Oxidative hair dye

Abstract

To provide an oxidative hair dye containing a 4,5-diamino pyrazole derivative, which has high chroma while maintaining hair dying power, and is also capable of preventing color migration.SOLUTION: An oxidative hair dye contains (A) a coupler, and (B) a compound represented by general formula (1). The content of the (A) coupler is 0.3 mass% or more. The mass ratio (B / A) of the compound represented by general formula (1) to the (A) coupler is 0.5 or less (where, R denotes a C1-6 linear or branched alkyl group, a C2-6 linear or branched mono- or poly-hydroxyalkyl group, or a linear or branched mono- or poly-aminoalkyl group).SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to an oxidative hair dye containing a 4,5-diaminopyrazole derivative and a coupler.

Background Art

[0002] For example, an oxidative hair dye composed of a first agent containing an alkaline agent and an oxidation dye and a second agent containing an oxidizing agent such as hydrogen peroxide is known. The alkaline agent promotes the action of the oxidizing agent contained in the second agent and swells the hair to improve the permeability of the dye to the hair. The oxidizing agent decomposes the melanin pigment in the hair and forms an oxidation dye polymer inside the hair. After the alkaline agent is removed, the cuticle of the hair closes and the oxidation dye polymer is encapsulated inside the hair.

[0003] Oxidative hair dyes can dye hair in various color tones by using various dyes. As such an oxidation dye, 4,5-diaminopyrazole derivatives are known, and an oxidative hair dye containing a 4,5-diaminopyrazole derivative can exhibit a vivid red color. For example, Patent Document 1 describes a gel-like oxidative hair dye composition containing 4,5-diamino-1-hydroxyethylpyrazole and its salts, an anionic surfactant, and a specific nonionic surfactant.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] Oxidative hair dyes containing 4,5-diaminopyrazole derivatives have the problem of poor color transfer (high color transfer). However, in oxidative hair dyes containing 4,5-diaminopyrazole derivatives, reducing the amount of 4,5-diaminopyrazole derivatives to suppress color transfer results in hair dyeing. force が It will be inferior.

[0006] The object of the present invention is to provide an oxidative hair dye containing a 4,5-diaminopyrazole derivative while maintaining dyeing power. ,shift The objective is to provide an oxidative hair dye that can suppress dyeing properties. [Means for solving the problem]

[0007] As a result of diligent research into the above problems, the inventors have found that in an oxidative hair dye containing a 4,5-diaminopyrazole derivative, by including a large amount of coupler, which is a type of oxidative dye, the dyeing power can be maintained while ,shift We completed the present invention by discovering that it is possible to suppress dyeing properties.

[0008] In other words, the present invention relates to an oxidative hair dye containing (A) a coupler and (B) a compound shown in general formula (1), characterized in that the content of (A) the coupler is 0.3% by mass or more, and the mass ratio (B / A) of the content of (A) the coupler to the content of (B) the compound shown in general formula (1) is 0.5 or less. [ka] (Here, R represents a linear or branched alkyl group having 1 to 6 carbon atoms, a linear or branched mono- or polyhydroxyalkyl group having 2 to 6 carbon atoms, or a linear or branched mono- or polyaminoalkyl group.) According to this feature, the oxidative hair dye of the present invention maintains its dyeing power while ,shift It can suppress dyeing properties.

[0009] Furthermore, the present invention is an oxidative hair dye characterized in that the compound shown in (B) general formula (1) above is 1-hydroxyethyl-4,5-diaminopyrazole and / or its sulfate. According to this feature, the oxidative hair dye of the present invention can further improve its hair dyeing power.

[0010] Furthermore, the present invention is an oxidative hair dye characterized in that the content of the compound shown in (B) general formula (1) above is 0.3% by mass or less. According to this feature, the oxidative hair dye of the present invention can further suppress color transfer.

[0011] Furthermore, the present invention is an oxidative hair dye characterized in that the mass ratio (C / A) of the content of (A) coupler to the content of (C) dye intermediate contained in the oxidative hair dye is 0.4 or less. According to this feature, the oxidative hair dye of the present invention can have good decolorization performance.

[0012] Furthermore, the oxidative hair dye of the present invention is characterized in that the (A) coupler contains (A-1)2,4-diaminophenoxyethanol and / or a salt thereof, and the content of (A-1)2,4-diaminophenoxyethanol and / or a salt thereof in the (A) coupler is 30% by mass or more. According to this feature, the oxidative hair dye of the present invention can further improve its hair dyeing power. [Effects of the Invention]

[0013] In an oxidative hair dye containing a 4,5-diaminopyrazole derivative, while maintaining the dyeing power ,shift This invention provides an oxidative hair dye that can suppress dyeing properties. [Modes for carrying out the invention]

[0014] The best mode for carrying out the present invention will be described. [Oxidative hair dye] The present invention relates to an oxidative hair dye containing (A) a coupler and (B) a compound shown in general formula (1), characterized in that the content of (A) the coupler is 0.3% by mass or more, and the mass ratio (B / A) of the content of (A) the coupler to the content of (B) the compound shown in general formula (1) is 0.5 or less. [ka] (Here, R represents a linear or branched alkyl group having 1 to 6 carbon atoms, a linear or branched mono- or polyhydroxyalkyl group having 2 to 6 carbon atoms, or a linear or branched mono- or polyaminoalkyl group.)

[0015] Hair dyes are classified into temporary, semi-permanent, and permanent hair dyes based on the persistence of their coloring effect, i.e., color fastness. The oxidative hair dye of the present invention is a hair dye containing an oxidative dye and is classified as a permanent hair dye. Oxidative hair dyes distribute the oxidizing agent and the oxidative dye separately, allowing the oxidative dye to develop color inside the hair. Typically, it comprises a first agent containing the oxidative dye and a second agent containing the oxidizing agent. The oxidative hair dye can be used on hair by mixing the first and second agents, or by using the first and second agents separately. Here, "using a mixture on hair" means applying an oxidative hair dye consisting of multiple agents to the hair in a single application operation. This includes not only the operation of mixing the first and second agents immediately before application using a mixing container, but also the operation of taking the first and second agents on a comb and mixing them on the hair using the comb.

[0016] As described above, the oxidative hair dye is typically a two-component type consisting of a first agent and a second agent, but it is not limited thereto. A part of each component contained in the first agent and the second agent may be configured as a separate agent, and it may be a multi-component type consisting of three or more agents. For example, the first agent of the two-component type may be divided into two agents, one containing a coupler and an alkaline agent which is an optional component, and the other having a different composition, and configured as a three-component oxidative hair dye. In this case, the emulsion stability is further improved. Further, as a means for applying the oxidative hair dye to the hair, it may be applied to the hair using an applicator such as a comb, brush, bristle, or applicator. Also, the oxidative hair dye may be applied to the hair with a gloved hand.

[0017] The form of each agent forming the oxidative hair dye of the present invention may be any form, and examples of the dosage form at 25°C include liquid forms such as aqueous solutions and emulsions, gel forms, foam forms, cream forms, solid forms, etc. It can also be in the form of an aerosol, non-aerosol, etc. In the case of a non-aerosol, it can further take various forms such as a squeeze-former type and a pump-former type. In the case of an aerosol, known jetting agents and foaming agents can be applied. In the case of a solid dosage form, a dispersant may be blended.

