JP2016098439A - Composite yarn and fabric using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a yarn and a fabric, having thermal insulating properties, a swelling feel and lightness in combination.SOLUTION: A composite yarn includes a hollow yarn having an approximately C-shaped cross-section and an elastic fiber. The hollow yarn has a wall thickness of 0.2 μm to 15.0 μm, and a loop height of 300 μm to 5000 μm.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a composite yarn composed of a yarn having a substantially C-shaped cross-sectional shape (hereinafter referred to as “substantially C-shaped cross-sectional yarn”) and an elastic fiber, and a fabric using the same.

  In recent years, from the viewpoint of ease of movement when worn, development of clothing that pursues lightness while maintaining necessary characteristics such as heat retaining properties and a feeling of swelling has been active. Various functional fibers have been developed for this purpose.

  Among these, a fiber having a hollow cross section (hereinafter referred to as a hollow fiber) is attracting attention. Hollow fibers have a large volume per fiber mass, are lightweight, have excellent heat retention, and have a moderate swell, and have long been used for short fibers such as stuffed cotton and futon cotton. In recent years, various types of long fibers that can be used for clothing and the like have been developed.

  As a method for producing a hollow fiber, a method for producing a hollow fiber by spinning and drawing using a spinneret for hollow is known (Patent Document 1, hereinafter, this method is referred to as “direct hollow forming method”). However, in the direct hollow forming method, it is difficult to obtain a hollow fiber having a high hollow ratio (for example, a hollow ratio of about 55% or more), and a single fiber fineness cannot be made. Further, the hollow fiber has high bending rigidity and a hard texture. Moreover, since a feeling of swelling and lightness may be impaired when twisting is performed, it is not possible to obtain a twisted hollow fiber. In order to increase the hollow ratio, an elution method has been developed in which a hollow fiber is produced by removing the core component from a core-sheath fiber having a core component and a sheath component.

  However, no matter which method is used, when hollow fibers are used as long fibers, the hollow portions are crushed by physical pressure during false twisting, twisting and weaving, and the target hollow ratio can be obtained. In addition, the original function of the hollow fiber is not sufficiently exhibited.

  In order to avoid such a problem, several ideas have been made. First, there is a method of changing the fiber cross-sectional shape to a C-shape. As an example, the sheath component of the core-sheath fiber is polyester, a part of the core component is exposed on the fiber surface, and an elution type hollow fiber-like fiber obtained by dissolving the core component (for example, a C-shaped cross section) Fiber) is known (Patent Document 2). The polyester fiber having a C-shaped cross section is not completely hollow in cross section, but is C-shaped, so that the hollow portion is relatively hard to be crushed, each single fiber has appropriate flexibility, and the softness is more emphasized. (Patent Document 3).

  Furthermore, if the elution of the hollow portion is performed after various processing, the hollow portion is not easily crushed. Polyester core-sheath composite fibers are known to be able to withstand physical pressure during false twisting and twisting and weaving and maintain the hollow part by removing the core component by reducing the amount of solvent such as alkali after weaving and weaving. (Patent Document 4).

JP 2007-270358 A JP 55-93812 JP-A 64-52839 JP2007-131980A

  However, although the fiber which gave the above-mentioned device can obtain the required lightness, there are the following problems.

  (1) The strength of the hollow fiber and the fabric obtained from the hollow fiber tends to be low as a whole, which is a problem in clothing that requires high strength. In particular, hollow fibers having a high hollow ratio have limitations when applied to various products.

  (2) The hollow fiber may have insufficient elongation especially in applications where stretchability is required (for example, sports clothing), and the resulting fabric has poor followability to the body when worn and is comfortable to wear Absent.

  (3) The feeling of swelling of the fiber itself is improved by making the cross section a C-shaped cross section, but it is not yet sufficient.

  Moreover, when creating a hollow part by the elution method, although the hollow rate higher than a direct hollow formation method is obtained, there exist the following subjects.

  (4) When removing the core portion of the hollow fiber after weaving and weaving, (i) combining with fibers that are vulnerable to alkali such as wool, silk, acrylic, rayon, cupra, and cationic polyester, and fibers that are easily discolored or deteriorated by alkali. (Ii) Fabrics combined with fibers with poor setting properties such as silk and rayon are prone to wrinkles due to the elution process after weaving and weaving. (Iii) Thick fabrics such as coated fabrics and pants fabrics A fabric with a large basis weight is physically impossible to perform elution after weaving and weaving with a conventional apparatus, and a dedicated elution apparatus is required.

  In order to solve the above-described problems, the present invention provides a composite yarn composed of a substantially C-shaped cross-sectional yarn and elastic fibers. This substantially C-shaped cross-sectional yarn has an average wall thickness of 0.2 μm to 15.0 μm and a hollow fiber loop height of 300 μm to 5000 μm.

  Other yarns may be included in the composite yarn as long as the properties such as lightness and swelling of the composite yarn are not impaired. Examples of other yarns include ordinary solid polyester yarns and solid polyamide yarns, but are not particularly limited. The other yarn is preferably contained in the composite yarn in an amount of 50% by mass or less.

  In a preferred embodiment of the present invention, the hollowness of the substantially C-shaped cross-sectional yarn is 55 to 80%, and the single yarn fineness is 0.1 to 50 dtex. In a further preferred embodiment of the present invention, the substantially C-shaped cross-sectional yarn is a false twisted yarn. In a preferred embodiment of the invention, the elastic fibers are polyurethane-based.

  Preferably, in the substantially C-shaped cross-sectional yarn, a hollow portion is formed by eluting a core portion of a composite yarn having a core component and a sheath component. More preferably, the elution is an elution using an alkaline solution. Preferably, in the composite yarn of the present invention, the elastic fiber is contained in an amount of 1 to 70% by mass in the composite yarn. By elution with alkali in the state of composite yarn instead of after forming the fabric, it can be combined with (i) fibers that are vulnerable to alkali such as wool or fibers that are easily discolored or deteriorated by alkali, and (ii) silk Cloths combined with fibers with poor setability, such as rayon, also eliminate wrinkling because an elution process after weaving is not necessary, and (iii) Fabrics with a large area weight such as coats and pants Even so, since it is knitted and woven after elution in the state of the composite yarn, it is possible to obtain a very light fabric using a conventional apparatus.

