Fast switching of liquid crystals on transferred reactive mesogens film via soft imprinting method

Unidirectional alignment of liquid crystal (LC) molecules is a prerequisite for advanced LC devices. We present a novel approach for the alignment of LC molecules. The process consists of reactive mesogen (RM) stamp production, RM transfer onto a polyimide (PI) layer, and LC device fabrication. Physicochemical and optical measurements show that thin films of RMs are well transferred onto PI layers from the RM stamp via contact printing. Uniform and unidirectional alignment of the LC molecules is achieved on the RM/PI surfaces. In addition, the pretilt angles of the LC molecules can be controlled by the compositions of the bottom PI layers. The no-bias-bend π-cell using RM/blended PI polymeric stacks exhibits superior electro-optical properties.

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