JP7589971B2 - Acidic hair dye composition - Google Patents

Description

This disclosure relates to an acidic hair dye composition.

Hair dye compositions used as semi-permanent hair dyes mainly contain acid dyes as dyes for dyeing hair to the desired color tone. Among acid dyes, black 401 is used in hair dye compositions intended for dyeing hair in darker colors, such as brown to black, as shown in Patent Documents 1 to 3.

Patent No. 5931378 Patent No. 5495475 Patent No. 4361197

According to the inventor's research, in order to achieve a more vivid color tone, other acid dyes are often used in combination with Black 401. In the above Patent Documents 1 to 3, Purple 401 is also used in combination with Black 401.

However, it was found that the hair dye composition containing Black 401 and Purple 401 may cause the color tone of dyed hair to change over time due to long-term storage.
One aspect of the present disclosure provides a hair dye composition that exhibits excellent hair color stability when dyed even after long-term storage.

One aspect of the present disclosure is an acidic hair dye composition that contains (A) Purple 401. The acidic hair dye composition does not contain (B) Black 401, or contains (B) Black 401 and the mass ratio (A)/(B) of the content of (A) Purple 401 in the acidic hair dye composition to the content of (B) Black 401 in the acidic hair dye composition is 15 or more. The acidic hair dye composition also contains (C) acid.

In one embodiment of the present disclosure, the acid (C) may contain at least one selected from the group consisting of levulinic acid, succinic acid, phosphoric acid, and pyrrolidone carboxylic acid.
In one aspect of the present disclosure, the (C) acid may include levulinic acid.

In one embodiment of the present disclosure, the mass ratio (A)/(C) of the content of (A) Purple 401 in the acidic hair dye composition to the content of (C) acid in the acidic hair dye composition may be 0.01 or more and 0.2 or less.

In one embodiment of the present disclosure, the composition may further contain (D) at least one selected from the group consisting of HC Yellow 2, HC Yellow 4, HC Orange 1, HC Red 1, HC Red 3, 4-amino-3-nitrophenol, 3-nitro-p-hydroxyethylaminophenol, 2-hydroxyethylpicramic acid, hydroxyethyl-2-nitro-p-toluidine, 2-amino-6-chloro-4-nitrophenol, and 4-hydroxypropylamino-3-nitrophenol.

According to one aspect of the present disclosure, a hair dye composition is provided that exhibits excellent color stability when dyeing hair even after long-term storage.

An acidic hair dye composition according to one embodiment of the present disclosure contains (A) Purple 401 and does not contain (B) Black 401, or contains (B) Black 401 and the mass ratio (A)/(B) of the content of (A) Purple 401 in the acidic hair dye composition to the content of (B) Black 401 in the acidic hair dye composition is 15 or more, and contains (C) acid.

Such a hair dye composition has excellent color stability when dyeing hair even after long-term storage, as described below.
According to the inventor's investigations, it has been found that the reason why the color tone of a hair dye composition containing (A) Purple 401 and (B) Black 401 changes over time when stored for a long period of time is that (B) Black 401 does not have good stability as a dye.

Therefore, by deliberately not including (B) Black 401, which is often used to achieve a darker color tone, it is possible to obtain a hair dye composition that has excellent color tone stability even after long-term storage.
On the other hand, even when (B) Black 401 is contained, by making the mass ratio (A)/(B) of the content of (A) Purple 401 in the hair dye composition to the content of (B) Black 401 in the hair dye composition to be 15 or more (hereinafter simply referred to as "mass ratio (A)/(B)") and making the content of (A) Purple 401 significantly higher than the content of (B) Black 401, a hair dye composition with excellent color stability even after long-term storage can be obtained.

The hair dye composition is an acidic hair dye composition containing (C) acid. The presence of (C) acid and the adjustment of the hair dye composition to an acidic state improves the dye stability of acidic dyes such as (A) Purple 401 and (B) Black 401. As a result, the resulting hair dye composition has excellent color stability even after long-term storage.

Furthermore, the hair dye composition makes it easy to achieve a desired color tone, as described below.
Since (A) Purple 401 has a strong coloring, when it is used in combination with other dyes such as component (D) described below, the coloring of the other dyes is overpowered by the coloring of (A) Purple 401, and the purple to blue coloring of (A) Purple 401 tends to be strong. This tendency is particularly strong when the hair dye composition does not contain (B) Black 401.

However, (C) acids, particularly levulinic acid, succinic acid, phosphoric acid, and pyrrolidone carboxylic acid, as described below, can suppress the color development of (A) Purple 401 relative to other dyes such as component (D). Therefore, the purple to blue color of (A) Purple 401 is suppressed, and the color of other dyes such as component (D) can be brought out, making it easier to achieve the desired color tone.

