Patent ID: 7910022
Filing Date: 2011-03-22
Classification: C09K

Abstract:
1. A photoluminescent composition comprising an effective amount of: (a) One or more photoluminescent phosphorescent materials and, (b) One or more photoluminescent fluorescent materials; wherein the one or more photoluminescent phosphorescent materials selectively absorbs and emits electromagnetic energies when charged or activated by either electromagnetic radiation from an excitation source incident upon the composition, or by the emissions of another photoluminescent material, or both, wherein the one or more photoluminescent fluorescent materials selectively absorbs the emission from the one or more photoluminescent materials and emits the electromagnetic energies to give a selected emission signature, such that some or all of the emission signature lies in the infrared portion of the electromagnetic spectrum, the one or more photoluminescent materials being selected so that the emission of one of the one or more photoluminescent phosphorescent/fluorescent materials overlaps with the absorbance of another of the one or more photoluminescent fluorescent/phosphorescent materials, and wherein the selected emission signature is the emission from one or more of the selected photoluminescent fluorescent materials, such emission being essentially unabsorbed by any of the other photoluminescent materials.