or an acid anhydride group, and Y in the formula (6) is preferably an epoxy group, an amino group or a hydroxyl group. [1417] When the polar group-containing olefin copolymer or the thermoplastic resin composition is used as the coating property improver or the printability improver and when X is a hydroxyl group and R3 is an aliphatic hydrocarbon group of 9 or less carbon atoms, preferably 8 or