JP6663665B2 - Composition for protecting scalp - Google Patents

Description

  The present invention relates to a composition for protecting the scalp, and more particularly, to a scalp protection that reduces or prevents irritation to the scalp during hair treatment and favorably prevents discoloration or staining of the scalp due to hair treatment. To a composition for use.

  Conventionally, hair treatments such as a permanent treatment and a hair dyeing treatment are known. When the hair treatment agent used for such hair treatment adheres to the scalp, the scalp may be stimulated, causing pain and inflammation.

  Further, when a hair treatment agent having a dyeing or discoloring action adheres to the scalp, the scalp may be stained or discolored. Therefore, a scalp protection composition (protect oil) for protecting the scalp from a hair treatment agent by applying it to the scalp before hair treatment is known (for example, see Patent Documents 1 to 3).

JP-A-2004-99516 JP 2006-56848 A JP 2011-26258 A

  However, the conventional protect oils of Patent Literatures 1 to 3 may not be able to reduce or prevent irritation to the scalp of a hair treatment agent having a strong irritation to the scalp such as a perm agent or a bleaching agent. . Therefore, there is room for improvement regarding the effect of reducing or preventing irritation to a hair treatment agent with strong irritation.

  For this reason, the scalp during hair treatment is better alleviated or prevented from irritation from the hair dye treatment agent, and the scalp is more preferably dyed or discolored by the hair treatment agent having a dyeing or discoloring action. It has been desired to develop a composition for protecting the scalp that can prevent the scalp.

  The present invention has been made in view of such problems of the related art, and its object is to alleviate or prevent irritation to the scalp during hair treatment, and to discolor or dye the scalp by hair treatment. It is an object of the present invention to provide a scalp protecting composition that favorably prevents the scalp from being damaged.

  According to the present invention, the following scalp protecting composition is provided.

[1] A scalp protecting composition for forming a protective film on the scalp to protect the scalp by being applied to the scalp before treating the hair, wherein the composition has a total mass of 38 to 99.99. % Hydrocarbons and 0.01 to 21% by weight of the total mass of hydrophobic silica particles , wherein the hydrocarbons comprise petrolatum, liquid isoparaffin, heavy liquid isoparaffin and light liquid isoparaffin. A scalp protecting composition which is at least one selected from the group .

[2] The composition for protecting a scalp according to the above [1], which has a viscosity at 24 ° C of 50 to 10,000 mPas.

[3] The composition for protecting a scalp according to the above [1] or [2], comprising the two or more hydrocarbons.

[4] The hydrocarbon is
With Vaseline,
At least one selected from the group consisting of liquid isoparaffin, heavy liquid isoparaffin and light liquid isoparaffin ;
The scalp protecting composition according to any one of [1] to [3], comprising:

[ 5 ] The composition for protecting a scalp according to any one of [1] to [ 4 ], further comprising a surfactant.

[ 6 ] The above-mentioned [ 5 ], wherein the surfactant is at least one of an anionic surfactant, a cationic surfactant, an amphoteric surfactant, and a nonionic surfactant having an HLB value of 10 or less. 4. The composition for protecting a scalp according to item 1.

  The scalp protecting composition of the present invention can prevent the hair treatment agent from coming into contact with the scalp during hair treatment, and can alleviate or prevent the scalp from receiving the hair treatment agent. In addition, it is possible to prevent the scalp from being stained or discolored by the hair treatment agent.

1 is a photograph showing a scalp protecting effect when a scalp protecting composition of the present invention is used. 9 is a photograph showing a scalp protecting effect when the scalp protecting composition of Comparative Example 6 was used. It is a photograph which shows the hair after applying the composition for scalp protection of this invention to hair and performing a hair dyeing process. It is explanatory drawing which illustrates typically the state which exhibits the protective effect when the composition for scalp protection of this invention is apply | coated to a scalp. It is a figure which shows typically the three-dimensional network structure formed of the hydrophobic silica particle and the hydrocarbon in the composition for scalp protection of this invention.

  Hereinafter, embodiments of the present invention will be described, but the present invention is not limited to the following embodiments, and based on ordinary knowledge of those skilled in the art, without departing from the spirit of the present invention. It is to be understood that modifications, improvements, etc., of the embodiments described above are also included in the scope of the present invention.

[1] Composition for protecting scalp:
The composition for protecting the scalp of the present invention is used for the scalp before hair treatment, and is a hydrocarbon which is 38 to 99.99% by mass of the total mass and 0.01 to 21% by mass of the total mass. And certain hydrophobic silica particles.

  Such a composition for protecting the scalp forms a protective film on the scalp by being applied to the scalp before the hair treatment, and alleviates the irritation to the scalp in the hair treatment performed after the formation of the protective film. In addition to preventing or preventing the scalp from staining or discoloring.

