Liquid crystal aligning agent composition, method for preparing liquid crystal alignment film using same, and liquid crystal alignment film and liquid crystal display device using same

A liquid crystal aligning agent composition comprising:

• a polymer containing polyamic acid repeating units including a repeating unit of the following Chemical Formula 3;
• and
• 0.1% to 20% by weight, based on the total weight of the liquid crystal aligning agent composition, of a urea-based compound of the following Chemical Formula 1:
• wherein in Chemical Formula 1:
• A is a divalent to tetravalent functional group that is any one of an arylene group having 6 to 30 carbon atoms, an alkylene group having 1 to 20 carbon atoms, and an alkylene bisarylene group having 7 to 40 carbon atoms;
• n is an integer from 2 to 4;
• and
• one of R1 and R2 is a hydroxyalkyl group having 1 to 20 carbon atoms, and the other is hydrogen, a hydroxyalkyl group having 1 to 20 carbon atoms, an alkyl group having 1 to 20 carbon atoms, or an aryl group having 6 to 20 carbon atoms:
• wherein in Chemical Formula 3:
• X1 is a tetravalent organic group of the following Chemical Formula 10:
• wherein in Chemical Formula 10:
• R9 to R14 are each independently hydrogen or an alkyl group having 1 to 6 carbon atoms;
• L1 is any one selected from the group consisting of —O—, —CO—, —COO—, —S—, —SO—, —SO2—, —CR15R16—, —(CH2)t—, —O(CH2)tO—, —COO(CH2)tOCO—, —CONH—, phenylene, and a combination thereof;
• R15 and R16 are each independently hydrogen or an alkyl group or haloalkylhd group having 1 to 10 carbon atoms;
• and
• t is an integer from 1 to 10;
• and
• Y1 is a divalent organic group of the following Chemical Formula 6 or Chemical Formula 8-2:
• wherein in Chemical Formula 6:
• (1) among Q1 to Q8, one of Q2, Q4, Q5 and Q7 is nitrogen and the rest are carbons;
• D is —NR′—;
• and R′ is hydrogen or an alkyl group having 1 to 6 carbon atoms, or
• (2) among Q1 to Q8, at least one of Q2, Q4, Q5 and Q7 is nitrogen and the rest are carbons;
• and D is —O—,