COMPOSITION AND LIGHT-EMITTING ELEMENT USING SAME

摘要

Provided is a composition useful in the manufacture of a light-emitting element having a low drive voltage. The composition comprises a phosphorescent compound represented by formula (1) and a phosphorescent compound represented by formula (2). (In formula (1), M1 represents an iridium atom or the like; n1 represents an integer equal to or greater than 1; n2 is an integer equal to or greater than 0; E1 and E2 represent a carbon atom or the like; ring R1 represents a five-membered aromatic heterocycle; ring R2 represents an aromatic hydrocarbon ring or the like; and A1-G1-A2 represents an anionic bidentate ligand; provided that at least one ring selected from the group consisting of ring R1 and ring R2 has a specific aryl group.) (In formula (2), M2 represents an iridium atom or the like; n3 is an integer equal to or greater than 1; n4 represents an integer equal to or greater than 0; E4 represents a carbon atom or the like; ring L1 represents a six-membered aromatic heterocycle; ring L2 represents an aromatic hydrocarbon ring or the like; and A3-G2-A4 represents an anionic bidentate ligand; provided that at least one ring selected from the group consisting of ring L1 and ring L2 has a specific aryl group.)