| CPC C23F 1/20 (2013.01) [C23C 18/32 (2013.01); C23G 1/125 (2013.01)] | 7 Claims |

|
1. A method of surface treatment of aluminum or an aluminum alloy, the method comprising a treatment including: bringing a workpiece having aluminum or an aluminum alloy on its surface into contact with an etchant to etch the workpiece, the etchant comprising at least one zinc compound and at least one fluorine compound, the etchant having a pH of 4.5 to 6.5; and pickling the etched workpiece.
|