Solid composition for dyeing keratin

Abstract

To provide a solid composition for dyeing keratin that has high storage stability even when a dye with low alkali stability and a solid alkali agent are mixed and stored.SOLUTION: The present invention relates to a solid composition for dyeing keratin, comprising: a solid alkaline agent having a melting point of 30°C or higher, the surface of which is at least partly coated with a coating material including at least one selected from alcohols, ethers, esters, and hydrocarbons; and a dye.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a solid dyeing composition for keratin, a method for producing the same, and a hair dye kit. [Background technology]

[0002] BACKGROUND ART Hair dyeing methods using oxidation dyes obtained by mixing an agent containing an alkaline agent and an oxidation dye precursor with an oxidizing agent have been disclosed. For example, Patent Document 1 discloses a hair dyeing method comprising the following steps (I) and (II): step (I): mixing a first agent containing an alkaline agent and an oxidation dye precursor, a second agent containing an oxidizing agent, and a third agent containing one or more dyes (A) and having a pH of 7.5 to 12 at 25°C when diluted 10 times by mass with water, and step (II): applying the mixture prepared in step (I) to hair. Furthermore, Patent Document 2 describes a hair dye in which a solid alkalizing agent added to bleaching and dyeing agents for keratin fibers, particularly human hair, is encapsulated in a microparticle core and coated with a fatty acid, lactone, acid anhydride, water-soluble polymer, etc., which inhibits the rapid decomposition of the oxidizing agent when mixed with the oxidizing agent, making it easier to handle and also suppressing the generation of oxygen gas, thereby reducing potential danger. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2019-151615 [Patent Document 2] European Patent No. 1752191 Summary of the Invention [Problem to be solved by the invention]

[0004] However, in the method of Patent Document 1, depending on the type of oxidative dye precursor used, the oxidative dye precursor may decompose upon contact with an alkaline agent during storage, and therefore there are limitations on the type and formulation of the oxidative dye precursor that can be used. Furthermore, the solid alkalizing agent of Patent Document 2 aims to adjust the solubility of the solid alkalizing agent when it is mixed with an oxidizing agent, and since fatty acids, lactones, acid anhydrides, water-soluble polymers, etc. that coat the solid alkalizing agent may dissolve due to moisture in the air during storage, the storage stability of the solid alkalizing agent in contact with the oxidative dye precursor is insufficient. The present invention relates to a solid composition that exhibits excellent storage stability even when stored in a state in which a dye having low alkali stability is mixed with a solid alkaline agent, a method for producing the same, a hair dye kit including the solid composition, and use of the solid composition in cosmetics. [Means for solving the problem]

[0005] The present inventors have found that, in a solid composition for dyeing keratin containing a solid alkaline agent and a dye, a solid composition having excellent storage stability can be provided by coating at least a part of the surface of the solid alkaline agent with a specific coating material. That is, the present invention provides the following: <1> ~ <5> Regarding. <1> A solid composition for dyeing keratin, comprising a solid alkaline agent, at least a portion of whose surface is coated with a coating material containing one or more selected from alcohols, ethers, esters, and hydrocarbons, and having a melting point of 30°C or higher, and a dye. <2> <1> A hair dye kit comprising the solid composition according to claim 1 and a liquid composition containing an oxidizing agent. <3> The method comprises the following steps 1 and 2: <1> A method for producing the solid composition described in claim 1. Step 1: Mixing the molten coating material with the solid alkaline agent to obtain a coating of the solid alkaline agent. Step 2: Mixing the obtained coating with a dye <4> Use in a cosmetic of a solid composition containing a dye and a solid alkaline agent, at least a portion of whose surface is coated with a coating material containing one or more of alcohols, ethers, esters, and hydrocarbons, and having a melting point of 30°C or higher. <5> A method for inhibiting a reaction between a dye and a solid alkaline agent, the method comprising using a solid alkaline agent having at least a portion of its surface coated with a coating material containing one or more selected from the group consisting of alcohols, ethers, esters, and hydrocarbons. [Effects of the Invention]

[0006] According to the present invention, it is possible to provide a solid composition having excellent storage stability and a method for producing the same, as well as a hair dye kit including the solid composition, use of the solid composition in cosmetics, and a method for inhibiting the reaction between a dye and a solid alkaline agent. DETAILED DESCRIPTION OF THE INVENTION

[0007] [Solid dyeing composition for keratin] The solid composition for dyeing keratin of the present invention (hereinafter sometimes simply referred to as the "solid composition") is a solid composition for dyeing keratin at 25°C (1013.25 hPa) containing a solid alkaline agent, at least a portion of whose surface is coated with a coating material containing one or more selected from alcohols, ethers, esters, and hydrocarbons, and having a melting point of 30°C or higher, and a dye. In the solid composition for dyeing keratin of the present invention, the surface of the solid alkaline agent is coated with a coating material, which prevents decomposition of the dye by alkali due to contact with the solid alkaline agent during storage under humid conditions, thereby improving the storage stability (hereinafter also simply referred to as storage stability) of the solid composition. Therefore, it is sufficient that the surface of the solid alkaline agent is coated with a coating material to an extent that improves storage stability. Furthermore, in the solid composition for dyeing keratin of the present invention, the dyeing ability is hardly reduced even though the alkaline agent is coated with a coating material. This is presumably because the adhesion between the relatively hydrophobic coating material and the hydrophilic solid alkaline agent is not so strong that the penetration of the oxidizing agent when it comes into contact with a liquid oxidizing agent for use in dyeing keratin is hardly hindered. The keratin is preferably keratin contained in human hair, and more preferably keratin contained in human hair.

[0008] [Solid alkaline agent] The solid alkaline agent contained in the solid composition has a melting point of 30°C or higher, and its aqueous solution is basic. Examples of solid alkaline agents include inorganic salts such as ammonia salts, alkali metal hydroxides such as sodium hydroxide and potassium hydroxide, metasilicates such as orthosilicates, pyrosilicates, potassium metasilicate, and sodium metasilicate, phosphates such as tripotassium phosphate and trisodium phosphate, and carbonates such as sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, and guanidine carbonate. The salt is preferably a sodium or potassium salt. Among the above solid alkaline agents, one or more selected from orthosilicates, pyrosilicates, metasilicates, phosphates, metadisilicates, carbonates, and hydroxides are preferred, and one or more selected from metasilicates, phosphates, and carbonates are more preferred, with trisodium phosphate and / or sodium metasilicate being even more preferred.

[0009] The average particle size of the solid alkaline agent before coating is preferably 10 μm or more, more preferably 20 μm or more, and even more preferably 30 μm or more from the viewpoint of the storage stability of the solid composition (hereinafter also simply referred to as storage stability), and is preferably 5 mm or less, more preferably 1 mm or less, even more preferably 500 μm or less, and even more preferably 150 μm or less from the viewpoint of dyeability when using the solid composition. The average particle size of the solid alkaline agent is measured by the method described in the Examples.

[0010] The content of the solid alkaline agent in the solid composition is preferably 10% by mass or more, more preferably 15% by mass or more, and even more preferably 20% by mass or more, from the viewpoint of dyeability when using the solid composition, and is preferably 70% by mass or less, more preferably 65% ​​by mass or less, and even more preferably 60% by mass or less, from the viewpoint of storage stability of the solid composition.

