JP2001316422A - Copolymer and cosmetic containing it - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a water-soluble copolymer and/or a salt thereof capable of forming a hydrophobic coating film when used, and cosmetics containing it and useful for hair dressing and the like. SOLUTION: The copolymer is made from constituent monomers comprising derivatives of acrylic acid and methacylic acid, has a hydrophilic group and a hydrophobic group in the same molecule, and has a cloud point at 30 to 70 deg.C. The cosmetics contain the copolymer and/or its salt.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

TECHNICAL FIELD The present invention relates to a copolymer having a cloud point at 30 to 70 ° C. and a cosmetic containing the same.

[0002]

2. Description of the Related Art In the field of external preparations for skin such as cosmetics, polymers such as homopolymers or copolymers are used as film-forming agents for the purpose of preventing water from dispersing in the skin or for the purpose of shaping and maintaining the shape of hair. Widely used. In the former, those which exhibit a transparent and uniform solution together with an aqueous carrier are used, and in the latter, those which are insoluble in water but soluble in alcohols are mainly used. The reason why such a solution is used in the latter is that the hair which is easily mixed with the aqueous carrier as in the former may lose its hair styling ability due to sweat or rain. This is because if the form is not easily mixed with water as in the latter case, the hair styling properties are hardly impaired by such sweat or rain. However, in such a polymer, it is essential to use a lower alcohol such as ethanol or a liquefied gas such as natural gas or Freon. For this reason, it is presently difficult to use such preparations from environmental considerations. In addition, when hair and the like are treated with such a preparation, the stain cannot be easily removed only with water, and there is a problem such as deterioration of the frame of the glasses due to ethanol used as a solvent. It was desired to solve such problems.

On the other hand, copolymers and / or salts thereof having a cloud point are not yet known at all, and therefore, copolymers and / or salts having a cloud point in a limited temperature range of 30 to 70 ° C. Its existence was completely unknown. In addition, even though such copolymers and / or salts thereof are water-soluble, they have not been known to form a hydrophobic film after use and are suitable for hair styling and the like. Therefore, such copolymers and / or salts thereof have not been incorporated into cosmetics such as cosmetics for hair styling.

[0004]

DISCLOSURE OF THE INVENTION The present invention has been made under such a circumstance, and a copolymer and / or a salt thereof which is water-soluble and forms a hydrophobic film after use is disclosed. An object of the present invention is to provide a cosmetic that is useful for hairdressing and the like.

[0005]

SUMMARY OF THE INVENTION In view of such circumstances, the present inventors have found that a copolymer and / or a salt thereof which is water-soluble and forms a hydrophobic film after use is contained.
In pursuit of cosmetics useful for hair styling and the like, as a result of intensive research efforts, copolymers having derivatives of acrylic acid and methacrylic acid as constituent monomers have a hydrophilic group and a lipophilic group in the same molecule, and Heating the aqueous carrier solution of the copolymer and / or salt thereof above the cloud point, characterized by having a cloud point at 70 ° C., is found to release the copolymer and form a hydrophobic film; I got the idea of the solution. Furthermore, as a result of detailed examination,
The copolymer is contained in a cosmetic such as a hairdressing agent, and after treating the hair and the like, by heating and drying with a dryer,
The inventors found that a film having excellent hydrophobicity was formed, and completed the invention. That is, the present invention relates to the following technology. (1) A copolymer comprising a derivative of acrylic acid and methacrylic acid as a constituent monomer, wherein the copolymer has a hydrophilic group and a lipophilic group in the same molecule, and has a cloud point at 30 to 70 ° C. And / or a salt thereof. (2) The copolymer and / or salt thereof according to (1), wherein the average molecular weight is 5,000 to 300,000 in terms of polyethylene in a gel filtration (GPC) column. (3) The copolymer according to (1) or (2), wherein the hydrophilic group is a polyoxyalkylene group.
Or a salt thereof. (4) for use in cosmetics, (1) to
(3) The copolymer according to any one of the above and / or a salt thereof. (5) The copolymer and / or salt thereof according to (4), wherein the cosmetic is subjected to a drying and heating step when used. (6) A cosmetic, comprising one or more selected from the copolymers and salts thereof according to any one of (1) to (5). (7) The cosmetic according to (6), which is used for hair. (8) The cosmetic according to (6) or (7), which is used in a method of use including a drying and heating step. (9) The cosmetic according to any one of (1) to (5), wherein the cosmetic according to any one of (6) to (8) is applied, and thereafter the cosmetic contains the cosmetic and / or a salt thereof. A method for treating a living body surface, comprising precipitating the copolymer according to any one of claims 1 to 5 and / or a salt thereof on the living body surface through a heating step at or above the cloud point. (10) The method for treating a living body surface according to (9), wherein the treatment is hair styling. Hereinafter, the present invention will be described in detail focusing on embodiments.

