Amino acid-modified organopolysiloxane, making method, and cosmetics

1. An amino acid-modified organopolysiloxane having a backbone comprising organosiloxane segments, wherein an organic group having the general formula (1) is bonded to at least one silicon atom in the organosiloxane segments,

wherein X and Y are each independently a divalent C 1 -C 10 hydrocarbon group, m is an integer of 0 to 4, R a is hydrogen or a monovalent C 1 -C 4 hydrocarbon group, and Z is an organic group having the general formula (2):

wherein R b is a side chain of an amino acid, le is hydrogen or C 1 -C 6 alkyl, and R d is hydrogen or C 1 -C 6 alkyl.

2. The amino acid-modified organopolysiloxane of claim 1 , having the general formula (3):

wherein R is each independently selected from the group consisting of hydrogen, hydroxyl, C 1 -C 3 alkoxy, C 1 -C 30 alkyl, C 1 -C 30 fluoroalkyl, C 6 -C 30 aryl, and C 7 -C 30 aralkyl,

R 10 is an organic group having formula (1),

R 11 is an organic group selected from the group consisting of R and R 10 ,

A is a segment having the general formula (4):

wherein R and R 10 are as defined above, and Q is an oxygen atom or a divalent C 1 -C 3 hydrocarbon group,

the subscripts a, b, and c are each independently an integer of 0 to 3, e is an integer of 0 to 100, f is an integer of 0 to 5,000, g is 0 or 1, h is 0 or 1, i is an integer of 0 to 100, j is an integer of 0 to 5,000, satisfying 1≦a+b+c+e+g+i when R 11 is R 10 , and 1≦a+b+c+e+i when R 11 is R.

3. The amino acid-modified organopolysiloxane of claim 1 , wherein the amino acid is selected from the group consisting of alanine, arginine, asparagine, aspartic acid, cysteine, glutamine, glutamic acid, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, sarcosine, γ-aminobutyric acid, ornithine, creatine, opine, cystine, hydroxyproline, hydroxylysine, thyroxine, O-phosphoserine, and valine.

4. A method for preparing the amino acid-modified organopolysiloxane of claim 1 ,

said method comprising reacting an amino-modified organopolysiloxane with an amino acid or amino acid derivative ester in the presence of an organometallic catalyst,

said amino-modified organopolysiloxane having a backbone comprising organosiloxane segments wherein an amino group having the general formula (5):

wherein X, Y, m, and R a are as defined for the general formula (1) is bonded to at least one silicon atom in the organosiloxane segments,

said amino acid or amino acid derivative ester being an amino acid or amino acid derivative whose carboxyl group has been esterified and having the general formula (6):

wherein R′ is a monovalent C 1 -C 7 hydrocarbon group, and R b , R c , and R d are as defined for the general formula (2).

5. The method of claim 4 wherein

said amino-modified organopolysiloxane has the general formula (7):

wherein R is each independently selected from the group consisting of hydrogen, hydroxyl, C 1 -C 3 alkoxy, C 1 -C 30 alkyl, C 1 -C 30 fluoroalkyl, C 6 -C 30 aryl, and C 7 -C 30 aralkyl,

R 12 is an organic group having formula (5),

R 13 is an organic group selected from the group consisting of R and R 12 ,

A 1 is a segment having the general formula (8):

wherein R and R 12 are as defined above, and Q is an oxygen atom or a divalent C 1 -C 3 hydrocarbon group,

the subscripts a1, b1, and c1 are each independently an integer of 0 to 3, e1 is an integer of 0 to 100, f is an integer of 0 to 5,000, g1 is 0 or 1, h1 is 0 or 1, i1 is an integer of 0 to 100, j is an integer of 0 to 5,000, satisfying 1≦a1+b1+c1+e1+g1+i1 when R 13 is R 12 , and 1≦a1+b1+c1+e1+i1 when R 13 is R, and

said amino acid-modified organopolysiloxane has the general formula (3):

wherein R is as defined above, R 10 is an organic group having formula (1),

R 11 is an organic group selected from the group consisting of R and R 10 ,

A is a segment having the general formula (4):

wherein R, R 10 and Q are as defined above, and a, b, c, e, f, g, h, i, and j are as defined above.

6. The method of claim 4 , wherein said amino acid or amino acid derivative ester has an ester group selected from the group consisting of methyl, ethyl, propyl, butyl, heptyl, hexyl, and benzyl.

7. The method of claim 4 , wherein said amino acid ester has an amino acid residue which is selected from the group consisting of alanine, arginine, asparagine, aspartic acid, cysteine, glutamine, glutamic acid, glycine, histidine, isoleucine, leucine, lysine, methionine, phenylalanine, proline, serine, threonine, tryptophan, tyrosine, sarcosine, γ-aminobutyric acid, ornithine, creatine, opine, cystine, hydroxyproline, hydroxylysine, thyroxine, O-phosphoserine, and valine residues.

8. The method of claim 4 , wherein said amino acid derivative ester has an amino acid derivative residue which is selected from the group consisting of N-acylamino acid, N-alkylamino acid, and N,N-dialkylamino acid residues.

9. The method of claim 8 , wherein the N-acyl is acetyl, propanoyl, butanoyl, pentanoyl, hexanoyl, benzoyl, lauroyl, or stearoyl.

10. The method of claim 4 , wherein the reaction is conducted in an organic solvent.

11. The method of claim 4 , wherein the reaction is conducted at a temperature of 25° C. to 120° C.

12. The method of claim 4 , wherein the organometallic catalyst comprises a metal atom selected from the elements of Group 4 and Group 13 in the Periodic Table.

13. The method of claim 12 , wherein the organometallic catalyst is a tetraalkoxytitanium, tetraalkoxyzirconium or trialkoxyaluminum.

14. A cosmetic composition comprising the amino acid-modified organopolysiloxane of claim 1 .

15. A cosmetic composition comprising a powder treated with the amino acid-modified organopolysiloxane of claim 1 .