Fabric

Abstract

To provide a stretch material suitable for a comfort apparel having stretch performance and repulsive feeling with an appropriate amount of tightening feeling, and comfortable smooth tactile, and capable of widely applying to from casual use to sport use for intensive movement.SOLUTION: A textile is constituted at least partly by a crimped fiber conjugated with different polymers, where the textile surface roughness (Ra) is 40 μm or less, the surface roughness CV% is 20 or less, and the textile expansion rate is 20% or more.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a stretch fabric. [Background technology]

[0002] Synthetic fibers made of polyester, polyamide, etc. have excellent mechanical properties and dimensional stability, and are therefore widely used in a variety of applications, from clothing to industrial materials. With the recent changes in lifestyle and the scenes in which they are worn, the characteristics people require from textile products have become more diverse, and there is a continuing demand for high-performance, comfortable materials, especially for clothing textiles worn by humans.

[0003] In recent years, basic properties required for clothing textiles include reduced feeling of restriction when worn and the ability to follow movements, and various proposals have been made regarding stretch textiles that aim to allow clothing to stretch and shrink without causing stress when moving.

[0004] Generally, side-by-side type composite fibers and eccentric core-sheath composite fibers are widely used as fibers for stretch textiles. These composite fibers are latent crimp fibers that exhibit crimping even before heat treatment, and the crimp structure that these fibers exhibit expands and contracts like a spring when stretched, thereby imparting sufficient stretch performance to the fabric.

[0005] The evolution of stretch textiles is being vigorously pursued, and in addition to improving stretch performance, attention is being focused on comfortable stretch textiles that have a variety of additional functions.

[0006] For example, in stretch textiles, Patent Documents 1 and 2 disclose techniques for controlling the surface morphology of the fabric and the textile surface by utilizing shrinkage due to crimp development.

[0007] Patent Document 1 describes a stretch textile that uses a conjugated fiber having crimp-producing properties as the weft, in which different polyester polymers, each of which is a polyester mainly composed of polytrimethylene terephthalate, are bonded side-by-side along the fiber length, making it possible to control the unevenness of the textile surface by the shrinkage caused by the crimp.

[0008] Patent Document 2 proposes a woven or knitted fabric using a false-twisted yarn of an eccentric sheath-core composite fiber made of two polymer components with different viscosities, with polybutylene terephthalate as the core component and polyethylene terephthalate as the sheath component. When this false-twisted yarn of eccentric sheath-core composite fiber is used, the fiber is significantly curved toward the high shrinkage component after heat treatment, and this continues to form a three-dimensional spiral structure. It is disclosed that the structure expands and contracts like a spring, giving the fabric sufficient stretchability and abrasion resistance, and further having a uniform and smooth appearance without wrinkles or streaks, and a woven or knitted fabric with a smooth and delicate texture can be obtained. Furthermore, with the expansion of stretch textiles, in order to accommodate their use in women's clothing and in casual settings in addition to sportswear, additional functions such as softness and moderate resilience, which are contradictory properties, are being pursued, and a beautiful appearance is being imparted, and Patent Document 3 proposes a technique for intertwining false twist textured yarns with different twist directions. Patent Document 3 claims that by combining textured yarns with different twist directions, it is possible to achieve a stretchable woven fabric with a flat fabric surface by disrupting the unevenness caused by the twist direction of the yarn bundles seen in conventional techniques. [Prior art documents] [Patent documents]

[0009] [Patent Document 1] JP 2002-004149 A (Claims) [Patent Document 2] JP 2019-214798 A (Claims) [Patent Document 3] JP 2009-138287 A (Claims) Summary of the Invention [Problem to be solved by the invention]

[0010] In Patent Document 1, the unevenness of the fabric surface reduces the contact area with the skin and provides an excellent dry feel, but in some cases the difference between the unevenness may be large, resulting in a rough and uncomfortable feel. In addition, since the unevenness is non-uniform, the fabric may be inferior in softness and smoothness, limiting its application.

[0011] In Patent Document 2, the stretch performance of the fabric is sufficient and the fabric has an appearance without wrinkles or streaks, but the fibers are in close contact with each other, and each fiber may not be able to fully express crimp. In this case, adjacent fibers may be bundled together to express crimp, which may cause unnecessary streaks on the fabric surface and may result in a decrease in fabric quality. In addition, when the fibers that have expressed crimp are present together, it is difficult to form voids between adjacent fibers, resulting in a yarn bundle form with poor bulkiness, which may result in a lack of fluffiness of the fabric and a paper-like fabric. In addition, in order to eliminate this lack of bulkiness, false twist processing or the like may be performed, but even in this case, in order to make the unevenness of the fabric surface smooth to the touch, it may be necessary to adjust the structure or advanced processing process, which may restrict the development of applications.

[0012] Patent Document 3 also aims to achieve smoothness in the fabric by providing two types of twist directions for false twist processing. However, when using false twist textured yarn, as described above, in addition to the need to undergo structure and complex high-level processes, the fabric is originally based on mechanically imparted bending as the basis for crimping, which can result in insufficient stretch performance and resilience.

[0013] As described above, with the conventional techniques, it was difficult to achieve both high functionality, such as suppression of a feeling of restriction when worn (soft stretch) and the ability to follow movements (flexibility), both of which are required of today's stretch materials, and a good feel, such as a soft texture and smooth fabric surface. Thus, there was a demand for a stretch material suitable for comfortable clothing that can be used for a wide range of purposes, from casual to sports involving vigorous movements, and that has a stretch performance with a moderate feeling of tightness, a resilience, and a comfortable, smooth feel. [Means for solving the problem]

[0014] The object of the present invention is achieved by the following means. (1) An eccentric core-sheath fiber consisting of two types of polymers, component A and component B, whose melt viscosity difference is 10 Pa s or more, in which component A is completely covered by component B, and in which the perimeter of the part of the cross section that is 1.05 times or less of the minimum thickness of component B covering component A is 1 / 3 or more of the perimeter of the entire fiber, Single fiber size 3.0 dtex or less and , the elastic modulus is 70cN / dtex or more, All warp and weft yarns are made of crimped fibers with a twist of 500 T / m or more. The fabric surface roughness (Ra) is 40 μm or less, and the surface roughness CV% is 20 or less, The ratio of hysteresis (2HB) to stiffness (B), 2HB / B, is 2.0 cm -1 Below is A woven fabric characterized by having a fabric elongation rate of 20% or more. (2) winding The above-mentioned (1), characterized in that both the A component and the B component constituting the shrink fiber are components mainly composed of polyethylene terephthalate. To The fabric described. ( 3) The fabric stretch recovery rate is 80% or more. Or (2) The fabric according to claim 1. ( 4 ) The above (1) to ( 3 A textile product in which the woven fabric described in 。 Effect of the Invention

[0015] According to the present invention, a stretch fabric can be provided that exhibits fine and uniform crimping, and thus has an appropriate stretch performance with a tight fit, a bouncy feel, and a comfortable, smooth feel, making it suitable for use as a comfortable clothing textile. [Brief description of the drawings]

