Pneumatic tire

Patent metadata

Field	Value
Publication number	US-9855798-B2
Application number	US-201214130109-A
Country	US
Kind code	B2
Filing date	Apr 10, 2012
Priority date	Jul 28, 2011
Publication date	Jan 2, 2018
Grant date	Jan 2, 2018

Abstract

The inner liner is composed of a polymer layer stack including a first layer containing an SIBS and a second layer containing at least one of an SIS and an SIB. At least one of the first layer and the second layer is a polymer composition containing one of a C4 polymer obtained by polymerizing a monomer unit having 4 carbon atoms, a layered clay mineral with an organic compound intercalated therein and at least one kind of rubber component selected from the group consisting of a natural rubber, an isoprene rubber and a butyl rubber. The second layer is arranged to come into contact with a rubber layer of the carcass ply. The inner liner has a thickness Ge at a shoulder position Pe exceeding 100% and being less than or equal to 500% of a thickness Gc at a crown central position Pc.

First claim

The invention claimed is:

1. A pneumatic tire comprising an inner liner disposed on the tire inside relative to a carcass ply bridged between a pair of bead portions, wherein
said inner liner is composed of a polymer layer stack including
(A) a first layer made of a polymer composition containing a styrene-isobutylene-styrene triblock copolymer by more than or equal to 5 mass % and less than or equal to 40 mass % and at least one kind of rubber component selected from the group consisting of a natural rubber, an isoprene rubber and a butyl rubber by more than or equal to 60 mass % and less than or equal to 95 mass %, and
(B) a second layer made of a polymer composition containing at least one of a styrene-isoprene-styrene triblock copolymer and a styrene-isobutylene diblock copolymer by more than or equal to 10 mass % and less than or equal to 85 mass % and containing at least one kind of rubber component selected from the group consisting of a natural rubber, an isoprene rubber and a butyl rubber by more than or equal to 15 mass % and less than or equal to 90 mass %,
said second layer is arranged to come into contact with the carcass ply, and
said inner liner has a thickness Ge at a shoulder position Pe being 120% to 500% of a thickness Gc at a crown central position Pc.

2. The pneumatic tire according to claim 1 , wherein said first layer is a polymer composition containing blended therein sulfur by more than or equal to 0.1 part by mass and less than or equal to 5 parts by mass, stearic acid by more than or equal to 1 part by mass and less than or equal to 5 parts by mass, zinc oxide by more than or equal to 0.1 part by mass and less than or equal to 8 parts by mass, an antioxidant by more than or equal to 0.1 part by mass and less than or equal to 5 parts by mass, and a vulcanization accelerator by more than or equal to 0.1 part by mass and less than or equal to 5 parts by mass, relative to 100 parts by mass of a polymer component.

3. The pneumatic tire according to claim 1 , wherein in a tire meridian section, when drawing a normal line L from a ground end Te of a tread portion inwardly in a tire radial direction relative to a boundary between said carcass ply and the inner liner and representing an intersection with said boundary by the shoulder position Pe, and representing an intersection of a tire central line CL and the intersection of said carcass ply and the inner liner by crown central position Pc, and representing a distance along a contour line of the inner liner from said shoulder position Pe to said crown central position Pc by a shoulder distance Wc, said inner liner has a thick portion formed in a region having a width of at least 10% of said shoulder distance We from said shoulder position Pe toward said crown central position Pc.

4. The pneumatic tire according claim 1 , wherein said inner liner has a thick portion formed in a region having a width of less than or equal to 50% of said shoulder distance We from said shoulder position Pe toward said crown central position Pc.

5. The pneumatic tire according to claim 1 , wherein, when representing a distance along a contour line of the inner liner from said shoulder position Pe to a tire largest width position Ps of said inner liner by a side distance Ws, said inner liner has a thick portion formed in a region having a width of at least 20% of said side distance Ws from said shoulder position Pe toward said largest width position Ps.

6. The pneumatic tire according to claim 1 , wherein said inner liner has a thick portion formed in a region having a width of less than or equal to t100% of said side distance Ws from said shoulder position Pe toward said largest width position Ps.

7. The pneumatic tire according to claim 1 , wherein said styrene-isobutylene-styrene triblock copolymer contains a styrene component at a content of 10 mass % to 30 mass %, and has a weight average molecular weight of 50,000 to 400,000.

Assignees

• Sugimoto Mutsuki
• Tsuchida Tsuyoshi
• Masui Tomomi
• OTAKE Reika
• Sumitomo Rubber Ind

Inventors

• Sugimoto Mutsuki
• Tsuchida Tsuyoshi
• Masui Tomomi
• OTAKE Reika

Classifications

• B29C48/40

  using two or more parallel screws {or at least two parallel non-intermeshing screws}, e.g. twin screw extruders · CPC title

• B29C2948/92857

  Extrusion unit · CPC title

• B29C2948/9259

  Angular velocity · CPC title

• B29C48/21

  the layers being joined at their surfaces · CPC title

• C08L53/00

  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 title