First agent for oxidative hair dye, oxidative hair dye, hair dyeing method, and method for suppressing appearance change

Abstract

To provide: a first agent for oxidative hair dye that can suppress temporal appearance change; an oxidative hair dye employing the first agent for oxidative hair dye; a hair dyeing method using the oxidative hair dye; and a method for suppressing appearance change of a composition including an oxidative dye.SOLUTION: There is provided a first agent for oxidative hair dye comprising an oxidative dye and two or more selected from a group consisting of sulfite or a salt thereof, cysteine or a salt thereof, acetylcysteine, cysteine alkyl ester or a salt thereof, thioglycerol or a salt thereof, and cysteamine or a salt thereof. There are also provided: an oxidative hair dye comprising the first agent for oxidative hair dye and a second agent for oxidative hair dye containing an oxidizing agent; and a hair dyeing method using the oxidative hair dye. There is also provided a method for suppressing appearance change of a composition comprising an oxidative dye and two or more selected from a group consisting of sulfite or a salt thereof, cysteine or a salt thereof, acetylcysteine, cysteine alkyl ester or a salt thereof, thioglycerol or a salt thereof, and cysteamine or a salt thereof.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a first agent for an oxidation hair dye, an oxidation hair dye, a hair dyeing method, and a method for suppressing changes in appearance. [Background technology]

[0002] Oxidative hair dyes used to color hair work by dyeing the hair with an oxidative dye that has been permeated into the hair through oxidative polymerization, and achieve longer-lasting color retention in hair compared to other hair coloring agents such as acidic hair dyes.

[0003] As an example of an oxidation hair dye, Patent Document 1 discloses a hair dye composition that uses a mixture of a first agent containing an oxidation dye and an alkaline agent and a second agent containing an oxidizing agent, and that contains (A) a higher alcohol, (B) a hydrolyzed conchiolin solution, and (C) a polyhydric alcohol in the mixture of the first and second agents. This hair dye composition is shown to reduce the reaction odor and lingering fragrance of dyed hair and to reduce color fading upon washing. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2014-240364 Summary of the Invention [Problem to be solved by the invention]

[0005] The oxidative dyes used in oxidative hair dyes tend to deteriorate over time due to oxidation caused by oxygen in the air, etc. When oxidative dyes are blended into compositions such as the first agent for oxidative hair dyes, the oxidative dyes can become discolored or discolored over time, causing changes in the appearance of the composition.

[0006] Compositions containing oxidation dyes, such as the first agent for oxidation hair dyes, may be stored for long periods before use. Therefore, in terms of improving quality, it is desirable to suppress changes in the appearance of the composition that occur over time, such as coloring.

[0007] The present invention aims to provide a first agent for an oxidative hair dye that can suppress changes in appearance over time, an oxidative hair dye using the first agent for the oxidative hair dye, and a hair dyeing method using the oxidative hair dye. Another object of the present invention is to provide a method for suppressing changes in appearance over time of a composition containing an oxidative dye. [Means for solving the problem]

[0008] In light of the above-mentioned object, the present inventors have conducted extensive research to inhibit changes in appearance of compositions such as the first agent of an oxidative hair dye that occur when an oxidative dye is incorporated. As a result, the present inventors have found that by incorporating an oxidative dye in a composition such as the first agent of an oxidative hair dye in combination with two or more selected from sulfurous acid or a salt thereof, cysteine or a salt thereof, acetylcysteine or a salt thereof, cysteine alkyl ester or a salt thereof, thioglycerin or a salt thereof, and cysteamine or a salt thereof, the changes in appearance of the composition over time can be inhibited.

[0009] The present invention includes the following inventions [1] to

[10] . [1] A first agent for an oxidation hair dye containing an oxidation dye and two or more selected from sulfurous acid or its salt, cysteine or its salt, acetylcysteine or its salt, cysteine alkyl ester or its salt, thioglycerin or its salt, and cysteamine or its salt.

[0010] [2] The first agent for an oxidation hair dye according to [1], wherein the oxidation dye contains at least one or more selected from 2,4-diaminophenoxyethanol or a salt thereof, and 5-aminoorthocresol or a salt thereof.

[0011] [3] As the two or more selected from the group consisting of sulfurous acid or a salt thereof, cysteine or a salt thereof, acetylcysteine or a salt thereof, cysteine alkyl ester or a salt thereof, thioglycerin or a salt thereof, and cysteamine or a salt thereof, A combination of at least the following (a) to (e): The first agent for the oxidative hair dye according to [1] or [2]. (a) A combination of one or more selected from sulfurous acid or a salt thereof and one or more selected from cysteine or a salt thereof (b) A combination of one or more selected from sulfurous acid or its salts and one or more selected from thioglycerin or its salts. (c) A combination of one or more selected from sulfurous acid or its salts and one or more selected from cysteamine or its salts. (d) A combination of one or more selected from cysteine or a salt thereof and one or more selected from cysteamine or a salt thereof (e) A combination of one or more selected from thioglycerin or a salt thereof and one or more selected from cysteamine or a salt thereof

[0012] [4] The first agent for the oxidative hair dye according to any one of [1] to [3], which is liquid.

[0013] [5] Oxidative dyes, and two or more selected from sulfurous acid or a salt thereof, cysteine or a salt thereof, acetylcysteine or a salt thereof, cysteine alkyl ester or a salt thereof, thioglycerin or a salt thereof, and cysteamine or a salt thereof; The first agent for oxidative hair dyes containing A second agent for oxidative hair dye containing an oxidizing agent, Oxidative hair dye with

[0014] [6] The oxidation hair dye according to [5], wherein the oxidation dye contains at least one or more selected from 2,4-diaminophenoxyethanol or a salt thereof, and 5-aminoorthocresol or a salt thereof.

[0015] [7] The oxidative hair dye according to [5] or [6], wherein the two or more selected from sulfurous acid or a salt thereof, cysteine or a salt thereof, acetylcysteine or a salt thereof, cysteine alkyl ester or a salt thereof, thioglycerin or a salt thereof, and cysteamine or a salt thereof are at least a combination selected from the following (a) to (e): (a) A combination of one or more selected from sulfurous acid or a salt thereof and one or more selected from cysteine or a salt thereof (b) A combination of one or more selected from sulfurous acid or its salts and one or more selected from thioglycerin or its salts. (c) A combination of one or more selected from sulfurous acid or its salts and one or more selected from cysteamine or its salts. (d) A combination of one or more selected from cysteine or a salt thereof and one or more selected from cysteamine or a salt thereof (e) A combination of one or more selected from thioglycerin or a salt thereof and one or more selected from cysteamine or a salt thereof

[0016] [8] The oxidation hair dye according to any one of [5] to [7], wherein the first agent for the oxidation hair dye is liquid.

[0017] [9] A hair dyeing method using the oxidative hair dye according to any one of [5] to [8] above.

[0018]

[10] A method for suppressing changes in appearance of a composition containing an oxidative dye, the composition containing an oxidative dye and two or more selected from sulfurous acid or a salt thereof, cysteine or a salt thereof, acetylcysteine or a salt thereof, cysteine alkyl ester or a salt thereof, thioglycerin or a salt thereof, and cysteamine or a salt thereof. [Effects of the Invention]

[0019] According to the first agent for an oxidation hair dye of the present invention, it is possible to provide a first agent for an oxidation hair dye that is inhibited from changing in appearance over time. According to the oxidation hair dye of the present invention, an oxidation hair dye containing a first agent for an oxidation hair dye that suppresses changes in appearance over time can be provided. According to the hair dyeing method of the present invention, a hair dyeing method using the oxidation hair dye of the present invention can be provided. According to the method for suppressing changes in appearance of the present invention, a method for suppressing changes in appearance over time in a composition containing an oxidation dye can be provided. DETAILED DESCRIPTION OF THE INVENTION

[0020] The present invention will be described below based on an embodiment of the present invention (hereinafter referred to as "the present embodiment").

