Structural coloured epoxy resin patterns prepared using thermochromic epoxy liquid crystal mixtures

Abstract

Cholesteric liquid crystal polymer network (CLCN) films have attracted much attention for their applications as optical filters and in displays, decoration, and anti-counterfeiting. Herein, two pairs of chiral bola-type epoxy liquid crystals with a cholesteric mesophase were synthesized. Their mixtures exhibit thermochromic behaviour. CLCN films with structural colours were prepared using their mixtures through photopolymerization. The Bragg reflection band and the handedness of the CLCN film can be controlled by changing the weight ratio of the chiral liquid crystals. Patterned CLCN films were prepared based on their thermochromic behaviour, the addition of a luminescent compound, or the handedness of the liquid crystal mixture, and they were potentially applied in decoration and anti-counterfeiting.