Patent ID: 7485728

Claim:
A compound of the formula wherein R 1 , R 2 , R 3 , and R 4 each, independently of the others, is (i) a hydrogen atom, (ii) an alkyl group, (iii) an aryl group, (iv) an arylalkyl group, or (v) an alkylaryl group, wherein R 1 and R 2 can be joined together to form a ring, wherein R 3 and R 4 can be joined together to form a ring, and wherein R 1 , R 2 , R 3 , and R 4 can each be joined to a phenyl ring in the central structure; wherein a and b each, independently of the others, is an integer which is 0, 1, 2, or 3, wherein R 5 and R 6 are hydrogen or alkyl; wherein A is an anion selected from the group consisting of Cl − , Br − , I − , HSO 4 − , HSO 3 − , SO 4 2 − , SO 3 2 − , CH 3 SO 3 − , CH 3 C 6 H 4 SO 3 − , NO 3 − , HCOO − , CH 3 COO − , H 2 PO 4 − , HPO 4 2 − , SCN − , BF 4 − , ClO 4 − , SSO 3 − , PF 6 − , and SbCl 6 − ; wherein CA is either a hydrogen atom an alkali metal cation, or a quaternary amine cation of the formula wherein each of R 21 , R 22 , R 23 , and R 24 are independently selected from an alkyl group having 1 to 6 carbon atoms; wherein R is (i) an alkyl group, (ii) an aryl group, (iii) an arylalkyl group, (iv) an alkylaryl group, (v) an alkoxy group, (vi) an acetate group, or (vii) a co-polymer of maleic anhydride; wherein n is an integer which is 1 to 1,000; and wherein m is an integer which is 1 to 1,000.