KR20220073702A - Core Sheath Composite Fiber and Multifilament - Google Patents

Abstract

In the fiber cross section of the core sheath composite fiber made of two or more types of polymer, the sheath component completely covers the multilobed core component having three or more convex portions, and the ratio Smax/ A multifilament comprising a core-sheath composite fiber having an Smin of 5.0 or more, and a core component of the core-sheath composite fiber. To provide a core-sheath composite fiber and multifilament suitable for obtaining a good textile close to natural silk.

Description

Core Sheath Composite Fiber and Multifilament

The present invention relates to a core-sheath composite fiber and multifilament suitable for obtaining a textile having a natural silk-like high-quality luster, light, flexible and repulsive.

Synthetic fibers made of polyester, polyamide, or the like have excellent mechanical properties and dimensional stability, and are therefore widely used from medical applications to non-medical applications. However, these days, people's lives have been diversified and a better life has been demanded, and a high level of texture and function, which is not found in conventional synthetic fibers, is required in many applications including medical care.

If we look at the evolution of technological development related to synthetic fibers, it is not an exaggeration to say that each element technology has evolved with the motivating imitation of the features of natural materials. This is because natural fibers such as hemp, wool, cotton, and silk have excellent texture and function, and the complex luster and texture they weave are attractive and high-quality because humans feel them.

In the history of synthetic fibers that have imitated natural materials in this way, in particular, regarding silky materials that aim to achieve the characteristics of silk (hereinafter referred to as natural silk), the highest grade of natural materials, the fiber cross-sectional shape was designed from polymer technology. In addition, there are proposals for a wide range of textile technology, including spinning technology such as mixing two fibers.

For example, if the cross-sectional shape of a polyester fiber that reflects light relatively highly is made into a multi-leaf-shaped heterogeneous cross-section, the reflection of light is amplified by the irregularities of the multi-leaf shape, so that it becomes a fiber with high luminance and mild luster like natural silk. It is known and is produced in large quantities as a representative example of a silky material. However, there are cases where it is difficult to satisfy the texture of natural silk other than gloss (dry feeling, lightness, softness, repulsion, etc.) only by making a simple deformable cross-section, and by further complicating the cross-sectional shape, the texture of natural silk is pursued. Several fiber technologies are disclosed for one composite fiber.

Patent Document 1 proposes a composite fiber having a multi-leaf shape in a fiber cross-section, and a composite fiber in which a dissolving component is disposed at the apex of the multi-leaf shape in a tapered shape in the inner direction of the fiber. In the composite fiber, when the dissolving component is elution-treated, grooves are blended at the apex of the multi-leaf shape, so that the reflection of light by the multi-leaf shape and the increase in frictional force by the grooves give a high-quality gloss and dry feeling like natural silk. It is said that it is possible to reproduce the tactile feel and the scroop, which is a feature of textiles made of natural silk.

Patent Document 2 proposes a composite fiber obtained by dividing a hardly eluting component into a plurality of easily eluted components in a fiber cross section. In the above-mentioned composite fiber, when the dissolving component is elution-treated, one composite fiber is divided into a plurality of different cross-sectional fibers, so that the effect of reducing the diameter of fine fibers and the effect of reducing the cross-section are harmonized, giving a sense of quality like natural silk. It is said that it is possible to provide a soft feel in addition to the glossy and dry feel.

In addition, it is known that a silky woven knitted fabric is obtained by mixing fibers with a difference in shrinkage. is proposed. In the multifilament with the difference in shrinkage, a fiber made of co-polyester is used on one side, and when heat is applied, a difference in yarn length occurs between the fiber groups due to the difference in shrinkage, and the fabric is given abundant swelling, etc. to make it a silky material. saying that it is possible to do

Japanese Patent Laid-Open No. 57-5912 Japanese Patent Laid-Open No. 2010-222771 Japanese Patent Laid-Open No. Hei2-19528

As in Patent Document 1, by controlling light reflection and frictional force by forming a special cross-sectional shape using an eluting component, the high-quality luster unique to natural silk, dry touch, and unique durability can be reproduced to some extent. . However, in Patent Document 1, there are cases in which the voids between fibers are insufficient, and short fibers are formed in a dense form in the fabric. For this reason, when it is worn as clothes, the light and flexible feel which feels comfortable may be insufficient.

On the other hand, as in Patent Document 2, a method for imparting flexibility to a fabric by reducing the bending rigidity of each single fiber by reducing the diameter of fine fibers such as elution splitting is effective from the viewpoint of imparting flexibility. However, in Patent Document 2, the pores formed in the multifilaments are limited in some cases, and by making the yarn diameter thinner, the short fibers tend to be most closely filled depending on the fabric structure. For this reason, in order to achieve the light feel peculiar to natural silk, it is necessary to precisely design the fabric, etc., in some cases, limiting the development of the material.

In addition, the method of imparting swelling to the fabric by mixing fibers of different shrinkage as in Patent Document 3 is effective from the viewpoint of obtaining lightness due to swelling, but in terms of mixing each fiber at the time of taking-up or yarn processing, the fibers 's bias may occur. In the case where the fibers are biased in this way, for example, at locations where the fibers on the high-shrink side are unevenly distributed, shrinkage may occur and the soft feel may be impaired.

As described above, various technical proposals have been made so far as a silky material utilizing synthetic fibers, but there is a technology that expresses a feeling of light, flexible and repulsive in a balanced way while having a high-quality luster like natural silk. It is difficult to say that Therefore, it is an object of the present invention to provide a core-sheath composite fiber and multifilament suitable for solving the problems of the prior art and for obtaining a good textile close to that of natural silk.

The object of the present invention is achieved by the following means. in other words,

In the fiber cross section of the core sheath composite fiber made of two or more types of polymer, the sheath component completely covers the multilobed core component having three or more convex portions, and the ratio Smax/ core sheath composite fiber with Smin of 5.0 or higher;

Multifilaments composed of a core component of the core-sheath composite fiber of the above substrate;

Multifilaments having a pore structure in which the average inter-fiber void distance is 5 to 30 μm, and the proportion of which the inter-fiber void distance is less than 5 μm is 10 to 50%;

It is a fiber product in which the core-sheath composite fiber or multi-filament of the above-mentioned substrate is included in a part.

When the core-sheath composite fiber or multi-filament of the present invention is used, it is a unique feature in that fine inter-fiber voids of less than 5 μm and coarse inter-fiber voids of 10 μm or more are uniformly mixed between each fiber such as natural silk among multi-filaments. A pore structure can be formed, and a textile having a high-quality luster like natural silk, light, flexible, and repulsive can be obtained.

1 is a schematic diagram of a cross-sectional structure of raw silk extracted from a cocoon, which is the basis of natural silk.
Figure 2 (a) (b) is an example of a schematic diagram of the cross-sectional structure of the core-sheath composite fiber of the present invention.
3 (a) (b) (c) is an example of a schematic diagram of a cross-sectional structure of a composite fiber of the prior art.
4 (a) (b) (c) is an example of the schematic diagram of the cross-sectional structure of the core-sheath composite fiber of this invention.
5 (a) (b) is an example of the schematic diagram of the cross-sectional structure of the core-sheath composite fiber of this invention.
6 (a) (b) is an example of a schematic diagram of a cross-sectional structure of a composite fiber of the prior art.
7 is an example of a crimped form of the crimpable fiber constituting the multifilament of the present invention.
8 is an example of a schematic diagram of a cross-sectional structure of a multifilament of the present invention. (a) is a diagram for understanding "a uniform mixture", (b) is a diagram for understanding a method of measuring the average inter-fiber void distance.
9 (a) (b) is an example of a schematic diagram of the cross-sectional structure of the crimpable fiber constituting the multifilament of the present invention.
10 (a) (b) is a schematic diagram of a cross-sectional structure of an example of a core-sheath composite fiber capable of producing multifilaments of the present invention.
11 is a schematic diagram of a cross-sectional structure of an example of a composite fiber from which multifilaments of the prior art are producible.
12 is a cross-sectional view of a composite spinneret for explaining a method for manufacturing a core-sheath composite fiber and multi-filament of the present invention.

EMBODIMENT OF THE INVENTION Hereinafter, this invention is described in detail with preferred embodiment.

In pursuit of the principle of expression of the texture of natural silk, if we review the spinning process of natural silk, fibroin (Fig. It can be seen that a) has a cross-sectional shape of a fiber covered with sericin (FIG. In natural silk, a unique spinning process of eluting sericin from the raw yarn exists, and it is thought that the light and flexible texture unique to natural silk is created by the expression of voids between fibers by the elution of sericin.

In the conventional silky material, a method of forming voids between fibers by thinning fibers with a chemical such as alkali is often used. From the detailed observation of the silky material, it was found that there was a large difference in the size and distribution of the voids between the fibers formed between natural silk and conventional materials.

That is, in the case of natural silk, fine inter-fiber voids of less than 5 μm and coarse inter-fiber voids of 10 μm or more are uniformly mixed between single fibers, whereas in conventional materials, less than 5 μm or 10 μm or more. It was found that only voids between fibers that are biased toward either side can be formed, and the difference in void formation greatly affects the properties of the woven and knitted fabric.

This means that when the size of the inter-fiber voids is 10 µm or more, flexibility by being able to move the fixed fibers at the binding point of the woven/knitted fabric, or lightness by lowering the apparent density at high porosity, is obtained, while When the size of the pores is 5 μm or more, the feeling of repulsion is reduced due to the decrease in bending rigidity. Therefore, in conventional materials that can only form voids between fibers that are biased toward either less than 5 μm or 10 μm or more, there is a trade-off between lightness, flexibility and repulsion. relationship exists. On the other hand, in natural silk, in which coarse inter-fiber voids of 10 μm or more, which are responsible for lightness or flexibility, and fine inter-fiber voids, which are less than 5 μm, which are responsible for a feeling of repulsion, are uniformly mixed, this trade-off relationship is resolved and the product is light and flexible. In addition, a feeling of repulsion can be expressed in a well-balanced manner.

The present invention is constructed based on this idea, and in the composite fiber of the present invention for the purpose of forming a specific inter-fiber void exhibited by the natural silk, in the fiber cross section of the core-sheath composite fiber composed of two or more polymers, It is important that the sheath component completely covers the multi-leaf-shaped core component having three or more convex portions, which is the first requirement of the present invention.

The core sheath composite fiber as used in the present invention refers to a fiber composed of two or more types of polymers and having a cross-sectional shape in which a sheath component is provided so as to cover the core component in a cross section in a direction perpendicular to the fiber axis.

As the core component and sheath component constituting the core-sheath composite fiber of the present invention, since thermoplastic polymers are excellent in workability, the polymer group constituting the fiber includes, for example, polyester, polyethylene, polypropylene, polystyrene, Polyamide-based, polycarbonate-based, polymethyl methacrylate-based, polyphenylene sulfide-based polymer groups and copolymers thereof are preferred. It is preferable that all of the thermoplastic polymers used for the core-sheath composite fiber are the same polymer group and its copolymer from the viewpoint that particularly high interfacial affinity can be imparted and fibers having no composite cross-section abnormality are obtained. Moreover, from a viewpoint that it can be made into bending rigidity close|similar to natural silk and good color development property is obtained when dyeing, using it as a polyester-type combination is mentioned as a especially preferable range. In addition, various additives such as inorganic substances such as titanium oxide, silica and barium oxide, carbon black, colorants such as dyes and pigments, flame retardants, optical brighteners, antioxidants, and ultraviolet absorbers may be contained in the polymer.

Moreover, while attention is focused on environmental issues, the use of plant-derived biopolymers and recycled polymers in the present invention is also suitable from the viewpoint of reducing environmental load, and the polymer used in the present invention described above is chemical recycling and material. A recycled polymer that has been recycled can be used by either recycling or thermal recycling. Even when a biopolymer or a recycled polymer is used, the polyester-based resin can enhance the characteristics of the present invention as its polymer properties, and as described above, from the viewpoint of obtaining a flexural rigidity close to natural silk and good color development, as described above, recycled polyester can be suitably used in the present invention.

Here, an object of the core sheath composite fiber of the present invention is to obtain a multifilament composed of a core component by eluting the sheath component after high-order processing such as weaving or the like. For this reason, with respect to the solvent used for dissolution of the sheath component, it is preferable that the core component is poorly eluted and the sheath component is soluble. It is appropriate to select a candle component from the middle. At this time, it can be said that the higher the dissolution rate ratio to the solvent of the poorly dissolving component (core component) and the easily dissolving component (super component) is, the more suitable the combination, and the polymer may be selected based on the range of the dissolution rate ratio up to 3000 times.

As a super component, for example, polyester and its copolymers, polylactic acid, polyamide, polystyrene and its copolymers, polyethylene, polyvinyl alcohol, etc. can be melt-molded, and it is preferable to select from polymers exhibiting solubility and solubility compared to other components. Suitable. In addition, from the viewpoint of simplifying the dissolution process of the sheath component, the sheath component is preferably co-polyester, polylactic acid, polyvinyl alcohol, etc., which exhibit solubility in water-based solvents or hot water, etc. Because it exhibits solubility in solvents, fusion between the composite fibers does not occur even in false twist processing in which abrasion is imparted under heating, etc. Polyethylene glycol having a weight average molecular weight of 500 to 3000 in addition to the above-mentioned 5-sodium sulfoisophthalic acid and polyester copolymerized in the range of 5 wt% to 15 wt% are particularly preferred polymers.

