Friction material with friction modifying layer having symmetrical geometric shapes

摘要

A friction material has a first layer of a base material and a second layer of at least one type of friction modifying particle having substantially symmetrical geometric shapes on a top surface of the base material. The second layer has an average thickness of about 30 to about 200 microns and the surface area coverage of about 80 to about 100% such that the top layer has a fluid permeability lower than the first layer.