[0021] <1. First agent for oxidation hair dye> The first agent for the oxidative hair dye of this embodiment (hereinafter sometimes referred to as "the first agent of this embodiment") contains an oxidative dye and two or more selected from sulfurous acid or a salt thereof, cysteine or a salt thereof, acetylcysteine or a salt thereof, cysteine alkyl ester or a salt thereof, thioglycerin or a salt thereof, and cysteamine or a salt thereof.

[0022] [Oxidation dyes] The first agent of this embodiment contains one or more oxidation dyes. Examples of the oxidation dyes include dye intermediates and couplers.

[0023] (dye intermediates) Examples of the dye intermediates include paraphenylenediamine or a salt thereof (for example, hydrochloride, sulfate, etc.), N-phenylparaphenylenediamine or a salt thereof (for example, hydrochloride, acetate, etc.), orthochloroparaphenylenediamine or a salt thereof (for example, sulfate, etc.), orthoaminophenol or a salt thereof (for example, sulfate, etc.), paraaminophenol or a salt thereof (for example, sulfate, hydrochloride, etc.), paramethylaminophenol or a salt thereof (for example, sulfate, etc.), toluene-2,5-diamine or a salt thereof (for example, hydrochloride, sulfate, etc.), toluene-3,4-diamine or and salts thereof (for example, hydrochloride, sulfate, etc.), 1-amino-4-methylaminoanthraquinone, 1,4-diaminoanthraquinone, 1-hydroxyethyl-4,5-diaminopyrazole or salts thereof (for example, sulfate, etc.), 2,2'-[(4-aminophenyl)imino]bisethanol or salts thereof (for example, sulfate, etc.), 2,4-diaminophenol or salts thereof (for example, hydrochloride, sulfate, etc.), 4,4'-diaminodiphenylamine or salts thereof (for example, sulfate, etc.), and N,N'-bis(4-aminophenyl)-2,5-diamino-1,4-quinone diimine.

[0024] In order to achieve highly saturated dyeing of hair, the first agent of this embodiment preferably contains an oxidative dye containing toluene-2,5-diamine or a salt thereof, paraaminophenol or a salt thereof, 1-hydroxyethyl-4,5-diaminopyrazole or a salt thereof, or 2,2'-[(4-aminophenyl)imino]bisethanol or a salt thereof.

[0025] The blending amount of the dye intermediate in the first agent of this embodiment is, for example, 0.001% by mass or more and 2.5% by mass or less.

[0026] (coupler) Examples of the coupler include resorcinol, 2-methylresorcinol, 2-chlororesorcinol, 4-chlororesorcinol, 5-amino-o-cresol or a salt thereof (e.g., sulfate, etc.), meta-aminophenol or a salt thereof (e.g., sulfate, etc.), meta-phenylenediamine or a salt thereof (e.g., hydrochloride, etc.), 1,5-dihydroxynaphthalene, 2,4-diaminophenoxyethanol or a salt thereof (e.g., hydrochloride, etc.), 3,3′-iminodiphenol, 5-(2-hydroxyethylamino)-2-methylphenol, α-naphthol, and 2,6-diaminopyridine.

[0027] The amount of coupler in the first agent of this embodiment is, for example, 0.001% by mass or more and 2.5% by mass or less.

[0028] In this embodiment, the molar ratio of the total amount of dye intermediates in the first agent to the total amount of couplers in the first agent is, for example, 1:0.5 to 2, and from the viewpoint of more sufficiently carrying out oxidative polymerization of the dye intermediates and couplers, it is preferably 1:0.7 to 1.5, and more preferably 1:0.8 to 1.2.

[0029] The blending amount of the oxidative dye in the first agent of this embodiment may be, for example, 0.001% by mass or more and 9% by mass or less, or 0.001% by mass or more and 5% by mass or less.

[0030] The first agent of this embodiment may contain at least one oxidative dye selected from 2,4-diaminophenoxyethanol or a salt thereof, and 5-aminoorthocresol or a salt thereof. As shown in the Reference Examples below, compositions containing 2,4-diaminophenoxyethanol or a salt thereof, and 5-aminoorthocresol or a salt thereof tend to be more susceptible to changes in appearance over time than other couplers. However, the first agent of this embodiment can suppress changes in appearance over time even when using 2,4-diaminophenoxyethanol or a salt thereof, and 5-aminoorthocresol or a salt thereof as oxidative dyes.

[0031] The first agent of this embodiment may also contain, as oxidation dyes, one or more selected from toluene-2,5-diamine or a salt thereof, para-aminophenol or a salt thereof, 1-hydroxyethyl-4,5-diaminopyrazole or a salt thereof, and 2,2'-[(4-aminophenyl)imino]bisethanol or a salt thereof, combined with one or more selected from 2,4-diaminophenoxyethanol or a salt thereof, and 5-aminoorthocresol or a salt thereof. By combining these specific dye intermediates with couplers, even when 2,4-diaminophenoxyethanol or a salt thereof, and 5-aminoorthocresol or a salt thereof are used, changes in appearance over time can be suppressed and highly saturated dyeing of hair can be achieved.

[0032] [two or more selected from sulfurous acid or its salt, cysteine or its salt, acetylcysteine or its salt, cysteine alkyl ester or its salt, thioglycerin or its salt, and cysteamine or its salt] The first agent of this embodiment contains two or more selected from sulfurous acid or its salt, cysteine or its salt, acetylcysteine or its salt, cysteine alkyl ester or its salt, thioglycerin or its salt, and cysteamine or its salt (hereinafter, sometimes referred to as "two or more selected from sulfurous acid, etc."). Here, "containing two or more selected from sulfurous acid, etc." means containing two or more selected from "sulfurous acid or its salt," "cysteine or its salt," "acetylcysteine or its salt," "cysteine alkyl ester or its salt," "thioglycerin or its salt," and "cysteamine or its salt."

[0033] The first agent of this embodiment may be a blend of two or more selected from sulfurous acid or a salt thereof, cysteine or a salt thereof, acetylcysteine or a salt thereof, cysteine alkyl ester or a salt thereof, thioglycerin or a salt thereof, and cysteamine or a salt thereof.

[0034] (sulfurous acid or its salts) Examples of the sulfurous acid or a salt thereof include sulfurous acid, sodium sulfite, potassium sulfite, ammonium sulfite, monoethanolamine sulfite, sodium hydrogen sulfite, and ammonium hydrogen sulfite.

[0035] (Cysteine or its salts) Examples of the cysteine or a salt thereof include L-cysteine, DL-cysteine, L-cysteine hydrochloride, and DL-cysteine hydrochloride.

[0036] (Acetylcysteine or its salts) Examples of the acetylcysteine or a salt thereof include N-acetyl-L-cysteine, N-acetyl-DL-cysteine, sodium salt of N-acetyl-L-cysteine, and potassium salt of N-acetyl-L-cysteine.

