When paper meets high-tech flexo printing, the result is more than a sheet of material – it’s a manifesto for sustainable packaging. Uteco, in collaboration with Dr Kai Lankinen, UPM Specialty Papers and Siegwerk, has taken a bold step forward, proving that functional barrier coatings can be printed directly onto paper, eliminating plastics without compromising performance.

In the sun-drenched demo centre of Uteco in Verona, Italy, temperatures soared close to 40°C, humidity levels tested even the sturdiest water-based inks and yet the Uteco OnyxGO eight-colour flexographic press hummed with cool confidence. It was here, amid the heat of an Italian summer and the precision of industrial machinery, that the future of paper packaging was being printed – layer by layer, coating by coating.

Dr Kai Lankinen, a luminary in packaging printing, partnered with UPM Specialty Papers and Siegwerk to explore a simple yet revolutionary question: could flexographic printing apply functional barrier coatings directly onto paper, producing a material fit for food packaging without a single trace of plastic? The answer, their trials revealed, is a resounding yes.

For decades, replacing plastic in packaging has been more theory than reality. Moisture, oil and heat resistance have demanded multilayered constructions or extrusion coatings, each layer adding cost, complexity and environmental burden. The OnyxGO trials offered a compelling alternative: apply water-based dispersion barrier coatings at the printing stage itself. This goes beyond incremental innovation – it marks a paradigm shift. With the right configuration, a sheet of paper could resist water, fend off oil and even support heat-seal applications – functionalities once reserved for plastic-laden composites.

The trials were far from controlled laboratory experiments. They were industrial stress tests conducted in real-world conditions. The press ran at production speeds during blistering summer days, proving that advanced water-based coatings could survive – and thrive – under harsh operational environments. Such validation under extreme conditions is crucial for converters and brand owners considering a transition away from plastic.

UPM Specialty Papers supplied three distinct grades: Solide™ Lucent, Asendo™ and Asendo™ Pro. Each paper brought unique characteristics, from untreated sheets to those without heat-seal properties. Siegwerk contributed its CIRKIT BAR SEAL range of overprint varnishes, meticulously engineered to explore a spectrum of barrier performance. Multiple layer configurations and coating weights were trialled, revealing a versatility that would allow converters to tailor barrier properties to specific packaging requirements.

Early observations are promising. Even preliminary results demonstrated marked improvements in water and oil resistance, a feat long considered challenging for paper alone. Laboratory analysis continues to fine-tune the exact coating weights and barrier efficiencies, but one fact is already clear: the concept works. Every coating trialled meets strict food-contact regulations, a vital criterion for the ever-expanding sustainable packaging sector.

The implications for the industry are profound. Flexo-printed barrier coatings are no longer a futuristic concept but a tangible, scalable solution. Eliminating an extra layer of plastic film or extrusion coating reduces material usage, simplifies supply chains and aligns with increasingly stringent regulatory and sustainability goals. For converters, it means production flexibility; for brand owners, it means packaging that communicates environmental responsibility without compromise; and for consumers, it signals a shift towards packaging that reflects the values they increasingly demand.

Central to this achievement is Uteco’s unique ecosystem: the Technical Centre, the high-performance OnyxGO press and a team with deep technical expertise. By providing a real-world production environment for these complex trials, Uteco acted as both enabler and innovator, demonstrating that flexographic printing can deliver on sustainability without sacrificing speed or reliability.

Project success

What sets this project apart is both the technical accomplishment and the broader vision it embodies. In an era when sustainability is imperative, the collaboration between Dr Lankinen, UPM, Siegwerk and Uteco represents a roadmap for the packaging industry. It shows that with the right technology, ingenuity and partnership, fibre-based materials can meet – and even exceed – the functional demands traditionally handled by plastics.

Looking ahead, the Uteco OnyxGO’s achievements signal opportunities beyond paper alone. Flexo-printed barrier coatings open doors to customisable packaging solutions, where each print run can be tuned for specific performance requirements. They also offer a platform for brands to differentiate themselves in a crowded marketplace: packaging that is not just visually compelling but materially responsible.

Uteco will highlight this innovation at K 2025 (4/B30), demonstrating firsthand how flexo printing can drive sustainable transformation in flexible packaging. Visitors will witness the seamless fusion of speed, precision and environmental consciousness, all rolled into one press.

As the packaging landscape evolves under regulatory pressure and heightened consumer awareness, projects like these underscore a fundamental truth: innovation in materials and processes is essential. With the OnyxGO trials, Uteco has illuminated a path forward, proving that sustainability and functionality can coexist, and that the future of packaging is not just green but printed with intelligence, precision and purpose.

In the end, what emerges from the OnyxGO is more than a sheet of paper coated with protective layers – it’s a statement that technology, creativity and collaboration can converge to redefine an industry long dominated by plastics.

Ed’s note: Uteco is represented and distributed in South Africa by Sareltech.