Patent Application
20240426028
The present invention relates to a fiber for artificial hair, a fiber bundle for artificial hair, a hair decoration product, and the like.
Vinyl chloride polymer fibers obtained by spinning a vinyl chloride polymer are excellent in flexibility, and thus are often used as fibers for artificial hair constituting hair decoration products. However, since the vinyl chloride polymer has a large specific gravity, the vinyl chloride polymer fibers are not suitable for styles requiring volume in artificial hair use applications. In order to reduce the specific gravity of the vinyl chloride polymer fibers, a means for blending an aromatic vinyl polymer having a smaller specific gravity than that of the vinyl chloride polymer has been proposed (see, for example, Patent Literatures 1 and 2 below).
The present inventors have conceived of improving voluminousness by subjecting a fiber for artificial hair to a gear processing treatment so as to crimp the fiber for artificial hair when a hair decoration product is obtained using the fiber for artificial hair. However, in the case of using a fiber for artificial hair containing an aromatic vinyl polymer, there is a problem in that voluminousness may not be sufficiently improved, and styles that can be created are limited.
An aspect of the present invention provides a fiber for artificial hair with which artificial hair excellent in voluminousness (specific volume) can be obtained by subjecting the fiber to a gear processing treatment. Another aspect of the present invention provides a fiber bundle for artificial hair using the fiber for artificial hair. Still another aspect of the present invention provides a hair decoration product using the fiber bundle for artificial hair.
The present invention relates to the following [1] to [9], and the like, in some aspects.
According to an aspect of the present invention, it is possible to provide a fiber for artificial hair with which artificial hair excellent in voluminousness (specific volume) can be obtained by subjecting the fiber to a gear processing treatment. According to another aspect of the present invention, it is possible to provide a fiber bundle for artificial hair using the fiber for artificial hair. According to still another aspect of the present invention, it is possible to provide a hair decoration product using the fiber bundle for artificial hair. According to still another aspect of the present invention, it is possible to provide an application of a fiber to artificial hair or its production. According to still another aspect of the present invention, it is possible to provide an application of a fiber to a hair decoration product or its production.
Hereinafter, embodiments for carrying out the present invention will be described in detail. Note that, the present invention is not limited to embodiments which will be described below.
In the numerical ranges that are described stepwise in the present specification, the upper limit value or the lower limit value of the numerical range of a certain stage can be arbitrarily combined with the upper limit value or the lower limit value of the numerical range of another stage. In the numerical ranges that are described in the present specification, the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in Examples. Materials listed as examples in the present specification can be used singly or in combinations of two or more kinds, unless otherwise specifically indicated. In a case where a plurality of substances corresponding to each component in a composition is present, unless otherwise specifically indicated, the content of each component in the composition means the total amount of the plurality of substances present in the composition. The term “(meth)acrylonitrile” means at least one of acrylonitrile and methacrylonitrile corresponding thereto. The same also applies to other similar expressions such as “(meth)acrylic acid”.
A fiber for artificial hair of the present embodiment contains a vinyl chloride polymer and an aromatic vinyl polymer (excluding a polymer corresponding to the vinyl chloride polymer). A heat shrinkage rate at 100° C. of the fiber for artificial hair of the present embodiment is 7% or more. The fiber for artificial hair of the present embodiment is configured by a resin composition (fibrous resin composition) containing a vinyl chloride polymer and an aromatic vinyl polymer and having a heat shrinkage rate at 100° C. of 7% or more. The resin composition of the present embodiment is a resin composition for artificial hair, the resin composition containing a vinyl chloride polymer and an aromatic vinyl polymer and having a heat shrinkage rate at 100° C. of 7% or more.
According to the fiber for artificial hair of the present embodiment, artificial hair excellent in voluminousness (specific volume) can be obtained by subjecting the fiber for artificial hair to a gear processing treatment, and for example, in the evaluation method described in Examples below, a specific volume of more than 7.0 cc/g can be obtained by subjecting the fiber for artificial hair to a gear processing treatment (treatment in the fiber length direction, depth of the groove of the gear waveform: 2.5 mm, gear pitch: 2.5 mm, surface temperature: 90° C., processing rate: 1.0 m/min). It is speculated that, when the heat shrinkage rate of the fiber containing a vinyl chloride polymer and an aromatic vinyl polymer is high, a crimp of the fiber is easily generated due to the surface temperature of the gear when the fiber is subjected to the gear processing treatment, and thus voluminousness is improved. However, the factors that improve voluminousness are not limited to these factors.
The gear processing treatment is a treatment of passing the fiber (fiber bundle or the like) between two meshing high-temperature gears to perform crimping. In the gear processing treatment for the fiber for artificial hair of the present embodiment, the material of the gear, the gear waveform, the fraction of the gear, and the like are not particularly limited. The wave shape of the crimp can change depending on the fiber material, the fineness, pressure conditions between the gears, and the like, but in the present embodiment, the wave shape of the crimp can be controlled by the depth of the groove of the gear waveform, the surface temperature of the gear, the processing rate, and the like. There are no particular restrictions on these processing conditions, but the depth of the groove of the gear waveform may be 0.2 to 6 mm or 0.5 to 5 mm, the surface temperature of the gear may be 50 to 110° C. or 60 to 100° C., and the processing rate may be 0.5 to 10 m/min or 1.0 to 8.0 m/min.
