PRISMADE LABS has developed an innovative technology to enable this.
They use standard printing machinery with carbon inks to print conductive patterns on almost any substrate (PC, PET, Paper, etc). These conductive patterns act as “touch transformers” converting an input touch signal into a unique signal pattern or signature, which is then read and recognized by a touch sensor like a mobile phone.
The unique signal can then authenticate a card or a product or act as a secure trigger between physical and digital world. The compatibility with standard printing techniques makes this approach widely adoptable in almost any sector where printing is used. The lack of electronic parts, unlike NFC or RIFD tags, makes it lower cost and also environmentally friender, especially in high volume and disposable applications
The technology sits somewhere between a simple low-cost but unsecure QD code and an expensive but secure electronic recognition system
There have already been many examples of commercial success and demonstration including in driving licenses, in marketing compaigns, and in securing bockchain-link collectables, etc
In one interesting example (May 2021), Prismade discuss how it enables the Twich streaming community to security print the physical twin of the their unique digital cards (note: the digital cards can be designed by a member of the Twitch community who has earned enough points). There were, according to Prismade, some 50M digital cards designed by May 2021
For more info about printed electronics join TechBlick on 12-13OCT2022 in the Netherlands