[0016] [Figure 1] 1 is an example of a photograph of a fiber cross section of a crimped fiber used in a woven fabric of the present invention. [Diagram 2] 1 is an example of a crimped fiber used in the woven fabric of the present invention, and is a fiber cross section for explaining the position of the center of gravity in the fiber cross section. [Diagram 3] 1 is a fiber cross section for explaining the fiber diameter (D) and minimum thickness (S) in the fiber cross section of the crimped fiber used in the woven fabric of the present invention. [Figure 4] 1 is a fiber cross section for explaining the IFR (the radius of curvature of the interface between component A and component B in the fiber cross section) in the fiber cross section of the crimped fiber used in the woven fabric of the present invention. [Diagram 5] FIG. 2 is an explanatory diagram for explaining a method for producing the crimped fiber used in the woven fabric of the present invention, and is an example of a form of a composite spinneret, showing a front cross-sectional view of a main part constituting the composite spinneret. [Figure 6] FIG. 2 is an explanatory diagram for explaining a method for producing crimped fibers used in the woven fabric of the present invention, and is a cross-sectional view of a portion of a distribution plate. [Figure 7] FIG. 2 is an explanatory diagram for explaining a method for producing crimped fibers used in the woven fabric of the present invention, and is a cross-sectional view of a discharge plate. [Figure 8] FIG. 2 is an explanatory diagram for explaining a method for producing crimped fibers used in the woven fabric of the present invention, and is a partially enlarged view of one embodiment of the arrangement of distribution holes in the final distribution plate. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0017] The present invention will now be described in detail with reference to preferred embodiments.

[0018] The woven fabric of the present invention is characterized by having excellent smoothness of surface irregularities while having stretchability, and it is important that, while being composed of crimped fibers, the fabric surface roughness (Ra) is 40 μm or less and the surface roughness CV% is 20% or less.

[0019] The surface roughness (Ra) of the fabric in the present invention is defined as the threshold value at which a person feels smooth when touching it with his / her skin, and it is important that this surface roughness is 40 μm or less. That is, the average size of the unevenness of human skin is several tens to several hundreds μm, and for example, it is said that the height of the unevenness of a fingerprint is 50 μm, and the length between the bumps is about 400 μm. The smoothness felt by the fingerprint is due to the friction between the finger and the fabric and the fluctuation when the finger is moved, and if the unevenness is 40 μm or less, which is sufficiently lower than the unevenness height of the fingerprint, the fingerprint does not feel resistance, and further, when the finger is moved, the fingerprint moves without being caught by the unevenness of the fibers and fabric structure present on the surface of the fabric, so that the surface is recognized as very smooth.

[0020] The fabric surface roughness (Ra) referred to here is an evaluation of the unevenness of the fabric surface in μm units, and is a value evaluated for the woven fabric of the present invention using a contact or non-contact surface roughness measuring instrument. In the measurement of the surface roughness, since the subject is a relatively soft woven fabric made of fibers, it is preferable to use a non-contact surface roughness measuring instrument, and the evaluation can be performed by the following method.

[0021] That is, the target woven fabric is prepared and placed on the sample stage so as to smooth out any creases. The surface of the woven fabric placed on the sample stage is photographed in 3D images with a field of view of 2 mm x 2 mm or more using a laser microscope (Keyence Corporation shape measurement laser microscope VK-X210). Five 3D images are photographed at any position on the woven fabric, and the surface roughness of each image is measured using an analysis application (VK-H1XA). The simple average is rounded off to the nearest whole number, and the surface roughness (Ra) of the fabric of the present invention is determined. The standard deviation is calculated from the measured values ​​of each image, and CV% is calculated as (standard deviation / average value) x 100. The value rounded off to the nearest whole number in percentage form is determined as the surface roughness CV% of the present invention.

[0022] The surface roughness CV% referred to here means the variation in the form of the woven surface, and in the present invention, it is important that this value is 20% or less. That is, by making this value sufficiently low, as described above, there is no variation in the touch, and by minimizing not only the size of the irregularities in the fabric surface roughness but also the variation, it is possible to achieve a very comfortable and smooth touch that is not found in conventional stretch materials, which is the object of the present invention.

[0023] By achieving a fabric surface roughness of 40 μm or less, the fabric can be used for everything from outerwear and mid-layers to pants, taking advantage of its smooth and pleasant texture. Combined with the excellent stretchability described below, the fabric can be used as a comfortable clothing textile for a wide range of applications, from sportswear to casual wear.

[0024] The woven fabric of the present invention can be used for shirts and blouses that often come into contact with human skin, taking advantage of its smooth texture. In order to appeal to the so-called comfort, it is better to enhance the texture, and from the viewpoint of enhancing the smoothness of the woven surface, it is preferable to further reduce the surface roughness of the fabric. Specifically, when used for shirts and blouses, the surface roughness of the present invention is preferably 30 μm or less. In this range, the woven surface has a significantly reduced unevenness compared to the unevenness of human skin, so that it is possible to realize a suitable wearing comfort without getting caught on human skin. In addition, from this viewpoint, in order to make the characteristics of the woven fabric of the present invention more prominent, it can be said that a lower surface roughness is preferable, and when used for innerwear that is constantly in contact with human skin, a surface roughness of 27 μm or less can be cited as a particularly preferable range. Furthermore, it is preferable that the fabric surface roughness CV% be low, which is one of the requirements of the present invention. However, as the surface roughness decreases, fluctuations in the fabric surface may become more pronounced. Therefore, when considering application to innerwear, it is particularly preferable that in addition to reducing the fabric surface roughness, the surface roughness CV% be 15% or less.

[0025] The fabric of the present invention has a weave selected from any one of plain weave (taffeta), twill, satin, pear-skin weave (amundsen), double weave, etc., or an application of these weaves, depending on the application and the part of use. In particular, in consideration of the characteristics of the present invention, it is preferable to select from any one of plain weave (taffeta), twill, satin, pear-skin weave (amundsen), or an application of these weaves.

[0026] In the present invention, in the woven fabric constructed with the above-mentioned weave structure, in addition to the surface properties, the fabric elongation percentage at a load of 14.7 N in at least one of the warp and weft directions must be 20% or more.

[0027] The fabric elongation rate referred to here is the elongation rate of a woven fabric sample measured under a load of 14.7 N according to Method A (constant rate elongation method) described in JIS L1096 (2010) 8.16. Five woven fabric samples of the same standard were prepared, and the same measurements were carried out for each sample. The values ​​were expressed as percentages and rounded off to the nearest whole number to determine the fabric elongation rate referred to in the present invention.

[0028] In the woven fabric of the present invention, it is important that the fabric elongation rate is 20% or more. This range means that the fabric can freely expand and contract according to the movement of the person, and even in areas with large movement such as elbows and knees, the textile is stress-free without being tight. Therefore, the woven fabric of the present invention is not only fully comfortable as an apparel material for town use such as slacks, business shirts, casual shirts, and jackets, but can also be developed as sports clothing with large movement. In particular, in outdoor clothing that requires intense movement in harsh environments, this characteristic effectively acts on comfort, so the higher the fabric elongation rate, the more preferable it is. In the study by the present inventors, the fabric elongation rate can be 25% or more as a preferable range. The fabric elongation rate can be controlled by appropriately adjusting the tissue density, etc., and it is preferable to change it depending on the part to be used, as it increases the comfort of the stretch clothing. From this viewpoint, it is better to increase the elongation rate in the elbow and knee regions, which are involved in the above-mentioned large movements, and it is particularly preferable to set the fabric elongation rate to 30% or more. According to this tendency, the higher the fabric elongation rate, the better, but considering the handling during sewing and the recovery during actual use, the substantial upper limit of the fabric elongation rate of the present invention is 100% or less.