[0006]

BEST MODE FOR CARRYING OUT THE INVENTION (1) Copolymer of the present invention The copolymer of the present invention is a copolymer containing a derivative of acrylic acid and methacrylic acid as a constituent monomer, having a hydrophilic group and a lipophilic group in the same molecule, It has a cloud point at 30 to 70 ° C. Here, as a derivative of acrylic acid or methacrylic acid, those having a lipophilic group include n-butyl acrylate, n-butyl methacrylate, isobutyl acrylate, isobutyl methacrylate, tert-butyl acrylate, tert-butyl methacrylate, isoamyl acrylate, isoamyl Methacrylate, n-hexyl acrylate, n-hexyl methacrylate, cyclohexyl acrylate, cyclohexyl methacrylate, n-octyl acrylate, n-octyl methacrylate, 2-ethylhexyl acrylate, 2-ethylhexyl methacrylate,
Preferable examples include alkyl esters such as benzyl acrylate, benzyl methacrylate, dodecyl acrylate, dodecyl methacrylate, stearyl acrylate and stearyl methacrylate, and those having a hydrophilic group include polyoxyethylene or polyoxypropylene adducts. Preferred examples include an alkyl ether or an acyl ester of an adduct. As the content of such a monomer, one or two or more selected from monomers having a lipophilic group in a total amount of 1 to 40% by weight,
More preferably, it contains 3 to 30% by weight as a constituent monomer, and one or two or more kinds selected from monomers having a hydrophilic group in a total amount of 30 to 70% by weight, more preferably,
It contains 35 to 65% by weight as a constituent monomer. By controlling the ratio of the constituent monomer having a hydrophilic group to the constituent monomer having a lipophilic group in such a ratio, the cloud point can be kept within the above-mentioned 30 to 70 ° C. In the copolymer of the present invention having a cloud point of 30 to 70 ° C. and / or a salt thereof, monomers commonly used in copolymers other than the above-mentioned constituent monomers are used as constituent monomers within a range that does not impair the effects of the present invention. And can be contained.
Examples of such an optional constituent monomer include esters of acrylic acid with an alcohol having 3 or less carbon atoms, such as acrylic acid, methacrylic acid, methyl acrylate, ethyl acrylate, n-propyl acrylate, and isopropyl acrylate; Esters of methacrylic acid with alcohols having 3 or less carbon atoms such as methyl, ethyl methacrylate, n-propyl methacrylate, and isopropyl methacrylate; acrylic acid such as 2-hydroxyethyl acrylate, 4-hydroxybutyl acrylate, and hydroxypropyl acrylate Hydroxyalkyl esters, hydroxyalkyl esters of methacrylic acid such as 2-hydroxyethyl methacrylate, hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, vinyl acetate, vinyl alcohol, vinyl alcohol Alkyl ethers of Le, styrene,
Examples include α-alkylstyrene, butadiene, isoprene, propene, vinyl chloride, acrylonitrile and the like.
The copolymer of the present invention can be produced by treating these monomers according to a conventional method. That is, after dissolving the monomer in a solvent and the like, adding a polymerization initiator and the like,
What is necessary is just to heat. The polymerization initiator can be used without any particular limitation as long as it is generally used.For example, peroxides such as benzoyl peroxide, azobisisobutyronitrile, etc. The polymerization may be started using a suitable azo compound, a persulfate, a persulfate and a sulfite (redox-based initiator), or the like. Since the copolymer of the present invention has water solubility, if the solvent is miscible with water, it can be concentrated as it is, or if the solvent is immiscible with water, after the reaction, water can be added and flushed. The copolymer migrates towards the water. Thereafter, the aqueous phase is removed and concentrated to obtain the copolymer of the present invention. As used herein, the term "water-soluble" refers to the solubility in water. Specifically, when a uniform system is prepared by adding 99 parts by weight of water to 1 part by weight of a copolymer, the transmittance of the liquid to visible light is determined. Is 90% or more. The copolymer of the present invention may be a random type copolymer, a graft type copolymer, a block type or a combination thereof. When acrylic acid or methacrylic acid is contained as a constituent monomer in these copolymers, an alkali metal such as sodium or potassium, an alkaline earth metal such as calcium or magnesium, ammonium,
It can also be used as a salt with an organic amine for private use. The copolymer thus obtained not only has water solubility, but also has a cloud point.When an aqueous solution is applied to hair or the like and heated with a drier or the like, the heating causes the copolymer to reach a temperature higher than the cloud point and precipitates. It has the property of forming a coating. Further, by having a hydrophilic group and a lipophilic group, such a film has plasticity even without a plasticizer. In addition, since it has water solubility as described above, water can be used as a solvent in formulating, and a composition can be prepared in a dosage form in which an organic solvent such as ethanol is considerably reduced. Therefore, it is particularly preferably used for hair cosmetics such as hair styling, and is formulated with an aqueous carrier containing water as a main component and containing about 10% by weight of a polyhydric alcohol, ethanol or the like, and is rapidly prepared under the use of a dryer. In addition to being suitably applied as a hair styling agent for forming a hydrophobic film, it can be added to cosmetics such as skin cosmetics and nail cosmetics for the purpose of forming a protective film on the skin surface, and can be fixed with a heat gun or the like. It can also be used as a surface treatment agent for paint, metal, glass, fiber and the like. At present, there is no known substance capable of forming a hydrophobic and plastic film after drying by heating at a temperature higher than the cloud point and forming a film. In the copolymer of the present invention, the number average molecular weight in terms of polyethylene measured by GPC (gel permeation chromatography) is preferably 5,000 to 300,000, more preferably 70 to 300,000.
00 to 250,000. This is because film properties may be impaired even if it is smaller or larger than this range.

