Hair treatment agent, hair deformation agent set, and hair deformation treatment method

Abstract

To provide a hair treatment agent, a hair transformation agent set, and a hair transformation treatment method, which have excellent hair-shaping ability such as straightening, curling, or permanent wave treatment while suppressing damage to hair, and can finish the hair with excellent finger combability, luster, and moist texture.SOLUTION: Provided is a hair treatment agent containing at least one reducing agent (A) selected from ammonium thioglycolate, thioglycerin, and thiolactic acid, the reducing agent (A) being in the range of 2.0 to 10.0 mass% in terms of thioglycolic acid, and the pH being 2 to 7.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to a hair treatment agent, a hair shaping agent set, and a hair shaping method.

Background Art

[0002] Conventionally, in hair shaping treatments such as hair straightening, curling, or permanent waving, the cystine bonds in the hair are reduced with a reducing agent to form a desired shape, and then fixed again. In particular, in hair straightening, due to the uneven arrangement of the cortex inside the hair of curly hair, it is necessary to sufficiently penetrate a high-concentration reducing agent into the hair for reduction. However, a problem has been that a high-concentration reducing agent causes significant damage to the hair. Therefore, the development of a new method for suppressing damage has been underway.

[0003] As a technique for suppressing damage in permanent waving, Patent Document 1 discloses a hair treatment agent composition that contains thioglycolic acid, an organic acid and / or phosphoric acid, and an organic acid salt and / or phosphate salt, and is acidic. Further, Patent Document 2 discloses a hair shaping treatment agent for straightening or transforming the hair shape into a wave shape, which includes a first agent containing a reducing agent with a pH of less than 7.0, an intermediate treatment agent with a higher pH than the first agent and a pH of 10.5 or less, and a second agent containing an oxidizing agent.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the technology described in Patent Document 1 did not provide sufficient straightening and curl-forming capabilities for curly hair. This was thought to be because the hair treatment composition in Patent Document 1 contains only acidic thioglycolic acid as a reducing agent. While it penetrates into the hair shaft, it was thought that the reduction of both the inside and outside of the hair was insufficient. In other words, the composition had weak reducing power, and even if it did reduce the hair, the reduction was uneven, resulting in insufficient straightening of the curly hair. Furthermore, the fact that acidic thioglycolic acid has less reducing power compared to alkaline thioglycolic acid was also thought to be a reason why it was difficult to straighten curly hair.

[0006] In the technology described in Patent Document 2, since the intermediate treatment agent does not contain a reducing agent, it was thought that only the inside of the hair was reduced, and the outside of the hair was hardly reduced at all. This resulted in an uneven reduction of the hair, and it was thought that the curly hair was not straightened sufficiently. Furthermore, the curl-forming ability was not of satisfactory quality.

[0007] Until now, there have been no hair treatment agents, hair modification agent sets, or hair modification treatment methods that minimize damage by using an acidic reducing agent to penetrate and retain the reducing agent inside the hair, and then simultaneously reducing both the inside and outside of the hair with an alkaline reducing agent.

[0008] Therefore, the object of the present invention is to provide a hair treatment agent, a hair modification agent set, and a hair modification treatment method that can reduce damage to the hair while providing excellent hair-shaping capabilities such as straightening, curling, or permanent wave treatment, as well as resulting in hair with excellent manageability, shine, and a moist texture. [Means for solving the problem]

[0009] The inventors diligently studied to solve the above problems. As a result, they found that a hair treatment agent, a hair modification agent set, and a hair modification treatment method having the following configuration can solve the above problems, and thus completed the present invention.