[0029] The woven fabric of the present invention is a material that appeals to stretchability, and as described above, it has suitable properties as a relatively mobile clothing textile, but in terms of practical use, it is also necessary to consider the recovery of the fabric after stretching. From this perspective, it is preferable that the woven fabric of the present invention has an elongation recovery rate of 80% or more at a load of 14.7 N in at least one of the warp direction and weft direction. If it is within this range, the so-called "strawberry phenomenon" in which the stretched fabric does not recover partially becomes unlikely to occur, and in practical use, the fabric becomes unlikely to become sagging at the elbows and knees, which are subject to large movements.

[0030] The elongation recovery rate of the fabric referred to here is measured according to the C method described in JIS L1096 (2010) 8.16, after repeatedly applying and removing a load of 14.7 N five times. As with the fabric elongation rate, five woven fabric samples of the same standard were prepared and similar measurements were carried out for each sample. The values ​​were rounded off to the nearest whole number in percentage form to determine the elongation recovery rate referred to in the present invention.

[0031] The woven fabric of the present invention has a hysteresis (2HB) to stiffness (B) ratio (2HB / B) of 2.0 cm, as measured using a pure bending tester (KES-FB2) manufactured by Kato Tech. -1 Less than 1.5cm is preferable -1 The following is more preferred: This is a method for evaluating the resilience of fabrics, and the resilience can be calculated from the 2HB / B value, which is the ability to return to normal bending, based on the hysteresis (2HB) and stiffness (B) calculated from the hysteresis curve in bending characteristics. This value captures the energy loss in the process from bending deformation to recovery deformation as the amount of residual strain, and corresponds to the sensory evaluation of resilience, which can be quantified by the value of 2HB / B. In other words, this value can be taken as the residual strain in the process from bending deformation to recovery deformation. The smaller this residual strain, the better the resilience. Furthermore, stiffness (B) is an index of the hardness or softness of the fabric, and a smaller value means that the fabric is soft. This value is 0.010 gf cm 2 / cm or less is preferable, and 0.008 gf cm is more preferable. 2 / cm or less.

[0032] With the 2HB / B and B values ​​in the above ranges, the fabric has a moderate resilience and a soft feel, making it a comfortable clothing material.

[0033] Next, the crimped fibers constituting the woven fabric of the present invention will be described.

[0034] The crimped fibers constituting the woven fabric of the present invention are composite fibers made of fiber-forming polymers, and are preferably eccentric sheath-core fibers formed from two or more different types of polymers bonded together in an eccentric sheath-core configuration.

[0035] The fiber-formable polymer referred to in the present invention includes polyesters such as polyethylene terephthalate (PET), polyethylene naphthalate, polybutylene terephthalate (PBT), polytrimethylene terephthalate (PPT), etc., polyolefins such as polypropylene, polycarbonate, polyacrylate, polyamide, polylactic acid, thermoplastic polyurethane, polyphenylene sulfide, etc., and their copolymers.

[0036] In particular, polyester, polyamide, polyethylene, polypropylene, etc. are preferably used, and among them, polyester is more preferable because it also has mechanical properties, etc. The polyester referred to here includes polyethylene terephthalate, polybutylene terephthalate, polypropylene terephthalate, copolymerized with a dicarboxylic acid component, a diol component, or an oxycarboxylic acid component, or a blend of these polyesters. In addition, aliphatic polyesters such as polylactic acid, polybutylene succinate, and polyε-caprolactam, which are known as biodegradable polyesters, may also be used.

[0037] The crimped fibers constituting the woven fabric of the present invention are made into final products through various advanced processing steps after spinning. Therefore, taking into consideration the processing temperatures in these steps, it is preferable that the fiber-forming polymer used is a polymer with good heat resistance and a melting point of 165°C or higher, and among these, polyester-based polymers such as polyethylene terephthalate, polybutylene terephthalate, and polytrimethylene terephthalate and polyamide-based polymers are preferable. In particular, polyethylene terephthalate can be preferably used from the viewpoint of appropriate resilience and firmness. Furthermore, these fiber-formable polymers may contain various additives, such as inorganic substances such as titanium oxide, silica, barium oxide, etc., colorants such as carbon black, dyes, and pigments, flame retardants, fluorescent brighteners, antioxidants, or ultraviolet absorbers, as long as the additives do not impair the object of the present invention.

[0038] In addition, with attention being paid to environmental issues, the use of plant-derived biopolymers and recycled polymers in the present invention is also preferable from the viewpoint of reducing the environmental load, and the polymer used in the present invention described above can be a recycled polymer recycled by any of the methods of chemical recycling, material recycling, and thermal recycling. Even when a biopolymer or recycled polymer is used, the polyester resin can accentuate the features of the present invention as its polymer characteristics, and recycled polyester can be preferably used in the present invention.

[0039] The crimped fibers constituting the woven fabric of the present invention are preferably made of two different polymers bonded in a thin-skin eccentric sheath-core structure. This means that two or more polymers with different polymer properties are present in a bonded state without being substantially separated, and any composite form in which two polymers are bonded can be used, such as an eccentric sheath-core structure in which one component is covered by the other component as seen in general composite fibers, in which the core component is biased.

[0040] The state in which the two types of polymers forming the crimped fibers constituting the woven fabric of the present invention are bonded together without being substantially separated means that the core component polymer A (hereinafter, component A) and the sheath component polymer B (hereinafter, component B) are bonded together with a bonding surface, and therefore the components A and B exist together as one unit without peeling off.

[0041] As the polymers that form a composite structure in which two different types of polymers are bonded to form the crimped fibers that make up the woven fabric of the present invention, a combination of polymers that cause a difference in shrinkage when subjected to heat treatment is preferred, and a combination of polymers with different molecular weights or compositions that result in a difference in melt viscosity of 10 Pa s or more is preferred.

[0042] The melt viscosity in the present invention is measured by adjusting the moisture content of a chip-shaped polymer to 200 ppm or less using a vacuum dryer, changing the strain rate stepwise, and measuring the melt viscosity at a strain rate of 1216 s when the measurement temperature is the same as the spinning temperature. -1 The melt viscosity difference is the value at 10 Pa·s. If the melt viscosity difference between the polymers constituting the fiber is 10 Pa·s or more, for example, stress will be concentrated on the polymer component with the higher melt viscosity at the spinning line. Therefore, in the case of a core-sheath type cross section or an island-in-the-sea type cross section, stress will be concentrated on the main polymer, resulting in excellent mechanical properties, and in the case of a laminated type cross section, a significant difference will be created depending on the orientation of the combined components, making it possible to develop suitable crimp. Considering the development of crimp, etc., it is preferable that the melt viscosity difference between the combined polymers is larger, and a melt viscosity difference of 50 to 400 Pa·s is a preferred range. Although it is preferable to increase the melt viscosity difference, in the present invention, considering the development of characteristics and the difference in elongation deformation at the spinning line that can be controlled, a melt viscosity difference of 100 to 300 Pa·s is a particularly preferred range.

[0043] In the crimped fiber constituting the woven fabric of the present invention, the composite area ratio in the fiber cross section of component A and component B is such that, in terms of crimp expression, a fine spiral structure can be realized by increasing the ratio of the high shrinkage component, component A. In addition, since it is necessary for the eccentric core-sheath composite fiber to have excellent physical properties, the ratio of both components, component A:component B, is preferably in the range of 70:30 to 30:70 (area ratio), and more preferably in the range of 65:35 to 45:55.

