2-Naphthalenesulfonic acid, 7,7'-(carbonyldiimino)bis(4-hydroxy-3-((2-sulfo-4-((4-sulfophenyl)azo)phenyl)azo)-, potassium sodium salt 7,7'-(Carbonyldiimino)bis(4-hydroxy-3-((2-sulpho-4-((4-sulphophenyl)azo)phenyl)azo)naphthalene-2-sulphonic) acid, potassium sodium salt 83221-51-6 EINECS 280-229-2