DS Smith’s Surface and Barrier director discusses next-gen coatings for fiber-based packaging

Barrier coating innovation is crucial to the packaging industry’s “paperization shift” amid increasingly stringent waste management regulation and growing consumer demand for plastic alternatives. However, biomass or natural polymer alternatives must match conventional plastics in performance and cost-effectiveness, which can be challenging.

Packaging Insights sits down with Susana Aucejo, Surface and Barrier director at DS Smith, to understand how these challenges might be overcome and why barrier coating innovation is crucial to the industry’s drive toward great environmental sustainability.

Why is barrier coating innovation currently such an important focus for packaging suppliers?
Aucejo: The packaging industry is facing a tremendous challenge to fulfil the sustainability agenda. There is an increasing number of legislative initiatives in Europe to tackle plastic waste and improve recycling rates, such as the EU Packaging and Packaging Waste Regulation (PPWR), which was recently approved.

Markets and legislation are pushing for companies like ours to help customers deliver on plastic replacement by using naturally occurring materials — or, at the very least, reduced plastic input. Consumers want to buy less plastic but maintain the same functional capabilities in the products they buy.

Some material properties need to be improved to replace plastic packaging with fiber-based material such as corrugated cardboard. Fiber-based material is porous, allowing gases and elements to pass through, so we must use different barriers as part of the makeup of our material.Susana Aucejo, Surface and Barrier director at DS Smith: “There are more and more developments to replace oil-based barriers with innovative options from biomass or natural polymers.”

Replacing plastics as a packaging material is not that simple — creating packaging products and solutions is a part of a very complex process that ensures protection and effective delivery throughout a supply chain cycle. During this complex process, there are many interactions between the environment, packaging and product. The environment contains components such as water vapor and oxygen, which can enter and leave the packaging depending on the material’s permeability. These effects can lead to product deterioration — hence, there is a need to create and leave a barrier on certain packaging solutions.

In what ways can new barrier coatings support the industry’s drive toward greater environmental sustainability?
Aucejo: New barrier materials will support the packaging industry in different ways. Firstly, barrier layers can help by reducing the need for plastic layers in packaging and, therefore, also lessen the overall use of fossil fuel-based materials.

In addition, effective barrier materials can help preserve food longer, extending shelf life and reducing spoilage and food waste. The use of sustainable barrier technology in fiber-based packaging solutions can also help simplify manufacturing and, therefore, support the requirement for less energy in the manufacturing process.

Finally, barrier developments are helping the industry to comply with stricter regulations on packaging materials.

How are you developing more effective barrier coatings, and what challenges are you working to overcome?
Aucejo: The corrugated cardboard material and product can be protected from water, moisture and grease, but we can also protect the product from abrasion or static electricity — we can add different functionalizations.

Due to pressure from legislation and market needs, there are more and more developments to replace these oil-based barriers with innovative new options from biomass or natural polymers. Consequently, we are also working on solutions that will eventually be seen as the next generation of barrier materials.

We are testing new coatings and new application technologies to provide as many sustainable solutions as possible. We develop our own products but also work with different universities and research institutes and our strategic suppliers to improve barrier circularity.

We are also seeking alternatives to fossil-based barriers, which can be used in our existing equipment and machines utilized across all the different areas of our business.Consumer and regulatory demands are encouraging businesses like DS Smith to target plastic replacement.

The main challenges we face are related to performance and cost. At times, we find that some of the most sustainable barriers are sensitive to water, but irrespective, this means that they can usually provide effective protection against grease and often to gases.

Another key challenge is the scalability of these processes. Often, these new materials are still in the early stages of development, with big-scale production still to come. Also, they are usually more expensive than traditional solutions, so it’s not always possible to apply them in the business.

What are your latest barrier coating solutions and their key benefits?
Aucejo: Most of the solutions we are working on are barrier-led and intended to protect packaging from water and grease. We are also working very actively on barrier technologies to minimize abrasion and protect the product when reducing plastic content, and this also involves trying to avoid laminated papers.

These barriers can be applied using different technologies, and the most commercially available are coating, printing and lamination. We employ these methods selectively, depending on the level of barrier protection required for the targeted application. This approach ensures we can fulfill the specific requirements with the most suitable solution possible, striking the right balance between barrier performance and cost-effectiveness.

The benefits are based on eliminating the laminated plastic layer when possible or reducing the quantity of plastics as much as possible to offer the required solution.

All the barrier developments are thoroughly assessed for food safety compliance when intended for food packaging applications. Additionally, the recyclability of the barrier materials is always evaluated to ensure the packaging solutions align with circular economy principles and can be effectively recycled at the end of their life cycle.

Also, our work on barrier technologies extends to other high-value-added packaging solutions. In this area, we are developing advanced barrier solutions targeting oxygen and aroma barriers.