METHOD FOR PRODUCING ALUMINIUM FOIL WITH INTEGRATED SECURITY FEATURES Russian patent published in 2016 - IPC B21B1/22 

FIELD: metal processing.

SUBSTANCE: invention relates to rolling aluminium foil. Method includes production of aluminium foil (1), as well as aluminium foil with integrated security features (6); the aluminium foil is rolled to a thickness of less than 150 µm in multiple cold rolling passes and simultaneously a texture (5a, 5b) which runs in the rolling direction is produced on both faces (4a, 4b) of the aluminium foil. Higher reliability of identification of the produced foil and reduced probability of forgery is ensured by the following: at least two aluminium foils (4) form a loose composite (8), which is fed into a pair of working rollers (9) in a final cold rolling pass, wherein on at least one of the surfaces (11) of the pair of working rollers the relief-like surface structure (11a) which is produced in the rolling direction by means of a polishing process has been reduced by 10 to 50% with respect to the average roughness height in one region (6') in a contrast- and motif-dependent manner on at least one roller surface (11) in order to form a motif for a security feature (6). Security feature is transferred onto the aluminium foil face (2a) that faces the roller surface, and the loose composite (8) of aluminium foils (1, 4') is then separated.

EFFECT: higher reliability of identification of the produced foil and reduced probability of forgery.

10 cl, 8 dwg