JP6367548B2 - First agent for two-component oxidative hair dyes - Google Patents

Description

  TECHNICAL FIELD The present invention relates to a first agent for two-component oxidative hair coloring / decoloring agent used for oxidative hair coloring and decoloring of hair, and is particularly effective in reducing the irritating odor caused by an alkaline agent during treatment. The present invention relates to a first agent for two-component oxidative hair dye / bleaching agent that enables hair dyeing and decolorization.

  The two-component oxidative hair dye is composed of a first agent containing an oxidative dye or an alkaline agent as a main component and a second agent containing an oxidant such as hydrogen peroxide. Most commonly used. Such a two-component oxidative hair dye is used by mixing the first agent and the second agent at the time of use. The two-component oxidative decoloring agent is one in which no oxidative dye is blended in the first agent, and is commonly used in the same manner as the two-component oxidative hair dye. In the following, the two-component oxidative hair dye and the first agent used in the oxidative decoloring agent are combined to be referred to as “first oxidative hair dye / decoloring agent first agent” (hereinafter simply referred to as “first agent”). There are things).

  Examples of the alkaline agent used for the first agent for two-component oxidative hair dye / bleaching agent generally include ammonia, alkanolamine, carbonate (for example, ammonium hydrogen carbonate), and the like. Among them, since ammonia has a small molecular weight, it has an advantage that melanin in hair can be efficiently decomposed with a smaller blending amount than alkanolamine, and damage to hair after treatment can be reduced.

  In recent years, many oxidative hair dyes and depigmenting agents have been developed in which alkaline agents such as ammonia and ammonium hydrogen carbonate are blended in the formulation. However, when a certain amount or more of ammonia or ammonium hydrogen carbonate is blended in the system, there is a problem that an irritating odor is generated.

  Various techniques for reducing the irritating odor have been proposed so far. For example, Patent Document 1 proposes a method of using alkanolamine or inorganic alkali with a little irritating odor instead of ammonia. Moreover, in patent document 2, the irritation odor is reduced by mix | blending an isoparaffin, a nonionic surfactant, and a high molecular compound.

  There has also been proposed a technique that enables a reduction in ammonia odor by forming a liquid crystal structure in the prepared cream particles and confining ammonia molecules in the liquid crystal structure (for example, Patent Documents 3 and 4). In recent years, such a technique has been widely used in many hair color preparations. However, even when such a technique is used, when a certain amount of ammonia or ammonium hydrogen carbonate is contained as an alkaline agent, the reduction of the irritating odor based on these components is not sufficient.

  On the other hand, a foam hair dye containing an N-acylamino acid salt and a diallyldimethyl quaternary ammonium copolymer has been proposed as a first agent for two-component oxidative hair dye / bleaching agent. There is no description or suggestion about problems and effects peculiar to a two-component hair dye aimed at reducing hair loss (Patent Document 5). On the other hand, for lysine sodium dilauroylglutamate, hair dyes using inorganic pigments have been proposed, but no description or suggestion as a two-part hair dye has been made (Patent Document 6).

JP 2004-189717 A JP 2003-221319 A JP 2004-189638 A JP 2003-040750 A JP 2012-072128 A JP 2012-144580 A

  The present invention has been made under such circumstances, and its object is to reduce the irritating odor caused by the alkaline agent at the time of treatment and to enable effective hair dyeing and decoloring. It is in providing the 1st agent for use.

  The first agent for two-component oxidative hair dye / bleaching agent of the present invention that has achieved the above-mentioned object is a two-component oxidative dye used at the time of oxidative hair dyeing or decoloring at least an alkali agent. The first agent for hair and depigmenting agent has a gist in that it contains (a) an N-stearoyl amino acid salt and (b) a nonionic surfactant.

  In the first agent for two-component oxidative hair dye / bleaching agent of the present invention, the content of the (a) N-stearoyl amino acid salt is the proportion of the entire first agent for two-agent oxidative hair dye / bleaching agent. Is preferably 5% by mass or less (excluding 0% by mass).

