Resin composition for easily dyeable synthetic fibers, and synthetic fibers easily dyeable with acid dyes

Abstract

One or more embodiments of the present invention relate to a resin composition which contains at least a polymer (A) and a polymer (B), wherein: the polymer (A) contains one or more monomers that are selected from the group consisting of acrylonitrile, vinyl halides and vinylidene halides; the polymer (B) dissolves in benzyl alcohol; and from 70 parts by mass to 92.5 parts by mass of the polymer (A) and from 7.5 parts by mass to 30 parts by mass of the polymer (B) are contained if the total amount of the polymer (A) and the polymer (B) is taken as 100 parts by mass. The present invention provides a synthetic fiber which is easily dyeable with an acidic dye without requiring use of a special facility or heating to high temperatures.

Description

[Technical Field]

[0001] The present invention relates to a resin composition that can be easily dyed with dyes, particularly acid dyes, a dyeing method thereof, synthetic fibers using the same, a method for producing synthetic fibers, and head accessories containing synthetic fibers. [Background technology]

[0002] Conventionally, fibers for artificial hair have generally been dyed to a predetermined color by fiber manufacturers or processing factories and shipped to consumers, who then use the ready-made color as is, and consumers have demanded high colorability. Patent Document 1 describes an acrylic composite fiber with enhanced colorability achieved by using cellulose acetate and a cationic dye. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 5-302213 Summary of the Invention [Problem to be solved by the invention]

[0004] In recent years, consumer color preferences have become more diverse, leading to a demand for artificial hair fibers with a wide variety of colors, and in particular, a demand for artificial hair fibers that can be easily dyed by consumers themselves. However, it has been difficult to dye synthetic fibers to a desired color sufficiently even when commercially available human hair dyes (acid dyes) are applied to them. In addition, dyeing artificial hair to a desired color requires special equipment and heating at high temperatures. Therefore, a demand exists for artificial hair fibers that can be easily dyed using commercially available human hair dyes without the need for these.

[0005] Therefore, in order to solve the above-mentioned conventional problems, the present invention provides a resin composition that can be easily dyed using a dyeing agent containing an acid dye without requiring special equipment or high-temperature heating, a dyeing method thereof, synthetic fibers using the same, a method for producing synthetic fibers, and headwear products containing synthetic fibers. [Means for solving the problem]

[0006] In one or more embodiments, the present invention relates to a resin composition comprising a polymer (A) and a polymer (B), wherein the polymer (A) is a polymer containing one or more monomers selected from the group consisting of acrylonitrile, vinyl halide, and vinylidene halide, and the polymer (B) is a polymer that is soluble in benzyl alcohol, and wherein the resin composition comprises 70 parts by mass or more and 92.5 parts by mass or less of the polymer (A) and 7.5 parts by mass or more and 30 parts by mass or less of the polymer (B), where the total amount of the polymer (A) and the polymer (B) is 100 parts by mass.

[0007] In one or more embodiments, the present invention also relates to a method for dyeing a resin composition, in which the resin composition is colored by impregnating it with a dye containing a dye (C) and an alcohol.

[0008] In one or more embodiments, the present invention also relates to synthetic fibers comprised of the resin composition.

[0009] In one or more embodiments, the present invention also relates to a method for producing synthetic fibers by melt-spinning the resin composition.

[0010] In one or more embodiments, the present invention also relates to headwear products comprising the synthetic fibers. [Effects of the Invention]

[0011] According to the present invention, it is possible to provide a resin composition that can be easily dyed with a dye containing an acid dye, and a dyeing method thereof.

[0012] Furthermore, the present invention can provide a synthetic fiber that can be easily dyed with a dye containing an acid dye, a method for producing the same, and a headwear product containing the same. DETAILED DESCRIPTION OF THE INVENTION

[0013] The present inventors conducted extensive research to solve the above-mentioned problems and discovered that a resin composition containing a polymer (A) containing one or more monomer units selected from the group consisting of acrylonitrile, vinyl halide, and vinylidene halide, and a predetermined amount of a polymer (B) soluble in alcohol, particularly benzyl alcohol, and synthetic fibers composed of the resin composition can be easily dyed with a human hair dye containing an acid dye, thereby providing synthetic fibers for artificial hair with good dyeability, leading to the completion of the present invention.In particular, the present inventors discovered that a synthetic fiber composed of a resin composition containing a polymer containing one or more monomer units selected from the group consisting of vinyl acetate, vinylpyrrolidone, acrylic esters, methacrylic esters, and styrene as the benzyl alcohol-soluble polymer (B), can be easily dyed with a human hair dye containing an acid dye, thereby providing synthetic fibers for artificial hair with good dyeability, leading to the completion of the present invention.

[0014] <Dyeing agent> The resin composition according to one or more embodiments of the present invention or synthetic fibers made from the resin composition can be dyed with a dye containing a dye (C) and an alcohol. A commonly used dye for human hair can be used as the dye. The dye (C) is not particularly limited, and examples thereof include acid dyes, basic dyes, and disperse dyes. Of these, acid dyes are preferred. An acid dye refers to a water-soluble dye having an acidic group, such as a sulfonic acid group or a carboxyl acid group, in the molecule.

[0015] Because the resin composition or synthetic fibers made from the resin composition contain a polymer (B) that dissolves in benzyl alcohol, they can be easily dyed using a human hair dye containing an acid dye. While the reason for this is unclear and remains a matter of speculation, it is believed that during the dyeing process, the polymer (B) swells due to the alcohol contained in the dye and alcohol, particularly benzyl alcohol, contained in the dye. This allows the dye (particularly the acid dye) to penetrate into the resin and remain inside the resin even after rinsing with water, making dyeing possible. For example, dyeing can be achieved by applying a human hair dye containing an acid dye to the resin composition or synthetic fibers and leaving it at room temperature (25±5°C) for a predetermined time, without the need for special equipment or high-temperature heating.

[0016] The acid dye is not particularly limited, and examples thereof include Red No. 106, Red No. 201, Red No. 227, Yellow No. 4, Yellow No. 5, Yellow No. 203, Yellow No. 403, Yellow No. 406, Blue No. 1, Orange No. 205, Purple No. 401, and Black No. 401.

[0017] The alcohol is not particularly limited, and examples thereof include ethanol, 1-propanol, 2-propanol, benzyl alcohol, 2-(benzyloxy)ethanol, 2-phenylethyl alcohol, cinnamic alcohol, phenylpropanol, phenoxyethanol, α-methylbenzyl alcohol, etc. Benzyl alcohol is particularly preferred.

