PURPOSE: To obtain a curable resin compsn. excellent in adhesion to a polyolefin substrate by subjecting a carboxylic anhydride and a hydroxylated (meth) acryloyl compd. to partial esterification.

CONSTITUTION: A curable resin compsn. mainly comprising a partial esterification product is obtd. by subjecting a carboxylic anhydride (pref. alicyclic or arom.) and a hydroxylated (meth)acryloyl compd. in an equivalent ratio of acid anhydride group of the former compd. to hydroxyl group of the latter of (1:1)-(1:2) to esterification. When necessary, 100 pts.wt. partial esterification product is compounded with up to 45 pts.wt. (meth)acrylic resin to give a curable resin compsn. A heat-sensitive adhesive contg. the compsn. can be pref. used by applying it to a polyolefin substrate, curing it with an active energy ray to form a cured resin layer, placing another adherend onto the resin layer, and heating it.