SGL Carbon manufactures natural fiber prepregs for motorsports

Toyota Hilux. Source | SGL Carbon

In early July 2025, Tras Ltd. (Mishima City), a Japan-based composites company, unveiled a natural fiber body for the Toyota Hilux, which will compete in the Asia Cross Country Rally in Thailand from August 8-16. SGL Carbon (Wiesbaden, Germany), supplied the flax fiber prepreg materials for the car’s body.

SGL Carbon says it has been involved in developing prepregs and components made from natural fibers, such as flax, for several years. The ampliTex natural fiber fabric is manufactured by Bcomp (Fribourg, Switzerland) — with which SGL has collaborated on various projects for some time — followed by pre-impregnation at SGL’s site in Willich, Germany.

“A major challenge was the comparatively high moisture absorption of the flax fibers,” explains Dr. Thomas Meinhardt, team lead technical marketing prepregs at SGL Carbon. “We therefore used a special transparent, fast-curing resin system that has proven particularly resistant to, and is tolerant of, the high moisture content of natural fibers. This ensures an attractive component appearance, as well as good mechanical and thermal properties of the composite material, [all of] which are particularly important in motorsports.”

The finished prepregs were then processed into the final components by Tras. The company specializes in manufacturing, testing and demonstrating car bodies made from natural fibers. “The use of the [SGL’s] resin system was an important improvement for us, as we often face very high humidity in Asia, yet the components must still meet the rigorous demands of racing. With this natural car body, we now have a lightweight, sustainable component that looks great, too,” says Masanao Nitta, CEO of Tras Ltd.

Components made from Bcomp's flax fiber technologies offer up to 85% lower CO2 footprint from cradle to gate compared to pure carbon fiber parts, thanks to the use of renewable raw materials and the possibility of end-of-life thermal energy recovery.

Additionally, every gram of weight counts, especially in motorsports. In combination with Bcomp’s powerRibs reinforcement grid, similar stiffness and weight as virgin carbon fiber components can be achieved. Furthermore, the natural fiber components perform well in crash tests and provide very good vibration damping, making them useful for demanding motorsport applications.

Toyota subsidiary Toyota Customizing & Development (TCD) and its brands TRD and Modellista, which specialize in converting vehicles into sports and special models, also expressed considerable interest in the project. Due to the high quality of the product, natural fibers may be used in future developments.