Barrier papers move into the flexible packaging market

Across the packaging industry, more companies are rethinking how they protect their products while meeting rising expectations for recyclability. Regulations are tightening at national and EU level. Retailers want packaging that fits cleanly into existing recycling systems. Consumers expect materials that feel simple and responsible to dispose of. And brand owners are searching for a path that balances performance, safety and cost.

Sappi has been developing barrier papers for more than a decade. These papers are mono-material and offer the protection needed for many products, work on existing packaging machines with manageable adjustments, and can be recycled in the paper waste stream.

‘The interest has grown fast in recent years,’ said Gustavo Duarte, head of business development at Sappi Europe. ‘Brand owners want solutions that actually solve their problems, not just ideas that sound good in theory. And they want an alternative to plastic that fits into their real production environment.’

Gustavo says that decisions around new packaging materials revolve around three essential requirements. The first is product protection. All products span many categories – tea, cereals, chocolate, flour, dried fruits and nuts, instant soups, sugar and more – and each has different sensitivities. Some need protection from moisture. Others need a barrier against oxygen or mineral oil.

‘You can’t compromise shelf life under any circumstances,’ he said. ‘If the barrier fails, the product is at risk and the supply chain suffers. So, we test everything carefully and consistently. We measure permeation rates, check moisture resistance, and verify seal strength for grades that need heat sealing.’

The second requirement is the ability to run on existing packaging machines. Many packaging lines were originally designed for plastic films and optimsed over the years, which are strong, flexible, and resistant to tearing. Paper behaves differently, even when it will reach the same performance than plastic.

‘Plastic films are more flexible and forgiving in the process,’ explained Alexander Schröder, product application leader. ‘Paper needs a different kind of care and attention. Tension, heat, and sealing pressure all play a role. But this doesn’t mean customers need new lines. Often it comes down to fine tuning. We are working close with machine manufacturers to help customers see what needs to be adjusted before they switch.’

The third requirement is recyclability. This is one of the main drivers pushing brands toward barrier papers. Today, many plastic based packages end up in mixed waste because they cannot be sorted easily.

‘When a material can go into the paper recycling stream, it changes the whole picture,’ Gustavo said. ‘It makes things easier for consumers. It helps retailers. And it prepares brands for future legal requirements. Recyclability is often the factor that convinces companies to take the next step.’

For years, plastics have dominated flexible packaging because they offer barriers combined with easy sealing. Plain paper cannot provide the same level of protection. Glassine offers some/limited grease resistance, and therefore could be interesting solutions to some applications, but has no moisture barrier and cannot be sealed.

‘Barrier papers give you the mix of sealability and protection that plastic films offer, but with the added benefit of being recyclable as mono-material in the paper waste stream. That is the key difference,’ he continued. ‘Moreover, for applications like stand up pouches and bags, paper’s inherently higher stiffness versus plastics.’

This opens space for paper based solutions in segments long seen as too demanding for paper.

At first glance, barrier papers can appear more expensive than certain plastics. But Gustavo points out that the comparison is rarely straightforward. Plastics range from mono-materials to complex laminates that differ widely in price.

Sappi began producing barrier papers more than 10 years ago and has since built up a broad portfolio. The company uses dispersion based technology that enables the papers to be recycled in the paper waste stream.

Gustavo said, ‘We don’t expect one grade to solve every demands. Instead of oversized standard products, we create papers that meet specific barrier requirements. It makes development faster and gives customers exactly what they need, that is both technically and commercially fit for purpose.’

He believes the broader shift toward paper based flexible packaging will continue and intensify in the upcoming years, particularly as PPWR goes into force.

‘This transition is unfolding step by step,’ he said. ‘But the direction is clear. Consumers want packaging that support recycling and companies further want them to properly, protects the product/goods and works efficiently on their lines without major investment. Barrier papers can do all three. That is why we see more interest every year.’