中文A coating that keeps printed products hygienic using nothing more toxic than visible light and oxygen sounds like science fiction, yet it is already on the market. Varcotec, a Stuttgart-based manufacturer of high-quality graphic coatings, signed an exclusive agreement at drupa2024 to bring its ‘Lock 3’ antimicrobial dispersion coating to Japan, through publisher Sinsei. The deal underlined how a chance encounter between printing chemistry and hospital research can produce a genuinely novel product.
The idea of harmful germs on menus, in-flight brochures or waiting-room magazines had long preoccupied Joachim Frings, Varcotec’s General Director Sales & Development, but his search for a durable, non-toxic antimicrobial coating for dry-printed surfaces had been unsuccessful for years. The printing industry, he recalls, showed little interest in such a solution, until the coronavirus pandemic changed the calculus entirely.
The breakthrough came when Frings encountered research from Regensburg University Hospital investigating how to reduce infection risk for patients using a solution that employed light-stimulated oxygen to kill hospital germs. ‘I was immediately excited because this new technology did not require any toxic or harmful chemicals and had already been used successfully in complex operations,’ he recalled. Over the following years he experimented with formulations to develop a water-soluble dispersion coating that was invisible, stable and reliably antimicrobial.
After an extensive testing and certification process, Varcotec became the manufacturer of what it describes as the first working water-based antimicrobial dispersion coating that permanently disinfects dry paper and board surfaces. The active form of oxygen has been used routinely in medicine for more than two decades to treat tumours and degenerative diseases, and crucially, resistance, as seen with antibiotics and conventional biocides, does not develop against it.
Lock 3 is effective against bacteria, spores, viruses and fungi. As long as visible light is present and oxygen is available, a permanent disinfectant effect occurs. The light activates the oxygen via a photocatalyst, which then destroys microorganisms that come into contact with the surface. Even on overcast days, ordinary waiting-room lighting is sufficient. Varcotec lists the benefits starkly, a 99.99 percent reduction of micro-organisms under room light, no harmful UV radiation required, no toxic or mutagenic components, no release of toxic chemicals, no odours or aerosols, and suitability for all types of printed products.
For the printing industry, the implications are considerable. Magazines, menus, posters and packaging can all be finished with a coating that actively reduces germ transmission, a feature with obvious appeal in healthcare, hospitality, transport and education settings. Because the chemistry is water-based and free of hazardous substances, it aligns with the sustainability expectations increasingly placed on print.
The Japan agreement also highlights the enduring value of face-to-face trade shows. Varcotec and Sinsei met at drupa, the world’s leading printing technology exhibition, where brand owners, designers and decision-makers converge to exchange ideas. Success stories like this, Frings suggested, underline why direct contact remains irreplaceable for surfacing innovations that might otherwise stay locked inside laboratory walls.
As hygiene expectations stay elevated long after the pandemic, antimicrobial print finishes offer a quiet but powerful differentiator. Lock 3 shows that the future of safe print may depend less on harsh chemicals and more on the elegant physics of light and air.
Source: Based on reporting from drupa blog.
The pandemic permanently raised public expectations around surface hygiene, and printed products, menus, magazines, posters and packaging, are part of that conversation. Coatings that actively reduce microbial load without harsh chemicals meet a demand that has not disappeared even as acute fears receded. Because Lock 3 is water-based and free of toxic or mutagenic components, it aligns with the sustainability expectations increasingly placed on print, avoiding the environmental release associated with some conventional biocides.
The commercial pathway is broader than it first appears. Healthcare settings, where infection control is paramount, are an obvious fit, but so are hospitality, transport and education, anywhere shared printed material circulates. A magazine in a clinic waiting room or a brochure on a plane tray table becomes a lower-risk touchpoint. For printers, an antimicrobial finish is a value-added option that differentiates a product in a crowded market, and because it is applied as a dispersion coating, it can sit within existing finishing workflows.
Limitations remain. The effect depends on visible light and oxygen, so enclosed or dark environments see reduced performance, and the coating protects the printed surface rather than the reader. Nevertheless, Varcotec’s Japan deal illustrates how a printing-industry innovation can cross into new geographies through the right partnership, and how trade shows like drupa remain catalysts for exactly these cross-border collaborations. As hygiene stays part of the spec, light-activated coatings offer a quiet but powerful differentiator rooted in elegant physics rather than harsh chemistry.
Regulatory acceptance will be decisive for uptake. Antimicrobial coatings on food-contact or child-facing materials face scrutiny over safety and claims, so Varcotec’s water-based, non-toxic profile is a strategic asset. Unlike silver-ion systems that can raise environmental and colouration questions, Lock 3 relies on a well-understood medical mechanism, singlet oxygen, which carries no known resistance risk and releases no hazardous residues.
Application is straightforward enough to sit within conventional finishing. The dispersion can be applied as a coating layer over printed sheets or board, meaning printers need not rebuild workflows to offer the feature. Cost remains a factor for high-volume commodity print, but for premium, healthcare, transport and hospitality applications where hygiene is a selling point, the premium is defensible. As research continues into new photoactive formulations, light-activated hygiene looks set to graduate from niche differentiator to a mainstream finishing option across the print industry.