[0018] The dye for human hair is not particularly limited, and various forms such as cream, gel, and foam may be used, including commercially available dyes.

[0019] Dyeing agents such as human hair dyes may contain organic solvents other than the alcohols, cationic polymers, surfactants, oily components such as silicone derivatives, thickeners such as hydroxypropyl methylcellulose, hydroxyethyl cellulose, and xanthan gum, fragrances, preservatives, antioxidants, ultraviolet absorbers, sequestering agents, propellants, and pearlizing agents, as long as the effects of the present invention are not impaired.

[0020] <Polymer (B)> Polymer (B) is not particularly limited as long as it is a polymer that dissolves in alcohol, particularly benzyl alcohol. In one or more embodiments of the present invention, "dissolvable in benzyl alcohol" means that when 0.1 g of the polymer is added to 5 mL of benzyl alcohol and stirred at room temperature (25±5°C) for 1 hour, a homogeneous, transparent solution is obtained without visual observation of solids such as turbidity. Polymer (B) is preferably a polymer containing one or more monomer units selected from the group consisting of vinyl acetate, vinylpyrrolidone, acrylic acid esters, methacrylic acid esters, styrene, etc.

[0021] The weight average molecular weight (Mw) of the polymer (B) is preferably 5,000 or more and 300,000 or less, and more preferably 10,000 or more and 200,000 or less, from the viewpoint of dyeability and melt processability.

[0022] Examples of polymers having a vinyl acetate monomer unit include a homopolymer of vinyl acetate and a copolymer of vinyl acetate with one or more other monomer units selected from the group consisting of acrylonitrile, vinylpyrrolidone, acrylic acid esters, and methacrylic acid esters. Among these, from the viewpoint of dyeability, a homopolymer of vinyl acetate or a copolymer of vinyl acetate with other monomer units is preferred, a homopolymer of vinyl acetate (poly(vinyl acetate)) and / or a copolymer of vinylpyrrolidone and vinyl acetate is more preferred, and a copolymer of vinylpyrrolidone and vinyl acetate is particularly preferred. The poly(vinyl acetate) is not particularly limited, but from the viewpoint of dyeability and melt processability, the number average degree of polymerization is preferably 100 to 3000, more preferably 500 to 2000.

[0023] In the copolymer of vinyl acetate and other monomer units, the content of vinyl acetate is preferably 30 parts by mass or more, assuming that the total mass of vinyl acetate and other monomer units is 100 parts by mass.

[0024] Examples of polymers having a methacrylic acid ester monomer unit include homopolymers of monomer units such as methyl methacrylate, ethyl methacrylate, n-butyl methacrylate, 2-hydroxyethyl methacrylate, and glycidyl methacrylate, and copolymers containing one or more of these monomer units as the main component. Among these, a homopolymer of glycidyl methacrylate (poly(glycidyl methacrylate)) is preferred from the viewpoint of dyeability.

[0025] <Polymer (A)> The polymer (A) is a homopolymer or copolymer containing one or more monomers selected from the group consisting of acrylonitrile, vinyl halide, and vinylidene halide.

[0026] Examples of the vinyl halides include vinyl chloride, vinyl bromide, and vinyl iodide. Examples of the vinylidene halides include vinylidene chloride, vinylidene bromide, and vinylidene iodide. These may be used alone or in combination of two or more. From the viewpoint of heat resistance, it is preferable to use vinyl chloride and / or vinylidene chloride, and it is more preferable to use vinyl chloride.

[0027] The mass average molecular weight (Mw) of the polymer (A) is preferably 10,000 or more and 300,000 or less, and more preferably 30,000 or more and 150,000 or less, from the viewpoints of melt processability and fiber properties.

[0028] From the viewpoint of the feel of the fiber for artificial hair, the polymer (A) is preferably an acrylic resin and / or a vinyl chloride resin.

[0029] (acrylic resin) The acrylic resin is a copolymer containing acrylonitrile and one or more halogenated monomers selected from the group consisting of vinyl halides and vinylidene halides.

[0030] As the vinyl halide and vinylidene halide, the above-mentioned ones may be used appropriately. From the viewpoint of heat resistance, it is preferable to use vinyl chloride and / or vinylidene chloride as the halogenated monomer, and it is more preferable to use vinyl chloride.

[0031] The acrylic resin preferably contains 35 to 85 parts by mass of acrylonitrile and 15 to 65 parts by mass of halogenated monomer, where the total mass of acrylonitrile and halogenated monomer is 100 parts by mass.

[0032] From the viewpoint of melt processability, the acrylic resin is a copolymer of a macromonomer having a polymer composed of acrylonitrile, a halogenated monomer, and an ethylenically unsaturated monomer containing a double bond in its main chain, and when the total mass of the macromonomer having a polymer composed of acrylonitrile, a halogenated monomer, and an ethylenically unsaturated monomer containing a double bond in its main chain (hereinafter also simply referred to as "macromonomer") is taken as 100 parts by mass, the content of the macromonomer is preferably 1 part by mass or more and 30 parts by mass or less, and the content of acrylonitrile is preferably 35 parts by mass or more and 64 parts by mass or less. It is more preferable that the content of the halogenated monomer is 35 parts by mass or more and 64 parts by mass or less, and the content of the macromonomer is 1 part by mass or more and 30 parts by mass or less; it is even more preferable that the content of the acrylonitrile is 35 parts by mass or more and 59 parts by mass or less, the content of the halogenated monomer is 40 parts by mass or more and 64 parts by mass or less, and the content of the macromonomer is 1 part by mass or more and 20 parts by mass or less; it is particularly preferable that the content of the acrylonitrile is 35 parts by mass or more and 54 parts by mass or less, the content of the halogenated monomer is 45 parts by mass or more and 64 parts by mass or less, and the content of the macromonomer is 1 part by mass or more and 15 parts by mass or less.

[0033] Generally, a macromonomer refers to an oligomer molecule having a reactive functional group at the polymer end, and the reactive functional group (also referred to as a polymerizable functional group) is, for example, an allyl group, a vinylsilyl group, a vinyl ether group, a dicyclopentadienyl group, or a group having a polymerizable carbon-carbon double bond represented by the following general formula (1), at least one per molecule at the molecular end. Such macromonomers can usually be produced by radical polymerization. In particular, due to good reactivity with acrylonitrile and halogenated monomers such as vinyl chloride, it is preferable that the reactive functional group in the macromonomer has a polymerizable carbon-carbon double bond represented by the following general formula (1).

