Photoprotective and lightfastness-enhancing siloxanes
View Patent ↗Disclosed is a compound of one of the formulae wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , and R 10 each, independently of the others, is an alkyl group, an aryl group, an arylalkyl group, or an alkylaryl group, R 11 and R 12 each, independently of the others, is an alkylene group, an arylene group, an arylalkylene group, or an alkylarylene group, G is a cationic moiety, A is an anionic moiety, n is an integer representing the number of repeat —OSi(R 7 )(R 8 )— monomer units, a is an integer representing the number of repeat —OSi(R 10 )(R 12 -lightfastness moiety)— monomer units, and c is an integer representing the number of repeat —OSi(R 9 )(R 11 -hydrophilic moiety)— monomer units.
1. A compound of the formula
wherein R 1 , R 2 , R 3 , R 4 , R 5 , R 6 , R 7 , R 8 , R 9 , and R 10 each, independently of the others, is an alkyl group, an aryl group, an arylalkyl group, or an alkylaryl group, R 11 and R 12 each, independently of the others, is an alkylene group, an arylene group, an arylalkylene group, or an alkylarylene group, n is an integer representing the number of repeat —OSi(R 7 )(R 8 )— monomer units, a is an integer representing the number of repeat —OSi(R 10 )(R 12 -lightfastness moiety)— monomer units, and c is an integer representing the number of repeat —OSi(R 9 )(R 11 -hydrophilic moiety)— monomer units, wherein the lightfastness moiety is a hydroxybenzophenone group, and wherein the hydrophilic moiety is a polyethylene oxide chain.
2. A compound according to claim 1 wherein the lightfastness moiety is of one of the formulae
3. A compound according to claim 1 wherein the lightfastness moiety is of the formula
4. A compound according to claim 1 wherein the compound is poly(dimethylsiloxane-co-methyl(3-propyl(2-hydroxybenzophenone) siloxane)-graft-methoxypolyethylene glycol).
5. A compound according to claim 1 wherein n is from about 3 to about 100, a is from 1 to about 20, and c is from 1 to about 50.
6. A compound according to claim 1 wherein n is from about 3 to about 50, a is from 1 to about 10, and c is from 1 to about 20.
7. A compound according to claim 1 wherein n is from about 3 to about 20, a is from 1 to about 5, and c is from 1 to about 10.
8. A compound according to claim 1 having a number average molecular weight of from about 1,000 to about 50,000.
9. A compound according to claim 1 having a number average molecular weight of from about 2,000 to about 20,000.
10. A compound according to claim 1 wherein the polyethylene oxide chain has from 1 to about 60 repeat ethylene oxide units.
11. A compound according to claim 1 wherein the polyethylene oxide chain has from 1 to about 30 repeat ethylene oxide units.
12. A compound according to claim 1 wherein the polyethylene oxide chain has from 1 to about 10 repeat ethylene oxide units.
13. A compound according to claim 1 wherein the polyethylene oxide chain has from about 6 to about 30 repeat ethylene oxide units.
14. A compound according to claim 1 wherein the polyethylene oxide chain has from about 9 to about 20 repeat ethylene oxide units.