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Product | Technology | Patents

Reselo – Replacing Synthetic Rubber with Bark

Every year, more than 15 million tonnes of fossil-based rubber are produced worldwide, resulting in products such as car tyres, hairbands, hoses, and shoe soles. Rubber production leads to significant carbon dioxide emissions – and many companies are seeking greener alternatives.

Reselo, a spin-off from KTH, is developing a bio-rubber entirely based on bark, a by-product of the forestry industry. The aim is to replace fossil-based rubber, which is used in a wide range of products and contributes to large carbon dioxide emissions.

Porträttbild på man i svart skjorta vid namnThomas Baumgarten
Thomas Baumgarten

The background to Reselo was a research project at KTH funded by the Wallenberg Wood Science Center. The project aimed to further explore the use of components from birch bark and modify them using enzymes to generate new materials. “In the process of isolating suberin molecules from birch bark, I realised that it should be possible to generate a material directly from suberin. Surprisingly, the material I created had elastomeric properties, meaning the material could be stretched under strong resistance and then quickly contract and fully return to its original shape. The material also had interesting properties such as high flexibility and water resistance,” says Thomas Baumgarten, co-founder and Chief Technology Officer at Reselo.

It was far from certain that a company would emerge from these discoveries.

– As a researcher, my first thought was not to start a company, but I had seen some examples of successful spin-outs from the lab at Stockholm University where I completed my PhD. And having a renewable, fossil-free material that looked like it could be produced on an industrial scale motivated me to consider commercialising the technology.

Substantial Support from KTH Innovation

Reselo received significant support from KTH Innovation right from the start, and the company was founded in 2020.

– KTH Innovation has been a great support — not least in the work of identifying and securing our intellectual property rights. As a startup, resources are limited and their help was therefore greatly appreciated.

An interesting detail about Reselo's biogum is that it can be adapted to different rubber qualities, cured like today's rubber, manufactured using existing equipment - and thus replace existing fossil-based rubber completely.

Reselo's innovation has led to a series of collaborations with various companies. One such example is the shoe manufacturer Skråmträsk sko, for which Reselo is developing an outsole. Through winning Finnish tyre manufacturer Nokian Tyres' innovation competition Fast Race, Big Change 2023, Reselo has gained an opportunity to explore the conditions for future collaboration within the largest segment of the rubber market. Reselo is also part of the innovation hub Mobility Xlab, where automotive companies such as Volvo Cars, Polestar, and AB Volvo collaborate with startup companies. There, they are exploring other possible applications in vehicle interiors - aside from car tyres.

More Patents in Sight

The company has both a registered EU trademark in the form of the name Reselo and a patent that was approved by the PRV in December 2023. In addition to this, they have also filed a PCT application.

– For a startup, patents are especially important in dealings with potential investors. It shows that you are making progress and that your technology has clear value. The search reports from PRV and from the IPO have also been very valuable. There we see the novelty in what we submit and strengthen our argument — not least towards investors.

Thomas Baumgarten sees more applications and more potential patents for Reselo in the future. But that will happen in due time.

Focus on Creating Products and Scaling Up Operations

– The focus right now is on implementing our material into customer products. This is happening through an iterative process. Concurrently, we are looking at how we can scale up our operations, including planning and building a first demonstration factory. The next step is to look at international expansion,Thomas Baumgarten concludes.

The interview was made in 2024. Photo: Lisa Johnson/Pixabay