N-[7-(HYDROXY-.KAPPA.O)-8-[[2-(HYDROXY-.KAPPA.O)-5-(METHYLSULFONYL)PHENYL]AZO-.KAPPA.N1]-1-NAPHTHALENYL]ACETAMIDATO(2-)][2-(HYDROXY-.KAPPA.O)-3-[[2-(HYDROXY-.KAPPA.O)-1-NAPHTHALENYL]AZO-.KAPPA.N1]-5-NITROBENZENESULFONATO(3-)]-CHROMATE(2-) DISODIUM