Patent ID: 7045177

Claim:
An acenaphtho[1,2-b]quinoxaline sulfoderivative of the general structural formula: wherein: n is an integer in the range of 1 to 4; m is an integer in the range of 0 to 4; z is an integer in the range of 0 to 6 and m+z+n≦10; X and Y are individually selected from the group consisting of CH 3 , C 2 H 5 , OCH 3 , OC 2 H 5 , Cl, Br, OH, OCOCH 3 , NH 2 , NHCOCH 3 , NO 2 , F, CF 3 , CN, OCN, SCN, COOH, and CONH 2 ; M is a counterion; and j is the number of counterions in the molecule, with the proviso that when n=1 and SO 3 — occupies position 1, then m ≠0 or z ≠0.