The acidic hair dye composition according to one embodiment of the present disclosure will be described in detail below.
[(A) Purple 401]
Component (A), Purple 401 (C.I. 60730), is a purple acid dye.

The content of (A) Purple 401 in the hair dye composition is preferably 0.01% by mass or more, and particularly 0.05% by mass or more. When the content of (A) Purple 401 is 0.01% by mass or more, the hair dye composition has excellent hair dyeing power. In addition, since (A) Purple 401 has high stability as a dye, when the content of (A) Purple 401 is 0.01% by mass or more, the color stability of the hair dye composition is further improved. In addition, the content of (A) Purple 401 is preferably 0.3% by mass or less, and particularly 0.2% by mass or less. When the content of (A) Purple 401 is 0.3% by mass or less, the purple to blue color tone caused by (A) Purple 401 is further suppressed, making it easier to achieve the desired color tone.

[(B) Black 401]
Black 401 (C.I. 20470), which is component (B), is a black acid dye.
As described above, (B) Black 401 is not contained in the hair dye composition, or if it is contained, it is contained so that the mass ratio (A)/(B) is not less than 15. Since the color stability of the hair dye composition is particularly excellent, it is preferable that (B) Black 401 is not contained in the hair dye composition.

When (B) Black 401 is contained in the hair dye composition, the mass ratio (A)/(B) is 15 or more as described above. It is more preferable that the mass ratio (A)/(B) is 20 or more. When the mass ratio (A)/(B) is 20 or more, the color stability of the hair dye composition is further improved.

When (B) Black 401 is contained in the hair dye composition, the content of (B) Black 401 in the hair dye composition is preferably 0.2% by mass or less, and particularly preferably 0.1% by mass or less. When the content of (B) Black 401 is 0.2% by mass or less, the color stability of the hair dye composition is further improved.

[(C) Acid]
The acid (C) component improves the dye stability of acid dyes such as (A) Purple 401 and (B) Black 401, and improves the color stability of the hair dye composition. In addition, the acid (C) improves the color development of the acid dye, while suppressing the color development of (A) Purple 401 relative to other dyes such as the component (D), as described above. Therefore, the purple to blue color of (A) Purple 401 is suppressed, and the color of the other dyes can be brought out, making it easier to achieve the desired color tone.

(C) Acids include organic acids and inorganic acids. Inorganic acids include, for example, phosphoric acid, hydrochloric acid, nitric acid, sulfuric acid, boric acid, and carbonic acid. Phosphoric acid includes orthophosphoric acid, polyphosphoric acid, pyrophosphoric acid, and metaphosphoric acid. Organic acids include, for example, hydroxy acids, keto acids, and dicarboxylic acids. Organic acids having 6 or less carbon atoms are preferred. Hydroxy acids include, for example, citric acid, tartaric acid, lactic acid, malic acid, glycolic acid, benzoic acid, gluconic acid, glucuronic acid, aspartic acid, and glutamic acid. Keto acids include, for example, levulinic acid, pyruvic acid, and pyrrolidone carboxylic acid. Dicarboxylic acids include, for example, succinic acid, malonic acid, adipic acid, fumaric acid, and maleic acid.

The (C) acid preferably contains at least one selected from the group consisting of hydroxy acids, keto acids, and phosphoric acids, since it is highly effective in suppressing the purple to blue color caused by (A) Purple 401, and more preferably contains at least one selected from the group consisting of levulinic acid, succinic acid, phosphoric acid, and pyrrolidone carboxylic acid. The (C) acid preferably contains levulinic acid, since it is particularly excellent in the color stability of the hair dye composition and is more effective in suppressing the purple to blue color caused by (A) Purple 401. In addition, the (C) acid preferably contains levulinic acid and pyrrolidone carboxylic acid, since the pH of the hair dye composition is more likely to be stabilized than when levulinic acid is used alone.

The mass ratio (A)/(C) of the content of (A) Purple 401 in the hair dye composition to the content of (C) acid in the hair dye composition (hereinafter simply referred to as "mass ratio (A)/(C)") is preferably 0.01 or more, particularly 0.02 or more. If the content of (C) acid is excessively high compared to the content of (A) Purple 401, the color development of (A) Purple 401 due to (C) acid becomes too strong, and the purple to blue color due to (A) Purple 401 tends to be strong. If the mass ratio (A)/(C) is 0.01 or more, the blending balance of (A) Purple 401 and (C) acid is good, the purple to blue color due to (A) Purple 401 is suppressed, and the desired color tone is more easily achieved.