[0010] The present invention includes, for example, the following [1] to [8]. [1] A hair treatment agent comprising at least one reducing agent (A) selected from ammonium thioglycolate, thioglycerin, and thiolactate, wherein the reducing agent (A) is in the range of 2.0 to 10.0% by mass in terms of thioglycolic acid, and the pH is 2 to 7. [2] The hair treatment agent according to [1], comprising 0.2 to 1.0% by mass of diethylenetriaminepentaacetate (B). [3] A hair treatment agent according to [1] or [2], comprising 0.2 to 2.0% by mass of steartrimonium chloride (C). [4] A hair treatment agent as described in any of [1] to [3], which is applied to the hair before straightening, curling, or permanent wave treatment. A hair modification agent set comprising a hair treatment agent described in any of [5][1] to [3], and a first hair modification agent containing a keratin fiber reducing substance in an amount of 2.0 to 11.0% by mass in terms of thioglycolic acid, and having a pH of 7 to 10. A hair modification treatment method comprising the steps of: (I) applying a hair treatment agent described in any of [6][1] to [3] to the hair; (II) applying a first hair modification agent to the hair after step (I), which contains a keratin fiber reducing substance in an amount of 2.0 to 11.0% by mass in terms of thioglycolic acid and has a pH of 7 to 10; and (III) applying a second hair modification agent containing an oxidizing agent to the hair after step (II). [7] The hair deformation treatment method according to [6], wherein step (Ia) of washing the hair is performed after step (I) and before step (II). [8] A hair deformation treatment method according to [6] or [7], wherein step (III) is performed on hair that has undergone step (II-a) of heating the hair after step (II). [Effects of the Invention]

[0011] The present invention provides a hair treatment agent, a hair modification agent set, and a hair modification treatment method that can minimize damage to the hair while providing excellent hair-shaping capabilities such as straightening, curling, or permanent wave treatment, as well as resulting in hair with excellent manageability, shine, and a moist texture. [Modes for carrying out the invention]

[0012] Next, the hair treatment agent, hair modification agent set, and hair modification treatment method of the present invention will be described in detail.

[0013] <Hair treatment product> The hair treatment agent of the present invention comprises at least one reducing agent (A) selected from ammonium thioglycolate, thioglycerin, and thiolactate, wherein the reducing agent (A) is in the range of 2.0 to 10.0% by mass in terms of thioglycolic acid, and the pH is 2 to 7. The content of each component in this invention is given when the hair treatment agent is considered to be 100% by mass.

[0014] The hair treatment agent of the present invention is preferably applied to the hair before straightening, curling, or permanent wave treatment.

[0015] By applying the hair treatment agent of the present invention to the hair before straightening, curling, or permanent wave treatment, it is possible to straighten curly hair, hair that has been curled or bent due to permanent wave treatment, etc. Furthermore, by applying the hair treatment agent of the present invention to the hair before curling or permanent wave treatment, it also provides excellent curl-forming ability.

[0016] <Reducing agent (A)> The hair treatment agent of the present invention comprises at least one reducing agent (A) selected from ammonium thioglycolate, thioglycerin, and thiolactate, wherein the reducing agent (A) is in the range of 2.0 to 10.0% by mass, preferably 3.0 to 9.0% by mass, more preferably 4.0 to 8.0% by mass, and most preferably 4.0 to 5.0% by mass, in terms of thioglycolic acid.

[0017] When the reducing agent (A) is within the above range, damage to the hair can be suppressed and curly hair can be made straight. Further, by applying it to the hair before curling treatment or permanent wave treatment and using it, it is excellent in curl forming power.

[0018] When the reducing agent (A) is less than the lower limit amount, the hair curl does not stretch and almost no curl tends to be formed. When the reducing agent (A) is more than the upper limit amount, there is damage to the hair, the finger combability becomes very poor, and the finished texture tends to be rough.

[0019] As the reducing agent (A) in the present invention, at least one selected from ammonium thioglycolate, thioglycerol, and thiolactate is preferable, at least one compound selected from ammonium thioglycolate and thioglycerol is more preferable, and from the viewpoint of stretching the curl, ammonium thioglycolate is most preferable, and from the viewpoint of shortening the treatment time, thioglycerol is most preferable.

[0020] In the present invention, examples of the thiolactate include ammonium thiolactate, monoethanolamine thiolactate, and isopropanolamine thiolactate. Among these, ammonium thiolactate is preferable as the thiolactate.

[0021] In the examples of the present invention, thioglycerol is also referred to as 3-mercapto-1,2-propanediol, and ammonium thiolactate is also referred to as ammonium 2-mercaptopropionate. The reducing agent (A) may be used alone or in combination of two or more.

