JPH0987966A - Woven or knitted fabric and its production - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a woven or knitted fabric provided with a touch excellent in a dry touch, a refreshing touch, etc., without deteriorating the original lightweight property of the woven or knitted fabric using hollow fibers. SOLUTION: Multifilament yarns comprising plural modified cross-sectional hollow filaments 10 having each an irregularly deformed tetragonal outer shape on the cross section and a hollow part continued in the longitudinal direction, wherein the modified tetragons are mutually varied among the filaments 10, 10, are used as weaving or knitting yarns to produce the woven or knitted fabric. Conjugate multifilament hollow yarns comprising each a homopolyester core component having a hollow part which is tetragonal on the cross section and continued in the longitudinal direction and a copolyester sheath component capable of being more easily dissolved in an alkaline solution than the homopolyester are really twisted and subsequently subjected to a false-twisting treatment, or subjected to the false-twisting treatment and subsequently really twisted. The false-twisted yarns are processed into the woven or knitted fabric, which is treated with an alkali to dissolve out the sheath components of the conjugate filament yarns.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a woven or knitted product made of hollow fibers and a method for producing the same.

[0002]

2. Description of the Related Art Hollow fibers are superior in lightness and swelling feeling to non-hollow fibers, and their features can be made more remarkable as the hollow ratio increases, and they also have high resilience and thus have resilience. It is known to show a texture. In particular, when the hollow fiber is made of polyester, the repulsive texture can be made more remarkable due to the high crystallinity inherent in polyester.

However, in a woven or knitted fabric using merely hollow fibers,
It has a strong slimy feel like ordinary synthetic fibers, which is an obstacle to its wide-ranging applications such as high-quality clothes. Conventionally, as a measure against such a slimy feeling,
There is a proposal to reduce the area where the yarn surface comes into contact with the skin to eliminate the slimy feeling and dry feeling by false twisting the original yarn or by melt-spinning the original yarn as a polygonal cross-section yarn. However, in the former method of false twisting, if this is simply applied to the hollow fiber, the hollow part is completely crushed, and as a result, the features such as the lightweight feeling originally possessed by the hollow fiber are lost. There is a drawback that it ends up.

Further, in the method of forming a yarn having a polygonal cross section, a sharp edge cannot be formed because the molten polymer spun from the spinneret hole has a phenomenon in which the thread cross section tends to be circular due to surface tension. As a result, there is a drawback that a high-quality dry feeling and a refreshing feeling cannot be obtained.
Also, when woven and knitted fabrics using hollow fibers are used repeatedly,
Eventually, the surface of the hollow fiber is rubbed, and the part surrounding the hollow part is torn or broken to form fibrils, and a so-called "frosting" whitening phenomenon becomes apparent. In particular, a hollow fiber having a polygonal cross section such as a triangular shape to a hexagonal shape has a defect that frosting easily occurs.

As a method of suppressing such frosting, (1) a method of using a hollow fiber having a relatively small hollow ratio, (2) a single yarn having a circular or elliptical cross section is applied from the outside. There is a method to spread the load of frictional force as much as possible on the whole noodles. However, the former method has the drawback that the lightness and swelling characteristic of hollow fibers are impaired,
In addition, the latter method has a drawback that a refreshing feeling and a dry feeling cannot be obtained and a slimy feeling is obtained.

[0006]

SUMMARY OF THE INVENTION The object of the present invention is to provide an excellent dry feeling and a refreshing feeling without impairing the lightness and the swelling feeling originally possessed by a woven or knitted fabric using hollow fibers, and to prevent the whitening phenomenon. It is an object of the present invention to provide a woven / knitted fabric having an anti-frosting property that hardly occurs and a method for producing the same.

[0007]

The woven and knitted fabric according to the present invention for solving the above-mentioned object has a deformed quadrilateral whose outer cross-section is irregularly squashed and which is substantially continuous in the axial direction of the filament. A multifilament yarn composed of a plurality of modified cross-section hollow filaments each having different shapes, and the modified quadrilateral being variously different from each other among the plurality of modified cross-section hollow filaments, as a woven or knitting yarn. It is characterized by.