The mass ratio (A)/(C) is preferably 0.2 or less, particularly 0.15 or less. Even if the content of (C) acid is excessively small compared to the content of (A) Purple 401, the effect of (C) acid in suppressing the relative color development of (A) Purple 401 with respect to other dyes such as the (D) component is reduced, and the purple to blue color due to (A) Purple 401 tends to be strong. When the mass ratio (A)/(C) is 0.2 or less, the blending balance of (A) Purple 401 and (C) acid is good, the purple to blue color due to (A) Purple 401 is suppressed, and the desired color tone is more easily achieved. Note that the content of (C) acid in the hair dye composition referred to here refers to the total content of all (C) acids in the hair dye composition.

The content of (C) acid in the hair dye composition is preferably 0.3% by mass or more, and particularly 0.5% by mass or more. When the content of (C) acid is 0.3% by mass or more, the color development of the acid dye is further improved and the color stability of the hair dye composition is further improved. In addition, the content of (C) acid is preferably 5% by mass or less, and particularly 2% by mass or less. When the content of (C) acid is 5% by mass or less, excessive color development of the acid dye is further suppressed. As a result, the purple to blue color tone of (A) Purple 401 is further suppressed, making it easier to achieve the desired color tone.

[Component (D)]
The hair dye composition may further contain, as component (D), at least one selected from the group consisting of HC Yellow No. 2, HC Yellow No. 4, HC Orange No. 1, HC Red No. 1, HC Red No. 3, 4-amino-3-nitrophenol, 3-nitro-p-hydroxyethylaminophenol, 2-hydroxyethylpicramic acid, hydroxyethyl-2-nitro-p-toluidine, 2-amino-6-chloro-4-nitrophenol, and 4-hydroxypropylamino-3-nitrophenol.

The (D) components are all non-ionic dyes. Since the (D) component does not easily stain the scalp or skin, the resulting hair dye composition is more effective at preventing skin staining when the desired color tone is adjusted using a combination of an acid dye and the (D) component, rather than using only an acid dye, which is relatively easy to stain the skin.

In addition, by using component (D) in combination with (A) Purple 401, darker colors, particularly brown to black tones, can be easily achieved. For example, in order to achieve brown to black tones, the hair dye composition preferably contains at least one yellow dye selected from the group consisting of HC Yellow 2, HC Yellow 4, and hydroxyethyl-2-nitro-p-toluidine, and at least one red to orange dye selected from the group consisting of HC Orange 1, HC Red 1, HC Red 3, 4-amino-3-nitrophenol, 3-nitro-p-hydroxyethylaminophenol, 2-hydroxyethylpicramic acid, 2-amino-6-chloro-4-nitrophenol, and 4-hydroxypropylamino-3-nitrophenol. Of the dyes listed as red to orange dyes, HC Orange 1, 4-amino-3-nitrophenol, and 2-amino-6-chloro-4-nitrophenol are orange dyes, and the others are red dyes.

The mass ratio (D)/(A) of the content of the (D) component in the hair dye composition to the content of the (A) Purple 401 in the hair dye composition (hereinafter simply referred to as the "mass ratio (D)/(A)") is preferably 0.2 or more, particularly 0.5 or more, and even more preferably 0.7 or more. When the mass ratio (D)/(A) is 0.2 or more, the background staining is further suppressed. In addition, the mass ratio (D)/(A) is preferably 5 or less, particularly 2 or less, and even more preferably 1.5 or less. When the mass ratio (D)/(A) is 5 or less, the blending balance between the (A) Purple 401 and the (D) component is good, and it is easier to achieve the desired color tone. The content of the (D) component in the hair dye composition referred to here refers to the total content of the entire (D) component in the hair dye composition.

The content of component (D) in the hair dye composition is preferably 0.01% by mass or more, particularly 0.02% by mass or more, and even more preferably 0.03% by mass or more. When the content of component (D) is 0.01% by mass or more, skin staining is further suppressed. In addition, the content of component (D) is preferably 1% by mass or less, particularly 0.8% by mass or less, and even more preferably 0.6% by mass or less. When the content of component (D) is 1% by mass or less, the blending balance between (A) Purple 401 and component (D) is good, and the desired color tone is more easily achieved.

[pH of hair dye composition]
The pH of the hair dye composition is preferably 5 or less, particularly 4 or less. When the pH of the hair dye composition is 5 or less, the hair dyeing power of the hair dye composition is improved. When the pH of the hair dye composition is 5 or less, the dye stability of the acid dye such as (A) Purple 401 and (B) Black 401 is further improved, and the color stability of the hair dye composition is further improved. When the pH of the hair dye composition is 2.5 or more, particularly 3 or more. When the pH of the hair dye composition is 2.5 or more, irritation to the scalp is suppressed.

The pH of the hair dye composition is the pH at 25° C. when the hair dye composition is dissolved in water at a concentration of 10% by mass.
[Dyes other than those mentioned above]
The hair dye composition may contain dyes other than (A) Purple 401, (B) Black 401, and (D) component, to the extent that the above-mentioned effects are not impaired. Examples of dyes include acid dyes (excluding (A) Purple 401 and (B) Black 401), nitro dyes (excluding those listed as the above-mentioned (D) component), basic dyes (cationic dyes), disperse dyes, etc.

