JPH1161581A - Core-sheath conjugate spun yarn and cloth - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain the subject spun yarn having excellent fashionability and bulkiness with loops and suitable as a material for interior use or clothes by constituting the core component with high-shrinkage polyester staple fibers or high-shrinkage polyacrylonitrile staple fibers and the sheath component with low-shrinkage staple fibers. SOLUTION: The staple fiber bundle A of a core component is composed of high-shrinkage polyester staple fibers or high-shrinkage polyacrylonitrile staple fibers having a hot-water shrinkage of 20-40% and the staple fiber bundle B of the sheath component is composed of low-shrinkage staple fibers (synthetic or natural fibers) having a hot-water shrinkage of 0-10%. The fiber bundle B is successively wound on the fiber bundle A with a ring spinning frame having a pair of front taper rollers to obtain the objective core-sheath conjugate spun yarn having high loop radius ratio and good appearance and form.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a core-sheath composite spun yarn and a fabric using the same. More specifically, a core-sheath composite spun yarn consisting of high-shrinkage polyester short fibers or high-shrinkage polyacrylic short fibers as a core component and low-shrinkage short fibers as a sheath component. And a core-sheath composite spun yarn suitable for a material for clothing and a fabric using the same.

[0002]

2. Description of the Related Art Conventionally, loop yarns have been used for a very wide range of uses such as clothing, industrial materials, and interiors because of their bulkiness and change in appearance of fabrics.

On the other hand, in recent years, the use for interior and interior of vehicles has been remarkably growing, and it has been desired to reduce the weight of a vehicle body and to improve fashionability in order to improve fuel efficiency. For this reason, there is a strong demand for a loop yarn having a larger change in the appearance of the fabric, and being bulky and excellent in weight reduction, and accordingly, a material for clothing is also bulkier than before, and a loop-like composite yarn excellent in fashionability and weight reduction is desired. It is rare.

On the other hand, a conventional loop-like composite yarn is
Filament yarns by a design twisting machine, filament yarns and spun yarns, or spun yarns utilizing the difference in shrinkage or cross-twisted yarns of filament yarns are generally widely used. Since the fibers are strongly twisted because they need to be fixed, the convergence of the short fibers of the loop component or the short fibers of the core yarn becomes strong, and when the fabric is used, bulkiness cannot be obtained, and a satisfactory weight reduction can be obtained. Not yet.

Furthermore, Japanese Patent Application Laid-Open No. 6-158465, in which a filament yarn and a spun yarn are mixed and entangled, Japanese Patent Application Laid-Open No. 58-8134, which is combined with an air spinning machine, and Japanese Patent Publication No. 41-6308, which is combined with a spinning machine. Gazette, JP-B-63-3156
No. 8, JP-A-60-110947, etc., but all of them are strongly twisted to prevent the loop from shifting due to insufficient bonding with the filament yarn, so that satisfactory bulk performance is not obtained. .

Also, Japanese Utility Model Laid-Open No. 5-51981, Japanese Patent Publication No. 61-38, using spun yarn instead of filament yarn.
No. 89, but the spun yarn is used as a filament yarn substitute, and it is twisted, so it is difficult to increase the loop shape, and the spun yarn is not tightened and satisfactory bulkiness cannot be obtained. When untwisted, the bulkiness is obtained, but the morphological stability of the loop is deteriorated, a lot of fly waste comes out in the complex processing process, operability is impaired, processing becomes difficult, and satisfactory productivity is obtained. Not.

In the case where a low-shrinkage spun yarn is used as a sheath in the untwisting direction instead of a filament yarn and a composite is spun using a high-shrinkage staple fiber as a core, the high-strength spinning tension of only the high-shrinkage staple fiber at the core is used. Therefore, the twist coefficient must be set high, and the obtained composite yarn is tight, and it is difficult to obtain a satisfactory bulkiness and a large loop shape.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to solve the above-mentioned drawbacks, and it is a core-sheath type composite spun yarn having a core component of a high shrinkage short fiber and a sheath component of a low content. An object of the present invention is to provide a core-sheath composite spun yarn and fabric which are composed of shrinkable staple fibers, have a loop-like shape, and are excellent in fashionability and bulkiness.