[0022] <ph> The hair treatment agent of the present invention has a pH of 2 to 7, preferably 3 to 6, and more preferably 4 to 5. When the pH is within the aforementioned range, it is possible to straighten hair that is curved due to frizz while minimizing damage to the hair. It also exhibits excellent curl-forming ability through curling or permanent wave treatments. In particular, the hair treatment agent of the present invention is more preferable because, with a pH of 4 to 5, it is possible to achieve a balance between the strength to straighten hair that is curved due to frizz, strong curl-forming ability, and reduced damage to the hair, and there is almost no odor during treatment.

[0023] In the present invention, when ammonium thioglycolate is used as the reducing agent (A), the pH is preferably 4.8 to 5.5. This is preferable because it allows for a balance between the strength to straighten curly hair, strong curl-forming ability, and reduced damage to the hair, and there is almost no odor during the treatment.

[0024] When the pH is below 2, hair is more damaged and the skin, especially the scalp, tends to become more irritated. When the pH is above 7, curls are straightened effectively, but hair is more damaged and tends to lose its shine.

[0025] The inventors have been investigating how to achieve both improved straightening of curved hair or strong curl formation, and reduced damage to the hair. Through this investigation, they discovered that when the pH is within the range of 2 to 7, the penetration of the reducing agent into the hair increases, and they succeeded in developing a hair treatment agent that excels in straightening of curved hair or strong curl formation while minimizing damage to the hair.

[0026] When setting the pH of the hair treatment agent of the present invention to the above pH, the pH can be adjusted as needed. The pH of the hair treatment agent of the present invention can be adjusted by appropriately blending, for example, organic acids, organic acid salts, inorganic acids, inorganic acid salts, etc.

[0027] pH adjustment can be specifically carried out by appropriately blending phosphoric acid, sodium hydroxide, triethanolamine, arginine, and ammonia. Among these, pH adjustment is preferably carried out by appropriately blending phosphoric acid and ammonia due to their excellent texture and stability. pH adjustment may be performed using a single component or by combining two or more components.

[0028] <Diethylenetriaminepentaacetate (B)> The hair treatment agent of the present invention preferably contains 0.2 to 1.0% by mass, more preferably 0.3 to 0.8% by mass, and most preferably 0.4 to 0.6% by mass of diethylenetriaminepentaacetate (B). When diethylenetriaminepentaacetate (B) is within the aforementioned range, it is preferable because it exhibits excellent stability over time.

[0029] In the present invention, an example of diethylenetriaminepentaacetate (B) is pentasodium diethylenetriaminepentaacetate. It is preferable that diethylenetriaminepentaacetate (B) is diethylenetriaminepentaacetate pentasodium. As diethylenetriaminepentaacetate (B), for example, Kirest P-SD (manufactured by Chubu Kirest Co., Ltd.) can be used. Kirest P-SD contains 40% pentasodium diethylenetriaminepentaacetate and 60% water. Diethylenetriaminepentaacetate (B) may be used alone or in combination of two or more types.

[0030] <Steartrimonium Chloride (C)> The hair treatment agent of the present invention preferably contains 0.2 to 2.0% by mass, more preferably 0.3 to 1.8% by mass, and most preferably 0.4 to 1.5% by mass of steartrimonium chloride (C).

[0031] When steartrimonium chloride (C) is within the aforementioned range, it is preferable because it results in smoother, more manageable hair and a more moisturized texture. For example, steartrimonium chloride (C) can be used, such as Catinal STC-70ET (manufactured by Toho Chemical Co., Ltd.). Catinal STC-70ET contains 70% steartrimonium chloride, 24% ethanol, and 6% water.

[0032] Other ingredients The hair treatment agent of the present invention typically contains water. The water content is not particularly limited and can be appropriately prepared and used depending on the purpose of use. Specifically, the water can be tap water, deionized water, distilled water, purified water, or natural water, and sterilized water is preferred.

[0033] The hair treatment agent of the present invention may contain any components other than those mentioned above, as long as they do not impair the effects of the present invention. Examples of optional components include pH adjusters, humectants, herbal medicines, chelating agents, preservatives, antioxidants, cooling agents, antistatic agents, vitamins, proteins, fragrances, antibacterial agents, thickeners, emulsifiers, emulsifying stabilizers, surfactants, higher alcohols, silicones, oils, solvents, and dyes. In the hair treatment agent of the present invention, ammonia and phosphoric acid can be used as optional components, specifically as pH adjusters; and ethanol can be used as a solvent.

