A new preparative method for cross-sectioning and staining of fibrous materials was developed and the differential staining was applied to reconfirm the bilateral structure of Merino wool fibers under an optical microscope observation. A part of a cross-section (ortho-cortex) of a Merino wool fiber was stained specifically by some selected basic dyes independent of pH of the medium while only at pH 6.86 by Acid Violet. The other part of the cross-section (para-cortex) was stained by Ponceau 2R at pH 6.86 at 60°C for 1h. The mechanism of differential staining of wool fibers having bilateral structure by basic dyes and acid dyes was investigated in detail.

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Water-reswelling capability of pulp fibers was studied by water retention value applied to paper sheet. (WRV-PS) Optimum conditions for determining WRV-PS were first examined, and the WRV-PS obtained by centrifugation at 3000 G for 15min can be regarded as a peculiar value for characterizing reswelling properties of paper sheets. Effects of beating, couching, pressing and drying in handsheet-making on reswelling capability of paper sheet were sensitively and clearly detected by the WRV-PS, in comparison with equilibrium moisture content or specific surface area. A decrease in WRVs-PS by pressing and/or drying reflected the formation of hydrogen bonds of pulp fibers in paper sheet. Furthermore, the decrease in WRVs-PS or the formation of hydrogen bonds in pulp fibers occurred in pressing or dried paper web at water content below the fiber saturation point. Therefore, WRV-PS is widely applicable to evaluation of reswelling properties of paper sheet.

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It was revealed by experiments using a thermal manikin that the openings of a clothing affects the heat transfer from an exposed skin part of a human body as well as that from a skin portion covered with clothes. Contrary to the covered skin part, the heat transfer coefficient was larger when an opening was closed than when one was open, for both of the upper and lower openings. Because the effect of convection on the heat transfer of the exposed body was considered, isotherms were visualized on a hot-plate-skin-model by means of the Mach-Zehnder interferometry. When cold air outside flows into the boundary layer around the exposed skin, the temperature gradient becomes narrower compared with that without air inflow. The results verified that cold air outside flowed into the boundary layer around the exposed skin in the case where the openings were closed. Only the air near the exposed skin was heated locally, which caused a decrease in the air density; therefore cold air outside flowed into this layer. On the contrary, in case where the upper opening was open, warm air which was heated by the covered portion flows upwards and heated the cold air around the exposed part. These are the reasons for the fact that the heat transfer coefficient of the exposed skin without opening was larger than that with opening.

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The model of the large deflection of fabrics considering the effect of bending hysteresis was established for describing the post-buckling behavior of woven fabrics. The moment-curvature relationship of fabrics obtained by pure bending test was approximated by the Rate-model and the change in the flexural rigidity caused by the hysteresis was incorporated into the analysis. Using a nonlinear FEM, the post-buckling behavior was solved for a few fabrics as examples whose ends were fixed horizontally. The numerical results agreed well with the experimental ones which showed hysteretic behavior. The present method was verified to make it possible to estimate the post-buckling behavior of fabrics from their bending moment-curvature relations. The influence of the bending rigidity on the linear approximation was investigated. The effect of the initial deflection on the post-buckling behavior that was calculated with considering the nonlinearity in bending rigidity was also examined.

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A computer simulation technique, previously developed by the same authors for predicting the 3-dimensional form of garment, was extended to the estimation of the garment pressure distribution. Using this system, the distribution of pressure on garments was calculated. Using computer graphics, distribution of garment pressure was displayed in the variation of hue. The 3-dimensional distribution of the garment pressure was reversely mapped on the paper pattern in order to indicate the preferable modification.

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Transfer of dyes into micelles of nonionic surfactants from water was spectroscopically investigated. The used dyes were o- or p- hydroxy-2-styrylbenzo [a] quinolizium salts (azonia dyes) (I), such as A (OH), B (OH) and the methyl derivative of B (OH) such as C (OH) and their betain dyes (II), A (O^-), B (O^-), and C (O^-). The transfer equilibrium constants of these dyes and their absorption spectra were determined in case of the double component system by the Principal Component Analytical method (abbreviated by PCA or PCM). A new analytical method was developed for the case of double component system but absence of isosbestic point. The obtained results by this method were compared with that reported in the preceding paper, calculated using only the data of the case of the double component system and presence of the isosbestic point. The results show that the azonia dyes (I) can more easily transfer into the micell than the betain dyes (II), because the equilibrium constants of the dye (I) were larger than that of the dye (II). The spectra of the dye (II) shifted more bathochromically in the micell than that of the dye (I), according to the hydrophobicity of inner micell.

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Using the sectional stochastic fractal variable, a texture of nonwoven fabrics was easily characterized. A recent development of fractal theory makes it possible to construct a mathematical model for the texture of nonwoven fabrics by using the so-called fractal dimension. Reformulating the fractal dimension as the sectional stochastic fractal variable, the texture of the nonwoven fabric was described with the sectional stochastic fractal variable. With the aid of the well-known theory of maximum likelihood method, the algorithm for categorizing the nonwoven fabrics was proposed. This algorithm was numerically checked by using the actual data.

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A toluene solution of styrene/cellulose graft copolymer which had been prepared by using cellulose gel as an substrate was dispersed in an excess of water. Then the system was allowed to stand for hours at room temperature to be transformed into macroscopic two phases which consist of a transparent toluene phase and a clear water phase. The toluene of the former phase was evaporated with the intention of preparing the film containing toluene-water interface.
Static contact angles of the films against deionized water revealed that the surface of the water phase side of the film was covered with cellulose.

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