is 300 C or more, the stabilizer itself will suffer little
degradation that may be
caused by the heat history in the spinning step or the heat history in high-
order processing
steps to allow a significant effective component quantity of the antioxidant
to be left to
capture radicals remaining in fabric and clothing products so that the
polyether ester amide
copolymer will suffer little thermal degradation after undergoing repeated
tumble drying and
serve to maintain a soft texture and high durability and moisture absorbing
and releasing
performance, and therefore it is preferable.
[0041]
Examples of such a hindered phenolic stabilizer used for the present invention
include, for
example, pentaerythritoltetrakis [3-(3,5-di-tert-butyl-4-hydroxyphenyl)
propionate] (IR1010),
(1,3, 5-trimethy1-2 ,4 ,6-tris-(3, 5-d i-tert-butyl-4-hyd roxyphenyl)
benzene (A0-330),
1,3,5-tris4[3,5-bis(1,1-dimethylethyl)-4-hydroxyphenyl]
methyl]-1,3,5-triazine-2,4,6(1H,3H,5H)-trione (IR3114), and
N,N'-hexamethylene
bis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propane amide] (I R1098).
[0042]
Examples of such a HALS type stabilizer used for the present invention
include, for example,
a polycondensate of
dibutylamine-1,3,5-triazine,
N,N-bis(2,2,6,6-tetramethy1-4-piperidy1-1,6-hexamethylene diamine,
and
N-(2,2,6,6-tetramethy1-4-piperidyl)butyl amine (CHIMASSORB2020FDL), 4,7,N,N'-
tetrakis
[4,6-bis[buty1(1,2,2,6,6-pentamethy1-4-piperidinyl)amino]-1,3,5-triazine-2-y1]-
4,7-diazadecan
e-1,10-diamine (CHIMASSORB119),
poly[{6-(1,1,3.3-tetramethylbutyl)
amino-1,3,5-triazine-2,4-diy1) ((2,2,6,6-tetramethy1-4-piperidyl)imino)
hexamethylene
((2,2,6,6-tetramethy1-4-piperidyl) imino (CHIMASSORB944).
[0043]
The polyamide sheath component for the present invention may contain, in the
form of a
copolymer or a mixture, various additives such as, for example, delustering
agent, flame
retardant, ultraviolet absorber, infrared ray absorbent, crystal nucleating
agent, fluorescent
whitening agent, antistatic agent, hygroscopic polymer, and carbon, as
required in such a
manner that the total additive content is in the range of 0.001% to 10 wt% of
the total fiber
quantity.
[0044]
It is preferable for the core-sheath composite yarn according to the present
invention to have
an elongation percentage of 35% or more. It is more preferably 40% to 80%. If
it is in this
range, a high process passability will be ensured for high-order steps such as
weaving,
knitting, and false-twisting.
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[0045]
There are no specific limitations on the total fineness and number of
filaments in the
core-sheath composite yarn according to the present invention, and the
resulting fabrics
may have any desired cross-sectional shape to meet their purposes. In view of
its use as
long fiber material for clothing, multifilaments produced therefrom preferably
have a total
fineness of 5 decitex or more and 235 decitex or less and contain 1 or more
and 144 or less
filaments. The cross section may preferably be circular, triangle, flattened,
Y-shaped,
start-like, eccentric, or pasted type.
[0046]
The core-sheath composite yarn according to the present invention can be
produced by a
generally known method such as melt-spinning and composite spinning, and
typical
methods are described below.
[0047]
For example, polyamide (the sheath component) and a polyether ester amide
copolymer
(the core) are melted, weighed, and transported by a gear pump separately, and
then they
are combined by a common method into a composite flow having a core-sheath
structure
and discharged from a spinneret to produce threads, which are then cooled to
room
temperature by applying cooling air from a cooling apparatus such as chimney,
bundled
while supplying oil from an oil feeding apparatus, interlaced by a first fluid
interlacing nozzle
apparatus, and transported on a take-up roller and a stretching roller where
the yarn is
stretched according to the ratio of circumferential speeds of the take-up
roller and the
stretching roller. Subsequently, the yarn is heat-set by the heat of the
stretching roller and
wound up by a winder (winding-up apparatus).
[0048]
In the spinning step, it is preferable for the spinning temperature to be 240
C or more and
270 C or less. A spinning temperature of 240 C or more is preferable because
the
polyamide and polyether ester amide copolymer will have a melt viscosity
suitable for
melt-spinning. A temperature of 270 C or less is preferable because the
hindered phenolic
stabilizer and the HALS type stabilizer can be performed effectively without
undergoing
thermal decomposition, thus serving to depress the thermal decomposition of
the polyether
ester amide copolymer.
