Note: Descriptions are shown in the official language in which they were submitted.
CA 02421709 2003-08-26
.1.
DESCRIPTION
POLYESTER-BASED HEAT-BONDING CONJUGATE STAPLE FIBER
AND METHOD FOR PRODUCING THE SAME
The present invention relates to a polyester-based heat-bonding
conjugate staple fibers suitable for bonding a fiber structure such as
nonwoven fabric or waddiiig and to a method for producing the same, in
1o more detail to heat-bonding conjugate staple fibers capable of giving a
fiber structure which can thermally be bonded at relatively low
temperature and has good dimensional stability and to a method for
producing the same.
Heretofore, as polyester-based heat-bonding conjugate staple
fibers, conjugate fibers comprising a polyalkylene terephthalate such as
polyethylene terephthalate as a core component and an amorphous
polyester comprising isophthalic acid component, terephthalic acid
component, or the like as an acid constituent and not having a crystal-
melting point as a sheath component have widely been used, because of
being capable of being bonded at relatively low temperature of 120 to
1500C to form a fiber structure without needing a thermal treatment at
high temperature.
However, the polyester-based heat-bonding conjugate fibers can
form the fiber structure at the relatively low temperature, but has a
problem that the obtained fiber structure has insufficient dimensional
stability and is therefore largely deformed, when used under a high
temperature atmosphere.
The present inventors have tried drawing treatments and thermal
treatments at high temperature to solve the problem and improve the
dimensional stability of the heat-bonding fibers themselves, but it has be
found that the fibers are cohered each other at higher temperature than
the glass transition point of the amorphous polyester to make the
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production of yarns difficult.
From such the reason, it is the fact that heat-bonding conjugate
fibers containing an amorphous polyester, especially an amorphous
polyester having a glass transition point of 50 to 100 C, as a heat-bonding
component and having excellent dimensional stability have still not been
proposed.
The object of the present invention is to provide polyester-based
lo heat-bonding conjugate staple fibers capable of giving a high grade fiber
structure, such as nonwoven fabric or wadding, which can thermally be
bonded at relatively low temperature without needing a thermal treatment
at high temperature, has good dimensional stability and is hardly
deformed, even when used in a high temperature atmosphere, and to
provide a method for producing the same.
The present inventors have found that it is effective for the
achievement of the above-described object to use an amorphous polyester
having a glass transition point of 50 to 100 C as a heat-bonding
component and a polyalkylene terephthalate as a fiber-forming component
2o and select heat-drawing conditions for the fibers, and has thus completed
the present invention.
The polyester-based heat-bonding conjugate staple fibers of the present
invention,
are heat-bonding conjugate staple fibers comprising an amorphous polyester
having glass
transition point of 50 to 100 C and not having a crystal-melting point as a
heat-bonding
component and a polyalkylene terephthalate having a melting point of not less
than 220 C
as a fiber-forming component, characterized by having the number of crimps of
3 to 40
crimps / 25 mm, a crimp percent of 3 to 40%, and a web area shrinkage percent
of not
more than 20% defined as described below.
< Web area shrinkage percentage >
A card web nonwoven fabric comprising 100% of the heat-bonding
conjugate staple fibers and having an area of Ao and a basis weight of 30 g
/ m2 is left in a hot air dryer maintained at 1509C for two minutes, and
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then the area Al of the nonwoven fabric is measured. The web area
shrinkage percentage is determined by the following expressiol; :
Web area shrinkage percentage (%) =(Ao-Ai) / Ao X 100.
In addition, a method for producing polyester-based heat-bonding
conjugate staple fibers as the other object of the present invention, are
characterized by melting and conjugationally extruding an amorphous
polyester having a glass transition point of 50 to 100 C and not having a
crystal-melting point and a polyalkylene terephthalate having a melting
point of not less than 220 C, cooling and solidifying the conjugationally
1o extruded fibers, taking off the fibers at a rate of not more than 1,500 m
minute to form the undrawn conjugate fibers, imparting a polyether
polyester block copolymer to the undrawn conjugate fibers in an amount of
not less than 0.03 percent by weight on the basis of the weight of the fibers,
drawing the undrawn conjugate fibers in a draw ratio of 0.72 to 1.25 times
the cold maximum draw ratio at a temperature of T1 to (T2 + 30 C), and
further crimping the drawn fibers so as to give the number of crimps of 3
to 40 crimps / 25 mm and a crimp percent of 3 to 40%. Herein, Ti is either
higher temperature among the glass transition point of the amorphous
polyester and the glass transition point of the polyalkylene terephthalate,
2o and T2 is the glass transition point of the amorphous polyester.
