Anodic oxidation of the metal piece dyeing method

A method for dyeing anodized metal workpiece, which comprises a colored metal workpiece surface, comprising the steps of: (a) anodizing the metal workpiece, the anodized film to form a colored surface of the metal workpiece, the anodized film film is formed on the aperture; (b) providing a first sealing treatment solution, the metal of the workpiece after a first anodization sealing process, and the time of contacting the anodized film sealing process fluid along a first pre- set gradually changes direction, so that the depth of the pores of the membrane along the predetermined direction gradually changes; and (c) of the staining process after the first metal workpiece after sealing treatment, a metal workpiece after staining. The anodic oxide dyeing method can render the surface gradient, and the process is easy to control, suitable for mass production.