Epoxy resin compositions and their cured compositions comprise, as essential components, an epoxy resin and a phenolic resin of a structure formed by crosslinking a phenolic compound with particular trifunctional aromatic residual groups. Preferably, the phenolic resin and the epoxy resin are mixed at such a ratio that 0.5-1.5 moles of hydroxyl groups of the phenolic resin are contained per mole of epoxy groups of the epoxy resin. The resin compositions are low in modulus of elasticity, coefficient of linear expansion and water absorption and are excellent in heat resistance and solder cracking resistance. The resin compositions can be used as semiconductor sealants owing to their superb solder cracking resistance.
环氧
树脂组合物及其固化组合物的基本成分包括环氧
树脂和
酚醛
树脂,
酚醛
树脂的结构是由
酚类化合物与特定的三官能芳香残基交联而成。
酚醛
树脂和环氧
树脂的混合比例最好是每摩尔环氧
树脂的环氧基团含有 0.5-1.5 摩尔的
酚醛
树脂羟基。这种
树脂组合物的弹性模量、线膨胀系数和吸
水性较低,耐热性和耐焊料开裂性极佳。由于具有极佳的耐焊料开裂性,这种
树脂组合物可用作半导体密封剂。