Dry transfer printing of silk and cotton with reactive dyes and mixed polysaccharide thickeners

Dry transfer technology involving adhesion and steaming was designed for the printing of untreated silk and cotton with reactive dyes. The transfer paper was prepared by coating mixed polysaccharide thickeners composed of adhesive high-substituted hydroxypropyl cellulose (H-HPC) and another thickener, either sodium alginate (SA), carboxymethyl cellulose (CMC), hydroxyethyl cellulose (HEC), guar gum (SG-9) or carboxymethyl starch (SG-24). Patterns on the transfer paper were obtained by means of ink-jet. The thermal plasticity of H-HPC was observed and 120 degrees C was determined as the adhesion temperature. Rheological testing of all the thickeners verified that their shear-thinning behaviour favoured successful coating. By comparing the effects of different mixed thickeners on the prints' quality with regard to colour depth, sharpness, colour fastness and handle, it was concluded that the colour depth depended on the adhesion extent and reactivity between the thickener and reactive dye. Using H-HPC/SA and H-HPC/HEC produced the highest and lowest colour depths, respectively. The sharpness was visibly influenced by the different mixed thickeners. A clear pattern was achieved when the other thickener was CMC, SG-9 or SG-24. Both the colour fastness and handle were desirable, irrespective of the mixed thickeners used.