Hair treatment

Abstract

To provide hair treatment agents capable of suppressing the deterioration of hair strength (firmness, stiffness, difficulty of cutting, combability) due to hair dyeing and bleaching treatments, and at the same time, suppressing generation of an unpleasant hair odor caused by these hair treatments.SOLUTION: Provided is a hair treatment agent containing a carboxylic acid or a salt thereof and an alkaline agent, the carboxylic acid being at least one of tartaric acid and malic acid, and the content of carboxylic acid or a salt thereof being 0.001 to 30 mass%.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a hair treatment agent used in hair treatments such as dyeing treatment and bleaching treatment.

Background Art

[0002] Hair deformation treatments such as hair dyeing treatment, bleaching treatment, permanent wave treatment, and hair straightening treatment can change the hair to a desired lightness and color tone, while reducing the gloss and cohesion of the hair and causing various damages to the hair.

[0003] Therefore, hair treatment agents for reducing these damages to the hair have been proposed. More specifically, an oxidative hair dye containing an alkaline agent containing a carbonate and a specific alkaline chelating agent such as ethylenediaminetetraacetic acid (EDTA) has been proposed, and it is described that by using such an oxidative hair dye, there is less pungent odor, low irritation, good lightness can be imparted to the hair, and sufficient hair dyeing power can also be ensured (see, for example, Patent Document 1).

[0004] In addition, a hair bleaching agent and an oxidative hair dye containing an alkaline agent, an oily component, a surfactant, an oxidizing agent, and a chelating agent, wherein the chelating agent contains at least one kind of gluconic acid or its salt and the blending amount is 0.002 to less than 0.2% by mass have been proposed. And it is described that by using such a hair bleaching agent and an oxidative hair dye, good emulsion stability, bleaching power, hair dyeing power, and texture can be achieved, and irritation during the treatment and damage to the hair can be sufficiently reduced (see, for example, Patent Document 2).

Prior Art Documents

Patent Documents

[0005]

Patent Document 1

Patent Document 2

Summary of the Invention

[0006] However, in the oxidative hair dyes described in Patent Documents 1 and 2 above, while the chelating agents mentioned above improve dyeing and bleaching power and reduce irritation and damage to the hair during treatment, these chelating agents have the problem of reducing the strength of the hair (firmness, resilience, resistance to breakage, combability) due to dyeing treatments.

[0007] Therefore, the present invention has been made in view of the above problems, and aims to provide a hair treatment agent that can suppress the decrease in hair strength (firmness, resilience, resistance to breakage, combability) caused by dyeing and bleaching treatments, while simultaneously suppressing the generation of unpleasant odors in the hair caused by these hair treatments. [Means for solving the problem]

[0008] To achieve the above objective, the present invention provides a hair treatment agent containing a carboxylic acid or a salt thereof and an alkaline agent, wherein the carboxylic acid is at least one of tartaric acid and malic acid, and the content of the carboxylic acid or a salt thereof is 0.001 to 30% by mass. [Effects of the Invention]

[0009] According to the present invention, it is possible to suppress the decrease in hair strength (firmness, resilience, resistance to breakage, and combability) caused by dyeing or bleaching treatments, while simultaneously suppressing the generation of unpleasant odors in the hair caused by these hair treatments. [Modes for carrying out the invention]

[0010] Preferred embodiments of the present invention are described below. However, the present invention is not limited to the embodiments described below, and can be modified and applied as appropriate without altering the essence of the invention.

[0011] The hair treatment agent of the present invention is used as an oxidative hair dye or bleaching agent and contains a carboxylic acid or a salt thereof and an alkaline agent.

[0012] (Carboxylic acids or their salts) As the carboxylic acid or its salt, at least one of tartaric acid and malic acid carboxylic acids or a salt thereof is used.

[0013] These carboxylic acids or their salts have a high reactivity with the amino groups of keratin fibers, allowing them to penetrate into the hair shaft and form an elastic core, thereby suppressing the decrease in strength (firmness, resilience, and combability) caused by dyeing and bleaching treatments.

