Stretch fabric

Abstract

To provide a stretch woven fabric which has a characteristic of eliminating degradation of pilling resistance due to repeated washing, such a characteristic having been unachievable so far, and which also has good bounce and resilience.SOLUTION: A stretch woven fabric comprises a spun yarn as a warp yarn and a composite false-twisted yarn as a weft yarn. The composite false-twisted yarn is formed by combining a polyester false-twisted yarn A and a polyester false-twisted yarn B which are obtained by separately false-twisting in the same direction, and have the number of entangling of 30 / m or more, the number of torque twisting of 40 T / m or more, and the percentage of crimp of 30% or more.SELECTED DRAWING: None

Description

[Technical field]

[0001] The present invention relates to a stretch fabric that exhibits excellent pilling resistance even after repeated washing over a long period of time. [Background technology]

[0002] Fibers made from thermoplastic polymers such as polyester and polyamide have various excellent properties including mechanical properties and dimensional stability. Therefore, they are used in various fields such as clothing, interiors, vehicle interiors, industrial materials, etc. On the other hand, as the uses of fibers become more diverse, the required properties are also becoming more diverse.

[0003] In particular, in recent years, there has been a demand for less restrictive wear and better movement-following capabilities, leading to high demands for stretch performance in clothing and other items, and a variety of stretch products have appeared on the market. In particular, woven fabrics that use spun yarn as part of the warp have a soft, fluffy texture and surface feel, making them ideal for use as uniform materials, casual materials, sports materials, and the like, and the demand for stretchability is also increasing.

[0004] Various methods have been proposed to impart stretchability to raw yarns constituting woven fabrics. For example, there is a method of imparting stretchability to woven fabrics by using normal false twist textured yarns as weft yarns. However, in woven fabrics using spun yarns as part of the warp yarns, in order to impart stretchability in the weft direction, it is necessary to weaken the tension in the warp direction of the fabric during dyeing and processing, which causes problems such as the appearance of wrinkles and the deterioration of the quality of the woven fabric. Furthermore, there is a problem that the fuzz of the warp yarns and the crimp of the weft yarns become entangled due to friction and impact caused by repeated washing and use, which deteriorates the pilling resistance.

[0005] Another method is to add stretchability to the fabric by mixing polyurethane fibers into the weft, but this method has problems such as poor color fastness, discoloration and color transfer, and deterioration of strength after repeated use.

[0006] Also, woven fabrics of latent crimp-producing fibers using side-by-side composite yarns have been proposed. For example, Patent Document 1 proposes latent crimp-producing composite fibers made of composite fibers in which two polymer components with different viscosities are bonded together in a side-by-side manner. When such latent crimp-producing composite fibers are used, the fibers are significantly curved toward the high shrinkage component side after heat treatment, and this continues to form a three-dimensional coil structure. Therefore, the structure expands and contracts like a spring, and stretchability can be imparted to the woven fabric. However, these side-by-side composite fibers have the problem that the coil crimps pop out onto the surface of the fabric due to friction and impact caused by repeated washing and use, and further peeling occurs at the composite fiber interface, resulting in reduced pilling resistance.

[0007] Patent Document 2 proposes a woven fabric that partially uses an eccentric sheath-core composite fiber made of two polymers, component a and component b, in which component a is completely covered with component b in the cross section, and takes abrasion resistance into consideration. However, this method also has the problem that the coil crimp pops out onto the surface of the fabric due to friction and impact caused by repeated washing and use, and becomes entangled with the fuzz of the warp yarn, reducing pilling resistance.

