Printed Multilayer Microtaggants with Phase Change Nanoparticles for Enhanced Labeling Security

Abstract

There is an urgent need to develop taggants that can be used to identify objects, prevent fraud, and deter counterfeiting with high reliability, high capacity, and minimal effort. This paper describes a new multilayer covert taggant based on phase change nanoparticles (metals and eutectic alloys). A panel of selected nanoparticles with different melting temperatures have been added in matrix materials together with fluorescent dye and printed on substrates to form micro-/macrofeatures that contain thermal, fluorescence signature, and structural components. The multilayer taggants can greatly enhance security level for many commercial and forensic applications by their extremely large labeling capacity, coding readiness, and covertness.