JP2003278039A - Polyester composite false twisted yarn - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a polyester composite false twisted yarn having both large fullness and a soft and pliant surface touch and excellent process passableness after weaving. <P>SOLUTION: The polyester composite false twisted yarn is composed of a polyester multifilament yarn A and a core/sheath conjugated multifilament yarn B in which polystyrene constitutes a core part and a polyester constitutes a sheath part. In the polyester composite false twisted yarn, the multifilament yarn A constitutes a core yarn and the multifilament yarn A and the multifilament yarn B have relationships a to d. a. <5% difference in yarn length between the multifilament yarn A and the multifilament yarn B of the composite false twisted yarn, b. ≥5 and ≤35% difference in yarn length between the multifilament yarn A and the multifilament yarn B in the composite false twisted yarn after a dry heat treatment at 180°C after boiling water treatment, c. ≤10 cN/dtex initial Young's modulus of the multifilament yarn B and d. ≤20% stretch elongation percentage of the composite false twisted yarn. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a polyester composite false twisted yarn composed of two or more kinds of polyester multifilaments. More specifically, a yarn length difference that does not impair the high-order passing property is expressed during yarn processing, and a yarn dyeing process is performed on the woven or knitted fabric, and then a conventional dyeing process is performed to cause a yarn length difference due to a contraction difference between the core and the sheath. The present invention relates to a polyester composite false-twisted yarn capable of imparting a bulge and a soft texture which have never been obtained to a woven or knitted fabric.

[0002]

2. Description of the Related Art Polyester has been used in a wide range of fields from clothing applications to material applications because it has excellent mechanical properties. For clothing applications, development has been carried out with the aim of how to impart the texture and functionality of natural fibers.

The false twisting method is a means originally developed for imparting the bulkiness to a woven or knitted fabric by giving the crimp of the wool fiber to the synthetic fiber. It is an effective means for developing into knitted fabrics.

However, the false twisted yarn composed of one type of multifilament has a drawback that the bulkiness is lost when it is formed into a woven or knitted fabric, and as a means for overcoming such a problem, 2 having different yarn physical properties is used. So-called composite false twisted yarns composed of more than one kind of multifilament have been studied and developed. Means for obtaining composite false-twisted yarn can be broadly classified into a spinning-mixing method in which yarns having different properties are mixed during spinning, and a post-mixing method in which separately spun yarns are mixed during false-twisting process. It is widely adopted as a method capable of imparting a large difference in yarn length due to the difference in the physical properties of each of the composite yarns. The difference in the physical properties of the yarn is generally a difference in elongation, a difference in spinning speed, a difference in single fiber fineness, and the like.

For example, Japanese Patent No. 2892649 proposes a technique of giving a soft and supple touch to a woven or knitted fabric by giving a low crimping property and a difference in yarn length, but a large yarn length when receiving heat in a dyeing process. It does not cause a difference and cannot give a sufficient bulge. Also, no consideration was given to the Young's modulus of the sheath yarn, and although the flexibility due to the low crimpability could be imparted, the powder-touch feel due to the low Young's modulus of the single fibers constituting the sheath yarn was imparted. Absent.

Further, there is also a method in which fibers having different fineness are simultaneously spun using a spinneret having pores having different pore diameters to obtain a highly oriented undrawn yarn, which is false twisted into a false fineness false twisted yarn. Although proposed, in such cases, thick filaments with single fiber fineness are more difficult to cool than filaments with fine single fiber fineness in the cooling process of spinning, so thick filament yarns with single fiber fineness become filaments with fine single fiber fineness. In comparison, the orientation becomes lower and the elongation becomes larger than that of a filament having a fine single fiber. When such a filament group is false-twisted, strong tension acts on the thin filaments of the single fiber fineness on the low elongation side, and thus the thin filament of the single fiber fineness is formed at the center of the processed yarn and the filament of the single fiber fineness is formed on the outer layer. Since the thick filaments are located, the woven or knitted fabric is far from the ideal having a firm touch and a weak stiffness. Also, the difference in yarn length is at most about several percent, and the bulge of the woven or knitted fabric becomes poor.

