Security printing machine

Machine for security printing on security papers, particularly bank notes, comprising a paper-feed device (1), a paper-transportation device and a unit (19) for applying optically variable images supplied by at least one tape which is brought into contact with the paper such that these images are applied at specific locations on the paper corresponding to printing (impressions) on security papers. The application unit (19) includes at least one activator roll (11) interacting with a pressure roll (20) and between which the paper passes through. The tape is mounted between two reels which are arranged in a sector of the applicator roll (11) and the tape passes along a generatrix of the said applicator roll, perpendicularly to the path of the paper, under the action of a servomotor acting intermittently at each application step.