JP2007146306A - Artificial-hair fiber - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide new artificial-hair fibers excellent in durability. <P>SOLUTION: The artificial-hair fibers comprise polyester fibers. The cross-sectional surface of each of the polyester fibers has a spectacle shape. A constriction ratio of the fiber is 2.5-8, and the surface of the fiber has unevenness. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

The present invention relates to a novel artificial hair fiber. More specifically, the present invention relates to a novel artificial hair fiber made of polyester fiber and having excellent durability.

  Conventionally, various synthetic fibers have been used as materials for artificial hair used in wigs, hair wigs, extensions, hair bands, and the like. However, since the polyvinyl chloride fiber that has been frequently used has a low strength, there is a problem that when the hair is subjected to a waving treatment and is conditioned, it is easily cut with a slight catch.

  Furthermore, since the dyeing fastness is low, there is also a problem that even those dyed with a cationic dye having relatively excellent light resistance are easily discolored by light received while wearing a wig. For this reason, in the case of black artificial hair, a method in which a black pigment is mixed with a fiber raw material and then produced is used, but the resulting fiber has a large surface reflected light, so the blackness like natural hair is not high. The actual situation is not obtained.

  In addition, since the polyvinyl chloride fiber has low durability against the heating set, curls and waves tend to disappear under conditions such as bathing, showering, sauna and sunlight. For this reason, when artificial hair is partially worn, only artificial hair is discolored, so that there is also a problem that it can be seen at first glance that it is artificial hair. In addition, since static electricity is easily generated due to friction during hair shaping, reverse hairs and dust are easily attached.

  In order to solve such problems, various fibers made of a saturated polyester represented by polyethylene terephthalate, which are excellent in properties such as tensile strength, heat resistance, and set retention, have been studied. Certainly, artificial hair fibers made of saturated polyester have excellent properties such as easy setability, set retention, combability, and light discoloration. Since it is flat and the refractive index of polyester itself is high, the surface gloss is strong, and the appropriate matteness and color close to human hair required for artificial hair have not been sufficiently obtained.

In order to improve such defects, various techniques for matting the surface of polyester fibers have been proposed. For example, a method has been proposed in which a number of scratches are formed on the surface of a polyester fiber to roughen the surface. However, the fiber obtained by this method has a problem that the fiber strength is lowered due to scratches formed on the fiber surface. As another method, Japanese Patent Application Laid-Open No. 63-12716 (Patent Document 1) discloses that a fiber made of polyester containing fine particles such as silicon oxide is treated with an alkaline aqueous solution, and specific fine irregularities are formed on the fiber surface. There has been proposed a method for forming the film. Certainly, according to this method, although artificial hair excellent in a certain degree of matting property and color tone can be obtained, satisfactory hair has not yet been obtained.
JP 63-12716 A

  The present invention has been made based on the above background, and an object thereof is to provide a novel fiber for artificial hair excellent in durability.

  As a result of intensive studies to achieve the above-mentioned object, the present inventors have found that the surface of a polyester fiber having a specific fiber cross-sectional shape is provided with irregularities so that it has a practical combing property and excellent gloss. It has been determined that hair fibers can be obtained.

  Thus, according to the present invention, it is a fiber for artificial hair made of a polyester fiber, the polyester fiber has a glasses-shaped cross section, its necking degree is 2.5 to 8, and the fiber surface has irregularities. A featured artificial hair fiber is provided.

  Artificial hair as used herein refers to all or part of various products to be worn on the hair or head for the purpose of supplementing hair such as wigs, hair wigs, hair extensions, hair bands, etc. It is a constituent fiber material.

  Since the fiber for artificial hair of the present invention has irregularities of a specific size formed on the surface of a polyester fiber having a specific fiber cross-sectional shape, it feels very similar to human hair and has good combability It has durability that can withstand practical use. Therefore, it is extremely useful as various artificial hair products to be worn on the hair part or the head for the purpose of supplementing hair such as wigs, hair wigs, extensions, hair bands, or the like.

