Patent ID: 8835671

Claim:
A compound represented by the formula: wherein R 1 and R 2 are independently selected from the group consisting of hydrogen, fluorine, trifluoromethyl, C1-C6 alkyl, and C6-C12 aryl groups; R 3 is selected from the group consisting of C1-C6 alkyl, C6-C12 aryl, CH 2 ═C(R 1 )-L 1 -, and CH 2 ═C(R 2 )-L 2 -; L 1 and L 2 are independently selected from the group consisting of —C(═O)O—(CH 2 ) n — and —C(═O)NH—(CH 2 ) n —, wherein n is an integer from 1 to 20; L 3 is —(CH 2 ) n —, where n is an integer from 1 to 20; A 1 is C, S, SO, P, or PO; X − is the counter ion associated with the N + cationic center; and M + is a counterion associated with the (A 1 =O)O − anionic center.