| 摘要 |
PURPOSE:To produce the titled belt excellent in elongation, relaxation of stress and tensile strength and superior in heat resistance, cold resistance and oil resistance by a method wherein a thermoplastic polyester extruded into the shape of a round rod is stretched by passing it between rollers, heat-treated, and cut up, and the end faces of the cut-up pieces are fused with each other. CONSTITUTION:A thermoplastic polyester extruded by an extruder 1 into the shape of a round rod is wound several times around a roller 2 while being gradually cooled at room temperature, then it is stretched by winding it several times around a roller 3 rotated at a circumferential speed which is two to seven times as high as that of the roller 2, heat-treated while passing through a heater 4 kept at an atmospheric temperature of 130-200 deg.C, and taken up by a take-up roll 5 after being cooled. Then the round rod of polyester thus treated is cut up to predetermined size, and the end faces of the cut-up pieces are fused with each other to obtain a round belt. |