[0011] [Covering material] The coating material for coating the solid alkaline agent contains one or more compounds selected from alcohols, ethers, esters, and hydrocarbons. These coating materials may be any compounds selected from alcohols, ethers, esters, and hydrocarbons, or a mixture of two or more compounds, as long as they have a melting point of 30°C or higher. The total content of these compounds in the coating material is preferably 50% by mass or more, more preferably 80% by mass or more, even more preferably 90% by mass or more, and even more preferably 99% by mass or more, and may even be 100% by mass. These compounds may be linear or branched, may have a polyoxyalkylene group attached thereto, and may be alicyclic or aromatic. In general, from the viewpoint of storage stability of the solid composition, the number of carbon atoms in these compounds is preferably 16 or more, more preferably 18 or more, even more preferably 21 or more, even more preferably 25 or more, even more preferably 30 or more, and even more preferably 35 or more, and from the viewpoint of ease of production of the solid composition, the number of carbon atoms is preferably 200 or less, more preferably 100 or less, even more preferably 80 or less, and even more preferably 60 or less. Furthermore, when the coating material is an alcohol, ether, or ester, from the viewpoint of storage stability of the solid composition, it is preferable that the coating material has a monovalent hydrocarbon group having preferably 14 or more carbon atoms, more preferably 16 or more carbon atoms, and even more preferably 18 or more carbon atoms. From the viewpoint of ease of production of the solid composition, it is preferable that the coating material has a monovalent hydrocarbon group having preferably 100 or less carbon atoms, more preferably 60 or less carbon atoms, even more preferably 30 or less carbon atoms, and even more preferably 22 or less carbon atoms. The monovalent hydrocarbon group may be linear or branched. The monovalent hydrocarbon group is preferably a saturated hydrocarbon group. Note that the monovalent hydrocarbon group is a group formed by removing one hydrogen atom from a hydrocarbon, and for example, in the case of the alcohol, it means a hydrocarbon group bonded to a hydroxyl group; in the case of the ether, it means a hydrocarbon group bonded to an oxygen atom; and in the case of the ester, it means a group derived from a carboxylic acid or a group derived from an alcohol. Among these compounds, esters are preferred from the viewpoint of storage stability of the solid composition.Fatty acids are considered undesirable as coating materials because they react with alkaline agents to form soaps, which increase their solubility in water.

[0012] The melting point of the coating material is 30°C or higher, preferably 40°C or higher, more preferably 45°C or higher, even more preferably 50°C or higher, and even more preferably 55°C or higher, from the viewpoint of storage stability of the solid composition, and is preferably 150°C or lower, more preferably 120°C or lower, and even more preferably 90°C or lower, from the viewpoint of ease of production in the coating step when coating the solid alkaline agent.

[0013] The melting point of a coating material is measured using either Method 1, Method 2, or Method 3 of the General Testing Methods for Quasi-drug Ingredients. The method to be used depends primarily on the melting point of the coating material; Method 1 can be used when the melting point is high, exceeding 75°C; Method 2 can be used when the melting point is between 50°C and 75°C; and Method 3 can be used when the melting point is below 50°C. The melting point may also be the value listed in the catalog. To increase the melting point of the coating material to 30°C or higher, the melting point of the compound contained in the coating material should be increased to 30°C or higher.

[0014] From the viewpoint of storage stability, the carbon number of the alcohol used in the coating material is preferably 14 or more, more preferably 16 or more, and even more preferably 18 or more, and from the viewpoint of ease of production, the carbon number is preferably 200 or less, more preferably 100 or less, even more preferably 80 or less, even more preferably 60 or less, even more preferably 30 or less, and even more preferably 22 or less. The alcohol is preferably a straight-chain or branched-chain monohydric alcohol, and specific examples include cetyl alcohol, stearyl alcohol, and behenyl alcohol. From the viewpoint of storage stability, the number of carbon atoms in the ether used in the coating material is preferably 25 or more, more preferably 30 or more, and even more preferably 35 or more, and from the viewpoint of ease of production, it is preferably 200 or less, more preferably 100 or less, even more preferably 80 or less, and even more preferably 60 or less. The ether is preferably a dialkyl ether, and specific examples include distearyl ether. The carbon number of the ester used in the coating material is preferably 25 or more, more preferably 30 or more, and even more preferably 35 or more from the viewpoint of storage stability, and is preferably 200 or less, more preferably 100 or less, even more preferably 80 or less, and even more preferably 60 or less from the viewpoint of ease of production. Examples of raw material alcohols for the esters used in the coating material include monohydric alcohols and polyhydric alcohols such as glycerin, propylene glycol, trimethylolpropane, pentaerythritol, sorbitol, sucrose, etc. The number of carbon atoms in the monohydric alcohol is preferably 1 to 30, more preferably 8 to 30, even more preferably 12 to 22, still more preferably 14 to 22, even more preferably 16 to 22, and still more preferably 18 to 22. Examples of raw carboxylic acids for the esters used in the coating material include monocarboxylic acids, preferably monocarboxylic fatty acids, and polycarboxylic acids such as adipic acid, terephthalic acid, trimellitic acid, etc. The number of carbon atoms in the monocarboxylic acid is preferably 1 to 30, more preferably 8 to 30, even more preferably 12 to 22, still more preferably 14 to 22, even more preferably 16 to 22, and still more preferably 18 to 22. The ester preferably contains one or more selected from fatty acid esters of monohydric fatty acids and monohydric alcohols, fatty acid esters of monohydric fatty acids and polyhydric alcohols, and polycarboxylic acid esters of polycarboxylic acids and monohydric alcohols, and more preferably contains fatty acid esters of monohydric fatty acids and monohydric alcohols and / or fatty acid esters of monohydric fatty acids and polyhydric alcohols. Specific examples of esters of monohydric fatty acids and monohydric alcohols include cetyl palmitate, stearyl stearate, and behenyl behenate, and examples of esters of monohydric fatty acids and polyhydric alcohols include pentaerythritol tetrastearate. The carbon number of the hydrocarbon used in the coating material is, for example, preferably 21 or more, more preferably 25 or more, and even more preferably 30 or more from the viewpoint of storage stability, and from the viewpoint of ease of production, preferably 200 or less, more preferably 100 or less, even more preferably 80 or less, and even more preferably 60 or less. Examples of hydrocarbons used in the coating material include alkanes and paraffins, and specific examples include paraffin wax 140 and paraffin wax 9ND.

[0015] From the viewpoint of storage stability of the solid composition, the coating material is preferably a compound that is poorly soluble in water. Therefore, the solubility of the coating material in 100 g of water at 25° C. (1013.25 hPa) is preferably 100 mg / 100 g or less, more preferably 10 mg / 100 g or less, even more preferably 1 mg / 100 g or less, and even more preferably 0.1 mg / 100 g or less. The lower limit is 0 mg / 100 g (insoluble). For the measurement of solubility, reference can be made to, for example, Journal of the Chemical Society of Japan, 1985, No. 11, pp. 2116-2119 and 1982, No. 11, pp. 1830-1834.

[0016] The mass ratio of the coating material to the mass of the solid alkaline agent (coating material / solid alkaline agent) is preferably 0.01 or more, more preferably 0.05 or more, even more preferably 0.08 or more, and even more preferably 0.15 or more, from the viewpoint of the storage stability of the solid composition, and is preferably 1 or less, more preferably 0.5 or less, and even more preferably 0.3 or less, from the viewpoint of the dyeability when using the solid composition.

[0017] The content of the coating material in the solid composition is preferably 1% by mass or more, more preferably 3% by mass or more, even more preferably 5% by mass or more, and even more preferably 8% by mass or more, from the viewpoint of the storage stability of the solid composition, and is preferably 30% by mass or less, more preferably 20% by mass or less, and even more preferably 15% by mass or less, from the viewpoint of dyeability when using the solid composition. The average particle size of the coated solid alkaline agent is preferably 10 μm or more, more preferably 20 μm or more, and even more preferably 30 μm or more from the viewpoint of storage stability, and is preferably 5 mm or less, more preferably 1 mm or less, and even more preferably 500 μm or less from the viewpoint of dyeability when the solid composition is used. The average particle size of the coated solid alkaline agent is measured by the method described in the Examples.

[0018] 〔dye〕 The dye preferably contains one or more dyes selected from precursors, couplers, and direct dyes, and more preferably contains precursors and couplers, which may be decomposed or otherwise deteriorated in storage stability when in contact with a solid alkaline agent. The dye is preferably solid at 25°C (1013.25 hPa). From the viewpoint of obtaining sufficient dyeability, the content of the dye in the solid composition is preferably 0.03% by mass or more, more preferably 0.05% by mass or more, even more preferably 0.1% by mass or more, and even more preferably 0.3% by mass or more, and from the viewpoint of the storage stability of the solid composition, it is preferably 30% by mass or less, more preferably 20% by mass or less, even more preferably 10% by mass or less, and even more preferably 5% by mass or less.

