JP2006298822A - Primary agent for straightening curly hair, curly hair-straightening agent and method of straightening treatment of curly hair - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a primary agent for a curly hair-straightening agent capable of inhibiting the damage of the hairs on a curly hair-straightening treatment and having an excellent curly hair-straightening function, a curly hair-straightening agent containing the primary agent for the curly hair-straightening agent as a constituting element, and a method of straightening treatment of the curly hair by using the curly hair-straightening agent. <P>SOLUTION: This primary agent for straightening the curly hair is characterized by blending at least ≤4.5 mass% reducing agent in terms of thioglycolic acid, ≥1 mass% dithioglycolic acid or its salt, further a polyoxyethylene alkyl ether phosphoric acid ester or its salt and a phosphoric acid ester other than the polyoxyethylene alkyl ether phosphoric acid ester, and having pH≤5. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a first agent for straightening hair, a straightening agent containing the first agent as a constituent, and a method for straightening curly hair using the straightening agent.

  Hair straightening is a technique for straightening curly hair, but the reaction theory of reducing and cleaving cystine bonds inside the hair is the same as that of permanent wave, and the basic components are the same as permanent wave agents. It is the same.

  The basic constituents of the hair straightening agent can be roughly divided into four main components: a reducing agent or oxidizing agent that is an active ingredient, an alkaline agent that is an auxiliary agent, an additive, and water. The reducing agent is a component necessary for reducing and cleaving the cystine bond inside the hair. Usually, the reducing agent's reducing power is enhanced by making the liquidity of the hair straightening agent alkaline with an alkaline agent. . Further, since the hair itself swells with the alkaline agent, the hair straightening agent containing the reducing agent easily penetrates, so that the action of the reducing agent on the hair increases.

  However, the reducing agent and alkaline agent added to the curly hair straightening agent are components that have the effect of ensuring and improving the curly hair straightening function, and are also components that cause hair damage. Therefore, the curly hair straightening agent is required to satisfy both of ensuring the hair straightening function and suppressing hair damage.

  In hair straightening, the treatment used (hair straightening agent) has the same components as the treatment agent in permanent wave (permanent wave agent), but the treatment method is different. ing. That is, in the permanent wave, the winding wound around the rod is performed, whereas in the hair straightening, the treatment is performed by combing (stretching with a comb and straightening) or high-temperature hairstyling iron. Therefore, damage to hair due to the active ingredient of the curly hair straightening agent is further increased by physical treatment such as treatment with combing or high-temperature hairstyling iron, and in some cases, hair breakage may be caused. Therefore, in straightening hair, it is required to suppress hair damage even in the above physical treatment.

  In curly hair straightening treatment, in order to suppress hair damage, reduce the amount of active ingredients such as reducing agents and oxidizing agents in the curly hair straightener, and reduce the amount of alkaline agent, etc. A technique is generally used in which the pH of the preparation is not so high. With such a technique, although chemical damage to hair by the curly hair straightening agent can be suppressed, the curly hair straightening action is reduced. In addition, damage to hair due to physical treatment such as combing or high-temperature hairstyling iron cannot be suppressed.

  In addition to this, various techniques for suppressing hair damage during curly hair straightening treatment have been proposed.

  For example, Patent Document 1 discloses a tweezers type straight blow brush or a shrinkable brush that can treat hair with a first agent for straightening hair, then wash off the first agent, dry to some extent, and then stretch the hair with the hair sandwiched between them. A method is disclosed in which a hair straightening tool is used to heat the hair while heating with a dryer, and then the hair is treated with a second hair straightener.

  Patent Document 2 discloses a hair straightener composition containing a diamide compound having a specific structure and an alkali agent, and having a pH of 12 to 14 when diluted 10 times with water.

  Furthermore, Patent Document 3 discloses a hair straightener containing an emulsion of a quaternary ammonium salt, a higher alcohol, and a polymer silicone having a specific structure.