Examples of acid dyes include Red 2, Red 3, Red 102, Red 104 (1), Red 105 (1), Red 106, Red 201, Red 227, Red 230 (1), Red 230 (2), Red 231, Red 232, Red 401, Red 502, Red 503, Red 504, Red 506, Yellow 4, Yellow 5, Yellow 202 (1), Yellow 202 (2), Yellow 203, Yellow 402, Yellow 403 (1), Yellow 406, Yellow 407, Orange 205, Orange 207, Orange 402, Green 3, Green 2 04, Green 205, Green 401, Green 402, Blue 1, Blue 2, Blue 202, Blue 203, Blue 205, Brown 201, Acid Blue 1, Acid Blue 3, Acid Blue 62, Acid Black 52, Acid Brown 13, Acid Green 50, Acid Orange 6, Acid Red 14, Acid Red 35, Acid Red 73, Acid Red 184, Brilliant Black 1, etc.

Examples of nitro dyes include 4-nitro-o-phenylenediamine, 2-nitro-p-phenylenediamine, 2-amino-4-nitrophenol, 2-amino-5-nitrophenol, N,N'-bis(2-hydroxyethyl)-2-nitro-p-phenylenediamine, picramic acid, picric acid, and their salts, HC Blue No.2, HC Blue No.4, HC Blue No.5, HC Blue No.6, HC Blue No.8, HC Blue No.9, HC Blue No.10, HC Blue No.11, HC Blue No.12, HC Blue No.13, HC Blue No.14, HC Blue No.15, HC Blue No.16, HC Blue No.18, HC Blue No.19, HC Brown No.1, HC Brown No.2, HC Green No.1, HC Orange No.2, HC Orange No.3, HC Orange No.5, HC Orange No.7, HC Red No.7, HC Red No.8, HC Red No.9, HC Red No.10, HC Red No.11, HC Red No.13, HC Red No.14, HC Red No.18, HC Violet No.1, HC Violet No.2, HC Violet No.3, HC Yellow No.5, HC Yellow No.6, HC Yellow No.7, HC Yellow No.8, HC Yellow No.9, HC Yellow No.10, HC Yellow No.11, HC Yellow No.12, HC Yellow No.13, HC Yellow No.14, HC Yellow No.15, HC Yellow No.16, HC Yellow No.18, etc.

Examples of basic dyes (cationic dyes) include Red 213, Red 214, Basic Blue 3, Basic Blue 6, Basic Blue 7, Basic Blue 9, Basic Blue 26, Basic Blue 41, Basic Blue 75, Basic Blue 99, Basic Blue 124, Basic Brown 1, Basic Brown 4, Basic Orange 1, Basic Orange 2, Basic Red 1, Basic Red 2, Basic Red 22, Basic Red 46, Basic Red 118, Basic violet 2, Basic Violet 10, Basic Violet 11:1, Basic Violet 16, Basic Yellow 11, Basic Yellow 28, Basic Yellow 57, and Basic Yellow 87.

Examples of 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.

Other dyes include, for example, 1-amino-4-methylanthraquinone, 1,4-diaminoanthraquinone, and their salts, as well as dyes designated by the "Ministry Ordinance Specifying Tar Dyes That Can Be Used in Pharmaceuticals, etc." (Notification of 1966, Ministry of Health and Welfare).

[Other ingredients]
The hair dye composition may contain other ingredients in addition to the above ingredients, if necessary.
Examples of the other components include solvents, oily components, polyhydric alcohols, surfactants, water-soluble polymers, pH adjusters, sugars, preservatives, chelating agents, stabilizers, amino acids, inorganic salts, animal, plant or microbial extracts, herbal extracts, vitamins, fragrances, antioxidants, ultraviolet absorbers, etc. Among these other components, one type may be contained alone, or two or more types may be contained in combination.

The above-mentioned solvents can be blended, for example, to make the hair dye composition into a desired state such as a liquid or emulsion. Examples of the solvent include water such as purified water, organic solvents, and the like. Examples of the organic solvent include ethanol, n-propanol, isopropanol, methyl cellosolve, ethyl cellosolve, methyl carbitol, ethyl carbitol, benzyl alcohol, benzyloxyethanol, phenethyl alcohol, γ-phenylpropyl alcohol, cinnamic alcohol, anise alcohol, p-methylbenzyl alcohol, α-dimethylphenethyl alcohol, α-phenylethanol, ethylene glycol phenyl ether, phenoxyisopropanol, 2-benzyloxyethanol, N-alkylpyrrolidone, alkylene carbonate, and the like. Of these solvents, one type may be contained alone, or two or more types may be contained in combination. Of these, it is preferable that water is contained as the solvent. The content of water is, for example, 50% by mass or more.