The fiber-forming component of the polyester-based heat-bonding
conjugate staple fibers of the present invention is a polyalkylene
terephthalate having a melting point of not less than 220 C. When the
melting point of the polyester as the fiber-forming component is less than
220 C, it is not only difficult to stably produce the conjugate fibers, but
the
stability of the conjugate fibers is also deteriorated on a heat-bonding
treatment. The preferable concrete examples of the polyalkylene
terephthalate are polyethylene terephthalate and polybutylene
terephthalate, and may contain one or more copolymerization components
and additives such as a delustering agent, a coloring matter, and a
lubricant in small amounts within ranges not deteriorating the
characteristics, respectively. Especially, the polyethylene terephthalate
-4-
is more preferable because of being inexpensive and generally used.
On the other hand, the amorphous polyester used as the heat-
bonding component is a polyester having a glass transition point of 50 to
100'C and not having a crystal-melting point. When the glass transition
point of said polyester is less than 50 C, the polyester is not preferable,
because the fibers are easily cohered each other, when drawn by the
production method described later, and because the conjugate fibers
having excellent dimensional stability comprising an area shrinkage
percent of not more than 20% can not be obtained. When the glass
1o transition point exceeds 1001C, the polyester is also not preferable,
because
the thermal bonding property is deteriorated at low temperature of 120 to
150 C.
The amorphous polyester includes random or block copolymers
comprising acid components such as terephthalic acid, isophthalic acid, 2,
6-naphthalene dicarboxylic acid, 5-sodium sulfoisophthalic acid, adipic
acid, sebacic acid, azelaic acid, dodecane dicarboxylic acid, and 1,4-
cyclohexane dicarboxylic acid, and diols such as ethylene glycol, 1,3-
propanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, diethylene
glycol, 1,4-cyclohexanediol, and 1,4-cyclohexanedimethanol. Especially,
an amorphous copolyester comprising terephthalic acid component,
isophthalic acid component, ethylene glycol component and diethylene
glycol component is preferable from the points of costs and handleability.
When the above-described copolyester comprising the terephthalic
acid component, the isophthalic acid component, the ethylene glycol
component and the diethylene glycol component is used as the heat-
bonding component, it is necessary to set the copolymerization ratio so
that the glass transition point of the copolyester is included within the
above-described range. However, the molar ratio of the terephthalic acid
component : the isophthalic acid component is suitably 50 : 50 to 80 : 20,
and the molar ratio of the ethylene glycol component : the diethylene glycol
component may arbitrarily be selected within a range of 0: 100 to 100 : 0.
When the heat-bonding component occupies all parts or a part
of the surfaces of the fibers (preferably not less than 40%, especially not
less than 60%, of the surfaces of the fibers) in the polyester-based heat-
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bonding conjugate staple fibers of the present invention, the polyester-
based heat-bonding conjugate staple fibers may be produced in any
conjugate form selected from a sheath-core type form, an eccentric sheath-
core type form, a side-by-side type form, a sea-island type form, a split type
from, and the like. In particular, the sheath-core type form, the eccentric
sheath-core type form, and the side-by-side type form are more preferable.
Next, it is necessary that the number of crimps and the crimp
percent of the polyester-based heat-bonding conjugate staple fibers of the
present invention are 3 to 40 crimps / 25 mm and 3 to 40%, respectively.
