Seigwerk introduces deinking primer technologies for labels and sleeves

Siegwerk, one of the leading global providers of printing inks and coatings for packaging applications and labels, recently announced its new development, an improved deinking especially for rigid plastic packaging which substantially aids industrial mechanical recycling.

Beside the already existing water-based deinking primer (officially approved by The Association of Plastic Recyclers (APR)), the deinking primer introduced by Siegwerk is a UV-curing primer that is suitable for pressure sensitive and wrap around labels, shrink sleeves made of Polyolefin- and Polyester-based materials. This development closes a gap as it now allows an inline printing of deinkable materials in a 100% UV- Flexo press setup.

The ecologically conscious customer of today demands higher levels of recyclable plastic packaging that is not thrown away into downcycling streams. This sustainability-conscious demand has driven brand owners to rethink their packaging to switch to 100% recyclable packaging in the near future. “Achieving this 100% packaging circularity requires a sufficient and consistent quality of recyclates,” explains Ralf Leineweber, Head of Global Technology Development at Siegwerk. Deinking of printed packaging material is one - if not the most - viable technology to meet the mechanical recycling requirement in today’s times. Clean and clear recyclates of a suitable quality can reduce the need for virgin plastic material. “That’s why we are committed to support customers with innovative solutions facilitating deinking and thus contribute to establish deinking as industry standard, further improving packaging recyclability and circularity,” adds Guido Lander, Vice President Narrow Web EMEA at Siegwerk.

The procedure to include deinking in the recycling process requires the recyclers to implement a hot washing step first, if not already existing. However, it is critical that this does not negatively impact the recycling process by contaminating the wash water. Besides, the lower the needed washing temperature for deinking the better, as this not only saves energy but also costs. “We consider deinking primers as a key lever for smart deinking of crosslinked ink systems especially at low washing temperatures for sleeves, labels and other printed decoration for rigid plastic packaging,” explains Leineweber. “The greatest opportunities to improve plastic recycling in line with a circular economy obviously lay in areas where hot washing already became a standard step within the recycling process, such as in the PET bottle 2 bottle recycling,” adds Ralf Leineweber. Siegwerk developed deinking technologies for shrink sleeves allowing a 100% recyclability of bottle and sleeve in food contact grade quality. Furthermore, the ink expert sees excellent opportunities to recover high-quality recyclates from postindustrial flexible packaging waste via deinking. Post-consumer waste is supposed to follow as well at a certain time due to its volume related importance.

Siegwerk’s deinking primers are compliant with different film materials like cPET(crystalline polyethylene terephthalate), PE(polyethylene) or PP(polypropylene) and do not require the use of a dedicated ink series,thus keeping complexity for users rather low. Further, any printing process can be used in combination with Siegwerk’s deinking primer portfolio – from flexo, offset and screen printing to foiling, metallic and other decorative embellishments. With the UV-curing deinking primer, the company offers a solution for converters who are using a pure UV flexo press and are not able to process a water-based primer.

This primer shows best compatibility with UV-curing inks facilitating quantitative deinking according to the washing protocols of EPBP (European PET Bottle Platform) and APR (The Association of Plastic Recyclers). Applied under bleeding resistant UV-cured ink layers, the primer layer dissolves in the hot washing process and thus enables the generation of high-quality colorless recyclates, while the non-bleeding ink formulations ensure a clean and reusable washing solution.

Apart from deinking primers, printing inks and coatings, Siegwerk also offers its customers technical services along the value chain to support an optimized and consistent deinking process. The company can also provide optimized deinking chemistry based on a systematic development to ensure fast deinking. This results in clean flakes with an almost virgin quality recyclate.

“Deinking is not a product for us, it is a “Full-Service Offering” where everything needs tie together,” says Lander. “That’s why we follow a holistic approach and also offer the execution of deinking tests according to the most common washing protocols in our specialized laboratories.”

Based on its deinking expertise, Siegwerk can guide customers through the entire process, from the unprinted substrate to the deinked and recycled packaging material, finally helping them in optimizing plastic packaging recycling in line with a circular economy.

In keeping with the company’s philosophy “Ink, Heart & Soul,” Siegwerk seeks long-term cooperation with its business partners. The organization employs some 5,000 people worldwide in more than 30 country organizations and is headquartered in Siegburg near Cologne.