PRODUCTION OF POLYETHYLENE NAPHTHALATE

PROBLEM TO BE SOLVED: To produce a polyethylene naphthalate resin, having a low content of by-products and good in color tone by carrying out the polycondensation of a dialkyl dicarboxylate with a glycol in the presence of a specific transesterification catalyst and a specified polycondensation catalyst. SOLUTION: The transesterification of (A) a dialkyl naphthalenedicarboxylate with (B) ethylene glycol is carried out and the polycondensation is then conducted. In the process, (C) one or more transesterification catalysts selected from respective compounds of Ca, Mg and Mn, (D) an diethylene glycol suppressant comprising (i) potassium acetate and (ii) a phosphorus compound and (E) a polycondensation catalyst comprising an antimony compound are added to the reactional system so as to satisfy formulas I to TV [M is the amount of the added component (C) expressed in terms of the metallic atoms (g atoms/t); K is the amount of the added component (i) expressed in terms of the K atoms (g atoms/t); P is the amount of the added component (ii) expressed in terms of the P atoms (g atoms/t); B is the amount of the added component (E) expressed in terms of the antimony atoms (g atoms/t)].