| 摘要 |
PURPOSE:To obtain the naphthalate having high heat stability and excellent hue and transparency by selecting the amounts of the constituents of a specified catalyst and the ratio therebetween and using a specified ammonium compound. CONSTITUTION:This naphthalate is a polyester made from an acid component based on naphthalenedicarboxylic acid and a glycol component based on ethylene glycol, produced by using a catalyst comprising a magnesium compound, a clacium compound, a phosphorus compound and an antimony compound satisfying the relationships: 2.6mol<=(Mg+Ca)<=4.1, 1.3<=Mg/Ca<=6.0, 1.0<=P/(Mg+ Ca)<=1.5 and 1.0mol<=Sb<=3.0mol (wherein the amounts are represented in terms of the number of moles of the elements per 10<6>g of the acid component), and containing antimony acetate as the antimony compound and containing 0.04-0.4mol of an ammonium compound represented by the formula (wherein R1 to R4 are each H, alkyl, cycloalkyl, aryl or the like; and A is an anionic residue) per 10<6>g of the acid component. |