  Furthermore, the present invention also provides a fabric made using the composite yarn as described above. Preferably, the obtained fabric is a woven fabric, and the stretch rate of the woven fabric is 5% or more and the stretch recovery rate is 80% or more. In a preferred embodiment of the present invention, the obtained fabric is a knitted fabric, and the stretch rate of the knitted fabric is 90% or more and the stretch recovery rate is 80% or more. Furthermore, in a preferred embodiment of the present invention, the total fiber degree after elution of the composite yarn is 10 dtex or more and 500 dtex or less. More preferably, the fabric of the present invention has been brushed.

  In the present invention, by combining the elastic fiber with the substantially C-shaped cross-sectional yarn, the low strength of the substantially C-shaped cross-sectional yarn is supplemented by the elastic fiber in the core portion, so that the composite yarn as a whole has high strength. Therefore, the composite yarn of the present invention can be used for various products while maintaining the excellent properties such as lightness, softness and texture of the substantially C-shaped cross-sectional yarn. In addition, since the elastic fiber used for the core portion has a very high stretchability, the composite yarn of the present invention has a high stretchability, and the resulting fabric has good followability to the body when worn and is comfortable to wear. Is good. In addition, the composite yarn of the present invention has a substantially C-shaped cross-sectional yarn bulging in the cross-sectional direction of the substantially C-shaped cross-sectional yarn itself. Is a structure that is maximized. When a yarn having a large bulge is used, a fabric having a large bulge that is not conventionally obtained can be obtained.

FIG. 1 is a photomicrograph showing the cross section of a substantially C-shaped cross-sectional yarn according to an embodiment of the present invention (magnification 2000 times). FIG. 2 is an image of a composite yarn obtained by the “elution method after pre-mixing” shown below (400 × magnification). FIG. 3 is an image of a composite yarn obtained by the following “mixing method after elution” (400 × magnification). FIG. 4 is an image after removing the core component without mixing with the elastic fiber in the substantially C-shaped cross-sectional yarn according to one embodiment of the present invention (magnification 400 times). FIG. 5 is an image of a conventional cotton core spun yarn (comparative example) (400 × magnification).

Hereinafter, embodiments of the present invention will be described in detail.
The composite yarn of the present invention is composed of a substantially C-shaped cross-sectional yarn and elastic fibers.

(1. C-shaped cross section yarn)
The composite yarn of the present invention includes a substantially C-shaped cross-sectional yarn.

  In the present invention, the “substantially C-shaped cross-sectional yarn” means that a part of the hollow fiber wall is opened continuously in the fiber axis direction, and the cross-sectional shape is approximately C-shaped (deformed to be approximately V-shaped, approximately U-shaped). Threads (including those that look like molds).

  In this specification, the “eluting hollow fiber” is a yarn that has a core-sheath structure composed of a core component and a sheath component, and can form a yarn having a substantially C-shaped cross-sectional shape by removing the core component. In the fiber cross section, a part of the core component is exposed to the fiber surface from the opening of the sheath component.

  FIG. 1 is a photomicrograph showing a cross section of a substantially C-shaped cross-sectional yarn according to an embodiment of the present invention.

  A method for eluting the core component of the core-sheath yarn having a core component and a sheath component can be mentioned as a method for producing the substantially C-shaped cross-section yarn of the present invention. The core component can be removed by a general method of eluting the core component by utilizing the difference in solubility in a specific solvent between the core component and the sheath component of the core-sheath yarn. For example, using an alkaline solution Is eluted. The alkaline solution used for elution is preferably an aqueous solution such as sodium hydroxide or potassium hydroxide.

  The core component of the core-sheath yarn only needs to be easier to dissolve in the alkaline solution than the sheath component. For example, polyester using 5-sulfoisophthalic acid metal salt or / and polyethylene glycol as a copolymerization component is preferably used as the core component. Preferably, polyester using both 5-sulfoisophthalic acid metal salt and polyethylene glycol as a copolymerization component is used as the core component. Preferably, the 5-sulfoisophthalic acid metal salt is a sodium salt. The polyester is preferably polyethylene terephthalate. Preferably, the amount of 5-sulfoisophthalic acid sodium salt and polyethylene glycol to be copolymerized is 10% by mass to 30% by mass, more preferably 12% by mass to 20%, based on the total mass of the core component. % By mass. If it is less than 10% by mass, elution with an alkaline solution may be insufficient. On the other hand, when the amount is more than 30% by mass, the yarn-making stability may deteriorate.

  In addition, the core component polyester includes adipic acid, isophthalic acid, sebacic acid, phthalic acid, naphthalenedicarboxylic acid, 4,4′-diphenyldicarboxylic acid, cyclohexane as long as it does not interfere with the dissolution property with an alkaline solution and the stability of yarn production. Dicarboxylic acids such as dicarboxylic acids and ester-forming derivatives thereof, dioxy compounds such as diethylene glycol, hexamethylene glycol, neopentyl glycol, cyclohexanedimethanol, and oxycarboxylic acids such as p- (β-oxyethoxy) benzoic acid and ester formation thereof May be copolymerized.

  On the other hand, the sheath component of the core-sheath yarn only needs to be less soluble in the alkaline solution than the core component. Preferably, the sheath component contains polyester or polyamide as a main component.

  The polyester or polyamide used for the sheath component can be selected based on various factors such as solubility in an alkaline solution, texture, and dyeability depending on the application.

  Specific examples of the polyester selected as the sheath component include aromatic polyesters such as polyethylene terephthalate, polybutylene terephthalate and polytrimethylene terephthalate, and aliphatic polyesters such as polylactic acid. Preferably, polyethylene terephthalate is used.

  In the present invention, the above-described 5-sulfoisophthalic acid metal salt, polyethylene glycol, or the above-described oxycarboxylic acid, etc. are copolymerized with the polyester of the sheath component as long as the elution with an alkaline solution is lower than the core component. It may be.

  Also, the polyester of the sheath component is adipic acid, isophthalic acid, sebacic acid, phthalic acid, naphthalenedicarboxylic acid, 4,4′-diphenyldicarboxylic acid, cyclohexane as long as the elution property with an alkaline solution is lower than that of the core component. Dicarboxylic acids such as dicarboxylic acids and ester-forming derivatives thereof, dioxy compounds such as diethylene glycol, hexamethylene glycol, neopentyl glycol, cyclohexanedimethanol, and oxycarboxylic acids such as p- (β-oxyethoxy) benzoic acid and ester formation thereof May be copolymerized.

  Specific examples of the polyamide that can be used as the sheath component include, for example, nylon 6, nylon 66, nylon 610, nylon 56, nylon 11, or aromatic polyamide, and copolymerized polyamides thereof. A modified polyamide that mixes a vinyl component to develop hygroscopicity and contact cooling is also preferably used. When using polyamide for the sheath component, in addition to the core component as described above, polyester having higher solubility in an alkaline solution than polyamide may be used as the core component.