In a conventional fiber for artificial hair, when the fiber is crimped, combability may be deteriorated. On the other hand, according to an embodiment of the fiber for artificial hair of the present embodiment, it is possible to obtain excellent combability while obtaining excellent voluminousness, and for example, in the evaluation method described in Examples below, the resistive force can be reduced to 300 gf or less (for example, 250 gf or less).
It may be demanded for the fiber for artificial hair to suppress the breakage of the fiber (yarn breakage) at the time of performing melt-spinning or the like and to be excellent in spinnability. On the other hand, according to an embodiment of the fiber for artificial hair of the present embodiment, it is possible to obtain excellent spinnability, and for example, in the evaluation method described in Examples below, the yarn breakage can be suppressed to 3 times or less.
The heat shrinkage rate at 100° C. of the fiber for artificial hair of the present embodiment is 7% or more from the viewpoint of obtaining excellent voluminousness. The heat shrinkage rate may be 8% or more, 9% or more, 10% or more, 11% or more, 12% or more, 15% or more, 18% or more, 19% or more, 20% or more, 22% or more, 23% or more, 25% or more, or 28% or more, from the viewpoint of easily obtaining excellent voluminousness. The heat shrinkage rate may be 40% or less, 35% or less, 30% or less, 28% or less, 25% or less, 23% or less, 22% or less, 20% or less, 19% or less, 18% or less, 15% or less, 12% or less, 11% or less, 10% or less, 9% or less, or 8% or less, from the viewpoint of easily obtaining excellent combability. From these viewpoints, the heat shrinkage rate may be 7 to 40%, 7 to 30%, 8 to 30%, 8 to 28%, 10 to 28%, 12 to 28%, 15 to 28%, 20 to 28%, 22 to 28%, 7 to 25%, 8 to 25%, 8 to 22%, 8 to 20%, 8 to 15%, 10 to 25%, 15 to 25%, or 20 to 25%.
The heat shrinkage rate at 100° C. of the fiber for artificial hair of the present embodiment can be measured by the method described in Examples below. The heat shrinkage rate can be adjusted by the heating temperature of a heating treatment after spinning (for example, a heating treatment after a stretching treatment) at the time of obtaining a fiber for artificial hair; the type or content of the monomer unit of the vinyl chloride polymer; the type or content of the monomer unit of the aromatic vinyl polymer; and the like. The present inventors have found that the heat shrinkage rate is easily increased by lowering the heating temperature of the heating treatment, and the heat shrinkage rate of the fiber for artificial hair obtained at a heating temperature of 120° C. as shown in Examples of Patent Literatures 1 and 2 is not sufficiently high (see Comparative Examples below), and from these findings, found that a fiber for artificial hair having a large heat shrinkage rate is easily obtained at a heating temperature of lower than 120° C. (for example, 110° C. or lower).
The fiber for artificial hair of the present embodiment can be used for obtaining artificial hair. The fiber for artificial hair of the present embodiment may be a fiber obtained after a stretching treatment, or may be a non-stretched fiber.
The single fiber fineness of the fiber for artificial hair of the present embodiment may be in the following range. The single fiber fineness may be 10 dtex or more, 20 dtex or more, 30 dtex or more, 40 dtex or more, 50 dtex or more, or 60 dtex or more. The single fiber fineness may be 100 dtex or less, 90 dtex or less, 80 dtex or less, 70 dtex or less, or 60 dtex or less. From these viewpoints, the single fiber fineness may be 10 to 100 dtex, 30 to 90 dtex, or 50 to 70 dtex.
The fiber for artificial hair of the present embodiment contains a vinyl chloride polymer (for example, a vinyl chloride-based resin). The vinyl chloride polymer is a polymer having vinyl chloride as a monomer unit (a polymer having a structural unit derived from vinyl chloride). The vinyl chloride polymer may be a homopolymer of vinyl chloride, or may be a copolymer of vinyl chloride. The copolymer of vinyl chloride is a polymer of vinyl chloride and another compound (compound other than vinyl chloride).
Examples of the copolymer of vinyl chloride include copolymers of vinyl chloride and vinyl esters such as a vinyl chloride-vinyl acetate copolymer and a vinyl chloride-vinyl propionate copolymer; copolymers of vinyl chloride and acrylic acid esters such as a vinyl chloride-butyl acrylate copolymer and a vinyl chloride-2-ethylhexyl acrylate copolymer; copolymers of vinyl chloride and olefins such as a vinyl chloride-ethylene copolymer and a vinyl chloride-propylene copolymer; and a vinyl chloride-acrylonitrile copolymer.
From the viewpoint of easily obtaining excellent voluminousness, combability, and spinnability, the vinyl chloride polymer may include at least one selected from the group consisting of a homopolymer of vinyl chloride, a vinyl chloride-ethylene copolymer, and a vinyl chloride-vinyl acetate copolymer, and may include a homopolymer of vinyl chloride.
The vinyl chloride polymer can be produced by emulsion polymerization, bulk polymerization, suspension polymerization, or the like. The vinyl chloride polymer may be a polymer produced by suspension polymerization from the viewpoint of the initial colorability of the fiber, or the like.