[0034] CH2=C(R)―C(O)O― (1) In the general formula (1), R represents hydrogen or a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms. Specific examples of R are not particularly limited, and include, for example, -H, -CH3, -CH2CH3, -(CH2) n A group selected from the group consisting of CH3 (n is an integer of 2 to 19), -C6H5, -CH2OH, and -CN is preferred, and a group selected from the group consisting of -H and -CH3 is more preferred. Specifically, a poly(2-methoxyethyl acrylate) macromonomer having an acryloyl group at one end may be used.

[0035] In this specification, a range indicated by "... to..." is the same as a range indicated by "... or more... or less."

[0036] The method for producing the polymer of the main chain of the macromonomer, which is made of an ethylenically unsaturated monomer containing a double bond, is not particularly limited, and any conventionally known production method can be used. For example, Japanese Patent Application Laid-Open No. 2006-299240 describes in detail a production method for the macromonomer used in one or more embodiments of the present invention, and any of these production methods can be used. However, a controlled radical polymerization method is usually used, and a living radical polymerization method is more preferably used from the viewpoint of ease of control, and an atom transfer radical polymerization method is particularly preferred.

[0037] In the macromonomer, the polymer of the ethylenically unsaturated monomer containing a double bond in its main chain is not particularly limited, and various ethylenically unsaturated monomers containing a double bond can be used to form the polymer. Examples include (meth)acrylic acid ester monomers, styrene monomers, nitrile group-containing vinyl monomers, amide group-containing vinyl monomers, fluorine-containing vinyl monomers, silicon-containing vinyl monomers, maleimide monomers, vinyl esters, alkenes, and conjugated dienes. Other examples that can be used include maleic anhydride, maleic acid, monoalkyl and dialkyl esters of maleic acid; fumaric acid, monoalkyl and dialkyl esters of fumaric acid; allyl chloride; and allyl alcohol.

[0038] (Method of manufacturing acrylic resin) As a method for producing an acrylic resin, copolymerization in an aqueous medium is preferred from the viewpoints of ease of polymerization control and ease of separation and washing of polymer particles after polymerization. Examples of polymerization methods in an aqueous medium include suspension polymerization, microsuspension polymerization, and emulsion polymerization. Among these, suspension polymerization and microsuspension polymerization are preferred from the viewpoint of polymerization stability, and suspension polymerization is more preferred for obtaining an acrylic resin having an average particle size of 1 μm or more and 1000 μm or less.

[0039] In the suspension polymerization method or the microsuspension polymerization method, the thermoplastic acrylic resin is obtained in the form of a latex or a slurry, and there are no particular limitations on the method for drying this to obtain a powdery or granular copolymer resin. Examples include a method in which the latex or slurry is dehydrated and then dried by a static drying method using a hot air dryer or the like.

[0040] In the suspension polymerization method or the microsuspension polymerization method, the above-mentioned monomers, suspension dispersant, polymerization initiator, chain transfer agent, etc. are charged all at once, in portions, or continuously as needed, and the copolymerization reaction can be carried out at a predetermined polymerization temperature, for example, from 25°C to 100°C.

[0041] Examples of the suspension dispersant that can be used include organic polymer dispersants such as partially saponified polyvinyl acetate, water-soluble cellulose ethers such as methyl cellulose, hydroxyethyl cellulose, hydroxypropyl cellulose, hydroxypropylmethyl cellulose, and carboxymethyl cellulose, polyethylene oxide, polyvinylpyrrolidone, polyacrylic acid, vinyl acetate-maleic acid copolymer, styrene-maleic acid copolymer, gelatin, and starch. These may be used alone or in combination of two or more.

[0042] The polymerization initiator is not particularly limited, but it is preferable to use an oil-soluble polymerization initiator having a 10-hour half-life temperature of 30 to 65°C. Examples of such oil-soluble polymerization initiators include organic peroxide polymerization initiators such as diisobutyl peroxide, cumyl peroxyneodecanoate, diisopropyl peroxydicarbonate, di(2-ethylhexyl)peroxydicarbonate, t-butyl peroxypivalate, t-butyl peroxyneodecanoate, 1,1,3,3-tetramethylbutyl peroxyneodecanoate, dilauroyl peroxide, and di(3,5,5-trimethylhexanoyl)peroxide. These oil-soluble polymerization initiators may be used alone or in combination of two or more. These oil-soluble polymerization initiators can be added without any particular restrictions, but when used by dissolving them in an organic solvent, examples of the organic solvent include aromatic hydrocarbons such as toluene, xylene, and benzene; aliphatic hydrocarbons such as hexane and isoparaffin; ketones such as acetone and methyl ethyl ketone; and esters such as ethyl acetate, butyl acetate, and dioctyl phthalate. These organic solvents may be used alone or in combination of two or more.

[0043] The chain transfer agent is not particularly limited, but it is preferable to use a thiol-based chain transfer agent.As such a thiol-based chain transfer agent, for example, ethanethiol, 1-propanethiol, 1-butanethiol, 1-octanethiol, 1-decanethiol, 1-dodecanethiol, 1-hexadecanethiol, 1-octadecanethiol, cyclohexanethiol, benzenethiol, allyl mercaptan, 2-mercaptoethanol, α-thioglycerol, thioglycolic acid, methyl thioglycolate, ethyl thioglycolate, 2-aminoethanethiol, 2-mercaptoethanesulfonic acid sodium, 4-nitrobenzenethiol, cysteine, etc. can be mentioned.

[0044] During the polymerization, surfactants, dispersing aids, antioxidants, polymerization degree regulators, particle size regulators, pH regulators, gelling property improvers, antistatic agents, stabilizers, scale inhibitors, and the like may be used appropriately as needed.

[0045] (Vinyl chloride resin) Vinyl chloride resins are homopolymers made of vinyl chloride or vinyl chloride copolymers containing vinyl chloride as a main component. In vinyl chloride copolymers, monomers copolymerizable with vinyl chloride (hereinafter also referred to as "other monomers") are not particularly limited, but examples thereof include vinyl esters such as vinyl acetate and vinyl propionate, acrylic esters such as butyl acrylate and 2-ethylhexyl acrylate, and olefins such as ethylene and propylene.

[0046] In the vinyl chloride copolymer, the content of vinyl chloride is preferably 70 parts by mass or more, assuming that the total mass of vinyl chloride and other monomers is 100 parts by mass.

[0047] The vinyl chloride resin can be produced, for example, by the method described in Japanese Patent Application Laid-Open No. 5-140205.