[0018] Further, the oxidative hair dye after mixing of each agent is not particularly limited as long as it is a dosage form applicable to the hair. Specific examples of the dosage form at 25°C include liquid forms such as aqueous solutions and emulsions, gel forms, foam forms, cream forms, etc. From the viewpoint of improving the ease of picking up with a brush, the elongation and adhesion to the hair, and excellent coating operability, it is preferably in the form of a cream or paste. Some agents may contain powders or solids. Also, it may be in the form of foam or mist during use. In the case of foam, an aerosol former container, a non-aerosol former container, a shaking container, etc. may be used, or it may be formed by self-foaming by mixing the oxidative hair dye in a mixing container and a mixing instrument, or the oxidative hair dye may be filled in a shaking container and shaken to form foam. In the case of mist, a sprayer may be used.

[0019] A configuration may be adopted in which the (A) coupler and the oxidizing agent are stored in the same agent by using a powdered (A) coupler and a powdered oxidizing agent. When a powdered agent is used, it is dissolved in the solvent at the time of use.

[0020] When the oxidative hair dye of the present invention is a two-part oxidative hair dye, the mixing ratio of the first agent and the second agent is set appropriately considering the concentration of each component in the mixture, the mixability, the application method, etc., but is preferably 0.1 to 10:1, and more preferably 0.5 to 2:1.

[0021] Even if the oxidative hair dye is a composition containing three or more components or a powder, it is still included in the present invention as long as it achieves the effects of the present invention.

[0022] Next, each component of the oxidative hair dye of the present invention will be described in detail. Unless otherwise specified, the content of each component refers to the content in the oxidative hair dye when each agent is mixed.

[0023] <(A) Coupler> A coupler is a type of oxidation dye. Oxidation dyes are classified into (A) couplers and (C) dye intermediates.

[0024] Examples of couplers include m-diamines, aminophenols, or diphenols, specifically resorcinol, 5-amino-o-cresol, m-aminophenol, α-naphthol (1-naphthol), 5-(2-hydroxyethylamino)-2-methylphenol, m-phenylenediamine, 2,4-diaminophenoxyethanol, toluene-3,4-diamine, 2,6-diaminopyridine, diphenylamine, N,N-diethyl-m-aminophenol, phenylmethylpyrazolone, 1,5-dihydroxynaphthalene, catechol, pyrogallol, phloroglucin, gallic acid, hydroquinone, 3,3'-iminodiphenyl, tannic acid, and their salts. Specific examples of salts include hydrochloride salts and sulfate salts.

[0025] (A) The coupler is preferably 2,4-diaminophenoxyethanol, 5-amino-o-cresol, 2,6-diaminopyridine, 5-(2-hydroxyethylamino)-2-methylphenol and their salts, and is particularly preferably (A-1) 2,4-diaminophenoxyethanol and / or its salts from the viewpoint of hair dyeing power.

[0026] The coupler can be selected and used in one or more types depending on the desired hair color. The content of (A) coupler is 0.3% by mass or more as the total content. The lower limit is more preferably 0.5% by mass or more, and even more preferably 1% by mass or more. When the content of (A) coupler is 0.3% by mass or more, the hair dyeing power can be improved.

[0027] The upper limit of the content of (A) coupler is set as appropriate, but the total content of (A) coupler is preferably 10% by mass or less, more preferably 7% by mass or less, even more preferably 5% by mass or less, and most preferably 3.5% by mass or less. When the content of (A) coupler is 10% by mass or less, the destaining performance can be further improved, and when a solubilizer is used, the solubility to the solubilizer can be improved. If (A) coupler is a salt, the content of (A) coupler shall be the value in its desalting form.

[0028] <(A-1) 2,4-diaminophenoxyethanol or / and its salts> (A-1) 2,4-diaminophenoxyethanol and / or its salts are a type of coupler that can develop color due to oxidative polymerization by an oxidizing agent.

[0029] When (A-1)2,4-diaminophenoxyethanol and / or its salts are included as a coupler, it is preferable that (A-1)2,4-diaminophenoxyethanol and / or its salts are included as the main component in the entire (A) coupler, from the viewpoint of hair dyeing power based on (A-1)2,4-diaminophenoxyethanol and / or its salts. The content of (A-1)2,4-diaminophenoxyethanol and / or its salts in the (A) coupler is not particularly limited, but is preferably 30% by mass or more, more preferably 40% by mass or more, even more preferably 50% by mass or more, and even more preferably 60% by mass or more.

[0030] The content of (A-1)2,4-diaminophenoxyethanol and / or its salts is not particularly limited, but for example, it is 0.1% to 5% by mass. The lower limit of its content is preferably 0.15% by mass or more, more preferably 0.2% by mass or more, and even more preferably 0.25% by mass or more. The upper limit of its content is preferably 4% by mass or less, more preferably 3% by mass or less, and even more preferably 2% by mass or less. When the content of (A-1)2,4-diaminophenoxyethanol and / or its salts is 0.1% by mass or more, the hair dyeing power can be further enhanced. Note that if (A-1)2,4-diaminophenoxyethanol and / or its salts are salts, the content of (A-1)2,4-diaminophenoxyethanol and / or its salts shall be the value in its desalted form.

[0031] <Dye intermediate> (C) The dye intermediate is a dye classified as an oxidation dye. The oxidation hair dye of the present invention contains a heterocyclic compound having a specific structure as the (C) dye intermediate.

[0032] <4,5-diaminopyrazole derivatives> The oxidative hair dye of the present invention contains the compound shown in (B) General Formula (1) below. [ka] (Here, R represents a linear or branched alkyl group having 1 to 6 carbon atoms, a linear or branched mono- or polyhydroxyalkyl group having 2 to 6 carbon atoms, or a linear or branched mono- or polyaminoalkyl group.)

[0033] As the compound shown in (B) general formula (1) above, 1-hydroxyethyl-4,5-diaminopyrazole and / or its sulfate shown in formula (2) below is preferred. [ka]

[0034] The dye intermediate consisting of the compound of general formula (1) (B) above exhibits higher saturation compared to other dye intermediates.

[0035] The content of the compound shown in (B) General Formula (1) in the oxidative hair dye of the present invention is not particularly limited, but for example, it is 0.006 to 0.6% by mass. As a lower limit, from the viewpoint of dyeing power and saturation, it is preferably 0.012% by mass or more, more preferably 0.018% by mass or more, and even more preferably 0.03% by mass or more. As an upper limit, from the viewpoint of color transfer and decolorization performance, it is preferably 0.42% by mass or less, more preferably 0.3% by mass or less, and even more preferably 0.18% by mass or less. By setting it to 0.6% by mass or less, color transfer can be suppressed, and by setting it to 0.006% by mass or more, sufficient dyeing power and saturation can be obtained. When the compound shown in (B) General Formula (1) is a salt, the content of the compound shown in (B) General Formula (1) is the value in its desalted form.

[0036] The mass ratio (B / A) of the content of the compound shown in (B) general formula (1) to the content of the coupler shown in (A) is 0.5 or less. The lower limit is preferably 0.0025 or more, more preferably 0.005 or more, and even more preferably 0.01 or more. The upper limit is preferably 0.4 or less, and more preferably 0.3 or less. When (B / A) is 0.5 or less, color transfer can be sufficiently suppressed and good destaining performance can be achieved. When (B / A) is 0.0025 or more, sufficient saturation can be achieved. When the coupler shown in (A) and the compound shown in (B) general formula (1) are salts, the content used in calculating the mass ratio is the value of the desalted form of the coupler shown in (A) and the compound shown in (B) general formula (1).

