Unidirectional carbon fiber- or glass fiber- reinforced composites as structure materials have wide applications in many industries. In order to combine the advantages of these two fibers, both carbon fiber and glass fiber are employed as reinforcing elements in single unsaturated polyester resin, and hybrid composites are formed. In this study, the erosion behavior of CF/GFRP and GF/CFRP were investigated at different impact angles (15-90°) and compared with CFRP and GFRP on fiber orientation 90°. The results suggested that CF/GFRP was low erosion wear as compared to GF/CFRP. Scanning electron microscopy was used to characterize the morphology of eroded surfaces. The micrographs revealed that CF and GF were maintained their own erosion behavior in the hybrid composite materials as well in the neat FRP materials. The simple analytical approach was constructed to figure out the theoretic erosion behavior, which were compared to the experimental results. It was confirmed that the erosion behavior of the hybrid composite materials could be predicted by the proposed analytical approach.

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Bust silhouette is one of several very important aesthetic points in the appeal of a women’s body, and it is also well known that an attractive silhouette is influenced by both inner and outer garments. Some odd protrusions can appear in outerwear because of the underlying brassiere, in particular, in spring-into-autumn apparel. As a result, many young Japanese women experience discomfort related to this silhouette. Thus we investigated the relationship between the brassiere and the bust silhouette in knit shirt. The experimental results are as follows: (1) unnatural protrusions result from four causes: the seam, the cup line, the trim lace, and the malformed top part of the brassiere, (2) seamless cup type brassiere makes a contribution to a beautiful bust silhouette, and (3) characteristics of the half-cup type brassiere which produces the worst bust silhouette in knit shirt are the total angle of cup top (B_θU + B_θL) ≤ 155°, the curved height of the under-cup line (B_BL) ≤ 6 mm, and the compression recovery (RC) ≤ 50%.

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In this study, two mesomechanical models, inclusion model and inclusion element model, based on equivalent inclusion method and predictive software tools for the mechanical properties of textile composites have been developed. As the inclusion model, the Mori-Tanaka method and the self-consistent method were employed. The Mori-Tanaka method is fast, good overall accuracy in the low to mid volume fraction range as almost the same as the self-consistent method in which an accurate algorithm has been used for the evaluation of Eshelby’s tensor for anisotropic media. But they loose some micro structural information as yarn segment positions and are not considered in the micromechanics analysis. On the other hand, the inclusion element model can take account of positional information of yarn segments, it is very useful model which covers the imperfection of the inclusion model, insofar the fiber volume fraction is accurately sampled but they need significant sampling times and also need more intensive computational power. Calculation of the mechanical properties using the inclusion element model by homogenization method revealed that the inclusion element model overestimates the elastic properties of out-of-plane because of unconsidered resin plies between adjacent yarns.

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In order to examine the properties of sheepskin for prevention of pressure ulcer, experimental works were carried out using 8 type sheepskin specimens. Applied pressure to sacral region, namely contact pressure, and tissue blood flow in sacral skin of subjects who were stationary state in the dorsal decubitus on the sheepskin specimens were measured at the same time for 40 min with the apparatus equipped with an air-pack type pressure sensor and a Laser-Doppler tissue blood flow meter. Individual average contact pressures obtained from sheep skin specimens put directly on the blank mattress were distributed in wide range of 4.65 kPa to 14.84 kPa, and individual average tissue blood flows were recorded in range of 0.69ml/100ml/min to 2.60ml/100ml/min. Furthermore, the contact pressures decreased considerably and blood flows increased as the surface fiber weight increased from 1330 g/m² to 1600 g/m². On the other hand, in case of the polyurethane mattress developed for prevention of pressure ulcer was overlaid with sheepskin specimen, contact pressures remarkable reduced and standard deviations of blood flow indicated large values. Thus we concluded that overlaying sheepskin on the preventive mattresses of pressure ulcer such as polyurethane mattress is one of the effective measures from a viewpoint of prevention of pressure ulcer.

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Silk is usually dyed at the fabric or yarn stage. It is difficult to dye silk fibers at the cocoon stage because (1) cocoon loses its original shape and (2) dye cannot penetrate easily into the cocoon shell. This study is the first attempt at dyeing cocoons adequately while retaining their shapes. Cocoons were dyed with a reactive dye under various conditions. When the dyeing process was carried out for several hours without a surfactant, the cocoon shells were not dyed adequately from 293 K to 333 K, furthermore at 333 K the silk filaments on the surfaces of the cocoons came loose and were entangled. In contrast, the cocoon shells were almost completely dyed when a surfactant, namely, sodium dodecyl sulfate, was used; in this case, the concentration of the surfactant was greater than the critical micelle concentration. The results suggest that the use of a surfactant and an appropriate temperature are useful for dyeing cocoons.

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