[0008] Patent Document 3 proposes a stretch fabric using a composite yarn of a false twisted crimped yarn having torque in the S direction and a false twisted crimped yarn having torque in the Z direction. While this method can certainly produce a stretch fabric with a flat surface, there is a problem in that in fabrics using spun yarn for the warp, the bulky crimp of the composite yarn tends to get entangled with the fluff of the spun yarn, resulting in a decrease in pilling resistance after repeated washing. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] Japanese Patent Application Publication No. 09-157941 [Patent Document 2] JP 2019-214798 A [Patent Document 3] JP 2009-138287 A Summary of the Invention [Problem to be solved by the invention]

[0010] An object of the present invention is to provide a stretch fabric which overcomes the problem of pilling resistance after repeated washing, which has been a problem with conventional stretch fabrics, and has excellent firmness and stiffness. [Means for solving the problem]

[0011] In order to solve the above problems, the stretch fabric of the present invention has the following structure: That is, the fabric includes a spun yarn as a warp yarn and a composite false-twisted yarn as a weft yarn, and the composite false-twisted yarn is in the form of a yarn formed by combining polyester false-twisted yarn A and polyester false-twisted yarn B which are false-twisted separately in the same direction; The polyester false-twisted yarn A and the polyester false-twisted yarn B are composed of non-conjugated yarns made of polyethylene terephthalate, and The above The number of interlacings of the composite false twist yarn is 30 or more / m, the torque twist number is 40T / m or more, and the crimp rate is 30% or more. The yarn length difference of the composite false twist yarn is 3% or less, and the pilling after repeated washing is 3.5 or more. A stretch fabric characterized by:

[0012] The stretch fabric of the present invention is made of a non-conjugated yarn of polyethylene terephthalate, in which polyester false-twisted yarn A and polyester false-twisted yarn B are non-conjugated yarns of polyethylene terephthalate. do.

[0013] In the stretch fabric of the present invention, it is preferred that the polymers constituting the polyester false-twisted yarn A and the polyester false-twisted yarn B are the same.

[0014] In the stretch fabric of the present invention, the yarn length difference of the composite false twist yarn is preferably 3% or less.

[0015] The stretch fabric of the present invention has a pilling level of 3.5 or higher after repeated washing. do. Effect of the Invention

[0016] According to the present invention, it is possible to obtain a stretch woven fabric which overcomes the pilling resistance after repeated washing that was previously unattainable and has excellent firmness and stiffness. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] The stretch fabric of the present invention is a fabric containing a spun yarn as the warp and a composite false-twisted yarn as the weft. By using a spun yarn as the warp, a soft and fluffy fabric can be obtained, but when a false-twisted yarn is used as the weft to obtain stretchability, there is a problem that the fuzz of the spun warp yarn and the crimp of the false-twisted weft yarn become entangled with repeated washing, making the fabric prone to pilling.

[0018] As a result of extensive investigations, the present invention has succeeded in obtaining a stretch fabric with excellent pilling resistance, in which the fuzz of the spun warp yarn and the crimp of the polyester false-twisted weft yarns A and B are combined, which are separately false-twisted in the same direction, and the crimp of the polyester false-twisted yarns A and B is allowed to occur while maintaining a convergent state, that is, by using a composite false-twisted yarn for the weft with an entanglement number of 30 or more / m, a torque twist number of 40 T / m or more, and a crimp rate of 30 or more.

[0019] The number of entanglements of the composite false-twisted yarn constituting the stretch woven fabric of the present invention is 30 or more per meter, so that the crimps in the woven fabric can be brought into a convergent form. The preferred number of entanglements is 60 to 150 per meter. If the number of entanglements is less than 30 per meter, the crimps of the composite false-twisted yarn tend to become entangled with the fluff of the spun yarn, and pilling resistance after repeated washing deteriorates.

[0020] Furthermore, by setting the torque twist number of the composite false-twist yarn constituting the stretch woven fabric of the present invention to 40 T / m or more, the crimp of the composite false-twist yarn can be maintained in a convergent form by simultaneously generating a torque during dyeing. A preferred torque generation number is 50 to 200 T / M or less. If the torque generation number is less than 40 T / M, the torque generation during dyeing is small and the bulkiness of the composite textured yarn increases, so that the crimp is easily entangled with the fluff of the spun yarn, and pilling resistance after repeated washing deteriorates.

[0021] Furthermore, by making the composite false twist yarn constituting the stretch woven fabric of the present invention have a crimp percentage of 30% or more, the woven fabric can be given high stretchability. The preferred crimp percentage is 30 to 60%. If the crimp percentage is less than 30%, the woven fabric cannot be given high stretchability.

