PNEUMATIC TIRE

• US 20140246136A1
• Filed: 07/27/2012
• Published: 09/04/2014
• Est. Priority Date: 11/09/2011
• Status: Active Grant

• Current Assignee: Sumitomo Rubber Industries Limited
• Original Assignee: Sumitomo Rubber Industries Limited
• Inventors: Iizuka, Toru, Masui, Tomomi, Sugimoto, Mutsuki
• Granted Patent: US 9,902,199 B2
• Time in Patent Office: Days
• US Class Current: 152/510
• CPC Class Codes: B32B 2270/00 Resin or rubber layer containing a blend of at least two different polymers
• CPC Class Codes: B32B 2274/00 Thermoplastic elastomer material thermoplastic elastomer fibres B32B2262/0215, thermoplastic elastomer particles B32B2264/0221, thermoplastic elastomer foam B32B2266/0292
• CPC Class Codes: B32B 2307/54 Yield strength; Tensile strength
• CPC Class Codes: B32B 2307/71 Resistive to light or to UV
• CPC Class Codes: B32B 2307/712 Weather resistant
• CPC Class Codes: B32B 2307/718 Weight, e.g. weight per square meter
• CPC Class Codes: B32B 2307/724 Permeability to gases, adsorption
• CPC Class Codes: B32B 25/08 of synthetic resin
• CPC Class Codes: B32B 25/18 comprising butyl or halobutyl rubber
• CPC Class Codes: B32B 2605/00 Vehicles
• CPC Class Codes: B32B 27/08 of synthetic resin
• CPC Class Codes: B32B 27/302 comprising aromatic vinyl (co)polymers, e.g. styrenic (co)polymers
• CPC Class Codes: B60C 1/0008 Compositions of the inner liner
• CPC Class Codes: B60C 2005/145 made of laminated layers
• CPC Class Codes: B60C 5/14 with impervious liner or coating on the inner wall of the tyre
• CPC Class Codes: C08F 297/00 Macromolecular compounds obtained by successively polymerising different monomer systems using a catalyst of the ionic or coordination type without deactivating the intermediate polymer
• CPC Class Codes: C08F 8/10 Acylation
• CPC Class Codes: C08L 23/22 Copolymers of isobutene; Butyl rubber ; Homo- or copolymers of other iso-olefins
• CPC Class Codes: C08L 53/00 Compositions of block copolymers containing at least one sequence of a polymer obtained by reactions only involving carbon-to-carbon unsaturated bonds; Compositions of derivatives of such polymers
• CPC Class Codes: C08L 53/005 Modified block copolymers
• CPC Class Codes: C08L 91/00 : Compositions of oils, fats or waxes; Compositions of derivatives thereof

Abstract

The present invention is a pneumatic tire comprising an inner liner disposed on the inner side of the tire. The inner liner is composed of a sheet made of an elastomer composition containing a styrene-isobutylene-styrene triblock copolymer by more than or equal to 7 percent by mass and less than or equal to 93 percent by mass and an isobutylene-based modified copolymer containing a β-pinene component by more than or equal to 7 percent by mass and less than or equal to 93 percent by mass. In the inner liner, a ratio Gs/Gb between an average thickness Gb in a bead region Rb extending from a tire largest width position to a bead toe and an average thickness Gs in a buttress region Rs extending from the tire largest width position to a corresponding position Lu at a belt layer end is 0.30 to 0.75.

Claims

1-19. -19. (canceled)

20. A pneumatic tire comprising an inner liner disposed on an inner side of the tire,

said inner liner being composed of a sheet made of an elastomer composition containing an elastomer component in which a styrene-isobutylene-styrene triblock copolymer by more than or equal to 7 percent by mass and less than or equal to 93 percent by mass and an isobutylene-based modified copolymer containing a β

-pinene component by more than or equal to 7 percent by mass and less than or equal to 93 percent by mass are mixed, and

in said inner liner, a ratio Gs/Gb between an average thickness Gb in a bead region Rb extending from a tire largest width position to a bead toe and an average thickness Gs in a buttress region Rs extending from the tire largest width position to a corresponding position Lu at a belt layer end being 0.30 to 0.75.

21. The pneumatic tire according to claim 20, wherein said styrene-isobutylene-styrene triblock copolymer contains a styrene component at a content of 10 percent by mass to 30 percent by mass, and has a weight average molecular weight of 50,000 to 400,000.

22. The pneumatic tire according to claim 20, wherein the isobutylene-based modified copolymer is contained by more than or equal to 10 percent by mass and less than or equal to 90 percent by mass in the elastomer component of said elastomer composition.

23. The pneumatic tire according to claim 20, wherein β

-pinene in said isobutylene-based modified copolymer is contained at a content of 0.5 percent by weight to 25 percent by weight.

