# US 2014/0194552 A1 · Rubber composition for tires, 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 2014/0194552 A1 - Document ID: US20140194552A1 - Status: Published application - Kind: A1 - Application number: 14/343,342 - Filed: 2012-10-16 - Published: 2014-07-10 - Earliest claimed: 2011-10-17 - Assignees: Sumitomo Rubber Industries, Ltd. - Applicants: Sumitomo Rubber Industries, Ltd - Inventors: Soh Ishino - Web page: https://patentgrep.com/patent/US20140194552A1 ## CPC - C08L 9/06: Copolymers with styrene - B60C 1/0016: {Compositions of the tread} - C08C 19/22: Incorporating nitrogen atoms into the molecule - C08C 19/44: of polymers containing metal atoms exclusively at one or both ends of the skeleton - C08L 15/00: Compositions of rubber derivatives (C08L11/00, C08L13/00 take precedence) - C08L 2312/00: Crosslinking - C08L: COMPOSITIONS OF MACROMOLECULAR COMPOUNDS (compositions based on polymerisable monomers C08F, C08G; artificial filaments or fibres D01F; textile treating compositions D06) - B60C: VEHICLE TYRES; TYRE INFLATION; TYRE CHANGING; CONNECTING VALVES TO INFLATABLE ELASTIC BODIES IN GENERAL; DEVICES OR ARRANGEMENTS RELATED TO TYRES - C08C: TREATMENT OR CHEMICAL MODIFICATION OF RUBBERS ## Abstract Provided are: a rubber composition for tires capable of improving fuel economy, wet grip performance, and abrasion resistance; and a pneumatic tire including the same. Included is a rubber composition for tires including: a diene polymer; silica; and a liquid resin having a softening point of −20 to 20° C., the diene polymer being a modified diene polymer obtained by reacting components (A) and (B), the liquid resin being present in an amount of 3-40 parts by mass per 100 parts by mass of the rubber component, the component (A) being an active alkali metal-terminated conjugated diene polymer obtained by polymerizing a conjugated diene monomer alone or with an aromatic vinyl monomer, in the presence of a component (C) the component (B) being a modifier containing a functional group, the component (C) being a chemical species obtained by reacting an organic alkali metal compound and a compound of Formula (1) below. ## Claims ### Claim 1 A rubber composition for tires, comprising: a diene polymer; silica; and a liquid resin having a softening point of −20° C. to 20° C., the diene polymer being a modified diene polymer obtained by reacting a component (A) and a component (B), the liquid resin being present in an amount of 3 to 40 parts by mass per 100 parts by mass of a rubber component of the rubber composition, the component (A) being an active alkali metal-terminated conjugated diene polymer obtained by polymerizing a conjugated diene monomer alone or with an aromatic vinyl monomer, in the presence of a component (C), the component (B) being a modifier containing a functional group, and the component (C) being a chemical species obtained by reacting an organic alkali metal compound and a compound represented by the following Formula (1): wherein R1 and R2 are the same as or different from each other, each representing a hydrogen atom, a branched or unbranched alkyl group, a branched or unbranched aryl group, a branched or unbranched alkoxy group, a branched or unbranched silyloxy group, a branched or unbranched acetal group, a carboxyl group, a mercapto group, or a derivative thereof; and A represents a branched or unbranched alkylene group, a branched or unbranched arylene group, or a derivative thereof. ### Claim 2 (depends on 1) The rubber composition for tires according to claim 1, wherein the compound represented by Formula (1) is a compound represented by the following Formula (2): ### Claim 3 (depends on 1) The rubber composition for tires according to claim 1, wherein the modifier is a compound represented by the following Formula (3): wherein R3 and R4 are the same as or different from each other, each representing a C1 to C10 hydrocarbon group which may contain at least one group selected from the group consisting of ether and tertiary amine groups; R5 and R6 are the same as or different from each other, each representing a hydrogen atom or a C1 to C20 hydrocarbon group which may contain at least one group selected from the group consisting of ether and tertiary amine groups; R7 represents a C 1 to C20 hydrocarbon group which may contain at least one group selected from the group consisting of ether, tertiary amine, epoxy, carbonyl, and halogen groups; and n represents an integer of 1 to 6. ### Claim 4 (depends on 1) The rubber composition for tires according to claim 1, wherein the same modifier is introduced into both chain ends of the active conjugated diene polymer. ### Claim 5 (depends on 1) The rubber composition for tires according to claims 1, wherein the rubber component contains 5% by mass or more of the diene polymer based on 100% by mass of the rubber component. ### Claim 6 (depends on 1) The rubber composition for tires according to claim 1, wherein