TTA186 is a trifunctional epoxy resin containing two glycidyl groups and one cycloaliphatic epoxy group. The additional cycloaliphatic epoxy group improves the crosslinking density and heat resistance. Unlike other cycloaliphatic epoxy resins which are limited by curing agents, TTA186 can almost produce high reaction activity with common epoxy curing agents due to the interaction between epoxy groups, and its cured products have excellent comprehensive properties.