In general, when the size of the inter-fiber voids increases, flexibility by being able to move the fixed fibers at the binding point of the woven/knitted material or the improvement of lightness by lowering the apparent density at high porosity are obtained, while bending as described above is obtained. A decrease in the sense of repulsion due to a decrease in rigidity also occurs. In order to resolve this trade-off relationship, it is important that coarse inter-fiber voids of 10 μm or more, which are responsible for the effect of improving lightness, and fine inter-fiber voids of less than 5 μm, which achieve both flexibility and repulsion, are mixed. For this purpose, in the core-sheath composite fiber of the present invention, it is necessary that the sheath component completely covers the multi-leaf-shaped core component having three or more convex portions.

If the sheath component completely covers the multi-leaf core component having three or more convex parts, the concave portion of the multi-leaf shape with a large super thickness forms coarse interfiber voids of 10 µm or more by super elution, while the sheath thickness is small. Since it is possible to form fine inter-fiber voids of less than 5 μm in the convex portion, it is possible to achieve a feeling of repulsion while having a light and flexible texture characteristic of natural silk. In addition, since the light reflection amplification effect is also obtained by forming the uneven portion on the surface of the fiber, it is possible to express not only high-brightness like natural silk, but also a high-quality luster such as a mild luster, and unevenness is formed on the surface of the fiber. , a dry feel can be obtained. From this point of view, as the number of convex portions increases, void formation between fibers, the effect of gloss, and dry feeling increase. A four-lobed shape having four convex portions such as a bar is preferable. However, when the number of concavo-convex portions increases too much, the distance between the concave-convex portions becomes dense, and the effect gradually approximates a round cross-section. Therefore, the practical upper limit of the convex portions of the multi-leaf shape of the seam component in the present invention is six.

In the composite fiber of the present invention, the ratio Smin of the minimum thickness Smin of the sheath component to the fiber diameter D from the viewpoint of forming fine interfiber voids of less than 5 μm as far as possible between neighboring short fibers by elution of the sheath component It is preferable that /D is a composite fiber of 0.01 or more.

In the present invention, the fiber diameter D means embedding the multifilament made of the core sheath composite fiber of the present invention with an embedding agent such as an epoxy resin, and the fiber cross-section in the direction perpendicular to the fiber axis is measured with a transmission electron microscope (TEM) of 10 or more An image is taken at a magnification where the fibers can be observed. At this time, if metal dyeing is performed, the contrast between the seam component and the sheath component can be made clear by using the dyeing difference between the polymers. From each photographed image, the diameter of randomly extracted fibers within the same image is measured to the first decimal place in μm, and this motion is obtained by rinsing 10 randomly extracted fibers and obtaining the simple number average of the results to place the first decimal place The value obtained by rounding up was taken as the fiber diameter D (μm). Here, when the fiber cross-section in the direction perpendicular to the fiber axis is not a perfect circle, a value obtained by measuring the area and converting to a circle is employed.

In the present invention, the minimum thickness Smin of the sheath component is, for example, any fiber surface from the center of gravity G1 of the core component 1 present on the fiber cross section as shown in Figs. A straight line is drawn toward the perimeter of the core component 1 and the distance S1 between the straight line intersection S1 and the fiber surface and the straight line intersection point F is calculated as the value measured to the first decimal place, and the smallest value among the obtained values is calculated. will be. A simple number average of the results of this operation for 10 randomly extracted fibers was rounded up to the first decimal place, and the minimum thickness Smin (µm) of the second component was taken. Here, for example, as shown in Figs. 4(a) and 5(b), on a straight line drawn from the center of gravity G1 of the seam component 1 toward an arbitrary fiber surface, a seam different from the seam component 1 taking the center of gravity When component 2 exists, the measured distance S1-S2 of the intersection S1 between the outer periphery of the seam component 1 and the straight line and the intersection S2 closest to S1 among the intersections of the outer periphery and the straight line of the seam component 2 was adopted. In addition, about the code|symbol in a figure, for example, G1 is the center of gravity of the shim component 1, G2 is the center of gravity of the shim component 2, G is their generic name, and it is the same about the other code|symbol.

Further, with respect to the obtained fiber diameter D and the minimum thickness Smin of the sheath component, a simple number average of the ratio (Smin/D) was calculated, and the value rounded up to the third decimal place was defined as Smin/D.

When the ratio of the minimum thickness Smin of the sheath component to the fiber diameter D is arranged such that the ratio Smin/D is 0.01 or more, in the obtained woven/knitted fabric, it is 5 as long as the fibers fixed at the binding point of the woven/knitted material can be moved by super elution. It is preferable because fine interfiber voids of less than μm can be expressed and a soft feel can be imparted. From this point of view, the higher the Smin/D, the larger the size of the fine inter-fiber voids of less than 5 μm, and the fibers are easier to move. It becomes possible to express also high drape property, and it is mentioned as a more preferable range. On the other hand, if the size of the inter-fiber voids is too large, the bending recovery property is also reduced, so that the sense of repulsion, which is one of the textures of natural silk, is impaired, so the practical upper limit in the present invention is 0.1.

As described above, in order to solve the trade-off relationship of a decrease in the feeling of repulsion against the improvement of flexibility or lightness due to the increase in the size of the interfiber voids, by making the core component into a multi-leaf shape, a multi-leaf-shaped recess with a large super thickness In this case, it is important to form coarse interfiber voids of 10 μm or more by super elution, while forming fine interfiber voids of less than 5 μm in convex portions with small super thicknesses, and the maximum and minimum interfiber void sizes It is important to control Therefore, as a result of intensive studies by the present inventors, if the ratio of the maximum and the minimum inter-fiber voids is within a certain range, there is a sufficient difference in the voids between the two fibers, so that the light, flexible and repulsive feel unique to natural silk can be excellent. found. That is, the second requirement is that the ratio Smax/Smin of the maximum thickness Smax to the minimum thickness Smin of the second component is 5.0 or more.

In the present invention, the maximum thickness Smax of the sheath component is, for example, the surface of any fiber from the center of gravity G1 of the core component 1 present on the fiber cross section as shown in FIGS. A straight line is drawn toward the periphery of the core component 1, and the distance S1-F between the perimeter of the core component 1 and the intersection point S1 of the straight line and the fiber surface and the straight line intersection point F is calculated as the value measured to the first decimal place, and the maximum value among the obtained values is calculated. . A simple number average of the results of this operation performed on 10 randomly extracted fibers was rounded up to the first decimal place, and the minimum thickness Smax (µm) of the second component was taken. Here, for example, as shown in Figs. 4(a) and 5(b), on a straight line drawn from the center of gravity G1 of the seam component 1 toward an arbitrary fiber surface, a seam different from the seam component 1 taking the center of gravity When component 2 exists, the measured distance S1-S2 of the intersection S1 between the outer periphery of the seam component 1 and the straight line and the intersection S2 closest to S1 among the intersections of the outer periphery and the straight line of the seam component 2 was adopted.

Further, for the obtained maximum thickness Smax of the second component and the minimum thickness Smin of the second component, a simple number average of the ratio (Smax/Smin) was calculated, and the value rounded up to the second decimal place was defined as Smax/Smin.

In the core-sheath composite fiber of the present invention, when the ratio Smax/Smin of the maximum thickness Smax of the sheath component in the coarse interfiber voids of 10 μm or more and the minimum thickness Smin in the fine interfiber voids of less than 5 μm is 5.0 or more, The light, flexible, and repulsive feel of natural silk can be sufficiently enhanced. In addition, when Smax/Smin is 10.0 or more, it is possible to form an interfiber pore size close to that of natural silk, and since lightness closer to that of natural silk is obtained, it is mentioned as a more preferable range. In addition, from the viewpoint of this lightness, a higher Smax/Smin is preferable. However, if Smax/Smin is high, the release degree of the deformable cross-section fiber obtained after elution of the sheath component increases, and when it is made into a fabric, high-order problems such as glare or streaks occur Also, the practical upper limit of Smax/Smin is 30.0.

The area ratio of the sheath component in the core sheath composite fiber of the present invention is preferably 10% to 50%. When the area occupied by the sheath component is increased, the effect of forming voids between fibers due to the elution of the sheath component is increased, preferably 10% or more, and more preferably 20% or more. In addition, while a higher area ratio of the sheath component is preferable from the viewpoint of voids between fibers, the practical upper limit is 50% in that there are cases where a decrease in strength due to excessive dissolution of the sheath component or a long time for dissolution treatment occurs.

In the core-sheath composite fiber of the present invention, the fiber cross-section is a perfect circle or an ellipse, and the fiber has an inscribed circle diameter RA (diameter of _A in Fig. 4(a)) and a circumscribed circle diameter RB (diameter of _B in Fig. 4(a)). It is preferable that the relationship of 1.0≤R _B /R _A≤2.5 . However, _{RB /R A as} used herein means the degree of irregularity of the fiber.

In the core sheath composite fiber of the present invention, it is important to mix voids between different fibers in the formation of a multi-leaf shape by super elution, and it is similarly changed before and after the dissolution of the sheath component as shown in FIGS. 3 (a) and (b). Not a core-sheath composite fiber, but a circle as in FIGS. 2(a), (b), 4(b), (c), or 5(a), or an ellipse as in FIGS. 4(a), 5(b) When a multi-lobed core component is used in the core-sheath composite fiber of the shape, it is preferable because interfiber voids of 10 µm or more and interfiber voids of less than 5 µm can be mixed. In addition, when RB /R _A indicating the degree of irregularity is 1.0≤R _B / _{R A≤2.5} , when the core-sheath composite fiber of the present invention exists as a multifilament, it is easy to fill the closest packing, so the fiber obtained after elution as a sheath component It is preferable from the viewpoint of quality control, since it is possible to make the interstitial voids uniform without non-uniformity.

In the core-sheath composite fiber of the present invention, in the multi-leaf-shaped core component from the viewpoint of emphasizing the dry feeling after the dissolution of the sheath component, a groove in the direction of the center of gravity of the core component is provided at the tip of the convex part, It is preferable that the ratio GN/GM of the distance GM from the center of gravity G of the shim component to the bottom M of the groove and the distance GN from the center of gravity G of the shim component to the tip N of the convex part is 1.1 to 1.5.

The distance GM from the center of gravity G of the seam component to the bottom M of the groove as used in the present invention is, for example, an intersection point of two arbitrary straight lines that halve the area of the seam component as shown in Fig. 5(a). The distance between the center of gravity G1 of the seam component and the groove bottom M1, which is the closest point to the center of gravity G1 of the seam component on the groove surface, is calculated. In this case, when two or more shim components exist, the largest value obtained from each shim component is adopted. The simple number average of the results of this operation for 10 randomly extracted fibers was rounded up to the first place of the decimal point, and the distance from the center of gravity G of the seam component to the bottom M of the groove was GM (μm).

In the present invention, the distance GN from the center of gravity G of the seam component to the tip N of the convex portion is, for example, as shown in Fig. 5(a), the center of gravity G1 of the seam component and the seam component on the groove surface. To calculate the distance of the tip N1 of the convex part, which is the farthest point to the center of gravity G1 of In this case, when two or more shim components exist, the largest value obtained from each shim component is adopted. A simple number average of the results of this operation for 10 randomly extracted fibers was rounded up to the first decimal place, and the distance GN (μm) from the center of gravity G of the seam component to the tip N of the convex part was taken.

In addition, for the distance GM from the center of gravity G of the seam component to the bottom M of the groove and the distance GN from the center of gravity G of the seam component to the tip N of the convex part, a simple number average of the ratio (GN/GM) is calculated, The value rounded off from the 3rd decimal point was made into GN/GM. At this time, GN/GM=1.0 was set as the case where a groove|channel did not exist at the tip of a convex part in a seam component.

In the present invention, by having a groove with a depth at which GN/GM is 1.1 or more in the direction of the center of gravity of the core component at the tip of the convex part after the dissolution of the super component, the surface of the groove is in contact with the skin by a point to improve frictional force. This is preferable because it can emphasize the dry feeling. In addition, when GN/GM is set to a groove depth of 1.3 or more, light is diffused in addition to a dry feeling, and not only a milder gloss but also white blur caused by specular reflection of light is suppressed, and color development when dyed is improved. It is mentioned as a more preferable range. However, the practical upper limit of GN/GM is 1.5 because, when the groove depth is increased, the frictional force becomes excessively high, and abrasion resistance such as fibrillation may deteriorate.

In the core sheath composite fiber of the present invention from the viewpoint of pursuing natural silk texture by reproducing in more detail the voids between fibers unique to natural silk, the core component is divided into two or more by the sheath component, and each of the divided core components is It is preferable to have the above-mentioned multi-leaf shape.

At the point of raw and dead material extracted from the cocoon, which is the basis of natural silk, fibroin (FIG. 1a), which consists of two triangular cross-sections, a poorly eluting component, is covered with sericin (FIG. 1b), which consists of a dissolving component. consists of In other words, the voids between the divided and adjacent fibers are always controlled only by the ratio of sericin elution, regardless of the arrangement of the single fibers in the multifilament, and this is a microscopic size of less than 5 μm between each single single fiber unique to natural silk. It can be understood that the state in which the interfiber voids exist stably is created, and in the core-sheath composite fiber of the present invention, the core component is divided into two or more by the sheath component, and the divided core component each has a multi-leaf shape. It is preferable to have The number of divisions is not particularly limited as long as it is two or more. For example, it may be divided into six seam components as shown in Fig. 4(c). , the upper limit of the actual number of divisions becomes 10 because precise control of the cross section becomes difficult.

