| abstract |
A process for preparing polyesters which comprises (1) a first step of esterifying (A) a difunctional carboxylic acid containing at least 60 mole% of an aromatic dicarboxylic acid, (B) 0 to 80 mole%, based on component (A), of an aliphatic diol and (C) an aromatic monohydroxy compound in an amount of at least 210 mole% as a total of it and component (B) based on component (A), the esterification being performed until the degree of esterification reaches 80 to 98%, and (2) a second step of adding 0 to 80 mole%, based on component (A), of component (B), and an aromatic dihydroxy compound (D) in an amount of 95 to 130 mole% as a total of it and component (B) based on component (A), to the reaction product obtained in the first step and reacting the mixture, the total amount of components (B) used in the first and second steps being 0 to 80 mole% based on component (A). |