To obtain a coating material composition suitable for forming a thin film having decreased color shading caused by color interference and provide a coated substrate having low interference color shading by applying the composition to a substrate.

The coating material composition is composed of a solid component and a solvent component. The solvent contains 5-90 pts.wt. of a low-boiling solvent having a boiling point of 40-100°C, 1-80 pts.wt. of a medium-boiling solvent having a boiling point of 100-150°C and 0.1-50 pts.wt. of a high-boiling solvent having a boiling point of ≥150°C based on 100 pts.wt. of the total solvent components. The coated substrate having decreased color shading by interference and especially useful as an antireflection substrate is produced by coating a surface of a substrate with the coating material composition to form a thin film on the surface.