  Here, the scalp protecting composition (protect oil) is an oil applied to the scalp. For example, it is difficult to apply it to the scalp if it has a high viscosity (small fluidity) such as a protect cream that protects the skin by applying it on the forehead and hairline. Here, when a liquid oil is used as the oil (oil component) used for the protect oil, it can be easily applied to the scalp. For this reason, the protect oil generally contains a large amount of liquid oil, and is selected to have a liquid state. However, liquid oil easily penetrates the scalp, and the effect of forming a protective film on the scalp is small. Therefore, it is difficult to obtain a sufficient protective effect on the scalp with the liquid protect oil. That is, dyeing of the hair treatment agent becomes easy, and irritation by the hair treatment agent or the like during hair treatment becomes easy to feel.

  Thus, the present inventors have made intensive studies and found that the scalp protecting effect of the scalp protecting composition is enhanced by using a predetermined ratio of hydrophobic silica particles. It is considered that the hydrophobic silica particles are satisfactorily dispersed in the oil base and form a net structure (three-dimensional network structure), thereby enhancing the protective power of the protect oil. That is, when a predetermined amount of the hydrophobic silica particles is added to the oil, it is considered that the net structure is formed in a state where the hydrophobic silica particles surround and hold the oil particles (FIG. 5). Therefore, even if oil having high fluidity is used, a strong protective film can be formed, and the scalp can be protected from dyeing and irritation by the hair treatment agent. The net structure is easily deformed when a force is applied. Therefore, the composition for protecting the scalp of the present invention can be spread over the entire scalp even when applied on the scalp where hair is densely grown. In addition, such a function originates in the property (thixotropic property) that a viscosity becomes low when it receives a shear stress. In addition, due to this property, the composition for protecting the scalp of the present invention can be easily applied on the scalp where hair has grown densely, while the protective film formed on the scalp under no stress is applied. Since the viscosity for maintaining the scalp is maintained, the composition for protecting the scalp does not drip on the face.

  FIG. 4 is an explanatory view schematically illustrating a state in which a protective effect is exhibited when the scalp protecting composition of the present invention is applied to the scalp. Even when the hair treatment agent 11 adheres to the scalp 30, the protective layer 21 formed by a part of the liquid (highly fluid) oil penetrating into the scalp (stratum corneum) does not penetrate the scalp. A protective effect (protective effect) is exerted by the protective film 22 composed of the oil 22a and the hydrophobic silica particles 22b left on the scalp. The composition for protecting the scalp of the present invention has a high fluidity (low viscosity) that can be easily spread on the scalp, but the scalp is firmly protected by a protective film obtained by blending oil and hydrophobic silica particles. To protect. In this respect, it is different from a protect cream (skin protection composition) which is applied on the forehead and hairline and forms a thick protective film with low fluidity to protect the skin.

  The composition for protecting a scalp of the present invention can be used as a protective agent for a hair treatment agent usually used in hair treatment. Here, examples of the hair treatment agent include a perm agent, a hair dye, a bleach, and the like.

  Examples of the perm agent include a thio-based heated two-bath perm, a cis-based heated two-bath perm, a thio-based cold two-bath perm, a cis-based cold two-bath perm, and a thio-based cold one-bath perm. Preparation, thio-based first-agent preparation, exothermic two-bath perm agent, thio-based cold two-bath hair straightener, thio-based heated two-bath hair straightener, thio-based high-temperature hairdressing iron Two-bath hair straightener, sulfite-based perm, cysteamine-based perm, butyrolactone thiol-based perm, thioglycerin-based perm, and the like.

  Examples of hair dyes include alkaline oxidative hair dyes, acidic oxidative hair dyes, acidic hair dyes (hair manicure), HC hair dyes, basic hair dyes, so-called henna, legal dyes (eg, Black 401), Silver salts, pigments and the like.

  Conventionally, the existing protective agent may not be able to sufficiently prevent irritation to the scalp and staining of the scalp. However, according to the composition for protecting the scalp of the present invention, irritation to the scalp by the hair treatment agent. And the scalp can be satisfactorily prevented from being dyed. That is, the scalp protecting composition of the present invention exerts a higher scalp protecting effect (irritation preventing effect and dyeing preventing effect) than the conventional protective agent.

  The composition for protecting the scalp of the present invention exhibits a high protective effect (irritative effect and anti-dyeing effect) as described above. Does not inhibit hair dyeing (see FIG. 3). This is presumably because the scalp protecting composition has different permeability to the scalp and hair. In other words, the composition for protecting the scalp has low permeability to the hair, and only a thin film (protective film) of the composition for protecting the scalp is formed on the cuticle constituting the hair. Is small. On the other hand, the composition for protecting the scalp has high permeability to the scalp, and a thick film (protective film) of the composition for protecting the scalp is formed on the surface layer (stratum corneum) of the scalp. Therefore, the protective effect against the hair dye is large. FIG. 3 is a photograph showing the hair after the composition for protecting the scalp of the present invention is applied to the hair and subjected to a hair dyeing treatment.

