Water-soluble resin, hair cosmetic material containing the same, and silicone oil adsorption assistant

1. A hair cosmetic material comprising:

a water-soluble resin having a structure corresponding to a copolymer of a monomer mixture comprising a vinylic monomer (A) having a hydroxyl group and an amide bond, and a vinylic monomer (B) having a cationic group,

wherein the vinylic monomer (B) is represented by a formula, CH 2 ═C(R 3 )—CO(O) b —(NH) 1-b —(CH 2 ) c —N + R 4 R 5 R 6 .X − , where R 3 represents a hydrogen atom or a methyl group, R 4 and R 5 each independently represent an alkyl group having 1 to 24 carbon atoms, an aryl group having 6 to 24 carbon atoms, or an aralkyl group having 7 to 24 carbon atoms, R 6 represents a hydrogen atom, an alkyl group having 1 to 24 carbon atoms, an aryl group having 6 to 24 carbon atoms, or an aralkyl group having 7 to 24 carbon atoms, or CH 2 —CH(OH)—CH 2 —N + R 7 R 8 R 9 . Y − , R 7 to R 9 each independently represent an alkyl group having 1 to 24 carbon atoms, an aryl group having 6 to 24 carbon atoms, or an aralkyl group having 7 to 24 carbon atoms, X − and Y − each independently represent an anion, b represents 0 or 1, and c represents an integer from 1 to 10, wherein the water-soluble resin is in a hair cosmetic composition.

2. The hair cosmetic material of claim 1 , wherein the vinylic monomer (A) is hydroxyethyl acrylamide or hydroxyethyl methacrylamide.

3. The hair cosmetic material of claim 1 , wherein the vinylic monomer (B) is at least one selected from the group consisting of meth acroyloxyethyl-trimethylammonium chloride, acroylaminopropyl-trimethylammonium chloride, and meth acroylaminopropyl-trimethylammonium chloride.

4. The hair cosmetic material of claim 1 , wherein the water-soluble resin has a weight average molecular weight of 5,000 to 5,000,000.

5. The hair cosmetic material of claim 1 , wherein the water soluble-resin is capable of forming an aqueous solution having a concentration of at least 5% by weight.

6. The hair cosmetic material of claim 1 , wherein the vinylic monomer (A) is hydroxyethyl acrylamide, and

the vinylic monomer (B) is at least one selected from the group consisting of (meth)acroyloxyethyltrimethylammonium chloride, acroylaminopropyltrimethylammonium chloride, and (meth)acroylaminopropyltrimethylammonium chloride.

7. The hair cosmetic material of claim 1 , further comprising an anionic surfactant.

8. The hair cosmetic material of claim 1 , wherein the water-soluble resin has a concentration of 0.05 to 5% by weight.

9. The hair cosmetic material of claim 8 , further comprising an anionic surfactant at a concentration of 5 to 40% by weight.

10. The hair cosmetic material of claim 1 , wherein the copolymer comprises from 20 to 90% by weight of the structural unit corresponding to the vinylic monomer (A).

11. The hair cosmetic material of claim 1 , wherein the vinylic monomer (A) is represented by a formula, CH 2 ═C(R 1 )—CO—NR 2 —(CH 2 ) 2 —OH, where R 1 represents a hydrogen atom or a methyl group, and R 2 represents a hydrogen atom.

12. The hair cosmetic material of claim 1 , wherein R 4 and R 5 in the formula, CH 2 ═C(R 3 )—CO(O) b —(NH) 1-b —(CH 2 ) c —N + R 4 R 5 R 6 .X − , are each independently a methyl group or an ethyl group, and

R 6 in the formula, CH 2 ═C(R 3 )—CO(O) b —(NH) 1-b —(CH 2 ) c —N + R 4 R 5 R 6 .X − , is a methyl group, an ethyl group or a butyl group.

13. The hair cosmetic material of claim 1 , further comprising silicone oil.

14. The hair cosmetic material of claim 13 , wherein a concentration of the water-soluble resin is controlled to produce a silicone oil adsorption amount on hairs of 70 ppm or more.

15. The hair cosmetic material of claim 13 , wherein a concentration of the water-soluble resin is controlled to produce a silicone oil adsorption amount on hairs of 5,000 ppm or less.

16. The hair cosmetic material of claim 1 , further comprising a cationic surfactant at a concentration of 0.1 to 3% by weight.

17. The hair cosmetic material of claim 1 , further comprising a nonionic surfactant at a concentration of 1 to 10% by weight.

18. The hair cosmetic material of claim 1 , further comprising water.

19. The hair cosmetic material of claim 1 , wherein the vinylic monomer (A) is represented by a formula, CH 2 ═C(R 1 )—CO—NR 2 —(CH 2 ) a —OH, where R 1 represents a hydrogen atom or a methyl group, R 2 represents a hydrogen atom, or an alkyl group or a hydroxyalkyl group having 1 to 4 carbon atoms, and a represents an integer from 1 to 4.

20. The hair cosmetic material of claim 19 , wherein a in the formula is 2.

21. The hair cosmetic material of claim 1 , wherein the monomer mixture comprising the vinylic monomer (A) and the vinylic monomer (B) comprises 20 to 90% by weight of the vinylic monomer (A) and 10 to 80% by weight of the vinylic monomer (B).