Friction member used in vibration wave driving apparatus, and device using the vibration wave driving apparatus as driving source

摘要

A friction member is used in a friction portion in a vibration wave driving apparatus. The friction member comprises a composite resin which comprises polytetrafluoroethylene as a matrix and which further comprises at least an inorganic fiber substance and a heat-resistant resin. A ratio of a content Vf (vol %) of the inorganic fiber substance to a content Vr (vol %) of the heat-resistant resin satisfies the following relation: