COLOUR LASER MARKING METHODS OF SECURITY DOCUMENTS

摘要

A security document precursor including, in order: a) at least one transparent biaxially stretched polyester foil; b) one colourless colour forming layer containing at least an infrared absorber, a colourless dye-precursor and a polymeric binder; and c) a polymeric support; wherein the polymeric binder is copolymer including at least 90 wt % of a chlorinated ethylene and 1 wt % to 10 wt % of vinyl acetate both based on the total weight of the binder. Methods for making the security document precursor are also disclosed.