Silk screen printing of some reactive dyes on gamma irradiated wool fabrics

Abstract

The sodium sulfonate side chain of the reactive dye Remazol Brilliant Red (masked form) was converted into the vinyl sulfone derivative (free form). Wool fabric, gamma irradiated at different doses, was printed by a paste containing the different forms of the reactive dye using the silk screen method. The effect of different factors that may affect the color strength of the printed wool fabric such as radiation dose, pH, additives and steaming time was investigated. In general, regardless of the studied factor, the fabric printed with the free form dye showed a remarkable color strength compared to that printed with the masked form. However, irradiation of wool fabric prior to printing increased the color strength to a noticeable extent. The pH of the printing paste at which the highest color strength was obtained was 5. When benzyl alcohol was added during the preparation of the printing paste, a significant enhancement in the color strength was observed. The optimum concentrations of benzyl alcohol for the free and masked forms are 30 and 45ml kg −1 (based on the weight of the thickener), respectively. Using other organic solvents such as perchloroethylene or tertiary butyl alcohol in the printing paste has the opposite effect on the color strength of the printed fabric.