The content of the vinyl chloride polymer is more than 0% by mass and less than 100% by mass on the basis of the total mass of the fiber for artificial hair or the total amount of the vinyl chloride polymer and the aromatic vinyl polymer, and may be in the following range. The content of the vinyl chloride polymer may be 98% by mass or less, 96% by mass or less, 95% by mass or less, less than 95% by mass, 90% by mass or less, 85% by mass or less, 83% by mass or less, 80% by mass or less, 75% by mass or less, 70% by mass or less, or 65% by mass or less, from the viewpoint of easily obtaining excellent voluminousness. The content of the vinyl chloride polymer may be 40% by mass or more, 45% by mass or more, 50% by mass or more, 55% by mass or more, 60% by mass or more, 65% by mass or more, 70% by mass or more, 75% by mass or more, 80% by mass or more, 83% by mass or more, 85% by mass or more, 90% by mass or more, 95% by mass or more, more than 95% by mass, or 96% by mass or more, from the viewpoint of easily obtaining excellent combability and spinnability. From these viewpoints, the content of the vinyl chloride polymer may be 40 to 98% by mass, 50 to 96% by mass, 60 to 96% by mass, 65 to 96% by mass, 70 to 96% by mass, 60 to 95% by mass, 65 to 90% by mass, 65 to 80% by mass, or 65 to 70% by mass.
The fiber for artificial hair of the present embodiment contains an aromatic vinyl polymer (for example, an aromatic vinyl-based resin). The aromatic vinyl polymer is a polymer having an aromatic vinyl compound as a monomer unit (a polymer having a structural unit derived from an aromatic vinyl compound). Examples of the aromatic vinyl compound include a styrene-based compound, vinyltoluene, vinylnaphthalene, and vinylanthracene. From the viewpoint of easily obtaining excellent voluminousness, combability, and spinnability, the aromatic vinyl polymer may have a styrene-based compound as a monomer unit.
The styrene-based compound may include at least one selected from the group consisting of styrene and a styrene derivative. Examples of the styrene derivative include α-methylstyrene, o-methylstyrene, m-methylstyrene, p-methylstyrene, t-butylstyrene, and chlorostyrene. From the viewpoint of easily obtaining excellent voluminousness, combability, and spinnability, the styrene-based compound may include styrene.
The aromatic vinyl polymer may be a homopolymer of an aromatic vinyl compound, or may be a copolymer of an aromatic vinyl compound (for example, an aromatic vinyl-based copolymer resin). The aromatic vinyl copolymer may be a copolymer having a plurality of kinds of aromatic vinyl compounds as monomer units, or may be a copolymer having an aromatic vinyl compound and a compound different from the aromatic vinyl compound as monomer units.
Examples of the compound different from the aromatic vinyl compound include (meth)acrylonitrile, a vinyl-based compound (excluding a compound corresponding to the styrene-based compound), and maleic anhydride. Examples of the vinyl-based compound include (meth)acrylic acid; and (meth)acrylic acid esters such as methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate. The aromatic vinyl polymer may not have a (meth)acrylic acid ester as a monomer unit (may not have at least one selected from the group consisting of an acrylic acid ester and a methacrylic acid ester as a monomer unit). As the aromatic vinyl polymer, a polymer not having vinyl chloride as a monomer unit can be used, and a polymer not having a halogen-containing compound as a monomer unit may be used.
From the viewpoint of easily obtaining excellent voluminousness, combability, and spinnability, the aromatic vinyl polymer may have a styrene-based compound and (meth)acrylonitrile as monomer units (may have a monomer unit of a styrene-based compound and at least one selected from the group consisting of a monomer unit of acrylonitrile and a monomer unit of methacrylonitrile), may have styrene and (meth)acrylonitrile as monomer units (may have a monomer unit of styrene and at least one selected from the group consisting of a monomer unit of acrylonitrile and a monomer unit of methacrylonitrile), or may have styrene and acrylonitrile as monomer units.
The proportion of the monomer unit of the styrene-based compound may be in the following range on the basis of the entire aromatic vinyl polymer or on the basis of the total amount of the monomer unit of the styrene-based compound and the monomer unit of the (meth)acrylonitrile (the total amount of the monomer unit of the styrene-based compound, the monomer unit of acrylonitrile, and the monomer unit of methacrylonitrile). The proportion of the monomer unit of the styrene-based compound may be 50% by mass or more, more than 50% by mass, 60% by mass or more, more than 60% by mass, 65% by mass or more, 68% by mass or more, 69% by mass or more, more than 69% by mass, 70% by mass or more, more than 70% by mass, 74% by mass or more, 75% by mass or more, 80% by mass or more, 82% by mass or more, 85% by mass or more, more than 85% by mass, 86% by mass or more, or 90% by mass or more, from the viewpoint of easily obtaining excellent voluminousness. The proportion of the monomer unit of the styrene-based compound may be less than 100% by mass, 95% by mass or less, 90% by mass or less, 88% by mass or less, less than 88% by mass, 86% by mass or less, 85% by mass or less, less than 85% by mass, 82% by mass or less, 80% by mass or less, 75% by mass or less, 70% by mass or less, less than 70% by mass, 69% by mass or less, less than 69% by mass, or 68% by mass or less, from the viewpoint of easily obtaining excellent combability and spinnability. From these viewpoints, the proportion of the monomer unit of the styrene-based compound may be 50% by mass or more and less than 100% by mass, 60 to 95% by mass, 68 to 90% by mass, 68 to 86% by mass, 68 to 82% by mass, 68 to 75% by mass, 68 to 70% by mass, 70 to 90% by mass, 75 to 90% by mass, 82 to 90% by mass, 86 to 90% by mass, 70 to 86% by mass, 70 to 82% by mass, 70 to 75% by mass, 75 to 86% by mass, 82 to 86% by mass, 75 to 82% by mass, 50 to 82% by mass, 60 to 82% by mass, 82 to 95% by mass, 74 to 88% by mass, or 74% by mass or more and less than 88% by mass.
