Single excitable dual emissive novel luminescent pigment to generate advanced security features for anti-counterfeiting applications
A novel strategy has been devised to develop a single excitable dual emissive luminescent pigment for the formulation of unclonable security ink. This new advanced security features of the ink have been demonstrated successfully makes it highly suitable for the printing of the valuable products, viz., currency, passports, pharmaceuticals, etc. for their protection against duplicity. The formulation of single excitable dual emissive luminescent pigment is based on the unexplored combinatory concept of fluorescence@phosphorescence phenomenon, which provides a new feature to the composite. It emits intense red color (611 nm) upon 254 nm excitation source and long persisting green color (532 nm) when the excitation source is switched off. To study the feasibility of single excitable dual emissive luminescent security ink for commercial applications, the patterns printed by using this ink are not only subjected to rigorous atmospheric conditions like hot, cold and humid for six months, but also examined against various bleaching agents (ethyl alcohol, ethyl acetate, xylene, acetone, soap solution and laundry detergent) to ensure their chemical stability. The security features printed by single excitable dual emissive luminescent security ink are found to be well stable against all these stringent conditions. Hence, the exceptional result of single excitable dual emissive luminescent security ink offers a new stepping stone against counterfeiting by generating advanced security features.