Green board to the rescue?

With the Blue Planet II TV series having pushed packaging waste to the top of the public agenda, it’s no surprise that industry leaders see the drive to substitute plastics with non-plastics as a top priority.

This was cemented in April, when food and drink manufacturers and retailers joined forces in setting ambitious plastic reduction targets. The UK Plastics Pact, launched by the Waste & Resources Action Programme (WRAP), includes the elimination of problematic or unnecessary single-use plastic packaging through redesign, innovation or alternative delivery models by 2025.

But even setting aside these more radical ‘zero plastics’ initiatives, many believe a fundamental shift has taken place in supply-chain attitudes.

“There is a general understanding that we have a problem with recycling plastics,”​ says Tony Hitchin, general manager of ProCarton – the European association representing board and carton manufacturers.

“And then, of course, we have the environmental damage and the media and consumer outcry. I don’t think that’s going away at all. It’s no flash in the pan.” ​

On the face of it, paper and board should be among the prime beneficiaries of any sense of disenchantment in the food and drink industry, with plastics as a principal material or component in packaging.

But beyond the theory, questions persist about whether these apparent concerns are a transient or longer-term phenomenon and, if the latter, whether the fibre-based packaging supply chain is able to step in with solutions of its own.

“Because of the huge publicity and public awareness of the issues around plastics packaging, one of the key tendencies has involved brands looking at alternative materials and solutions – ideally without incurring any additional cost,”​ Hitchin explains.

Others are more cautious in their assessment of any such trend, and of its implications.

At Iggesund Paperboard in Sweden, spokesman Staffan Sjöberg goes as far to say it’s “all a little bit hysterical”.​

‘We need plastics’​

“Everyone working with paperboard packaging knows that we need plastics to make our own materials more efficient – to create a seal against fat, moisture, and so on,” ​he explains.

“You could say that the traditional paperboard pack was created to minimise the use of more costly plastics. If so, those plastics have already been reduced, but now the process is being taken even further.”​

Any decision to switch from plastics to board for a given pack may not depend on the performance of the materials, but on capital and operational costs.

“For a major move of this kind, you will probably need a new packaging line, and there will be plenty of other knock-on effects​,” says Sjöberg. “For these reasons, innovation in packaging tends to progress rather slowly.”​

A further hindrance comes with key functions such as barrier, which paper and board cannot perform alone. While there has been a relentless focus on packaging that is overspecified for a given role, the risk of underspecification is just as real.

“There are examples of grease-resistant, biodegradable board grades used in fast food packaging, but they wouldn’t be the right choice for a chilled ready meal that might be sitting on the shelf for several days,”​ says Hitchin at ProCarton.

As Iggesund makes clear, the pursuit of bio-based alternatives to polyethylene (PE) coatings, for example, has been frustrated by issues of runnability, functionality and cost.

“These bio-based coatings have been very hard to extrude consistently in the past, and research and development​ [R&D] teams have been working at making that easier,” ​says Sjöberg.

“What’s more, these coatings have not been performing as well as PE, while also costing more. The race is on to find the replacement that meets all these challenges.”​

Iggesund first launched its Invercote Bio grade several years ago. It incorporates the Mater-Bi biopolymer from Novamont, Italy, which ensures the virgin board pack is compostable.

Evaluating bioplastics ​

“We opted not to use polylactide​ [PLA], as initially we couldn’t get guarantees that it was free of genetically-modified organisms ​[GMOs],” says Sjöberg. “Now, we use several bioplastic products from Novamont and continuously evaluate bioplastic solutions from them and other manufacturers.”​

Plastics lamination of board, as well as coating, is another area where brand owners are looking for alternatives. AR Metallizing (ARM) specialises in producing metallised paper and board that avoids the use of metallised polyester laminate.

“We’ve been running tests with some major brands,”​ explains chief executive Bart Devos. “We can replace the existing polyester laminate with no impact on the look or feel of the pack.” ​

Repulping for recycling is possible with polyester-laminated board, but less efficient and with a significantly lower yield than an all-paper metallised substrate.

As with biopolymer replacements for PE coating, metallised paper can involve higher material costs for converters and end-users. This is especially the case with so much metallised polyester originating in low-cost Far Eastern markets, says Devos.

“Can you put a price on sustainability?”​ he asks. “If our materials cost, say, 10% more, is it worth it? From the brands’ perspective, and ours, it is.” ​

New customers for ARM include Arla Foods’ Lurpak and – when it comes to unlaminated, metallised papers used as primary packaging – confectionery brands such as Godiva and Mentos. “We have doubled the size of our R&D department,”​ Devos explains.

“Pre- and post-coatings are where a lot of our expertise lies and, given our capabilities in moisture, oxygen and other barriers, we have an even broader market ahead of us.” ​

As the example of ARM demonstrates, some of the most exciting innovation in paper and board packaging has little to do with material characteristics or performance, and everything to do with visual appeal.

“At the premium end of the market, such as luxury drinks brands, converters are installing presses with 16, 17 or 18 stations for elaborate effects, including processes like cold-foiling, which (unlike hot-foiling) can be carried out inline,”​ says Hitchin at ProCarton.

Premium packaging​

“Developments in texture have also been tremendous,”​ he adds. “They’ve probably not been taken up by mainstream food and drink as much as they might have been. But these inexpensive surface effects provide real differentiation.” ​

WestRock carton business Multi Packaging Solutions (MPS) is among those companies detailed by ProCarton, having invested in an 18-station press. This took the form of a Heidelberg Speedmaster, installed last year at its East Kilbride site, complementing an existing 17-station Speedmaster.

These presses allow the converter to integrate effects generated by lithographic and flexographic print in a single pass.

“Multiple flexo units combined with litho allow the cost-effective addition of specialist finishes, speciality embossing and pigment effects​,” says Carol Hammond, vice-president of innovation at MPS. Other options include cold-foiling and combined face and reverse print.

“Premiumisation and cost-effective print embellishment go hand-in-hand with technology developments,”​ she says.

Like others in the supply chain, MPS has been working to develop technologies that allow customers’ packaging to be ‘connected’, in the sense of permitting consumer interaction via mobile devices.

Hammond explains: “Several technologies have been available for many years, including radio-frequency identification ​[RFID] and quick response​ [QR] codes.”​ But the last few years have seen the development of more efficient alternatives, while not requiring branding or designs to be altered. 

For example, MPS can offer SmarterBarcodes, which utilise existing linear code configurations, while image recognition technologies use the shape of the product or the packaging.

Ultimately, with plastics under pressure, Hammond believes that both virgin and recycled board can step into new roles with regard to performance and functionality.

“A significant amount of development work is under way to support the need for functional packaging with a lower environmental impact, and this will require the development of speciality coatings and enhanced recycling techniques,” ​she says.