	US 7,611,779 B2
	Organic electroluminescent device
Hiroshi Kanno, Osaka (Japan); Noriyuki Matsusue, Hirakata (Japan); Kaori Saito, Moriguchi (Japan); and Yuji Hamada, Nara (Japan)
Assigned to Sanyo Electric Co., Ltd., Osaka (Japan)
Filed on Mar. 26, 2004, as Appl. No. 10/809,804.
Claims priority of application No. 2003-089415 (JP), filed on Mar. 27, 2003; and application No. 2004-079216 (JP), filed on Mar. 18, 2004.
Prior Publication US 2005/0074630 A1, Apr. 07, 2005
Int. Cl. H01L 51/54 (2006.01)

U.S. Cl. 428—690 [428/917; 313/504; 313/506; 257/E51.044]

4 Claims

1. An organic electroluminescent device comprising in the following order:

a first electrode;

a light emitting layer; and

a second electrode,

said light emitting layer containing two or more different luminescent materials, and at least one of said two or more different luminescent materials being a phosphorescent material, wherein

said at least one phosphorescent material includes a Tris(2-phenylquinoline)iridium, a derivative of said Tris(2-phenylquinoline)iridium or an iridium complex,

said light emitting layer comprises a short wavelength light emitting layer and a long wavelength light emitting layer,

at least one of the peak wavelengths of light emitted by said short wavelength light emitting layer being in a range of 430 nm to 520 nm, and at least one of the peak wavelengths of light emitted by said long wavelength light emitting layer being in a range of 520 nm to 630 nm,

said long wavelength light emitting layer includes a first host material and a first phosphorescent material,

said first electrode is an anode, and said second electrode is a cathode,

said long wavelength light emitting layer and said short wavelength light emitting layer are formed in this order between said anode and said cathode,

said short wavelength light emitting layer further contains a second host material and an assisting dopant, and

said assisting dopant is composed of the same material as said first host material and said assisting dopant is an anthracene derivative or an iridium complex.