Abstract: A rubber composition includes hydrogenated acrylonitrile-butadiene rubber (HNBR), a copper dithiocarbamate salt compound and sulfur. The use of the copper dithiocarbamate salt compound results in the vulcanized rubber composition exhibiting improved heat resistance as compared to a rubber material that does not include the copper dithiocarbamate salt compound. Toothed belts and V-ribbed belts can be made using the rubber composition to produce belts exhibiting improved heat resistance.

Abstract: A power transmission belt having a belt body with an inside surface and an outside surface, with the belt body having a compression section and a tension section, spaced outside of the compression section. At least a first part of the tension section is defined by a chlorosulfonated polyethylene rubber composition having a chlorine content of 15 to 30% by weight. At least a second part of the compression section is defined by a rubber composition that is different than the rubber composition of the first part.

Abstract: A power transmission belt having improved service life in high and low temperature environments is disclosed. The power transmission belt includes a compressed rubber layer of a low density chlorosulfonated polyethylene having a straight-chain molecular structure which is formed so that the chlorine content is within the range of about 15 to about 35% by weight. The chlorosulfonated polyethylene can have a sulfur content in the range of about 0.5 to about 2.5% by weight. A magnesium oxide-aluminum oxide solid solution can be admixed with the chlorosulfonated polyethylene. The power transmission belt can also include an adhesion rubber layer made of a chloroprene rubber composition or a hydrogenated acrylonitrile-butadiene rubber composition with at least one tension member at least partially embedded therein.

Abstract: A power transmission belt having a length and a lateral extent. The belt consists of a tension layer and a compression layer with the compression layer defined at least partially by acrylonitrile-butadiene copolymer rubber (hydrogenated nitrile rubber), having at least an 80% hydrogen addition rate, and a plurality of substantially laterally oriented fibers in the acrylonitrile-butadiene copolymer rubber in the compression layer. The fibers are treated with one of resorcin-formalin-nitrile rubber latex (RFL) and resorcin-formalin-hydrogenated nitrile rubber latex (RFL) having at least an 80% hydrogen addition rate.

Abstract: An aramid fiber cord for use as a component in a power transmission belt, which aramid fiber cord has a plurality of aramid fiber filaments of 300 to 3100 denier adhesively treated and formed into a strand with a primary twist factor (Y) in a range of -1 to 1. A plurality of the strands are formed into the cord with a finishing twist factor (X) in a range of 1 to 4. The primary twist factor (Y) and finishing twist factor (X) satisfy the following equations: Y is .gtoreq. to -0.6X+1.3 and Y is .gtoreq. to -1.5x+5.0.

Abstract: The present invention is directed to a method wherein fibers are treated with a first, second, and third treatment solution. The third treatment solution includes a chlorinated rubber and a rubber-containing composition having acrylonitrile-butadiene rubber or hydrogenated acrylonitrile-butadiene rubber. The treated fibers are positioned contiguous, and adhered, to an unvulcanized hydrogenated acrylonitrile-butadiene rubber composition which is then vulcanized. The resulting rubber-fiber composite exhibits improved adhesion between the hydrogenated acrylonitrile-butadiene rubber composition and the fibers. Adhesion is maintained in a hot environment even if subjected to what would conventionally be considered conditions that would result in thermal deterioration under high temperature. Thus, the rubber-fiber composite exhibits enhanced durability under the severe service conditions experienced by rubber-fiber composites.

Abstract: An improved cord for use in a power transmission belt. Before an adhesive stretching thermal fixation treatment, the cord, upon being heated, has a ratio of shrinkage percentage to shrinkage stress of less than 12% per g/d. After an adhesive stretching thermal fixation treatment, the heated cord has a ratio of shrinkage percentage to shrinkage stress of less than 6% per g/d.

Abstract: A toothed power transmission belt (10) is manufactured by an improved method to have substantially improved resistance to tooth root face cracking. The manufacture utilizes a modified rubber blend forming the teeth (15) and may utilize the same blend for embedding the load-carrying cords (14) to provide improved bonding of the teeth (15) to the cords (14) over a wide range of temperatures.

Abstract: A pressure-responsive variable electrical resistive rubber material including at least one inorganic filler selected from a group consisting of conductive carbon black, short fibers of nonmetallic inorganic material, powder, and whiskers. The filler is dispersed in a matrix formed of an electrically insulative rubber. The rubber material exhibits a gradually reducing resistance value as a gradually increased pressing force is applied thereto. The rubber material provides a wide range of relationship between the applied force and the electrical resistance thereof. The rubber material is adapted for use as a pressure sensor having excellent fatigue creep resistance.

Abstract: A power transmission belt wherein at least a portion thereof is formed as a composite of 1 to 100 parts by weight of whiskers distributed in 100 parts by weight of rubber. The composite may form the compression section of the belt. The composite may be utilized as impregnating rubber for a fabric cover portion of the belt. The whiskers preferably have a diameter in the range of approximate 0.1 micron to 1.0 micron, and a length of approximately 10 microns to 500 microns. In the illustrated embodiment, the whiskers are acicular single crystal whiskers.

Abstract: A power transmission belt having a compression portion. The belt is composed of rubber having disposed therein at least approximately 2 to 100 parts by weight of ceramic powder per 100 parts by weight of rubber. The belt provides remarkably improved wear and adhesive resistance without decreased bending resistance.

Abstract: A power transmission belt manufacture wherein a modified rubber blend is utilized as at least one portion of the belt, with the blend including a silane coupling agent, silica and carbon black. The blend is advantageously adapted for use as the cushion rubber embedding the load-carrying cords of the belt. The invention comprehends the use of the blend further as at least one of the compression and tension sections of the belt, as desired. The modified rubber blend is advantageously utilized in power transmission belts having widely varying configurations and characteristics.