Dyeing methods
AssigneeL. B. Holliday & Co. Limited
InventorsAlexander Elliot, John Gerald Lee, Brian Lever
Life of this patent
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Abstract
The invention is concerned with a change in the current practice of dyeing natural and synthetic polyamide materials with reactive dyestuffs. The invention involves pre-treating the material to be dyed with an amphoteric auxiliary in a bath which is brought rapidly to the later dyeing temperature and which contains an amphoteric auxiliary preferably at a pH buffered within a specific range. It is found that the pre-treated material takes on the reactive dyestuff very readily and that the dyed materials have a good fastness. A major achievement is that the dyeing time is cut to about one-half of that presently employed.
Claims8
A method of dyeing machine washable wool fibers, the fibers having been chlorinated and resin-treated to provide machine washability, the method comprising:
- i. pre-treating the fibers in an aqueous bath containing a levelling agent for the dye, the pre-treatment being carried out at the dyeing temperature for a period of time in the range of from about 10 to 30 minutes, the dyeing temperature being in the range of from 70.degree. C to the boiling point;
- ii. adding to the bath a solution of a dyestuff material comprising at least one reactive dye, to form a dye bath;
- and
- iii. dyeing the pre-treated fibers in the dye bath at the dyeing temperature.
Dependencies are inferred from the claim text.