24. The pneumatic tire according to claim 20, wherein said isobutylene-based modified copolymer has a weight average molecular weight Mw of 30,000 to 300,000, and a value of a molecular weight distribution (weight average molecular weight Mw/number average molecular weight Mn) is less than or equal to 1.3.

25. The pneumatic tire according to claim 20, wherein the average thickness Gs in the buttress region of said inner liner is 0.05 mm to 0.45 mm.

26. A pneumatic tire comprising an inner liner disposed on an inner side of the tire,

said inner liner being composed of a polymer sheet made of an elastomer composition containing a SIBS modified copolymer obtained by modifying a styrene block portion of a styrene-isobutylene-styrene triblock copolymer with acid chloride having an unsaturated bond, and

in said inner liner, a ratio (Gs/Gb) between an average thickness Gb in a bead region Rb extending from a tire largest width position to a bead toe and an average thickness Gs in a buttress region Rs extending from the tire largest width position to a corresponding position Lu at a belt layer end being 0.30 to 0.75.

27. The pneumatic tire according to claim 26, wherein said acid chloride is methacrylic acid chloride.

29. The pneumatic tire according to claim 26, wherein said styrene-isobutylene-styrene triblock copolymer contains a styrene component at a content of 10 percent by mass to 30 percent by mass, and has a weight average molecular weight ranging from 50,000 to 400,000.

30. The pneumatic tire according to claim 26, wherein said SIBS modified copolymer is contained by more than or equal to 10 percent by mass and less than or equal to 100 percent by mass in an elastomer component.

31. The pneumatic tire according to claim 26, wherein an elastomer component of said elastomer composition is a mixture of the styrene-isobutylene-styrene triblock copolymer and the SIBS modified copolymer.

32. The pneumatic tire according to claim 26, wherein the elastomer composition has blended therein a tackifier by 0.1 part by mass to 100 parts by mass relative to 100 parts by mass of an elastomer component.

33. The pneumatic tire according to claim 26, wherein the average thickness Gs in the buttress region of said inner liner is 0.05 mm to 0.40 mm.

28. A pneumatic tire comprising an inner liner disposed on an inner side of the tire,

said inner liner being composed of a polymer sheet made of an elastomer composition containing a SIBS modified copolymer obtained by modifying a styrene block portion of a styrene-isobutylene-styrene triblock copolymer with acid anhydride, and

in said inner liner, a ratio (Gs/Gb) between an average thickness Gb in a bead region Rb extending from a tire largest width position to a bead toe and an average thickness Gs in a buttress region Rs extending from the tire largest width position to a corresponding position Lu at a belt layer end being 0.30 to 0.75.

34. A pneumatic tire having a carcass layer extending from a tread portion to bead portions on both sides thereof, a belt layer on an outer side of a crown portion thereof, and an inner liner disposed on an inner side of said carcass layer,

said inner liner being composed of a first layer disposed on an inner side of the tire, and a second layer disposed in contact with a rubber layer of said carcass layer,

(A) said first layer being an elastomer composition containing a thermoplastic elastomer, an ultraviolet absorber and an antioxidant, the thermoplastic elastomer containing at least one of a styrene-isobutylene-styrene block copolymer and a SIBS modified copolymer obtained by modifying a styrene block portion of a styrene-isobutylene-styrene block copolymer with one of acid chloride and acid anhydride having an unsaturated bond,

(B) said second layer containing an elastomer containing at least one of a styrene-isoprene-styrene block copolymer and a styrene-isobutylene block copolymer,

said first layer and said second layer being elastomer compositions containing the ultraviolet absorber and the antioxidant by 0.5 parts by mass to 40 parts by mass relative to 100 parts by mass of an elastomer component, and

in said inner liner, an average thickness Gs in a buttress region Rs extending from a tire largest width position to a corresponding position Lu at a belt layer end being thinner than an average thickness Gb in a bead region Rb extending from the tire largest width position to a bead toe.

35. The pneumatic tire according to claim 34, wherein a ratio (Gs/Gb) between the average thickness Gs in the buttress region and the average thickness Gb in the bead region of said inner liner is 0.5 to 0.7.

36. The pneumatic tire according to claim 34, wherein the average thickness Gs in the buttress region of said inner liner is 0.06 mm to 0.30 mm.

37. The pneumatic tire according to claim 34, wherein the elastomer composition of one of said first layer and said second layer has blended therein the SIBS modified copolymer by 5 percent by mass to 100 percent by mass of the elastomer component.

38. The pneumatic tire according to claim 34, wherein the elastomer composition of one of said first layer and said second layer has blended therein one of a tackifier and polyisobutylene.