COMBINED MULTI-SPECTRAL DOCUMENT MARKINGS

摘要

A document printed marking including a first information marking including first luminescent taggants having a first luminescence wavelength band; and a second information marking printed at least partially on the first informati on marking at an overlap location. The second information marking includes second different luminescent taggant having a second different luminescence wavelength band. The second luminescence wavelength band is spaced from the first luminescence wavelength band such that the first information marking and the second information marking are substantially luminescently non-intrusive with each other at the overlap location.