In this paper, the fundamental technologies related to human and environment-friendly manufacturing and two examples of applications are discussed. The 21st century is said to be the era of environmental protection and many attempts are being made to create a recirculation-based society, which is imparitive for future generations. The starting point in manufacturing beqins by developing fabrication processes that have a minimal burden on the earth, where goods are intended to maintain and improve necessary functions in the daily lives of people. Two concrete examples using surface technology to build healthy and comfortable dwelling spaces are explained. One is hydrothermally solidified mesoporous materials using soil to control indoor humidity autonomously and adsorb VOCs. The other is on anti-stain surface treatment. One of the biggest tasks at home is cleaning around the kitchen area where water is used. Much energy and resources are consumed for removing dirt or stains at home as well as in buildings. An anti-stain surface treatment that resembles the characteristics of a snail shell was applied to the sanitary wear surface to prevent soluble silicic acid scaling from tap water.

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Moisturizing performance is often a very important factor in cosmetics. However, incorporating high concentrations of moisturizing agents often causes products to become sticky, a feel that consumers dislike. We suspected that the reason why high moisturizer content generates strong stickiness is that the polar group of the molecule is exposed to the surface. Thus, we began with the hypothesis that stickiness could be prevented through coexistence with a substance minimizing the exposure of the polar group. Using glycerin as a moisturizing agent, we screened a large number of conventional materials for reducing stickiness but failed to find an effective compound. We then considered the use of a polymer for this purpose, and synthesized a custom-made polymer, polyglycolmethacrylate-2-hydroxyethylmethacrylate-fluoroalkylacrylate copolymer (Polymer SR). Our experiments revealed that Polymer SR reduces the stickiness of glycerin by forming a hydrophobic film without hindering moisturizing performance. To clarify the mechanism by which Polymer SR restrains stickiness, we investigated the interaction between the Polymer SR and glycerin in solution form with NMR and static lightscattering measurements. We learned that Polymer SR and glycerin exist on skin as the hydrophobic group of Polymer SR orients to the outside. Subjective sensory tests supported our belief that this hydrophobic orientation is maintained on the dermal surface even after application to the skin. We believe that our technique for restraining the stickiness of moisturizers can be adopted for use with other substances by taking into account the intended function and feel, and will contribute to future cosmetic research.

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It is known that Blue No. 1 (B1; brilliant blue FCF) in an alkaline solution can be decomposed on heating. However, it is also known that the color tone of B1 when in alkaline solution form does not change at room temperature. In this study, the heating decomposition of B1 in an alkaline solution was examined using liquid chromatography/mass spectrometry (LC/MS) and HPLC. As a result, the generation of ethylamino subsidiary (B1sub-EA) and phenol subsidiary (B1sub-HP) colors that existed in commercial B1 were confirmed. The generation of B1sub-EA was very limited, and most of the decomposition of B1 was B1sub-HP that showed in a purplish-red color. It had been suggested that B1sub-HP should change into an oxocyclohexadienylidene subsidiary color (B1sub-OCD) when in an alkaline solution. It has been suggested that the isomerization of B1 should similarly proceed to the quarter ammonium hydroxide form of cyclohexadienylidene with the same maximum wavelength, The effect of temperature on decomposition was also observed. It is suggested that the color tone of B1 when in an alkaline solution should not change in a short time because the decomposition of B1 is slow at a low temperatures.

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Shaving is one of the daily tasks for most men. However, shaving has caused damage to the skin in many cases. In this study, we observed the skin and beards of 21 men aged from 24 to 62 yr and investigated the influence on the skin and the performance of shaving using three models of electric shavers. As the result, it was found that subjects who have a thicker beard or subjects who take a longer time for shaving tend to have dry skin, rough skin and skin with pigmented spots. On comparison of the three models of electric shavers, one rotary shaver had few instances of TEWL and bleeding. The rotary shaver was the gentlest to the skin of the three models. The other two models were swing shavers. On sensory evaluation, “sharpness of the three models” and “a feeling of close shave” tended to have a linear relation with increase in TEWL and increase in redness. Then it was observed that it is easy to misunderstand the burden on skin with good shaving performance. As it was revealed that the rough skin of a man is mainly caused by shaving in this study, the importance of shaving and skin care to reduce the burden on the skin was shown.

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A rapid and simple method for the screening of tyrosinase inhibitors based on a flow-injection analysis (FIA) method using a spectrophotometric detector is described. An aqueous solution of L-DOPA (5.0×10^-3mol/L) and a 5.0×10^-2mol/L phosphate buffer solution were pumped into the analytical line at a constant flow rate. An aliquot of the tyrosinase solution containing an inhibitor was injected into the phosphate buffer stream by a loop-valve injector, and then it was fed to the spectrophotometric detector through the reaction coil. The absorbance of reaction products was monitored at 475nm. As a result, the peak height of the flow signal was proportional to the enzyme activity unit, ranging from 1 unit/mL to 10 units/mL (r=0.992). The FIA system could measure a sample within 5min. β-Arbutin, L-ascorbic acid, and caffeic acid showed strong inhibition for tyrosinase activity in the method described here.

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