NBR composition and buffer material using the same

Abstract

An NBR composition, that is excellent in rubber material processability and vulcanized rubber hardness, comprising 93 to 105 parts by weight of carbon black with a carbon black grade of N330 or N550, 1.0 to 4.0 parts by weight of a vulcanization retarder, 2.0 to 5.0 parts by weight of thiazole-based and thiuram-based vulcanization accelerators, and 1.0 to 4.0 parts by weight of a sulfur-based vulcanizing agent, based on 100 parts by weight of NBR. The vulcanized molded product obtained from the NBR composition has a rubber hardness (Duro A, instant) of 85 or more according to JIS K6253 corresponding to ISO 18517, and can be effectively used as an automobile buffer material such as a stopper for electric power steering, a buffer material for nailers, a buffer material for devices equipped with hydraulic cylinders, or the like.

Dependencies are inferred from the claim text.