JPH10340783A - Organic electroluminescent element - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic electroluminescent element with high luminous efficiency and emitting light with high brightness by interposing at least one layer containing at least one kind of benzo [1,2-k: 4,5-k'] difluoranthene derivative between a pair of electrodes. SOLUTION: A benzo [1,2-k: 4,5-k'] difluoranthene derivative used is preferably a compound represented by the formula. In the formula, X1 -X18 represent hydrogen atom, halogen atom, a straight chain, branched, or cyclic alkyl group, a straight chain, branched, or cyclic alkoxy group, or a substituted, or non- substituted aryl group. X1 -X18 are preferably a hydrogen atom, an alkyl group having 1-6C, or a carbon cyclic aromatic group having 6-10C. The compound can be used in a hole injection transporting component, a luminescent component, or an electron injection transporting component, and can be especially preferably used in the luminescent component.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to an organic electroluminescent device.

[0002]

2. Description of the Related Art Conventionally, an inorganic electroluminescent element has been used as a panel-type light source such as a backlight. However, driving the light emitting element requires a high AC voltage. Recently, an organic electroluminescent device (organic electroluminescent device: organic EL device) using an organic material as a light emitting material has been developed [Appl. Phys. Lett., 51 ,
913 (1987)]. The organic electroluminescent element has a structure in which a thin film containing a fluorescent organic compound is sandwiched between an anode and a cathode,
An exciton is generated by injecting electrons and holes into the thin film and recombining them, and emits light using light emitted when the exciton is deactivated. is there. The organic electroluminescent element can emit light at a low DC voltage of about several volts to several tens of volts, and various colors (for example, red, blue, and green) can be obtained by selecting the type of the fluorescent organic compound. ) Is possible. Organic electroluminescent devices having such features include various light emitting devices,
Application to display elements and the like is expected. However,
Generally, the light emission luminance is low and is not practically sufficient.

As a method for improving light emission luminance, an organic electroluminescent device using, for example, tris (8-quinolinolato) aluminum as a host compound, a coumarin derivative, or a pyran derivative as a guest compound (dopant) has been proposed as a light emitting layer. (J. Appl. Phys., 65 , 3610
(1989)]. As the light emitting layer, for example, bis (2-
An organic electroluminescent device using methyl-8-quinolinolate) (4-phenylphenolate) aluminum as a host compound and an acridone derivative (for example, N-methyl-2-methoxyacridone) as a guest compound has been proposed. JP-A-8-67873). However,
It is hard to say that these light-emitting elements also have sufficient light emission luminance. At present, an organic electroluminescent device that emits light with higher luminance is desired.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide an organic electroluminescent device which is excellent in luminous efficiency and emits light with high luminance.

[0005]

Means for Solving the Problems The present inventors have made intensive studies on the organic electroluminescent device, and as a result, completed the present invention. That is, the present invention provides an organic electroluminescent device comprising at least one layer containing at least one benzo [1,2-k: 4,5-k '] difluoranthene derivative between a pair of electrodes, The organic electroluminescent device according to the above, wherein the layer containing the benzo [1,2-k: 4,5-k '] difluoranthene derivative is a light-emitting layer. Benzo [1,2-k: 4,5-k' The organic electroluminescent device according to the above or the above, wherein the layer containing the difluoranthene derivative further contains a light-emitting organometallic complex, any one of the above-mentioned items having a hole injection transport layer between a pair of electrodes. The organic electroluminescent device according to any one of the above-mentioned, further comprising an electron injecting and transporting layer between a pair of electrodes, benzo [1,2-k: 4,5-k ′. Wherein the difluoranthene derivative is a compound represented by the general formula (1)
The organic electroluminescent device according to any one of the above.

[0006]

Embedded image (Wherein, X _{1 to} X ₁₈ are a hydrogen atom, a halogen atom, a straight chain,
Represents a branched or cyclic alkyl group, a straight-chain, branched or cyclic alkoxy group, or a substituted or unsubstituted aryl group)

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail. The organic electroluminescent device of the present invention, between a pair of electrodes,
It comprises at least one layer containing at least one benzo [1,2-k: 4,5-k '] difluoranthene derivative. The benzo [1,2-k: 4,5-k ′] difluoranthene derivative (hereinafter, abbreviated as compound A according to the present invention) according to the present invention is preferably represented by the general formula (1). Compound.

In the compound represented by the general formula (1),
X _{1 to} X ₁₈ represent a hydrogen atom, a halogen atom, a linear, branched or cyclic alkyl group, a linear, branched or cyclic alkoxy group, or a substituted or unsubstituted aryl group.
The aryl group represents, for example, a carbocyclic aromatic group such as a phenyl group and a naphthyl group, and a heterocyclic aromatic group such as a furyl group, a thienyl group and a pyridyl group. Preferably, X _{1 to} X ₁₈ are a hydrogen atom; a halogen atom (eg, a fluorine atom, a chlorine atom, a bromine atom);
6 linear, branched or cyclic alkyl groups (e.g., methyl, ethyl, n-propyl, isopropyl, n
-Butyl group, isobutyl group, sec-butyl group, tert-butyl group, n-pentyl group, isopentyl group, neopentyl group, tert-pentyl group, cyclopentyl group, n-hexyl group, 3,3-dimethylbutyl group, cyclohexyl Group, n-heptyl group, cyclohexylmethyl group, n-octyl group, tert-octyl group, 2-ethylhexyl group,
n-nonyl group, n-decyl group, n-dodecyl group, n-tetradecyl group, n-hexadecyl group, etc.);
Sixteen linear, branched or cyclic alkoxy groups (for example,
Methoxy group, ethoxy group, n-propoxy group, isopropoxy group, n-butoxy group, isobutoxy group, sec-butoxy group, n-pentyloxy group, neopentyloxy group, cyclopentyloxy group, n-hexyloxy group,
3,3-dimethylbutyloxy group, cyclohexyloxy group, n-heptyloxy group, n-octyloxy group,
2-ethylhexyloxy group, n-nonyloxy group, n
-Decyloxy group, n-dodecyloxy group, n-tetradecyloxy group, n-hexadecyloxy group and the like, or a substituted or unsubstituted aryl group having 4 to 16 carbon atoms (for example, phenyl group;

