Abstract: A puncture-free inner tube has a hollow pipe shape, which is to be inserted in an annular space of an outer tire, which is to be mounted detachably on a tire rim having an annular shape. The tube contains a thermoplastic elastomer molded by injection molding into a transversal cross sectional shape that is similar or substantially similar to and is slightly larger than a transversal cross section of the annular space of the outer tire. The tube has a thickness that is gradually increased from a ground part toward an anti-ground part on a side of the tire rim. The tube is formed in an annular shape, and the tube is to be inserted in the annular space of the outer tire in a compressed state with a tensile stress of the outer tire.

Abstract: A puncture-free inner tube has a hollow pipe shape, which is to be inserted in an annular space of an outer tire, which is to be mounted detachably on a tire rim having an annular shape. The tube contains a thermoplastic elastomer molded by injection molding into a transversal cross sectional shape that is similar or substantially similar to and is slightly larger than a transversal cross section of the annular space of the outer tire. The tube has a thickness that is gradually increased from a ground part toward an anti-ground part on a side of the tire rim. The tube is formed in an annular shape, and the tube is to be inserted in the annular space of the outer tire in a compressed state with a tensile stress of the outer tire.