  The (a) N-stearoyl amino acid salt is preferably at least one selected from the group consisting of sodium N-stearoyl-L-glutamate, sodium N-stearoyl-L-aspartate, and sodium N-stearoyl-L-sarcosine. It is mentioned as a thing.

  The nonionic surfactant (b) has an HLB value of 15 or more, and the content of the nonionic surfactant is 10% by mass or less (0% by mass) based on the total amount of the first agent for two-component oxidative hair dye / bleaching agent. Is not included).

  In the first agent for two-component oxidative hair dye / bleaching agent of the present invention, if necessary, (c) dilauroyl glutamic acid sodium lysine can also be contained, thereby reducing the irritating odor caused by the alkaline agent, Effective hair dyeing and decolorization will be even better. (C) The content of lysine sodium dilauroylglutamate is preferably 5% by mass or less as a proportion of the entire first agent for two-component oxidative hair dye / bleaching agent.

  In the first agent for two-component oxidative hair dye / bleaching agent of the present invention, (d) xanthan gum can be further contained if necessary, and this makes the operability such as mixing property and applicability of the first agent. Will be improved. (D) The content of xanthan gum is preferably 1% by mass or less in terms of the proportion of the entire first agent for two-component oxidative hair dye / bleaching agent.

  The first agent for two-component oxidative hair dye / bleaching agent of the present invention may further contain (e) sodium polyaspartate, if necessary, thereby improving the water retention of the hair after hair dyeing. However, the condition (sliding, fingering, etc.) is good.

  According to the present invention, by containing at least an alkaline agent and containing an N-stearoyl amino acid salt and a nonionic surfactant, an irritating odor at the time of treatment can be suppressed. The first agent for two-component oxidative hair dye / bleaching agent that promotes the penetration of the medicine into the hair with a blending amount of the alkaline agent at a lower concentration than the agent and enables effective hair dyeing and decolorization can be realized.

  The present inventors have studied from various angles in order to realize a first agent for two-component oxidative hair dye / bleaching agent that meets the above-mentioned purpose. As a result, the inventors have found that the above object can be achieved brilliantly when (a) an N-stearoyl amino acid salt and (b) a nonionic surfactant are contained, thereby completing the present invention.

  The first agent for two-component oxidative hair dye / bleaching agent of the present invention contains at least the components (a) and (b) in combination, and the action of each component will be described.

  The N-stearoyl amino acid salt [the above component (a)] is a component necessary for reducing the irritating odor caused by the alkaline agent and allowing the alkaline agent, dye, and the like to penetrate efficiently into the hair. These effects increase as the content increases, but in order to exhibit more effectively, 0.1% by mass or more (ratio to the entire first agent for two-component oxidative hair dye / bleaching agent) It is preferable to make it. More preferably, it is 0.3 mass% or more. However, if the content is excessive, the effect of suppressing the irritating odor, the dyeability and the operability are deteriorated. More preferably, it is 4 mass% or less.

  Examples of amino acid residues of the N-stearoyl amino acid salt include glutamic acid, aspartic acid, glycine, and β-alanine. Examples of these salts include sodium, potassium, lithium, ethanolamine, diethanolamine, triethanolamine and the like. Here, specific examples of N-stearoyl amino acid salts include N-stearoyl-L-glutamate sodium, N-stearoyl-L-sodium aspartate, N-stearoyl-L-sarcosine sodium, N-stearoyl-N-methyl-β. Alanine sodium etc. can be mentioned and 1 or more types of these can be used.

  On the other hand, the nonionic surfactant [the component (b)] is necessary for suppressing the irritating odor caused by the alkaline agent and allowing the alkaline agent or dye to efficiently penetrate into the hair, as with the component (a). Is an essential ingredient. These effects increase as the content increases, but in order to exhibit more effectively, 0.5% by mass or more (ratio to the entire first agent for two-component oxidative hair dye / bleaching agent) It is preferable to make it. More preferably, it is 1 mass% or more. However, when the content of the nonionic surfactant is excessive, the effect of suppressing the irritating odor is deteriorated and the mixing property with the second agent is also deteriorated. Therefore, the content is preferably 10% by mass or less. More preferably, it is 8 mass% or less.

