| abstract |
A phosphorescent-emitting layer contains a phosphorescent host and a phosphorescent dopant for providing phosphorescence, and a fluorescent-emitting layer contains a fluorescent host and a fluorescent dopant for providing fluorescence. A charge blocking layer blocks electrons injected into the fluorescent host of the fluorescent-emitting layer from being injected toward the charge blocking layer from the fluorescent-emitting layer, and also injects holes into the fluorescent-emitting layer from the phosphorescent-emitting layer. A triplet energy gap Eg PD of the phosphorescent dopant of the phosphorescent-emitting layer, a triplet energy gap Eg EB of the charge blocking layer and a triplet energy gap Eg FH of the fluorescent host of the fluorescent-emitting layer satisfy the following formula (1). n Eg PD <Eg EB ≦Eg FH (1) |