Examples of the oily component include fats and oils, waxes, hydrocarbons, higher fatty acids, higher alcohols, alkyl glyceryl ethers, esters, silicones, and the like.
Examples of fats and oils include Argania spinosa kernel oil, olive oil, camellia oil, shea butter, almond oil, safflower oil, sunflower oil, soybean oil, cottonseed oil, sesame oil, corn oil, rapeseed oil, rice bran oil, rice germ oil, grape seed oil, avocado oil, macadamia nut oil, castor oil, coconut oil, evening primrose oil, apricot kernel oil, persic oil, peach kernel oil, palm oil, and egg yolk oil.

Examples of waxes include beeswax, candelilla wax, carnauba wax, jojoba oil, and lanolin.
Examples of the hydrocarbon include paraffin, olefin oligomer, polyisobutene, hydrogenated polyisobutene, squalane, polybutene, polyethylene, microcrystalline wax, petrolatum, liquid paraffin, light isoparaffin, light liquid isoparaffin, isoparaffin, α-olefin oligomer, and synthetic squalane.

Examples of higher fatty acids include lauric acid, myristic acid, palmitic acid, stearic acid, behenic acid, isostearic acid, 12-hydroxystearic acid, oleic acid, and lanolin fatty acid.

Examples of higher alcohols include cetyl alcohol (cetanol), 2-hexyldecanol, stearyl alcohol, isostearyl alcohol, cetostearyl alcohol, oleyl alcohol, arachyl alcohol, behenyl alcohol, 2-octyldodecanol, lauryl alcohol, myristyl alcohol, decyltetradecanol, lanolin alcohol, etc.

Examples of alkyl glyceryl ethers include batyl alcohol, chimyl alcohol, selachyl alcohol, and isostearyl glyceryl ether.
Examples of esters include diisopropyl adipate, isopropyl myristate, cetyl octanoate, isononyl isononanoate, octyldodecyl myristate, isopropyl palmitate, stearyl stearate, myristyl myristate, isotridecyl myristate, 2-ethylhexyl palmitate, octyldodecyl ricinoleate, cholesteryl/lanosteryl fatty acids having 10 to 30 carbon atoms, cetyl lactate, lanolin acetate, ethylene glycol di-2-ethylhexanoate, pentaerythritol fatty acid esters, dipentaerythritol fatty acid esters, cetyl caprate, glyceryl tricaprylate, diisostearyl malate, dioctyl succinate, diethoxyethyl succinate, cetyl 2-ethylhexanoate, and hydrogenated castor oil isostearate.

Examples of silicones include dimethylpolysiloxane (dimethicone), methylphenylpolysiloxane, decamethylcyclopentasiloxane, dodecamethylcyclohexasiloxane, hydroxyl-terminated dimethylpolysiloxane (dimethiconol), highly polymerized silicones with an average degree of polymerization of 650 to 10,000, polyether-modified silicones (e.g., (PEG/PPG/butylene/dimethicone) copolymers), betaine-modified silicones, alkyl-modified silicones, alkoxy-modified silicones, mercapto-modified silicones, carboxy-modified silicones, and fluorine-modified silicones.

Among these oily components, one type may be contained alone, or two or more types may be contained in combination.
Examples of the polyhydric alcohol include glycol and glycerin. Examples of the glycol include ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, dipropylene glycol, polypropylene glycol, isoprene glycol, and 1,3-butylene glycol. Examples of the glycerin include glycerin, diglycerin, and polyglycerin. Of these polyhydric alcohols, one type may be contained alone, or two or more types may be contained in combination.

Examples of the surfactant include nonionic surfactants, anionic surfactants, cationic surfactants, and amphoteric surfactants.
Examples of the nonionic surfactant include fatty acid alkanolamide type nonionic surfactants, ester type nonionic surfactants, and alkyl glucosides.

Examples of fatty acid alkanolamide type nonionic surfactants include fatty acid alkanolamides and polyoxyalkylene fatty acid alkanolamides. Examples of fatty acid alkanolamides include coconut oil fatty acid monoethanolamide (cocamide MEA), coconut oil fatty acid diethanolamide, lauric acid monoethanolamide, lauric acid diethanolamide, lauric acid monoisopropanolamide, myristic acid monoethanolamide, myristic acid diethanolamide, stearic acid monoethanolamide, stearic acid diethanolamide, coconut oil fatty acid methylethanolamide, and the like. Examples of polyoxyethylene fatty acid alkanolamides include POE coconut oil fatty acid monoethanolamide, POE lauric acid monoethanolamide, POP myristic acid monoethanolamide, POP coconut oil fatty acid monoisopropanolamide, and the like. In the compound names, POE is an abbreviation for polyoxyethylene, and POP is an abbreviation for polyoxypropylene.

