JP2016138352A - Long and short composite spun yarn - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a long and short composite spun yarn that has soft touch feeling despite use of polyester-based fiber and has many functions such as water-absorbing and diffusing property that is not achieved by natural fibers and cellulosic fibers.SOLUTION: A long and short composite spun yarn is a composite spun yarn in which 60 to 80 mass% of polyester-based staple fibers having a flat multifoliate cross section are arranged at a sheath side, and 20 to 40 mass% of polyester-based multifilament fibers are arranged at a core side. For the polyester-based staple fiber having a flat multifoliate cross section arranged at a sheath side, a projected part ratio (E/B) is in a range of 0.6 to 0.9, where maximum length A of a cross section thereof is a symmetry axis is and E is a longest length, with the exception of maximum width B of the cross section thereof, among the line segments between projected part peaks facing each other.SELECTED DRAWING: Figure 2

Description

  The present invention relates to a long and short composite spun yarn having a water-absorbing diffusibility, in which an irregular cross-section polyester short fiber is arranged on the sheath side and a polyester multifilament fiber is arranged on the core side, and particularly has a soft texture. The present invention relates to long and short composite spun yarns that can obtain good fabrics for clothing, specifically inner shirts, outer shirts, and pants.

  Conventionally, there has been proposed a fabric having a drape and a dry feeling, and having good anti-scaling properties and UV by using a core-sheath polyester flat cross-section fiber for uniforms, sports, outerwear, or industrial materials. (See Patent Document 1). Specifically, a yarn has been proposed in which the number of convex portions of the polyester flat cross-section fiber is 3 to 6, and the uneven portion of the flat outer peripheral portion is uniform. However, when the number of convex portions of the polyester flat cross-section fibers is less than 6, there are less voids formed between adjacent fibers, resulting in poor water absorption and fluid replenishment. Moreover, in this proposal, the uneven | corrugated height of a flat-shaped outer peripheral part is made uniform, it cannot have a space | gap of various sizes between fibers, and cannot have the outstanding water absorption, quick-drying property, and softness.

  Separately, a multi-leaf type polyester fiber is proposed in which the polyester is a copolymer composed of a dicarboxylic acid component and a glycol component, and the cross-sectional lateral shape is a multi-leaf shape (see Patent Document 2). However, this proposal has a problem that although the polyester fiber is excellent in dyeability, the degree of deformity is as low as 0.05 to 0.08, and the fiber may be easily damaged by rubbing.

  Further, it is characterized in that flat odd-shaped cross-section polyester short fibers are blended with 20% by weight or more, single fiber fineness is 1.5 to 5 denier, and round cross-section polyester short fibers having a round fiber cross section. A spun yarn has been proposed (see Patent Document 3). However, this proposal does not have a glittering feeling, has a soft touch, is stretchy, and can have a refreshing hemp / rayon-like texture, but it is a mixed spinning and it is difficult to improve the water absorption and quick drying effect There is a problem of being.

  In addition, it blends 20-80% flat cross-sectional polyester fibers and 20-80% cellulose fibers, and has high absorbency, quick-drying and anti-scaling functions that cannot be achieved with natural fibers and cellulosic fibers alone. A spun yarn has been proposed (see Patent Documents 4 and 5). However, in these proposals, water absorption and quick-drying can be obtained by using the flat multi-section polyester-based fiber, but there is a problem that it is a blended fiber and there is a possibility that rapid quick-drying cannot be obtained.

JP 2013-44055 A JP 2012-136810 A JP-A-8-60470 International Publication WO2014 / 132690 International Publication WO2014 / 156451

  Therefore, the object of the present invention is to use a polyester fiber that could not be achieved by the above-mentioned prior art, but has a soft texture, and furthermore, water absorption, diffusibility, and transparency that could not be achieved by natural fibers or cellulosic fibers. An object of the present invention is to provide a long and short composite spun yarn having many functions such as prevention, ultraviolet shielding and durability.

  As a result of earnestly studying the above problems, the present inventors have paid attention to the voids between the fibers. That is, in Patent Documents 1 and 2 described above, since there are few voids between the fibers, a sufficient effect on the water absorption diffusivity is not obtained. Regarding the water absorption diffusivity using irregular cross-section fibers, there is a concern that moisture will be retained as it is only with high unilateral water absorption, and the body will be cooled while wearing, It was found that the gap between the fibers is very important because quick drying can be expected by increasing the contact opportunity.

