Hair-deforming cosmetic composition

Abstract

To provide a hair-deforming cosmetic composition exhibiting low hair damage and having either a curling effect or a hair-straightening effect.SOLUTION: A hair-deforming cosmetic composition comprises thioglycolic acid, cysteamine, and an organic acid having a pKa value higher than that of thioglycolic acid, and its pH is adjusted to 8.0 or lower with a basic amino acid.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a hair transforming cosmetic composition that causes less damage to hair and has a curling or straightening effect. [Background technology]

[0002] A typical permanent wave creates curls by using a reducing agent and an oxidizing agent as its main ingredients. Specifically, a first agent containing a reducing agent such as thioglycolic acid or its salt, or cysteamine or its salt, is applied to hair wound around a rod to reduce and cleave the disulfide bonds present in the keratin protein. After intermediate rinsing with water, the hair is treated with a second agent containing an oxidizing agent such as hydrogen peroxide or sodium bromate as its main ingredient to oxidize and reform the disulfide groups, setting the curl in place.

[0003] A typical heat-type permanent wave creates curls by using a reducing agent, an oxidizing agent, or a high-temperature treatment. Specifically, a first agent containing a reducing agent, such as thioglycolic acid or its salt, or cysteamine or its salt, is applied to the hair to reduce and cleave the disulfide bonds present in the keratin protein. The hair is then washed with water, wrapped around a heating rod, and curled at 60°C to 120°C. The hair is then treated with a second agent, primarily containing an oxidizing agent, such as hydrogen peroxide or sodium bromate, either before or after the heating rod is removed to oxidize and reform the disulfide groups, thereby setting the curl. Alternatively, the hair may be curled using a high-temperature hair styling iron instead of a heating rod, and then treated with a second agent primarily containing an oxidizing agent, such as hydrogen peroxide or sodium bromate, to oxidize and reform the disulfide groups, thereby setting the curl.

[0004] Typical hair straightening treatments use reducing and oxidizing agents as the main ingredients, as well as high-temperature mechanical treatment to straighten curls. Specifically, a first agent containing a reducing agent such as thioglycolic acid or its salts, or cysteamine or its salts, is applied to the hair to reduce and cleave the disulfide bonds present in the keratin protein. The hair is then washed with water, dried with a hair dryer, or similar, and straightened by mechanical treatment with an iron at approximately 180°C. The hair is then treated with a second agent primarily containing an oxidizing agent such as hydrogen peroxide or sodium bromate to oxidize and reform the disulfide groups, leaving the hair in a straightened state.

[0005] In recent years, hair designs that lighten hair using hair color, bleach, or lightener have become widespread. These hair designs are accompanied by hair damage. When general permanent wave agents, heat-type permanent wave agents, and hair straighteners are used to form curls or straighten hair, the hair is damaged. Therefore, there is a demand for permanent wave agents, heat-type permanent wave agents, and hair straighteners that cause less damage to hair.

[0006] Patent Document 1 discloses an alkali-free perm composition that uses a cysteamine base and controls hair damage during perming by eliminating the addition of an alkali agent. However, it is unable to avoid swelling that occurs during hair treatment, and therefore the problem of hair damage caused by swelling remains unresolved. Patent Document 2 discloses a hair transformation treatment agent and a hair transformation treatment method that maintain hair transformation and improve the feel of hair while suppressing a decrease in hair strength. However, there is a problem that swelling that occurs during the hair treatment process cannot be avoided, and therefore hair damage due to swelling cannot be solved. Patent Document 3 discloses a hair transformation method that causes little damage to hair, does not impair or improves the firmness of hair, and can efficiently transform hair semi-permanently or permanently. However, there is a problem in that the effect of transforming hair shape is insufficient. Patent Document 4 discloses a first agent for hair transformation treatment that causes less hair damage due to swelling during the hair treatment process, has an excellent effect of transforming damaged hair into a different shape, and does not leave stiffness in the treated hair. However, there is a problem in that the effect of transforming hair into a different shape is insufficient. [Prior art documents]

[0007] [Patent Document 1] Patent No. 6074866 [Patent Document 2] Patent No. 6755601 [Patent Document 3] Japanese Patent Application Publication No. 2019-6769 [Patent Document 4] Patent No. 7166033 Summary of the Invention [Problem to be solved by the invention]

