Abstract: Provided is a method for forming a multilayer coating film giving excellent low temperature impact resistance to a substrate that comprises a metal material and a plastic material. The method for forming a multilayer coating film comprises sequential steps of forming an uncured primer coating film, an uncured first colored coating film, an uncured second colored coating film and an uncured clear coating film on a substrate; and heating the same so as to simultaneously cure these 4 coating films, wherein the aqueous first colored paint and aqueous second colored paint are each a 1-package type paint composition containing a specific hydroxyl group-containing resin and a specific blocked polyisocyanate compound.

Abstract: Provided is a method for forming a multilayer coating film giving excellent low temperature impact resistance to a substrate that comprises a metal material and a plastic material. The method for forming a multilayer coating film comprises sequential steps of forming an uncured primer coating film, an uncured first colored coating film, an uncured second colored coating film and an uncured clear coating film on a substrate; and heating the same so as to simultaneously cure these 4 coating films, wherein the aqueous first colored paint and aqueous second colored paint are each a 1-package type paint composition containing a specific hydroxyl group-containing resin and a specific blocked polyisocyanate compound.

Abstract: An object of the present invention is to provide a method for forming a multilayer coating film, capable of achieving excellent curability under low-temperature, short-time conditions, and forming a multilayer coating film having excellent chipping resistance and an excellent finished appearance. This method comprises sequentially applying an aqueous first colored coating composition (X), an aqueous second colored coating composition (Y), and a clear coating composition (Z) to a substrate, and simultaneously bake-curing the resulting multilayer coating film. In this method, the aqueous first colored coating composition (X) comprises an aqueous film-forming resin (A) and a specific blocked polyisocyanate compound (B), and the clear coating composition (Z) comprises a hydroxy-containing acrylic resin (K) having a hydroxy value in a specific range, a polyisocyanate compound (L), and an organometallic catalyst (M) containing a metal compound (M1) selected from a specific range and an amidine compound (M2).

Abstract: An object of the present invention is to provide a method for forming a multilayer coating film, capable of achieving excellent curability under low-temperature, short-time conditions, and forming a multilayer coating film having excellent chipping resistance and an excellent finished appearance. This method comprises sequentially applying an aqueous first colored coating composition (X), an aqueous second colored coating composition (Y), and a clear coating composition (Z) to a substrate, and simultaneously bake-curing the resulting multilayer coating film. In this method, the aqueous first colored coating composition (X) comprises an aqueous film-forming resin (A) and a specific blocked polyisocyanate compound (B), and the clear coating composition (Z) comprises a hydroxy-containing acrylic resin (K) having a hydroxy value in a specific range, a polyisocyanate compound (L), and an organometallic catalyst (M) containing a metal compound (M1) selected from a specific range and an amidine compound (M2).