Diffusion of disperse dyes into microfibres and conventional polyester fibres

The dyeing properties of polyester microfibres are quite different from those of conventional polyester fibres In this paper, the sorption isotherms, the diffusion coefficients and the amount and rate of dye uptake Into the fibres are compared for both conventional fibres and microfibres. Shibusawa's approximation of Hill's equation is used to compute the diffusion coefficient, which depends on the initial dye concentration, the time and the fibre count for a fixed temperature (130 degreesC) The kinetic properties are analysed only under infinite bath conditions. The sorption Isotherms and diffusion coefficients as functions of time for conventional polyester fibres and microfibres are compared by considering the surface area and the diffusional boundary layer influence.