During these coating processes, protective oxide layers are deposited, producing brilliant colours and excellent efficiency. The spectrum of colours of these anodized surfaces depends on the intensity of the electric voltage. They result in colours covering the whole scale of a rainbow.
During the electro chemical anodizing process, a thin oxide layer is deposited on metallic materials when immersing these in an electrolyte whilst applying an electric voltage. On the incidence of light, these layers show interference colours.
The advantages of anodic oxidation are not only the excellent quality and constancy of colours. With this kind of surface treatment, it is also possible to deposit homogeneous layers with selected colours onto parts of complicated geometry.