Patent ID: 6048369
Filing Date: 2000-04-11
Classification: D06B,D06P,Y10S

Abstract:
A process for dyeing a hydrophobic textile fiber with a colorant material in SCF--CO.sub.2, the process comprising the steps of:(a) selecting a colorant material according to a solubility path for the colorant material in SCF--CO.sub.2 wherein the selected colorant material is relatively more soluble in SCF--CO.sub.2 at a first temperature range and relatively less soluble in SCF--CO.sub.2 or near-critical fluid CO.sub.2 at a second temperature range, wherein the first temperature range is higher than the second temperature range;(b) heating the hydrophobic textile fiber and the colorant material in SCF--CO.sub.2 under SCF pressure conditions to a temperature within the first temperature range to initiate dyeing; and(c) dyeing the hydrophobic textile fiber by cooling the process to a temperature within the second temperature range without venting the SCF--CO.sub.2, whereby SCF--CO.sub.2 density remains constant.