Pneumatic tire and method of manufacturing same

Patent metadata

Field	Value
Publication number	US-11534944-B2
Application number	US-201816646543-A
Country	US
Kind code	B2
Filing date	Sep 10, 2018
Priority date	Sep 11, 2017
Publication date	Dec 27, 2022
Grant date	Dec 27, 2022

Abstract

A pneumatic tire is vulcanized using a bladder provided with a coating layer formed of a release agent, and includes a sealant layer disposed on an inner surface of a tread portion in a tire circumferential direction, the release agent having a thickness of from 0.1 μm to 100 μm in at least a placement region of the sealant layer, detected using an electron microscope.

First claim

The invention claimed is:

1. A pneumatic tire vulcanized using a bladder provided with a coating layer formed of a release agent, the pneumatic tire comprising:
a sealant layer disposed on an inner surface of a tread portion in a tire circumferential direction; and
the release agent, the release agent having a thickness of from 0.1 μm to 100 μm in at least a placement region of the sealant layer, detected using an electron microscope.

2. The pneumatic tire according to claim 1 , wherein the sealant layer comprises butyl and/or natural rubber.

3. The pneumatic tire according to claim 2 , wherein
the sealant layer has a sheet-like shape extending in the tire circumferential direction, and
the sealant layer has a thickness of from 0.5 mm to 5.0 mm.

4. The pneumatic tire according to claim 3 , wherein the sealant layer is disposed with its lateral center positioned within a range of ±10 mm with respect to a tire equator.

5. The pneumatic tire according to claim 4 , wherein the sealant layer has a half width that is 100% or greater of a half width of a belt layer having a minimum width, and is 105% or less of a half width of a belt layer having a maximum width.

6. The pneumatic tire according to claim 1 , wherein
the sealant layer has a sheet-like shape extending in the tire circumferential direction, and
the sealant layer has a thickness of from 0.5 mm to 5.0 mm.

7. The pneumatic tire according to claim 1 , wherein the sealant layer is disposed with its lateral center positioned within a range of ±10 mm with respect to a tire equator.

8. The pneumatic tire according to claim 1 , wherein the sealant layer has a half width that is 100% or greater of a half width of a belt layer having a minimum width, and is 105% or less of a half width of a belt layer having a maximum width.

9. A method of manufacturing a pneumatic tire for vulcanizing a green tire using a bladder provided with a coating layer formed of a release agent, the method comprising:
disposing a sealant layer on an inner surface of a tread portion of a vulcanized pneumatic tire, the sealant layer being disposed in a placement region in a tire circumferential direction,
the release agent having a thickness of from 0.1 μm to 100 μm in at least the placement region of the sealant layer, detected using an electron microscope.

10. The method of manufacturing a pneumatic tire, according to claim 9 , wherein a step of forming the coating layer on the bladder has a coating time t (hour) and a temperature T (° C.) of the coating layer that satisfy conditions, t≥0.0001T 2 −0.07T+9, and T≤180° C.

11. The method of manufacturing a pneumatic tire, according to claim 10 , wherein the sealant layer comprises butyl and/or natural rubber.

12. The method of manufacturing a pneumatic tire, according to claim 11 , wherein
the sealant layer has a sheet-like shape extending in the tire circumferential direction,
the sealant layer has a thickness of from 0.5 mm to 5.0 mm, and
when the sealant layer is disposed on a tire inner surface, a sealant extruded from a die is disposed bonded directly to the tire inner surface by compression bonding.

13. The method of manufacturing a pneumatic tire, according to claim 11 , wherein
when the sealant layer is disposed on a tire inner surface, a sealant in a string-like shape is disposed applied in a continuous spiral form, and
the sealant layer is disposed with its lateral center positioned within a range of ±10 mm with respect to a tire equator.

14. The method of manufacturing a pneumatic tire, according to claim 13 , wherein the sealant layer has a half width that is 100% or greater of a half width of a belt layer having a minimum width, and is 105% or less of a half width of a belt layer having a maximum width.

15. The method of manufacturing a pneumatic tire, according to claim 9 , wherein the sealant layer comprises butyl and/or natural rubber.

16. The method of manufacturing a pneumatic tire, according to claim 9 , wherein
the sealant layer has a sheet-like shape extending in the tire circumferential direction, and
the sealant layer has a thickness of from 0.5 mm to 5.0 mm.

17. The method of manufacturing a pneumatic tire, according to claim 16 , wherein when the sealant layer is disposed on a tire inner surface, a sealant extruded from a die is disposed bonded directly to the tire inner surface by compression bonding.

18. The method of manufacturing a pneumatic tire, according to claim 9 , wherein when the sealant layer is disposed on a tire inner surface, a sealant in a string-like shape is disposed applied in a continuous spiral form.

19. The method of manufacturing a pneumatic tire, according to claim 9 , wherein the sealant layer is disposed with its lateral center positioned within a range of ±10 mm with respect to a tire equator.

20. The method of manufacturing a pneumatic tire, according to claim 9 , wherein the sealant layer has a half width that is 100% or greater of a half width of a belt layer having a minimum width, and is 105% or less of a half width of a belt layer having a maximum width.

Assignees

• Yokohama Rubber Co Ltd

Inventors

• Hoshiba Takashi
• Naruse Masahiro

Classifications

• B29D30/0654

  Flexible cores therefor, e.g. bladders, bags, membranes, diaphragms (elastic cores or mandrels for shaping of plastics B29C33/505; bags for isostatic pressing in compression moulding B29C43/12, B29C43/3642) · CPC title

• B29D2030/0695

  the sealant being in the form of one wide strip, e.g. a patch · CPC title

• B29C73/16

  Auto-repairing or self-sealing arrangements or agents {(incorporating auto-repairing or self-sealing arrangements or agents on or into tyres B29D30/0685)} · CPC title

• B29C35/02

  Heating or curing, e.g. crosslinking or vulcanizing {during moulding, e.g. in a mould}(cold vulcanisation B29C35/18 {; vulcanising tyres, presses therefor B29D30/0601}) · CPC title

• B29D30/06

  Pneumatic tyres or parts thereof {(e.g. produced by casting, moulding, compression moulding, injection moulding, centrifugal casting)} · CPC title