Generally, in false twisting, a high false twist number and a high set temperature are applied to highly crystallize the fibers to impart a strong and robust crimp to give a large bulge to the woven or knitted fabric. On the other hand, the surface touch of the woven or knitted fabric has the drawback of becoming stiff.

Japanese Unexamined Patent Publication No. 10-88418 discloses a polyester multifilament yarn and a polystyrene core.
A composite false twisted yarn composed of a core-sheath type composite multifilament yarn having polyester as a sheath portion is disclosed, but no consideration is given to the initial Young's modulus of the single fiber of the core / sheath type composite yarn.

[0009]

The present invention overcomes the drawbacks of the conventional false twisted yarns as described above, and
It is an object of the present invention to provide a composite false-twisted yarn having both a large bulge and a soft surface touch and excellent processability during weaving.

[0010]

The polyester composite false twisted yarn of the present invention has the following constitution in order to solve the above problems.

That is, a composite false twisted yarn composed of a polyester multifilament A and a core / sheath type composite multifilament B in which polystyrene constitutes a core portion and polyester constitutes a sheath portion, wherein the polyester multifilament A is The polyester composite false twisted yarn is characterized in that the polyester multifilament A and the core / sheath type composite multifilament B have the following relationships a to d while constituting a core yarn.

A. The difference in yarn length between the polyester multifilament A of the composite false twisted yarn and the core / sheath type composite multifilament B is less than 15% b. In the composite false-twisted yarn subjected to the dry heat treatment at 180 ° C. after the boiling water treatment, the yarn length difference between the polyester multifilament A and the core / sheath composite multifilament B is 15% or more and 35% or less c. The initial Young's modulus of the core / sheath type composite multifilament B is 10 cN / dtex or less d. Expansion and contraction rate of composite false twisted yarn is 20% or less

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION The mixed yarn of the present invention comprises a polyester multifilament A and a core / sheath type composite multifilament B in which polystyrene constitutes a core and polyester constitutes a sheath.

The multifilament B has the form of a core / sheath type composite yarn in which polystyrene is used as the core and polyester is used as the sheath. This utilizes the effect that polystyrene suppresses the orientation of the polyester polymer during the cooling and solidification process in the spinning process.

Due to this effect, when a polyester polymer in which a polystyrene polymer is composited and a single polyester polymer are simultaneously spun, the former becomes a filament in which the orientation is suppressed more than the latter, resulting in a yarn with a lower shrinkage. However, the difference in yarn length is increased, and a large bulge can be expressed in a woven or knitted fabric.

The polystyrene composite ratio of the multifilament B is preferably 3 to 15% by weight. When the content is less than 3%, the effect of suppressing orientation by polystyrene becomes poor. Further, the expansion / contraction elongation tends to increase, which is not preferable. If the content exceeds 15%, the polyester constituting the sheath portion may be cracked and the strength tends to be reduced.

The polyester multifilament A constitutes the core yarn of the composite false twisted yarn, and it is preferable that the polyester multifilament A has a high shrinkability in order to obtain a large yarn length difference. Therefore, it is preferable to use a polymer obtained by copolymerizing the third component with homopolyester such as polyethylene terephthalate, polybutylene terephthalate, and polytrimethylene terephthalate. The copolymerization component can be used without particular limitation, but isophthalic acid is generally used, and the copolymerization rate is 3
When it is set to 12 mol%, a sufficiently high shrinkable fiber can be obtained.

In the false-twisted composite yarn of the present invention, the difference in yarn length between the multifilament A and the multifilament B is less than 15%. More preferably, it is less than 10%. Thread length difference is 15
If it exceeds%, it may cause loosening when splitting the twisted yarn.

The composite false twisted yarn of the present invention is treated with boiling water to obtain 1
It is important that the yarn length difference is 15% or more and 35% or less by the dry heat treatment at 80 ° C. As a result, the yarn length difference is exhibited by the heat treatment during dyeing of the woven or knitted fabric, and a large bulge can be imparted to the woven or knitted fabric. If the difference in yarn length is less than 15%, a sufficient bulge cannot be obtained when it is made into a woven or knitted product, and if it exceeds 35%, the fluffiness becomes large, and an ideal moderate bulge cannot be imparted.

