抄録
To clarify the dyeability of shrink-proofed wool fabrics treated with permonosulfate (PMS) and a keratinase,
the sorption behaviors of four kinds of leveling acid dyes containing mono-, di-, and tri-sulfonate groups were
investigated. The dyeing rate and sorption isotherms were determined to elucidate the effects of the dye structure and the
treatment of wool fibers. The dyeing rate was discussed using apparent diffusion coefficients. The sorption isotherms
were analyzed using dual sorption mechanism to calculate the sorption parameters, the number of binding sites S , the
intrinsic binding constant KL, and the partition coefficient KP. As a result, the dyeing rate and the equilibrium dye uptake
for the fibers treated with PMS alone were much smaller than those of the untreated ones. The dyeing rate and the
equilibrium dye uptake were restored by the subsequent treatment with the enzyme. The S and KL values were also
decreased by the oxidation with PMS. On the other hand, the ESCA and FT-IR spectra showed the presence of cystine
monoxide (-SO-S-), cystine dioxide (-SO2-S-), and cysteic acid (-SO3
-) after the treatment with PMS. The observations
obtained for the dyeing behaviors can be explained in the presence of cysteic acid generated in the fibers after the PMS
treatment. It is likely that the decrease of dye uptake and S is due to the neutralization between the cysteic acid
introduced by the oxidation and the protonated amino groups in the fibers that work as the binding sites for the dye
anions. This tendency appeared strongly for the tri-sulfonate dye compared to the mono-sulfonate dye.