  The substantially C-shaped cross-section yarn of the present invention has an average wall thickness of 0.2 μm to 15.0 μm, preferably 0.3 μm to 10.0 μm, and more preferably 0.35 μm to 5.0 μm. For example, if the single fiber fineness of the hollow fiber before elution is 0.23 dtex and the hollow ratio is 80%, the thickness of the hollow fiber wall obtained after elution is about 0.26 μm. For example, if the single fiber fineness of the hollow fiber before elution is 110.0 decitex and the hollow ratio is 55%, the thickness of the hollow fiber wall obtained after elution is about 13.7 μm. A specific method for calculating the average wall thickness is described in “1-1. Evaluation Method for Approximate C-Shaped Section Thread (1)” in Examples. If the average wall thickness is less than 0.2μm, the strength is insufficient, and it is generally difficult to make by the direct hollow forming method. Insufficient control or difficulty in controlling elution loss occurs. The substantially C-shaped cross-section yarn of the present invention has a higher hollowness, which will be described later, than the conventional one, so that an average wall thickness is considerably small. On the contrary, when the average wall thickness exceeds 15.0 μm, the feeling of lightness is poor and the texture becomes hard.

  Further, the substantially C-shaped cross-section yarn of the present invention has a hollowness of 55% to 80%, preferably 60 to 70%. Here, the hollowness ratio is described in “1-1. Evaluation method of substantially C-shaped cross-sectional yarn (2)” in Examples.

  The hollowness is set from the viewpoints of high bulkiness, lightness, and heat retention, and in consideration of the mechanical strength of the knitted fabric after removing the core component, etc., and the hollowness of the substantially C-shaped cross-section yarn is 55%. The above is preferable. Compared with the conventional hollow fiber, the hollow ratio is large, the volume occupied by the fiber mass is large, and it has excellent bulkiness and lightness. When the hollow ratio exceeds 80%, the strength of the hollow fiber tends to decrease.

  The single yarn fineness of the substantially C-shaped cross-sectional yarn of the present invention is preferably 0.1 to 50 dtex. If it is less than 0.1 dtex, spinning may be difficult. When it exceeds 50 dtex, the texture tends to be hard.

  The elution type hollow fiber having the core-sheath structure of the present invention is preferably false twisted. By performing false twisting, the feeling of swelling and the bulkiness of the finally produced fabric increase. Depending on the false twisting temperature, the properties of the obtained yarn differ, and yarns suitable for various applications can be obtained. For example, a yarn that has been false twisted at a common false twisting temperature (for example, 180 ° C. to 220 ° C. for polyester and 160 ° C. to 190 ° C. for polyamide) has large crimps and high bulk, so that a thick fabric with a sense of volume. Is easy to obtain. Also, if the polyester filament yarn and the polyamide filament yarn are false twisted at a lower temperature (for example, 150 to 160 ° C. for the polyester filament yarn and 130 to 140 ° C. for the polyamide filament yarn), the crimp is reduced but the smoothness is reduced. In addition, since a silky touch can be obtained, it is particularly preferable as a medium thick yarn. Moreover, in order to manufacture a general-purpose yarn having both high bulkiness and smoothness, in the case of a polyester filament yarn, after false twisting at 180 ° C. to 220 ° C., the yarn may be set at 160 ° C. to 200 ° C. For polyamide filament yarns, false twisting at 160 ° C. to 190 ° C. and then setting at 160 ° C. to 180 ° C. is preferable.

(2. Elastic fiber)
The elastic fiber used for the composite yarn of the present invention is not particularly limited as long as it has elasticity. Specifically, the polyurethane elastic fiber, the polyether ester elastic fiber, and the polyester bimetal composite fiber (polyethylene terephthalate). / Polyethylene terephthalate, polyethylene terephthalate / polybutylene terephthalate, polyethylene terephthalate / polytrimethyl terephthalate, etc.) and highly crimped false twisted yarn. Preferably, the elastic fiber of the present invention is a polyurethane-based elastic fiber.

  By using a composite yarn mixed with elastic fibers, a fabric having excellent stretch properties and stretch recovery properties in addition to smoothness can be obtained, and favorable characteristics such as ease of wearing and a feeling of fit when worn can be obtained.

(3. Composite yarn)
The composite yarn of the present invention is composed of the aforementioned substantially C-shaped cross-sectional yarn and elastic fibers. The substantially C-shaped cross-section yarn and the elastic fiber are mixed and used by blending, twisting, or covering, and from the uniformity of stretch properties, twisting, air blending, covering, etc. are applied. Is preferred. In such processing, if the elastic fiber is processed into a polyester filament or polyamide filament yarn while being stretched by 2.0 to 4.0 times, the elastic fiber is arranged at the core of the processed yarn, and stretchability and stretch recovery properties are achieved. Is particularly preferable because it can be efficiently exhibited.

The composite yarn of the present invention has a loop height of 300 to 5000 μm, preferably 500 to 4500 μm, and has a very large loop height. In the present invention, the loop height of the substantially C-shaped cross-section yarn in the composite yarn is 1000 μm to 5000 μm in the case of air blending processing, 300 μm to 3000 μm in the case of manufacturing by twisting processing, and in the case of covering processing In the case of manufacturing a hollow fiber having a large loop height of 700 μm to 2000 μm, air mixed fiber processing is preferable.
The loop height can be controlled by combining the hollow fiber and the elastic fiber and then applying various treatments (for example, temperature, strain rate, etc.). Larger and smaller ones can be made by post-processing. The larger the loop height, the more air is contained between the elastic fiber and the substantially C-shaped cross section yarn, and the swelling of the composite yarn as a whole increases.

  The elastic fiber of the present invention is preferably contained in an amount of 1% by mass to 70% by mass on the basis of the total mass of the substantially C-shaped cross-sectional yarn and the elastic fiber from the viewpoint of stretchability and stretch recovery of the fabric. Furthermore, it is preferable that 2 mass%-50 mass%, and also 5 mass%-30 mass% are contained. If the amount is less than 1% by mass, the stretchability and the stretch recovery property are reduced, and if it exceeds 70% by mass, the feeling of tightening the fabric may be too strong.

  The composite yarn of the present invention preferably has a total fineness of 10 dtex or more and 500 dtex or less. Those having a total fineness of less than 10 dtex may be difficult to produce, while those having a total fineness exceeding 500 dtex tend to be too thick for clothing applications. Depending on the application, there is an optimum total fineness. For example, a fabric such as an ultra-thin garment is about 10 to about 50 dtex, a general thin fabric for women, a thin fabric for sports is about 50 to about 120 dtex, a medium-thick fabric, jacket, pants Is about 120 to about 200 decitex, and thick cloth, outer garment, coat, heavy garment (for example, judo clothes, kendo clothes, etc.) is optimally about 200 to about 500 dtex.

