Wolfgang Saus

DYEING OF TEXTILES IN SUPERCRITICAL CARBON DIOXIDE

A new dyeing process is reported for synthetic fibers and fabrics. The use of super critical fluids, especially supercritical carbon dioxide, as dyeing media completely avoids water pollution. Laboratory results are reported on the dyeing of poly(ethylene tere phthalate) and other synthetic materials and on factors influencing dye uptake and levelness. The fundamentals and future aspects of this new procedure are discussed.

DYEING NATURAL FIBERS WITH DISPERSE DYES IN SUPERCRITICAL CARBON DIOXIDE

Because of the success of dyeing synthetic fibers with disperse dyes in supercritical carbon dioxide, we have investigated the possibility of dyeing natural fibers with this technique. Experiments are presented for wool and cotton dyeings after a special pretreatment.

Voltammetric determination of reducing agents and dyestuffs in textile printing pastes

SummaryBasic research concerning voltammetry in highly viscous, paste-like systems is presented. Using model compounds for dyestuffs and reducing agents, respectively, the principal applicability of electrochemical techniques for direct quantitative determination of electroactive compounds in such media is proved. The influence of non-Newtonian viscosic properties of the thickeners used (polygalactomannanes, carboxymethylcellulose) on current voltage curves obtained with rotating electrodes is discussed. An increase of the anodic measuring range due to electrode surface modification by the products of the electrode reaction of hydroxymethanesulphinate and by the properties of the thickeners is evaluated.