Friction facing with porous sheet base

Abstract

Porous friction facing materials containing cellulose fibers are coated with an impregnant of ethyl silicate to provide automatic transmission clutch plate and band linings of improved frictional properties, durability, wear and heat resistance, without use of asbestos. A sheet of paper-like fibrous material may be first impregnated with a phenolic resin binder which is cured to form a first coating and then impregnated with a hydrolyzed solution of ethyl silicate in a solvent. The material is further heated to drive off the solvent and cure the ethyl silicate to form a second outer coating having a higher coefficient of friction than the first coating. The silicate impregnated lining is then bonded to the steel plate or band. Alternatively, the resin impregnated lining material may be first bonded to the metal plate and then the entire plate assembly is impregnated with the ethyl silicate solution and cured.

Dependencies are inferred from the claim text.