[0049]
For the core-sheath composite yarn according to the present invention, it is
necessary for
the core to account for 20 wt% to 80 wt% of the entire composite yarn. It is
more preferably
30 wt% to 70 wt%. If it is in this range, it will be possible to stretch the
polyamide in the
sheath to an appropriate degree. It will be also possible to achieve a desired
dyed color
fastness and hygroscopic performance. If it is less than 20 wt%, a sufficient
hygroscopic
performance may not be achieved. If it is more than 80 wt%, on the other hand,
cracking of
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the fiber surface may occur easily due to swelling in a hydrothermal
atmosphere such as in
the dyeing step, and in addition the polyamide in the sheath may be stretched
excessively to
cause thread breakage and fuzzing. For stable production of intended fibers,
spinning and
stretching that can cause excessive tension are not desirable because thread
breakage and
fuzzing may be caused.
[0050]
The sheath of the present invention is preferably formed of polyamide chips
having a sulfuric
acid relative viscosity of 2.3 or more and 3.3 or less. If it is in this
range, it will be possible to
stretch the polyamide in the sheath to an appropriate degree.
[0051]
For the present invention, the polymer chips of the polyether ester amide
copolymer used in
the core preferably has an orthochlorophenol relative viscosity of 1.2 or more
and 2.0 or less.
An orthochlorophenol relative viscosity of 1.2 or more is preferable because
an optimum
stress will be applied to the sheath during spinning and accordingly, the
crystallization of the
polyamide in the sheath will be accelerated to ensure high strength.
[0052]
Good methods for blending a hindered phenolic stabilizer or a HALS type
stabilizer with a
polyether ester amide copolymer include the dry blending method in which a
hindered
phenolic stabilizer or a HALS type stabilizer is attached to chips of a
polyether ester amide
copolymer and the master chip method in which master chips of a polyether
ester amide
copolymer mixed with a high concentration of a hindered phenolic stabilizer or
HALS type
stabilizer are prepared first in a twin screw extruder or a single screw
extruder, followed by
blending the master chips and polyether ester amide copolymer chips in the
spinning step.
Use of the master chips is preferable because a high concentration of a
hindered phenolic
stabilizer or HALS type stabilizer can be dispersed uniformly in the polymer.
'
[0053]
The spinning conditions are preferably set up so that the speed of the threads
taken up on
the take-up roller (spinning speed) multiplied by the draw ratio, which is the
-ratio in
circumferential speed between the take-up roller and the stretching roller, is
3,300 or more
and 4,500 or less in the stretching step. It is more preferably 3,300 or more
and 4,000 or less.
This value represents the total quantity of stretching that the polymer
undergoes as it is
discharged from the spinneret, accelerated from the spinneret discharging
linear speed to
the circumferential speed of the take-up roller, and pulled further from the
circumferential
speed of the take-up roller to the circumferential speed of the stretching
roller. If it is in this
range, it will be possible to stretch the polyamide in the sheath to an
appropriate degree. A
value of 3,300 or more is preferable because it ensures accelerated
crystallization of the
polyamide in the sheath, leading to an improved raw thread strength and heat
resistance. A
value of 4,500 or less is preferable because it ensures moderate
crystallization of the
CA 03006539 2018-05-28
polyamide in the sheath, leading to a lower degree of thread breakage and
fuzzing in the
yarn-making step.
[0054]
The thermal setting temperature on the stretching roller is preferably 110 C
or more and
160 C or less. A temperature of 110 C or more is preferable because it ensures
accelerated
crystallization of the nylon in the sheath, leading to improvement in strength
and depression
of tight winding by the drum. A temperature of 160 C or less is preferable
because it ensures
depression of the thermal decomposition of the hindered phenolic stabilizer.
[0055]
For the oil feeding step, the spinning oil solution fed by the oil feeding
apparatus is
preferably a non-aqueous oil solution. The polyether ester amide copolymer in
the core is a
highly hygroscopic polymer with a AMR value of 10% or more, and accordingly,
the use of a
non-aqueous oil solution is preferable because it allows gradual absorption of
moisture from
air, thus preventing significant swelling to ensure stable winding-up.
[0056]
The core-sheath composite yarn according to the present invention shows high
hygroscopic
performance and accordingly, it is preferred for production of clothing. The
intended fabric
may be in the form of woven fabric, knitted fabric, nonwoven fabric, etc., as
required to meet
particular purposes. As described above, a larger AMR value ensures a higher
hygroscopic
performance and higher comfortability when the fabric is worn. In the case of
a fabric at least
partly containing the core-sheath composite yarn according to the present
invention,
therefore, clothing with high comfortability can be produced by controlling
the mixing rate of
the core-sheath composite yarn according to the present invention so as to
adjust the AMR
value to 5.0% or more. Examples of such clothing include innerwear,
sportswear, and other
various clothing products.
EXAMPLES
[0057]
The present invention is now described in more detail with reference to
examples. The
methods used for the measurement of characteristic values are as described
below.
[0058]
(1) Sulfuric acid relative viscosity
First, 0.25 g of a specimen was dissolved in sulfuric acid with a
concentration of 98 wt% in
such a manner that it would account for 1 g in 100 ml, and the efflux time
(Ti) through an
Ostwald type viscometer was measured at 25 C. Subsequently, the efflux time
(T2) of the
sulfuric acid with a concentration of 98 wt% alone was measured. The ratio of
Ti to T2 , i.e.,
T1/1-2, was adopted as sulfuric acid relative viscosity.
