GREEN-COLORED PLATINUM AND PLATINUM ALLOY AND THEIR PRODUCTION

摘要

PURPOSE:To increase the adhesive strength of a film and to form a stable, uniform, and high strength green colored layer by applying etching to the surface of a base material composed of platinum (alloy) and forming a strontium titanate film in a vapor phase. CONSTITUTION:Etching is applied to the surface of a base material composed of platinum or platinum alloy, by which ruggedness is previously formed in the surface. Subsequently, a strontium titanate film is formed in a vapor phase. By the above procedure, the formation of a Pt-Ti-O composition between the strontium titanate and the base material can be accelerated, and the adhesive strength of the strontium titanate film to the base material can be increased. By this method, the stable colored platinum and platinum alloy showing green color can be obtained.