[0019] (precursor) The precursor, also called an oxidation dye precursor, is oxidized by oxygen generated from an oxidizing agent under the action of an alkaline agent, and reacts with a dye linker such as a coupler described below to generate an oxidation dye. Precursors include paraphenylenediamine compounds such as paraphenylenediamine, orthochloroparaphenylenediamine, N-phenylparaphenylenediamine, N,N-bis(hydroxyethyl)paraphenylenediamine, 2-hydroxyethylparaphenylenediamine, 2-methoxymethylparaphenylenediamine, N-methoxyethyl-paraphenylenediamine, PEG-3,2,2'-paraphenylenediamine, and 2,6-dimethyl-paraphenylenediamine; 3-methyl-4-aminophenol, paraaminophenol, paramethylaminophenol, orthoaminophenol, 2-aminomethyl-4-aminophenol, 2-(2-hydroxyethylaminomethyl)-4-aminophenol; Aminophenol compounds such as 2-amino-5-methylphenol, 2-amino-6-methylphenol, and 2-amino-5-acetamidophenol; 4,4'-diaminodiphenylamine, 1,3-bis(N-(2-hydroxyethyl)-N-(4-aminophenyl)amino)-2-propanol, 3,4-diaminobenzoic acid, 5-aminosalicylic acid, 2,4,5,6-tetraaminopyrimidine, 2,5,6-triamino-4-hydroxypyrimidine, 4,5-diamino-1-(4'-chlorobenzyl)pyrazole, toluene-2,5-diamine, 4-amino-metacresol, hydroxyethoxyaminopyrazolopyridine, 2,3-diaminodihydroxypyrazolopyrazolone, and salts thereof. Among these, the precursor contained in the solid composition of the present invention is preferably one or more selected from phenylenediamine compounds, aminophenol compounds, and salts thereof, more preferably 2-methoxymethyl-paraphenylenediamine, N-methoxyethyl-paraphenylenediamine, paraaminophenol, and salts thereof, and even more preferably 2-methoxymethyl-paraphenylenediamine and salts thereof. Examples of salts include acetates, hydrochlorides, and sulfates.

[0020] The precursors can be used alone or in combination of two or more. The content of the precursor in the solid composition is preferably 0.03% by mass or more, more preferably 0.05% by mass or more, even more preferably 0.1% by mass or more, and even more preferably 0.3% by mass or more, from the viewpoint of obtaining sufficient dyeability, and is preferably 30% by mass or less, more preferably 20% by mass or less, even more preferably 10% by mass or less, and even more preferably 5% by mass or less, from the viewpoint of storage stability of the solid composition.

[0021] (Coupler) Couplers include resorcinol, 2-methylresorcinol, 1-naphthol, 1,5-dihydroxynaphthalene, 5-amino-o-cresol, meta-phenylenediamine, meta-aminophenol, 2,4-diaminophenoxyethanol, 2-methyl-5-amino-6-chlorophenol, 2-amino-4-hydroxyethylaminoanisole, 5-amino-6-chloro-o-cresol, 3-amino-2,4-dichlorophenol, 2,6-diaminopyridine, 2-methyl-5-hydroxyethylaminophenol, 2-Amino-3-hydroxypyridine, para-aminophenol, ortho-aminophenol, 2-amino-4-(2-hydroxyethylamino)anisole, 2,4-diamino-5-methylphenetole, 2,4-diamino-5-(2-hydroxyethoxy)toluene, 2,4-dimethoxy-1,3-diaminobenzene, 2,6-bis(2-hydroxyethylamino)toluene, 2,4-diamino-5-fluorotoluene, 1,3-bis(2,4-diaminophenoxy)propane, 2-methyl-5-aminophenol, 2,4-diamino chloro-3-aminophenol, 2-chloro-3-amino-6-methylphenol, 2-methyl-4-chloro-5-aminophenol, N-cyclopentyl-meta-aminophenol, 2-methyl-4-methoxy-5-(2-hydroxyethylamino)phenol, 2-methyl-4-fluoro-5-aminophenol, 4-chlororesorcinol, 1,7-dihydroxynaphthalene, 2,7-dihydroxynaphthalene, 2-isopropyl-5-methylphenol, 4-hydroxyindole, 5-hydroxyindole, 6-hydroxyindole oxindole, 7-hydroxyindole, 6-hydroxybenzomorpholine, 3,4-methylenedioxyphenol, 2-bromo-4,5-methylenedioxyphenol, 3,4-methylenedioxyaniline, 1-(2-hydroxyethyl)amino-3,4-methylenedioxybenzene, 2,6-dihydroxy-3,4-dimethylpyridine, 2,6-dimethoxy-3,5-diaminopyridine, 2,3-diamino-6-methoxypyridine, 2-methylamino-3-amino-6-methoxypyridine, and salts thereof. Among these, it is preferable to contain at least one selected from aromatic amine compounds having an aromatic amine skeleton with one or more amino groups on the aromatic ring, phenolic compounds having a phenol skeleton with one or more hydroxyl groups on the aromatic ring, pyridine compounds having a pyridine skeleton, and salts thereof. The coupler contained in the solid composition of the present invention is preferably at least one selected from 1,3-bis(2,4-diaminophenoxy)propane, 2-chloro-3-amino-6-methylphenol, 4-chlororesorcinol, 2-methylresorcinol, 2-amino-3-hydroxypyridine, 2,4-diaminophenoxyethanol, 2-methyl-5-amino-6-chlorophenol, 2-amino-4-hydroxyethylaminoanisole, 5-amino-6-chloro-o-cresol, 3-amino-2,4-dichlorophenol, and salts thereof, and more preferably 1,3-bis(2,4-diaminophenoxy)propane, 2-chloro-3-amino-6-methylphenol, or salts thereof. Examples of salts include acetates, hydrochlorides, sulfates, and the like.

[0022] The coupler content in the solid composition is preferably 0.03% by mass or more, more preferably 0.05% by mass or more, even more preferably 0.1% by mass or more, and even more preferably 0.3% by mass or more, from the viewpoint of obtaining sufficient dyeability, and is preferably 30% by mass or less, more preferably 20% by mass or less, even more preferably 10% by mass or less, and even more preferably 5% by mass or less, from the viewpoint of storage stability of the solid composition.

[0023] (direct dye) Examples of direct dyes include azo dyes, anionic dyes, cationic dyes, and neutral dyes. Examples of azo dyes include dyes represented by any of the following structural formulas (A-1), (A-2), and (A-3).

[0024] [ka]

