4,4'-diamino-stilbene-2,2'-disulphonic acid ,dsd acid is mainly used in intermediates of fluorescer and varieties dyes Chemical name:4,4'-diamino-stilbene-2,2'-disulphonic acidStructural ... matter0.25% maxInsoluble matter in alkali0.1% maxMoisture2% maxChroma9°maxChemical name:4,4'-diamino-stilbene-2,2'-disulphonic acid Structural formula:Molecular formula:C14H14N2O6S2Properties: Appearance with ...