[0037] <Other dye intermediates> The oxidative hair dye of the present invention may contain dye intermediates other than those shown in the compound of general formula (1) above (B). The dye intermediates other than those shown in the compound of general formula (1) above (B) are dye precursors that are mainly o- or p-phenylenediamines or aminophenols, and are usually colorless or weakly colored compounds. Specifically, examples include p-phenylenediamine, o-phenylenediamine, N-phenyl-p-phenylenediamine, 4,4'-diaminodiphenylamine, p-aminophenol, o-aminophenol, p-methylaminophenol, 2-hydroxyethyl-p-phenylenediamine, o-chlor-p-phenylenediamine, 4-amino-m-cresol, 2-amino-4-hydroxyethylaminoanisole, 2,4-diaminophenol, p-toluylenediamine (toluene-2,5-diamine), 4,4'-diaminodiphenylamine, N,N-bis(2-hydroxyethyl)-p-phenylenediamine and their salts. Specific examples of salts include hydrochloride salts and sulfate salts. One dye intermediate may be used alone, or two or more dye intermediates may be used in combination. The oxidative hair dye of the present invention may appropriately contain, as dyes other than the (A) coupler, (B) compound shown in general formula (1), and the other specific examples of dye intermediates, oxidative dyes listed in the "Standards for Ingredients of Quasi-Drugs" (published June 2006, Yakuji Nippo Co., Ltd.).

[0038] The mass ratio (C / A) of the total (C) dye intermediate content, including the compound shown in (B) general formula (1), to the content of the (A) coupler is not particularly limited, but is preferably 0.4 or less, more preferably 0.2 or less, even more preferably 0.15 or less, and even more preferably 0.1 or less. When such a mass ratio (C / A) is 0.4 or less, the destaining performance can be improved. When the (A) coupler, the compound shown in (B) general formula (1), and the (C) dye intermediate are salts, the content values ​​used in calculating the mass ratio are the values ​​of their desalted forms for (A), (B), and (C).

[0039] The upper limit of the content of the (C) dye intermediate is appropriately set within the range of the mass ratio of the content (C / A), but is preferably 1% by mass or less, more preferably 0.5% by mass or less, and even more preferably 0.2% by mass or less. When the content of the (C) dye intermediate is 1% by mass or less, the color transfer and decolorization performance can be further improved, and when a solubilizer is used, the solubility to the solubilizer can be improved. In the case of the (C) dye intermediate being a salt, the content of the (C) dye intermediate shall be the value in its desalted form.

[0040] Polymers of dye intermediates, or polymers of dye intermediates and couplers, have the characteristic of being difficult to decompose with alkaline agents or oxidizing agents, which has resulted in the problem that lighter hair colors cannot be dyed in subsequent treatments. The oxidative hair dye of the present invention contains the compound shown in (B) general formula (1) and all (C) dye intermediates including the compound shown in (B) general formula (1) in a predetermined ratio or less with respect to the (A) coupler, thereby forming polymers that are easily decomposed by alkaline agents, resulting in excellent decolorization performance and less impact on subsequent hair coloring. As a result, it is possible to enjoy various hair colors without having to consider the next hair coloring treatment.

[0041] Because the oxidative hair dye of the present invention contains only trace amounts of dye intermediates, it may be usable even for individuals who are allergic to specific dye intermediates.

[0042] <Iodine compounds> The oxidative hair dye of the present invention may contain an iodine compound. The iodine compound improves the hair dyeing power by decomposing hydrogen peroxide with the iodine constituting the iodine compound, thereby promoting the polymerization of the oxidative dye. The iodine compound is usually contained in the first agent of the oxidative hair dye. Examples of iodine compounds include iodine(I), iodides accompanied by counterions that are released in the solubilizer, and compounds that release iodine upon use. Specific examples of iodides include alkali metal salts of iodides such as potassium iodide, sodium iodide, lithium iodide, and ammonium iodide, as well as hydrogen iodide, cesium iodide, and silver iodide. In addition, natural materials containing iodine, such as extracts containing iodides such as garlic iodide extract, may also be used. One type of iodine compound may be used alone, or two or more types of iodine compounds may be used in combination.

[0043] The content of iodine compounds in the oxidative hair dye is not particularly limited, but for example, it is 0 to 3% by mass. The lower limit is set as appropriate, but from the viewpoint of dyeing power, it is preferably 0.001% by mass or more, more preferably 0.005% by mass or more, even more preferably 0.01% by mass or more, even more preferably 0.015% by mass or more, and particularly preferably 0.02% by mass or more. The upper limit is set as appropriate, but from the viewpoint of improving decolorization performance, it is preferably 2% by mass or less, more preferably 1% by mass or less, even more preferably 0.75% by mass or less, and even more preferably 0.5% by mass or less.

[0044] <Oxidizing agent> The oxidizing agent is a component contained in the second agent and can be any substance that has oxidizing power. The oxidizing agent has the effect of oxidizing the oxidative dye to produce color, or the effect of breaking down melanin inside the hair. Specifically, examples include hydrogen peroxide, urea peroxide, melamine peroxide, sodium percarbonate, potassium percarbonate, sodium perborate, potassium perborate, ammonium persulfate, potassium persulfate, sodium persulfate, sodium peroxide, potassium peroxide, magnesium peroxide, barium peroxide, calcium peroxide, strontium peroxide, hydrogen peroxide adducts of sulfates, hydrogen peroxide adducts of phosphates, hydrogen peroxide adducts of pyrophosphates, persulfates such as potassium persulfate and sodium persulfate, peracetic acid and its salts, performic acid and its salts, permanganate, bromate salts, etc. Among these, hydrogen peroxide is preferred. In addition, persulfates such as ammonium persulfate, potassium persulfate, and sodium persulfate may be contained as oxidizing aids.

[0045] The content of the oxidizing agent in the oxidative hair dye of the present invention is not particularly limited, but is, for example, 0.1 to 15% by mass, more preferably 1 to 9% by mass. When hydrogen peroxide is included as the oxidizing agent, it is preferable to include ethylene glycol phenyl ether (phenoxyethanol), hydroxyethane diphosphonic acid, phosphoric acid, citric acid, or a salt thereof as a stabilizer to improve its stability.

[0046] <Alkaline agent> Alkaline agents have the effect of swelling hair and promoting the penetration of dyes and oxidizing agents. Examples of alkaline agents include ammonia, alkanolamines, silicates, carbonates, bicarbonates, carbamates, metasilicates, phosphates, sulfates, basic amino acids, chlorides, organic amines, and hydroxides. Specifically, examples of alkanolamines include monoethanolamine, diethanolamine, triethanolamine, monoisopropanolamine, aminomethylpropanol, and isopropylamine; examples of silicates include sodium silicate and potassium silicate; examples of carbonates include sodium carbonate, ammonium carbonate, magnesium carbonate, and guanidine carbonate; examples of bicarbonates include sodium bicarbonate and ammonium bicarbonate; examples of carbamates include ammonium carbamate; and examples of metasilicates include sodium metasilicate and potassium metasilicate. Examples of phosphates include monoammonium phosphate, disodium ammonium phosphate, disodium monohydrogen phosphate, trisodium phosphate, diammonium dihydrogen phosphate, and diammonium hydrogen phosphate; examples of sulfates include ammonium sulfate; examples of basic amino acids include arginine, lysine, and their salts; examples of chlorides include ammonium chloride; examples of organic amines include 2-amino-2-methyl-1-propanol (AMP) and 2-amino-2-methyl-1,3-propanediol; and examples of hydroxides include calcium hydroxide and magnesium hydroxide. Among these, ammonia, alkanolamines, ammonium carbonate, and ammonium bicarbonate are preferred. The alkaline agent is usually included in the first agent.

