Dyeing of PET fabric with CI Disperse Blue 79 using supercritical carbon dioxide as the medium

PET fabric was dyed with C. I. Disperse Blue 79 in supercritical carbon dioxide (SCD). The effect of variables, such as temperature, pressure, dyeing time etc, to the dye uptake ( measured as K/S) of PET fabrics was discussed. It was found that. when the dyeing temperature was raised, the dye uptake increased gradually, and approached to the equilibrium after 60 min at 120 similar to 130degreesC. The fastness of the dyed PET fabrics was about the same with the counterparts in water medium. From a kinetic of the dyeing in SCD, the diffusion coefficient and the activation energy of the dye in PET fabric in SCD were determined.