SILICON-BASED LIQUID CRYSTAL ALIGNMENT AGENT, LIQUID CRYSTAL ALIGNMENT FILM AND LIQUID CRYSTAL DISPLAY ELEMENT

摘要

Provided is a liquid crystal alignment agent capable of forming a liquid crystal alignment film that can improve the speed of response following UV irradiation without causing a deterioration in vertically aligning force even in a liquid crystal display element of a type that improves the speed of response following UV irradiation by using liquid crystals to which a polymerizable compound is not added and by being treated in the same way as a PSA type device, a liquid crystal alignment film obtained from the liquid crystal alignment agent, and a liquid crystal display element having the liquid crystal alignment film. The liquid crystal alignment agent contains a polysiloxane (A) and a polysiloxane (B). Polysiloxane (A): A polysiloxane obtained by polycondensing an alkoxysilane containing an alkoxysilane represented by formula (1) and an alkoxysilane represented by formula (2). R1Si(OR2)3 (1) (R1 denotes a hydrocarbon group having 8 to 30 carbon atoms and optionally substituted with a fluorine atom, and R2 denotes an alkyl group having 1 to 5 carbon atoms.) R3Si(OR4)3 (2) (R3 denotes an alkyl group substituted with an acrylic group, a methacrylic group or an aryl group, and R4 denotes an alkyl group having 1 to 5 carbon atoms.) Polysiloxane (B): A polysiloxane obtained by polycondensing an alkoxysilane that contains 70% to 100% of an alkoxysilane represented by formula (3). Si(OR5)4 (3) (R5 denotes an alkyl group having 1 to 5 carbon atoms.)