[0044] In the present invention, it is preferable that the crimped fibers constituting the woven fabric have a composite cross section formed by bonding two different polymers, that the two polymers with different polymer properties are present in a bonded state without being substantially separated, and that the A component is completely covered by the B component, being an eccentric core-sheath type.

[0045] Here, the eccentricity referred to in the present invention means that the position of the center of gravity of component A in the cross section of the composite fiber is different from the center of the cross section of the composite fiber, and will be explained with reference to FIG.

[0046] In FIG. 2, the horizontal hatching is component B, the 30 deg hatching (diagonal lines rising to the right) is component A, the center of gravity of component A in the cross section of the composite fiber is center of gravity a, and the center of gravity of the cross section of the composite fiber is center point b.

[0047] In the present invention, it is important that the center of gravity a and the center b are far apart, so that the fiber will bend significantly toward the high shrinkage component after heat treatment. As a result, the composite fiber continues to bend in the fiber axis direction, forming a three-dimensional spiral structure and exhibiting good crimp. Here, the farther apart the center of gravity is, the better the crimp will be, and the better the stretch performance will be.

[0048] In the present invention, because component A is completely covered by component B, even if the fibers or fabric are subjected to friction or impact, whitening or fluffing does not occur, and the quality of the fabric can be maintained. In addition, high molecular weight polymers and highly elastic polymers, which are exposed on the surface and cause defects in composite fibers in the conventional simple lamination structure, can be used as one component of the composite fiber.

[0049] In addition, since one component A is completely covered by the other component B, it is possible to have the effect of maintaining good fiber properties even when using, for example, a polymer with low heat resistance or abrasion resistance, or a hygroscopic polymer.

[0050] The eccentric core-sheath composite fiber, which is the crimped fiber constituting the woven fabric of the present invention that achieves the above effects, preferably has a ratio S / D of 0.01 to 0.1, where S is the minimum thickness of the B component covering the A component, and D is the diameter of the composite fiber. If the ratio is within this range, the deterioration of the fabric quality due to fluff, etc. can be suppressed, and sufficient crimp development and stretch performance can be obtained. Here, the crimped fiber can obtain good stretch performance because the respective polymers are originally in contact only at the bonding interface, and if the high shrinkage component is covered by the low shrinkage component, the stretch performance decreases. However, as a result of intensive research by the present inventors, it has become possible to obtain a composite fiber that satisfies both the stretch performance and the abrasion resistance by setting the thickness of the B component, which is the sheath component, within the range of the present invention.

[0051] This will be explained in more detail using the fiber cross section shown in Figure 3. Here, the thinnest part of the B component in the core-sheath composite fiber has a minimum thickness S.

[0052] Furthermore, it is important that the part of the thickness within 1.05 times the minimum thickness S occupies 1 / 3 or more of the total perimeter of the composite fiber. This means that the component A is present along the contour of the fiber, and compared to conventional eccentric core-sheath composite fibers with the same area ratio, the present invention has the center of gravity of each component farther apart in the fiber cross section, forming a fine spiral and exhibiting good crimp. More preferably, by making the perimeter of the part of the thickness within 1.05 times the minimum thickness 2 / 3 or more of the total perimeter of the fiber, good stretch performance can be obtained without crimp unevenness. Furthermore, since the spiral structure of each fiber when crimp is exhibited is uniform, sufficient stretch performance can be obtained without fineness unevenness, and a fabric with a good appearance without wrinkles or streaks and a smooth and delicate texture can be obtained.

[0053] Furthermore, when the radius of curvature of the interface between components A and B in the fiber cross section is IFR and the fiber diameter D is divided by 2 to give R, it is preferable that the following formula 1 is satisfied. (IFR / R)≧1···(Formula 1) The radius of curvature IFR here refers to the radius of the circle (dashed line) tangent to the curvature of the interface between components A and B, which is the maximum thickness of component B covering component A in the cross section of the fiber, as shown in Figure 4.

[0054] This means that the interface is closer to a straight line. The present invention is preferable because it makes it possible to achieve high crimping that was not possible with conventional eccentric core-sheath composite fibers by making the interface between components A and B a curve close to a straight line in a form similar to the cross section of conventional bonded crimped yarns.

[0055] The minimum thickness S of component B covering component A, fiber diameter D, interface curvature radius IFR, and area ratio are calculated as follows:

[0056] That is, a multifilament made of eccentric core-sheath composite fibers is embedded in an embedding agent such as epoxy resin, and an image of the cross section is taken with a transmission electron microscope (TEM) at a magnification where 10 or more fibers can be observed. In this case, if metal dyeing is applied, the contrast of the joint between the A component and the B component can be made clear by utilizing the dyeing difference between the polymers. The value obtained by measuring the circumscribed circle diameter of 10 fibers randomly extracted from each image taken corresponds to the fiber diameter D referred to in the present invention. Here, if it is impossible to observe 10 or more fibers, it is sufficient to observe a total of 10 or more fibers including other fibers. The circumscribed circle diameter referred to here means the diameter of a true circle that circumscribes the most at two or more points on a cross section perpendicular to the fiber axis of a two-dimensionally taken image.

[0057] In addition, the image in which the fiber diameter D was measured is used to measure the minimum thickness of component B covering component A for 10 or more fibers, and the value corresponds to the minimum thickness S referred to in the present invention. Furthermore, the fiber diameter D, minimum thickness S, and radius of curvature IFR are measured in units of μm, and are rounded off to the nearest third decimal place. The simple number average of the measured values ​​and their ratios (S / D) is calculated for 10 images photographed after the above operations.

[0058] In addition, the area ratio is calculated by using the image captured as described above and image analysis software, such as "WinROOF2015" manufactured by Mitani Shoji Co., Ltd., to determine the area of ​​the entire fiber and the areas of components A and B, and then calculating the area ratio.

[0059] The crimped fibers constituting the woven fabric of the present invention preferably have a stretch elongation rate as measured by JIS L1013 (2010) Section 8.11, Method C (simplified method) of 40% or more. More preferably, it is 55% or more. This value indicates the degree of crimp, and the higher the value, the better the stretch performance.

[0060] The crimped fibers constituting the woven fabric of the present invention preferably have a Worcestershire unevenness (U%), which is an index of unevenness in the longitudinal direction of the fiber, i.e., unevenness in fineness, of 1.5% or less. This not only prevents uneven dyeing of the fabric, but also prevents deterioration of the fabric quality due to uneven shrinkage, and allows good fabric quality to be obtained. More preferably, it is 1.0% or less.

[0061] The single fiber fineness of the crimped fiber constituting the woven fabric of the present invention is preferably 3.0 dtex or less. This allows the fabric to have appropriate stretch performance, resilience, and softness. In addition, this, combined with the fine spiral structure due to the crimping performance of the eccentric core-sheath composite fiber of the present invention, results in a dense fabric surface, resulting in a stretch material with an unprecedented smooth and delicate feel. It is further preferably 2.0 dtex or less, and more preferably 1.0 dtex or less.

[0062] The degree of irregularity of the fiber cross section of the crimped fiber constituting the woven fabric of the present invention is preferably 1.0 to 1.5. The degree of irregularity referred to here is determined as follows. That is, an image of the crimped fiber is taken at a magnification where 10 or more fibers can be observed. The diameter of a perfect circle circumscribing the cross section perpendicular to the fiber axis from this two-dimensionally taken image is taken as the circumscribing diameter, and the diameter of the perfect circle that is inscribed most frequently at two or more points on this cross section is taken as the inscribing diameter. The degree of irregularity is determined by calculating the formula "degree of irregularity = circumscribing diameter / inscribing diameter" to the second decimal place and rounding off the whole number to the nearest tenth place. The above operation is performed on 10 images, and the simple number average of the values ​​measured for each image is taken to determine the degree of irregularity of the crimped fiber of the present invention. Incidentally, in the degree of irregularity referred to in the present invention, 1.0 corresponds to a perfect circle, and an increase in the value means that the cross section of the fiber is more deformed.

