Antimicrobial finish of textiles by chitosan UV-curing

In this work cotton, silk fabrics and synthetic filter fabrics were impregnated with an acid solution of chitosan and photoinitiator and cured at room temperature by exposure to UV light. Process conditions such as percentage weight on, dilution, irradiation time and power, chitosan-fabric contact time were optimized in order to improve treatment fastness. Obtained results showed a strong antimicrobial activity conferred by the treatment, homogeneous on fabric surface. It is evident already at low weights on, not affecting the hand properties of cotton or silk and the filtration characteristics of synthetic fabrics. Finally, fastness was better for silk and for samples prepared with the better interpenetration of chitosan inside fibers, nevertheless it was found that the lost in antimicrobial activity was not due to lost of chitosan from the fabrics but probably to the interaction between surfactant and chitosan.