(2) Cosmetic of the Present Invention The copolymer of the present invention is particularly suitably applied to the field of cosmetics. This is because the feature of the copolymer of the present invention is that it has a cloud point and thus forms a hydrophobic film by a treatment such as a drier, which is suitable for an application requiring such a treatment. Furthermore, a plastic film is formed even without a plasticizer, and the hydrophobic property of the film is particularly suitable for cosmetics in which endocrine disrupting substances must be avoided. In view of this, it is particularly preferable to apply the present invention to cosmetics for hair using a dryer. In the cosmetic of the present invention, the copolymer is a hairdressing agent for shaping the shape of hair,
For make-up cosmetics, etc., to prevent moisture from escaping from the skin, etc., as a protective film for the skin, or to prevent the make-up applied on the skin from being destroyed by physical force such as sebum or wind. It has a function as a fixing medium such as a coloring material. As a specific example,
For example, basic cosmetics such as creams, emulsions, lotions, and packs, make-up cosmetics such as nail colors, lip colors, mascaras, eyeliners, foundations, and under makeups, hair liquids, set lotions, hair colors, and hair mascaras Examples of the cosmetics for the hair include, for example, cosmetics for the hair which do not contain an organic solvent such as ethanol or a liquefied gas such as natural gas or Freon gas. In the cosmetic of the present invention, the copolymer may contain only one kind or two or more kinds in combination. The preferred content of the copolymer in the cosmetic of the present invention is 0.01 to 30% by weight, and more preferably 0.1 to 15% by weight.