  The polyester constituting the fiber for artificial hair of the present invention is a polyester having terephthalic acid as the main bifunctional carboxylic acid and ethylene glycol, 1,3-propanediol or 1,4-butanediol as the main glycol component, specifically For these, polyethylene terephthalate, polypropylene terephthalate or polybutylene terephthalate is preferable. These polyesters have a copolymer component of 15 mol% or less, preferably 10 mol% or less, particularly preferably 5 mol% or less, based on the total acid component, within a range not impairing the object of the present invention. It may be copolymerized. The copolymer components preferably used include 2,6-naphthalenedicarboxylic acid, 4,4′-dicarboxyphenoxymethane, isophthalic acid, phosphoric acid, phosphonic acid and other acid components, diethylene glycol, bisphenol-A ethylene oxide (EO) ) Diol components such as adducts can be exemplified. Among these, phosphorus compounds such as phosphoric acid and phosphonic acid are preferable from the viewpoint of flame retardancy. Further, as long as the amount is small, a trifunctional compound such as trimesic acid, trimellitic acid, boric acid, glycerin, trimethylolpropane and the like may be copolymerized.

  These polyesters include other thermoplastic synthetic resins for modification purposes, such as polyamides such as nylon 6 and nylon 6 and 6, polyolefins such as polyethylene and polypropylene, polytetrafluoroethylene, polyvinylidene fluoride, ethylene Fluorine-containing polymers such as tetrafluoroethylene copolymer may be mixed in the range of 0.5 to 50% by weight.

  Further, the above polyester may contain a known ultraviolet absorber for the purpose of preventing discoloration of the artificial hair being used. As an ultraviolet absorber preferably used, for example, 2,2-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazol-2-yl) phenol, 2- [ 2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, 2- (5-methyl-2-hydroxyphenyl) benzotriazole, 2- [3,5-bis (2 , 2-Dimethylpropyl) -2-hydroxyphenyl] benzotriazole, 2- (3-tertiarybutyl-5-methyl-2-hydroxyphenyl) -5-chlorobenzotriazole, 2- (3,5-tertiarybutyl) Benzotriazol such as 2-hydroxyphenyl) -5-chlorobenzotriazole, 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole UV absorber, 2-hydroxy-4- (methacryloyloxyethoxy) benzophenone 30-50 mol% and methyl methacrylate 70-30 mol% random copolymer, 2,4-dihydroxybenzophenone, 2,2 ', 4 Benzophenone UV absorbers such as 4'-tetrahydroxybenzophenone, 2-hydroxy-4- (β-hydroxyethoxy) -benzophenone, bis (5-benzoyl-4-hydroxy-2-methoxyphenyl) methane, iron oxide fine particles, etc. Can be illustrated.

  Among them, bis (5-benzoyl-4-hydroxy-2-methoxyphenyl) methane, 2,2-methylenebis [4- (1,1,3,3-tetramethylbutyl) -6- (2H-benzotriazole- When 2-yl) phenol, 2- [2-hydroxy-3,5-bis (α, α-dimethylbenzyl) phenyl] -2H-benzotriazole, iron oxide fine particles, etc. are added to and mixed with molten polyester The heat resistance is favorable and high light resistance is obtained, which is preferable. In addition, a random copolymer of 2-hydroxy-4- (methacryloyloxyethoxy) benzophenone 30-50 mol% and methyl methacrylate 70-30 mol% has a high molecular weight, so there is little bleed out from the polyester fiber and stable light resistance. It is preferable because of its property. Two or more of these various ultraviolet absorbers may be used in combination.

  Moreover, in order to protect a human body from the danger by the fire in use, you may include well-known organic or inorganic flame retardants, such as phosphorus type | system | group, halogen type | system | group, and antimony trioxide, in polyester. Further, for the purpose of preventing fiber clinging and entanglement or adhesion of dust, the polyester itself may be modified, or an antistatic agent may be blended in the polyester.

  Next, the cross-sectional shape of the polyester fiber according to the present invention is a glasses type, and the degree of necking needs to be 2.5-8. When the degree of necking is less than 2.5, the combing property is poor, and the gloss is not preferable because it gives a feeling of glare. On the other hand, if it exceeds 8, the eyeglass part is liable to break and is not preferable for practical use. Here, the degree of necking is a value represented by the length of the thickest part / the length of the narrowest part in the cross-sectional shape of the glasses.

