Photosensitive resin composition, solder resist film using said photosensitive resin composition, flexible printed circuit and image display device

A photosensitive resin composition, comprising:

• a photosensitive prepolymer having a carboxyl group and an ethylenically unsaturated group;
• a photopolymerization initiator;
• and
• a thermosetting agent,
• wherein the thermosetting agent is a polycarbodiimide compound represented by the following Formula (1), in which carbodiimide group is protected by an amino group dissociating at a temperature of 80° C. or higher, and the polycarbodiimide compound having a weight average molecular weight of 300 to 3,000 and a carbodiimide equivalent of 150 to 600,
• wherein, in Formula (1),
• R1 and R2 each independently represents a hydrogen atom, a linear or branched alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 6 carbon atoms, R1 and R2 may be same as or different from each other, but both of them are not hydrogen atoms at the same time;
• X1 and X2 each represents —R3—NH—COOR4, R3 being a divalent organic group having at least one aromatic group and R4 being a residue obtained by removing a hydroxy group from an organic group having one hydroxy group, and X1 and X2 being same as or different from each other;
• Y represents —R5—NHCOO—R6—OCOHN—R5—, each R5 being independently a divalent organic group having at least one aromatic group and R6 being a divalent organic group, but not being an ether bond;
• and
• n represents an integer of 1 to 5.