  In addition, in the proposal of Patent Document 3 described above, a spun yarn fabric having no glittering feeling, soft touch and tension, and a refreshing feeling and effective in water absorption can be obtained. Sex does not appear.

  In order to solve the above problems, the present inventors have adopted a composite spun yarn that uses a specific flat multi-leaf type cross-sectional polyester short fiber and preferably a polyester multifilament fiber having a large fineness, thereby absorbing water. Reached composite spun yarn with high diffusibility.

The present invention is to solve the above-mentioned problems, and the long and short composite spun yarn of the present invention is provided with 60 to 80% by mass of flat multileaf polyester short fibers on the sheath side and polyester on the core side. It is a composite spun yarn in which 20 to 40% by mass of multi-filament fibers are arranged, and the flat multi-leaf polyester short fibers on the sheath side face each other with the maximum length A of the cross section as the axis of symmetry. When the longest length excluding the transverse cross section maximum width B is E, the convex portion ratio (E / B) represented by the following equation (1) is 0.6 to A long and short composite spun yarn characterized by satisfying a range of 0.9.
・ Convex part ratio (E / B) (1)
According to a preferred embodiment of the long and short composite spun yarn of the present invention, the single fiber fineness of the flat multilobal cross-section polyester short fiber disposed on the sheath side is in the range of 1.5 to 4.0 dtex, and the cross-sectional shape is It is a flat shape having six or more convex portions on the circumference, the flatness (A / B) shown by the following formula (2) is 2.0 to 3.0, and the deformity shown by the following formula (3) (C / D) is 1.0 to 5.0, and the single fiber fineness of the polyester multifilament fiber disposed on the core side is in the range of 1.5 to 4.0 dtex, which is 1 than the single fiber fineness of the sheath. It has a fineness of 0.03 times or more and less than 3.0 times.
・ Flatness (A / B) (2)
・ Deformation degree (C / D) (3)
(However, A is the maximum length of the cross section of the flat multi-leaf polyester short fiber, B is the maximum width of the cross section of the flat multi-leaf polyester short fiber, and C is a line connecting the vertices of adjacent convex portions in the maximum uneven portion. And D represents the length of a perpendicular line extending from the line connecting the vertices of adjacent convex portions to the bottom of the concave portion in the maximum uneven portion.)
In the present invention, a fabric described later can be produced using the long and short composite spun yarn.

  According to the present invention, a long / short composite spun yarn having good water absorption and diffusibility can be obtained. Specifically, according to the present invention, while using polyester fiber, it has a soft texture, and furthermore, water absorption, diffusibility, see-through property, UV shielding property that could not be achieved with natural fiber or cellulosic fiber. And long and short composite spun yarns having many functions such as durability.

  Further, according to the present invention, it is possible to obtain a fabric excellent in water absorption and diffusibility using the long and short composite spun yarn of the present invention, and a woven or knitted fabric having a soft texture and good pilling properties. .

  The long / short composite spun yarn of the present invention is suitably used for apparel applications, in particular for fabrics such as inner shirts, outer shirts, pants, sports and knitted fabrics such as pants.

FIG. 1 is a cross-sectional view illustrating a cross-sectional shape of a flat multi-leaf cross-sectional polyester fiber provided in a long and short composite spun yarn of the present invention having a plurality of (eight) convex portions on the circumference of the fiber cross section. FIG. 2 is a cross-sectional view for illustrating the long and short composite spun yarn of the present invention.

  The long and short composite spun yarn of the present invention is a composite spun yarn comprising 60 to 80% by mass of a flat multileaf polyester short fiber on the sheath side and 20 to 40% by mass of a polyester multifilament fiber on the core side. The sheath-side flat multilobal cross-sectional polyester short fiber has the maximum length A of the cross section as the axis of symmetry, and excludes the cross section maximum width B from the opposing line segments between the vertices. When the maximum length is E, the long and short composite spun yarn satisfies the convex portion ratio (E / B) in the range of 0.6 to 0.9.

  Examples of the polyester constituting the flat multilobal polyester short fiber and the polyester multifilament fiber used in the present invention include polyethylene terephthalate, polybutylene terephthalate, polypropylene terephthalate, and copolymers thereof. A particularly preferably used polyester is polyethylene terephthalate.

  Next, flat cross-section polyester short fibers and polyester multifilament fibers used in the present invention will be described.

