Curable resinous composition comprising epoxy resin and silicon-containing elastomeric polymer

A curable resinous composition comprising:

• (A) an organic elastomeric polymer having at least one silicon-containing functional group in a molecule,
• (B) an epoxy resin,
• (C) a silicone compound having a silicon-containing group and a functional group reactive with an epoxy group, and
• (D) a curing agent for the epoxy resin, wherein the silicon-containing functional group of the organic elastomeric polymer (A) and/or the silicone compound (C) is a group of the formula:
• ##STR25## wherein X is a hydroxyl group or a hydrolyzable group, R.sup.1 is a monovalent hydrocarbon group having 1 to 20 carbon atoms or an organosiloxy group, "a" is 0, 1, 2 or 3, "b" is 0, 1 or 2 provided that the total of "a" and "b" is at least 1, and "m" is 0 or an integer of 1 to 18, and a weight ratio of (A) to (B) is from 1:100 to 100:1 and a weight ratio of (A)+(B) to (C) is from 100:0.1 to 100:20.