  The nonionic surfactant used in the present invention preferably has an HLB value (hydrophilic-lipophilic balance value) of 15 or more. This HLB value is a measure of the balance between the hydrophilicity and lipophilicity of a nonionic surfactant, expressed as a number (HLB: Hydrophile-Lipophile Balance). The larger the size, the greater the hydrophilicity, and the smaller the size, the higher the lipophilicity. Generally, those having an HLB value of 5 or less are sometimes referred to as lipophilic nonionic surfactants, and those having an HLB value of 15 or more are referred to as hydrophilic nonionic surfactants. The value of HLB can be calculated from the well-known Griffin equation (for example, “Cosmetics and Science”, Asakura Shoten, September 20, 2001, page 55).

  Examples of the nonionic surfactant having an HLB value of 15 or more include polyoxyethylene cetyl ether and polyoxyethylene stearyl having an added mole number of ethylene oxide chain (hereinafter sometimes abbreviated as “POE”) of 20 moles or more. Examples include ether, polyoxyethylene behenyl ether, polyoxyethylene oleyl ether, polyoxyethylene octyldodecyl ether, and the like, and one or more of them can be used.

  By combining the components (a) and (b) as described above, the irritating odor caused by the alkaline agent (especially ammonia or ammonium hydrogen carbonate) can be reduced, and the alkaline agent or dye can be efficiently penetrated into the hair. Can be made. The reason why such an effect is exerted is not completely understood, but could probably be considered as follows. That is, it is considered that a composition containing (a) an N-stearoyl amino acid salt and (b) a nonionic surfactant forms a stable aggregate and retains an alkali agent, a dye or the like in the system. Therefore, it is presumed that effective dyeing and decoloring will be possible because alkaline agents and dyes can be efficiently penetrated into the hair when applied to the hair without releasing an irritating odor into the air. .

  The first agent for two-component oxidative hair dye / bleaching agent of the present invention basically contains the above-mentioned components (a) and (b), but if necessary, it contains (c) lysine sodium dilauroyl glutamate. Is also preferable. (C) By containing sodium lauryl dilauroyl glutamate, the irritating odor caused by the alkaline agent can be further reduced, and the alkaline agent, dye, and the like can be efficiently penetrated into the hair.

  Dilauroyl glutamic acid lysine sodium is a sodium salt of a condensate of N-lauroyl-L-glutamic acid and L-lysine, and is a gemini-type anionic surfactant. High interface that enables micelle formation even at low concentrations compared to surfactants such as single-chain N-lauroyl-L-glutamate because it has two lauroyl groups in a single molecule (gemini type) It is a compound having active ability.

  The content of (c) dilauroyl glutamic acid sodium lysine as described above is 5% by mass or less (not including 0% by mass) in the proportion of the entire first agent for two-component oxidative hair dye / bleaching agent ) Is preferable. If this content exceeds 5% by mass, the effect of reducing the irritating odor, dyeability and operability are worsened. Moreover, in order to exhibit such an effect effectively, it is preferable to contain 0.5 mass% or more (ratio to the whole 1st agent for 2 agent type oxidative hair dye and a decoloring agent). More preferably, it is 1 mass% or more.

  It is also effective to add (d) xanthan gum to the first agent for two-component oxidative hair dye / bleaching agent of the present invention, if necessary. (D) Xanthan gum is a kind of natural polysaccharide, and among many natural polysaccharides, it has characteristics that are excellent in stability under various conditions such as salt resistance, high-temperature stability, and alkali resistance.

  (D) Xanthan gum is a polysaccharide obtained by fermenting carbohydrates such as starch, glucose, sucrose using Xanthomonas spp., And purified by centrifugation, filtration, etc. after fermentation Those purified by enzyme treatment may be used. Moreover, you may use what performed the process by a heating and an organic solvent.

  (D) Xanthan gum forms a gel network in the aqueous phase, reduces the irritating odor of the alkaline agent, can impart an appropriate viscosity to the preparation, and is an effective component for improving operability. These effects increase as the content increases, but in order to exhibit more effectively, 0.01% by mass or more (ratio to the entire first agent for two-component oxidative hair dye / bleaching agent) It is preferable to do. More preferably, it is 0.05 mass% or more. However, if the content of xanthan gum is excessive, it becomes too viscous and the operability deteriorates, so it is preferable to make it 1% by mass or less. More preferably, it is 0.8 mass% or less.