[0014] Furthermore, these carboxylic acids or their salts specifically adsorb to irritating sulfur oxide compounds derived from the oxidation of proteins, which are components of hair, or amino acids, which are their constituent units, as by-products of the oxidation reaction of oxidative hair dyes or bleaching agents. This suppresses their generation, thus preventing the generation of unpleasant odors in hair caused by dyeing or bleaching treatments.

[0015] Furthermore, in the present invention, the amount of carboxylic acid or its salts in relation to the total amount of the hair treatment agent is 0.001 to 30% by mass, and preferably 0.1 to 5% by mass.

[0016] This is because if the amount of carboxylic acid or its salts is less than 0.001% by mass, the aforementioned decrease in strength may not be sufficiently suppressed, and if it is greater than 30% by mass, excessive adsorption to the hair and a strong astringent effect in some areas may occur, causing changes in the three-dimensional structure of the hair and potentially reducing its strength. In particular, if it is greater than 30% by mass, the high concentration leads to a decrease in the viscosity of the formulation and a decrease in the stability of the emulsification, resulting in non-uniformity of the formulation during use. This significantly reduces the dyeing and bleaching power, and may also cause reaction odors during dyeing and bleaching treatments, as well as residual odors (unpleasant odors) after hair treatment.

[0017] (Alkaline agent) As the alkali agent, ammonia, monoethanolamine, diethanolamine, and aminomethylpropanol (AMP) are used.

[0018] These alkali agents are for activating an oxidizing agent (e.g., hydrogen peroxide) to improve the dyeing power and decoloring power. More specifically, in hair dyeing with an oxidative hair dye, the activated oxidizing agent decomposes melanin pigments derived from hair, so that hair decoloration progresses. At the same time, oxidative polymerization of an oxidative dye (dye intermediate and coupler) progresses to form a pigment, and hair coloring by the pigment progresses. When hair decoloration and coloring with an oxidative hair dye proceed simultaneously, the dyeing power and decoloring power are improved by these alkali agents.

[0019] Among these, from the viewpoint of having a relatively small remaining amount on the hair after treatment and reducing damage to the hair that occurs after the treatment, it is preferable to use ammonia (strong aqueous ammonia), which is a volatile alkali agent.

[0020] In addition, in the present invention, from the viewpoint of reliably suppressing a decrease in the dyeing power by the hair dyeing treatment and the decoloring power by the decoloring treatment, the blending amount of the alkali agent with respect to the entire hair treatment agent is preferably 0.3 to 26.7% by mass, and more preferably 3.0 to 9.7% by mass.

[0021] (pH buffer) In addition, from the viewpoint of alleviating the increase in pH caused by the above-mentioned alkali agent and suppressing a decrease in the decoloring power and dyeing power, the hair treatment agent of the present invention may contain a pH buffer. As this pH buffer, carbonates such as ammonium hydrogen carbonate, ammonium carbonate, sodium hydrogen carbonate, sodium carbonate, potassium hydrogen carbonate, and potassium carbonate are preferable.

[0022] The blending amount of the pH buffer with respect to the entire hair treatment agent is not particularly limited, but is preferably 0.01 to 10% by mass.

[0023] (Phosphate ester) In addition, the hair treatment agent of the present invention may contain a phosphate ester. By containing a phosphate ester which is an anionic surfactant, it is possible to reliably suppress a decrease in the strength of hair and to reliably improve the dyeing power by a hair dyeing treatment and the decoloring power by a decoloring treatment.

[0024] As this phosphate ester, for example, at least one selected from the group consisting of polyoxyethylene alkyl ether phosphoric acid, salts of polyoxyethylene alkyl ether phosphoric acid, and alkyl phosphoric acid is used.