[0034] 《Manufacturing method, etc.》 The hair treatment agent of the present invention can be manufactured by stirring, mixing, heating, dissolving, dispersing, etc., using the above-mentioned components in the above-mentioned amounts, for example, by known methods, and the manufacturing method is not particularly limited. The manufacturing method may be carried out under heating conditions in order to uniformly mix each component. When manufacturing under heating conditions, for example, a temperature of 75 to 85°C can be given.

[0035] Dosage Form The hair treatment agent of the present invention can be in liquid, cream, or gel form, and from the viewpoint of ease of use, a liquid form is preferred. A liquid form is preferable because, after shampooing at a hair salon, the hair treatment agent of the present invention can be applied to the hair at the shampoo station, left on, and then rinsed. The hair treatment agent of the present invention preferably has an appearance of milky white. The hair treatment agent of the present invention is liquid and more preferably milky white.

[0036] 《How to use》 The hair treatment agent of the present invention can be used by applying it to the hair. The hair treatment agent of the present invention is preferably used by applying it to hair after washing the hair with a hair cleansing agent such as shampoo. The hair treatment agent of the present invention can be applied and used on hair that is dry, wet, or damp. However, it is preferable to apply the hair treatment agent to damp hair, such as after towel-drying, as this enhances the penetration effect of the hair treatment agent into the hair. Furthermore, it is preferable to apply the hair to damp hair as it is easier to comb.

[0037] The hair treatment agent of the present invention is not particularly limited in its use, but it is preferably applied to the hair before straightening, curling, or permanent wave treatment, and is more preferably applied to the hair before straightening, as it is excellent at straightening curly hair. The hair treatment agent of the present invention may be applied to the hair, rinsed off, or left on before performing hair straightening, curling, or permanent wave treatment.

[0038] The inventors have discovered that by allowing a reducing agent contained in an acidic hair treatment agent to penetrate the hair shaft, leaving the penetrated reducing agent inside the hair shaft, and then reducing it with an alkaline reducing agent, the hair shaft can be thoroughly reduced while the hair shaft is reduced while minimizing damage to the hair. This results in superior hair-forming capabilities for treatments such as hair straightening, curling, and permanent wave treatments.

[0039] The hair treatment agent of the present invention is preferable to apply to the hair, rinse it off, and then perform hair straightening, curling, or permanent wave treatment, in order to prevent excessive reduction of the hair's exterior by a subsequent alkaline reducing agent while keeping the reducing agent that has penetrated into the hair's interior, thereby minimizing damage.

[0040] <Hair Modification Agent Set> The hair modification agent set of the present invention comprises the hair treatment agent of the present invention described above, and a first hair modification agent containing a keratin fiber reducing substance in an amount of 2.0 to 11.0% by mass in terms of thioglycolic acid, and having a pH of 7 to 10.

[0041] In the hair modification agent set of the present invention, the hair treatment agent of the present invention comprises at least one reducing agent (A) selected from ammonium thioglycolate, thioglycerin, and thiolactate, wherein the reducing agent (A) is in the range of 2.0 to 10.0% by mass, preferably 3.0 to 9.0% by mass, and more preferably 4.0 to 8.0% by mass, in terms of thioglycolic acid.

[0042] In the hair modification agent set of the present invention, the hair treatment agent of the present invention has a pH of 2 to 7, preferably 3 to 6, and more preferably 4 to 5. When ammonium thioglycolate is used as the reducing agent (A), the hair treatment agent of the present invention preferably has a pH of 4.8 to 5.5.

[0043] In the hair modification agent set of the present invention, the keratin fiber reducing substance is in the range of 2 to 11% by mass, preferably 3 to 11% by mass, and more preferably 4 to 11% by mass, in terms of thioglycolic acid.

[0044] In the hair modification agent set of the present invention, the keratin fiber reducing substance is not particularly limited as long as it is a compound that has a reducing effect on keratin, which is a structural protein of hair, but examples include thioglycolic acid and its salts; thioglycerin and its salts; cysteamine and its salts; cysteine ​​and its salts; thiolactic acid and its salts; sulfite and its salts; and butyrolactone thiol.