[0063] The fiber cross section of the crimped fiber constituting the woven fabric of the present invention can be selected from any shape, but a round shape is preferable for the following reasons. In addition, a hollow cross section structure is likely to be crushed during the dyeing process, which tends to cause variation in the degree of irregularity, so a substantially solid cross section structure is preferable. Furthermore, fibers constituting stretch woven fabrics are generally often subjected to false twist processing, but this processing is not preferable because it causes significant cross section deformation, the degree of irregularity exceeds 1.5, the coil shape of the crimp is destroyed, and a messy coil shape is formed, which roughens the fabric surface.

[0064] In addition, in order to overcome the fabric restraint force and stably develop crimp, the shrinkage stress and the temperature at which the shrinkage stress reaches its maximum value are important characteristics. The higher the shrinkage stress, the better the shrinkage under fabric restraint, and the higher the temperature at which the shrinkage stress reaches its maximum value, the easier it is to handle in the finishing process. Therefore, in order to further enhance the development of crimp, the temperature at which the shrinkage stress reaches its maximum value is preferably 110°C or higher, more preferably 130°C or higher, and the maximum value of the shrinkage stress is preferably 0.15cN / dtex or higher, more preferably 0.20cN / dtex. In order to generate the shrinkage stress as described above, it is possible to carry out the spinning and drawing under specific conditions, and it is also preferable to use a high shrinkage polymer that easily shrinks when heated as one of the polymers used for the fiber. For example, a copolyester in which a third component such as isophthalic acid or bisphenol A (2·2-bis{4-(2-hydroxyethoxy)phenyl}propane) is copolymerized with polyethylene terephthalate is preferable.

[0065] Considering the processability in advanced processing and practical use, it is preferable that the crimped fiber constituting the woven fabric of the present invention has a certain level of toughness, and the strength and elongation of the fiber can be used as indicators. The strength here is the value obtained by dividing the load value at break by the initial fineness when the load-elongation curve of the fiber is obtained under the conditions specified in JIS L1013 (2010), and the elongation is the value obtained by dividing the elongation at break by the initial test length. In addition, the initial fineness means the value calculated as the weight per 10,000 m from the simple average value obtained by measuring the weight of a unit length of the fiber multiple times.

[0066] The crimped fiber constituting the woven fabric of the present invention preferably has a strength of 0.5 to 10.0 cN / dtex and an elongation of 5 to 700%. In the crimped fiber of the present invention, the upper limit of the feasible strength is 10.0 cN / dtex and the upper limit of the feasible elongation is 700%. When the crimped fiber constituting the woven fabric of the present invention is used for general clothing applications such as innerwear and outerwear, the strength is preferably 1.0 to 4.0 cN / dtex and the elongation is preferably 20 to 40%. When the crimped fiber is used for sports clothing applications in harsh environments, the strength is preferably 3.0 to 5.0 cN / dtex and the elongation is preferably 10 to 40%.

[0067] As described above, in the fiber of the present invention, it is preferable to adjust the strength and elongation by controlling the conditions of the production process according to the intended use, etc.

[0068] The elastic modulus of the crimped fibers constituting the woven fabric of the present invention is preferably 70 cN / dtex or more. More preferably, it is 75 cN / dtex or more. The elastic modulus of the crimped fibers can be controlled to some extent by, for example, the type and fineness of the raw yarn, the filament configuration, the stretching conditions, the intertwining conditions, the additional twist conditions, etc., but it is the main factor that determines the texture such as softness and resilience when the woven fabric is formed. By making the elastic modulus 70 cN / dtex or more, a resilience can be obtained even with a fine fineness, and the softness due to the fineness and the appropriate resilience and firmness can be maintained. As a preferable combination of different polymers to achieve this, it is preferable that all of them are polyethylene terephthalate or its copolymer. In order to obtain the desired stretchability, it is preferable to combine polyethylene terephthalates with different shrinkage characteristics by changing the molecular weight or copolymerization component.

[0069] Next, a preferred method for producing the crimped fibers constituting the woven fabric of the present invention will be described.

[0070] The crimped fibers constituting the woven fabric of the present invention can be produced by any process, such as a two-step process in which the extruded polymer is once wound up as an undrawn yarn and then drawn, a direct spinning-drawing process in which spinning and drawing steps are carried out continuously, or a high-speed spinning process. In addition, since the range of the spinning speed in the high-speed spinning process is not particularly specified, a drawn yarn may be obtained by a step of winding the extruded polymer as a semi-drawn yarn and then drawing it.

[0071] In addition, the above-mentioned crimped fibers can be given a real twist according to the use of the woven fabric, which can provide a suitable resilience and easily produce fine coil crimps when the crimp occurs, and can fill the voids in the woven fabric more effectively, resulting in a stable coil shape, a smooth fabric surface, and excellent stretch recovery, which is preferable. The preferred number of twists is 500 to 2500 T / M, and more preferably 1000 to 2000 T / M. On the other hand, false twist processing is not preferable because it deforms the fiber cross section, destroys the coil shape of the crimp, forms a messy coil shape, and roughens the fabric surface.

[0072] When the crimped fibers constituting the woven fabric of the present invention are spun by a two-step method, any known drawing method can be used, including hot roll-hot roll drawing and drawing using a hot pin. Depending on the application, drawing may be performed while adding entanglement, etc. In order to suppress compound abnormalities such as fuzz generation and peeling of both components, it is preferable to draw the drawn yarn so that the residual elongation is 25 to 50%.

[0073] When the fiber is heat-set in a stretched state and cooled to below the glass transition temperature while maintaining tension to fix the molecular chain structure, the shrinkage stress can be increased, which is effective in improving the texture of the fabric. Specifically, it is preferable to pass the fiber through a cold roll while it is stretched by about 0.3 to 3.0%, since a high shrinkage stress can be obtained. In addition, since the fiber is spun and wound in a state in which a stress strain is applied to the polymer side (for example, the component A of the present invention) that shrinks to express crimp, delayed shrinkage occurs due to viscoelastic behavior before the fabric is formed after winding, and streaks may be formed in the fabric. On the other hand, in the present invention, delayed shrinkage can be suppressed by completely covering one component with the other component, which can also contribute to obtaining a uniform fabric. Furthermore, it is possible to use high molecular weight polymers and high elasticity polymers that could not be used so far as high shrinkage components, and it is also possible to obtain new core-sheath composite fibers.

[0074] The spinning temperature is preferably set at a temperature higher than the polymer melting point by +20 to +50° C. Setting the temperature at a temperature higher than the polymer melting point by +20° C. or more can prevent the polymer from solidifying and clogging the spinning machine piping, and setting the higher temperature to +50° C. or less can suppress excessive thermal degradation of the polymer, which is preferable.

[0075] The crimped fibers constituting the woven fabric of the present invention are preferably eccentric core-sheath composite fibers, and are preferably obtained by a melt spinning method. The spinneret may have any known internal structure as long as it is capable of spinning with stable quality and operation. In particular, distributor plate type spinnerets exemplified in JP-A-2011-174215, JP-A-2011-208313, and JP-A-2012-136804 are preferably used to form the desired cross-sectional shape.

