A coating agent containing hydrophobic nano-particle and silicone resin or linseed oil was developed. It exhibited highly-hydrophobic property when the content of the particle was 80wt %. Surface profile of the highly water-repellent organic-inorganic hybrid composite film prepared by the coating agent was observed by scanning electron microscopy and surface profile measuring system. No patterned indented structure was generated. It was thought that the highly water-repellent property was derived by the hydrophobic roughness structure. So, the surface of the film had a very unique property. The coating agent was also applied to a coating agent for strain gauge, and showed superior performance under outdoor exposure conditions. This highly water-repellent film surface was also found to be transformed to highly-hydrophilic surface by calcinations. Recently, highly-hydrophilic surfaces have been a topic of great interest, because it may show an antifouling effect. The highly-hydrophilic characteristics of the calcined films ware thus evaluated over 2 years of outdoor exposure. The results showed the highly-hydrophilic characteristics were maintained throughout the test period. However, an antifouling effect was not exhibited, since generations of clusters of grayish stains were observed inside of the film.

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We investigated the structure and dynamics of aqueous dispersed poly (oxyethylene) hydrogenated castor oil (HCO) using modern ESR (electron spin resonance) method in conjunction with ESR slow-tumbling simulation. Various spin probes were used to determine the physicochemical values such as structural orderings and electron spin-lattice relaxation times. The present results provide detailed information about molecular motions of spin probes in the HCO membrane at various temperatures. In addition, the modern ESR methods have been applied for defining the structure of human stratum corneum (SC) lipid. ESR is useful for elucidating structure as well as dynamics of the properties of the SC. Based on the slow-tumbling simulation analysis of the results, the structural orderings of the SC lipid layers were determined as a function of the SC depth. Therefore, the modern ESR spectroscopic technique could provide more interpretable information, which would further understanding of the actual skin SC system.

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