  The first agent for two-component oxidative hair dye / bleaching agent of the present invention preferably contains (e) sodium polyaspartate, if necessary. (E) The hair treated with the first agent containing sodium polyaspartate has good finger passage through the hair. In order to exhibit such an effect, it is preferable to make it contain so that it may become 0.01 mass% or more (ratio to the whole 1st agent for 2 agent type oxidation hair dye and a decoloring agent). More preferably, it is 0.1 mass% or more. However, when the content of (e) sodium polyaspartate is excessive, sodium polyaspartate is excessively adhered to the hair and the finger is deteriorated. Therefore, the content is preferably 10% by mass or less. More preferably, it is 8 mass% or less.

  As for the alkaline agent contained in the first agent for two-component oxidative hair dye / bleaching agent of the present invention, representative examples thereof include ammonia and ammonium hydrogen carbonate. The effect is exhibited effectively. However, the alkaline agent contained in the first agent for two-component oxidative hair dye / bleaching agent of the present invention is not limited to ammonia and ammonium hydrogen carbonate, but also monoethanolamine, triethanolamine, 2-amino-2-methyl Alkanolamines such as -1-propanol, inorganic alkalis such as sodium hydroxide, potassium hydroxide, sodium carbonate and potassium carbonate, basic amino acids such as arginine and lysine or salts thereof can be used in combination.

  The first agent for two-part oxidative hair dye / bleaching agent of the present invention is intended to include both an oxidative hair dye and a decoloring agent, but as an oxidative dye blended when used as an oxidative hair dye, For example, paraphenylenediamine, toluene-2,5-diamine, paraaminophenol, etc. can be mentioned. When used as an oxidative hair dye, a coupler can be blended if necessary. Examples of such couplers include α-naphthol, resorcin, metaaminophenol, 2,4-diaminophenoxyethanol, paraamino orthocresol, 5- (2-hydroxyethylamino) -2-methylphenol, and the like. In addition to the above substances, those described in "Quasi-drug raw material standard 2006" (Pharmaceutical Daily) can be used as appropriate. Furthermore, acidic dyes, basic dyes, HC dyes, and the like can be blended.

  The first agent for two-component oxidative hair dye / bleaching agent of the present invention may contain an additive which is usually contained. Examples of such additives include humectants, oils (fats), silicones, cationized polymers, gelling agents, chelating agents, antioxidants, pH adjusters, stabilizers, solvents, anti-inflammatory agents, perfumes, and dyes. Etc. can be normally blended.

  The best dosage form of the first agent for the two-component oxidative hair dye / bleaching agent of the present invention is a cream containing a higher alcohol which is an oil (fat) agent such as cetanol, cetostearyl alcohol, stearyl alcohol, etc. However, it can also be used in a gel-like dosage form or a liquid dosage form.

  Next, the present invention will be described more specifically by way of examples. However, the following examples are not intended to limit the present invention, and all modifications can be made without departing from the spirit of the above and following descriptions. To be included in the scope.

  Various raw materials were blended at various blending ratios shown in Table 1 below to prepare a second agent for two-component oxidative hair dye / bleaching agent (hereinafter simply referred to as “second agent”). In the following examples, the second agent shown in Table 1 was used. In Table 1, “POE cetyl ether” represents polyoxyethylene cetyl ether. The numerical value in () after “POE cetyl ether” represents the number of moles of ethylene oxide (the same applies to Tables 2 to 8 below).

Example 1
Various raw materials were blended at various blending ratios shown in Tables 2 to 7 below to prepare a first agent for two-component oxidative hair dye / bleaching agent. Using the first agent and the second agent shown in Table 1, each item was evaluated by the following method. The results are also shown in Tables 2-7 below.

(Evaluation method of irritating odor)
Various first agents whose component compositions are shown in Tables 2 to 7 below and the second agent shown in Table 1 are mixed so as to be 1: 1 (mass ratio), and an expert panelist regarding the odor of the mixture ( 20 persons) conducted a sensory test, and the total value was obtained and evaluated according to the following criteria.

