Patent attributes
Disclosed are photoluminescent markings that contain a photoluminescent layer and one or more functional overlayers wherein the photoluminescent marking has an emission signature that lies partly or fully in the infrared region of the electromagnetic spectrum. One functional overlayer conceals the photoluminescent layer and blends into the background or blends with marks that are normally present, without significantly reducing the luminescent intensity of the photoluminescent layer. Another functional overlayer provides photolytic stability to the underlying photoluminescent layer. Also disclosed are functional overlayers that enhance the daytime observability of the infrared emissions. A further functional overlayer prevents the observability of a printed message with the naked eye. A combination of functional overlayers each providing a different function is also included. Also disclosed are a multifunctional overlayer and methods of creating and using the inventive photoluminescent markings as well as objects containing the inventive photoluminescent markings.
