Process of dyeing using reactive dyes with preliminary bleaching
AssigneeManufacture de Produits Chimiques Protex
InventorJean Balland
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Abstract
The invention relates to a process for dyeing cellulose fibres such as cotton fibres, comprising successively the steps of (a) bleaching the cellulose fibres with an alkaline bath containing aqueous hydrogen peroxide; (b) neutralizing the residual hydrogen peroxide with a reducing agent; and (c) dyeing the cellulose fibres with a reactive dye sensitive to said reducing agent, wherein, after stage (b) and at the latest at the beginning stage (c), any residual agent is neutralized by a quantity of an alkali or alkaline-earth metal halogenite sufficient to neutralize it, whereby it is possible not to perform any intermediate rinsing between stages (a) and (c).
Claims12
A process for dyeing cellulose fibres selected from the group consisting of cotton, linen and rayon comprising successively the stages of (a) bleaching the cellulose fibres with an alkaline bleaching bath containing aqueous hydrogen peroxide;
- (b) neutralizing the residual hydrogen peroxide with a reducing agent selected from the group consisting of thiourea, thiosulfate, hydrosulfite and bisulfite;
- and (c) dyeing, in the presence of an alkaline agent, the cellulose fibres with a dye bath containing a reactive dye sensitive to said reducing agent, in which, after stage (b) and at the latest at the beginning of stage (c), any residual reducing agent is neutralized with an alkali or alkaline-earth metal halogenite.
Dependencies are inferred from the claim text.