[0048] <Resin composition> In one or more embodiments of the present invention, the resin composition includes a polymer (A) and a polymer (B). In addition to the polymer (A) and the polymer (B), the resin composition may include other polymers within the scope of the present invention. Examples of the other polymers include polymers containing acrylic acid esters or methacrylic acid esters. The amount of the other polymer may be 20 parts by mass or less, where the total amount of the polymer (A) and the polymer (B) is 100 parts by mass.

[0049] From the viewpoint of melt processability and dyeability (particularly dyeability with a dye containing an acid dye), the resin composition preferably contains 70 to 92.5 parts by mass of polymer (A) and 7.5 to 30 parts by mass of polymer (B), 80 to 90 parts by mass of polymer (A), and 10 to 20 parts by mass of polymer (B), where the total amount of polymer (A) and polymer (B) is taken as 100 parts by mass.

[0050] The resin composition may be prepared by blending polymer (A) and polymer (B) with a plasticizer (also referred to simply as "plasticizer"), which is an organic compound compatible with polymer (A) and has a boiling point of 200°C or higher. As used herein, "compatible" means that the polymer dissolves when 10 mg of the polymer and 2 g of the organic compound having a boiling point of 200°C or higher are placed in a 19 mL borosilicate glass tube, the tube is sealed with a silicone stopper, and the tube is heated at 160°C for 30 minutes with occasional stirring. Furthermore, as used herein, "boiling point" refers to the standard boiling point at 1 atmospheric pressure (760 mmHg).

[0051] The plasticizer is not particularly limited as long as it is an organic compound that is compatible with the polymer (A) and has a boiling point of 200° C. or higher. Examples of suitable plasticizers include sulfone compounds such as dimethyl sulfone, diethyl sulfone, dipropyl sulfone, dibutyl sulfone, diphenyl sulfone, vinyl sulfone, ethyl methyl sulfone, methyl phenyl sulfone, methyl vinyl sulfone, and 3-methyl sulfolane; sulfoxide compounds such as dipropyl sulfoxide, tetramethylene sulfoxide, diisopropyl sulfoxide, methyl phenyl sulfoxide, dibutyl sulfoxide, diisobutyl sulfoxide, di-p-tolyl sulfoxide, diphenyl sulfoxide, and benzyl sulfoxide; lactides such as lactide lactic acid; lactams such as pyrrolidone, N-vinyl pyrrolidone, ε-caprolactam, and N-methyl caprolactam; and lactones such as γ-butyrolactone, γ-hexalactone, γ-heptalactone, γ-octalactone, ε-caprolactone, and ε-octalactone. These plasticizers may be used singly or in combination of two or more.

[0052] When fibers are maintained at a temperature higher than the melting point of the plasticizer, the plasticizer may liquefy and ooze out onto the fiber surface, degrading the appearance and feel of the fiber. It then solidifies upon returning to room temperature (25±5°C), potentially causing problems such as inter-fiber adhesion. In particular, during overseas transport, the room temperature may rise to 60°C in a container on board, and during fiber processing, the temperature may reach 90°C for a short period. Therefore, the melting point of the plasticizer is preferably 60°C or higher, more preferably 90°C or higher. For example, it is preferable to use one or more plasticizers selected from the group consisting of dimethyl sulfone, lactide lactic acid, and ε-caprolactam, and it is more preferable to use one or more plasticizers selected from the group consisting of dimethyl sulfone and lactide lactic acid.

[0053] From the viewpoint of melt processability, the resin composition preferably contains 0.1 to 50 parts by mass of the plasticizer per 100 parts by mass of the total amount of polymer (A) and polymer (B). When the blending amount of the plasticizer is 50 parts by mass or less, the melt processability is good and the resin viscosity during melt kneading is improved, which tends to improve kneading efficiency. From the viewpoint of heat resistance, the resin composition preferably contains 30 parts by mass or less of the plasticizer per 100 parts by mass of the total amount of polymer (A) and polymer (B), more preferably 25 parts by mass or less, even more preferably 20 parts by mass or less, and particularly preferably 15 parts by mass or less. From the viewpoint of melt processability, the resin composition preferably contains 0.5 parts by mass or more of the plasticizer per 100 parts by mass of the total amount of polymer (A) and polymer (B), more preferably 1 part by mass or more, and even more preferably 2.5 parts by mass or more. For example, when dimethyl sulfone is used, if the amount is 2.5 parts by mass or more, the melt processability is good, and when 20 parts by mass of dimethyl sulfone is mixed, the melt processability can be achieved even at a low temperature, for example, 115°C, which is 5°C higher than the melting point of dimethyl sulfone.

[0054] The resin composition may further contain a stabilizer for thermal stability. The stabilizer is not particularly limited as long as it imparts thermal stability. From the viewpoints of improving melt processability, suppressing coloration, and ensuring transparency, the stabilizer is preferably one or more selected from the group consisting of epoxy-based heat stabilizers, hydrotalcite-based heat stabilizers, tin-based heat stabilizers, Ca-Zn-based heat stabilizers, and β-diketone-based heat stabilizers.

[0055] Epoxy heat stabilizers include butyl glycidyl ether, neopentyl glycol diglycidyl ether, phenyl glycidyl ether, orthocresyl glycidyl ether, meta-para-cresyl glycidyl ether, glycidyl methacrylate, 1,6-hexanediol diglycidyl ether, trimethylolpropane polyglycidyl ether, hexahydrophthalic acid diglycidyl ester, hydrogenated bisphenol A diglycidyl ether, propylene glycol diglycidyl ether, tripropylene glycol diglycidyl ether, and polypropylene glycol diglycidyl ether. Examples of the vinyl monomers that can be used include homopolymers or copolymers of one or more vinyl monomers selected from the group consisting of diglycidyl ether, fatty acid-modified epoxy, diethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, glycerin polyglycidyl ether, diglycerin polyglycidyl ether, polyglycerin polyglycidyl ether, sorbitol-based polyglycidyl ether, 1,3,5-tris(2,3-epoxypropyl)-1,3,5-triazine, tetrahydrophthalic acid diglycidyl ester, and glycidyl acrylate. Among these, from the viewpoints of coloration inhibition and transparency, it is preferable to use polyglycidyl methacrylate, a glycidyl methacrylate copolymer, tetrabromobisphenol A diglycidyl ether, hexahydrophthalic acid diglycidyl ester, hydrogenated bisphenol A diglycidyl ether, etc., and it is more preferable to use polyglycidyl methacrylate, a glycidyl methacrylate copolymer, tetrabromobisphenol A diglycidyl ether, etc., which have a boiling point of 200°C or higher and are solid at 50°C.

[0056] The hydrotalcite-based heat stabilizer is not particularly limited as long as it is a hydrotalcite compound. It may be a natural product or a synthetic product. For example, Alcamizer (registered trademark) manufactured by Kyowa Chemical Industry Co., Ltd. can be used.

