Photoalignment agent, photoalignment film, liquid crystal display device, and method of manufacturing 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 obtained from at least one of cyclobutane dianhydride (CBDA) and a cyclobutane dianhydride derivative, and a diamine;
• and
• a cross-linking agent comprising an alkylene group —CnH2n—, n being a natural number.

A method of manufacturing a liquid crystal display, the method comprising:

• forming a thin-film transistor on a first substrate;
• forming a passivation layer on the thin-film transistor;
• forming a first electrode and a second electrode on the passivation layer;
• disposing an insulating layer between the first electrode and the second electrode;
• coating a photoalignment agent on the first electrode or the second electrode;
• baking the photoalignment agent;
• and
• forming a first alignment layer by irradiating polarized light to the photoalignment agent,
• wherein the photoalignment agent comprises:
• a copolymer formed from at least one of cyclobutane dianhydride (CBDA) and a cyclobutane dianhydride derivative, and a diamine;
• and
• a cross-linking agent comprising an alkylene group —CnH2n—, n being a natural number.