50814-29-4 Benzenesulfonic acid, 2,2'-(1,2-ethenediyl)bis(5-((4-hydroxy-2-methylphenyl)azo)-, disodium salt Disodium 4,4'-bis((4-hydroxy-2-methylphenyl)azo)stilbene-2,2'-disulphonate EINECS 256-782-0