More preferably, the deformed quadrilateral forming the outer shape may have at least two or more portions having an acute angle at an intersecting edge of adjacent sides. Further, in the method for producing a woven or knitted material according to the present invention, the outer shape in the transverse cross section is substantially quadrilateral, and the core component made of polyester having a hollow portion continuous in the filament axial direction is more easily dissolved by alkali than the polyester. A false twisted yarn is obtained by applying a false twist to a multifilament yarn made of a composite filament fiber made of a sheath component made of a copolyester and then performing a false twist process or a false twist process and then a true twist process. Then, the false twisted yarn is used as a woven or knitted yarn to form a woven or knitted product, and then the woven or knitted product is treated with an alkali to elute the sheath component of the composite filament fiber.

[0009]

BEST MODE FOR CARRYING OUT THE INVENTION The woven or knitting yarn of the hollow fiber used in the woven or knitted fabric of the present invention is a deformed quadrilateral whose outer shape in a transverse cross section of a single yarn is irregular, and which is continuous in the axial direction of the yarn. It consists of a multifilament yarn with parts. Moreover,
The modified quadrilateral morphology of each hollow filament is made to be different in various ways among the hollow filaments. The multifilament yarn having such characteristics is
It is in the form of a processed yarn such as a strongly twisted yarn, a false twisted yarn, a pretwisted false twisted yarn, and a false twisted posttwisted yarn, and a pretwisted falsetwisted yarn or a false twisted twisted yarn is particularly preferable.

1 to 4 are cross-sectional views of hollow filaments used as the above-mentioned woven and knitting yarns, respectively. In any of the hollow filaments 10 shown in FIGS. 1 to 4, the outer shape of the polymer portion 1 forming the filament and the hollow portion 3 inside the polymer portion 1 are formed.
Although and are essentially quadrilaterals, all of them are squashed and deformed irregularly. As a multifilament yarn constituting a woven or knitting yarn, the cross section of the modified quadrilateral of the hollow filament 10 is variously different among the filaments.

The substantially quadrilateral cross-sectional shape of the hollow filament 10 is curved or bent by bending by an external force such as crushing, and the curved or bent side is concave inward in the cross-section. Many things are becoming. The edge e formed between two adjacent sides has a sharp acute angle in at least two places.

A woven or knitted fabric made of hollow multifilament yarn having a deformed quadrilateral with a cross section in this manner has the original lightness of the hollow fiber, and also has a deformed quadrilateral with a recessed cross section. Sting is improved. Further, the woven or knitting yarn of the hollow multifilament yarn has a plurality of sharp-edged sharp edges on the outer circumference and has curved or bent sides from the outer shape, so that the contact area with the skin is reduced, and thereby the fine dry The feeling and the refreshing feeling of dryness are further emphasized. In addition, the cross section has a modified quadrilateral and has sharp edges, which creates a crease like silk shift,
It gives a sense of luxury.

In the present invention, an example of a method for producing the above-mentioned woven or knitted material will be described. A core component made of polyester having a hollow portion which is substantially quadrangular in cross section and which is continuous in the filament axial direction, A multifilament yarn composed of a composite filament fiber composed of a sheath component composed of a copolymerized polyester which is more easily dissolved in an alkali than the core component polyester is used as a raw yarn. Such a core-sheath type composite filament fiber is given a real twist and then false twisted, or is false twisted and then subjected to a real twist to obtain a false twisted yarn.

Next, the false twisted yarn is used as a woven or knitted yarn to form a woven or knitted product. Further, this woven or knitted material is subjected to an alkali treatment to elute the sheath component (copolymerized polyester) of the composite filament fiber constituting the woven or knitted yarn. Here, the core component of the composite filament fiber left in the woven or knitted fabric is a modified quadrangular hollow multifilament yarn with a transverse cross section.

