| 摘要 |
PROBLEM TO BE SOLVED: To provide a phosphorus-containing polyester resin that can solve problems such as formation of aldehydes such as acetaldehyde or cyclic oligomers on molding or deterioration in transparency of molded products, exhibits excellent ultraviolet-shielding properties, decreases a content of metal atoms eluting from a polymerization tank, and can efficiently produce a hollow molded item or the like that is excellent in transparency, ultraviolet-shielding properties and flavor retention, is free from problems such as deterioration in transparency caused by mold stains on continuous molding and exhibits excellent dimensional stability under heat, a polyester resin composition comprising the same and its use. SOLUTION: The polyester resin is mainly constituted of an acid component comprised of 20-100 mol% of naphthalenedicarboxylic acid and 80-0 mol% of other carboxylic acids and a glycol component, has a terminal carboxy group concentration of at most 40 equivalent/ton and contains 100-10,000 ppm of phosphorous compounds in terms of the phosphorus atom and 500-10,000 ppm of water. COPYRIGHT: (C)2007,JPO&INPIT |
