We have become aware of UV protection for skin in recent years. However we haven't been aware of it for hair. Hair is easily exposed to UV, because hair is different from skin in that it doesn't suffer such reactions such as a hot flash or a slight redness. In fact hair is damaged by sunlight slightly in daily life, and this leads to perceptible heavy damage such as split hair ends, broken hairs and a dry feeling. To maintain and preserve non-damaged healthy hair, we believe it is necessary to protect hair from UV exposure in daily life, and prevent the accumulation of damage to hair. In this paper we discuss hair damage due to UV irradiation, a detection method for early stage modification and technology for protecting hair from UV exposure in daily life.

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It is generally possible to estimate a person's age looking at the back of their hands. Most women are concerned about hand roughness and dryness. It has been reported that application of hand creams to the hand resulted in increased water content and decreased water loss. However, other aspects regarding the skin condition of the dorsal hands have not been well studied. Here we first examined the areas of the skin experienced as getting weaker in women from three countries (Japan, Hong Kong and the United States); the level of concern about the skin on the back of the hands was found to be high. Next, 73 female Japanese and Caucasian volunteers aged 30's-50's living in Japan were recruited. Skin parameters such as water content, transepidermal water loss, elasticity, and skin color (red, yellow) were assessed on the back of each hand. The skin elasticity was found to be higher in Japanese women than in Caucasian women, and the values of elasticity decreased with increased age in both Japanese and Caucasian women. Other parameters including water content did not correlate with aging. As elasticity decreased, the b^* value decreased in Japanese women, whereas the hemoglobin index increased in both Japanese and Caucasian women. Next, dorsal hands subjectively classified as “beautiful” and “homely” were selected among volunteers in order to characterize the differences between these two groups. When the skin parameters were compared, beautiful dorsal hands were found to have higher elasticity and brightness, and little redness. We believe that these results may provide insight into how to keep our dorsal hands beautiful.

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In our previous study, a peptide/silicone hybrid functional polymer composed of silk peptide and silicone resin with a hydrophobic alkyl group was investigated for its compatibility and functionality as a cosmetic ingredient. We have found this polymer provides characteristic functions to modify and control various interfacial properties and named it Active Interfacial Modifier (AIM). The AIM which excelled especially in emulsifying ability was named AIM-FN. The following characteristic functions of AIM-FN were reported before. At liquid/liquid interface, AIM-FN worked as an excellent W/O emulsifier. At liquid/solid interfaces, the peptide moiety of AIM-FN attaches to a hydrophilic solid surface and makes it water repellant and water proof. At solid/solid interfaces, AIM-FN gives a non-oily and non-tacky skin feeling as AIM-FN improves the skin/skin surface property. In this study, we conducted a theoretical analysis of AIM-FN, and acquired new knowledge. We have not reported until now the influence that AIM-FN has on pigments. We added pigments in order to investigate the effect of AIM-FN on pigments used for W/O type cosmetics. We confirmed that AIM-FN worked as a dispersing agent at liquid/ solid interfaces, and had functions which suppressed coagulation of pigments at solid/solid interfaces. AIM-FN was found to have a superior dispersing ability for various pigments with surface treatments. Moreover, we confirmed that AIM-FN suppressed the whitening of sunscreen which happens because of the coagulation of pigments. These facts indicate that AIM-FN is able to heighten interparticle repulsion by ionicity and steric repulsion of peptide origin to pigment. Therefore, these are the result of control of AIM-FN for the solid/liquid (pigment/dispersion medium) interface, and the solid/solid (pigment/pigment) interface. Additionally, AIM-FN Dispersion (AIM-FND) which is a mixture of AIM-FN, Dimethicone (2cs), and water was also studied. As compared with conventional emulsifiers and dispersing agents, since AIM-FN is low in viscosity, it has a high degree of usability as a formulator.

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Because axillary odors are generated by specific bacteria (axillary odorous bacteria), existing deodorant agents contain antimicrobial agents. These antimicrobials inhibit the growth of a wide range of skin bacteria, including skin resident bacteria. Axillary odorous bacteria may acquire resistance to antimicrobial agents. Additionally, these antimicrobial agents may not inhibit the growth of unknown axillary odorous bacteria. Thus, new deodorant materials with effective antimicrobial activity are needed. We aimed to isolate new axillary odorous bacteria and explore new materials capable of inhibiting the production of 3-hydroxy-3-methyl-hexanoic acid (HMHA), which is one of the main contributors of axillary odor. We isolated two bacteria, Anaerococcus sp. and Corynebacterium genitalium. We also found that pentagalloylglucose (PGG), extracted and purified from the Chinese Gall plant, inhibited the release of HMHA by both bacteria. An open study was conducted to evaluate the deodorant effects of PGG on the axillary odor and to analyze the HMHA content in the axillary odor gas, which was collected with a newly developed axillary odor-sampling device. The results of the visual analog scale analyses indicate that the PGG solution reduced axillary odors in vivo. However, the HMHA concentration measured by gas chromatography-mass spectrometry (GC/MS) did not significantly decrease after the application of PGG under the present conditions. With respect to the effects of PGG on skin microbiota, PGG application significantly reduced axillary odorous bacteria and caused minimal changes to other axillary microbiota. These results strongly indicate that PGG is a potentially innovative deodorant material that significantly affects odorant bacteria among axillary microbiota.

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The effects of facial cleansing wipes on skin have not been fully investigated. In this study, the effectiveness of these wipes on the removal of excessive sebum and on the improvement of male skin condition was examined. To evaluate the effect of the lotion contained in wet wipes, we prepared standard wet wipes (SWW) including water, ethanol and a surfactant with non-woven fabrics, moisture wet wipes (MWW) including water, ethanol, surfactant and polyol with non-woven fabrics, and non-woven fabric only as dry wipes (DRW). The effectiveness of MWW to remove excessive sebum was comparable to SWW and clearly more effective than DRW. The sebum removal of SWW was as high as that of facial cleansing cream in the forehead area, but it was inferior in the cheek area. Skin conductance was maintained when SWW was used after the first wash, while it was reduced when the face was washed again after the first wash. To further confirm these effects, a continuous application test was held. In subjects using SWW, there were no significant differences in skin conductance values before and after continuous application whereas the values of control subjects without treatment significantly decreased. These results indicate that the use of cleansing wipes prevents worsening of skin condition.

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