[0047] The content of the alkaline agent in the oxidative hair dye is not particularly limited, but the lower limit is preferably 0.5% by mass or more, more preferably 0.75% by mass or more, and even more preferably 1% by mass or more. The upper limit is preferably 10% by mass or less, more preferably 7% by mass or less, and even more preferably 5% by mass or less. The content of the alkaline agent in the first agent is not particularly limited, but the lower limit is preferably 1% by mass or more, more preferably 1.5% by mass or more, and even more preferably 2% by mass or more. The upper limit is preferably 20% by mass or less, more preferably 14% by mass or less, and even more preferably 10% by mass or less.

[0048] [Other ingredients] In addition to the above-mentioned components, the oxidative hair dye of the present invention may also contain the following components as needed. Other ingredients include, for example, direct dyes, oily components, surfactants, polyhydric alcohols, antioxidants such as ascorbic acid and sodium sulfite anhydrous, preservatives such as phenoxyethanol and sodium benzoate, sugars such as sorbitol and maltose, water-soluble polymers such as hydroxyethylcellulose and carboxyvinyl polymer, cationized water-soluble polymers such as polydimethylmethylene piperidinium chloride solution (polydimethylmethylene pyrrolidinium chloride solution) and diallyldimethylammonium chloride / hydroxyethylcellulose, and polyethylene glycosides. Examples of ingredients include polyhydric alcohols such as dipropylene glycol, chelating agents such as ethylenediamine hydroxyethyl triacetate trisodium dihydrate and hydroxyethane diphosphonate tetrasodium solution, inorganic salts such as sodium chloride, ammonium sulfate, ammonium nitrate, ammonium acetate, citric acid, tartaric acid, lactic acid, malic acid, succinic acid, fumaric acid, maleic acid, pyrophosphate, gluconic acid, glucuronic acid, pH adjusters, hair growth ingredients, plant extracts, herbal extracts, amino acids / peptides, urea, vitamins, fragrances, UV absorbers, solubilizers, and stabilizers.

[0049] <Direct dye> Direct dyes are colored compounds that adhere to or penetrate hair to color it. Examples include acid dyes, basic dyes, natural dyes, nitro dyes, HC dyes, and disperse dyes. These direct dyes may be used individually or in combination.

[0050] Examples of the aforementioned acid dyes include Red No. 2, Red No. 3, Red No. 102, Red No. 104 (1), Red No. 105 (1), Red No. 106, Red No. 227, Red No. 230 (1), Yellow No. 4, Yellow No. 5, Yellow No. 202 (1), Yellow No. 202 (2), Yellow No. 203, Orange No. 205, Orange No. 207, Orange No. 402, Green No. 3, Green No. 204, Green No. 401, Purple No. 401, Blue No. 1, Blue No. 2, Blue No. 202, Brown No. 201, Black No. 401, and the like.

[0051] The basic dyes include Basic Blue 3, Basic Blue 6, Basic Blue 7, Basic Blue 9, Basic Blue 26, Basic Blue 41, Basic Blue 47, Basic Blue 99, Basic Brown 4, Basic Brown 16, Basic Brown 17, Basic Green 1, Basic Green 4, Basic Orange 1, Basic Orange. 2, Basic Orange 31, Basic Red 1, Basic Red 2, Basic Red 22, Basic Red 46, Basic Red 51, Basic Red 76, Basic Red 118, Basic Violet 1, Basic Violet 3, Basic Violet 4, Basic Violet 10, Basic Violet11:1, Basic Examples include Violet 14, Basic Violet 16, Basic Yellow 11, Basic Yellow 28, Basic Yellow 57, and Basic Yellow 87.

[0052] Examples of the aforementioned natural dyes include gardenia pigment, turmeric pigment, annatto pigment, copper chlorophyllin sodium, paprika pigment, lac pigment, and henna.

[0053] Examples of the nitro dyes include 4-nitro-o-phenylenediamine, 2-nitro-p-phenylenediamine, 2-amino-4-nitrophenol, 2-amino-5-nitrophenol, picramic acid, picric acid, and salts thereof.

[0054] The HC dyes include HC Blue No.2, HC Blue No.5, HC Blue No.6, HC Blue No.9, HC Blue No.10, HC Blue No.11, HC Blue No.12, HC Blue No.13, HC Orange No.1, HC Orange No.2, HC Orange No.3, HC Red No.1, HC Red No.3, HC Red No.7, HC Red No.10, HC Red No.11, HC Red No.13, HC. Examples include Red No.14, HC Violet No.1, HC Violet No.2, HC Yellow No.2, HC Yellow No.4, HC Yellow No.5, HC Yellow No.6, HC Yellow No.9, HC Yellow No.10, HC Yellow No.11, HC Yellow No.12, HC Yellow No.13, HC Yellow No.14, and HC Yellow No.15.

[0055] Examples of the aforementioned disperse dyes include Disperse Black 9, Disperse Blue 1, Disperse Blue 3, Disperse Blue 7, Disperse Brown 4, Disperse Orange 3, Disperse Red 11, Disperse Red 15, Disperse Red 17, Disperse Violet 1, Disperse Violet 4, Disperse Violet 15, etc.

[0056] The direct dye content in the oxidative hair dye is not particularly limited, but is preferably 0.001 to 10% by mass. More preferably, the lower limit is 0.01% by mass or more, and even more preferably 0.05% by mass or more. More preferably, the upper limit is 5% by mass or less, and even more preferably 3% by mass or less.

[0057] <Oily components> Examples of oily components include higher alcohols, fats and oils, waxes, hydrocarbons, higher fatty acids, esters, silicone oils, and fluorinated oils. One or more of these oily components can be selected and used. Including oily components can improve hair dyeing performance.

[0058] Examples of higher alcohols include cetyl alcohol (cetanol), stearyl alcohol, cetostearyl alcohol, oleyl alcohol, linoleyl alcohol, linolenyl alcohol, arachidyl alcohol, behenyl alcohol, lauryl alcohol, myristyl alcohol, 2-hexyldecanol, isostearyl alcohol, 2-octyldodecanol, decyltetradecanol, phytosterol, phytostanol, cholesterol, cholestanol, lanosterol, and ergosterol. Among these, cetyl alcohol (cetanol), stearyl alcohol, cetostearyl alcohol, arachidyl alcohol, and behenyl alcohol are preferred from the viewpoint of emulsification stability and ease of handling.

[0059] Fats and oils are triglycerides, that is, triesters of fatty acids and glycerol. Examples include olive oil, rosehip oil, camellia oil, shea butter, macadamia nut oil, almond oil, tea seed oil, sasanqua oil, safflower oil, sunflower oil, soybean oil, cottonseed oil, sesame oil, beef tallow, cocoa butter, corn oil, peanut oil, rapeseed oil, rice bran oil, rice germ oil, wheat germ oil, Job's tears oil, grape seed oil, avocado oil, carrot oil, castor oil, linseed oil, coconut oil, mink oil, and egg yolk oil.

[0060] Waxes are esters of higher fatty acids and higher alcohols. Examples include beeswax, candelilla wax, carnauba wax, jojoba oil, lanolin, whale wax, rice bran wax, sugarcane wax, palm wax, montan wax, cotton wax, bayberry wax, privet wax, kapok wax, and shellac wax.

[0061] Hydrocarbons are compounds composed of carbon and hydrogen. Examples include liquid paraffin, paraffin, microcrystalline wax, petrolatum, isoparaffins, ozokerite, ceresin, polyethylene, α-olefin oligomers, polybutene, synthetic squalane, squalene, hydrogenated squalane, limonene, and turpentine oil. Among these, petrolatum and liquid paraffin are preferred from the viewpoint of emulsification stability and ease of handling.

[0062] Examples of higher fatty acids include lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, isostearic acid, hydroxystearic acid, 12-hydroxystearic acid, oleic acid, undecylenic acid, linoleic acid, ricinoleic acid, and lanolinic acid.