[0059]
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(2) Orthochlorophenol relative viscosity
First, 0.5 g of a specimen was dissolved in orthochlorophenol in such a manner
that it would
account for 1 g in 100 ml, and the efflux time (Ti) through an Ostwald type
viscometer was
measured at 25 C. Subsequently, the efflux time (T2) of the orthochlorophenol
alone was
measured. The ratio of T1 to T2, i.e., T1/T2, was adopted as sulfuric acid
relative viscosity.
[0060]
(3) Fineness
A fiber specimen was set on a sizing reel with a circumference of 1.125 m and
rotated 200
times to prepare a loop like hank, and then the hank was dried in a hot air
drier (105 2 C for
60 minutes) and weighed in a balance, followed by multiplying the weight by an
official
moisture regain to calculate the fineness. The official moisture regain of the
core-sheath
composite yarn was assumed to be 4.5%.
[0061]
(4) Strength and elongation percentage
A fiber specimen was subjected to measurement using TENSILON (registered
trademark)
UCT-100 manufactured by Orientec Co., Ltd. under the constant stretching rate
conditions
specified in JIS L1013 (Chemical fiber filament test method, 2010). The
elongation
percentage was determined from the elongation at the maximum strength point on
the
tensile strength vs. elongation curve. The strength is calculated by dividing
the maximum
strength by the fineness. For strength and elongation percentage, ten
measurements were
taken and their average was adopted.
[0062]
(5) Strength after dry heat treatment
A fiber specimen was set on a sizing reel with a circumference of 1.125 m and
rotated 200
times to prepare a loop like hank, and then the hank was heat-treated in a hot
air drier
(150 2 C for 60 minutes), followed by calculating the strength of the dry-heat-
treated
specimen as described in paragraph (4).
[0063]
(6) Strength retention rate after dry heat treatment
To represent the difference in strength between before and after the dry heat
treatment, the
strength retention rate of a heat-treated specimen was calculated by the
equation given
blow:
(strength after dry heat treatment! strength before dry heat treatment) x 100.
[0064]
(7) 5% weight loss temperature
A thermogravimetric analyzer (TGA7, manufactured by Perkin Elmer) was used for
the
measurement. In a nitrogen atmosphere, a 10 mg specimen was heated from 30 C
to 400 C
at a heating rate of 10 C/min, followed by calculating the temperature at the
point of 5%
12
CA 03006539 2018-05-28
weight reduction.
[0065]
(8) Quantity of residual hindered phenolic stabilizer (relative to core-sheath
composite yarn)
A. Preparation of standard solution
In a 20 mL measuring flask, 0.02 g of a hindered phenolic stabilizer was
weighed out and 2
mL of chloroform was added to dissolve it, followed by adding tetrahydrofuran
(THE) to
volume (undiluted standard solution: about 1,000 pg/mL). The original standard
solution was
diluted appropriately with acetonitrile to prepare a standard solution.
[0066]
B. Preparation of additive standard solution
In a 10 mL measuring flask, 0.01 g of a hindered phenolic stabilizer was
weighed out and 2
mL of chloroform was added to dissolve it, followed by adding tetrahydrofuran
(THE) to
volume (standard solution for adding hindered phenolic stabilizer: about 1,000
pg/mL).
[0067]
C. Preparation of specimen solution (n=2)
a. A 0.1 g portion of a fiber specimen was dissolved in 1 mL of
hexafluoroisopropanol (HFIP)
and 2 mL of chloroform was added and dissolved.
b. A 40 mL volume of tetrahydrofuran (THE) was added gradually (the polymer
was
insolubilized).
c. Filtration was performed through a paper filter and the solution obtained
was condensed
and exsiccated.
d. A 1 mL volume of HFIP was added to the residue to dissolve it and the
resulting solution
was transferred to a 10 mL measuring flask.
e. The container used above was washed with THE and the washings were added to
10 mL.
f. Filtration was performed through a PTFE membrane filter with a pore size of
0.45 pm and
the resulting solution was adopted as specimen solution.
Pre-treatment was performed without using a specimen to provide a blank test
solution.
[0068]
D. LC/UV and LC/ELSD analysis conditions
LC system: [Cl GA (manufactured by Shimadzu Corporation)
Column: Asahipak ODP-40 4D 4.6 x 150 mm, 4 pm (manufactured by Showa Denko
K.K.)
Mobile phase: A - [28% aqueous ammonia / methanol = 9/1,000] / water = 1/1
B - 0.1% triethyl amine THE solution
Time program
0 to 3 min B:50%
3 to 10 min B: 50% --> 70%
to 15 min B: 70% --> 90%
to 20 min B: 90% --> 100%
13
CA 03006539 2018-05-28
Flow rate: 1.0 mL/min
Injection rate: 20 pL
Column temperature: 45 C
Detection: hindered phenolic stabilizer UV 280 nm
[0069]
(9) Preparation of cylindrical knitted fabric
A cylindrical knitted fabric sample was produced using a cylindrical knitting
machine while
adjusting the density to 50. If the fiber is low in the corrected weight based
fineness, yarn
doubling is performed appropriately so that the fiber fed to the cylindrical
knitting machine
would have a total fineness of 50 to 100 decitex. If the total fineness is
more than 100
decitex, a single yarn was fed to the cylindrical knitting machine and the
density was
adjusted to 50 as in the above case.
