(EN)
A process for polyester production improved in color tone and polymerizability, in which side reactions are inhibited from occurring during polycondensation. The process for polyester production comprises (A) a step in which a dicarboxylic acid or dialkyl dicarboxylate and a diol are subjected as major starting materials to esterification or transesterification in the presence of a catalyst to produce an oligomer having a degree of esterification or transesterification of 90% or higher and (B) a polycondensation step in which the oligomer is continuously condensation-polymerized in a molten state in reaction tanks disposed in multistage arrangement, and is characterized in that the polycondensation step (B) satisfies the relationship TMAX > T(omega) wherein TMAX ( DEG C) is the internal temperature of the tank having the highest internal temperature and T(omega) ( DEG C) is the internal temperature of the final tank.
(ZH) 本发明提供一种能控制缩聚反应时的副反应、改良色调及聚合性能的聚酯制造方法。本发明的聚酯制造方法包括:在具有(A)以二羧酸或二羧酸二烷基酯和二元醇为主原料、在催化剂的存在下进行酯化反应或酯交换反应、酯化率或酯交换率在90%以上的低聚物的制造工序;及(B)用多段反应槽将低聚物在熔融状态下连续进行缩聚反应的缩聚工序。其特征在于,(B)缩聚工序中内温最高的槽内温度设定为TMAX℃、最终槽的内温设定为T(ω)℃时,满足条件:TMAX℃>T(ω)℃。