STUDIES ON DYEING PROPERTIES OF DISPERSE DYES

(1) THE EXPERIMENTAL INVESTIGATION ON THE METHOD OF CYLINDRICAL POLYESTER FILM ROLL

Abstract

The application of the method of cylindrical polyester film (Mylar) roll to the studies on the dyeing properties of polyester fiber were investigated, with special concern on the relationship between the surface dye concentration and equilibrium adsorption, and between the dye concentration and diffusion coefficient.
The results are as follow:
1) The roll film method used for dyeing cellulose with direct dye can be used for polyester.
2) The surface dye-concentrations calculated from the roll film method are about the same as that adsorbed on fiber nnder equilirium, Hence this method has the virtue of obtaining diffusion coefficient and partition coefficient at the same time.
3) Relations between the apparent diffusion coefficients and the dye concentrations are independent in all cases except 4-Nitro-4'-Hydroxylazobenzene which can be expressed as:
Ci: Dye-concentration.
D: Apparent diffusion coefficient at Ci.
D₀: Apparent diffucient at zero dye-concentration.
m: The slope of the D vs. Ci curve.