Patent ID: 7972675

Claim:
A friction material comprising: a fibrous body as a base of the friction material; a resin contained in the fibrous body; a front surface defined by an exposed surface of the fibrous body and used as a frictional surface for frictional engagement with a counterpart member; and a rear surface located opposite to the front surface; wherein the fibrous body is made of fibers and a filler, and the resin is contained in the fibrous body so as to make a paper friction material as the friction material, wherein a resin amount per unit volume in a thickness direction from a side of the front surface to a side of the rear surface of the friction material is set such that a resin amount per unit volume of a front portion beginning at the front surface and extending in the thickness direction to a predetermined depth in the thickness direction is lower than a resin amount per unit volume of a portion located away from the front portion in the thickness direction and having a highest resin amount per unit volume in the thickness direction, wherein the distribution of the resin amount per unit volume of the friction material changes in a continuous manner in the thickness direction of the friction material from the front surface to the rear surface, wherein an average resin amount per unit volume within a range having a depth of about 40% from the front surface in the thickness direction of the friction material is made lower than the average resin amount per unit volume of the entire friction material, wherein the distribution of the resin amount per unit volume in the thickness direction is highest at a portion near the rear surface and continuously decreases as it goes towards an inside in the thickness direction of the friction material so as to be lowest at the front portion, and wherein the front portion is provided with from the front surface to a depth of about 10% in the thickness direction of the friction material.