Examples of ester-type nonionic surfactants include POE sorbitan monooleate, POE sorbitan monostearate, POE sorbitan monopalmitate, POE sorbitan monolaurate, POE sorbitan trioleate, POE glycerin monostearate, POE glycerin monomyristate, POE sorbitol tetraoleate, POE sorbitol hexastearate, POE sorbitol monolaurate, POE sorbitol beeswax, polyethylene glycol monooleate, and polyethylene glycol monostearate. Examples of such additives include ricor, polyethylene glycol monolaurate, lipophilic glyceryl monooleate, lipophilic glyceryl monostearate, self-emulsifying glyceryl monostearate, sorbitan monooleate, sorbitan sesquioleate, sorbitan trioleate, sorbitan monostearate, sorbitan monopalmitate, sorbitan monolaurate, sucrose fatty acid esters, decaglyceryl monolaurate, decaglyceryl monostearate, decaglyceryl monooleate, and decaglyceryl monomyristate.

Alkyl glucosides include, for example, alkyl (C8-16) glucoside, polyoxyethylene methyl glucoside, polyoxyethylene dioleate methyl glucoside, etc.

Of these nonionic surfactants, it is preferable to include a fatty acid alkanolamide type nonionic surfactant, as this improves the hair dyeing power of the hair dye composition. Furthermore, among these nonionic surfactants, one type may be included alone, or two or more types may be included in combination.

Examples of anionic surfactants include alkyl ether sulfates, alkyl sulfates, alkyl ether sulfate ester salts, alkenyl ether sulfates, alkenyl sulfates, olefin sulfonates, alkanesulfonates, saturated or unsaturated fatty acid salts, alkyl or alkenyl ether carboxylates, α-sulfonic acid salts, N-acylamino acid surfactants, mono- or diester phosphate surfactants, sulfosuccinates, N-alkyloylmethyl taurine salts, and derivatives thereof. Examples of counterions of the anionic groups of these surfactants include sodium ions, potassium ions, triethanolamine, and the like. More specifically, examples of alkyl ether sulfate ester salts include sodium POE lauryl ether sulfate. Examples of alkyl sulfate salts include sodium lauryl sulfate and sodium cetyl sulfate. Examples of derivatives of alkyl sulfate salts include sodium POE lauryl sulfate. Examples of sulfosuccinate esters include disodium lauryl sulfosuccinate. Examples of N-alkyloylmethyltaurine salts include sodium N-stearoyl-N-methyltaurine.

Among these anionic surfactants, it is preferable to contain an alkyl sulfate salt, since this improves the stability of the emulsion state. In addition, among these anionic surfactants, one type may be contained alone, or two or more types may be contained in combination.

Examples of cationic surfactants include lauryl trimethyl ammonium chloride, cetyl trimethyl ammonium chloride, stearyl trimethyl ammonium chloride, alkyl trimethyl ammonium chloride, distearyl dimethyl ammonium chloride, behenyl trimethyl aluminum chloride, distearyl dimethyl ammonium chloride, cetyl trimethyl ammonium bromide, stearyl trimethyl ammonium bromide, lanolin fatty acid aminopropyl ethyl dimethyl ammonium ethyl sulfate, stearyl trimethyl ammonium saccharin, cetyl trimethyl ammonium saccharin, methacryloyloxyethyl trimethyl ammonium chloride, behenyl trimethyl ammonium methyl sulfate, etc. Among these cationic surfactants, one type may be contained alone, or two or more types may be contained in combination.

Examples of amphoteric surfactants include cocobetaine, lauramidopropyl betaine, cocamidopropyl betaine, sodium lauroamphoacetate, sodium cocoamphoacetate, coconut oil fatty acid amidopropyl betaine, lauryl betaine, sodium laurylaminopropionate, etc. Among these amphoteric surfactants, one type may be contained alone, or two or more types may be contained in combination.

Examples of the water-soluble polymer include natural polymers, semi-synthetic polymers, synthetic polymers, and inorganic polymers.
Examples of natural polymers include starch, 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, and pullulan.

Examples of semi-synthetic polymers include crystalline cellulose, methyl cellulose, ethyl cellulose, hydroxyethyl cellulose, hydroxyethyl cellulose dimethyl diallyl ammonium chloride, hydroxypropyl cellulose, carboxymethyl cellulose, sodium carboxymethyl cellulose, hydroxypropyl methyl cellulose, cationic cellulose, cationic guar gum, starch phosphate ester, propylene glycol alginate ester, alginate salts, etc.