[0025] Examples of polyoxyethylene alkyl ether phosphoric acid or its salts include POE oleyl ether phosphoric acid, sodium POE oleyl ether phosphate, POE lauryl ether phosphoric acid, sodium POE lauryl ether phosphate, POE cetyl ether phosphoric acid, sodium POE cetyl ether phosphate, POE stearyl ether phosphoric acid, sodium POE stearyl ether phosphate, sodium di-POE lauryl ether phosphate, sodium dioleyl POE ether phosphate, di-POE(C12-15) alkyl ether phosphoric acid, tri-POE lauryl ether phosphoric acid, tri-POE cetyl ether phosphoric acid, tri-POE(C12-15) alkyl ether phosphoric acid and other POE alkyl ether phosphoric acids or their salts. Examples of alkyl phosphoric acid include cetyl phosphate, dicetyl phosphate, trioleyl phosphate, tristearyl phosphate and the like.

[0026] In addition, in the present invention, the blending amount of the phosphate ester with respect to the whole hair treatment agent is not particularly limited, but it is preferably 0.1 to 10% by mass.

[0027] (pH) The pH of the hair treatment agent of the present invention is set to 8.5 to 11.5 by the above pH buffer. For example, when used as an oxidative hair dye or a decoloring agent, the pH is set to 8.5 to 11.5.

[0028] (Solvent) Furthermore, the solvent (dispersion medium) used in the hair treatment agent of the present invention is not particularly limited, and water (purified water, etc.) is used, but if necessary, organic solvents such as ethanol and isopropanol may be included in the water at a concentration that is harmless even if it comes into contact with the human body.

[0029] Furthermore, the embodiment of the hair treatment agent of the present invention is not limited to a solution, and the added components may be suspended or emulsified as needed.

