Photoalignment material, display substrate having an alignment layer formed using the same, and method of manufacturing the display substrate

A display substrate, comprising:

• a gate line disposed on a base substrate;
• a data line crossing the gate line;
• a switching element connected to the gate line and the data line;
• a pixel electrode connected to the switching element;
• and
• an alignment layer disposed on the base substrate, the alignment layer comprising a photosensitive portion, the photosensitive portion represented by the following Chemical Formula 1,
• wherein R1 represents cyclohexane, benzene, chroman, naphthalene, tetrahydropyran, dioxane, or a steroid derivative, each of R2 and R3 represents a single bond, —(CnH2n)—, —(CxH2x)O(CyH2y)—, or —(CaH2a)O(CbH2b)O(CdH2d)—, “n” represents an integer in the range of 1 to 6, each of “x”, “y”, “a”, “b”, and “d” represents 0 or an integer in the range of 1 to 6, x+y is an integer in the range of 1 to 5, a+b+d is an integer in the range of 1 to 6, each hydrogen atom is replaceable with —CH3, —CH2—CH3, —OCH3, —OCH2CH3, —OCH2OCH3, F, or Cl, and each hydrogen atom of —CH3, —CH2—CH3, —OCH3, —OCH2CH3, or —OCH2OCH3 is replaceable with F or Cl,
• wherein the photoalignment polymer is formed by reacting a compound represented by the following Chemical Formula 4 with an acid anhydride,
• wherein “A” represents —(CnH2n)—, “n” represents an integer in the range of 1 to 12, “B” represents a single bond or —(CmH2m)—, “m” represents an integer in the range of 1 to 12, at least one of the (—CH2—)'s in each of “A” and “B” is replaceable with
• and R4 represents a hydrogen atom or an alkyl group having 1 to 12 carbon atoms, and each hydrogen atom of Chemical Formula 4 except the hydrogen atoms of —NH2 is replaceable with F or Cl.