Abstract: A method of coating disc brake pads to obscure and seal minor surface imperfections, thereby reducing scrap rates. A preform of friction lining material is coated prior to molding and curing the preform and bonding the same to the backing plate to form the brake pad assembly. The preform is coated with an aqueous composition containing a solids mixture of 5–50 vol. % resin and 50–95 vol. % non-resin solids. Advantageously, the coating composition has a 5–30 vol. % solids mixture content, which solids mixture includes 15–25 vol. % resin, 0–10 vol. % powdered elastomer, 5–15 vol. % carbon black, 20–50 vol. % inorganic fillers, 5–15 vol. % organic fibers and 1–10 vol. % inorganic flake material.

Abstract: A method of coating disc brake pads to obscure and seal minor surface imperfections, thereby reducing scrap rates. A preform of friction lining material is coated prior to molding and curing the preform and bonding the same to the backing plate to form the brake pad assembly. The preform is coated with an aqueous composition containing a solids mixture of 5-50 vol. % resin and 50-95 vol. % non-resin solids. Advantageously, the coating composition has a 5-30 vol. % solids mixture content, which solids mixture includes 15-25 vol. % resin, 0-10 vol. % powdered elastomer, 5-15 vol. % carbon black, 20-50 vol. % inorganic fillers, 5-15 vol. % organic fibers and 1-10 vol. % inorganic flake material.

Abstract: A slurry composition and a method for producing a friction material from the slurry composition, wherein long fiber lengths and large particle sizes are incorporated without fracture and without a high content of pulp and other processing aids. The slurry comprises water and 10-50% by weight solids, the solids comprising 2-15 vol. % organic fibers of 2-15 mm length, 2-20 vol. % organic pulp of up to 8 mm length, 2-10 vol. % inorganic fibers of 2-15 mm length, 2-15 vol. % metallic fibers of 2-15 mm length, 2-10 vol. % inorganic flake materials of ½-10 mm in the largest dimension, 5-20 vol. % carbonaceous particles of ½-10 mm in the largest dimension, and resin binder. The slurry is placed in a die cavity, and the water from the slurry is extracted by pressing on the slurry in the die cavity with a die punch sized to form a gap between the punch and the die sidewall.

Abstract: Friction materials for clutch, brake shoes and the like are formed of a paper having reduced or eliminated non-functional processing additives. The paper composition includes components selected from a group consisting of aramid pulp, aramid staple, carbon/polyacrylonitrile fibers, glass wool, potassium octatitanate, bronze wool, high surface area filter cake, graphite, amorphous carbon and cyanated phenolic resin. The paper composition may be pre-compounded to a particle size in the range of 60 to 200 mesh. Part molding may be carried out by microwave heating the paper at 250° to 55° F.

Abstract: Friction materials for clutch plates, brake shoes and the like are formed of a paper having reduced or eliminated non-functional processing additives. The paper composition includes components selected from a group consisting of aramid pulp, aramid staple, carbon/polyacrylonitrile fibers, glass wool, potassium octatitinate, bronze wool, high surface area filter cake, graphite, amorphous carbon and cyanated phenolic resin. The paper composition may be precompounded to a particle size in the range of 60 to 200 mesh. Part molding may be carried out by microwave heating the paper at 250° to 550° F. The precompounded and dispersed resin provides improved bonding of parts to clutch plates or brake shoes and the like.

Abstract: A friction material pad comprises a lamination of stacked sheets, each of which has a top edge forming the friction face that is generally parallel to the direction of relative rotation between the friction pad and an opposing rotary member. Each sheet is formed by a wet paper making process and has a plurality of unwoven fibers, platelets, flakes, or the like, more than half of which are oriented within 45.degree. of perpendicularity to the top edge, the sheets being bound together by a resin binder to form a lamination in which the sheet edges progress from inner to outer sheets to form the friction face of the pad, each sheet having the same blend of friction and lubricating particles, fibers and fillers in a resin matrix. Three groups of sheets are heat aged to different densities and have different friction, hardness and stiffness characteristics.

Abstract: An improved friction material may be made having reinforcing fibers aligned generally perpendicular to the friction surface of said material by forming a paper of fibrous friction materials such that the fibers in the paper are aligned closely to the longitudinal axis of the paper and then folding or cutting the paper into pleats or strips such that the pleats or strips are bonded together with the edges defining the friction surface of the friction body and the fibers perpendicular to that surface.

Abstract: An improved friction material composite is disclosed that contains a fibrous reinforcing constituent, various friction imparting and controlling additives, and a thermosetting resin mixture in which mixture is contained pitch, a polyimide resin, and optionally a phenolic resin. Pitch-polyimide mixtures can be formulated to provide unusually high temperature resistance and strength and the pitch-polyimide-phenolic resin mixtures formulated to provide like properties at moderate cost.