[0030] (Other ingredients) The hair treatment agent of the present invention may contain other components, to the extent that it does not impair the effects of the present invention, such as pH adjusting components (e.g., citric acid, lactic acid, phosphoric acid, etc.), oily components (e.g., sphingolipids, ceramides, cholesterol derivatives, phytosterol derivatives, phospholipids, lanolin fatty acid derivatives, perfluoropolyethers, etc.), vegetable oils (e.g., olive oil, shea butter, macadamia nut oil, etc.), waxes (e.g., jojoba seed oil, carnauba wax, candelilla wax, beeswax, etc.), and hydrocarbons (e.g., light liquid isoparaffin, paraffin, squalane, petrolatum, isodone). (e.g., decane, isohexadecane), higher fatty acids (e.g., myristic acid, oleic acid, stearic acid, isostearic acid, branched fatty acids (C14-28), hydroxystearic acid, etc.), alcohols (e.g., cetanol, isostearyl alcohol, oleyl alcohol, hydrogenated rapeseed alcohol, cholesterol, sitosterol, 1,3-butylene glycol, propylene glycol, dipropylene glycol, glycerin, diglycerin, 1,2-hexanediol, etc.), sugars and their derivatives (e.g., glucose, sucrose, D-sorbitol) (e.g., maltose, trehalose, polyoxypropylene methyl glucoside, glyceryl glucoside, etc.), esters (e.g., isopropyl myristate, cetyl palmitate, ethylhexyl palmitate, octyldodecyl oleate, glyceryl triisostearate, diethoxyethyl succinate, cetyl lactate, octyldodecyl lanolinate, etc.), silicones (e.g., dimethyl silicone, methylphenyl silicone, cyclic dimethyl silicone, polyether-modified silicone, alkyl-modified silicone, amino-modified silicone, dimethicone) (e.g., PCA dimethicone), amino acids and their derivatives (e.g., glutamic acid, aspartic acid, glycine, serine, methionine, trimethylglycine, sodium polyaspartate, sodium dilauroyl glutamate lysine, N-lauroyl-L-lysine, etc.), PPT and proteins (e.g., hydrolyzed silk, hydrolyzed wheat, hydrolyzed soy, hydrolyzed collagen, hydrolyzed keratin, silylated hydrolyzed silk, silylated hydrolyzed wheat, cationized hydrolyzed silk, cationized hydrolyzed collagen, keratin, etc.), natural polymers (e.g.,Alginates, mannan, acacia gum, tamarind gum, chitosan, carrageenan, mucin, shellac, hyaluronic acid, cationized hyaluronic acid, xanthan gum, dextrin, hydroxyethylcellulose, cationized cellulose, guar gum, cationized guar gum, honey, etc.), synthetic polymers (e.g., anionic polymers, cationic polymers, nonionic polymers, amphoteric polymers, polyethylene glycol, polypropylene glycol, polyoxypropylene diglyceryl ether, etc.), other anionic surfactants (e.g., alkyl ethercalcium (e.g., sodium phosphate, N-acyl glutamic acid, N-acyl methyl taurate salt, alkyl sulfosuccinate, alkyl ether sulfates such as sodium lauryl sulfate, etc.), other cationic surfactants (e.g., alkylamine salts, fatty acid amidoamine salts, etc.), amphoteric surfactants (e.g., glycine-type amphoteric surfactants, aminopropionic acid-type amphoteric surfactants, aminoacetic acid betaine-type amphoteric surfactants, sulfobetaine-type amphoteric surfactants, etc.), nonionic surfactants (e.g., polyoxyethylene cetyl ether and polyoxyethylene lauryl ether, etc.) (Tylene alkyl ethers, polyoxyethylene sorbitan fatty acid esters, polyoxyethylene hydrogenated castor oil, alkyl glucosides, new oil-type glyceryl monostearate, etc.), dyes (e.g., tar dyes, natural dyes, etc.), plant extracts (e.g., chamomile extract, comfrey extract, sage extract, rosemary extract, persimmon tannin, tea distillate, copper chlorophyllin sodium, etc.), vitamins (e.g., L-ascorbic acid, DL-α-tocopherol, D-panthenol, natural vitamin E, etc.), UV absorbers (e.g., para-aminobenzoic acid, salicylic acid) Octyl acid, 2-ethylhexyl paramethoxycinnamate, ferulic acid, etc.), preservatives other than those listed above (e.g., benzoic acid, sodium benzoate, salicylic acid, dehydroacetic acid, sodium dehydroacetate, parabens, phenoxyethanol, etc.), antioxidants (e.g., sodium bisulfite, dibutylhydroxytoluene, etc.), chelating agents other than those listed above (e.g., edetates, sodium polyphosphate, phytic acid, etc.), other inorganic compounds (e.g., titanium dioxide, silver, platinum, iron chloride, iron oxide, sodium bromate, hydrogen peroxide, etc.), other organic compounds (e.g., urea,Known cosmetic ingredients such as hydroxyethyl urea, dl-pyrrolidone carboxylate sodium, copper gluconate, etc., solvents (e.g., benzyl alcohol, etc.), propellants (e.g., LPG (liquefied petroleum gas), DME (dimethyl ether), nitrogen gas, carbon dioxide, etc.), and fragrances can be incorporated.

[0031] The hair modification treatment agent of the present invention can be prepared in the form of liquid, milk, cream, foam (form during use), mist (form during use), etc., by known methods, and can also be prepared in aerosol form. [Examples]

[0032] The present invention will be described below based on examples. However, the present invention is not limited to these examples, and these examples can be modified or altered in accordance with the spirit of the invention; such modifications do not exclude them from the scope of the invention.

[0033] (Examples 1-90 and Comparative Examples 1-18) <Manufacturing of hair treatment agents> By mixing water (purified water) with each raw material, hair treatment agents for Examples 1-90 and Comparative Examples 1-18, having the compositions (mass%) shown in Tables 1-10, were manufactured.