  In addition, when the scalp protecting composition of the present invention is used, the hair treatment agent attached to the scalp can be easily washed away with water. Further, the hair treatment agent attached to the hair is easily washed away with water. The temperature of the water to be used can be specifically 37 ° C. or lower. Therefore, even if it is necessary to use relatively low-temperature water (specifically, 37 ° C. or lower) depending on the season, facility conditions, user's desires, etc., the scalp protecting composition of the present invention can be used. , Scalp and / or hair can be easily washed away from the treatment.

  Furthermore, when the composition for protecting a scalp of the present invention is used, the scalp after washing with water is hardly sticky. That is, the protective film formed by the composition for protecting the scalp of the present invention can be easily washed away with water. It is considered that this is because the hydrophobic silica particles in the scalp protecting composition are partially gelled by contact with a large amount of water and easily peel off from the scalp.

  Here, in the scalp protection composition of the present invention, the hydrophobic silica particles are well dispersed in the hydrocarbon base. Further, it is considered that the hydrophobic silica particles are linked to each other to form a three-dimensional network structure. Then, it is considered that the three-dimensional network structure prevents the stimulus component in the hair treatment agent from reaching the scalp, thereby preventing scalp irritation. It is also considered that the dyeing components in the hair treatment agent are prevented from entering the scalp, thereby preventing the scalp from being dyed.

[1-1] Hydrophobic silica particles:
The hydrophobic silica particles preferably have an average primary particle diameter of 1 nm to 15 μm, more preferably 5 nm to 1 μm. By using the hydrophobic silica particles whose primary particles have an average particle diameter of 1 nm to 15 μm, the hydrophobic silica particles in the hydrocarbon component are more uniformly dispersed. Therefore, an even higher irritation prevention effect and dyeing prevention effect can be obtained. Also, it has good spreadability. That is, the composition for protecting the scalp of the present invention can be favorably applied on the scalp.

  Here, the average particle diameter of the primary particles referred to in the present specification means that when the average particle diameter of the primary particles is 1 μm or less, the average particle diameter is measured by a dynamic scattering method (photon correlation method), and the particle diameter analysis method “CONTIN” is used. Is a measured value (mode diameter) derived from the number distribution using the "method". When the average particle diameter of the primary particles is more than 1 μm, it is a value (median diameter) measured by a laser diffraction method.

  In the present invention, a higher scalp protection effect can be obtained by using hydrophobic silica particles. In addition, the hair treatment agent can be easily washed away with water. Furthermore, because of its higher affinity for oily components and better mixing with hydrocarbons, application onto the scalp (including spreading and spraying) is easy.

  Commercially available hydrophobic silica particles include, for example, AEROSIL R972, AEROSIL R974, AEROSIL R104, AEROSIL R106, AEROSIL R202, AEROSIL R805, AEROSIL R812, AEROSIL R812S, AEROSIL R816, AEROSIL R7200, AEROSILOR8, AEROSILR8 AEROSIL R972 Pharma (manufactured by Evonik), VM-2270 Aerofine Fine Particles (manufactured by Dow Corning), HDK H15, HDK H15P, HDK H20, HDK H30, HDK H18, HDK H2000, HDK H1018, HDK H2050, HD 004 (manufactured by Asahi Kasei Wacker Silicone Co., Ltd.), and the like.

  Here, the hydrophobic silica particles are silica particles whose surfaces have been subjected to a hydrophobic treatment. The hydrophobization treatment is, for example, a treatment for introducing a hydrophobic group into the surface of the silica particle by dimethylsilylation or trimethylsilylation of a hydrophilic group (for example, hydroxyl group (-OH)) present on the surface of the silica particle. .

  The content ratio of the hydrophobic silica particles is from 0.01 to 21% by mass, preferably from 0.25 to 15% by mass, and more preferably from 1.0 to 9.0% by mass based on the total mass of the composition for protecting the scalp. Is more preferably 3.0 to 9.0% by mass. When the content is in the above range, the scalp can be alleviated or prevented from being stimulated by the hair treatment agent, and the scalp can be prevented from being stained or discolored by the hair treatment agent. Further, by setting the content ratio of the hydrophobic silica particles to 0.01% by mass or more of the total mass of the composition for protecting the scalp, it is easily removed from the scalp only by washing with water after the hair treatment. If the content of the hydrophobic silica particles is more than 21% by mass of the total mass of the composition for protecting the scalp, it becomes difficult to secure fluidity and operability that can be spread on the scalp.