1o When the staple fibers have the number of crimps of less than less than 3
crimps / 25 mm or a crimp percent of less than 3%, the fibers are not
preferable, because the degree of entanglement between the staple fibers is
insufficient to deteriorate the card passage of the staple fibers, whereby
the high grade fiber structure is not obtained. On the other hand, when
the staple fibers have the number of crimps of more than 40 crimps / 25
mm or a crimp percent of more than 40%, the fibers are also not preferable,
because the degree of entanglement between the staple fibers is too large
to sufficiently card the staple fibers, whereby a high grade fiber structure
is not obtained. The number of crimps and the crimp percent are more
preferably 5 to 30 crimps / 25 mm and 5 to 30%, respectively. The form of
the crimps includes mechanical crimps and three-dimensional crimps, and
may suitably be selected and set in response to the use or aim of the staple
fibers.
The length and single fiber fineness of the polyester-based heat-
bonding conjugate staple fibers do not need to be especially limited, and
may suitably be set in response to the use and aim of the staple fibers.
In the heat-bonding conjugate staple fibers of the present
invention, it is important that the web area shrinkage percent defined as
described below is not more than 20%. Thereby, said conjugate staple
fibers can be processed in the form of 100% or in the form of a blend with
other fibers to obtain a fiber structure having excellent dimensional
stability even in high temperature atmosphere. When the shrinkage
percent exceeds 20%, the fiber structure having excellent dimensional
stability in a high temperature atmosphere can not be obtained. The web
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area shrinkage percent is more preferably not more than 10%.
< Web area shrinkage percentage >
A card web nonwoven fabric comprising 100% of the heat-bonding
conjugate staple fibers and having an area of Ao and a basis weight of 30 g
/ m2 is left in a hot air dryer maintained at 150t for two minutes, and
then the area Ai of the nonwoven fabric is measured. The web area
shrinkage percentage is determined by the following expression.
Web area shrinkage percentage (%) =(Ao-A) / Ao X 100
The above-mentioned polyester-based heat-bonding conjugate
staple fibers of the present invention can efficiently be produced, for
example, by the following method. Namely, the above-mentioned
amorphous polyester and the polyalkylene terephthalate are conjugated,
preferably conjugated in the form of a sheath-core type, an eccentric
sheath-core type, or a side-by-side type, melted and extruded. The
extruded fibers are taken off at a speed of less than 1,500 m/ minute to
obtain the undrawn conjugate fibers. Then, the obtained undrawn
conjugate fibers are subjected to the addition of a polyether polyester block
copolymer in an amount of not less than 0.03 percent by weight on the
basis of the weight of said fibers, drawn in a draw ratio of 0.72 to 1.25
times the cold maximum draw ratio at a temperature of Ti to (T2 + 30cc),
and further crimped into the crimped fibers having the number of crimps
of 3 to 40 crimps / 25 mm and a crimp percent of 3 to 40%, and then cut in
a desired length, thus enabling to produce the polyester-based heat-
bonding conjugate staple fibers. Herein, Ti is either higher temperature
among the glass transition point of the amorphous polyester and the glass
transition point of the polyalkylene terephthalate, and T2 is the glass
transition point of the amorphous polyester.
A take-off speed exceeding 1,500 m / minute is not preferable,
because the web area shrinkage percent can not be reduced to not more
than 20%, even when the obtained undrawn conjugate fibers are drawn in
the above-described conditions.
The first point on the above-described production method is to add
the polyether polyester block copolymer to the surfaces of the conjugate
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fibers at a stage before the taken undrawn conjugate fibers are drawn.
Thereby, even when the undrawn conjugate fibers are drawn at a
temperature not less than the glass transition point T2 of the amorphous
polyester (namely, corresponding to the softening point of the amorphous
copolyester), the polyester-based heat-bonding conjugate staple fibers
having a web area shrinkage percent of not more than 20% can be
obtained without causing cohesion between the fibers in the drawing
process, when the drawing temperature is not more than T2 + 30'C.
Further, the fiber structure having excellent mechanical characteristics
1o can be obtained, because the heat-bonding property of the conjugate fibers
is not deteriorated so much, even when said polyether polyester block
copolymer is applied to the surfaces of the conjugate fibers.
