5th April 2023
While navigating the various sustainable packaging options out there, you may have come across the terms 'dispersion', 'aqueous' or even 'water-based' coating, about how they might be the “future” of recyclable packaging and the “solution” to poor-end-product recyclability and regulatory issues. But are you aware of what these terms actually mean, what the process involves and how it affects the environment when we dispose of these packaging items?
Let's take a step back and break it down.
What is dispersion coating?
Dispersion refers to the process in which small particles of a substance are scattered within another substance. In the case of dispersion barrier coating, the particles of petrochemical-derived polymers are polystyrene or acrylic dispersed in water to create the coating. This results in what is also known as 'water-based dispersion coating', 'aqueous dispersion coating', or 'barrier polymer dispersion coating'.
What sets dispersion coating apart from conventional packaging linings is that it is applied as a liquid on the surface of the cardboard rather than glueing an external layer of plastic film onto the fibre substrate. This is where the myth of its sustainability arises, as it is presented as “plastic-free” since it is not PLA and PE lined, but in fact, still contains plastic polymers as it is made out of particles that derive from it such as polystyrene or acrylic.
So why do some manufacturers market dispersion barrier coating as sustainable and "plastic-free" if it still contains plastic? Simply because the coating can evade the legal definition of plastic or contains less of it, doesn't mean it's not there. We're here to remind you that the environmental impact of dispersion coating is real and shouldn't be ignored.
What is the real environmental impact?
Dispersion coatings are not the solution, but merely a mask for one. As the coating is typically less than 10% in total weight, it will easily pass home composting and paper recycling tests. It focuses on the disintegration of the paper itself rather than the coating — made of such small plastic particles.
However, this approach does not address the underlying issue of plastic waste. Polystyrene and polyacrylates are families of polymers that are derived from petroleum, a non-renewable resource that releases additional carbon onto our environment. These polymers are synthesised in factories which means they don’t occur naturally in the environment. Life on planet Earth has not had time to evolve around plastic, and therefore the end of life of such polymers is problematic. They can persist in the environment for hundreds of years, fragmenting into smaller particles, creating more and more nanoplastics along the way. ..
Dispersion coatings are popular because the resulting food service boxes can be recycled, unlike plastic laminated cardboard. However, each time the coated board goes through the recycling process, the fibres are separated from the coating and recovered, leaving all the microplastic particles in the wastewater effluents from the paper recycling mills which then go straight into our rivers and the ocean. The risk posed by microplastics has already led governments to ban their use in a number of applications such as for cosmetics. Yet, aqueous coatings continue to be promoted as a sustainable alternative without proper oversight or regulation, releasing trillions of micro and nanoplastic particles into our water streams, where they will remain for centuries.
Are dispersion coatings here to stay?
The latest guidance from the EU Single-Use Plastic Directive (SUPD) stipulates that from 2023 aqueous lining can no longer be considered plastic-free due to the presence of these petrochemical polymers. As a result, it must be appropriately labelled for sale and use within the EU to promote responsible disposal practices. The directive also requires drink cups containing any amount of plastic to feature the 'Plastic in Product' turtle logo. For now, aqueous-lined food containers and other similar products can still be used, but it is crucial to dispose of them responsibly.
In March 2023, the EU adopted the Green Claims Directive to combat greenwashing, setting common criteria for sustainability claims made by companies. The directive is based on a 2020 study that found over half of the environmental claims on EU products were vague, misleading, or unfounded. The proposed rules will require minimum criteria around measurability and hopefully put an end to the noncompliant claims around dispersion coatings in EU countries.
In the UK, the Foodservice Packaging Association (FPA) has recently expressed the opinion that these claims are misleading consumers and do not comply with the UK Green Claims Code which is similarly aiming at preventing greenwashing in the industry.
The UK definition of plastic is for now not as virtuous as the EU one. Still, we can hope that it will follow the emerging global definition of plastics and therefore prevent aqueous coating companies from defining their dispersion-coated products as “natural”, “plastic-free” or “compostable” which is adding more confusion to consumers.
Regardless, education on this topic is still very limited and many manufacturers and distributors are not hesitating to push, at best, vague marketing messages and, at worst, purposefully misleading information to continue selling this plastic solution as a sustainable one.
What can we do about it? How can we spot greenwashing?
- Never take it at face value
Never assume that a product is sustainable and "transparent" immediately, stop and consider the messaging of the product.
- Ask questions and the right questions
Ask the manufacturer using dispersion barrier coating what the coating is made from and which substance particles it contains. If they give a vague answer, be more specific and ask if the water-based dispersion contains petrochemical-derived polymers like polystyrene or acrylates.
- Choose Notpla
Our innovative coating is made from naturally occurring polymers extracted from seaweed and plants without any chemical alterations. We believe in implementing the circularity of nature into our products and therefore will never use any petrochemical-derived or synthetic materials in our coating. This ensures that every part of our products biodegrades in weeks, just like a piece of fruit.