ALEXANDRIA, Va., March 17 -- United States Patent no. 12,577,379, issued on March 17, was assigned to NOK Corp. (Tokyo).
"NBR composition and buffer material using the same" was invented by Yuji Miyoshi (Tottori, Japan).
According to the abstract* released by the U.S. Patent & Trademark Office: "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....