[0037] (Cysteine alkyl ester or its salt) Examples of the cysteine alkyl ester or a salt thereof include L-cysteine methyl ester, L-cysteine ethyl ester, L-cysteine methyl ester hydrochloride, and L-cysteine ethyl ester hydrochloride. The alkyl group in the cysteine alkyl ester has, for example, 1 to 4 carbon atoms.

[0038] (Thioglycerin or its salts) The thioglycerin or a salt thereof includes, for example, thioglycerin (also known as 1-thioglycerol).

[0039] (Cysteamine or its salts) Examples of the cysteamine or a salt thereof include cysteamine and cysteamine hydrochloride.

[0040] In order to suppress changes in appearance over time and to suppress deterioration of hair dyeability over time, the first agent of this embodiment preferably contains at least one combination selected from the following (a) to (e) as two or more types selected from sulfites and the like, and more preferably contains one combination of (a), (b), (d), and (e). (a) A combination of one or more selected from sulfurous acid or a salt thereof and one or more selected from cysteine or a salt thereof (b) A combination of one or more selected from sulfurous acid or its salts and one or more selected from thioglycerin or its salts. (c) A combination of one or more selected from sulfurous acid or its salts and one or more selected from cysteamine or its salts. (d) A combination of one or more selected from cysteine or a salt thereof and one or more selected from cysteamine or a salt thereof (e) A combination of one or more selected from thioglycerin or a salt thereof and one or more selected from cysteamine or a salt thereof

[0041] The blending amount of two or more selected from sulfurous acid and the like in the first agent of this embodiment can be set appropriately, for example, from 0.01% by mass to 5% by mass.

[0042] The amount of two or more selected from sulfurous acid and the like in the first agent of this embodiment is preferably 0.1% by mass or more, and more preferably 0.3% by mass or more, from the viewpoint of making it possible to more easily achieve a change in appearance over time in the first agent of this embodiment. Furthermore, the amount of two or more selected from sulfurous acid and the like in the first agent of this embodiment is preferably 3% by mass or less, and more preferably 1% by mass or less, from the viewpoint of reducing the characteristic odor derived from components such as sulfurous acid and its salts in the first agent.

[0043] In the first agent of this embodiment, the mass ratio of the amount of the oxidative dye to the amount of two or more selected from sulfurous acid and the like can be set appropriately, and is, for example, 0.01 or more and 10 or less.

[0044] [Optional ingredients] In addition to the components described above, the first agent of this embodiment can contain other optional components as appropriate. These optional components can be any known components that can be incorporated into first agents for oxidation hair dyes, such as alkaline agents, cationic surfactants, nonionic surfactants, anionic surfactants, higher alcohols, hydrocarbons, fats and oils, polyhydric alcohols, antioxidants, chelating agents, oxidation dyes, direct dyes, and water.

[0045] (Alkaline agent) The first agent of the present embodiment may contain one or more alkaline agents, which can swell the hair and improve the penetration of the oxidative dye into the hair.

[0046] Examples of the alkaline agent include metal hydroxides such as sodium hydroxide and potassium hydroxide, metal carbonates such as sodium carbonate and potassium carbonate, metal phosphates such as sodium phosphate, ammonia, ammonium salts such as ammonium carbonate and ammonium sulfate, alkanolamines such as monoethanolamine, triethanolamine, isopropanolamine, and 2-amino-2-methyl-1-propanol, etc. The alkaline agent incorporated in the first agent may also contain an alkanolamine.

[0047] The amount of alkaline agent contained in the first agent of this embodiment is not particularly limited and can be set as appropriate.

[0048] The amount of alkaline agent in the first agent of this embodiment is preferably 0.01% by mass or more, more preferably 0.1% by mass or more, from the viewpoint of achieving a deeper dyeing of the hair, and is preferably 10% by mass or less, more preferably 3% by mass or less, and even more preferably 1% by mass or less, from the viewpoint of further preventing hair damage during the hair dyeing treatment.

[0049] (water) The first agent of this embodiment may optionally contain water as a solvent for the oxidative dye. The amount of water in the first agent of this embodiment is appropriately determined, but is, for example, 30% by mass or more and 90% by mass or less.

[0050] (cationic surfactant) The first agent of this embodiment may optionally contain one or more cationic surfactants that can be incorporated into cosmetics or quasi-drugs. Examples of cationic surfactants include long-chain alkyl trimethyl ammonium salts, di-long-chain alkyl dimethyl ammonium salts, tri-long-chain alkyl monomethyl ammonium salts, benzalkonium-type quaternary ammonium salts, and monoalkyl ether-type quaternary ammonium salts. The amount of cationic surfactant incorporated in the first agent of this embodiment may be appropriately determined, but is, for example, 0.1% by mass or more and 10% by mass or less.

[0051] (nonionic surfactant) The first agent of this embodiment may optionally contain one or more nonionic surfactants that can be incorporated into cosmetics or quasi-drugs. Examples of nonionic surfactants include polyoxyethylene alkyl ethers, polyoxyethylene polyoxypropylene alkyl ethers, polyoxypropylene alkyl ethers, polyoxyethylene fatty acid esters, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene sorbitol tetra fatty acid esters, glycerin fatty acid esters, sorbitan fatty acid esters, polyglycerin fatty acid esters, and sucrose fatty acid esters. The amount of nonionic surfactant in the first agent of this embodiment may be appropriately determined, but is, for example, 0.1% by mass or more and 10% by mass or less.

[0052] The first agent of this embodiment may optionally contain one or more anionic surfactants that can be incorporated into cosmetics or quasi-drugs. Examples of anionic surfactants that can be used include anionic surfactants having a hydrocarbon group with 8 to 24 carbon atoms. Examples of the anionic surfactants include carboxylic acid-based anionic surfactants (e.g., polyoxyethylene alkyl ether carboxylic acid or its salt, N-acyl amino acid or its salt, fatty acid amide ether carboxylic acid or its salt, acyl lactic acid or its salt, higher fatty acid salt, etc.), sulfonic acid-based anionic surfactants (e.g., α-olefin sulfonic acid or its salt (e.g., sodium olefin (C14-16) sulfonate), alkanesulfonic acid or its salt, α-sulfofatty acid methyl ester or its salt, acyl isethionic acid or its salt, alkyl glycidyl ether sulfonic acid or its salt, alkyl sulfosuccinic acid or its salt, alkyl sulfoacetic acid or its salt, alkyl benzene Examples of anionic surfactants include sulfonic acids or salts thereof, alkyl naphthalene sulfonic acids or salts thereof, sulfate-based anionic surfactants (e.g., alkyl sulfates or salts thereof, alkyl ether sulfates or salts thereof, alkyl aryl ether sulfates or salts thereof, fatty acid alkanolamide sulfates or salts thereof, and fatty acid monoglyceride sulfates or salts thereof), and phosphate-based anionic surfactants (e.g., alkyl phosphates or salts thereof (dicetyl phosphate, etc.), alkyl ether phosphates or salts thereof (polyoxyethylene cetyl ether phosphate (10 E.O.), polyoxyethylene cetyl ether phosphate (20 E.O.), etc.), alkyl aryl ether phosphates or salts thereof, and fatty acid amide ether phosphates or salts thereof). Examples of the salts include sodium salts, potassium salts, triethanolamine salts, and magnesium salts. The amount of the anionic surfactant in the hair dye composition of this embodiment can be appropriately determined, but is, for example, 1% by mass or more and 20% by mass or less.

