Friction material for transmission

摘要

A friction material for a synchronizer ring comprises (A) a petroleum coke with an ash content of 0.1 mass % to 8 mass % or (B) a pitch coke with an ash content of 0.1 mass % to 8 mass %, more preferably (C) a calcined petroleum coke with an ash content of 0.1 mass % to 1 mass % or (D) a foundry coke with an ash content of 5 mass % to 8 mass %. The friction material is effectively used for a synchronizer ring requiring high coefficient of dynamic friction.