[0076] Here, it is preferable that the eccentric core-sheath composite fiber of the present invention completely covers the A component with the B component as shown in FIG. 1. The cross section of the present invention can suppress bending of the discharge line (kneeing phenomenon) caused by the difference in flow speed of two types of polymers when discharged from the spinneret. In addition, in the case of a conventional simple laminated structure (bimetal structure), a difference occurs in the balance of stress applied to each polymer during thinning on the spinning line after discharge from the spinneret, causing unevenness in elongation deformation, which manifests as uneven fineness and increases U%. This tendency is very noticeable when combining polymers with a large viscosity difference or when thinning is achieved by reducing the discharge amount, but in the present invention, the stress balance is balanced in the fiber cross section by covering with one of the polymers, and uneven fineness can be suppressed. Furthermore, it has been found that when a high molecular weight polymer is used as the A component and a low molecular weight polymer is used as the B component, the complete coverage of the A component provides excellent high-speed spinning stability. This is the effect of the low molecular weight polymer being arranged on the outside, making it easier for the high molecular weight polymer to follow the elongation deformation after discharge from the spinneret.

[0077] This dramatically increases the freedom to select polymers to improve added value other than stretch performance and yarn reeling stability, even for fine yarns, and also contributes to improved productivity.

[0078] As described above, by adopting the cross-sectional shape of the present invention, unevenness in fineness can be suppressed.

[0079] In this case, a spinning draft of 300 times or less is preferable because it is possible to obtain homogeneous fibers with suppressed variations in physical properties among the filaments. The number of filaments can be appropriately set depending on the size of the spinneret, but it is preferable to keep the spacing between the filament discharge holes at 10 mm or more because this allows the filaments to be cooled and solidified smoothly, making it easier to obtain homogeneous fibers.

[0080] The spinning draft of the eccentric core-sheath composite fiber, which is the crimped fiber constituting the woven fabric of the present invention, represented by the following formula, is preferably 50 to 300. Spinning draft = Vs / V0 Vs: spinning speed (m / min) V0: Discharge linear velocity (m / min) By setting the spinning draft at 50 or more, the polymer flow discharged from the spinneret hole is prevented from remaining directly below the spinneret for a long time, and the spinneret surface can be prevented from being soiled, resulting in stable spinnability. In addition, by setting the spinning draft at 300 or less, it is possible to prevent yarn breakage due to excessive spinning tension, and eccentric core-sheath composite fibers can be obtained with stable spinnability, which is preferable. The spinning draft is more preferably 80 to 250.

[0081] The spinning tension of the eccentric sheath-core composite fiber, which is the crimped fiber constituting the woven fabric of the present invention, is preferably 0.02 to 0.15 cN / dtex. By setting the spinning tension at 0.02 cN / dtex or more, there is no yarn interference between single yarns due to yarn swaying during spinning, and the yarn is not reversely wound around the first roller, i.e., the take-up roller, allowing stable running. In addition, it is preferable to set the spinning tension at 0.15 cN / dtex or less, since this allows eccentric sheath-core composite fiber to be obtained stably in spinning. The more preferred range of the spinning tension is 0.07 to 0.1 cN / dtex.

[0082] In order to spin the eccentric sheath-core composite fiber, which is the crimped fiber constituting the woven fabric of the present invention, with stable operation and quality, it is preferable to strictly control the cooling and solidification of the discharged polymer. If the amount of discharged polymer is suppressed as the fiber size is reduced, the polymer is thinned and cooled and solidified, moving upstream, so that only fibers with many yarn irregularities in the longitudinal direction can be obtained by the cooling method assumed in the conventional technology. In addition, the accompanying air flow due to the solidified fiber increases, and the spinning tension increases, so a technology to reduce these is required. As a method for reducing the increase in spinning tension, it is preferable to set the cooling start point 20 to 120 mm from the spinneret surface. If the cooling start point is 20 mm or more, the decrease in the surface temperature of the spinneret due to the cooling air can be suppressed, and various problems such as low-temperature yarn, clogging of the spinneret hole, composite abnormality, and discharge irregularity can be avoided, which is preferable. In addition, it is preferable to set the cooling start point to 120 mm or less, because it is possible to obtain high-quality eccentric sheath-core composite fiber with little yarn irregularities in the longitudinal direction. A more preferable range of the cooling start point is 25 to 100 mm.

[0083] In order to prevent a drop in the temperature of the nozzle surface due to the cooling air, the temperature of the cooling air may be controlled as necessary, or a heating device may be installed around the nozzle.

[0084] The distance from the nozzle discharge surface to the oil supply position is preferably 1300 mm or less. By setting the distance from the nozzle discharge surface to the oil supply position to 1300 mm or less, the width of yarn sway caused by cooling air can be suppressed, yarn unevenness in the fiber longitudinal direction can be improved, and the accompanying airflow until the yarn converges can be suppressed, so that the spinning tension can be reduced and stable spinnability with less fuzz and yarn breakage can be easily obtained, which is preferable. A more preferable range for the oil supply position in the spinning process of eccentric core-sheath composite fibers is 1200 mm or less.

[0085] To obtain the woven fabric of the present invention, a known loom suitable for the desired weave can be selected. Examples include shuttle looms, rapier looms, air jet looms, water jet looms, etc. The shedding device can be appropriately selected from tappet type, dobby type, jacquard type, etc., depending on the weave of the fabric.

[0086] After weaving, the fabric can be treated by known methods, such as scouring, alkali treatment, relax heat treatment, intermediate setting treatment, dyeing treatment, finishing treatment, etc. In the relax heat treatment, an open soaper is used, the submerged temperature is set to about 60°C, and the fabric is gradually shrunk, making it possible to prevent the fabric from becoming wrinkled or wrinkled. EXAMPLES

[0087] The stretch fabric of the present invention will be described in detail below with reference to examples. The examples and comparative examples were evaluated as follows.

[0088] (1) Melt viscosity of polymer The chip-shaped polymer was dried in a vacuum dryer to a moisture content of 200 ppm or less, and the melt viscosity was measured by changing the strain rate stepwise using a Capillograph 1B made by Toyo Seiki. The measurement temperature was the same as the spinning temperature, and the melt viscosity of 1216 s-1 is recorded in the examples and comparative examples. Incidentally, the time from putting the sample into the heating furnace to the start of the measurement was 5 minutes, and the measurement was performed under a nitrogen atmosphere.

[0089] (2) Fineness Using a measuring machine with a frame circumference of 1.0 m, 100 skeins were prepared and the fineness was measured according to the following formula. This was repeated 10 times, and the simple average value was rounded off to the nearest whole number to obtain the fineness. Fineness (dtex) = Weight of skein for 100 uses (g) x 100 This measurement was repeated 10 times, and the simple average value was rounded off to the nearest whole number to obtain the fineness.

[0090] (3) Fiber strength, breaking elongation, toughness, elastic modulus, stretch elongation rate The samples were measured using a tensile tester (Orientec "TENSILON" UCT-100) under the constant speed elongation conditions specified in JIS L1013 (2010) 8.5.1 standard time test. The gripping distance was 20 cm, the pulling speed was 20 cm / min, and the number of tests was 10. The breaking elongation was calculated from the elongation at the point showing the maximum strength on the SS curve. The elastic modulus was determined as the initial tensile resistance according to JIS L1013 (2010) 8.10. The toughness was calculated from the following formula. Toughness = Strength (cN / dtex) × √(Elongation (%)) The fiber stretching and elongation rates were determined according to JIS L1013 (2010) Clause 8.11, Method C (simplified method) for fiber samples that had been treated at 90°C for 20 minutes prior to measurement. For each value, these procedures were repeated five times for each level, and the simple average of the results was calculated. Strength was rounded to one decimal place, and breaking elongation, toughness, elastic modulus, and stretching and elongation rates were rounded to the nearest whole number.