A 2-methylphenyl group, a 3-methylphenyl group, a 4-methylphenyl group, a 4-ethylphenyl group,
4-n-propylphenyl group, 4-isopropylphenyl group, 4-n-butylphenyl group, 4-tert-butylphenyl group, 4-isopentylphenyl group, 4-tert-pentylphenyl group, 4-n-hexyl Phenyl group, 4-
Cyclohexylphenyl group, 4-n-octylphenyl group, 4-n-decylphenyl group, 2,3-dimethylphenyl group, 2,4-dimethylphenyl group, 2,5-dimethylphenyl group, 3,4-dimethylphenyl Group, 5-indanyl group, 1,2,3,4-tetrahydro-5-naphthyl group, 1,2,3,4-tetrahydro-6-naphthyl group, 2-methoxyphenyl group, 3-methoxyphenyl group, -Methoxyphenyl group, 3-ethoxyphenyl group, 4-ethoxyphenyl group, 4-n-propoxyphenyl group, 4-isopropoxyphenyl group, 4-n-butoxyphenyl group, 4-n-pentyloxyphenyl group,
4-n-hexyloxyphenyl group, 4-cyclohexyloxyphenyl group, 4-n-heptyloxyphenyl group, 4-n-octyloxyphenyl group, 4-n-decyloxyphenyl group, 2,3-dimethoxyphenyl group ,
2,5-dimethoxyphenyl group, 3,4-dimethoxyphenyl group, 2-methoxy-5-methylphenyl group, 3-
Methyl-4-methoxyphenyl group, 2-fluorophenyl group, 3-fluorophenyl group, 4-fluorophenyl group, 2-chlorophenyl group, 3-chlorophenyl group, 4
-Chlorophenyl group, 4-bromophenyl group, 4-trifluoromethylphenyl group, 3,4-dichlorophenyl group, 2-methyl-4-chlorophenyl group, 2-chloro-
4-methylphenyl group, 3-chloro-4-methylphenyl group, 2-chloro-4-methoxyphenyl group, 4-phenylphenyl group, 3-phenylphenyl group, 4- (4 ′
-Methylphenyl) phenyl group, 4- (4'-methoxyphenyl) phenyl group, 1-naphthyl group, 2-naphthyl group, 4-ethoxy-1-naphthyl group, 6-methoxy-2
-Naphthyl group, 7-ethoxy-2-naphthyl group, 2-furyl group, 2-thienyl group, 3-thienyl group, 2-pyridyl group, 3-pyridyl group, 4-pyridyl group, etc.)
More preferably, it is a hydrogen atom, a fluorine atom, a chlorine atom, an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, or an aryl group having 6 to 10 carbon atoms. It is a C1-C6 alkyl group or a C6-C10 carbocyclic aromatic group.

The compound A according to the present invention includes a compound represented by the general formula (1) wherein X _{1 to} X ₁₈ are hydrogen atoms,
A compound in which X ₈ and X ₁₇ are an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 10 carbon atoms, and the others are hydrogen atoms; X ₇ , X ₉ , X ₁₆ and X _{18 each} have 1 to 6 carbon atoms; 6
And a compound having an alkyl group or an aryl group having 6 to 10 carbon atoms, and the others being hydrogen atoms.

Specific examples of the compound A according to the present invention include:
For example, the following compounds can be mentioned, but the present invention is not limited thereto. -Exemplified compound number Benzo [1,2-k: 4,5-k '] difluoranthene 2. 2. 3-ethylbenzo [1,2-k: 4,5-k '] difluoranthene 8-methylbenzo [1,2-k: 4,5-k '] difluoranthene 8-n-octylbenzo [1,2-k: 4,5-k '] difluoranthene 5. 3-methoxybenzo [1,2-k: 4,5-k '] difluoranthene 6. 3-chlorobenzo [1,2-k: 4,5-k '] difluoranthene 8,17-dimethylbenzo [1,2-k: 4,5-k '] difluoranthene 8. 3,12-diethylbenzo [1,2-k: 4,5-k '] difluoranthene 8,17-diethylbenzo [1,2-k: 4,5-k '] difluoranthene 8,17-di-n-propylbenzo [1,2-k: 4,5-k '] difluoranthene

