SECURITY DOCUMENT INCORPORATING A TRANSPARENT INFRARED ABSORBING MATERIAL

摘要

A security document including a transparent window, wherein an infrared absorbing material is applied to or incorporated within the window. The infrared absorbing material includes at least one infrared absorbing dye supported on nanoparticles having an average size not greater than 100nm. The dye-supporting nanoparticles may be dispersed in a carrier vehicle such that the infrared absorbing material is substantially transparent to visible radiation.