[0063] Esters are compounds obtained by the dehydration reaction of fatty acids and alcohols. Examples include diisopropyl adipate, 2-hexyldecyl adipate, isopropyl myristate, myristyl myristate, cetyl octanoate, cetyl isooctanoate, isononyl isononanoate, diisopropyl sebacate, isopropyl palmitate, 2-ethylhexyl palmitate, cetyl ethylhexanoate (2-ethylhexanoate cetyl), butyl stearate, isocetyl isostearate, hexyl laurate, decyl oleate, fatty acids (C10-30) (cholesteryl / lanosteryl), lauryl lactate, octyldodecyl lactate, lanolin acetate, dipentaerythritol fatty acid esters, N-alkyl glycol monoisostearate, and lanolin derivatives.

[0064] Silicone oils are synthetic polymers in which silicon atoms with organic groups and oxygen atoms are alternately linked by chemical bonds. Examples include dimethylpolysiloxane (INCI name: dimethicone), dimethylpolysiloxane with hydroxyl-terminated groups (INCI name: dimethiconol), methylphenylpolysiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, polyether-modified silicones, highly polymerized silicones with an average degree of polymerization of 650 to 10000, amino-modified silicones, betaine-modified silicones, alkyl-modified silicones, alkoxy-modified silicones, mercapto-modified silicones, carboxy-modified silicones, and fluorine-modified silicones.

[0065] Examples of amino-modified silicones include aminopropylmethylsiloxane-dimethylsiloxane copolymer (INCI name: aminopropyldimethicone), aminoethylaminopropylsiloxane-dimethylsiloxane copolymer (INCI name: amodimethicone), and aminoethylaminopropylmethylsiloxane-dimethylsiloxane copolymer (INCI name: trimethylsilylamodimethicone).

[0066] The oily component content in the oxidative hair dye is not particularly limited, but is preferably 0.1 to 20% by mass. More preferably, the lower limit is 0.2% by mass or more, even more preferably 0.5% by mass or more, even more preferably 1% by mass or more, and particularly preferably 2% by mass or more. More preferably, the upper limit is 17% by mass or less, even more preferably 15% by mass or less, even more preferably 12% by mass or less, and particularly preferably 10% by mass or less.

[0067] <Surfactants> Examples of surfactants include nonionic surfactants, cationic surfactants, anionic surfactants, and amphoteric surfactants. In the following descriptions, POE refers to a polyoxyethylene chain, POP refers to a polyoxypropylene chain, and the number in parentheses following them indicates the number of moles added. The number in parentheses following the alkyl group indicates the number of carbon atoms in the fatty acid chain.

[0068] Examples of nonionic surfactants include POE alkyl ethers, POE alkylphenyl ethers, POE·POP alkyl ethers, POE sorbitan fatty acid esters, POE mono fatty acid esters, POE glycerin fatty acid esters, polyglycerin fatty acid esters, monoglycerin fatty acid esters, sorbitan fatty acid esters, sucrose fatty acid esters, and alkyl polyglucosides. Specific examples of POE alkyl ethers include POE lauryl ether, POE cetyl ether, POE stearyl ether, POE behenyl ether, POE lanolin, and POE phytosterol. The number of repeating units for POE and POP can range from 2 to 100, and any combination that exhibits surfactant activity can be used.

[0069] The content of nonionic surfactant in the oxidative hair dye is not particularly limited, but is preferably 0.001 to 30% by mass. More preferably, the lower limit is 0.01% by mass or more, even more preferably 0.05% by mass or more, even more preferably 0.1% by mass or more, and particularly preferably 0.2% by mass or more. More preferably, the upper limit is 20% by mass or less, even more preferably 10% by mass or less, even more preferably 7% by mass or less, and particularly preferably 5% by mass or less.

[0070] Examples of cationic surfactants include alkyl quaternary ammonium salts such as monoalkyl quaternary ammonium salts, dialkyl quaternary ammonium salts, trialkyl quaternary ammonium salts, benzalkonium quaternary ammonium salts, and monoalkyl ether quaternary ammonium salts; amine salts such as alkylamine salts, fatty acid amidoamine salts, ester-containing tertiary amine salts, and Arcover tertiary amine salts; cyclic quaternary ammonium salts such as alkylpyridinium salts and alkylisoquinolium salts; and benzethonium chloride.

[0071] Preferably, the salts are alkyl quaternary ammonium salts, more preferably monoalkyl quaternary ammonium salts and dialkyl quaternary ammonium salts, and particularly preferably monoalkyl quaternary ammonium salts.

[0072] From the viewpoint of formulation stability, examples of monoalkyl quaternary ammonium salts include lauryltrimethylammonium chloride, lauryltrimethylammonium bromide, alkyl(16,18)trimethylammonium chloride, cetyltrimethylammonium chloride, cetyltrimethylammonium bromide, cetyltrimethylammonium saccharin, stearyltrimethylammonium chloride, stearyltrimethylammonium bromide, behenyltrimethylammonium chloride, stearyltrimethylammonium saccharin, alkyl(28)trimethylammonium chloride, diPOE(2)oleylmethylammonium chloride, diPOEstearylmethylammonium chloride, POE(1)POP(25)diethylmethylammonium chloride, POPmethyldiethylammonium chloride, methacryloyloxyethyltrimethylammonium chloride, and behenyltrimethylammonium methyl sulfate. Particularly preferred are stearyltrimethylammonium chloride, alkyl(16,18)trimethylammonium chloride, cetyltrimethylammonium chloride, and behenyltrimethylammonium chloride.

[0073] Examples of dialkyl-type quaternary ammonium salts include dialkyl(12-15)dimethylammonium chloride, dialkyl(12-18)dimethylammonium chloride, dialkyl(14-18)dimethylammonium chloride, dicocoyldimethylammonium chloride, dicetyldimethylammonium chloride, distearyldimethylammonium chloride, and isostearyllauryldimethylammonium chloride.

[0074] The content of cationic surfactant in the oxidative hair dye is not particularly limited, but is preferably 0.01 to 10% by mass. More preferably, the lower limit is 0.05% by mass or more, even more preferably 0.1% by mass or more, and even more preferably 0.2% by mass or more. More preferably, the upper limit is 7.5% by mass or less, even more preferably 5% by mass or less, and even more preferably 1.5% by mass or less.

[0075] Examples of anionic surfactants include alkyl ether sulfates, POE alkyl ether sulfates, alkyl sulfates, alkenyl ether sulfates, alkenyl sulfates, olefin sulfonates, alkanesulfonates, saturated or unsaturated fatty acid salts, alkyl or alkenyl ether carboxylates, α-sulfone fatty acid salts, N-acyl amino acid type surfactants, phosphate mono or diester type surfactants, and sulfosuccinate esters. The counterions of the anionic groups of these surfactants may be, for example, sodium ions, potassium ions, and triethanolamine.

[0076] More specifically, examples include sodium lauryl sulfate, sodium myristyl sulfate, potassium lauryl sulfate, ammonium lauryl sulfate, triethanolamine lauryl sulfate, sodium cetyl sulfate, sodium stearyl sulfate, sodium POE lauryl ether sulfate, triethanolamine POE lauryl ether sulfate, ammonium POE lauryl ether sulfate, sodium POE stearyl ether sulfate, sodium stearoyl methyl taurate, triethanolamine dodecylbenzenesulfonate, sodium tetradecenesulfonate, sodium lauryl phosphate, POE lauryl etheric acid and its salts, N-lauroyl glutamates (such as sodium lauroyl glutamate), N-lauroyl methyl-β-alanine salt, N-acylglycine salt, N-acyl glutamate, and higher fatty acids such as lauric acid, myristic acid, and salts of these higher fatty acids. One or more of these can be used.

[0077] The content of anionic surfactant in an oxidative hair dye is not particularly limited, but is preferably 0.01 to 5% by mass. More preferably, the lower limit is 0.02% by mass or more, even more preferably 0.05% by mass or more, even more preferably 0.07% by mass or more, and particularly preferably 0.1% by mass or more. More preferably, the upper limit is 4% by mass or less, even more preferably 3% by mass or less, even more preferably 2% by mass or less, and particularly preferably 1% by mass or less.

[0078] Examples of amphoteric surfactants include amino acid-type amphoteric surfactants and betaine-type amphoteric surfactants. Specific examples of amino acid-type amphoteric surfactants include, for example, N-lauroyl-N'-carboxymethyl-N'-hydroxyethylethylenediamine sodium (lauroamphoacetate sodium), 2-alkyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine, undecylhydroxyethylimidazolinium betaine sodium, alkyldiaminoethylglycine hydrochloride, N-coconut oil fatty acid acyl-N'-carboxyethyl-N'-hydroxyethylethylenediamine sodium, and N-coconut oil fatty acid acyl-N'-carboxyethoxyethyl-N' Examples include glycine-type amphoteric surfactants such as disodium carboxyethylethylenediamine, disodium N-coconut oil fatty acid acyl-N'-carboxymethoxyethyl-N'-carboxymethylethylenediamine, sodium lauryldiaminoethylglycine, and sodium palm oil fatty acid acyl-N-carboxyethyl-N-hydroxyethylethylenediamine, as well as aminopropionic acid-type amphoteric surfactants such as sodium laurylaminopropionate, sodium laurylaminodipropionate, and triethanolamine laurylaminopropionate. Specific examples of betaine-type amphoteric surfactants include, for example, aminoacetic acid betaine-type amphoteric surfactants such as coconut oil alkyl betaine, lauryldimethylaminoacetic acid betaine, myristyldimethylaminoacetic acid betaine, stearyldimethylaminoacetic acid betaine, stearyldimethylbetaine sodium, coconut oil fatty acid amidopropyl betaine, palm oil fatty acid amidopropyl betaine, lauric acid amidopropyl betaine, ricinoleic acid amidopropyl betaine, and stearyl dihydroxyethyl betaine, as well as sulfobetaine-type amphoteric surfactants such as lauryl hydroxysulfobetaine.

[0079] The content of amphoteric surfactant in the oxidative hair dye is not particularly limited, but is preferably 0.001 to 5% by mass. More preferably, the lower limit is 0.005% by mass or more, and even more preferably 0.01% by mass or more. More preferably, the upper limit is 3% by mass or less, and even more preferably 2.5% by mass or less.

[0080] The total content of all surfactants in the oxidative hair dye is not particularly limited, but is preferably 0.01 to 50% by mass. The lower limit is more preferably 0.05% by mass or more, and even more preferably 0.1% by mass or more. The upper limit is more preferably 40% by mass or less, and even more preferably 30% by mass or less.

[0081] <Polyhydric alcohols> The oxidative hair dye of the present invention may further contain a polyhydric alcohol. (F) When a polyhydric alcohol is included, the formulation stability can be improved. (F) Examples of polyhydric alcohols include glycol and glycerin. Examples of glycols include ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, high polymerization polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, isoprene glycol, and 1,3-butylene glycol. Examples of glycerin include glycerin, diglycerin, and polyglycerin. One polyhydric alcohol may be used alone, or two or more polyhydric alcohols may be used in combination. From the viewpoint of formulation stability, polyethylene glycol is particularly preferred.

[0082] <Solubilizer> Solubilizers are added, for example, to make the dosage form a liquid. Examples of solubilizers used include water and organic solvents. Specific examples of organic solvents include ethanol, n-propanol, isopropanol, methyl cellosolve, ethyl cellosolve, methyl carbitol, ethyl carbitol, benzyl alcohol, phenethyl alcohol, γ-phenylpropyl alcohol, cinnamon alcohol, anise alcohol, p-methylbenzyl alcohol, α-dimethylphenethyl alcohol, α-phenylethanol, ethylene glycol phenyl ether (phenoxyethanol), phenoxyisopropanol, 2-benzyloxyethanol, N-alkylpyrrolidone, alkylene carbonate, alkyl ethers, etc. One solubilizer may be used alone, or two or more solubilizers may be used in combination. Among these, water is preferred because it has excellent ability to dissolve other components in the first agent. When water is used as the solvent, the water content in the mixture (content at the time of use) is preferably 40% by mass or more, and more preferably 50% by mass or more.

[0083] <Water-soluble polymer> Water-soluble polymers provide the oxidative hair dye with an appropriate viscosity. Therefore, the oxidative hair dye may contain water-soluble polymers within a range that does not hinder the effects of the present invention. Examples of water-soluble polymers include natural polymers, semi-synthetic polymers, synthetic polymers, and inorganic polymers. Specific examples of natural polymers include guar gum, locust bean gum, quince seed, carrageenan, galactan, gum arabic, tragacanth gum, pectin, mannan, xanthan gum, dextran, succinoglucan, curdlan, hyaluronic acid, gelatin, casein, albumin, collagen, dextrin, triglucopolysaccharide (pullulan), etc.

[0084] Specific examples of semi-synthetic polymers include, for example, methylcellulose, ethylcellulose, hydroxyethylcellulose, hydroxyethylcellulose dimethyldiallylammonium chloride, hydroxypropylcellulose, carboxymethylcellulose, carboxymethylcellulose sodium, hydroxypropylmethylcellulose, cationized cellulose, cationized guar gum, starch phosphate esters, propylene glycol alginate esters, alginates, and the like.

[0085] Specific examples of synthetic polymers include polyvinyl caprolactam, polyvinyl alcohol (PVA), polyvinylpyrrolidone (PVP), vinylpyrrolidone-vinyl acetate (VP / VA) copolymer, polyvinyl butyral, polyvinyl methyl ether, carboxyvinyl polymer, sodium polyacrylate, polyacrylamide, polyethylene oxide, ethylene oxide-propylene oxide block copolymer, acrylic acid / alkyl acrylate copolymer, polydimethylmethylenepyrrolidinium chloride (polyquaternium-6) (Marquardt 100: manufactured by Merck), a semi-ester of itaconic acid and polyoxyethylene (hereinafter referred to as "POE") alkyl ether, or an ester of methacrylic acid and POE alkyl ether, and a copolymer consisting of at least one monomer selected from acrylic acid, methacrylic acid, and their alkyl esters. One type of water-soluble polymer may be used alone, or two or more types of water-soluble polymers may be used in combination.

[0086] The pH of an oxidative hair dye is preferably alkaline, for example, preferably 8.5 or higher, more preferably 8.75 or higher, and even more preferably 9.0 or higher. A pH of 8.5 or higher in an oxidative hair dye can provide a superior hair dyeing effect. The pH of oxidative hair dyes can be adjusted using acids such as phosphoric acid or alkalis such as sodium hydroxide. The pH of the oxidative hair dye of the present invention is measured in a 10% solution of a 1:1 mixture of the first and second agents. The pH can be measured using a pH meter such as the HORIBA pH-METER F-22.

