Photoalignment agent and liquid crystal display device including the same

A liquid crystal display comprising:

• a first substrate;
• a thin film transistor disposed on the first substrate;
• a first electrode connected to the thin film transistor;
• and
• a first alignment layer disposed on the first electrode,
• wherein the first alignment layer comprises a copolymer of cyclobutanedianhydride, a cyclobutanedianhydride derivative, a first diamine, and a second diamine,
• wherein a residual structure of the first diamine in the copolymer includes a group to donate an unshared pair of electrons and a residual structure of the second diamine in the copolymer does not include a group to donate an unshared pair of electrons,
• wherein a repeating unit of the copolymer is a compound represented by Formula O:
• wherein X1, X2, X3 and X4 are independently hydrogen, fluorine, or an organic compound;
• at least one among X1, X2, X3 and X4 is not hydrogen;
• and R1 and R2 are independently hydrogen or an alkyl group;
• and the organic compound is an alkyl group having a carbon number of 1 to 6.