Utilizing Alkali-Treated Starches As Thickeners In Vat Print Paste Dyes

摘要

The suitability of alkali-treated starches as thickening agents, either alone or in admixture with sodium algi-nate, in printing cotton fabrics with vat dyes was thoroughly investigated. It was found that cotton fabrics printed using alkali-treated starches acquire a soft handle, high K/S and better overall fastness properties than their corresponding samples printed using cooked starches. Maize starch is more suitable as a thickening agent in textile printing than rice starch, and it can be used either alone or in admixture with sodium alginate. The results indicate that the K/S depends on the nature of reducing agent used and follows the following order: thiourea dioxide > Rongalite~® FD > Rongalite~® C. The nature of alkali incorporated in the printing pastes has a remarkable effect on the properties of the printed goods. From both a scientific and economic point of view, alkali-treated maize starch before precipita-tion is preferred as a thickening agent than after precipitation.