Siegwerk to sell Varcotec’s Lock 3 antimicrobial coating

This innovative dispersion varnish is said to be the first of its kind and was developed in cooperation with a spin-off company affiliated with the University of Regensburg, Germany. The antimicrobial effectiveness of this product has already been confirmed by several independent testing institutions.

‘With the integration of Varcotec's innovative product technology, we are adding a unique solution for various applications and packaging industries to our portfolio, thereby once again reinforcing the holistic nature of our offers for the packaging market,’ commented Hanns Martin Kaiser, vice president, paper and board EMEA and liquid food packaging at Siegwerk.

Even if printed surfaces on packaging generally do not constitute a hazard, consumers continue to be exposed to potentially contaminated surfaces. As viruses, bacteria, and fungi exhibit varying survival times, the Lock 3 technology helps to avoid risks of transmitting bacterial and viral infections when products’ printed surfaces are handled by multiple people in a short time.

‘With Lock 3, Varcotec has launched the first antimicrobial dispersion varnish based on the principle of photodynamics in order to reliably reduce the germ loads,’ added Paul Pain, global head of water-based technology at Siegwerk. ‘We are pleased to be able to include this unique product innovation in our portfolio, allowing us to offer this to our customers as partner of Varcotec.’

‘Until now, it has not been possible to apply a reliable coating onto absorbent substances, such as paper and cardboard, which would continuously and permanently destroy those germs,’ explained Joachim Frings, sales and development at Varcotec. ‘With Lock 3 we have succeeded in developing a varnish system which can demonstrably reduce the germ load on a wide range of printed products, already at ambient lighting conditions.’

The water-based overprint varnish Lock 3 allows for permanent, independent disinfection of the printed surface under ambient room lighting or in open daylight. Lock 3 contains a patented substance, taking advantage of the principle of photodynamics: the photocatalyst is activated by visible light and transfers the energy thus absorbing the surrounding oxygen. This process creates so-called singlet oxygen, efficiently killing germs by oxidizing their shells.

Tests have shown that Lock 3 varnishes can kill both bacteria (according to ISO 22196 (mod.) for paper and cardboard) and infectious viral particulates (based on ISO 21702 (mod.)) by more than 99 percent. Additional tests against other virus strains, including three members of the Coronavirus family, are currently in the testing phase.

Lock 3 can already be applied to paper and cardboard by means of all commonly used printing machinery and coating equipment. The first pilot applications on plastic films are already underway, an expansion of the application range is under development and subjected to the required testing.

Siegwerk will commence marketing Varcotec's Lock 3 products starting from June 2020 in Germany, gradually phasing it out across countries in EMEA by the end of this year.