Kinetics of dyeing of polyester with CI Disperse Blue 79 in supercritical carbon dioxide

Polyester fabric was dyed with CI Disperse Blue 79 in supercritical carbon dioxide and the effect of temperature and dyeing time on dye uptake was studied. On raising the temperature at constant pressure the dye uptake gradually increased, reaching equilibrium after 60 min. The diffusion coefficient at different temperatures and the activation energy of the dye on polyester fabric in supercritical carbon dioxide have been determined. The latter was found to be considerably lower than the corresponding figure for conventional dyeing.