In recent years, there has been a notable surge in demand for transparent and white recyclates, driven by brands’ heightened focus on sustainability and impending EU regulations mandating recycled content in plastic packaging. Reports from the Ellen MacArthur Foundation and the European Union’s Packaging and Packaging Waste Regulation (PPWR) underscore the critical necessity of a consistent supply of uncolored recyclates. In response, updates to the Design for Recycling Guidelines now recommend minimizing non-separable decorations on rigid containers. This strategic shift aims to enhance the recyclability of materials such as white and natural polyolefin (PO) and polystyrene (PS) packaging.
Siegwerk has emerged as a pioneer in this field by launching a groundbreaking project to explore the recycling potential of these materials. Central to this initiative is the investigation of hot caustic washing processes, widely established in PET bottle recycling and increasingly applied to PO and PS streams. These rigorous washing methods enhance recyclate quality and show potential in ink removal, supported by the EuPIA’s stance on deinking plastic packaging waste.
Deinking for PP, and PS Recycling
Andreas Kulawig, Department Manager of Application Technology at Siegwerk Druckfarben AG & Co KGaA, shared details of the project with Greiner with Ben during his visit to the lab. He outlined, “Our collaboration commenced with lab tests on PP and PS cups at Siegwerk’s facilities, adhering to DIN SPEC 91496 standards. These tests effectively eliminated all ink, achieving ∆E values between 0.5-1.5, well below the acceptable limit of 3. Encouraged by these outcomes, our next step was to validate our findings under industrial conditions.”
Deinking Project
Siegwerk, Greiner Packaging, and Krones are leading a collaborative effort to revolutionize recycling by converting “non-recyclable” direct-printed white PP and PS cups into high-quality recyclates. Using hot caustic washing, traditionally used in PET bottle recycling and now adapted for PO and PS rigid streams, they efficiently de-ink and transform these containers into white recyclates without altering ink formulations or print designs but by using Siegwerk´s CIRKIT Wash 01 as detergent developed for effective deinking at lowest possible temperature giving almost virgin like deinked recyclate. This achievement highlights the need for recycling guidelines to keep pace with technological advancements, promoting more sustainable packaging solutions.
Collaboration and Innovation
Andrey Charkovskiy, senior business partner at Siegwerk, emphasized, “Achieving packaging circularity in Europe requires cooperation across the value chain. Design for Recycling Guidelines must evolve to recognize advancements in recycling technology. Initiatives like the DIN SPEC 91496 standardized deinking test protocol are essential and should be acknowledged at the EU level.”
The effective deinking of PP and PS direct-printed cups using hot caustic washing underscores the pressing need for Design for Recycling Guidelines to adapt to evolving industrial practices. This project serves as a case study highlighting the broader necessity for similar initiatives, particularly in flexible packaging where non-deinkable systems pose ongoing challenges. Aligning recycling policies with cutting-edge industrial capabilities ensures that technological advancements are maximized, propelling the industry toward a sustainable circular economy.
This initiative exemplifies how collaborative efforts and updated guidelines can enable a more sustainable future in plastic recycling. Siegwerk’s advanced deinking process at their Siegburg lab marks a crucial stride in achieving high-quality recyclates and advancing circular economy objectives.
Disha, Circular Economy Strategy and Program Manager, emphasized Siegwerk’s commitment to enhancing packaging recyclability and improving recyclate quality, stating, “Inks and coatings are pivotal beyond color. Siegwerk is dedicated to pioneering solutions that enhance the recyclability of packaging materials. Plastic deinking is pivotal in our recycling strategy, and our state-of-the-art deinking lab in Siegburg is pivotal in developing and testing innovative solutions.” Highlighting Siegwerk’s collaborative approach across the global value chain, Disha added, “We strongly advocate collaboration with stakeholders.