A hidden packaging component could boost the circular economy


Single-use plastics have a bad reputation when it comes to durability, and for good reason. Plastics destined for landfill strain the planet’s non-renewable resources and tend to end up in the natural environment rather than in a recycling plant or municipal landfill. Each year, around 8 million tonnes of plastic waste ends up in the oceans from the coast, and when this waste breaks down, microplastics present their own set of challenges.

Despite the negative environmental consequences and pressure from stakeholders to turn away from plastics, companies have reasons to use them. Plastics are strong and durable, and their light weight – compared to metal and glass, for example – means they claim a lower carbon footprint when shipping. On the other hand, plastic is notoriously difficult to recycle. Additives and colorants help form many different varieties of plastic, and not all of them can be reprocessed and recycled with existing technology. Even when plastic is recycled, lower quality material usually results each time it goes through the process.

In short: the case for pursuing a plastics revolution remains, and stakeholders show no signs of letting up their pressure anytime soon.

This hidden packaging component could bring plastics closer to circularity

Making plastics reusable, recyclable or compostable by 2040 could reduce greenhouse gas emissions by 25%, reduce the flow of plastics into the ocean by 80% and create 700,000 jobs, according to the Ellen MacArthur Foundation.

Clearly, realizing this vision in less than two decades will involve everyone in the packaging value chain. The inks and coatings used to give packaging the look and durability it needs are often forgotten in the process, but the careful use of these elements can make the difference in bringing plastics into a circular economy. . Siegwerk, one of the world’s leading manufacturers of inks and coatings, has discovered that these materials can play a central role in every step of the sustainable design process – from reducing plastic use to reusing materials, to more universal and efficient recycling.

“We are a company that has very proactively embarked on the journey to drive and strengthen the sustainable packaging system,” said Alina Marm, Head of Global Sustainability and Circular Economy at Siegwerk, during the Ocean Plastic Virtual Summit in January. “Something as basic as inks and coatings can really pave the way for new circular business models.”

Inks and varnishes in action

In a recent report, Siegwerk outlines the ways in which the smart use of inks and coatings can help reduce material usage, enable packaging reuse and facilitate recycling.

“Shifting from a linear packaging industry to a circular industry can preserve the natural environment and mitigate the effect on ecology, while allowing consumers to continue to experience the benefits of packaging,” wrote Marm in the foreword to the report. “Here, inks and coatings play an important role in realizing circular packaging solutions. Their technical features support the (re)design of packaging by following the three levers of a circular economy – “reduce, reuse and recycle” – helping to keep materials in the loop to maximize their use.

For example, inks and coatings can allow mono-material packaging – which is made from a single material – to perform just as well as alternatives made up of multiple components. This means packaging that is still very effective at protecting, preserving and presenting a product, while being much easier for waste management companies to collect, sort and recycle.

Consider flexible plastic films used for food and product packaging. Although they may appear to be made from a single material, many of these films rely on a coating of polyethylene terephthalate (PET) – the same resin used in plastic beverage bottles – to provide resistance to heat, act as a barrier and give the envelope a glossy finish. But using PET in combination with another type of plastic effectively renders the packaging non-recyclable, as the cost and technical barriers to separating these materials remain high. Enter inks and coatings, which can mimic visual attributes like gloss as well as performance characteristics like precise sealing and barrier function, enabling mono-material films made from unique resins like polypropylene (PP) which are both commercially desirable and easier to recycle.

A more deliberate and strategic use of inks and coatings can also make an efficient recycling process more feasible. Scratch-resistant surface printing, for example, adds to the look of single-ply packaging and can be printed directly onto packaging in a single layer, eliminating the need for adhesives. However, it is important to note that these inks must be fully removable during the recycling process to maintain the purity and value of the end product. In this area, Siegwerk says there is great potential to adapt the hot wash phase that is commonly used in PET recycling to de-ink flexible packaging and ensure that inks and laminates are fully removed so that they do not contaminate plastic bales intended for recycling.

And then we move completely away from plastic. Special coatings – like a barrier that protects contents and extends shelf life, or a layer that eliminates the need for plastic packaging – can make paper a more viable substitute for plastic in more applications. For example, we all know that paper bags tend to get soggy and tear when wet, an area where plastic alternatives have a clear advantage. But the simple addition of a waterproof coating can make that same paper bag usable for many other uses without ending up in a soggy mess. Similar leak-proof liners can be used to replace plastic or wax liners in paper cups and bottles, while grease barriers enable innovations like all-paper fast food packaging that doesn’t rely on plastic seals.

Realizing the full potential of inks and coatings requires coordination

“Creating circular packaging solutions is not just about innovations,” Siegwerk concluded in its report. “This is a collaborative task considering the full life cycle of packaging – from design to use to recycling – to fuel the creation of circularity.”

In other words, bringing plastics closer to circularity requires a systems approach that engages all stakeholders – from manufacturers developing new packaging designs, to brands using them, to consumers and recyclers looking to give them a second life. Soft plastic packaging, for example, is almost universally considered disposable. If new technologies and methods become ubiquitous, public policies and behaviors will also have to change.

“Collaboration, whether at a technical level or at a broader societal level…is fun if you have a learning mindset,” Marm said at the Ocean Plastic Summit. “We really need to innovate collectively.”

This series of articles is sponsored by Siegwerk Druckfarben and produced by the TriplePundit editorial team.

Images courtesy of Siegwerk Druckfarben


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