A new method for coloring anodic oxide films on aluminum

Several new methods for coloring anodic oxide films of Al are explained. An oxide film was colored white by the cataphoresis method using an aqueous solution of metal salts as an electrolytic bath. Clear blue color of cobalt oxide was added to the oxide film by means of hydrothermal reactions. Various colors of organic pigments (PY-17, PY-182, PV-19, PB-15, PV-23) can be given to the oxide film by means of PVD (physical vapor deposition). Carbon black color can be added to the oxide film by thermal decomposition of organic pigments (dicyclopentadiene, 1,3-butadiene, isoprene, 1,3,5-cycloheptatoluene) deposited on the surface by means of CVD (chemical vapor deposition). The corrosion resistivity, color fastness to light, hardness, and a few other physical properties of the colored films were tested. 16 ref.--H.O.(Alfed/UK/US).