Revolution of Recycling: The Role of Washing Processes in Sustainable Packaging

Sustainability is a fundamental principle that drives our innovations and collaborations. As part of our ongoing efforts to promote sustainable packaging solutions, we are revisiting the important topic of deinking. Greiner Packaging considers deinking – which is made possible by hot washing conditions in the recycling process – as a crucial step for improving the recyclability of plastic packaging.

Deinking is the process of removing ink from printed materials, which is essential for clean recyclates. In the context of plastic packaging, deinking involves eliminating printed inks from plastic containers, allowing the resulting material to be reused without contamination of ink particles. This step is vital for producing high-quality recycled plastic that can meet the stringent requirements of food-grade packaging. 

The deinking process offers several significant benefits:

1. Enhanced Recyclate Quality: By removing inks, the recyclate becomes more transparent or white, which is highly desirable for new packaging applications. 
    
2. Regulatory Compliance: Anticipated European Union regulations mandate a certain percentage of recycled content in all plastic packaging, making efficient recycling processes crucial for compliance. 
    
3. Sustainable Production: Clean recyclates reduce the need for virgin plastics, lowering the environmental footprint of packaging production. 

A technique traditionally used in PET bottle recycling – hot caustic washing – involves washing plastic flakes in a hot caustic solution, effectively removing inks and other contaminants. This method is increasingly adopted by PO and PS recyclers as well. Our collaborative research with Siegwerk and Krones has demonstrated the efficacy of this method in deinking printed polypropylene (PP) and polystyrene (PS) cups. 

In laboratory tests, complete ink removal was achieved, with color change values well below the acceptable limit. These results were further validated in industrial-scale trials using Krones' pilot plant, confirming the effectiveness of continuous hot washing processes. 

Our project with Siegwerk and Krones underscores the importance of industry collaboration in advancing recycling technologies. By contributing to the development of standardized deinking protocols like DIN SPEC 91496, we are driving the packaging industry towards a more sustainable future. 

The use of hot caustic washing is essential to achieve high-quality recyclates. Additionally, it is crucial to continuously update the Design for Recycling Guidelines to incorporate new technological capabilities. 

As we continue to innovate, our focus remains on creating packaging solutions that not only meet market demands but also contribute to a sustainable circular economy. Deinking is a pivotal process in this journey, enabling the industry to produce cleaner, high-quality recyclates that can be used in new packaging, thus closing the loop on plastic waste. 

By prioritizing sustainability and leveraging cutting-edge deinking technologies, we are paving the way for a greener future in packaging. For more information on our deinking initiatives and how they can benefit your brand, please contact our team at Greiner Packaging. 

Together, let's make sustainable packaging a reality. 

For further details on our deinking project and sustainable packaging solutions, please reach out to our expert: