METHOD AND DEVICE FOR THE SECURE PROTECTION OF OFFICIAL DOCUMENTS BY MEANS OF A TRANSPARENT FILM HAVING A SINGLE CONTINUOUS THERMOPLASTIC LAYER

摘要

The invention relates to a method for the secure protection of a surface portion (5) of an official document (9) in which a transparent security film is heat-transferred onto said surface portion. The security film includes a single continuous layer (2) which determines the format thereof and has a thickness of 5 mum to 25 mum, made up of a thermoplastic resin having a glass-transition temperature of 30 °C to 120 °C. A protective device supporting said security film is laminated at a lamination temperature higher than said glass-transition temperature in order to perform the transfer thereof.