JP 2004-223122 A JP 2003-327516 A JP 2002-326915 A

  Among them, in the technique of Patent Document 1, since the temperature applied to the hair is lowered by using a dryer instead of the high-temperature hair-styling iron, the hair damage due to this can be reduced, but the damage due to combing cannot be avoided. .

  The technique of Patent Document 2 suppresses hair damage during the hair straightening treatment by the action of the diamide compound having a specific structure contained in the hair straightener composition, but increases the activity of the diamide compound, A high pH setting to swell sufficiently causes hair damage.

  Regarding the technique of Patent Document 3, according to the study of the present inventor, after the hair straightener applied to the hair is rinsed off and dried with a drier, the treatment with a normal high-temperature hairstyling iron is performed. It was found that damage would occur.

  The present invention has been made in view of the above circumstances, and the purpose thereof is a first agent for straightening hair that can suppress hair damage during curly hair straightening treatment and has excellent curly hair straightening ability, An object of the present invention is to provide a curly hair straightening agent containing the first curly hair straightening agent as a component, and a method for straightening curly hair using the curly hair straightening agent.

  The first agent for straightening curly hair of the present invention that has achieved the above object is at least 4.5% by mass or less of the reducing agent in terms of thioglycolic acid, and 1% by mass of dithiodiglycolic acid or a salt thereof. More specifically, polyoxyethylene alkyl ether phosphate ester or a salt thereof and a phosphate ester other than polyoxyethylene alkyl ether phosphate ester are blended, and the pH is 5 or less. is there.

  Moreover, the hair straightening agent of the present invention comprises the first hair straightening agent of the present invention and at least a second agent for curly hair straightening containing at least an oxidizing agent. To do.

  Furthermore, the straightening treatment method for curly hair of the present invention is a method for straightening curly hair using the agent for straightening curly hair of the present invention, and after applying the first agent for straightening curly hair to the curly hair, The curly hair is straightened, the curly hair after the straightening is washed to remove the first curly hair straightening agent, and then the second curly hair straightening agent is applied to the curly hair for treatment. .

  According to the first hair straightening agent, the hair straightening agent, and the hair straightening treatment method of the present invention, it is possible to satisfactorily correct curly hair while suppressing chemical and physical damage.

<Hair straightener>
The agent for straightening hair of the present invention comprises the first agent for straightening hair of the present invention and the second agent for straightening hair.

  The first agent for straightening hair contains at least a reducing agent, dithiodiglycolic acid or a salt thereof, polyoxyethylene alkyl ether phosphate or a salt thereof, and a phosphate ester other than polyoxyalkyl ether phosphate. And the pH is 5 or less.

  The pH of the first agent for straightening hair is 5 or less. If the pH of the first agent for straightening hair is too high, hair damage during the straightening treatment becomes large, and the feel of the hair after treatment becomes poor. Note that, when the pH of the first agent for straightening hair is lowered, the hair straightening effect is usually impaired by reducing the permeability of the reducing agent to the hair. In the case of one agent, the composition of each component described later ensures the good curly hair straightening effect by sufficiently drawing out the action of the reducing agent even when the pH is lowered. Moreover, it is preferable that pH of the 1st agent for curly hair correction is 3.5 or more. In the first agent for straightening hair of the present invention, for example, by blending the components described below, the pH can be adjusted to 5 or less without any special adjustment, but when pH adjustment is necessary, A pH adjuster can also be used. Examples of the pH adjuster that can be used to lower the pH include citric acid, tartaric acid, lactic acid, and phosphoric acid. Moreover, as a pH adjuster for raising the pH to some extent, for example, 3.5 or more, monoethanolamine, triethanolamine, ammonia, sodium hydroxide, potassium hydroxide, sodium carbonate and the like can be used.

