Chinon fabric was treated with Pronase P, Papain C-400 or Proteoliquifase to introduce microvoid spaces in parallel with a significant elimination of the protein component. From the adsorption isotherms for the interaction between the enzyme-treated Chinon and some acid dyes at 90°C, the interaction was analyzed by using Scatchard plot. Under the acidic conditions (pH3.3 and 4.0), the maximum amount of dye-uptake (
DFmax) of C. I. Acid Orange 7 or Red 249 by Chinon fabric was mostly decreased by the respective enzymatic treatments in parallel with the decrease of protein content in the fiber, being independent of the kind of enzyme. However,
DFmax of Chinon at a nearly neutral pH was hardly affected by the enzymatic treatment. Furthermore, the affinity constant (
K) of Chinon fabric for the dyes were hardly affected by the respective enzymatic treatment. On the other hand,
DFmax of the synthetic fibers, nylon and Exlan, were unaffected by the pH value, while the dye-uptake by the natural proteinic fibers, silk and wool, apparently decreased with the increase of pH value similarly to the cases of the intact and enzyme-treated Chinon fabric.
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