Thermally stable iridescent colors of a new low-molecular-weight cholesteric compound in the solid state and the application to fullcolor recording

Abstract

AbstractWe synthesized a series of new di-cholesteryl esters of several diacids. One of the compounds containing both of a diyne unit and long alkylene units, in the form of a thin solid film, showed stable iridescent colours in the visible region after rapid cooling process from the temperature of the cholesteric liquid crystalline phase. Measurement of selective reflectance of visible light, X-ray diffraction, optical rotation dispersion of the solid films proved that the films remained the cholesteric ordering of the molecules. The cholesteric structure in the solid films were completely stable at room temperature. The colour of the solid film was totally, partially or in imagewise manner changed into selected colours by adjusting the temperature of the surface just before the rapid cooling process. The property of this compound can be applicable to memory media with high density using the spectrum of light, or to thermosensitive full-colour recording materials.