[1-2] Hydrocarbon:
The scalp protecting composition of the present invention contains a hydrocarbon as a base. Since hydrocarbons have high hydrophobicity (lipophilicity), hydrophobic silica particles can be more stably dispersed. Further, since a water-based hair treatment agent hardly penetrates into the protective film containing hydrocarbons, a high protective effect can be obtained by using hydrocarbons as a base. It is further believed that the three-dimensional network formed by the hydrophobic silica particles can be strengthened.

  The content ratio of the hydrocarbon is preferably 38 to 99.99% by mass, more preferably 47 to 99.99% by mass, and particularly preferably 79 to 99% by mass. When the content is in the above range, a high protective effect can be obtained.

  Examples of the hydrocarbon include a saturated or unsaturated hydrocarbon that can be used as a base for the composition for protecting the scalp, and among them, a paraffinic hydrocarbon having 15 or more carbon atoms is preferable. Specifically, petrolatum, ceresin, squalane, squalene, α-olefin oligomer, hydrogenated polydecene, polydecene, dodecane, solid paraffin (paraffin wax), mineral oil (liquid paraffin), hydrogenated polyisobutene (liquid isoparaffin, heavy fluid Isoparaffin, light liquid isoparaffin), isododecane, pristane, polyethylene wax, microcrystalline wax and the like. Above all, at least one selected from petrolatum, liquid isoparaffin, heavy liquid isoparaffin and light liquid isoparaffin can be used.

  It is preferable to use two or more hydrocarbons in combination. By combining two or more hydrocarbons, operability (fluidity) that can be spread well on the scalp can be secured.

  The combination of two or more hydrocarbons can be at least two selected from petrolatum, liquid isoparaffin, heavy liquid isoparaffin, and light liquid isoparaffin. Combinations of two or more hydrocarbons include, for example, a combination of petrolatum and liquid isoparaffin, a combination of heavy liquid isoparaffin and liquid isoparaffin, a combination of petrolatum and light liquid isoparaffin, and a combination of heavy liquid isoparaffin and light liquid isoparaffin. Combinations can be liquid isoparaffin and light liquid isoparaffin. Among them, a combination of petrolatum and liquid isoparaffin or a combination of heavy liquid isoparaffin and liquid isoparaffin is particularly preferable since an excellent scalp protecting effect can be obtained. Further, the hydrocarbon essentially contains petrolatum and preferably further contains at least one selected from the group consisting of liquid isoparaffin, heavy liquid isoparaffin and light liquid isoparaffin. This can both reduce or prevent irritation to the scalp during hair treatment and achieve both discoloration or staining of the scalp by hair treatment.

  The combination of two or more hydrocarbons is selected from the group consisting of petrolatum, ceresin, hydrogenated polydecene, polydecene, solid paraffin, polyethylene wax and microcrystalline wax, and squalane, squalene, α A combination with one hydrocarbon selected from the group consisting of olefin oligomers, hydrogenated polydecene, polydecene, dodecane, mineral oil, liquid isoparaffin, light liquid isoparaffin, heavy liquid isoparaffin, isododecane and pristane. That is, at least one type of hydrocarbon that is solid at room temperature and at least one type of hydrocarbon that is liquid at room temperature can be combined.

  The value of the mass ratio between the hydrocarbon and the hydrophobic silica particles (mass% of hydrocarbon / mass% of hydrophobic silica particles) is preferably 1.8 to 10,000, and is 3.1 to 100. More preferably, it is particularly preferably from 11.0 to 26.3. If the value of the mass ratio is less than 1.8, a dosage form suitable for use may not be maintained. If the value of the mass ratio is more than 10,000, the composition for protecting the scalp may not be able to sufficiently exert the protective effect.

  When combining a hydrocarbon that is solid at room temperature and a hydrocarbon that is liquid at room temperature, the value of the mass ratio between the hydrocarbon that is solid at room temperature and the hydrocarbon that is liquid at room temperature is 0.1 to 13; To 12.8, more preferably 0.85 to 4.1. When the value of the mass ratio is less than 0.1, the viscosity becomes excessively small, so that during the hair treatment, the scalp protection composition may run down from the scalp to the face together with the hair treatment agent. is there. On the other hand, if the value of the mass ratio is more than 13, sufficient fluidity for applying the scalp protecting composition to the scalp may not be obtained, and the composition may be hindered by the hair and difficult to apply to the scalp. .

  Further, the content ratio of the hydrocarbon which is solid at ordinary temperature can be 70% by mass or less based on the total mass of the scalp protection composition, and can be 60% by mass or less based on the total mass. It can be 50% by mass or less based on the mass. When the content is in the above range, sufficient fluidity for applying the composition for protecting the scalp to the scalp can be obtained, and washing off from the scalp or hair becomes easy.

