Dual function UV-absorbers for ophthalmic lens materials
View Patent ↗Disclosed are UV absorbers that contain a labile functional group capable of initiating free radical polymerization.
1. A dual function UV absorber of the formula:
where:
A is —CH 3 or —CH 2 CH 3 .
B is —CN, —CO 2 H, —COH, —COCH 3 , —CO 2 CH 3 , —SO 3 H, —CF 3 , or —NO 2 when D is (CH 2 ) n , and —CH 3 or —CH 2 CH 3 when D is nothing.
D is nothing or (CH 2 ) n , n=1-10
E is O or NH, NCH 3 , or NCH 2 CH 3
F is nothing, (CH 2 ) x or (CH 2 CH 2 O) x CH 2 CH 2 where x=1-10.
G is —R, —OR, —NHR, —NRR′, —CO 2 R, or —COR, where R=hydroxyphenylbenzotriazole, and R′=—CH 3 or —CH 2 CH 3 .
2. An ophthalmic lens material comprising a dual function UV absorber of claim 1 .
3. The ophthalmic lens material of claim 2 wherein the dual function UV absorber is present in the ophthalmic lens material in an amount of 1-5% (w/w).
4. The dual function UV absorber of claim 1 wherein R=2-N-(2-hydroxyphenyl)benzotriazole.