US 7,507,485 B2
Organic electroluminescent device
Hyoung Yun Oh, Seoul (Korea, Republic of); Sung Koo Lee, Kyonggi-do (Korea, Republic of); Chun Gun Park, Seoul (Korea, Republic of); Jeong Dae Seo, Kyonggi-do (Korea, Republic of); and Myung Seop Kim, Seoul (Korea, Republic of)
Assigned to LG Display Co., Ltd., Seoul (Korea, Republic of)
Filed on Sep. 26, 2002, as Appl. No. 10/254,999.
Claims priority of application No. P2001-67267 (KR), filed on Oct. 30, 2001.
Prior Publication US 2003/0118866 A1, Jun. 26, 2003
Int. Cl. H01L 51/50 (2006.01)
U.S. Cl. 428—690  [428/917; 313/504; 313/506] 4 Claims
OG exemplary drawing
 
1. An organic electroluminescent device comprising:
a first electrode;
a second electrode; and
a light-emitting layer having a guest material of a red luminescent material and first and second host materials formed between the first and second electrodes;
wherein the first host material is an aromatic compound having one of the following structural formula;

OG Complex Work Unit Drawing
the second host material is a compound Alq3 which has the following structural formula;

OG Complex Work Unit Drawing
and the guest material is a DCM Derivative which has the following structural formula;

OG Complex Work Unit Drawing
wherein the light emitting layer with the guest material and the first and second host materials enhances red luminescence efficiency of the device and has similar CIE coordinates of a red color in comparison with a red light emitting layer comprising the second host material alone with the guest material, wherein the first host material alone has a first PL peak value at a first wavelength, the second host material alone has a second PL luminescent peak value at a second wavelength, and the first and second host materials together have a third PL peak value at a third wavelength band between the first and second wavelengths.