A method of producing a film having excellent external quantum efficiency when used in a light emitting layer of a light emitting device is provided. A method of film production includes preparing an ink containing a specific metal complex, storing the ink for 3 days or more under light shielding, and forming a film by using the stored ink. The total content of metal complexes having a molecular weight larger by 16, 32 or 48 than that of the specific metal complex according to an area percentage value determined by liquid chromatography is 0.6 or less when the content of the specific metal complex is taken as 100.