Method of forming multilayered topcoat film

The present invention relates to a novel method of forming a multilayered topcoat film. Disclosed is a 3-coat 2-bake method of forming a multilayered topcoat film, comprising applying a first coating composition (A) and a second coating composition (B) to a substrate, thermally curing the two compositions, and applying and thermally curing a clear coating composition (C);the first coating composition (A) being an organic solvent-based colored coating composition;the second coating composition (B) being an organic solvent-based coating composition comprising an acrylic resin (b-1) having at least two side chains of different lengths, each of which is bonded to the main chain and has at least one hydroxyl group, a polyepoxide (b-2) and a crosslinking agent (b-3); andthe clear coating composition (C) being a powder coating composition (C-1) or an organic solvent-based coating composition (C-2) comprising a hydroxyl- and carboxyl-containing resin (c-2) and a polyepoxide (c-2). The method of the present invention is capable of forming a multilayered topcoat film excellent in intercoat adhesion, finish properties and film performance.