[0091] (4) U% Using a Zellweger UT-4 fineness unevenness measuring device, U%(H) was measured under the conditions of a yarn supply speed of 200 m / min, a twister rotation speed of 20,000 rpm, and a measurement length of 200 m. This measurement was repeated 10 times, and the simple average value was rounded off to the first decimal place to obtain U%.

[0092] (5) Shrinkage stress Measurements were taken at a heating rate of 150°C / min using an Intec (formerly Kanebo Engineering) KE-2S thermal stress measuring device. The sample was 0.1m x 2 loops, and the initial tension was set to fineness (dtex) x 0.03cN. The temperature at which the shrinkage stress reached its maximum value was the maximum temperature (°C). This measurement was repeated 10 times, and the simple average values ​​were calculated by rounding off the third decimal place for stress and the decimal place for maximum temperature.

[0093] (6) Degree of irregularity The crimped fiber was cut at an arbitrary position in the fiber axis direction, and the fiber cross section was photographed with a Hitachi scanning electron microscope (SEM) at a magnification where 10 or more single yarns of each cross section shape could be observed, and the diameter of the true circle inscribed in the cut surface of each cross section was defined as the inscribed circle diameter, and the diameter of the true circle circumscribed around the cut surface was defined as the circumscribed circle diameter, and the irregularity was calculated as circumscribed circle diameter / inscribed circle diameter. This operation was performed at 10 places for each cross section, and the simple average of the results obtained was rounded off to the nearest tenth place.

[0094] (7) Fabric surface roughness (Ra) The target woven fabric is prepared and placed on a sample stage so as to smooth out any creases. A 3D image of the surface of the woven fabric placed on the sample stage is taken with a laser microscope (Keyence Corporation, shape measuring laser microscope VK-X210) with an observation field of view of 2 mm x 2 mm or more. Five 3D images are taken at any position on the fabric, and the surface roughness of each image is measured using an analysis application (VK-H1XA). The simple average is rounded off to the nearest whole number to determine the surface roughness (Ra) of the fabric of the present invention. The standard deviation is calculated from the measured values ​​of each image, CV% = (standard deviation / average value) x 100 The surface roughness CV% of the present invention was calculated as follows: and the value was rounded off to the nearest whole number in percent.

[0095] (8) Elongation rate of fabric (woven fabric) According to the method A (constant rate extension method) described in JIS L1096 (2010) 8.16, the extension rate was measured at a load of 14.7 N. This measurement was repeated 10 times, and the simple average value was rounded off to the nearest whole number.

[0096] (9) Elongation recovery rate of fabric (fabric) According to the C method described in JIS L1096 (2010) 8.16, the elongation recovery rate was measured after repeatedly applying and removing a load of 14.7 N 5 times. This measurement was repeated 10 times, and the simple average value was rounded off to the nearest whole number.

[0097] (10) Fabric resilience (2HB / B), rigidity (B) The obtained woven fabric was refined, alkali-treated, and heat-set to evaluate the resilience. The resilience can be calculated from the hysteresis (2HB) and stiffness (B) obtained from the hysteresis curve in the bending characteristics of a Kato Tech pure bending tester (KES-FB2), and the value of 2HB / B can be used to calculate the resilience. This value captures the energy loss in the process of bending deformation and recovery deformation as the amount of residual strain, and corresponds to the sensory evaluation of resilience, which can be quantified by the value of 2HB / B. In other words, this value can be taken as the residual strain in the process of bending deformation and recovery deformation. The smaller the residual strain, the better the resilience. Also, the smaller the value of B, the softer the material is.

[0098] The relationship between the 2HB / B value and the repulsive sensation based on sensory evaluation was examined, and a high repulsive sensation was obtained at 1.5cm. -1 Less than 1.5cm is enough to give a sense of resilience. -1 More than 2.0cm -1 Less than 2.0cm is considered to be ○, and the rebound feeling is considered to be insufficient. -1 The above points were marked as "X" and rated on a three-point scale.

[0099] In addition, the relationship between the value of B and softness evaluated by the sensory evaluation was examined, and the softest perceived value was 0.008 gf cm 2 / cm is less than 0.008gf·cm for a relatively soft feel. 2 / cm or more 0.010gf·cm 2 / cm is OK, and 0.010gf cm is hard. 2 This measurement was repeated 10 times, and the simple average values ​​were rounded off to one decimal place for the resilience (2HB / B) and to three decimal places for the stiffness (B).

[0100] The sensory evaluation was performed by five experienced examiners. High evaluations by all five examiners were marked with an ⊚, high evaluations by 2 to 4 examiners with an ◯, and high evaluations by 1 or less examiners with an ×.

[0101] Example 1 The A component was copolymerized polyethylene terephthalate (co-PET, polyethylene terephthalate copolymerized with 7.0 mol% isophthalic acid and 4 mol% 2·2-bis{4-(2-hydroxyethoxy)phenyl}propane, melt viscosity: 110 Pa·s), and the B component was polyethylene terephthalate (PET1, melt viscosity: 70 Pa·s). Both the A component polymer and the B component polymer were melted at 270°C and 280°C, respectively, using an extruder, and then metered with a pump. The spinning temperature was set to 290°C, which is 30°C higher than the melting point of the B component, which has the highest melting point of each polymer, and the temperature was maintained at this temperature. The weight ratio of the A component and the B component was 50 / 50, and the components were fed into a spinneret for eccentric core-sheath composite fibers with 72 discharge holes. The polymers merged inside the spinneret to form an eccentric core-sheath composite form in which the A component polymer was contained in the B component polymer, and the resulting product was discharged from the spinneret. In the spinning of Example 1, a spinneret of the distributor plate type was used so as to obtain the eccentric core-sheath composite fiber shown in FIG.

[0102] The yarn discharged from the spinneret was cooled by an air-cooling device, oiled, and then wound up by a winder at a speed of 1000 m / min so that the spinning draft was 220, and stably wound up as an undrawn yarn of 165 dtex-72 filaments. At this time, the cooling start point was set to 97 mm from the spinneret discharge surface, and the oil supply position was set to 1130 mm from the spinneret discharge surface, resulting in a spinning stress of 0.10 cN / dtex, suppressing longitudinal yarn unevenness and stabilizing spinnability.

[0103] The undrawn yarn was then fed to a drawing device at a speed of 600 m / min, and drawn at a draw ratio of 2.92 times to give a drawing temperature of 90°C and an elongation of approximately 20-40%, after which it was heat-set at 130°C. A 56 dtex-72 filament drawn yarn was obtained that had a stably strength of 3.4 cN / dtex, an elongation of 34%, and a degree of irregularity of 1.0 throughout the spinning and drawing processes.

[0104] The evaluation results of the obtained eccentric sheath-core composite fiber are shown in Table 1. The S / D ratio in the fiber cross section was 0.02, and the minimum thickness portion accounted for 40% of the fiber circumference. The stretch extension ratio, which is an index of the stretch performance of the eccentric sheath-core composite fiber, was 45%, and the fiber morphology was bulky with fine crimps.