[0008] The cosmetic of the present invention may contain, in addition to the above-mentioned copolymer, which is an essential component, optional components usually used in cosmetics. Such optional components include, for example, hydrocarbons such as squalane, petrolatum, microcrystalline wax, jojoba oil, carnauba wax, esters such as octyldodecyl oleate,
Triglycerides such as olive oil, beef tallow, and coconut oil; fatty acids such as stearic acid, oleic acid, and ritinoleic acid;
Higher alcohols such as oleyl alcohol, stearyl alcohol and octyl dodecanol; anionic surfactants such as sulfosuccinates and sodium polyoxyethylene alkyl sulfate; amphoteric surfactants such as alkyl betaine salts; cationic interfaces such as dialkyl ammonium salts. Activators, sorbitan fatty acid esters, fatty acid monoglycerides, nonionic surfactants such as polyoxyethylene adducts, polyoxyethylene alkyl ethers, polyoxyethylene fatty acid esters, etc., polyethylene glycol, glycerin, 1,3-butanediol And the like, a thickening / gelling agent, an antioxidant, an ultraviolet absorber, a coloring material, a preservative, a powder, and the like. Of these, it should be particularly noted that in such a dosage form, an organic solvent such as ethanol must be used as a vehicle for the copolymer in an amount of 40% by weight. However, since the copolymer of the present invention is water-soluble, 10% by weight is required. %. The cosmetic of the present invention is produced by treating these optional components and essential components according to a conventional method.

[0009]

EXAMPLES Hereinafter, the present invention will be described in more detail with reference to Examples, but it goes without saying that the present invention is not limited to only such Examples.

Example 1 Production Example 1 28.0 g of methoxypolyethylene glycol (9) acrylate was placed in a flask equipped with a cooler, a stirrer, and a nitrogen inlet tube.
12.0 g of n-octyl acrylate and 80 ethyl acetate
A mixed solvent of 80 ml of ethanol and 80 ml of ethanol was taken and mixed with stirring. Then, 0.2 g of benzoyl peroxide was added to a mixed solvent of 10 m.
After adding the solution dissolved in 1 liter, the mixture was sufficiently replaced with a nitrogen stream while stirring was continued. Polymerization was carried out at the boiling point of the solvent for 8 hours. After the completion of the reaction, the mixed solvent was flushed with water to obtain an aqueous solution of the polymer. This was freeze-dried to obtain Copolymer 1. Its cloud point and molecular weight were measured. The confirmation of the cloud point was performed according to the following method. That is, a 5 wt% aqueous solution of the copolymer is heated at a predetermined temperature for 30 minutes, and it is observed whether the polymer undergoes phase separation from the solution. The temperature at which the polymer was insolubilized by phase separation was taken as the cloud point. The molecular weight was measured according to the following method. That is, acrylonitrile 30 v% is added to a 20 mM aqueous solution of potassium hydrogen phosphate.
The mixed solution to which To was added was used as the eluent, and Tosoh Corporation TSK-
It was measured as a molecular weight in terms of polyethylene by GPC using GEL PW series as a column. The cloud point of Copolymer 1 was 70 ° C. and the molecular weight was 9000. Thus, this copolymer 1 was identified as the copolymer of the present invention.

Example 2 Production Example 2 Methoxy polyethylene glycol (23) methacrylate 30.0 was placed in a flask equipped with a cooler, a stirrer, and a nitrogen inlet tube.
g, 12.0 g of cyclohexyl methacrylate, 18.0 g of 2hydroxyethyl methacrylate, 80 ml of ethanol, and 60 ml of water were mixed with stirring.
A solution of 0.5 g of ammonium persulfate dissolved in 10 ml of water was added thereto, and the mixture was sufficiently replaced with a nitrogen stream while stirring was continued. The polymerization was carried out by heating to 80 ° C. for 12 hours. After the completion of the reaction, the pH was adjusted to 7.0 with an aqueous sodium hydroxide solution.
Then, ethanol was removed to obtain an aqueous solution of a polymer. This was freeze-dried to obtain Copolymer 2. The cloud point was 50 ° C. and the average molecular weight was 40,000. Thus, this copolymer 2 was identified as the copolymer of the present invention.

Example 3 Production Example 3 Methoxypolyethylene glycol (23) methacrylate 24.0 was placed in a flask equipped with a cooler, a stirrer, and a nitrogen inlet tube.
g, 2 ethylhexyl methacrylate 9.0 g, 2 hydroxyethyl methacrylate 12.0 g, methyl methacrylate 15.0 g and isopropyl alcohol 180
ml, commercially available standard neutral phosphate buffer solution (pH 6.86) 1
20 ml of the mixed solvent was taken and mixed with stirring. A solution of 1.0 g of ammonium persulfate dissolved in 10 ml of water was added thereto, and the mixture was sufficiently replaced with a nitrogen stream while stirring was continued. The polymerization was carried out by heating to 65 ° C. for 16 hours. After completion of the reaction, 1.8 g of calcium hydroxide was added to the reaction system, and the mixture was stirred at 65 ° C for 2 hours. After removing the powder by filtration, isopropyl alcohol was removed to obtain an aqueous solution of the polymer.
This was freeze-dried to obtain Copolymer 3. When the cloud point of this product was measured, it was 40 ° C., and the average molecular weight was 600.
00. This confirmed that the copolymer was the copolymer of the present invention.