[0012] 11. 8,17-di-n-butylbenzo [1,2-k: 4,5-k '] difluoranthene 8,17-di-tert-butylbenzo [1,2-k: 4,5-k '] difluoranthene 13. 8,17-di-neopentylbenzo [1,2-k: 4,5-k '] difluoranthene 8,17-di-n-hexylbenzo [1,2-k: 4,5-k '] difluoranthene 8,17-di-n-octylbenzo [1,2-k: 4,5-k '] difluoranthene 8,17-di-n-dodecylbenzo [1,2-k: 4,5-k '] difluoranthene 7,9,16,18-tetraethylbenzo [1,2-k: 4,5-k '] difluorolanthene 7,9,16,18-tetra-n-butylbenzo [1,2-k: 4,5-k '] difluoranthene 7,9,16,18-tetra-n-hexylbenzo [1,2-k: 4,5-k '] difluoranthene 3,13, -diethoxybenzo [1,2-k: 4,5-k '] difluoranthene 8,17-dimethoxybenzo [1,2-k: 4,5-k '] difluoranthene 8,17-di-n-butoxybenzo [1,2-k: 4,5-k '] difluoranthene 8,17-di-n-hexyloxybenzo [1,2-k: 4,5-k '] difluoranthene 3,12-dichlorobenzo [1,2-k: 4,5-k '] difluoranthene 25. 8,17-difluorobenzo [1,2-k: 4,5-k '] difluoranthene

[0013] 26. 8-n-butyl-17-phenylbenzo [1,2-k: 4,5-k '] difluoranthene 27. 8,17-diphenylbenzo [1,2-k: 4,5-k '] difluoranthene 8,17-di (4'-methylphenyl) benzo [1,2-k: 4,5-k '] difluoranthene 29. 8,17-di (4'-ethylphenyl) benzo [1,2-k: 4,5-k '] difluoranthene 30. 8,17-di (4'-tert-butylphenyl) benzo [1,2-k: 4,5-k '] difluoranthene 31. 8,17-di (4'-n-octylphenyl) benzo [1,2-k: 4,5-k '] difluoranthene 32. 8,17-di (4'-methoxyphenyl) benzo [1,2-k: 4,5-k '] difluoranthene 8,17-di (4'-n-butoxyphenyl) benzo [1,2-k: 4,5-k '] difluoranthene 34. 8,17-di (4'-n-hexyloxyphenyl) benzo [1,2-k: 4,5-k '] difluoranthene 35. 8,17-di (4'-n-decyloxyphenyl) benzo [1,2-k: 4,5-k '] difluoranthene 8,17-di (4'-fluorophenyl) benzo [1,2-k: 4,5-k '] difluoranthene 8,17-di (3'-fluorophenyl) benzo [1,2-k: 4,5-k '] difluoranthene 8,17-di (4'-chlorophenyl) benzo [1,2-k: 4,5-k '] difluoranthene 39. 8,17-di (2'-naphthyl) benzo [1,2-k: 4,5-k '] difluoranthene

[0014] 40. 8-phenyl-17- (3'-methylphenyl) benzo [1,2-k: 4,5-k '] difluoranthene 41. 8-phenyl-17- (3'-ethoxyphenyl) benzo [1,2-k: 4,5-k '] difluoranthene 42. 7,9,16,18-tetraphenylbenzo [1,2-k: 4,5-k '] difluoranthene 43. 7,9,16,18-tetra (4'-isopropylphenyl) benzo [1,2-k: 4,5-k '] difluoranthene 7,9,16,18-tetra (3'-chlorophenyl) benzo [1,2-k: 4,5-k '] difluoranthene 45. 7,9,16,18-tetraethyl-8,17-diphenylbenzo [1,2-k: 4,5-k '] difluoranthene 7,8,9,16,17,18-hexaphenylbenzo [1,2-k: 4,5-k '] difluoranthene

The compound A according to the present invention can be produced according to a method known per se. For example, Chem. Be
r., 126 , 2543 (1993), Tetrahedron, 20 , 1559 (19
64). That is, for example, an acenaphthylene derivative and benzo [1,2-c:
It can be produced by reacting an equivalent of a 4,5-c ′] difuran derivative and then dehydrating the product. Further, cyclopenta [a] acenaphthylene-2-one derivative and 1,1
It can be produced by reacting an equivalent of a 4-benzadiyne derivative [see, for example, Synlett, 75 (199
Refer to the production method described in 4).

The organic electroluminescent device generally has at least one light-emitting layer containing at least one light-emitting component sandwiched between a pair of electrodes. In consideration of the functional levels of hole injection and hole transport, electron injection and electron transport of the compound used in the light-emitting layer, a hole injection transport layer containing a hole injection transport component and / or An electron injection / transport layer containing an injection / transport component can also be provided. For example, when the compound used for the light emitting layer has a good hole injecting function, a hole transporting function or / and an electron injecting function, and an electron transporting function, the light emitting layer is preferably a hole injecting / transporting layer or / and an electron injecting / transporting layer. The element can also be configured to serve as Of course, depending on the case, a structure of a device (single-layer device) without both the hole injection transport layer and the electron injection transport layer may be employed. Further, each of the hole injection transport layer, the electron injection transport layer and the light emitting layer may have a single-layer structure or a multilayer structure,
The hole injecting and transporting layer and the electron injecting and transporting layer can be formed by separately providing a layer having an injection function and a layer having a transport function in each layer.

In the organic electroluminescent device of the present invention, the compound A of the present invention is preferably used for a hole injection / transport component, a light emitting component or an electron injection / transport component, and is preferably used for a hole injection / transport component or a light emitting component. Is more preferable,
It is particularly preferable to use it for a light emitting component. In the organic electroluminescent device of the present invention, the compound A according to the present invention may be used alone or in combination.

