Patent ID: 9269906
Filing Date: 2016-02-23
CPC Classification: H01L

Claim Text:
1. A light-emitting element comprising: a first electrode; a hole-transporting layer over the first electrode; a light-emitting layer over the hole-transporting layer; an electron-transporting layer over the light-emitting layer; a second electrode over the electron-transporting layer; a first layer between the first electrode and the hole-transporting layer; and a second layer between the light-emitting layer and the electron-transporting layer, wherein the first layer comprises a first organic compound having a hole-transporting property and a second organic compound having an electron-transporting property, wherein the second layer comprises a third organic compound having an electron-transporting property and a fourth organic compound having a hole-transporting property, wherein the light-emitting layer consists essentially of a host material and a light-emitting material, wherein the light-emitting material is a first phosphorescent compound, wherein the host material is different from the third organic compound, wherein the fourth organic compound is a second phosphorescent compound different from the first phosphorescent compound, and wherein the hole-transporting layer consists essentially of the first organic compound.