[0025] Examples of anionic dyes include Acid Black 1, Acid Blue 1, Acid Blue 3, Food Blue No. 2, Food Blue No. 5, Acid Blue 7, Acid Blue 9, Acid Blue 74, Acid Orange 3, Acid Orange 6, Acid Orange 7, Acid Orange 10, Acid Red 1, Acid Red 14, Acid Red 18, Acid Red 27, Acid Red 50, Acid Red 52, Acid Red 73, Acid Red 87, Acid Red 88, Acid Red 92, Acid Red 155, Acid Red 180, Acid Purple 9, Acid Purple 43, and Acid Purple 49. , Acid Yellow 1, Acid Yellow 23, Acid Yellow 3, Food Yellow No. 8, Acid Orange 24, Acid Green 25, Solvent Green 7, Solvent Red 73, Acid Red 95, Solvent Red 43, Solvent Red 48, Acid Red 33, Solvent Purple 13, Acid Yellow 73, Food Red No. 17, Food Red No. 1, Food Yellow No. 3, Food Blue No. 2, Food Black No. 1, Food Black No. 2, Dispersed Black 9, Dispersed Purple 1, and their alkali metal salts (sodium salts and potassium salts). Examples of cationic dyes include Basic Blue 6, Basic Blue 7, Basic Blue 9, Basic Blue 26, Basic Blue 41, Basic Blue 99, Basic Brown 4, Basic Brown 16, Basic Brown 17, Natural Brown 7, Basic Green 1, Basic Red 2, Basic Red 12, Basic Red 22, Basic Red 76, Basic Purple 1, Basic Purple 2, Basic Purple 3, Basic Purple 10, Basic Purple 14, Basic Yellow 57, Basic Red 51, Basic Yellow 87, Basic Blue 17, and Basic Orange 31. Neutral dyes including nitro dyes include HC Blue 2, HC Blue 4, HC Blue 5, HC Blue 6, HC Blue 7, HC Blue 8, HC Blue 9, HC Blue 10, HC Blue 11, HC Blue 12, HC Blue 13, HC Brown 1, HC Brown 2, HC Green 1, HC Orange 1, HC Orange 2, HC Orange 3, HC Orange 5, HC Red BN, HC Red. 1, HC Red 3, HC Red 7, HC Red 8, HC Red 9, HC Red 10, HC Red 11, HC Red 13, HC Red 54, HC Red 14, HC Purple BS, HC Purple 1, HC Purple 2, HC Yellow 2, HC Yellow 4, HC Yellow 5, HC Yellow 6, HC Yellow 7, HC Yellow 8, HC Yellow 9, HC Yellow 10, HC Yellow 11, HC Yellow 12 , HC Yellow 13, HC Yellow 14, HC Yellow 15, 2-amino-6-chloro-4-nitrophenol, picramic acid, 1,2-diamino-4-nitrobenzene, 1,4-diamino-2-nitrobenzene, 3-nitro-4-aminophenol, 1-hydroxy-2-amino-3-nitrobenzene, 2-hydroxyethylpicramic acid, 3-nitro-p-hydroxyethylaminophenol, 4-hydroxypropylamino-3-nitrophenol, N,N-bis(2-hydroxyethyl)-2'-nitro-p-phenylenediamine, and the like.

[0026] The direct dyes may be used alone or in combination of two or more. From the viewpoint of obtaining sufficient dyeability, the content of the direct dye in the solid composition is preferably 0.03% by mass or more, more preferably 0.05% by mass or more, even more preferably 0.1% by mass or more, and even more preferably 0.3% by mass or more, and from the viewpoint of storage stability of the solid composition, it is preferably 30% by mass or less, more preferably 20% by mass or less, even more preferably 10% by mass or less, and even more preferably 5% by mass or less.

[0027] The method for coating the solid alkaline agent with the coating material will be described in detail in the section "Method for producing solid composition" below.

[0028] [Other ingredients] The solid composition may contain, in addition to the solid alkali agent and dye, at least a portion of whose surface is coated with the above-mentioned coating material, a surface modifier, a balancing agent, a flow improver, a chelating agent, an oil agent, etc. The storage stability of the solid alkali agent can be improved by further coating the surface of the solid alkali agent coated with a coating material with a surface modifier. Organic powders and inorganic powders are preferred as surface modifiers. Examples of organic powders include monosaccharides and polysaccharides such as glucose, fructose, lactose, maltose, sucrose, dextrin, maltodextrin, cyclodextrin, maltose, fructose, trehalose, cellulose, corn starch, tapioca starch, rice starch, wheat starch, potato starch, erythritol, and mannitol. Examples of inorganic powders include silica, zeolite, bentonite, kaolin, calcium silicate, sodium sulfate, magnesium sulfate, magnesium oxide, zinc oxide, calcium stearate, magnesium stearate, magnesium oxide, sodium polyphosphate, and sodium phosphate. The average particle size of the surface modifier is preferably 100 μm or less, more preferably 50 μm or less, and even more preferably 30 μm or less, from the viewpoint of further coating the surface of the solid alkaline agent coated with the coating material. The mass ratio of the surface modifier to the mass of the solid alkaline agent (surface modifier / solid alkaline agent) is preferably 0.05 or more, more preferably 0.1 or more, and even more preferably 0.15 or more from the viewpoint of the storage stability of the solid composition, and is preferably 1 or less, more preferably 0.5 or less, and even more preferably 0.3 or less from the viewpoint of the dyeability when using the solid composition. Examples of balancing agents include cornstarch. Examples of flow improvers include silica. Examples of chelating agents include ethylenediaminetetraacetic acid (EDTA). Examples of oil agents include liquid oils with a melting point of less than 30°C and isopropyl myristate. When the solid composition of the present invention contains a balancing agent, the content of the balancing agent is preferably 5% by mass or more, more preferably 8% by mass or more, and preferably 75% by mass or less, more preferably 60% by mass or less, from the viewpoint of the storage stability of the solid composition. In the solid composition of the present invention, from the viewpoint of storage stability, the water content is preferably 10% by mass or less, more preferably 3% by mass or less, even more preferably 1% by mass or less, and even more preferably 0.5% by mass or less, and the lower limit is 0% by mass or more, preferably 0.001% by mass or more.

[0029] Solid compositions include powders, briquettes (tablets), etc., with powder compositions being preferred. The average particle size of the powder is the same as the preferred range of the average particle size of the alkaline agent after coating. In the case of compression-molded briquettes (tablets), the maximum length is preferably 1 mm or more, more preferably 3 mm or more, even more preferably 5 mm or more, and preferably 50 mm or less, more preferably 30 mm or less, even more preferably 10 mm or less. The maximum length refers to the number average value of the major diameter (the length of the straight line connecting the most distant points on the surface of the particle) of 50 randomly selected particles observed under an optical microscope. The solid composition of the present invention is preferably a hair dye composition, and more preferably a solid composition for use as a hair dye. [Jar-type container] The solid composition of the present invention is preferably used by storing it in a jar-type container. The jar-type container is preferably a jar-type container that contains the contents and has a bottomed cylindrical or prismatic container body with an opening at the top end, to which a lid is screwed (fitted with a screw). Such a storage container is used by removing the lid and inserting a finger into the container body to directly scoop out the contents, or by using the attached spatula to scoop out the contents. The lid and the main body may be connected by fitting or by a hinge so as to be openable and closable. In a jar-type container, the contents are likely to come into contact with air during use as described above, but the solid composition of the present invention has excellent storage stability even when exposed to moisture in the air, so this does not pose a problem.

[0030] [Hair dye kit] The solid composition of the present invention can be applied as a hair dye kit in which it is packaged separately from a liquid composition containing an oxidizing agent. The mechanism of hair dyeing using a hair dye kit is thought to be as follows. First, the solid alkaline agent and coating material are separated by the external force applied when the solid composition and liquid composition are mixed, and the solid alkaline agent dissolves in the water contained in the liquid composition, producing an alkaline solution. This alkaline solution opens the hair cuticle, allowing the mixture of the solid and liquid compositions to penetrate into the hair. The alkaline solution also reacts with the oxidizing agent to produce oxygen, which bleaches the melanin pigment present in the hair and oxidizes the precursor. The oxidized precursor reacts with a dye linker such as a coupler to produce an oxidative dye, which develops color. The colored oxidative dye molecules polymerize to grow larger, preventing them from escaping through the gaps in the cuticle. The dye is then fixed inside the hair, completing the hair dyeing process. At the same time, the direct dye also penetrates into the hair and develops color.

[0031] The solid composition of the present invention is preferably used for hair dyeing by mixing it with a liquid composition containing an oxidizing agent before application. In the total amount of the solid composition and liquid composition of the present invention, the content of the solid composition of the present invention is preferably 1% by mass or more, more preferably 5% by mass or more, and preferably 20% by mass or less, more preferably 15% by mass or less. Examples of oxidizing agents contained in the liquid composition include peroxides such as hydrogen peroxide, urea peroxide, and melamine peroxide, with hydrogen peroxide being preferred. When hydrogen peroxide is used, the concentration of hydrogen peroxide in the liquid composition is preferably 1% by mass or more, more preferably 2% by mass or more, from the viewpoint of reactivity with the precursor, and is preferably 30% by mass or less, more preferably 20% by mass or less, from the viewpoint of handleability.

[0032] Hair dyeing is preferably carried out at a temperature above room temperature, more preferably above 30° C., and preferably below 45° C. The dyeing time is preferably at least 15 minutes, more preferably at least 25 minutes, and preferably at most 45 minutes, more preferably at most 35 minutes.