The structure of the organic electroluminescent device of the present invention is not particularly limited.
Hole injection / transport layer / emission layer / electron injection / transport layer / cathode device (FIG. 1), (B) anode / hole injection / transport layer / emission layer / cathode device (FIG. 2), (C) anode / emission Layer / electron injection / transport layer / cathode type device (FIG. 3), (D) anode / light emitting layer / cathode type device (FIG. 4) and the like. Further, the device is of a type in which a light emitting layer is sandwiched between electron injection and transport layers (E).
Anode / hole injection / transport layer / electron injection / transport layer / emission layer / electron injection / transport layer / cathode type device (FIG. 5).
The element configuration of the (D) type is, of course, an element of a type in which a light emitting component is sandwiched between a pair of electrodes in a single layer form, and further, for example, (F) a hole injection / transport component, a light emitting component, An element of a type in which an electron injection / transport component is mixed and sandwiched between a pair of electrodes (FIG. 6), and (G) a layer in which a hole injection / transport component and a light emitting component are mixed, between a pair of electrodes. There is an element of a sandwiched type (FIG. 7) or (H) an element of a type sandwiched between a pair of electrodes in a single-layer form in which a light emitting component and an electron injection / transport component are mixed (FIG. 8).

The organic electroluminescent device of the present invention is not limited to these device configurations, and each type of device may be provided with a plurality of hole injection / transport layers, light emitting layers, and electron injection / transport layers. it can. In each type of device, a light emitting component is provided between the hole injecting and transporting layer and the light emitting layer, and / or between the hole injecting and transporting component and the light emitting component. And a mixed layer of an electron injection and transport component. More preferred configurations of the organic electroluminescent device are (A) type device, (B) type device, and (C) type device.
Element, (E) element, (F) element, (G) element or (H) element, more preferably (A) element, (B) element, (C) element , (F) type element or (H) type element.

As the organic electroluminescent device of the present invention, for example, (A) anode / hole injection / transport layer / light emitting layer / electron injection / transport layer / cathode type device shown in FIG. 1 will be described.
In FIG. 1, 1 is a substrate, 2 is an anode, 3 is a hole injection / transport layer, 4 is a light emitting layer, 5 is an electron injection / transport layer, 6 is a cathode,
Reference numeral 7 denotes a power supply.

The organic electroluminescent device of the present invention is preferably supported on a substrate 1. The substrate is not particularly limited, but is preferably transparent or translucent. Examples include transparent plastic sheets (for example, sheets of polyester, polycarbonate, polysulfone, polymethyl methacrylate, polypropylene, polyethylene, etc.), translucent plastic sheets, quartz, transparent ceramics, and composite sheets combining these. . Further, the luminescent color can be controlled by combining, for example, a color filter film, a color conversion film, and a dielectric reflection film on the substrate.

As the anode 2, it is preferable to use a metal, an alloy or an electrically conductive compound having a relatively large work function as an electrode material. As the electrode material used for the anode, for example, gold, platinum, silver, copper, cobalt, nickel,
Palladium, vanadium, tungsten, tin oxide, zinc oxide, ITO (indium tin oxide), polythiophene, polypyrrole, and the like can be given. These electrode substances may be used alone or in combination of two or more. The anode can be formed on the substrate by using such an electrode material by a method such as a vapor deposition method and a sputtering method. Further, the anode may have a single-layer structure or a multilayer structure. The sheet electric resistance of the anode is preferably several hundred Ω / □.
Hereinafter, more preferably, it is set to about 5 to 50 Ω / □. The thickness of the anode depends on the material of the electrode substance to be used, but is generally about 5 to 1000 nm, more preferably,
It is set to about 10 to 500 nm.

The hole injecting and transporting layer 3 is a layer containing a compound having a function of facilitating the injection of holes (holes) from the anode and a function of transporting the injected holes. The hole injecting and transporting layer is formed of the compound A according to the present invention and / or another compound having a hole injecting and transporting function (for example, phthalocyanine derivative, triarylmethane derivative, triarylamine derivative, oxazole derivative, hydrazone derivative, stilbene derivative) , Pyrazoline derivatives, polysilane derivatives, polyphenylenevinylene and its derivatives,
Polythiophene and a derivative thereof, a poly-N-vinylcarbazole derivative, and the like). The compounds having a hole injection / transport function may be used alone or in combination.

Other compounds having a hole injection / transport function used in the present invention include triarylamine derivatives (for example, 4,4′-bis [N-phenyl-N- (4 ″)).
-Methylphenyl) amino] biphenyl, 4,4'-bis [N-phenyl-N- (3 "-methylphenyl) amino] biphenyl, 4,4'-bis [N-phenyl-N-
(3 "-methoxyphenyl) amino] biphenyl, 4,
4'-bis [N-phenyl-N- (1 "-naphthyl) amino] biphenyl, 3,3'-dimethyl-4,4'-bis [N-phenyl-N- (3" -methylphenyl) amino] Biphenyl, 1,1-bis [4 ′-[N, N-di (4 ″ -methylphenyl) amino] phenyl] cyclohexane, 9,10-bis [N- (4′-methylphenyl) -N- (4 "-N-butylphenyl) amino] phenanthrene, 3,8-bis (N, N-diphenylamino) -6-phenylphenanthridine, 4-methyl-
N, N-bis [4 ", 4"'-bis[N',N'-di (4
-Methylphenyl) amino] biphenyl-4-yl] aniline, N, N'-bis [4- (diphenylamino) phenyl] -N, N'-diphenyl-1,3-diaminobenzene, N, N'-bis [4- (diphenylamino) phenyl] -N, N'-diphenyl-1,4-diaminobenzene, 5,5 "-bis [4- (bis [4-methylphenyl] amino) phenyl] -2,2 ' : 5 ', 2 "-terthiophene, 1,3,5-tris (diphenylamino) benzene, 4,4', 4" -tris (N-carbazolyl) triphenylamine, 4,4 ', 4 "-tris [N- (3 "'-methylphenyl) -N-phenylamino] triphenylamine, 1,3,5-tris [N-
(4-diphenylaminophenyl) phenylamino] benzene, etc.), polythiophene and derivatives thereof, and poly-N-vinylcarbazole derivatives are more preferred. When the compound A according to the present invention is used in combination with another compound having a hole injecting and transporting function, the proportion of the compound A according to the present invention in the hole injecting and transporting layer is preferably 0.1 to 40% by weight. Prepare to about.

