One solution for this is the water-based printing ink "Finishfit Microbe Protect 2400" developed by printing ink manufacturer Epple Druckfarben AG.
This varnish technology can be applied amongst other things in flexographic and/or gravure printing and is used on different paper substrates.
The antimicrobial and antiviral effect is achieved through an active ingredient that remains active for a long time. Positively charged silver ions are released that actively contribute to the reduction of bacteria and viruses on the surface of the varnish.
The functionality of the active ingredient in the varnish against various bacteria has been tested on print samples according to ISO 22196 and a reduction of up to 99.99% was recorded.
Very recently, a large packaging company used this functional varnish for the coating of protective walls made of corrugated cardboard, which are used as barriers in schools and training establishments where the minimum distance for avoiding droplet infections cannot be maintained.