The purpose of the present invention is to provide a, polyimide film having high transparency and improved bending resistance against multiple times of bending, and a varnish capable of providing such a polyimide film. The varnish according to the present invention contains a polymer (α) and a solvent (β). The polymer (α) is polyimide or a polyimide precursor. The varnish further contains a typical metal element having an atomic weight of 26-201 except alkali metals and alkaline earth metals, or at least one metal element among transition metal elements having an atomic weight of 26-201 or less. At least one of the metal elements contained in the varnish is present in an amount of 0.05-500 ppm relative to the polymer (α).