[0022] In addition, the yarn length difference of the composite false-twisted yarn constituting the stretch woven fabric of the present invention is preferably 3% or less, since this makes it difficult for the single yarns of the composite false-twisted yarn to come out to the surface of the woven fabric after repeated washing, thereby improving pilling resistance.The yarn length difference of the composite false-twisted yarn is more preferably 1% or less.

[0023] It is also important that the composite false-twisted yarn constituting the stretch fabric of the present invention is in the form of a composite of polyester false-twisted yarn A and polyester false-twisted yarn B which have been false-twisted separately in the same direction.

[0024] Examples of polyester include polyethylene terephthalate, polybutylene terephthalate, and polypropylene terephthalate. Among them, polyethylene terephthalate, which has stable crimping, is preferable.

[0025] There is no problem if any component such as a sulfonic acid component, a dicarboxylic acid component, a diol component or an oxycarboxylic acid component is copolymerized in the polymer of the polyester false twist yarn A and polyester false twist yarn B. For example, if the yarn has an anionic moiety such as a sulfonic acid group, it can have cationic dyeability due to interaction with a cationic dye having a cationic moiety, but if both the polyester false twist yarn A and polyester false twist yarn B use cationic dyeable polymers and have the same dyeability, this is preferable because pilling caused by friction and impact due to repeated washing and use is less noticeable.

[0026] In addition, polyester false-twisted yarn A and polyester false-twisted yarn B are false-twisted separately in the same direction and then combined, resulting in a configuration in which the crimps of different phases overlap, making it difficult for the fuzz of the spun yarn to tangle even after repeated washing, improving pilling resistance. do.

[0027] Furthermore, when the polymers constituting the polyester false twisted yarn A and polyester false twisted yarn B are the same, the crimp development performance is the same, only the phase is different, and the crimps can be made to overlap, which is more preferable.

[0028] In addition, the above-mentioned polyester false-twisted yarn A and polyester false-twisted yarn B are composed of non-conjugated yarns that are easy to maintain the converged crimped shape. do. With this configuration, the coil crimp is less likely to come out onto the surface of the woven fabric even when subjected to friction or impact during repeated washing, improving pilling resistance.

[0029] In addition, the above-mentioned polyester false twist yarn A and polyester false twist yarn B can be selected to have any shape in cross section, such as a round, triangular, flat, hexagonal, L-shaped, T-shaped, W-shaped, octave-shaped, dog-bone or other polygonal shape, various shapes, hollow shapes, etc., but it is preferable to make the cross sections of A and B the same, since this will enable the crimp expression performance to be the same, with only the phase being different, and the crimps to overlap.

[0030] Furthermore, the above-mentioned polyester false-twisted yarn A and polyester false-twisted yarn B can contain, as necessary, matting agents such as titanium oxide, flame retardants, lubricants, antioxidants, inorganic fine particles or organic compounds as coloring pigments, and carbon black, within the scope of the object of the present invention. However, it is preferable to use the same ingredients, because this will result in a form in which the crimp expression performance is the same but the phase is different and the crimps overlap.

[0031] The fineness of the polyester false twist yarn A and polyester false twist yarn B is preferably 30 to 200 dtex, in order to impart stretchability and a fluffy feel to the woven fabric. It is more preferable that the fineness of the polyester false twist yarn A and polyester false twist yarn B is the same, since the yarns are different in phase and the crimps overlap.

[0032] In addition, the single yarn fineness of the polyester false twist yarn A and polyester false twist yarn B is preferably 0.5 to 7 dtex from the viewpoint of imparting stretchability and softness to the woven fabric. It is more preferable that the single yarn fineness of the polyester false twist yarn A and polyester false twist yarn B is the same, since the yarns are different in phase and the crimps overlap each other.