[0034] <Hair dye: Preparation of the second agent> In addition to the hair treatment agents of the present invention, an aqueous hydrogen peroxide solution (hydrogen peroxide concentration: 5.8% by mass) adjusted to pH 3.0 with phosphoric acid was prepared as a second agent to be combined with each of the hair treatment agents in the examples and comparative examples.

[0035] [Table 1]

[0036] [Table 2]

[0037] [Table 3]

[0038] [Table 4]

[0039] [Table 5]

[0040] [Table 6]

[0041] [Table 7]

[0042] [Table 8]

[0043] [Table 9]

[0044] [Table 10]

[0045] <Preparing hair for samples> A hair bundle (5g) consisting of 30cm long straight hair was used. This bundle underwent two chemical treatments using commercially available hair dye, followed by a permanent wave treatment using commercially available perming solution. The treated hair was then immersed overnight in a 5% by mass aqueous solution of polyoxyethylene lauryl sulfate at 50°C, and thoroughly rinsed with water to obtain the sample hair.

[0046] <Decolorization treatment (Examples 1-22, 45-47, 51-61, 73-78, 85-87, Comparative Examples 1-8, 17)> Next, the prepared hair underwent the following bleaching treatments (A) to (C).

[0047] (A) First, 10 g of the hair treatment agent of the present invention and 10 g of the second agent were prepared for 5 g of sample hair, and the hair treatment agent and the second agent were mixed to prepare a bleaching agent.

[0048] (B) Next, the prepared bleaching agent was applied evenly to the entire hair and left for 25 minutes.

[0049] (C) After a 25-minute bleaching treatment, the bleaching agent was rinsed off, shampoo and conditioner were applied, and then the hair was dried using a hairdryer.

[0050] <Staining treatment (Examples 23-44, 48-50, 62-72, 79-84, 88-90, Comparative Examples 9-16, 18)> Next, the prepared hair underwent the following dyeing treatments (D) to (F).

[0051] (D) First, 10 g of the hair treatment agent of the present invention and 10 g of the second agent were prepared for 5 g of sample hair, and the hair treatment agent and the second agent were mixed to prepare an oxidative hair dye.

[0052] (E) Next, the prepared oxidative hair dye was applied evenly to the entire hair and left for 25 minutes.

[0053] (F) After a 25-minute dyeing treatment, the oxidative hair dye was rinsed off, the hair was shampooed and conditioned, and then the hair was dried using a hairdryer.

[0054] <Evaluation of bleaching power> A sensory evaluation was conducted on the effect of the aforementioned hair treatment agent on the finished appearance of hair that had undergone the aforementioned bleaching treatment. Specifically, the evaluation was conducted by 10 expert panelists based on the following evaluation criteria. Excellent bleaching power: ◎ Has bleaching power: ○ Slightly weak bleaching power: △ No bleaching power: ×

[0055] <Dye strength evaluation> A sensory evaluation was conducted on the effect of the aforementioned hair treatment agent on the finished appearance of the dyed hair, which had undergone the aforementioned dyeing treatment. Specifically, the evaluation was conducted by 10 expert panelists based on the following evaluation criteria. Excellent dyeing power: ◎ Has dyeing power: ○ Poor dyeing power: △ Poor dyeing ability: ×

[0056] <Evaluation of irritating odor when mixed> A sensory evaluation was conducted to assess the effect of the aforementioned hair treatment agent on the irritating odor generated during the preparation process of the aforementioned bleaching agent or oxidative hair dye (the irritating odor generated when mixed with the second agent). Specifically, the evaluation was conducted by 10 expert panelists according to the evaluation criteria below. Almost no pungent odor: ◎ Slightly noticeable pungent odor: ○ I can smell a strong odor: △ I strongly detect a strong odor: ×

[0057] <Evaluation regarding the finished product> Next, a sensory evaluation was conducted on the effect of the hair treatment agents described above on the finished feel after drying following the bleaching or dyeing treatment of the hair. Specifically, the evaluation was conducted by 10 expert panelists on three items: (1) combability, (2) resistance to breakage, and (3) firmness and body. The evaluation criteria for each evaluation item are shown below.

