The invention illustrates a material for friction components of disc brakes comprising between 1% and 8% by weight of at least one preceramic resin and between 2% and 10% by weight of at least one organic resin. It also illustrates a friction component for a disc brake, a disc brake, and a process for producing such a material.

A friction material comprising: (a) at least one lubricant, wherein the at least one lubricant includes an amount of graphite, and wherein at least about 30 percent by weight of the graphite has a particle size of greater than about 500 microns using a sieve analysis; (b) at least one metal containing constituent for imparting reinforcement, thermal conductivity, and/or friction when the friction material is brought into contact with a movable member, wherein the at least one metal containing constituent includes iron and an iron containing compound; (c) a micro-particulated material; (d) one or more filler materials; (e) optionally at least one processing aid; (f) a balance being an organic binder, wherein the organic binder has less than 1 percent by weight of free phenol; wherein the friction material is free of asbestos and substantially devoid of copper.

A coating composition for a lubricating coating film includes: (A) a phenolic resin; (B) an epoxy resin having an epoxy equivalent weight of 600 to 4000; and (C) at least one type of solid lubricant. The epoxy equivalent weight is generally defined by the number average molecular weight per the number of epoxy groups in a single molecule. The coating composition has a weight ratio of component (A) to the total weight of component (A) and component (B) of at least 50 weight %. A lubricating coating film, formed from the coating composition, has a high level of flexibility on surfaces of various base materials.

A latex of a carboxyl group-containing nitrile rubber contains an ,-ethylenically unsaturated nitrile monomer unit in a content of 8 to 60 wt % and having an iodine value of 120 or less, wherein the total content of potassium and sodium contained in the latex is 2,300 to 10,000 ppm by weight with respect to the whole latex.

A clutch friction material includes a base material containing a rubber material and a thermosetting resin. The clutch friction material also includes an intermediate layer disposed on the base material. The intermediate layer includes either a glassy carbon structure or a graphite structure formed as a result of thermal curing of the thermosetting resin contained in the base material. In addition, the clutch friction material includes an outermost surface layer disposed on the intermediate layer. The outermost surface layer contains a pyrolysate produced as a result of pyrolysis of rubber and resin components contained in the base material.

According to the present invention, there is provided a resol phenolic resin for a friction material wherein the resol phenolic resin has a structural unit A represented by Formula (1) and a structural unit B represented by Formula (2): ##STR00001##
wherein in Formula (1), m represents an integer of 1 or more; in a case where m is 1, R represents a methylol group; and in a case where m is 2 or more, R's independently represent a hydrogen atom or a methylol group and at least one R is a methylol group; and ##STR00002##
wherein in Formula (2), n represents an integer of 1 or more; in a case where n is 1, R represents a methylol group; and in a case where n is 2 or more, R's independently represent a hydrogen atom or a methylol group and at least one R is a methylol group.

A friction material comprising: (a) at least one lubricant, wherein the at least one lubricant includes an amount of graphite, and wherein at least about 30 percent by weight of the graphite has a particle size of greater than about 500 microns using a sieve analysis; (b) at least one metal containing constituent for imparting reinforcement, thermal conductivity, and/or friction when the friction material is brought into contact with a movable member, wherein the at least one metal containing constituent includes iron and an iron containing compound; (c) a micro-particulated material; (d) one or more filler materials; (e) optionally at least one processing aid; (f) a balance being an organic binder, wherein the organic binder has less than 1 percent by weight of free phenol; wherein the friction material is free of asbestos and substantially devoid of copper.

Provided is a liquid phenolic resol resin containing a partial structure represented by General Formula (P-1) [in the formula, R.sup.1, R.sup.2 and R.sup.3 each independently represent a hydrogen atom or CH.sub.2OH, R.sup.4 represents a linear unsaturated hydrocarbon group having 10 or more carbon atoms, and * represents a bond].

##STR00001##

A railway brake lining includes one or more primary friction members, one or more secondary friction members, and a base plate. Each of the primary friction members is elastically fastened to the base plate. Each of the secondary friction members is fixed on the base plate. A minimum distance between the friction members and a center of an axle is denoted by r1, and a maximum distance between the friction members and the center of the axle is denoted by r2. The centers of one or more of the primary friction members are located in an area that is at a distance of {r1+(r2r1)/3} to {r1+2(r2r1)/3} from the center of the axle. The total slide contact area T1 of the primary friction members and the total slide contact area T2 of the secondary friction members satisfy 2/25T2/(T1+T2).

[OBJECT] To provide a friction material used for a brake shoe of a drum brake utilizing for a passenger car, which continuously reduces generation of low frequency noise and provides excellent braking effectiveness and wear resistance.

[MEANS TO RESOLVE] A friction material used for a brake shoe of a drum brake utilizing for a passenger car, which is manufactured by forming a friction material composition containing a binder, an organic fiber, an inorganic friction modifier, an organic friction modifier, a pH adjuster, and an inorganic filler, where the friction material composition contains no cleavable substance, 8-12 weight %, relative to the total amount of the friction material composition, of a phenolic thermosetting resin as the binder, 9-18 weight %, relative to the total amount of the friction material composition, of cashew dust as the organic friction modifier, 6-12 weight %, relative to the total amount of the friction material composition, of a rubber particle, where the total amount of the cashew dust and rubber particle is 18-25 weight % relative to the total amount of the friction material composition, and 4-10 weight %, relative to the total amount of the friction material composition, of the aluminum particle as the inorganic friction modifier. The friction material contains the phenolic thermosetting resin consists of a straight novolak phenolic resin alone and the friction material composition contains the unvulcanized nitrile rubber (NBR) particle as a part of the rubber particle or an entire rubber particle.