  In addition, the polyester fiber needs to have irregularities on the fiber surface, and a concave portion having a maximum length (diameter in the longitudinal direction) of the opening in the range of 2 to 20 μm is 10 to 10 per 100 square μm of the yarn surface area. It is preferable to have 30 pieces.

  When the maximum length of the opening forming the recess is less than 2 μm, the matte effect may be reduced. On the other hand, when the maximum length of the opening exceeds 20 μm, not only the roughness of the fiber surface can be seen with the naked eye but also the physical properties of the yarn are lowered, which is not preferable. In particular, a concave portion in the range of 5 to 15 μm is preferable. Further, when the number of the concave portions is less than 10 per 100 square μm, the matte effect is reduced. On the other hand, when the number is more than 30, the matte is too thin and it is not preferable. . It is particularly preferable that 10 to 20 are present.

  Here, the maximum length of the opening and the number of existence per unit area are the average values measured from photographs obtained by taking 10 fields of view of the fiber surface at a magnification of 1000 using a scanning electron microscope. Even if the number of recesses existing on the fiber surface is 10 to 30 per 100 square μm, good gloss cannot be obtained unless the maximum length of the opening is in the range of 2 to 20 μm. Even if the maximum part length is in the range of 2 to 30 μm, if the number of recesses present on the fiber surface is not in the range of 10 to 30 per 100 square μm, the gloss is undesirably distant from human hair.

  The method for forming the concave portion having such a shape on the surface of the polyester fiber is not particularly limited, and any known method such as a conventionally known blasting method or alkali weight reduction processing method can be employed. In particular, a method of forming fine pores on the fiber surface by subjecting a fiber containing a fine pore forming agent in polyester to an alkali weight reduction treatment is preferable. Fine pore forming agents include silica sol, dry silica containing aluminum oxide, dry silica with silanol groups blocked on the particle surface, alumina sol, fine alumina, ultrafine titanium oxide, fine calcium carbonate, organic sulfonic acid A compound etc. can be illustrated, The shape of a recessed part can be controlled by selecting these average particle diameters, addition amount, and alkali weight reduction process conditions suitably. Especially, when a micropore formation agent is a compound containing a metal, since the recessed part of a favorable shape can be formed by an alkali weight reduction process, it is especially preferable.

  Next, it is desirable that the single fiber fineness of the fiber for artificial hair of the present invention is in the range of 20 to 110 dtex, preferably 30 to 90 dtex from the viewpoint of expressing a natural effect. Further, the single fiber fineness is not one type, and it is also possible to mix several types of fibers such as a mixture of two single fiber finenesses of 30 dtex and 70 dtex.

  The polyester fiber according to the present invention may not be colored, but is dyed as necessary. Although a disperse dye may be used as the dye, it is preferable to use a dye having a light fastness of 5 or higher from the viewpoint of discoloration of the artificial hair being used. As a dyeing method, a known dyeing carrier agent may be used in combination, but a high-pressure dyeing method that does not require a dyeing carrier agent is more preferable. In addition, various pigments such as carbon black may be added to the polyester fiber before dyeing. In this case, not only can the dye at the time of dyeing be saved, but it is preferable because it is not necessary to dye depending on the use. .

  Since the fiber for artificial hair of the present invention described above is a polyester fiber having irregularities on the surface of a polyester fiber having a specific fiber cross-sectional shape, artificial hair very similar to human hair can be easily obtained. It became possible.

