A hyper-reflective cholesteric liquid crystal polymer network with double layers

Cholesteric liquid crystal polymer networks (CLCNs) with hyper-reflectance have been widely studied for laser protection and energy-saving. Herein, double-layered CLCN films were prepared using single-layered CLCN films with opposite handedness. Since photopolymerization can be carried out in air, the double-layered CLCN films are feasible for being prepared with a large area. Due to the diffusion of the low-molecular-weight compounds of the top layer during the double-layered CLCN film preparation process, the Bragg reflection band of the bottom layer shifts to a long wavelength. Based on this fact, colourful patterns were prepared by printing and screen-printing. These patterns are suitably applied for decoration and anti-counterfeiting. Hyper-reflective double-layered cholesteric liquid crystal network films were prepared, which can be applied for decoration and anti-counterfeiting.