[0057] The tin-based stabilizer is not particularly limited as long as it has a heat stabilizing effect. For example, mercaptotin-based heat stabilizers such as dimethyltin mercapto, dimethyltin mercaptide, dibutyltin mercapto, dioctyltin mercapto, dioctyltin mercapto polymer, and dioctyltin mercaptoacetate, maleatetin-based heat stabilizers such as dimethyltin maleate, dibutyltin maleate, dioctyltin maleate, and dioctyltin maleate polymer, and lauratetin-based heat stabilizers such as dimethyltin laurate, dibutyltin laurate, and dioctyltin laurate can be used.

[0058] The Ca-Zn stabilizer is not particularly limited as long as it has a heat stabilizing effect, and examples that can be used include zinc stearate, calcium stearate, zinc 12-hydroxystearate, and calcium 12-hydroxystearate.

[0059] The β-diketone stabilizer is not particularly limited as long as it has a heat stabilizing effect, and examples thereof include stearoylbenzoylmethane (SBM) and dibenzoylmethane (DBM).

[0060] The stabilizers may be used alone or in combination of two or more.

[0061] From the viewpoints of improving melt processability, suppressing coloration, and ensuring transparency, the stabilizer is preferably at least one selected from the group consisting of polyglycidyl methacrylate, tetrabromobisphenol A diglycidyl ether, hydrotalcite, zinc 12-hydroxystearate, calcium 12-hydroxystearate, stearoylbenzoylmethane (SBM), and dibenzoylmethane (DBM).

[0062] The resin composition preferably contains 0.1 to 30 parts by mass of the stabilizer relative to 100 parts by mass of the total of polymer (A) and polymer (B), more preferably 0.2 to 20 parts by mass, and even more preferably 0.5 to 10 parts by mass. When the amount is 0.1 part by mass or more, the coloration suppression effect is good. When the amount is 30 parts by mass or less, the coloration suppression effect is good, transparency can be ensured, and the deterioration of the mechanical properties of the resin composition molded article is minimal.

[0063] The resin composition may contain a lubricant to reduce friction and heat generation due to shear between the polymer (A) and polymer (B) and the processing machine, and to improve fluidity and mold releasability, as long as the object of the present invention is not impaired. Examples of lubricants that can be used include hydrocarbon-based lubricants such as stearic acid monoglyceride, stearyl stearate, fatty acid ester-based lubricants, liquid paraffin, paraffin wax, and synthetic polyethylene wax, fatty acid-based lubricants such as stearic acid, higher alcohol-based lubricants such as stearyl alcohol, aliphatic amide-based lubricants such as stearic acid amide, oleic acid amide, and erucic acid amide, alkylene fatty acid amide-based lubricants such as methylene bisstearic acid amide and ethylene bisstearic acid amide, and metal soap-based lubricants such as lead stearate, zinc stearate, calcium stearate, and magnesium stearate. These may be used alone or in combination. The amount of lubricant added may be 10 parts by mass or less per 100 parts by mass of the combined amount of polymer (A) and polymer (B).

[0064] The resin composition may contain a processing aid to improve spinnability. When fibers are made from the resin composition, it is preferable to contain a (meth)acrylate polymer and / or a styrene-acrylonitrile copolymer as the processing aid. Examples of the (meth)acrylate polymer include copolymers of (meth)acrylate with copolymerization components such as butyl (meth)acrylate, isobutyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, styrene, vinyl acetate, and acrylonitrile. Commercially available (meth)acrylate polymers, such as Kaneka's "Kane Ace PA20" and "Kane Ace PA101," can also be used. The amount of processing aid added may be 10 parts by mass or less per 100 parts by mass of the vinyl polymer. "(Meth)acrylate" refers to methacrylate or acrylate.

[0065] (Method of producing resin composition) The resin composition can be obtained, for example, by melt-kneading a powder mixture containing the polymer (A) and the polymer (B). The method of melt-kneading is not particularly limited, and a general method for melt-kneading a thermoplastic resin can be used.

[0066] For ease of operation, the plasticizer is first mixed with a mixed powder of polymer (A) and polymer (B) to form a powder mixture. From the viewpoint of ease of mixing, the moisture content of both polymer (A) and polymer (B) is preferably 2% by mass or less, more preferably 0.5% by mass or less. The moisture content of polymer (A) and polymer (B) can be measured using an MX heat-drying moisture meter manufactured by A&D Co., Ltd. at 160°C for 10 minutes. Preferably, the stabilizer is mixed in. Furthermore, lubricants, processing aids, etc. are mixed in as needed. The mixing method is not particularly limited, and a mixer such as a Henschel mixer, super mixer, or ribbon blender can be used. The temperature, time, and other conditions during the mixing operation are not particularly limited as long as a powder mixture can be obtained. From the viewpoint of easily obtaining a powder mixture and, if necessary, melting and adsorbing various additives onto the surface of the mixed powder of polymer (A) and polymer (B), it is preferable to set the temperature in the range of 0°C or higher and 120°C or lower during the mixing operation, and to cool the mixture at the end of the mixing operation to a temperature 10°C or higher lower than the glass transition temperature of the powder mixture so as to prevent the powders from fusing together or to equipment such as piping during transfer.

[0067] Next, the powder mixture is melt-kneaded. The temperature during kneading is equal to or higher than the glass transition temperature of the kneaded mixture of polymer (A), polymer (B), and plasticizer, and from the viewpoint of suppressing coloration due to thermal decomposition of polymer (A) and polymer (B), it is preferably 40°C to 200°C, more preferably 80°C to 185°C, and even more preferably 100°C to 165°C. For kneading, there are no particular limitations, but kneading devices such as a single-screw extruder, a twin-screw extruder, a plastomill, and a pressure kneader can be used. By melt-kneading the powder mixture, a resin composition in the form of blocks, strands, or pellets can be obtained.

