How was the immune system generated in living beings? What pathways were present to reach the developed immune system seen in mammals in phylogeny? If we could answer the above-mentioned questions appropriately, we would easily understand the complex immune system in our body.

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The prevention of color transfer to cups and clothing is very important in lip color products. A common method of minimizing color transfer is to use a film-forming polymer dissolved in a volatile oil in a lip color formula. However, this approach requires the user to wait several minutes to allow solvent evaporation. The result is often unsatisfactory as color transfer can still take place even after drying. To prevent color transfer effectively without any waiting period, we devised a novel dual approach utilizing over-coating. The first is to reduce the mobility of the lipstick film by a dynamic diffusion of the gelling agent from the over-coating to significantly increase the lipstick film viscosity. This is accomplished by carefully controlling the heat of immersion of the solvent in the over-coating such that its value is lower than that of the lipstick. Secondly, a continuous lipophobic film is formed over the applied lipstick film by allowing a lipophobic materials in the over coating to penetrate into the lipstick film through dynamic migration. Extensive investigations on solubility and heat of immersion of many lipophobic materials revealed polyperfluoromethylisopropylether (PF) to be the most suitable for this purpose. From our infrared spectroscopy studies, we were able to confirm the dynamic migration of both silica and PF into the underlying applied lipstick film, when incorporated into a protective over-coating. We tested our new approach in practical applications by formulating a novel film-former designed to be worn over applied lipstick and found that the film provides perfect and immediate long-lasting color protection without a long waiting period after application.

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It is well known that nail damage such as yellowing, split nails and peeled nails (onychoschisis) are caused by continuous use of nail enamel for a long period. Within serious nail damage, we investigated how to prevent the appearance of split nails and peeled nails. The results showed glycolic acid was effective for those kinds of nail damage.

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This study revealed a new physiological function of 2-pyrrolidone-5-carboxylic acid (L-PCA), which enhanced blood circulation by modulating constitutive nitric oxide (NO) generation. It is well known that NO, generated from L-arginine (L-Arg) by catalysis of NO synthase (NOS), plays a key role in the control of vascular tone and peripheral blood flow. We found a dose-dependent enhancement of constitutive NO generation by L-PCA in the human aortic endothelial cells (HAECs). In contrast, D-PCA had no influence on NO generation. Furthermore, L-PCA stimulated L-Arg uptake into HAECs dose-dependently, while D-PCA had no effect as same as NO generation. The L-Arg uptake and its stimulation by L-PCA to HAECs were suppressed with addition of L-NMMA, an inhibitor for the cationic amino acid transporter (CAT). These results indicated that enhancement of NO generation by L-PCA is due to the increase of L-Arg uptake via the CAT pathway. In conclusion, L-PCA was found to enhance blood circulation by modulating constitutive NO generation. Then we confirmed that the occlusive patch test of L-PCA to the volar forearm skin led the redness of skin, and which in turn enhanced the blood flow temporarily. This new function of L-PCA suggests development of innovative cosmetic products to care for such problematic skin as dark circles under the eyes.

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There are a wide variety of hair styling products with various setting effects. Methyl carboxy betaine/alkyl methacrylate copolymer, vinylpyrrolidone/vinylacetate copolymer, acrylates/diacetoneacrylamide copolymer, etc., are used as hair setting polymers. These synthetic polymers can form films with the volatilization of water or ethanol on the hair surface. Consumers are divided into two groups in terms of their preference. One group, those who are concerned with a good setting effect, want to use a strong hold type hair styling product which contains a polymer that forms a very hard film. The other group, who also prefer a good setting effect, use a soft hold type to avoid an undesirable hair feeling. A noble polymer named “Polyurethane Dispersion” has been developed for the latter. Polyurethane Dispersion is a self-emulsifying polymer containing a urethane bond in its main chain. Film properties of Polyurethane Dispersion are soft and elastic. Therefore, the polymer can give a high setting effect with a good hair feeling. Furthermore, the polymer also shows a good thickening property and a high humidity tolerance. Polyurethane Dispersion is recognized not only as a good thickner but also as an agent that can yield excellent adhesive and setting properties of hair. A styling mousse and a styling gel with this new Polyurethane Dispersion can result in a long-shelf-life product without stickness or flaking. Polyurethane Dispersion is a new hair setting polymer that can give “natural style.”

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The objective of the work was to develop a novel self cross-linking polymer capable of enhancing hair strength with fast and long-lasting effects. Our initial approach was to synthesize a homopolymer possessing reactive alkoxysilyl groups in order to effect chemical cross-linking of the polymer chains on individual hair fiber after application. Such a cross-linking reaction is accelerated by moisture and heat. This methodology proved to be successful to result in the formation of a film with high durability against repeated shampoos. Furthermore, we improved this initial polymer by incorporating other functional groups. In particular, we prepared copolymers of alkoxysilane and (1) methylmethacrylate, to increase the Tg of the polymer, (2) methyl siloxane units, to increase the flexibility, and (3) trimethylammonium units, to enhance the affinity of the polymer to hair. The quaterpolymer containing these four functional groups in suitable ratios was shown to form rapidly a film coated individual hair fiber as an “artificial cuticle, ” improved hair strength without film cracking and smoothed the texture of the hair. The performance of the polymer was evaluated by a bending test to estimate its resilience and the durability against repeated shampoos. Subsequent field tests on human hair confirmed that the formulations containing this polymer succeeded in improving hair manageability and healthy appearance, creating volume, and keeping the hairstyles ideally for an extended time period.

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The application of carboxyl modified silicones as a surfactant was studied. Carboxyl modified silicones, which were neutralized with triethanolamine, were used in this study. The results of a emulsification test of dimethylpolysiloxane indicated that both water-in-oil and oil-in-water emulsions could be prepared by changing carboxyl equivalents. In particular, a high internal phase water-in-oil emulsion was formed by using a high-equivalent carboxyl modified silicone. On the other hand, an aqueous solution of neutralized low-equivalent carboxyl modified silicone showed good detergency for a spot of decamethylcyclopentasiloxane. These results suggest that carboxyl modified silicones are valuable for cosmetics.

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Massage is known to be useful for reducing leg swelling. In the present study, measures to improve the effectiveness of self massage for the treatment of leg swelling were investigated in an attempt to develop a useful cosmetic product. In ten healthy women with subjective symptoms associated with leg swelling, the degree of swelling was assessed using the water displacement method, and the results showed a 2.5% increase in leg volume toward the evening. In these women, after five minutes of self-massage and six minutes of hot-cold therapy, the results revealed a 2.5% decrease in leg volume, thus clarifying that this type of therapy does effectively reduce swelling. Consequently, we attempted to develop a cosmetic product based on hot-cold therapy, and it was found that a “cracking foam” product made by mixing a conventional gel agent and a high concentration of liquefied petroleum gas (LPG) was more effective in alleviating swelling in comparison with the other existing products.

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