Example 4 Production Example 4 48.0 g of polyethylene glycol (23) monoacrylate was placed in a flask equipped with a cooler, a stirrer and a nitrogen inlet tube, and
Hexyl methacrylate 8.0 g, n-butyl methacrylate 8.0 g, 2-hydroxyethyl methacrylate 1
6.0 g, ethyl alcohol 160 ml, water 60 m
1 mixed solvent was taken and mixed with stirring. Thereafter, the mixture was sufficiently replaced with a nitrogen stream while continuing stirring, and after heating to 65 ° C., a solution in which 1.5 g of potassium persulfate was dissolved in 10 ml of water and a solution in which 1.5 g of sodium bisulfite was dissolved in 10 ml of water were added. The polymerization was carried out for 10 hours while maintaining the temperature at 65 ° C.
After the completion of the reaction, the pH was adjusted to 7.0 with an aqueous sodium hydroxide solution, and then ethanol was removed to obtain an aqueous polymer solution. This was freeze-dried to obtain Copolymer 4. It had a cloud point of 60 ° C. and an average molecular weight of 120,000, indicating that the copolymer was a copolymer of the present invention.

Example 5 Production Example 5 Methoxy polyethylene glycol (23) monomethacrylate 4 was placed in a flask equipped with a cooler, a stirrer, and a nitrogen inlet tube.
0.0 g, dodecyl methacrylate 4.8 g, 2hydroxyethyl methacrylate 20.0 g, ethyl methacrylate 15.2 g, and isopropyl alcohol 150 m
1, commercially available standard acid phthalate buffer (pH 4.01) 10
0 ml of the mixed solvent was taken and mixed with stirring. After a solution of 0.7 g of ammonium persulfate dissolved in 10 ml of water was added thereto, the mixture was sufficiently replaced with a nitrogen stream while stirring was continued.
The polymerization was carried out by heating to 80 ° C. for 12 hours. After the completion of the reaction, the pH was adjusted to 7.0 with an aqueous sodium hydroxide solution, and then ethanol was removed to obtain an aqueous polymer solution. This was freeze-dried to obtain Copolymer 5. Its cloud point is 55 ℃
And the average molecular weight was 80,000.

Example 6 Production Example 6 39.0 g of polyethylene glycol (9) monomethacrylate, 9.0 g of isoamyl methacrylate, 9.0 g of methyl methacrylate, 3.0 g of styrene were placed in a flask equipped with a cooler, a stirrer and a nitrogen inlet tube. Ethyl acetate 80m
and a mixed solvent of 60 ml of isopropyl alcohol, and stirred and mixed. A solution prepared by dissolving 0.2 g of 2,2-azobis (isobutyronitrile) in 10 ml of a mixed solvent was added thereto, and the mixture was sufficiently replaced with a nitrogen stream while stirring was continued. Polymerization was carried out for 16 hours at the boiling point of the solvent. After completion of the reaction, the mixed solvent was removed by evaporation to obtain Copolymer 6. It had a cloud point of 60 ° C. and an average molecular weight of 10,000, indicating that the copolymer was a copolymer of the present invention.

Example 7 Production Example 7 20.0 g of polyethylene glycol (23) monomethacrylate was placed in a flask equipped with a cooler, a stirrer and a nitrogen inlet tube.
Methoxytripropylene glycol methacrylate 1
A mixed solvent of 0.0 g, 5.0 g of n-hexyl methacrylate, 10.0 g of methyl methacrylate, 5.0 g of vinyl acetate, 180 ml of methanol and 70 ml of water was taken and mixed. 0.5 g of potassium persulfate and 10 ml of water
After the addition of the solution dissolved in, the mixture was sufficiently replaced with a nitrogen stream while stirring was continued. The polymerization was carried out by heating to 80 ° C. for 6 hours. After completion of the reaction, the pH was adjusted to 7.0 with an aqueous sodium hydroxide solution.
After adjusting to 0, methanol was removed to obtain an aqueous solution of the polymer. This was freeze-dried to obtain Copolymer 7. It has a cloud point of 45 ° C. and an average molecular weight of 200,000
Met. This proved that this copolymer was the copolymer of the present invention.