(4. Method of eluting the core component of the core-sheath thread)
The core component of the core-sheath yarn of the present invention can be removed by a general method for eluting the core component of the core-sheath yarn, and is eluted using, for example, an alkaline solution. The alkaline solution used for elution is preferably an aqueous solution such as sodium hydroxide or potassium hydroxide. The core component is removed by utilizing the property that the core component is more easily dissolved in, for example, an alkaline solution than the sheath component. As a method of eluting the core component in the yarn state, there is a method of eluting with an alkaline solution using a yarn dyeing equipment which is a conventional technique. Specifically, elution is performed using a cheese dyeing machine processed in the shape of cheese, or a case dyeing machine, a muff dyeing machine, or a star dyeing machine processed in the shape of a cake. It is particularly preferable to use a cheese dyeing machine from the uniformity of elution and the unwinding property of the yarn.

  In the core-sheath yarn of the present invention, the sheath component does not have a complete hollow structure, but has a C shape or the like, and a part of the core component is exposed to the fiber surface from the opening of the sheath component in the fiber cross section. Therefore, as compared with a yarn having a complete hollow structure, the alkaline solution easily penetrates into the core component, easily elutes under relatively mild conditions, and remains undissolved in the core component. The elution conditions vary depending on the composition of the core component, the apparatus used for the treatment, and the like, but the preferred concentration of the alkaline solution to be used is, for example, 0.5 to 40%. A preferable processing temperature is, for example, 80 ° C to 120 ° C. It is preferable to remove the core component within this range because it can be eluted uniformly and efficiently.

  As a method for eluting the core component of the elution type hollow fiber of the present invention, there are typically the following three methods.

  1. After producing a composite yarn by blending or twisting or covering the core-sheath yarn and the elastic fiber, the core component of the core-sheath yarn is eluted in the state of the yarn (hereinafter referred to as “the pre-mixing elution method”). ).

  2. After the core component of the core-sheath yarn is eluted, it is mixed with the elastic fiber or mixed or twisted or covered to produce a composite yarn (hereinafter referred to as “mixed after elution”).

  3. After producing a composite yarn by blending or twisting or covering the core-sheath yarn and the elastic fiber, weaving and weaving it into a fabric, and then eluting the core component (hereinafter referred to as “the post-weaving elution method”) Called).

  Depending on which of the three types of elution methods is used, the properties of the composite yarn and fabric to be obtained differ, which will be described later.

(5. Properties of composite yarn and fabric obtained by the above elution method)
The inventors of the present application have found that composite yarns and fabrics having various properties suitable for various applications can be obtained by changing the removal method of the core component even if the core-sheath fiber has the same composition. . Details are shown below. In this specification, “fabric” refers to a fabric such as a woven fabric, a knitted fabric, or a non-woven fabric. Examples of the woven fabric include plain woven fabric, twill woven fabric (also referred to as oblique woven fabric), satin woven fabric, and double woven fabric. Examples of the knitted fabric include a knitted fabric such as a circular knitting, a warp knitting, and a flat knitting.

(5-1. Properties of composite yarn and fabric obtained by elution method after pre-mixing)
FIG. 2 is a photomicrograph of a composite yarn obtained by the elution method after premixing (magnification 400 times). The details of the method for producing the composite yarn of FIG. 2 and the elution method after pre-mixing are shown in Example 1 below. In FIG. 2, an elastic fiber is present at the center, and an elution-type hollow fiber having a substantially C-shaped cross-sectional shape of the present invention is entangled around the elastic fiber to form a large loop shape. Since the core component of the substantially C-shaped cross-sectional yarn is removed after mixing the substantially C-shaped cross-sectional yarn and the elastic fiber, the substantially C-shaped cross-sectional yarn is held by the elastic fiber so that the core component is not stretched. It is considered that the shape of the hollow portion is easily maintained later. Actually, according to FIG. 2, the crimps of the substantially C-shaped cross-section yarn remain cleanly, and a large amount of air is contained between the substantially C-shaped cross-sectional yarns and between the elastic fiber and the substantially C-shaped cross-sectional yarn. Further, since there are fine crimps, it is considered that the loop of the substantially C-shaped cross-section yarn is not easily crushed.

  The fabric made from the composite yarn obtained by the elution method after the pre-mixing is considered to be very light and has excellent heat retention and large swelling due to the characteristics of the composite yarn described above. Excellent properties for clothing.

(5-2. Properties of composite yarn and fabric obtained by the mixed method after elution)
FIG. 3 is a photomicrograph of the composite yarn obtained by the pre-elution mixed method (400 times magnification). The details of the method for producing the composite yarn of FIG. 3 and the elution method after premixing are shown in Example 2 below. The composite yarns of FIGS. 2 and 3 have the same composite yarn composition and differ only in the elution method. As is apparent from a comparison of FIG. 2 and FIG. 3, by changing the elution method, a composite yarn having a significantly different appearance can be obtained from the same composition. In the pre-elution mixed method, the core component of the substantially C-shaped cross-sectional yarn is eluted and then mixed with the elastic fiber. Similar to the composite yarn of FIG. 2, an elastic fiber is present at the center, and an elution-type hollow fiber having a substantially C-shaped cross section of the present invention is entangled around the elastic fiber to form a large loop shape. However, the substantially C-shaped cross-section yarn has a relatively smooth appearance, and the crimp is not so large.

  Therefore, the fabric made from the composite yarn obtained by the pre-elution mixed method is considered to be smoother and more breathable than the fabric made from the composite yarn of FIG. It has excellent characteristics as a spring and summer garment.

  In addition, since both the composite yarn of FIG. 2 and the composite yarn of FIG. 3 use a substantially C-shaped cross-sectional yarn, they are higher in weight than the case of using solid fibers, and the resulting fabric is very light. Soft and fluffy, with high stretch rate and high stretch recovery. In addition, since a substantially C-shaped cross-section yarn is used instead of a hollow fiber, it retains excellent properties such as lightness, softness, and texture that are characteristic of a substantially C-shaped cross-section yarn.

