Preparation and Properties of Structural Color Pigments by Additive Color Method

Structural color is achieved by exploiting the interference, diffraction, and scattering effects between incident light and micro-/nano-structures. Physical vapor deposition (PVD) process is one of the commonly used methods for realizing structural color pigments by breaking vacuum-deposited films into micro-scale flakes. Significant efforts are typically required when a new color is needed as new structural designs and retuning deposition tools are necessary. Inspired by the color blending techniques of traditional painting and drawing, the solution to the aforementioned problems of structural color is to mix different structural color pigments for various colors. Different from traditional chemical pigments or organic dyes, the structural color follows the additive color mixing principles as it generates colors in the reflective format. In this work, spectra and color properties of structural color pigments before and after color mixing were investigated. Measured spectra of mixed pigments are consistent with theoretical calculations, and L*, a*, b* values are within the range of used basic pigments. The proposed mixing method of structural color here presents a more rapid and feasible way for the new color generation of structural color, which is of great help for improving the yield and reducing the cost when mass-producing.