Digital watermarks for effective recycling of plastic packaging.
We have been closely following this trend since our first attempts at digital watermarking for smart packaging. We ourselves were involved in the early implementation of the NETTO brand discounter with the Digimarc and have supervised various design projects. However, the full potential of the idea only unfolds in the network – along the entire value chain. With the so-called “HolyGrail 2.0” (or 3.0 or 4.0), a technology that could make a decisive contribution to the circular economy has become ready for series production for the “tomorrow”.
Image source: Digitalwatermarks.eu
The Holy Grail 2.0 digital watermarking initiative, driven by AIM – European Brands Association and supported by the Alliance to End Plastic Waste, is a pilot project with the aim of proving the technical feasibility of digital watermarks for the accurate sorting of packaging waste and the economic viability of the business model on a large scale.
Digital watermarks are imperceptible codes the size of a postage stamp that cover the surface of a consumer product package and carry a variety of attributes. Once the packages enter a waste sorting facility, the digital watermark should be able to be detected and decoded by a high-resolution camera at the sorting facility, which is then able to sort the packages into the appropriate streams based on the transmitted characteristics (e.g., food vs. non-food). This would lead to better and more accurate sorting streams and thus higher quality recyclates that would benefit the entire packaging value chain.
In 2024, it entered the final phase of R&D trials to validate the technology of intelligent packaging sorting based on digital watermarks. Initial findings were shared at the Sustainable Packaging Summit in Amsterdam in November 2024: The technology was able to show good results in the sorting facilities, with a high detection rate for flex packaging and rigid plastics. However, there are hurdles due to the pending ESFA approval and the higher level of participation required from the major brands to make the system viable. There are also still open questions regarding data management and security.
Our conclusion: Sorting is the most important factor for more efficient recycling – like the experts in the Holy Grail working group, we see the greatest potential in a technology mix of NIR, AI sorting and digital watermarks. It remains exciting!