[0008] The present invention has been made in consideration of the drawbacks of the prior art, and aims to provide a hair transforming cosmetic product that causes less damage to hair and has a curling or hair straightening effect. The hair transforming cosmetic product in this specification refers to a first permanent wave agent, a first heated permanent wave agent, and a first hair straightening agent. The curling effect, which is the function of permanent wave agents and heated permanent wave agents, has a broad meaning that includes transforming hair into curls, waves, etc. The hair straightening function of hair straightening agents has a broad meaning that includes correcting, straightening, or making neat curly hair, wavy hair, frizzy hair, age-related wave or frizz, and dryness or frizz due to damage. [Means for solving the problem]

[0009] As a result of extensive research to solve the above-mentioned problems, the inventors discovered that a hair-transforming cosmetic product containing thioglycolic acid, cysteamine, and an organic acid with a higher pKa value than thioglycolic acid, and having a pH adjusted to 8.0 or less with a basic amino acid, can achieve a curling effect or hair straightening effect with less damage to hair, and thus completed the present invention. [Effects of the Invention]

[0010] The hair transforming cosmetic composition of the present invention makes it possible to form curls or straighten hair with less damage to the hair. DETAILED DESCRIPTION OF THE INVENTION

[0011] The hair transforming cosmetic composition of the present invention contains thioglycolic acid, cysteamine, and an organic acid with a higher pKa value than thioglycolic acid, and the pH is adjusted to 8.0 or less with a basic amino acid. The term "heated permanent wave" includes curl formation using a heating rod and curl formation using a high-temperature hair styling iron. Furthermore, the terms "perm wave agent," "heated permanent wave agent," and "hair straightener" have a broad meaning and include wash-off hair setting agents, such as curling agents, heated curling agents, and straightening agents, which are classified as cosmetics. The present invention will be described in detail below.

[0012] The content of thioglycolic acid may be, for example, 0.5% by mass or more relative to the total mass of the hair transforming cosmetic.

[0013] The cysteamine content may be, for example, 0.5% by mass or more relative to the total mass of the hair transforming cosmetic.

[0014] The total content of thioglycolic acid and cysteamine should be, for example, 1.5% by mass or more relative to the total mass of the hair transforming cosmetic product. If the content is less than 1.5% by mass, the action time will be too long to achieve sufficient curling and straightening effects.

[0015] The organic acid must have a pKa value higher than that of thioglycolic acid. If the pKa value of the organic acid is equal to or lower than that of thioglycolic acid, sufficient curling and straightening effects cannot be obtained. The content of the organic acid having a pKa value higher than that of thioglycolic acid is a content that neutralizes 80% or more of the cysteamine content. If the content neutralizes less than 80% of the cysteamine content, sufficient curling and straightening effects cannot be obtained. Examples of organic acids having a pKa value higher than that of thioglycolic acid include lactic acid, glycolic acid, succinic acid, and levulinic acid. One or more of these organic acids having a pKa value higher than that of thioglycolic acid may be used alone or in combination. The content that neutralizes 80% or more of the cysteamine content is determined by converting the contents of cysteamine and the organic acid having a pKa value higher than that of thioglycolic acid into mol / L and further converting the valence of the organic acid having a pKa value higher than that of thioglycolic acid.

[0016] The pH may be 8.0 or less, preferably 7.5 or less, and more preferably 7.0 or less. Alternatively, the pH may be 5.0 or more, preferably 5.5 or more, and more preferably 6.0 or more. If the pH is less than 5.0, the action time will be too long to achieve sufficient curling and straightening effects. If the pH is greater than 8.0, hair damage will occur. Examples of basic amino acids that adjust the pH include arginine, histidine, and lysine. One selected from these basic amino acids may be used alone, or two or more may be used in combination.

[0017] In addition to the above-mentioned components, the hair transforming cosmetic composition of the present invention can contain other commonly used components as desired, provided that the effects of the present invention are not impaired. Such components may include, for example, cationic polymers, anionic polymers, nonionic polymers, amphoteric polymers, polyhydric alcohols, sugars, amino acids, peptides, proteins, silicone oils, vitamins, oils, anionic surfactants, cationic surfactants, nonionic surfactants, amphoteric surfactants, tertiary amine compounds, fluorine compounds, diammonium aminoethylthiosuccinate, sulfites, bisulfites, sequestering agents, antioxidants, thickeners, gelling agents, anti-inflammatory agents, UV absorbers, plant extracts, solvents, preservatives, fragrances, powdered components, pigments, and water.

