LIQUID CRYSTAL ALIGNING AGENT

摘要

PROBLEM TO BE SOLVED: To obtain a liquid crystal aligning agent which can give the optimal pretilt angle according to the specification of a liquid crystal display element and can give a liquid crystal display having excellent reliability by including a polycarbonate and a polyamic acid as the resin component. SOLUTION: The polycarbonate comprises repeating units represented by formula I (wherein X is an aromatic group and/or an aliphatic group). The polyamic acid comprises repeating units represented y formula II (wherein R<1> is a tetravalent organic group; an R2 is a divalent organic group). The resin component being the polymer of formula I is obtained by introducing phosgene into an alkaline aqueous solution of a bisphenoxy compound or a diol compound and removing the solvent from the solution. The bisphenoxy compound used is desirably e.g. 2,2-bis(4-hydroxyphenyl)propane. The polyamic acid of formula II is obtained by reacting an aromatic acid anhydride or an aliphatic acid dianhydride with an aromatic or aliphatic diamine in a polar solvent. It is desirable that the polycarbonate of formula I constitutes at least 20 wt.% of the total polymer.