In the present invention, in order to make the voids between fibers more coarse, polymers having different melting points are arranged adjacent to each other in the cross section of the fibers, and the core sheath composite fiber is crimped from the difference in shrinkage during heat treatment resulting from the difference in melting points, or It is preferable to express the difference in yarn length after eluting the sheath component of the core sheath composite fiber. If the voids between fibers can be coarsened, not only high-quality gloss and high color development can be obtained by increasing diffuse reflection of light, but also lightness due to an increase in porosity and a decrease in apparent density can be further emphasized.

That is, in the core-sheath composite fiber of the present invention, in the core component divided by the sheath component, the adjacent core component 1 (for example, c1 in FIGS. 4(a), (b), (c)) and the core component 2 It is preferable that (for example, c2 in FIGS. 4(a), (b), (c)) consists of polymers with different melting|fusing points.

In the present invention, polymers with different melting points are polyester, polyethylene, polypropylene, polystyrene, polyamide, polycarbonate, polymethyl methacrylate, polyphenylene sulfide, etc. that can be melt molded. It refers to a combination of polymers with different melting points of 10°C or more among the polymer group and its copolymers. In addition, in the core-sheath composite fiber of the present invention, the purpose of the core-sheath composite fiber is to provide a crimped form to the core-sheath composite fiber by using the shrinkage difference of the core component, or to express a difference in yarn length after eluting the sheath component of the core-sheath composite fiber. As a combination of polymers with different melting points, it is preferable to use core component 1 as a high shrinkage low melting point polymer and core component 2 as a low shrinkage high melting point polymer. For example, as polyester, copolymerized polyethylene terephthalate/polyethylene terephthalate, polybutylene terephthalate/polyethylene terephthalate, polytrimethylene terephthalate/polyethylene terephthalate, thermoplastic polyurethane/polyethylene terephthalate, polyester elastomer/ Polyethylene terephthalate, polyester elastomer/polybutylene terephthalate, polyamide based nylon 66/nylon 610, nylon 6-nylon 66 copolymer/nylon 6 or 610, PEG copolymerized nylon 6/nylon 6 or 610, thermoplastic Polyurethane/nylon 6 or 610, various combinations of ethylene-propylene rubber finely dispersed polypropylene/polypropylene, propylene-α-olefin copolymer/polypropylene, etc. as the polyolefin type, but the core sheath of the present invention In the composite fiber, from the viewpoint of not only being able to achieve a bending rigidity close to that of natural silk, but also obtaining good color development when dyed, a particularly preferable range for the core component to be divided is a polyester-based combination. Moreover, as a copolymerization component in copolymerization polyethylene terephthalate, succinic acid, adipic acid, azelaic acid, sebacic acid, 1, 4- cyclohexanedicarboxylic acid, maleic acid, phthalic acid, isophthalic acid, 5-sodium alcohol, for example. Although poisophthalic acid etc. are mentioned, It is preferable to make isophthalic acid into 5 mol% to 15 mol% copolymerized polyethylene terephthalate from a viewpoint of being able to maximize the shrinkage difference with polyethylene terephthalate.

In the core sheath composite fiber of the present invention, the area ratio of the core component 1, which is a low-melting polymer, and the core component 2, which is a high-melting point polymer, is in the range of 70%/30% to 30%/70% of core component 1/core component 2 it is preferable Within this range, when the low-melting-point polymer is highly contracted by heat treatment, the core-sheath composite fiber is crimped or the sheath component of the core-sheath conjugate After elution, the difference in yarn length can be sufficiently expressed, and more coarse interfiber voids can be obtained.

The core sheath composite fiber of the present invention is to obtain a multifilament composed of a core component by eluting the sheath component after forming a fiber structure in various sheet shapes such as a woven knitted fabric, a nonwoven fabric, or a papermaking paper. In the multifilament, it is possible to obtain the texture of natural silk, such as a high-quality gloss and dry feel, and a light, flexible and repulsive feel expressed from the unique fiber cross-sectional shape and voids between fibers.

In order to maximize the texture of natural silk, such as the above-mentioned high-quality luster and light, flexible and repulsive texture, fine fibers of less than 5 μm are interspersed among the fibers of natural silk among multifilaments. The point is to form a pore structure in which interstitial voids and coarse interfiber voids of 10 μm or more are uniformly mixed. Therefore, in the multifilament of the present invention, it is important to have a pore structure in which the average inter-fiber void distance is 5 to 30 µm, and the proportion of which the inter-fiber void distance is less than 5 µm is 10 to 50%.

In the present invention, the inter-fiber void distance refers to a cross section of the fabric that is perpendicular to the longitudinal direction of the fabric and perpendicular to the fiber axis direction of the multifilaments in a fabric made of multifilaments using a scanning electron microscope (SEM) to measure 10 or more fibers. The image is taken at a magnification that can be observed. For each photographed image, draw a perfect circle in which 10 fibers enter as shown in FIG. 8(b), select one arbitrary fiber out of 10 fibers existing inside the perfect circle, and weigh the fiber and neighboring fibers The intersection of the straight line connecting the centers and the surface of each fiber was obtained, and the distance between the intersections was measured to the first decimal place in μm. In addition, the value obtained by rounding off the first decimal place of the obtained value was defined as the interfiber void distance (µm). As used herein, "neighboring" means that there is no other fiber on a straight line connecting the center of gravity and the center of gravity of two arbitrary fibers. For 10 fibers existing inside the perfect circle, this operation is performed for all neighboring fibers as shown in Fig. 8(b), a simple number average of the results is obtained, and the value rounded to the first place of the decimal point is the average inter-fiber void. It was set as the distance (micrometer). In addition, the ratio at which the inter-fiber void distance becomes less than 5 µm was also calculated.

The longer the average inter-fiber void distance, the more space is created at the binding point of the woven and knitted fabric to allow the fixed fibers to move. In addition, when the average inter-fiber void distance is 10 µm or more, bulkiness is expressed, and when it is made into a fabric, the apparent density decreases and the lightness improvement effect is also added. It can be mentioned as a range. From this point of view, the lightness and flexibility are improved, while the effect of suppressing the decrease in bending stiffness in the interfiber voids of less than 5 μm uniformly mixed in the multifilaments becomes small and the feeling of repulsion tends to decrease. 30 mu m becomes a practical upper limit.

In addition to the above, it is possible to suppress a decrease in bending rigidity due to an increase in the average interstitial distance, and in order to maintain a sense of repulsion, it is necessary to set the ratio of the interfiber void distance to less than 5 μm to 10% or more. In addition, when the ratio of the inter-fiber void distance of less than 5 μm to 20% or more, the trade-off relationship between lightness and flexibility and repulsion is resolved, and a light, flexible and repulsive feel can be expressed in a balanced way, so it is considered a preferable range. can From this point of view, if the ratio of the inter-fiber void distance less than 5 μm is increased, the feeling of repulsion is improved, while lightness or flexibility tends to decrease.

In the multifilament of the present invention, it is preferable to have a pore structure having a porosity of 30 to 80%.

Here, the porosity in the present invention refers to a fabric made of multifilaments, in which 10 or more fibers are observed with a scanning electron microscope (SEM) in a cross section of the fabric perpendicular to the longitudinal direction of the fabric and perpendicular to the fiber axis direction of the multifilaments. Take pictures at a magnification that can be done. For each photographed image, a perfect circle containing 10 fibers was drawn as shown in FIG. 8(b), and a value obtained by subtracting the total cross-sectional area of 10 fibers existing inside the perfect circle from the cross-sectional area of the perfect circle was calculated. At this time, if 1/2 or more of the fibers were contained inside the perfect circle, it was counted as one fiber, and the cross-sectional area was measured to the first decimal place in µm ² . In addition, the value obtained by dividing the obtained value by the cross-sectional area of the perfect circle was calculated, and the value obtained by rounding off the first decimal place after multiplying by 100 was made into the porosity (%).

If the multifilament has a pore structure having a porosity of 30% or more, it is preferable because there is enough space for the fibers fixed at the binding point of the woven/knitted fabric to move, and the effect of improving the flexibility is obtained.

In addition, when the porosity is 50% or more, when the porosity is 50% or more, it has a high porosity, and when it is made into a fabric, the apparent density decreases and the lightness improvement effect is also added. can be heard as From this point of view, the higher the average inter-fiber void distance and porosity, the higher the lightness and flexibility, while the effect of suppressing the decrease in bending stiffness in the inter-fiber voids of less than 5 μm uniformly mixed in multifilaments is reduced, and the feeling of repulsion is reduced. Since it tends to have a pore structure with a porosity of 80%, it becomes a practical upper limit.

In the multifilament of the present invention, it is preferable that two or more kinds of crimpable fibers composed of polymers having different melting points are uniformly mixed. Here, the crimpable fiber referred to in the present invention refers to a fiber having a twisted crimp shape as shown in FIG. 7 .

In addition, in the present invention, "the crimpable fibers are uniformly mixed" means that in any crimpable fiber X in the multifilament, as shown in Fig. 8(a), all crimping properties adjacent to the crimping fiber X are It means that at least one crimpable fiber Y composed of a different polymer from the crimpable fiber X among the fibers is present. In addition, "neighbor" as used in the present invention means that no other crimping fibers exist on a straight line connecting the center of gravity of the crimpable fiber X and the center of gravity of any crimping fiber. As a method of obtaining the pore structure of the multifilament of the present invention, a method of eluting the sheath component after bundling a plurality of core sheath composite fibers as shown in Fig. 2 (a) or Fig. 5 (a) or Fig. 4 (a) (b) (c) ), there are various methods, such as a method of tying a plurality of core-sheath composite fibers with adjacently arranged core components made of polymers with different melting points, such as a method of eluting and dividing the sheath component, and then expressing the difference in yarn length by heat treatment, From the viewpoint of more uniformly mixing fine interfiber voids of less than 5 μm and coarse interfiber voids of 10 μm or more in the multifilament, the fiber cross section as shown in FIGS. A winding composed of different polymers by tying a plurality of core-sheath composite fibers composed of polymers having different melting points of core components c1 and c2 divided into two, heat treatment to develop a crimped form, and then eluting the sheath component and dividing for each polymer It is preferable to use a method in which the veneering fibers are uniformly mixed.

When the above method is used, a crimped form is expressed by heat-treating the core-sheath composite fiber, and coarse interfiber voids of 10 µm or more can be formed. In addition, since the sheath component exists between the core components, after the sheath component is eluted, it is possible to more stably form interfiber voids of less than 5 μm between the crimped fibers made of polymers with different melting points adjacent to each other. Therefore, it is possible to more uniformly mix fine inter-fiber voids of less than 5 μm and coarse inter-fiber voids of 10 μm or more in the multifilament. That is, in the multifilament of the present invention, it is preferable that two or more kinds of crimpable fibers composed of polymers having different melting points are uniformly mixed, and thereby, it is possible to avoid the specific fiber cross-sectional shape and void structure. It is possible to further enhance the texture of natural silk, such as the expressed high-quality luster, dry feel, and light, flexible and repulsive feel.

In the multifilament of the present invention, it is preferable that the crimpable fibers have a number of crimps of 5 yarns/cm or more.

When it is set in such a range, the exclusion volume effect between fibers can fully be exhibited and it becomes possible to form coarse interfiber voids of several tens of micrometers. In addition, when it is 10 acids/cm or more, the exclusion volume effect between fibers becomes higher, so that the size of the voids between fibers can be made coarser, and a light and flexible feel close to natural silk can be expressed in a more suitable range. can be heard as On the other hand, if the number of crimps is increased, the steric hindrance effect due to the crimp shape exceeds the exclusion volume effect, entanglement between fibers may occur and flexibility may be impaired. becomes

In the multifilament of the present invention, it is preferable that the difference in yarn length between two or more kinds of crimpable fibers composed of different polymers is 3% or more. When the difference in yarn length is 3% or more, the number of crimps of the crimpable fibers composed of polymers having different melting points in which the crimped form is expressed can be set to 10 acids/cm or more. However, if the yarn length difference becomes too large, the number of crimping increases accordingly, and the steric hindrance effect due to the crimp shape exceeds the excluded volume effect, entanglement between fibers occurs, and flexibility may be impaired. The upper limit is 20%.

In the multifilament of the present invention, it is preferable that the crimpable fiber is composed of a homopolymer. When the crimpable fiber is composed of a homopolymer, the core-sheath composite fiber composed of a polymer with a different melting point adjacent to it expresses a crimped form by heat treatment, so that the crimping phase is aligned in the neighboring crimping fiber, and between fine fibers of less than 5㎛ It becomes possible to form voids. On the other hand, when composed of two or more different polymers, the center of gravity of the polymer on the cross-section is different depending on the composite cross-section. Since the crimp phase is not aligned, it becomes difficult to stably form fine interfiber voids of less than 5 μm.

In the fiber constituting the multifilament of the present invention, in the fiber cross section, it is preferable to have a multilobed shape having three or more convex portions.

In the cross section of the fiber, if it is made into a multi-leaf shape having three or more convex parts, the effect of amplifying the reflection of light is obtained by forming concavo-convex parts on the fiber surface, and complex reflection of light due to the presence of voids between fibers of large and small sizes as described above is also harmonized with natural silk. It has the same high luminance and can express a luxurious luster called a mild luster. Moreover, a dry feeling can also be obtained by the improvement of frictional force by the formation of unevenness|corrugation on the fiber surface. From this point of view, as the number of convex portions increases, the gloss effect and dry feeling increase. However, when the number of uneven portions increases, the spacing between the uneven portions becomes dense, and the effect gradually approximates a round cross-section. The practical upper limit of the convex portions of the fiber is six.

