| abstract |
Provided is an encapsulant for optical semiconductor devices, which is capable of enhancing the adhesion between a housing and the encapsulant when an optical semiconductor device is encapsulated in the housing, and which is also capable of enhancing the bonding reliability with respect to humidity. The encapsulant for optical semiconductor devices includes: a first organopolysiloxane having an alkenyl group bonded to a silicon atom and an aryl group bonded to a silicon atom, but not having a hydrogen atom bonded to a silicon atom; a second organopolysiloxane having a hydrogen atom bonded to a silicon atom and an aryl group bonded to a silicon atom; a catalyst for hydrosilylation reaction; and an organic compound having a titanium atom. |