The proportion of the monomer unit of the (meth)acrylonitrile (the proportion of the total amount of the monomer unit of acrylonitrile and the monomer unit of methacrylonitrile) may be in the following range on the basis of the entire aromatic vinyl polymer or on the basis of the total amount of the monomer unit of the styrene-based compound and the monomer unit of the (meth)acrylonitrile (the total amount of the monomer unit of the styrene-based compound, the monomer unit of acrylonitrile, and the monomer unit of methacrylonitrile). The proportion of the monomer unit of the (meth)acrylonitrile may be more than 0% by mass, 5% by mass or more, 10% by mass or more, 12% by mass or more, more than 12% by mass, 14% by mass or more, 15% by mass or more, more than 15% by mass, 18% by mass or more, 20% by mass or more, 25% by mass or more, 30% by mass or more, more than 30% by mass, 31% by mass or more, more than 31% by mass, or 32% by mass or more, from the viewpoint of easily obtaining excellent combability and spinnability. The proportion of the monomer unit of the (meth)acrylonitrile may be 50% by mass or less, less than 50% by mass, 40% by mass or less, less than 40% by mass, 35% by mass or less, 32% by mass or less, 31% by mass or less, less than 31% by mass, 30% by mass or less, less than 30% by mass, 26% by mass or less, 25% by mass or less, 20% by mass or less, 18% by mass or less, 15% by mass or less, less than 15% by mass, 14% by mass or less, or 10% by mass or less, from the viewpoint of suppressing the color tone of the fiber for artificial hair. From these viewpoints, the proportion of the monomer unit of the (meth)acrylonitrile may be more than 0% by mass and 50% by mass or less, 5 to 40% by mass, 10 to 32% by mass, 14 to 32% by mass, 18 to 32% by mass, 25 to 32% by mass, 30 to 32% by mass, 10 to 30% by mass, 10 to 25% by mass, 10 to 18% by mass, 10 to 14% by mass, 14 to 30% by mass, 18 to 30% by mass, 25 to 30% by mass, 14 to 25% by mass, 14 to 18% by mass, 18 to 25% by mass, 18 to 50% by mass, 18 to 40% by mass, 5 to 18% by mass, 12 to 26% by mass, or more than 12% by mass and 26% by mass or less.
The combination of the proportion of the monomer unit of the styrene-based compound and the proportion of the monomer unit of the (meth)acrylonitrile is any combination, and each of the proportion of the monomer unit of the styrene-based compound and the proportion of the monomer unit of the (meth)acrylonitrile may be in each of the above ranges. For example, the aromatic vinyl polymer may be an embodiment in which the proportion of the monomer unit of the styrene-based compound is 50 to 95% by mass and the proportion of the monomer unit of the (meth)acrylonitrile is 5 to 50% by mass, may be an embodiment in which the proportion of the monomer unit of the styrene-based compound is 68 to 90% by mass and the proportion of the monomer unit of the (meth)acrylonitrile is 10 to 32% by mass, or may be an embodiment in which the proportion of the monomer unit of the styrene-based compound is 74 to 88% by mass and the proportion of the monomer unit of the (meth)acrylonitrile is 12 to 26% by mass, on the basis of the entire aromatic vinyl polymer or on the basis of the total amount of the monomer unit of the styrene-based compound and the monomer unit of the (meth)acrylonitrile (the total amount of the monomer unit of the styrene-based compound, the monomer unit of acrylonitrile, and the monomer unit of methacrylonitrile).
The total amount of the monomer unit of the styrene-based compound and the monomer unit of the (meth)acrylonitrile in the aromatic vinyl polymer (the total amount of the monomer unit of the styrene-based compound, the monomer unit of acrylonitrile, and the monomer unit of methacrylonitrile) may be 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, 92% by mass or more, 95% by mass or more, 96% by mass or more, 98% by mass or more, 99% by mass or more, 99.5% by mass or more, or substantially 100% by mass, on the basis of the entire aromatic vinyl polymer, from the viewpoint of easily obtaining excellent voluminousness, combability, and spinnability.