[0033] In addition, the material of the spun warp yarn used in the present invention can be any of the usual synthetic fibers, as well as cellulosic fibers such as acetate, regenerated cellulosic fibers, natural fibers such as cotton, silk, and animal fibers, or blends thereof. Among them, polyester blends, which have little fraying of short fibers even after repeated washing, are preferably used. In addition, the warp yarn is preferably not only spun yarn, but also an arrangement of spun yarn and filament, since pilling is suppressed even after repeated washing.

[0034] From the viewpoint of achieving both spinnability and a soft feel, the single fiber fineness of the spun yarn is preferably in the range of 0.5 to 10 dtex, more preferably 0.7 to 4.0 dtex, which is the single fiber fineness used in ordinary composite spun yarns.

[0035] From the viewpoint of quality, the fiber length of the spun yarn is preferably in the range of 25 to 80 mm, and more preferably in the range of 30 to 60 mm.

[0036] The yarn count of the spun yarn is preferably in the range of 10 to 100 (cotton type), but this yarn count can be appropriately selected depending on the application. For example, for woven fabrics for clothing, a yarn count of 20 to 80 (cotton type) is preferred.

[0037] The twist factor of the spun yarn is preferably in the range of 2.0 to 5.0, but this twist factor can be appropriately selected depending on the application. The twist factor does not need to be constant, and can be changed in the yarn longitudinal direction of the composite spun yarn depending on the application.

[0038] The stretch fabric of the present invention can be obtained by the following manufacturing method.

[0039] When spinning the raw yarn for the composite false twist yarn constituting the stretch fabric of the present invention, it is preferred that the amorphous portion is in a highly oriented state in order to improve the crimp expression rate, and the preferred spinning speed is 2,500 to 3,800 m / min.

[0040] Next, in producing the composite false twist textured yarn used in the present invention, the raw yarn of polyester false twist yarn A and the raw yarn of polyester false twist yarn B are separately false twisted in the same direction (false twisting in S and S directions, or Z and Z directions) and then post-entangled, thereby obtaining a composite textured yarn with high crimp and high expressed torque, and the convergence form of the crimp within the fabric can be maintained.

[0041] Any false twist conditions can be selected. The twister may be of the spindle type, friction disk type, or belt nip type, but the friction disk type is preferred because it can false twist at high speed and has relatively little single yarn snare. In the case of a contact heater, the false twist temperature is preferably 170 to 225°C, since it can impart strong crimp. The false twist number is preferably set in the range where the false twist coefficient (false twist number (T / M) x fineness (dtex) 0.5) is 27,000 to 33,000, since it can impart strong crimp. Here, if the false twist numbers of the false twist yarns A and B are the same, it is more preferable because the false twist numbers are different only in phase and the crimps can overlap, making it possible to achieve a form in which the yarns are more flexible.

[0042] As for the entangling conditions, the entangling pressure is preferably 0.25 to 0.5 MPa, taking into consideration the balance between stretchability and convergence.

[0043] Regarding the yarn processing speed, the faster the speed, the higher the productivity, which is preferable, but in consideration of stable processing, a speed of 100 to 800 (m / min) is preferable.

[0044] The composite false twist textured yarn used in the present invention can be twisted using any twisting machine such as a down twister or a double twister, but since it becomes difficult to obtain crimp, the number of twists is preferably 500 T / M or less. More preferably, the yarn is not twisted.

[0045] The stretch fabric of the present invention can be woven using a commonly used loom such as a normal loom, a rapier, a water jet loom, an air jet loom, etc., but is not limited to these. The weave can be any weave such as plain, twill, satin, amunzen, double weave, etc.

[0046] In addition, the stretch fabric of the present invention may be subjected to various types of additional processing, such as conventional water absorption processing, water repellency processing, nap raising processing, ultraviolet shielding, or processing to impart functions such as antibacterial agents, antiviral agents, deodorizing agents, insect repellents, and retroreflective agents, as long as the object of the present invention is not impaired.

[0047] In addition, in the case of the stretch fabric of the present invention, in addition to the usual pilling evaluation, the pilling after repeated washing is rated at 3.5 or higher, which means that pilling does not occur even in an environment simulating actual wearing after repeated washing. hard. The preferable pilling level after repeated washing is grade 4 or higher.

