Siegwerk, a leading global providers of printing inks and coatings for packaging applications and labels, has secured a new European patent, marking another step in its development of deinking solutions for plastic packaging recycling.

Deinkable mono-material flexible pouch concept combinines expertise of Siegwerk, ExxonMobil, Henkel, Kraus Folie, and Windmöller & Hölscher.

The patented technology covers solvent-based and water-based deinking primer technologies, while Siegwerk's broader deinking portfolio also includes solutions for UV printing applications.

Importance of deinking in plastic packaging recycling

Effective ink removal is particularly important for improving the quality of recovered polymers. Deinking is therefore gaining relevance as a complementary step in mechanical recycling.

Recent CEFLEX research identifies deinking alongside advanced washing, delamination, extraction and dissolution as key technologies for addressing recyclate quality limitations in flexible packaging.

Validated, patented deinking solutions from Siegwerk

Siegwerk recognized early that effective ink removal can improve recyclate quality and has been developing dedicated deinking solutions for printed plastic packaging for several years.

The newly granted European patent protects a primer technology that enables printing inks not deinkable by commercially used conditions to be removed from plastic substrates during recycling, including more complex printed flexible packaging structures.

The functional primer is positioned between the plastic substrate and the printing layer. During alkaline washing, the primer enables the printing layer to be released and removed before the polymer is reprocessed.

The protected concept is not limited to simple surface-printed structures. It also covers constructions in which the ink is located between additional layers, extending its applicability to complex flexible packaging, labels and shrink sleeves.

Siegwerk has validated the technology across different substrates, ink technologies and packaging constructions in its internal deinking laboratory, as well as in collaborative research and industry projects.

One example is the deinkable mono-material flexible pouch concept, with which Siegwerk and partners demonstrated effective print removal during recycling while maintaining the recyclability of the packaging structure and received the German Packaging Award in Gold.

Supporting future recycling requirements through innovation

The new European patent complements US Patent, granted in May 2025, and reflects Siegwerk’s ongoing efforts to develop practical deinking technologies that support the transition towards a circular packaging economy.

For Siegwerk, the patent reflects a broader innovation approach: identifying recycling challenges early and developing practical technologies to address them.

As demand for recycled content grows, Siegwerk’s deinking expertise provides a strong basis for addressing one key factor influencing recyclate quality: the effective removal of printing inks.