# US 2014/0191477 A1 · Hydrogenated nitrile rubber composition > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0191477 A1 - Document ID: US20140191477A1 - Status: Published application - Kind: A1 - Application number: 14/239,035 - Filed: 2012-08-03 - Published: 2014-07-10 - Earliest claimed: 2011-09-13 - Inventors: Osamu Kobayashi; Hideyuki Murakami - Web page: https://patentgrep.com/patent/US20140191477A1 ## CPC - C08K 3/04: Carbon - C08K 3/013: Fillers, pigments or reinforcing additives - C08K 5/103: with polyalcohols - C08K 5/14: Peroxides - C09K 3/10: {Materials in mouldable or extrudable form} for sealing or packing joints or covers (filling pastes C09D5/34) - F04B 53/16: Casings; Cylinders; Cylinder liners or heads; Fluid connections - F04B 53/164: {Stoffing boxes} - F04D 29/026: {especially adapted for liquid pumps} - F04D 29/126: {especially adapted for liquid pumps} - F16J 15/02: between relatively-stationary surfaces (F16J15/46, F16J15/48 take precedence) - C08K 3/22: of metals - C08K 3/26: Carbonates; Bicarbonates - C08K 3/34: Silicon-containing compounds - C08K 3/346: {Clay} - C08K 3/36: Silica - C08K 2201/019: the composition being defined by the absence of a certain additive - C09K 2200/0612: Butadiene-acrylonitrile rubber - F05C 2225/02: Rubber - F05D 2300/431: Rubber - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) - C09K: MATERIALS FOR MISCELLANEOUS APPLICATIONS, NOT PROVIDED FOR ELSEWHERE - F04B: POSITIVE-DISPLACEMENT MACHINES FOR LIQUIDS; PUMPS (machines for liquids, or pumps, of rotary-piston or oscillating-piston type F04C; non-positive-displacement pumps F04D; pumping of fluid by direct contact of another fluid or by using inertia of fluid to be pumped F04F) - F04D: NON-POSITIVE-DISPLACEMENT PUMPS (engine fuel-injection pumps F02M; ion pumps H01J41/12; electrodynamic pumps H02K44/02) - F16J: PISTONS {(specially adapted for dampers F16F9/32)}; CYLINDERS; SEALINGS - F05C: INDEXING SCHEME RELATING TO MATERIALS, MATERIAL PROPERTIES OR MATERIAL CHARACTERISTICS FOR MACHINES, ENGINES OR PUMPS OTHER THAN NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES - F05D: INDEXING SCHEME FOR ASPECTS RELATING TO NON-POSITIVE-DISPLACEMENT MACHINES OR ENGINES, GAS-TURBINES OR JET-PROPULSION PLANTS ## Abstract Disclosed is a hydrogenated nitrile rubber composition comprising 100 parts by weight of hydrogenated nitrile rubber having a bound acrylonitrile content of 31 to 50% and an iodine value of 30 mg/100 mg or less, 30 to 300 parts by weight of carbon black having a particle size of 61 nm or more and/or other filler, 0.5 to 30 parts by weight of a polyfunctional unsaturated compound cocrosslinking agent, and 1 to 10 parts by weight of an organic peroxide. The hydrogenated nitrile rubber composition has excellent roll processability and can be suitably used as a vulcanization-molding material for a cup gasket or bellows having excellent LLC resistance used in a water pump mechanical seal. ## Claims ### Claim 1 A hydrogenated nitrile rubber composition used as a vulcanization-molding material for a cup gasket or bellows of a water pump mechanical seal, the composition comprising: 100 parts by weight of hydrogenated nitrile rubber having a bound acrylonitrile content of 31 to 50% and an iodine value of 30 mg/100 mg or less; 30 to 300 parts by weight of carbon black having a particle size, as measured according to ASTM D1765, of 61 nm or more and/or other filler; 0.5 to 30 parts by weight of a polyfunctional unsaturated compound co-crosslinking agent; and 1 to 10 parts by weight of an organic peroxide. ### Claim 2 (depends on 1) The hydrogenated nitrile rubber composition according to claim 1, which is free of a plasticizer. ### Claim 3 (depends on 1) The hydrogenated nitrile rubber composition according to claim 1, which provides a static sealing material having a durometer A hardness of less than 70. ### Claim 4 (depends on 1) The hydrogenated nitrile rubber composition according to claim 1, wherein the other filler is at least one member selected from silica, graphite, clay, talc, coke, calcium carbonate, alumina, silicon carbide, and titanium oxide. ### Claim 5 (depends on 4) The hydrogenated nitrile rubber composition according to claim 4, wherein silica is used in combination with 8 parts by weight or less of a coupling agent. ### Claim 6 (depends on 1) The hydrogenated nitrile rubber composition according to claim 1, wherein the polyfunctional unsaturated compound cocrosslinking agent is a difunctional or trifunctional (meth)acrylate. ### Claim 7 (depends on 1) The hydrogenated nitrile rubber composition according to claim 1, wherein the polyfunctional unsaturated compound cocrosslinking agent is used in an amount of 1 to 10 parts by weight. ### Claim 8 (depends on 1) A cup gasket or bellows of a water pump mechanical seal, wherein the cup gasket or bellows is vulcanization-molded from the hydrogenated nitrile rubber composition according to claim 1. ### Claim 9 (depends on 2) The hydrogenated nitrile rubber composition according to claim 2, which provides a static sealing material having a durometer A hardness of less than 70. ### Claim 10 (depends on 2) The hydrogenated nitrile rubber composition according to claim 2, wherein the other filler is at least one member selected from silica, graphite, clay, talc, coke, calcium carbonate, alumina, silicon carbide, and titanium oxide. ### Claim 11 (depends on 10) The hydrogenated nitrile rubber composition according to claim 10, wherein silica is used in combination with 8 parts by weight or less of a coupling agent. ### Claim 12 (depends on 6) The hydrogenated nitrile rubber composition according to claim 6, wherein the polyfunctional unsaturated compound cocrosslinking agent is used in an amount of 1 to 10 parts by weight. ### Claim 13 (depends on 2) A cup gasket or bellows of a water pump mechanical seal, wherein the cup gasket or bellows is vulcanization-molded from the hydrogenated nitrile rubber composition according to claim 2.