JP2003082541A - Polyester false-twist textured yarn - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyester false-twist textured yarn giving woven/knitted fabrics which have good color clearness after dyed, drape property, soft feeling and puffy feeling and present touch feeling of new sense differing from fabrics comprising conventional drawn yarns or false-twist textured yarns. SOLUTION: This polyester false-twist textured yarn is made from a modified polyester copolymerized with 2.0-3.0 wt.% of sodium 5-sulfoisophthalate and 0.5-1.9 wt.% of a glycol component 400-6,000 in molecular weight and meets the properties (1) to (6) described below: (1) deformation degree of the constituent single filament is 1.0-2.0, (2) elongation at break is 20-50%, (3) percent crimp recovery (CR) is 10-40%, (4) percent elongation for crimp expression(TR) is 0.5-15%, (5) maximum shrinkage stress is 0.1-1.0 CN/dtex, and (6) interlace number is 4-50.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a crimped yarn,
False twisting with less cross-sectional deformation, excellent softness, swelling, drape, sharpness after dyeing, and a woven or knitted fabric with a new feel that is different from conventional stretched and false twisted yarns. Regarding yarn.

[0002]

2. Description of the Related Art Polyester fibers are widely used in various fields including general clothing because of their excellent properties such as mechanical properties. In clothing applications, the quality has been improved by targeting natural fibers, and in particular, in order to give the drawn yarn insufficient bulkiness, false twisting is performed at the same time as drawing, and a texture with a feeling of bulkiness has been obtained. However, when false twisting is applied, the feel of the woven or knitted fabric becomes unpleasant and the softness is insufficient, and the cross section is greatly deformed by false twisting, and the effect of the cross section is not utilized in the woven or knitted fabric. Also had. In addition, processing at high temperature is required to maintain sufficient bulkiness and crimp characteristics, and there is also a problem that the shrinkage rate is low.

Japanese Patent Laid-Open No. 1-314740 is known as a technique for widening the shrinkage level and reducing cross-sectional deformation. Further, Japanese Patent Application Laid-Open No. 1-183540 is known as a technique for using a highly shrinkable yarn to reduce cross-sectional deformation and to produce a high-density fabric. However, according to these two methods, since the false twisting is performed while heating at a temperature not higher than the glass transition point, the workability is deteriorated and it is not suitable for industrial production.

[0004]

DISCLOSURE OF THE INVENTION The object of the present invention is to improve the above-mentioned drawbacks of the prior art, and in a woven or knitted fabric (hereinafter referred to as “woven or knitted fabric”), softness, dyeability and stretchability. To provide an excellent polyester false twisted yarn.

[0005]

The above object of the present invention is to:
2.0-3.0 wt% 5-sodium sulfoisophthalic acid, 0.5-1.9 wt% molecular weight 400-6000
It can be achieved by using a polyester false twist textured yarn which is characterized by satisfying the following properties (1) to (6) consisting of a modified polyester obtained by copolymerizing a glycol component. (1) Deformation degree of constituent single yarn is 1.0 or more and 2.0 or less, (2) Elongation is 20% or more and 50% or less, (3) Stretch recovery rate (CR) is 10% or more and 40% or less, 4) Crimp expression elongation rate (TR) is 0.5% or more and 15% or less, (5) Maximum shrinkage stress value is 0.1CN / dtex or more 1.
0CN / dtex or less, (6) Confounding number is 4 or more and 50 or less.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in more detail below.