[0053] (higher alcohol) The first agent of this embodiment may optionally contain one or more higher alcohols that can be incorporated into cosmetics or quasi-drugs. Examples of higher alcohols that can be used include monohydric alcohols having 12 to 24 carbon atoms. Specific examples of higher alcohols include linear higher alcohols such as myristyl alcohol, cetanol, oleyl alcohol, stearyl alcohol, and behenyl alcohol, and branched higher alcohols such as isocetyl alcohol, octyldodecanol, and isostearyl alcohol. The amount of higher alcohol incorporated in the first agent of this embodiment may be appropriately determined, but is, for example, 1% by mass or more and 20% by mass or less.

[0054] (Polyhydric alcohol) The first agent of this embodiment may optionally contain one or more polyhydric alcohols that can be incorporated into cosmetics or quasi-drugs. Examples of polyhydric alcohols include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, glycerin, diglycerin, and butylene glycol. The amount of polyhydric alcohol incorporated in the first agent of this embodiment may be appropriately determined, but is, for example, 0.1% by mass or more and 20% by mass or less.

[0055] (hydrocarbons) The first agent of this embodiment may optionally contain one or more hydrocarbons that can be incorporated into cosmetics or quasi-drugs. Examples of hydrocarbons include liquid paraffin, squalane, pristane, ozokerite, paraffin, ceresin, petrolatum, and microcrystalline wax. The amount of hydrocarbon incorporated into the first agent of this embodiment may be appropriately determined, but is, for example, 0.1% by mass or more and 10% by mass or less.

[0056] (Oils and fats) The first agent of this embodiment may optionally contain one or more types of fats and oils that can be incorporated into cosmetics or quasi-drugs. Examples of fats and oils include hydrogenated oil, almond oil, avocado oil, olive oil, shea butter oil, evening primrose oil, camellia oil, peanut oil, and rosehip oil. The amount of fat and oil incorporated into the first agent of this embodiment may be appropriately determined, but is, for example, 0.1% by mass or more and 10% by mass or less.

[0057] (Ascorbic acid or its salts) The first agent of this embodiment may contain ascorbic acid or a salt thereof. By incorporating ascorbic acid or a salt thereof into the first agent of this embodiment, the rate of the oxidative polymerization reaction of the oxidative dye can be controlled during hair dyeing with the oxidative hair dye using the first agent of this embodiment. The amount of ascorbic acid or a salt thereof in the first agent of this embodiment is appropriately determined, but may be, for example, 0.01% by mass or more and 0.9% by mass or less, or 0.01% by mass or more and 0.5% by mass or less.

[0058] [viscosity] The viscosity of the first agent in this embodiment is set as appropriate, but is, for example, 1 mPa·s or more and 50,000 mPa·s or less. Here, the viscosity of the first agent in this embodiment is the value measured after 60 seconds at 25°C using a Brookfield viscometer with a rotor selected according to the viscosity. The rotor rotation speed during measurement is preferably, for example, 12 rpm.

[0059] When the first agent of this embodiment is liquid, the viscosity is, for example, 5000 mPa·s or less.

[0060] [pH] The pH of the first agent of this embodiment is set appropriately, for example, to 7.5 or higher, but from the viewpoint of achieving highly saturated dyeing of hair while reducing the risk of hair damage in an oxidative hair dye using the first agent of this embodiment, it is preferably 7.0 to 12.0, more preferably 7.5 to 11.5. The pH is measured at 25°C using a known pH meter (the same applies in the following description).

[0061] [Alkalinity] The alkalinity of the first agent of this embodiment is set as appropriate, but is, for example, 0.1 or more and 15.0 or less. Here, "alkalinity" refers to the volume of 0.1 mol / L hydrochloric acid required to neutralize 1 g of the first agent for the oxidation hair dye (unit of alkalinity: ml). The alkalinity can be adjusted using the above-mentioned alkaline agent.

[0062] [Dosage form] The dosage form of the first agent of this embodiment may be appropriately determined. Examples of dosage forms include liquid, cream, gel, and powder. The dosage form of the first agent of this embodiment is preferably liquid, from the viewpoint of reducing the viscosity of the oxidation hair dye and facilitating uniform application to hair.

[0063] [container] The first agent of this embodiment may be contained in a known container used for the first agent of an oxidation hair dye. Examples of the container include a bottle container and a tube container. The material of the container is not particularly limited, and examples include inorganic materials such as resin and glass, and composites of resin or glass with other materials. Examples of the resin include polyethylene terephthalate (PET), high-density polyethylene, low-density polyethylene, polypropylene (CPP), biaxially oriented polypropylene (OPP), polyvinylidene chloride (PVDC), ethylene-vinyl acetate copolymer (EVA), polycarbonate (PO), polyvinyl chloride (PVC), nylon (NY), ethylene-vinyl alcohol copolymer (EVOH), and polyvinyl alcohol (PVA).

[0064] The first agent of this embodiment may be contained in, for example, a resin container (such as PET). Containers made of resin such as PET have relatively high gas permeability (gas barrier properties) compared to glass containers, but the first agent of this embodiment can suppress changes in appearance over time even when contained in a resin container such as PET.

[0065] [Manufacturing method] The method for producing the first agent of this embodiment can employ known production methods for first agents for oxidation hair dyes.

[0066] [How to use] The first agent of this embodiment can be used to obtain an oxidation hair dye by mixing it with a second agent for an oxidation hair dye containing an oxidizing agent.

[0067] <2. Oxidative hair dye> The oxidative hair dye of this embodiment comprises at least a first agent for oxidative hair dye and a second agent for oxidative hair dye. The oxidative hair dye of this embodiment is prepared by mixing the first agent for oxidative hair dye and the second agent for oxidative hair dye in appropriate amounts, and then applying the mixture to hair to dye the hair.

[0068] The oxidative hair dye of this embodiment may comprise a first agent for oxidative hair dyes, a second agent for oxidative hair dyes, and other agents (such as a third agent for oxidative hair dyes) containing ingredients that can be blended in oxidative hair dyes. When the oxidative hair dye of this embodiment comprises other agents, the first agent for oxidative hair dyes, the second agent for oxidative hair dyes, and the other agents are mixed in appropriate amounts, and then the mixture is applied to the hair for a hair dyeing treatment to dye the hair.

[0069] [First agent for oxidation hair dyes] The first agent for the oxidative hair dye of the present embodiment contains an oxidative dye and two or more selected from sulfurous acid or a salt thereof, cysteine or a salt thereof, acetylcysteine, cysteine alkyl ester or a salt thereof, thioglycerin or a salt thereof, and cysteamine or a salt thereof.

[0070] The first agent for the oxidative hair dye of the present embodiment can be the same as the first agent of the present embodiment described above in <1. First agent for oxidative hair dye>. The details of the "oxidative dye" and "two or more selected from sulfurous acid or a salt thereof, cysteine or a salt thereof, acetylcysteine, cysteine alkyl ester or a salt thereof, thioglycerin or a salt thereof, and cysteamine or a salt thereof" blended in the first agent for the oxidative hair dye of the present embodiment are the same as those of the first agent of the present embodiment described above.

[0071] The optional ingredients, viscosity, pH, alkalinity, formulation, container, and production method of the first agent for the oxidative hair dye of this embodiment are the same as those of the first agent of this embodiment described above.

