METHOD FOR USING S-(3-AMINOPROPYL)THIOSULFURIC ACID AND/OR METAL SALT THEREOF

摘要

Disclosed is a method for using the S-(3-aminopropyl)thiosulfuric acid and/or metal salt thereof which is to be added to a rubber ingredient that is a raw material for a vulcanized rubber composition. The method is characterized by comprising a pre-kneading step (A) in which a rubber ingredient, a filler, and S-(3-aminopropyl)thiosulfuric acid and/or a metal salt thereof are kneaded, a post-kneading step (B) in which the mixture (A) obtained in the pre-kneading step (A), a sulfur ingredient, and a vulcanization accelerator are kneaded, the accelerator being used in a larger amount by weight than the sulfur ingredient, and a heat treatment step (C) in which the mixture (B) obtained in the post-kneading step (B) is heat-treated to obtain a vulcanized rubber composition. The method is further characterized by imparting durability to the vulcanized rubber composition.