[1-3] Viscosity of composition for protecting scalp:
The viscosity of the composition for protecting a scalp of the present invention is 50 to 10,000 mPas (cP) at room temperature (24 ° C.), preferably 100 to 8,000 mPas, and 1,000 to 5,000 mPas. Is more preferred. When the viscosity is less than 50 mPas, the composition for protecting the scalp may run down from the scalp to the face together with the hair treatment agent during hair treatment. At that time, if the hair treatment agent contains a particularly irritating component, the component may enter the eyes, which is dangerous. On the other hand, when the viscosity is more than 10.000 mPas, sufficient fluidity for applying the scalp protecting composition to the scalp may not be obtained, and the composition may be hindered by the hair and difficult to apply to the scalp.

[1-4] Other components:
The scalp protection composition of the present invention may further contain other components other than the above components, if necessary.

[1-4-1] Other components:
The scalp protection composition of the present invention may further contain an oily component other than hydrocarbons, if necessary. Oil components other than hydrocarbons include waxes, higher alcohols, higher fatty acids, vegetable oils and fats, animal oils and fats, esters, silicones and the like.

  Examples of the silicone contained in the scalp protecting composition of the present invention include linear or cyclic silicones such as dimethicone and cyclomethicone, and particularly include dimethicone. The amount of silicone contained in the scalp protection composition of the present invention is preferably less than 60% by mass, and more preferably 10.0% by mass or less. If the amount of the silicone exceeds 60% by mass or more, the hair treatment agent easily penetrates into the protective film formed by the composition for protecting the scalp of the present invention, and thus it is considered that a sufficient protective effect cannot be obtained.

  In addition, the composition for protecting the scalp of the present invention, if necessary, for example, water, polyhydric alcohol, lower fatty acid, lower alcohol, antioxidant, storage stabilizer, fragrance, moisturizer, anti-inflammatory agent, thickening Agents, UV absorbers, pH adjusters, plant extracts, animal extracts, preservatives, antibacterial agents and the like.

[1-4-2] Surfactant:
The scalp protecting composition of the present invention may contain a surfactant. As the surfactant, conventionally known surfactants can be used. Specific examples of the surfactant include an anionic (anionic) surfactant, a cationic (cationic) surfactant, a nonionic (nonionic) surfactant, and an amphoteric surfactant. . Among these, at least one of an anionic surfactant, a cationic surfactant, an amphoteric surfactant, and a nonionic surfactant having an HLB value of 10 or less is preferable. When these are used, the scalp protecting effect is further improved, so that the stimulation of the hair treatment agent to the scalp and the staining of the scalp can be more favorably prevented.

  Examples of the anionic surfactant include alkyl ether sulfate, alkyl sulfate, alkenyl ether sulfate, alkenyl sulfate, olefin sulfonate, alkane sulfonate, alkyl or alkenyl ether carboxylate, α-sulfone Fatty acid salts, N-acyl amino acid surfactants, mono- or diester phosphate surfactants, and sulfosuccinates are exemplified. Examples of the counter ion of the anionic group of these surfactants include a sodium ion, a potassium ion, and triethanolamine. Examples of the alkyl ether sulfate include sodium laureth sulfate and sodium lauryl sulfate. Examples of the N-acylamino acid type surfactant include N-lauroyl, sodium L-glutamate and the like. Among these, sodium lauryl sulfate is preferred.

  Examples of the cationic surfactant include an alkyltrimethylammonium salt, an alkenyltrimethylammonium salt, a dialkyldimethylammonium salt, a dialkenyldimethylammonium salt and an alkylloamidopropyldimethylamine. Examples of the alkyltrimethylammonium salt include stearyltrimethylammonium chloride. Specific examples of the dialkyldimethylammonium salt include distearyldimethylammonium chloride (distearyldimonium chloride). Examples of the counter ion of the cationic group of these surfactants include chloride ion, bromide ion, iodide ion, alkyl sulfate ion, and saccharin. Among these, distearyl dimethyl ammonium chloride (distearyl dimonium chloride) is preferred.

  Examples of the amphoteric surfactant include an amino acid type, a betaine type, and a natural product. Specific examples thereof include sodium alkylamino fatty acid, alkyl betaine, alkylamine oxide, alkyldimethylamine oxide, alkylcarboxybetaine, alkylamine oxide, and lauryl. Betaine, stearyl betaine, 2-alkyl-N-carboxymethyl-N-hydroxyethyl isodazolinium betaine, lauryl dimethylamine oxide, lauryl dimethylamino acetate betaine, stearyl dimethylamino acetate betaine, dodecylaminomethyldimethylsulfopropyl betaine, octadecylamino Methyl dimethyl sulfopropyl betaine, cocamidopropyl betaine, cocamidopropyl hydroxysultaine, cocamido MEA, 2-alkyl N-carboxymethyl-N-hydroxyethylimidazolinium betaine, sodium lauroylglutamate, potassium lauroylglutamate, lauroylmethyl-β-alanine, lauryldimethylamine N-oxide, oleyldimethylamine N-oxide, lecithin, etc. . Among these, betaine-type amphoteric surfactants are preferred, and lauryl betaine is particularly preferred.