[0072] [Second agent for oxidation hair dyes] The second agent for the oxidation hair dye according to the oxidation hair dye of this embodiment (hereinafter, sometimes referred to as "the second agent of this embodiment") contains an oxidizing agent.

[0073] (oxidizing agent) The second agent of this embodiment contains one or more oxidizing agents, which act to promote oxidative polymerization of the oxidative dye contained in the oxidative hair dye through an oxidation reaction.

[0074] Examples of the oxidizing agent include hydrogen peroxide, bromate, percarbonate, and perborate. As the oxidizing agent, hydrogen peroxide is preferred from the viewpoint of its superior bleaching effect on hair (bleaching effect of melanin pigment in hair).

[0075] The amount of oxidizing agent blended in the second agent of this embodiment is not particularly limited and can be set appropriately, but is, for example, 0.1% by mass or more and 8% by mass or less.

[0076] The blending amount of the oxidizing agent in the second agent of this embodiment is preferably 0.5% by mass or more, more preferably 1.0% by mass or more, more preferably 1.5% by mass or more, and even more preferably 2.0% by mass or more, from the viewpoint of more excellent bleaching effect on hair. Furthermore, the blending amount of the oxidizing agent in the second agent of this embodiment is preferably 7.0% by mass or less, more preferably 6.0% by mass or less, from the viewpoint of further preventing hair damage during hair dyeing treatment.

[0077] [Optional ingredients] The second agent of this embodiment may contain optional components other than the oxidizing agent, as appropriate. The optional components may be any known components that can be contained in the second agent for oxidation hair dyes, such as nonionic surfactants, higher alcohols, hydrocarbons, oils and fats, polyhydric alcohols, antioxidants, chelating agents, and water.

[0078] (nonionic surfactant) The second agent of this embodiment may optionally contain one or more nonionic surfactants that can be incorporated into cosmetics or quasi-drugs. The types of nonionic surfactants used in the second agent of this embodiment are the same as those used in the first agent of this embodiment. The amount of nonionic surfactant in the second agent of this embodiment is appropriately determined, but is, for example, 0.1% by mass or more and 10% by mass or less.

[0079] (higher alcohol) The second agent of this embodiment may optionally contain one or more higher alcohols that can be blended into cosmetics or quasi-drugs. The types of higher alcohols used in the second agent of this embodiment are the same as those used in the first agent of this embodiment. The amount of higher alcohol blended in the second agent of this embodiment is set appropriately, but is, for example, 0.1% by mass or more and 10% by mass or less.

[0080] (water) The second agent of this embodiment may optionally contain water. The amount of water contained in the second agent of this embodiment may be appropriately determined, but is, for example, 50% by mass or more and 98% by mass or less.

[0081] [viscosity] The viscosity of the second part of this embodiment is set as appropriate, but is, for example, 1 mPa·s or more and 20,000 mPa·s or less. Here, the viscosity of the second part of this embodiment is the value measured after 60 seconds at 25°C using a Brookfield viscometer with a rotor selected according to the viscosity. The rotor rotation speed during measurement is preferably, for example, 12 rpm.

[0082] When the second agent of this embodiment is liquid, the viscosity is, for example, 5000 mPa·s or less.

[0083] [pH] The pH of the second agent of this embodiment is set as appropriate, but is, for example, 0.5 or higher. When hydrogen peroxide is blended into the second agent, the pH of the second agent for the oxidative hair dye according to this embodiment is preferably 0.8 or higher, and more preferably 1.0 or higher, from the viewpoint of further improving the storage stability of the hydrogen peroxide blended in the second agent. Furthermore, the pH of the second agent of this embodiment is preferably 3.0 or less, and more preferably 2.5 or less, from the viewpoint of further reducing hair damage during hair dye treatment.

[0084] [Dosage form] The dosage form of the second agent of this embodiment may be appropriately determined. Examples of dosage forms include liquid, cream, gel, and powder. The dosage form of the second agent of this embodiment is preferably liquid, from the viewpoint of reducing the viscosity of the oxidation hair dye and facilitating uniform application to hair.

[0085] The second agent of this embodiment can be produced by employing a known production method for the second agent for an oxidation hair dye.

[0086] [Manufacturing method] The oxidative hair dye of this embodiment can be produced by mixing appropriate amounts of the first agent for the oxidative hair dye of this embodiment and the second agent for the oxidative hair dye of this embodiment.

[0087] [viscosity] The viscosity of the oxidative hair dye of this embodiment is set as appropriate, but may be, for example, 1 mPa·s or more and 30,000 mPa·s or less, or 5,000 mPa·s or more and 15,000 mPa·s or less. Here, the viscosity of the oxidative hair dye of this embodiment is the value measured after 60 seconds at 25°C using a Brookfield viscometer with a rotor selected according to the viscosity. The rotor rotation speed during measurement is preferably, for example, 12 rpm.

[0088] [pH] The pH of the oxidative hair dye of this embodiment is set appropriately, for example, to 7.5 or higher, but from the viewpoint of achieving highly saturated dyeing of hair while reducing the risk of hair damage, it is preferably 8.0 or higher and 12.0 or lower, and more preferably 8.5 or higher and 11.5 or lower.

[0089] [How to use] The oxidative hair dye of this embodiment can be used in a known manner for oxidative hair dyes. For example, the oxidative hair dye of this embodiment can be used by mixing appropriate amounts of a first agent for the oxidative hair dye of this embodiment and a second agent for the oxidative hair dye of this embodiment to obtain an oxidative hair dye (the mixing ratio of the first agent to the second agent may be, for example, First Agent:Second Agent = 1 part by mass:0.5 to 3 parts by mass, or First Agent:Second Agent = 1 part by mass:0.5 to 1.5 parts by mass), applying the oxidative hair dye to wet or dry hair, leaving it to stand for a predetermined time (for example, 5 minutes to 30 minutes; from the viewpoint of sufficient hair dyeing, a leaving time of 10 minutes to 30 minutes is preferable), rinsing, drying the hair, and then dyeing the hair.

[0090] [Hair type suitable for oxidative hair dye] The target hair to be treated with the oxidative hair dye of this embodiment is not particularly limited, and can be hair that has a history of being dyed with an oxidative hair dye, or hair that has not a history of being dyed with an oxidative hair dye.

[0091] <3. Hair dyeing method using oxidative hair dye> The hair dyeing method of the present embodiment is a hair dyeing method using the oxidative hair dye of the present embodiment.

[0092] The hair dyeing method of this embodiment may employ any known hair dyeing method for oxidative hair dyes, except for using the oxidative hair dye of this embodiment. The hair dyeing method of this embodiment is not particularly limited, but may include, for example, mixing appropriate amounts of a first agent for an oxidative hair dye and a second agent for an oxidative hair dye to obtain an oxidative hair dye (the mixing ratio of the first agent to the second agent may be, for example, First Agent:Second Agent = 1 part by mass:0.5 to 3 parts by mass, or First Agent:Second Agent = 1 part by mass:0.5 to 1.5 parts by mass), applying the oxidative hair dye to wet or dry hair, leaving it for a predetermined time (for example, 5 to 30 minutes; from the viewpoint of sufficient hair dyeing, a leaving time of 10 to 30 minutes is preferable), rinsing, drying the hair, and then dyeing the hair.