[0045] Examples of keratin fiber reducing substances include thioglycolic acid, ammonium thioglycolate, thioglycerin, cysteamine, cysteamine hydrochloride, cysteine, cysteine ​​hydrochloride, thiolactic acid, and sodium sulfite. Among these, ammonium thioglycolate is preferred because it provides good straightening of curls.

[0046] In the hair modification agent set of the present invention, the first hair modification agent has a pH of preferably 7 to 9.5, more preferably 8 to 9.5. In the hair modification agent set of the present invention, it is preferable that the thioglycolic acid equivalent value of the hair treatment agent of the present invention is set lower than that of the first hair modification agent. It is preferable that the thioglycolic acid equivalent value of the hair treatment agent is set lower than that of the first hair modification agent because it tends to be excellent in straightening curved hair or forming curls, while also being excellent in suppressing damage to the hair.

[0047] <Hair deformation treatment method> The hair deformation treatment method of the present invention comprises the steps of (I) applying the hair treatment agent of the present invention described above to the hair, (II) applying the first hair deformation agent described above to the hair after step (I), and (III) applying the second hair deformation agent containing an oxidizing agent to the hair after step (II).

[0048] In the hair deformation treatment method of the present invention, it is preferable to perform step (Ia), in which the hair is washed, after step (I) and before step (II). The inventors believe the reason for this is as follows.

[0049] First, in step (I), the reducing agent contained in the hair treatment agent of the present invention is allowed to penetrate into the hair and remain inside the hair. Next, by performing step (Ia) of washing the hair, any excess hair treatment agent adhering to the outside or surface of the hair can be washed away. Therefore, in the following step (II), when the hair is reduced with the alkaline reducing agent contained in the first hair modification agent, the inside of the hair can be thoroughly reduced, while the outside of the hair can be reduced without excessive reduction. In other words, it is possible to straighten curved hair while minimizing damage to the hair, and it is also preferable because it has excellent curl-forming ability through curling treatment or permanent wave treatment.

[0050] In the hair deformation treatment method of the present invention, it is preferable to perform step (III) on hair that has undergone step (II) above, followed by step (II-a) of heating the hair. Step (I) is preferably a step of applying 50 to 60 g of the hair treatment agent of the present invention to 100 g of hair. Furthermore, from the viewpoint of enhancing the penetration of the reducing agent into the hair, it is more preferable to leave the hair treatment agent on the hair at room temperature (18 to 28°C) for 1 to 8 minutes, preferably 2 to 4 minutes. Furthermore, from the viewpoint of suppressing damage to the hair and shortening the time, it is preferable not to leave it on at room temperature (18 to 28°C) for more than 10 minutes.

[0051] It is preferable that the hair treatment agent used in step (I) of the present invention has a lower thioglycolic acid equivalent value than the first hair modification agent used in step (II). It is preferable that the thioglycolic acid equivalent value of the hair treatment agent is set lower than that of the first hair modification agent because it tends to be excellent in straightening curved hair or forming curls, while also being excellent in suppressing damage to the hair.

[0052] Step (Ia) is more preferably a step of rinsing the hair with water. Step (II-a) is preferably a step of heating the hair using a hair iron. In step (II-a), the temperature of the hair iron is preferably 170 to 210°C, more preferably 178 to 182°C. As the hair iron, for example, the ADST Premium DS2 (HAKKO Corporation) can be used.

[0053] In step (II-a), a preferred method for heating the hair is to apply the hair iron to the dry hair from the roots to the ends for 2 to 15 seconds, preferably 1 to 10 times, more preferably 2 to 4 times. The process of heating hair by bringing a hair iron into contact with it is also referred to as "iron-through."

[0054] In the hair deformation treatment method of the present invention, the second hair deformation agent containing an oxidizing agent used in step (III) is not particularly limited, and conventionally known agents, as well as agents used for hair straightening, curling, or permanent wave treatments, can be used as is. Examples of oxidizing agents included in the second hair modification agent include bromate salts and hydrogen peroxide. [Examples]

[0055] The present invention will now be described in more detail with reference to examples, but the present invention is not limited thereto.

