Preparation and characterization of the colored coating with low infrared emissivity based on nanometer pigment

Four colored coatings with low infrared emissivity were prepared by using polyurethane as adhesive, aluminum as filler and nanometer pigment as paint, respectively. The influence of nanometer pigment on color, surface gloss and infrared emissivity of composite coating was systematically investigated. The surface microstructure of coating was characterized and the mechanism of nanometer pigment was discussed in detail. These results indicate that the color of coatings changes significantly, the infrared emissivity increases slightly and the surface gloss decreases rapidly by the effect of nanometer pigment. Both flake aluminum and pigment particles show a uniform and compact distribution through the microscopic analysis. Additionally, a theoretical model is proposed to account for this mechanism from the analysis of the color and emissivity, which indicates that pigment particles play important roles in forming different particle arrangements between aluminum and colored pigments during the drying process, and nanometer pigment contribute to prepare the colored coating with low infrared emissivity because of its small particle size, low density and gravity.