| abstract |
[PROBLEMS] To be excellent in transparency, stable against ultraviolet light, free from yellowing, excellent in heat resistance and refractive index balance, and free from deformation and cracking in heating processes such as reflow soldering. The optical semiconductor sealing material which has the outstanding characteristic and can be used suitably as sealing materials, such as a light emitting element and a light receiving element in an optical semiconductor device (semiconductor light-emitting device) is provided. An optical semiconductor encapsulating material comprising a polymer obtained by radical polymerization of an alicyclic hydrocarbon group-containing methacrylic acid ester having 7 or more carbon atoms such as an adamantyl group, norbornyl group, dicyclopentanyl group, and the like, and It is an optical semiconductor sealing material containing a polymer obtained by radical polymerization of 50 to 97% by mass of an alicyclic hydrocarbon group-containing methacrylic acid ester and 3 to 50% by mass of a hydroxyl group-containing acrylate ester. [Selection figure] None |