Liquid crystal mixtures with low birefringence for active-matrix LCD

The liquid crystal (LC) mixtures with fused ring systems such as Decahydronaphthalenes and Tetrahydronaphthlenes for reflective or transflective active-matrix liquid crystal display (AM-LCD) have higher durability than. LC mixtures with ester-components. These LC mixtures also have some problems such as low nematic-isotropic transition, temperature T-NI and high driving voltage. The improvement for driving voltage was carried out by using Tetrahydronaphthalene-component with moderate birefringence Deltan and large dielectric anisotropy Deltaepsilon. However, It was difficult to obtain LC mixtures with sufficiently low driving voltage, because of low T-NI and the comparatively high Deltan of tetrahydronaphthalene. We have improved these problems by introducing some newly developed LC components and optimization. We obtained the LC mixtures with low Deltan and low driving voltage; less than 0.075 of Deltan and about 4 V or less of driving voltage. These LC mixtures have high dug-ability with stable nematic phase at low temperature.