  First, the flat multilobal polyester short fiber is disposed on the sheath side of the long and short composite spun yarn of the present invention, and the short fiber is used because it exerts the effect of diffusing water absorbed by the fluff spreading outward. It is done. Moreover, although mentioned later for details, the cross-sectional short polyester fiber for many flats used by this invention is a flat-shaped fiber which preferably has a cross-sectional shape on a circumference with six or more convex parts. If the number of convex portions existing on the circumference in the cross-sectional shape is less than 6, voids formed between adjacent fibers are reduced, and water absorption, liquid retention, and diffusibility are poor. Further, since the cross-sectional shape is a flat shape, it is possible to form voids between the single fibers, and water absorption, liquid retention and diffusibility are improved. Furthermore, by arranging the flat cross-section polyester short fibers on the sheath side, the hair fallability per single fiber is improved, so that a soft texture can be obtained in the case of a fabric.

  In FIG. 1, an example of the single fiber cross-sectional shape of the flat multileaf cross-section polyester short fiber used by this invention is shown. FIG. 1 illustrates a cross-sectional shape of a flat multi-leaf cross-sectional polyester short fiber used in the present invention having a plurality of (eight) convex portions on the circumference of the fiber cross section.

  In FIG. 1, the maximum length A of the cross-section of the above-mentioned flat multi-leaf cross-section polyester short fiber and the maximum width of the cross-section of the flat multi-leaf cross-section polyester short fiber, and the convex portion that intersects the maximum length A perpendicularly The length B of the maximum line segment connecting the vertices is shown. In FIG. 1, the length C connecting the vertices of the adjacent convex portions in the maximum uneven portion, the length D of the perpendicular line extending from the line connecting the vertices of the adjacent convex portions in the maximum uneven portion to the vertex of the concave portion, The maximum length A, excluding the maximum width B, of the line segments between the opposite convex vertices, with the maximum length A as the axis of symmetry, is shown.

  The flat multilobal polyester short fiber used in the present invention is a flat polyester fiber having preferably 6 or more convex portions in the cross-sectional shape of the fiber, and the number of convex portions is more preferably 7 to 13. Yes, more preferably 8-12. Moreover, it is a preferable aspect that a convex part shape is a rounded shape from a viewpoint of the touch property.

The flat multilobal polyester short fiber used in the present invention has the maximum length A of the cross section as the axis of symmetry, and is the longest length excluding the maximum cross section width B among the opposing line segments between the convex portions. When E is E, it is important to satisfy the convex portion ratio represented by the following formula (1).
-Convex part ratio (E / B) = 0.6-0.9 ... (1).

  The convex portion ratio (E / B) indicates the ratio of the maximum width A to the maximum convex portion apex length excluding the maximum length A in the flat multilobal shape, with the maximum length A as the axis of symmetry. This is meaningful as an index for measuring the degree of distortion of a substantially elliptical shape obtained when a line connecting the vertices of the convex portions having the maximum widths B and E and the maximum length A is drawn. When the convex portion ratio is too small, the depth of the concave portion is reduced, and the cross-sectional shape thereof is infinitely approximate to a flat cross shape. Therefore, the capillary effect is reduced, and the water absorption and diffusibility tend to decrease. Moreover, when it touches skin, since it becomes close to a flat cross shape, the number of convex parts which contact is decreased and the touch feeling and softness tend to be reduced. Therefore, it is important that the convex portion ratio is 0.6 or more.

  On the other hand, when the convex portion ratio is too large, when the concave and convex portions of the fibers are polymerized, the portion where the concave portion is completely blocked increases, so that the voids are reduced, and the water absorption and diffusibility tend to decrease. Indicates. Moreover, when the skin is touched, the shape becomes a shape close to a flat hexagon, so that the number of convex portions in contact with the skin decreases, and the feeling of touch and softness tend to decrease. Therefore, it is important that the convex portion ratio (E / B) is 0.9 or less. The convex portion ratio (E / B) is preferably 0.6 to 0.9 from the above viewpoint, and more preferably, the convex portion ratio is 0.6 to 0.8 from the balance. More preferably, it is 0.7-0.8.

  The convex portion ratio (E / B) can be controlled by discharging at a temperature of 250 to 300 ° C. through a spinneret made of a special variant, and blowing and cooling air at a temperature of 10 to 25 ° C. it can.

Moreover, the flat multilobal polyester short fiber used in the present invention has a flat multilobal cross-sectional shape in the single fiber cross-sectional shape of the fiber in the flatness range represented by the following formula (2) and the following formula (3). It is a preferable embodiment that the range of the irregularity shown is satisfied.
Flatness (A / B) = 2.0 to 3.0 (2)
Deformity (C / D) = 1.0 to 5.0 (3).