the conjugated diene monomer is at least one of 1,3-butadiene and isoprene, and the aromatic vinyl monomer is styrene. ### Claim 7 (depends on 1) The rubber composition for tires according to claim 1, wherein the modified diene polymer is a modified styrene butadiene rubber obtained by polymerizing 1,3-butadiene and styrene. ### Claim 8 (depends on 1) The rubber composition for tires according to claim 1, wherein the liquid resin is at least one selected from the group consisting of liquid coumarone-indene resins, liquid indene resins, and liquid α-methylstyrene resins. ### Claim 9 (depends on 1) The rubber composition for tires according to claim 1, wherein the silica has a nitrogen adsorption specific surface area of 40 to 250 m2/g. ### Claim 10 (depends on 1) The rubber composition for tires according to claim 1, comprising at least one of a silane coupling agent represented by Formula (4) below and a silane coupling agent containing a linking unit A represented by Formula (5) below and a linking unit B represented by Formula (6) below: wherein R8 represents a group represented by —O—(R12—O)m—R13 where m R12s are the same as or different from one another, each representing a branched or unbranched divalent C1 to C30 hydrocarbon group, R13 represents a branched or unbranched C1 to C30 alkyl group, a branched or unbranched C2 to C30 alkenyl group, a C6 to C30 aryl group, or a C7 to C30 aralkyl group, and m represents an integer of 1 to 30; R9 and R10 are the same as or different from each other, each representing a group as defined for R8, a branched or unbranched C1 to C12 alkyl group, or a group represented by —O—R14 where R14 represents a hydrogen atom, a branched or unbranched C1 to C30 alkyl group, a branched or unbranched C2 to C30 alkenyl group, a C6 to C30 aryl group, or a C7 to C30 aralkyl group; and R11 represents a branched or unbranched C1 to C30 alkylene group; wherein R15 represents hydrogen, a halogen, a branched or unbranched C1 to C30 alkyl group, a branched or unbranched C2 to C30 alkenyl group, a branched or unbranched C2 to C30 alkynyl group, or a group obtained by replacing a terminal hydrogen of the alkyl group with a hydroxyl or carboxyl group; and R16 represents a branched or unbranched C 1 to C30 alkylene group, a branched or unbranched C2 to C30 alkenylene group, or a branched or unbranched C2 to C30 alkynylene group, provided that R15 and R16 together may form a ring. ### Claim 11 (depends on 1) The rubber composition for tires according to claim 1, comprising a vulcanization accelerator represented by the following Formula (7): (C6H5—CH2)zN—(C═S)—S-(C═S)—N(CH2—C6H5)2 (7) wherein z represents an integer of 1 to 8. ### Claim 12 (depends on 1) The rubber composition for tires according to claim 1, which is intended to be used as a rubber composition for treads. ### Claim 13 (depends on 1) A pneumatic tire, comprising the rubber composition according to claim 1. ### Claim 14 (depends on 2) The rubber composition for tires according to claim 2, wherein the modifier is a compound represented by the following Formula (3): wherein R3 and R4 are the same as or different from each other, each representing a C1 to C10 hydrocarbon group which may contain at least one group selected from the group consisting of ether and tertiary amine groups; R5 and R6 are the same as or different from each other, each representing a hydrogen atom or a C1 to C20 hydrocarbon group which may contain at least one group selected from the group consisting of ether and tertiary amine groups; R7 represents a C1 to C20 hydrocarbon group which may contain at least one group selected from the group consisting of ether, tertiary amine, epoxy, carbonyl, and halogen groups; and n represents an integer of 1 to 6. ### Claim 15 (depends on 2) The rubber composition for tires according to claim 2, wherein the same modifier is introduced into both chain ends of the active conjugated diene polymer. ### Claim 16 (depends on 3) The rubber composition for tires according to claim 3, wherein the same modifier is introduced into both chain ends of the active conjugated diene polymer. ### Claim 17 (depends on 2) The rubber composition for tires according to claim 2, wherein the rubber component contains 5% by mass or more of the diene polymer based on 100% by mass of the rubber component. ### Claim 18 (depends on 3) The rubber composition for tires according to claim 3, wherein the rubber component contains 5% by mass or more of the diene polymer based on 100% by mass of the rubber component. ### Claim 19 (depends on 4) The rubber composition for tires according to claim 4, wherein the rubber component contains 5% by mass or more of the diene polymer based on 100% by mass of the rubber component. ### Claim 20 (depends on 2) The rubber composition for tires according to claim 2, wherein the conjugated diene monomer is at least one of 1,3-butadiene and isoprene, and the aromatic vinyl monomer is styrene.