ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Pyrene-naphthalimide Schiff base as a fluorescent pigment in water-based security ink

R. S. Bhagya, Kashmitha Muthamma, Dhanya Sunil, Prakasha Shetty, and Suresh D. Kulkarni

Department of Media Technology, Manipal Institute of Technology, Manipal Academy of Higher Education, Manipal, India

E-mail: prakash.shetty@manipal.edu

Received: 18 December 2022  Accepted: 11 April 2023

Abstract:

Fluorescence-based materials that are affordable and easy to use for commercial anti-counterfeiting applications are in high demand. While exploring new fluorescent pigments, a pyrene-naphthalimide Schiff base, 5-hydroxy-2-((pyren-1-ylmethylene)amino)-1H-benzo[de]isoquinoline-1,3(2H)-dione (NHPY) with yellow fluorescence under UV light was synthesized. An eco-friendly flexographic ink prepared with NHPY as the pigment was coated on a UV dull paper and further printed on security paper as well as packaging papers and boards. When exposed to UV light, the printed samples showed yellow fluorescence. The light fastness, gloss, colorimetric results, and abrasion resistance of the printed samples proved that NHPY is a suitable fluorescent pigment for security printing applications.

Keywords: Fluorescent pigment; Water-based security ink; Flexographic prints; Anti-counterfeiting

Full paper is available at www.springerlink.com.

DOI: 10.1007/s11696-023-02827-y

Chemical Papers 77 (9) 4905–4912 (2023)