Patent ID: 8420228

Claim:
A white light-emitting organic electroluminescent (EL) device comprising: first and second organic light emitting layers respectively interposed between an anode and a cathode, wherein the first organic light emitting layer is red light emitting layer formed of DCJBT-doped Alq3, the second organic light emitting layer is blue light emitting layer formed of DPVBi, and the white-light emitting organic electroluminescent device realizes white light emission via combination of blue and red lights; a first buffer layer arranged between an intermediate layer and the first light-emitting layer to improve carrier blocking performance; a second buffer layer arranged between the intermediate layer and the second light-emitting layer to improve carrier blocking performance, wherein the first and second buffer layers arranged between the light-emitting layers; and the intermediate layers having carrier blocking capability respectively interposed between the first and second buffer layers; wherein the intermediate layers include a hole blocking functioning material and an electron blocking functioning material; wherein an absolute value of highest occupied molecular orbital (HOMO) of the hole blocking functioning material is 5.2 eV or higher and an absolute value of the lowest occupied molecular orbital of the electron blocking functioning material is 3.3 eV or below; wherein the proportion of the hole blocking functioning material and the electron blocking functioning material in the intermediate layer is determined such that holes and electrons injected into the organic light emitting layers can be adjusted to optimize luminous efficiency of the organic electroluminescent (EL) device; wherein the hole blocking functioning material is selected from CF—X, CF—Y and lanthanide compounds.