(5-3. Properties of fabric obtained by elution method after weaving)
Compared with the case where the core component of the substantially C-shaped cross-sectional yarn is removed in the state of the yarn, in the fabric obtained by the post-woven weaving method, the loop of the substantially C-shaped cross-sectional yarn is relatively small and uniform. Therefore, the obtained fabric has very uniform heat retention, high bulkiness, stretchability, and high dimensional stability.
(6. Fabric)
The fabric using the composite yarn of the present invention is preferably used as a woven fabric or a knitted fabric.
The woven fabric preferably has an elongation rate of 5% or more and an elongation recovery rate of 80% or more. An elongation rate of 5% or more is preferable because it can follow the movement of the body. It is particularly preferable that the elongation rate is 5% to 40% from the viewpoint of ease of movement and fit when worn. The elongation recovery rate of the fabric of the present invention is preferably in the range of 80 to 95%. In this range, the fit and wear comfort are excellent. Moreover, there is little loss of shape and excellent shape retention. If it is less than 80%, recovery may be inferior. Moreover, the thing over 95% cannot generally be manufactured.

  The knitted fabric preferably has an elongation rate of 90% or more and an elongation recovery rate of 80% or more. The stretch rate is particularly preferably 100% to 200% from the viewpoint of ease of movement and fit when worn. The elongation recovery rate of the knitted fabric of the present invention is preferably in the range of 80 to 95% for the same reason as in the case of the woven fabric.

(7. Brushed treatment)
You may raise the fabric of this invention. The raising process can be performed using a general raising machine such as a needle cloth raising machine or a buff raising machine. Generally, when a needle cloth raising machine is used, fine, dense and long fluff is obtained, and when a buff raising machine is used, a short and coarse fluff is obtained. It is not bound by theory, but by raising, the sheath portion of the approximately C-shaped cross-section yarn is finely cut, split, and cracked, so there are fluffs with fine features that have not existed in the past Can be obtained. When raising the back surface (the side that touches the human body) of the fabric, friction with the skin is reduced, a smooth texture is obtained, and it feels warm when worn. When the surface (outside air side) of the fabric is raised, the gloss, appearance, and touch are improved.

  Hereinafter, the present invention will be described in detail based on examples, but the present invention is not necessarily limited thereto.

(Evaluation method)
(1. Analysis of substantially C-shaped cross-sectional yarn, composite yarn, and fabric)
The substantially C-shaped cross section yarn, composite yarn and fabric produced by the method of the present invention were analyzed by the following method.

(1-1. Evaluation method of substantially C-shaped cross-section yarn)
(1) Thickness (μm)
A single yarn having a substantially C-shaped cross section was cut, and a cross section of the yarn was photographed at a magnification of 2000 using a scanning microscope. Using the obtained micrograph, the wall thickness (unit: μm) of the substantially C-shaped cross-sectional yarn was measured. An arbitrary 10 points of the C-shaped cross section were selected and measured for one yarn (n = 10). This measurement was performed on ten yarns, and the average value of the measured values was taken as the thickness (μm) of the hollow fiber. The smaller the thickness, the lighter and softer the yarn.

(2) Hollow ratio (%)
The photomicrograph obtained in (1) above was enlarged and copied to paper. Next, the C-shaped cross section including the hollow portion was cut off at the contour portion, and the mass (S ₀ ; unit g) was measured. Further, the hollow portion is cut off at the contour portion, and the mass (S ₁ ; unit g) of the hollow portion is measured. S ₀ and S ₁ were measured for 10 C-shaped sections. The hollow ratio was determined by the following formula.

Hollow ratio (%) = S ₁ (g) / S ₀ (g) × 100
(1-2. Evaluation method of composite yarn)
The composite yarn of the present invention was evaluated by the following method.

(1) Appearance Evaluation For each yarn, a digital microscope VHX-1000 (manufactured by Keyence Corporation) was used to take micrographs magnified at a magnification of 400 times to evaluate the appearance of the yarn.

Evaluation items: How to wrap the yarn, loop shape, presence or absence of crimp, etc. (2) Loop height Each yarn is used with precision universal testing machine Autograph AG-IS (manufactured by Shimadzu Corporation), (a) An image magnified at a magnification of 400 times was obtained using the digital microscope VHX-1000 (manufactured by Keyence Corporation) as it was without load, or pulled with (b) a load of 0.5 g and (c) a load of 6 g. The position of the elastic fiber in the center is set to 0, the largest part of each loop is measured perpendicularly from the elastic fiber, 20 points are measured for each of the loop heights Ha, Hb, Hc, and the loop height is obtained as an average value. Ha, Hb, and Hc (unit: μm) were obtained.

Loop height Ha = Loop height measured without load (μm)
Loop height Hb = Loop height measured at a load of 0.5 g (μm)
Loop height Hc = loop height measured at 6 g load (μm)
(3) Loop retention rate Hb / Ha and Hc / Ha were calculated from the loop height in (2) (unit%). As the values of Hb / Ha and Hc / Ha are larger, the loop is less likely to be crushed even when a load is applied.

(4) Elongation and strength of yarn: Tensile test Each yarn measured in accordance with 8.5.1 “Standard time test” (JIS method) of 8.5 “Tensile strength and elongation” of JIS L1013 of 2014 edition At an initial load of 0.5 g, a tensile tester is used to perform a tensile test. The relationship between the force (cN) applied to the yarn until it was cut and the stroke (strain) of the yarn was graphed to obtain the strength (cN) and elongation (%) at the time of yarn cutting (average of n = 10) value). Yarn strength was expressed as strength per decitex (cN / dtex).

(5) Yarn strength (toughness, high elongation product)
From (4) above, the product of strong elongation (% · cN / dtex) = elongation (%) × strength (cN / dtex) was determined. The larger the value of the product of strength and elongation, the stronger the yarn and the greater the toughness.

  In addition, when measuring the loop height, loop elongation rate, etc. of the constituent yarn after making it once into a fabric, the fabric is disassembled and the above evaluation is performed on the obtained yarn.

(1-3. Fabric Evaluation Method)
The created fabric was evaluated by the following method.

(1) Lightness of fabric: basis weight (g / m ² )
The lightness of the fabric was expressed by the basis weight (g / m ² ) of the fabric measured according to the A method (JIS method) described in 8.3.2 of JIS L1096 of the 2014 edition. The smaller the value, the lighter.

(2) Fabric thickness: Thickness (mm)
It was measured according to 8.4 A method (JIS method) of JIS L1096 of 2014 edition (constant time: 10 seconds, constant pressure: 23.5 kPa).

(3) Sense of swelling of fabric: high altitude (cm ³ / g)
The bulk height (cm ³ / g) was obtained by dividing the thickness (mm) by the basis weight (g / m ² ) and multiplying by 1000.