[0048] The stretch fabric obtained by the present invention is suitable for use as clothing, such as uniform material, student clothing material, casual material, sports material, formal material, etc. EXAMPLES

[0049] The present invention will now be described more specifically with reference to examples. (1) Fineness Using a measuring machine with a frame circumference of 1.0 m, 100 skeins were produced, and the fineness was measured according to the following formula.

[0050] Fineness (dtex) = Weight of skein for 100 uses (g) x 100 (2) Degree of entanglement The degree of entanglement is the number of entangled parts per meter under a tension of 0.1 cN / dtex, and is calculated by inserting a pin into the non-entangled part of the yarn under a tension of 0.02 cN / dtex, moving the pin up and down the length of the yarn over 1 m with a tension of 0.1 cN / dtex, recording the distance traveled as the non-entangled part where the pin moves without resistance, and the part where the pin stops is the entangled part. This process is repeated 30 times, and the degree of entanglement per meter is calculated from the average distance of the non-entangled parts. (3) Crimp rate The yarn was wound 10 times around a measuring machine with a circumference of 0.8 m under a tension of 90 mg / dtex to take a skein, which was then hung on a rod of 2 cm or less and left for about 24 hours. The skein was wrapped in gauze, treated with hot water at 90°C for 20 minutes under no tension, and then hung on a rod of 2 cm or less and left for about 12 hours. One end of the skein after leaving was hung on a hook, and the other end was subjected to an initial load and a measurement load, and the skein was left for 2 minutes. The initial load (g) at this time was 2 mg / dtex, the measurement load (g) was 90 mg / dtex, and the water temperature was 20 ± 2°C. The inner length of the left skein was measured and defined as L. Furthermore, the measurement load was removed and the skein was left for 2 minutes with only the initial load, and the inner length of the left skein was measured and defined as L1. The shrinkage was calculated using the following formula, and this operation was repeated 5 times to determine the average value.

[0051] Crimp rate (%)={(L-L1) / L}×100 (4) Torque twist Approximately 75 cm of composite false twist yarn is stretched horizontally, an initial load of 0.02 mN / dtex is hung from the center, and both ends are pulled together. The yarn begins to rotate due to the residual torque, but it is held in this state until the initial load stops, resulting in a twisted yarn. The number of twists over a 25 cm length of the twisted yarn thus obtained is measured with a twist detector under a load of 1 mN / dtex. The obtained number of twists (T / 25 cm) is multiplied by 4 to obtain the torque (T / m). (5) Yarn length difference Approximately 10 cm of composite false-twisted yarn was carefully disassembled into polyester false-twisted yarn A and polyester false-twisted yarn B, and the lengths of the disassembled yarns were measured. The longer one was set as the maximum length and the shorter one as the minimum length, and the yarn length difference was calculated using the following formula. This process was repeated 10 times, and the average value was rounded off to the nearest decimal place.

[0052] Thread length difference (%) = (maximum length - minimum length) / minimum length x 100 (6) Stretch rate (%) The elongation rate was measured under a load of 1.5 kgf (14.7 N) according to Method B of JIS L 1096 (2010). (7) Pilling resistance evaluation The washing cycle was performed once in a two-tub washing machine with a liquid temperature of 40°C, a wash time of 5 minutes, rinsing at 30°C for 2 minutes twice, and a spin cycle of 30 seconds. Kao's "Attack" (registered trademark) was used as the detergent at 1g / L, with a liquid volume of 40L and a combined weight of 830g for the test cloth and the cotton cloth used as the guide cloth. After repeating this washing process 20 times, a pilling evaluation was performed according to JIS L 1076 (2018) Method A, and a grade was determined. A grade of 3.5 or higher was considered to be a pass. (8) Stiffness Sensory evaluation was done on a four-point scale: very good firmness, good firmness, slightly insufficient firmness, and insufficient firmness, and the result was determined to be closest to the average of the ratings of 10 randomly selected people.