[0068] <Synthetic fiber> Acrylic fibers can be produced from a resin composition using an acrylic resin as the polymer (A), and vinyl chloride fibers can be produced from a resin composition using a vinyl chloride resin as the polymer (A). Specifically, in the case of acrylic fibers, acrylic fibers can be obtained by melt-spinning a resin composition containing the acrylic resin (e.g., a resin composition in pellet form after melt-kneading). Similarly, vinyl chloride fibers can be obtained by melt-spinning a resin composition containing a vinyl chloride resin. To explain acrylic fibers, first, the resin composition is melt-spun into a fibrous undrawn yarn. Specifically, a molten mixture (pellet-shaped resin composition) of the resin composition melt-kneaded in an extruder, such as a single-screw extruder, counter-rotating twin-screw extruder, or conical twin-screw extruder, is discharged from the spinning nozzle of the extruder, passed through a heating tube, and heated to a temperature above which the fibrous resin composition can be taken up by a take-up machine. The undrawn yarn is then formed by taking up the resin composition while cooling it to a temperature below the glass transition point by air-cooling, wind-cooling, or other means. The extruder is preferably operated in a temperature range of, for example, 120°C to 200°C. The ratio of the take-up speed to the discharge speed is not particularly limited, but is preferably taken up at a speed ratio of, for example, 1 to 100 times, and more preferably 5 to 50 times from the viewpoint of spinning stability. The diameter of the spinning nozzle is not particularly limited, but is, for example, preferably 0.05 mm to 2 mm, more preferably 0.1 mm to 1 mm. The material discharged from the spinning nozzle is preferably extruded at a nozzle temperature at which melt fracture does not occur or higher. The temperature of the spinning nozzle is preferably 160°C or higher, more preferably 170°C or higher. The temperature of the heating barrel is preferably 200°C or higher, more preferably 230°C or higher. The cooling temperature is preferably -196°C to 40°C in air-cooling, more preferably 0°C to 30°C, and preferably 5°C to 60°C in water-cooling, more preferably 10°C to 40°C.

[0069] The undrawn yarn obtained above can be drawn by a known method and, if necessary, heat-relaxed. For example, when used as artificial hair, it is preferable to produce fibers (filaments) with a single fiber fineness of 2 dtex to 100 dtex. The drawing conditions are a temperature of 70°C to 150°C in a dry heat atmosphere, with a draw ratio of preferably 1.1 to 6 times, and more preferably 1.5 to 4.5 times. The drawn fiber can be heat-relaxed at a relaxation rate of preferably 1% to 50%, more preferably 5% to 40%, to reduce the thermal shrinkage. Heat-relaxing is preferable to smooth out the irregularities on the fiber surface and achieve a smooth texture similar to that of human hair. The undrawn or drawn yarn can also be washed with water to control the fineness. In the present invention, the single fiber fineness is measured in accordance with JIS L 1013.

[0070] The apparent glass transition temperature of the acrylic fiber (heat-treated yarn) obtained above is preferably 60°C or higher, since the room temperature inside a container on board may rise to 60°C during overseas transportation and from the viewpoint of preventing fusion of fibers together during heat processing.

[0071] Synthetic fibers such as acrylic fibers can be dyed with a dye (C), particularly with a dye containing an acid dye, and are easily dyeable with acid dyes.

[0072] <Headdress products> The synthetic fibers have a good feel and excellent dyeability, particularly with dyes containing acid dyes such as acid dyes for human hair, and therefore can be suitably used as artificial hair in head accessories. The synthetic fibers may be used alone as artificial hair or in combination with other fibers for artificial hair.

[0073] The head accessories are not particularly limited, but preferably include one selected from the group consisting of hair wigs, hairpieces, weaving, hair extensions, braided hair, hair accessories, and doll hair.

[0074] The head accessory product contains synthetic fibers that are easily dyeable with acid dyes, and therefore can be dyed to a desired color with a human hair dye containing an acid dye. [Example]

[0075] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to the following examples.

[0076] (Stainability) The dyeability of the fibers and / or resin compositions was evaluated by the following method: An acidic dye for human hair (manufactured by Kiss Products Inc., product name "Express Color Semi-Permanent #K98 Black") was applied to the fibers and / or resin compositions, and after 25 minutes at room temperature (25±5°C), the fibers and / or resin compositions were washed with an aqueous emulsion (Scorerol 700:5 g / L) of ion-exchanged water and a nonionic surfactant (manufactured by Kitahiro Chemical, product name "Scorerol 700"), dried, and the color change was visually evaluated according to the following criteria.

[0077] 1: No dyeing at all 2: Slightly stained 3: Dyeing 4: Dyes well (compatibility) 10 mg of polymer (A) and 2 g of plasticizer were placed in a 19 mL borosilicate glass tube, and the glass tube was sealed with a silicone stopper. The tube was then heated at 160°C for 30 minutes with occasional stirring, and it was observed whether polymer (A) was dissolved.

[0078] (Solubility) 0.1 g of polymer (B) was added to 5 mL of benzyl alcohol, and the mixture was stirred at room temperature (25±5° C.) for 1 hour, and it was observed whether polymer (B) was dissolved.

[0079] (Production Example 1) An acrylic resin was produced as polymer (A). A polymerization reactor was charged with 54 parts by weight of vinyl chloride, 7.5 parts by weight of acrylonitrile, 3 parts by weight of poly(2-methoxyethyl acrylate) macromonomer with one acryloyl group at one end, 210 parts by weight of ion-exchanged water, 0.4 parts by weight of partially saponified polyvinyl acetate (saponification degree approximately 70 mol%, number-average polymerization degree 1700), and 0.75 parts by weight of 1,1,3,3-tetramethylbutyl peroxyneodecanoate. The temperature inside the polymerization reactor was then cooled to 15°C or below, and the mixture was stirred and dispersed for 15 minutes. The temperature inside the polymerization reactor was then raised to 50°C to initiate polymerization. The polymerization temperature was then maintained at 50°C for 4 hours, then raised to 52.5°C for another 2 hours, and then raised to 55°C for another 2 hours. During the polymerization, 35.5 parts by weight of acrylonitrile and 0.7 parts by weight of 2-mercaptoethanol were continuously added at a constant rate from immediately after the start of polymerization until the 7th hour. After recovering the unreacted vinyl chloride monomer from the polymerization reactor, the slurry was discharged. The resulting slurry was dehydrated and dried in a hot air dryer at 60°C for 24 hours to obtain an acrylic resin. The resulting acrylic resin consisted of 40.7% by mass of acrylonitrile, 56.3% by mass of vinyl chloride, and 3.0% by mass of poly(2-methoxyethyl acrylate), and had a mass average molecular weight of approximately 39,000.

[0080] Furthermore, when the compatibility was evaluated as described above, it was confirmed that the acrylic resin obtained in Production Example 1 was compatible with dimethyl sulfone.