(4) Smoothness of fabric: surface roughness SMD value Evaluation apparatus: The surface roughness SMD value (μm) of the back surface of the fabric was measured using a KES-FB4 surface tester (manufactured by Kato Tech Co., Ltd.). In the case of a woven fabric, the warp direction (vertical) and the weft direction (horizontal) on the back side were measured at three locations, and the average value was obtained. In the case of a knitted fabric, the wale direction and the course direction of the knitted fabric were measured at five locations, and the average value was obtained. The smaller the value is, the better the fabric has less unevenness.

(5) Softness of fabric: Bending rigidity B value Evaluation device: Using KES-FB2 pure bending tester (manufactured by Kato Tech Co., Ltd.), in the case of a fabric, the fabric was bent in the warp direction and the weft direction. The average bending stiffness B value (gf · cm ² / cm) of the fabric was measured (N = 3 for each of the warp and the weft). In the case of the knitted fabric, the average bending stiffness B value (gf · cm ² / cm) when the knitted fabric was bent in the wale direction and the course direction was measured (N = 5 for each). The smaller the value, the lower the stiffness and the softer the texture.

(6) Elongation rate of the fabric The evaluation was performed according to the 2014 edition, JIS L1096, section 8.14.1, method A (strip method). In the case of a woven fabric, measurement was performed three times for each of the warp direction and the weft direction, and an average value was calculated. In the case of a knitted fabric, measurement was performed five times in the wale direction and the course direction, and an average value was calculated. The larger the value, the better the elongation.

(7) Elongation recovery rate of fabric For fabric:
The weft direction or the weft direction of the woven fabric was measured and evaluated in accordance with the 2014 edition of JIS L1096, Section 8.15.1, “Method A, b,“ Elongation elastic modulus at repeated constant rate elongation ”(repeated 5 times). The higher the value, the better the recoverability after stretching.

For knitting:
According to the 2014 edition of JIS L1096 section 8.16.2, D method “Repeated Constant Elongation Method”, 5 sheets were measured in the waling direction and the course direction of the knitted fabric, respectively, and a load-elongation curve was drawn. The higher the value, the better the recoverability after stretching.

(Example 1 Preparation of composite yarn-pre-mixed elution method)
(1) Preparation of an elution-type hollow fiber (non-eluting) As a core component, polyethylene terephthalate containing 4.8 mol% of 5-sulfoisophthalic acid sodium salt and 10.6% by mass of polyethylene glycol as a copolymer component, and as a sheath component Using polyethylene terephthalate, the core component / sheath component is discharged at a spinning temperature of 290 ° C. from a core-sheath cross-section C-type nozzle nozzle (36 holes) in which the sheath component side is C-shaped so that the mass ratio of the core component / sheath component is 60/40. Spinning was performed at a spinning speed of 3000 m / min, and a filament having a total fineness of 140 dtex and 36 filaments was once wound up as a partially oriented composite fiber yarn having a substantially C-shaped fiber cross-section. Subsequently, the obtained partially oriented composite fiber yarn was false twisted at a heat setting temperature of 165 ° C., a draw ratio of 1.7 times, and a processing speed of 600 m / min by using a drawing false twister, and the core / sheath An elution-type hollow fiber (non-eluting) having a mass ratio of 60/40, a total fineness of 84 dtex, and 36 filaments was obtained.

(2) Preparation of blended yarn of elution-type hollow fiber (non-eluting) and polyurethane elastic fiber Subsequently, the above-described elution-type hollow fiber (non-eluting) is aligned (total fineness 504 dtex), 44 dtex polyurethane elasticity The fiber “Lycra” (manufactured by Toyo Leoperontex Co., Ltd.) was entangled with air while being stretched 3.3 times and mixed. The obtained polyester / polyurethane elastic fiber mixed yarn had a total fineness of 548 dtex.

(3) Removal of core component of hollow fiber Thereafter, this composite yarn was once wound into a soft cheese shape. Then, put it into a cheese dyeing machine, which is a yarn dyeing facility, and treat the elution-type hollow fiber obtained as described above with a 2.5% aqueous sodium hydroxide solution at 100 ° C. for 40 minutes to completely remove the core component. Thus, a composite yarn of Example 1 including an elution-type hollow fiber having a hollow ratio of 60% (eluted) was obtained. The total fineness was 246 dtex, the single yarn fineness was 0.93 dtex, and the wall thickness of the hollow fiber was 1.73 μm. The resulting composite yarn was extremely light, soft and suitable for wide use in fabrics. The evaluation results are shown in Table 1 below.

(Example 2 Preparation of composite yarn-mixed method after first elution)
As described in (2) of Example 1, after the elution-type hollow fiber (non-eluting) core component prepared in (1) of Example 1 was eluted by the same method as (3) of Example 1. , 6 elution-type hollow fibers (after elution) are aligned, and 44 decitex polyurethane elastic fiber “Lycra” (manufactured by Toyo Perontex Co., Ltd.) is stretched 3.3 times while being entangled with air and mixed. A composite yarn of Example 2 was obtained. The obtained hollow fiber was extremely light, soft and suitable composite yarn widely used for fabrics. The evaluation results are shown in Table 1 below.

(Comparative Example 1 Preparation of hollow fiber)
The core component was eluted in the same manner as in (3) of Example 1 without mixing the elution-type hollow fiber (non-eluting) prepared in (1) of Example 1 with urethane elastic fiber, thereby obtaining Comparative Example 1. .

(Comparative Example 2 Cotton core spun yarn)
As a comparative example, a conventional cotton core spun yarn (polyurethane elastic yarn having a core of 44 dtex was covered with cotton 11.8 count).

(Evaluation of composite yarn)
Using the composite yarns obtained in Examples 1 and 2 and the yarns of Comparative Examples 1 and 2, the evaluation was performed based on the above-mentioned “1-2. Evaluation method for composite yarn”. The evaluation results are shown in Table 1.

* 1 Average value of n = 20 each
* 2 Not measured because it is not mixed with urethane elastic fiber. From the results in Table 1, the loop height of the composite yarns of Example 1 and Example 2 is much higher than that of the cotton core spun yarn of the comparative example. Big. Further, from the values (Hb, Hc) when the load is applied and the value of the loop retention rate, the loop is retained even when the load is applied up to 0.5 g (for example, with the load of 0.5 g, in Example 1) The loop retention rate was 76.3%, which was 87.5% in Example 2, compared with 55.8% in Comparative Example 2, and it was found that the loop was not easily crushed even when a load was applied. Further, the composite yarn of the present invention was very strong because the strength of the yarn was considerably larger than that of the comparative example.

