METHOD FOR PRODUCING AN ALUMINIUM FOIL WITH INTEGRATED SECURITY FEATURES

摘要

The invention relates to a method for producing an aluminium foil (4) and to an aluminium foil with integrated security features (6). An aluminium foil (4) is rolled down to a thickness of less than 150 μm in a plurality of cold rolling passes, texturing (5a, 5b) that runs in the direction of rolling being induced simultaneously on both surface sides (4a, 4b) of the aluminium foil. In a final cold rolling pass, the aluminium foil is fed to a working roller pair (8), in which, on at least one roller surface (11), the relief-like surface structuring (11a) generated in the direction of rolling by grinding was reduced on the basis of contrast and motif in a region (7) of 10 to 50% relative to the average surface roughness so as to form a motif for a security feature (6) that is transferred to the surface side (2a) of the aluminium foil facing the roller surface. The aluminium foil (1) generated has a glossy appearance on both surface sides (2a, 2b) such that the security feature (6) rises very clearly due to its dull appearance.