[0058] (1) Combing The combability (smoothness) of hair strands that had been dried after the final rinse following bleaching or dyeing treatment was evaluated according to the following evaluation criteria. Very easy to comb: ◎ Hair goes through easily: ○ Combing is slightly difficult: △ Hair is difficult to comb: ×

[0059] (2) Resistance to breakage The resistance to breakage in the dry state after decolorization or dyeing was evaluated according to the following evaluation criteria. When a certain amount of hair was pulled, it did not stretch easily and did not break: ◎ When a certain amount of hair was pulled, it stretched out completely but did not break: ○ When a certain amount of hair was pulled, it stretched out completely and then broke: △ When a certain amount of hair was pulled, it broke immediately: ×

[0060] (3) Firmness and resilience The firmness and body of the fabric in its dry state after decolorization or dyeing were evaluated according to the following evaluation criteria. Excellent firmness and body: ◎ Has firmness and body: ○ Lacks firmness and body: △ Lack of firmness and body: ×

[0061] <Evaluation regarding residual odor> After the final rinse following the bleaching or dyeing treatment, the dried hair bundles were loosened, and the presence or absence of residual odor was evaluated according to the following evaluation criteria. No lingering odor: ◎ Almost no lingering odor: ○ Slight lingering odor: △ Strong lingering odor: ×

[0062] In the above evaluations, "◎" indicates exceptionally good, and "○" indicates good. "△" and "×" indicate insufficient. The results are shown in Tables 1 to 10.

[0063] As shown in Table 1, the hair treatment agents of Examples 1 to 8, which contain at least one of tartaric acid and malic acid or a salt thereof, can suppress the decrease in strength (firmness, resilience, combability) due to bleaching treatment, and can also suppress the generation of unpleasant odors in the hair caused by bleaching treatment, compared to Comparative Examples 1 to 7, which contain other acids such as succinic acid.

[0064] Furthermore, as shown in Tables 1-2, the hair treatment agents of Examples 1-22, which contain 0.001-30% by mass of at least one of tartaric acid and malic acid or a salt thereof, can suppress the decrease in strength (firmness, resilience, and combability) caused by bleaching, and can also suppress the generation of unpleasant odors in the hair caused by bleaching.

[0065] In particular, the hair treatment agents of Examples 1-8, 11-13, and 17-20, which contain 0.1-5% by mass of at least one of tartaric acid and malic acid or a salt thereof, can reliably suppress the decrease in strength (firmness, resilience, and combability) caused by bleaching, and can also reliably suppress the generation of unpleasant odors in the hair caused by bleaching.

[0066] On the other hand, in Comparative Example 8, which contains 40% by mass of sodium tartrate, it was found that the strength decreased, the bleaching power decreased significantly, and an unpleasant odor of hair was generated due to the bleaching treatment.

[0067] Furthermore, as shown in Table 3, the hair treatment agents of Examples 23 to 30, which contain at least one of tartaric acid and malic acid or a salt thereof, can suppress the decrease in strength (firmness, resilience, combability) caused by dyeing treatment, and can also suppress the generation of unpleasant odors in the hair caused by dyeing treatment, compared to Comparative Examples 9 to 15, which contain other acids such as succinic acid.

[0068] Furthermore, as shown in Tables 3-4, the hair treatment agents of Examples 23-44, which contain 0.001-30% by mass of at least one of tartaric acid and malic acid or a salt thereof, can suppress the decrease in strength (firmness, resilience, and combability) caused by dyeing treatment, and can also suppress the generation of unpleasant odors in the hair caused by dyeing treatment.

[0069] In particular, the hair treatment agents of Examples 23-30, 33-35, and 39-42, which contain 0.1-5% by mass of at least one of tartaric acid and malic acid or a salt thereof, can be reliably suppressed to reduce the strength (firmness, resilience, and combability) caused by dyeing treatment, and can also be reliably suppressed to suppress the generation of unpleasant odors in the hair caused by dyeing treatment.