Such the simultaneous achievements of the cohesion-preventing
effect and the heat-bonding property-maintaining effect are impossible
with an anionic surfactant or its polyoxyalkylene adduct, a cationic
surfactant, a nonionic surfactant, a mineral oil, or the like, which has
usually been used as an oiling agent for producing staple fibers, or even
with a polysiloxane-based treating agent.
A preferably used polyether polyester block copolymer includes
especially a copolymer comprising terephthalic acid component and
isophthalic acid component and / or an alkali metal sulfoisophthalic acid
component in a molar ratio of 40 : 60 to 100 : 0 as a dicarboxylic acid
component and ethylene glycol as a glycol component and copolymerized
with 20 to 95 percent by weight of a polyalkylene glycol having a number-
average molecular weight of 600 to 10,000, and the copolymer is especially
preferable from the point of the stability of an aqueous emulsion and the
point of an cohesion generation-preventing effect in a drawing process.
An acid component such as adipic acid, sebacic acid, azelaic acid, dodecane
dicarboxylic acid, or 1, 4-cyclohexanedicarboxylic acid and / or a diol
component such as 1, 3-propanediol, 1, 4-butanediol, 1, 5-pentanediol, 1, 6-
hexanediol, diethylene glycol, 1, 4-cyclohexanediol, or 1, 4-cyclohexane
dimethanol may be copolymerized in small amounts. Additionally, in
order to adjust the molecular weight, one end of the polyalkylene glycol
may be sealed with an ether bond such as a monomethyl ether, a
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monoethyl ether, or a monophenyl ether. The polyalkylene glycol
includes polyethylene glycol, ethylene oxide - propylene oxide copolymer,
polypropylene glycol, and polytetramethylene glycol. The polyethylene
glycol is especially preferable.
The number-average molecular weight of the polyether polyester
block copolymer is preferable to be in the range of 3,000 to 20,000, because
of giving a higher cohesion-preventing effect.
The amount of the polyether polyester block copolymer adhered to
the undrawn fibers is necessary to be not less than 0.03 percent by weight
1o on the basis of said undrawn fibers. An amount of less than 0.03 percent
by weight is not preferable, because a sufficient cohesion-preventing effect
is not obtained in the drawing process described later. On the other hand,
the cohesion-preventing effect reaches the highest limit and does not
increase, even when the adhesion amount is increased. Therefore, an
amount of not more than 0.5 percent by weight, especially a range of 0.05
to 0.3 percent by weight, is suitable.
A method for applying the polyether polyester block copolymer to
the surfaces of the undrawn conjugate fibers is especially not limited, and
the polyether polyester block copolymer may be applied by an arbitrary
conventional known method usually in the form of an aqueous emulsion
solution. In order to stabilize said emulsion solution, not only an
emulsifier but also additives such as an antistatic agent, a lubricant, a
rust-preventing agent, an antifungal agent, and an antibacterial agent
may be added.
Next, the second point on the above-described production method
is a drawing temperature. Although it is undoubtedly necessary to set
the drawing temperature to a temperature of not less than T2 (glass
transition point of the amorphous copolyester), it is simultaneously needed
for the thermal setting of the polyalkylene terephthalate of fiber-forming
component to set the drawing temperature to a temperature of not less
than the glass transition point of the polyalkylene terephthalate. Even if
the above-described polyether polyester block copolymer is preliminarily
imparted to the surfaces of the undrawn conjugate fibers, the target heat-
bonding conjugate staple fibers having the excellent dimensional stability
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.9.
by the present invention may not be obtained, when the drawing
temperature is lower than either one of the glass transition points of the
amorphous copolyester and the polyalkylene terephthalate. Further, it is
also important not to set the drawing temperature to high temperature
exceeding T2 (glass transition point of the amorphous copolyester) + 301C.
When the drawing temperature exceeds T2 + 30 C, the cohesion of the
amorphous copolyester can sufficiently not be prevented , and the
generation of fused fiber bundles and the deterioration in the stability of a
crimper on the addition of crimps to the fibers by the use of a push type
crimper are caused. Thereby, the drawing temperature exceeding T2 +
301C is not preferable.