  The reducing agent in the first hair straightening agent is not particularly limited as long as it can reduce and cleave the bond of cystine in the hair. For example, thioglycolic acid, thioglycolate (ammonium thioglycolate, thioglycolate) Thioglycolic acid such as glycolic acid monoethanolamine); L-cysteine, L-cysteine salt (such as L-cysteine hydrochloride), DL-cysteine, DL-cysteine salt (such as DL-cysteine hydrochloride), N-acetyl -Cysteines such as L-cysteine;

  The compounding quantity of a reducing agent is 4.5 mass% or less in conversion of thioglycolic acid. When the blending amount of the reducing agent exceeds the above upper limit, hair damage suppression becomes insufficient, and the hair feel becomes poor. Moreover, even if the compounding quantity of a reducing agent exceeds the said upper limit, since the curly hair straightening effect is saturated, the increase in cost will be caused on the contrary. In addition, since the curly hair straightening effect may become small when there are too few compounding quantities of a reducing agent, it is preferable that it is 3.5 mass% or more converted into thioglycolic acid, for example.

  The blending amount of the reducing agent in the first hair straightening agent referred to in the present invention (the blended amount in terms of thioglycolic acid) is “Permanent Wave Approval Manufacturing (Import) Approval” issued by Permanent Wave Industrial Association. “(1) First agent” in “1. Cold-dissolved permanent wave solvent containing thioglycolic acid or its salts” in “[Attachment] Permanent Wave Agent Quality Standard” of “Standard” It is “content of reducing substance after acidic boiling (as thioglycolic acid) (%)” determined by the method defined in “(c) Reducing substance after acidic boiling”.

  Dithiodiglycolic acid or its salt (diammonium salt, diethanolamine salt, triethanolamine salt, etc.) in the first hair straightening agent is a reaction control that controls the reaction for reducing and cleaving cystine in the hair with a reducing agent It is a component that plays a role as an agent. Dithiodiglycolic acid or its salt may be used individually by 1 type, and may use 2 or more types together. Of these, diammonium dithiodiglycolate is preferable.

  In the first agent for straightening hair, the amount of dithiodiglycolic acid or a salt thereof is 1% by mass or more. If the blending amount of dithiodiglycolic acid or its salt is below the above lower limit, the hair feels straight after the straightening treatment, and for example, when the curly hair before the treatment is partially damaged, straightening is performed. It becomes difficult to suppress damage to the portion during processing. In addition, when there are too many compounding quantities of the dithiodiglycolic acid or its salt in the 1st agent for hair straightening, a hair straightening function may fall. Therefore, the blending amount of dithiodiglycolic acid or a salt thereof in the first agent for straightening hair is preferably 4% by mass or less, for example.

  The polyoxyethylene alkyl ether phosphate or its salt in the first agent for straightening hair and the phosphate other than polyoxyethylene alkyl ether phosphate are the hair of the first agent for straightening hair containing a reducing agent. It is a component that has the effect of increasing the permeability to the water and drawing out the action of the reducing agent. By blending these components, the first hair straightening agent of the present invention has a good curly hair straightening effect while reducing the pH and reducing the amount of reducing agent to suppress chemical damage to the hair. Secured. In addition, polyoxyethylene alkyl ether phosphates or salts thereof, and phosphate esters other than polyoxyethylene alkyl ether phosphates may be used during combing during straightening treatment or during physical treatment of hair with a hot hairstyling iron. It also has the effect of protecting hair and suppressing damage, and enhancing the feel of hair after treatment (moist feeling and softness).

  Polyoxyethylene alkyl ether phosphates or salts thereof include polyoxyethylene oleyl ether phosphate, polyoxyethylene lauryl ether phosphate, polyoxyethylene cetyl ether phosphate, polyoxyethylene octyl ether phosphate, polyoxyethylene ( 4) Decyl ether phosphate, polyoxyethylene alkylphenyl ether phosphate, polyoxyethylene alkyl ether sodium phosphate (polyoxyethylene oleyl ether sodium phosphate, polyoxyethylene lauryl ether sodium phosphate, polyoxyethylene cetyl ether phosphate Sodium, polyoxyethylene alkylphenyl ether sodium phosphate, etc.), polyoxyethylene alkylphenyl ether phosphate diethanol (Such as polyoxyethylene oleyl ether phosphate diethanolamine), polyoxyethylene alkyl ether phosphate triethanolamine (polyoxyethylene alkylphenyl ether phosphate triethanolamine, polyoxyethylene lauryl ether phosphate triethanolamine, etc.) These may be used alone or in combination of two or more. Among these, polyoxyethylene cetyl ether phosphorus has a particularly good effect on enhancing the permeability of the first hair straightening agent (that is, reducing agent) to hair and improving the feel of hair after treatment. Acid is preferred.

