To provide a method of producing a cured film excellent in patterning property of a contact hole, ITO sputter resistance, and heat resistance transparency, which can be produced at high and stable sensitivity, with slit coating.

The method includes: a process to decrease the temperature of a photosensitive resin composition below 10°C; a process to perform slit coating of the photosensitive resin composition on a substrate; a process to remove solvent from the applied photosensitive resin composition; a process to expose the photosensitive resin composition from which the solvent is removed, with activated light; a process to keep the photosensitive resin composition at room temperature for 45 seconds; a process to develop the photosensitive resin composition with an aqueous developing solution; and a process to thermoset the photosensitive resin composition. The photosensitive resin composition contains: (Component A) a copolymer containing a structural unit including a residue of which acid group is protected by an acid decomposing group, a structural unit including a crosslinking group, and a structural unit including a carboxy group and/or a phenolic hydroxyl group; (Component B) a photoacid generating agent; and (Component C) a solvent.