[0081] Example 1 To a total of 100 parts by mass of 90 parts by mass of the acrylic resin obtained in Production Example 1 and 10 parts by mass of poly(vinyl acetate) (number average polymerization degree 500, manufactured by Kishida Chemical) as polymer (B), 2.5 parts by mass of dimethyl sulfone as a plasticizer, 6.98 parts by mass of a stabilizer, 0.384 parts by mass of a lubricant, and 3 parts by mass of a processing aid were added and mixed using a mixer to obtain a powder mixture. Next, 62 g of the powder mixture was kneaded in a Labo Plastomill (manufactured by Toyo Seiki, model "4C150") under conditions of 115 °C, 50 rpm, and 10.5 minutes to obtain a resin composition.

[0082] Example 2 A resin composition was obtained in the same manner as in Example 1, except that poly(vinyl acetate) (number average polymerization degree 2000, manufactured by Fujifilm Wako Pure Chemical Industries, Ltd.) was used instead of poly(vinyl acetate) (number average polymerization degree 500).

[0083] Example 3 To a total of 100 parts by mass of 80 parts by mass of the acrylic resin obtained in Production Example 1 and 20 parts by mass of a vinylpyrrolidone-vinyl acetate copolymer (40% by mass of vinyl acetate, 60% by mass of vinylpyrrolidone, mass-average molecular weight 65,000) as polymer (B), 2.5 parts by mass of dimethyl sulfone as a plasticizer, 6.98 parts by mass of a stabilizer, 0.384 parts by mass of a lubricant, and 3 parts by mass of a processing aid were added and mixed using a Henschel mixer to obtain a powder mixture. The powder mixture was then extruded using a laboratory extruder (Toyo Seiki Co., Ltd., model number "4C150", combined with a 20 mm extrusion unit and a 2 mm strand nozzle) to obtain strands. The extruder was operated at a temperature range of 120 to 150 °C. The obtained strands were air-cooled and then pelletized to obtain resin composition pellets.

[0084] The resin composition pellets obtained above were extruded into a laboratory extruder (Toyo Seiki Co., Ltd., model number "4C150", 20 mm extrusion unit, downward die for measuring melt viscosity) with a hole cross-sectional area of ​​0.0793 mm 2 Using a 12-hole cocoon-shaped spinning nozzle (combination of a 12-hole cocoon-shaped spinning nozzle), extrusion melt spinning was performed at a cylinder temperature of 140 to 160°C and a nozzle temperature of 230°C. The yarn was taken up at a nozzle draft of approximately 5 times, yielding an undrawn yarn with a fineness of 200 dtex. The undrawn yarn was then dry-heat drawn at a draw ratio of 3 times in a dry heat atmosphere at 105°C, yielding a fiber with a single fiber fineness of approximately 70 dtex.

[0085] Example 4 Resin composition pellets were obtained in the same manner as in Example 3, except that poly(glycidyl methacrylate) (mass average molecular weight 10,000, manufactured by NOF Corp., product name "Marproof G-01100") was used as polymer (B) instead of vinylpyrrolidone-vinyl acetate copolymer.

[0086] Melt spinning was performed in the same manner as in Example 3, except that the resin composition pellets obtained above were used. The undrawn yarn was taken up at a nozzle draft of approximately 5 times to obtain an undrawn yarn having a fineness of 200 dtex. The undrawn yarn was then hot-drawn at a draw ratio of 3 times in a hot atmosphere at 105°C to obtain a fiber having a single fiber fineness of approximately 70 dtex.

[0087] Example 5 Resin composition pellets were obtained in the same manner as in Example 3, except that an acrylonitrile-styrene copolymer (30% by mass of acrylonitrile, 70% by mass of styrene, mass average molecular weight 86,000, manufactured by Galata Chemicals, product name "BLENDEX 5433") was used as polymer (B) instead of the vinylpyrrolidone-vinyl acetate copolymer.

[0088] Melt spinning was performed in the same manner as in Example 3, except that the resin composition pellets obtained above were used. The undrawn yarn was taken up at a nozzle draft of approximately 5 times to obtain an undrawn yarn having a fineness of 200 dtex. The undrawn yarn was then hot-drawn at a draw ratio of 3 times in a hot atmosphere at 105°C to obtain a fiber having a single fiber fineness of approximately 70 dtex.

[0089] Example 6 Resin composition pellets were obtained in the same manner as in Example 3, except that poly(vinyl acetate) (number average polymerization degree 500, manufactured by Kishida Chemical Co., Ltd.) was used as polymer (B) instead of vinylpyrrolidone-vinyl acetate copolymer, and the total amount was 100 parts by mass of 90 parts by mass of the acrylic resin obtained in Production Example 1 and 10 parts by mass of poly(vinyl acetate).

[0090] Melt spinning was performed in the same manner as in Example 3, except that the resin composition pellets obtained above were used. The undrawn yarn was taken up at a nozzle draft of approximately 5 times to obtain an undrawn yarn having a fineness of 200 dtex. The undrawn yarn was then hot-drawn at a draw ratio of 3 times in a hot atmosphere at 105°C to obtain a fiber having a single fiber fineness of approximately 70 dtex.

[0091] (Comparative Example 1) A resin composition was obtained in the same manner as in Example 1, except that no poly(vinyl acetate) was used and the acrylic resin obtained in Production Example 1 was used in an amount of 100 parts by mass.

[0092] (Comparative Example 2) A resin composition was obtained in the same manner as in Example 1, except that the acrylic resin obtained in Production Example 1 was changed to 95 parts by mass and poly(vinyl acetate) (number average degree of polymerization 500) was changed to 5 parts by mass.

[0093] (Comparative Example 3) A resin composition was obtained in the same manner as in Example 2, except that the acrylic resin obtained in Production Example 1 was changed to 95 parts by mass and poly(vinyl acetate) (number average degree of polymerization 2000) was changed to 5 parts by mass.

[0094] Comparative Example 4 Resin composition pellets were obtained in the same manner as in Example 3, except that the vinylpyrrolidone-vinyl acetate copolymer was not used and the amount of the acrylic resin obtained in Production Example 1 was changed to 100 parts by mass.

[0095] Melt spinning was performed in the same manner as in Example 3, except that the resin composition pellets obtained above were used. The undrawn yarn was taken up at a nozzle draft of approximately 6.8 times to obtain an undrawn yarn having a fineness of 150 dtex. The undrawn yarn was then hot-drawn at a draw ratio of 3 times in a hot atmosphere at 105°C to obtain a fiber having a single fiber fineness of approximately 48 dtex.

[0096] The solubility of the polymers (B) used in the examples and comparative examples, specifically poly(vinyl acetate) having a number-average degree of polymerization of 500, poly(vinyl acetate) having a number-average degree of polymerization of 2000, vinylpyrrolidone-vinyl acetate copolymer, poly(glycidyl methacrylate), and acrylonitrile-styrene copolymer in benzyl alcohol was evaluated as described above, and the results are shown in Table 1 below.