(Example 3 Measurement of wall thickness of hollow fiber)
In accordance with the method described in Example 1, composite yarns were prepared using hollow fibers of various thicknesses, and the wall thickness after elution was measured. The results are shown in Table 2 below.

  Each characteristic yarn was obtained. For example, the yarn of Example 1 was a very light, suitable yarn that was soft and widely used in fabrics. In addition, the yarns of Examples 3-A and 3-B were extremely light as blades, and were suitable as thin fabrics. The yarn of Example 3-F was a yarn that was extremely light and soft compared to conventional monofilaments, and was rich in tension and waist.

(Example 4 creation of denim)
(1) Weaving Navy cotton indigo-dyed No. 9 single yarn was used as the warp, this was glued and warped, and the composite yarn obtained in Example 1 was driven into it as a weft to make a raw fabric. The structure of the woven fabric was a 3/1 twill structure. The width of the machine was 175 cm, the warp density was 68 / 2.54 cm, and the weft density was 45 / 2.54 cm.

(2) Finishing process Next, this woven fabric was continuously subjected to desizing and scouring processing in an expanded form, subjected to sanforization processing, and set at 180 ° C. Further, this woven fabric was washed with a washer at 40 ° C. for 10 minutes (one washer processing), and was finally finished.

(Example 5 creation of denim)
A denim fabric was prepared in the same procedure as in Example 4 except that the composite yarn obtained in Example 2 was used as the weft.

(Comparative example 3 creation of denim)
A denim fabric was prepared in the same procedure as in Example 4 except that the hollow fiber obtained in Comparative Example 1 was used as the weft. The stretch rate of the obtained denim fabric was 2%, the stretch recovery rate was 15%, and there was almost no followability to the body.

(Comparative example 4 creation of denim fabric)
A denim fabric was prepared in the same procedure as in Example 4 except that the cotton core spun yarn of Comparative Example 2 was used as the weft.

  The following table summarizes the characteristics of the denim fabric using the composite yarn of the present invention (Example 4) and the denim fabric using the cotton core spun yarn (Comparative Example 4) (the evaluation method is “1”). -2. "Method for evaluating fabric").

Product evaluation was performed on the final finished fabrics obtained in Example 4 and Comparative Example 4, and the results are shown in Table 3. The finished width was 130 cm, the warp density was 89 / 2.54 cm, the weft density was 51 / 2.54 cm, and the basis weight was 328 g / m ² . The total mixing ratio of the woven fabric was 81% by weight cotton, 17% by weight polyester, and 2% by weight polyurethane elastic fiber.

  As described above, when the composite yarn of the present invention is used, it is extremely light and swelled, which is not obtained by the prior art, and it is comfortable to wear with a soft and dry texture, and has excellent stretchability and stretch recovery. A denim fabric was obtained.

(Example 6 Preparation of pants fabric using elution method after weaving)
(1) Preparation of core-sheath thread (not eluted) As a core component, polyethylene terephthalate using 5.2 mol% of 5-sulfoisophthalic acid sodium salt and 10.4% by mass of polyethylene glycol as a copolymer component, and as a sheath component Using polyethylene terephthalate, the core component / sheath component is discharged at a spinning temperature of 290 ° C. from a core-sheath cross-section C-type nozzle nozzle (36 holes) in which the sheath component side is C-shaped so that the mass ratio of the core component / sheath component is 60/40. Spinning was performed at a spinning speed of 3000 m / min, and a filament having a total fineness of 140 dtex and 36 filaments was once wound up as a partially oriented composite fiber yarn having a substantially C-shaped fiber cross-section. Subsequently, the obtained partially oriented composite fiber yarn was false twisted at a heat setting temperature of 165 ° C., a draw ratio of 1.7 times, and a processing speed of 600 m / min by using a drawing false twister, and the core / sheath A core-sheath yarn (not eluted) having a mass ratio of 60/40, a total fineness of 84 dtex, and 36 filaments was obtained.

(2) Preparation of blended yarn of core-sheath yarn (non-eluting) and polyurethane elastic fiber Next, two core-sheath yarns (non-eluting) are aligned (total fineness 504 dtex), 22 dtex polyurethane elastic fiber “ While stretching “Lycra” (manufactured by Toyo Leoperontex Co., Ltd.) 3.3 times, it was entangled with air and mixed.

(3) Weaving The above-mentioned (1) 84 dtex, 36-filament core-sheath yarn (uneluting) is used for the warp, the above-mentioned (2) mixed fiber composite yarn is used for the weft, and the fabric is woven using an air loom. I made it. The structure of the woven fabric was a 2/1 twill structure, the raw machine width was 159 cm, the warp density was 178 / 2.54 cm, the weft density was 100 / 2.54 cm, and the basis weight was 148 g / m ² .

(4) Finishing process Next, the woven fabric was continuously subjected to desizing and scouring in an expanded form, and set at 180 ° C. Then, it processed for 35 minutes at 105 degreeC using 2.0% sodium hydroxide aqueous solution in a liquid dyeing machine, and removed the core component of the hollow fiber completely. The fabric was then dyed at 130 ° C. with 0.5% owf blue disperse dye. Then, it was set at 160 ° C. and finished.

The resulting woven fabric had a width of 153 cm, a warp density of 185 strands / 2.54 cm, a weft density of 105 strands / 2.54 cm, and the weight loss rate of the hollow fiber portion was 60.2%. The obtained fabric has a basis weight of 59.2 g / m ² , a thickness of 0.32 mm, a bulk height of 5.41 cm ³ / g, a stretch rate (width) of 38%, and an elongation recovery rate of 90.2%. Met. The texture was soft and extremely light, and it was a smooth, high-quality blue twill fabric.

(Comparative example 5 creation of pants)
Other than using normal polyethylene terephthalate filaments (84 dtex, 36 filaments) for warp and combining normal polyethylene terephthalate filaments (84 dtex, 36 filaments) and polyurethane elastic fibers (44 dtex) for wefts. A green fabric was produced in the same manner as in Example 6. After the raw fabric was prepared, it was dyed and finished according to Example 6 without being subjected to elution weight loss processing.

The resulting woven fabric had a width of 153 cm, a warp density of 185 / 2.54 cm, and a weft density of 105 / 2.54 cm. The obtained fabric has a basis weight of 153.9 g / m ² , a thickness of 0.29 mm, a bulk height of 1.88 cm ³ / g, a stretch rate (horizontal) of 26.2%, and an elongation recovery rate of 81. 3%. Although the stretch rate and elongation recovery rate were excellent, the texture was hard, and it was a mediocre woven fabric with no features in lightness, smoothness, and bulkiness.

