Abstract
The dyeability and color tone of tussah silk fabric treated with chitosan were investigated using vat dye. An increase in dyeability was observed in chitosan-treated fabric than in untreated one. Dyeability of the fabric increased with the rate/amount of chitosan treatment in the following order: C. I. Solubilised Vat Blue 5 (acid method)<C. I. Vat Red 41<C. I. Vat Blue 1<C. I. Vat Blue 6. (or, A direct relationship was noted between dyeability and rate/amount of chitosan treatment. Increase in dyeability was noted in the following order: C. I. Solubilised Vat Blue 5 (acid method)<C. I. Vat Red 41<C. I. Vat Blue 1<C. I. Vat Blue 6.) On the other hand, dyeability of chitosan-treated fabric to C. I. Solubilised Vat Blue 5 using alkali method did not improve or even decreased as compared with the untreated fabric. In addition, treatment of fabric with chitosan resulted to large color differences in C. I. Vat Blue 1, C. I. Vat Red 41 and C. I. Vat Blue 6 dyes. It affected three color attributes in such a way that decreased brightness, increased saturation and small change in hue were observed. Moreover, the acid method using C. I. Solubilised Vat Blue 5 decreased the brightness and saturation but did not change the hue, thus, small color difference was noted.
