Kinetics of thermo-fixation of solvent dyes and pigments in polyester fibres

摘要

The diffusion coefficient of a dye in fibres is critical to understanding the dyeing process and coloration quality of products. In this paper, the diffusion kinetics of solvent dyes in the thermosol dyeing of polyester fibres was studied by measuring K/S of the dyed polyester fabrics based on the Kubelka-Munk equation. The diffusion coefficients of two model solvent dyes were estimated with Hill's equation using the experimentally measured K/S values and were found to be in good agreement with those calculated from the traditional extraction method. Such a measurement method was applied to several other solvent dyes and pigments that have different molecular sizes and a good correlation between the measured diffusion coefficients and sizes of these dyes and pigments was found. The results indicate that it is feasible to use K/S measurement of dyed fabrics and Hill's equation to evaluate the kinetics of the thermosol dyeing process under certain conditions.