(Evaluation criteria for irritating odors)
3 points: no irritating odors 2 points: irritating odors are observed but hardly felt 1 point: irritating odors are observed (standard of total value)
◎: 50 or more and 60 or less ○: 40 or more and less than 50 △: 30 or more and less than 40 × ×: less than 30

(Dyeing Evaluation Method I)
The chemical composition (oxidative hair dyeing and hair-dyeing) is obtained by mixing the first agent whose component composition is shown in Tables 2 to 7 below and the second agent shown in Table 1 so as to be 1: 1 (mass ratio). It was applied to a hair bundle (10 cm, 1.0 g, 100% gray hair) derived from a person who had not been subjected to decoloring treatment, and allowed to stand at 35 ° C. for 30 minutes. Subsequently, it was washed with water, washed with a 10% aqueous solution of triethanolamine lauryl sulfate, and then air-dried. At this stage, the degree of dyeing of the hair bundle was visually observed by a professional panelist (10 persons), and the total value was obtained and evaluated according to the following criteria. It changes from light brown to dark brown depending on the degree to which the hair bundle is dyed.

(Evaluation criteria I for staining)
3 points: Excellent dyeability (dye deeply)
2 points: good dyeability (slight dyeing is light)
1 point: Poor dyeability (light dyeing)
(Total value standard)
◎: 25 or more and 30 or less ○: 20 or more and less than 25 △: 15 or more and less than 20 × ×: less than 15

(Dyeing evaluation method II)
The chemical composition (oxidative hair dyeing and hair-dyeing) is obtained by mixing the first agent whose component composition is shown in Tables 2 to 7 below and the second agent shown in Table 1 so as to be 1: 1 (mass ratio). It was applied to a hair bundle (10 cm, 1.0 g, 100% gray hair) derived from a person who had not undergone decoloring treatment, and allowed to stand at 35 ° C. for 30 minutes. Subsequently, it was washed with water, washed with a 10% aqueous solution of triethanolamine lauryl sulfate, and then air-dried.

L ^* , a ^* , and b ^* of the hair bundle subjected to the above treatment are measured with a color difference meter (manufactured by Nippon Denshoku Industries Co., Ltd., “Spectro color Meter SE2000”), and oxidative dyeing is performed by comparing the L ^* values. The degree of dyeing of the hair agent (brown) was evaluated according to the following criteria. The smaller the L ^* value, the higher the dyeability and the darker the color.

◎: L ^* value less than 24.00 ○: L ^* value 24.00 or more, less than 24.50 Δ: L ^* value 24.50 or more, less than 25.00 ×: L ^* value 25.00 or more

(Evaluation method for operability)
Specializing in applicability to the hair when the first agent whose composition is shown in Table 7 below and the second agent shown in Table 1 are mixed 1: 1 (mass ratio) and the mixture is applied to the hair. Panelists (10 persons) conducted a sensory test, and the total value was obtained and evaluated according to the following criteria.

(Evaluation criteria for operability)
3 points: Excellent applicability (easy to apply)
2 points: moderate applicability (easy to apply moderately)
1 point: Poor applicability (hard to apply)
(Total value standard)
◎: 25 or more and 30 or less ○: 20 or more and less than 25 △: 15 or more and less than 20 × ×: less than 15

  Formulation examples 1 to 4 in Table 2 are evaluated for the presence or absence of the components (a) to (c), the blending amount, or the functionality when replaced with other components.

  Prescription Examples 1 to 3 in Table 2 are the results of evaluating the presence or absence of the components (a) and (b). From this, only when the components (a) and (b) were blended (Formulation Example 3), the effect of reducing the irritating odor and the dyeability were good. This is because, by blending (a) N-stearoyl amino acid salt and (b) nonionic surfactant, a stable aggregate can be obtained even in an environment containing a large amount of salts such as alkaline agents and dyes such as hair color. I think it is because it can be formed.