[0033] [Method of producing solid composition] The solid composition of the present invention is preferably produced by a production method including the following steps 1 and 2. Step 1: Mixing the molten coating material with a solid alkaline agent to obtain a coating of the solid alkaline agent Step 2: Mixing the resulting coating with a dye

[0034] The coating material can be melted by heating it to a temperature equal to or higher than its melting point. The mass ratio of the coating material to the solid alkaline agent (coating material / solid alkaline agent) is preferably 0.01 or more, more preferably 0.05 or more, even more preferably 0.08 or more, and even more preferably 0.15 or more from the viewpoint of storage stability of the solid composition, and is preferably 1 or less, more preferably 0.5 or less, and even more preferably 0.3 or less from the viewpoint of dyeability when using the solid composition.

[0035] [Use in cosmetics] A solid composition for dyeing keratin, which contains a solid alkaline agent having a melting point of 30°C or higher and at least a portion of its surface coated with a coating material containing one or more selected from alcohols, ethers, esters, and hydrocarbons, and a dye, is preferably used in cosmetics, particularly powder cosmetics. Preferred embodiments of the coating material and the solid alkaline agent are the same as those described above. The solid composition may further contain pigments, antibacterial agents, preservatives, ultraviolet absorbers, fragrances, moisturizing ingredients, and the like. For example, powder cosmetics include makeup cosmetics, hair dyes, perms, treatments and other hair treatment agents, and among these, hair dyes are preferred.

[0036] [Reaction suppression method] By using a solid alkaline agent at least partly coated with a coating material containing one or more selected from alcohols, ethers, esters, and hydrocarbons, it is possible to suppress the deterioration of dyeability due to decomposition of the dye even when the solid alkaline agent comes into contact with the dye. In other words, it is possible to suppress the reaction between the dye and the solid alkaline agent. The preferred embodiments of the coating material and the solid alkaline agent are the same as those described above.