[0093] <4. Method for suppressing changes in appearance of a composition containing an oxidation dye> The method for suppressing a change in appearance of this embodiment (hereinafter sometimes referred to as the "suppression method of this embodiment") is a method for suppressing a change in appearance of a composition containing an oxidative dye, in which the composition contains an oxidative dye and two or more selected from sulfurous acid or a salt thereof, cysteine or a salt thereof, acetylcysteine, a cysteine alkyl ester or a salt thereof, thioglycerin or a salt thereof, and cysteamine or a salt thereof.

[0094] The details of the "oxidative dye" and "two or more selected from sulfurous acid or a salt thereof, cysteine or a salt thereof, acetylcysteine, cysteine alkyl ester or a salt thereof, thioglycerin or a salt thereof, and cysteamine or a salt thereof" incorporated into the composition in the suppression method of this embodiment are the same as those described above for the first agent of this embodiment.

[0095] The composition containing the oxidation dye in the inhibition method of this embodiment is not particularly limited in its use, but can be used, for example, as a first agent for an oxidation hair dye. [Example]

[0096] The present invention will be described in detail below based on examples, but the present invention should not be construed as being limited by the descriptions in these examples.

[0097] (Production of First Agents for Oxidative Hair Dye Agents of Examples 1 to 6, Comparative Examples 1 to 3, and Reference Examples 1 to 3) First agents for oxidation hair dyes of Examples 1 to 6, Comparative Examples 1 to 3, and Reference Examples 1 to 3 were produced by mixing ingredients selected from 2,5-toluenediamine sulfate, 2,4-diaminophenoxyethanol hydrochloride, 5-aminoorthocresol, meta-aminophenol, resorcinol, 2-methylresorcinol, 4-chlororesorcinol, sodium sulfite, L-cysteine, thioglycerin, cysteamine hydrochloride, monoethanolamine, sodium hydroxide, ascorbic acid, tetrasodium hydroxyethanediphosphonate, and purified water in a conventional manner to obtain the compositions shown in Tables 1 to 3. Each of the first agents for oxidation hair dyes produced was in liquid form, and had a pH in the range of 9 to 10.

[0098] In Tables 1 to 3, the numerical values in the ingredient columns are % by mass, and "-" indicates that the ingredient is not blended. Here, in Tables 1 and 2, the "appropriate amount" of sodium hydroxide in Examples 3, 4, and 6 and Comparative Example 2 refers to the amount blended so that the pH of the first agent for the oxidative hair dye becomes 9.2. Furthermore, in Tables 1 to 3, the "amount that makes the total 100" of purified water refers to the amount blended so that the amount of purified water in the first agent for the oxidative hair dye, together with the ingredients other than purified water, becomes 100% by mass.

[0099] Also, a second agent for an oxidation hair dye having the composition described below was prepared by mixing the components in a conventional manner.

[0100] (Second agent for oxidation hair dye) Hydrogen peroxide 2% by mass Phosphoric acid 0.21% by mass Purified water 97.79% by mass

[0101] (Evaluation method) As shown below, the suppression of appearance change and ΔEab* after storage at 60°C for 4 weeks were evaluated.

[0102] (Suppression of appearance changes after storage at 60°C for 4 weeks) Two PET sealed bottles (black; capacity: 60 mL) were prepared and each bottle was filled with 60 g of the first agent for the oxidative hair dye of Example 1 to prepare two test samples. For one of the test samples, a sufficient amount of nitrogen gas (N2) was blown into the space between the contents and the mouth of the sealed bottle when the bottle was upright, and the bottle was then sealed. The test sample with nitrogen gas blown into it was designated the test sample for storage at -2°C. Next, the other test sample was sealed without blowing nitrogen gas into the space between the contents and the mouth of the sealed bottle when the bottle was upright. The test sample without nitrogen gas blown into it was designated the test sample for storage at 60°C. Subsequently, for the first agents for the oxidative hair dye of Examples 2 to 6, Comparative Examples 1 to 3, and Reference Examples 1 to 3, test samples for storage at -2°C and test samples for storage at 60°C were prepared in the same manner as above.

[0103] Next, each test sample for storage at -2°C was placed in a thermostatic bath adjusted to a temperature of -2°C, and each test sample for storage at 60°C was placed in a thermostatic bath adjusted to a temperature of 60°C, and each was left to stand for four weeks. After four weeks had passed, each test sample was removed from each thermostatic bath and left to stand for a while until the contents (first agents for each oxidation hair dye) contained in each test sample reached room temperature. After each test sample had stood at room temperature, each test sample for storage at -2°C and each test sample for storage at 60°C were placed in a transparent beaker, respectively. Next, the appearance of the first agents for oxidation hair dyes of Comparative Example 2 after storage at -2°C and after storage at 60°C was compared, and the change in appearance (degree of coloration) after storage at 60°C was used as a reference. The changes in appearance of each of the first agents for oxidation hair dyes of Examples 1 to 6, Comparative Examples 1 and 3, and Reference Examples 1 to 3 after storage at -2°C and 60°C were visually observed.

[0104] The inhibition of change in appearance after 4 weeks of storage at 60° C. was evaluated according to the following evaluation criteria: After storage at −2° C., the appearance of the first agent for the oxidation hair dye of Comparative Example 2 was only slightly yellow (transparent), but after storage at 60° C., the appearance of the first agent for the oxidation hair dye of Comparative Example 2 was more yellow (transparent) than after storage at −2° C.

[0105] (Evaluation criteria) ○○○: The appearance of the first agent for the oxidative hair dye after storage at 60°C is almost the same as the appearance of the first agent for the oxidative hair dye after storage at -2°C, and is much better at suppressing appearance changes than the standard (appearance changes (degree of coloring) in the first agent for the oxidative hair dye of Comparative Example 2). ○○: The appearance of the first agent for the oxidative hair dye after storage at 60°C is slightly discolored compared to the appearance of the first agent for the oxidative hair dye after storage at -2°C, but the change in appearance is smaller than the standard (change in appearance (degree of discoloration) in the first agent for the oxidative hair dye of Comparative Example 2), and the suppression of change in appearance is quite excellent. ○: The appearance of the first agent for the oxidative hair dye after storage at 60°C is discolored compared to the appearance of the first agent for the oxidative hair dye after storage at -2°C, but the change in appearance is slightly smaller than the standard (change in appearance (degree of discoloration) in the first agent for the oxidative hair dye of Comparative Example 2), and the suppression of change in appearance is excellent. Similar: The appearance of the first agent for the oxidative hair dye after storage at 60°C is slightly discolored compared to the appearance of the first agent for the oxidative hair dye after storage at -2°C, and the degree of discoloration is similar to the standard (change in appearance (degree of discoloration) in the first agent for the oxidative hair dye of Comparative Example 2). ×: The appearance of the first agent for the oxidative hair dye after storage at 60°C was significantly more discolored than the appearance of the first agent for the oxidative hair dye after storage at -2°C, and the change in appearance was slightly greater than the standard (change in appearance (degree of discoloration) in the first agent for the oxidative hair dye of Comparative Example 2), indicating poor suppression of change in appearance. XX: The appearance of the first agent for the oxidative hair dye after storage at 60°C was discolored to a black or dark brown color compared to the appearance of the first agent for the oxidative hair dye after storage at -2°C, and the change in appearance was greater than the standard (change in appearance (degree of discoloration) in the first agent for the oxidative hair dye of Comparative Example 2), indicating very poor suppression of appearance change.