Examples of synthetic polymers include polyvinyl caprolactam, polyvinyl alcohol, polyvinyl pyrrolidone, vinyl pyrrolidone-vinyl acetate copolymer, polyvinyl butyral, polyvinyl methyl ether, carboxyvinyl polymer, sodium polyacrylate, polyacrylamide, polyethylene oxide, polyurethane, ethylene oxide-propylene oxide block copolymer, acrylic acid/alkyl acrylate copolymer, half ester of itaconic acid and POE alkyl ether, or copolymer of ester of methacrylic acid and POE alkyl ether and at least one monomer selected from acrylic acid, methacrylic acid, and their alkyl esters.

Among these water-soluble polymers, only one type may be contained alone, or two or more types may be contained in combination.
The pH adjuster can be blended to adjust the pH of the hair dye composition. Examples of the pH adjuster include salts of organic acids. Examples of the organic acid include hydroxy acids and dicarboxylic acids. Examples of the salt include sodium salts and ammonium salts. Of these pH adjusters, one type may be contained alone, or two or more types may be contained in combination.

Examples of the sugars include sorbitol, maltose, glycosyltrehalose, and N-acetylglucosamine. One of these sugars may be contained alone, or two or more of them may be contained in combination.

Examples of the preservatives include paraben, methylparaben, sodium benzoate, etc. Among these preservatives, one type may be contained alone, or two or more types may be contained in combination.

Examples of the chelating agent include ethylenediaminetetraacetate, diethylenetriaminepentaacetate, and hydroxyethanediphosphonate. Examples of the hydroxyethanediphosphonate include tetrasodium hydroxyethanediphosphonate, disodium hydroxyethanediphosphonate, and sodium hydroxyethanediphosphonate. Among these chelating agents, one type may be contained alone, or two or more types may be contained in combination.

Examples of the stabilizers include phenacetin, 8-hydroxyquinoline, acetanilide, sodium pyrophosphate, etc. Among these stabilizers, one type may be contained alone, or two or more types may be contained in combination.

The above amino acids include threonine, theanine, taurine, etc. Among these amino acids, one type may be contained alone, or two or more types may be contained in combination.

Examples of the inorganic salt include sodium chloride and sodium carbonate. One of these inorganic salts may be contained alone, or two or more of them may be contained in combination.

[Formulation of hair dye composition]
The formulation of the hair dye composition is not particularly limited, and examples thereof include liquid, emulsion (water-in-oil emulsion, oil-in-water emulsion, multiple emulsion), powder, tablet, gel, and foam. In the case of a foam formulation, the composition can be made into a foam using a known foaming tool. Examples of known foaming tools include non-aerosol type formers, aerosol type formers, and shakers. In the case of an aerosol type former, known propellants and foaming agents can be used. In the case of a solid formulation, a dispersant may be added to the hair dye composition.

[Uses of hair dye composition]
There is no particular limitation on the color the hair dye composition may be used to dye hair, but it can be suitably used to dye hair a darker color, particularly to dye hair a brown to black color.

The hair dye composition is preferably used for dyeing so-called gray hair, but may also be used to dye hair that has been bleached, or may be used to dye hair of any color.
The product form of the hair dye composition is not particularly limited, but the hair dye composition can be suitably used as a hair manicure, a color treatment, a color shampoo, and the like.

[Preparation of hair dye composition]
The hair dye compositions according to the respective Examples and Comparative Examples shown in Table 1 were each prepared as an emulsion composition in a conventional manner. The values showing the content of each component in Table 1 are in mass %.

[Evaluation of color stability]
Using the following procedure, hair strands were dyed using each prepared hair dye composition as is, and hair strands were dyed using each hair dye composition after storing it at 60°C for one week, and the color tones of the two were compared to evaluate the color stability after long-term storage.

First, a 10 cm long human gray hair bundle (manufactured by Bealux Co., Ltd.) was washed with Bigen Treatment Shampoo (manufactured by Hoyu Co., Ltd.). Next, 1 g of each hair dye composition and each hair dye composition stored in a polyethylene container at 60°C for one week were applied to the hair bundle with a brush, and the hair bundle was left to stand for 10 minutes at 30°C. Next, the hair dye composition was rinsed off with water, and the hair bundle was dried.

A hair strand dyed with each hair dye composition as is and a hair strand dyed with each hair dye composition after storage were visually observed by 10 expert panelists under a standard light source to evaluate whether or not changes in color tone were sufficiently suppressed. When hair is dyed with a hair dye composition containing (B) Black 401 after long-term storage, the color tone of the hair usually changes to a reddish tone. Therefore, each panelist evaluated the color stability by choosing between "good" and "not good", mainly based on whether changes to a reddish tone were suppressed.

If 8 or more out of 10 panelists answered that the color stability was "good," the evaluation was made on a 5-point scale: "very good: 5," if 6-7 panelists answered "good: 4," if 4-5 panelists answered "fair: 3," if 2-3 panelists answered "slightly poor: 2," and if 1 or less panelists answered "poor: 1." The evaluation results are shown in Table 1.