(Example 7 Wool blended fabric)
According to Example 1, a composite yarn containing an elution type hollow fiber (eluted) having a hollow ratio of 60% was obtained. The fineness after elution was 202 dtex-216 filament + urethane 44 dtex. The hollow fiber elution weight loss rate was 60.3%.

  A 52-mm wool was used for the warp and the above-mentioned composite yarn was used for the weft to obtain a plain fabric fabric. Subsequently, this woven fabric was continuously subjected to desizing and scouring in an expanded form, and set at 180 ° C. The fabric was then dyed at 105 ° C. using a gray acid dye and a gray disperse dye. Then, semi-deca processing (processing to press the surface yarn with steam) was finished.

  The texture of the resulting fabric was soft, swelled, smooth and extremely light. In addition, the stretch (horizontal) rate was 28.3%, and the elongation recovery rate was 88.3%, and a gray plain woven fabric full of functionality and luxury was obtained.

(Comparative Example 6 Wool blended fabric)
Example 7 and Example 7 except that the core / sheath mass ratio of Example 1 is 60/40, the total fineness is 85 dtex, and the 36 filament core / sheath thread (not eluted) is used as the weft instead of the composite yarn of Example 7. The same procedure was performed to obtain a green fabric having a plain structure.

  Thereafter, an elution process was attempted using a liquid dyeing machine, but the wool side was broken by the alkaline solution and could not be processed.

Example 8 Preparation of knit fabric
One elution-type hollow fiber (not eluted) of Example 1 (1) (total fineness of 84 dtex, 36 filaments) and 22 dtex polyurethane elastic fiber “Lycra” (manufactured by Toyo Perontex Co., Ltd.) Twisting while stretching 3 times. Thereafter, the raw yarn was once rolled back into a soft cheese shape. Then, put it into a cheese dyeing machine, which is a yarn dyeing facility, and treat the elution-type hollow fiber obtained as described above with a 2.0% aqueous sodium hydroxide solution at 100 ° C for 45 minutes to completely remove the core component. Thus, a composite yarn containing a substantially C-shaped cross-sectional yarn (eluted) having a hollowness of 60% was obtained.

This composite yarn was used to knit with a hook diameter of 34 mm (2.54 cm) and a gauge number of 32 gauges to obtain a tengu structure. At the time of knitting, a knitted fabric was prepared by applying 2.2 g of knitting tension to the composite yarn. The resulting product had a width of 154 cm and a basis weight of 78 g / mm ² . This product was refined according to a conventional method, set at 180 ° C., then dyed at 130 ° C. with a blue disperse dye and finished. The finished knitted fabric had a width of 150 cm, a basis weight of 65 g / mm ² , and a thickness of 0.25 mm.

The obtained knitted fabric had a bulk height of 3.85 cm ³ / g, a stretch rate (horizontal direction) of 125.4%, and an elongation recovery rate (horizontal direction) of 89.3%. The obtained knitted fabric was light (weighing 65 g / mm ² ), soft in texture, and a smooth, smooth blue knitted knitted fabric.

(Comparative Example 7 Creation of knit fabric)
Instead of the composite yarn containing a substantially C-shaped cross-section yarn (eluted) of 60% in Example 8, a normal round-section polyethylene terephthalate filament yarn (84 dtex, 36 filament) was replaced with 22 dtex polyurethane elasticity. The fiber “Lycra” (manufactured by Tolo Perontex Co., Ltd.) was twisted while being stretched 3.3 times. Using this composite yarn, a blue knitted fabric was obtained in the same procedure as in Example 8. The resulting product had a width of 154 cm and a basis weight of 195 g / mm ² . This product was refined according to a conventional method, set at 180 ° C., then dyed at 130 ° C. with a blue disperse dye and finished. The finished knitted fabric had a width of 150 cm, a basis weight of 162 g / mm ² , and a thickness of 0.35 mm.

The obtained knitted fabric had a bulk height of 2.16 cm ³ / g, a stretch rate (horizontal direction) of 83.2%, and an elongation recovery rate (horizontal direction) of 62.3%. The obtained knitted fabric had no feeling of light weight, had a hard texture, and had a rough texture and an ordinary tengu knitted fabric.

Example 9 Denim fabric with brushed finish
The denim raw fabric obtained in Example 4 (1) was scoured, sanforized and set according to Example 4 (2). Next, the raw fabric was brushed. Using a needle cloth raising machine, the back side of the fabric was raised three times. After raising, the one washer was processed and finished according to Example 4 (2). The stretch rate (horizontal) was 31.4%, and the elongation recovery rate was 89.2%. The finished product was light and soft in color, and the fluff on the back was fine, dense and warm. Denim suitable for autumn / winter use was obtained.

Claims (12)

  A composite yarn composed of a substantially C-shaped cross-sectional yarn and an elastic fiber, wherein the average thickness of the wall of the C-shaped cross-sectional yarn is 0.2 μm to 15.0 μm, and the substantially C-shaped cross-sectional yarn is an elastic fiber. A composite yarn characterized by being mixed, twisted or covered at a loop height of 300 μm to 5000 μm.   The composite yarn according to claim 1, wherein the hollowness of the C-shaped cross-sectional yarn is 55 to 80%.   The composite yarn according to claim 1 or 2, wherein the single yarn fineness of the C-shaped cross-sectional yarn is 0.1 to 50 dtex.   The composite yarn according to any one of claims 1 to 3, wherein the C-shaped cross-sectional yarn is a false twisted yarn.   The composite yarn according to any one of claims 1 to 4, wherein the elastic fiber is polyurethane.   The composite yarn according to any one of claims 1 to 5, wherein the substantially C-shaped cross-sectional yarn elutes a core portion of the composite yarn having a core component and a sheath component to form a hollow portion.   The composite yarn according to any one of claims 1 to 6, wherein the elastic fiber is contained in the composite yarn in an amount of 1 to 70% by mass.   A fabric made using the composite yarn according to any one of claims 1 to 7.   The fabric according to claim 8, wherein the fabric is a woven fabric, and the stretch rate of the woven fabric is 5% or more and the stretch recovery rate is 80% or more.   The fabric according to claim 8, wherein the fabric is a knitted fabric, and the stretch rate of the knitted fabric is 90% or more and the stretch recovery rate is 80% or more.   The fabric according to any one of claims 8 to 10, wherein the total fineness of the composite yarn is 10 dtex or more and 500 dtex or less.   The fabric according to any one of claims 8 to 11, wherein the fabric is raised.