In the fiber constituting the multifilament of the present invention, the relationship between the inscribed circle diameter R _C (the diameter of C in Fig. 9 (a)) and the circumscribed circle diameter R _D (the diameter of D in Fig. 9 (a)) is 1.5≤R _D / It is preferred that R _C ≤ 2.0. However, R _D /R _C referred to herein indicates the degree of irregularity of the fiber. In such a range, it is preferable from the viewpoint of quality control because the light reflected and amplified by the concave-convex portion of the multi-leaf shape is uniformly reflected without flashing.

The fiber constituting the multifilament of the present invention has a groove at the tip of the convex portion in the fiber cross section from the viewpoint of emphasizing the dry feeling, and the distance MN from the bottom of the groove M to the tip N of the convex portion is It is preferable that the ratio (MN/D) of the fiber diameter D is 0.04 to 0.20.

The ratio (MN/D) of the distance MN from the bottom of the groove M to the tip N of the convex part N as used in the present invention and the fiber diameter D (MN/D) is obtained by embedding the multifilaments of the present invention with an embedding agent such as an epoxy resin, in a direction perpendicular to the fiber axis. The fiber cross-section can be obtained by taking an image with a scanning electron microscope (SEM) at a magnification that allows observation of 10 or more fibers. In the fibers randomly extracted from each photographed image within the same image, for example, as shown in Fig. 9, the weight of the intersection of two arbitrary straight lines whose cross-sectional area in the fiber cross-section of the crimped fiber is halved. From the center G, the distance MN between the groove bottom M, which is the closest point to the groove surface, and the convex portion tip N, which is the furthest point, was calculated.

Moreover, the diameter of the said fiber was measured to the 1st decimal place in micrometer unit. At this time, if the fiber cross-section in the direction perpendicular to the fiber axis is not a perfect circle, the area was measured and a value obtained in circle conversion was adopted as the fiber diameter.

For the obtained distance MN from the bottom of the groove M to the tip N of the convex portion and the fiber diameter D, the ratio (MN/D) was calculated to the fourth decimal place, and this operation was performed for 10 randomly extracted fibers. MN/D was obtained as the simple number average of , and rounded up to the third decimal place. In this case, MN/D=0 was set when the crimpable fiber did not have a groove at the tip of the convex portion.

In the fiber constituting the multifilament of the present invention, by having a groove having a depth such that the MN/D is 0.04 or more, the surface of the groove is in contact with the skin at a point, thereby improving the frictional force, thereby emphasizing the dry feeling. it is preferable to have In addition, when the MN/D is 0.10 or more, when the groove depth is set to 0.10 or more, light is diffused in addition to a dry feeling, and not only a milder gloss but also white blur due to specular reflection of light is suppressed, so that color development when dyed is improved. It can be mentioned as a more preferable range. However, the practical upper limit of MN/D is 0.20 because, when the groove depth is increased, the frictional force becomes excessively high, and abrasion resistance such as fibrillation may deteriorate.

In the fiber constituting the multifilament of the present invention, it is preferable that the fiber diameter be 15 µm or less from the viewpoint of making the feel more flexible. In addition, by setting the fiber diameter to 12 μm or less, the single yarn fineness of natural silk, about 10 μm, can be obtained, and a texture closer to natural silk can be obtained. becomes the range. However, if the fiber diameter is too thin, the bending recovery property is lowered, and the sense of repulsion, which is one of the textures of natural silk, is impaired, and the color development property is also reduced.

In the core-sheath composite fiber and multifilament of the present invention, a unique pore structure in which fine inter-fiber voids of less than 5 μm and coarse inter-fiber voids of several tens of μm are uniformly mixed between each fiber exhibited by natural silk is formed can do. Therefore, if the core-sheath composite fiber or multifilament of the present invention is used as a fiber product comprising at least one part, various textures unique to natural silk can be reproduced. The unique ease of handling combines from general medical care such as jackets, skirts, pants, and underwear to sports medicine, medical materials, interior products such as carpets, sofas and curtains, vehicle interiors such as car seats, cosmetics, cosmetic masks, and wiping cloths. It can be suitably used for a wide range of textile products, such as daily use, such as health care products.

An example of the manufacturing method of the core-sheath composite fiber and multifilaments of this invention is described in detail below.

As a method for spinning the core sheath composite fiber of the present invention composed of two or more polymers, a melt spinning method for the purpose of producing long fibers, a solution spinning method such as wet and dry methods, a melt blow method suitable for obtaining a sheet-shaped fiber structure, and Although it is also possible to manufacture by a spunbonding method etc., the melt spinning method is suitable from a viewpoint of improving productivity. In addition, in the melt spinning method, it can be produced by using a composite spinneret to be described later, and the spinning temperature at that time is set as a temperature at which a high melting point or a high viscosity polymer mainly exhibits fluidity among the polymer species used. Although the temperature at which this fluidity is exhibited also varies depending on the molecular weight, it can be stably produced by setting it between the melting point of the polymer and the melting point + 60°C.

The spinning speed may be set to about 500 to 6000 m/min, and may be changed according to the physical properties of the polymer or the purpose of use of the fiber. In particular, from the viewpoint of improving the mechanical properties by setting it to high orientation, it is preferably set at 500 to 4000 m/min, and then stretching, since uniaxial orientation of the fiber can be promoted. At the time of stretching, it is preferable to set the preheating temperature appropriately by targeting a temperature that can be softened, such as the glass transition temperature of the polymer. As the upper limit of the preheating temperature, it is preferable to set it as a temperature at which the yarn path is not disturbed due to the spontaneous elongation of the fibers during the preheating process. For example, in the case of PET having a glass transition temperature of around 70°C, the preheating temperature is usually set to about 80 to 95°C.

Moreover, if the discharge amount per single hole in the spinneret in the core-sheath composite fiber of this invention is 0.1-10 g/min/hole or so, it becomes possible to manufacture stably. The discharged polymers are cooled and solidified, then an emulsion is applied, and the discharged polymer is taken up by a roller with a specified peripheral speed. Thereafter, it is drawn with a heating roller to obtain a desired core-sheath composite fiber.

Further, in the core-sheath composite fiber of the present invention composed of two or more types of polymers, when the melt viscosity ratio of the polymer to be used is less than 5.0 and the difference in solubility parameter value is less than 2.0, a composite polymer can be stably formed and a good composite It is preferable because a fiber of a cross-section can be obtained.

It is preferable to use the composite spinneret described in Unexamined-Japanese-Patent No. 2011-208313 as a composite spinneret used when manufacturing the core sheath composite fiber of this invention which consists of two or more types of polymers. The composite spinneret shown in Fig. 12 of the present application is mounted in a spinning pack in a state in which three types of members are stacked from above: a metering plate 1, a distribution plate 2, and a discharging plate 3, and provided for spinning. Incidentally, Fig. 12 is an example in which three types of polymers called A polymer, B polymer, and C polymer are used. In the conventional composite spinneret, it is difficult to complex three or more types of polymers, and it is preferable to use a complex spinneret using a microchannel as illustrated in FIG. 12 .

In the nozzle illustrated in FIG. 12 , the metering plate 1 measures and flows in the amount of polymer per each discharge hole and each distribution hole, and the composite cross-section in the cross-section of the single fiber and its cross-sectional shape by the distribution plate 2 and plays a role of compressing and discharging the composite polymers formed in the distribution plate 2 by the discharge plate 3 .

In order to avoid confusing the description of the compound nozzle, although not shown, for the member laminated above the metering plate 1, a member having a flow path aligned with the spinning machine and the spinning pack may be used. By designing the measuring plate 1 according to the existing flow path member, the existing spinning pack and its members can be used as it is. For this reason, it is not necessary to privatize the thrower, especially for the detention. Also, in practice, it is sufficient to stack a plurality of flow path plates between the flow path and the metering plate or between the metering plate 1 and the distribution plate 2 . The purpose of this is to form a flow path through which the polymer is efficiently transported in the cross-sectional direction of the spinneret and the short fibers, and to be introduced into the distribution plate 2 . The composite polymers discharged from the discharge plate 3 are cooled and solidified according to the above-mentioned manufacturing method, then an oil agent is applied, and the composite polymer is taken up by a roller having a prescribed peripheral speed. Thereafter, drawing is performed with a heating roller to obtain a desired core-sheath composite fiber.

In the case of manufacturing a multifilament composed of a core component by removing the sheath component from the core sheath composite fiber of the present invention, it is necessary to elute the sheath component to obtain a fiber composed of the core component. It is good to remove the sheath component by immersing the core sheath composite fiber. When the dissolving component is copolymerized polyethylene terephthalate or polylactic acid in which 5-sodium sulfoisophthalic acid or polyethylene glycol is copolymerized, an aqueous alkali solution such as an aqueous sodium hydroxide solution can be used. At this time, when the aqueous alkali solution is heated to 50°C or higher, the hydrolysis can be accelerated, so it is preferable. In addition, the use of a fluid dyeing machine or the like is preferable from an industrial point of view because a large amount of processing can be performed at once.

Example

Hereinafter, the core-sheath composite fiber and multi-filament of the present invention will be described in detail with reference to Examples.

The following evaluation was performed about an Example and a comparative example.

A. Melt Viscosity of Polymers

The chip-shaped polymer was made into a moisture content of 200 ppm or less with a vacuum dryer, and the melt viscosity was measured by changing the strain rate stepwise by using a capillograph made by Toyo Seiki. In addition, the measurement temperature was carried out similarly to the radiation temperature, the time from introducing the sample to the heating furnace under a nitrogen atmosphere to the start of the measurement was 5 minutes, and the value of the shear rate 1216s ^-1 was evaluated as the melt viscosity of the polymer.

B. Melting Point of Polymer

Weigh about 5 mg of the chip-shaped polymer with a moisture content of 200 ppm or less with a vacuum dryer, and use a differential scanning calorimeter (DSC) Q2000 type manufactured by TA Instruments to increase the temperature from 0°C to 300°C at a temperature increase rate of 16°C/min. , the DSC measurement was performed by holding at 300°C for 5 minutes. The melting point was calculated from the melting peak observed during the temperature increase process. The measurement was performed 3 times with respect to 1 sample, and the average value was made into melting|fusing point. In addition, when two or more melting|fusing peaks were observed, the melting|fusing peak top on the side of the highest temperature was made into melting|fusing point.

C. Fineness

The weight of the multifilament of 100 m was measured, and the value which multiplied the value 100 times was computed. This operation was repeated 10 times, and the value obtained by rounding off the second decimal place of the average value was defined as the fineness (dtex) of the multifilament.

D. Section parameters (R _B /R _A )

The core sheath composite fiber was embedded with an embedding agent such as an epoxy resin, and the cross section of the fiber in the direction perpendicular to the fiber axis was taken at a magnification capable of observing 10 or more fibers with a scanning electron microscope (SEM) manufactured by HITACHI, and an image was taken. By analyzing the obtained image using WinROOF manufactured by Shoji Mitani of computer software, the diameter of the circumscribed circle of the fiber RB (for example, the diameter of _B in Fig. 4(a)) and the diameter of the inscribed circle of the fiber R _A (for example, the diameter of Fig. 4(a)) It calculated about RB /R _A which is the ratio of (diameter of _A in (a)). However, in the present invention, the measurement was performed three times for one filament, and the simple number average of the results obtained for 10 filaments was obtained, and the value rounded up to the third decimal place was defined as _{RB /RA A .}

E. Section parameters (Smin/D, Smax/Smin)

The core sheath composite fiber was embedded with an embedding agent such as an epoxy resin, and the fiber cross-section in the direction perpendicular to the fiber axis was taken at a magnification at which 10 or more fibers could be observed with a transmission electron microscope (TEM). At this time, if metal dyeing is performed, the contrast of the junction part of the composite component can be made clear by using the dyeing difference between the polymers. In the photographed image, the ratio Smin/D of the minimum thickness Smin of the sheath component to the fiber diameter D and the ratio Smax/Smin of the maximum thickness Smax of the sheath component and the minimum thickness Smin of the sheath component were calculated.

However, in the present invention, the diameter of fibers randomly extracted within the same image from each photographed image is measured to the first decimal place in μm, and this operation is a simple number average of the results of 10 randomly extracted fibers. The value obtained by rounding off the first decimal place was taken as the fiber diameter D (μm). Here, when the fiber cross-section in the direction perpendicular to the fiber axis is not a perfect circle, a value obtained by measuring the area and converting to a circle is employed.

In addition, the minimum thickness Smin of the sheath component in the present invention is, for example, as shown in Figs. Draw a straight line from the center of gravity G1 of the existing seam component 1 toward the surface of any fiber, and measure the distance S1-F between the outer periphery of seam component 1 and the straight line intersection S1 and the fiber surface and the straight line intersection point F to the first decimal place. It calculates the value and calculates the minimum value among the obtained values. A simple number average of the results of this operation for 10 randomly extracted fibers was rounded up to the first decimal place, and the minimum thickness Smin (µm) of the second component was taken. Here, for example, as shown in Figs. 4(a) and 5(b), on a straight line drawn from the center of gravity G1 of the seam component 1 toward an arbitrary fiber surface, a seam different from the seam component 1 taking the center of gravity When component 2 exists, the measured distance S1-S2 of the intersection S1 between the outer periphery of the seam component 1 and the straight line and the intersection S2 closest to S1 among the intersections of the outer periphery and the straight line of the seam component 2 was adopted.