[0106] (ΔEab* after 4 weeks storage at 60°C) After evaluating the suppression of appearance change, the following hair dyeing treatment was carried out using the first agent for each oxidative hair dye stored at -2°C and the first agent for each oxidative hair dye stored at 60°C, which were placed in beakers. 23 g of the first agent for each oxidative hair dye stored at -2°C or 60°C and 23 g of the second agent for the oxidative hair dye prepared above were added to a transparent PET bottle (50 ml) and mixed to obtain oxidative hair dyes using the first agents for the oxidative hair dyes of Examples 1 to 6, Comparative Examples 1 to 3, and Reference Examples 1 to 3 stored at -2°C or 60°C. Next, a strand of yak hair (manufactured by Beaulux, yak hair: product name BM-YK-A, length 10 cm) was placed in each bottle containing the oxidative hair dye. Next, each bottle was placed in a thermostatic shaker (LAB-THERMO SHAKER TS-20, SHAKER CONTROL setting 7, temperature setting 25°C), and the hair bundle was dyed while being shaken for 20 minutes. After dyeing, the hair bundle was washed for 1 minute using approximately 0.5 g of Grand Linkage Willow Luxe Shampoo (manufactured by Milbon Co., Ltd.), rinsed with running water, and then dried with a hair dryer.

[0107] Next, a*, b*, and L* of each hair bundle dyed with the oxidative hair dye containing the first agent for the oxidative hair dye of Example 1 after storage at 60°C or -2°C were measured using a color difference meter (Konica Minolta, spectrophotometric colorimeter CM-5). Δa*, Δb*, and ΔL* were calculated according to the following formula using the a*, b*, and L* values of the hair bundle dyed with each test sample after storage at 60°C (represented as a*(60°C), b*(60°C), and L*(60°C), respectively) and the a*, b*, and L* values of the hair bundle dyed with each test sample after storage at -2°C (represented as a*(-2°C), b*(-2°C), and L*(-2°C), respectively).

[0108] Δa*=a*(60℃)-a*(-2℃) Δb*=b*(60℃)-b*(-2℃) ΔL*=L*(60℃)-L*(-2℃)

[0109] Subsequently, ΔEab* was calculated using the values of Δa*, Δb*, and ΔL* according to the following formula.

[0110] ΔEab*=√{(Δa*) 2 +(Δb*) 2 +(ΔL*) 2}

[0111] In the same manner as above, ΔEab* was calculated for the oxidation hair dyes using the first agents for oxidation hair dyes of Examples 2 to 6, Comparative Examples 1 to 3, and Reference Examples 1 to 3 after storage at 60°C or -2°C.

[0112] Here, the smaller the ΔEab* value, the less difference there is in the dyeing results of hair strands dyed with the oxidative hair dye using the first agent for the oxidative hair dye stored at 60°C and the first agent for the oxidative hair dye stored at -2°C, indicating that the deterioration of hair dyeability over time is more effectively suppressed.

[0113] (Evaluation results) Tables 1 to 3 below show the evaluation results of the first agents for oxidation hair dyes of Examples 1 to 6, Comparative Examples 1 to 3, and Reference Examples 1 to 3.

[0114] (Evaluation results of Examples 1 to 4 and Comparative Examples 1 to 3) Table 1 shows the evaluation results for the first agents for oxidation hair dyes of Examples 1 to 4 and Comparative Examples 1 to 3.

[0115] [Table 1]

[0116] The results shown in Table 1 show that the first agents for the oxidative hair dyes of Examples 1 to 4 were superior in suppressing changes in appearance over time compared to the first agents for the oxidative hair dyes of Comparative Examples 1 to 3. Therefore, it can be seen that the first agents for the oxidative hair dyes of Examples 1 to 4 are superior in suppressing changes in appearance over time.

[0117] Furthermore, as shown in Table 1, the ΔEab* values of the oxidative hair dyes using the first agents for oxidative hair dyes of Examples 1 to 4 were smaller than the ΔEab* values of the oxidative hair dyes using the first agents for oxidative hair dyes of Comparative Examples 1 to 3. Therefore, it can be seen that the oxidative hair dyes using the first agents for oxidative hair dyes of Examples 1 to 4 are able to suppress the deterioration of hair dyeing properties over time.

[0118] The first agent for the oxidative hair dye of Example 1, which contains sodium sulfite and L-cysteine, was evaluated as superior in terms of inhibition of appearance change and had a smaller ΔEab* value than the first agents for the oxidative hair dye of Comparative Example 1 or Comparative Example 2, which contain sodium sulfite or L-cysteine, indicating that a synergistic effect is exhibited by the combined use of sodium sulfite and L-cysteine.Furthermore, the first agents for the oxidative hair dye of Examples 2 and 3, which contain sodium sulfite and thioglycerin or cysteamine hydrochloride, were evaluated as superior in terms of inhibition of appearance change and had a smaller ΔEab* value than the first agent for the oxidative hair dye of Comparative Example 2, which contains sodium sulfite, indicating that a synergistic effect is exhibited by the combined use of sodium sulfite and thioglycerin or cysteamine hydrochloride. Furthermore, the first agent for the oxidative hair dye of Example 4, which contained L-cysteine and cysteamine hydrochloride, was evaluated as superior in terms of suppressing changes in appearance and had a smaller ΔEab* value than the first agent for the oxidative hair dye of Comparative Example 2, which contained sodium sulfite, indicating that the combined use of L-cysteine and cysteamine hydrochloride exhibits a synergistic effect.

[0119] (Evaluation Results of Examples 5 and 6) Table 2 shows the evaluation results for the first agents for the oxidation hair dyes of Examples 5 and 6.

[0120] [Table 2]

[0121] The results shown in Table 2 show that the first agents for the oxidative hair dye of Examples 5 and 6 were superior in suppressing changes in appearance over time compared to the first agent for the oxidative hair dye of Comparative Example 2 in Table 1. Therefore, it can be seen that the first agents for the oxidative hair dye of Examples 5 and 6 are superior in suppressing changes in appearance over time.

[0122] Furthermore, as shown in Table 2, the ΔEab* value for the oxidative hair dye using the first agent for the oxidative hair dye of Example 6 was smaller than the ΔEab* values for the oxidative hair dye using the first agents for the oxidative hair dye of Comparative Examples 1 to 3 in Table 1. Therefore, it can be seen that the oxidative hair dye using the first agent for the oxidative hair dye of Example 6 is able to suppress the deterioration of hair dyeing properties over time compared to the oxidative hair dye using the first agents for the oxidative hair dye of Comparative Examples 1 to 3.

[0123] (Evaluation Results of Reference Examples 1 to 6) Table 3 shows the evaluation results for the first agents for the oxidation hair dyes of Reference Examples 1 to 6.

[0124] [Table 3]

[0125] The results shown in Table 3 show that the first agents for the oxidative hair dye of Reference Examples 1 to 6 were inferior to the first agent for the oxidative hair dye of Comparative Example 2 in Table 1 in terms of suppressing changes in appearance over time.

[0126] The first agents for oxidative hair dyes in Reference Examples 1 to 6 contain different types of couplers among the oxidative dyes. However, as shown in Table 3, the ΔEab* values for the oxidative hair dyes containing the first agents for oxidative hair dyes in Reference Examples 3 to 6 were smaller than the ΔEab* values for the oxidative hair dyes containing the first agents for oxidative hair dyes in Reference Examples 1 and 2. This indicates that the degree of deterioration in hair dyeing properties over time varies depending on the type of coupler used. Furthermore, the results in Table 3 show that the first agents for oxidative hair dyes in Reference Examples 1 and 2, which contained 2,4-diaminophenoxyethanol hydrochloride or 5-aminoorthocresol, had higher ΔEab* values than the first agents for oxidative hair dyes in Reference Examples 3 to 6, which contained other couplers. This indicates that 2,4-diaminophenoxyethanol hydrochloride and 5-aminoorthocresol are oxidative dyes that are prone to deterioration in hair dyeing properties over time.