The false twisted yarn referred to in the present invention is 2.0 to 3.
0% by weight of 5-sodium sulfoisophthalic acid, 0.5
It is composed of a modified polyester obtained by copolymerizing a glycol component having a molecular weight of 400 to 6000 of 1.9% by weight. When the copolymerization amount of 5-sodium sulfoisophthalic acid is less than 2.0% by weight, satisfactory sharpness after dyeing cannot be obtained. If it exceeds 3.0% by weight, a thickening action is exhibited, and a polyester false twisted yarn satisfying the characteristics of the present invention that can be practically used cannot be obtained. It is preferably 1.5 to 2.8% by weight. If the molecular weight of the glycol component is less than 400, satisfactory sharpness after dyeing cannot be obtained. If it exceeds 6000, the oxidative degradability of the copolymerized polymer deteriorates. Preferably 400-2
It is 000. If the copolymerization amount of the glycol component is less than 0.5% by weight, the effect of improving the sharpness after dyeing is small, and if it exceeds 1.9% by weight, the light fastness of the dyed product is deteriorated. It is preferably 0.7 to 1.5% by weight. The polyester false twist textured yarn in the present invention has a single yarn deformation degree of 1.0 or more.2.
It is 0 or less. It is preferably 1.0 or more and 1.7 or less, and more preferably 1.0 or more and 1.5 or less. When the degree of deformation exceeds 2.0, the advantage of the cross-sectional shape of the raw yarn is lost. The cross-sectional shape of the single yarn constituting the polyester false twisted yarn may be circular or modified, and may be mixed. The characteristic of the raw yarn is utilized because the deformation after processing is small. The cross-sectional deformation degree referred to here is calculated by the following equation. (Fig. 3
Deformation degree = Length of longest part of single yarn cross section (long axis)
(A in FIG. 3) / maximum width of the cross section of the single yarn with respect to the major axis (B in FIG. 3) From the point of slight deformation, flicker is prevented and a mild gloss is obtained. Further, the effect is further exerted in combination with the sharpness provided by the modified polyester.

The false twisted polyester yarn in the present invention has an elongation of 20% or more and 50% or less. If the elongation is less than 20%, fluff occurs and the processability such as weaving becomes poor. Further, if the elongation exceeds 50%, the orientation becomes insufficient and the strength becomes insufficient. If you want to emphasize the softness, it is preferably 23% or more and 40% or less,
More preferably, it is 25% or more and 40% or less.

The polyester false twist textured yarn in the present invention has a stretch recovery rate (CR) of 10% or more and 40% or less, preferably 12% or more and 35% or less, and more preferably 12% or more and 33%. It is the following. CR is 10
When it is less than%, the expansion and contraction after weaving or knitting is small and the bulging feeling of the woven or knitted fabric is reduced. Also, CR is 40
If it exceeds%, the expansion and contraction after the dyeing and finishing process becomes large, and the structure of the woven or knitted fabric is greatly changed, resulting in poor softness.

The expansion and contraction recovery rate (CR) is JIS L
It was obtained by measuring with 1019T by the measuring method described later. Further, the false twist textured yarn in the present invention is
The crimp expression elongation rate (TR) is 0.5% or more and 15% or less, preferably 0.6% or more and 10% or less, and more preferably 0.6% or more and 0.8% or less. Is. When the crimp development elongation rate (TR) exceeds 15%, the crimp development after dyeing and finishing of the woven or knitted fabric becomes large, and the softness of the woven or knitted fabric is deteriorated.

The crimp development elongation rate (TR) is obtained by the measuring method described later.

The polyester false twist textured yarn in the present invention has a maximum shrinkage stress value of 0.1 cN / dtex or more and 1.0 cN / dtex or less, preferably 0.1 cN / dtex or more and 0.5 cN / dtex or less, and more preferably 0.1 cN / dtex or more and 0.3 cN / dtex or less. When the maximum shrinkage stress value exceeds 1.0 cN / dtex, the shrinkage of the dyed finished fabric becomes large and the softness of the woven or knitted fabric is impaired.

The maximum shrinkage stress value is obtained by the method described below.

The polyester false twisted yarn in the present invention has a low crimp and therefore has an entanglement number of 4 or more and 50 or less, preferably 5 or more and 45 or less, and more preferably 6 or more and 40 or less. It is the following. When the number of entanglements exceeds 50, the entangled portions remain even after the dyeing and finishing step, so that the product quality deteriorates, and when the number is less than 4, the unwinding property decreases during the twisting step and the feeding to the loom, and the productivity decreases.

