The relationship between the surface profile and the image clearness of paint coatings was studied. The relation between the image clearness and the standard deviation σ of the local slopes on the painted surface could be represented in a simple equation, based on the assumption that the distribution function of the local slopes was the normal distribution. σ values were calculated by the equation with the image clearness values which measured by two different types of apparatus, and compared with σ which was directly measured by schlieren method. The good agreement between these σ values was observed, which proved the propriety of the equation. In addition, the conversion formulas for image clearness values measured in different systems were obtained, and their propriety was also demonstrated.
An algorithm to estimate the spectral reflectance distributions of any object colors, which were given only as colorimetric values (chromaticity coordinate x, y and tristimulus value Y) under a illuminant, have been developed ; the spectral reflectance distributions have been composed of many rectangular distributions which have the same tristimulus value Y as that of the object colors. The colorimetric values given by the composed spectral reflectance distributions to the 8 test colors for specifying color rendering of JIS Z 8726 were examined ; results showed good metamerism indexes between Illuminant C and D65.
Carbon-metal composite particles were prepared by “water-in-oil emulsion method” using ammonia water solutions containing both amphiphilic carbonaceous material and a metal salt such as [Pt (NH3) 4] (OH) 2, Cu (OH) 2, or AgNO3. The results of the X-ray diffraction and electron microscopy indicated that the morphology of spherical carbon-metal composite particles obtained by heattreatment was considerably dependent on the kind of metal salt.