When the drawing temperature is included in the above-described
range, the above-described drawing may be one step drawing or more step
drawing, but it is necessary that the total draw ratio is 0.72 to 1.25 times
the cold draw ratio. When the draw ratio is less than 0.72 time the cold
draw ratio, the draw ratio is not preferable, because the dimensional
stability of the produced fiber structure is deteriorated. When the draw
ratio is more than 1.25 times the cold draw ratio, the draw ratio is also not
preferable, because the decrease in the heat-bonding property as well as
the deterioration in the drawing property are caused. The cold draw ratio
of the undrawn fibers is obtained by drawing the undrawn conjugate fibers
collected within five minutes from the just spun time at a speed 5 cm /
second in an initial chuck length of 10 cm in air having a relative humidity
of 65% at 250C, and then dividing the distance between the initial chuck
length and the chuck length at a time when the chuck can not be elongated,
by the initial chuck length (10 cm).
In the present invention, it is effective for the improvement of the
dimensional stability and for the prevention of the cohesion that the
above-described drawing is carried out in a draw ratio of 0.7 to 1.0 time
the cold draw ratio of the undrawn conjugate fibers at a temperature of T1
(either higher temperature among the glass transition point of the
amorphous copolyester and the glass transition point of the polyalkylene
terephthalate) to (Ti + 101C) and then in a draw ratio of 1.03 to 1.25 at a
temperature of (Ti + 101C) to [T2 (glass transition point of the amorphous
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copolyester) + 301C].
Additionally, it is especially effective to use hot water as a
drawing heating medium.
The drawn conjugate fibers are crimped in conditions giving the
number of crimps of 3 to 40 crimps / 25 mm and a crimp percent of 3 to
40% by a known conventional method, and then cut in a desired length.
Namely, when the crimping form is a mechanical crimp form, for example,
a stuffing type crimper is used, and the conditions of the stuffing pressure
and temperature may suitably be controlled. On the other hand, when
the crimping form is a three-dimensional crimp form, the conjugate
structures of the conjugate fibers and cooling conditions at the spinning
time may suitably be selected.
The obtained polyester-based heat-bonding conjugate staple fibers
of the present invention have good dimensional stability, and are suitable
for fiber structures such as nonwoven fabrics or wadding. The heat-
bonding conjugate staple fibers may singly be used for the fiber structures
such as the nonwoven fabrics, or the heat-bonding conjugate staple fibers
as main fibers may be blended with other fibers and then used for the fiber
structures such as the nonwoven fabrics.
Examples
The present invention will be explained more concretely hereafter
with examples. Therein, evaluation items in Examples obeyed the
following methods.
(a) Glass transition point (Tg), melting point (Tm)
The glass transition point (Tg) and the melting point (Tm) were
measured with a differential scanning calorimeter DSC-7 type
manufactured by Perkin-Elmer Inc. at a temperature-rising rate of 20'C /
minute.
(b) Intrinsic viscosity ([ 77 ]).
The intrinsic viscosity was measured in ortho-chlorophenol as a
solvent at a temperature of 35 C.
(c) Number of crimps, crimp percent
The number of crimps and the crimp percent were measured by a
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method described in JIS L 1015 7. 12.
(d) Fineness
The fineness was measured by a method described in JIS L 1015 7.
5. 1 A method.
(e) Fiber length
The fiber length was measured by a method described in JIS L
1015 7. 4. 1 C method.
(f) Oil pickup
A value obtained by measuring the weight of residues extracted
from fibers with 30'C methanol in a bath ratio of 1: 20 for 10 minutes and
then dividing the measured weight by a prescribed fiber weight.
(g) Web area shrinkage percent and deformation of fiber structure
The area shrinkage percent was determined by forming a card
web comprising 100% of the heat-bonding conjugate staple fibers having a
basis weight of 30 g / m2 and an area Ao (25 cm X 25cm = 625cm2), leaving
the formed card web in a hot air drier (hot air circulation constant-
temperature drier : 41-S4, manufactured by Satake Kagaku Kikai Kogyo
Kabushiki Kaisha) maintained at 150cC for two minutes, measuring the
area Ai of the thermally treated card web and then applying the area Al to
the following expression. The card web having an area shrinkage percent
of not more than 20% was accepted.
