Material for liquid-crystal alignment film, liquid-crystal display element, process for its production and liquid-crystal display unit

摘要

A material for a liquid-crystal alignment film which comprises as a first polyamide a C3 to C10 alkyl ester of a polyamic acid whose acid anhydride residual group is any of: and as a second polyamide a C3 to C10 alkyl ester of a polyamic acid whose acid anhydride residual group is: is provided. The use of this material materializes a liquid-crystal alignment film having a high pre-tilt angle of molecules to the substrate, and having superiority in respect of electrical properties such as voltage holding ratio and residual DC voltage, adherence to substrates, printability, and step-covering properties.