To provide a process for preparing a polyester resin for powder coatings economically by the reuse at the esterification process of a distillate which is distilled off the reaction process and is not subjected to the rectification operation.
A preparing process of a polyester resin for powder coatings, comprising at least an esterification process and a polycondensation process of a terephthalic acid or an acid component composed mainly of this acid and of alcoholic components composed mainly of two or more kinds of diols containing 2-8 carbon atoms, reuses as a part of the alcoholic components in the esterification process an alcoholic component recovered by a single distillation of the distillate coming from the reaction process, in such a manner that a weight ratio of the reuse alcoholic component used in the esterification process to the pure alcoholic component is made to be 0.1-1.0 to 1.
SASABE TOMOAKI
MURAI MASUO
SHIMOO NOBUYOSHI
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