Method of dyeing wool with acid dyestuffs
AssigneeSandoz Ltd.
InventorsJosef Frauenknecht, Karl Zeller
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Abstract
The invention provides a process for dyeing a textile substrate comprising wool fibres, which process comprises bringing the substrate into contact with an aqueous dyebath containing an acid dyestuff or a mixture of acid dyestuffs having (a) a build-up power on wool of from 90 to 98% at pH 4.5; together with (b) a migrating ability on wool of from 25 to 40%, at pH 4.5; (a) and (b) being determined under specific conditions, in the presence of a levelling agent which is the alkoxylation product of an amine substituted by a fatty saturated or unsaturated residue, the aqueous dyebath containing a mixture of acid dyestuffs when the substrate is a wool/synthetic polyamide fibre blend. These dyestuffs give level, fast and reproducible dyeings of a high quality.
Claims25
A process for dyeing a textile substrate comprising wool fibers, which process comprises bringing the substrate into contact with an aqueous dyebath containing a monosulfonated acid dyestuff or a mixture of monosulfonated acid dyestuffs, said dyestuff or mixture having
- (a) a build up power such that it exhausts onto wool to an extent of 90 to 98% in 60 minutes from a dyebath having a temperature of 98.+-.1.degree. C., a pH of 4.5, a goods:
- liquor ratio of 1:40 and a dyestuff concentration as required for a 2/1 standard dyeing depth, and
- (b) a migrating ability such that it is capable of migrating to an extent of 25 to 40% in 60 minutes from a wool sample dyed in a 1/1 standard dyeing depth to an initially undyed wool sample of equal weight in a bath having a temperature of 98.+-.1.degree. C., a pH of 4.5 and a goods:liquor ratio of 1:40, said 25 to 40% being the ratio after said 60 minutes, of the amount of dyestuff on the initially undyed sample to the amount of dyestuff remaining on the dyed sample, and a leveling agent which is an alkoxylation product of an amine substituted by a C.sub.12-30 alkyl or alkenyl group or by a C.sub.13-31 alkylcarbonyl or alkenylcarbonyl group, provided that when the substrate is a wool/synthetic polyamide fiber blend the aqueous dyebath contains a mixture of monosulfonated acid dyestuffs.
Dependencies are inferred from the claim text.