Multilayer structure, inner liner for pneumatic tire, and pneumatic tire

Patent metadata

Field	Value
Publication number	US-9724968-B2
Application number	US-201214118933-A
Country	US
Kind code	B2
Filing date	May 29, 2012
Priority date	May 31, 2011
Publication date	Aug 8, 2017
Grant date	Aug 8, 2017

Abstract

To provide a multilayer structure that may adhere to rubber material without the necessity of providing an adhesive layer, an inner liner and a pneumatic tire using the multilayer structure. According to the present invention, a multilayer structure 1 is formed by alternately laminating elastomer layers 3 containing thermoplastic elastomer and barrier layers 2 containing a gas barrier resin, wherein an outermost layer 4 laminated uppermost among layers constituting the multilayer structure 1 contains an elastomer component that may heat-adhere to diene rubber.

First claim

The invention claimed is:

1. A multilayer structure comprising a barrier layer containing a gas barrier resin and an elastomer layer containing thermoplastic elastomer,
wherein an outermost layer laminated uppermost among layers constituting the multilayer structure contains an elastomer component that may heat-adhere to diene rubber,
wherein the elastomer component of the outermost layer is a polymer containing both of a vulcanizable diene moiety which is derived from modified natural rubber, modified butadiene rubber, modified isoprene rubber, or modified styrene-butadiene rubber and urethane bond therein so as to improve flexibility of the outermost layer and adhesion between the outermost layer and an inner surface of a tire.

2. The multilayer structure according to claim 1 , wherein a ratio of a thickness of the elastomer layers occupying the multilayer structure is 80% or more.

3. The multilayer structure according to claim 1 , wherein the outermost layer and an inner surface of a tire adhere to each other by vulcanization.

4. The multilayer structure according to claim 1 , wherein elongation at break of the barrier layer conforming to JIS K 7113 at 20° C. and 65% RH is 100% or less.

5. The multilayer structure according to claim 1 , wherein the barrier layers and the elastomer layers are laminated to form seven or more layers in total.

6. The multilayer structure according to claim 5 , wherein the barrier layers and the elastomer layers are alternately laminated.

7. The multilayer structure according to claim 5 , wherein the barrier layers and the elastomer layers are laminated to form fifteen or more layers in total.

8. The multilayer structure according to claim 1 , wherein the barrier layer and the elastomer layer are crosslinked by irradiation of active energy rays.

9. The multilayer structure according to claim 1 , wherein oxygen permeability of the barrier layer at 20° C. and 65% RH is 10.0 cc·mm/m 2 ·day·atm or less.

10. The multilayer structure according to claim 1 , wherein a thickness of the barrier layer is 10 μm or less.

11. The multilayer structure according to claim 1 , wherein the gas barrier resin of the barrier layer is one or more resins having a polar group of carboxyl group, a carbonyl group, an amino group, an amide residue, OH, S, Cl or F.

12. The multilayer structure according to claim 11 , wherein the gas barrier resin of the barrier layer has a hydroxy group.

13. The multilayer structure according to claim 12 , wherein the elastomer component of the outermost layer has a modified group that may bond with the hydroxy group of the gas barrier resin.

14. The multilayer structure according to claim 11 , wherein the gas barrier resin of the barrier layer is ethylene-vinyl alcohol copolymer, modified ethylene-vinyl alcohol copolymer, polyamide or polyvinyl alcohol.

15. The multilayer structure according to claim 1 , wherein the elastomer layer includes at least one selected from polystyrene-based thermoplastic elastomer, polyolefin-based thermoplastic elastomer, polydiene-based thermoplastic elastomer, polyvinyl chloride-based thermoplastic elastomer, chlorinated polyethylene-based thermoplastic elastomer, polyurethane-based thermoplastic elastomer, polyester-based thermoplastic elastomer, polyamide-based thermoplastic elastomer and fluorine resin-based thermoplastic elastomer.

16. The multilayer structure according to claim 1 , wherein the inner liner is produced by co-extrusion molding.

17. An inner liner for a pneumatic tire using the multilayer structure according to claim 1 .

18. A pneumatic tire comprising the inner liner for a pneumatic tire according to claim 17 .

19. The multilayer structure according to claim 1 , wherein the modified natural rubber, modified butadiene rubber, modified isoprene rubber, or modified styrene-butadiene rubber is epoxidized natural rubber, epoxidized butadiene rubber, epoxidized isoprene rubber, or epoxidized styrene-butadiene rubber.

20. The multilayer structure according to claim 1 , wherein elongation at break of the elastomer layer conforming to JIS K 7113 at 20° C. and 65% RH exceeds 100%.

Assignees

• Kitano Hideki
• Amamoto Tetsuo
• Tanaka Takatsugu
• Takahashi Yuwa
• Hayashi Nahoto
• Hikasa Masao
• Tanaka Yusuke
• Bridgestone Corp
• Kuraray Co

Inventors

• Kitano Hideki
• Amamoto Tetsuo
• Tanaka Takatsugu
• Takahashi Yuwa
• Hayashi Nahoto
• Hikasa Masao
• Tanaka Yusuke

Classifications

• B32B25/08

  of synthetic resin · CPC title

• Y10T428/31504

  Composite [nonstructural laminate] · CPC title

• B32B27/302

  comprising aromatic vinyl (co)polymers, e.g. styrenic (co)polymers · CPC title

• C08L21/00

  Compositions of unspecified rubbers · CPC title

• B32B27/322

  comprising halogenated polyolefins, e.g. PTFE · CPC title