  The blending amount of the polyoxyethylene alkyl ether phosphate ester or salt thereof in the first agent for straightening hair is, for example, 0.5% by mass or more, more preferably 1% by mass or more, and 5% by mass or less. Preferably it is 3 mass% or less. If the blending amount of the polyoxyethylene alkyl ether phosphate ester or salt thereof is too small, the viscosity of the first agent for straightening hair may become low and separation may occur. If it is too much, the first agent for straightening hair. The viscosity of the resin may become too high and the operability may be reduced.

  Examples of phosphate esters other than polyoxyethylene alkyl ether phosphates include dimethyl phosphate, cetyl phosphate, dicetyl phosphate, trioleyl phosphate, tristearyl phosphate, and the like. You may use, and may use 2 or more types together. Among these, dicetyl phosphate is preferable because the first hair straightening agent containing a reducing agent has a particularly good effect on enhancing the penetrability into hair and the effect of improving the feel of hair after treatment.

  The blending amount of the phosphate ester other than the polyoxyethylene alkyl ether phosphate ester in the first agent for straightening hair is, for example, 0.3% by mass or more, more preferably 0.5% by mass or more, and 3% by mass. % Or less, more preferably 1.5% by mass or less. If the amount of the phosphate ester other than the polyoxyethylene alkyl ether phosphate is too small, the viscosity of the first agent for straightening hair may become low and separation may occur. The viscosity of one agent may become too high and the operability may be reduced.

  In addition to the above-mentioned components, the first agent for straightening hair can be blended with various additives that have been added to conventionally known hair straightening agents and other cosmetics for hair. . Examples of such additives include waxes, higher alcohols, silicones, hydrocarbons, humectants, surfactants (excluding polyoxyethylene alkyl ether phosphates or salts thereof), chelating agents, anti-inflammatory agents. And fragrances.

  Examples of waxes include beeswax, whale wax, lanolin, carnauba wax, and candelilla wax. Examples of higher alcohols include lauryl alcohol, cetanol, cetostearyl alcohol, stearyl alcohol, oleyl alcohol, behenyl alcohol, lanolin alcohol, octyldodecanol and the like. Examples of silicones include dimethyl silicone, highly polymerized dimethyl silicone, cyclic silicone, polyether-modified silicone, amino-modified silicone (aminoethylaminopropylsiloxane / dimethylsiloxane copolymer, aminoethylaminopropylmethylsiloxane / dimethylsiloxane copolymer). And an aminoethylaminopropylmethylpolysiloxane / dimethylpolysiloxane copolymer). Examples of the hydrocarbon include paraffin, liquid paraffin, light liquid isoparaffin, squalane, petrolatum, and microcrystalline wax. Examples of the humectant include glycerin, diglycerin, propylene glycol, 1,3-butylene glycol, dipropylene glycol, sodium pyrrolidonecarboxylate, hyaluronic acid, sorbitol, and highly polymerized polyethylene glycol.

  As the surfactant, various cationic surfactants, anionic surfactants, nonionic surfactants and amphoteric surfactants can be used. Examples of the cationic surfactant include alkyltrimethylammonium chloride such as lauryltrimethylammonium chloride and stearyltrimethylammonium chloride, distearyldimethylammonium chloride, cetyltrimethylammonium bromide, stearyltrimethylammonium bromide, stearyltrimethylammonium saccharin, ethyl Examples include lanolin sulfate fatty acid aminopropylethyldimethylammonium. Examples of the anionic surfactant include sodium lauryl sulfate, sodium polyoxyethylene lauryl ether sulfate, sodium stearoylmethyl taurate, triethanolamine dodecylbenzenesulfonate, sodium tetradecenesulfonate, and the like.