[0056] <Examples 1-48, Comparative Examples 1-12> In the examples and comparative examples, commercially available products listed in Table 1 below were used. Furthermore, in the raw materials listed in Table 1, "1-thioglycerol SPG" contains 98% 3-mercapto-1,2-propanediol.

[0057] [Table 1]

[0058] Each hair treatment agent in the examples and comparative examples was prepared by mixing the components according to the formulations shown in Tables 3 to 14, and these were used as samples for the sensory evaluations in (1) to (8). In the sensory evaluations of (1), (2), and (4)-(8), wavy human hair bundles were damaged under the conditions described below, the hair treatment agent of the sample was applied, and then the hair was straightened to create a straight design for evaluation. In the sensory evaluation of (3), wavy human hair bundles were damaged under the conditions described below, the hair treatment agent of the sample was applied, and then a permanent wave treatment was performed to form curls for evaluation.

[0059] The results of the sensory evaluations for (1) to (8) are shown in Tables 3 to 14. The numerical values ​​in the tables represent the mass percentage of each component, with the hair treatment agent being 100% by mass. Values ​​marked with an asterisk (*) in the tables indicate the thioglycolic acid equivalent value, and if a pH is listed in the 89% phosphoric acid column, it indicates that 89% phosphoric acid was added to achieve the indicated pH.

[0060] [Damage Processing] Wavy hair strands obtained from a hair salon were washed with 3g of Sherpa Design Supplement D-1 Shampoo (manufactured by Arimino Co., Ltd.), rinsed with water, and towel-dried. Afterward, the following damage treatments were performed to replicate the damage to the hair of an average person.

[0061] Hair bundles (approximately 20 cm, 10 g of wavy human hair: obtained from a hair salon) were immersed in a damage treatment aqueous solution prepared according to the proportions listed in Table 2 at 60°C for 10 minutes to induce damage. Afterwards, the hair bundles were removed from the damage treatment aqueous solution, rinsed with water, and dried.

[0062] [Table 2]

[0063] [Pre-treatment] Ten grams of damaged hair were rinsed with water and towel-dried. Then, 20 grams of the hair treatment agent sample was applied, left at 25°C for 3 minutes, and then rinsed with water. The odor of the hair treatment agent applied to the sample was evaluated according to (7).

[0064] [Hair straightening] After performing the above pretreatment, 20g of the first straightening agent (Qualine TC 250: manufactured by Arimino Co., Ltd.: thioglycolic acid equivalent value 10.7%, pH 8.9) was applied to 10g of rinsed hair strands, left at 25°C for 15 minutes, then rinsed with water and dried with a hairdryer.

[0065] Next, using a hair iron (ADST Premium DS2: manufactured by Hakko Co., Ltd.) set to 180℃, the hair was passed through the iron three times for 10 seconds each time, from the roots to the ends, to create a straight style.

[0066] 10g of straightened hair strands were treated with 20g of the second straightening agent (Qualine OX 2nd agent: manufactured by Arimino Co., Ltd.), left at 25°C for 15 minutes, then rinsed with water and dried with a hairdryer. The finished hair bundles were evaluated using (1), (2), (4)-(6), and (8).

[0067] [Permanent wave treatment] After the above pretreatment, 20g of hair modification agent 1 (Cosme Curl Prism Plus H: manufactured by Arimino Co., Ltd.: 5.0% thioglycolic acid equivalent, pH 8.2) was applied to 10g of rinsed hair bundles, and the hair bundles were wrapped around a New Ever Rod F-type 15 (manufactured by Evermade Co., Ltd.) and left at 25°C for 15 minutes. Then, 20g of hair modification agent 2 (Prism Plus After Lotion: manufactured by Arimino Co., Ltd.) was applied to the hair bundles, left at 25°C for 15 minutes, rinsed with water, and dried with a hairdryer. The finished hair bundles were evaluated according to (3).

