So Many Features, So Little Space

While the banknote industry often laments the limited real estate available on a banknote, tax stamps are typically 10 times smaller than notes. Furthermore, most stamps are required to carry variable data as well as multilevel security features adapted to different users with different authentication capabilities.

Hence the need for security features and barcodes on a tax stamp to be stacked or combined, as much as possible, into a single ink, or other element.

At the recent Tax Stamp & Traceability Forum™ and Optical & Digital Document Security™ conferences, Stefaan D’Hoore and Tom Mitchell of Luminescence Sun Chemical Security (LSCS) presented examples of such combined features, as well as examples of ink-based technologies that are well-suited to tax stamps. This article provides an overview of their presentations.

Bi-, tri-, and quad-fluorescence

Fluorescent inks are among the most

commonly used security features on a tax stamp. For an even more secure solution, inks can be used that reflect different colours when exposed to different UV or IR wavelengths, such as yellow at 254nm, red at 313nm, blue at 365nm, and green at 980nm.