[0070]
(10) AMR
About 1 to 2 g of the cylindrical knitted fabric was weighed out in a weighing
bottle, dried by
storage at 110 C for 2 hours, and weighed (WO). Subsequently, the target
substance was
maintained at 20 C and a relative humidity of 65% for 24 hours and then
weighed (W65).
This was maintained at 30 C and a relative humidity of 90% for 24 hours and
then weighed
(W90). Calculations were made by the equations given below.
[0071]
MR65 = [(W65-W0) / WO] x 100% (1)
MR90 = [(W90-W0) /WO] x 100% (2)
AMR = MR90 - MR65 (3)
[0072]
(11) AMR after dry heat treatment
The cylindrical knitted fabric sample was heat-treated (150 2 C for 60
minutes) in a hot air
drier and then its moisture absorbing and releasing properties were measured,
followed by
making calculations.
[0073]
(12) AMR retention rate after dry heat treatment
To represent the difference in AMR between before and after the dry heat
treatment, the
AMR retention rate of a dry-heat-treated specimen was calculated by the
equation given
below:
(AMR after dry heat treatment /AMR before dry heat treatment) x 100.
[0074]
(13) Tumble drying
The cylindrical knitted fabric sample was dried at a temperature of 80 C for 1
hour in a
type-Al tumble drying machine as specified in JIS L1930 (2014, household
washing test
14
CA 03006539 2018-05-28
method) Appendix G. This procedure was repeated 10 times.
[0075]
(14) Texture evaluation
The texture of the tumble-dried cylindrical knitted fabric sample was
evaluated according to
the four stage criterion given below. A specimen rated as A or higher was
assumed to be
acceptable.
S: The texture is just as soft as before tumble drying.
A: The texture is nearly as soft as before tumble drying.
B: The texture is a little harder than before tumble drying.
C: The texture is significantly harder and stiffer than before tumble drying.
[0076]
(15) Durability evaluation
The durability of a tumble-dried cylindrical knitted fabric sample was
evaluated according to
Method A (Muhlen type method) specified in "8.18 Bursting strength" of JIS
L1096 (2010,
Fabric test method for woven fabrics and knitted fabrics). A specimen rated as
A or higher
was assumed to be acceptable.
S: 200 kPa or more
A: 150 kPa or more and less than 200 kPa
C: less than 150 kPa.
[0077]
(16) Hygroscopicity retention property
The value of AMR, which is defined in paragraph (10), of a cylindrical knitted
fabric sample
was measured before and after tumble drying, followed by calculating the
retention rate. A
sample rated as A or higher was assumed to be acceptable.
S: 80% or more
A: 70% or more and less than 80%
C: less than 70%
[0078]
[Example 1]
A polyether ester amide copolymer containing nylon 6 as polyamide component
and
polyethylene glycol with a molecular weight of 1,500 as polyether component
with a molar
ratio of 24% to 76% between nylon 6 and polyethylene glycol (MH1657,
manufactured by
Arkema K.K., orthochlorophenol relative viscosity 1.69) was adopted, and chips
of the
polyether ester amide copolymer were used as core material. First, master
chips prepared
by adding a hindered phenolic stabilizer (IR1010, manufactured by BASF, 5%
weight loss
temperature 351 C) and a HALS type stabilizer (CHIMASSORB2020FDL, manufactured
by
BASF, 5% weight loss temperature 404 C) to high concentrations to the
polyether ester
amide copolymer and chips of the polyether ester amide copolymer were blended
in a twin
CA 03006539 2018-05-28
screw extruder so that the hindered phenolic stabilizer (IR1010) and HALS type
stabilizer
(CHIMASSORB2020FDL) would account for 2.0 wt%/2.0 wt%, respectively, of the
core.
[0079]
As the polyamide component, chips of nylon 6 with a sulfuric acid relative
viscosity of 2.71
were used in the sheath.
[0080]
The polyether ester amide copolymer adopted as core component and the nylon 6
adopted
as sheath component were melted at a spinning temperature of 260 C and spun
through a
spinneret designed for concentric circular core-sheath composite yarn at a
core/sheath ratio
(wt%) of 30/70. Here, the rotating speed of the gear pump was controlled so as
to produce a
core-sheath composite yarn having a total fineness of 56 dtex and the threads
were cooled
and solidified in a thread cooling apparatus, fed with oil from a non-aqueous
oil solution
feeding apparatus, interlaced in a first fluid interlacing nozzle apparatus,
stretched by a
take-up roller (first roller) having a circumferential speed of 2,405 m/min
and a stretching
roller (second roller) having a circumferential speed of 3,608 m/min,
thermally set by the
stretching roller at 150 C, and wound up at a speed of 3,500 m/min to provide
a 56-decitex,
24-filament core-sheath composite yarn. Physical properties of the resulting
fiber are shown
in Table 1.