  If the flatness is less than 2.0, it is difficult to obtain a soft texture in which the fibers fall down. On the other hand, when the flatness exceeds 3.0, the harshness is small and easy to wear, and the yarn-making property and the deformity tend to deteriorate. The flatness is more preferably 2.0 to 2.7, and still more preferably 2.0 to 2.5.

  Also, the degree of irregularity represents the size of the concave portion between the convex portions in the above-mentioned flat versatile shape, and when the value is large, the concave portion is small, and when the value is small, the concave portion is large. doing. When the degree of irregularity increases, the recesses become shallower and the gaps formed between the single fibers also become smaller, so the water absorption and diffusibility tend to decrease. Therefore, it is desirable that the degree of profile is 5.0 or less. On the other hand, when the degree of profile is too small, the concave portion of the fiber cross section tends to be bent, and the flat shape tends not to be maintained. Furthermore, in order to make it easy to receive the fiber damage by abrasion, there exists a possibility that skin may be damaged when it rubs with skin. Therefore, the degree of irregularity is 1.0 or more. The degree of irregularity is preferably in the range of 1.0 to 5.0 from the above-mentioned point, the degree of irregularity is more preferably in the range of 1.0 to 4.0 from the viewpoint of water absorption and diffusibility, and further flatness 2.0 to 4.0 is a more preferable embodiment from the viewpoint of balance of shape retention, water absorption and diffusibility.

  The flatness (A / B) and profile (C / D) are also discharged at a temperature of 250 to 300 ° C. through a spinneret made of a special profile, similar to the convex ratio (E / B). It can be controlled by blowing air at a temperature of 10 to 25 ° C. and cooling it.

  It is preferable that the single fiber fineness of the flat multilobal polyester fiber used in the present invention is 4.0 dtex or less. The single fiber fineness is more preferably 1.0 to 3.5 dtex, and still more preferably 1.2 to 3.5 dtex. If the single fiber fineness exceeds 4.0 dtex, the rigidity specific to the polyester fiber becomes strong, so that the stimulation of the touch feeling becomes strong and the soft texture may be impaired. Furthermore, since the gap formed between the fibers becomes too large, the capillary phenomenon is weakened, and the liquid diffusibility is lowered, so that the dry feeling and the refreshing feeling when touching the skin tend to be impaired. On the other hand, when the single fiber fineness is smaller than 1.0 dtex, the process passability in the fabric production process is deteriorated, and the productivity may be lowered.

  Moreover, it is preferable that the fiber length of the flat multi-leaf cross-section polyester short fiber used by this invention is 30-64 mm from a viewpoint of a high-order process (fiber removal of a fabric), More preferably, it is 35-51 mm.

  The flat multilobal polyester fiber used in the present invention can be produced, for example, by the following method.

  Through a spinneret made of a specially shaped hole that forms a flat multi-leafed cross-section having 3 to 8 short-axis slits perpendicular to the longest-axis slit and melted from polyester, having 400 to 1300 discharge holes, 250 Discharge at a discharge rate of 200 to 500 g / min at a temperature of ˜300 ° C., cool by blowing air at a temperature of 10 to 25 ° C. with a flow of 30 to 100 m / min, and then apply a spinning oil and take-off speed An undrawn yarn is obtained once by placing it in a can at 900 to 1700 m / min. Then, after converging these tow of undrawn yarn, the tow of the obtained undrawn yarn is dried for 15 to 30 minutes at a draw ratio of 2.0 to 7.0 times and a temperature of draw temperature of 80 to 165 ° C. It can be cut to obtain flat cross-section polyester fibers.

  Next, the polyester fiber disposed in the core used in the present invention is a long fiber (multifilament). If the polyester fiber disposed in the core is a blended yarn of short fibers, the fiber arrangement of the spun yarn is random in the production process and the water absorption and diffusion effect cannot be exhibited. By making the polyester fibers arranged in the core part into long fibers (multifilaments), the fibers are gathered, and a long and short composite yarn that can exhibit a water absorption and diffusion effect with a core-sheath structure can be obtained.

