FABRICATION PROCESS FOR METAL-POLYMER CONSTRUCTION

摘要

The invention is relating to a process of rolling the brim of a can of a metal-plastic-metal construction on a small diameter without provoking a crack in the metal layer (3) in the course of this folding operation. This process consists of reducing locally the thickness of plastic (2) in the zone (5) or (6) being rolled in order that the construction reduced to a thin layer of plastic (2) between two foils (3) and (4) of metal behaves nearly as a foil of homogeneous metal. The plastic flowed toward outside of the zone intended to be rolled forms a bulge either towards the exterior of this zone (7) or towards the interior (18). The process applies to food cans and to beverage cans of a metal-plastic-metal construction, as well as to the ends of these cans. The can bodies and ends fabricated by the process constitute equally an object of the invention.