Optical filter comprising a glutamate copolymer and a method of making an optical filter comprising glutamate copolymer.

摘要

A method of producing an optical filter and an optical filter are provided.
<??>The method comprises applying a shearing force to a glutamate copolymer at a temperature higher than the melting point to orient said glutamate copolymer and heating said oriented glutamate copolymer at a constant temperature higher than the melting point. The optical filter consists essentially of a glutamate copolymer having thermotropic cholesteric liquid crystal properties and having the repeating units:
<CHEM>
wherein R1 is an alkyl group, a cycloalkyl group, an aryl group or an arylalkyl group having 10 or less carbon atoms, and R2 an alkyl group, a cycloalkyl group, an aryl group or an arylalkyl group having 6 to 30 carbon atoms, provided that R1 and R2 are different from each other; and wherein the copolymer contains m repeating units of the structure I and n repeating units of the structure II where m and n are numbers satisfying the following relationships 50 @</=@ m + n @</= @ 2000 and m/n = 80 to 10/20 to 90.