| abstract |
(57) Abstract: A phosphine oxide compound represented by the following formula (1) as an essential component as a curing accelerator, an epoxy resin obtained from biphenols, and a curing agent: An epoxy resin composition comprising a bifunctional or more functional ester-containing compound or ester-containing resin in which 10 mol% to 100 mol% of hydroxyl groups are esterified by an aliphatic acyl group. (In the formula, R 1 to R 6 represent a hydrogen atom, an alkyl group having 1 to 10 carbon atoms or an aryl group or an aralkyl group having 6 to 10 carbon atoms.) In particular, the present invention provides an epoxy resin composition which provides a package having more excellent crack resistance than a conventional cured product in a semiconductor sealing material application. |