[0081]
For the resulting core-sheath composite yarn, the proportion of the residual
hindered
phenolic stabilizer was 88%, and the strength retention rate after dry heat
treatment and the
AMR retention rate after dry heat treatment were 65% and 75%, respectively.
After
undergoing repeated tumble drying, the raw threads in the resulting core-
sheath composite
yarn hardly became hard or brittle and maintained a soft texture and a high
durability and
moisture absorbing and releasing performance.
[0082]
[Example 2]
Except for adjusting the spinning temperature to 270 C, the same procedure as
in Example
1 was carried out to provide a 56-decitex, 24-filament core-sheath composite
yarn. Physical
properties of the resulting fiber are shown in Table 1.
[0083]
For the resulting core-sheath composite yarn, the proportion of the residual
hindered
phenolic stabilizer was 75%, and the strength retention rate after dry heat
treatment and the
AMR retention rate after dry heat treatment were 60% and 72%, respectively.
[0084]
[Example 3]
Except for adjusting the spinning temperature to 240 C, the same procedure as
in Example
1 was carried out to provide a 56-decitex, 24-filament core-sheath composite
yarn. Physical
16
CA 03006539 2018-05-28
properties of the resulting fiber are shown in Table 1.
[0085]
The proportion of the residual hindered phenolic stabilizer in the resulting
core-sheath
composite yarn was a high 93%, and the strength retention rate after heat
treatment and the
AMR retention rate after heat treatment were high 70% and 77%, respectively.
[0086]
[Example 4]
Except for adjusting the stretching roller temperature to 120 C, the same
procedure as in
Example 1 was carried out to provide a 56-decitex, 24-filament core-sheath
composite yarn.
Physical properties of the resulting fiber are shown in Table 1.
[0087]
The proportion of the residual hindered phenolic stabilizer in the resulting
core-sheath
composite yarn was a high 90%, and the strength retention rate after heat
treatment and the
AMR retention rate after heat treatment were high 67% and 77%, respectively.
[0088]
[Example 5]
Except for performing the spinning at a core/sheath ratio of 50/50 (parts by
weight), the
same procedure as in Example 1 was carried out to provide a 56-decitex, 24-
filament
core-sheath composite yarn. Physical properties of the resulting fiber are
shown in Table 1.
[0089]
The proportion of the residual hindered phenolic stabilizer in the resulting
core-sheath
composite yarn was a high 85%, and the strength retention rate after heat
treatment and the
AMR retention rate after heat treatment were high 63% and 72%, respectively.
[0090]
[Table 1]
17
[Table 1]
Example 1 Example 2
Example 3 Example 4 Example 5
polymer
polyether ester polyether ester
polyether ester polyether ester polyether ester .
Core component amide copolymer amide copolymer
amide copolymer amide copolymer amide copolymer
relative viscosity 1.69 1.69
1.69 1.69 1.69
Sheath component polymer nylon 6 nylon 6
nylon 6 nylon 6 nylon 6
relative viscosity 2.71 2.71
2.71 2.71 2.71
___
Core-sheath ratio core/sheath 30/70 30/70
30/70_ 30/70 50/50
Hindered phenolic
type IR1010 IR1010
IR1010 IR1010 IR1010
-
stabilizer content (wt%) 2.00 2.00
2.00 2.00 2.00
5% weight loss temperature (T) 351 351
351 351 351
CHIMASSROB - CHIMASSROB
CHIMASSROB CHIMASSROB CHIMASSROB
type
2020FDL 2020FDL
2020FDL 2020FDL 2020FDL
HALS type stabilizer -
content (wt%) 2.00 2.00
2.00 2.00 2.00
5% weight loss temperature ( C) 404 404
404 404 404
spinning temperature ( C) 260_ 270
240 260 260
take-up speed (m/min) 2405_ 2405
2405 2405 2405
Yarn-making conditions draw ratio 1.5_ 1.5
1.5 1.5 1.5
product 3608_ 3608
3608 3608 3608
thermal setting temperature ( C) 150_ 150
150 120 150
fineness (dtex) 56____ 56
56 56 56 Q
Physical properties of elongation percentage (/0) 50
50 50 50 48 0
,
_______________________________________________________________________________
_______________________________________________ .
raw thread proportion of residual hindered
0
88 75
93 90 85 .
u,
phenolic stabilizer (%)
_
.
strength (cN/dtex) 3.5 3.6
3.3 3.3 3.2
_
.
strength after
. __ ,
0
Strength retention 2.3 2.2
2.3 2.2 2.0 ,
heat treatment (cN/dtex)
u,
retention rate (%) 65 60
70 67 63 ,
r.,
0
AMR(%) 7.5 7.2
7.7 7.5 11.7
Hygroscopic AMR after
5.6 5.2
5.9 5.8 8.4
performance retention heat treatment (%)
retention rate (%) 75 72
77 77 72
_
Evaluation of cylindrical texture A A
S A A
knitted fabric after durability S S
S S S
tumble drying hygroscopicity retention A A
A A A
18
CA 03006539 2018-05-28
[0091]
[Example 6]
Except for performing the spinning step at a core/sheath ratio of 70/30 (parts
by weight), the
same procedure as in Example 1 was carried out to provide a 56-decitex, 24-
filament
core-sheath composite yarn. Physical properties of the resulting fiber are
shown in Table 2.
