EPOXY RESIN COMPOSITION FOR SEALING OPTICAL ELEMENT

摘要

PURPOSE:To provide the subject composition having excellent transparency, excellent heat resistance and low stress by compounding a specific epoxy resin with a specified amount of a specific polybutadiene epoxidated product. CONSTITUTION:The objective composition comprises (A) 100 pts.wt. of one or more epoxy resins selected from among a bisphenol type epoxy resin, an aliphatic epoxy resin and a heterocyclic epoxy resin and (B) 5-50 pts.wt. of a polybutadiene epoxidated product of the formula (a) is 0.20-0.30; (b) is 0.10-0.30; (c) is 0.50-0.60; (n) is 15-60).