[0087] The viscosity of the oxidative hair dye of the present invention is not particularly limited, but the viscosity at 25°C is, for example, 1,000 to 100,000 mPa·s. From the viewpoint of suppressing dripping, the lower limit is preferably 2,000 mPa·s or more, more preferably 5,000 mPa·s or more, and even more preferably 10,000 mPa·s or more. From the viewpoint of ease of application to hair, the upper limit is preferably 50,000 mPa·s or less, more preferably 40,000 mPa·s or less, and even more preferably 30,000 mPa·s or less. The viscosity of the oxidative hair dye can be adjusted by adding anionic surfactants, cationic surfactants, or thickeners such as water-soluble polymers. The mixed viscosity of the oxidative hair dye can be measured using a B-type viscometer such as a TVB-10 viscometer, and can be measured using a rotor suitable for each viscosity under conditions of 25°C and 1 minute. [Examples]

[0088] Next, the present invention will be specifically described with reference to examples and comparative examples. The present invention is not limited to the configurations described in the Examples section, nor is the scope of the present invention limited by these examples.

[0089] [Evaluation of oxidative hair dyes] (Preparation of oxidative hair dye) As an oxidative hair dye, a two-part oxidative hair dye was prepared by preparing a cream-like first agent containing the components shown in Tables 1 to 5, and an emulsion-like second agent containing the components shown in Table 6, according to conventional methods. In the following tables, the numerical values ​​in the columns indicating each component represent the content of that component, and the unit is mass %. In the "Component" column of each table, the notations (A) to (C) indicate the compounds corresponding to each of the (A) to (C) components described in the claims and specification of this application.

[0090] In the table below, 2,4-diaminophenoxyethanol and 1-hydroxyethyl-4,5-diaminopyrazole are obtained by neutralizing the raw materials, 2,4-diaminophenoxyethanol hydrochloride and 1-hydroxyethyl-4,5-diaminopyrazole sulfate, with NaOH as a pH adjuster. 2,4-diaminophenoxyethanol hydrochloride produces 2 moles of hydrochloric acid per mole, and 1-hydroxyethyl-4,5-diaminopyrazole sulfate produces 1 mole of sulfuric acid per mole. Since these are divalent ions, neutralization was achieved by mixing them in a ratio of 2,4-diaminophenoxyethanol hydrochloride:NaOH = 1:2 moles and 1-hydroxyethyl-4,5-diaminopyrazole sulfate:NaOH = 1:2 moles. In other words, the first agent contains 2,4-diaminophenoxyethanol and 1-hydroxyethyl-4,5-diaminopyrazole in a free state.

[0091] (Transferability after being left for a specified time) For each example and comparative example, the first and second agents were mixed in a 1:1 mass ratio to prepare the oxidative hair dye mixture for each example. 3g of the resulting mixture was applied using a brush to 1g of a 10cm long white hair bundle sample (manufactured by Beaulux Co., Ltd.) (hereinafter simply referred to as "hair bundle") and left at 30°C for 40 minutes. Afterward, the mixture adhering to the hair bundle was rinsed off with water, and the hair bundle was shampooed twice with shampoo (Bigen Treatment Shampoo, manufactured by Hoyu Co., Ltd.) and rinsed once with rinse (Bigen Treatment Rinse, manufactured by Hoyu Co., Ltd.). The treated hair bundle was then sandwiched between white cotton cloths for JIS colorfastness testing (compliant with JIS L0803), and a 5kg load was applied from above the cotton cloth. Ten panelists visually observed the degree of soiling on the cotton cloth one minute after the load was applied and evaluated it according to the following criteria. The average of the evaluation scores from the 10 panelists was rounded to obtain the evaluation score for the oxidative hair dye used in each example. The results are shown in the "Color Transferability" column of Tables 1 to 5. (Criteria for evaluating transferability) 5: Very resistant to stains 4: Dirt is not easily noticeable 3: Stain is hardly noticeable 2: Stain is noticeable 1: Very noticeable dirt

[0092] (Dyeing power, saturation, and decolorization performance) For each example and comparative example, the first and second agents were mixed in a 1:1 mass ratio to prepare the oxidative hair dye mixture for each example. 3 g of the resulting mixture was applied using a brush to 1 g of a 10 cm long sample of white hair (manufactured by Beaulux Co., Ltd.) (hereinafter simply referred to as "hair bundle") for evaluation, and left at 30°C. 40 minutes after application of the mixture to the hair bundle, the mixture adhering to the hair bundle was rinsed off with water, and the hair bundle was shampooed twice with shampoo (Bigen Treatment Shampoo, manufactured by Hoyu Co., Ltd.) and rinsed once with rinse (Bigen Treatment Rinse, manufactured by Hoyu Co., Ltd.). Subsequently, the hair bundle was dried with warm air to obtain the dyed hair bundles for each example.

[0093] For each hair bundle that underwent the hair dyeing treatment, the dyeing power, saturation, and decolorization performance were evaluated 24 hours after the treatment according to the method described below.

[0094] (Method for evaluating hair dyeing power) For each hair strand treated with dye as described above, 10 panelists visually observed the dyeing state under a standard light source. In the visual evaluation, the dyeing power was assessed using the following evaluation criteria, and the average of the evaluation scores from the 10 panelists was rounded to the first decimal place to determine the evaluation score of the oxidative hair dye used for each example. The results are shown in the "Dyeing Power" column of Tables 1 to 5. (Evaluation criteria for hair dyeing power) 5: It has very strong hair dyeing power. 4: It has high hair dyeing power. 3: Has a slightly higher hair dyeing power. 2: It has poor hair dyeing power. 1: It has very low hair dyeing power.

[0095] (Method for evaluating saturation) The saturation of the dyed hair bundles of Example 1 and Comparative Example obtained as described above was visually observed by 10 panelists under a standard light source. In the visual evaluation, the saturation was evaluated according to the following evaluation criteria, and the average value of the evaluation scores of the 10 panelists was rounded to the first decimal place to determine the evaluation score of the oxidative hair dye used in each example. The results are shown in the "Saturation" column of Tables 1 to 5. (Saturation evaluation criteria) 5: It is dyed very vividly. 4: It is vividly colored. 3: It is dyed in a fairly vivid color. 2: It's dull and discolored. 1: It's quite dull and discolored.

[0096] (Method for evaluating destaining performance) To each of the dyed hair strands obtained as described above, a decolorization treatment was performed using "Rece Powder Bleach" (manufactured by Hoyu Co., Ltd.), a common bleaching and decolorizing agent, in accordance with the standard procedure to obtain decolorized hair strands.

[0097] Then, the 10 panelists visually observed the color tone of the decolorized hair strands under standard lighting conditions, comparing them to untreated white hair strands to determine whether the decolorization was effective. The results of these comparative observations were combined to evaluate the decolorization performance, and the following criteria were used for the evaluation: "5 points: Excellent decolorization performance," "4 points: Good decolorization performance," "3 points: Fairly good decolorization performance," "2 points: Fairly poor decolorization performance," and "1 point: Poor decolorization performance." The average score was calculated from each panelist's score and evaluated according to the following criteria. The results are shown in the "Decolorization Performance" column of Tables 1 to 5. (Evaluation criteria for destaining performance) 6: Average score of 4.7 or higher (Excellent) 5: Average score is between 4.0 and 4.7 (Excellent) 4: Average score is between 3.3 and 4.0 (Good) 3: Average score is between 2.6 and 3.3 (acceptable) 2: Average score between 1.9 and 2.6 (slightly poor) 1: Average score is less than 1.9 (Poor)

[0098] [Table 1]

[0099] [Table 2]

[0100] [Table 3]

[0101] [Table 4]

[0102] [Table 5]

[0103] [Table 6]

[0104] As shown in Tables 1 to 4, the oxidative hair dye of the present invention in the examples received a rating of 3 to 5 for color transfer, and in all examples, it showed good results of "almost no noticeable staining" or better. Next, for dyeing power, the rating was 3 to 5, and in all examples, it showed good results of "slightly high dyeing power" or better. Next, for saturation, the rating was 5, and in Example 1, it showed good results of "very vividly dyed". Furthermore, for decolorization performance, the rating was 3 to 6, and in all examples, it showed good results of "acceptable" or better. In other words, all examples showed good results in the evaluation of color transfer, dyeing power, and decolorization performance. In addition, in Example 1, it showed good results not only in color transfer, dyeing power, and decolorization performance, but also in saturation.