[0009]

The core-sheath composite spun yarn of the present invention that achieves the above object has the following constitution. That is, (1) a core-sheath type composite spun yarn, and a short fiber bundle A of a core component
Is composed of high shrinkage polyester short fibers or high shrinkage polyacrylic short fibers having a hot water shrinkage of 20% to 40%, and the short fiber bundle B of the sheath component is formed of low shrinkage short fibers having a hot water shrinkage of 0 to 10%. A core-sheath composite spun yarn characterized by being produced.

(2) The two short fiber bundles A and B are placed in a ring spinning machine having a front top roller and a front bottom roller, each of which has a pair of tapered rollers whose draft ratio gradually increases in the width direction of the fiber bundle. The core-sheath type according to (1), wherein the short fiber bundles B having a high draft ratio are sequentially wound around the short fiber bundles A having a low draft ratio, and have a real twist. Composite spun yarn.

(3) The ratio of the short fiber bundle A is 25% to 75%
%, And the ratio of the short fiber bundle B is 75% to 25% by weight. The core-sheath composite spun yarn according to the above (1) or (2),

(4) One or more core-in-sheath composite spun yarns having a lower twist coefficient of 2.1 to 4.6 are used, and are plied at an upper twist return percentage of 40% to 90%. The above (1)
The core-sheath composite spun yarn according to any one of (1) to (3).

(5) The number of loops composed of the short fiber bundle B is twice the number of twists, and the loop radius is 3.5 to 8.0 times the apparent diameter of the composite twin yarn before the boiling water treatment. The core-in-sheath composite spun yarn according to any one of (1) to (4) above,

(6) A fabric using the core-sheath composite spun yarn according to any one of (1) to (6).

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION In the core-sheath type composite spun yarn of the present invention, the short fiber bundle A of the core component is made of high shrinkage short fibers of polyester or polyacryl, and the short fiber bundle B of the sheath component is low shrinkage short fibers. It is composed of

Such a core-sheath type composite spun yarn is supplied to a ring spinning machine having a front top roller and a front bottom roller comprising a pair of tapered rollers whose draft ratio gradually increases in the width direction of the fiber bundle. The short fiber bundles A and B are supplied, and the short fiber bundles B having a high draft ratio are sequentially wound around the short fiber bundles A having a low draft ratio so that the single fiber bundles A in the core portion are wrapped in a bundle. The thread is formed.

Hereinafter, the present invention will be described in detail.

The core-sheath type composite spun yarn of the present invention is made into a composite yarn by adding the difference in short fiber shrinkage of the core-sheath component and the difference in the feeding amount of the front roller of the spinning machine. An important feature is that the value of is extremely large.

First, the short fiber bundle A constituting the core of the core-sheath composite spun yarn of the present invention will be described.

The short fiber bundle A constituting the core portion is a fiber bundle of high shrinkage polyester short fiber or high shrinkage polyacrylic short fiber having a hot water shrinkage of 20 to 40%, and is not particularly limited. Hot water shrinkage ratio is 30 to increase
~ 40% is good. In addition, conjugate tow such as bimetal method that spins undiluted solutions having different viscosities at the same time is designed to achieve high shrinkage by drawing tow by drawing spinning.
It may be one that assists in the development of shrinkage and stabilizes the contraction rate higher.

The polyester staple fiber used in the present invention is:
Melt-spinnable polyester polymers such as polyethylene terephthalate and polybutylene terephthalate. These polymers may include, if necessary, tertiary polymers such as isophthalic acid, polyethylene glycol and polytetramethylene glycol.
One or several kinds of components may be copolymerized. For example, those having a breaking elongation in the range of 10 to 40% are preferable.

The polyacrylic short fibers used in the present invention have a tensile strength of 2.5 to 4.5 g / d and an elongation at break of 25 to 4.5 g / d.
It is a commercially available high-shrink polyacrylic or high-shrink polyacrylic synthetic fiber having physical properties of 45%.

In the core-sheath composite spun yarn of the present invention, the ratio of the high shrinkage fibers of the short fiber bundle A in the spun yarn is 25 to 7%.
A range of 5% by weight is good. If the content is less than 25% by weight, the ratio of the high-shrink short fibers is too low, and the shrinkage is weak, so that it is difficult to obtain a stable shrinkage, and it is difficult to obtain a satisfactory loop.

On the other hand, if it exceeds 75% by weight, the shrinkage force is strong and a stable shrinkage rate can be obtained, but the sheath component of the loop-forming component is reduced, and it is difficult to obtain the desired bulkiness and the desired size of the loop shape. Become.

