There have conventionally been known a pneumatic tire in which a film formed of a thermoplastic resin or thermoplastic elastomer composition comprising a blend of a thermoplastic resin and an elastomer is used for an air impermeable layer (inner liner) disposed on the inner side of the tire (see a patent document 1, for example).
The opposite ends of the film in the circumferential direction of the tire are spliced to each other in an overlapping manner to form the above air impermeable layer. However, the film having the thermoplastic resin as a main component has a low adhesion. Therefore, even if the opposite ends of the film are spliced by pressing, the spliced opposite ends of the film are separated from each other during building of a green tire, which creates a problem of a mold release agent, applied to the inner surface of the tire, which comes in between the opposite ends of the film from the separated place of the film during curing of the green tire. If the mold release agent comes in between the opposite ends of the film as described above, adhesion of the film between the opposite ends is lowered, whereby the film is opened between the opposite ends during running, and the opened part becomes a starting point of tire trouble.
Further, the above film is subject to blemish because it is soft under high temperatures. Therefore, when the curing bladder is folded in order to remove a tire from a tire curing press after curing, the film receives a blemish if the curing bladder comes into contact with the film on the inner side of the tire and is rubbed against the surface of the film, which produces a problem of deteriorating an inner appearance of a brand-new tire.
Patent Document 1; Japanese Patent Application Kokai Publication HEI 10-35232
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