With respect to the obtained fiber diameter D and the minimum thickness Smin of the sheath component, a simple number average of the ratio (Smin/D) was calculated, and the value rounded off to the third decimal place was defined as Smin/D.

In addition, the minimum thickness Smax of the sheath component in the present invention is, for example, as shown in Figs. Draw a straight line from the center of gravity G1 of the existing seam component 1 toward the surface of any fiber, and measure the distance S1-F between the outer periphery of seam component 1 and the straight line intersection S1 and the fiber surface and the straight line intersection point F to the first decimal place. It is to calculate the value, and to calculate the maximum value among the obtained values. A simple number average of the results of this operation performed on 10 randomly extracted fibers was rounded up to the first decimal place, and the minimum thickness Smax (µm) of the second component was taken. Here, for example, as shown in Figs. 4(a) and 5(b), on a straight line drawn from the center of gravity G1 of the seam component 1 toward an arbitrary fiber surface, a seam different from the seam component 1 taking the center of gravity When component 2 exists, the measured distance S1-S2 of the intersection S1 between the outer periphery of the seam component 1 and the straight line and the intersection S2 closest to S1 among the intersections of the outer periphery and the straight line of the seam component 2 was adopted.

For the obtained maximum thickness Smax of the second component and the minimum thickness Smin of the second component, a simple number average of the ratio (Smax/Smin) was calculated, and the value rounded off to the second decimal place was defined as Smax/Smin.

F. Section parameters (GN/GM)

In the case where the core-sheath composite fiber observed in E. has a groove in the direction of the center of gravity of the core component at the tip of the convex part in the multi-leaf-shaped core component, the distance from the center of gravity G of the core component to the bottom M of the groove GM And the ratio GN/GM of the distance GN from the center of gravity G of the shim component to the tip N of the convex part was calculated. At this time, when a groove|channel does not exist at the tip of a convex part in a seam component, it was set as GN/GM=1.0.

The distance GM from the center of gravity G of the seam component to the bottom M of the groove in the present invention is, for example, the intersection point of two arbitrary straight lines that halve the area of the seam component as shown in Fig. 5(a). The distance between the center of gravity G1 of the in-shim component and the groove bottom M1, which is the closest point to the center of gravity G1 of the seam component on the groove surface, is calculated. In this case, when two or more shim components exist, the largest value obtained from each shim component is adopted. The simple number average of the results of this operation for 10 randomly extracted fibers was rounded up to the first place of the decimal point, and the distance from the center of gravity G of the seam component to the bottom M of the groove was GM (μm).

In addition, the distance GN from the center of gravity G of the seam component in this invention to the front-end|tip N of a convex part is, as shown, for example to Fig.5 (a), the center of gravity G1 of a seam component, and the seam in the groove|channel surface. This is to calculate the distance of the tip N1 of the convex part, which is the point furthest from the center of gravity G1 of the component. At this time, when two or more shim components exist, the largest value obtained from each shim component is employed. A simple number average of the results of this operation for 10 randomly extracted fibers was rounded up to the first decimal place, and the distance GN (μm) from the center of gravity G of the seam component to the tip N of the convex part was taken.

For the distance GN from the center of gravity G of the obtained seam component to the bottom M of the groove and the distance GN from the center of gravity G of the seam component to the tip N of the convex part, calculate a simple number average of the ratio (GN/GM) to remove the decimal point. 3 The value rounded off above was set to GN/GM.

G. Mixed state of fibers in multifilaments

In a fabric made of multifilaments, the cross section of the fabric perpendicular to the length direction of the fabric and perpendicular to the fiber axis direction of the multifilaments is magnified so that 10 or more fibers can be observed with a scanning electron microscope (SEM) manufactured by HITACHI. Take an image. By analyzing the photographed image using WinROOF manufactured by Shoji Mitani of computer software, as shown in FIG. It was evaluated how many fibers Y composed of a polymer different from the fiber X among all the fibers in a state in which other fibers do not exist on a straight line. In this evaluation, a simple number average of the results of 10 fibers randomly extracted from one multifilament was obtained, and the mixed state was judged in two stages based on the following criteria, respectively, from the value rounded off from the first decimal point.

A: uniformly mixed (one or more fibers Y composed of fibers X and other polymers)

C: skewed and mixed (less than one fiber Y composed of fiber X and another polymer)

H. Number of crimps (mountain/cm)

In a fabric made of multifilaments, the multifilaments are pulled out from the fabric so as not to be plastically deformed, one end of the multifilaments is fixed, and a load of 1 mg/dtex is applied to the other end. Marking was performed at an arbitrary location where the distance between the two points in the direction of the fiber axis of the filament was 1 cm. Thereafter, the fibers are divided from the multifilaments so as not to be plastically deformed, and the pre-made marks are adjusted to be 1 cm from the original size and fixed on a slide glass. An image was taken at a magnification that could observe a 1 cm marking with a scope. The image|photographed image WHEREIN: The number of crimps between markings was calculated|required. A simple number average of the results of this operation performed for ten fibers composed of the same polymer was obtained, and the value rounded off from the first decimal point was taken as the number of crimped divisions (mountain/cm). If fibers made of different polymers were mixed, the number of crimps was calculated for the fibers made of each polymer, and the number of crimps of the fibers made of the polymer having the largest number of crimps was adopted.

I. Thread Length Difference

In a fabric made of multifilaments, the multifilaments are pulled out from the fabric so as not to be plastically deformed, one end of the multifilaments is fixed, and a load of 1 mg/dtex is applied to the other end. Marking was performed at an arbitrary location where the distance between the two points in the direction of the fiber axis of the filament was 1 cm. Thereafter, the fibers were divided from the multifilaments so as not to be plastically deformed, adjusted so that the distance between the markings made in advance was 1 cm, and fixed on a slide glass, and this sample was fixed by 1 cm with a VHX-2000 digital microscope manufactured by Keyence Corporation. The image was taken at a magnification at which the marking of The yarn length between markings was measured by analyzing the obtained image using WinROOF manufactured by Shoji Mitani of computer software. In the case of fibers made of different polymers, a simple number average of the results of each of 10 fibers is obtained, and from the results obtained, (maximum yarn length - minimum yarn length)/(minimum yarn length) x100 was calculated and the value rounded off from the 1st decimal point was made into the real length difference (%).

J. Inter-fiber void distance

In a fabric made of multifilaments, the cross section of the fabric perpendicular to the longitudinal direction of the fabric and perpendicular to the fiber axis direction of the multifilaments is magnified so that 10 or more fibers can be observed with a scanning electron microscope (SEM) manufactured by HITACHI. take a picture By analyzing the captured image using WinROOF manufactured by Shoji Mitani, a computer software, a perfect circle containing 10 fibers is drawn as shown in Fig. 8(b), and one arbitrary fiber is selected from the 10 fibers existing inside the circle. Then, the intersection of the straight line connecting the center of gravity of the fiber and the neighboring fibers and the surface of each fiber was obtained, and the distance between the intersections was measured to the first decimal place in μm. In addition, the value obtained by rounding off the first decimal place of the obtained value was defined as the interfiber void distance (µm). As used herein, "neighboring" means that there is no other fiber on a straight line connecting the center of gravity and the center of gravity of two arbitrary fibers. This operation is performed on all neighboring fibers as shown in Fig. 8(b) for 10 fibers existing inside the perfect circle, and the result obtained by calculating the simple number average is rounded up to the first decimal place and the average inter-fiber void distance ( μm). In addition, the ratio at which the inter-fiber void distance becomes less than 5 µm was also calculated.

K. Porosity

In a fabric made of multifilaments, the cross section of the fabric perpendicular to the longitudinal direction of the fabric and perpendicular to the fiber axis direction of the multifilaments is magnified so that 10 or more fibers can be observed with a scanning electron microscope (SEM) manufactured by HITACHI. take a picture By analyzing the captured image using WinROOF manufactured by Shoji Mitani, computer software, a perfect circle containing 10 fibers is drawn as shown in Fig. 8(b), and the total cross-sectional area of 10 fibers existing inside the perfect circle is subtracted from the cross-sectional area of the perfect circle. was calculated. At this time, if 1/2 or more of the fibers were contained inside the perfect circle, it was counted as one fiber, and the cross-sectional area was measured to the first decimal place in µm ² . In addition, the value obtained by dividing the obtained value by the cross-sectional area of the perfect circle was calculated, and the value obtained by rounding off the first decimal place after multiplying by 100 was made into the porosity (%).

L. Fiber diameter of heterogeneous cross-section fibers

Using the image taken in item K., the diameter of randomly extracted fibers within the same image was measured to the first decimal place in μm, and this operation was performed for 10 randomly extracted fibers. The value obtained by rounding off the first decimal place was taken as the fiber diameter D (μm). Here, when the fiber cross-section in the direction perpendicular to the fiber axis is not a perfect circle, a value obtained by measuring the area and converting to a circle is employed.

M. Section parameters (R _D /R _C )

By analyzing the image taken in item K. using WinROOF manufactured by Shoji Mitani, a computer software, the circumscribed circle diameter R _D of the fiber (for example, the diameter of C in Fig. 9(a)) and the inscribed circle diameter R _C of the fiber (example For example, it was calculated with respect to R _D /R _C , which is the ratio of the diameter of C in FIG. 9( a ). However, in the present invention, measurements were performed three times for 1 filament, and the simple number average of the results obtained for 10 filaments was obtained, and the value rounded up to the second decimal place was defined as R _D /R _C .

N. Section parameters (MN/D)

When the fiber observed in item K. has a groove at the tip of the convex portion, the distance MN from the bottom of the groove M to the tip N of the convex portion and the ratio MN/D of the fiber diameter D were calculated. At this time, MN/D=0 was set when the groove at the tip of the convex part did not exist in the fiber.

In the present invention, the ratio (MN/D) of the distance MN from the bottom of the groove M to the tip N of the convex portion and the fiber diameter D (MN/D) is the cross-section of the fiber in the direction perpendicular to the fiber axis by embedding the multifilament with an embedding agent such as an epoxy resin. It calculates|requires by imaging|photographing an image with the magnification which can observe ten or more fibers with the HITACHI scanning electron microscope (SEM). For fibers randomly extracted within the same image from the photographed image, the cross-sectional area of the fiber in the fiber cross-section of the fiber is halved by analysis using WinROOF manufactured by Mitani Shoji, for example, as shown in Fig. 9(b). From the center of gravity G, which is the intersection of two arbitrary straight lines, the distance MN between the groove bottom M, which is the closest point to the groove surface, and the tip N of the convex part, which is the furthest point, was calculated.

Moreover, the diameter D of the said fiber was measured to the 1st decimal place in the micrometer unit. At this time, when the fiber cross-section in the direction perpendicular to the fiber axis is not a perfect circle, a value obtained by measuring the area and converting to a circle was adopted as the fiber diameter D.

For the obtained distance MN from the bottom of the groove M to the tip N of the convex portion and the fiber diameter D, the ratio (MN/D) was calculated to the fourth decimal place, and this operation was performed for 10 randomly extracted fibers. MN/D was obtained as the simple number average of , and rounded up to the third decimal place.

O. Tactile evaluation (glossy, lightness, flexibility, repulsion, dry feeling)

An 8-sheet satin fabric was prepared by adjusting the number of fibers so that the warp direction cover factor (CFA) was 800 and the weft direction cover factor (CFB) was 1200. However, CFA and CFB as used herein means that the light density and weft density of the fabric are measured in a 2.54 cm section according to JIS-L-1096:2010 8.6.1, and CFA = light density × (fineness of the warp) ^1/2 , CFB = weft density x (fineness of weft) ^1/2 It is a value obtained from the formula. Five touches of glossiness, lightness, flexibility, repulsion, and dry feeling were evaluated for the obtained fabric by using the following method.

For glossiness, use an automatic variable-angle photometer (GONIOPHOTOMETER GP-200 type) manufactured by Shikisai Murakami, Kijutsu, Inc. It calculated|required by reflected light distribution measurement, and calculated the value obtained by dividing the maximum light intensity (specular reflection) in the vicinity of a light receiving angle of 60° by the minimum light intensity (diffuse reflection) in the vicinity of a light receiving angle of 0°. This operation was performed 3 times per one place, and the simple number average of the results performed for a total of 10 places was obtained, and the value obtained by rounding off the second place of the decimal point was set as the contrast gloss. From the obtained contrast glossiness, the glossiness was evaluated in three stages based on the following criteria, respectively.

S: Excellent gloss (contrast gloss <1.6)

A: good gloss (1.6≤contrast gloss<1.9)

C: Poor gloss (1.9≤contrast gloss)

The lightness is measured by measuring the thickness (cm) of the fabric of 20 cm × 20 cm using a static pressure thickness meter (PG-14J) manufactured by Terotech, and after calculating the volume of the fabric, the weight (g) of the fabric is obtained. The value divided by , was taken as the apparent density (g/cm 3 ) of the fabric. From the obtained apparent density, lightness was evaluated in three stages based on the following criteria, respectively.