The confounding number is obtained by the method described later.

The polyester false twisted yarn in the present invention preferably has a real twist of 4 t / m or more and 15 t / m. More preferably, 4 or more and 14 t / m
It is below, and 4 t / m or more and 13 t / m or less are the most preferable. This is because the entanglement between the single yarns and the convergence of the multifilaments occur, but if the actual twist exceeds 15 t / m, the movement of the single yarns becomes insufficient after the dyeing and finishing process, resulting in lack of softness.

The false twisted yarn described above can be obtained by the following method. That is, a twist stopper provided at a position between the heating body and the false twist tool, which is different from the point that the yarn is separated from the heating body after the undrawn yarn of the synthetic fiber is heated by the heating body before twisting. Is used as the starting point for twisting, and the drawing false twisting process is continuously performed.

A more specific description will be given based on an embodiment shown in the drawings.

FIG. 1 is a process drawing showing an example of a method for producing a polyester false twist textured yarn of the present invention. In FIG. 1, an undrawn yarn 1 from a modified polyester is wound around a heating roll 3 and a separate roll 4 through a feed roll 2 and preheated, and a twisting prevention device 6, a false twisting tool 7, and a heatable take-up roller are provided. Stretching false twisting is continuously performed by using the twist stopping device 6 provided at a point different from the point 5 where the heating roll 3 and the yarn separate from each other between 8 and 8 as a heating start point. Then, after passing through the unheated stretch roll 9, it is wound up as a pan 10 using a spindle type winding device. The drawing false twist continuous processing of the present invention may be the above-mentioned indrow method or the outdraw method.

According to the above method of the present invention, since the twist fixing is performed by the heat received by the yarn from the heating body, the twist fixing force is small. Therefore, the polyester false twisted yarn obtained by the present invention does not have a high crimping property such as the conventional false twisted yarn due to the deterioration of drapeability, swelling feeling, and softness in the fabric, and a woven or knitted fabric. When it is applied, the drape property is good, and the swelling feeling, soft feeling, and sharpness after dyeing are excellent,
It is possible to exhibit a new feel that is different from the conventional drawn yarn and false twisted yarn. Further, unlike the conventional false twisting method, since the yarn is heated in a non-twisted state, it is possible to apply a uniform and sufficient amount of heat to all the single yarns in the yarn. Furthermore, since the twisting device provided at a position different from the point where the yarns on the heating element are separated is used as the twisting start point, the twisting back to the heating element can be prevented, and fluff and yarn breakage do not occur.

The drawn false-twisting method of the present invention is excellent in processing stability and quality uniformity because the drawn false-twisting process is carried out at the glass transition point or higher. The temperature of the heating roll 3 may be appropriately set according to the type of synthetic fiber yarn to be used, desired crimping performance, processing speed, etc. It is preferably at least the glass transition temperature of the strip. Further, the number of windings around the heating roll 3 may be appropriately set according to a desired heat quantity, but it is preferably 4 or more in order to prevent the yarn from slipping. If the take-up roll 8 is a roll that can be heated similarly to the heating roll 3, the false twisted yarn can be heat set, and the two-stage heater false twisted yarn can be easily manufactured. Moreover, since the temperature of the take-up roll 8 can be arbitrarily selected, the boiling water shrinkage can be made higher than that of the conventional false twisted yarn.

The anti-twisting device 6 provided at the twisting start point is a device which has an effect of preventing the twisting back to the heating roll 3, so long as it is a non-rotating guide such as a bar guide or a roller guide that has been conventionally used. Rotation guides such as can be arbitrarily selected.

As the false twisting tool 7, a false twisting tool such as a pin system or a triaxial friction type disk system can be arbitrarily adopted, but a temporary twisting system such as a triaxial friction type disk system or a belt nip system which can increase the processing speed can be adopted. It is preferable to use a twisting device.

