| abstract |
PROBLEM TO BE SOLVED: To provide a curable composition for sealing an optical material which uses a phenyl-modified polyorganosiloxane having a high refractive index as a base polymer and does not generate cracks or peel off from a substrate even when heated. An alkenyl group- and phenyl group-containing polyorganosiloxane having a heating loss of 200 ° C. × 1 hour of 1.5% by weight or less is used as a base polymer of a curable composition for sealing an optical material. [Selection figure] None |