US Patent 9285636 Liquid crystal display device

An image retention phenomenon and black unevenness generated after long-time operation in the liquid crystal device are prevented. By using a material having a polyamide acid ester as a precursor less likely to adsorb impurities on a boundary for an alignment film and a material having a dielectric constant anisotropy Δ∈ of 5 or less for liquid crystals, adsorption of an antioxidant dispersed in the liquid crystals is suppressed to prevent oxidation of the liquid crystals. The extent that impurities are intruded into the liquid crystals is reduced by restricting the dielectric constant anisotropy Δ∈ of the liquid crystals to 5 or less, thereby capable of preventing the image retention phenomenon and the black unevenness.