Water-based flexographic ink using chalcones exhibiting aggregation-induced enhanced emission for anti-counterfeit applications

In pursuit of fluorescent pigments, a pyrene-based chalcone 1-(4-chlorophenyl)-3-(3a¹,6,8a,10a-tetrahydropyrene-1-yl)prop-2-en-1-one (CPP), which exhibited aggregation-induced enhanced emission was synthesized. Water-based eco-friendly flexographic inks were formulated using CPP (in batch ink) and Luminous yellow RG-3 (in standard ink) as pigments. The batch and standard inks were coated on security paper and printed on security and packaging papers as well as boards. The printed substrates displayed yellow fluorescence upon excitation under UV light. The gloss, light-fastness, abrasion resistance and colorimetric values of the batch ink were superior to that of standard ink. The study revealed the potential of CPP as a fluorescent pigment for security printing applications, optical-electronic devices such as transistors, anti-counterfeiting labels, etc.