[0037] The present invention provides the following <1> ~ <77> The present invention includes the following aspects. <1> A solid composition for dyeing keratin, comprising a solid alkaline agent, at least a portion of whose surface is coated with a coating material containing one or more selected from alcohols, ethers, esters, and hydrocarbons, and having a melting point of 30°C or higher, and a dye. <2> The melting point of the coating material is 40°C or higher. <1> The solid composition according to claim 1. <3> The melting point of the coating material is 50°C or higher. <1> or <2> The solid composition according to claim 1. <4> The melting point of the coating material is 55°C or higher. <1> ~ <3> 1. The solid composition according to any one of the preceding claims. <5> The melting point of the coating material is 150°C or less. <1> ~ <4> 1. The solid composition according to any one of the preceding claims. <6> The melting point of the coating material is 120°C or less. <1> ~ <5> 1. The solid composition according to any one of the preceding claims. <7> The alcohol comprises a linear or branched monohydric alcohol; <1> ~ <6> 1. The solid composition according to any one of the preceding claims. <8> The ether comprises a dialkyl ether. <1> ~ <7> 1. The solid composition according to any one of the preceding claims. <9> The ester includes at least one selected from a fatty acid ester of a monohydric fatty acid and a monohydric alcohol, a fatty acid ester of a monohydric fatty acid and a polyhydric alcohol, and a polycarboxylic acid ester of a polycarboxylic acid and a monohydric alcohol. <1> ~ <8> 1. The solid composition according to any one of the preceding claims. <10> The ester includes a fatty acid ester of a monohydric fatty acid and a monohydric alcohol and / or a fatty acid ester of a monohydric fatty acid and a polyhydric alcohol. <1> ~ <9> 1. The solid composition according to any one of the preceding claims. <11> The hydrocarbon comprises an alkane or a paraffin; <1> ~ <10> 1. The solid composition according to any one of the preceding claims. <12> the mass ratio of the coating material to the mass of the solid alkaline agent (coating material / solid alkaline agent) is 0.01 or more and 1 or less; <1> ~ <11> 1. The solid composition according to any one of the preceding claims. <13> the mass ratio of the coating material to the mass of the solid alkaline agent (coating material / solid alkaline agent) is 0.05 or more and 0.5 or less; <1> ~ <12> 1. The solid composition according to any one of the preceding claims. <14> the mass ratio of the coating material to the mass of the solid alkaline agent (coating material / solid alkaline agent) is 0.08 or more and 0.3 or less; <1> ~ <13> 1. The solid composition according to any one of the preceding claims. <15> the mass ratio of the coating material to the mass of the solid alkaline agent (coating material / solid alkaline agent) is 0.15 or more and 0.3 or less; <1> ~ <14> 1. The solid composition according to any one of the preceding claims. <16> The solid alkaline agent comprises one or more selected from orthosilicate, pyrosilicate, metasilicate, phosphate, metadisilicate, carbonate, and hydroxide; <1> ~ <15> 1. The solid composition according to any one of the preceding claims. <17> The solid alkaline agent comprises one or more selected from metasilicate, phosphate, and carbonate. <1> ~ <16> 1. The solid composition according to any one of the preceding claims. <18> The solid alkaline agent comprises one or more selected from trisodium phosphate and sodium metasilicate. <1> ~ <17> 1. The solid composition according to any one of the preceding claims. <19> The coating material has a water solubility of 100 mg / 100 g or less at 25°C. <1> ~ <18> 1. The solid composition according to any one of the preceding claims. <20> The coating material has a water solubility of 10 mg / 100 g or less at 25°C. <1> ~ <19> 1. The solid composition according to any one of the preceding claims. <21> The coating material has a water solubility of 1 mg / 100 g or less at 25°C. <1> ~ <20> 1. The solid composition according to any one of the preceding claims. <22> The solubility of the coating material in water at 25°C is 0.1 mg / 100 g or less. <1> ~ <21> 1. The solid composition according to any one of the preceding claims. <23> The compound used in the coating material has 16 or more carbon atoms. <1> ~ <22> 1. The solid composition according to any one of the preceding claims. <24> The compound used in the coating material has 18 or more carbon atoms. <1> ~ <23> 1. The solid composition according to any one of the preceding claims. <25> The compound used in the coating material has 21 or more carbon atoms. <1> ~ <24> 1. The solid composition according to any one of the preceding claims. <26> The compound used in the coating material has 25 or more carbon atoms. <1> ~ <25> 1. The solid composition according to any one of the preceding claims. <27> The compound used in the coating material has 30 or more carbon atoms. <1> ~ <26> 1. The solid composition according to any one of the preceding claims. <28> The compound used in the coating material has a carbon number of 200 or less. <1> ~ <27> 1. The solid composition according to any one of the preceding claims. <29> The compound used in the coating material has a carbon number of 100 or less. <1> ~ <28> 1. The solid composition according to any one of the preceding claims. <30> The compound used in the coating material has a carbon number of 80 or less. <1> ~ <29> 1. The solid composition according to any one of the preceding claims. <31> The compound used in the coating material has a monovalent hydrocarbon group having 14 or more carbon atoms. <1> ~ <22> 1. The solid composition according to any one of the preceding claims. <32> The compound used in the coating material has a monovalent hydrocarbon group having 16 or more carbon atoms. <1> ~ <22> 1. The solid composition according to any one of the preceding claims. <33> The compound used in the coating material has a monovalent hydrocarbon group having 18 or more carbon atoms. <1> ~ <22> 1. The solid composition according to any one of the preceding claims. <34> The compound used in the coating material has a monovalent hydrocarbon group having 60 or less carbon atoms. <1> ~ <22> 1. The solid composition according to any one of the preceding claims. <35> The compound used in the coating material has a monovalent hydrocarbon group having 30 or less carbon atoms. <1> ~ <22> 1. The solid composition according to any one of the preceding claims. <36> The compound used in the coating material has a monovalent hydrocarbon group having 22 or less carbon atoms. <1> ~ <22> 1. The solid composition according to any one of the preceding claims. <37> Further, the surface modifier <1> ~ <36> 1. The solid composition according to any one of the preceding claims. <38> the mass ratio of the surface modifier to the mass of the solid alkaline agent (surface modifier / solid alkaline agent) is 0.05 or more and 1 or less; <37> The solid composition according to claim 1. <39> the mass ratio of the surface modifier to the mass of the solid alkaline agent (surface modifier / solid alkaline agent) is 0.1 or more and 0.5 or less; <37> or <38> The solid composition according to claim 1. <40> The surface modifier is an organic powder or an inorganic powder. <37> ~ <39> 1. The solid composition according to any one of the preceding claims. <41> The organic powder is corn starch. <40> The solid composition according to claim 1. <42> The inorganic powder is silica. <40> The solid composition according to claim 1. <43> The dye comprises one or more selected from a precursor, a coupler, and a direct dye; <1> ~ <42> 1. The solid composition according to any one of the preceding claims. <44> The dye comprises a precursor and a coupler, <43> The solid composition according to claim 1. <45> The precursor comprises at least one selected from the group consisting of phenylenediamine compounds, aminophenol compounds, and salts thereof. <43> or <44> The solid composition according to claim 1. <46> The precursor comprises at least one selected from 2-methoxymethyl-paraphenylenediamine, N-methoxyethyl-paraphenylenediamine, paraaminophenol, and salts thereof. <43> ~ <45> 1. The solid composition according to any one of the preceding claims. <47> the coupler comprises at least one selected from the group consisting of aromatic amine compounds, phenolic compounds, pyridine compounds, and salts thereof; <43> ~ <46> 1. The solid composition according to any one of the preceding claims. <48> the coupler comprises one or more selected from 1,3-bis(2,4-diaminophenoxy)propane, 2-chloro-3-amino-6-methylphenol, 4-chlororesorcinol, 2-methylresorcinol, 2-amino-3-hydroxypyridine, 2,4-diaminophenoxyethanol, 2-methyl-5-amino-6-chlorophenol, 2-amino-4-hydroxyethylaminoanisole, 5-amino-6-chloro-o-cresol, 3-amino-2,4-dichlorophenol, and salts thereof; <43> ~ <47> 1. The solid composition according to any one of the preceding claims. <49> The average particle size of the solid alkaline agent before coating is 10 μm or more and 5 mm or less. <1> ~ <48> 1. The solid composition according to any one of the preceding claims. <50> The average particle size of the solid alkaline agent before coating is 20 μm or more and 1 mm or less. <1> ~ <49> 1. The solid composition according to any one of the preceding claims. <51> The average particle size of the solid alkaline agent before coating is 30 μm or more and 500 μm or less. <1> ~ <50> 1. The solid composition according to any one of the preceding claims. <52> The average particle size of the solid alkaline agent before coating is 30 μm or more and 150 μm or less. <1> ~ <51> 1. The solid composition according to any one of the preceding claims. <53> The average particle size of the coated solid alkaline agent is 10 μm or more and 5 mm or less. <1> ~ <48> 1. The solid composition according to any one of the preceding claims. <54> The average particle size of the coated solid alkaline agent is 20 μm or more and 1 mm or less. <1> ~ <48> 1. The solid composition according to any one of the preceding claims. <55> The average particle size of the solid alkaline agent after coating is 30 μm or more and 500 μm or less. <1> ~ <48> 1. The solid composition according to any one of the preceding claims. <56> In the solid composition, the content of the coating material is 1% by mass or more and 30% by mass or less. <1> ~ <55> 1. The solid composition according to any one of the preceding claims. <57> In the solid composition, the content of the coating material is 3% by mass or more and 20% by mass or less. <1> ~ <56> 1. The solid composition according to any one of the preceding claims. <58> In the solid composition, the content of the coating material is 5% by mass or more and 15% by mass or less. <1> ~ <57> 1. The solid composition according to any one of the preceding claims. <59> The content of the solid alkaline agent in the solid composition is 10% by mass or more and 70% by mass or less. <1> ~ <58> 1. The solid composition according to any one of the preceding claims. <60> The content of the solid alkaline agent in the solid composition is 15% by mass or more and 65% by mass or less. <1> ~ <59> 1. The solid composition according to any one of the preceding claims. <61> The content of the solid alkaline agent in the solid composition is 20% by mass or more and 60% by mass or less. <1> ~ <60> 1. The solid composition according to any one of the preceding claims. <62> The content of the dye in the solid composition is 0.03% by mass or more and 30% by mass or less. <1> ~ <61> 1. The solid composition according to any one of the preceding claims. <63> The content of the dye in the solid composition is 0.05% by mass or more and 20% by mass or less. <1> ~ <62> 1. The solid composition according to any one of the preceding claims. <51> The content of the dye in the solid composition is 0.1% by mass or more and 10% by mass or less. <1> ~ <63> 1. The solid composition according to any one of the preceding claims. <64> The content of the dye in the solid composition is 0.3% by mass or more and 5% by mass or less. <1> ~ <51> 1. The solid composition according to any one of the preceding claims. <65> In the solid composition, the water content is 10% by mass or less. <1> ~ <64> 1. The solid composition according to any one of the preceding claims. <66> In the solid composition, the water content is 1% by mass or less. <1> ~ <65> 1. The solid composition according to any one of the preceding claims. <67> The water content in the solid composition is 0.5% by mass or less. <1> ~ <66> 1. The solid composition according to any one of the preceding claims. <68> A powder composition, <1> ~ <67> 1. The solid composition according to any one of the preceding claims. <69> For hair dyes, <1> ~ <68> 1. The solid composition according to any one of the preceding claims. <70> Packaged in a jar-shaped container, <1> ~ <69> 1. The solid composition according to any one of the preceding claims. <71> <1> ~ <70> 1. A hair dye kit comprising the solid composition according to any one of the above items and a liquid composition containing an oxidizing agent. <72> The oxidizing agent includes hydrogen peroxide. <71> The hair dye kit described herein. <73> The method comprises the following steps 1 and 2: <1> ~ <69> 10. A method for producing the solid composition according to any one of the preceding claims. Step 1: Mixing the molten coating material with the solid alkaline agent to obtain a coating of the solid alkaline agent. Step 2: Mixing the obtained coating with a dye <74> Use in a cosmetic of a solid composition containing a dye and a solid alkaline agent, at least a portion of whose surface is coated with a coating material containing one or more of alcohols, ethers, esters, and hydrocarbons, and having a melting point of 30°C or higher. <75> The cosmetic is a hair treatment agent. <74> Use as described. <76> The cosmetic is a hair dye. <74> or <75> Use as described. <77> A method for inhibiting a reaction between a dye and a solid alkaline agent, the method comprising using a solid alkaline agent having at least a portion of its surface coated with a coating material containing one or more selected from the group consisting of alcohols, ethers, esters, and hydrocarbons. [Example]

[0038] In the following examples and comparative examples, "%" means "% by mass" unless otherwise specified. The physical properties were measured by the following methods.

[0039] [Measurement method] <Average particle size of solid alkaline agents and coated solid alkaline agents> The average particle size of the solid alkaline agent was calculated from the mass distribution of each sieve size after vibrating 100 g of the solid alkaline agent for 5 minutes using a standard sieve (mesh size: 45 to 2000 μm) specified in JIS K 8801-1:2016. More specifically, the powder was vibrated for 5 minutes using sieves of 2000, 1400, 1000, 710, 500, 355, 250, 180, 125, 90, 63, and 45 μm as specified in JIS Z 8801-1:2006 (established May 20, 2000, last revised November 20, 2006), and then the 50% average diameter was calculated for the under-sieve mass distribution by sieving, and this was taken as the average particle size. That is, the above sieves were stacked on a tray in order from the sieve with the smallest opening, 100 g of solid alkali agent was added from the top 2000 μm sieve, the lid was put on, and the sieve was attached to a low-tap type sieve shaker (manufactured by Hirako Manufacturing Co., Ltd., tapping 156 times / min, rolling: 290 times / min), and after vibrating for 5 minutes, the mass of the solid alkali agent remaining on each sieve and tray was measured, and the proportion (mass%) of solid alkali agent on each sieve was calculated. The proportions of solid alkali agent on the sieves with the smallest openings were added up from the tray, and the particle size at which the total was 50 mass% was taken as the average particle size. The average particle size of the coated solid alkaline agent was calculated in the same manner.

