With its innovative acrylic-free ink formulation for water-based flexo printing, Siegwerk establishes a new approach for sustainable ink design. Measurable sustainability benefits combined with high performance position UniLEAF as a future-ready solution for stakeholders across the packaging value chain.
Siegburg, Germany, April 16, 2026. – Siegwerk, one of the leading global providers of printing inks and coatings for packaging applications and labels, introduces a new acrylic-free ink for water-based flexo printing on paper and board: UniLEAF. With an innovative formulation approach, it delivers substantial gains in renewable content, significant reductions in carbon footprint, improved energy efficiency, and strong alignment with market and regulatory requirements. This makes UniLEAF a valuable solution for converters, printers and brand owners seeking to enhance sustainability while maintaining high performance and operational efficiency.
Innovative Formulation Approach
UniLEAF, which stands for “Low Energy Acrylic Free”, is built on Siegwerk’s widely used UniNATURE product range, which is already formulated with regenerative raw materials. UniLEAF advances this principle to a new level as it completely replaces conventional acrylic resins with polymers derived from regenerative, bio-based raw materials. “This represents a fundamental shift in the formulation of water-based flexo inks,” said Thibaud Liard, Business Unit Head Paper & Board EMEA at Siegwerk. “By removing acrylic resins, UniLEAF breaks with long‑standing industry conventions and establishes a new approach for sustainable ink design.” At the same time, the formulation integrates seamlessly into existing production processes. The bio-based resin system can be incorporated into standard ink-manufacturing operations without requiring major investments in production technology. Manufacturing efficiency and finished-product quality remain unchanged, allowing producers to adopt the innovation without disrupting established workflows.
Measurable Sustainability Benefits
The new formulation concept has been validated during initial industrial trials, where UniLEAF was compared directly with Siegwerk’s own UniNATURE, which is a sustainable and high-performing product series. The results show a remarkable reduction in CO₂ footprint by an additional 50% achieved by UniLEAF, marking a transformative improvement in the sustainability profile of water-based flexo printing inks. This is driven by a major increase in the share of biogenic carbon in the formulation, as UniLEAF more than doubles this share through the complete removal of acrylic resins. UniLEAF offers another significant sustainability advantage through reduced energy consumption during drying. Industrial trials confirm energy savings of more than 15% versus UniNATURE, all while maintaining the same production speed. “With these benefits combined, our new formulation supports converters, printers, and brand owners in meeting their sustainability targets while improving operational costs. At the same time, it helps them prepare for evolving regulatory requirements across the printing and packaging value chain,” said Thomas Lehnen, Head of Technology Paper & Board EMEA at Siegwerk.
About Siegwerk
Siegwerk is one of the leading global manufacturers of printing inks and coatings for packaging applications and labels. Based on 200 years of expertise, we provide customized solutions for all types of packaging needs - from functional and eye-catching to safe and sustainable. As a seventh-generation family business, we have long been aware of our responsibility for future generations. Under the motto “rethINK packaging”, we are therefore actively driving the transformation to a circular economy by developing eco-friendly solutions that enable packaging circularity. Here, 30+ country organizations and ~5,000 employees worldwide ensure consistent high-quality products and customized support around the world