1,5-Naphthalenedisulfonic acid, 3,3'-(carbonylbis(imino(2-methyl-4,1-phenylene)azo))bis- 25738-24-3 3,3'-(Carbonylbis(imino(2-methyl-4,1-phenylene)azo))bisnaphthalene-1,5-disulphonic acid 93964-46-6 EINECS 247-220-5