[0105] As shown in Tables 1 to 5, when comparing the Example with Comparative Example 1, Comparative Example 1 differs from the Example in that it does not have a (A) coupler. Comparative Example 1 lacked (A) a coupler, and therefore (B) could not suppress the color transfer of the compound shown in general formula (1) to the fabric. Furthermore, because the dyeing was performed by polymerization of dye intermediates, decolorization was not easy. Consequently, the color transfer and decolorization performance were poor. On the other hand, as described above, the Example yielded excellent results in all evaluations of color transfer, dyeing power, saturation, and decolorization performance.

[0106] As shown in Tables 1 to 5, when comparing the Examples with Comparative Example 2, Comparative Example 2 differs from the Examples in that it does not contain the compound shown in (B) general formula (1). Comparing Example 7 with Comparative Example 2, the color transfer evaluation showed that Example 7 was "3" while Comparative Example 2 was "4," indicating that the color transfer was caused by the compound shown in (B) general formula (1). Since all examples showed high evaluations of 3 to 5 in the color transfer evaluation, the oxidative hair dye of the present invention can suppress color transfer caused by the compound shown in (B) general formula (1).

[0107] As shown in Tables 1 to 5, when comparing the Examples with Comparative Example 3, Comparative Example 3 differs from the Examples in that the mass ratio (B / A) of the content of the compound shown in general formula (1) to the content of the coupler is greater than 0.5. Comparative Example 3 has a (B / A) ratio greater than 0.5, resulting in poor evaluations of both color transfer and color removal performance, both rated as "1". On the other hand, the Examples show evaluations of "3 to 5" for color transfer and "3 to 6" for color removal performance, indicating high evaluations in both areas. Therefore, it can be seen that the oxidative hair dye of the present invention can suppress color transfer caused by the compound shown in (B) general formula (1), and also exhibits excellent color removal performance.

[0108] As shown in Tables 1 to 5, when comparing the Examples with Comparative Example 4, Comparative Example 4 differs from the Examples in that the content of (A) coupler is not 0.3% by mass or more. Comparative Example 4 had poor hair dyeing power and saturation because the content of (A) coupler was not 0.3% by mass or more. On the other hand, all of the Examples were found to have good hair dyeing power.

[0109] Comparing Example 1 with Examples 2-5, although different compounds were used as (A) couplers, excellent results were observed in terms of color transfer, dyeing power, and color removal performance. This indicates that various couplers can be used as (A) couplers in the oxidative hair dye of the present invention. Furthermore, although Example 1 uses (A-1)2,4-diaminophenoxyethanol as the (A) coupler, it shows superior results in terms of hair dyeing power compared to Examples 3-5. From this, it can be seen that (A-1)2,4-diaminophenoxyethanol and / or its salts are preferable as the (A) coupler.

[0110] Comparing Examples 1, 6, and 7, the content of the compound shown in (B) General Formula (1) differs. As the content of the compound shown in (B) General Formula (1) decreases, the evaluation of color transfer improves. From this, it can be seen that, from the viewpoint of suppressing color transfer, it is preferable for the oxidative hair dye of the present invention to have a lower content of the compound shown in (B) General Formula (1).

[0111] Comparing Examples 1, 8, 9, and 10, the mass ratio (B / A) of the content of the compound shown in general formula (1) to (A) the content of the coupler differs. It can be seen that as (B / A) decreases, the evaluation of the stain transfer and destaining performance improves. Furthermore, comparing Examples 1 and 8, although the content of the compound shown in (B) general formula (1) differs, Example 1 has a similar content of "0.2% by mass" and Example 8 has a similar content of "0.15% by mass". On the other hand, the content of (A) coupler is "3.5% by mass" in Example 1 and "0.6% by mass" in Example 8, with Example 1 containing approximately six times more than Example 8. However, both Examples 1 and 8 showed excellent results in terms of color transfer and color removal performance, and also showed good results in terms of hair dyeing power, with Example 1 scoring "5" and Example 8 scoring "3". Therefore, it can be seen that the oxidative hair dye of the present invention can exhibit sufficient hair dyeing power by containing 0.3% by mass or more of (A) coupler.

[0112] Examples 11-13 contain multiple compounds as the (A) coupler, but they show good results in all evaluations of color transfer, hair dyeing power, and color removal performance. From this, it can be seen that the oxidative hair dye of the present invention can use (A-1) 2,4-diaminophenoxyethanol and / or its salts in combination with other couplers as the (A) coupler. Furthermore, comparing Examples 12 and 13, in Example 12 the content of (A-1) 2,4-diaminophenoxyethanol and / or its salts in the total content of the (A) coupler is 25% by mass, while in Example 13 it is 33% by mass. The result for hair dyeing power is "4" for Example 12, but "5" for Example 13. Thus, it can be seen that the hair dyeing power is improved when the content of (A-1) 2,4-diaminophenoxyethanol and / or its salts in the (A) coupler is 30% by mass or more. [Industrial applicability]

[0113] The oxidative hair dye of the present invention can be used as a hair dye for dyeing human hair such as scalp hair, beard, eyebrows, and leg hair. It may also be used to dye the body hair of animals such as pets. The oxidative hair dye of the present invention can be used as a hair dye for coloring in beauty salons, barber shops, etc., and as a hair dye for self-coloring.

Claims

1. (A) A coupler, and (B) an oxidative hair dye containing a compound shown in general formula (1), The content of the aforementioned (A) coupler is 0.3% by mass or more, The mass ratio (B / A) of the content of the coupler (A) and the content of the compound shown in general formula (1) (B) is 0.5 or less. 【Chemistry 1】 (Here, R represents a linear or branched alkyl group having 1 to 6 carbon atoms, a linear or branched mono- or polyhydroxyalkyl group having 2 to 6 carbon atoms, or a linear or branched mono- or polyaminoalkyl group.) The (A) coupler comprises at least one of 2,4-diaminophenoxyethanol, 5-amino-o-cresol, 2,6-diaminopyridine, 5-(2-hydroxethylamino)-2-methylphenol, and salts thereof. An oxidative hair dye characterized in that the compound shown in (B) general formula (1) above comprises 1-hydroxyethyl-4,5-diaminopyrazole and / or a salt thereof.

2. The oxidative hair dye according to claim 1, characterized in that the compound shown in (B) general formula (1) is 1-hydroxyethyl-4,5-diaminopyrazole and / or its sulfate.

3. The oxidative hair dye according to claim 1 or 2, characterized in that the content of the compound shown in (B) general formula (1) is 0.3% by mass or less.

4. The oxidative hair dye according to any one of claims 1 to 3, characterized in that the mass ratio (C / A) of the content of the coupler (A) and the content of the dye intermediate (C) contained in the oxidative hair dye is 0.4 or less.

5. The oxidative hair dye according to any one of claims 1 to 4, characterized in that the (A) coupler contains (A-1) 2,4-diaminophenoxyethanol and / or a salt thereof, and the content of (A-1) 2,4-diaminophenoxyethanol and / or a salt thereof in the (A) coupler is 30% by mass or more.

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