Patent ID: 7309725

Claim:
A fibrous base material to be subjected, together with a thermosetting resin as a binder, to the preparation of wet frictional materials, wherein the fibrous base material does not comprise organic synthetic soluble polymer particles, wherein the fibrous base material comprises a fiber component, a friction adjusting material and a filler, wherein the fiber component comprises 5 to 50% by weight of a homoacrylonitrile fiber and/or a homoacrylonitrile fiber in a pulp form, wherein a modulus of elasticity of the homoacrylonitrile fiber at 180° C. is not less than 10 cN/dtex, and a shrinking rate at 200° C. is 0 to 5%, and wherein the homoacrylonitrile fiber in a pulp form is prepared by fibrillation of said homoacrylonitrile fiber.