To clarify the physical properties of silk yarns, cocoons and yarns of 12 different silk species were analyzed by solid-state ¹³CNMR and their amino acid compositions and spin-lattice relaxation time (T₁) were compared. The correlation between these values and physical values of yarns obtained by tensile strength measurements were discussed. Mole fraction of glycine (glycine⁄(glycine+alanine+serine+valine)) and T₁ of cocoons and yarns were different depending on the silk species. These values of cocoons in Japanese species scattered over a wide range and showed high correlation between them. On the other hand those of the Chinese species are in a narrow range , and T₁’s are smaller than Japanese ones. Among them Shisensanmin, Kankokakuken and Ikoken showed extremely large mole fractions of glycine and small T₁, meaning that these three species have excellent rigid but soft physical property. Mole fraction of glycine and T₁’s of most of the Japanese species in yarns became larger than those of cocoons. Japanese species increased their flexibility by reeling, but Chinese and European species decreased it. Among them Matamukashi, Onichijira and Kankokakuken showed excellent rigid but soft physical property in yarns. Mole fraction of glycine showed high correlation with viscosity and T₁ showed high correlation with Young’s modulus. In these correlations there are differences between Japanese and Chinese species.

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D-lactic acid was synthesized from D-lactic acid methyl ester. Oligomeric (D-lactic acid) (ODLA) was prepared by dehydration condensation of D-lactic acid under high temperature and reduced pressure. Blend films of poly(L-lactic acid) (PLLA) and oligomeric (D-lactic acid) (ODLA) were obtained by cast method from their chloroform solutions. Properties of the blends were studied by polarizing microscopy, wide-angle X-ray diffraction (WAXD), differential scanning calorimetry (DSC), dynamic viscoelasticity measurement and tensile test. WAXD and DSC results showed that the stereocomplex crystal was formed in the blends and the melting temperature was higher than that of PLLA crystal. It was found from the results of DSC and dynamic viscoelasticity measurements that the formation of stereocomplex crystal disturbed the mobility of PLLA chain in the amorphous region of the blends. Furthermore, it was found that the mechanical properties of the PLLA film were hardly influenced by the addition of ODLA.

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The dyeing properties of Argon (Ar)-plasma treated wool were studied using the six classes of dyestuffs, i.e., acid, acid metal complex, acid mordant, reactive, basic and disperse dyes. Ar-plasma treatment greatly improved the color yield and levelness, together with the decrease of tippy dyeing. A condition in the plasma treatment enhanced not only the color yield but also the anti-felting performance, which is due to high hydrophilic effect. The relationship between the improvement of dyeing properties by the plasma treatment and the chemical structure of the dyes was also examined. In the case of the acid dyes, the effect of plasma treatment on color yield was more significant for the milling type dyes with large molecular weight than the leveling type dye with low molecular weight. For the acid metal complex dyes, the hydrophilic groups in the dye molecules did not influence the color yield. Although, in the case of the acid mordant dyes with small molecular weight, the similar effect on color yield to that of the leveling type acid dyes was expected, the effect was almost the same as that of the milling type acid dyes with high molecular weight. The SO_X groups should be generated on the surface of wool by plasma treatment, but any effects on color yield for the basic dyes could hardly be observed. Furthermore, the hot water and rubbing fastness were improved by Ar-plasma treatment.

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A prediction method of surface color of union fabric from individual color of yarns and weave was established. Thirteen color yarns were adopted as yarn samples, and sixty union fabrics consisted of two colors of yarns were weaved as fabric samples. Kubelka-Munk's law and Lambert-Beer's law were used to predict surface color as theory of subtractive color mixing. Moreover the isomeric matching method was used for making spectral reflection factor in prediction. It is an ideal color matching method that spectral reflection factor of object color is matched with spectral reflection factor of assignment color. The relationship among the density of predicted color(D_F(λ)), the density of warp and weft colors(D_warp(λ), D_weft(λ)) and the area ratio of warp and weft(S, 1-S) could be expressed as follows:
D_F(λ)=S·D_warp(λ)+(1-S)·D_weft(λ)
In order to reduce the difference between the predicted color and the measured color, the difference between density of warp and weft was considered. As a result, the surface color of union fabric can be predicted accurately.

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