| 摘要 |
The invention relates to use of an aqueous composition for pretreating can body stock, whereby an inorganic-organic conversion layer is formed, which effects outstanding sliding behavior of the shaped can body stock and in addition offers an outstanding holding primer for subsequent coating. The invention comprises a process in which can body stock which is deep-drawn to form a half-open can cylinder, before further shaping processes, is contacted with an acidic aqueous composition which contains water-soluble inorganic compounds of Zr, Ti, Si, Hf or Ce, water-soluble polymers having carboxyl groups or hydroxyl groups and also a dispersed wax. Both outer and inner surfaces of metallic can cylinders can be pretreated in the process. The invention also relates to an acidic aqueous composition for use in the pretreatment process, which contains water-soluble polymers selected from condensation products of glycoluril and aldehydes. |