[0097] The dyeability of the resin compositions or fibers obtained in Examples 1 to 6 and Comparative Examples 1 to 4 was evaluated as described above, and the results are shown in Table 2 below.

[0098] [Table 1]

[0099] [Table 2]

[0100] The results in Tables 1 and 2 show that the resin compositions or synthetic fibers of Examples 1 to 6 containing a predetermined amount of polymer (A) and polymer (B) soluble in benzyl alcohol can be dyed with a human hair dye containing an acid dye.

[0101] On the other hand, the resin compositions or fibers of Comparative Examples 1 to 4, which did not contain polymer (B) soluble in benzyl alcohol or contained a small amount of polymer (B) soluble in benzyl alcohol, were not dyed at all with the human hair dye containing an acid dye.

[0102] The present invention is not particularly limited, and may include, for example, one or more of the following embodiments.

[0103] [1] A resin composition comprising a polymer (A) and a polymer (B), Polymer (A) is a polymer containing one or more monomer units selected from the group consisting of acrylonitrile, vinyl halide, and vinylidene halide; Polymer (B) is a polymer that is soluble in benzyl alcohol, A resin composition comprising 70 parts by mass or more and 92.5 parts by mass or less of the polymer (A) and 7.5 parts by mass or more and 30 parts by mass or less of the polymer (B), where the total amount of the polymer (A) and the polymer (B) is 100 parts by mass.

[0104] [2] The resin composition according to [1], wherein the polymer (B) is a polymer containing one or more monomer units selected from the group consisting of vinyl acetate, vinylpyrrolidone, acrylic acid esters, methacrylic acid esters, and styrene.

[0105] [3] The resin composition according to [1] or [2], wherein the polymer (B) comprises at least one selected from the group consisting of a vinyl acetate homopolymer, a vinylpyrrolidone-vinyl acetate copolymer, an acrylonitrile-styrene copolymer, and poly(glycidyl methacrylate).

[0106] [4] The resin composition according to any one of [1] to [3], wherein the polymer (A) is an acrylic resin.

[0107] [5] The resin composition according to [4], wherein the acrylic resin is a copolymer of one or more halogenated monomers selected from the group consisting of acrylonitrile, vinyl halide, and vinylidene halide, and a macromonomer having an ethylenically unsaturated monomer containing a double bond in the main chain.

[0108] [6] The resin composition according to any one of [1] to [3], wherein the polymer (A) is a vinyl chloride resin.

[0109] [7] A method for dyeing a resin composition, comprising: permeating the resin composition according to any one of [1] to [6] with a dyeing agent containing a dye (C) and an alcohol to color the resin composition.

[0110] [8] The method for dyeing a resin composition according to [7], wherein the alcohol is benzyl alcohol.

[0111] [9] The method for dyeing a resin composition according to [7] or [8], wherein the dye (C) is an acid dye.

[0112]

[10] A synthetic fiber made of the resin composition according to any one of [1] to [6].

[0113]

[11] A method for producing a synthetic fiber, comprising a step of melt-spinning the resin composition according to any one of [1] to [6].

[0114]

[12] A headwear product containing the synthetic fiber described in

[10] .

Claims

1. A resin composition comprising at least a polymer (A) and a polymer (B), the polymer (A) is an acrylic resin, which is a copolymer of acrylonitrile, one or more halogenated monomers selected from the group consisting of vinyl halides and vinylidene halides, and a macromonomer having in its main chain a polymer composed of an ethylenically unsaturated monomer containing a double bond; the polymer (B) is a polymer that dissolves in benzyl alcohol and contains at least one polymer selected from the group consisting of a homopolymer of vinyl acetate, a copolymer of vinylpyrrolidone and vinyl acetate, a copolymer of acrylonitrile and styrene, and poly(glycidyl methacrylate); The resin composition contains 70 parts by mass or more and 92.5 parts by mass or less of the polymer (A) and 7.5 parts by mass or more and 30 parts by mass or less of the polymer (B), where the total amount of the polymer (A) and the polymer (B) is 100 parts by mass.

2. 2. The resin composition according to claim 1, wherein the macromonomer has at least one reactive functional group having a polymerizable carbon-carbon double bond represented by the following general formula (1) at a molecular terminal per molecule: CH 2 =C(R)-C(O)O- (1) (In general formula (1), R represents hydrogen or a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms.)

3. 3. The resin composition according to claim 1, wherein in the macromonomer, the ethylenically unsaturated monomer having a double bond is at least one selected from the group consisting of (meth)acrylic acid ester monomers, styrene monomers, nitrile group-containing vinyl monomers, amide group-containing vinyl monomers, silicon-containing vinyl monomers, maleimide monomers, vinyl esters, alkenes, conjugated dienes, maleic anhydride, maleic acid, monoalkyl esters of maleic acid, dialkyl esters of maleic acid, fumaric acid, monoalkyl esters of fumaric acid, dialkyl esters of fumaric acid, allyl chloride, and allyl alcohol.

4. 4. The resin composition according to claim 1, wherein, in the acrylic resin, when the total mass of the acrylonitrile, the halogenated monomer, and the macromonomer is 100 parts by mass, the content of the acrylonitrile is 35 parts by mass or more and 64 parts by mass or less, the content of the halogenated monomer is 35 parts by mass or more and 64 parts by mass or less, and the content of the macromonomer is 1 part by mass or more and 30 parts by mass or less.

5. The polymer (B) comprises at least one selected from the group consisting of a vinyl acetate homopolymer, a vinylpyrrolidone and vinyl acetate copolymer, and an acrylonitrile and styrene copolymer. The resin composition according to any one of claims 1 to 4.

6. A method for dyeing a resin composition, comprising: permeating the resin composition according to any one of claims 1 to 5 with a dyeing agent containing at least the dye (C) and an alcohol to color the resin composition.

7. The method for dyeing a resin composition according to claim 6, wherein the alcohol is benzyl alcohol.

8. The method for dyeing a resin composition according to claim 6 or 7, wherein the dye (C) is an acid dye.

9. A synthetic fiber made of the resin composition according to any one of claims 1 to 5.

10. A method for producing a synthetic fiber, comprising a step of melt-spinning the resin composition according to any one of claims 1 to 5.

11. A head accessory product comprising at least the synthetic fiber according to claim 9.

12. The head accessory product according to claim 11, wherein the head accessory product comprises one selected from the group consisting of hair wigs, hairpieces, weaving, hair extensions, braided hair, hair accessories, and doll hair.

Images