| 摘要 |
<p>A polyester resin suitably used for forming preforms by compression forming, the polyester resin having an intrinsic viscosity of 0.70 to 1.00 dL/g and, a molecular weight distribution (Mz/Mn) of not smaller than 3.0, and a diethylene glycol content of not larger than 2.3 mol%. The polyester resin is effectively prevented from depositing on conveyer means of the synthetic resin feeding device, the timing of falling the molten resin mass onto the compression forming mold is not deviated and, besides, the resin can be extruded in an increased amount from the extruder without accompanied by an excess increase in the torque of the extruder. Therefore, the preforms can be formed by compression forming maintaining good productivity. Besides, since the resin has a high degree of fluidity, the preforms that are the formed articles are free of wrinkles, shade or forming distortion, featuring good formability.</p> |
