Patent ID: 8758903

Claim:
An organic electroluminescent element comprising a substrate having thereon an electrode and one or more organic layers, wherein one of the organic layers is a light emitting layer which incorporates a phosphorescent compound represented by Formula (1) and a host compound, and the light emitting layer has a film surface density of 1.10-1.25 g/cm 3 : wherein R 1 represents a substituent; Z represents a group of non-metallic atoms necessary to form a 5- to 7-membered ring; n1 represents an integer of 0 -5; B 1 -B 5 each represents the following set (i) or set (ii): set (i) B1 and B3 are a nitrogen atom, and B2, B4, and B5 are a carbon atom, set (ii) B2 and B5 are a nitrogen atom, and B1, B3, and B4 are a carbon atom; M 1 represents a metal in Groups 8-10 of a periodic table; X 1 and X 2 each represents a carbon atom, a nitrogen atom, or an oxygen atom; L1 represents a group of atoms which forms a bidentate ligand together with X 1 and X 2 ; m1 represents an integer of 1-3; and m2 represents an integer of 0-2, provided that a sum of m1 and m2 is an integer of 2 or 3.