| 摘要 |
PURPOSE:To improve elasticity recoverability and profile stability by melting and spinning thermoplastic polyester, extending it at a specific extension multiplying factor, molding a monofilament with a specific diameter into a spiral, and specifying the spring index. CONSTITUTION:A monofilament with a diameter of less than 1.2mm. made by melting and spinning thermoplastic polyester and extending it at an extension multiplying factor of three times or more is molded into a spiral to constitute a synthetic resin coil 1 with its spring index set to 3-10. In this case, polyethylene terephthalate or the like is used for thermoplastic polyester. The polyester monofilament is produced by extruding a molten polymer through a spinning nozzle and spinning it, cooling it and applying oil to it, then extending and heat-fixing it. The spring index D/d of the coil 1 is set to 3-10, particularly in a range of 4-8, where D is the diameter of the coil and (d) is the diameter of the monofilament. |