  Nonionic surfactants include, for example, polyoxyethylene alkyl ethers (polyoxyethylene stearyl ether, polyoxyethylene cetyl ether, polyoxyethylene lauryl ether, etc.), polyoxyethylene alkylphenyl ethers, polyoxyethylene polyoxy Propylene alkyl ether (polyoxyethylene polyoxypropylene cetyl ether, polyoxyethylene polyoxypropylene behenyl ether, polyoxyethylene polyoxypropylene 2-decyltetradecyl ether, polyoxyethylene polyoxypropylene butyl ether, polyoxyethylene polyoxypropylene water Lanolin, polyoxyethylene polyoxypropylene glycerin ether, etc.), polyoxyethylene polio Cypropylene glycol, glycerin fatty acid ester, polyglycerin fatty acid ester, sorbitan fatty acid ester (such as sorbitan monostearate), polyoxyethylene sorbitan monolaurate, polyoxyethylene sorbitan fatty acid ester, polyoxyalkylene benzyl ether, polyoxyethylene castor oil, Examples thereof include polyoxyethylene hydrogenated castor oil, sucrose fatty acid ester, alkyl polyglycoside, N-alkyldimethylamine oxide, polyoxyethylene propylene glycol fatty acid ester and the like. Examples of the amphoteric surfactant include cocamidopropyl betaine, lauryldimethylaminoacetic acid betaine, lauramidopropyl betaine, 2-alkyl-N-carboxymethyl-N-hydroxyethylimidazolinium betaine.

  Examples of the anti-inflammatory agent include dipotassium glycyrrhizinate and carbenoxolone disodium. Examples of the chelating agent include edetic acid, disodium edetate, citric acid, tartaric acid, salicylic acid, hydroxyethane diphosphonic acid, diethylenetriaminepentaacetic acid pentasodium, and the like.

  The first agent for straightening hair can be in the form of, for example, a cream, a lotion, or a gel, and water is the main dispersion medium. Note that some of the various components described above may be dissolved in water. Further, all of the dispersion medium may be water, and may contain an organic solvent such as a lower alcohol (ethanol, isopropanol, etc.). However, if the amount of the organic solvent in the dispersion medium is increased, the scalp and the like may be stimulated. Therefore, the content of the organic solvent in the dispersion medium is preferably, for example, 5% by mass or less.

  The second agent for straightening hair constituting the straightener for curly hair of the present invention together with the first straightener for straightening hair of the present invention comprises at least an oxidizing agent.

  As the oxidizing agent, an oxidizing agent used in conventionally known hair straightening agents can be used. Examples thereof include hydrogen peroxide and sodium bromate. In the case of hydrogen peroxide, the blending amount of the oxidizing agent in the second agent for straightening hair is, for example, 1% by mass or more, 2% by mass or less, more preferably 1.5% by mass or less. Is desirable. In the case of sodium bromate, for example, it is 5% by mass or more, 10% by mass or less, more preferably 8% by mass or less.

  In addition to the oxidizing agent, the second agent for straightening hair preferably contains a polyoxyalkyl ether phosphate or a salt thereof and a phosphate ester other than the polyoxyalkyl ether phosphate. . Specific examples of polyoxyalkyl ether phosphates or salts thereof include, for example, the compounds exemplified above as polyoxyalkyl ether phosphates or salts thereof according to the first agent for straightening hair. 1 type may be used independently and 2 or more types may be used together. Among these, polyoxyethylene cetyl ether phosphoric acid is preferable because it has a particularly good effect on improving the feel of hair after treatment.

  The blending amount of the polyoxyethylene alkyl ether phosphate ester or salt thereof in the second agent for straightening hair is, for example, 0.5% by mass or more, more preferably 1% by mass or more, and more preferably 5% by mass or less. Preferably it is 3 mass% or less.

