摘要 |
1,204,701. Anodizing aluminium. ALGRAPHY Ltd. July 11, 1968 [Aug. 9, 1967], No.36525/67. Heading C7B. In anodizing aluminium a more uniform film thickness is achieved by disposing an apertured plastics material between anode and cathode. As described two aluminium sheets to be used as lithographic printing plates are arranged parallel to another in a bath of dilute sulphuric acid and connected as anodes, lead sheets serving as cathodes are disposed adjacent the walls of the cell tank parallel to and sandwiching the aluminium sheets, and “ inch mesh polyethylene gauze is disposed adjacent to each cathode on the anodefacing sides. The anodizing current density may be 40 amps./sq. ft. |