Vat Brown 5, Solubilised

Preparation

(a) in the presence of Pyridine , with Chlorosulfonic acid treatment C.I. Vat Brown 5 leuco; (b) in the Pyridine with metal (such as copper, iron, zinc, etc) and Sulfur trioxide source (such as Sulfur trioxide, Chlorosulfonic acid or Methyl chlorosulfonate, etc.) processing ?C.I. Vat Brown 5. The above two kinds of situation after alkaline, filter out insolubles, remove Pyridine and salting out.

Properties and Applications

red light brown. Yellow grey powder. Soluble in water, solubility is very small, do not dissolve in Etanol and organic solvent. In concentrated sulfuric acid for yellow green, dilution after olive. Its aqueous solution for brown, under fluorescent light for brilliant purple, the electrolyte sensitive, it is a kind of both light brittle, and the photosensitivity of dye. Mainly used for cotton fabric dyeing and printing, also can undertake silk, wool, viscose, vinylon fabric dyeing and printing. Can be directly printed, resist printing and discharge printing, white discharge effect is good.