Example 8 Production Example 8 A methoxypolyethylene glycol (23) acrylate 20.0 was placed in a flask equipped with a cooler, a stirrer, and a nitrogen inlet tube.
g, 8.0 g of isobutyl acrylate, 12.0 g of 2hydroxyethyl acrylate, and 90 ml of isopropyl alcohol, a commercially available standard neutral phosphate buffer solution (pH 6.0).
86) 60 ml of the mixed solvent was taken and mixed with stirring. A solution of 1.0 g of ammonium persulfate dissolved in 10 ml of water was added thereto, and the mixture was sufficiently replaced with a nitrogen stream while stirring was continued. The polymerization was carried out by heating to 70 ° C. for 16 hours. After completion of the reaction, the pH was adjusted to 7.0 with an aqueous sodium hydroxide solution, and then isopropyl alcohol was removed to obtain an aqueous solution of a polymer. This was freeze-dried to obtain Copolymer 8. This has a cloud point of 60 ° C. and an average molecular weight of 20,000
Met. Thus, the copolymer was identified as the copolymer of the present invention.

Example 9 Production Example 9 27.0 g of methoxypolyethylene glycol (9) acrylate was placed in a flask equipped with a cooler, a stirrer, and a nitrogen inlet tube.
3.0 g of 2-ethylhexyl acrylate, 18.0 g of 4-hydroxybutyl methacrylate, 12.0 g of isopropyl acrylate and 240 m of isopropyl alcohol
1 and mixed with stirring. Add benzoyl peroxide 0.5
g was dissolved in 10 ml of isopropyl alcohol, and the mixture was sufficiently replaced with a nitrogen stream while stirring. Polymerization was carried out for 16 hours at the boiling point of the solvent. After completion of the reaction, isopropyl alcohol was removed to obtain Copolymer 9. It has a cloud point of 50 ° C. and an average molecular weight of 11,000.
Met. Thus, this copolymer was identified as the copolymer of the present invention.

Example 10 Production Example 10 Methoxypolyethylene glycol (9) methacrylate 36.0 was placed in a flask equipped with a cooler, a stirrer, and a nitrogen inlet tube.
g, n-butyl acrylate 9.0 g, methyl methacrylate 15.0 g and isopropyl alcohol 180 m
1, commercially available standard neutral phosphate buffer solution (pH 6.86) 12
0 ml of the mixed solvent was taken and mixed with stirring. A solution of 1.0 g of ammonium persulfate dissolved in 10 ml of water was added thereto, and the mixture was sufficiently replaced with a nitrogen stream while stirring was continued.
The polymerization was carried out for 14 hours by heating to 65 ° C. After completion of the reaction, 1.8 g of calcium hydroxide was added to the reaction system, and the mixture was stirred at 65 ° C for 2 hours. After removing the powder by filtration, isopropyl alcohol was removed to obtain an aqueous solution of the polymer. This was freeze-dried to obtain Copolymer 10. Its cloud point was 65 ° C and average molecular weight was 30,000. Thus, the copolymer was identified as the copolymer of the present invention.

Example 11 Production Example 11 A methoxypolyethylene glycol (23) methacrylate 24.0 was placed in a flask equipped with a cooler, a stirrer, and a nitrogen inlet tube.
g, n-hexyl acrylate 6.0 g, 2-hydroxyethyl methacrylate 12.0 g, methyl methacrylate 18.0 g and isopropyl alcohol 180 ml, commercially available standard neutral phosphate buffer solution (pH 6.86) 120 ml
And mixed with stirring. A solution of 1.0 g of ammonium persulfate dissolved in 10 ml of water was added thereto, and the mixture was sufficiently replaced with a nitrogen stream while stirring was continued. 70 ° C
And the polymerization was carried out for 16 hours. After completion of the reaction, the pH was adjusted to 7.0 with an aqueous sodium hydroxide solution, and then isopropyl alcohol was removed to obtain an aqueous solution of a polymer. This was freeze-dried to obtain copolymer 11. Its cloud point was 45 ° C and average molecular weight was 30,000. Thus, the copolymer was identified as the copolymer of the present invention.

