The application of chitosan in pigment printing

The use of chitosan as a combined thickener and binder in pigment printing has been examined in comparison with a commercial printing system (Alcoprin t). Printing pastes made up from mixtures of chitosan, pigment and acetic a cid at the appropriate viscosity gave satisfactory prints on polyester and 67:33 polyester/cotton woven fabrics. Rheological data showed the chitosan pigment paste had a much lower yield point than commercial printing paste t hough no difficulties were found in its use. Curing of the chitosan print a t 150 degrees C for 6 min gave samples of comparable colour fastness to the commercial printed samples when subjected to the rubbing and washing tests . The only drawbacks noted in using chitosan in this way were a reduced col our yield and a much higher fabric stiffness.