Since the multifilament B forming the sheath yarn of the composite yarn forms the surface layer portion of the woven or knitted material, it has a great influence on the surface touch of the woven or knitted material. In order to obtain a soft and supple surface touch, it is important that the initial Young's modulus of the filament of the sheath yarn is 10 cN / dtex or less.
For that purpose, it is preferable to give due consideration to the setting of the spinning speed and the draw ratio. For example, the spinning speed is 2700 to 320.
In the case of 0 m / min, if the draw ratio is 1.5 to 1.9 times, the initial Young's modulus of the single filament of the sheath yarn will be a target value. In addition, the monofilament fineness of the multifilament B is 1.5 dtex in order to obtain a soft and supple surface touch.
The following is preferable.

The elastic extension ratio of the composite false twisted yarn of the present invention is 20%.
It is important that it is below, preferably 15% or below. When the expansion and contraction rate exceeds 20%, the crimp of the composite false-twisted yarn becomes strong, the slimy feeling peculiar to the false-twisted textured yarn of the woven or knitted fabric becomes strong, and the surface touch of the woven or knitted fabric becomes rough.

In order to increase the firmness and elasticity, it is sufficient to increase the bending moment of the core yarn. For that purpose, it is effective to increase the single fiber fineness. Fiber fineness of 4.4 dtex
The above is preferable.

Furthermore, it is preferable that the cross-sectional shape of the monofilament of the multifilament A is a hollow cross section. The hollow cross-section yarn enhances the cooling effect of the fiber during spinning, promotes the orientation of the fiber in the cooling and solidifying process in the spinning step,
The yarn has a high Young's modulus and improves the elasticity and firmness.

The entanglement number of the composite false-twisted yarn of the present invention is 20 / from the viewpoint of keeping the pang looseness good when splitting the twisted yarn.
It is preferably m or more.

The mixed yarn of the present invention is not particularly limited in fineness, single fiber fineness, number of filaments, and cross-sectional shape. For example, the cross-sectional shape may be a hollow or three-lobed modified cross-section. There may be such differences between species of multifilaments.

However, in order to give the woven or knitted fabric a resilience and a soft feeling, it is preferable to make the monofilament fineness of the core yarn contributing to the resilience thick and the fineness of the sheath yarn contributing to the soft feeling thin. Therefore, the multifilament B that is the core yarn
It is preferable that the single fiber fineness Db of No. 3 is equal to or more than the single fiber fineness Da of the multifilament A that forms the sheath yarn. That is,
It is preferable that the relationship Da ≦ Db is satisfied.

Further, particles may be added to the polyester portion of the multifilament A and the polyester multifilament B for the purpose of improving color developability and matting.

[0028]

The present invention will be described in more detail with reference to examples, but the present invention is not limited thereto. In addition, each physical-property value in the text and an Example is based on the following measuring methods. (1) Disassembled yarn Yarn length difference Take out a yarn of an appropriate length and carefully disassemble it into individual fibers so that the fibers themselves do not stretch. The decomposed monofilament is placed on a scale plate coated with glycerin, and the monofilament is stretched to such an extent that there is no crimp or crimp, and the length L of one monofilament is measured (up to a unit of 1 mm). The short fiber group is classified into a short fiber group and a long fiber group, and the short fiber group has an average length of L1 and a long fiber group of L2. The average value of 5 measurements is taken as the measured value.

Disassembled yarn Yarn length difference (%) = {(L2-L1) /
L1} × 100 (2) Initial Young's modulus of monofilament The monofilament decomposed into individual monofilaments was tested with a tensile tester manufactured by Instron Co., Ltd., and had a test length of 2 cm and a tensile speed of 2 cm
/ Min, a tensile test was conducted, and the straight line of the slope of the rising curve of the obtained S-S curve was extended to obtain an elongation of 100%.
The value obtained by finding the strength at time and dividing it by the fineness (cN / d
tex). The average value of 10 measurements is taken as the measured value. (3) Make a skein under the load of expansion and contraction rate 0.00088 cN / dtex,
After soaking in hot water at 90 ± 2 ° C. for 30 minutes under a load of 0.00088 cN / dtex, the load is removed and the product is naturally dried. Subsequently, a load of 0.00088 cN / dtex was applied and the length L1 of the skein after 30 seconds was measured, and then the skein length L1 was measured.
A load of 088 cN / dtex is applied and the skein length L2 after 30 seconds is measured.