  As nonionic surfactants, for example, polyoxyalkylene alkyl ether, polyoxyalkylene alkenyl ether, polyoxyethylene sorbitan fatty acid ester, sucrose fatty acid ester, sorbitan fatty acid ester, alkyl saccharide surfactant, glycerin fatty acid ester, poly Oxyethylene hydrogenated castor oil, fatty acid alkanolamide, coconut oil fatty acid ethanolamide, alkylamine oxide and the like can be mentioned. Examples of the polyoxyalkylene alkyl ether include polyoxyethylene lanolin alcohol (Runes), polyoxyethylene cetyl ether (Ceteth), polyoxyethylene stearyl ether (Steares), polyoxyethylene oleyl ether (Ores), Palace and the like. Can be Among them, polyoxyethylene lanolin alcohol (Runes), particularly Runes-5, polyoxyethylene alkylamine, sorbitan trioleate, and polyoxyethylene lauryl ether are preferable.

  When a nonionic surfactant is used, its HLB is preferably 10 or less, more preferably 1.8 to 9.6, and particularly preferably 1.8 to 5.1. By setting the content in such a range, the degree of lipophilicity of the composition for protecting the scalp is increased, and it is difficult to form an emulsion. Therefore, even when the hair is treated, the hair treatment agents such as the perm agent and the color agent are protected. Difficult to penetrate the membrane.

  One surfactant may be used alone, or two or more surfactants may be used in combination.

  The content of the surfactant is preferably 2 to 30.0% by mass, and more preferably 5.0 to 15.0% by mass based on the total mass of the composition for protecting the scalp. When the content of the surfactant is within the above range, the scalp protecting composition can be more easily washed off from the scalp and hair in the washing step, and the dispersion state of the hydrophobic silica particles can be stabilized. So better protection of the scalp is possible.

[2] Use:
The composition for protecting the scalp of the present invention is used for protecting the scalp from a hair treatment agent. That is, it prevents or alleviates the irritation of the hair treatment agent to the scalp, and also favorably prevents the hair treatment agent from staining the scalp. That is, specifically, the composition for scalp protection is formed by applying a composition for scalp protection on the scalp to form a protective film on the scalp, and performing hair treatment after the formation of the protective film. It is possible to prevent the scalp from receiving irritation and prevent the scalp from being stained in the applied portion.

  Here, "application" is a concept that includes spraying the composition for protecting the scalp directly on the scalp and also on the head. When the composition for protecting the scalp is applied to the scalp, a protective film is formed on the scalp, and even when the composition for protecting the scalp adheres to the hair, the composition for protecting the scalp does not inhibit the dyeing of the hair (FIG. 3).

  The composition for protecting the scalp of the present invention can be in a liquid state, a semi-solid state, or a gel state at normal temperature.

  The scalp protecting composition of the present invention is used by applying it on the scalp before hair treatment. If necessary, in addition to the scalp, the composition may be applied to a portion to which the hair treatment agent may adhere (for example, a border between a forehead, a temple, an ear, and the like). Examples of the method of application include a method using a finger, a palm, a brush, a comb, a brush, a roller, a container with a nozzle, a spray, and the like.

  After forming a protective film with the composition for protecting the scalp of the present invention, the hair is treated by a conventionally known method using a hair treating agent. In the step of washing the hair treatment agent with water after the hair treatment (washing step), the scalp protection composition of the present invention starts flowing off the scalp as soon as it is exposed to water and is easily removed by rubbing with a weak force. . Also, the scalp does not stick after washing.

  In the washing step, water of 37 to 40 ° C. is usually used. However, depending on the season, facility conditions, user's request, and the like, washing may be performed with water at a temperature of, for example, 35 ° C. or less. When the temperature of the water is low as described above, the hair treatment agent generally tends to be hard to fall off the scalp. However, when the composition for protecting the scalp of the present invention is used, even if the temperature of the water is 37 ° C. or less, it is extremely low. The hair treatment agent can be easily and well washed off.

  Hereinafter, the present invention will be specifically described based on examples, but the present invention is not limited to these examples.

[Preparation of composition for protecting scalp]
(Example 1)
After weighing 48.5 g (97.0% by mass) of petrolatum (trade name: Special White Petrolatum, manufactured by Sanwa Yushi Kogyo Co., Ltd.) and placing it in a beaker, placing the beaker in a water bath at 80 ° C. to remove petrolatum Heated to melt. After the vaseline is melted, 1.5 g (3.0% by mass) of hydrophobic silica particles (trade name: AEROSIL R812, manufactured by Evonik, average particle size: 7 nm) is added, and the mixture is mixed with a small stirrer until a uniform composition is obtained. After stirring, 50.0 g of the composition for protecting the scalp was obtained.

