Patent ID: 7727640
Filing Date: 2010-06-01
Classification: H01L,Y10S,Y10T

Abstract:
1. An organic electroluminescent element comprising, between an anode and a cathode, at least a luminescent layer and an adjacent layer that is adjacent to the cathode side of the luminescent layer, wherein said adjacent layer is formed directly on the luminescent layer, and wherein the luminescent layer contains a phosphorescent material and a host material, the adjacent layer contains an electron transport material and a hole transport material, said luminescent layer does not contain said electron transport material and said hole transport material, the thickness of the adjacent layer is 1 nm to 12 nm, and the electron affinity Ea (HT) of the hole transport material and the electron affinity Ea (ET) of the electron transport material satisfy the relation of 1 eV≦Ea (ET)−Ea (HT)≦2.8 eV.