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CN-122029060-A - Pneumatic tire and method for manufacturing the same

CN122029060ACN 122029060 ACN122029060 ACN 122029060ACN-122029060-A

Abstract

Provided are a pneumatic tire and a method for manufacturing the same, wherein the adhesiveness between the inner surface of the tire and a sealant layer is improved, and the durability of the tire is improved. In a pneumatic tire provided with a tread portion (1) extending in the tire circumferential direction and having a ring shape, a pair of side wall portions (2) disposed on both sides of the tread portion (1), and a pair of bead portions (3) disposed on the inner sides of the side wall portions (2) in the tire radial direction, a release layer (10) containing a silicone composition is provided on the inner surface (Ts) of the tire, a sealant layer (20) is formed on the inner side of the release layer (10) in the tire radial direction at the tread portion (1), the sealant of the sealant layer (20) is composed of the silicone composition, and the absolute value of the difference between the contact angle of water with respect to the release layer (10) and the contact angle of water with respect to the sealant layer (20) is 30 DEG or less.

Inventors

  • NARUSE MASAHIRO

Assignees

  • 横滨橡胶株式会社

Dates

Publication Date
20260512
Application Date
20241011
Priority Date
20231024

Claims (8)

  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, A release layer containing a silicone composition is provided on the inner surface of the tire, and a sealant layer is formed on the inner side of the release layer in the tire radial direction of the tread portion, wherein the sealant of the sealant layer is composed of the silicone composition, and the absolute value of the difference between the contact angle of water with respect to the release layer and the contact angle of water with respect to the sealant layer is 30 DEG or less.
  2. 2. A pneumatic tire according to claim 1, wherein, The thickness of the release layer is in the range of 0.1-100.0 mu m.
  3. 3. A pneumatic tire according to claim 1 or 2, wherein, The glass transition temperature of the sealant is in the range of-120 ℃ to-40 ℃.
  4. 4. A pneumatic tire according to any one of claim 1 to 3, wherein, The silicone composition constituting the sealant is a two-component curable silicone.
  5. 5. A pneumatic tire according to any one of claim 1 to 4, 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.
  6. 6. A pneumatic tire according to any one of claim 1 to 5, 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.
  7. 7. A method for producing a pneumatic tire according to any one of claims 1 to 5, characterized in that, After manufacturing the pneumatic tire except for the sealant layer, When a sealant composed of a silicone composition 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 lower.
  8. 8. The method for manufacturing a pneumatic tire according to claim 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.

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 improving the adhesion between the inner surface of the tire and the sealant layer and improving the durability of the tire and a method for manufacturing the same. Background As a pneumatic tire having a puncture sealing property (Puncture Seal), 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. On the other hand, in the process of producing a pneumatic tire, when vulcanizing a green tire using an air bladder, the air bladder is easily attached (stuck) to the inner surface of the green tire, and therefore, the attachment of the green tire to the air bladder is prevented by applying a release agent to the inner surface of the green tire. However, when the compatibility between the inner surface of the tire to which the release agent is attached and the sealant layer is low, the inner surface of the tire and the sealant layer are difficult to fuse, and the adhesiveness between the inner surface of the tire and the sealant layer is low, which has a problem that the durability of the tire is adversely affected. 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 purpose of the present invention is to provide a pneumatic tire and a method for manufacturing the same, wherein the adhesiveness between the inner surface of the tire and a sealant layer is improved, and the durability of the tire is improved. Means for solving the problems The pneumatic tire for achieving the above object is provided with a tread portion extending in the 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 the tire radial direction inner sides of the side wall portions, wherein a mold release layer containing a silicone composition is provided on the tire inner surface, a sealant layer is formed on the tire radial direction inner side of the mold release layer at the tread portion, the sealant of the sealant layer is composed of the silicone composition, and the absolute value of the difference between the contact angle of water with respect to the mold release layer and the contact angle of water with respect to the sealant layer is 30 DEG or less. The method for producing a pneumatic tire according to the present invention for achieving the above object is a method for producing the above pneumatic tire, and is characterized in that when a sealant made of a silicone composition is applied to an inner surface of a tire at the tread portion to form the sealant layer after producing the pneumatic tire other than the sealant layer, the temperature of the sealant applied to the inner surface of the tire is set to 70 ℃. Effects of the invention The inventors of the present invention found that, when improving the adhesiveness between the inner surface of a tire and a sealant layer, it is effective to set the absolute value of the difference between contact angles to a specific range using the contact angle of water as an index of the compatibility of members. In the present invention, since the release layer containing the silicone composition is provided on the inner surface of the tire and the sealant layer is formed on the inner side in the tire radial direction of the release layer in the tread portion, the sealant of the sealant layer is composed of the silicone composition, and both the release layer and the sealant layer contain the silicone composition, which contributes to improvement of compatibility. Further, by setting the absolute value of the difference between the contact angle of water with respect to the release layer and the contact angle of water with respect to the sealant layer to a specific range (30 ° or less), the compatibility can be made very good. This can improve the adhesion between the inner surface of the tire and the sealant layer and improve the durability of the tire. In the pneumatic tire of the present invention, the thickness of the release layer is preferably in the range of 0.1 μm to 100.0 μm. This effectively improves the durability of the tire. Preferably, the glass transition temperature of the sealant is in the range of-120 ℃ to-40 ℃. By usi