In order to make the loop shape bulky and stable, the ratio of the short fiber bundle A constituting the core is preferably in the range of 40 to 60% by weight.

In order to uniformly wrap high-shrinkage polyester short fibers or high-shrinkage polyacrylic short fibers, the short fiber bundle A and the short fiber bundle B should be equal or slightly thinner when the short fiber bundle A and the short fiber bundle B are combined. When the ratio of the polyester fiber or the polyacrylic fiber of the short fiber bundle A is set to 40 to 50% by weight, the composite spinning processability is improved, the loop shape is stabilized and the bulkiness is increased, which is more optimal.

Next, the short fiber bundle B constituting the sheath of the core-sheath composite spun yarn of the present invention will be described.

The short fiber bundle B constituting the sheath portion is a low-shrinkage short fiber having a hot water shrinkage of 10% or less, preferably 0 to 10%. It may be fiber wool, cotton, silk or hemp. The short fiber bundle B is a fiber bundle constituting a loop, and is not particularly limited.
To make the loop bulky and bulky, the hot water shrinkage is 0 to
3% is better.

The cross-sectional shape and single fiber fineness of the short fiber bundle A and the short fiber bundle B in the present invention are not particularly limited. The fiber length is also not particularly limited in accordance with the spinning method, but it is preferable that the short fiber bundle A and the short fiber bundle B have the same fiber length in view of the quality of the spun yarn.

The number of ply twists of the spun yarn of the present invention is determined by a twist coefficient K
(Twisting number = K × Count ^1/2 ) and a range of 2.1 to 4.6 is preferable. If K is smaller than 2.1, bulkiness can be obtained, but operability is deteriorated due to yarn breakage. If it exceeds 4.6, it becomes a strong twist, the yarn is tightened, and it becomes difficult to increase the bulkiness and the loop shape. Although not particularly limited, the twist coefficient K is in the range of 2.7 to 3.7, the bulkiness,
It is better in terms of the size of the loop shape and operability. The twist is twisted in the direction opposite to the twist direction of the lower twist, that is, so-called reverse twist is applied, and the number of the upper twists is preferably 40 to 90% of the lower twist number. 40
%, Primary twist due to insufficient primary untwisting is high, and the double yarn of the composite yarn is tightened, making it difficult to obtain bulkiness.
%, The twist becomes strong, the double yarn of the composite yarn is tightened, and poor loop formation and insufficient bulkiness occur. The number of upper twists is 50 to 70% of the number of lower twists due to the size of the loop shape, bulkiness, etc.
Is more preferred.

The loop size of the composite yarn of the present invention is preferably 3.5 to 8.0 times the apparent diameter of the composite yarn. If it is less than 3.5 times, the bulkiness is inferior, and if it exceeds 8.0 times, the bulkiness is good, but the short fiber binding force of the composite yarn is weakened, the yarn strength of the composite yarn is low, and it cannot be used. come. Bulky,
The size of the loop is more preferably 4 to 6 times the apparent diameter of the composite yarn from the viewpoint of the loop shape, post-processability, and the like.

The number of loops is preferably twice as many as the number of upper twists since the appearance of loops is regular. If it is smaller than twice, the appearance of loops becomes irregular, resulting in poor bulkiness. On the other hand, if it is more than twice, the loop shape becomes small, which is not preferable.

Further, by using the above-described composite spun yarn of the present invention to form a fabric such as a woven or knitted fabric, a fabric having a high bulkiness and a high fashionability can be obtained. The woven fabric is preferably used for the weft from the viewpoint of processability, and it is preferable to use 20 to 50% by weight of the woven fabric. The knitted fabric is 10 to 1 depending on the application.
It is preferable to use 00% by weight.

Next, a method for producing the core-sheath composite spun yarn of the present invention will be described.

Although the production method is not particularly limited,
For example, a preferred method for producing the core-sheath composite spun yarn of the present invention has the following configuration.

