Security document paper or card has intermediate layer containing starch, clay, polymer or other material that enhances resistance to creasing

摘要

The material consists of two paper webs and an intermediate layer to give enhanced crease-resistance. The intermediate layer contains a substance selected from starches, clays, mineral pigments, organic pigments, latexes, polymers and natural binding agents. At least one of the paper webs contains a watermark, and the intermediate layer contains an authentification element, e.g. optically detectable, comprising iridescent particles, fluorescent, phosphorescent or coloured fibres or particles, or strips. The authentification element can be one that reacts to certain stimuli, such as an electromagnetic field or microwaves, by emitting a signal that is detectable by an adapted apparatus.