[0070] On the other hand, in Comparative Example 16, which contains 40% by mass of sodium tartrate, it was found that the strength decreased, the dyeing power decreased significantly, and an unpleasant odor in the hair was generated due to the dyeing process.

[0071] Furthermore, as shown in Tables 1 to 5, the hair treatment agents of Examples 1 to 50, which contain at least one of tartaric acid and malic acid or a salt thereof, and also contain ammonia, monoethanolamine, diethanolamine, and aminomethylpropanol as alkaline agents, can suppress the decrease in decolorization power (or dyeing power) due to decolorization treatment compared to Comparative Examples 17 to 20, which contain other alkaline agents such as sodium hydride.

[0072] Furthermore, as shown in Table 6, the hair treatment agents of Examples 51 to 61, which contain 0.3 to 26.7% by mass of alkaline agent, can suppress the decrease in strength (firmness, resilience, and combability) caused by bleaching, and can also suppress the generation of unpleasant odors in the hair caused by bleaching.

[0073] Furthermore, as shown in Table 7, the hair treatment agents of Examples 62 to 72, which contain 0.3 to 26.7% by mass of alkaline agent, can suppress the decrease in strength (firmness, resilience, and combability) caused by dyeing treatment, and can also suppress the generation of unpleasant odors in the hair caused by dyeing treatment.

[0074] Furthermore, as shown in Table 8, it can be seen that in Examples 73-77, which contain carbonate as a pH buffer, the decrease in decolorization power due to the decolorization treatment can be effectively suppressed.

[0075] Furthermore, as shown in Table 9, it can be seen that in Examples 79-83, which contain carbonate as a pH buffer, the decrease in dyeing strength due to the dyeing treatment can be effectively suppressed.

[0076] Furthermore, as shown in Table 10, it can be seen that the same effects as in the other examples can be obtained in Examples 85 to 90, which contain polyoxyethylene stearyl ether phosphate, polyoxyethylene alkyl (12-15) ether phosphate, and dicetyl phosphate as phosphate esters other than polyoxyethylene cetyl ether phosphate. [Industrial applicability]

[0077] As described above, the present invention is particularly useful as a hair treatment agent used in hair treatments such as dyeing and bleaching.

Claims

1. A hair treatment agent used in combination with a second agent containing hydrogen peroxide, containing a carboxylic acid or its salt and an alkaline agent, The carboxylic acid is tartaric acid, The content of the carboxylic acid or its salt is 0.001 to 5% by mass. The alkaline agent is at least one selected from the group consisting of ammonia, diethanolamine, and aminomethylpropanol. It further contains a pH buffering agent, The pH buffer is a carbonate selected from the group consisting of ammonium bicarbonate, ammonium carbonate, sodium bicarbonate, sodium carbonate, potassium bicarbonate, and potassium carbonate. It further contains phosphate esters, The phosphate ester is at least one selected from the group consisting of POE oleyl ether phosphate, POE oleyl ether sodium phosphate, POE cetyl ether phosphate, POE cetyl ether sodium phosphate, POE stearyl ether phosphate, POE stearyl ether sodium phosphate, diPOE lauryl ether sodium phosphate, dioleyl POE ether sodium phosphate, diPOE (C12-15) alkyl ether phosphate, triPOE cetyl ether phosphate, triPOE (C12-15) alkyl ether phosphate, cetyl phosphate, dicetyl phosphate, trioleyl phosphate, and tristearyl phosphate. A hair treatment agent characterized by having a pH of 8.5 to 11.

5.

2. The hair treatment agent according to claim 1, characterized in that the content of the alkaline agent is 0.3 to 26.7% by mass.

3. The hair treatment agent according to claim 1 or 2, characterized in that the content of the carboxylic acid or its salt is 0.1 to 5% by mass.

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