| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for stably producing a polyester containing little cobalt compound as a hue regulator and excellent in hue. SOLUTION: The method for producing the polyester is provided, wherein the polyester is composed of an ethylene aromatic dicarboxylate as the main recurring unit and contains 0.1-10 ppm of a hue regulator and 10 ppm or less of cobalt element. This method meets all of the following requirements: (1) The hue regulator, in the form of an ethylene glycol solution or dispersion containing 0.01-1 mass% thereof, is added to the polyester production system. (2) The above hue regulator solution or dispersion is kept at 100-180°C before it is charged into the polyester production process. (3) The above hue regulator solution or dispersion is added to the polyester reaction vessel in the early to middle stage of the polyester production process. COPYRIGHT: (C)2008,JPO&INPIT
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