How mills work with R&D to develop new barrier paper grades

Anne Lahtomäki, Development and Technical Customer Service Engineer, and Esa Saukkonen, Manager of Packaging Portfolio Development

“From screening raw materials and formula development to the commercialisation side, the amount of talent across different fields that was poured into developing the new Confidio grades is immeasurable. Teamwork is key because there are so many variables when it comes to producing a new type of paper,” states Lahtomäki, whose team at the mill discussed the finetuning of the recipe with colleagues at the Northern Europe Research Center (NERC), who also performed the lab tests.

Saukkonen, who oversees the end-use aspect such as the barrier performance in packaging processes, notes that there is a willingness to learn running through the team. “Sometimes I will need more information or data to understand what our chemists in R&D are saying, so it is key to communicate and ask questions. Extra effort is always needed to learn how to produce these papers, especially since everything is constantly changing in the paper-making environment.”

Surging technical competence

One of the changes that led to the development of UPM Confidio was brand owners responding to growing pressure to move from fossil-based to packaging materials based on renewable resources. This demand has, in turn, been driving industry-wide growth in the number of commercially available chemicals, increased knowledge and improvement in heat sealability and barrier performance.

“There have previously been some heat sealability functionality trials at Jämsänkoski that didn’t go so well, but this new approach has vastly different chemistry compared to our one-sided coated products. While some barrier properties are difficult to control on the factory side, we have constant measurements in the lab and control on the machine line to ensure that the quality is what is needed. We must always fulfil everything promised in terms of barrier properties,” stresses Lahtomäki.

Over the last few years, there has also been a surge in technical competence related to packaging end-use and barrier property measurements at UPM Specialty Papers, the majority of which were drawn upon during the development period of Confidio. “The exchange of information and communication between R&D and the factory has been quite intense. New methods to check heat sealability have been developed both in Lappeenranta and at the Jämsänkoski factory, so that has been a learning curve for both sides,” explains Saukkonen.

Along with monthly development meetings, there was at least one person from R&D present during all the factory trials together with the mill personnel. Even though this was challenging during the pandemic, it was maintained because it was a valuable way to exchange information. Researchers could also see first-hand how the barrier coating behaved differently from the pilot in the factory.

Lahtomäki says, “When you are testing formulas or chemicals in the laboratory or during the pilot, and those are working fine, it doesn’t necessarily mean that it will function at the mill scale. A lot of things you wouldn’t imagine can have an effect such as the recyclability of the structure, meaning how it disintegrates or can be repulped. Mill circulation waters are different to those used in R&D operations, plus there are also dissolved and colloidal substances (DCS), which are difficult to mimic on a lab scale.”

Power of customer collaboration

Recyclability is what sets these Confidio grades apart, states Saukkonen: “This product has a high amount of renewable material and supports UPM’s circular economy targets. This stems from the company’s strength of having our R&D department in the same building as pulp and fibre experts. If we develop a new coating cover formula for a chosen base paper, we can easily pre-check the recyclability potential of that final structure before even going to the pilot scale.”

With big brand owners publicly making sustainability commitments, there is a strong demand for high-quality primary and secondary recyclable packaging for dry, greasy, and frozen food products. Both UPM Confidio and UPM Confidio Pro deliver on every level and are also FDA and BfR-compliant, as well as being safe for direct food contact.

To fully test those claims, several brand owners are involved in trialling the paper grades. “Collaboration with the end-users and along the whole packaging value chain of the product has been very powerful. We’ve received valuable feedback and insights into how it performs in food packaging applications, whether something needs to be improved and if the heat sealability is good enough,” explains Saukkonen, who concludes by saying, “We are a very competitive alternative and we’re hoping to see products packed in our UPM Confidio paper grades by the end of this year.”