Twisted and untwisted, take-up roll 8,
The false twisted yarn taken up by the stretch roll 9 is taken up as a pan 10 by using a spindle type take-up device. Winding the polyester false twisted yarn of the present invention in a pan shape using a spindle type winding device,
The false twisted yarn of the present invention can be actually twisted, and the untwistability can be improved during the twisting process and supply to the loom, which is preferable. Further, in order to improve the unwinding property of the false twisted yarn, an air entanglement nozzle (not shown) may be provided between the stretch roll 9 and the separate roll, and entanglement may be imparted using the air entanglement nozzle. More preferable.

By additionally twisting the false twisted yarn of the present invention having an optimized shrinkage rate of boiling water, and then heat shrinking the twisted yarn, the number of twists per unit can be increased and elasticity can be imparted by the spring effect. . The number of additional twists can be set as appropriate, but the range of 100 t / m or more and 2000 t / m or less that is generally used is preferable. The undrawn yarn used here has a spinning speed of 2000 m.
It is preferably wound at a rate of not less than / min and not more than 5000 m / min. If it is less than 2000 m / min, it is disadvantageous in increasing the false twisting speed, and if it exceeds 5000 m / min, yarn breakage and fuzz during false twisting increase.

The number of false twists of the false twist tool can be set appropriately, but is 15
The range of 00 or more and 4500 t / m or less is preferable. The drawing false twisting speed can be set appropriately, but 400 m / min or more 1
A range of 500 m / min is preferred.

[0027]

EXAMPLES The present invention will be described in more detail with reference to Examples and Comparative Examples of the present invention. In addition, the following methods were used for the evaluation methods and measurement methods in the examples. The evaluation results and the measurement results are shown in Tables 1 and 2.

A. Degree of deformation of single yarn The deformation degree of the single yarn is calculated by the following formula.

Deformation degree = long axis of single yarn cross section (A in FIG. 4) / maximum width of single yarn cross section with respect to long axis (B in FIG. 4) B. Expansion and recovery rate (referred to as CR (%).) Initial tension using a measuring machine: (0.088 x fineness (dte
x)) With cN, a skein having a length of 50 cm and a winding number of 10 is made, immersed in hot water of 90 ° C. for 20 minutes, drained with absorbent paper or a cloth, and naturally dried in a horizontal state. The skein roll is placed in water at room temperature, and the sample length: a is measured with a specified initial load and a constant load applied. Next, the constant load is removed, and the sample is left in water with only the initial load applied for 3 minutes, the sample length after 3 minutes: b is measured, and the expansion / contraction recovery rate CR (%) is calculated by the following formula. . For the initial load and constant load, use those obtained by the following formula.

CR (%) = ((ab) / a) × 100 Initial load (cN) = (Fineness (dtex) /1.111) ×
0.002 × 0.9807 × number of windings × 2 constant load (cN) = (fineness (dtex) /1.111) ×
0.1 × 0.9807 × number of windings × 2 C.I. Crimping elongation rate (referred to as TR (%).) Initial tension using a measuring machine: (0.088 x fineness (dte
x)) A skein having a length of 50 cm and a winding number of 20 is made with cN, an initial load is applied, and a dry heat treatment is performed at 150 ± 2 ° C. for 5 minutes. After the dry heat treatment, the sample length: a in the state where the initial load is applied is measured. Next, the initial load is removed and the sample length: b is measured with a constant load applied.
Calculate (%). For the initial load and constant load, use those obtained by the following formula.

TR (%) = ((b−a) / b) × 100 Initial load (cN) = (Fineness (dtex) /1.111) ×
0.00166 x 0.9807 x number of windings x 2 constant load (cN) = (fineness (dtex) /1.111) x
0.1 x 0.9807 x number of windings x 2 D. Maximum shrinkage stress value Kanebo Engineering thermal stress measuring instrument (type K
E-2S), and the sample in the form of a string was 0.088 cN /
After the initial load of dtex was applied, the temperature was raised at a rate of 2.5 ° C./sec, and the generated stress was recorded on the chart. The maximum shrinkage stress value was represented by cN / dtex by dividing the maximum shrinkage stress read from the chart by the fineness.

