Process for dyeing wool
AssigneeHoechst Aktiengesellschaft
InventorsHans-Ulrich von der Eltz, Karl-Heinz Rostermundt, Klaus Turschmann
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Abstract
Trichromatic dyeings with acid dyes which exhaust from strongly acidic liquors have weaknesses with respect to wet fastness, which are due to insufficiently fast components (blue, red). It has been found, according to the invention, that by replacing the insufficiently fast acid dyes by reactive dyes of the vinylsulfonyl type and retaining the method of dyeing under strongly acidic conditions the wet fastness level of the exhaust dyeings can be improved while the levelness obtained remains as good.
Claims9
A process for the level dyeing of wool or of the wool portion of a fiber blend by the exhaust dyeing technique, with a trichromatic dyeing recipe, said process comprising:
- bringing the wool or fiber blend into contact containing an aqueous exhaust liquor containing the trichromatic dyeing recipe and dyeing the wool or fiber blend while maintaining a dyeing pH between 2 and 3 and a temperature in the range of 95.degree. to 110.degree. C., said trichromatic dyeing recipe consisting essentially of at least three dyestuffs, at least one, but not all, of the dyestuffs being an acid dye which exhausts under strongly acid conditions, and at least one, but not all, of the dyestuffs being a reactive dye contaiing in the molecule at least one group which, under fixing conditions, reacts with the fiber via the vinyl sulfonyl radical by nucleophilic addition;
- cooling the resulting dyed wool or fiber blend, and
- recovering dyed wool or fiber blend exhibiting level trichromatic effects.
Dependencies are inferred from the claim text.