The content of the aromatic vinyl polymer is more than 0% by mass and less than 100% by mass on the basis of the total mass of the fiber for artificial hair or the total amount of the vinyl chloride polymer and the aromatic vinyl polymer, and may be in the following range. The content of the aromatic vinyl polymer may be 2% by mass or more, 4% by mass or more, 5% by mass or more, more than 5% by mass, 10% by mass or more, 15% by mass or more, 17% by mass or more, 20% by mass or more, 25% by mass or more, 30% by mass or more, or 35% by mass or more, from the viewpoint of easily obtaining excellent voluminousness. The content of the aromatic vinyl polymer may be 60% by mass or less, 55% by mass or less, 50% by mass or less, 45% by mass or less, 40% by mass or less, 35% by mass or less, 30% by mass or less, 25% by mass or less, 20% by mass or less, 17% by mass or less, 15% by mass or less, 10% by mass or less, 5% by mass or less, less than 5% by mass, or 4% by mass or less, from the viewpoint of easily obtaining excellent combability and spinnability. From these viewpoints, the content of the aromatic vinyl polymer may be 2 to 60% by mass, 4 to 50% by mass, 4 to 40% by mass, 4 to 35% by mass, 4 to 30% by mass, 5 to 40% by mass, 10 to 35% by mass, 20 to 35% by mass, or 30 to 35% by mass.
The combination of the content of the vinyl chloride polymer and the content of the aromatic vinyl polymer is any combination, and each of the content of the vinyl chloride polymer and the content of the aromatic vinyl polymer may be in each of the above ranges. For example, the fiber for artificial hair of the present embodiment may be an embodiment in which the content of the vinyl chloride polymer is 40 to 98% by mass and the content of the aromatic vinyl polymer is 2 to 60% by mass, may be an embodiment in which the content of the vinyl chloride polymer is 60 to 95% by mass and the content of the aromatic vinyl polymer is 5 to 40% by mass, or may be an embodiment in which the content of the vinyl chloride polymer is 68 to 90% by mass and the content of the aromatic vinyl polymer is 10 to 32% by mass, on the basis of the total mass of the fiber for artificial hair or on the basis of the total amount of the vinyl chloride polymer and the aromatic vinyl polymer.
The total amount of the vinyl chloride polymer and the aromatic vinyl polymer may be 50% by mass or more, 60% by mass or more, 70% by mass or more, 80% by mass or more, 90% by mass or more, 92% by mass or more, 95% by mass or more, 96% by mass or more, 98% by mass or more, 99% by mass or more, 99.5% by mass or more, or substantially 100% by mass, on the basis of the total mass of the fiber for artificial hair.
The fiber for artificial hair of the present embodiment may contain a component other than the vinyl chloride polymer and the aromatic vinyl polymer. Examples of such component include polymers other than the vinyl chloride polymer and the aromatic vinyl polymer (such as polyolefin such as polypropylene; polyethylene terephthalate; and polymers of a (meth)acrylic acid compound such as (meth)acrylic acid or (meth)acrylic acid ester), an antistatic agent, a heat stabilizer, a lubricant, a processing aid, a plasticizer, a reinforcing agent, an ultraviolet absorber, an antioxidant, a filler, a flame retardant, a pigment, an initial coloration-improving agent, an electrical conductivity-imparting agent, and a perfume. The fiber for artificial hair of the present embodiment may not contain at least one of these components, or may not contain at least one selected from the group consisting of polyolefin (such as polypropylene), polyethylene terephthalate, and polymers of a (meth)acrylic acid compound (such as (meth)acrylic acid or (meth)acrylic acid ester).
Examples of the antistatic agent include cationic, anionic, and amphoteric antistatic agents. The content (blended amount) of the antistatic agent may be 0.01 to 1 part by mass with respect to 100 parts by mass of the total of the vinyl chloride polymer and the aromatic vinyl polymer or 100 parts by mass of the fiber for artificial hair (fibrous resin composition).
The heat stabilizer can be used for adjusting thermal decomposition at the time of molding, long-run workability, the color tone of filament, or the like. Examples of the heat stabilizer include a Ca—Zn-based heat stabilizer, a hydrotalcite-based heat stabilizer, a tin-based heat stabilizer, an epoxy-based heat stabilizer, and a β-diketone-based heat stabilizer. The content (blended amount) of the heat stabilizer may be 0.1 to 5.0 parts by mass with respect to 100 parts by mass of the total of the vinyl chloride polymer and the aromatic vinyl polymer or 100 parts by mass of the fiber for artificial hair (fibrous resin composition).
Examples of the Ca—Zn-based heat stabilizer include zinc stearate, calcium stearate, zinc 12-hydroxystearate, and calcium 12-hydroxystearate. Examples of the hydrotalcite-based heat stabilizer include a hydrotalcite compound. Examples of the hydrotalcite compound include a complex salt compound composed of magnesium and/or an alkali metal with aluminum; a complex salt compound composed of zinc, magnesium, and aluminum; and a compound obtained by dehydrating crystal water. Examples of the tin-based heat stabilizer include mercapto tin-based heat stabilizers such as dimethyltin mercapto, dimethyltin mercaptide, dibutyltin mercapto, dioctyltin mercapto, a dioctyltin mercapto polymer, and dioctyltin mercapto acetate; maleate tin-based heat stabilizers such as dimethyltin maleate, dibutyltin maleate, dioctyltin maleate, and a dioctyltin maleate polymer; and laurate tin-based heat stabilizers such as dimethyltin laurate, dibutyltin laurate, and dioctyltin laurate. Examples of the epoxy-based heat stabilizer include epoxidized soybean oil and epoxidized linseed oil. Examples of the β-diketone-based heat stabilizer include stearoyl benzoyl methane (SBM) and dibenzoyl methane (DBM).
