It was investigated how polyester fibers in a rubber matrix were fatigued and fractured by the model estimation method (disc and tube fatigue test). The results were discussed from the standpoints of fracture modes and morphologies. The fatigue rupture section under the disc fatigue, buckling phenomena, probably caused by the compressive shear stress. The breaking morphologies become more complicate with the increase of the compression ratio. In the case of the high adhesion strength between fiber and matrix rubber, a snap-back, round shape fiber ends were observed. On the other hand, for the poor adhesion, an acute knife-edge shape was observed. In the case of the tube fatigue, a “mushroom” shape probably by melt-rupture is presented. This suggests that the temperature of the fibers themselves becomes considerably high at the point of rupture. These morphologies are obviously different from those generated by simple tensile breaking and are characteristic for the fatigue.

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Poly (ethylene terephthalate) (PET) filament yarn was heat-treated at 100°C to 220°C for 10min under fixed state in air, and then treated with a 40% aqueous hydrazine monohydrate solution at 60°C for 3, 4, and 5h. Effect of the heat-setting pretreatment on the hydrazine treatment of PET fiber was investigated on the basis of weight loss, dyeing property, and morphological change. Weight loss by the hydrazine treatment decreased with the increase of heat-setting temperature up to around 160°C, and it increased again at temperatures higher than 160°C, as is the same behavior in dyeing of the heat-set PET fiber with disperse dyes. It is well known that the hydrazine treatment incorporates hydrazide groups in PET fiber and the fiber is dyed with acid dyes. Dye exhaustion curve with C. I. Acid Orange 7 showed a minimum at a heat-setting temperature of 160°C. Many cracks were produced perpendicular to the fiber axis by the hydrazine treatment and the effect was the smallest at a heat-setting temperature of 160°C. Crystallinity of the heat-set PET fiber was increased considerably by the hydrazine treatment. It is considered that the hydrazine treatment takes place mainly in the amorphous region of the PET fiber.

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Merino wool top was treated with low temperature plasmas of oxygen, tetrafluoromethane, and methane. Then the fibers were dyed with leveling and milling type acid dyes. Whereas the oxygen plasma treatment incorporated oxygen atoms on the fiber and led to hydrophilic surface, tetrafluoromethane plasma treatment took up a lot of fluorine atoms and produced hydrophobic surface. However, the rates of dyeing for both plasma treated fibers were much larger than that for a untreated fiber, regardless of the surface wettability. On the other hand, methane plasma treatment decreased dye exhaustion because hydrocarbon polymer was produced by the treatment and covered the fiber surface. Time of half-dyeing was reduced not only by oxygen plasma but also by tetrafluoromethane plasma treatments. Barrier effect in dyeing of the wool was diminished by both plasma treatments. Therefore, there is no relationship between wettability to water and rate of dyeing of the plasma-treated wool. It is considered that both plasma pretreatments relax the adhesive filler in interscale of the wool fiber and accelerate dye penetration into the fiber.

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Fibers and films of both p- and m-aramid fibers and films were treated with sputter-etching in the presence of argon. Surface of the treated films was investigated using scanning electron microscope (SEM) and electron spectroscopy for chemical analysis (ESCA). Many protrusions were produced on the surface of both films by the sputter-etching. In the case of p-aramid film, protrusions were grown in height with etching time. Then the top portions became large by coupling themselves after the long treatment for 20min. m-Aramid film also showed protrusions, but they were relatively smaller than those of p-aramid film. Contact angle to water of the sputter-etched films decreased rapidly at the initial treatment, while the critical surface tension increased drasticaly. ESCA analysis was carried out to elucidate the chemical changes on the film surfaces. The O_1S/C_1S ratio of the p-aramid film was increased obviously with the treatment of sputter-etching. This indicates the oxygen uptake in the etched surface, showing the simultaneous action of chemical modification induced by sputter-etching.

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Coating of chitosan on cellophane was studied with the aim of giving new functional properties to cellophane film. The transparency and the water vapor transmission rate of cellophane were not lowered by the chitosan coating on cellophane. The adhesive strength between cellophane and chitosan layers was very high, and increased with the chitosan concentration of the coating layer at the alkali-treatment stage. The adhesive strength of 170kgf/cm² was obtained when the chitosan concentration of the coating layer was 90%. Chitosan coating was not so effective in improving tensile and tearing strengths of cellophane. The chitosan layer readily absorbed silver ions, and the coating film bearing silver had antibacterial action against four pathogenic bacteria, namely Escherichia coli, Salmonella typhimurium, Vibrio parahaemolyticus, and Staphylococcus aureus. Silver of 1500ppm in the coating film was sufficient to prevent the propagation of the bacteria, while the coating film without silver did not have the discernible antibacterial action.

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Over 150 mummies had been found in one of the noble tombs (B. C. 15-16 C.) on the west bank of the Nile in Luxor, Egypt•UAR by Egyptian culture center of Waseda University. The tombs were the rock-cut graves built in the slope of the low terrace. Six linen specimens, which had been used for mummy-cloth or a bandage in this tomb, were analysed and compared to modern linen with no chemical treatment. 56-126mmol/glucose unit of aldehyde groups and 31-102mmol/glucose unit of ketone groups were formed in the ancient linen by oxidation over the long period of time, while carboxyl groups were hardly detected. The linens exhibited low D. P., although neither the cellulose crystallinities nor the crystallite sizes in the lateral dimension, estimated with the (020) reflection, were significantly different from each value of the modern linen. These facts suggest that the slow oxidation proceeded in such dry and dark environment as the tomb, and that the reaction especially in the crystalline regions were accompanied with the cleavage of the molecular chains rather than that of the inter-molecular hydrogen bonds by hydroxyl groups.

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From a ergonomical point of view, it is indispensable to develop the man-machine interface which enables smooth man-machine communication for a system respecting the human sensibility. Previous man-machine interfaces can be assumed as physiological and morphological ones which focus on an ensy use. However, in order to achive smoother man-machine communication, the sensible human interface, which can embody the user's “joy” and “pleasure” is expected. In this study, we attempted to develop a color generating method for garment design by expressing the knowledge of color on a semantic neural network.

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The crystal of p-aminohippuric acid was polymerized in the solid state by annealing at a temperature below its melting point. The reaction was carried out on the p-aminohippuric acid crystal at 170°C for 260 h under reduced pressure. The specimens formed through the thermal solid state polycondensation procedure from original monomer single crystals were examined mainly by means of differential thermal analysis (DTA), X-ray diffractometry and scanning electron microscopic (SEM) observation. In DTA measurements, whereas the endothermic spike peak of a monomer single crystal was observed approximately at 200°C. the endothermic peak of a polymerized specimen appeared approximately at 380°C. The polymerized crystal showed slightly oriented polymer rings in the X-ray diffraction pattern. As the result of SEM observation, the many fibrillar structures were found on the surface of polymerized specimens. In conclusion, it is considered that the single crystal of p-aminohippuric acid was converted into aromatic polyamide crystal by the thermal solid state polycondensation.

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[in Japanese]

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