Rubber composition for tire treads and pneumatic tire using same

Patent metadata

Field	Value
Publication number	US-9499009-B2
Application number	US-201314411317-A
Country	US
Kind code	B2
Filing date	Jun 11, 2013
Priority date	Jun 27, 2012
Publication date	Nov 22, 2016
Grant date	Nov 22, 2016

Abstract

A rubber composition for tire treads of the present technology contains a diene rubber, silica and a silane coupling agent, wherein the silane coupling agent is a polysiloxane represented by a specific average composition formula, the silica content is from 5 to 200 parts by mass per 100 parts by mass of the diene rubber, and the silane coupling agent content is from 1 to 20 mass % relative to the silica content.

First claim

What is claimed is:

1. A rubber composition for tire treads, containing a diene rubber, silica and a silane coupling agent; wherein
the silane coupling agent is a polysiloxane represented by an average composition formula of formula (1) below;
silica content is from 5 to 200 parts by mass per 100 parts by mass of the diene rubber; and
silane coupling agent content is from 1 to 20 mass % relative to the silica content:
(A) a (B) b (C) c (D) d (R 1 ) e SiO (4-2a-b-c-d-e)/2   (1)

(wherein, in formula (1), A denotes a divalent organic group containing a sulfide group; B denotes a monovalent hydrocarbon group having from 5 to 20 carbons; C denotes a hydrolyzable group; D denotes an organic group containing a mercapto group; R 1 denotes a monovalent hydrocarbon group having from 1 to 4 carbons; and a to e satisfy the relationships 0<a<1, 0<b<1, 0<c<3, 0<d<1, 0≦e<2, 0<2a+b+c+d+e<4).

2. The rubber composition for tire treads according to claim 1 , wherein, in formula (1), A is a group represented by formula (2) below, C is a group represented by formula (3) below, and D is a group represented by formula (4) below:
*—(CH 2 ) n —S x —(CH 2 ) n —*  (2)

(wherein, in formula (2), n denotes an integer from 1 to 10; x denotes an integer from 1 to 6; * denotes a bond position);
*—OR 2   (3)

(wherein, in formula (3), R 2 denotes an alkyl group having from 1 to 20 carbons, an aryl group having from 6 to 10 carbons, or an alkenyl group having from 2 to 10 carbons; * denotes a bond position);
*—(CH 2 ) m —SH  (4)

(wherein, in formula (4), m denotes an integer from 1 to 10; * denotes a bond position).

3. The rubber composition for tire treads according to claim 1 , wherein not less than 50 mass % of the diene rubber is aromatic vinyl-conjugated diene copolymer.

4. The rubber composition for tire treads according to claim 3 , wherein the aromatic vinyl-conjugated diene copolymer contains from 5 to 50 mass % aromatic vinyl, and vinyl bond content in the conjugated diene is from 5 to 80%.

5. The rubber composition for tire treads according to claim 1 , wherein a nitrogen adsorption specific surface area of the silica is from 100 to 300 m 2 /g.

6. A pneumatic tire using the rubber composition for tire treads described in claim 1 .

7. The rubber composition for tire treads according to claim 2 , wherein not less than 50 mass % of the diene rubber is aromatic vinyl-conjugated diene copolymer.

8. The rubber composition for tire treads according to claim 2 , wherein a nitrogen adsorption specific surface area of the silica is from 100 to 300 m 2 /g.

9. The rubber composition for tire treads according to claim 1 , wherein not less than 50 mass % of the diene rubber is aromatic vinyl-conjugated diene copolymer.

10. The rubber composition for tire treads according to claim 1 , wherein a nitrogen adsorption specific surface area of the silica is from 100 to 300 m 2 /g.

11. The rubber composition for tire treads according to claim 3 , wherein a nitrogen adsorption specific surface area of the silica is from 100 to 300 m 2 /g.

12. The rubber composition for tire treads according to claim 4 , wherein a nitrogen adsorption specific surface area of the silica is from 100 to 300 m 2 /g.

13. The rubber composition for tire treads according to claim 2 , wherein not less than 50 mass % of the diene rubber is aromatic vinyl-conjugated diene copolymer.

14. The rubber composition for tire treads according to claim 2 , wherein a nitrogen adsorption specific surface area of the silica is from 100 to 300 m 2 /g.

15. The rubber composition for tire treads according to claim 7 , wherein a nitrogen adsorption specific surface area of the silica is from 100 to 300 m 2 /g.

16. The rubber composition for tire treads according to claim 9 , wherein a nitrogen adsorption specific surface area of the silica is from 100 to 300 m 2 /g.

17. The rubber composition for tire treads according to claim 13 , wherein a nitrogen adsorption specific surface area of the silica is from 100 to 300 m 2 /g.

18. A pneumatic tire using the rubber composition for tire treads described in claim 2 .

Assignees

• Yokohama Rubber Co Ltd

Inventors

• Akahori Yayoi
• Sato Masaki

Classifications

• C08L21/00

  Compositions of unspecified rubbers · CPC title

• B60C1/0016 Primary

  Compositions of the tread · CPC title

• B60C1/00

  Tyres characterised by the chemical composition or the physical arrangement or mixture of the composition · CPC title

• C08K3/36

  Silica · CPC title

• B60C11/0008

  characterised by the tread rubber · CPC title