  Specific examples of phosphate esters other than polyoxyethylene alkyl ether phosphate esters include, for example, the compounds exemplified above as phosphate esters other than polyoxyalkyl ether phosphate esters related to the first agent for straightening hair. These may be used alone or in combination of two or more. Among them, dicetyl phosphate is preferable because the hair feel-improving action after treatment is particularly good.

  The blending amount of the phosphate ester other than the polyoxyethylene alkyl ether phosphate ester in the second agent for straightening hair is, for example, 0.5% by mass or more, more preferably 1% by mass or more, and 5% by mass or less. More preferably, the content is 3% by mass or less.

  In addition to the above-mentioned components, the second agent for straightening hair can contain various additives added to conventionally known hair straightening agents and other cosmetics for hair. . Examples of such additives include fats and oils, higher alcohols, cationic polymers, humectants, surfactants (excluding polyoxyethylene alkyl ether phosphates or salts thereof), chelating agents, anti-inflammatory agents, antiseptics Agents, pH adjusters, ultraviolet absorbers, fragrances and the like. As for higher alcohols, moisturizers, surfactants, chelating agents, and anti-inflammatory agents, for example, the compounds exemplified above as additives for the first agent for straightening hair can be used.

  Examples of the oils and fats include castor oil, olive oil, camellia oil, macadamia nut oil, grape seed oil, mink oil, egg yolk oil, cocoa butter, coconut butter, palm oil, molasses, avocado oil, and shea fat. Examples of the cationic polymer include acrylamide / acrylic acid / dimethyldiallylammonium chloride copolymer. Examples of the preservative include sodium benzoate, benzalkonium chloride, sorbic acid, potassium sorbate, methyl paraoxybenzoate, ethyl paraoxybenzoate, propyl paraoxybenzoate, butyl paraoxybenzoate, and phenoxyethanol. Examples of the pH adjuster include phosphoric acid and disodium hydrogen phosphate. Examples of the ultraviolet absorber include hydroxymethoxybenzophenone sulfonic acid.

  The second agent for straightening hair can be in the form of, for example, a cream, a lotion, or a gel, and water is the main dispersion medium. Note that some of the various components described above may be dissolved in water. Further, all of the dispersion medium may be water, and may contain an organic solvent such as a lower alcohol (ethanol, isopropanol, etc.). However, if the amount of the organic solvent in the dispersion medium is increased, the scalp and the like may be stimulated. Therefore, the content of the organic solvent in the dispersion medium is preferably, for example, 5% by mass or less.

  The curly hair straightening agent of the present invention is composed of the first curly hair straightening agent of the present invention and the second curly hair straightening agent. The curly hair straightening treatment with the curly hair straightening agent. As will be described later, first, after applying the first agent for straightening hair to the hair, the hair is straightened, and then the second agent for straightening hair is applied to the hair. The Therefore, the product form of the above-mentioned hair straightening agent is mixed before the hair straightening treatment, for example, the first agent for straightening hair and the second agent for straightening hair are filled in separate containers. The form which does not do is taken.

<Hair straightening method>
As a method for straightening hair using the hair straightening agent of the present invention, after applying the first hair straightening agent to the hair, the hair is straightened and straightened, and then the hair is washed. Then, the method of applying the second agent for straightening hair after removing the first agent for straightening hair and drying it can be employed. And after application | coating of the 2nd agent for curly hair correction, hair is wash | cleaned and dried, and a process is complete | finished. In addition, after apply | coating the 1st agent for hair straightening, it is preferable to wash | clean hair and wash away the 1st agent for hair straightening applied and to dry hair and to correct.

  As a method for straightening hair after applying the first agent for straightening hair, for example, hair is straightened by combing or the like, and the hair is straightened and further heated with a dryer. The method can be adopted. In the present invention, since the component of the first agent for straightening hair can be protected from heat and other physical impacts applied during straightening, such straightening is possible. Hair damage during the treatment is suppressed.