[0053] <Example 1> First, polyethylene terephthalate with a circular cross section was spun at a spinning speed of 3,000 (m / min) to obtain two polyethylene terephthalate partially oriented yarns with a fineness of 140 dtex, 36 filaments, and elongation of 140%. The two partially oriented yarns were then false-twisted separately in the S direction using a friction false-twisting machine at a processing speed of 500 m / min, a heater temperature of 215°C, a draw ratio of 1.65 times, and a false-twist coefficient of 29,000, and then interlaced at an interlacing pressure of 0.3 MPa to obtain a composite textured yarn with a fineness of 167 dtex, interlacing number of 68 / m, torque twist number of 52 T / m (S direction), crimp rate of 41%, and yarn length difference of 0%.

[0054] In addition, polyethylene terephthalate staple fibers with a single fiber size of 1.45 dtex and fiber length of 38 mm were blended with cotton fibers in a ratio of 65:35, and through a normal spinning process, two-ply spun yarn with a cotton count of 45 / 2 was obtained.

[0055] Then, using the above spun yarn as the warp and the above composite processed yarn as the weft, a 2 / 1 twill fabric was woven on an air jet loom. The resulting woven fabric was then subjected to continuous spread-spread scouring at 98°C, intermediate setting at 180°C, and navy blue dyeing at 130°C using disperse and reactive dyes, and finally a finishing setting at 160°C to produce a product with a processed density (warp: 125 threads / 2.54 cm, weft: 105 threads / 2.54 cm).

[0056] The resulting fabric had a stretch rate of 18%, and a pilling resistance rating of 4.5 before washing and 4.5 after 20 washes. Even after repeated washing over a long period of time, the fabric had excellent pilling resistance and firmness.

[0057] <Example 2> First, polyethylene terephthalate having a circular cross section was spun at a spinning speed of 3,000 (m / min) to obtain a partially oriented polyethylene terephthalate yarn having a fineness of 140 dtex, 36 filaments, and an elongation of 140%.

[0058] On the other hand, polybutylene terephthalate having a circular cross section was spun at a spinning speed of 3,000 (m / min) to obtain a partially oriented polybutylene terephthalate yarn having a fineness of 140 dtex, 36 filaments and an elongation of 138%.

[0059] The two partially oriented yarns were then false-twisted separately in the S direction using a friction false-twisting machine at a processing speed of 500 m / min, a heater temperature of 210°C, a draw ratio of 1.65 times, and a false-twist coefficient of 28,000.Then, with a polyethylene terephthalate core yarn and a polybutylene terephthalate sheath yarn, they were interlaced at a core-sheath overfeed difference of 4% and an entanglement pressure of 0.3 MPa, to obtain a composite textured yarn with a fineness of 167 dtex, number of entanglements: 75 / m, torque twist number: 44 T / m (S direction), crimp rate: 41%, and yarn length difference: 4%.

[0060] Thereafter, a woven fabric was produced in the same manner as in Example 1, and dyed to produce a product with a processed density (warp threads: 125 threads / 2.54 cm, weft threads: 105 threads / 2.54 cm).

[0061] The resulting fabric had a stretch rate of 20%, and a pilling resistance rating of 4.5 before washing and 3.5 after 20 washes. Even after repeated washing over a long period of time, the fabric had excellent pilling resistance and firmness.

[0062] <Example 3> First, polyethylene terephthalate with a circular cross section was spun at a spinning speed of 3,000 (m / min) to obtain two polyethylene terephthalate partially oriented yarns with a fineness of 140 dtex, 36 filaments, and elongation of 140%. The two partially oriented yarns were then false-twisted separately in the S direction using a pin false-twisting machine at a processing speed of 100 m / min, a heater temperature of 220°C, a draw ratio of 1.65 times, and a false-twist coefficient of 32,000, and then interlaced at an interlacing pressure of 0.35 MPa to obtain a composite textured yarn with a fineness of 167 dtex, interlacing number of 93 / m, torque twist number of 68 T / m (S direction), crimp rate of 48%, and yarn length difference of 0%.

[0063] Thereafter, a woven fabric was produced in the same manner as in Example 1, and dyed to produce a product with a processed density (warp threads: 125 threads / 2.54 cm, weft threads: 105 threads / 2.54 cm).

