EXPANSION OF CHOLESTERIC REFLECTION ZONE OF PHOTOPOLYMERIZABLE CHOLESTERIC LIQUID CRYSTAL, AND OPTICAL ELEMENT PRODUCED THEREBY

摘要

PROBLEM TO BE SOLVED: To provide a method for expanding a cholesteric reflection zone of a photopolymerizable cholesteric liquid crystal hardly requiring long-lasting UV-exposure. SOLUTION: This method for expanding a cholesteric reflection zone comprises a step for partially polymerizing a layer containing a photopolymerizable cholesteric liquid crystal by a prescribed short time exposure at a prescribed temperature by chemical rays, a step for maintaining the exposed layer at a prescribed temperature for a prescribed waiting time without the exposure (a dark phase), and a step for fixing the obtained layer by the exposure of the chemical rays at the prescribed temperature. The zone width and medium wavelength of the cholesteric reflection zone of the polymerized material are mutually independently regulated, and a long-lasting exposure to the UV can be avoided.