The light emitting layer 4 has a hole and electron injection function,
This is a layer containing a compound having a transport function thereof and a function of generating excitons by recombination of holes and electrons. The light-emitting layer is a compound A according to the present invention and / or another fluorescent compound having a light-emitting function (eg, an acridone derivative, a quinacridone derivative, a polycyclic aromatic compound [eg,
Rubrene, anthracene, tetracene, pyrene, perylene, chrysene, decacyclene, coronene, tetraphenylcyclopentadiene, pentaphenylcyclopentadiene, 9,10-diphenylanthracene, 9,10-
Bis (phenylethynyl) anthracene, 1,4-bis (9′-ethynylanthracenyl) benzene, 4,4 ′
-Bis (9 "-ethynylanthracenyl) biphenyl], a triarylamine derivative (for example, the compounds described above as compounds having a hole injecting and transporting function), and an organometallic complex [for example, tris (8- Quinolinolate) aluminum, bis (10-benzo [h]
Quinolinolate) beryllium, zinc salt of 2- (2'-hydroxyphenyl) benzoxazole, 2- (2'-
4-hydroxyphenyl) benzothiazole zinc salt, 4-
Zinc salts of hydroxyacridine], stilbene derivatives [eg, 1,1,4,4-tetraphenyl-1,3-
Butadiene, 4,4'-bis (2,2-diphenylvinyl) biphenyl], coumarin derivative [for example, coumarin 1, coumarin 6, coumarin 7, coumarin 30, coumarin 106, coumarin 138, coumarin 151, coumarin 1
52, coumarin 153, coumarin 307, coumarin 31
1. Coumarin 314, Coumarin 334, Coumarin 33
8, coumarin 343, coumarin 500], pyran derivatives [eg, DCM1, DCM2], oxazone derivatives [eg, Nile Red], benzothiazole derivatives,
Benzoxazole derivatives, benzimidazole derivatives, pyrazine derivatives, cinnamate derivatives, poly-
N-vinyl carbazole and its derivatives, polythiophene and its derivatives, polyphenylene and its derivatives, polyfluorene and its derivatives, polyphenylene vinylene and its derivatives, polybiphenylene vinylene and its derivatives, polyterphenylene vinylene and its derivatives, polynaphthylene vinylene and And at least one of its derivatives, polythienylenevinylene and derivatives thereof).

In the organic electroluminescent device of the present invention, the light-emitting layer preferably contains the compound A of the present invention. When the compound A according to the present invention and a compound having another light-emitting function are used in combination, the ratio of the compound A according to the present invention in the light-emitting layer is preferably 0.001 to 99.99.
About 9% by weight, more preferably 0.01 to 99.99
% By weight, more preferably about 0.1 to 99.9% by weight.

As the other compound having a light emitting function used in the present invention, a light emitting organic metal complex is more preferable. For example, as described in J. Appl. Phys., 65 , 3610 (1989) and JP-A-5-214332, the light-emitting layer can be composed of a host compound and a guest compound (dopant). The compound A according to the present invention can be used as a host compound to form a light-emitting layer, and further can be used as a guest compound to form a light-emitting layer. When the light emitting layer is formed using the compound A according to the present invention as a guest compound, the host compound includes
Luminescent organometallic complexes are preferred. In this case, the compound A according to the present invention is preferably used in an amount of about 0.001 to 40% by weight based on the luminescent organometallic complex, and more preferably,
About 0.01 to 30% by weight, particularly preferably 0.1 to
Use about 10% by weight.

The luminescent organometallic complex used in combination with the compound A according to the present invention is not particularly limited.
A luminescent organic aluminum complex is preferable, and a luminescent organic aluminum complex having a substituted or unsubstituted 8-quinolinolate ligand is more preferable. Preferred luminescent organometallic complexes include, for example, general formulas (a) to (c)
And a luminescent organic aluminum complex represented by (Q) _3- Al (a) (wherein Q represents a substituted or unsubstituted 8-quinolinolate ligand) (Q) _2- Al-OL (b) (wherein Q represents substituted 8 -Represents a quinolinolate ligand, O
-L is a phenolate ligand, and L represents a hydrocarbon group having 6 to 24 carbon atoms including a phenyl moiety.) (Q) _2- Al-O-Al- (Q) ₂ (c) Q represents a substituted 8-quinolinolate ligand)

