LIQUID CRYSTAL ALIGNING AGENT CONTAINING POLYIMIDE PRECURSOR HAVING THERMALLY CLEAVABLE GROUP AND/OR POLYIMIDE

摘要

A liquid crystal aligning agent for obtaining a liquid crystal aligning film which is excellent in adhesiveness with a sealing agent in a liquid crystal display element and a board|substrate, and the removal property of a decomposition product generated after ultraviolet irradiation is improved. A liquid crystal aligning agent containing at least one type of polymer selected from the group consisting of a polyimide precursor having a bond represented by the following formula (1) in the main chain and an imidized polymer of the polyimide precursor. (In the formula, R 1 , R 2 , R 3 and R 4 are each independently a hydrogen atom or a monovalent hydrocarbon group having 1 to 20 carbon atoms which may have a substituent, and D is a protecting group substituted with a hydrogen atom by heat. .)