An epoxy resin cured article has a high glass transition temperature and low dissipation factor. An epoxy resin composition from which the cured article can be having excellent solubility in solvents is used to produce the cured articles. A polyester as a curing agent of an epoxy resin composition having an aromatic polyhydroxy coumpound residue including an aryloxycarbonyl group at the molecule of the terminal, an aromatic polyvalent hydrocarbon group residue, and bulky structure, is used. Since the curing agent behaves as a polyfunctional curing agent, a cured article produced therefrom has a high crosslink density. Since highly polar hydroxyl groups are not formed during curing, a cured article has high glass transition temperature and a low dissipation factor. The cured article does not release low molecular weight carboxylic acids though hydrolysis of ester bonds at crosslinked bonds. Since the polyester has a bulky structure, the crystallization of the molecular chain is prevented and the solubility of the epoxy resin composition containing the polyester is excellent.
                            环氧
树脂固化物具有较高的
玻璃化转变温度和较低的耗散因子。使用一种环氧
树脂组合物生产固化物,该组合物在溶剂中具有极佳的溶解性。使用一种聚酯作为环氧
树脂组合物的固化剂,该聚酯具有芳香族多羟基
偶联剂残基,包括位于分子末端的芳氧基羰基、芳香族多价烃基残基和大块结构。由于固化剂具有多官能团固化剂的特性,由其制成的固化物具有较高的交联密度。由于在固化过程中不会形成高极性羟基,因此固化物的
玻璃化温度高,耗散因子低。固化物不会因交联键处的酯键
水解而释放出低分子量的
羧酸。由于聚酯具有大块结构,因此可防止分子链结晶,含有聚酯的环氧
树脂组合物的溶解性极佳。