Hereinafter, the present invention will be described more specifically with reference to examples.
[Example 1]
Intrinsic viscosity (phenol and tetrachloroethane) in which 0.5% by weight of sodium benzenesulfonate-3,5-di (Mg1 / 2 carboxylic acid) was dispersed in the polymer (0.34 mol% with respect to the terephthalic acid component) (Measured in a 1: 1 mixed solvent at 25 ° C.) A 0.64 polyethylene terephthalate chip was dried at 160 ° C. under vacuum for 8 hours. A spinneret having 30 holes of spinning holes in the shape of FIG. 1 is used for the chip at 290 ° C. using an extruder-type kneader, a metering gear pump, and a spinning machine having a filtration layer made of 50 mesh glass beads and a 150 mesh wire mesh. It was further melted and discharged, and after being cooled with 40 ° C. hot water at a position 5 cm below the spinneret, a wound spinning yarn was obtained. Next, the film was stretched 4.0 times in warm water at 70 ° C., further subjected to tension heat treatment at 150 ° C., and then wound as a stretched yarn of 3000 dtex / 30 fil. N treatment (treatment at 98 ° C. for 30 minutes in a 50 g / liter aqueous solution of NaOH) was added to the obtained drawn yarn to obtain a polyester fiber having a weight loss rate of 10% by weight.

  The cross-section of the obtained polyester fiber is glasses-type and the degree of necking is 3.5, and there are twelve concave portions with a maximum opening length of 2 μm or more and 20 μm or less per 100 square μm of fiber surface area on the fiber surface. It was. The fiber strength was 3.36 cN / dtex, and the single fiber fineness was 58 dtex. This fiber was dyed using a high-pressure Smith dyeing machine with a dyeing solution shown below at a bath ratio of 20: 1 at 130 ° C. for 60 minutes, and then hydrosulfite 1.5 g / liter, caustic soda 1 g. Reductive washing was performed at 80 ° C. for 20 minutes in a bath ratio of 20: 1 in an aqueous solution containing 1 g / liter of amylazine / liter. The resulting artificial hair was planted on a net with 20,000 hairs to form a wig.

(Staining solution)
Sumikasen Brown 2.5% owf
Miketon Polyster Black 0.3% owf
Dianix Fast Yellow 1.5% owf
Dianix Fast Dark Green 1.0% owf
The obtained wig was excellent in gloss, combing and the like. I wore it for 6 months, but there was no change.

[Example 2]
Artificial hair fibers were obtained in the same manner as in Example 1 except that the distance to the lower surface of the spinneret was 3 cm. The cross-section of the obtained polyester fiber is glasses-type and the degree of necking is 5.1, and 22 concave portions having a maximum opening length of 2 μm or more and 20 μm or less exist on the surface of the fiber per 100 square μm of fiber surface area. It was. The resulting artificial hair was planted on a net with 20,000 hairs to form a wig.
The obtained wig was excellent in gloss, combing and the like. I wore it for 6 months, but there was no change.

[Comparative Example 1]
A fiber for artificial hair was obtained in the same manner as in Example 1 except that the polyethylene terephthalate chip did not contain sodium benzenesulfonate-3,5-di (carboxylate Mg1 / 2). The cross section of this fiber was a glasses type and the degree of necking was 2.7, but the fiber surface was flat and no recess was observed. The wig was the same as in Example 1, but it had a plastic-like gloss and could not be used as a wig.

[Comparative Example 2]
Artificial hair was obtained in the same manner as in Example 1 except that the nozzle shape was round. The cross-sectional shape of the obtained polyester fiber was round, and 15 concave portions having a maximum opening length of 2 μm or more and 20 μm or less were present on the fiber surface per 100 square μm of fiber surface area. The resulting artificial hair was planted on a net with 20,000 hairs to form a wig.
The obtained wig was not combable and could not withstand practical use.

  The fiber for artificial hair of the present invention can be used very suitably for various artificial hair-related products to be attached to the hair part or head such as wigs, hair wigs, extensions and hair bands.

Claims (3)

  A fiber for artificial hair comprising a polyester fiber, wherein the cross-section of the polyester fiber is glasses-shaped, the degree of necking is 2.5 to 8, and the fiber surface has irregularities .   The fiber for artificial hair according to claim 1, wherein 10 to 30 concave portions having a maximum opening length of 2 to 20 µm per 100 square µm are formed on the surface of the polyester fiber.   The fiber for artificial hair according to claim 1 or 2, wherein the single fiber fineness of the polyester fiber is 20 to 110 dtex.