Synonyms: 2,2'-Stilbenedisulfonicacid,4-(5-sulfo-2H-naphtho[1,2-d]triazol-2-yl)-4'-[[4-(7-sulfo-2H-naphtho[1,2-d]triazol-2-yl)-o-tolyl]azo]-,tetrasodium salt (8CI); 2H-Naphtho[1,2-d]triazole-5-sulfonic acid,2-[4-[2-[4-[[2-methyl-4-(7-sulfo-2H-naphtho[1,2-d]triazol-2-yl)phenyl]azo]-2-sulfophenyl]ethenyl]-3-sulfophenyl]-,tetrasodium salt (9CI)