3,3'-[Carbonylbis[imino(2-methyl-4,1-phenylene)-2,1-diazenediyl]]bis-1,5-naphthalenedisulfonic Acid Sodium Salt (Technical Grade)

3,3'-[Carbonylbis[imino(2-methyl-4,1-phenylene)-2,1-diazenediyl]]bis-1,5-naphthalenedisulfonic Acid Sodium Salt (Technical Grade)