Influence of Dye Size and Fiber Porosity on the Dyeing Kinetics and Time Lags in the Uptake of Cationic Dyes on Acrylic Fibers

Abstract

The uptake curves of cationic thiazine dyes (based on thionine) and four other cationic dyes were determined for a series of acrylic fibers, consisting of the same polymer but varying porosities. The apparent diffusion coefficients ( D_app) and the time lag of the dye uptake (Δ t) were calculated. D_app and Δ t are functions of the size of the dye cations, the porosity of the fiber, and at least one other factor. We detected an influence of the glass transition temperature under dyeing conditions on the time lag, which was not found before for these or any other fibers.