Specific examples of the luminescent organometallic complex include, for example, tris (8-quinolinolate) aluminum, tris (4-methyl-8-quinolinolate) aluminum, tris (5-methyl-8-quinolinolate) aluminum, tris ( 3,4-dimethyl-8-quinolinolate) aluminum, tris (4,5-dimethyl-8-quinolinolate) aluminum, tris (4,6-dimethyl-8-quinolinolate) aluminum, bis (2-methyl-8-quinolinolate) (Phenolate) aluminum, bis (2-methyl-8-quinolinolate) (2-
Methylphenolate) aluminum, bis (2-methyl-8-quinolinolate) (3-methylphenolate) aluminum, bis (2-methyl-8-quinolinolate)
(4-methylphenolate) aluminum, bis (2-
Methyl-8-quinolinolate) (2-phenylphenolate) aluminum, bis (2-methyl-8-quinolinolate) (3-phenylphenolate) aluminum,

Bis (2-methyl-8-quinolinolate)
(4-phenylphenolate) aluminum, bis (2
-Methyl-8-quinolinolate) (2,3-dimethylphenolate) aluminum, bis (2-methyl-8-quinolinolate) (2,6-dimethylphenolate) aluminum, bis (2-methyl-8-quinolinolate)
(3,4-dimethylphenolato) aluminum, bis (2-methyl-8-quinolinolate) (3,5-dimethylphenolate) aluminum, bis (2-methyl-8
-Quinolinolate) (3,5-di-tert-butylphenolate) aluminum, bis (2-methyl-8-quinolinolate) (2,6-diphenylphenolate) aluminum, bis (2-methyl-8-quinolinolate)
(2,4,6-triphenylphenolate) aluminum, bis (2-methyl-8-quinolinolate) (2
4,6-trimethylphenolato) aluminum, bis (2-methyl-8-quinolinolate) (2,4,5,6
-Tetramethylphenolate) aluminum, bis (2
-Methyl-8-quinolinolate) (1-naphtholate)
Aluminum, bis (2-methyl-8-quinolinolate) (2-naphtholate) aluminum, bis (2,4
-Dimethyl-8-quinolinolate) (2-phenylphenolato) aluminum, bis (2,4-dimethyl-8)
-Quinolinolate) (3-phenylphenolate) aluminum, bis (2,4-dimethyl-8-quinolinolate) (4-phenylphenolate) aluminum, bis (2,4-dimethyl-8-quinolinolate) (3,5-
Dimethylphenolate) aluminum, bis (2,4-
Dimethyl-8-quinolinolate) (3,5-di-tert-
Butyl phenolate) aluminum,

Bis (2-methyl-8-quinolinolate)
Aluminum-μ-oxo-bis (2-methyl-8-quinolinolato) aluminum, bis (2,4-dimethyl-8-quinolinolato) aluminum-μ-oxo-bis (2,4-dimethyl-8-quinolinolato) aluminum, Bis (2-methyl-4-ethyl-8-quinolinolato) aluminum-μ-oxo-bis (2-methyl-
4-ethyl-8-quinolinolate) aluminum, bis (2-methyl-4-methoxy-8-quinolinolate) aluminum-μ-oxo-bis (2-methyl-4-methoxy-8-quinolinolate) aluminum, bis (2-
Methyl-5-cyano-8-quinolinolato) aluminum-μ-oxo-bis (2-methyl-5-cyano-8-
Quinolinolate) aluminum, bis (2-methyl-5)
-Trifluoromethyl-8-quinolinolato) aluminum- [mu] -oxo-bis (2-methyl-5-trifluoromethyl-8-quinolinolato) aluminum. Of course, the luminescent organometallic complex may be used alone or in combination.

The electron injection / transport layer 5 is a layer containing a compound having a function of facilitating the injection of electrons from the cathode and a function of transporting the injected electrons. The electron injecting and transporting layer is formed of the compound A according to the present invention and / or another compound having an electron injecting and transporting function (eg, an organometallic complex [eg, tris (8-quinolinolate) aluminum, bis (10-benzo [h] quinolinolate) )beryllium〕,
An oxadiazole derivative, a triazole derivative, a triazine derivative, a perylene derivative, a quinoline derivative, a quinoxaline derivative, a diphenylquinone derivative, a nitro-substituted fluorenone derivative, a thiopyrandioxide derivative, or the like can be formed. When the compound A according to the present invention is used in combination with another compound having an electron injecting and transporting function, the ratio of the compound A according to the present invention in the electron injecting and transporting layer is preferably about 0.1 to 40% by weight. Prepare. In the present invention, the compound A according to the present invention and an organometallic complex [for example, the general formulas (a) to
The compound represented by the general formula (c)] is preferably used in combination to form an electron injection / transport layer.

As the cathode 6, it is preferable to use a metal, an alloy or an electrically conductive compound having a relatively small work function as an electrode material. Examples of the electrode material used for the cathode include lithium, lithium-indium alloy, sodium, sodium-potassium alloy, calcium, magnesium, magnesium-silver alloy, magnesium-indium alloy, indium, ruthenium, titanium,
Manganese, yttrium, aluminum, an aluminum-lithium alloy, an aluminum-calcium alloy, an aluminum-magnesium alloy, a graphite thin film and the like can be given. These electrode substances may be used alone or in combination of two or more.

The cathode can be formed on the electron injecting and transporting layer by using these electrode materials by, for example, a vapor deposition method, a sputtering method, an ionization vapor deposition method, an ion plating method, a cluster ion beam method, or the like. . Further, the cathode may have a single-layer structure or a multilayer structure. The sheet electric resistance of the cathode is several hundred Ω.
/ □ or less is preferable. The thickness of the cathode depends on the material of the electrode substance to be used, but generally ranges from 5 to 1000.
nm, more preferably about 10-500 nm. In order to efficiently extract the light emitted from the organic electroluminescent device, at least one electrode of the anode or the cathode is
It is preferably transparent or translucent, and in general, it is more preferable to set the material and thickness of the anode so that the transmittance of emitted light is 70% or more.