Stretching elongation rate (%) = 100 × (L2-L1) / L2 (Example 1) 8 mol% isophthalic acid and 2-2 bis [4-
(2-Hydroxyethoxy) phenyl] propane 5 mol% and a total of 87 mol% of ethylene glycol and terephthalic acid were copolymerized with a hollow hollow cross section, and polystyrene was compounded in the core portion at a weight ratio of 10.5%. Spinning speed 32 with core-sheath type composite polyester with round cross section with the same spinneret
Simultaneous spinning and mixed fiber at 00 m / min, 150 dtex-
An unstretched mixed filament yarn of 45 filaments (core yarn 75dtex-9 filaments, sheath yarn 75dtex-36 filaments) was obtained. This unstretched mixed fiber is a standard 3
After false twisting and stretching at a false twisting temperature of 130 ° with a shaft type friction disk false twisting machine, the fibers are mixed by an interlace air nozzle, and 84 dtex-45 filament (core yarn 42 dtex-9
A composite false twisted yarn of filament and sheath yarn 42dtex-36 filament) was obtained.

The form of the obtained false-twisted composite yarn was as shown in FIG. 2, and the difference in yarn length was 11%. After the boiling water treatment for 15 minutes and the dry heat treatment at 180 ° C. for 5 minutes, the yarn form was as shown in FIG. 3, and the yarn length difference was 31%. Table 1 shows the physical properties of other composite false twisted yarns.

Next, after the false twisted yarn is actually twisted at 1000 T / m, it is steamed at 60 ° C. using a steam setter.
Twist-prevention set for 30 minutes to make warp yarn, and this false-twisted yarn is subjected to 1000 T / m real twist in the S twist direction and 1000 T / m real twist in the Z twist direction to the weft yarn. A plain woven fabric was woven by alternately using the two yarns. It should be noted that no problem occurred in the process passability.

Subsequently, the greige is relaxed and refined (98 ° C., 3
0 minutes), set at 180 ° C., subjected to 15% alkali weight reduction processing, and subsequently dyed with a disperse dye (dye Dianix Brown 3B-FS, 2.25% owf) using a jet dyeing machine, Final set at 160 ° C. The resulting fabric had a large bulge and a supple and soft surface touch. (Comparative Example 1) Polyethylene terephthalate as a sheath yarn was melt-spun at a spinning speed of 3700 m / min and 110 dtex.
Highly oriented unstretched yarn of -48 filaments was spun by the usual melt spinning method. On the other hand, a polyester obtained by copolymerizing 8 mol% of isophthalic acid, 5 mol% of 2-2bis [4- (2-hydroxyethoxy) phenyl] propane, and 87 mol% in total of ethylene glycol and terephthalic acid as core yarns. The components were spun by an ordinary melt spinning method, and a highly shrinkable completely drawn yarn of 84 dtex-12 filament was obtained by an ordinary drawing method. The highly oriented undrawn yarn and the fully drawn yarn are divided into yarns by a triaxial friction disk false twisting machine shown in FIG. 4 so that the sheath yarns are over-supplied at a rate of 10% with respect to the core yarns. After that, false twisting was performed while twisting with a triaxial friction twister on an unheated primary heater, then 2% relaxation heat treatment was performed with a secondary heater, and the fibers were mixed by an interlace air nozzle and wound on a winder. .

