Development of a new vat dyeing process for cellulose materials pre-treated with Corona

Abstract

Vat dyeing of cellulosic materials is shortened by means of the replacement of preparatory desizing and bleaching operations by a CORONA discharge. The final dye oxidation using alkaline/hydrogen peroxide bath is reinforced in order to get simultaneous effect in the cleaning of the materials. Several vat dyes of different chemical classes were tested either by exhaustion or pad-batch and pad-steam processes and positive evaluation has been made concerning the yield of dyeing, hue and the brightness of the color. Significant economical and ecological benefits are possible in textile wet processing of cellulosic materials.