E. Confounding number According to the regulation of JIS-L1013 (1992), the insultment tester (model: R204 manufactured by Roschild Co., Ltd.
0) is used for measurement.

F. The false twisted textured yarns obtained in the fabric evaluation examples and the comparative examples were made to have a length of 35 by means of a one-piece tubular knitting machine (gauge number: 20) manufactured by Koike Machinery Mfg. Co., Ltd.
Cylinder knitting of cm was prepared, and dyeing, washing with water and drying were performed by a conventional method using a Pro-Compaddle automatic dyeing machine. With respect to the fabric obtained by the above method, swelling feeling, softness, and sharpness after dyeing were sensory-evaluated in 1 to 5 grades, and grades 3 or higher were passed.

Further, plain weaving was performed by using the polyester flat yarn of 33 dtex12 filament as a warp and the false twist textured yarn obtained in Examples and Comparative Examples as a weft. The drape property of the cloth obtained by this method is 1 to 5
The sensory evaluation was carried out according to the grade, and the grade 3 or higher was passed.

G. False twisting property Using 500 undrawn yarns, the ratio of false twisting yarns in which no yarn breakage or fluff did not occur when obtaining a false twisting yarn of 3.0 kg was taken as false twisting processability (%). , 99.0% or more was accepted.

H. Number of fuzz generated MULTI POINT FLAY COU manufactured by Toray Engineering Co., Ltd.
While running at a yarn speed of 400 m / min with NTER model MFC-1110, the number of fluffs was measured for 5 minutes, and the average value of 50 fluffs was taken as the number of fluffs generated. Number of fluffs generated is 0.50 /
Less than 2000m was qualified.

Example 1 2.6% by weight of 5-sodium sulfoisophthalic acid was added, and transesterification reaction was carried out from terephthalic acid and ethylene glycol using antimony trioxide as a polymerization catalyst. Was added to cause polycondensation reaction to obtain polyethylene terephthalate (PET) having an intrinsic viscosity of 0.69 (measured in an oxochlorophenol solvent at 25 ° C.). The obtained polymer was melt-spun at a spinning temperature of 290 ° C. and a spinning speed of 3000 m / min, and an undrawn yarn (POY) of 134.0 dtex and 36 filaments was wound. Using the drawing false twisting continuous processing apparatus shown in FIG. 1, the POY is twisted with the heating roll 3 at a temperature of 100 ° C., the take-up roll 8 at a room temperature, a draw ratio of 1.55 times, and a drawing speed of 820 m / min. A rotating roller guide is used for the device 7, and a triaxial friction type disk type false twisting device is used for the false twisting tool 8.
At 0 rpm, an air entanglement nozzle was used between the take-up roll 8 and the stretch roll 9, and the pneumatic pressure was 0.29.
Entangling was applied at 4 MPa, and a 3.0 kg wound pan was wound by a spindle type winding device to obtain 84.0 dte.
A false twist textured yarn of x, 36 filaments was obtained. The obtained false twisted yarn has a degree of deformation of 1.30, an elongation of 38%, a CR of 27%, a TR of 4.2%, and a maximum shrinkage stress value of 0.23c.
N / dtex, the number of entanglements was 36, and the number of actual twists was 11 t / m. As for the evaluation of the cloth, the sharpness, the swelling feeling, the soft feeling, and the drape property were all 5th grade, and a very excellent cloth was obtained. In the continuous drawing false twisting process under the above-mentioned conditions, retrospective twisting to the heating roll does not occur, and the false twisting processability is 99.
The fluff was 8%, and no fluff was observed in the obtained bun, and the number of fluffs generated was 0/2000 m.

