Waterless dyeing is the new approach in textile dyeing in order to reduce o
r eliminate effluent waste, and supercritical carbon dioxide is an alternat
ive solvent being considered. The research focus has therefore been on dete
rmination of dyestuff solubilities in supercritical carbon dioxide. We have
determined the solubilities of two disperse dyes (C. I. Disperse Yellow 7,
C. I. Disperse Oranges 11) and three mordant dyes (C. I. Mordant Brown, C.
I. Mordant Yellow 12, and C. I. Mordant Red 11) at 323-343 K and pressures
in the range 132-195 bar. Mordant Brown had the highest solubility in the
range (1.2-5.1) x 10(-4) mole fraction whereas Mordant Yellow 12 had the lo
west solubility in the range (1.7-5.1) x 10(-7) mole fraction. The disperse
dyes and Mordant Red had solubilities of the order 10(-6) mole fraction.