[0068] [Evaluation Criteria] The sensory evaluations for (1) to (8) were conducted by 10 professional panelists (hairdressers), each giving their own evaluation. The evaluation was based on the average score of the 10 people according to the evaluation criteria listed below for each item, and the evaluation was made as follows based on the average score. ◎: The average score from the 10 expert panelists (hairdressers) is 3.5 points or higher. ○: The average score from the evaluations of the 10 professional panelists (hairdressers) is between 2.5 and 3.5 points. △: The average score from the 10 professional panelists (hairdressers) is between 1.5 and 2.5 points. ×: The average score from the 10 professional panelists (hairdressers) is less than 1.5 points.

[0069] (1) Straightening out curls The finished hair strands were visually evaluated to determine whether the curls had been straightened and the curved hairs had become straight. 4 points: The curls are straightened out nicely. 3 points: The curl has straightened out. Points 2: The curl hasn't straightened out, and the waves remain. 1 point: The curl hasn't straightened out at all.

[0070] (2) Damage to hair The damage to the finished hair strands was evaluated by touch. 4 points: Compared to the control group (without pretreatment), it has a significantly smoother feel. 3 points: Compared to the control group (without pretreatment), it has better texture. Point 2: Compared to the control group (without pretreatment), it is less smooth to the touch. Point 1: Compared to the control group (without pretreatment), the texture is extremely rough.

[0071] (3) Curl-forming ability (ridge) The strength of the curl in the finished hair strands was evaluated visually and by touch. The peaks of hair that have curled and formed an S-shape are called ridges, and these ridges serve as a standard for indicating the curl-forming ability of hair treatment products. The higher the curl-forming power, the more three-dimensional and clearly defined the curl will be. Conversely, as the curl-forming power decreases, the curl becomes loose and lacks definition. If the curl-forming power decreases even further, no curl will be formed at all. 4 points: Compared to the control group (without pretreatment), the curls have more elasticity and firmness, and a very clearly defined ridge is formed. Points 3: Compared to the control group (without pretreatment), the curls have more elasticity and firmness, and a clearly defined ridge is formed. Points 2: Compared to the control group (without pretreatment), the curls have elasticity and firmness, but are at a similar level. Point 1: Compared to the control group (without pretreatment), the curls lacked elasticity and firmness, and hardly any curls were formed.

[0072] (4) Finger-friendly The finished hair strands were evaluated by touch for how easily they could be run through. 4 points: Very smooth to the touch. 3 points: Smooth to the touch. 2 points: Poor grip 1 point: Very poor grip.

[0073] (5) Gloss The shine of the finished hair strands was visually evaluated. 4 points: Very glossy 3 points: It is glossy. 2 points: It has almost no shine. 1 point: No shine at all

[0074] (6) Time reduction After performing the damage treatment and pretreatment described above, 20g of the first straightening agent (Qualine 100: manufactured by Arimino Co., Ltd.: 5% thioglycolic acid equivalent, pH 7.7) was applied to 10g of rinsed hair strands, left at 25°C for 10 minutes, then rinsed with water and dried with a hairdryer. Next, similar to the hair straightening treatment described above, a straight style was created using a hair iron. A 10g strand of hair that had been straightened was treated with 20g of the second straightening agent (Qualine OX 2nd agent: manufactured by Arimino Co., Ltd.), left at 25°C for 15 minutes, then rinsed with water and dried with a hairdryer. This strand of hair was designated as strand (i). The degree of curl straightening in hair bundle (i) was visually evaluated by comparing it with the following comparison hair bundle (ii). (Comparison hair bundle (ii): Prepared in the same manner as hair bundle (i), except that no pretreatment was performed, the first straightening agent was applied, and it was left at 25°C for 20 minutes.) 4 points: The curl is straightened more effectively than the comparison product. 3 points: The curl is straighter than the comparison target. Points 2: Compared to the comparison, the curl hasn't straightened out as much, and some wave remains. 1 point: The curl is not straightened at all compared to the comparison item.

[0075] (7) Odor during treatment The odor of the hair treatment agent was evaluated while applying it to the sample. 4 points: There is almost no odor during sample application. 3 points: Low odor during sample application. 2 points: There is a slight odor during sample application. 1 point: There is a considerable odor during sample application.

[0076] (8) Moist The texture of the finished hair strands was evaluated by touch. 4 points: Very moist 3 points: Moist. 2 points: It's dry. 1 point: It's very dry.

