Ply coat rubber composition and a tire comprising a ply coat rubber composition

Patent metadata

Field	Value
Publication number	US-11441019-B2
Application number	US-202016904034-A
Country	US
Kind code	B2
Filing date	Jun 17, 2020
Priority date	Jun 21, 2019
Publication date	Sep 13, 2022
Grant date	Sep 13, 2022

Abstract

In accordance with the invention, a ply coat rubber composition for a tire ply comprises from 60 phr to 90 phr of natural rubber, from 10 phr to 40 phr of synthetic polyisoprene, from 30 phr to 80 phr of pre-silanized and precipitated silica, from 0.1 phr to 5 phr of a cobalt salt, up to 15 phr of carbon black, up to 5 phr of resin, and up to 8 phr of oil. Moreover, the invention is directed to a tire comprising such a rubber composition.

First claim

The invention claimed is:

1. A ply coat rubber composition, the rubber composition comprising: 60 phr to 100 phr of natural rubber, up to 40 phr of synthetic polyisoprene, 30 phr to 80 phr of pre-silanized precipitated silica, 0.1 phr to 5 phr of a cobalt salt, 0 to 15 phr of carbon black, 0 to 5 phr of a resin, a silica coupling agent, wherein the phr ratio of said pre-silanized precipitated silica to the silica coupling agent is between 5:1 and 30:1, and 0 to 8 phr of oil.

2. The ply rubber composition of claim 1 wherein the natural rubber is present at a level which is within the range of 70 phr to 80 phr, wherein the synthetic polyisoprene is present at a level which is within the range of 20 phr to 30 phr, wherein the pre-silanized precipitated silica is present at a level which is within the range of 50 phr to 60 phr, and wherein the carbon black is present at a level which is within the range of 2 phr to 10 phr.

3. The ply rubber composition of claim 1 , wherein the cobalt salt is present at a level which is within the range of 0.2 phr to 2 phr.

4. The ply rubber composition of claim 1 wherein the ply rubber composition is further comprised of 1 phr to 20 phr of zinc oxide and/or 1 phr to 15 phr of sulfur.

5. The ply rubber composition of claim 1 wherein the pre-silanized precipitated silica has a CTAB adsorption surface area which is within the range of 130 m 2 /g to 210 m 2 /g.

6. The ply rubber composition of claim 1 wherein said pre-silanized precipitated silica is precipitated silica pre-reacted with a sulfur-containing silane which is comprised of bis(3-triethoxysilylpropyl)polysulfide containing an average of from 2 to 5 connecting sulfur atoms in its polysulfidic bridge, or an alkoxyorganomercaptosilane.

7. The ply rubber composition of claim 1 , wherein the surface of said pre-silanized precipitated silica is pre-hydrophobated with a hydrocarbon chain material having at least 4 carbon atoms along its chain.

8. The ply rubber composition of claim 1 , wherein the pre-silanized precipitated silica has a hydrocarbon chain material on its surface, and wherein the carbon on the surface of the pre-silanized precipitated silica is present at a level which is within the range of 3 weight percent to 8 weight percent.

9. The ply rubber composition of claim 1 wherein the ply rubber composition contains less than 5 phr of oil and wherein the ply rubber composition is essentially free of polyethylene glycol.

10. A ply rubber composition, the rubber composition comprising: 60 phr to 100 phr of natural rubber, up to 40 phr of synthetic polyisoprene, 30 phr to 80 phr of pre-silanized precipitated silica, 0 to 15 phr of carbon black, 0 to 5 phr of a resin, a silica coupling agent, wherein the phr ratio of said pre-silanized precipitated silica to the silica coupling agent is between 5:1 and 30:1, and 0 to 8 phr of oil.

11. The ply rubber composition of claim 10 wherein the natural rubber is present at a level which is within the range of 70 phr to 80 phr, wherein the synthetic polyisoprene is present at a level which is within the range of 20 phr to 30 phr, wherein the pre-silanized precipitated silica is present at a level which is within the range of 50 phr to 60 phr, and wherein the carbon black is present at a level which is within the range of 2 phr to 10 phr.

12. The ply rubber composition of claim 10 wherein the ply rubber composition is further comprised of 1 phr to 20 phr of zinc oxide and/or 1 phr to 15 phr of sulfur.

13. The ply rubber composition of claim 10 wherein the pre-silanized precipitated silica has a CTAB adsorption surface area which is within the range of 130 m 2 /g to 210 m 2 /g.

14. The ply rubber composition of claim 10 wherein said pre-silanized precipitated silica is precipitated silica pre-reacted with a sulfur-containing silane which is comprised of bis(3-triethoxysilylpropyl)polysulfide containing an average of from 2 to 5 connecting sulfur atoms in its polysulfidic bridge, or an alkoxyorganomercaptosilane.

15. The ply rubber composition of claim 10 wherein the surface of said pre-silanized precipitated silica is pre-hydrophobated with a hydrocarbon chain material having at least 4 carbon atoms along its chain.

16. The ply rubber composition of claim 10 wherein the pre-silanized precipitated silica has a hydrocarbon chain material on its surface, and wherein the carbon on the surface of the pre-silanized precipitated silica is present at a level which is within the range of 3 weight percent to 8 weight percent.

17. The ply rubber composition of claim 10 wherein the ply rubber composition contains less than 5 phr of oil and wherein the ply rubber composition is essentially free of polyethylene glycol.

18. A tire having at least one ply selected from the group consisting of a belt ply, a carcass ply, an overlay ply, and a ply strip, wherein at least one of the plies or the ply strip of the tire comprises a rubber composition comprising: from 60 phr to 100 phr of natural rubber, from 0 phr to 40 phr of synthetic polyisoprene, from 30 phr to 80 phr of pre-silanized precipitated silica, optionally from 0.1 to 5 phr of a cobalt salt, from 0 phr to 15 phr of carbon black, from 0 phr to 5 phr of resin, a silica coupling agent, wherein the phr ratio of said pre-silanized precipitated silica to the silica coupling agent is between 5:1 and 30:1, and from 0 phr to 8 phr of oil.

19. The tire of claim 18 wherein the ply or the ply strip comprises a textile which is calendered on both sides with the rubber composition.

20. The tire of claim 18 wherein the ply or the ply strip is comprised of a plurality of essentially parallelly extending metal wires which are coated with the rubber composition, and wherein optionally the plurality of parallelly extending metal wires define a plane of parallelly extending metal wires which are calendered on both sides with the rubber composition.

Assignees

• Goodyear Tire & Rubber

Inventors

• Welter Carolin Anna
• Knepper Jean-Claude
• Paulus Marc-André
• Buehler Betul
• Johnson Dawn Michelle
• Schmit Philippe
• Nawale Vaibhav

Classifications

• B60C2001/0083

  Compositions of the cap ply layers · CPC title

• B60C9/0007

  Reinforcements made of metallic elements, e.g. cords, yarns, filaments or fibres made from metal · CPC title

• C08L2205/03

  containing three or more polymers in a blend · CPC title

• B60C2001/0066

  Compositions of the belt layers · CPC title

• B60C2009/0021

  Coating rubbers for steel cords · CPC title