RUBBER COMPOSITION FOR TIRE-VULCANIZING BLADDER, AND TIRE-VULCANIZING BLADDER PRODUCED USING SAME

摘要

Conventionally, a bladder having a multi-layer structure has been proposed. However, a lot of effort is required for the production of the bladder, and therefore a bladder having a desired bladder life has not been produced yet. Then, the present invention provides a rubber composition for a tire-vulcanizing bladder, said rubber composition being characterized by containing a rubber component that contains a butyl rubber in an amount of 92 parts by mass or more relative to 100 parts by mass of the rubber component, wherein the butyl rubber is composed of 30 to 100% by mass of a butyl rubber (1) having an unsaturation degree of 0.6 to 1.1% and 0 to 70% by mass of a butyl rubber (2) having an unsaturation degree of 1.5 to 2.0%.