The physical properties of the obtained composite textured yarn are as shown in Table 1. After 800 T / m of actual twisting, the same anti-twisting set as in the example is carried out to weave a plain woven fabric for the warp yarn and the weft yarn, and the same dyeing process as in the example 1 is performed. Got Although the bulge of the woven fabric was excellent, it had a rough and rough surface touch peculiar to false twisted yarn. (Comparative Example 2) Simultaneous spinning / blending of a round cross-section polyester yarn using polyethylene terephthalate and a round cross-section polyester in which polystyrene was compounded in the core portion at a weight ratio of 10.5% at the same spinner speed of 3200 m / min. And then 15
An unstretched mixed filament yarn of 0 dtex-45 filament (core yarn 75 dtex-9 filament, sheath yarn 75 dtex-36 filament) was obtained. This unstretched mixed filament yarn was used as in Example 1
After false twisting and stretching at a false twisting temperature of 130 ° with a shaft type friction disk false twisting machine, the fibers are mixed by an interlace air nozzle, and 84 dtex-45 filament (core yarn 42 dtex-9
A composite false twisted yarn of filament and sheath yarn 42dtex-36 filament) was obtained. The difference in yarn length of false twisted yarn is 10%,
After the boiling water treatment for 15 minutes and the dry heat treatment at 180 ° C. for 5 minutes, the yarn length difference was 14%. The same woven fabric as in Example 1 was prepared using this yarn, but the swelling feeling was poor.

[0035]

[Table 1]

[0036]

EFFECTS OF THE INVENTION The polyester composite false twisted yarn of the present invention exhibits a large yarn length difference due to heat received during dyeing, and has a small initial Young's modulus of the single filament of the sheath yarn and a relatively small elongation / expansion percentage. Thus, it is possible to impart a large bulge and a soft and supple surface touch to the woven or knitted fabric.

[Brief description of drawings]

FIG. 1 is a schematic process drawing showing an example of a method for producing a polyester composite false twisted yarn according to the present invention.

FIG. 2 is a schematic view showing an example of a polyester composite false twisted yarn according to the present invention.

FIG. 3 is a schematic view showing an example after the polyester composite false twisted yarn according to the present invention is treated with boiling water and subsequently subjected to dry heat treatment.

FIG. 4 is a schematic process drawing showing a method for producing a polyester composite false twisted yarn of Comparative Example 1.

[Explanation of symbols]

1: Polyester highly oriented undrawn yarn 2: Roller 1 3: Heater 4: Roller 2 5: 3-axis friction twister 6: Roller 3 7: Interlaced air nozzle 8: Roller 4 9: Winder A: Polyester multifilament A (core yarn) B: Core / sheath composite multifilament B (sheath yarn) 11: Polyester highly oriented undrawn yarn 12: Polyester stretched yarn 13: Roller 1 14: Roller 2 15: Roller 3 16: Primary heater 17: 3-axis friction twister 18: Roller 4 19: Secondary heater 20: Roller 5 21: Interlaced air nozzle 22: Winder

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Claims (5)

[Claims] 1. A composite false twisted yarn comprising a polyester multifilament A and a core / sheath type composite multifilament B in which polystyrene constitutes a core portion and polyester constitutes a sheath portion, wherein the polyester multifilament A is A core yarn is formed, and the polyester multifilament A and the core / sheath composite multifilament B are formed.
Is a polyester composite false-twisted yarn having the following relationships a to d. a. The difference in yarn length between the polyester multifilament A of the composite false twisted yarn and the core / sheath type composite multifilament B is less than 15% b. In the composite false-twisted yarn subjected to the dry heat treatment at 180 ° C. after the boiling water treatment, the yarn length difference between the polyester multifilament A and the core / sheath composite multifilament B is 15% or more and 35% or less c. The initial Young's modulus of the core / sheath type composite multifilament B is 10 cN / dtex or less d. Expansion and contraction rate of composite false twisted yarn is 20% or less 2. The polyester composite according to claim 1, wherein the polyester multifilament A has a single fiber fineness of 4.4 dtex or more and the core / sheath type composite multifilament B has a single fiber fineness of 1.5 dtex or less. False twisted yarn. 3. The polyester composite false twisted yarn according to claim 1, wherein the cross-sectional shape of the monofilament constituting the polyester multifilament A is a hollow cross section. 4. The polyester composite false twisted yarn according to claim 1, wherein the degree of entanglement is 20 yarns / m or more. 5. The polyester multifilament A comprises a copolyester.
4. The polyester composite false twisted yarn according to any one of 4 above.