Comparative Example 1 Production Example 12 Methoxypolyethylene glycol (23) methacrylate 15.0 was placed in a flask equipped with a cooler, a stirrer, and a nitrogen inlet tube.
g, 24.0 g of n-hexyl acrylate, 21.0 g of 2-hydroxyethyl methacrylate, and 180 ml of isopropyl alcohol, a commercially available standard neutral phosphate buffer solution (p
H6.86) 120 ml of a mixed solvent was taken and mixed by stirring. A solution of 1.0 g of ammonium persulfate dissolved in 10 ml of water was added thereto, and the mixture was sufficiently replaced with a nitrogen stream while stirring was continued. The polymerization was carried out by heating to 70 ° C. for 16 hours. After completion of the reaction, the pH was adjusted to 7.0 with an aqueous sodium hydroxide solution.
After adjusting to 0, isopropyl alcohol was removed to obtain an aqueous solution of the polymer. This is freeze-dried and copolymer 1
2 was obtained. The cloud point was 20 ° C. and the average molecular weight was 15,000. This confirmed that the copolymer was not a copolymer of the present invention.

Comparative Example 2 Production Example 13 Methoxy polyethylene glycol (23) methacrylate 51.0 was placed in a flask equipped with a cooler, a stirrer, and a nitrogen inlet tube.
g, 9.0 g of n-hexyl acrylate, 180 ml of isopropyl alcohol, and 120 ml of a commercially available standard neutral phosphate buffer solution (pH 6.86) were mixed with stirring. 1.0 g of ammonium persulfate was added to 10 ml of water.
After the addition of the solution dissolved in, the mixture was sufficiently replaced with a nitrogen stream while stirring was continued. The polymerization was carried out by heating to 70 ° C. for 16 hours. After completion of the reaction, the pH was adjusted to 7.0 with an aqueous sodium hydroxide solution, and then isopropyl alcohol was removed to obtain an aqueous solution of a polymer. This was freeze-dried to obtain copolymer 13. The cloud point was 80 ° C. and the average molecular weight was 70,000. This confirmed that the copolymer was not the copolymer of the present invention.

Comparative Example 3 Production Example 14 42.0 g of methacrylic acid, 9.0 g of n-hexyl acrylate, 9.0 g of 2-hydroxyethyl methacrylate, and 180 ml of isopropyl alcohol were placed in a flask equipped with a cooler, a stirrer, and a nitrogen inlet tube. A mixed solvent of 120 ml of a neutral phosphate buffer solution (pH 6.86) was taken and mixed with stirring. 1.0 g of ammonium persulfate was added to 10 m of water.
After adding the solution dissolved in 1 liter, the mixture was sufficiently replaced with a nitrogen stream while stirring was continued. The polymerization was carried out by heating to 70 ° C. for 16 hours. After completion of the reaction, the pH was adjusted to 7.0 with an aqueous sodium hydroxide solution, and then isopropyl alcohol was removed to obtain an aqueous solution of a polymer. This was freeze-dried to obtain Copolymer 14. It did not have a cloud point and had an average molecular weight of 10,000. It was identified as not a copolymer according to the invention.

Water Resistance Test A 10% by weight aqueous solution of the above copolymers 1 to 14 was prepared, and 1 g was uniformly applied to 10 g of the hair bundle. After the application, the sample was dried with hot air under ordinary dryer conditions.
Each sample was run in running water for 3 minutes, air-dried, and then ATR
Residuality was measured by -IR based on the difference in peak intensity of expansion and contraction of methylene before and after running water treatment. Table 1 shows the results. This shows that all of the copolymers having a cloud point of the present invention have excellent water resistance. Furthermore, it can be seen that the copolymer of the present invention has particularly excellent properties because it is a uniform aqueous solution at the time of application, and forms a hydrophobic film by a drier treatment and is suitably fixed to hair.