[0092]
The proportion of the residual hindered phenolic stabilizer in the resulting
core-sheath
composite yarn was a high 83%, and the strength retention rate after heat
treatment and the
AMR retention rate after heat treatment were high 60% and 70%, respectively.
[0093]
[Example 7]
Except for adjusting the hindered phenolic stabilizer (IR1010) and HALS type
stabilizer
(CHIMASSORB2020FDL) to 3.0 wt% and 2.0 wt%, respectively, relative to the
weight of the
core, the same procedure as in Example 1 was carried out to provide a 56-
decitex,
24-filament core-sheath composite yarn. Physical properties of the resulting
fiber are shown
in Table 2.
[0094]
The proportion of the residual hindered phenolic stabilizer in the resulting
core-sheath
composite yarn was a high 86%, and the strength retention rate after heat
treatment and the
AMR retention rate after heat treatment were high 70% and 78%, respectively.
[0095]
[Example 8]
Except for adjusting the hindered phenolic stabilizer (IR1010) and HALS type
stabilizer
(CHIMASSORB2020FDL) to 3.0 wt% and 3 wt%, respectively, relative to the weight
of the
core, the same procedure as in Example 1 was carried out to provide a 56-
decitex,
24-filament core-sheath composite yarn. Physical properties of the resulting
fiber are shown
in Table 2.
[0096]
The proportion of the residual hindered phenolic stabilizer in the resulting
core-sheath
composite yarn was a high 90%, and the strength retention rate after heat
treatment and the
AMR retention rate after heat treatment were high 75% and 80%, respectively.
[0097]
[Example 9]
Except for adjusting the hindered phenolic stabilizer (IR1010) and HALS type
stabilizer
(CHIMASSORB2020FDL) to 4 wt% and 4 wt%, respectively, relative to the weight
of the
core, the same procedure as in Example 1 was carried out to provide a 56-
decitex,
24-filament core-sheath composite yarn. Physical properties of the resulting
fiber are shown
in Table 2.
19
. CA 03006539 2018-05-28
,
=
,
[0098]
The proportion of the residual hindered phenolic stabilizer in the resulting
core-sheath
composite yarn was a high 93%, and the strength retention rate after heat
treatment and the
AMR retention rate after heat treatment were high 80% and 85%, respectively.
[0099]
[Example 10]
Except for adjusting the hindered phenolic stabilizer (IR1010) and HALS type
stabilizer
(CHIMASSORB2020FDL) to 1 wt% and 1 wt%, respectively, relative to the weight
of the
core, the same procedure as in Example 1 was carried out to provide a 56-
decitex,
24-filament core-sheath composite yarn. Physical properties of the resulting
fiber are shown
in Table 2.
[0100]
The proportion of the residual hindered phenolic stabilizer in the resulting
core-sheath
composite yarn was a high 75%, and the strength retention rate after heat
treatment and the
AMR retention rate after heat treatment were high 55% and 70%, respectively.
[0101]
[Table 2]
[Table 2]
_ ____________________
Example 6 Example 7
Example 8 Example 9 Example 10 .
polymer
polyether ester polyether ester
polyether ester polyether ester polyether ester
Core component amide copolymer amide copolymer amide
copolymer amide copolymer amide copolymer
_________________________________ relative viscosity 1.69
1.69 1.69 1.69 1.69
Sheath component polymer nylon 6 nylon 6
nylon 6 nylon 6 nylon 6
relative viscosity 2.71 2.71 2.71
2.71 2.71
- Core-sheath ratio core/sheath 70/30
30/70 30/70 30/70 30/70
Hindered phenolic type IR1010 IR1010
IR1010 IR1010 IR1010
content (wt%) 2.00 ____________ 3.00
3.00 4.00 1.00
stabilizer
----
________________ 5% weight loss temperature ( C) 351
351 351 351 351
CHIMASSROB CHIMASSROB
CHIMASSROB CHIMASSROB CHIMASSROB
type
2020FDL 2020FDL
2020FDL 2020FDL _______ 2020FDL
HALS type stabilizer
content (wt%) 2.00 2.00
3.00 4.00 1.00 _
________________ 5% weight loss temperature ( C) 404
404 404 404 404
spinning temperature ( C) 260 260
260 260 260
take-up speed (m/min) 2405 2405
2405 2405 2405
Yarn-making conditions draw ratio 1.5 1.5
1.5 1.5 1.5
product 3608 3608 3608 3608
3608
thermal setting temperature ( C) 150 150
150 150 150 P
fineness (dtex) 56 56
56 56 56
Physical properties of elongation percentage (%) 48
52 47 47 48 , 0
raw thread proportion of residual hindered
83 86
90 93 75 '
phenolic stabilizer (%)
.