Further, in the organic electroluminescent device of the present invention, at least one layer may contain a singlet oxygen quencher. The singlet oxygen quencher is not particularly limited and includes, for example, rubrene,
Nickel complexes, diphenylisobenzofuran and the like can be mentioned, and rubrene is particularly preferred. The layer containing the singlet oxygen quencher is not particularly limited, but is preferably a light emitting layer or a hole injection transport layer, and more preferably a hole injection transport layer.
When a singlet oxygen quencher is contained in the hole injecting and transporting layer, for example, the singlet oxygen quencher may be uniformly contained in the hole injecting and transporting layer, and a layer adjacent to the hole injecting and transporting layer (for example, a light emitting layer, (An electron injection / transport layer having a light emitting function). The content of the singlet oxygen quencher is from 0.01 to 50% by weight, preferably from 0.0 to 50% by weight of the total amount constituting the contained layer (for example, the hole injection / transport layer).
5 to 30% by weight, more preferably 0.1 to 20% by weight
It is.

The method of forming the hole injecting and transporting layer, the light emitting layer, and the electron injecting and transporting layer is not particularly limited. For example, a vacuum evaporation method, an ionization evaporation method, a solution coating method (for example, a spin coating method, a casting method, Method, dip coating method,
It can be manufactured by forming a thin film by a bar coating method, a roll coating method, a Langmuir-Brosette method, or the like. When forming each layer by a vacuum deposition method, the conditions of the vacuum deposition are not particularly limited,
It is carried out under a vacuum of about 10 ^-5 Torr or less, a boat temperature (deposition source temperature) of about 50 to 400 ° C., a substrate temperature of about −50 to 300 ° C., and a deposition rate of about 0.005 to 50 nm / sec. Is preferred. In this case, by forming the layers such as the hole injecting and transporting layer, the light emitting layer, and the electron injecting and transporting layer continuously under vacuum, an organic electroluminescent device having more excellent various characteristics can be manufactured. When each layer such as a hole injection transport layer, a light emitting layer, and an electron injection transport layer is formed using a plurality of compounds by a vacuum deposition method, each boat containing the compounds is individually temperature-controlled and co-deposited. Is preferred.

When each layer is formed by a solution coating method,
The components forming each layer or the components and a binder resin or the like are dissolved or dispersed in a solvent to form a coating liquid. Examples of the binder resin that can be used for each of the hole injection transport layer, the light emitting layer, and the electron injection transport layer include poly-N-vinylcarbazole, polyarylate, polystyrene, polyester, polysiloxane, polymethyl acrylate, and the like.
Polymethyl methacrylate, polyether, polycarbonate, polyamide, polyimide, polyamideimide, polyparaxylene, polyethylene, polyphenylene oxide, polyethersulfone, polyaniline and its derivatives, polythiophene and its derivatives, polyphenylenevinylene and its derivatives, polyfluorene and its Derivatives, high molecular compounds such as polythienylenevinylene and derivatives thereof are exemplified. The binder resin may be used alone or in combination.

When each layer is formed by a solution coating method,
The components forming each layer or the components and a binder resin are combined with a suitable organic solvent (for example, hexane, octane,
Decane, toluene, xylene, ethylbenzene, hydrocarbon solvents such as 1-methylnaphthalene, for example, acetone, methyl ethyl ketone, methyl isobutyl ketone, ketone solvents such as cyclohexanone, for example, dichloromethane, chloroform, tetrachloromethane, dichloroethane, trichloroethane, Halogenated hydrocarbon solvents such as tetrachloroethane, chlorobenzene, dichlorobenzene, and chlorotoluene, for example, ester solvents such as ethyl acetate, butyl acetate, and amyl acetate, for example, methanol, propanol, butanol, pentanol, hexanol, and cyclohexanol , Methyl cellosolve, ethyl cellosolve, alcohol solvents such as ethylene glycol, for example, dibutyl ether, tetrahydrofuran,
Dioxane, ether solvents such as anisole, for example,
Polar solvents such as N, N-dimethylformamide, N, N-dimethylacetamide, 1-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, dimethyl sulfoxide) and / or dissolved in water Alternatively, a thin film can be formed by various coating methods by dispersing the mixture into a coating liquid.

The method of dispersion is not particularly limited. For example, the particles can be dispersed into fine particles using a ball mill, a sand mill, a paint shaker, an attritor, a homogenizer or the like. The concentration of the coating solution is not particularly limited, and can be set to a concentration range suitable for producing a desired thickness depending on a coating method to be performed, and is generally about 0.1 to 50% by weight. Preferably, the solution concentration is about 1 to 30% by weight. When a binder resin is used, the amount of the binder resin is not particularly limited. However, in general, the amount of the binder resin is limited to the components forming each layer (when forming a single-layer element, the total 5) to 99.9% by weight
Level, preferably about 10 to 99% by weight, more preferably about 15 to 90% by weight.

