Indigo dyeing process and apparatus and indigo dyed yarns and fabrics made thereby
AssigneeIndigo Mill Designs, Inc.
InventorsHoward Malpass, Ralph Tharpe, M. Dean Ethridge
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Abstract
Processes are disclosed which substantially eliminate the formation of oxidized indigo dye before and during dye application onto a natural fiber yarn or fabric while allowing the leuco-indigo dye molecule to diffuse fully into the natural fibers of the yarn where it can fix to the fibers prior to oxidation (i.e., exposure of the leuco-dyed yarns to oxygen). Indigo dyed textile products (e.g., dyed cotton yarns that may be twill woven to form a denim fabric) exhibit exceptionally high colorfastness as determined by the AATCC Crock Test.
Claims21
A process for indigo dyeing of textile products comprising the steps of:
- (a) introducing an undyed textile product into a dye application chamber having an anaerobic atmosphere;
- (b) establishing fluid communication between the anaerobic atmosphere and an oxygen purification system to maintain anaerobic conditions within the dye application chamber;
- (c) applying a leuco-indigo dye solution onto the undyed textile product introduced into the dye application chamber according to step (a) within the anaerobic atmosphere thereof to form a leuco-indigo dyed textile product;
- and thereafter
- (d) exposing the leuco-indigo dyed textile product to an oxygen-containing atmosphere to oxidize the leuco-indigo dye applied to the textile product and thereby form an indigo-dyed textile product.
Dependencies are inferred from the claim text.