Example 2 A yarn was produced under the same conditions as in Example 1 except that the draw ratio was 1.60. The obtained false twisted yarn has a degree of deformation of 1.40, an elongation of 34%, a CR of 29%, and a TR of 5.1.
%, The maximum shrinkage stress value was 0.25 cN / dtex, and the entanglement number was 31. As for the fabric evaluation, a soft fabric, a drape property of the fourth grade, a swelling feel, and a sharpness after dyeing of the fifth grade were obtained, and a good fabric rich in the swelling feel was obtained. In the continuous drawing false twisting process under the above-mentioned conditions, the retrograde twisting to the heating roll did not occur, the false twisting processability was also good at 99.4%, and no fluff was observed in the obtained pan, and fluff occurred. The number was 0.06 / 2000 m.

Example 3 Spinning was performed under the same conditions as in Example 1 except that the temperature of the heating roll 3 was 110 ° C. The obtained false twisted yarn has a deformation degree of 1.70, an elongation of 39%, a CR of 34%, a TR of 4.0%, a maximum shrinkage stress value of 0.24 cN / dtex,
The number of confounding was 36. As for the fabric evaluation, a soft fabric, a drape property of the fourth grade, a swelling feel, and a sharpness after dyeing of the fifth grade were obtained, and a good fabric rich in the swelling feel was obtained. In the continuous drawing false twisting process under the above-mentioned conditions, the twisting back to the heating roll did not occur, the false twisting processability was 99.5%, and no fluff was observed in the obtained pan. The number was 0.02 pieces / 2000 m.

Example 4 The false twisted yarn obtained in Example 1 was subjected to additional twisting of 1000 t / m, the twisted yarn was used as a weft, and a polyester flat yarn of 33 dtex 6 filaments was used as a warp to prepare a plain weave. It was dyed and finished. With respect to the fabric obtained by this method, the sharpness and stretchability after dyeing were sensory-evaluated in 1 to 5 grades, and grades 3 or higher were passed. The obtained fabric had grade 5 of sharpness and stretchability after dyeing, and was a fabric having excellent sharpness and stretchability.

Comparative Example 1 Using antimony trioxide as a polymerization catalyst, polyethylene terephthalate (PET) having an intrinsic viscosity of 0.65 (measured at 25 ° C. in an oxochlorophenol solvent) was obtained from terephthalic acid and ethylene glycol according to a conventional method. It was At this time, 0.4% wt% of titanium oxide having an average primary particle size of 0.5 μm was added as a matting agent. The obtained polymer was melt-spun at a spinning temperature of 284 ° C. and a spinning speed of 3000 m / min, and an undrawn yarn (POY) of 134.0 dtex and 36 filaments was wound. The POY is heated at a temperature of the heating roll 3 of 100 using the drawing false twisting continuous processing device of FIG.
C, the temperature of the take-up roll 8 is room temperature, and the draw ratio is 1.6
0 times, stretching speed 820m / min, twist prevention device 7
A rotary roller guide and a false twisting tool 8 using a triaxial friction type disk false twisting device, and the disc rotation speed is 6650 rpm.
As an example, an air confounding nozzle is used between the take-up roll 8 and the stretch roll 9, and the pneumatic pressure is 0.294 MPa.
As a entanglement, and it is 3.0 by the spindle type winding device.
Winding a kg roll, 84.0 dtex, 36
A false twisted yarn of filament was obtained. The obtained false twisted yarn has an elongation of 40%, a CR of 32%, a TR of 5.2%, a maximum shrinkage stress value of 0.13 cN / dtex and an entanglement number of 35.
Met. As for the evaluation of the fabric, the swelling feeling, the soft feeling, and the drape property were all grade 5, and a very excellent cloth was obtained. In the continuous drawing false twisting process under the above-mentioned conditions, the retrograde twisting to the heating roll does not occur, and the false twisting processability is 99.8.
%, And no fluff was observed in the obtained bun, and the number of fluffs generated was 0/2000 m. However, the sharpness after dyeing was grade 2.