  Moreover, in the present invention, as described above, the blending component of the first agent for straightening hair can protect the hair from heat and other physical impacts applied at the time of straightening hair, After the above correction, it is also possible to perform further correction using a high-temperature hair-styling iron. By adopting such a correction method, the curly hair correction rate can be further improved.

  When using a high-temperature hairstyling iron, the surface temperature should be 60 ° C. or higher, more preferably 80 ° C. or higher, 220 ° C. or lower, more preferably 200 ° C. or lower, more preferably 180 ° C. or lower. Is desirable. And in order to straighten hair using the high-temperature hair-styling iron whose surface temperature is adjusted in this way, for example, after applying the first agent for curly hair straightening, the straightened hair straightened is washed. After the first agent for straightening hair is removed and preferably dried, further correction is performed with a high-temperature hair-styling iron. As the straightening treatment using the high-temperature hair-styling iron, for example, a method of taking a hair bundle, sandwiching the hair from the root with the iron, and sequentially processing in the direction of the hair tip is preferable. The time for sandwiching the hair with the iron is preferably 2 seconds or less, and it is preferable not to treat the same portion twice. When the treatment is performed for more than 2 seconds, protein denaturation of the hair due to heat occurs, which may lead to hair damage.

  The high-temperature hairstyling iron is not particularly limited as long as the surface can be adjusted to the above temperature and has a flat surface. For example, “thermal effect iron CR (trade name)”, “thermal effect iron FS” (Product name) "and" Thermal effect iron G short (Product name) "(both manufactured by Milbon) are preferably used.

  Hereinafter, the present invention will be described in detail based on examples. However, the following examples are not intended to limit the present invention, and all modifications made without departing from the spirit of the preceding and following descriptions are included in the technical scope of the present invention. In the following examples, “%” means “mass%”. In addition, as the blending amount of the first agent for straightening hair and the second agent for straightening hair, the blending amount of each component is shown in% so that it becomes 100% as a whole. The display is omitted and only the numerical value indicating the blending amount is displayed.

Examples 1-10 and Comparative Examples 1-7
As shown in Tables 4 and 5, the first hair straightening agent (Tables 1 and 2) and the second hair straightening agent (Table 3) prepared according to the formulations shown in Tables 1 to 3 are used. An orthodontic agent was constructed. Using these hair straightening agents, the following hair bundles were subjected to hair straightening treatment and evaluated for their characteristics.

<Hair straightening treatment>
A curly hair collected from the same person, a hair bundle having a length of 22 cm (measured in a natural state without stretching) and a weight of 1.5 g was prepared. After washing and drying, 3.0 g of the first hair straightening agent according to the hair straightening agent of Examples 1 to 10 or Comparative Examples 1 to 7 is applied and the curly hair is straightened. After standing at room temperature for 20 minutes, it was washed with water and dried with a dryer. 3.0 g of the second hair straightening agent according to the hair straightening agent of Examples 1 to 10 or Comparative Examples 1 to 7 is applied to the dried hair bundle, left at room temperature for 10 minutes, and then washed with water. The hair was straightened for 24 hours to complete the curly hair straightening process. The effect of straightening hair, the moist feeling of hair and the softness of the hair after the hair straightening treatment were evaluated according to the following criteria. The results are also shown in Tables 4 and 5.

<Hair straightening effect>
One end of the hair bundle after the curly hair straightening treatment was fixed to the panel and hung, the total length was measured, and the curly hair straightening rate was determined by the following formula.
Hair straightening rate = 100 × (A−B) / (C−B)
A: Full length (mm) of hair bundle after curly hair straightening treatment
B: Total length (mm) of the hair bundle before curly hair straightening in the natural state
C: Total length (mm) in a state where the hair bundle before straightening treatment is straightened

<Moist hair>
About the moist feeling of the hair after a curly hair correction process, sensory evaluation by 20 professional panelists was implemented according to the following reference | standard. ◎ and ○ are acceptable.
A: 16 or more of 20 panelists evaluated it as excellent.
○: Among 20 panelists, 12 or more and 15 or less were evaluated as excellent.
Δ: Among 20 panelists, 8 or more and 11 or less were evaluated as excellent.
X: It evaluated that 7 or less out of 20 panelists were excellent.