  In addition, it was found that when (c) dilauroyl glutamic acid sodium lysine was blended (Formulation Example 4), although the effect of reducing the irritating odor and the dyeability were slight, even better results were obtained. This is considered to be because the addition of lysine sodium dilauroylglutamate can not only improve the permeability but also stabilize the above-mentioned aggregate.

  Formulation examples 5 to 13 in Table 3 are the results of evaluating the performance of the component (a) when other ionic (amphoteric) surfactants are combined. In various ionic (amphoteric) surfactants using an amino acid sodium salt having an N-stearoyl group (formulation examples 5 and 6), each evaluation of irritation, dyeability I and dyeability II Good results were observed. In addition, when N-lauroyl-L-aspartate sodium (formulation example 7) or N-coconut oil fatty acid acyl-L-glutamate sodium (formulation example 8) is used, even in the same amino acid salt, but the added alkyl group is different The evaluation of irritation, dyeability I and dyeability II is poor, and generally used anionic surfactants (formulation examples 9 and 10), amphoteric surfactants (formulation examples 11 and 12) and cationic properties are used. Similarly, the evaluation results for the surfactant (Formulation Example 13) also deteriorated. This indicates that the component (a) having an amino acid salt and an N-stearoyl group in the molecule is an important factor for forming a stable aggregate.

  Formulation Example 3 and Formulation Examples 14 to 27 in Tables 4 and 5 evaluate the case where a nonionic surfactant having a different HLB is combined for component (b). Among the nonionic surfactants, those using a hydrophilic nonionic surfactant having an HLB of 15 or more (formulation examples 3, 15, 16, and 18) are lipophilic nonionic surfactants having an HLB of 5 or less. As compared with those using the formula (Prescription Examples 19 to 22), good evaluation results were observed. Also in this regard, it is considered that the hydrophilic surfactant forms a better aggregate than the lipophilic nonionic surfactant in combination with the N-stearoyl-L-amino acid salt.

  In the case where two types of hydrophilic nonionic surfactants are combined (formulation example 23, 25 to 27) and the case where a lipophilic nonionic surfactant and a hydrophilic nonionic surfactant are combined (formulation example 24). Moreover, the favorable evaluation result was shown by mix | blending nonionic surfactant whose HLB value is 15 or more (Table 5).

  Formulation Example 3 and Formulation Examples 28 to 33 in Table 6 are the results of evaluating the influence of the compounding amounts of components (a) and (b) on the performance. From this, it was found that (a) sodium N-stearoyl-L-glutamate is most effective when incorporated in an amount of about 0.3% by mass (formulation example 29). Moreover, when it became 5 mass% or more, the result was a little inferior (prescription example 30). (B) About 1% by mass of POE cetyl ether shows the best results (Formulation Example 32), but when 10% by mass is blended, the performance tends to deteriorate (Formulation Example 33).

  Formulation examples 34 to 36 in Table 7 evaluate the performance when (d) xanthan gum and other types of thickeners are blended in addition to components (a) and (b). From this result, it was found that the most excellent operability was obtained when (d) xanthan gum was added to this system. This is considered to be because the function can be exhibited most in this prescription system.

  Formulation examples 37 to 39 in Table 7 examine the influence of the amount of (d) xanthan gum on the performance. From this, a good result was obtained by blending 0.05% by mass or more of (d) xanthan gum (Formulation Example 38), and when 1% by mass was blended, the performance was inferior (Formulation Example 39).

(Example 2)
Regarding the damage and feel imparted to hair after hair dyeing in the first agent for oxidative hair coloring / decoloring agent, “damage after hair dyeing (hair breaking strength)”, “slip after hair dyeing (coefficient of friction of hair) ) "," Moisturizing feeling after hair dyeing (hair moisture content) ".

  Various raw materials were blended at the blending ratios shown in Table 8 below to prepare the first agent for oxidative hair dye. Using the first agent and the second agent shown in Table 1, each item was evaluated by the following method. The results are also shown in Table 8 below.