The lubricant can be used for reducing friction with a metal surface of a processing machine and a friction between resins and enhancing flowability to adjust processability. Examples of the lubricant include a metal soap-based lubricant, a higher fatty acid-based lubricant, an ester-based lubricant, a higher alcohol-based lubricant, and a hydrocarbon-based lubricant. The content (blended amount) of the lubricant may be 0.2 to 5.0 parts by mass with respect to 100 parts by mass of the total of the vinyl chloride polymer and the aromatic vinyl polymer or 100 parts by mass of the fiber for artificial hair (fibrous resin composition).
Examples of the metal soap-based lubricant include metal soaps (for example, stearate, laurate, palmitate, and oleate of Na, Mg, Al, Ca, Ba, and the like). Examples of the higher fatty acid-based lubricant include saturated fatty acids such as stearic acid, palmitic acid, myristic acid, lauric acid, and capric acid; unsaturated fatty acids such as oleic acid; and mixtures thereof. Examples of the ester-based lubricant include a pentaerythritol-based lubricant, a montanic acid wax-based lubricant, and a lubricant composed of an alcohol and a fatty acid. Examples of the pentaerythritol-based lubricant include monoesters, diesters, triesters, or tetraesters of a higher fatty acid with pentaerythritol or dipentaerythritol; and mixtures thereof. Examples of the montanic acid wax-based lubricant include esters of montanic acids with higher alcohols (such as stearyl alcohol, palmityl alcohol, myristyl alcohol, lauryl alcohol, and oleyl alcohol). Examples of the higher alcohol-based lubricant include stearyl alcohol, palmityl alcohol, myristyl alcohol, lauryl alcohol, and oleyl alcohol. Examples of the hydrocarbon-based lubricant include polyethylene wax and polypropylene wax.
The content of the vinyl chloride-based acrylic graft copolymer in the fiber for artificial hair of the present embodiment may be 1 part by mass or less, less than 1 part by mass, 0.1 parts by mass or less, 0.01 parts by mass or less, or substantially 0 parts by mass, with respect to 100 parts by mass of the total of the vinyl chloride polymer and the vinyl polymer (for example, the aromatic vinyl polymer).
A method for producing a fiber for artificial hair of the present embodiment includes a heating step of heat-treating a base fiber containing a vinyl chloride polymer and an aromatic vinyl polymer to obtain a fiber for artificial hair. The base fiber may be a fiber obtained in a stretching step described below. In the heating step, for example, the base fiber may be heat-treated in an air atmosphere using a heat treatment machine until the fiber total length shrinks to 0.5 to 0.9 times the length before the treatment.
The glass transition temperature (Tg) of the base fiber may be in the following range. The glass transition temperature may be 80° C. or higher, 85° C. or higher, 90° C. or higher, 94° C. or higher, 95° C. or higher, 100° C. or higher, 104° C. or higher, 105° C. or higher, 108° C. or higher, 109° C. or higher, 110° C. or higher, 115° C. or higher, 116° C. or higher, 120° C. or higher, or 124° C. or higher, from the viewpoint of easily obtaining excellent combability. The glass transition temperature may be 150° C. or lower, 140° C. or lower, 130° C. or lower, 125° C. or lower, 124° C. or lower, 120° C. or lower, 116° C. or lower, 115° C. or lower, 110° C. or lower, 109° C. or lower, 108° C. or lower, 105° C. or lower, 104° C. or lower, or 100° C. or lower, from the viewpoint of easily obtaining excellent voluminousness. The glass transition temperature may be 95° C. or lower or 94° C. or lower. From these viewpoints, the glass transition temperature may be 80 to 150° C., 94 to 124° C., or 100 to 115° C. The glass transition temperature can be measured by the method described in Examples below.
The heating temperature in the heating step may be lower than 120° C., 115° C. or lower, 110° C. or lower, or 105° C. or lower. The heating temperature in the heating step may be 80° C. or higher, 90° C. or higher, 100° C. or higher, 105° C. or higher, or 110° C. or higher. From these viewpoints, the heating temperature in the heating step may be 80° C. or higher and lower than 120° C., 90 to 115° C., or 100 to 110° C.
In the method for producing a fiber for artificial hair of the present embodiment, a fiber for artificial hair having a large heat shrinkage rate at 100° C. is easily obtained at a heating temperature of lower than 120° C. (for example, 110° C. or lower). For example, in a case where the glass transition temperature of the base fiber is low (for example, the glass transition temperature is lower than 120° C.) and a temperature difference between the glass transition temperature and the temperature of 100° C. of the heat shrinkage rate is small, when the heating temperature is lower than 120° C., a fiber for artificial hair having a large heat shrinkage rate is easily obtained. Furthermore, even in a case where the glass transition temperature of the base fiber is high (for example, the glass transition temperature is 120° C. or higher) and a temperature difference between the glass transition temperature and the temperature of 100° C. of the heat shrinkage rate is large, when the heating temperature is lower than 120° C., a fiber for artificial hair having a large heat shrinkage rate is easily obtained.
