Safety unit for safety document e.g. bank note, has visually inspectable safety feature placing automatically reversible color imprint relative to information pattern in recess, such that pattern is disguised without external stimulus

摘要

The safety unit has a substrate (1) with a recess (3), and an imprint (4) provided on the substrate and adjacent to the recess. A foil (5) covers the recess and forms a search window in the substrate. A visually inspectable safety feature (6) is provided on the film and places an automatically reversible color imprint relative to information pattern, such that the information pattern is disguised without external stimulus and visible recognizability of the pattern is facilitated by the effect of the external stimulus. An independent claim is also included for a method of manufacturing a safety unit.