That is, two short fiber bundles A and B are supplied to a ring spinning machine having a front top roller and a front bottom roller composed of a pair of tapered rollers whose draft ratio gradually increases in the width direction of the fiber bundle. Then, the short fiber bundle B after the aprondraft passed through the high feed side of the front roller via the guide, and the short fiber bundle A after the aprondraft passed through the low feed side of the front roller were simultaneously spun and drafted. A short fiber bundle B having a high draft ratio is sequentially wound around a short fiber bundle A having a low magnification, and yarn is formed in a state where the short fiber bundle A of the core portion is wrapped in a twisted shape. The obtained composite spun yarn is a core-sheath type composite spun yarn having a real twist, and more preferably, two or more of the spun yarns are aligned and twisted at 40% to 90%.

FIG. 1 is a schematic view showing an example of an apparatus for producing a core-sheath composite spun yarn of the present invention.

In FIG. 1, a short fiber bundle A and a short fiber bundle B supplied to a spinning machine are respectively supplied to a back roller 3 and are gripped by a pair of tapered front rollers 5 and 6 via an apron draft 4. At this time, the short fiber bundle B is supplied via the trumpet 1 to the side of the front rollers 5 and 6 where the feed amount is high, and the short fiber bundle A via the trumpet 2 to the side where the front roller is low. The two components that have been gripped by the front roller are combined, real-twisted with a ring and a traveler, and wound around a yarn tube in a usual manner.

As shown in FIG. 1, the front bottom roller 6 is tapered one by one corresponding to the spindle.

These tapered front bottom rollers 6
A pair of top rollers having the same taper direction and surfaces made of rubber cots are mounted on a penjoram arm in the same manner as the conventional top rollers to apply a load. The top roller 5 is provided with a rubber cot on the surface, and has the same direction as the bottom roller taper portion. The taper angle may be the same as the bottom taper angle, and the working width may be the same as or slightly smaller than the bottom taper width.

As described above, the bottom roller and the top roller composed of a pair of tapered rollers are mounted, and the sliver and the roving are gripped by a usual method. The draft changes along the fleece width direction, and the short fiber bundle B gripped by the large diameter portion is sequentially wound around the short fiber bundle A gripped by the small diameter portion to obtain a core-sheath type composite spun yarn. it can.

The fleece of the rovings A and B is preferably controlled by a collector or the like.

The ratio of the high shrinkage polyester short fibers or the high shrinkage polyacrylic short fibers of the short fiber bundle A of the core component in the whole core-sheath composite spun yarn is 25 to 7%.
The thickness of the short fiber bundle A and the short fiber bundle B composed of the low shrinkage fibers are selected so as to be in the range of 5% by weight, and the distance between the two fiber bundles is about 3 to 15 mm at the same time by a ring spinning machine. By spinning, the core-sheath composite spun yarn of the present invention can be obtained. The degree of these intervals changes the difference between the feed amounts of the two components, that is, changes the winding state of the short fiber bundle B, and is determined by considering the overlapping state, operability, and physical properties of the composite twin yarn after hot water treatment. Good.

Furthermore, the fiber bundle of the high-shrinkage polyester short fiber or the high-shrinkage polyacrylic short fiber constituting the short fiber bundle A of the present invention may be a sliver or a roving produced through a usual spinning method. The system is not particularly limited, and the core-sheath composite spun yarn can be obtained by re-twisting the obtained core-sheath composite spun yarn at 40% to 90%.

[0045]

The present invention will now be described more specifically with reference to examples.

The method of measuring characteristic values and the like in the examples is as follows.

1. Number of Loops FIG. 2 is a side view of a loop yarn, and a loop from a peak a to a next peak b is counted as one loop.

2. Loop radius ratio FIG. 3 is a side view of the composite yarn twin yarn before the boiling water treatment. The length from the center of the composite yarn to the outermost layer portion of the apparent outer periphery of the composite yarn is c, and the loop from the center of the loop yarn in FIG. The length up to the outermost layer is d.

Let d / c = loop radius ratio.

3. Bulkiness The loop-like composite yarn twin yarn was treated as boiling water and treated with boiling water, and then dried.

◎: excellent bulkiness, ○: slightly bulky, Δ: normal, ×: poor bulkiness. Sensory evaluation of knitting fabric feeling A 12-knit flat knitting machine was used to create a knitted fabric with single yarn supply of 20S / 2.

