Patent ID: 7449832
Filing Date: 2008-11-11
Classification: H01L,Y10T

Abstract:
1. An organic electroluminescence device, comprising: an anode; a cathode formed above said anode; a light-emitting layer containing an organic light-emitting material that is formed between said anode and the cathode; a hole-injecting layer on the anode that includes a hole-transporting material and an acceptor; an electron-transporting suppressing stack between the hole-injecting layer and the light-emitting layer; wherein the electron-transporting suppressing stack consists of a plurality of carrier-transporting layers, and forms energy barriers relative to electrons flowing from the light-emitting layer to the hole-injecting layer, and wherein said electron-transporting suppressing stack has arranged a first carrier-transporting layer bordering the anode side of the light-emitting layer and a second carrier-transporting layer bordering the anode side of said first carrier-transporting layer alternating repeatedly in said sequential order, and wherein an electron affinity of the first carrier-transporting layer and an electron affinity of the second carrier-transporting layer have a relationship in an equation (1) represented as where in the equation (1) E