| abstract |
(57) [Summary] [Purpose] By forming a chemical conversion coating thicker on the bottom surface than on the peripheral wall of the can body, the corrosion resistance of the bottom of the can is improved and the coating stability of the peripheral wall is increased. A method for forming a chemical conversion coating on the surface of an aluminum can body W by forming a chemical conversion coating on the surface of an aluminum can body W, which comprises a cylindrical peripheral wall and a bottom that closes one end of the peripheral wall, At the time of forming, the electric field is formed around the can body W so that the electrode potential on the surface of the can body becomes more noble on the bottom side than on the opening side of the can body. |