Exhaust dyeing process for sulphur dyes
AssigneeClariant Finance (BVI) Limited
InventorMark S. Carlough
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Abstract
Improved processes for the exhaust dyeing of cellulosic fibers with sulphur dyes in the presence of non-sulphide reducing agents wherein the dyeing of the textile substrate is performed in a closed vessel in an atmosphere of reduced oxygen level and then oxidizing.
Claims39
A process for exhaust dyeing cellulosic fibrous material with a sulfur dye, which process comprises contacting the fibrous material with an aqueous dyebath that contains at least one sulfur dye (S) in at least partially soluble form (S.sub.A) and at least one non-sulfide reducing agent (R), in an atmosphere of reduced oxygen level comprising an inert gas in a closed vessel and then oxidizing by treatment with an oxidizing salt in an oxidizing bath, said atmosphere of reduced oxygen level being maintained during exhaustion of the dyebath.
Dependencies are inferred from the claim text.