method for protection against counterfeiting, to ensure authenticity and custom printed sheets.

摘要

PCT No. PCT/IT95/00185 Sec. 371 Date May 6, 1997 Sec. 102(e) Date May 6, 1997 PCT Filed Nov. 14, 1995 PCT Pub. No. WO96/14994 PCT Pub. Date May 23, 1996The method provides the protection or personalization of the pre-printed sheets by impressing microengravings, on all or some of the printed portions of the sheets, through an embossing process carried out on the pre-printed sheets at a temperature higher than the softening point of the dyeing substances used for obtaining the print thereon and followed by a cooling step, said microengravings corresponding to holograms or diffraction patterns or images or words.