(Example 2)
A composition for protecting the scalp was obtained in the same manner as in Example 1 except that the preparation was performed using the compounding amounts described in Table 1.

(Example 3)
Vaseline (trade name: Special White Petrolatum, manufactured by Sanwa Yushi Kogyo Co., Ltd.) 30.0 g (60.0% by mass) and liquid isoparaffin (trade name: Pearl Dream, manufactured by NOF CORPORATION) 18.5 g (37. 0% by mass) in a beaker and mixed to obtain a mixture. Thereafter, the beaker was placed in a water bath at 80 ° C., and the mixture was heated and melted. After the mixture was melted, 1.5 g (3.0% by mass) of hydrophobic silica particles (trade name: AEROSIL R812, manufactured by Evonik, average particle size: 7 nm) was added, and the mixture was stirred with a small stirrer until a uniform composition was obtained. After stirring, a composition for protecting the scalp was obtained.

(Examples 4 to 45, Comparative Examples 1 to 4)
A scalp protecting composition was obtained in the same manner as in Example 3 except that hydrocarbons were prepared in the types and amounts shown in Tables 1 and 2. As hydrocarbons, in addition to Vaseline and liquid isoparaffin, heavy liquid isoparaffin (trade name: Pearl Ream 18, manufactured by NOF CORPORATION) and light liquid isoparaffin (trade name: Pearl REAM 4, manufactured by NOF CORPORATION) Using.

(Examples 46 to 55, Comparative Examples 5 and 6)
A composition for protecting a scalp was obtained in the same manner as in Example 3, except that the preparation was performed using hydrocarbons and silicone oils of the types and blending amounts shown in Table 3. As the silicone oil, methyl polysiloxane (dimethicone) (trade name: SH200 FRUID, manufactured by Dow Corning) and cyclopentasiloxane (cyclomethicone) (trade name: SH245 FRUID, manufactured by Dow Corning) were used.

(Examples 56 to 83)
A composition for protecting the scalp was obtained in the same manner as in Example 3, except that the preparation was performed by blending the types and amounts of hydrocarbons and surfactants described in Tables 4 to 6.

  Various evaluations were performed using the scalp protecting composition obtained above.

  2 g of each of the compositions for protecting the scalp was taken and applied to half of the surface of the pig skin to form a protective film. Next, 5 g of a hair dye (trade name: Wella Coleton Perfect 1 Tone Black, manufactured by Procter & Gamble Japan) and a hair dye oxidizer (trade name: Welloxone Perfect, Procter & Gamble Japan) 5 g (produced by Sharp Corporation) (hereinafter referred to as “hair dye mixture”), scooped with a comb brush, and applied to the entire surface of the pig skin on which the protective film was formed. After standing for 15 minutes, the hair dye mixture was washed off with water (washing step). After wiping off the moisture, each evaluation of "scalp protection effect", "scalp wash-off", "hair dye", and "hair wash-off" was performed by the following methods.

[Scalp protection effect]
Further, the protective effects of all the scalp protecting compositions of Examples 1 to 83 and Comparative Examples 1 to 6 were visually evaluated. The evaluation criteria were “excellent” when the pig skin was not stained or discolored, “good” when the pig skin was not stained or discolored, and “good” when the pig skin was slightly stained or discolored. "Possible" and those in which the pig skin was clearly discolored or discolored were "impossible".

[Rinse off the scalp]
When the hair dye mixture was washed away with water together with the composition for protecting the scalp (washing step), the ease of washing off the pig skin was evaluated. Those with very good washing were rated "Excellent", those with good washing were rated "Good", those with slightly good washing were "OK", and those with poor washing were "impossible".

[Dyeing of hair]
A hair bundle of gray human hair is prepared, and the scalp protecting compositions of Examples 1 to 83 and Comparative Examples 1 to 6 are imprinted on the lower half of the hair bundle (see “application portion” in FIG. 3). Applied. Next, 5 g of a hair dye (trade name: Wella Coleton Perfect 1 Tone Black, manufactured by Procter & Gamble Japan) and a hair dye oxidizer (trade name: Welloxon Perfect, Procter & Gamble Japan) 5 g) (hair dye mixture) was scooped with a comb brush and applied to the entire hair bundle. After standing for 15 minutes, the hair dye mixture was washed off with water (washing step). The water was wiped off with a paper towel, and the hair bundle was visually observed. Those with very good dyeing were rated "excellent", those with good dyeing as "good", those with slightly good dyeing as "OK", and those with poor dyeing as "impossible".

  FIG. 3 shows a photograph of a hair bundle that was evaluated for “hair dyeing” in Example 19 and evaluated as “excellent”. As can be seen from FIG. 3, it was confirmed that the entire dyed hair bundle was dyed with the same lightness. That is, it can be seen that the hair of the portion to which the composition for protecting the scalp of the present invention is applied and the hair of the portion to which the composition for protecting the scalp is not applied are similarly dyed. Thus, it can be seen that the composition for protecting the scalp of the present invention does not inhibit the dyeing of hair in the hair dyeing treatment.

