| 摘要 |
<p>PROBLEM TO BE SOLVED: To provide a coating composition from which a bilayer coating film with superior brightness can be formed even when the coating composition is a water-based coating composition having a high resin solid concentration.SOLUTION: The water-based coating composition comprises a resin for forming a coating film, a curing agent, a scaly pigment, and an amphiphilic compound. The amphiphilic compound includes at least one hydrophobic moiety (A) as a repeating unit and at least one hydrophilic moiety (B) as a repeating unit: the hydrophobic moiety (A) has at least one group selected from a set consisting of a propylene oxide group, butylene oxide group, linear or branched 4-40C saturated hydrocarbon group, linear or branched 4-40C unsaturated hydrocarbon group, 6-40C aromatic ring-containing group having an aromatic ring, and hydrophobic polymer segment; and the hydrophilic moiety (B) has at least one group selected from a set consisting of an ethylene oxide group and an acid group. The amphiphilic compound has a number average molecular weight of 1500 to 100000. When the water-based composition is controlled to have a viscosity of 780 to 820 mPa s at 20°C and 60 rpm measured by a B-type viscometer as a coating viscosity, the resin solid concentration in the coating composition is 25 to 40 mass%.</p> |