Area shrinkage percent (%) = (625 - A) / 625 X 100
(h) Cohesion
When the cohesion was generated on the drawing of the fibers to
make the production impossible or when a cohered bonding was confirmed
in the card web, the fibers were judged to be defective, and in other cases,
the fibers were judged to be good.
[Example 1]
Polyethylene terephthalate having an intrinsic viscosity of 0.64, a
Tg of 67 C and a Tm of 256t was used as a fiber-forming component.
An amorphous copolyester copolymerized from terephthalic acid
component and isophthalic acid component in a molar ratio of 60 : 40 as an
acid component and ethylene glycol and diethylene glycol in a molar ratio
12-
of 95 : 5 as a diol component, and having an intrinsic viscosity of 0.56 and
a Tg of 64 C was used as a heat-bonding component. The pellets of the
polymers were vacuum-dried, fed into a sheath-core type conjugate melt-
spinning device and melt-spun from a spinneret having 450 spinning
nozzles in a conjugate ratio comprising a volume ratio of 50 / 50 at a
spinning temperature of 2901C in an extrusion rate of 650 g / minute.
The spun fibers were cooled with 30t cold air, subjected to the adhesion
of a treating agent comprising the emulsion of a polyether polyester block
copolymer copolymerized from terephthalic acid component and
1o isophthalic acid component in a molar ratio of 80 / 20 as an acid
component,
ethylene glycol as a glycol component, and polyethylene glycol having a
number-average molecular weight of 3,000 and having an average
molecular weight of 10,000 in a pure content of 0.1 percent by weight on
the basis of the fibers by the use of an oiling roller, and then taken off at
a
rate of 900 m / minute to obtain the undrawn sheath-core type conjugate
fibers. The cold maximum draw ratip (hereinafter, referred to as CDR) of
the undrawn fibers was 4.5.
The undrawn conjugate fibers were bundled to form the tow of
110,000 dtex (100,000 denier). The tow was first drawn in a draw ratio of
2o 3.5 (0.78 time CDR) in 72C hot water, further drawn in a draw ratio of
1.15 (total draw ratio is 4.0; 0.89 time CDR) in 80'C hot water, oiled with
a spinning oil comprising potassium laurylphosphate, naturally cooled to
35t, crimped with a stuffing type crimper, and then cut in a fiber length
of 51 mm to obtain the heat-bonding conjugate staple fibers having a
single fiber fineness of 4.4dtex, the number of crimps of 10 crimps / 25 mm
and a crimp percent of 15%.
[Examples 2 to 10, Comparative Examples 1 to 61
Heat-bonding conjugate stable fibers having a single fiber
fineness of 4.4 dtex, a fiber length of 51 mm, the number of crimps of 10
crimps / 25 mm, and a crimp percent of 15% were obtained in the same
conditions as in Example 1 except that the heat-bonding component, the
fiber-forming component, the treating agent, the drawing ratio, and the
drawing temperature were changed.
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13-
The fiber constitutions, treating agent kinds, spinning and
drawing conditions, and fiber evaluation results of the Examples and the
Comparative Examples are shown in Tables 1, 2, 3, and 4, respectively.
