Sustainability Progress in Bottle Closures

Prototype of a paper closure, supplied by Blue Ocean Closures for an Absolut pilot.

Having spent the last 47 years in consumer goods packaging, it never stops being intriguing and fulfilling to see how clever some of my fellow packaging colleagues are in their quest to improve the lives of the consumer, satisfy bottom lines, and deal with the increasing stresses of the climate crisis. The demands on the packaging industry to reduce, reuse, and recycle have, of course, put a heavy emphasis on packaging sustainability. Despite that or perhaps because of that, some smart folks have managed to push forward and make positive headway within various packaging categories over time. But currently, the one that catches my attention the most is in the realm of threaded closures for bottles. Particularly interesting is the choice of new materials being investigated, tested, and rolled out now in pilot programs in North America and Europe. In my packaging career path, partially spent in the manufacturing of plastic threaded polypropylene closures, I have watched keenly as the industry navigated wave after wave of criticism and pressure. Consumer groups, regulators, and shifting public attitudes have repeatedly pushed packaging into the spotlight, often casting it as the central culprit in broader environmental debates, justifiably or otherwise. To see clever innovative ideas coming forth, such as the advent of 100% PCR materials used for closures and bottles, ensures that the industry is tuning in and reacting as favorably as it can to environmental concerns, where and when possible. Here’s where advancements are looming.

Paper closures: The recent news out of Europe about paper-based threaded closures (for instance, Great Earth on page 30) makes for an even more intriguing discussion about just exactly where packaging, specifically rigid packaging for liquid products, is headed. Can paper-based materials for bottles and closures allow us the comfort of knowing that packaging has finally become truly sustainable? I’m not so sure that’s a safe bet just yet, as paper has to really prove itself in this capacity before we can become smug at cocktail parties when speaking with non-packaging people about all those plastic bottles

simply going away now due to this wonderful invention—paper. Kidding aside, it is a promising concept should those aforementioned smarter-folks-than-me find a suitable way to contain liquids like wine, water, etc., in a paper bottle (without the plastic bladder or liner), topped with a paper threaded closure.

Mono-materials: Added to these potential new sustainable paper-based packaging milestones is the advent of the use of mono-materials for bottle and closure packaging. Last year saw the introduction of the first 100% PET closure designed for use on PET water bottles (read about Origin Materials’ first commercialization of a PET cap with the Power Hydration brand at pwgo.to/9002). The purpose behind this idea is to streamline recycling and reduce contamination in waste facilities caused by the mixing of PE and PP closures with PET and PE bottles, among other materials.

Recycling efficiency: Keeping the cap attached to the bottle ensures both bottle and closure move together through the recycling process, improving circularity. As this becomes the new normal, mono-material packaging could simplify reclamation while enhancing the visual appearance of bottles, thanks to PET closures’ glass-like properties.

EU regulation: Under the EU’s Single-Use Plastics Directive (2019/904), as of July 2024 all single-use beverage containers must have closures that remain attached through recycling. For many following packaging sustainability, this is a major milestone. Loose closures have too often ended up littering beaches, parks, and streets, creating a nuisance for municipalities worldwide.

Tethered cap challenges: Tethered caps, though effective at reducing litter, have frustrated consumers who find them awkward when drinking—sometimes breaking them off entirely. This undermines the intent, so more consumer-friendly designs are in development. Over time, tethered caps will improve PET bottle recyclability in Europe and

eventually North America. As the industry continues to navigate its way through the serious

and ever-challenging demands from both the consumer and the environmentalist (often one and the same), among other vested interests, it does so with a certain trepidation to assure that they and the manufacturers they represent are satisfying all of the people, all of the time. Speaking in jest of course, but that, in some ways, is how it likely appears to industry experts on a daily basis. A simpler solution, of course, would be for consumers to stop consuming, then we would easily solve this problem. I for one, don’t advocate that, as I’m pretty sure I would likely starve.

PW