Siping (rubber) wear and extends the life of the tire. Both Bridgestone and Michelin sell snow tires that are siped at the factory, while Saf-Tee Siping and Grooving sells machines that can sipe most standard vehicle tires. Siping can also be done by hand. Siping tires may void the manufacturer's warranty. Claims that extended life is achieved by siping may only apply to certain environments, operating temperatures, and rubber compound builds. Siped soles are a characteristic feature of boat shoes. Siping (rubber) Siping is a process of cutting thin slits across a rubber surface to improve traction in wet or icy conditions.
Sumitomo Rubber Industries businesses, which were separately owned, but in 1986 Sumitomo also acquired the Dunlop Tire Corporation of the US from its management. In 1997, Sumitomo formed a joint venture with Goodyear Tire and Rubber Company, by which Goodyear and Sumitomo agreed to manufacture tires for each other's markets, including Dunlop branded tires. As part of the agreement, Goodyear acquired 75% interests in Dunlop Tyres, the UK company which Sumitomo had formed, and in Dunlop Tire Corporation. Goodyear and Sumitomo also made investments in each other. On 14 February 2014, Goodyear announced its intention to dissolve its partnership with Sumitomo due to