The effect of air and vapor permeability of material on heat and mass transfer in clothing systems has been investigated with experimental and theoretical model. When size of air space is set very small e. g. about 5mm, water vapor condensation occurs. In such a case, water vapor permeability has more effect on heat and mass transfer than air permeability. In comparison with vapor impermeable fabric, vapor permeable fabric decreases the amount of condensation heat flux. In other word, such a fabric can keep lows the temperature and the amount of absolute water vapor concentration in microclimate, high values of which cause humid and heat stress sensation to wearer. The numerical analysis shows that the velocity of convective flow in microclimate is highly related to air permeability of fabric. However, the convective flow rate in microclimate under an air impermeable clothing is faster than that of a permeable clothing, especially inlet at the lower edge. Additionally, for a garment without air and vapor permeability, only the pathway through the openings is available. This shows that thermal insulation and water vapor resistance of clothing-system are determined not only by fabric properties but also by constructive factors as how to wear, such as condition of upper and lower opening, size of air space of microclimate.

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In this paper, the active tactual motion while judging the hand of material of fabric was investigated. The speed of finger movement, the applied force, and the dynamical friction force in judging the hand of material of fabric, that is wool, cotton, and silk fabric, were measured with the experimental system composed of a CCD camera, an image processing unit, and a strain gauge. The results are as follows: (1) The judgement of the hand of material was influenced by the movement direction of the finger, and by the contact area between the finger and the fabric surface. (2) When the subject judged the hand of material of fabric after learning it, the speed of finger movement and the dynamic friction force became stable and the correct answer rate of material judgement increased. (3) The adjective “smooth”, which is one of the adjectives related with “hand of material”, was correlated with the coefficient of dynamical friction.

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Coloration phenomenon of L-tryptophan (Trp) derivative treated with dichloroacetic acid (DCA) was observed under varying pH, i.e., between purple (below pH 2.5) and yellow (above pH 4.0). To elucidate the coloration mechanism of Trp treated with DCA, the colored compound was fractionated and investigated spectroscopically. Trp formed yellow compound consist of tricyclic structure by treatment with DCA. The color change with the variation of pH is due to the dissociation of nitrogen atom in the tricycle. Colored copolypeptide hydrogel was also prepared by immersion of copoly (N-hydroxyethyl L-glutamine-co-Trp) membrane, which was obtained by aminolysis of copoly(γ-benzyl L-glutamate-co-Trp) in the presence of crosslinking agent, in DCA. Color change was also observed for the hydrogel. The pH dependence of the degree of swelling (Q_w) was investigated. The Q_w changed in the pH region of color change and reflected the results of Trp treated with DCA.

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Both the distribution of rosin and the water-penetrated portion in handsheet from hardwood BKP (L•BKP) with added some rosin were demonstrated by mapping using Electron Microprobe Analysis (EPMA). Rosin was chemically modified with O_sO₄ in gas phase, and water penetrated portion was labelled by making the sheet to absorb the 15% nickel sulfate solution. The distribution of rosin and the water-penetrated portion were observed from surface side and from cross section side, by observing O_sMα image and NiKα image. As rosin content increased, rosin were found to be distributed with higher concentration on paper surface layer and inside the paper. No NiKα images were found in the emitting portion of O_sMα and no O_sMα images were also found in the NiKα emitting portion.
This shows that the water can not penetrate into the rosin distributed sites. It became clear that the way of penetrating water was different between soap type rosin and emulsion type rosin in paper sheet before heat treatment. It was concluded furthermore that rosin concentration was increased and the water-penetrable portion was decreased by heat treatment of the sheets.

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From the point of felting shrinkage behavior of the raw and the chemically modified plain-knitted wool fabrics, the relationship between the density and the area of each shrunk sample after washing test was investigated. The relation for the raw sample shrunk by different levels of washing action resulted in U-shape curve. The result indicated that there were two significant shrinkage stages in the raw plain-knitted fabric. On the first stage that the fabric density decreased, the felting was caused entirely by fibers protruding from the surface. The main knit structure was quite unfelted, but the loops became largely narrow through being pulled in by the felting surface. On the second stage, which the density increased through the minimum density, the loops were completely deformed and the main structure was almost felted. The relation between the density of each shrunk chemically modified sample and the fabric area showed that the curve drawn by jointing together every top of those bar charts was similar in shape to that for the raw sample. This means that the felting shrinkage of shrinkproofing treated fabrics was subjected to the mechanisms of felting in the raw fabric.

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