Comparative Example 2 The modified polyethylene terephthalate undrawn yarn 20 obtained by the same method as in Example 1 was used in the conventional false twisting apparatus shown in FIG. Simultaneous drawing false twisting was performed at 1.70 times, a processing speed of 630 m / min, and a disk rotational speed of the false twisting tool 24 of 7500 rpm to obtain a false twisted textured yarn of 86.9 dtex 36 filaments. The obtained false twisted yarn has a deformation degree of 3.00, an elongation of 18%, a CR of 42%, a TR of 30.0%, a maximum shrinkage stress value of 0.20 cN / dtex and an entanglement number of 80. there were. The false twisted yarn has a high degree of crimpability, and therefore, in the fabric evaluation, the sharpness after dyeing was grade 5, but the swelling and soft feelings were lacking, and the drapeability was also poor. there were. Comparative Example 3 A false twisted yarn was obtained in the same manner as in Example 1 except that the twisting prevention device 6 was not provided between the heating roll 3 and the false twisting tool 7. ,
When an attempt was made to obtain the same amount of false twisted yarn as in Example 1, a yarn breakage occurred at the time of inserting the yarn into the false twisting tool 7, and the false twisted yarn could not be obtained.

Comparative Example 4 The false twisted yarn obtained in Comparative Example 2 was subjected to additional twisting of 1000 t / m, the twisted yarn was used as a weft, and the polyester flat yarn of 33 dtex6 filament was used as a warp to prepare a plain weave, and the conditions normally used. It was dyed and finished. The fabric obtained by the method was subjected to a sensory evaluation of stretchability in grades 1 to 5, and 3
Passed the grade and above. The obtained fabric has a sharpness of grade 5,
The stretchability was grade 2, and the fabric was inferior in stretchability.

[0044]

[Table 1]

[0045]

[Table 2]

[0046]

EFFECTS OF THE INVENTION By using the polyester false twisted yarn of the present invention, it has excellent sharpness after dyeing, has good drapeability, is excellent in softness and swelling, and has a conventional drawn yarn and false twisted texture. It is possible to provide a woven / knitted fabric having a new feeling different from that of the yarn.

[Brief description of drawings]

FIG. 1 is a process drawing showing an example of a method for producing a polyester false twist textured yarn of the present invention.

FIG. 2 is a schematic view showing an example of a conventional false twisting process.

FIG. 3 is a single yarn cross-sectional view showing an example of the degree of cross-sectional deformation of the single yarn of the present invention.

[Explanation of symbols]

1: Undrawn yarn 2: Feed roll 3: Heating roll 4: Separate roll 5: The point where the heating roll and the yarn separate 6: Twist stop device 7: False twisting tool 8: Collection roll 9: Stretch roll 10: Pan 20: Undrawn yarn 21: Thread unwinding guide 22: Supply roll 23: False twist heater 24: False twisting tool 25: Take-up roller 26: Second take-up roller 27: False twist cheese A: Length of the longest part of the single yarn cross section (long axis) B: Maximum width of the single yarn cross section with respect to the major axis

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 4L036 MA05 MA26 MA33 PA14 PA21                       PA42

Claims (3)

[Claims] 1. 2.0 to 3.0% by weight of 5-sodium sulfoisophthalic acid, 0.5 to 1.9% by weight of molecular weight 40.
A polyester false twisted yarn, characterized by satisfying the following properties (1) to (6), which is composed of a modified polyester obtained by copolymerizing a glycol component of 0 to 6000. (1) Deformation degree of constituent single yarn is 1.0 or more and 2.0 or less, (2) Elongation is 20% or more and 50% or less, (3) Stretch recovery rate (CR) is 10% or more and 40% or less, 4) Crimp expression elongation rate (TR) is 0.5% or more and 15% or less, (5) Maximum shrinkage stress value is 0.1CN / dtex or more 1.
0CN / dtex or less, (6) Confounding number is 4 or more and 50 or less. 2. The polyester false twisted yarn according to claim 1, which has a real twist of 4 t / m or more and 15 t / m or less. 3. A twist stopper provided at a position between the heating body and the false twisting tool, which is different from the point that the yarn is separated from the heating body after the undrawn yarn is heated by the heating body before twisting. 3. The polyester false twisted yarn according to claim 1 or 2, which is obtained by continuously performing a drawing false twisting process using as a twisting start point.