Improvements in the Production of Discharge, or Printing, Effects on Fibre which has been Dyed with Vat Colouring Matters.

摘要

21,052. Badische Anilin & Soda Fabrik. Jan. 31, [Convention date]. Printing.-Discharge effects are obtained on fibre which has been dyed with a vat dye (other than sulphur dyes) by treating it with an organic ammonium compound containing an aralkyl residue, and a reducing-agent other than a hydrosulphite or a formaldehyde hydrosulphite or sulphoxylate; the leuco compound of the dye combines with the aralkyl residue. According to an example, a printing-paste is composed of zinc oxide, glycerine, anthraquinone, the mono-calcium salt of the disulphonic acid of dimethylphenylbenzylammonium hydroxide, grape sugar, caustic soda, and gum thickening. Stannous oxide is also specified as a suitable reducing-agent. Specification 30,505/09 is referred to.