Item-level traceability of tax stamps has gained popularity. While standard visible barcodes deliver the traceability function, invisible barcodes double as a reliable covert security feature provided the taggant material is strictly controlled.

The presentation will focus on the challenges of ink jetting inorganic luminescent materials, employed as covert taggants, to print latent text and barcodes. It will describe the methods of preparing the jet taggant ink, the barcode scanning both in production and in the field, as well as the advantages and limitations of digital printing with ceramic taggants.