Stellantis, the multinational automotive giant, has filed a patent for an innovative and eco-friendly tyre compound that incorporates discarded eggshells. This groundbreaking development aims to replace traditional fillers like carbon black and silica with calcium oxide (CaO) extracted from eggshells, potentially improving both environmental sustainability and tyre performance.
A New Use for Eggshells
The patent, initially submitted in mid-2023 and published by the United States Patent and Trademark Office on January 23, 2024, details Stellantis’ plan to use calcium oxide derived from eggshells as a coupling agent in tyre production. This approach could significantly reduce waste by repurposing bio-waste while also minimising reliance on chemical-based materials.
Hen eggshells, which are over 90% calcium carbonate, can be transformed into calcium oxide through high-temperature processing. According to Stellantis, this innovative material could enhance a tyre’s rolling resistance, improve grip in wet conditions, and increase fuel efficiency by approximately 3%, while reducing rolling resistance by 20% compared to conventional tyres containing carbon black.





