Certain HDPE packaging from P&G and other major brand owners will undergo digital watermarking as part of a plastic recycling initiative happening in France in 2024.  

Partners on the second iteration of the multi-year initiative dubbed HolyGrail — which include the European Brands Association (AIM), the Alliance to End Plastic Waste, Digimarc for digital watermarking and Pellenc ST for optical sorting — announced this month they’re preparing for the French market launch. P&G, L'Oréal and Henkel are the main consumer goods companies participating, and organizers are seeking to recruit more brands.

The system involves adding the watermarks to packaging designs. Once packaging enters the waste stream, it’s identifiable by optical sorters at recycling facilities. Those watermarks can be linked to a cloud-based repository of product attributes, including brand, SKU, packaging composition and more.

While partners seek to extend the system to numerous types of plastics, the initial focus on rigid non-food HDPE containers in France came down to a matchmaking process between brands and recyclers, in terms of which products could be included and processed by participants, explained Judy Moon, vice president of market development and strategic sales at Digimarc.

In France, one Veolia recycling facility will be using the optical sorters that pick up on the watermarking. There, the aim is to sort detergent and cosmetic streams, to be reprocessed into “fit-for-use” detergent and cosmetic rHDPE grades.

This follows semi-industrial testing to validate the digital watermarking technology and detection sorting unit. AIM members provided 125,000 pieces of product packaging representing about 260 different SKUs, with Digimarc and Pellenc ST reporting results in March 2022 suggesting an average detection rate of 99%, ejection rate of 95% and purity of 95%. Later that year, results from a test of a second prototype between Digimarc and Tomra showed an average of 99% detection, 96% ejection and 93% purity, according to a Digimarc spokesperson.

Digimarc pitches brand participation as an opportunity for those companies to gain data and insights into the post-purchase product journey. Moon said brands see potential benefits in increasing the supply of recycled plastic, sharing data with consumers to gain trust around sustainability objectives, or sharing it with producer responsibility organizations.

P&G’s Gian De Belder, technical director for packaging sustainability, said in an emailed statement: “From the inception of this concept through today we made this idea a viable technical achievement; now we just need to put it into practice in market to prove out the impact this technology can make to improve recycling rates and help keep materials in circulation.”

A P&G spokesperson said the pilot will allow the company to learn more about consumer recycling activity, and it hopes to “gain insights that will help to reinforce what is working and identify any gaps in the actual chain of custody from manufacture to recycling so that we can ensure optimal circularity.” Additionally, the company hopes that “by making sorting less of a consumer burden, we might see greater recycling participation in addition to higher quality recycled material.”

In Europe, brands face EU-wide targets for plastic packaging to be easily recyclable, compostable or reusable by 2030. There are “conversations happening” regarding a potential launch in Belgium, Moon said. “We are trying to look at how different types of markets can address different types of product packaging,” she said.

Digimarc is looking to North America as well. Canada’s Circular Plastics Taskforce has tested the technology, with a focus on flexible plastics, efforts that will move forward under the PRFLEX initiative, according to Digimarc. As for the U.S., “We are in very early-stage possible discussions with a few states,” Moon said. “The U.S. market is in some ways so much more complicated, but given all the [upcoming legislation], social pressures and so forth, I think I'm personally expecting to see traction pick up.”