  The single fiber fineness of the polyester-based multifilament fiber disposed in the core used in the present invention is also preferably 4.0 dtex or less, and 1.03 times or more of the single fiber fineness of the flat multileaf polyester fiber. It is preferably less than 0 times. When the single fiber fineness of the polyester-based multifilament fibers arranged at the core is lower than 1.03 times the single fiber fineness of the flat multileaf polyester fiber, the capillary phenomenon becomes weak and the water absorption effect can be exerted, but the liquid When diffusibility falls, there exists a tendency for the dry feeling and the refreshing feeling at the time of touching skin to be impaired. In addition, when the single fiber fineness is smaller than 1.0 dtex or more than 3.0 times the single fiber fineness of the flat multileaf polyester fiber, the process passability in the fabric manufacturing process is deteriorated and the productivity is lowered. There is a fear.

  In addition, regarding the number of filaments and the total fineness of the polyester multifilament disposed in the core, the number of cross-sectional fibers of the long and short composite spun yarn is preferably 65 or more. When the number of cross-sectional fibers of the formed long / short composite spun yarn is 65 or less, there is a possibility that a problem such as the yarn being broken when passing through the process may occur, and productivity may be lacking.

  The cross-sectional shape of the single fiber of the polyester-based multifilament fiber used in the present invention can be a round cross section, a flat cross section, a triangular cross section, a multi-global cross section, an X-shaped cross section, and other irregular cross sections.

  The polyester multifilament fiber used in the present invention can be produced, for example, by the following method.

  The polyester is melted, and has discharge holes of 300 to 1300, and is discharged at a discharge rate of 200 to 500 g / min at a temperature of 250 to 300 ° C. through a spinneret consisting of holes forming a circle. After air at a temperature of 30 to 100 m / min is blown and cooled, a spinning oil agent is applied, taken at a take-up speed of 900 to 1700 m / min, and stored in a can to obtain an undrawn yarn. Then, after converging these tow of undrawn yarn, the tow of the obtained undrawn yarn is dried for 15 to 30 minutes at a draw ratio of 2.0 to 7.0 times and a temperature of draw temperature of 80 to 165 ° C. A wound drawn yarn can be obtained.

  The single fiber strength of each of the flat multilobal polyester short fibers and polyester multifilament fibers used in the present invention is preferably 1.5 to 4.0 cN / dtex. When the single fiber strength is lower than 1.5 cN / dtex, process defects such as yarn breakage are likely to occur in the fabric manufacturing process. On the other hand, when the single fiber strength is higher than 4.0 cN / dtex, the softness and the anti-pilling property are poor.

  The long and short composite spun yarn of the present invention is a composite spun yarn comprising 60 to 80% by mass of a flat multileaf polyester short fiber on the sheath side and 20 to 40% by mass of a polyester multifilament fiber on the core side. It is.

  When the mixing ratio of the flattened cross-section polyester short fibers used in the present invention is less than 60% by mass, the polyester-based multifilament fibers arranged in the core cannot be covered, and the water absorption and diffusion effect cannot be improved. Moreover, since the diffusive effect by a capillary phenomenon will become difficult to appear when the mixing rate of the cross-sectional polyester short fiber for many flats exceeds 80 mass%, the mixing rate of the cross-sectional polyester short fibers for many flats is 60-80 mass%.

  The long / short composite spun yarn of the present invention is a long / short composite spun yarn in which multifilament fibers and short fibers are integrated and twisted. When viewed from the cross section, the polyester-based multifilament fiber is placed inside the long / short composite spun yarn. Threads that are contained or are unevenly distributed around the periphery.

  FIG. 2 illustrates a cross-sectional view of the long and short composite spun yarn of the present invention. In FIG. 2, the polyester-based multifilament fibers F are included in the long and short composite spun yarns, or are unevenly distributed around the periphery. Specifically, in the case of the long and short composite spun yarn 1 of FIG. 2 (left end view), the polyester multifilament fiber F is covered with the flat multileaf cross-section polyester short fiber S in the cross-sectional shape of the long and short composite spun yarn. It is arranged on the core side of the (around) long and short composite spun yarn. Further, the cross-sectional shape of the long and short composite spun yarn of the present invention is not always provided with the polyester-based multifilament fiber F arranged on the core side as indicated by 1 (left end portion) in FIG. As shown in 2 (center view) and 3 in FIG. 2 (left end view), the cross-sectional arrangement of the polyester-based multifilament fibers F may be randomly formed in the longitudinal direction of the long and short composite spun yarns. In the present invention, it is not important that the polyester-based multifilament fiber F is always arranged at the center of the cross section of the long and short spun yarn, and the polyester-based multifilament fiber F that is a core single fiber is gathered due to the capillary phenomenon. This is an important point in demonstrating water absorption and quick drying.

  When the core-sheath structure is formed in order to produce the long and short composite spun yarn of the present invention, the core-sheath structure can be formed by various processes such as a spinning machine, a roving machine, and a drawing machine.

Next, a method for producing the long and short composite spun yarn of the present invention will be described.
As a method of forming the long and short composite spun yarn of the present invention in which a polyester-based multifilament fiber is arranged on the core side and a flat multi-leaf polyester short fiber is arranged on the sheath side, the flat multi-leaf arranged on the sheath side first. The cross-section polyester short fiber is slived by a carding machine by a conventional method, and a sliver is formed by eliminating fine unevenness by a drawing and roving process. The step of mixing (mixing) the polyester-based multifilament fibers arranged on the core side with the flattened cross-section polyester short fibers is preferably performed in a spinning machine. If the polyester-based multifilament fiber and the flat multi-section polyester short fiber are mixed in the process before the spinning machine, the single fiber group arrangement may be lost in the stretched portion, and water absorption and diffusibility may not be exhibited. Polyester-based multifilaments, which are arranged on the core side in a spinning machine, are fed from the top of the front roller, overlapped with flat multi-leaf polyester short fiber bundles drafted on the nip line of the front roller, and added to the actual twist to add long and short composite spinning. Manufacture yarn.

  The count of the long and short composite spun yarn of the present invention is preferably 24 to 100 (English cotton count). If the count is thinner than 100, the number of cross-sectional fibers is small, resulting in poor productivity such as thread breakage during production. Moreover, when using for an inner material or a shirt material, it is preferable that it is 30-53rd, and it is a more preferable aspect that it is 30-40.

  The twist coefficient of the long and short composite spun yarn of the present invention is preferably in the range of 3.0 to 4.5. When the twist coefficient is less than 3.0, there is a tendency that sufficient yarn strength cannot be obtained, and there is a tendency that the yarn is broken during spinning or the strength is lowered when the knitted fabric is formed. Moreover, when the twist coefficient exceeds 4.5, there is a tendency that warpage due to twist return occurs, and there is a tendency that coarse and hard spaces appear when the cloth is made.

  The fabric using the long and short composite spun yarn of the present invention is preferably used as an inner shirt, an outer shirt, pants and the like.

  Next, the composite spun yarn of the present invention will be specifically described with reference to examples. Measurement and evaluation of characteristics and the like in the examples were performed by the following methods. The measurement method conforms to JIS L1095 (2010 edition). Moreover, the average value about 3 times of measurement was taken except the method shown to JIS by each physical-property value in an Example.

(1) Single fiber fineness and fiber length:
The measuring method of the single fiber fineness and the fiber length was performed according to JIS L1015 (2010 edition).

(2) Count:
The count method was performed in accordance with JIS L1095 (2010 edition).

(3) Water absorption evaluation of the fabric:
The water absorption evaluation of the fabric was performed in accordance with the measuring method of JIS L1907 (2010 edition, Bayrec method). The contents of the evaluation are as follows, and in the present invention, “◯” and “◎” were accepted.

◎: 80 mm or more ○: 70-79 mm
Δ: 50-69 mm
X: 49 mm or less.

(4) Fabric quick drying evaluation:
In the evaluation of the quick drying property of a fabric, a test piece left for 24 hours in a greenhouse at 25 ° C. and a humidity of 40% RH is cut into a 10 cm square and the mass (A) is measured. The test piece is immersed in ion-exchanged water for 30 seconds, and thereafter, one corner of the test piece is picked up with tweezers and taken out from the liquid. Similarly, the taken-out test piece is left to stand in an atmosphere of room temperature of 25 ° C. and humidity of 40% RH for 1 hour to dry naturally, and the mass (B) is measured. The residual moisture content (C) is calculated by the following formula.
・ C (%) = (B−A) / A × 100
The evaluation is as follows. In the present invention, “◯” and “◎” are regarded as acceptable.
A: 30% or less B: 31-40%
Δ: 41-50%
X: 51% or more.

(5) Texture (softness) evaluation:
In the texture evaluation, the test piece was cut out to 10 cm, and the five test subjects held the cut test piece, and the score was evaluated according to the following criteria, and then the average score was calculated. In the present invention, “◯” and “◎” are regarded as acceptable.
3 points: soft texture 2 points: slightly soft texture 1 point: hard texture ◎: 2.8 points or more ○: 2.4-2.7 points Δ: 1.9-2.3 points ×: 1.8 points Less than.

