Organic electroluminescence device

Patent metadata

Field	Value
Publication number	US-9324950-B2
Application number	US-201113302063-A
Country	US
Kind code	B2
Filing date	Nov 22, 2011
Priority date	Nov 22, 2010
Publication date	Apr 26, 2016
Grant date	Apr 26, 2016

Abstract

An organic electroluminescence device that includes an anode, an emitting layer that includes a host and a fluorescent dopant, an electron transporting zone, a cathode, a blocking layer adjacent to the emitting layer in the electron transporting zone where the blocking layer includes an aromatic heterocyclic derivative with an azine ring and where the triplet energy E T b (eV) of the aromatic heterocyclic derivative is larger than a triplet energy E T h (eV) of the host.

First claim

What is claimed is:

1. An organic electroluminescence device, comprising in sequential order an anode, an emitting layer, an electron transporting zone, and a cathode, wherein
the emitting layer comprises a host and a fluorescent dopant,
a triplet energy E T d (eV) of the fluorescent dopant is larger than a triplet energy E T h (eV) of the host,
the fluorescent dopant is a pyrene derivative,
a blocking layer is adjacent to the emitting layer in the electron transporting zone,
the blocking layer comprises an aromatic heterocyclic derivative,
a triplet energy E T b (eV) of the aromatic heterocyclic derivative is larger than a triplet energy E T h (eV) of the host, and
the aromatic heterocyclic derivative is represented by formula (BL-21):

wherein HAr independently represents a substituted or unsubstituted 1-pyrrolyl group, 2-pyrrolyl group, 3-pyrrolyl group, pyrazinyl group, 2-pyridinyl group, 3-pyridinyl group, 4-pyridinyl group, 1-indolyl group, 2-indolyl group, 3-indolyl group, 4-indolyl group, 5-indolyl group, 6-indolyl group, 7-indolyl group, 1-isoindolyl group, 2-isoindolyl group, 3-isoindolyl group, 4-isoindolyl group, 5-isoindolyl group, 6-isoindolyl group, 7-isoindolyl group, 2-furyl group, 3-furyl group, 2-benzofuranyl group, 3-benzofuranyl group, 4-benzofuranyl group, 5-benzofuranyl group, 6-benzofuranyl group, 7-benzofuranyl group, 1-isobenzofuranyl group, 3-isobenzofuranyl group, 4-isobenzofuranyl group, 5-isobenzofuranyl group, 6-isobenzofuranyl group, 7-isobenzofuranyl group, 1-dibenzofuranyl group, 2-dibenzofuranyl group, 3-dibenzofuranyl group, 4-dibenzofuranyl group, 1-dibenzothiophenyl group, 2-dibenzothiophenyl group, 3-dibenzothiophenyl group, 4-dibenzothiophenyl group, 2-quinoxalinyl group, 5-quinoxalinyl group, 6-quinoxalinyl group, 1-carbazolyl group, 2-carbazolyl group, 3-carbazolyl group, 4-carbazolyl group, 9-carbazolyl group, 1-phenanthridinyl group, 2-phenanthridinyl group, 3-phenanthridinyl group, 4-phenanthridinyl group, 6-phenanthridinyl group, 7-phenanthridinyl group, 8-phenanthridinyl group, 9-phenanthridinyl group, 10-phenanthridinyl group, 1-acridinyl group, 2-acridinyl group, 3-acridinyl group, 4-acridinyl group, 9-acridinyl group, 1,7-phenanthroline-2-yl group, 1,7-phenanthroline-3-yl group, 1,7-phenanthroline-4-yl group, 1,7-phenanthroline-5-yl group, 1,7-phenanthroline-6-yl group, 1,7-phenanthroline-8-yl group, 1,7-phenanthroline-9-yl group, 1,7-phenanthroline-10-yl group, 1,8-phenanthroline-2-yl group, 1,8-phenanthroline-3-yl group, 1,8-phenanthroline-4-yl group, 1,8-phenanthroline-5-yl group, 1,8-phenanthroline-6-yl group, 1,8-phenanthroline-7-yl group, 1,8-phenanthroline-9-yl group, 1,8-phenanthroline-10-yl group, 1,9-phenanthroline-2-yl group, 1,9-phenanthroline-3-yl group, 1,9-phenanthroline-4-yl group, 1,9-phenanthroline-5-yl group, 1,9-phenanthroline-6-yl group, 1,9-phenanthroline-7-yl group, 1,9-phenanthroline-8-yl group, 1,9-phenanthroline-10-yl group, 1,10-phenanthroline-2-yl group, 1,10-phenanthroline-3-yl group, 1,10-phenanthroline-4-yl group, 1,10-phenanthroline-5-yl group, 2,9-phenanthroline-1-yl group, 2,9-phenanthroline-3-yl group, 2,9-phenanthroline-4-yl group, 2,9-phenanthroline-5-yl group, 2,9-phenanthroline-6-yl group, 2,9-phenanthroline-7-yl group, 2,9-phenanthroline-8-yl group, 2,9-phenanthroline-10-yl group, 2,8-phenanthroline-1-yl group, 2,8-phenanthroline-3-yl group, 2,8-phenanthroline-4-yl group, 2,8-phenanthroline-5-yl group, 2,8-phenanthroline-6-yl group, 2,8-phenanthroline-7-yl group, 2,8-phenanthroline-9-yl group, 2,8-phenanthroline-10-yl group, 2,7-phenanthroline-1-yl group, 2,7-phenanthroline-3-yl group, 2,7-phenanthroline-4-yl group, 2,7-phenanthroline-5-yl group, 2,7-phenanthroline-6-yl group, 2,7-phenanthroline-8-yl group, 2,7-phenanthroline-9-yl group, 2,7-phenanthroline-10-yl group, 1-phenazinyl group, 2-phenazinyl group, 1-phenothiazinyl group, 2-phenothiazinyl group, 3-phenothiazinyl group, 4-phenothiazinyl group, 10-phenothiazinyl group, 1-phenoxazinyl group, 2-phenoxazinyl group, 3-phenoxazinyl group, 4-phenoxazinyl group, 10-phenoxazinyl group, 2-oxazolyl group, 4-oxazolyl group, 5-oxazolyl group, 2-oxadiazolyl group, 5-oxadiazolyl group, 3-furazanyl group, 2-thienyl group, 3-thienyl group, 2-methylpyrrole-1-yl group, 2-methylpyrrole-3-yl group, 2-methylpyrrole-4-yl group, 2-methylpyrrole-5-yl group, 3-methylpyrrole-1-yl group, 3-methylpyrrole-2-yl group, 3-methylpyrrole-4-yl group, 3-methylpyrrole-5-yl group, 2-t-butylpyrrole-4-yl group, 3-(2-phenylpropyl)pyrrole-1-yl group, 2-methyl-1-indolyl group, 4-methyl-1-indolyl group, 2-methyl-3-indolyl group, 4-methyl-3-indolyl group, 2-t-butyl-1-indolyl group, 4-t-butyl-1-indolyl group, 2-t-butyl-3-indolyl group, or 4-t-butyl-3-indolyl group, wherein if a plurality of HAr groups are present, the plurality of HAr groups may be the same or different;
L represents (i) a single bond, (ii) a divalent to tetravalent residue of a substituted or unsubstituted aromatic hydrocarbon ring having 6 to 30 ring carbon atoms, (iii) a divalent to tetravalent residue of a substituted or unsubstituted heterocyclic ring having 5 to 30 ring atoms, (iv) a divalent to tetravalent residue of a group in which two rings selected from the aromatic hydrocarbon ring and the heterocyclic ring are combined through a single bond; or (v) a divalent to tetravalent residue of a group in which three rings selected from the aromatic hydrocarbon ring and the heterocyclic ring are combined through single bonds;
a is an integer of 1 to 3;
b is an integer of 1 to 3; and
Az represents an azine ring represented by formula (BL-21-1):

