The relationship between coolness and sensation of comfort was investigated as aerosol spray was applied to the skin. Sensory evaluation, such as Scheffe's method of paired comparison (modified method by Nakaya), was carried out to investigate the difference in coolness between samples of water and ethanol in various concentrations. Subjects were also asked whether or not they experienced the “shittori” sensation, a Japanese term defined as the sensation perceived when individuals feel that their skin is maintaining adequate moisture. The distribution of skin surface temperature before and after spraying was photographed using thermography.
Subjects reported feeling a strong coolness as well as an uncomfortable sensation when the skin surface was moistened using the aerosol spray. The 1/3 (w/w) mixture of water and ethanol was the most preferred ratio for producing a thermal comfort sensation
The ratio of water in the spray was high when the room temperature was 20°C, and coolness was accompanied by the “shittori” sensation

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The almost degraded silk fibers show deformed infrared spectra compared with that of reference silk fibers. In this report, the polarized micro infrared spectroscopy was used to clarify the reason for the deformation of spectrum. Since the polarized light is sensitive to the change in the secondary structure of fibroin molecules, the change in the crystallinity and the peak intensity ratio of spectrum of degraded silk fibers were evaluated. At first, the axis of single silk fiber was set parallel to the polarized light of 90°, and the spectra was measured successively by changing the angle of diamond cell until the final position of 0°, namely perpendicular to the axis of single silk fiber.
As a result of the experiments, it was found that the crystallinity increases with progress in degradation. Furthermore, the crystallinity is higher in the direction for 90° compared with that for 0°. Furthermore, the peak intensity ratio, Amide I/ Amide II, was adopted as the measure of degradation. The measured value was generally higher compared with that of reference silk fibers. The correlation between the crystallinity and Amide I/ Amide II ratio was also investigated.

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Clothing pressure is evaluated by clothing a human body or dummy and measuring pressure using pressure sensors. In order to predict clothing pressure using the experimental tensile properties of knitted fabrics without making actual clothes, we have developed a finite element method involving a numerical model consisting of a “hyper-elastic shell with a truss model”, which expresses anisotropy and nonlinearity as a knitted fabric extension characteristic. In this report we introduce an application example using pants. The clothing pressure values predicted using this computer simulation proved to be very close to the actually measured values.

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Many yarns are made from chemical fibers with various kinds of functional properties, and filament yarn surpasses spun yarn in terms of mechanical properties. However, in this century, “comfort”, “safety”, “user-friendly” and “green” are key concepts. The Food and Agriculture Organization of the United Nations (FAO) officially launched the International Year of Natural Fibers (IYNF) 2009 to celebrate the virtues of cotton, flax, sisal and hemp, and also those of wool, alpaca, camel hair and angora. In order to make effective use of natural fibers and reduce carbon dioxide emission, it is worthwhile to design and develop new spun yarns from vegetable fibers.
It is also known that, in comparison with ring spun yarn, open-end spun yarn is inferior in quality. So, to produce open-end rotor spun yarn with novel functional properties, we investigated how to give it greater extension (and/or stretch), as in synthetic filament yarn. Thus, 100% cotton hollow yarns were produced using a hybrid open-end rotor spinning frame and an experimental covering machine, and the resulting mechanical properties were assessed.

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