| abstract |
The present invention pertains to a thermosetting composition containing: (a1) 2.5 mass% or more of a solid rubber, (a2) less than 5 mass% of a polymer containing olefinic double bonds that is a liquid or paste at 22°C , (a3) 5-20 mass%, as a total with (a2), of a hydrocarbon resin, and (a4) 15 mass% or more of a liquid polydiene, as component (a); and at least one selected from the group consisting of (b1) sulfur and one or more accelerators, (b2) a peroxide vulcanization system or disulfide vulcanization system, and (b3) quinone, quinone dioxime, or dinitrosobenzene, as a vulcanization system (b). |