As described above, the force for relaxing the cross section of the composite filament fiber is generated based on the tightening force between the constituent filaments generated by twisting the composite multifilament yarn. When the filament is unraveled by such a tightening force, when one filament is viewed in the longitudinal direction, the unraveled random shape in the transverse section is also randomly obtained in the longitudinal direction and is not constant. Will contribute.

In the manufacturing method of the present invention, as the composite filament fiber before weaving or knitting into a woven or knitted product, one having a cross section as shown in FIGS. 5 to 8 is used. That is, as shown in FIGS. 5 to 8, the composite filament fiber 20 has a core component composed of a polymer portion 1 and a hollow portion 3 of polyester which are formed in a substantially quadrilateral shape, and the outer periphery thereof has a substantially circular cross-section. 5 to 7) or an oval (FIG. 8) copolyester polymer part 2 is configured to cover as a sheath component.

The polyester used as the core component here is a homopolymer, especially polyethylene terephthalate,
Homopolymers such as polybutylene terephthalate are preferred. On the other hand, as the copolyester used for the sheath component, a part of dicarboxylic acid or diol which is a constituent component of polyethylene terephthalate, polybutylene terephthalate or the like is replaced with another component such as sodium sulfoisophthalic acid or polyethylene glycol. The obtained copolymer is preferably used. This copolyester is characterized by a higher dissolution rate by alkali treatment than a polyester homopolymer.

Since the core-sheath structure composite filament fiber is spun in a state where the core component of the quadrilateral cross section is wrapped with the sheath component of which the melt viscosity is similar at the time of the melt spinning, the core component of the quadrilateral cross-section is surface tension. It keeps the edges of the quadrangle without circularization. Therefore, it is possible to obtain a hollow filament of a core component having a sharp edge when the sheath component is eluted in a subsequent step.

Further, since the sheath component of the above-mentioned composite filament fiber has a circular cross section, the compression action when false-twisting this can be applied almost evenly to the periphery of the composite filament fiber, and a partial local Can be prevented from joining. Therefore, the hollow portion is not completely crushed, and the characteristics of the hollow fiber can be maintained. When false-twisting a multifilament yarn composed of the above-mentioned composite filament fibers, a true twist is applied before or after the false-twisting. As described above, by adding the actual twist before or after the false twisting process, the woven or knitted yarn can be made to have a bundling property, and the woven or knitted product can exhibit a moderate bulging feeling. In the false twisting process, a twisting action exerts a compressive action on the constituent filaments of the multifilament yarn substantially in the cross-sectional direction, whereby a clamping force between the constituent filaments is generated and the filaments are crushed. Will be done.

Further, in the present invention, the false twisting temperature and the false twist number in the false twisting are set to be sweeter than the conditions generally adopted in the conventional false twisting. By setting such a sweet condition, the hollow part is not completely crushed, and it is held so as to be continuous in the filament axial direction, and the cross section is squashed to create a hollow filament with sharp edges emphasized. Obtainable.

The false twisting temperature which is sweeter than the general conditions is 130 ° C. or higher and 180 ° C. or lower, and the false twist number is the false twist number T (twice / twist given by the following equation.
m) is preferably 50 to 100%, more preferably 50 to 90%. T = (3.16 × 10 ⁴ /√D)×0.94 where D is the total fineness of the multifilament yarn (denier) The woven or knitted product which is woven or knitted with the above-mentioned woven or knitting yarn made of the composite filament fiber. The form is not particularly limited, but a plain woven fabric and a twilled woven fabric are preferable as the one that easily exhibits the lightweight feeling and the refreshing feeling of the hollow fiber. Further, in the case of a thin fabric, a strong twist georgette, amundsen, and desirkulep are preferably used, and in the case of a thick fabric, twill, variable twill, and satin weave are preferably used. In the case of a knitted fabric, smooth and mock Milano lipto are preferably used.

