Preparation of Ultrafine Pigment Dispersion and Investigation of its Adsorption Performance on Cationized Flax Substrate

An ultrafine pigment dispersion was prepared using sodium methylene dinaphthalene disulphonate (NNO) as the dispersant in conjunction with micro-jet milling. The particle size distribution measured by dynamic light scattering (DLS) showed that the pigment particle size was less than 200 nm, with the particles uniformly dispersed in aqueous media. Freeze thaw treatment indicated that the ultrafine pigment dispersion had good storage stability. Flax fabrics were cationized by means of a polymeric quaternary ammonium salt employing an exhaustive method and the adsorption properties of the ultrafine pigment on this substrate were investigated. The results indicated that the percentage adsorption performance of the pigment was influenced by the particle size, the pH, the time and the temperature. The kinetics of pigment adsorption were studied with the resulting data being fitted by the first-order rate equation. This allowed the respective first-order adsorption rate constant. k(1), and the adsorption half-time, t(1/2), to be calculated.