Chemical Sciences

Title :

Fluorescent pigments for currency application

Area of research :

Chemical Sciences, Material Sciences

Focus area :

Performance Chemicals & Smart Materials

Principal Investigator :

Dr C. Vijayakumar, Senior Scientist, CSIR-National Institute for Interdisciplinary Science and Technology (CSIR-NIIST), Kerala

Timeline Start Year :


Timeline End Year :


Contact info :


Executive Summary :

Objective: The main objective of the project is the indigenous development of ‘invisible’ fluorescent pigments emitting red, yellow, green and blue colors for application in Indian currency. The specific objectives are given below: a) Conversion of currently developed ‘Invisible’ fluorescent dyes at CSIR-NIIST to pigments suitable for currency printing ? Red, blue, green and yellow colors of emissions on 254 and 365 nm irradiation ? Synthesis of core-shell type micro particles of optimized size, with systematic variations in the cores and/or shells b) Optimization of particle size and analysis of thermal stability, acid/alkali/solvent resistance of the pigments c) Analysis of the light fastness of the pigments in the printed from d) Fine-tuning of the pigment composition and optimization of process to scale up at 1Kg level

Summary: Counterfeiting of currency is a global problem resulting in huge economic losses to the nation. Incorporation of invisible flurescent markers in the currency is one of the most important securily features used worldwide for currency authentication. Currently, 'invisible' the fluorescent pigments for printing Indian currency is being imported, which is a threat to the national security. In this context, the indigenous development of such fluorescent pigments is highly essential. CSIR-NIIST have already developed the know-how to prepare the fluorescent dyes in-house with the support of the ongoing CSIR-FTT project . 'Fluorescent Materials for Security Applications' (MLP0028). However, these dyes cannot be used in their native form for currency printing. They have to be converted into stable pigments with good light fastness, chemo-mechanical robustness, and particle size of below 6 microns. We prpose to devlop a generic and scalable pigmentation procedure to convert the already developed dyes into printable pigment compositions that satisfy currency-specific requirements in terms of their particle size, shelf-life, photosatablity, and acid/alkali/solvent resistance. The pigmentation procedure involves the synthesis of microparticles of optimized grain size conataining binders (< 5% by weight) and photo-satabilizers (>2.0% by weight). Different techniques will be optimized for the pupose as per the exact performance parameters define by the user. The pigments will be transformed into printable inks in collaboration with BNP and the formulation will be optimized for every component. The synthesis of fluorescent molecules and pigments will be optimized at 1 kg scale with the support of CSIR-IICT. The process know-how will be transferred to BNP Dewas as the end of the project.

Organizations involved