Improved dyeing method of hydrophobic fiber with dye substance in supercritical fluid carbon dioxide

摘要

Processes for dyeing a hydrophobic textile fiber with a colorant material using a SCF-CO2 dyebath are described. One process employs cooling, without venting or removing CO2 from the system, to a target CO2 temperature at or below the glass transition temperature of the hydrophobic fiber, followed by the venting of the dyeing system to atmospheric pressure. The other process employs venting, without cooling, to a target CO2 density where dye is no longer soluble in the SCF-CO2, followed by cooling to a target temperature and then venting to atmospheric pressure. Optionally, the temperature of the dyeing process is established by heating the process according to a selected temperature profile.