(6) Anti-pilling property evaluation:
The anti-pilling property was evaluated according to JIS L1076 (2012 version A method). Anti-pilling property was determined according to the following criteria. In the present invention, “◯” and “◎” are regarded as acceptable.
A: 4.5 grade or more B: 3.5-4 grade Δ: 2-3 grade x: 1.5 grade or less.

[Example 1]
(Method for producing flat multi-leaf polyester short fiber)
Spinning temperature of 290 ° C. from a flat multi-leaf sectional die (486 holes) having five short axis slits perpendicular to the longest axis slit by a melt spinning apparatus using polyethylene terephthalate (PET) (melting point 252 ° C.) After being discharged at 550 g / min, air at a temperature of 15 ° C. was blown at a flow of 40 m / min to cool, and then drawn at a speed of 1200 m / min to obtain an undrawn yarn. After converging the undrawn yarn, it was drawn at a draw ratio of 6.74 times and at a draw temperature of 90 ° C., crimped, partially dried at a temperature of 85 ° C., and then cut to produce a flat multileaf polyester short fiber. .

(Method for producing polyester multifilament)
Using polyethylene terephthalate (PET) (melting point 252 ° C.), a melt spinning device discharges from a round cross-section die (336 holes) at a spinning temperature of 290 ° C. at 415 g / min, and air at a temperature of 15 ° C. is 70 m. After being sprayed at a flow of / min and cooled, an undrawn yarn was obtained at a speed of 1300 m / min. After the undrawn yarn was converged, it was drawn at a draw ratio of 6.36 times and a draw temperature of 90 ° C. to produce a polyester multifilament.

The single-fiber fineness of the flat multi-leaf polyester short fiber having the sheath is 1.7 dtex, the fiber length is 51 mm, the flatness is 2.2, the deformity is 1.8, and the convex ratio is 0. .70, 70% by mass of fibers having a convex section with 8 cross sections, 30% by mass of polyester-based multifilament fibers having a single fiber fineness of 1.8 dtex and 24 cores, and a spinning machine (Toyota ring spinning machine RX240 type) was mixed to obtain a long and short composite spun yarn having a twist coefficient of 3.5 and an English cotton count of 40 s. Using the thus obtained long and short composite spun yarn for warp and weft, an air jet loom was used to obtain a plain weave having a warp density of 110 yarns / 2.54 cm and a weft density of 76 yarns / 2.54 cm. . The obtained plain weave was a woven fabric excellent in water absorption, quick drying, texture, and anti-pilling property. The results are shown in Tables 1 and 2.

[Example 2]
(Manufacturing method of flat multi-leaf polyester short fiber and polyester multifilament)
A flat multilobal polyester short fiber and a polyester multifilament were produced in the same manner as in Example 1.

  The single-fiber fineness of the flat multi-leaf polyester short fiber having the sheath is 1.7 dtex, the fiber length is 51 mm, the flatness is 2.2, the deformity is 1.8, and the convex ratio is 0. .8, 60% by mass of a fiber having 8 convex sections, 40% by mass of a polyester multifilament fiber having a single fiber fineness of 1.8 dtex and 33 cores, and a spinning machine (Toyota ring spinning machine RX240 type) was mixed to obtain a long and short composite spun yarn having a twist coefficient of 3.5 and an English cotton count of 40 s. Using the thus obtained long and short composite spun yarn for warp and weft, an air jet loom was used to obtain a plain weave having a warp density of 110 yarns / 2.54 cm and a weft density of 76 yarns / 2.54 cm. . The obtained plain weave was a woven fabric excellent in water absorption, quick drying, texture and anti-pilling property. The results are shown in Tables 1 and 2.

[Comparative Example 1]
The flat multilobal polyester short fiber has a single fiber fineness of 1.7 dtex, a fiber length of 51 mm, a flatness of 2.2, an irregularity of 1.8, and a convex ratio of 0.8. A spun yarn having an English cotton count of 40 s was obtained with 100% by mass of fibers having 8 convex portions and a twist coefficient of 3.5. Using this spun yarn for warp and weft, an air jet loom was used to obtain a plain weave having a warp density of 110 yarns / 2.54 cm and a weft density of 76 yarns / 2.54 cm. The obtained plain weave was a woven fabric excellent in water absorption, quick drying, texture and anti-pilling property. The results are shown in Tables 1 and 2.