All of the woven and knitting yarns (1
It is desirable to use a hollow fiber for 100%), but if a mixed fiber of a hollow fiber and a non-hollow fiber is used, a firm and firm texture can be obtained. However, when non-hollow fibers are used in combination, the hollow fibers should be positioned at least on the surface layer of the woven or knitted fabric, and therefore the non-hollow fibers are used as the core and the hollow fibers are used as the sheath. It is desirable to use it as a composite mixed yarn. In this case, the hollow fiber mixing ratio is 5
It may be 0% by weight or more, preferably 80% by weight or more.

The alkali treatment of the woven or knitted fabric may be performed with an aqueous solution of caustic soda. By this alkaline treatment, the sheath component of the composite filament fiber constituting the woven or knitting yarn is eluted and removed, but the removal does not necessarily have to be the entire removal,
A small amount may remain. When a small amount of sheath component remains, a large number of shallow transverse grooves that intersect the filament axis are formed on the sheath component surface on the side of the modified quadrilateral cross section, further emphasizing a delicate dry feeling and a smooth refreshing feeling. become able to.

The woven and knitted fabric after the sheath component has been dissolved and removed in this way has an excellent dry feel, a refreshing feel and an anti-prosting property based on the above-mentioned deformed quadrangular cross section, and also depends on the reduction of the sheath component. Due to the formation of voids, a soft swelling feeling is increased, and a highly repulsive texture and light weight are improved.
Furthermore, the void formation due to the reduction of the sheath component also improves the water absorption and heat retention of the woven or knitted fabric.

In the present invention, in the woven or knitted fabric finally obtained after the alkali treatment, the hollow ratio which the hollow fibers constituting the woven or knitted yarn should have is preferably in the range of 10 to 50. With such a hollow ratio, the lightness of the hollow fiber can be maintained, and good anti-frosting property can be maintained.

[0026]

EXAMPLES Next, examples of the present invention will be described together with comparative examples. The characteristics used in the following examples and comparative examples were measured and evaluated as follows. (Texture) a. Dry feeling The woven and knitted fabric was touched by hand, and a dry delicate texture without a slimy feeling was made good, and a sensory evaluation was performed on the following four levels.

◎ Very good ○ Good △ Somewhat good × Bad b. Refreshing Feeling The woven and knitted fabric was touched with the hand, and the dry feel was taken as the refreshing feel, and sensory evaluation was performed in the order of the dry feel, in the order of the dry feel.

C. Softness and supple texture were evaluated as good, and sensory evaluation was carried out in four levels similar to dry feeling. d. Swelling feeling The thickness (mm) of the woven or knitted fabric is measured with a peacock thickness gauge (manufactured by Ozaki Seisakusho Co., Ltd.), and the thickness is weighted (g /
The value divided by m ² ) was expressed in the unit of “cc / g” and used as a standard for the feeling of bulging. It means that a woven or knitted fabric having a larger unit has a swelling feeling.

E. A feeling of squeaky When the cloths are rubbed against each other with fingers, the creaks and creases of the silk sound make the crease feeling better.
The sensory evaluation was carried out in four grades similar to dry feeling. (Lightness) The weight (g) of a woven / knitted fabric having a size of 1 m × 1 m was measured. That is, the unit weight is "g / m ² ".
Displayed in .

(Anti-frosting property) Two woven and knitted fabrics cut into a circle with a diameter of 10 cm were sampled, one of them was moistened with distilled water, and the upper side of a pair of discs rotating in opposite directions. Attach it to the disc and the other one to the lower disc in a dry state. Then, the two samples are rubbed against each other while being circularly moved for 10 minutes. After leaving for 4 hours after the end of rubbing, the degree of discoloration of the sample wetted with water was visually evaluated in the following 5 grades.

