US Patent 7850868 Lyotropic liquid crystalline mixture, coating liquid, and optical anisotropic film

The lyotropic liquid crystalline mixture of the present invention comprises at least a first azo compound and a second azo compound in relation of constitutional isomers wherein the first azo compound and the second azo compound are the constitutional isomers different in a binding site of at least an azo group. The first azo compound is preferably an azo compound wherein the azo group is bonded to an ortho-position of a hydroxyl group of an aminonaphthol skeleton. The second azo compound is preferably an azo compound wherein the azo group is bonded to an ortho-position of an amino group of an aminonaphthol skeleton.