In the cosmetic industry, many inorganic powders are used, and for their easy handling and improvement of functional properties of the powders, various things are demanded. Generally, powder characteristics and surface phenomena concerning the inorganic powders depend largly on their surface properties. Therefore, surface characterization of powder particles is very important to clarify the mechanisms of powder phenomena, and to use effecively the powders. At the surface of the powders, continuity of chemical bond disappears and the surface property becomes more active according to its unsaturate degree.
In this paper, physical and chemical states of real surface, for examples surface conductivity, adhesion, acid-base, and oxidation-reduction properties are discussed in relation to the peculiar nature of the solid surface.
