| 摘要 |
A first aspect of the invention is an organic electroluminescent device that includes a plurality of organic compound layers between a pair of electrodes. The plurality of organic compound layers include a luminescent layer and two or more hole-transporting layers. The hole-transporting layers include a layer adjacent to the luminescent layer. The luminescent layer contains a host material and a luminescent material. The luminescent material is a metal complex containing a tri- or higher-dentate ligand. When the ionization potential of the luminescent layer is designated as Ip<SUB>0</SUB>, the ionization potential of the hole-transporting layer adjacent to the luminescent layer among the hole-transporting layers is designated as Ip<SUB>1</SUB>, and the ionization potential of the n-th hole-transporting layer from the luminescent layer among the hole-transporting layers is designated as IP<SUB>n</SUB>, these values satisfy the relationship represented by the following formula (1). In formula (1) n is an integer of 2 or more. <?in-line-formulae description="In-line Formulae" end="lead"?>Ip<SUB>0</SUB>>Ip<SUB>1</SUB>>Ip<SUB>2</SUB>> . . . >Ip<SUB>n-1</SUB>>Ip<SUB>n</SUB> formula (1) <?in-line-formulae description="In-line Formulae" end="tail"?>
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