November 4, 2022
TOKYO – Leading tiremakers are accelerating their development of tires made with plant materials.
Manufacturers are reviewing not only the environmental performance of their automobiles while on the road, but also the raw materials, parts and components used to produce vehicles. Producing environmentally friendly tires is likely to give automakers an edge in the market.
Sumitomo Rubber Industries, Ltd., which sells the Dunlop brand, has been working to manufacture a new synthetic rubber by breeding rubber trees that contain tomato-derived enzymes. As the tomato enzymes have a strength-enhancing effect, this new rubber is expected to reduce the wear of the tires.
A director of the materials planning department at Sumitomo Rubber, said, “As interest in decarbonization is strong, the need [for such products] will increase further.” He said the company aims to put the new product on the market by the 2040s.
Tires for automobiles are generally manufactured with compounds, whereby several kinds of rubber are mixed with such additives as reinforcing agents and coupling agents. Butadiene, one of the main raw materials, is often produced from naphtha, which is related to gasoline.
The Yokohama Rubber Co. has developed a technology for producing butadiene from plants such as sugar cane and used it to make prototype tires. In June, its racing team drove a vehicle equipped with these tires in the U.S. Hill Climb Race, in which automobiles compete on mountain roads, and completed the whole distance. The company has set a target of producing the new product on a commercial basis in 2034.
Stable supply a challenge
Global new car sales have been brisk, with demand for tires also high.
According to Report Ocean, a U.S. market research company, the automobile tire market reached $144.7 billion (about ¥21.55 trillion) in 2021 and is expected to continue growing at a yearly average of 4% from 2022 to 2030.
For global automakers, the environmental impact of manufacturing has been called into question, prompting them to seek more environmentally friendly parts and components.
Natural rubber is used as a raw material for tires. But in Southeast Asia, where more than 90 percent of the main materials are grown, it is feared the resource will be depleted due to logging. In light of this, there are moves to find new plants that could replace existing rubber trees.
The Bridgestone Corp. is looking closely at a shrub called guayule, a plant native to North and Central America. Aiming to put it into commercial use in 2026, the rubber and tire manufacturer has provided racing teams with tires produced on an experimental basis.
An official in charge at Bridgestone said, “We want to make our business sustainable by using diversified natural resources.”
The challenge lies in how to procure it stably and in large quantities. Bridgestone, in collaboration with Kirin Holdings Co., which is researching hops in beer, has begun research on effectively cultivating guayule. As it will take a long time to improve the breed and cultivate it, they are also hurrying to create a system to develop farmland.