The moisture sorption isotherm was determined primarily at 30°C for fifteen kinds of wool and hair fibers from sheep, goat, camel, and rabbit families. The isotherm was analyzed in terms of Brunauer, Emmett and Teller (B. E. T.)'s parameters: C (adsorptive energy factor), v_m (maximum volume of adsorbed water in monolayer per gram of dry material), and n_max (maximum number of layers in multilayer adsorption), in order to discuss the moisture sorption properties in relation to structural feature of the materials.
Despite of wide variety of the wool and hair fibers, the values of the parameters were found to be almost equal to each other; i.e., C ranging from 9.40 to 11.7, v_m from 0.0574 to 0.0718 and n_max from 5 to 6. The X-ray crystallinity, X_x, was estimated by Ruland method as ranging from 24.2 to 30.9% in association with the value of lattice imperfection of around 5. The plots of v_m against the degree of noncrystallinity, (1-X_x), exhibited roughly a linear relation passing through origin with a slope of 0.0927 for a series of wool specimens, but deviated from the linear relation toward larger v_m side for particular specimens having the medulla structure.
The moisture sorption process was also investigated by thermodynamic means as a function of moisture regain of the specimen from dryness up to saturation. Namely, the differential heat of moisture sorption, Q_L (enthalpy difference of the sorbed water in reference to liquid water), and the excess energy, TΔS (entropy difference of the sorbed water also in reference to liquid water), were determined to conclude that the sorbed water is in highly ordered state at dryness and is still in a little more ordered state than in liquid state at saturation.

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A solution of a mixture of polyvinyl alcohol (PVA) and polyethylene glycol (PEG) in water gave a PVA hydrogel including PEG by a given cycle of freezing and thawing. The rate of the release of PEG from the gel decreased with increasing the molecular weight of PEG and the freezing cycle number. Diffusion coefficients of PEG in the gel were determined by the relationship between the release amounts and square root of release time. Diffusion coefficient decreased with increasing the cycle number, then becoming horizontal after a definite number of cycle which depended on the molecular weight of PEG. We found that emulsified triolein was also included in the gel by the freezing and thawing method.

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This work deals with the preparation of orthocortical and paracortical cells by a new method and the protein-chemical characterization of keratin proteins extracted from them. The preparation method consists of three procedures, i.e., i) removal of the cuticle from wool fibers by shaking with glass fiber snippets in aqueous propanol, ii) disintegration of decuticled wool fibers by successive freezing in formic acid, and iii) separation of the disintegrated cortical cells into ortho- and paracortical cells by using a difference in density between the two cortical cells. The relative amounts of the low-sulfur (Low-S), high-sulfer (High-S) and high-glycine-tyrosine (High-GT) protein components were estimated from the gel filtration chromatograms in 8M urea solution. For this analysis, S-car boxy methylkerateines (SCMK) were prepared from the cortical cells isolated. It was confirmed that the paracortex is rich in High-S proteins, while the orthocortex in Low-S proteins.

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To study the interfacial electrical properties of the nylon 6 fibers grafted with acrylic and methacrylic acid and the surface dyeability of cationic dye on these fibers, the ζ-Potential of the fibers was measured in the aqueous solution of Methylene Blue. With an increase in the concentration of the dye, the sign of the ζ-potential changed from negative to positive and the amount of the dye adsorbed on the fiber surface increased. These results suggest that electrostatic interaction and van der Waals force act between the fibers and the dye. The amount of the adsorbed dye decreased with an increase in the degree of grafing.
The free energy of adsorption (Δ_??_) of Methylene Blue on the fibers was calculated from the slope of the ζ-log C_d (C_d: the concentration of dye) curve etc. The negative value of Δ_??_ decreased with an increase in the degree of grafting. The heat of adsorption (Δ_??_) was negative and the entropy of adsorption (Δ_??_) was positive. The positive value of Δ_??_ suggests the importance of entropic interaction (the formation of hydrophobic bond) as a driving force to the adsorption of the dye on the fiber surface. The negative values of Δ_??_ of the ungrafted and the grafted nylon 6 fibers were larger than those of the ungrafted and the grafted polyester fibers, and the Δ_??_ values of the former were smaller than those of the latter documented in our recent report. Therefore, the dependence of hydrophobic bond on the ungrafted and the grafted nylon 6 fibers was smaller than that on the ungrafted and the grafted polyester fibers. It is concluded that the surface dyeability of Methylene Blue on the grafted nylon 6 fibers is lower than that on the ungrafted nylon 6 fiber, because the water-soluble polymer layer is formed at the fiber surface due to the grafted polymer chains.

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The simultaneous effect of light and perspiration on the fading of 6 vinylsulfonyl reactive dyes, C. I. Reactive Red 22, Blue 19, Black 5, an aminopyrazolinyl azo dye (Yellow), a copper complex azo dye (Blue-Cu) and a copper phthalocyanine dye (Cu-Pc), on cellulose fabrics was investigated by the use of the ‘A method’ of JIS L 0888 with the artificial acidic perspiration of the ATTS (Association for Textile Technical Study) and JIS L 0848. By removing each component from the ATTS artificial perspiration, these dyes were classified into two groups depending on the fading behavior by the component, of which, with an exception, lactic acid gave the largest effect followed by histidine and glucose in decreasing order. Aspartic and panthotenic acids gave a suppression effect with an exception. The ATTS artificial perspiration and lactic acid gave the severe fading for C. I. Reactive Black 5, while the artificial acidic perspiration of JIS L 0848 gave a weak one. The dyed fabrics after soaking in aqueous solutions containing each one component of lactic acid, histidine, glucose, panthotenic acid and aspartic acid showed so complex fading behavior that the simple comparison among the effect of each component could not be made. The effect of component on the fading of VS dyes were appeared in the initial fading in which excess amount of aqueous solution on fabrics took a part and in the subsequent fading under the conditions of 100% RH after the evaporation of excess water. Water gave the accerelated fading in the decreasing order: Red 22>Yellow>Black 5>Blue-Cu>Cu-Pc>Blue 19. Panthotenic acid gave an accerelated effect on the fading when used singly, but a supression effect in a mixture of lactic acid. Cu-Pc was photoreduced during the exposure after soaking in the artificial perspiration, which was shown by the color of leuco compound formed on fabrics and recolored after the oxidation in water or in air.

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