4-hydroxy-7-[[[[5-hydroxy-6-[(2-methyl-4-sulphophenyl)azo]-7-sulpho-2-naphthyl]amino]carbonyl]amino]-3-(phenylazo)naphthalene-2-sulphonic acid, sodium salt

4-Hydroxy-7-[[[[5-hydroxy-6-[(2-methyl-4-sulfophenyl)azo]-7-sulfo-2-naphtyl]amino]carbonyl]amino]-3-(phenylazo)-2-naphthalenesulfonic acid/sodium,(1:x) salt