S: Excellent lightness (apparent density ≤0.33)

A: good lightness (0.34<apparent density ≤0.39)

C: poor lightness (0.4<apparent density)

For flexibility, a fabric of 20 cm × 20 cm is held with an effective sample length of 20 cm × 1 cm using a net bending tester (KES-FB2) manufactured by Katotech, and the maximum curvature in the weft direction is ±2.5 cm ^-1 . The value obtained by dividing the difference in bending moment per unit width (gf·cm/cm) of curvatures 0.5cm ^-1 and 1.5cm ^-1 when applied by 1cm ^-1 of the curvature difference and the curvature -0.5cm ^-1 and -1.5cm ^-1 The average value of the value obtained by dividing the difference in bending moment per unit width (gf·cm/cm) by the difference in curvature of 1 cm ^-1 was calculated. This operation is performed 3 times per location, a simple number average of the results of this operation for a total of 10 locations is rounded up to the fourth place of the decimal point, and the value divided by 100 is divided by the bending hardness B×10 ^-2 (gf·cm2/cm ) was made. From the obtained bending hardness Bx10 ^-2 , the softness|flexibility was evaluated in three stages based on the following criteria, respectively.

S: Excellent flexibility (bending hardness B×10 ^-2 ≤1.0)

A: good flexibility (1.0<bending hardness B×10 ^-2 ≤1.9)

C: Poor flexibility (1.9 < bending hardness B×10 ^-2 ).

The sense of repulsion is that the curvature when bending in the weft direction is ±1.0 cm ^-1 by holding a 20 cm × 20 cm fabric with an effective sample length of 20 cm × 1 cm using a Katotech net bending tester (KES-FB2). The width (gf·cm/cm) of the hysteresis was calculated. This operation is performed 3 times per place, and the simple number average of the results of this operation for a total of 10 places is rounded up to the fourth place of the decimal point, and the value divided by 100 is divided by 100 for bending recovery 2HB×10 ^-2 (gf·cm/cm ) was made. From the obtained bending recovery 2HB×10 ⁻² , the sense of repulsion was evaluated in three stages based on the following criteria, respectively.

S: Excellent repulsion (bending recovery 2HB×10 ^-2 ≤1.0)

A: Good repulsion (1.0<bending recovery 2HB×10 ^-2 ≤1.9)

C: Poor sense of repulsion (1.9<bending recovery 2HB×10 ^-2 )

For dry feeling, using an automated surface testing machine (KES-FB4) made by Katotech, a 50g load was applied to a 1cm×1cm terminal wound with a piano wire in a range of 10cm×10cm of a 20cm×20cm fabric to 1.0. The average coefficient of friction MIU was obtained by sliding at a speed of mm/sec. This operation was performed 3 times per one place, the simple number average of the result of doing this for a total of 10 places was obtained, and the value rounded up to the second place of the decimal point was used as the friction coefficient. From the obtained friction coefficient, dry feeling was evaluated in three stages based on the following criteria, respectively.

S: Excellent dry feeling (0.7 ≤ coefficient of friction)

A: Good dry feeling (0.3≤friction coefficient <0.7)

C: Poor dry feeling (coefficient of friction <0.3)

P. chromogenic

An 8-sheet satin fabric was prepared by adjusting the number of fibers so that the warp direction cover factor (CFA) was 800 and the weft direction cover factor (CFB) was 1200. The resulting fabric was dyed black using a disperse dye Sumikaron Black S-3B (10% owf). The L value of the fabric after dyeing was evaluated from the reflection measurement of the fabric using Konica Minolt's CM-3700A. This operation was measured three times per place, and the simple number average of the results performed for a total of 10 places was obtained, and the value obtained by rounding off the first decimal place was set as the black dye L value. From the obtained black dye L value, color development was judged in three stages based on the following criteria.

S: Excellent color development (black dyeing L value <15)

A: Good color development (15≤black L value <18)

C: Poor color development (18 ≤ black dye L value)

Q. Wear resistance

A plain fabric was prepared by adjusting the number of fibers so that the warp direction cover factor (CFA) was 1100 and the weft direction cover factor (CFB) was 1100. The resulting fabric was dyed black using a disperse dye Sumikaron Black S-3B (10% owf). The fabric after dyeing was cut into a circular shape with a diameter of 10 cm, wetted with distilled water, and adhered to the master. In addition, the fabric cut into 30 cm × 30 cm was fixed on a horizontal plate while it was dried. The disk wetted with distilled water is brought into contact with the fabric fixed on a horizontal plate, and the disk is moved in a circular motion at a load of 420 g and a speed of 50 rpm for 10 minutes so that the center of the disk draws a circle with a diameter of 10 cm. of the fabric was rubbed. After leaving the friction for 4 hours, the degree of discoloration and discoloration of the fabric attached to the disk was judged on a grade of 1 to 5 in units of 0.5 grade using a gray scale for discoloration and discoloration. From the result of the obtained grade judgment, abrasion resistance was judged in 3 steps based on the following reference|standard.

S: Excellent abrasion resistance (Class 4 or higher)

A: Good wear resistance (Class 3 or 3-4)

C: Poor abrasion resistance (Classification: less than Class 3)

[Example 1]

Polyethylene terephthalate (SSIA-PEG copolymerized PET, melt viscosity: 100 Pa·s, melting point: 233°C) copolymerized with 8 mol% of 5-sodium sulfoisophthalic acid and 9 wt% of polyethylene glycol as Polymer 1, Polyethylene terephthalate as Polymer 2 (PET, melt viscosity: 130 Pa·s, 254°C) was prepared.

After melting each of these polymers at 290°C, the polymer 1/polymer 2 is weighed so that the weight ratio is 30/70 and introduced into the spinning pack equipped with the composite nozzle shown in FIG. 12, as shown in FIG. 5(a). As a core-sheath composite fiber of a perfect circular shape, the polymer introduced from the discharge hole was discharged from the discharge hole so as to form a composite structure in which the sheath component was completely coated with a core component having a groove at the tip of the convex portion of the three-leaf cross section. At this time, it arrange|positions so that the sheath component may become polymer 1, and the core component may become polymer 2.

After cooling and solidifying the discharged composite polymer, an oil agent was applied, wound at a spinning speed of 1500 m/min, and stretching was performed between rollers heated to 90° C. and 130° C. to prepare a core-sheath composite fiber of 56 dtex-36 filaments.

The obtained ratio of the minimum thickness to the fiber diameter (Smin/D) of the obtained sheath component was 0.03, and the ratio of the maximum thickness to the minimum thickness of the sheath component (Smax/Smin) was 16. In addition, the ratio (GN/GM) of the distance GM from the center of gravity G of the seam component to the bottom M of the groove and the distance GN from the center of gravity G of the seam component to the tip N of the convex part is 1.42, could confirm that

In addition, the ratio of the inscribed circle diameter _{R A} and the circumscribed circle diameter RB of the core sheath composite fiber is 1.0, and since it is easy to fill the closest packing when it exists as a multifilament, the voids between fibers obtained after elution with a sheath component are uniformly without non-uniformity. it could be done

Multifilaments comprising the core component of the core sheath composite fiber by treating the resulting fabric woven of the core sheath composite fiber in a 1 wt% aqueous sodium hydroxide solution (bath ratio 1:50) heated to 90°C to remove 99% or more of the sheath component (fiber diameter 10 μm) to obtain a fabric composed of.

In the fabric composed of the multi-filament, the super component completely covering the multi-leaf-shaped core component is eluted, so that fine interfiber voids of less than 5 μm and fine fibers of 10 μm or more are formed between each fiber such as natural silk among the multi-filaments. In terms of expressing a pore structure in which voids between fibers are uniformly present, good gloss (contrast gloss: 1.7) and repulsion (bending recovery 2HB: 0.6×10 ^-2 gf cm/cm) without viewing angle dependence It has a dry feeling (friction coefficient: 0.7), good lightness (apparent density: 0.40 g/cm3) and flexibility (bending hardness B: 0.7×10 ^-2 gf·cm2/cm), giving it a texture close to natural silk. there was.

In addition, when the fabric is dyed black, excellent color development (black dyeing L value: 14) is expressed due to diffused reflection of light in the inter-fiber voids uniformly between the single fibers and the grooves at the tip of the convex part of the heteromorphic cross-sectional fiber. , it was found to have good abrasion resistance (class 3-4) without discoloration or discoloration due to fibrillation in the groove portion. A result is shown in Table 1-1.

[Examples 2 and 3]

Except for changing the weight ratio of Polymer 1/Polymer 2 to 20/80 (Example 2) and 10/90 (Example 3), everything was carried out according to Example 1.

In Examples 2 and 3, as the amount of supernatant was decreased, the flexural hardness increased, so that the woven fabric had a characteristic elastic feel while leaving a natural silk-like texture. Moreover, it was excellent also in abrasion resistance because the groove part at the tip of the convex part of the fiber in a multifilament became shallow. A result is shown in Table 1-1.

[Example 4]

Except for changing the composite structure of the core-sheath composite fiber to Fig. 2 (a), all was carried out according to Example 1.

In Example 4, since the groove part at the tip of the convex part of the fiber in the multifilament disappeared, diffused reflection of light was reduced, the reflection intensity improved, and the visibility of glossiness increased. Moreover, it was excellent also in abrasion resistance. A result is shown in Table 1-1.

[Comparative Example 1]

Polyethylene terephthalate (SSIA-PEG copolymerized PET, melt viscosity: 100 Pa·s, melting point: 233°C) copolymerized with 8 mol% of 5-sodium sulfoisophthalic acid and 9 wt% of polyethylene glycol as Polymer 1, Polyethylene terephthalate as Polymer 2 (PET, melt viscosity: 130 Pa·s, 254°C) was prepared.

After melting each of these polymers at 290°C, the polymer 1/polymer 2 is weighed so that the weight ratio is 30/70 and introduced into the spinning pack equipped with the composite nozzle shown in FIG. 12, as shown in FIG. 3(a). As a core-sheath composite fiber of a perfect circle shape, the inflow polymer was discharged from the discharge hole so as to have a simple composite structure in which a core component of a round cross section was coated with a sheath component. At this time, it arrange|positions so that the sheath component may become polymer 1, and the core component may become polymer 2.

After cooling and solidifying the discharged composite polymer, an oil agent was applied, wound at a spinning speed of 1500 m/min, and stretching was performed between rollers heated to 90° C. and 130° C. to prepare a core-sheath composite fiber of 56 dtex-36 filaments.

Multifilaments comprising the core component of the core sheath composite fiber by treating the resulting fabric woven of the core sheath composite fiber in a 1 wt% aqueous sodium hydroxide solution (bath ratio 1:50) heated to 90°C to remove 99% or more of the sheath component (fiber diameter 10 μm) to obtain a fabric composed of.

In the obtained fabric, coarse interfiber voids of 10 μm or more exist between each fiber in the multifilament, but fine interfiber voids of less than 5 μm do not exist. There was a lack of reaction. Moreover, since a convex part and a groove part did not exist in a seam component, the dry feeling was also lacking. A result is shown in Table 1-1.

[Comparative Example 2]

All were carried out according to Comparative Example 1 except for changing the composite structure of the core-sheath composite fiber to Fig. 3(b).

In Comparative Example 2, since it is a core component of a three-leaf cross section, the dry feeling is slightly improved, but again, after the dissolution of the sheath component, fine interfiber voids of less than 5 μm do not exist between each fiber, so that lightness or repulsion is reduced. it was lacking. A result is shown in Table 1-1.

[Comparative Example 3]

Polyethylene terephthalate (SSIA-PEG copolymerized PET, melt viscosity: 100 Pa·s, melting point: 233°C) copolymerized with 8 mol% of 5-sodium sulfoisophthalic acid and 9 wt% of polyethylene glycol as Polymer 1, Polyethylene terephthalate as Polymer 2 (PET, melt viscosity: 130 Pa·s, 254°C) was prepared.

After melting each of these polymers at 290°C, the polymer 1/polymer 2 is weighed so that the weight ratio is 5/95 and introduced into the spinning pack equipped with the composite nozzle shown in FIG. 12, as shown in FIG. 6(a). The polymer flowing in from the discharge hole is discharged from the discharge hole so as to form a composite structure in which the dissolving component is arranged at the tip of the convex portion of the three-lobed poorly dissolving component described in Japanese Unexamined Patent Application Publication No. 57-5912 A. ejected At this time, it was arrange|positioned so that the easily eluting component may become polymer 1, and the hardly eluting component may become polymer 2.

After cooling and solidifying the discharged composite polymers, an oil agent was applied, wound at a spinning speed of 1500 m/min, and stretching was performed between rollers heated to 90° C. and 130° C. to prepare a 56 dtex-36 filament composite fiber.

Multifilaments ( A fabric consisting of a fiber diameter of 12 μm) was obtained.

In Comparative Example 3, the friction coefficient was high because the tip of the convex part of the trilobular heteromorphic cross-sectional fiber had a deep groove tapering in the inner direction of the fiber, and the dry feeling was excellent, but the abrasion resistance was inferior. In addition, after the dissolution of the sheath component, coarse interfiber voids of 10 μm or more did not exist between each fiber, so it was a dazzling luster that lacked a sense of quality, and also lacked lightness, flexibility, and repulsion. A result is shown in Table 1-2.

[Examples 5 and 6]

All were carried out in accordance with Example 4 except that the discharge amount was changed so that the fiber diameters of the deformable cross-sectional fiber composed only of the core component of the core sheath composite fiber were 14 µm (Example 5) and 17 µm (Example 6).

In Examples 5 and 6, by increasing the fiber diameter, the unevenness due to the fiber cross section of the fiber in the multifilament obtained after super-eluting is three-lobed cross section is emphasized, the reflection strength is higher, and the visibility of the gloss of the obtained fabric is further increased it was In addition, since the bending hardness was increased, a characteristic elastic texture was obtained while leaving a texture like natural silk. A result is shown in Table 1-2.

