SBIR Phase II: Customized Security Films Harnessing Iridescent Structural Color from Multibounce Optical Interference

The broader impact/commercial potential of this Small Business Innovation Research (SBIR) Phase II project is in the development of optical security films that produce colorful reflections. Counterfeit documents and banknotes undermine U.S. economic and trade relations and place the public at risk. It is estimated that 3.3% of global trade is impacted by counterfeiting, with an associated cost of at least $1.82 trillion. Protection from counterfeiting requires a multi-layered approach with latest technological advancements and innovations in design and printing of optical security features. The microtextured films described in this proposal are based on a special optical mechanism that enables the creation of more color options and visually distinctive color changing appearances. The developed optical security films produce color as white light is reflected from microtextured surfaces. The proposed work brings innovative security features closer to market adoption and sustainable revenue. This project will enhance partnerships between academia and industry in the US and support public education in science and engineering. The proposed project will develop microtextured color-shifting security films. The technological opportunity is in the optical design of precisely engineered microstructured arrays that generate light interference and color-shifting appearance via a multi-reflection mechanism that brings overt security value. The Phase II research objectives comprise visual effect design and innovation; integration with other micro-optical components already in use in overt security for combinatorial optical effect; optimization of the form-factor and cost metrics of microstructured films for currency and ID card applications. The end results will be integrated software and manufacturing processes that will deliver unique color-shifting security feature designs demonstrated to be optically differentiated from competitors, with visual effects tailored to the exact specifications of customers, at a competitive price. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.