[Rinse hair]
In the step of washing the hair dye mixture with water together with the composition for protecting the scalp (washing step), the ease of washing away from the hair was evaluated. Those with very good washing were rated "Excellent", those with good washing were rated "Good", those with slightly good washing were "OK", and those with poor washing were "impossible".

  From the above results, the composition for protecting the scalp containing a predetermined amount of the hydrophilic silica, while reducing or preventing the irritation to the scalp during the hair treatment, and favorably discoloring or dyeing the scalp by the hair treatment. It can be seen that it can be prevented. Specifically, it was found that a scalp protecting composition containing hydrophobic silica particles in an amount of 0.01% by mass or more of the total mass of the scalp protecting composition has a scalp protecting effect (Examples 1 to 45). And Comparative Example 3). Further, those containing hydrophobic silica particles at a ratio of 1.0 to 9.0% by mass of the total mass (especially 3.0 to 9.0% by mass of the total mass) have a high protective effect. Was.

  In addition, it was found that the composition for protecting the scalp containing two or more kinds of hydrocarbons not only has a protective effect on the scalp, but also has a good evaluation with respect to hair dyeing, scalp washing, and hair washing (for example, Examples 1, 2 and Example 3). In particular, it was found that when a combination of petrolatum and liquid isoparaffin or a combination of heavy liquid isoparaffin and liquid isoparaffin was used, an excellent scalp protecting effect was obtained (Examples 3, 14).

  From the results in Table 3, it was found that a scalp protecting effect was obtained when a scalp protecting composition containing a hydrocarbon exceeding 38% by mass of the total mass was used (Example 55, Comparative Example 5).

  According to the results of Tables 4 to 6, a high scalp protection effect is obtained when an anionic surfactant, an amphoteric surfactant, a cationic surfactant, or a nonionic surfactant having an HLB value of 10 or less is blended. It turned out to be obtained. It was found that a particularly high scalp protection effect was obtained when a nonionic surfactant having an HLB value of 5.1 or less was used.

  In addition, according to the results of Tables 4 to 6, when the composition for protecting the scalp containing the surfactant was used, both the “washing out of the scalp” and the “washing out of the hair” were evaluated as “excellent”. Has been obtained. In other words, it is understood that the scalp protecting composition containing the surfactant can be very easily washed off from both the scalp and the hair in the washing step. In the examples of the present invention, among the other compositions not containing a surfactant, there is a composition that has been evaluated as “excellent”, but the scalp protection composition containing a surfactant The evaluation of “excellent” is even higher than the evaluation of “excellent” of the composition for protecting the scalp containing no surfactant.

[viscosity]
For Examples 1, 2, 52, 32, 22, and 65, the viscosity was measured. The viscosity was measured at room temperature (24 ° C.) using a TVC-7 type viscometer (manufactured by Toki Sangyo Co., Ltd., rotation speed: 20 rpm). The results are shown in Tables 7 and 8.

  Regarding the scalp protecting compositions of Examples 52, 32, 22, and 65 having a viscosity in the range of 50 to 10,000 mPas, the “scalp protecting effect”, “rinse out scalp”, “dying hair”, “rinse out hair” It can be seen that good evaluations can be obtained for all the items of "."

  The scalp protecting composition of the present invention can be suitably used as a protective agent for preventing irritation to the scalp or staining of the scalp during hair treatment.

11: hair treatment agent, 21: protective layer, 22: protective film, 22a: oil, 22b: hydrophobic silica particles, 30: scalp.

Claims (6)

A scalp protection composition for forming a protective film on the scalp to protect the scalp by being applied to the scalp before treating hair,
38 to 99.99% by mass of the total mass of hydrocarbons and 0.01 to 21% by mass of the total mass of hydrophobic silica particles,
A scalp protecting composition wherein the hydrocarbon is at least one selected from the group consisting of petrolatum, liquid isoparaffin, heavy liquid isoparaffin, and light liquid isoparaffin.   The composition for protecting a scalp according to claim 1, having a viscosity at 24C of 50 to 10,000 mPas.   The scalp protecting composition according to claim 1 or 2, comprising two or more of the hydrocarbons. The hydrocarbon is
With Vaseline,
At least one selected from the group consisting of liquid isoparaffin, heavy liquid isoparaffin and light liquid isoparaffin ;
The composition for protecting a scalp according to any one of claims 1 to 3, comprising:   The scalp protecting composition according to any one of claims 1 to 4, further comprising a surfactant.   The scalp according to claim 5, wherein the surfactant is at least one of an anionic surfactant, a cationic surfactant, an amphoteric surfactant, and a nonionic surfactant having an HLB value of 10 or less. Protective composition.