2-Naphthalenesulfonic acid, 6-(((3,6-dichloro-4-pyridazinyl)carbonyl)amino)-4-hydroxy-3-((4-sulfophenyl)azo)- 6-(3,6-Dichloropyridazine-4-carboxamido)-4-hydroxy-3-((p-sulphophenyl)azo)naphthalene-2-sulphonic acid 6694-64-0 EINECS 229-740-4