[0018] The formulation of the hair transforming cosmetic of the present invention is not particularly limited as long as it satisfactorily exerts the desired effect, but it can take the form of, for example, a liquid, emulsion, foam, gel, cream, or the like. [Example]

[0019] The present invention will be described in more detail below with reference to specific examples, but the present invention is not limited to the following examples. Furthermore, blending amounts in the following examples are expressed in mass % unless otherwise specified.

[0020] (Examples 1 to 6, Comparative Examples 1 to 4) A hair transforming cosmetic composition having the composition shown in Table 1 below was prepared by stirring and mixing the ingredients until uniform. The curling effect and damage to hair were evaluated when the obtained hair transforming cosmetic composition was used as a first agent for permanent waving using a normal rod, using the following methods.

[0021] Also, a 10% by mass aqueous solution of sodium bromate is prepared as the second agent.

[0022] <Creating test hair bundles for permanent waves> A 30 cm long, 10 g weight black human hair bundle was treated twice with a commercially available powder bleach, washed twice with a commercially available shampoo, treated with a commercially available hair treatment, and thoroughly towel-dried to prepare a test hair bundle for permanent waves.

[0023] <Permanent wave treatment> The test hair bundle for permanent waves was wrapped around a standard rod with a diameter of 20 mm, and 10 g of the first permanent wave agent listed in Table 1 was applied and left at 45°C for 10 minutes. The first permanent wave agent was then thoroughly rinsed off with hot water. Next, 15 g of the second agent was applied and left at room temperature for 10 minutes. The hair was then removed from the standard rod, and the second agent was thoroughly rinsed off with hot water. The hair was thoroughly towel-dried, styled with a comb, and hung vertically with one end of the hair bundle fixed. Leave at room temperature for 24 hours.

[0024] <Evaluation of curling effect> The evaluation was carried out by three hairdressers with over 10 years of experience, using the following criteria. <Evaluation criteria> 1. There is almost no curl. 2. The curls are weak. 3. The curls are a little weak but still neat. 4. The curls are beautiful. 5. The curls are nicely done.

[0025] <Damage evaluation> The evaluation was carried out by three hairdressers with over 10 years of experience, using the following criteria. <Evaluation criteria> 1. Rough texture. 2. Slightly rough to the touch. 3. Smooth texture. 4. Smooth to the touch. 5. Very smooth to the touch.

[0026] [Table 1]

[0027] As shown in Examples 1 to 6, when thioglycolic acid, cysteamine, and an organic acid having a higher pKa than thioglycolic acid were contained and the pH was adjusted to 8.0 or less with a basic amino acid, satisfactory evaluations of curling effect and damage were obtained. In contrast, as shown in Comparative Examples 1 to 4, when an organic acid having a lower pKa than thioglycolic acid was used, the evaluation of curling effect was insufficient.

[0028] (Examples 7 to 10, Comparative Examples 5 to 6) A hair transforming cosmetic composition having the composition shown in Table 2 below was prepared by stirring and mixing the ingredients until uniform. The curling effect and damage caused by using the obtained hair transforming cosmetic composition as a first agent for permanent waving with a heating rod were evaluated by the following methods.

[0029] <Creating test hair bundles for permanent waves using a heating rod> A 30 cm long, 10 g weight bundle of black human hair was treated with powdered bleach, washed twice with a commercially available shampoo, treated with a commercially available hair treatment, and thoroughly towel-dried to prepare a test bundle for permanent waves.

[0030] <Permanent wave treatment using a heating rod> 10 g of each of the permanent wave first agents listed in Table 2 was applied to a test hair bundle for permanent waves and left for 10 minutes. The first agent was then thoroughly rinsed off with hot water and thoroughly towel-dried. The hair was then wrapped around a 20 mm diameter heating rod and left to dry at 70°C. 15 g of each of the second agents was applied and left at room temperature for 10 minutes. The hair was then removed from the heating rod and the second agent was thoroughly rinsed off with hot water. The hair was thoroughly towel-dried, styled with a comb, and hung vertically with one end of the hair bundle secured, leaving it at room temperature for 24 hours.