[0077] [Table 3]

[0078] [Table 4]

[0079] [Table 5]

[0080] [Table 6]

[0081] [Table 7]

[0082] [Table 8]

[0083] [Table 9]

[0084] [Table 10]

[0085] [Table 11]

[0086] [Table 12]

[0087] [Table 13]

[0088] [Table 14]

[0089] The hair treatment agents produced in Examples 1 to 48 yielded good results in evaluation items (1) to (8). Example 40 yielded particularly good results.

[0090] The present invention provides a hair treatment agent, a hair modification agent set, and a hair modification treatment method that can minimize damage to the hair while providing excellent hair-shaping capabilities such as straightening, curling, or permanent wave treatment, and can also result in hair with excellent manageability, shine, and a moist texture.

[0091] The hair treatment agent produced in Comparative Example 1 had poor curl-straightening and curl-forming capabilities because the thioglycolic acid equivalent value was less than the specified amount.

[0092] The hair treatment agent produced in Comparative Example 2 had a higher-than-specified amount of thioglycolic acid, resulting in hair damage and a poor finished texture.

[0093] The hair treatment agent produced in Comparative Example 3 had a lower thioglycolic acid equivalent value than specified, resulting in poor curl straightening and curl-forming capabilities. Furthermore, the finished texture was also poor.

[0094] The hair treatment agent produced in Comparative Example 4 had a higher-than-specified amount of thioglycolic acid, resulting in hair damage and a poor finished texture.

[0095] The hair treatment agent manufactured in Comparative Example 5 had a lower thioglycolic acid equivalent value than specified, resulting in poor curl straightening and curl-forming capabilities. Furthermore, the finished texture was poor, and there was a significant odor during the treatment.

[0096] The hair treatment agent produced in Comparative Example 6 had a higher-than-specified amount of thioglycolic acid, resulting in hair damage and a poor finished texture.

[0097] The hair treatment agent manufactured in Comparative Example 7 had a pH lower than the specified value, resulting in damage to the hair.

[0098] The hair treatment agent manufactured in Comparative Example 8 had a pH higher than the specified value, resulting in damage to the hair.

[0099] The hair treatment agent manufactured in Comparative Example 9 had a pH lower than the specified value, resulting in damage to the hair.

[0100] The hair treatment agent produced in Comparative Example 10 had a pH higher than the specified value, resulting in damage to the hair. The hair was rough to the touch, dry, and lacked shine.< / ph>

Claims

1. A hair treatment agent comprising at least one reducing agent (A) selected from ammonium thioglycolate, thioglycerin, and thiolactate, wherein the reducing agent (A) is in the range of 2.0 to 10.0% by mass in terms of thioglycolic acid, and the pH is 2 to 7. A hair modification agent set comprising a first hair modification agent containing a keratin fiber reducing substance in an amount of 2.0 to 11.0% by mass in terms of thioglycolic acid, and having a pH of 8 to 9.

5.

2. The hair treatment agent set according to Claim 1, wherein the hair treatment agent contains 0.2 to 1.0% by mass of diethylenetriaminepentaacetate (B).

3. The hair treatment agent set according to claim 1 or 2, wherein the hair treatment agent contains 0.2 to 2.0% by mass of steartrimonium chloride (C).

4. A step (I) of applying a hair treatment agent to hair, comprising at least one reducing agent (A) selected from ammonium thioglycolate, thioglycerin, and thiolactate, wherein the reducing agent (A) is in the range of 2.0 to 10.0% by mass in terms of thioglycolic acid, and the pH is 2 to 7. After step (I), step (II) is performed, in which a first hair modification agent is applied to the hair, which contains a keratin fiber reducing substance in an amount of 2.0 to 11.0% by mass in terms of thioglycolic acid and has a pH of 8 to 9.5, and A hair deformation treatment method comprising step (III) of applying a second hair deformation agent containing an oxidizing agent to the hair after step (II).

5. The hair deformation treatment method according to claim 4, wherein a step (I-a) of washing the hair is performed after step (I) and before step (II).

6. The hair deformation treatment method according to claim 4 or 5, wherein step (III) is performed on hair that has undergone step (II-a), in which step (II) is performed.

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