| 摘要 |
<p>A method for forming a multi-layered coating film by applying a first coloring coating agent, a second coloring coating agent and a clear coating agent sequentially on a material to be coated and curing a first coloring coating film, a second coloring coating film and a clear coating film, which have been produced by the coating procedure, simultaneously by heating. In the method, the first coloring coating agent comprises (a1) a hydroxy-group-containing poly ester resin and (a2) a melamine resin, and the second coloring coating agent comprises (b1) a hydroxy-group-containing acrylic resin, (b2) a melamine resin and (b3) an acid catalyst, wherein the hydroxy-group-containing poly ester resin (a1) contains 1.0 to 8.0 mol/kg (in terms of resin solid content) of a linear alkylene group having 4 or more carbon atoms in the molecule thereof and has a hydroxy value of 30 to 160 mgKOH/g and a number average molecular weight of 1,000 to 6,000, the hydroxy-group-containing acrylic resin (b1) has a hydroxy value of 40 to 200 mgKOH/g and a weight average molecular weight of 3,000 to 15,000, and the melamine resin (b2) has a mononuclear melamine content of 40 mass% or more.</p> |