[0040] In the production examples, the following raw materials were used. (Solid alkaline agent) Trisodium phosphate: Taihei Chemical Industry Co., Ltd., average particle size 70.7 μm Trisodium phosphate: Yoneyama Chemical Industry Co., Ltd., average particle size 170.3 μm Sodium metasilicate: manufactured by Silmaco NV, average particle size 86.0 μm (covering material) Stearyl stearate: Kao Corporation, product name: Exepar SS, melting point 60°C Behenyl behenate: NOF Corporation, product name: Unistar M-2222SL, melting point 70°C Stearyl alcohol: Kao Corporation, product name: Kalcol 8098, melting point 59°C Behenyl alcohol: Kao Corporation, product name: Kalcol 220-98, melting point 69°C Paraffin Wax-140 (product name): manufactured by Nippon Seiro Co., Ltd., hydrocarbon wax, C n H 2n+2 (n=20-39), melting point 61℃ Paraffin Wax 9ND (product name): manufactured by Nippon Seiro Co., Ltd., hydrocarbon wax, C n H 2n+2 (n=28-52), melting point 75℃ Pentaerythritol tetrastearate: NOF Corporation, product name: WE-476-H, melting point: 62°C Lauryl alcohol: Kao Corporation, product name: Kalcol 2098, melting point 24°C Lauric acid: Kao Corporation, product name: Lunac L-98, titer 43°C Stearic acid: Kao Corporation, product name: Lunac S-98, melting point 69°C (surface modifier) Cornstarch: ROQUETTE FRERES, product name: MAIZE STARCH B (precursor) Precursor A160S: Dragon Chemical (2-methoxymethyl-paraphenylenediamine sulfate) (Coupler) Coupler A79: Extrachem GmbH (1,3-bis(2,4-diaminophenoxy)propane tetrahydrochloride) Coupler A94: Grafox Chemie VERTRIEBS GmbH (2-chloro-3-amino-6-methylphenol) (Other ingredients) Cornstarch: ROQUETTE FRERES, product name: MAIZE STARCH B Silica: EVONIK Industries, product name: SIPERNAT-22 EDTA: Fujifilm Wako Pure Chemical Industries, Ltd., reagent Isopropyl myristate: Fujifilm Wako Pure Chemical Industries, Ltd., reagent

[0041] [Production of solid composition] (Production Example 1) 300 g of trisodium phosphate (particle size: 70 μm) as a solid alkaline agent was added to a 2 L high-speed mixer (Earth Technica Corporation: LFS-2, agitator rotation speed 600 rpm / chopper rotation 1500 rpm / jacket hot water temperature 80°C), and after confirming that the powder temperature had reached 60°C or higher, 33.3 g of molten stearyl stearate as a coating material was added and mixed for 3 minutes, and the mixture was then removed. The resulting mixture was placed in a tray and cooled to 25°C to obtain granules of solid alkaline agent whose surfaces were coated with a coating material. The obtained granules were mixed with the precursors, couplers and other components shown in Table 1 in amounts shown in Table 1, and the mixture was measured into a screw tube to give a solid composition.

[0042] (Manufacturing Examples 2-3) Solid compositions were produced in the same manner as in Production Example 1, except that the content of stearyl stearate was changed as shown in Table 1.

[0043] (Examples 4 to 9) A solid composition was produced in the same manner as in Production Example 1, except that the coating material was changed to one shown in Table 1.

[0044] (Production Example 10) A solid composition was produced in the same manner as in Production Example 1, except that no coating material was used and the content of the balancing agent was changed as shown in Table 1.

[0045] (Production Example 11) A solid composition was produced in the same manner as in Production Example 1, except that stearic acid, a fatty acid, was used as the coating material.

[0046] (Manufacturing Example 12) A solid composition was produced in the same manner as in Production Example 5, except that trisodium phosphate having an average particle size of 170.3 μm was used and the contents of each component were changed as shown in Table 1.

[0047] (Manufacturing Example 13) A solid composition was produced in the same manner as in Production Example 12, except that no coating material was used and the content of the balancing agent was changed as shown in Table 1.

[0048] (Manufacturing Example 14) A solid composition was produced in the same manner as in Production Example 7, except that the amount of precursor was changed to 0.5 parts by mass, 0.8 parts by mass of A79 was used as the coupler, and the content of the balancing agent was changed as shown in Table 1.

[0049] (Manufacturing Example 15) A solid composition was produced in the same manner as in Production Example 14, except that no coating material was used and the content of the balancing agent was changed as shown in Table 1.

[0050] (Manufacturing Example 16) A solid composition was produced in the same manner as in Production Example 5, except that sodium metasilicate was used as the solid alkaline agent and the contents of each component were changed as shown in Table 1.

[0051] (Manufacturing Example 17) 300 g of trisodium phosphate (particle size: 170.3 μm) as a solid alkali agent was added to a 2 L high-speed mixer (Earth Technica Corporation: LFS-2, agitator rotation speed 600 rpm / chopper rotation 1500 rpm / jacket hot water temperature 80 ° C). After confirming that the powder temperature was above 60 ° C, 33.3 g of molten stearyl alcohol as a coating material was added and mixed for 3 minutes. 66.7 g of cornstarch as a surface modifier was added and mixed for 3 minutes, and the mixture was removed. The resulting mixture was placed in a tray and cooled to 25 ° C to obtain granules of solid alkali agent coated with the coating material and surface modifier. The obtained granules were mixed with the precursors, couplers and other components shown in Table 1 in amounts shown in Table 1, and the mixture was measured into a screw tube to give a solid composition.

[0052] [Table 1-1]

[0053] [Table 1-2]

[0054] The results of Production Examples 12 and 17 show that the use of a surface modifier that does not act as a binder can suppress an increase in particle size of the solid composition. This is thought to be because the use of a surface modifier can suppress the adhesion of the solid alkaline agents to each other due to the coating material. Therefore, by combining a coating material and a surface modifier, it is possible to coat the solid alkaline agent and suppress overgranulation during production.

[0055] [Method for evaluating solid compositions] The solid compositions prepared above were stored at 40°C and 25% RH. Humidification was carried out every week from the start of storage under conditions of 25°C, 60% RH, and 16 hours. The following evaluations were carried out two or four weeks after the start of storage. The humidification was carried out once before the evaluation after two weeks, and three times before the evaluation after four weeks.

[0056] The stored solid composition was evaluated by subjecting a tress (goat hair: LB-W) to the following procedure. A liquid composition containing an oxidizing agent was used, with the formulation shown in Table 2. 0.5 g of the solid composition and 4.5 g of the liquid composition (so that the mass ratio of solid composition to liquid composition was 1:9) were accurately weighed into a screw tube and mixed for approximately 10 seconds using a vortex mixer to prepare a paste. A tress was placed on a tray, and 1.5 g of the resulting paste was dropped onto it and carefully applied using a spatula so that the paste was absorbed into the entire hair bundle. After application, the tress was covered with Saran Wrap (registered trademark) and left to stand in an electric dryer at 40°C for 30 minutes. It was then removed from the electric dryer and rinsed with 10 strokes of hot water at 40°C on both sides. After rinsing, the tress was washed with shampoo for 15 seconds and then rinsed again with 10 strokes of hot water at 40°C on both sides. To evaluate dyeability, a spectrophotometer CM-700d manufactured by Konica Minolta, Inc. was used to measure the color of each strand of trace at six points, three on the front and three on the back, and the average value expressed in the L*a*b* color system was calculated. The storage stability of the solid composition was evaluated using the color difference ΔE between the dyeability of the solid composition immediately after production and the dyeability of the solid composition stored for 2 or 4 weeks. The color difference ΔE can be calculated using the following formula (1):

[0057]

number

[0058] In formula (1), ΔL, Δa, and Δb are the differences in the average values ​​calculated from the measured values ​​of the dyeability using a solid composition immediately after production and the dyeability using a solid composition that has been stored for 2 weeks or 4 weeks, respectively. The effect of the solid composition on the dyeability of the coating material was evaluated using the color difference ΔE0 between the dyeability using the solid composition of the Example immediately after production and the solid composition of the Comparative Example immediately after production. The color difference ΔE0 was calculated using the above formula (1), where ΔL, Δa, and Δb are the differences in the average values ​​calculated from the measured values ​​of the dyeability using the solid composition of the Example immediately after production and the dyeability using the solid composition of the Comparative Example immediately after production, respectively. The smaller ΔE0, the smaller the effect on the dyeability of the coating material.