Grade 5: Very good with no discoloration observed. Grade 4: Good. Level 3: Normal. Grade 2: Discoloration and discoloration are recognized and defective. Grade 1: Remarkably poor discoloration.

(Water Absorption) The water absorption height (mm) due to the capillary phenomenon was measured based on JIS1096 (General woven / knitted fabric test method). The higher the water absorption height, the better the water absorption. (Hollowness rate) A cross section of a single hollow fiber was obtained by scanning microscope (SE
M) was taken in a photograph magnified 1500 times, and the total cross-sectional area S ₀ surrounded by the outer shape and the cross-sectional area S of the hollow portion were taken.
₁ was measured, and the hollow ratio P was calculated by the following calculation formula.

P (%) = (S ₁ / S ₀ ) × 100 Examples 1, 2 and 3 The cross section is a hollow quadrangle whose core component is 55% by weight of a polyester homopolymer as shown in FIG. A circular composite filament fiber having a sheath component of 45% by weight of a copolyester obtained by copolymerizing 4.5 mol% of 5-sodiumsulfoisophthalic acid is melt-spun and stretched to have a hollow ratio of 23.0% and a fineness. A polyester composite hollow multifilament yarn having 155 denier, 48 filaments and single fiber fineness of 3.2 denier was obtained.

Then, the obtained composite hollow multifilament yarn was subjected to actual twisting of 400 times / m, and false twisting temperatures were respectively 175 ° C. (Example 1), 165 ° C. (Example 2) and 155 ° C. The false twist number of 21 is different from that of (Example 3).
00 times / m (0.88T), false twisting tension 17.05g
(0.11 g / d) was false twisted. Subsequently, the above-mentioned three types of false twist textured yarns were respectively used as warp yarns and weft yarns to weave a medium-thickness woven fabric with a variable twill design (Sugiaya). Then, these three kinds of fabrics are subjected to relax refining, drying and dry heat setting (180 ° C) according to a conventional method, and then alkali treatment is carried out with a 1.5% aqueous solution of caustic soda at 80 ° C x 40 minutes, and sheaths are prepared for each. The copolyester component of the component was selectively eluted by 55% by weight and weight-reduced.

Next, these three kinds of fabrics were respectively treated with blue disperse dye Resoline Blue FBL (Bayer Co., Ltd.).
Manufactured by K.K.) at a dyeing concentration of 1.0% by weight and at 130 ° C. × 4
It was dyed for 5 minutes and finished. The results of the finished woven fabric are shown in Table 1. In addition, when observing the fiber cross-sectional shape of the decomposed yarn of the finished woven fabric, in all of the woven fabrics of Examples 1, 2 and 3, the outer shape and hollow portion of the rugged cross-section quadrilateral as shown in FIGS. It was a collection of hollow filaments of various embodiments. Furthermore, when observing the degree of ladle of the fiber cross section, the woven fabrics of Examples 1, 2, and 3 became larger in order, and the hollow ratio tended to become slightly smaller, but in all, the hollow portion was retained, It did not disappear. Note that FIG. 9 is a photograph of the cross section of the woven fabric of Example 1 taken with a scanning microscope.

[0036]

[Table 1] As is clear from Table 1, the fabrics of Examples 1, 2, and 3 were
All were blue midweight fabrics with a fine dry feel, a refreshing refreshing feel, and a soft, swelling and stinging texture with a wonderful high-class feel. In addition, it was lightweight, had high water absorption, and had excellent frosting resistance.

Comparative Example 1 and Comparative Example 2 A woven fabric was produced which was finished according to Example 1 except that false twisting was not applied (Comparative Example 1). Further, without using the composite filament fiber, using a hollow multifilament yarn in which the outer shape of the cross section and the hollow portion are both circular with only a polyester homopolymer, the fineness, the number of filaments,
Example 1 is the same as Example 1 except that the single fiber fineness and the hollowness are the same, and the false twisting temperature is 210 ° C.
A woven fabric was produced in accordance with the above (Comparative Example 2).

