# US 2014/0155524 A1 · Rubber composition and pneumatic tire > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2014/0155524 A1 - Document ID: US20140155524A1 - Status: Published application - Kind: A1 - Application number: 13/879,434 - Filed: 2011-09-26 - Published: 2014-06-05 - Earliest claimed: 2010-10-15 - Assignees: The Yokohama Rubber Co., Ltd. - Inventors: Katsunori Shimizu; Satoshi Mihara - Web page: https://patentgrep.com/patent/US20140155524A1 ## CPC - C08K 5/3417: condensed with carbocyclic rings - B60C 1/0016: {Compositions of the tread} - B60C 1/0025: {Compositions of the sidewalls} - C08K 3/36: Silica - C08K 5/34: Heterocyclic compounds having nitrogen in the ring - C08K 5/3447: condensed with carbocyclic rings - C08K 5/3475: condensed with carbocyclic rings - C08K 5/548: containing sulfur {(C08K5/5477 takes precedence)} - C08L 21/00: Compositions of unspecified rubbers - Y02T 10/86: Optimisation of rolling resistance, e.g. weight reduction - C08K: Use of inorganic or non-macromolecular organic substances as compounding ingredients (paints, inks, varnishes, dyes, polishes, adhesives C09) - B60C: VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES - C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06) - Y02T: CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO TRANSPORTATION ## Abstract A rubber composition contains diene-based rubber, silica, a sulfur-containing silane coupling agent, and an amine compound. The amine compound is indole, indigo, and derivatives thereof each of which is represented by a predetermined formula. The content of the silica is 20 to 120 parts by mass based on 100 parts by mass of the diene-based rubber. The content of the sulfur-containing silane coupling agent is 3 to 15 parts by mass based on 100 parts by mass of the silica. The content of the amine compound is 0.5 to 20 parts by mass based on 100 parts by mass of the silica. By the use of the rubber composition with this composition, a tire having improved dispersibility of silica, excellent wet performance, and excellent rolling resistance and showing a suppressed decrease in reinforcing property can be produced. ## Claims ### Claim at position 1 1-5. (canceled) ### Claim 6 A rubber composition comprising diene-based rubber, silica a sulfur-containing silane coupling agent and an amine compound, wherein the amine compound is a compound represented by the following formula (I) and/or the following formula (II); the content of the silica is 20 to 120 parts by mass based on 100 parts by mass of the diene-based rubber; the content of the sulfur-containing silane coupling agent is 3 to 15 parts by mass based on 100 parts by mass of the silica; and the content of the amine compound is 0.5 to 20 parts by mass based on 100 parts by mass of the silica: (wherein X1 and X2 each independently represents a carbon atom or a nitrogen atom, R1 to R3 each independently represents a hydrogen atom, an alkyl group, an alkoxycarbonyl group or a phenyl group which may have a substituent, R4 to R7 each independently represents a hydrogen atom, a fluorine atom, a chlorine atom, an alkyl group, or an alkoxy group, provided that, when X1 is a nitrogen atom, R2 is absent; when X2 is a nitrogen atom, R3 is absent.). ### Claim 7 (depends on 6) The rubber composition according to claim 6, wherein the diene-based rubber is at least one selected from the group consisting of natural rubber (NR), isoprene rubber (IR), styrene-butadiene rubber (SBR), butadiene rubber (BR), chloroprene rubber (CR), acrylonitrile butadiene rubber (NBR), ethylene-propylene-diene copolymer rubber (EPDM), styrene-isoprene rubber, isoprene-butadiene rubber, nitrile rubber, and hydrogenated nitrile rubber. ### Claim 8 (depends on 6) The rubber composition according to claim 6, wherein the silica is at least one selected from the group consisting of fumed silica, fired silica, precipitated silica, crushed silica, molten silica, and colloidal silica. ### Claim 9 (depends on 6) The rubber composition according to claim 6, wherein the content of the silica is 40 to 100 parts by mass. ### Claim 10 (depends on 6) The rubber composition according to claim 6, wherein the content of the sulfur-containing silane coupling agent is 5 to 10 parts by mass. ### Claim 11 (depends on 6) The rubber composition according to claim 6, wherein the content of the amine compound is more preferably 0.5 to 10 parts by mass. ### Claim 12 (depends on 6) The rubber composition according to claim 6, wherein the sulfur-containing silane coupling agent is at least one selected from the group consisting of 3-trimethoxysilylpropyl-N, N-dimethylthiocarbamoyl-tetrasulfide, trimethoxysilylpropyl-mercaptobenzothiazoletetrasulfide, triethoxysilylpropyl-methacrylate-monosulfide, dimethoxymethylsilylpropyl-N,N-dimethylthiocarbamoyl-tetrasulfide, bis-[3-(triethoxysilyl)-propyl]tetrasulfide, bis-[3-(trimethoxysilyl)-propyl]tetrasulfide, bis-[3-(triethoxysilyl)-propyl]disulfide, 3-mercaptopropyl-trimethoxysilane, and 3-mercaptopropyl-triethoxysilane. ### Claim 13 (depends on 6) The rubber composition according to claim 6, wherein the alkyl group is a methyl group. ### Claim 14 (depends on 6) The rubber composition according to claim 6, wherein the alkoxy group is a methoxy group. ### Claim 15 (depends on 6) The rubber composition according to claim 6, wherein the compound represented by the above formula (I) is a compound represented by any of the following formulae (I-a) to (I-d): ### Claim 16 (depends on 6) The rubber composition according to claim 6, wherein the compound represented by the above formula (II) is a compound represented by the following formula (II-a): ### Claim 17 (depends on 6) The rubber composition according to claim 6, further comprising an additional filler other than silica. ### Claim 18 (depends on 6) The rubber composition according to claim 6, wherein the filer is carbon black. ### Claim 19 (depends on 6) The rubber composition according to claim 6, wherein a coupling reaction occurs between the silica and the silane coupling agent, and the amine compound is contained before the coupling reaction. ### Claim 20 (depends on 6) A pneumatic tire comprising the rubber composition according to claim 6. ### Claim 21 (depends on 6) A pneumatic tire comprising the rubber composition according to claim 6 in at least a tire tread.