[0031] <Evaluation of curling effect> The evaluation was carried out by three hairdressers with over 10 years of experience, using the following criteria. <Evaluation criteria> 1. There is almost no curl. 2. The curls are weak. 3. The curls are a little weak but still neat. 4. The curls are beautiful. 5. The curls are nicely done.

[0032] <Damage evaluation> The evaluation was carried out by three hairdressers with over 10 years of experience, using the following criteria. <Evaluation criteria> 1. Rough texture. 2. Slightly rough to the touch. 3. Smooth texture. 4. Smooth to the touch. 5. Very smooth to the touch.

[0033] [Table 2]

[0034] As shown in Examples 7 to 10, when thioglycolic acid, cysteamine, and an organic acid having a higher pKa value than thioglycolic acid were contained and the pH was adjusted to 8.0 or less with a basic amino acid, satisfactory evaluations of curling effect and damage were obtained. In contrast, as shown in Comparative Examples 5 and 6, when the pH exceeded 8.0, the evaluation of damage was insufficient.

[0035] (Examples 11 to 14, Comparative Examples 7 to 8) A hair transforming cosmetic composition having the composition shown in Table 3 below was prepared by stirring and mixing the ingredients until uniform. The straightening effect of the obtained hair transforming cosmetic composition when used as a first agent for straightening hair was evaluated by the following method.

[0036] <Creating a test hair bundle for straightening hair> A bundle of naturally curly hair (Indian black hair) measuring 30 cm in length when stretched and weighing 3 g was treated with a commercially available oxidative hair dye at level 12, washed twice with a commercially available shampoo, and thoroughly towel-dried to prepare a test bundle for straightening. <Hair straightening treatment> 6 g of each of the straightening agents listed in Table 3 was applied to the test hair bundle and left at 40°C for 15 minutes. The straightening agent was then thoroughly rinsed off with hot water. The hair was thoroughly towel-dried, then dried with a hair dryer, and straightened with a hair straightening iron heated to 180°C for 10 seconds. Next, 9 g of each of the second agents was applied, left at room temperature for 15 minutes, and the second agent was thoroughly rinsed off with hot water. The hair was thoroughly towel-dried, styled with a comb, and hung vertically with one end of the hair bundle secured, then left at room temperature for 24 hours.

[0037] <Straightening effect evaluation> The evaluation was carried out by three hairdressers with over 10 years of experience, based on the above criteria. <Evaluation criteria> 1. The hair is still frizzy and difficult to manage. 2. There is still some curl left and it is a little difficult to manage. 3. There is still a slight curl, but it is still manageable. 4. The curls have been mostly straightened out and the hair is easy to manage. 5. The curls are straightened and the hair is shiny and manageable.

[0038] <Damage evaluation> The evaluation was carried out by three hairdressers with over 10 years of experience, using the following criteria. <Evaluation criteria> 1. Rough texture. 2. Slightly rough to the touch. 3. Smooth texture. 4. Smooth to the touch. 5. Very smooth to the touch.

[0039] [Table 3]

[0040] As shown in Examples 11 to 14, when a composition containing thioglycolic acid, cysteamine, and an organic acid having a pKa value higher than that of thioglycolic acid was used, the pH was adjusted to 8.0 or lower with a basic amino acid, and the composition contained an organic acid having a pKa value higher than that of thioglycolic acid that neutralized 80% or more of the cysteamine content, sufficient evaluations of the straightening effect and damage were obtained.In contrast, as shown in Comparative Examples 7 and 8, when a composition containing an organic acid having a pKa value higher than that of thioglycolic acid that could only neutralize less than 80% of the cysteamine content was used, the evaluation of the straightening effect was insufficient.

Claims

1. A hair transforming cosmetic composition characterized by containing thioglycolic acid, cysteamine, and an organic acid having a higher pKa value than thioglycolic acid, and having a pH adjusted to 8.0 or less with a basic amino acid.

2. 2. The hair transforming cosmetic composition according to claim 1, wherein the content of the organic acid having a higher pKa value than thioglycolic acid is a content that neutralizes 80% or more of the cysteamine content.

3. The hair transforming cosmetic composition according to any one of claims 1 to 2, characterized in that the organic acid having a higher pKa value than thioglycolic acid is lactic acid, glycolic acid, succinic acid, or levulinic acid.

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