The results of these finished fabrics are shown in Table 1. As is clear from Table 1, in the woven fabric of Comparative Example 1, the square shape remains sharp in the cross section of the weaving yarn, but the texture is stiff, and the softness, crease feeling, and swelling feeling are lacking. It was In addition, the woven fabric of Comparative Example 2 had a large crushing of the weaving yarn, lacked a bulging feeling, and had a problem in anti-frosting property.

Example 4 The composite ratio of the copolymerized polyester in which the core component was 60% by weight of polyester homopolymer and the sheath component was 12.0% by weight of polyethylene terephthalate and 12.0% by weight of polyethylene glycol (molecular weight 1000) was used. As shown in FIG. 7, a composite filament fiber having a circular cross section and a hollow trapezoidal core is melt-spun and stretched to have a hollow ratio of 3
A polyester composite hollow multifilament yarn of 24 filaments with a fineness of 85 denier at 0.0% was obtained.

Next, the polyester composite hollow multifilament yarn is false twisted at a temperature of 160 ° C. and the false twist number is 280.
0 times / m, false twisting with a false twisting tension of 8.5 g, 1 after false twisting
A false twist additional twist yarn was obtained by applying 200 times / m of actual twist. Subsequently, the false twisted plied yarn was smoothly knitted with an interlock structure (gauge number: 32 GG) to form a knit. Next, after refining and setting the obtained knitted fabric according to a conventional method, it is subjected to alkali treatment with a 3.0% aqueous solution of caustic soda at 98 ° C. for 60 minutes to give 40% of the copolymerized polyester of the sheath component.
Wt% was selectively eluted.

Then, the above knitted fabric was dyed with a yellow disperse dye at 130 ° C. for 30 minutes to finish. The results of the finished knitted fabric are shown in Table 2. When the fiber cross section of the finished knitted fabric was observed, as shown in FIGS. 1 to 4, a variety of lathed quadrilateral shapes were gathered, and a continuous hollow portion was held inside.

[0042]

[Table 2] As is clear from Table 2, the obtained knitted fabric has a dry feeling,
It was a yellow-colored knit with a high-quality silky texture that had a refreshing, soft and swelling feel. Further, it was excellent in lightness and water absorption, and had good anti-frosting property.

Comparative Example 3 A knitted fabric was produced in the same manner as in Example 4 except that false twisting was not applied. This knitted fabric had a mediocre texture and lacked in softness and squeaky feeling. Example 5 A polyester composite multifilament hollow fiber was produced in accordance with Example 1 except that the fineness was 75 denier and the number of filaments was 36 filaments.

Next, the false twist temperature is 170 ° C. and the false twist number is 300.
After twisting at 0 times / m and false twisting tension 7.5g, 25
A false twist additional twist (strong twist) yarn was applied by applying a true twist of 00 times / m, and further, this false twist additional twist yarn was steamed at 80 ° C. for 20 minutes, and twist set. Subsequently, the false twisted-twisted yarn was used as a warp yarn and a weft yarn and woven into a Georgette crepe having a flat design. This woven fabric was textured and refined, set, and alkali-treated and dyed according to Example 1 to finish.

The finished woven fabric had a fine dry touch and a smooth refreshing feeling, and had an excellent texture. It also had high water absorption and excellent anti-frosting properties. In addition, the weaving yarns of the finished woven fabric include a lot of lazy diamond-shaped cross sections as shown in FIG.
Moreover, the hollow part is continuous in the yarn axis direction, and the hollow rate is 18%.
Met.

[0046]

As described above, the woven or knitted fabric according to the present invention has the following excellent characteristics without impairing the texture such as the swelling feeling and the lightness inherent to the woven or knitted fabric using the hollow fiber. You can (1) It has a dry feeling without sliminess or waxy feeling.

