This paper focuses on preparing broadband reflective liquid crystal films through the diffusion of monofunctional and bifunctional monomers in a photoinduced trilayer system. By combining the hydrophilic and hydrophobic liquid crystal glass surface treatment technologies, the polymer network of polymer-stabilized cholesteric liquid crystal (PSCLC) itself serves as a diffusion channel to form a trilayer cholesteric liquid crystal composite system containing bifunctional monomers, a nematic liquid crystal composite system, and a cholesteric liquid crystal composite system containing monofunctional monomers. Utilizing the difference in the polymerization rates of monofunctional and difunctional polymerizable monomers, the monomers and chiral compounds diffuse relative to each other, so that the liquid crystal pitch exhibits a gradient distribution, and the broadened reflective width can reach up to 1570 nm. There is no doubt that new and improved processes and technologies offer important possibilities for preparing and applying PSCLC films.
Keywords: broadband reflection; cholesteric liquid crystal; photoinduced diffusion; pitch gradient.