Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: 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.

Abstract: The polyimide film of this invention is formed from a polyimide, which is prepared by reacting a diamino compound represented by the general formula (1): ##STR1## wherein X represents a hydrocarbon group having 1 to 20 carbon atoms or a sulfur atom; R represents each independently a halogen atom, a hydrocarbon group having 1 to 6 carbon atoms or a halogen-containing hydrocarbon group having 1 to 6 carbon atoms; a represents each independently an integer of 0 to 4;with a tetracarboxylic dianhydride represented by the general formula (2) ##STR2## wherein Y represents a tetravalent organic group having 2 or more carbon atoms.The polyimide film obtained can be applied favorably to a flexible printed circuit board without adhesion layer, a protective coating for electronic parts and electric wires, or a heat resistant adhesive.

Abstract: A polyimide represented by the general formula (1): ##STR1## wherein Y represents a hydrocarbon group having 4 to 20 carbon atoms or a sulfur atom; each of R.sub.1 to R.sub.4, R.sub.i and R.sub.j represents a halogen atom, a hydrocarbon group having 1 to 6 carbon atoms or a halogen-containing hydrocarbon group having 1 to 6 carbon atoms; each of a, b, c, d, e and f represents an integer of 0 to 4 satisfying a+b.ltoreq.4, c+d.ltoreq.4 and e+f.ltoreq.4; and X represents a tetravalent organic group having 2 or more carbon atoms.