[Example 7]

All were carried out according to Example 4 except for changing the composite structure of the core-sheath composite fiber to Fig. 2(b).

In Example 7, since the fiber cross section of the fibers in the multifilament was changed from a three-lobe cross-section to a four-lobe cross-section, the diffuse reflection of light at the convex portion increased, and not only a high-quality gloss was obtained, but also friction was improved, and the dry feeling was improved. A woven fabric with increased tactile feel was obtained. A result is shown in Table 1-2.

[Comparative Example 4]

Polyethylene terephthalate (SSIA-PEG copolymerized PET, melt viscosity: 100 Pa·s, melting point: 233°C) copolymerized with 8 mol% of 5-sodium sulfoisophthalic acid and 9 wt% of polyethylene glycol as Polymer 1, Polyethylene terephthalate as Polymer 2 (PET, melt viscosity: 130 Pa·s, 254°C) was prepared.

After melting each of these polymers at 290°C, the polymer 1/polymer 2 is weighed so that the weight ratio is 20/80 and introduced into the spinning pack equipped with the composite nozzle shown in FIG. 12, as shown in FIG. 3(c). The inflow polymer was discharged from the discharge hole so that the easily dissolving component described in Unexamined-Japanese-Patent No. 2010-222771 might become the composite structure which divided|segmented the hardly eluting component into plural pieces. At this time, it was arrange|positioned so that the easily eluting component may become polymer 1, and the hardly eluting component may become polymer 2.

After cooling and solidifying the discharged composite polymers, an oil agent was applied, wound at a spinning speed of 1500 m/min, and stretching was performed between rollers heated to 90° C. and 130° C. to prepare a 56 dtex-18 filament composite fiber.

Multifilaments ( A fabric consisting of a fiber diameter of 6 μm) was obtained.

In Comparative Example 4, although the fibers in the multifilaments were excellent in gloss and flexibility because the fibers had a fine fiber diameter, fine interfiber voids of less than 5 μm and coarse interfiber voids of 10 μm or more were uniformly formed between each fiber. It didn't exist, so it lacked lightness or repulsion. In addition, it was difficult to be dyed with dyes due to the diameter of the fine fibers and lacked color development. A result is shown in Table 1-2.

[Example 8]

Polyethylene terephthalate (SSIA-PEG copolymerized PET, melt viscosity: 100 Pa·s, melting point: 233°C) obtained by copolymerization of 8 mol% of 5-sodium sulfoisophthalic acid and 9 wt% of polyethylene glycol as polymer 1, and isophthalic acid as polymer 2 Polyethylene terephthalate (PET, melt viscosity: 130 Pa.s, melting point: 254 ° C.) was prepared as 7 mol% copolymerized polyethylene terephthalate (IPA copolymerized PET, melt viscosity: 140 Pa s, melting point: 232 ° C.), as the polymer 3 .

Each of these polymers was melted at 290° C., and then polymer 1/polymer 2/polymer 3 were weighed so as to be 30/35/35 in a weight ratio, and introduced into a spinning pack equipped with a compound nozzle shown in FIG. 12, and FIG. 5(b). ) as shown in Fig. ), wherein the core component is completely coated with the sheath component, the core component is divided into two by the sheath component, and the divided core component 1 and the divided core component 2 have 3 leaves. Inflow polymer was discharged from the discharge hole so that it might become a composite structure with a groove|channel in the front-end|tip of the convex part of a cross section. At this time, it arrange|positions so that the sheath component may become the polymer 1, the core component 1 may become the polymer 2, and the core component 2 may become the polymer 3.

After cooling and solidifying the discharged composite polymers, an oil agent was applied, wound at a spinning speed of 1500 m/min, and stretching was performed between rollers heated to 90° C. and 130° C. to prepare a core-sheath composite fiber of 56 dtex-18 filaments.

The obtained ratio of the minimum thickness to the fiber diameter (Smin/D) of the obtained sheath component was 0.03, and the ratio of the maximum thickness to the minimum thickness of the sheath component (Smax/Smin) was 12. In addition, the ratio (GN/GM) of the distance GM from the center of gravity G of the seam component to the bottom M of the groove and the distance GN from the center of gravity G of the seam component to the tip N of the convex part is 1.38, could confirm that

In addition, the ratio of the inscribed circle diameter _{R A} to the circumscribed circle diameter RB of the core-sheath composite fiber is 1.8, and when it exists as a multifilament, it is easy to fill the closest packing, so that the voids between the fibers obtained after elution with a sheath component are uniformly without non-uniformity. it could be done

After removing 99% or more of the sheath component by treating the fabric woven with the obtained core sheath composite fiber in a 1 wt% aqueous sodium hydroxide solution (bath ratio 1:50) heated to 90 ° C., heat treatment with wet heat at 130 ° C. A fabric composed of multifilaments (fiber diameter of 10 µm) composed of a core component of the core-sheath composite fiber was obtained.

In the fabric composed of the multi-filament, the super component completely covering the multi-leaf-shaped core component is eluted, so that fine inter-fiber voids of less than 5 μm and coarse fibers of 10 μm or more are eluted between each fiber such as natural silk. Since the void structure in which the voids are uniformly present is expressed, and the shim component 1 and the shim component 2 have different shrinkage differences, the difference in yarn length is expressed by heat treatment after elution of the sheath component, compared with Example 1 As a result, the pores between fibers of 10 μm or more became coarse, and thus had a pore structure more similar to that of natural silk. In addition, the texture has a high ^- quality gloss (contrast gloss: 1.4) without viewing angle dependence, and a dry feeling (coefficient of friction: 0.8) and very light (apparent density: 0.32 g/cm3) and excellent flexibility (bending hardness B: 0.9×10 ^-2 gf·cm2/cm), and it was a fabric with a texture like natural silk. .

In addition, when the fabric is dyed black, the diffuse reflection of light is more emphasized and excellent color development (black dyeing L value: 13) is expressed, and good abrasion resistance (3-4) without discoloration due to fibrillation in the groove portion. class) was also found. A result is shown in Table 2-1.

[Examples 9 and 10]

Except for changing the polymer 2 to polypropylene terephthalate (PPT) (Example 9) and polyethylene terephthalate (PET) (Example 10), it was all carried out according to Example 8.

In Example 9, the rubber elasticity characteristic of PPT was harmonized to express a more flexible feel, and it was a fabric having a unique stretch function not found in natural silk. In addition, since PPT has a low refractive index compared to PET, the obtained fabric was also excellent in color development.

In Example 10, the difference in yarn length was not expressed, but a natural silk-like texture was sufficiently expressed, and in that the core component was divided into two, fine interfiber voids of less than 5 μm and coarse fibers of 10 μm or more were compared to Example 1 The voids between the fibers were more uniformly present, and the lightness, flexibility, and repulsion feeling of the obtained fabric were improved. A result is shown in Table 2-1.

[Example 11]

Except for changing the composite structure of the core-sheath composite fiber to Fig. 4 (a), all was carried out according to Example 8.

In Example 11, since the groove part at the tip of the convex part of the deformable cross-sectional fiber disappeared, the diffuse reflection of light was reduced, the reflection intensity was increased, and the visibility of the luster was increased. Moreover, it was excellent also in abrasion resistance. A result is shown in Table 2-1.

[Examples 12 and 13]

Example 8 except that the composite structure of the core-sheath composite fiber is shown in Fig. 4(a), and the weight ratio of Polymer 2/Polymer 3 is changed to 50/20 (Example 12) and 20/50 (Example 13). carried out according to

In Examples 12 and 13, as the ratio of polymer 2, which is a high shrinkage component, is increased, the yarn length difference is strongly expressed, and the lightness of the resulting fabric increases. The strength was increased, the visibility of the gloss was increased, and the shrinkage due to the high shrinkage rate of the high shrinkage component in the moist heat treatment was suppressed, and the flexibility and the repulsion were excellent. A result is shown in Table 2-1 and Table 2-2.

[Example 14]

All were implemented in accordance with Example 8 except that the composite structure of the core-sheath composite fiber was made into Fig. 4 (a), and the irregularity ( _{RB /R A )} was changed to 3.0.

Since the release degree of the core component also increases as the release degree of the core sheath composite fiber increases, the unevenness due to the fiber cross section of the fiber in the multifilament obtained after super elution being three-lobed cross section is emphasized, the reflective strength becomes higher, and the visibility of the luster of the obtained fabric This was increasing further. A result is shown in Table 2-2.

[Example 15]

All were implemented according to Example 8 except changing the composite structure of the core-sheath composite fiber into FIG. 4(b) and the irregularity ( _{RB /R A =} 1.0).

The smaller the release degree of the core sheath composite fiber, the easier it is to fill in the tightest packing when it exists as a multifilament. As a result, the voids between fibers obtained after elution with the sheath component can be made uniform without non-uniformity, and the quality of the resulting fabric is improved. A result is shown in Table 2-2.

[Example 16]

All were implemented according to Example 8 except changing the composite structure of the core-sheath composite fiber to FIG. 4(c) and the irregularity ( _{RB /R A =} 1.0).

In Example 16, since the core component is divided into six by the sheath component, the fiber diameter of the deformable cross-section fiber obtained after removing the sheath component becomes thinner, resulting in a milder, higher-quality gloss as well as excellent flexibility. This was what was obtained. A result is shown in Table 2-2.

[Comparative Example 5]

Polyethylene terephthalate (SSIA-PEG copolymerized PET, melt viscosity: 100 Pa·s, melting point: 233°C) obtained by copolymerization of 8 mol% of 5-sodium sulfoisophthalic acid and 9 wt% of polyethylene glycol as polymer 1, and isophthalic acid as polymer 2 Polyethylene terephthalate (PET, melt viscosity: 130 Pa.s, melting point: 254 ° C.) was prepared as 7 mol% copolymerized polyethylene terephthalate (IPA copolymerized PET, melt viscosity: 140 Pa s, melting point: 232 ° C.), as the polymer 3 .

After melting each of these polymers at 290° C., the polymer 1/polymer 2/polymer 3 was weighed so that the weight ratio was 5/42.5/42.5, and introduced into a spinning pack equipped with a compound nozzle shown in FIG. 12, and FIG. 6(b) ) as shown in Japanese Patent Application Laid-Open No. Hei 2-145825, in which the dissolving component is arranged at the tip of the convex part of the 3-lobed poorly dissolving component in a tapered shape in the inner direction of the fiber, The inflow polymer was discharged from the discharge hole so that the eluted component was composed of two types of polymers, a high-shrinkage component and a low-shrink component. At this time, it was arrange|positioned so that the easily dissolving component may become Polymer 1, the high shrinkage component in a poorly eluted component may become Polymer 2, and the low shrinkage component may become Polymer 3.

After cooling and solidifying the discharged composite polymer, an emulsion is applied, wound at a spinning speed of 1500 m/min, and stretching is performed between rollers heated to 90° C. and 130° C. to obtain 56 dtex-36 filaments (high shrinkage: 28 dtex-18 filaments). , low shrinkage: 28dtex-18 filaments) were prepared.

The obtained composite fiber woven fabric is treated in 1 wt% sodium hydroxide aqueous solution (bath ratio 1:50) heated to 90°C to remove 99% or more of the super component, and then heat-treated with wet heat at 130°C. A woven fabric composed of multifilaments (fiber diameter of 12 µm) composed of a component of the composite fiber hardly eluting was obtained.

In Comparative Example 5, the friction coefficient was high because the tip of the convex portion of the trilobed heteromorphic cross-sectional fiber had a deep groove tapering in the fiber inner direction, and the dry feeling was excellent, but the abrasion resistance was inferior. In addition, although lightness is obtained by the expression of the crimped form due to the difference in heat shrinkage between the high shrinkage component and the low shrinkage component, fine interfiber voids of less than 5 μm and coarse interfiber voids of 10 μm or more between each fiber In addition to this non-uniform existence, shrinkage also occurred due to the high shrinkage rate of the high shrinkage component, resulting in a lack of flexibility and repulsion. A result is shown in Table 2-2.

[Example 17]

Polyethylene terephthalate (SSIA-PEG copolymerized PET, melt viscosity: 100 Pa·s, melting point: 233°C) obtained by copolymerization of 8 mol% of 5-sodium sulfoisophthalic acid and 9 wt% of polyethylene glycol as polymer 1, and isophthalic acid as polymer 2 Polyethylene terephthalate (PET, melt viscosity: 130 Pa.s, melting point: 254 ° C.) was prepared as 7 mol% copolymerized polyethylene terephthalate (IPA copolymerized PET, melt viscosity: 140 Pa s, melting point: 232 ° C.), as the polymer 3 .

After melting each of these polymers at 290°C, the polymer 1/polymer 2/polymer 3 is weighed so that the weight ratio is 30/35/35 and introduced into a spinning pack equipped with a compound nozzle shown in FIG. 12, and FIG. 10(b) ) as a core-sheath composite fiber, in which the sheath component completely coats the core component, the core component is divided into two by the sheath component, and the divided core component 1 and core component 2 are each convex in the three-leaf cross section Inflow polymer was discharged from the discharge hole so that it might become a composite structure with a groove|channel in the sub-tip. At this time, it arrange|positions so that the sheath component may become the polymer 1, the core component 1 may become the polymer 2, and the core component 2 may become the polymer 3.

After cooling and solidifying the discharged composite polymers, an oil agent was applied, wound at a spinning speed of 1500 m/min, and stretching was performed between rollers heated to 90° C. and 130° C. to prepare a core-sheath composite fiber of 56 dtex-18 filaments.