◎: soft and excellent in texture, ：: slightly soft, Δ: normal, ×: inferior texture [Examples 1 and 2] As Example 1, the fineness was 1.5 d. A high-shrink polyester short fiber 100% having a fiber length of 51 mm and a boiling water shrinkage of 30% was produced by a usual spinning method to a thickness of 0.5 g / m.
Was made. On the other hand, fineness 1.5d, fiber length 51m
100% low shrinkage polyester short fiber with m boiling water shrinkage of 2%
By the same spinning method, roving having a thickness of 0.5 g / m was prepared.

The two rovings were set on a 2-inch ring spinning machine having a pair of front taper rollers.
A low-shrinkage polyester short fiber 100% roving is supplied from the back roller to the side where the front roller feed amount is high through a trumpet, and a roast yarn including high shrinkage polyester short fiber 100% to the front roller low feed amount side, Supplied through trumpet. The total spinning draft is 34.1 times, and the core-sheath type composite spun yarn count is 2
0S (cotton count), twist factor K = 2.7 (12.1T /
in) Z twist. The fleece interval of each roving is drafted and united at 5 mm, then wound into a yarn tube by a usual method, and a core / sheath composite spinning of 50/50 high shrinkage polyester fiber 50% / low shrinkage polyester fiber 50/50 core / sheath ratio A yarn was obtained (Example 1).

As in Example 2, as in Example 1, 100% low-shrink polyacrylic short fibers having a fineness of 1.5 d, a fiber length of 51 mm, and a shrinkage factor of 4% in boiling water, and a roving of 0.5 g / m were rolled on a front roller. To the side with higher feeding amount, on the other hand, fineness 1.5
d, 100% of high-shrink polyacrylic short fibers having a fiber length of 51 mm, a boiling water shrinkage of 23%, and a roving of 0.5 g / m are supplied to the side where the front roller feed amount is low, respectively.
A composite spun yarn with S, K = 2.7 was obtained (Example 2).

Two of these various composite spun yarns are aligned and re-twisted at 60% (7.3 T / in) S by a ring twisting machine.
190cm × 2 as twin yarn by twisting and twisting
After making 00 g of casserole, the mixture was subjected to boiling water treatment at a usual bulky casserole dyeing temperature (100 ° C. × 30 min) to obtain bulky casserole. The obtained bulky yarn was measured and evaluated for the number of loops (pieces / in) and the loop radius with a magnifying glass. Also, using this bulky yarn, a 12-gauge flat knitting machine was used to create a knitted fabric and produced by five people. Table 1 shows the results of the knitted fabric sensory evaluation. The knitted fabrics of Example 1 and Example 2 were excellent in bulkiness, large in loop radius, beautiful in appearance, and excellent in fashionability.

[Examples 3 and 4] A single yarn of the core-in-sheath composite spun yarn 20s obtained in Example 1 was twin-aligned and re-twisted 50% (Example 3) and 85% (Example 3) by a ring twisting machine. After preparing Example 4), each was bulky and treated with boiling water in the same manner as in Example 1 to obtain respective bulky cases. Using the obtained bulky case, a single yarn feeder and a knitted fabric were prepared with a 12 gauge flat knitting machine, and the knitted fabric sensory evaluation was conducted by five persons.
Shown in

Examples 3 and 4 were excellent in bulkiness, large in loop radius, beautiful in appearance and excellent in knitted fabric. The results are shown in Table 1.

Example 5, Comparative Example 1 A high shrinkage polyacrylic short having a fineness of 1.5 d, a fiber length of 51 mm and a boiling water shrinkage of 38% (Example 5) and a boiling water shrinkage of 18% (Comparative Example 1). A 100% fiber and a 0.4 g / m roving are produced, respectively, and the fineness of 1.5 d,
Composite spinning with a 20S twist factor of 2.7 by feeding 100% of low-shrink polyacrylic short fibers with a fiber length of 51mm and boiling water shrinkage of 3% and roving of 0.6g / m to the side where the front roller feed amount is high. Yarns were prepared, double twisted at 60% top untwisting and then subjected to knurling and bulky processing. The obtained bulky yarns were measured and evaluated for the number of loops and loop radius with a magnifying glass. The results are shown in Table 1. Further, a single yarn feeder and a knitted knitted fabric were prepared by a 12 gauge flat knitting machine, and the knitted fabric sensory evaluation was performed by five persons. Comparative Example 1 had a very small loop diameter ratio of 2.2 times and was inferior in bulkiness. The results are shown in Table 1.

