PIGMENTS HAVING A VIEWING ANGLE DEPENDENT SHIFT OF COLOR, METHOD OF MAKING, USE AND COATING COMPOSITION OF SAID PIGMENTS

摘要

The invention describes luminescent optically variable pigments (OVP), methods for obtaining such pigments, as well as the use of such pigments as security elements in inks, coatings and articles. The luminescence centers are preferably incorporated into the dielectric material of the OVP's opticalFabry-Perot resonance cavity, allowing for the machine-discrimination of luminescent OVP from simple mixtures of luminescents and non-luminescent OVP.