Curable composition and photochromic composition

摘要

The present invention provides a curable composition which has excellent storage stability of the curable composition itself and with which a cured body having excellent scratch resistance can be formed. The present invention is a composition that comprises: a silsesquioxane monomer which has a radically polymerizable group within molecules and in which the content of a component having a molecular weight of 10000 or more according to a gel permeation chromatography method (GPC method) is less than 9 mass%; and a bifunctional polymerizable monomer represented by formula (1) (In the formula: B and B' are C2-15 straight-chain or branched-chain alkylene groups; c is a number having an average value of 1-20; in the event that a plurality of B is present, B may be the same or different groups; and R