Patrik Willi Hoffmann, Tristan Bret
A process for providing a security paper, in particular a banknote, with a coloured marking, comprising providing a photosensitive preparation on a portion of said document and submitting at least selected areas of said portion to a light beam, wherein sai ...
KBA GIORI SA (SKBA) HOFFMAN P (HOFF-Individual) BRET T (BRET-Individual) MOREAU V (MORE-Individual)2003