The method for producing a fiber for artificial hair of the present embodiment may include a melt-kneading step of melt-kneading the vinyl chloride polymer and the aromatic vinyl polymer. In the melt-kneading step, for example, the vinyl chloride polymer and the aromatic vinyl polymer are stirred and mixed to obtain a powder compound, and then the powder compound is melt-kneaded to obtain a pellet compound. When the vinyl chloride polymer and the aromatic vinyl polymer are stirred and mixed, an antistatic agent, a heat stabilizer, a lubricant, or the like may be mixed as appropriate. In the stirring and mixing for obtaining a powder compound, a Henschel mixer, a supermixer, a ribbon blender, or the like can be used. In the melt-kneading for obtaining a pellet compound, a single screw extruder, a counter-rotating twin screw extruder, a conical twin screw extruder, a corotating twin screw extruder, a cokneader, a planetary gear extruder, a roll kneader, or the like can be used.
The method for producing a fiber for artificial hair of the present embodiment may include a melt-spinning step of melt-spinning a resin composition (the pellet compound obtained in the melt-kneading step) containing the vinyl chloride polymer and the aromatic vinyl polymer, after the melt-kneading step. In the melt-spinning step, for example, the resin composition is extruded by using a metallic nozzle having a plurality of nozzle holes under the conditions of a cylinder temperature of 140 to 190° C. and a nozzle temperature of 180±15° C. to perform melt-spinning. In the extrusion, a single screw extruder, a counter-rotating twin screw extruder, a conical twin screw extruder, or the like may be used, and a single screw extruder having a bore diameter of 30 to 85 mmϕ or a conical extruder having a bore diameter of 30 to 50 mmϕ may be used.
The method for producing a fiber for artificial hair of the present embodiment may include a winding step of winding up the fiber obtained in the melt-spinning step, after the melt-spinning step. In the winding step, the fiber obtained in the melt-spinning step may be introduced into a heating cylinder (heating cylinder temperature: about 250° C.), instantaneously heat-treated, and then wound by a drawing machine. During winding, the drawing speed may be adjusted so that the single fiber fineness of the fiber is 150 to 206 dtex.
The method for producing a fiber for artificial hair of the present embodiment may include a stretching step of subjecting the fiber (non-stretched fiber) to a stretching treatment to obtain a base fiber (base fiber to be heat-treated in the heating step), after the winding step. In the stretching step, for example, the non-stretched fiber may be stretched 2 to 4 times using a stretching machine (in an air atmosphere, 90 to 120° C.).
A fiber bundle for artificial hair of the present embodiment has the fiber for artificial hair of the present embodiment. The fiber bundle for artificial hair of the present embodiment may be an embodiment having a plurality of fibers for artificial hair of the present embodiment. An embodiment of the fiber bundle for artificial hair of the present embodiment may be a fiber bundle composed of the fiber for artificial hair of the present embodiment. Another embodiment of the fiber bundle for artificial hair of the present embodiment may further have, in addition to the fiber for artificial hair of the present embodiment, a fiber different from this fiber for artificial hair (a fiber for artificial hair; a fiber not corresponding to the fiber for artificial hair of the present embodiment), that is, may have the fiber for artificial hair of the present embodiment and a fiber different from this fiber for artificial hair.
By using the fiber for artificial hair of the present embodiment and the fiber different from this fiber for artificial hair in combination, other desired properties can be obtained while obtaining excellent voluminousness. The constituent material for the fiber different from the fiber for artificial hair of the present embodiment may be a fiber not containing a vinyl chloride polymer and an aromatic vinyl polymer, a fiber containing one of a vinyl chloride polymer and an aromatic vinyl polymer, or a fiber having a heat shrinkage rate at 100° C. of less than 7%. Examples of the constituent material for the fiber different from the fiber for artificial hair of the present embodiment include polyolefin such as polypropylene; polyethylene terephthalate; and polymers of a (meth)acrylic acid compound such as (meth)acrylic acid or (meth)acrylic acid ester.
The fiber for artificial hair and the fiber bundle for artificial hair of the present embodiment can be used in a hair decoration product of the present embodiment. The hair decoration product of the present embodiment has the fiber for artificial hair of the present embodiment and may have the fiber bundle for artificial hair of the present embodiment. As the hair decoration product, wigs and the like are exemplified. The fiber for artificial hair and the fiber bundle for artificial hair in the hair decoration product of the present embodiment may be in any state before or after the gear processing treatment for crimping the fiber for artificial hair. An artificial hair of the present embodiment can be obtained by subjecting the fiber for artificial hair of the present embodiment to a gear processing treatment.
Hereinafter, specific embodiments of the present invention will be described in more detail by means of Examples and Comparative Examples, but the present invention is not limited only to these Examples.
