Cholesteric liquid crystal-based printing inks with temperature and reflection angles response properties

Cholesteric liquid crystals (CLCs) are usually used in printing inks, and have a wide range of potential applications. Here, printable cholesteric liquid crystal-based printing inks have been fabricated. First, a series of cyclic side-chain CLC photonic inks containing chiral 4-(((40-(allyloxy)-[1,10-biphenyl]-4-yl)ox y)carbonyl)phenyl (2-isopropyl-5-methylcyclohexyl) succinate (M1) and chiral 4-(4-(4-Menthyloxy-4-o xobutanoyloxy)benzoyloxy)phenyl 4-allyloxybenzoate (M2), denoted as N1-N5, were obtained via graft copolymerization. The cyclic side-chain CLCs exhibit structural colors caused by dual photonic bandgaps, resulting in a wide variety of colors. Subsequently, the color patterns of CLC printing inks were fabricated by coating the CLCs on the black substrate by screen printing. The color patterns of CLC printing inks have shown excellent stability at room temperature for more than 1 year. CO 2022 Published by Elsevier B.V.