4-[(4,6-dichloro-1,3,5-triazin-2-yl)amino]-5-hydroxy-6-[[4-[[2-(sulphooxy)ethyl]sulphonyl]phenyl]azo]naphthalene-1,7-disulphonic acid, sodium salt

4-[(4,6-Dichloro-1,3,5-triazine-2-yl)amino]-5-hydroxy-6-[[4-[[2-(sulfooxy)ethyl]sulfonyl]phenyl]azo]-1,7-naphthalenedisulfonic acid/sodium,(1:x) salt