| 摘要 |
PURPOSE:To cause only predetermined positions in width direction of connecting yarns to be heat deteriorated, but to cause other positions to be thermally undeteriorated by a method in which the connecting yarns of each side of the insert corresponding to three sides of the U-shape of a fitting base part are respectively allowed to be heat deteriorable yarns and heat undeteriorable yarns at the temperature set for vulcanization at at least each one side, and such insert is used. CONSTITUTION:The connecting yarns 8 of each side of an insert 9 corresponding to three sides of the U-shape of a fitting base part 2 are respectively caused to be heat deteriorable yarns and heat undeteriorable yarns at the temperature set for vulcanization at at least each one side. For instance, the parts (a) and (c) corresponding to both sides of the U-shape have heat deteriorable yarns, and the part (b) corresponding to the bottom of the U-shape has heat undeteriorable yarns. That is to say, the connecting yarns at the positions where the distance between wires is expanded by being positioned at out side in bending operation, is formed with the heat deteriorable yarns. As the fiber material of the heat deteriorable yarn, polyethylene fiber (softening point ; 100 -115 deg.C, melting point ; 125-135 deg.C) etc., is preferable, and as the the fiber material of the heat undeteriorable yarn, aromatic nylon (aramid) fiber is preferable. |
