On February 14, 2008, Sumitomo Rubber Industries held a meeting to highlight its recent technological development work. According to a piece in Tech-On on the meeting, Sumitomo President Tetsuji Mino highlighted three recent developments: a tire made almost entirely of natural (i.e., non-petroleum) materials; a tire featuring a 50% reduction in rolling resistance; and run-flat tires.
Sumitomo subsidiary Dunlop Falken Tyre Ltd. plans to introduce a new generation “eco-tire” on March 1, 2008 under the Enasave 97 tradename. According to Sumitomo’s press release on the new tires, only 3% by weight of the tire’s raw materials are based on petroleum — the antioxidant and the vulcanization accelerators. Using ENR (Evolutional Natural Rubber) technology, Sumitomo successfully substituted natural rubber for synthetic rubber throughout the tire, including sidewalls, innerliner and tread. The tire uses silica as the filler instead of carbon black, and vegetable oils instead of petroleum-based processing oils.
In addition to being 97% petroleum-free, the new tires reduce rolling resistance by 35% compared to Digityre ECO EC201. Sumitomo accomplished this reduction through the use of a unique leaf-shaped tread pattern and specially conditioned natural rubber in the tread compound. Sumitomo has committed to introduce a tire using 100% non-petroleum materials, even if it takes “five to ten years.” According to Sumitomo, an average passenger tire (195/65R15) typically includes about 44% natural materials, mainly natural rubber and oils. In March 2006, Sumitomo introduced the ENASAVE ES801, which was touted as being 70% petroleum-free.
Sizes and suggested retail prices for the Enasave 97 tires are as follows: * 185/65R15 88H ¥15,960 * 195/65R15 91H ¥17,850 * 205/65R15 94H ¥20,160 * 195/55R16 86V ¥22,575
Sumitomo also announced plans to introduce a tire with a 50% reduction in rolling resistance, which would improve fuel efficiency by 10%. The timeline for commercialization of this tires has not yet been determined.
Finally, Sumitomo announced it would ship 100,000 run-flat tires to Japanese automakers in 2008, including Toyota, Honda (for Acura), and Nissan. Sumitomo’s total shipments of run-flats in 2008 are expected to total 1 million, with most sales to BMW. Sumitomo sells run-flats under the Dunlop brand.