Improvement in response speed for bistable light switching of (liquid crystalline polymer/low molecular weight liquid crystals) ternary composite system in induced smectic state

Bistable light switching characteristics of the composite system composed of side chain type liquid crystalline polymer (LCP) and two kinds of low molecular weight liquid crystals (LCs) have been investigated. Each component was in a nematic state but the ternary composite showed an induced smectic phase over the wide ranges of both mixing concentration and temperature. The reversible turbid (light scattering)-transparent switching was observed upon the application of electric fields with low and high frequencies, respectively. Both transparent and turbid states of the ternary composite could be maintained stably, even though an electric field was turned off. The ternary .composite system exhibited novel characteristics on bistable and reversible light switching. The response speed for bistable light switching could be remarkably improved by reducing the LCP fraction, maintaining an induced smectic state. Then, a novel type of the (LCP/LCs) composite system with a short response time at room temperature was realized for that with bistable and reversible light switching.