3-[[4-[(4-chloro-2-sulphophenyl)azo]-2-methoxy-6-sulpho-1-naphthyl]azo]-4-hydroxy-7-(phenylamino)naphthalene-2-sulphonic acid, sodium salt

3-[[4-[(4-Chloro-2-sulfophenyl)azo]-2-methoxy-6-sulfonaphthalene-1-yl]azo]-4-hydroxy-7-(phenylamino)-2-naphthalenesulfonic acid/sodium,(1:x) salt