[0059] [Table 2]

[0060] The dyeability of the solid compositions prepared in each Preparation Example was measured according to the method described above. The evaluation criteria were based on the criteria for each coupler used, and the results are shown in Table 3.

[0061] Examples 1 to 10, 12, and 13, and Comparative Examples 1 to 3 The evaluation criteria for Examples 1 to 10, 12, and 13 and Comparative Examples 1 to 3, which used A94 (2-chloro-3-amino-6-methylphenol) as the coupler and trisodium phosphate as the solid alkaline agent, are as follows. If the evaluation result is C or higher, the effects of the present invention are achieved. A: ΔE after 2 weeks of storage is 6 or less, and ΔE after 4 weeks of storage is 10 or less. B: ΔE after 2 weeks of storage is 6 or less, and ΔE after 4 weeks of storage is more than 10 and 16 or less. C: ΔE after 2 weeks of storage is greater than 6 and equal to or less than 8, and ΔE after 4 weeks of storage is equal to or less than 20. D: ΔE after 2 weeks of storage is greater than 8, or ΔE after 4 weeks of storage is greater than 20.

[0062] Example 11 and Comparative Example 4 The evaluation criteria for Example 11 and Comparative Example 4, which used A79 (1,3-bis(2,4-diaminophenoxy)propane) as the coupler and trisodium phosphate as the solid alkaline agent, are as follows. If the evaluation result is C or higher, the effects of the present invention are achieved. A: ΔE after 2 weeks storage and after 4 weeks storage is 5 or less. B: ΔE after 2 weeks of storage is 5 or less, and ΔE after 4 weeks of storage is more than 5 and 7 or less. C: ΔE after 2 weeks of storage is 5 or less, and ΔE after 4 weeks of storage is more than 7 and 9 or less. D: ΔE after 2 weeks of storage is greater than 5.

[0063] [Table 3]

[0064] The evaluation results of the examples and comparative examples show that by coating the surface of the solid alkaline agent with a coating material, the storage stability of the solid composition is improved and the decrease in dyeability is suppressed. Furthermore, it can be seen from the results of Examples 1 to 3 that the storage stability of the solid composition is further improved by increasing the content of the coating material.The results of Examples 1, 4, and 9 show that when an ester is used as the coating material, a high melting point of the ester tends to suppress the storage stability of the solid composition and the decrease in dyeability. The results of Examples 5 and 10 show that the smaller the particle size of the solid alkaline agent, the better the storage stability of the solid composition. When the average particle size of the solid alkaline agent is large, the overall surface area of ​​the solid alkaline agent is small, and therefore the amount of coating material required is reduced. Therefore, in light of the results of Examples 1 to 3, it was thought that the larger the average particle size of the solid alkaline agent, the better the storage stability of the solid composition. However, unexpectedly, the opposite result was obtained. This is thought to be because the larger the average particle size of the solid alkaline agent, the larger the surface area per particle, and the solid alkaline agent is not uniformly coated with the coating material. The results of Examples 5 and 12 show that both trisodium phosphate and sodium metasilicate can be preferably used as solid alkali agents. It is expected that the storage stability will be similarly improved when sodium metasilicate is coated with an ester such as stearyl stearate as a coating material. Since there was almost no difference in the dyeability immediately after production between Examples 1 to 9 and Comparative Example 1, Example 10 and Comparative Example 3, and Example 11 and Comparative Example 4, it was found that coating with a solid alkaline agent surprisingly had almost no effect on the dyeability. In Comparative Example 2, the fatty acid formed a salt (soap) with trisodium phosphate, and therefore the salt of the fatty acid coating the surface of the solid alkaline agent was dissolved by moisture in the air during storage, which is thought to have resulted in poor storage stability of the solid composition. The results of Examples 10 and 13 show that the use of cornstarch as a surface modifier improves storage stability. This is thought to be because the adhesion of powdered cornstarch to the surface of the solid alkaline agent coated with stearyl alcohol enhanced the effect of suppressing contact between the solid alkaline agent and the oxidation dye precursor.

Claims

1. A solid composition for dyeing keratin, containing a solid alkali agent at least partially coated on its surface with a coating material containing one or more selected from alcohols, ethers, esters, and hydrocarbons having a melting point of 30°C or higher, and a dye.

2. The solid composition for dyeing according to claim 1, wherein the mass ratio of the coating material to the mass of the solid alkali agent (coating material / solid alkali agent) is 0.01 or more and 1 or less.

3. The solid composition for dyeing according to claim 1 or 2, wherein the solid alkali agent contains one or more selected from orthosilicates, pyrosilicates, metasilicates, phosphates, metadisilicates, carbonates, and hydroxides.

4. The solid composition for dyeing according to claim 1 or 2, wherein the solubility of the coating material in water is 100 mg / 100 g or less at 25°C.

5. The solid composition for dyeing according to 1 or 2, wherein the carbon number of the compound used for the coating material is 16 or more.

6. The solid composition for dyeing according to 1 or 2, wherein the compound used for the coating material has a monovalent hydrocarbon group having 14 or more carbon atoms.

7. The solid composition for dyeing according to 1 or 2, wherein the dye contains one or more selected from precursors, couplers, and direct dyes.

8. The solid composition for dyeing according to claim 7, wherein the precursor contains one or more selected from phenylenediamine-based compounds, aminophenol-based compounds, and salts thereof.

9. The solid composition for dyeing according to claim 7, wherein the precursor contains one or more selected from 2-methoxymethyl paraphenylenediamine, N-methoxyethyl-paraphenylenediamine, para-aminophenol, and salts thereof.

10. The solid composition for dyeing according to claim 7, wherein the coupler contains one or more selected from aromatic amine compounds, phenolic compounds, pyridine compounds, and salts thereof.

11. The solid composition for dyeing according to claim 7, wherein the coupler contains one or more selected from 1,3-bis(2,4-diaminophenoxy)propane, 2-chloro-3-amino-6-methylphenol, 4-chlororesorcinol, 2-methylresorcinol, 2-amino-3-hydroxypyridine, 2,4-diaminophenoxyethanol, 2-methyl-5-amino-6-chlorophenol, 2-amino-4-hydroxyethylaminoanisole, 5-amino-6-chloro-o-cresol, 3-amino-2,4-dichlorophenol, and salts thereof.

12. The solid composition for dyeing according to claim 1 or 2, wherein the average particle diameter of the solid alkali agent is 10 μm or more and 5 mm or less.

13. The solid composition for dyeing according to claim 1 or 2, wherein the water content in the solid composition is 10% by mass or less.

14. The solid composition for dyeing according to claim 1 or 2, which is a powder composition.

15. The solid composition for dyeing according to claim 1 or 2, which is contained in a jar-type container.

16. A hair dye kit comprising the solid composition for dyeing according to claim 1 or 2 and a liquid composition containing an oxidizing agent.

17. The hair dye kit according to claim 16, wherein the oxidizing agent contains hydrogen peroxide solution.

18. A method for producing the solid composition according to claim 1 or 2, comprising the following steps 1 and 2. Step 1: A step of mixing the melted coating material and the solid alkali agent to obtain a coated product of the solid alkali agent Step 2: A step of mixing the obtained coated product and a dye

19. Use in cosmetics of a solid composition for dyeing, which contains a solid alkali agent at least partially coated on the surface with a coating material containing one or more selected from alcohol, ether, ester, and hydrocarbon and having a melting point of 30 °C or higher, and a dye.

20. The use according to claim 19, wherein the cosmetic is a hair treatment agent.

21. A method for suppressing the reaction between a dye and a solid alkali agent, which uses a solid alkali agent at least partially coated on the surface with a coating material containing one or more selected from alcohol, ether, ester, and hydrocarbon.