| 摘要 |
A zeolite polycondensation catalyst comprising an alkali- or alkaline earth metal aluminum silicate zeolite having an original water content of 12 to 30 weight % and a solubility, measured at 260 DEG C., in an esterification mixture consisting essentially of bis(hydroxy ethylene)terephthalate, of over 8.0 weight %, and an average particle size of less than 1.0 mu . The present invention is also a process for the production of polyester using this catalyst. |
