Method for forming coated film and intermediate coating material

An intermediate coating material for use in a method for forming a coated film comprising the steps of sequentially applying the intermediate coating material, a base coating material and a clear coating material on a substrate on which an electrodeposition coated film has been formed;

• and simultaneously curing the applied three layers by baking, which comprises:
• (a) 40 to 56% by weight of an urethane modified polyester resin having a number average molecular weight of 1,500 to 3,000, the urethane modified polyester resin being obtainable by polyaddition of:
• a hydroxyl group containing polyester resin having a glass transition point (Tg) of 40 to 80° C. which is obtainable by polycondensation of an acid ingredient including not less than 80% by mole of isophthalic acid with a polyhydric alcohol ingredient, with
• an aliphatic diisocyanate compound;
• (b) 10 to 30% by weight of a melamine resin;
• (c) 15 to 30% by weight of a blocked isocyanate compound, the blocked isocyanate compound being obtainable by blocking hexamethylene diisocyanate or an isocyanate compound derived from hexamethylene diisocyanate, with a compound having an active methylene group;
• (d) 4 to 15% by weight of a nonaqueous dispersion resin having core-shell structure, provided that percentages of (a) to (d) are based on the solid weight of the coating material resin;
• and
• (e) 0.4 to 2 parts by weight of flake-like pigment having a longitudinal size of 1 to 10 μm and a number average particle size of 2 to 6 μm, provided that the solid weight of the coating material resin is regarded as 100 parts.