Abstract: A drum-in-hat disc brake assembly is disclosed having a drum brake shoe with a friction material comprising a phenolic polymer resin having incorporated into the polymer chain one or more inorganic atom-containing groups selected from the group consisting of a boron-containing group, a phosphorous-containing group, a nitrogen-containing group, a silicon-containing group, and a sulfur-containing group.

Abstract: A composition of material for use as a friction material in a brake and its method of manufacture. Liquid double salts of dibasic and monobasic (ammonium-potassium hydrogen) phosphoric acid (DSP) is added to a dry mixture of reinforcing fiber, friction modifiers, fillers and phenolic resin to create a high viscosity slurry. Thereafter, a metallic (magnesium) oxide and para formaldehyde (para) are added to the slurry. Molds which have been previously heated are filled with the slurry and any excess removed. The metallic oxide reacts with the DSP and the para reacts with the phenolic resin to create a two binder matrix for holding the reinforcing fiber, friction material and fillers in a fixed relationship corresponding to the shape of a brake pad. The brake pads are removed from the molds and transported to a ventilated chamber where the internal curing proceeds at or near ambient temperature to complete the manufacture of the brake pad.