EPOXY RESIN COMPOSITION FOR PHOTO-SEMICONDUCTOR SEALANT HAVING EXCELLENT MOISTURE RESISTANCE

摘要

PURPOSE:To provide the titled epoxy resin composition having excellent moisture resistance and transparency, by using a bisphenol A novolak resin and optionally an acid anhydride as the hardener. CONSTITUTION:The objective composition contains (A) an epoxy resin and (B) a bisphenol A novolak resin as a hardener at a ratio of preferably 1:(0.8-1.2) in terms of the epoxy group to the phenolic hydroxyl group, or contains (A') an epoxy resin and (B') the above novlak resin and an acid anhydride (e.g. phthalic anhydride) at a ratio of 1:(0.5-2) in terms of the epoxy group to the sum of the phenolic hydroxyl group and the acid anhydride group in the hardener. The amount of the acid anhydride is preferably <=30pts.wt. per 100pts.wt. of the novolak resin.