disodium 5,6',7-trichloro-4,4'-dimethyl[2,2'-bibenzo[b]thiophene]-3,3'-diyl disulphate

Preparation

(a) in the presence of Pyridine , with Chlorosulfonic acid treatment C.I. Vat Red 2?leuco ; (b) used in Pyridine metal (such as copper, iron, zinc, etc) and Sulfur trioxide source (such as Sulfur trioxide, Chlorosulfonic acid or Methyl chlorosulfonate) processing ?C.I. Vat Red 2. The above two kinds of circumstances are through with alkali, filter out the insoluble,, remove Pyridine and salting-out.

Properties and Applications

bright blue light pink to red colourful blue-ray. Shallow red powder. Soluble in water for blue-ray red, solubility in general. This product has the brittle light. Used for the cotton fabric dyeing, can be in neutral or alkaline bath dyeing dyeing, also can be used for printing of cotton, including direct printing, the printing and dyeing discharge printing. Can also be used for the silk fabric and wool fabric and polyester/cotton blended fabric dyeing.

Standard	Ironing Fastness	Chlorine bleach	Light Fastness	Mercerized	Oxygen bleach	Soaping
						Fading	Stain
ISO	4	5	5	4	4	4-5	5