First embodiment of a (meth)acrylic copolymer in the present invention includes following: a (meth)acrylic copolymer having at least one kind of constitutional unit selected from the group consisting of a constitutional unit (A1) having at least one kind of structure (I) selected from the group consisting of structures represented by the following formula (1), formula (2), or formula (3) and a constitutional unit (A2) having a triorganosilyloxycarbonyl group and a constitutional unit (B) derived from a macromonomer (b): (where, X represents —O—, —S—, or —NR14—, R14 represents a hydrogen atom or an alkyl group, R1 and R2 each represent a hydrogen atom or an alkyl group having from 1 to 10 carbon atoms, R3 and R5 each represent an alkyl group having from 1 to 20 carbon atoms, a cycloalkyl group, or an aryl group, and R4 and R6 each represent an alkylene group having from 1 to 10 carbon atoms).