A resin composition composed of 70 parts by mass of a vinyl chloride polymer (a vinyl chloride-based resin, a homopolymer of vinyl chloride, manufactured by TAIYO VINYL CORPORATION, trade name: TH-1000), 30 parts by mass of an aromatic vinyl polymer (an aromatic vinyl-based copolymer resin, manufactured by Denka Company Limited, trade name: GR-AT-6S) having 68% by mass of a styrene monomer unit and 32% by mass of an acrylonitrile monomer unit, 0.5 parts by mass of an antistatic agent (manufactured by NOF CORPORATION, trade name: NEW ELEGAN ASK), 3 parts by mass of a hydrotalcite-based complex salt compound (manufactured by Nissan Chemical Corporation, trade name: CP-410A), 0.5 parts by mass of epoxidized soybean oil (manufactured by Asahi Denka Co., Ltd., trade name: O-130P), and 0.8 parts by mass of an ester-based lubricant (manufactured by Riken Vitamin Co., Ltd., trade name: EW-100) was prepared. Compounding was performed using this resin composition with an extruder having a diameter (bore diameter) of 40 mm at a cylinder temperature of 130 to 170° C. to produce a pellet. Next, the above-described pellet was melt-spun by an extruder having a diameter of 30 mm at an extrusion rate of 10 kg/hr at a cylinder temperature of 140 to 190° C. and at a nozzle temperature of 180° C. by using a nozzle having a nozzle cross-sectional area of 0.06 mm2, having a round shape, and having the number of holes of 120. Thereafter, heat-treating was performed by a heating cylinder (250° C.) installed at a position of 4.5 m directly below the nozzle for 1.0 second, thereby obtaining Fiber A (non-stretched fiber) with 150 dtex.
As the glass transition temperature (Tg) of Fiber A described above, the peak top temperature of the loss tangent (tan δ) in dynamic viscoelasticity measurement was measured. Specifically, using a dynamic viscoelasticity measurement device (manufactured by SII NanoTechnology Inc., DMS6100), the loss tangent (tan δ) of the fiber bundle of 40 Fibers A in a range of 25 to 170° C. was measured at a temperature increase rate of 4° C./min, a frequency of 1 Hz, and a distance between chucks of 3 mm, and the peak top temperature was measured. The glass transition temperature of Fiber A of Example 1 was 124° C.
Next, Fiber A was stretched 3 times in an air atmosphere at 100° C. to obtain Fiber B.
Next, Fiber B was heat-treated in an air atmosphere at a heating temperature (annealing temperature) of 110° C. until the fiber total length shrunk to 0.75 times the length before the treatment, thereby obtaining a fiber for artificial hair with 60 dtex.
A fiber for artificial hair with 60 dtex was obtained in the same manner as in Example 1, except that the content of the vinyl chloride polymer, the content of the aromatic vinyl polymer, the proportion of the monomer unit in the aromatic vinyl polymer, and the heating temperature (annealing temperature) of the heating treatment after the stretching treatment were changed to numerical values of Table 1 and Table 2. As the aromatic vinyl polymer different from that in Example 1, the following aromatic vinyl polymer was used. The measurement results of the glass transition temperature of Fiber A are shown in Table 1 and Table 2.
First, the above-described fiber for artificial hair was cut into a length of 100 mm to obtain fiber pieces. Next, the fiber pieces were heated for 10 minutes in an oven set at 100° C., and then the length of the fiber pieces was measured. The heat shrinkage rate was determined according to the following formula. The results are shown in Table 1 and Table 2.
As for the above-described fibers for artificial hair, spinnability, voluminousness, and combability (combing resistive force) were evaluated according to the following evaluation methods and criteria. The results are shown in Table 1 and Table 2. In Examples, it is confirmed that satisfactory results are obtained in all evaluation items.
As for spinnability, the occurrence status of the yarn breakage per an hour during melt-spinning for obtaining Fiber A (non-stretched fiber) in the production of the above-described fiber for artificial hair was visually observed. The spinnability was evaluated according to the following criteria.
The voluminousness was evaluated by the following procedure. First, the fiber bundle of the above-described fibers for artificial hair (the number of fibers: 12000, length: 10 m, mass: 800 g) was subjected to a gear processing treatment (treatment in the fiber length direction, depth of the groove of the gear waveform: 2.5 mm, gear pitch: 2.5 mm, surface temperature: 90° C., processing rate: 1.0 m/min) to obtain a fiber for evaluation, and then this fiber for evaluation was cut into a length of 100 mm to obtain fiber pieces. Next, the fiber pieces were filled in a 56 cc container (100 mm×14 mm×40 mm) until the container became full. The filled fiber pieces were taken out and then the mass of the fiber pieces was measured. Then, the specific volume was calculated by formula “Volume (cc) of the container/Mass (g) of the fiber pieces=Specific volume (cc/g)”. The value of the specific volume was calculated by performing round off to one decimal place. A case where the specific volume was more than 7.0 cc/g was determined as good.
The combability was evaluated by the following procedure. First, the fiber bundle of the above-described fiber for artificial hair (the number of fibers: 12000, length: 10 m, mass: 800 g) was subjected to a gear processing treatment (treatment in the fiber length direction, depth of the groove of the gear waveform: 2.5 mm, gear pitch: 2.5 mm, surface temperature: 90° C., processing rate: 1.0 m/min) to obtain a fiber bundle of fibers for evaluation. This fiber bundle was adjusted to have a length of 30 cm and a mass of 20 g, and then the resistive force [unit: gf] when the fiber bundle was passed through a comb at a moving speed of 10 mm/sec and a moving distance of 100 mm was measured by a static/dynamic friction measuring machine (manufactured by Trinity-Lab Inc., trade name “TL201Tt”). It was determined that the smaller the resistive force, the better the combability.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2021-134637 | Aug 2021 | JP | national |
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/JP2022/027264 | 7/11/2022 | WO |
