The fatigue behaviors of polyester fibers of which the yarn-manufacturing conditions were different, in a rubber matrix were investigated in regard to the microstructures and the adhesive properties, by the model estimation method (disc and tube fatigue test). The fatigue properties were scarcely affected by the different yarn-manufacturing conditions and carboxyl end groups, but the important factors of the fatigue properties included to adhesion durability (heat resisitant adhesive properties and dynamic adhesive properties) of polyester fibers to the rubber matrix. According to the author's assumption, while the adhesive properties were kept high, the repeated stresses and strains were distributed over all the fibers. When the interfacial adhesive properties were degraded with the proceeding of the fatigue, the stresses were unevenly applied to the interfaces of the polyester fibers/the rubber.

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A composite foam was prepared by filling small cylindrical rigid foams in square lattice pattern in an ordinary flexible foam. All composite foam samples showed large compressive deformations at low hydraulic pressures. The deformation rate decreased as the hydraulic pressure increased and the deformation approached to a certain value. Compressive deformation of composite foam decreased with increase in volume fraction of cylindrical rigid foam. Compressive deformation estimated by finite element method agreed approximately with experimental value obtained by the apparatus built for this experiments. Overall coefficient of heat transmission estimated from average compressive strain by a finite element method roughly agreed with the heat transmission coefficient estimated from experimental average strain.

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Composite membranes from gelatin (GEL) and poly (ethylene terephthalate) (PET) were prepared by dissolving GEL and PET in hexafluoro-2-propanol, casting the obtained solution on a glass plate and evaporating the solvent in the presence or absence of an applied electric field. The microscopic observation, membrane potential measurement and thermal analysis showed that the membrane prepared under an electric field had a special morphology composed of cylindrical protein domains extended to the surfaces of the membrane, while the membrane prepared without an electric field had a random sea/island structure. The solute permeability of the membranes prepared under an electric field was much lager than that of the membranes prepared without an electric field. The pH-sensitivity of the solute permeation through each type of the membranes was also investigated. The results of permeability measurements supported the orientation of GEL in the composite membranes.

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An active transport system with a synthetic membrane has been proposed. The system that effectuates the transport is composed of (1) host molecules of which association constants with a specific substrate can be reversibly changed by photo-irradiation, a change in pH or temperature control, and (2) switching valves on both surfaces of the membrane. This study shows that an active transport can be achieved from successive passive transport steps and the energy for the transport is simply consumed as those for a change in the association constant of the host molecule, for opening and closing of switching valves and for the control of switching valves (i.e., vectorial control). Active transport, which has been considered to be a complicated biological system, is mimicked by a simple hybrid synthetic membrane system (i.e., hybrid-transport theory).

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Mechanical and optical properties of handsheets prepared from mixture of bleached kraft pulp and either microcrystalline cellulose powder (MCP), freeze-dried amorphous cellulose (FAC), or hydrated amorphous cellulose gel (HAC) were studied in terms of crystallinity of the additives and interaction between pulp fibers and the cellulose additives. X-ray diffraction patterns and moisture content of the handsheets showed that both FAC and HAC behaved as amorphous cellulose in handsheets. However, mechanical and optical properties such as Young's modulus, tensile index, tearing resistance, opacity, and scattering coefficients of handsheets showed that MCP and FAC behaved like fillers, and that HAC behaved like strength resins for improving interfiber bonding of pulp fibers. The handsheets had the maximum tensile strength and Young's modulus around 12% HAC content. Effects of the addition of HAC to pulp suspension on physical properties of handsheets seemed to be similar to those of beating of chemical pulp on physical properties of paper. These results and scanning electron micrographs of handsheets indicated that hydrated amorphous cellulose gel can form strong interfiber-bonding with pulp fibers, whereas little interaction is present between pulp fibers and MCP or FAC.

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A Dew sensor array method was developed to measure in-plane capillary water flow in various types of woven fabrics. Specimens used were woven fabrics made of various fiber materials and cotton and polyester filament fabrics whose weave densities were altered systematically. The water absorption constant K_H (cm/√s) was obtained by plotting distance traveled against square root of time elapsed, and water absorptivity was estimated from K_H. Based on Washburn's law, the in-plane capillary water flow in fabrics was considered to be governed by the pores with sizes about 1μm present at the fiber-fiber contact points between fibers. The K_H value decreased with increasing yarn density for the fabrics made of the same fibers and yarns. The in-plane anisotropy of water migration was suggested that the yarn was the unit for driving water migration in the case of woven fabrics.

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The purpose of this study is to find out whether any difference among the rating criteria of observers is present or not, and if present, what criteria cause the difference in the rating of becoming to clothes. The measurements were carried out for the subjects made up of three factors, wearers, clothes and hair-styles. The number of observers having differences in the rating was much more than that of the observers who gave the same rating. Observers were classified into three groups and each group was composed of observers who gave the same rating to the same subject. Two of the factors were common and one was different among the groups. Even for the common factors pertaining to clothes and hairstyles, the criteria of rating were different among the groups. The criteria of rating were expressed with the words which were classified into three types: (1) common to the groups (2) peculiar to a group, and (3) no rating.

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