Patent ID: 9541797
Date: 2017-01-10
CPC Classifications: C09K,G02F

Claim:
1. A liquid crystal display device comprising: a pair of substrates; a liquid crystal layer that contains liquid crystal molecules and is disposed between the pair of substrates; an alignment film between the liquid crystal layer and at least one of the pair of substrates, the alignment film containing a polyamic acid or a polyimide with an imidization ratio of less than 100%, and a monomolecular film between the liquid crystal layer and the alignment film, wherein the polyamic acid or the polyimide of the alignment film includes a photo-reactive functional group, wherein the monomolecular film includes a structure that is derived from a silane-based surfactant that contains the following chemical formula (1) or (3): wherein each R wherein each R wherein the monomolecular film is a single layer formed of a same material that covers and is in contact with the entire surface of the alignment film so that the silane-based surfactant included in the monomolecular film reacts with carboxyl groups in the alignment film, to form a covalent bond that is between a structure derived from a carboxyl group in the alignment film and silicon in a structure derived from the silane-based surfactant, and is represented by the following chemical formula (2): thereby lowering the concentration of residual carboxyl groups contained in the alignment film without changing the imidization ratio, and wherein a pretilt angle of the liquid crystal molecules satisfies at least one of 0°<θ≦8° and 81°<θ≦90° due to the alignment film having undergone a photo-alignment treatment after forming the monomolecular film, which results in minimal changes in aligning ability of the alignment film.