<Softness of hair>
For the softness of the hair after the straightening treatment, sensory evaluation by 20 professional panelists was performed according to the following criteria. ◎ and ○ are acceptable.
A: 16 or more of 20 panelists evaluated it as excellent.
○: Of 20 panelists, 12 or more and 15 or less were evaluated as excellent.
Δ: Of 20 panelists, 8 or more and 11 or less were evaluated as excellent.
X: It evaluated that 7 or less out of 20 panelists were excellent.

  The pH in the first agent for straightening hair shown in Table 1 and Table 2 was adjusted by blending monoethanolamine as a pH adjuster. Moreover, pH in the 2nd agent for curly hair correction shown in Table 3 was adjusted by mix | blending disodium hydrogenphosphate as a pH adjuster. “To 100 in total” in the column of purified water in Tables 1 to 3 refers to the total amount of each component other than purified water constituting the first agent for straightening hair or the second agent for straightening hair. It means that the amount of water was added to reach 100%.

  As can be seen from Tables 4 and 5, the hair treated with the hair straightening agents of Examples 1 to 10 has a high curly hair straightening rate and is well corrected. Moreover, when the hair after the hair straightening treatment is damaged by the treatment, the moist feeling and softness are impaired, but the hair was treated with the hair straightening agent of Examples 1 to 10. In hair, moist feeling and softness are also good, and damage during curly hair straightening treatment is suppressed. On the other hand, in the hair processed using the hair straightening agent of Comparative Examples 1 to 7, the curly hair correction rate is low and the correction is insufficient, or the moist feeling and softness are insufficient and the hair is straightened. Damaged by processing.

Claims (9)

  At least 4.5% by mass or less of the reducing agent in terms of thioglycolic acid, and 1% by mass or more of dithiodiglycolic acid or a salt thereof are blended, and polyoxyethylene alkyl ether phosphate or a salt thereof, and poly A first agent for straightening hair, characterized in that a phosphate ester other than oxyethylene alkyl ether phosphate ester is blended and has a pH of 5 or less.   The first agent for straightening hair according to claim 1, wherein the polyoxyethylene alkyl ether phosphate or a salt thereof is polyoxyethylene cetyl ether phosphate.   The first agent for straightening hair according to claim 1 or 2, wherein the phosphate other than the polyoxyethylene alkyl ether phosphate is dicetyl phosphate. The first agent for straightening hair according to any one of claims 1 to 3,
A curly hair straightening agent comprising at least a second hair straightening agent containing an oxidizing agent.   5. The curly hair according to claim 4, wherein the second agent for straightening hair further contains a polyoxyethylene alkyl ether phosphate ester or a salt thereof, and a phosphate ester other than the polyoxyethylene alkyl ether phosphate ester. Hair straightener.   The agent for straightening hair according to claim 5, wherein the polyoxyethylene alkyl ether phosphate or a salt thereof in the second agent for straightening hair is polyoxyethylene cetyl ether phosphate.   The hair straightening agent according to claim 5 or 6, wherein the phosphate ester other than the polyoxyethylene alkyl ether phosphate ester in the second hair straightening agent is dicetyl phosphate. A method for straightening curly hair using the curly hair straightening agent according to any one of claims 4 to 7,
After applying the first curly hair straightening agent to the curly hair, the curly hair is straightened, the curly hair after the straightening is washed to remove the first curly hair straightening agent, and then the second curly hair straightening agent A method for straightening curly hair, characterized in that the hair is applied to the curly hair for processing.   9. The method according to claim 8, wherein after the first agent for straightening hair is washed and removed, the curly hair before application of the second agent for straightening hair is further corrected using a high-temperature hairstyling iron having a surface temperature of 60 to 220 ° C. The straightening treatment method of the described curly hair.