The obtained ratio of the minimum thickness to the fiber diameter (Smin/D) of the obtained sheath component was 0.03, and the ratio of the maximum thickness to the minimum thickness of the sheath component (Smax/Smin) was 12. In addition, the ratio (GN/GM) of the distance GM from the center of gravity G of the seam component to the bottom M of the groove and the distance GN from the center of gravity G of the seam component to the tip N of the convex part is 1.38, could confirm that

In addition, the ratio of the inscribed circle diameter _{R A} to the circumscribed circle diameter RB of the core-sheath composite fiber is 1.8, and when it exists as a multifilament, it is easy to fill the closest packing, so that the voids between the fibers obtained after elution with a sheath component are uniformly without non-uniformity. it could be done

After heat-treating the fabric woven with the obtained core sheath composite fiber with wet heat at 130 ° C, treatment in 1 wt % sodium hydroxide aqueous solution (bath ratio 1:50) heated to 90 ° C to remove 99% or more of the sheath component, , obtained a fabric composed of multifilaments in which crimpable fibers composed of different polymers are uniformly mixed. The obtained crimped fiber had a composite structure (irregularity: 1.6) with a groove (MN/D: 0.13) at the tip of the convex part of the three-leaf cross section, the fiber diameter was 10 μm, the number of crimps was 14 threads/cm, and the melting point was The difference in yarn length of the crimped fibers composed of these different polymers was 7%.

The fabric made of the multifilaments has a difference in heat shrinkage of polymers with different melting points and between coarse fibers of 10 μm or more between fibers due to the exclusion volume effect between fibers due to the expression of a crimped form in moist heat treatment. Not only voids are formed, but interfiber voids of less than 5 μm are formed between the crimped fibers made of adjacent polymers with different melting points. It had a pore structure similar to the voids between fibers of natural silk, in which the voids were more uniformly mixed. As a result of evaluating the pore structure, the average inter-fiber void distance: 10.5 µm, the ratio of the inter-fiber void distance of less than 5 µm: 25%, and the porosity: 65%.

In addition, the fabric has a high-quality gloss (contrast gloss: 1.4) without viewing angle dependence, but is very light (apparent density: 0.32 g/cm 3 ) and has a dry feeling (coefficient of friction: 0.8) and is more stable than Example 8 By forming an inter-fiber void distance of less than 5 μm, the feeling of repulsion (bending recovery 2HB: 0.7×10 ^-2 gf·cm/cm) and flexibility (bending hardness B: 0.8×10 ^-2 gf·cm/cm) are more It was excellent and had a texture like natural silk.

In addition, when the fabric is dyed black, diffuse reflection of light is more emphasized in the coarse inter-fiber voids of 10 μm or more uniformly present between fibers, and excellent color development (black dyeing L value: 13) is expressed, and in the groove It turned out that it also has good abrasion resistance (3-4 grade) without discoloration and discoloration by fibrillation. A result is shown in Table 3.

[Examples 18 and 19]

Example 17 was followed except that the weight ratio of polymer 1/polymer 2/polymer 3 was changed to 20/40/40 (Example 18) and 10/45/45 (Example 19).

In Examples 18 and 19, the ratio of the inter-fiber void distance of less than 5 μm of the multifilaments increases as the amount of the super component is reduced, and accordingly, the bending hardness increases, so that the texture is elastic while leaving a natural silk-like texture. It was made of woven fabric. Moreover, it was excellent in abrasion resistance as the groove part at the tip of the convex part of the crimpable fiber became shallow. A result is shown in Table 3.

[Example 20]

Except for changing the polymer 2 to polypropylene terephthalate (PPT, melt viscosity: 150 Pa·s, melting point: 233°C), it was all carried out according to Example 17.

In Example 20, the rubber elasticity characteristic of PPT was harmonized to express a more flexible feel, and it was a fabric having a unique stretch function not found in natural silk. In addition, since PPT has a low refractive index compared to PET, the obtained fabric was also excellent in color development. A result is shown in Table 3.

[Example 21]

All were carried out according to Example 17 except for changing to polyethylene terephthalate (high-viscosity PET, melt viscosity: 250 Pa·s, melting point: 254°C) having a high melt viscosity as the polymer 2.

In Example 5, since the number of crimps of the crimpable fibers constituting the multifilaments is reduced by expressing the crimping by the viscosity difference rather than the melting point difference between the polymer 3 and the polymer 2, the diffuse reflection of light due to the pore structure of the multifilaments is suppressed, It was to increase the visibility of the gloss. In addition, since the expression of the crimped form in the wet heat treatment was reduced, the ratio of the inter-fiber void distance of less than 5 μm was also increased, and the repulsion was excellent. A result is shown in Table 3.

[Comparative Example 6]

Polyethylene terephthalate (SSIA-PEG copolymerized PET, melt viscosity: 100 Pa·s, melting point: 233°C) obtained by copolymerization of 8 mol% of 5-sodium sulfoisophthalic acid and 9 wt% of polyethylene glycol as polymer 1, and isophthalic acid as polymer 2 Polyethylene terephthalate (PET, melt viscosity: 130 Pa.s, melting point: 254 ° C.) was prepared as 7 mol% copolymerized polyethylene terephthalate (IPA copolymerized PET, melt viscosity: 140 Pa s, melting point: 232 ° C.), as the polymer 3 .

Each of these polymers was melted at 290° C., and then polymer 1/polymer 2 was weighed to be 2.5/47.5 by weight and polymer 1/polymer 3 was weighed to be 2.5/47.5 by weight, and the spinneret was placed in a spinning pack equipped with a compound nozzle shown in FIG. A composite in which the dissolving component is placed at the tip of the convex part of the 3-lobed poorly dissolving component described in Japanese Patent Application Laid-Open No. 2-145825, as shown in FIG. 11, in a shape that tapers in the direction of the fiber The inflow polymer was discharged so that a composite fiber composed of two components, a high-shrinkage component and a dissolving component, and a composite fiber composed of two components, a low-shrinkage component and a dissolving component, were discharged from each discharge hole. At this time, it arrange|positioned so that the used-out component may be polymer 1, the high-shrinkage component is polymer 2, and the low-shrinkage component is polymer 3.

After cooling and solidifying the discharged composite polymer, an emulsion is applied, wound at a spinning speed of 1500 m/min, and stretching is performed between rollers heated to 90° C. and 130° C. to obtain 56 dtex-36 filaments (high shrinkage: 28 dtex-18 filaments). , low shrinkage: 28dtex-18 filaments) were prepared.

The resulting composite fiber woven fabric was heat treated with wet heat at 130° C., and then treated in 1 wt% sodium hydroxide aqueous solution (bath ratio 1:50) heated to 90° C. to remove 99% or more of the sheath component. A woven fabric composed of multifilaments (fiber diameter of 12 μm) composed of a component of the composite fiber hardly eluted was obtained.

In Comparative Example 6, the friction coefficient was high, and the dry feeling was excellent, but the abrasion resistance was inferior because the tip of the convex part of the trilobular heteromorphic cross-sectional fiber had a deep groove tapering in the inner direction of the fiber. In addition, lightness is obtained by the difference in the length of the yarn between the high shrinkage component and the low shrinkage component, while fibers made of different polymers are skewed and mixed in the spinning mixed fiber method, and the ratio of the void distance between the fibers of less than 5 μm is small, There was a lack of reaction. A result is shown in Table 3.

[Example 22]

Except for changing the composite structure of the core-sheath composite fiber to Fig. 10 (a), all were carried out according to Example 17.

In Example 22, when the groove part at the tip of the convex part of the crimpable fiber in the multifilament disappeared, the diffuse reflection of light was reduced, the reflection intensity became high, and the visibility of glossiness increased. Moreover, it was excellent also in abrasion resistance. A result is shown in Table 4.

[Examples 23 and 24]

Except for changing the weight ratio of polymer 2/polymer 3 to 50/20 (Example 23) and 20/50 (Example 24), everything was carried out according to Example 17.

In Examples 23 and 24, as the ratio of polymer 2, which is a high shrinkage component, was increased, the number of crimped fibers and difference in yarn length of the crimpable fibers in the multifilaments were expressed, and the average inter-fiber void distance in the pore structure of the multifilaments was increased. As the amount of polymer 3, which is a low-shrinkage component, increases, the number of crimps of the crimpable fibers in the multifilaments decreases. Visibility not only increased, but also the ratio of the inter-fiber void distance of less than 5 μm was increased due to the decrease in the expression of the crimped form in the wet heat treatment, and the repulsion was excellent. A result is shown in Table 4.

[Examples 25 and 26]

All were implemented according to Example 17 except changing the discharge amount so that the fiber diameter of the crimpable fiber in a multifilament might be set to 14 micrometers (Example 25) and 17 micrometers (Example 26).

In Examples 25 and 26, by increasing the fiber diameter, the unevenness due to the crimpable fiber in the multifilament having a three-leaf cross-section was emphasized, the reflection strength was higher, and the visibility of the gloss of the obtained fabric was further increased. Further, since the flexural hardness was increased, a characteristic elastic texture was obtained while leaving a natural silk-like texture. A result is shown in Table 4.

(industrial applicability)

In the multifilament of the present invention, two or more kinds of crimpable fibers composed of different polymers are uniformly mixed in the multifilament, so that fine interfiber voids of less than 5㎛ and 10 It is possible to form a unique pore structure in which voids between fibers of ㎛ or larger are uniformly mixed. Therefore, the textile product made of multifilaments of the present invention can reproduce various textures unique to natural silk, and it combines the ease of handling unique to synthetic fibers as well as Western and Japanese clothes in which natural silk has been mainly used in the past. , from general medical care such as underwear and underwear to sports medicine, medical materials, interior products such as carpets, sofas and curtains, vehicle interior products such as car seats, cosmetics, cosmetic masks, wiping cloths, health products, etc. It can be used suitably for textile products to be worn.

[Table 1-1]

[Table 1-2]

[Table 2-1]

[Table 2-2]

[Table 3]

[Table 4]

a Fibroin composed of a sparingly eluting component in the raw silk of natural silk
b Sericin consisting of extractable ingredients in raw silk of natural silk
c poorly soluble component
d Extraction component
A A perfect circle inscribed at two or more points in the cross section of the composite fiber (inscribed circle)
B A perfect circle circumscribed at two or more points on the cross section of the composite fiber (circumscribed circle)
C A perfect circle inscribed at two or more points in the fiber cross section (inscribed circle)
D A perfect circle circumscribed at two or more points on the fiber cross section (circumscribed circle)
F Intersection of the fiber surface and a straight line drawn from the intersection (center of gravity) of any two straight lines that bisect the area of the fiber cross-section toward any fiber surface
G Intersection (center of gravity) of any two straight lines that bisect the area of the fiber cross-section
The point closest to the intersection (center of gravity) of any two straight lines that bisect the area of the fiber cross-section on the groove surface at the tip of the convex part
N The point furthest from the intersection (center of gravity) of any two straight lines that bisect the area of the fiber cross-section on the groove surface at the tip of the convex part.
S Intersection of a straight line drawn from the intersection of any two straight lines bisecting the area of the fiber cross-section toward an arbitrary fiber surface and the outer perimeter of the seam component
Any fiber in the X multifilament
Among Y multifilaments, a fiber that is in a state where no other fibers exist on a straight line connecting the center of gravity and the center of gravity of X, and a fiber composed of a polymer different from X
1 Weighing plate
2 distribution plate
3 Discharge plate

Claims (11)

In the fiber cross section of the core sheath composite fiber made of two or more types of polymers, the sheath component completely covers the multilobed core component having three or more convex parts, and the ratio Smax/ Core sheath composite fiber with an Smin of 5.0 or higher. The method of claim 1,
In the multi-leaf-shaped shim component, the convex portion has a groove at the tip of the convex portion in the direction of the center of gravity of the shim component, the distance GM from the center of gravity G of the shim component to the bottom M of the groove, and the distance GM from the center of gravity G of the shim component to the tip N of the convex portion A core-sheath composite fiber with a distance GN and a ratio GN/GM of 1.1 to 1.5. 3. The method of claim 1 or 2,
A core-sheath composite fiber in which a core component is divided into two or more by a sheath component, and each of the divided core components has a multi-leaf shape. 4. The method of claim 3,
A core component divided by a sheath component, wherein adjacent core components are made of polymers having different melting points. A multifilament comprising the core component of the core-sheath composite fiber according to any one of claims 1 to 4. 6. The method of claim 5,
A multifilament having a pore structure in which the average interfiber void distance is 5 to 30 μm, and the proportion of which the interfiber void distance is less than 5 μm is 10 to 50%. 7. The method of claim 6,
A multifilament having a pore structure having a porosity of 30 to 80%. 8. The method according to claim 6 or 7,
A multifilament comprising two or more types of crimpable fibers composed of polymers having different melting points, wherein the crimpable fibers are uniformly mixed. 9. The method according to any one of claims 6 to 8,
A multifilament composed of multilobed fibers having three or more convex portions in a fiber cross section. 10. The method according to any one of claims 6 to 9,
A multifilament comprising fibers having a groove at the tip of the convex portion in the fiber cross section and having a distance MN from the bottom of the groove M to the tip N of the convex portion and a fiber diameter D (MN/D) of 0.04 to 0.20. The fiber product in which the core-sheath composite fiber or multifilament in any one of Claims 1-10 is contained in a part.

Images