[0105] The drawn yarn was then twisted at 1300T / M using a double twister, and the yarn was then used as the warp and weft to form a plain weave using an air jet loom. The woven fabric was then subjected to continuous spread scouring at 98°C, liquid flow relaxation at 130°C, intermediate setting at 180°C, and navy blue dyeing at 130°C using a disperse dye, and further to a finish setting at 160°C to produce a product with a processed density (warp: 170 threads / 2.54 cm, weft: 130 threads / 2.54 cm).

[0106] The fabric obtained in Example 1 was a uniform fabric of high quality without wrinkles or streaks, and the fabric elongation rate was 18% in the warp direction and 24% in the weft direction, and the fabric elongation recovery rate was 94% in the warp direction and 93% in the weft direction, resulting in a fabric with excellent stretch performance.

[0107] The resulting woven fabric had a surface roughness (Ra) of 26 μm and a surface roughness CV% of 8%, and the fabric surface had a smooth feel due to the fine and uniform crimping.

[0108] The stiffness and resilience of the resulting fabric were evaluated. -1 It has a high resilience, and in terms of rigidity, it feels even softer at 0.007 gf·cm2 / cm, making it a woven fabric with a comfortable resilience while still having just the right amount of flexibility.The surface also feels smooth and comfortable to the touch, making it a stretch fabric. The results are shown in Table 1.

[0109] [Table 1]

[0110] Examples 2 and 3, Comparative Example 1 Examples 2 and 3 and Comparative Example 1 were carried out in the same manner as Example 1, except that the number of discharge holes in the spinneret was changed as shown in Table 1, and the single fiber fineness was changed.

[0111] In both Examples 2 and 3, similar to Example 1, comfortable stretch fabrics were obtained that were smooth and had both a resilient feel and softness.

[0112] However, in Comparative Example 1, in which the single fiber fineness was large, the unevenness of the woven surface was apparent from the appearance, and the tactile evaluation showed that the smoothness was reduced compared to Example 1, and furthermore, the flexibility was reduced due to the increased rigidity. The results are shown in Table 1.

[0113] Example 4 The same operations as in Example 1 were performed except that the component A polymer was changed to high molecular weight polyethylene terephthalate (PET2: melt viscosity: 160 Pa·s).

[0114] The fabric of Example 4 was slightly inferior in softness compared to Example 1, but had sufficiently excellent properties compared to conventional materials and was without any problems. A comfortable stretch fabric was obtained that was smooth, resilient, and soft. The results are shown in Table 1.

[0115] Comparative Example 2 As shown in Table 1, the same procedure as in Example 1 was carried out except that the polymer of component A in Example 1 was high molecular weight polyethylene terephthalate (PET2: melt viscosity: 160 Pa·s) and the single fiber fineness was 4.6 dtex.

[0116] The obtained woven fabric had a rough surface and was inferior in smoothness due to the thicker single fiber fineness, as in Comparative Example 1, and had high rigidity and was inferior in softness due to the thicker single fiber fineness. The results are shown in Table 1.

[0117] Comparative Example 3 A fabric was obtained in the same manner as in Example 1, except that the component A polymer in Example 1 was changed to polybutylene terephthalate (PBT, melt viscosity 160 Pa·s).

[0118] When the surface of the woven fabric was evaluated, the surface roughness was 45 μm and the surface roughness CV% was 35%, which was clearly different from the fabric obtained in Example 1 and was inferior in smoothness. In addition, although the fabric had a soft texture, the resilience was lower than that of Example 1, and the value was 2.5 cm -1 The results are shown in Table 1.

[0119] Examples 5 and 6 The same procedure as in Example 1 was carried out except that the number of twists was changed as shown in Table 1.

[0120] The obtained fabric had a slightly different surface roughness compared to Example 1, but it was a comfortable stretch fabric that was smooth and had both a resilient feel and softness, just like Example 1. The results are shown in Table 1.

[0121] Comparative Example 4 The component A polymer in Example 1 was polytrimethylene terephthalate (3GT, melt viscosity 130 Pa s), and the cross-sectional shape was a laminated type in which the component A was not covered with the component B. Other than that, the same procedure as in Example 1 was carried out.

[0122] As in Comparative Example 3, by using polytrimethylene terephthalate instead of polyethylene terephthalate as the A component polymer, the elastic modulus was lowered and the rigidity was lowered, so that the flexibility of the woven fabric was improved, but the resilience aimed at by the present invention was reduced. The results are shown in Table 1.

[0123] Comparative Example 5 In Comparative Example 5, a fabric was obtained in the same manner as in Example 1 using a 56 dtex-72 filament false twist yarn ("Tetoron W20L" manufactured by Toray Industries, Inc.) made solely of polyethylene terephthalate (PET3, melt viscosity 140 Pa·s).

[0124] The surface of the obtained woven fabric was clearly different from that of Example 1, with a surface roughness of 52 μm and a surface roughness CV% of 30%. The woven fabric of Comparative Example 5 was made of false twisted yarn, and the woven fabric surface was formed by mechanically applied crimp, resulting in a lowered smoothness compared to the woven fabric of Example 1. In addition, the fabric elongation was low, at most 8%, and did not have sufficient stretch performance. The results are shown in Table 1. [Explanation of symbols]

[0125] a: Center of gravity of component A in the cross section of the composite fiber b: Center of gravity of composite fiber cross section S: Minimum thickness of B component D: Fiber diameter IFR: Interface curvature radius 1: Weighing plate 2-1: Measuring hole for A component 2-2: Measuring hole for B component 3:Distribution plate 4: Discharge plate 5: Distribution groove 6: Distribution hole 7:Discharge introduction hole 8:Reduction hole 9:Discharge hole 10: Distribution hole for core A component 11: Distribution hole for sheath B component [Industrial Applicability]

[0126] This material exhibits fine and uniform crimping, making it possible to provide a stretch fabric suitable for comfortable clothing textiles, with a stretch performance that provides a moderate feeling of tightness, a bouncy feeling, and a pleasant, smooth feel.

[0127] Taking advantage of this smooth, pleasant texture, the fabric can be used for everything from outerwear and mid-layers to pants, and combined with its excellent stretchability, it can be used as a comfortable clothing textile for a wide range of applications, from sportswear to casual wear.

Claims

1. An eccentric core-sheath fiber consisting of two types of polymers, component A and component B, whose melt viscosity difference is 10 Pa·s or more, in which component A is completely covered by component B, In the cross section, the perimeter of a portion of the cross section of the fiber that is 1.05 times the minimum thickness of the B component covering the A component is 1 / 3 or more of the perimeter of the entire fiber, The single fiber fineness is 3.0 dtex or less, The elastic modulus is 70 cN / dtex or more, All warp and weft yarns are made of crimped fibers having a twist of 500 T / m or more, Fabric surface roughness (Ra) is 40 μm or less, The surface roughness CV% is 20 or less, the ratio of hysteresis (2HB) to stiffness (B), 2HB / B, is 2.0 cm -1 or less; A woven fabric characterized by having a fabric elongation rate of 20% or more.

2. 2. The woven fabric according to claim 1, wherein both of the components A and B constituting the crimped fibers are mainly composed of polyethylene terephthalate.

3. A woven fabric as described in claim 1 or 2, characterized in that the fabric stretch recovery rate is 80% or more.

4. A textile product in which the woven fabric according to any one of claims 1 to 3 is used at least in part.

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