摘要 |
PURPOSE:To obtain constant spherical particles of the titled resin in high yield, by dissolving saturated polyester resin pellets in dimethylacetamide or dimethylformamide in a nonoxidizing atmosphere under pressure, slowly cooling the solution and depositing fine resin particles in the slow cooling step. CONSTITUTION:(A) 1-50pts.wt. saturated polyester resin pellets is dissolved in (B) 100pts.vol. dimethylacetamide or dimethylformamide in a vessel having a stirring and heating devices in a nonoxidizing atmosphere under pressure while heating and then the resultant solution is slowly cooled to deposit fine particles of the resin pellets (A) in the slow cooling step. Further, temperature is then lowered to separate the solvent (B) and deposited fine particles by filtration to afford the aimed spherical particles having 10-60mum particle diameter in high yield. |