wherein at least two X's are N and the rest of X is C(Ar);
Ar is a hydrogen atom, substituted or unsubstituted alkyl group having 1 to 20 carbon atoms, substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms or substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms; and
at least one of Ar 1 , Ar 2 and Ar 3 is a single bond bonded to L in the formula (BL-21) and the rest of Ar 1 , Ar 2 , and Ar 3 not bonded to L in the formula (BL-21) is
a hydrogen atom,
a substituted or unsubstituted alkyl group having 1 to 20 carbon atoms,
a substituted or unsubstituted aryl group having 6 to 30 ring carbon atoms, or
a substituted or unsubstituted heterocyclic group having 5 to 30 ring atoms.

2. The organic electroluminescence device according to claim 1 , wherein
an electron mobility of the aromatic heterocyclic derivative is at least 10 −6 cm 2 /Vs in an electric field intensity of 0.04 MV/cm to 0.5 MV/cm.

3. The organic electroluminescence device according to claim 1 , wherein
the triplet energy E T b (eV) of the aromatic heterocyclic derivative and the triplet energy E T h (eV) of the host satisfy a relationship of E T h +0.2<E T b .

4. The organic electroluminescence device according to claim 1 , wherein
the electron transporting zone comprises an electron injecting layer.

5. The organic electroluminescence device according to claim 4 , wherein
the electron injecting layer comprises a material that has an electron mobility of at least 10 −6 cm 2 /Vs in an electric field intensity of 0.04 MV/cm to 0.5 MV/cm.

6. The organic electroluminescence device according to claim 4 , wherein the electron injecting layer and the blocking layer are formed of the same material.

7. The organic electroluminescence device according to claim 4 , wherein the electron injecting layer and the blocking layer are formed of the

Assignees

• Kawamura Yuichiro
• Saito Hiroyuki
• Kuma Hitoshi
• Kawamura Masahiro
• Jinde Yukitoshi
• Ito Hirokatsu
• Sado Takayasu
• Mizutani Sayaka
• Idemitsu Kosan Co

Inventors

• Kawamura Yuichiro
• Saito Hiroyuki
• Kuma Hitoshi
• Kawamura Masahiro
• Jinde Yukitoshi
• Ito Hirokatsu
• Sado Takayasu
• Mizutani Sayaka

Classifications

• H10K85/6572

  comprising only nitrogen in the heteroaromatic polycondensed ring system, e.g. phenanthroline or carbazole · CPC title

• C09K11/06 Primary

  containing organic luminescent materials · CPC title

• H01L51/0073

  Electricity · mapped topic

• H01L51/0068

  Electricity · mapped topic

• H01L51/0072

  Electricity · mapped topic