(2) It has a dry and refreshing feeling. (3) Soft and swelling is large. (4) It has an elegant texture with a slippery sound (a feeling of creaking). (5) It has excellent anti-frosting properties. Moreover, according to the manufacturing method of the present invention, it is possible to efficiently manufacture the woven or knitted fabric having the above-mentioned texture.

[Brief description of drawings]

FIG. 1 is a cross-sectional view illustrating a hollow fiber used in a woven or knitted fabric of the present invention.

FIG. 2 is a cross-sectional view illustrating another hollow fiber used in the woven or knitted fabric of the present invention.

FIG. 3 is a cross-sectional view illustrating still another hollow fiber used in the woven or knitted fabric of the present invention.

FIG. 4 is a cross-sectional view illustrating still another hollow fiber used in the woven or knitted fabric of the present invention.

FIG. 5 is a cross-sectional view illustrating a raw yarn (composite hollow filament) before producing the woven or knitted fabric of the present invention.

FIG. 6 is a cross-sectional view showing another example of the raw yarn (composite hollow filament) before manufacturing the woven or knitted fabric of the present invention.

FIG. 7 is a cross-sectional view showing still another example of the raw yarn (composite hollow filament) before producing the woven or knitted fabric of the present invention.

FIG. 8 is a cross-sectional view showing still another example of the raw yarn (composite hollow filament) before producing the woven or knitted fabric of the present invention.

FIG. 9 is a photograph of a cross section of the woven fabric obtained in Example 1, taken by a scanning microscope.

[Explanation of symbols]

1 polymer part (core component in case of composite filament fiber) 2 polymer part (sheath component) 3 hollow part

Claims (10)

[Claims] 1. A modified quadrilateral having a deformed quadrilateral whose cross-section is irregularly squashed, and comprising a plurality of modified cross-section hollow filaments having hollow portions which are substantially continuous in the filament axial direction. A woven or knitted fabric composed of multifilament yarns having different shapes among the plurality of modified cross-section hollow filaments as a woven or knitting yarn. 2. The woven or knitted fabric according to claim 1, wherein the hollow portion is a deformed quadrilateral which is irregularly squashed in cross section. 3. The woven or knitted fabric according to claim 1, wherein the deformed quadrilateral forming the outer shape has a shape having at least two portions having an acute angle at an edge where adjacent sides intersect with each other. 4. The deformed quadrilateral is formed by being deformed by a tightening force between constituent filaments generated by twisting the multifilament yarn. The woven or knitted fabric according to. 5. The twisting treatment is false twisting by false twisting and real twisting given before or after false twisting, and the woven or knitting yarn is a pretwisted falsetwisted yarn or a false twisted posttwisted yarn. Item 4. The woven or knitted fabric according to Item 4. 6. A core component made of a polyester having a substantially quadrilateral outer shape in a cross section and having a hollow portion continuous in the filament axial direction, and a sheath component made of a copolyester more easily dissolved by an alkali than the polyester. A multi-filament yarn consisting of a composite filament fiber composed of and is subjected to false twisting after false twisting, or false twisted and then true twisted into a false twisted yarn, and the false twisted yarn is obtained. To a woven or knitted fabric as a woven or knitted yarn, and then subjecting the woven or knitted fabric to alkali treatment to elute the sheath component of the composite filament fiber. 7. The method for producing a woven or knitted fabric according to claim 6, wherein the hollow portion is substantially quadrilateral in cross section. 8. The method for producing a woven or knitted fabric according to claim 6, wherein the outer shape of the sheath component of the composite filament fiber in the cross section is substantially circular. 9. The false twist temperature in the false twist process is 130.
The temperature is not less than 0 ° C and not more than 180 ° C.
The method for producing a woven or knitted fabric according to item. 10. The false twist number in the false twist process is 50 to 100% of the false twist number T (times / m) given by the following formula.
The method for producing a woven or knitted fabric according to claim 9, wherein T = (3.16 × 10 ⁴ /√D)×0.94 where D is the total fineness (denier) of the multifilament yarn