Light-emitting device
View Patent ↗A light-emitting device which can effectively be utilized as a surface light source for a full-color display, a back light or an illumination light source, or as a light source array in a printer, which shows an excellent light-emitting efficiency and light-emitting luminance, and which is particularly excellent as a white light source showing an excellent light-emitting efficiency and light-emitting luminance. The light-emitting device comprises a substrate having provided thereon at least an anode, an organic compound layer including a light-emitting layer, and a cathode, in which the light-emitting layer contains two or more different kinds of light-emitting materials, with at least one of the light-emitting materials being an orthometallated complex.
1. A light-emitting device comprising at least an anode, an organic compound layer containing a light-emitting layer, and a cathode which are provided on a substrate,
wherein the light-emitting layer is disposed between the anode and the cathode, and comprises a red light-emitting material having a light-emitting wavelength peak of from 580 to 670 nm, a green light-emitting material having a light-emitting wavelength peak of from 500 to 570 nm, and a blue light-emitting material having a light-emitting wavelength peak of from 400 to 500 nm, and
wherein the green light-emitting material comprises at least one green light-emitting material which is an orthometallated complex;
wherein the red light-emitting material comprises at least one red light-emitting material which is an orthometallated complex;
wherein the metal forming the complex for the at least one green light-emitting material which is an orthometallated complex is iridium or platinum;
wherein the metal forming the complex for the at least one red light-emitting material which is an orthometallated complex is iridium;
wherein
(1) the blue, green and red light-emitting materials are contained in the same light-emitting layer, or
(2) the light-emitting layer comprises at least two different light-emitting layers in physical contact with each other, each containing at least one of the blue, green or red light-emitting materials.
2. The light-emitting device as claimed in claim 1 , wherein the metal forming the complex for the at least one green light-emitting material which is an orthometallated complex is iridium.
3. The light-emitting device as claimed in claim 2 , wherein the ligand forming the complex for the at least one green light-emitting material which is an orthometallated complex is a 2-phenylpyridine derivative.
4. The light-emitting device as claimed in claim 1 , wherein the ligand forming the complex for the at least one green light-emitting material which is an orthometallated complex is a 2-phenylpyridine derivative.
5. The light-emitting device as claimed in claim 1 , wherein the ligand forming the complex for the at least one red light-emitting material which is an orthometallated complex is a 2-phenylquinoline derivative.
6. The light-emitting device as claimed in claim 1 , wherein the blue, green and red light-emitting materials are contained in the same light-emitting layer.
7. The light-emitting device as claimed in claim 1 , which emits a white light.
8. The light-emitting device as claimed in claim 1 , wherein the light-emitting layer comprises at least two different light-emitting layers in physical contact with each other, each containing at least one of the blue, green or red light-emitting materials.
9. The light-emitting device as claimed in claim 1 , wherein the light-emitting layer comprises at least two different light-emitting layers in physical contact with each other, each containing at least one of the green or red light-emitting materials.
10. The light-emitting device as claimed in claim 1 , wherein the light-emitting layer comprises at least three different light-emitting layers, each containing only one of the blue, green or red light-emitting materials, with the light-emitting layer containing the green light-emitting material being in physical contact with the light-emitting layer containing the red light-emitting material.