[Comparative Example 2]
As the polyester fiber, the single fiber fineness is 1.7 dtex, the fiber length is 51 mm, the cross-sectional shape is a round round polyester short fiber, and the obtained round polyester short fiber has a twist coefficient. At 3.5, a spun yarn with an English cotton count of 40 s was obtained. Using this spun yarn for warp and weft, an air jet loom was used to obtain a plain weave having a warp density of 110 yarns / 2.54 cm and a weft density of 76 yarns / 2.54 cm. The obtained plain weave was a woven fabric excellent in anti-pilling property, but was inferior in water absorption, quick-drying and texture. The results are shown in Tables 1 and 2.

[Comparative Example 3]
The single-fiber fineness of the flat multi-leaf polyester short fiber having the sheath is 1.7 dtex, the fiber length is 51 mm, the flatness is 2.2, the deformity is 1.8, and the convex ratio is 0. And 40% by mass of fibers having 8 convex sections with a cross-sectional shape and 60% by mass of polyester-based multifilament fibers having a single fiber fineness of 1.8 dtex and 24 cores. Mixing (mixing) with a spinning machine, a long and short spun yarn with an English cotton count of 40 s was obtained with a twist coefficient of 3.5. A plain weave having a warp density of 110 yarns / 2.54 cm and a weft density of 76 yarns / 2.54 cm was obtained using the long and short spun yarns thus obtained as warp yarns and weft yarns using an air jet loom. The obtained plain weave was a woven fabric excellent in water absorption, quick drying and anti-pilling properties, but had a poor texture. The results are shown in Tables 1 and 2.

[Comparative Example 4]
The monofilament fineness of the flat multilobal polyester short fiber is 1.7 dtex, the fiber length is 51 mm, the flatness is 2.2, the profile is 1.8, and the convex ratio is 0.8. 70% by mass of fibers having 8 convex sections and 30% by mass of polyester short fibers having a single fiber fineness of 1.8 dtex and a fiber length of 51 mm in a blended cotton process, a twist coefficient of 3.5 A blended yarn of English cotton count 40s was obtained. Using the blended yarn thus obtained for warp and weft, a plain weave having a warp density of 110 yarns / 2.54 cm and a weft density of 76 yarns / 2.54 cm was obtained using an air jet loom. The obtained plain weave was a woven fabric excellent in water absorption, quick drying and anti-pilling properties, but had a poor texture. The results are shown in Tables 1 and 2.

A: Maximum length of the cross section of the flat multilobal cross section polyester short fiber B: Maximum width of the cross section of the flat multileaf cross section polyester short fiber C: Length D of the line connecting the apexes of the adjacent convex sections in the maximum concave section The length of the perpendicular line from the line connecting the vertices of adjacent convex parts to the bottom of the concave part in the largest uneven part

Claims (3)

A long / short composite spun yarn in which 60 to 80% by mass of flat multi-leaf polyester short fibers are arranged on the sheath side and 20 to 40% by mass of polyester multifilament fibers are arranged on the core side. The multi-leaf cross-section polyester short fiber has the maximum length A of the cross section as the axis of symmetry, and the longest length excluding the cross section maximum width B among the opposing line segments between the convex portions is E. When doing this, the long and short composite spun yarn characterized by the convex part (E / B) shown by following Formula (1) satisfying the range of 0.6-0.9.
・ Convex part ratio (E / B) (1) The flat multi-leaf cross-sectional polyester short fiber arranged on the sheath side has a single fiber fineness in the range of 1.5 to 4.0 dtex, and the cross-sectional shape is a flat shape having six or more convex portions on the circumference, The flatness (A / B) represented by the following formula (2) is 2.0 to 3.0, and the irregularity (C / D) represented by the following formula (3) is 1.0 to 5.0, And the single fiber fineness of the polyester multifilament fiber arranged on the core side is in the range of 1.5 to 4.0 dtex, and has a fineness of 1.03 to less than 3.0 times the sheath single fiber fineness. The long and short composite spun yarn according to claim 1, wherein
・ Flatness (A / B) (2)
・ Deformation degree (C / D) (3)
(However, A is the maximum length of the cross section of the flat multi-leaf polyester short fiber, B is the maximum width of the cross section of the flat multi-leaf polyester short fiber, and C is a line connecting the vertices of adjacent convex portions in the maximum uneven portion. And D represents the length of a perpendicular line extending from the line connecting the vertices of adjacent convex portions to the bottom of the concave portion in the maximum uneven portion.)   A fabric comprising the composite spun yarn according to claim 1 or 2.