Abstract: The dye solubility in supercritical CO₂ directly influences the dye-uptake and the performance of the dyed fabric. The measuring of the dye solubility in supercritical CO₂ is particularly important. The paper used the dynamic method to measure the solubility of disperse orange 30 and Disperse blue HGL in supercritical CO₂ respectively in different temperature and pressure ranges, and analyzed the effects of temperature and pressure on the solubility of dyes in supercritical fluid dyeing. The experimental results indicated that the solubility of dyes increased with the increase of temperature. However, when the temperature rose to a certain extent, the solubility of dyes began to decrease. And the solubility of dyes increased with the increase of pressure, the increasing trend was obvious in the low-pressure region, while it became gentle gradually in the high-pressure region.

Key words: supercritical CO₂; disperse orange 30; disperse blue HGL; solubility