Abstract
The purpose of this work is to obtain the information on the dyeing behavior of polyester with disperse dyes from a perchloroethylene solution. The absorption isotherms for C. I. Disperse Red 88, azo-type, (I) and C. I. Disperse Red 60, anthraquinone-type, (II) were determined at 5°C intervals from 100° to 120°C, using polyester film. The absorption isotherms obtained were linear for all dyes. From the absorption isotherms, the partition coefficient and the heat of dyeing were calculated. The partition coefficient ranged from 8-14 for dye (I) to 0.6-0.7 for dye (II). These values are much smaller than for aqueous dyeing at the same temperature. The heats of dyeing for dye (I) and dye (II) were -7 and -2 kcal, respectively. These values are larger ca. 4 kcal than for aqueous dyeing. The diffusion coefficient in the substrate for dye (I) and dye (II) were determined at various temperatures by means of film roll method. The polyester film used was pretreated in a blank dyebath at 120°C. The diffusion coefficients thus obtained did not show any dependency on the concentration of the absorped dye in the film. The diffusion coefficient ranged from 2.56×10-9-2.74×10-8 for dye (I) to 1.87×10-8-5.91×10-8 cm2/min for dye (II). These diffusion coefficient are much larger than for aqueous dyeing. From the temperature dependence of diffusion coefficient, the activation energies for diffusion were calculated for dye (I) and dye (II). They were 32 and 17 kcal, respectively, which are smaller than for aqueous dyeing. From the results obtained in this work, a schematic drawing for swollen polyester in perchloroethylene was obtained.
