Patent ID: 8563448

Claim:
A friction material comprising: a resin; and a fibrous base material impregnated with the resin and having a single ply, the fibrous base material including; a plurality of aramid fibers present in a first amount and including; a first component including a plurality of fibrillated aramid fibers; and a second component including a plurality of non-fibrillated aramid fibers; wherein the first component and the second component are present in the fibrous base material in a ratio of about 2:1; a plurality of polyacrylonitrile-based carbon fibers present in a second amount that is less than the first amount and including; a third component having a third average length, wherein the third component is further defined as a plurality of milled polyacrylonitrile-based carbon fibers and the third average length is less than about 500 microns; and a fourth component having a fourth average length that is longer than the third average length; wherein the third component and the fourth component are present in the fibrous base material in a ratio of about 1:1; a plurality of carbon particles present in a third amount that is less than or equal to the second amount; a plurality of mineral fibers present in a fourth amount that is less than or equal to the second amount; and diatomaceous earth present in a fifth amount that is greater than the first amount, wherein the fifth amount is from about 40 parts by weight to about 47 parts by weight based on 100 parts by weight of the fibrous base material.