(Evaluation method of the degree of damage after hair dyeing (breaking strength of hair))
Chemical treatment (oxidative hair dyeing / decoloration treatment, etc.) obtained by mixing various first agents shown in Table 8 below and the second agent shown in Table 1 so as to be 1: 1 (mass ratio) ) 0.2 g was applied to a hair bundle (15 cm, 0.2 g) of human-derived hair that did not receive the above. Thereafter, the mixture was allowed to stand at 35 ° C. for 30 minutes and washed with a 10% aqueous solution of triethanolamine lauryl sulfate. This series of operations is performed five times, and each sample hair is arbitrarily selected from the obtained treated hairs, and the hair diameter [major axis (mm) and minor axis (mm) is measured by “Hair Diameter Measurement System” (manufactured by Kato Tech Co., Ltd.). )] Was measured, and the cross section (mm ² ) of the hair was determined from the following formula (1). Next, the tensile break value (cN) of the sample hair in water was measured using a tabletop material testing machine [Tensilon STA-1150] (manufactured by Orientec Co., Ltd.). Thereafter, the tensile strength at break (cN / mm ² ) per cross section (mm ² ) was calculated to obtain the breaking strength (cN / mm ² ) (n = 10). The evaluation criteria at this time are as follows.
Cross section (mm ² ) = (π / 4) × major axis (mm) × minor axis (mm) (1)

(Evaluation criteria for hair damage)
A: The breaking strength of the hair is 1.70 × 10 ⁴ cN / mm ² or more. ○: The breaking strength of the hair is 1.65 × 10 ⁴ cN / mm ² or more and less than 1.70 × 10 ⁴ cN / mm ² Δ: Hair breaking strength of 1.60 × 10 ⁴ cN / mm ² or more, less than 1.65 × 10 ⁴ cN / mm ² ×: Hair breaking strength of less than 1.60 × 10 ⁴ cN / mm ²

(Evaluation method of slip after hair dyeing (coefficient of friction of hair))
“Slip after hair dyeing” was evaluated by measuring the friction coefficient of hair after hair dyeing. The coefficient of friction was determined by subjecting hair (10 cm, 1 g) not subjected to chemical treatment to hair dyeing treatment performed by measuring the breaking strength twice, and then washing with a 10% aqueous solution of triethanolamine lauryl sulfate and then wet. The friction coefficient μ of the treated hair was measured. Various conditions used for the measurement are described below.
(1) Initial value setting: The initial value was measured in order to select a hair bundle having the same characteristics.
(2) Humidity adjustment of hair: The hair bundle for measurement was conditioned at 20 ° C. and 60% humidity for 24 hours or more.
(3) Measuring instrument: For the measurement, a friction tester “KES-SE” (manufactured by Kato Tech Co., Ltd.) was used.
(4) Measurement was performed under the conditions of measurement sensitivity: H, frictional static load: 50 gf, sensor: silicon type. Scanning was performed in the forward direction (hair bundle from the root). The coefficient of friction (μ) was measured by multiplying the MIU value by a coefficient of 0.1.

(Evaluation criteria for slip after hair dyeing)
A: Friction coefficient μ is less than 0.50 B: Friction coefficient μ is 0.50 or more and less than 0.60 Δ: Friction coefficient μ is 0.60 or more and less than 0.70 ×: Friction coefficient μ is 0.70 or more

(Method for evaluating moisturizing feeling after hair dyeing (hair moisture content))
The moisturizing feeling after dyeing was evaluated by measuring the moisture content of the hair after dyeing. The moisture content of the hair is measured by chemically treating the first agent whose component composition is shown in Table 8 below and the second agent shown in Table 1 so as to be 1: 1 (mass ratio). Untreated hair that had not been applied was applied to a hair bundle of 20 cm and 0.25 g. Thereafter, the mixture was allowed to stand at 35 ° C. for 30 minutes, washed with a 10% aqueous solution of triethanolamine lauryl sulfate, and then air-dried. This operation was repeated 5 times, and the hair that had been allowed to stand for 24 hours at 20 ° C. and 60% humidity was conditioned and used as moisture measuring hair.