[0127] Here, the oxidative hair dyes using the first agents for oxidative hair dyes of Examples 1 to 4 and 6 shown in Tables 1 and 2 contain 2,4-diaminophenoxyethanol hydrochloride and 5-aminoorthocresol, which tend to cause a decrease in hair dyeing ability over time, but they had smaller ΔEab* values than the first agents for oxidative hair dyes of Comparative Examples 1 to 3. Therefore, it can be seen that the oxidative hair dyes using the first agents for oxidative hair dyes of Examples 1 to 4 and 6 are able to strongly suppress the decrease in hair dyeing ability over time of these oxidative dyes, even though they contain 2,4-diaminophenoxyethanol hydrochloride and 5-aminoorthocresol, which tend to cause a decrease in hair dyeing ability over time.

[0128] (Prescription example) Formulation examples 1 and 2 are shown below.

[0129] (Formulation example 1: Oxidative hair dye) First agent for oxidation hair dye (cream type) Toluene-2,5-diamine sulfate 0.1% by mass 2,4-diaminophenoxyethanol hydrochloride 0.05% by mass 5-amino orthocresol 0.05% by mass Polyoxyethylene behenyl ether (5E.O.) 1% by mass Polyoxyethylene cetyl ether (30E.O.) 2% by weight Lipophilic glyceryl monostearate 0.5% by mass Paraffin 3% by mass Stearyl alcohol 10% by mass Polyethylene glycol 1000 3% by mass Cetyltrimethylammonium chloride 1% by mass Propylene glycol 1% by mass Sodium sulfite 0.2% by mass L-cysteine 0.2% by mass Thioglycerin 0.1% by mass Cysteamine hydrochloride 0.1% by mass L-ascorbic acid 0.2% by mass Disodium edetate 0.3% by mass Cationized cellulose 0.1% by mass 25% ammonia water 6% by mass Ammonium bicarbonate 1% by mass Purified water 70.1% by mass Second agent for oxidation hair dye (cream type) Cetyl alcohol 3% by mass Stearyl alcohol 2% by mass Polyoxyethylene cetyl ether (30E.O.) 1% by mass Hydroxyethanediphosphonic acid 0.05% by mass Phenoxyethanol 0.05% by mass Hydrogen peroxide 6% by mass Phosphoric acid 2% by mass Purified water 85.9% by mass

[0130] (Formulation example 2: Oxidative hair dye) First agent for oxidation hair dye (liquid) Toluene-2,5-diamine sulfate 0.1% by mass 2,4-diaminophenoxyethanol hydrochloride 0.05% by mass 5-amino orthocresol 0.05% by mass (C12-14) Palace-3 5% by mass Polyoxyethylene lauryl ether (3E.O.) 5% by mass Olefin (C14-16) Sodium Sulfonate 10% by mass Oleyl alcohol 10% by mass Propylene glycol 10% by mass Sodium sulfite 0.2% by mass L-cysteine 0.2% by mass Thioglycerin 0.1% by mass Cysteamine hydrochloride 0.1% by mass Ascorbic acid 0.3% by mass Isopropanol 5% by mass Monoethanolamine 1% by mass Tetrasodium hydroxyethanediphosphonate 0.1% by mass Purified water 52.8% by mass Second agent for oxidation hair dye (liquid) Hydrogen peroxide 2% by mass Phosphoric acid 0.2% by mass Sodium edetate 0.1% by mass Purified water 97.7% by mass

Claims

1. Oxidative dyes, and two or more selected from sulfurous acid or a salt thereof, cysteine or a salt thereof, acetylcysteine or a salt thereof, cysteine alkyl ester or a salt thereof, thioglycerin or a salt thereof, and cysteamine or a salt thereof; The first agent for oxidative hair dyes containing

2. 2. The first agent for an oxidation hair dye according to claim 1, wherein the oxidation dye contains at least one or more selected from 2,4-diaminophenoxyethanol or a salt thereof, and 5-aminoorthocresol or a salt thereof.

3. the two or more selected from sulfurous acid or a salt thereof, cysteine or a salt thereof, acetylcysteine or a salt thereof, cysteine alkyl ester or a salt thereof, thioglycerin or a salt thereof, and cysteamine or a salt thereof; At least one of the following combinations (a) to (e) is blended: The first agent for an oxidation hair dye according to claim 1 or 2. (a) A combination of one or more selected from sulfurous acid or a salt thereof and one or more selected from cysteine or a salt thereof (b) A combination of one or more selected from sulfurous acid or its salts and one or more selected from thioglycerin or its salts. (c) A combination of one or more selected from sulfurous acid or a salt thereof and one or more selected from cysteamine or a salt thereof. (d) A combination of one or more selected from cysteine or a salt thereof and one or more selected from cysteamine or a salt thereof. (e) A combination of one or more selected from thioglycerin or a salt thereof and one or more selected from cysteamine or a salt thereof.

4. The first agent for an oxidation hair dye according to claim 1 or 2, which is liquid.

5. Oxidative dyes, and two or more selected from sulfurous acid or a salt thereof, cysteine or a salt thereof, acetylcysteine or a salt thereof, cysteine alkyl ester or a salt thereof, thioglycerin or a salt thereof, and cysteamine or a salt thereof; A first agent for an oxidation hair dye containing a second agent for an oxidation hair dye containing an oxidizing agent; Oxidative hair dye with

6. 6. The oxidation hair dye according to claim 5, wherein the oxidation dye contains at least one or more selected from 2,4-diaminophenoxyethanol or a salt thereof, and 5-aminoorthocresol or a salt thereof.

7. 7. The oxidation hair dye according to claim 5, wherein the two or more selected from sulfurous acid or a salt thereof, cysteine or a salt thereof, acetylcysteine or a salt thereof, cysteine alkyl ester or a salt thereof, thioglycerin or a salt thereof, and cysteamine or a salt thereof are at least any combination selected from the following (a) to (e): (a) A combination of one or more selected from sulfurous acid or a salt thereof and one or more selected from cysteine or a salt thereof (b) A combination of one or more selected from sulfurous acid or its salts and one or more selected from thioglycerin or its salts. (c) A combination of one or more selected from sulfurous acid or a salt thereof and one or more selected from cysteamine or a salt thereof. (d) A combination of one or more selected from cysteine or a salt thereof and one or more selected from cysteamine or a salt thereof. (e) A combination of one or more selected from thioglycerin or a salt thereof and one or more selected from cysteamine or a salt thereof.

8. The first agent for an oxidation hair dye according to claim 5 or 6, wherein the first agent for an oxidation hair dye is liquid.

9. A hair dyeing method using the oxidative hair dye composition according to claim 5 or 6.

10. A method for suppressing changes in appearance of a composition containing an oxidative dye, the composition containing an oxidative dye and two or more selected from sulfurous acid or a salt thereof, cysteine or a salt thereof, acetylcysteine or a salt thereof, cysteine alkyl ester or a salt thereof, thioglycerin or a salt thereof, and cysteamine or a salt thereof.

Images