Diamine compound, and polyimide precursor and polyimide film using same

A diamine compound of the following formula 1:

• In the formula 1,
• Z is —NH—,
• R1 to R4 are each independently hydrogen, deuterium, a halogen atom, a cyano group, a substituted or unsubstituted alkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted haloalkyl group having 1 to 30 carbon atoms, a substituted or unsubstituted alkylsilyl group having 1 to 30 carbon atoms, a substituted or unsubstituted arylsilyl group having 6 to 30 carbon atoms, a substituted or unsubstituted alkylamino group having 1 to 30 carbon atoms, a substituted or unsubstituted arylamino group having 6 to 30 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 30 carbon atoms, a substituted or unsubstituted alkylthio group having 1 to 30 carbon atoms, a substituted or unsubstituted arylthiol group having 6 to 30 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, a substituted or unsubstituted aralkyl group having 6 to 30 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 30 carbon atoms, an amide group, a substituted or unsubstituted cycloalkyloxy group having 3 to 30 carbon atoms, a substituted or unsubstituted cycloalkylthio group having 1 to 30 carbon atoms, an ester group, an azide group, or a substituted or unsubstituted (3-30 membered) heteroaryl group comprising at least one selected from B, N, O, S, P (═O), Si and P,
• a, b, c and d are each an integer of 0 to 4, and when a, b, c and d are each an integer of 2 to 4, each of a, b, c and d is the same or different, and
• each of the two amino group substituents is substituted at a meta-position or para-position of each of the benzene rings with respect to the carbonyl group in each of the benzene rings.