(Hair moisture measurement)
A Karl Fischer moisture measuring device (manufactured by Diane Instruments) was used to measure the hair moisture content. The measured hair was heated at 200 ° C. for 10 minutes using a moisture vaporizer that is an accessory of the Karl Fischer moisture measuring device to evaporate moisture in the hair. Thereafter, the amount of water evaporated by coulometric titration was quantified, and the moisture content of the hair was calculated from the following formula.
Moisture content (%) = water content (mg) / hair mass (mg) × 100
However, hair mass: mass before charging-mass after charging

(Evaluation criteria for hair moisturizing feeling)
A: Hair moisture percentage is 14.0% or more. O: Hair moisture percentage is 13.5% or more and less than 14.0%. Δ: Hair moisture percentage is 13.0% or more and less than 13.5%. Is less than 13.0%

  As is clear from Formulation Example 34 and Formulation Examples 40 to 42 in Table 8, the compounds (prescription examples 34 and 40) in which the components (a), (b) and (d) are blended are not blended (prescription) Compared to Example 41) and those containing a cationic polymer (Formulation Example 42), it was possible to suppress a reduction in hair strength after hair dyeing, and the water content was also good. This is considered because the component (a) sodium N-stearoyl-L-glutamate not only acts as a surfactant but also acts as a conditioning component derived from amino acids. In addition, it was found that when (e) sodium polyaspartate was added, the friction coefficient was further reduced and the slip was improved. This was considered to be because sodium polyaspartate formed a film on the hair surface after dyeing.

Claims (9)

In the first agent for two-component oxidative hair coloring / decoloring agent, which contains at least one of ammonia water and ammonium hydrogen carbonate as an alkaline agent , and is used for oxidative hair coloring or decoloring hair,
Containing (a) an N-stearoyl amino acid salt, and (b) a nonionic surfactant ,
Content of said (a) N-stearoyl amino acid salt is 0.1 mass% or more in the ratio which occupies for the whole 1st agent for two-component oxidative hair dye and decoloring agent, The two-component oxidative dyeing characterized by the above-mentioned First agent for hair and depigmenting agent (excluding one agent of the following composition;
Cetostearyl alcohol: 3%
Stearyl alcohol: 3%
Paraffin wax 115 ° F .: 3.1%
Isopropyl isostearate: 2%
N-coconut oil fatty acid acyl glutamic acid triethanolamine: 9%
Glyceryl stearate: 2.2%
POE (40) cetyl ether: 1.7%,
Dipropylene glycol: 1.3%
Aqueous ammonia (28%): 8.6%
Hydroxyethane diphosphonic acid (60%): 0.3%,
Purified water: Total remaining amount: 100%). The two-part oxidative hair dye according to claim 1, wherein the content of the (a) N-stearoyl amino acid salt is 5% by mass or less as a proportion of the whole first part for the two-part oxidative hair dye / bleaching agent. -The first agent for decolorizing agents.   The (a) N-stearoyl amino acid salt is at least one selected from the group consisting of sodium N-stearoyl-L-glutamate, sodium N-stearoyl-L-aspartate, and sodium N-stearoyl-L-sarcosine. Item 1. The first agent for a two-component oxidative hair dye / bleaching agent according to item 1 or 2.   The nonionic surfactant (b) has an HLB value of 15 or more, and the content of the nonionic surfactant is 10% by mass or less (0% by mass) based on the total amount of the first agent for two-component oxidative hair dye / bleaching agent. The first agent for a two-component oxidative hair dye / bleaching agent according to any one of claims 1 to 3.   Furthermore, the 1st agent for 2 agent type | formula oxidative hair dye and a decoloring agent in any one of Claims 1-4 containing (c) dilauroyl glutamic acid ricin sodium.   The two-part oxidative hair dye according to claim 5, wherein the content of (c) dilauroyl glutamic acid ricin sodium is 5% by mass or less as a percentage of the entire first part for the two-part oxidative hair dye / bleaching agent. -The first agent for decolorizing agents.   Furthermore, (d) 1st agent for 2 agent type oxidative hair dye and a decoloring agent in any one of Claims 1-6 containing a xanthan gum.   The content of the (d) xanthan gum is 1% by mass or less as a percentage of the entire first agent for a two-component oxidative hair dye / bleaching agent. First agent.   Furthermore, (e) 1st agent for 2 agent type | formula oxidative hair dye and a decoloring agent in any one of Claims 1-8 containing sodium polyaspartate.