| 摘要 |
PROBLEM TO BE SOLVED: To provide a method for forming multilayer coating film applying intermediate coating, aqueous base coating and clear coating by a wet-on-wet process so as to achieve a coating film with uniform appearance by applying a steel sheet and a plastic substrate. SOLUTION: There is provided a method for forming multilayer coating film by heating and curing three layers of an intermediate coating film, a base coating film and a clear coating film, wherein an organic solvent-based clear coating film is applied to form the clear coating film after aqueous intermediate coating is applied to form a coating film on a substrate and an aqueous base coating is applied to form the base coating film. In the resin solid content of 100 mass%, the aqueous base coating is characterized by containing (a) an acrylic resin emulsion which is 10-60 mass% in terms of solid content obtained by emulsion polymerizing a monomer mixture containing 0.2-20 mass% of a crosslinking monomer, (b) an aqueous acrylic resin which is 5-40 mass% in terms of solid content, (c) a melamine resin which is 20-40 mass% in terms of solid content, and (d) propylene glycol monoalkyl ether which is 10-40 mass% in the coating resin solid content of 100 mass%. COPYRIGHT: (C)2011,JPO&INPIT |
