Advanced Materials for Banknote Applications
Bruce A. Hardwick, Wen‐Ai Jackson, Gregory J. Wilson, Ada Mau · Advanced Materials · 2001
Australia has spearheaded the worldwide struggle against counterfeiting banknotes over the past 30 years. In the first stage polymer banknotes with transparent windows that contain an optically variable devices (OVDs) were issued. New developments comprise (a) the “self-veryfying banknote” where the interaction of features imprinted in the window e.g., an optical lens, and in another region of the note e.g., microtext only legible under this lens, prove the banknote's authenticity, (b) elaborate inks which for example reveal hidden images under special angles or light intensity, and diffractive OVD elements. Despite the great progress made, the quest for more forgery-proof money remains a continuing effort.