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CN-121986029-A - Pneumatic tire and method for manufacturing the same

CN121986029ACN 121986029 ACN121986029 ACN 121986029ACN-121986029-A

Abstract

Provided are a pneumatic tire and a method for manufacturing the same, wherein the tire thickness of a shoulder portion can be sufficiently ensured by applying work to a carcass structure, and both the durability and puncture sealing performance of the tire are achieved. In a pneumatic tire having a structure in which a bead core (5) of a carcass layer (4) is wound around a bead portion (3) from the inside to the outside, a distal end (4 e) of a wound-up portion (4B) of the carcass layer (4) is disposed at a position on the inner side in the tire width direction than an end (7 e) of a belt layer (7), a sealant layer (20) is formed on a tire inner surface (10) at the tread portion (1), and the tire width direction end (20 e) of the sealant layer (20) is disposed at a position on the shoulder portion and on the outer side in the tire width direction than the distal end (4 e) of the wound-up portion (4B) of the carcass layer (4).

Inventors

  • NARUSE MASAHIRO

Assignees

  • 横滨橡胶株式会社

Dates

Publication Date
20260505
Application Date
20241011
Priority Date
20231024

Claims (10)

  1. 1. A pneumatic tire comprising a tread portion extending in a tire circumferential direction and having a ring shape, a pair of side wall portions disposed on both sides of the tread portion, and a pair of bead portions disposed on inner sides of the side wall portions in a tire radial direction, wherein at least one carcass layer having a structure of rolling up around bead cores of the bead portions from inner side to outer side of the tire is provided between the pair of bead portions, and wherein a belt layer is disposed on an outer circumferential side of the carcass layer at the tread portion, The end of the turnup portion of the carcass layer is disposed at a position further inward in the tire width direction than the end portion of the belt layer, A sealant layer is formed on the inner surface of the tire at the tread portion, and an end portion of the sealant layer in the tire width direction is located at the shoulder portion and is disposed at a position outside the end of the rolled portion of the carcass layer in the tire width direction.
  2. 2. A pneumatic tire according to claim 1, wherein, A belt cover layer is provided on the tire outer peripheral side of the belt layer, and is disposed so as to cover at least the tire width direction end portion of the belt layer.
  3. 3. A pneumatic tire according to claim 1 or 2, wherein, The thickness of the sealant layer is in the range of 2.0mm to 5.0 mm.
  4. 4. A pneumatic tire according to any one of claim 1 to 3, wherein, The glass transition temperature of the sealant layer is in the range of-120 ℃ to-40 ℃.
  5. 5. A pneumatic tire according to any one of claim 1 to 4, wherein, The sealant of the sealant layer is composed of a silicone composition.
  6. 6. A pneumatic tire according to claim 5, wherein, The organosilicon composition is a two-component curing organosilicon.
  7. 7. A pneumatic tire according to any one of claim 1 to 6, wherein, The distance L from the belt layer to the sealant layer is 10mm or less at all positions of the belt layer located at the innermost side in the tire radial direction.
  8. 8. A pneumatic tire according to any one of claim 1 to 7, wherein, A sound absorbing member is provided on the inner side of the sealant layer in the tire radial direction along the tire circumferential direction.
  9. 9. A method for producing a pneumatic tire according to any one of claims 1 to 7, characterized in that, After manufacturing the pneumatic tire except for the sealant layer, When a sealant is applied to the inner surface of the tire at the tread portion to form the sealant layer, the temperature of the sealant applied to the inner surface of the tire is set to 70 ℃ or less.
  10. 10. The method for manufacturing a pneumatic tire according to claim 9, wherein, A sound absorbing member is provided on the inner side of the sealant layer in the tire radial direction along the tire circumferential direction.

Description

Pneumatic tire and method for manufacturing the same Technical Field The present invention relates to a pneumatic tire having a sealant layer on an inner surface of a tire at a tread portion and a method for manufacturing the same, and more particularly, to a pneumatic tire capable of sufficiently securing a tire thickness at a shoulder portion by applying work to a carcass structure and achieving both durability and puncture sealing (Puncture Seal) performance of the tire and a method for manufacturing the same. Background As a pneumatic tire having puncture sealing properties, a pneumatic tire in which a sealant layer made of an adhesive sealant is disposed on the inner surface of the tire at a tread portion has been proposed (for example, patent document 1). In a pneumatic tire provided with such a sealant layer, when a foreign object such as a nail penetrates into the tread portion, the adhesive sealant is entangled with the foreign object, and as the foreign object is detached, the adhesive sealant is guided to the penetration hole to exert a sealing effect. However, when the sealant layer is disposed on the inner surface of the tire, the centrifugal force during running increases due to an increase in the weight of the tire, and therefore the durability of the tire tends to deteriorate, and in particular, there is a problem in that a failure is likely to occur in the shoulder portion where the tire thickness becomes thin. Prior art literature Patent literature Patent document 1 Japanese patent laid-open publication No. 2003-080909 Disclosure of Invention Problems to be solved by the invention The present invention aims to provide a pneumatic tire and a method for manufacturing the same, wherein the tire thickness of a shoulder portion can be sufficiently ensured by applying work to a carcass structure, and the durability and puncture sealing performance of the tire can be simultaneously achieved. Means for solving the problems The pneumatic tire according to the present invention for achieving the above object includes a tread portion extending in a tire circumferential direction and having a ring shape, a pair of side wall portions disposed on both sides of the tread portion, and a pair of bead portions disposed on a tire radial direction inner side of the side wall portions, at least one carcass layer is provided between the pair of bead portions, a belt layer is disposed on an outer circumferential side of the carcass layer at the tread portion, the carcass layer has a structure in which a bead core around the bead portion is wound up from an inner side to an outer side of the tire, and the end of a wound-up portion of the carcass layer is disposed on a position on an inner side in the tire width direction than an end of the belt layer, a sealant layer is formed on a tire inner surface at the tread portion, and the end of the sealant layer in the tire width direction is disposed on a tire shoulder portion and on a position on an outer side in the tire width direction than an end of the wound-up portion of the carcass layer. The method for manufacturing a pneumatic tire according to the present invention for achieving the above object is a method for manufacturing the pneumatic tire, and is characterized in that when a sealant layer is formed by applying a sealant to an inner surface of a tire at the tread portion after manufacturing a pneumatic tire other than the sealant layer, a temperature of the sealant applied to the inner surface of the tire is set to 70 ℃. Effects of the invention In the pneumatic tire in which the carcass layer has a structure in which the bead cores around the respective bead portions are turned up from the inside to the outside of the tire, the distal end of the turned-up portion of the carcass layer is disposed at a position further toward the inside in the tire width direction than the end of the belt layer, and therefore the number of members at the shoulder portion can be increased, and therefore the tire thickness at the shoulder portion can be increased, the durability of the tire can be improved, and the air leakage amount at the shoulder portion can be suppressed even in the case where nails fall off after the nail is pierced. In such a carcass structure, the end portion of the sealant layer in the tire width direction is located at the shoulder portion and is disposed further outward in the tire width direction than the end of the rolled portion of the carcass layer, so that the puncture sealing property at the shoulder portion can be sufficiently ensured without taking measures to increase the thickness of the sealant layer. This can sufficiently secure the tire thickness of the shoulder portion and achieve both the durability and puncture sealing performance of the tire. In the pneumatic tire of the present invention, it is preferable that a belt cover layer is provided on the tire outer circumferential side of the belt layer, the belt cover layer being arrange