Rapid preparation of full color spectrum structural color coatings with iridescence effects via spray methods

Abstract

Differing from conventional spray methods that only produce amorphous photonic crystals, this study innovatively achieves the ordered assembly of poly(styrene-methyl methacrylate-acrylic acid) (P(St-MMA-AA)) microspheres into photonic crystals on the substrate surface by adjusting the spray distance, a simple parameter. The resulting coating exhibits a uniform and iridescent structural color. Simultaneously, employing this technique, P(St-MMA-AA) microspheres with three different diameters (234 nm, 178 nm, and 152 nm) were mixed pairwise and co-organized in an ordered manner on the substrate surface. By adjusting the mass ratio of the two types of microspheres, structural color coatings covering the full visible spectrum were facilely and efficiently prepared. The coatings exhibit iridescence, and the structural colors are true colors with high color quality. Additionally, violet, unattainable in traditional color mixing systems, was achieved. The structural color coatings obtained in this study demonstrate promising applications in areas such as environmentally friendly finishes, optical anti-counterfeiting, and true-color displays.