Hair components were extracted in order to macroscopically observe the component most involved in formation of permanent waving by thioglycolic acid. In addition, we investigated the influence of treatment with hydrolyzed keratin on permanent wave formation in hair damaged by repeated bleaching treatment. We found that microfibrils is a mandatory component for the desired shape formation of permanent wave by thioglycolic acid, and plays a major role in the shape formation in primary bond than the cuticle and matrix do. Impregnating damaged hair with hydrolyzed keratin resulted in improvement of both permanent waving efficiency and the damage of hair. We hypothesize that hydrolyzed keratin increasing the efficiency of permanent wave formation by maintaining both the shape formation ability of primary bond and the resistance to gravity at the time of secondary bond.

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The human skin is weak-acidic in a healthy condition, so that it is important keeping a slightly acidic skin to suppress the breeding of ill-function microorganisms on skin. In this study, we have applied newly developed weak-acidic PET fabrics for sportswear in order to examine the effect on the pH at skin surface and its consequent condition. Two types of weak-acidic PETs were prepared by chemical modification and subsequent processing, and the skin condition was compared by human subjects wearing the sportswear made of untreated and two weak-acidic PET fabrics. The weak-acidic PET fabrics were found effective to maintain the pH value lower at skin surface. Here the pH value was even lower after exercise than before exercise. The pH value at skin surface did not change before and after exercise in the case of untreated PET fabric. The results indicate that the pH of sweat is buffered by weak-acidic PET and the breeding of ill-function microorganism is suppressed. In fact the generation of foul smell due to the fermentation of sweat components is less detected.

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Three poly(vinyl) alcohol (PVA)/clay composite films, i.e. PVA/smectite(SMT), PVA/montmorillonite(MMT) and PVA/mica (MIC), were prepared from mixtures of an aqueous PVA solution and clay dispersion using the cast and dry method. The PVA/MMT-intercalated composite film exhibited thermal stability higher than the PVA/SMT or PVA/MIC composite film, although SMT or MIC elements were homogeneously dispersed in the original aqueous dispersions. The enhancement of thermal stability of the PVA/MMT composite film is likely to be attributed to the dispersed structure of MMT elements in the PVA matrix and relatively large aspect ratios of the MMT particles.

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