| 摘要 |
PURPOSE:To obtain a polyester base excellent in static electricity applicability, slipperiness and transparency by reaction between terephthalic acid and a glycol in the presence of a specific compound bearing Mg, etc., followed by polycondensation in the presence of a phosphoric acid compound, etc., imidazole and silica and then making the resultant polymer into a film. CONSTITUTION:An esterification is made between a dicarboxylic acid, mainly terephthalic acid, and an alkylene glycol, mainly ethylene glycol; during which an ethylene glycol-soluble compound bearing such atom as Mg, Mn or Zn (e.g. magnesium acetate) is added to the system. On completing the esterification, (1) phosphoric acid or phosphorous acid or its ester and (2) an imidazole compound of the formula (R1 and R2 are each 1-8C alkyl or aromatic residue), and also, fine silica 0.1-4mum particle diameter is either continuously or intermittently added in the form of an ethylene glycol slurry to the system over a time before the esterification until the initiation of the polycondensation, and then the polycondensation is conducted to produce a polyester, which is then made into a film, thus obtaining the objective base. |