strength (cN/dtex) 3.6 3.6 3.5
3.2 3.4 ,
*
T
strength after
51
Strength retention 2.2 2.5 2.8
2.6 1.9 1
heat treatment (cN/dtex)
r.,
0
retention rate (A) 60 70 75
80 55
AMR(%) 15.2 7.7 7.9 8.0
7.1
Hygroscopic AMR after
10.6 6.0
6.3 6.8 5.0
performance retention heat treatment (%)
retention rate ( /0) 70 78 80
85 70
Evaluation of cylindrical texture A S
S S A
knitted fabric after durability S S
S S A
tumble drying hygroscopicity retention A A
S S A
21
CA 03006539 2018-05-28
4
[0102]
[Comparative example 1]
Except for omitting the addition of a hindered phenolic stabilizer and a HALS
type stabilizer
and adjusting the strength retention rate after dry heat treatment to 30%, the
same
procedure as in Example 1 was carried out to provide a 56-decitex, 24-filament
core-sheath
composite yarn. Physical properties of the resulting fiber are shown in Table
3.
[0103]
The resulting core-sheath composite yarn had a AMR retention rate after dry
heat treatment
of 50%. After undergoing repeated tumble drying, the raw threads in the
resulting
core-sheath composite yarn were found to be hard or brittle and have a stiff
texture and an
inferior durability.
[0104]
[Comparative example 2]
Except for omitting the addition of a HALS type stabilizer (CHIMASSORB2020FDL)
and
adjusting the strength retention rate after dry heat treatment to 40%, the
same procedure as
in Example 1 was carried out to provide a 56-decitex, 24-filament core-sheath
composite
yarn. Physical properties of the resulting fiber are shown in Table 3.
[0105]
The proportion of the residual hindered phenolic stabilizer in the resulting
core-sheath
composite yarn was a low 40%, and the AMR retention rate after heat treatment
was 55%.
After undergoing repeated tumble drying, the raw threads in the resulting core-
sheath
composite yarn were found to be hard or brittle and have a stiff texture and
an inferior
durability. In addition, the hygroscopic performance deteriorated as a result
of thermal
degradation of the polyethylene glycol component contained in the polyether
ester amide
copolymer.
[0106]
[Comparative example 3]
Except for omitting the addition of a hindered phenolic stabilizer (IR1010)
and adjusting the
strength retention rate after dry heat treatment to 33%, the same procedure as
in Example 1
was carried out to provide a 56-decitex, 24-filament core-sheath composite
yarn. Physical
properties of the resulting fiber are shown in Table 3.
[0107]
The resulting core-sheath composite yarn had a AMR retention rate after heat
treatment of
52%. After undergoing repeated tumble drying, the raw threads in the resulting
core-sheath
composite yarn were found to be hard or brittle and have a stiff texture and
an inferior
durability. In addition, the hygroscopic performance deteriorated as a result
of thermal
degradation of the polyethylene glycol component contained in the polyether
ester amide
copolymer.
22
CA 03006539 2018-05-28
[0108]
[Comparative example 4]
Except for adjusting the hindered phenolic stabilizer (IR1010) and HALS type
stabilizer
(CHIMASSORB2020FDL) to 0.5 wt% and 0.5 wt%, respectively, relative to the
weight of the
core and adjusting the strength retention rate after dry heat treatment to
45%, the same
procedure as in Example 1 was carried out to provide a 56-decitex, 24-filament
core-sheath
composite yarn. Physical properties of the resulting fiber are shown in Table
3.
[0109]
The proportion of the residual hindered phenolic stabilizer in the resulting
core-sheath
composite yarn was a low 60%, and the AMR retention rate after heat treatment
was 65%.
After undergoing repeated tumble drying, the raw threads in the resulting core-
sheath
composite yarn were found to be hard or brittle and have a stiff texture and
an inferior
durability. In addition, the hygroscopic performance deteriorated as a result
of thermal
degradation of the polyethylene glycol component contained in the polyether
ester amide
copolymer.
[0110]
[Comparative example 5]
Except for using a hindered phenolic stabilizer with a 5% weight loss
temperature of 223 C
(IR1135, manufactured by BASF) and adjusting the strength retention rate after
dry heat
treatment to 40%, the same procedure as in Example 1 was carried out to
provide a
56-decitex, 24-filament core-sheath composite yarn. Physical properties of the
resulting fiber
are shown in Table 3.
[0111]
For the resulting core-sheath composite yarn, the proportion of the residual
hindered
phenolic stabilizer was 50% and the AMR retention rate after dry heat
treatment was 60%.
After undergoing repeated tumble drying, the raw threads in the resulting core-
sheath
composite yarn were found to be hard or brittle and have a stiff texture and
an inferior
durability. In addition, the hygroscopic performance deteriorated as a result
of thermal
degradation of the polyethylene glycol component contained in the polyether
ester amide
copolymer.
