| 摘要 |
<p><P>PROBLEM TO BE SOLVED: To provide a polyester composition which does not suffer from defects, such as whitened streaks and bubbles, even during high-speed molding, has long-time continuous moldability with reduced mold deposits and stable moldability with a reduced fluctuation in crystallization rate and can give a molding having transparency, heat-resistant dimensional stability, and flavor retention and to provide a polyester molding comprising the same. <P>SOLUTION: The polyester composition is one comprising solid-phase polymerized polyester chips mainly consisting of an aromatic dicarboxylic acid component and a glycol component and 0.1 to 5,000 ppm fine having a composition the same as that of the chips, wherein the ratio (IVs)/(IV) is 1.05 to 1.35 (wherein IVs is the intrinsic viscosity of the surface of each chip, and IV is the intrinsic viscosity of the chip), the ratio (IVc)/(IVs) is 0.70 to 0.95 (wherein IVc is the intrinsic viscosity of the center of the chip, and IVs is the intrinsic viscosity of the surface of the chip), and the increment of a cyclic ester oligomer is at most 0.50 wt.% when the polyester composition is molten at 290°C for 60 min. <P>COPYRIGHT: (C)2006,JPO&NCIPI</p> |
