Bladder and tire producing method

摘要

An object of the present invention is to provide a bladder which is unlikely to have a shapal variation along the inner wall surface of the tire and can satisfactorily extend along the inner wall surface of the tire. An inventive bladder is used to press the inner wall surface of the tire by a pressurized heating medium during the vulcanization of a green tire and is comprised of a fabric layer (purl stitched fabric layer 12) and rubber layers (silicone rubber layers 11, 13) placed one over another. Elongation rates of the fabric layer in warp direction and in weft direction both exceed 15% and satisfy: 0.4<=elongation rate in weft direction/elongation rate in warp direction <=6.0. Since the fabric layer has good extensibility, it can elongate with the rubber layers.