s Table 1
Conjugate Type F 1 F 2 F 3 F 4 F 5 F 6
Acid T A 60 60 55 70 75 60
Component I A 40 40 40 30 25 40
SA - - 5 - - -
# Glycol E G 95 100 100 62 44 95
Component D E G 5 - - 8 6 5
I H M G - - - 30 50 -
T g r, 64 69 59 55 40 64
Tm C - - - - - -
[ rJ ] 0.56 0.57 0.55 0.56 0.56 0.56
Polymer PET PET PET PET PET PBT
# T g C 67 67 67 67 67 25
II Tm C 256 256 256 256 256 228
[ rJ ] 0.64 0.64 0.64 0.64 0.64 0.87
# I ~ Heat-bonding component
# II : Fiber-forming component
TA : Terephthalic acid IA : Isophthalic acid SA: Sebacic acid
EG : Ethylene glycol DEG : Diethylene glycol
HMG : Hexamethylene glycol
PET : Polyethylene terephthalate
PBT : Polybutylene terephthalate
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Table 2
Treating agent 01 02 03 04 05
Polyether polyester block - -
copolymer component
Acid T A 80 90 72
component I A 20 10 18
SIA - - 10
Glycol E G 100 100 100
component
Polyalkylene Type PEG3000 M-PEG3000 PEG4000
glycol C D 70 80 70
Number-average molecular 10000 9000 11000
weight
Other components - - - Phosphate Phosphate
1 2
TA : Terephthalic acid IA : Isophthalic acid
SIA : 5-Sodium sulfophthalic acid
PEG 3000 ~ Polyethylene glycol having an average molecular weight of
3000
PEG 4000 ~ Polyethylene glycol having an average molecular weight of
4000
M-PEG 3000 : Polyethylene glycol monophenyl ether having an average
molecular weight of 3000
CD : Copolymerization degree %
Phosphate 1 : Potassium lauryl phosphate
Phosphate 2 : Partial potassium lauryl phosphate having
the average ethylene oxide addition number of five moles.
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Table 3
Spinning Drawing
# 1 Treating C D R First step Second step Total drawing
agent ratio
# 2 Ratio # 2 Ratio Ratio(CDR)
/CDR /CDR
Example 1 Fl 01 4.5 72 0.78 72 1.15 4.00(0.89)
Comparative
F1 O1 4.5 65 0.78 60 1.15 4.00(0.89)
example 1
Comparative
Fl 04 4.5 65 0.78 60 1.15 4.00(0.89)
example 2
Comparative
Fl 04 4.5 72 0.78 72 1.15 4.00(0.89)
example 3
Comparative
Fl 05 4.5 72 0.78 72 1.15 4.00(0.89)
example 4
Example 2 Fl O1 4.5 72 0.78 80 1.15 4.00(0.89)
Example 3 Fl 01 4.5 72 0.78 85 1.15 4.00(0.89)
Example 4 Fl O1 4.5 72 0.96 80 1.05 4.54(1.01)
Comparative
Fl 01 4.5 72 0.60 72 1.15 3.10(0.69)
example 5
Example 5 Fl 02 4.5 72 0.78 72 1.15 4.00(0.89)
Example 6 Fl 03 4.5 72 0.78 72 1.15 4.00(0.89)
Example 7 F2 01 4.5 72 0.78 72 1.15 4.00(0.89)
Example 8 F3 01 4.5 72 0.78 72 1.15 4.00(0.89)
Example 9 F4 01 4.5 72 0.78 72 1.15 4.00(0.89)
Comparative
F5 O1 4.5 72 0.78 72 1.15 4.00(0.89)
example 6
Example 10 F6 01 3.8 72 0.78 72 1.15 3.38(0.89)
# 1 : Conjugate type
# 2 : Temperature
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Table 4
Fiber
Appearance of Web area shrinkage Web grade after
Un-cohesion percent shrinkage
M
Example 1 Good 18. 5 Good
Comparative
Good 7 3. 9 Defective
example 1
Comparative
Good 5 5. 3 Defective
example 2
Comparative
Defective Could not be drawn -
example 3
Comparative
Defective Could not be drawn -
example 4
Example 2 Good 8. 1 Good
Example 3 Good 5. 1 Good
Example 4 Good 6. 8 Good
Comparative
Defective Could not be drawn -
example 5
Example 5 Good 17. 5 Good
Example 6 Good 18. 1 Good
Example 7 Good 18. 3 Good
Example 8 Good 16. 3 Good
Example 9 Good 16. 1 Good
Comparative
Defective Could not be drawn -
example 6
Example 10 Good 14. 8 Good
CA 02421709 2003-03-07
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. 17 .
The polyester-based heat-bonding conjugate staple fibers of the
present invention can provide high-grade fiber structures which have good
diinensional stability and hardly cause deformation, even when used
under high temperature atmospheres, although the fiber structures can be
formed at relative low temperature. In addition, by the production
method of the present invention, the above-described heat-bonding
conjugate staple fibers can extremely stably and easily be produced
without causing cohesion.
