Dyeing cellulose fibers with reactive disperse dyes in supercritical carbon dioxide

Dyeing of cellulose fibers with reactive disperse dyes is attempted using supercritical carbon dioxide (SC-CO2) as a solvent at 393 K and 20 MPa. For pretreatment, cellulose fibers are treated with tetraethylene glycol dimethylether or N-methyl-2-pyrrolidinone. Results are compared with dyeing with other disperse dyes under the same conditions. The color yield of the fibers is assessed by K/S measurements before and after washing to investigate dyeing quality in this medium. Good color intensity and wash fastness are obtained.