[Examples 6 and 7] Using the same high-shrinkage and low-shrinkage rovings used in Example 1, the high-shrinkage roving was moved to the lower side of the spinning front roller, and the low-shrinkage roving was changed to the front roller. To the higher side of the feed rate of
(Example 6) A bulky yarn obtained by preparing a composite yarn according to 4.6 (Example 7), twisting and retwisting by 60% each to form a scallop and then performing a boiling water treatment to obtain a bulky yarn. The number of loops and the radius of the loop were measured and evaluated using a magnifying glass, and a knitted fabric was prepared by using this bulky yarn with one 12-gauge flat knitting machine to perform a knitted fabric sensory evaluation.

Examples 6 and 7 are knitted fabrics having a large loop radius and a large bulk and excellent texture, and Example 6 is soft and optimal for baby clothing.

[Comparative Example 2] Fineness 1.5d, fiber length 51m
m, high shrinkage polyacrylic short fiber 1 having a boiling water shrinkage of 30% 1
A roving of 00% and 0.5 g / m 2 is prepared, and the fineness is 1.5 d and the fiber length is 51 m to the lower side of the front roller feeding amount.
m, low shrinkage polyacrylic short fiber 1 having a boiling water shrinkage of 12%
00% and 0.5 g / m of the roving yarn are supplied to the side where the front roller feed amount is higher, respectively, to produce a composite spun yarn having a 20S twist coefficient of 2.7. Was evaluated in the same manner as in Example 1. Comparative Example 2 had a small loop radius and low bulkiness. Table 1 shows the results
Shown along with.

[0062]

[Table 1]

[0063]

As described above, the loop-shaped bulky core-sheath composite spun yarn of the present invention uses a 2-inch ring spinning machine having a pair of front taper rollers, and comprises a high shrinkage polyester fiber and a polyacrylic core constituting a core. A fiber bundle of fibers,
Low-shrinkage polyester fiber or low-shrinkage polyacrylic fiber that composes the sheath part is uniformly coated, and the sheath fiber is converged by suitable twist-back by twin yarn processing to form a loop. It is possible to obtain a material that can be provided to the field of clothing, interior, and industrial materials with a variety of wearing and appearance changes.

[Brief description of the drawings]

FIG. 1 is a schematic view showing an example of an apparatus for producing a core-sheath composite spun yarn of the present invention.

FIG. 2 is a side view of a loop yarn after a boiling water treatment showing an example of a core-sheath composite spun yarn of the present invention.

FIG. 3 is a side view of a composite twin yarn of a loop yarn before a boiling water treatment, showing an example of a core-sheath type composite spun yarn of the present invention.

[Explanation of symbols]

 1: Trumpet 2: Trumpet 3: Back roller 4: Apron draft 5: Tapered front top roller 6: Tapered front bottom roller

Claims (6)

[Claims] 1. A core-sheath type composite spun yarn, wherein a short fiber bundle A of a core component is composed of a high shrinkage polyester short fiber or a high shrinkage polyacrylic short fiber having a hot water shrinkage of 20% to 40%. A core-sheath composite spun yarn wherein the short fiber bundle B of the component is composed of low shrinkage short fibers having a hot water shrinkage of 0 to 10%. 2. The two short fiber bundles A and B are supplied to a ring spinning machine having a front top roller and a front bottom roller composed of a pair of tapered rollers whose draft ratio gradually increases in the width direction of the fiber bundle. The core-sheath type composite spinning according to claim 1, wherein the short fiber bundle B having a high draft ratio is sequentially wound around the short fiber bundle A having a low draft ratio, and has a real twist. yarn. 3. The core-sheath composite according to claim 1, wherein the ratio of the short fiber bundle A is 25% to 75% and the ratio of the short fiber bundle B is 75% to 25% by weight. Spun yarn. 4. The use of one or more core-sheath composite spun yarns having a lower twist coefficient of 2.1 to 4.6, and a retwist percentage of 40%
The core-sheath composite spun yarn according to any one of claims 1 to 3, wherein the spun yarn is twisted at 90%. 5. The number of loops composed of the short fiber bundle B is twice the number of twists, and the loop radius is 3.5 to 8.0 times the apparent diameter of the composite twin yarn before boiling water treatment. A core-sheath composite spun yarn according to any one of claims 1 to 4. 6. A fabric using the core-sheath type composite spun yarn according to any one of claims 1 to 6.