[0064] The resulting fabric had a stretch rate of 25%, and a pilling resistance rating of 4.5 before washing and 4.5 after 20 washes. Even after repeated washing over a long period of time, the fabric had excellent pilling resistance and firmness.

[0065] <Comparative Example 1> First, polyethylene terephthalate with a circular cross section was spun at a spinning speed of 3,000 (m / min) to obtain a polyethylene terephthalate partially oriented yarn with a fineness of 280 dtex, 72 filaments, and elongation of 142%. The partially oriented yarn was then false-twisted in the S-direction by a friction false-twisting machine at a processing speed of 500 m / min, a heater temperature of 215°C, a draw ratio of 1.65 times, and a false-twist coefficient of 29,000, and then interlaced at an interlacing pressure of 0.2 MPa to obtain a false-twisted yarn with a fineness of 330 dtex, interlacing number of 50 / m, torque twist number of 45 T / m (S-direction), and crimp rate of 29%.

[0066] Thereafter, a woven fabric was produced in the same manner as in Example 1, and dyed to produce a product with a processed density (warp threads: 120 threads / 2.54 cm, weft threads: 105 threads / 2.54 cm).

[0067] The resulting fabric had a stretch rate of 8%, and its pilling resistance was rated as grade 4 before washing and grade 2.5 after 20 washes. The fabric had insufficient stretchability and pilling resistance after long-term repeated washing, and also had a somewhat lacking firmness.

[0068] <Comparative Example 2> First, polyethylene terephthalate with a circular cross section was spun at a spinning speed of 3,000 (m / min) to obtain a polyethylene terephthalate partially oriented yarn with a fineness of 280 dtex, 72 filaments, and elongation of 142%. The partially oriented yarn was then false-twisted in the S direction and Z direction separately using a friction false-twisting machine at a processing speed of 500 m / min, a heater temperature of 215°C, a stretch ratio of 1.65 times, and a false-twist coefficient of 29,000, and then interlaced at an interlacing pressure of 0.3 MPa to obtain a false-twisted yarn with a fineness of 330 dtex, interlacing number of 70 / m, torque twist number of 8 T / m (S direction), and crimp rate of 38%.

[0069] Thereafter, a woven fabric was produced in the same manner as in Example 1, and dyed to produce a product with a processed density (warp threads: 125 threads / 2.54 cm, weft threads: 105 threads / 2.54 cm).

[0070] The resulting fabric had a stretch percentage of 16%, and its pilling resistance was rated as grade 4.5 before washing and grade 3 after 20 washes. It had excellent firmness, but its pilling resistance after repeated washing over a long period of time was insufficient.

[0071] <Comparative Example 3> First, polyethylene terephthalate having a circular cross section was spun at a spinning speed of 3,000 (m / min) to obtain a partially oriented polyethylene terephthalate yarn having a fineness of 140 dtex, 36 filaments, and an elongation of 140%.

[0072] On the other hand, polyethylene terephthalate having a circular cross section and copolymerized with 0.3 mol% of 5-sodium sulfoisophthalic acid was spun at a spinning speed of 3,000 (m / min) to obtain a partially oriented polyethylene terephthalate yarn with a fineness of 140 dtex, 36 filaments, and an elongation of 145%.

[0073] The two partially oriented yarns were then false-twisted separately in the S direction using a friction false-twist processing machine at a processing speed of 500 m / min, a heater temperature of 180°C, a draw ratio of 1.65 times, and a false-twist coefficient of 27,000, and then interlaced at an entanglement pressure of 0.3 MPa to obtain a composite textured yarn with a fineness of 167 dtex, number of entanglements: 64 / m, torque twist number: 55 T / m (S direction), crimp rate: 25%, and yarn length difference: 0%.

[0074] Thereafter, a woven fabric was produced in the same manner as in Example 1, and dyed to produce a product with a processed density (warp threads: 122 threads / 2.54 cm, weft threads: 105 threads / 2.54 cm).

