| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an organic electroluminescent element which has greatly improved initial durability over elements using conventional materials. <P>SOLUTION: The organic electroluminescent element includes a pair of electrodes and a luminescent layer between the electrodes on a substrate. The luminescent layer contains a phosphorescent metal complex A, and contains a prescribed amount or none of a structural isomer group B which, although expressed by the same chemical formula as the phosphorescent metal complex A, differs in ligand configuration three-dimensionally. Furthermore, the host material of the luminescent layer is such that a ratio of the number of nitrogen atoms included in its molecular structure which are of an N-phenyl carbazole structure expressed by the formula (II) below to the total number of carbon atoms included in the whole molecule of the host material, or an N/C ratio, is limited within a prescribed range. <P>COPYRIGHT: (C)2013,JPO&INPIT |