[0025]

[Table 1]

<Example 16> Using the above copolymers 1 to 14, a test was conducted on the detergency of the hand-held copolymer. That is, a 10% by weight aqueous solution of each copolymer was prepared, 0.1 ml was attached to a hand, gently rubbed, and flushed with running water. Then, gently wipe your hands with a towel to remove any remaining feeling.
No remaining feeling, Δ: Somewhat remaining feeling, ×: Judgment based on clear criteria for remaining feeling. Table 2 shows the results. This shows that any of the copolymers of the present invention can be easily washed with water without drying.

[0027]

[Table 2]

Example 17 According to the following formulation,
A hairdressing cosmetic was created. That is, the prescription components were heated and solubilized at 80 ° C., and were stirred and cooled to obtain a cosmetic composition for hairdressing. This was filled into a container having a nozzle for spraying to prepare a hairdressing composition. This was evaluated by a specialized panel. The time points for evaluation were immediately after hair styling and 4 hours after hair styling. The evaluation criteria were ：: good, Δ: somewhat good, ×: bad.
Table 4 shows the results. It can be seen that the hairdressing composition of the present invention is excellent in the action of maintaining excellent hairdressing power for a long time. It is also found that the present invention can reduce the amount of ethanol used as an organic solvent to 10% by weight. Copolymer * 10 parts by weight Ethanol 10 parts by weight Dimethicone 0.5 parts by weight POE (20) cetyl ether 0.3 parts by weight POE (9) lauryl ether 0.7 parts by weight 0.5 parts by weight 1,3-butanediol Water 70 Parts by weight * Details are shown in Table 3.

[0029]

[Table 3]

Example 18 According to the following formulation,
A lotion as the cosmetic of the present invention was prepared. With respect to these lotions, the amount of dissipated water was measured, and those classified as 20% or more suppressed were marked with ○, those with 10% or more but less than 20%, and those with less than 10% were marked with X. Table 4 shows the results. Each of these lotions was excellent in water retention. Copolymer ** 1 part by weight 1,3-butanediol 5 parts by weight Ethanol 5 parts by weight Water 89 parts by weight ** Table 4 shows details.

[0031]

[Table 4]

[0032]

According to the present invention, there is provided a copolymer which is water-soluble and forms a hydrophobic film after use, and / or a salt thereof, and a cosmetic composition containing the same, which is useful for hair styling. You can do it.

Continued on the front page F term (reference) 4C083 AB052 AC102 AC122 AC182 AD091 AD092 AD152 CC01 CC02 CC28 CC31 CC32 DD27 DD31 EE03 EE11 EE28 FF04 4J100 AB02R AC03R AD02R AG04R AJ02R AL02Q AL02R AL03Q AL04Q AL05Q08P04 DA09 DA61 JA61

Claims (10)

[Claims] 1. A copolymer comprising a derivative of acrylic acid and methacrylic acid as a constituent monomer, having a hydrophilic group and a lipophilic group in the same molecule, and having a cloud point at 30 to 70 ° C. , Copolymers and / or salts thereof. 2. The copolymer and / or salt thereof according to claim 1, wherein the average molecular weight is 5,000 to 300,000 in terms of polyethylene in a gel filtration (GPC) column. 3. The copolymer according to claim 1, wherein the hydrophilic group is a polyoxyalkylene group and / or a salt thereof. 4. The copolymer and / or salt thereof according to claim 1, which is used for cosmetics. 5. The copolymer and / or salt thereof according to claim 4, wherein the cosmetic is subjected to a drying and heating step when used. 6. A cosmetic comprising at least one selected from the copolymer according to claim 1 and a salt thereof. 7. The cosmetic according to claim 6, which is used for hair. 8. The cosmetic according to claim 6, wherein the cosmetic is used in a use method including a drying and heating step. 9. The cosmetic according to claim 6, which is applied, and thereafter the cosmetic contains the cosmetic.
Precipitation of the copolymer and / or salt thereof according to any one of claims 1 to 5 on a living body surface through a heating step at or above the cloud point of the copolymer and / or salt thereof according to any one of claims 1 to 5. A method for treating a living body surface, which is characterized by the following. 10. The method for treating the surface of a living body according to claim 9, wherein the treatment is hair styling.