[0075] The resulting fabric had a stretch rate of 10%, and its pilling resistance was rated as grade 4.5 before washing and grade 2 after 20 washes. The fabric had insufficient stretchability and pilling resistance after long-term repeated washing, and also had a somewhat lacking firmness.

[0076] <Comparative Example 4> First, polyethylene terephthalate with a circular cross section was spun at a spinning speed of 3,000 (m / min) to obtain two polyethylene terephthalate partially oriented yarns with a fineness of 140 dtex, 36 filaments, and elongation of 140%. The two partially oriented yarns were then false-twisted separately in the S direction using a friction false-twisting machine at a processing speed of 500 m / min, a heater temperature of 215°C, a draw ratio of 1.65 times, and a false-twist coefficient of 29,000, and then interlaced at an interlacing pressure of 0.15 MPa to obtain a composite textured yarn with a fineness of 167 dtex, interlacing number of 21 / m, torque twist number of 44 T / m (S direction), crimp rate of 43%, and yarn length difference of 0%.

[0077] Thereafter, a woven fabric was produced in the same manner as in Example 1, and dyed to produce a product with a processed density (warp threads: 125 threads / 2.54 cm, weft threads: 105 threads / 2.54 cm).

[0078] The resulting fabric had a stretch percentage of 18%, and its pilling resistance was rated as grade 4.5 before washing and grade 3 after 20 washes. It had excellent firmness, but its pilling resistance after repeated washing over a long period of time was insufficient.

[0079] <Comparative Example 5> First, polyethylene terephthalate having a circular cross section was spun at a spinning speed of 3,000 (m / min) to obtain a partially oriented polyethylene terephthalate yarn having a fineness of 140 dtex, 36 filaments, and an elongation of 140%.

[0080] Meanwhile, polyethylene terephthalate and polybutylene terephthalate were extruded from a side-by-side type spinneret in a weight ratio of 50 / 50 and spun at a spinning speed of 3,500 (m / min) to obtain a conjugate partially oriented yarn with a fineness of 120 dtex, 36 filaments, and an elongation of 126%. The two partially oriented yarns were then twisted in a friction false twisting machine at a processing speed of 500 m / min, a heater temperature of 215°C, a draw ratio of 1.55 times, and a false twist coefficient of 31,000, after which they were composite false twisted in the S direction, and then interlaced at an entanglement pressure of 0.3 MPa to obtain a composite textured yarn with a fineness of 162 dtex, number of entanglements: 55 / m, torque twist number: 51 T / m (S direction), crimp rate: 52%, and yarn length difference: 8%.

[0081] Thereafter, a woven fabric was produced in the same manner as in Example 1, and dyed to produce a product with a processed density (warp threads: 128 threads / 2.54 cm, weft threads: 105 threads / 2.54 cm).

[0082] The resulting woven fabric had a stretch percentage of 27%, and its pilling resistance was rated as grade 3.5 before washing and grade 2 after 20 washes. It had excellent firmness, but its pilling resistance after repeated washing over a long period of time was insufficient. [Industrial Applicability]

[0083] The stretch woven fabric of the present invention is suitably used as clothing material for uniforms, student clothing, casual wear, sportswear, formal wear, and the like.

Claims

1. A stretch woven fabric comprising a spun yarn for the warp and a composite false-twisted yarn for the weft, the composite false-twisted yarn being in the form of a composite yarn of polyester false-twisted yarn A and polyester false-twisted yarn B which have been false-twisted separately in the same direction, the polyester false-twisted yarn A and polyester false-twisted yarn B being composed of non-conjugated yarns made of polyethylene terephthalate, the composite false-twisted yarn having an entanglement number of 30 or more / m, a torque twist number of 40 T / m or more, a shrinkage rate of 30% or more, and having a pilling level of 3.5 or more after repeated washing.

2. 2. The stretch fabric according to claim 1, wherein the polyester false-twist yarn A and the polyester false-twist yarn B are made of the same polymer.

3. 3. The stretch fabric according to claim 1, wherein the yarn length difference of the composite false twist yarn is 3% or less.