[0112]
[Comparative example 6]
Except for using a HALS type stabilizer with a 5% weight loss temperature of
275 C (Adeka
Stab LA-81, manufactured by Adeka Corporation) and adjusting the strength
retention rate
after dry heat treatment to 45%, the same procedure as in Example 1 was
carried out to
provide a 56-decitex, 24-filament core-sheath composite yarn. Physical
properties of the
resulting fiber are shown in Table 3.
[0113]
= 23
CA 03006539 2018-05-28
For the resulting core-sheath composite yarn, the proportion of the residual
hindered
phenolic stabilizer was 63% and the AMR retention rate after dry heat
treatment was 65%.
After undergoing repeated tumble drying, the raw threads in the resulting core-
sheath
composite yarn were found to be hard or brittle and have a stiff texture and
an inferior
durability. In addition, the hygroscopic performance deteriorated as a result
of thermal
degradation of the polyethylene glycol component contained in the polyether
ester amide
copolymer.
[0114]
[Comparative example 7]
Except for replacing the hindered phenolic stabilizer with a phosphorus-based
antioxidant
(Adeka Stab PEP-36, manufactured by Adeka Corporation, 5% weight loss
temperature
316 C) and adjusting the strength retention rate after dry heat treatment to
45%, the same
procedure as in Example 1 was carried out to provide a 56-decitex, 24-filament
core-sheath
composite yarn.
[0115]
The resulting fiber had a fineness of 56 decitex, an elongation percentage of
50%, a strength
of 3.0 cN/dtex, a AMR value of 6.7%, and a AMR retention rate after dry heat
treatment of
60%.
[0116]
After undergoing repeated tumble drying, the raw threads in the resulting core-
sheath
composite yarn were found to be hard or brittle and have a stiff texture and
an inferior
durability and hygroscopicity retention property. Thus, the phosphorus-based
antioxidant did
not work effectively.
[0117]
[Table 3]
24
[Table 3]
Comparative Comparative
Comparative Comparative Comparative Comparative
Comparative
example 1 example 2 example 3
example 4 example 5 _ example 6 _ example 7
polyether ester polyether ester
polyether ester polyether ester polyether ester polyether
ester polyether ester
polymer amide amide amide amide amide
amide amide
Core component
copolymer copolymer copolymer
copolymer copolymer copolymer copolymer
relative viscosity_ 1.69 1.69 1.69
1.69 1.69 1.69 1.69 _
Sheath polymer nylon 6 nylon 6 nylon
6 nylon 6 nylon 6 nylon 6 nylon 6
component relative viscosity 2.71 2.71 2.71
2.71 2.71 2.71 2.71
Core-sheath ratio core/sheath 30/70 30/70 30/70
30/70 30/70 30/70 30/70
Adeka Stab
type IR1010 IR1010
IR1010 IR1010 IR1135 IR1010
Hindered phenolic
_______________________________________________________________________________
___________________ PEP-36
stabilizer content (wt%) 0 2.00 0
0.50 2.00 2.00 2.00
5% weight loss temperature ( C) 351 351 351
351 223 351 316
CHIMASSROB CHIMASSROB CHIMASSROB CHIMASSROB CHIMASSROB
Adeka Stab CHIMASSROB
type
HALS type 2020FDL 2020FDL 2020FDL 2020FDL
2020FDL LA-81 2020FDL
stabilizer content (wt%) 0 0 2.00
0.50 2.00 2.00 2.00
5% weight loss temperature ( C) 404 404 404
404 404 275 404
spinning temperature ( C) 260 260 260
260 260 260 260
take-up speed (m/min) 2405 2405 2405
2405 2405 2405 2405
Yarn-making
draw ratio 1.5 1.5 1.5 1.5 1.5
1.5 1.5 P
conditions
product 3608 3608 3608 3608 3608
3608 3608 .
.
thermal setting temperature ( C) 150 150150
150 150 150 150 1 2
_
_
.
fineness (dtex) 56 56 56
56 56 56 56
Physical
properties of raw
elongation percentage (/0) 43 45 44
48 50 50 50
"
.
proportion of residual hindered
thread 0 40 0
60 50 63 -
,
phenolic stabilizer (%) .
,i,
strength (cN/dtex) 3.0 3.2 3.2
3.4 3.2 3.1 3.0 '
r.,
after
Strength retention strength0.9 1.3 1.1
1.5 1.3 1.4 1.4
heat treatment (cN/dtex)
retention rate (`)/0) 30 40 33
45 40 45 45
Hygroscopic AMR(%) 6.7 7.0 6.9 7.2
6.8 6.6 6.7
AMR after
performance 3.4 3.9 3.6 4.7
4.1 4.3 4.0
heat treatment (%)
retention
retention rate (%) 50 55 52
65 60 65 60
Evaluation of texture C C C
B C B B
cylindrical knitted durability C C C
C C C C
fabric after tumble
drying hygroscopicity retention C C C
C C C C
CA 03006539 2018-05-28
INDUSTRIAL APPLICABILITY
[0118]
The present invention can provide a core-sheath composite yarn that is high in
hygroscopic
performance, higher in comfortability than natural fibers, and able to
maintain a soft texture,
high durability, and moisture absorbing and releasing performance after
undergoing
repeated washing and drying.
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