[Other evaluations]
Each hair dye composition was evaluated in terms of skin staining and color tone as follows. The evaluation results are shown in Table 2.

(Skin stains)
0.1 g of each hair dye composition was applied to the inner part of the subject's arm in a circular shape with a diameter of 1 cm, and left for 10 minutes, and then washed with water. Next, 10 expert panelists visually observed the inner part of the arm under a standard light source and rated the skin staining by selecting between "little" and "not quite little" with the usual evaluation sense of scalp staining in mind. If 8 or more panelists out of 10 answered that the skin staining was "little", the result was rated on a 5-point scale: "very good: 5", if 6-7 panelists answered "good: 4", if 4-5 panelists answered "fair: 3", if 2-3 panelists answered "slightly poor: 2", and if 1 or less panelists answered "poor: 1".

(Color Tone)
A 10 cm long human gray hair bundle (manufactured by Bealux Co., Ltd.) was washed with shampoo "Bigen Treatment Shampoo" (manufactured by Hoyu Co., Ltd.). Then, 1 g of each hair dye composition was applied to the hair bundle with a brush, and the hair bundle was left to stand for 10 minutes at 30° C. The hair dye composition was then washed off with water, and the hair bundle was dried.

A panel of experts visually inspected the hair bundles produced under a standard light source and rated them on a 5-point scale according to the target color tone, for example, whether it was purple to blue compared to black, using the following criteria.

5: Very good (not purple or blue, exactly as intended).
4: Good (slightly purple to blue, but on target color tone).
3: Fair (slightly more purple to blue than the target color tone, but within the acceptable range).
2: Fairly poor (purple to bluish).
1: Poor (strong purple to blue color).

[Table 1]

[Table 2]

[Discussion]
As shown in Examples 1 to 7, all of the acidic hair dye compositions containing (A) Purple 401, not containing (B) Black 401, and containing (C) an acid, were excellent in color stability. Furthermore, as shown in Example 8, even when (B) Black 401 was contained, the color stability was excellent when the mass ratio (A)/(B) was 15 or more.

On the other hand, as shown in Comparative Example 1, when the mass ratio (A)/(B) was less than 15, the color stability was not good. Also, as shown in Comparative Examples 2 to 5, when (B) Black 401 was contained but (A) Purple 401 was not contained, the color stability was not good, although the target color tone was as expected. Also, as shown in Comparative Example 6, even when (B) Black 401 was not contained, when (C) Acid was not contained, the color stability was not good. Note that in Comparative Example 6, the hair dyeing power of the hair dye composition was low and it was difficult to dye the hair strands, so it was difficult to evaluate whether the target color tone was as expected.

Furthermore, when Examples 1 to 7 are compared, the color stability was superior in the case where levulinic acid was contained compared to the case where other acids were contained.
Furthermore, the hair dye compositions containing the component (D) according to Examples 1 and 3 to 8 suppressed scalp staining more than the hair dye composition not containing the component (D) according to Example 2.

In addition, the hair dye compositions according to Examples 1, 2, and 5 to 8, in which the mass ratio (A)/(C) was in the range of 0.01 or more and 0.2 or less, had a more suppressed purple to blue color due to (A) Purple 401 than the hair dye compositions according to Examples 3 to 5, in which the mass ratio (A)/(C) was not in the range of 0.01 or more and 0.2 or less.

Claims (3)

An acidic hair dye composition comprising:
(A) containing Violet 401,
The acidic hair dye composition does not contain (B) Black 401, or contains (B) Black 401 and has a mass ratio (A)/(B) of the content of (A) Purple 401 in the acidic hair dye composition to the content of (B) Black 401 in the acidic hair dye composition of 15 or more;
(C) containing an acid ,
The acid (C) contains at least levulinic acid among levulinic acid, succinic acid, phosphoric acid, and pyrrolidone carboxylic acid,
An acidic hair dye composition, wherein the mass ratio (A)/(C) of the content of (A) Purple 401 in the acidic hair dye composition to the content of (C) acid in the acidic hair dye composition is 0.01 or more and 0.2 or less . The acidic hair dye composition according to claim 1, further comprising (D) at least one selected from the group consisting of HC Yellow 2, HC Yellow 4, HC Orange 1, HC Red 1, HC Red 3, 4-amino-3-nitrophenol, 3-nitro-p-hydroxyethylaminophenol, 2-hydroxyethylpicramic acid, hydroxyethyl-2-nitro-p-toluidine, 2 -amino-6-chloro-4-nitrophenol, and 4-hydroxypropylamino-3-nitrophenol. 3. The acidic hair dye composition according to claim 2, wherein the mass ratio (D)/(A) of the content of the (D) component in the hair dye composition to the content of the (A) Purple 401 in the hair dye composition is 0.2 or more.