The value chain initiative PrintCYC, which aims to develop cost-effective, circular solutions for recycling printed plastic films into near-virgin quality recyclate for the production of new film, is making good progress, the project group reports.
Participants in the project, which launched in March 2019, are collaborating to research and test new ways to use post-industrial waste from printed plastic films in the most cost-effective manner. The project is not exploring deinking technology.
The group currently consists of machine suppliers Brückner Maschinenbau, Kiefel and PackSys Global, the CPP film specialist Profol, the ink manufacturer hubergroup, converting company Constantia Flexibles and recycling technology specialist Erema.
The initiative is being coordinated by Annett Kaeding-Koppers, who is an independent packaging and sustainability consultant.
The first phase of the project yielded PP film and packaging samples made from biaxially oriented PP (BOPP) films containing > 50 % of PP recyclate with nitrocellulose-based ink formulations.
While these results were promising, there was room for improvement in terms of material properties, such as colour, smell and processability, the participants said.
The group then decided to test alternative ink formulations for printing on BOPP and Low Density Polyethylene (LDPE) films. Using a polyurethane-based ink system in flexoprinting resulted in significant improvements in the mechanical recycling process. Due to the high temperature resistance of >240°C of the inks, no volatile by-products, odour or gels were observed. The result was a new class of premium-quality recyclates with colour-stable properties and an energy footprint - according to the first environmental impact assessment - that was smaller that of film produced from virgin material. These recyclates offered excellent processability, and virgin-like blown film, cast film and even biaxially oriented film was able to be produced of a quality even enabling the implementation of 100% recyclate in the inner layer of a three-layer ABA film structure.
During this second phase of the project, packaging formats such as flow packs, trays, yoghurt cups and tubes were produced, demonstrating the feasibility of using rPP and rPE recyclates in processes such as sealing, thermoforming and compression moulding.
Currently, the results of the project, which will be used, among others, or the further development of Design for Recycling Guidelines, are being presented to other value chain stakeholders for evaluation and discussion, after which the next step will be decided.