The thicknesses of the hole injecting and transporting layer, the light emitting layer and the electron injecting and transporting layer are not particularly limited, but are generally preferably set to about 5 nm to 5 μm.
A protective layer (sealing layer) may be provided on the fabricated device for the purpose of preventing contact with oxygen, moisture, or the like, or the device may be formed of, for example, paraffin, liquid paraffin, silicon oil, fluorocarbon oil, zeolite, or the like. It can be protected by being enclosed in an inert substance such as a contained fluorocarbon oil. Examples of the material used for the protective layer include organic polymer materials (for example, fluorinated resin, epoxy resin, silicone resin, epoxy silicone resin, polystyrene, polyester, polycarbonate, polyamide, polyimide, polyamideimide, polyparaxylene, polyethylene) , Polyphenylene oxide), inorganic materials (for example, diamond thin film, amorphous silica, electrically insulating glass, metal oxide, metal nitride, metal carbide,
Metal sulfide), and a photocurable resin. The material used for the protective layer may be used alone or in combination of two or more. The protective layer may have a single-layer structure or a multilayer structure.

Further, for example, a metal oxide film (for example, an aluminum oxide film) or a metal fluoride film may be provided as a protective film on the electrode. Also, for example, on the surface of the anode,
For example, an interface layer (intermediate layer) composed of an organic phosphorus compound, polysilane, an aromatic amine derivative, and a phthalocyanine derivative
Can also be provided. Further, electrodes, eg, anodes, can be used by treating the surface with, eg, acid, ammonia / hydrogen peroxide, or plasma.

The organic electroluminescent device of the present invention is generally used as a DC-driven device, but can also be used as a pulse-driven or AC-driven device.
Incidentally, the applied voltage is generally about 2 to 30 V. The organic electroluminescent device of the present invention can be used for, for example, a panel light source, various light emitting devices, various display devices, various labels, various sensors, and the like.

[0043]

The present invention will be described in more detail with reference to the following examples, which, of course, are not intended to limit the scope of the present invention. Example 1 A glass substrate having a 200-nm-thick ITO transparent electrode (anode) was subjected to ultrasonic cleaning using a neutral detergent, acetone, and ethanol. The substrate was dried using nitrogen gas, further washed with UV / ozone, fixed to a substrate holder of a vapor deposition device, and then the pressure in the vapor deposition tank was reduced to 3 × 10 ⁻⁶ Torr.
First, 4,4′-bis [N-phenyl-N- (3 ″ -methylphenyl) amino] biphenyl was vapor-deposited on the ITO transparent electrode to a thickness of 75 nm at a vapor deposition rate of 0.2 nm / sec. A hole injecting and transporting layer was formed thereon, and then bis (2-methyl-8-quinolinolate) (4-phenylphenolate) aluminum and benzo [1,2-k: 4,5-k '] difluoranthene were formed thereon. (Compound of Exemplified Compound No. 1) was co-evaporated (weight ratio 100: 0.5) from different evaporation sources to a thickness of 50 nm at an evaporation rate of 0.2 nm / sec to obtain a light emitting layer. (8-quinolinolate) aluminum was deposited at a deposition rate of 0.2 nm / sec to a thickness of 50 nm to form an electron injecting and transporting layer, and magnesium and silver were further deposited thereon at a deposition rate of 0.2 nm / sec at a thickness of 200 nm. Co-deposition to a thickness of (weight ratio 10: 1) An organic electroluminescent device was produced by using the cathode as a cathode, and the vapor deposition was performed while maintaining the reduced pressure of the vapor deposition tank.
When a DC voltage of 12 V was applied in a dry atmosphere,
A current of 5 mA / cm ² flowed. Brightness 2350 cd / m
Green light emission of ² was confirmed.

Examples 2 to 6 In Example 1, instead of using the compound of Exemplified Compound No. 1 in forming the light emitting layer, Exemplified Compound No. 9 was used.
(Example 2), compound of Exemplified Compound No. 14 (Example 3), compound of Exemplified Compound No. 17 (Example 4), compound of Exemplified Compound No. 28 (Example 5), compound of Exemplified Compound No. 42 An organic electroluminescent device was manufactured by the method described in Example 1 except that (Example 6) was used. When a DC voltage of 12 V was applied to each element under a dry atmosphere, green light emission was confirmed. The characteristics were further examined, and the results are shown in Table 1 (Table 1).

Comparative Example 1 In Example 1, when forming the light emitting layer, the compound of Exemplified Compound No. 1 was not used, and bis (2-methyl-8-
An organic electroluminescent device was prepared by the method described in Example 1, except that quinolinolate) (4-phenylphenolate) aluminum alone was used to form a light emitting layer by vapor deposition to a thickness of 50 nm. This device was exposed to a 12 V
As a result, blue light emission was confirmed. The characteristics were further examined, and the results are shown in Table 1.

Comparative Example 2 In Example 1, when forming the light emitting layer, instead of using the compound of Exemplified Compound No. 1, N-methyl-2-
An organic electroluminescent device was manufactured by the method described in Example 1 except that methoxyacridone was used. When a DC voltage of 12 V was applied to this device under a dry atmosphere, blue light emission was confirmed. Further investigate its properties,
The results are shown in Table 1.

[0047]

[Table 1]

Example 7 A glass substrate having a 200 nm-thick ITO transparent electrode (anode) was subjected to ultrasonic cleaning using a neutral detergent, acetone and ethanol. The substrate was dried using nitrogen gas, further washed with UV / ozone, fixed to a substrate holder of a vapor deposition device, and then the pressure in the vapor deposition tank was reduced to 3 × 10 ⁻⁶ Torr.
First, 4,4′-bis [N-phenyl-N- (3 ″ -methylphenyl) amino] biphenyl was vapor-deposited on the ITO transparent electrode to a thickness of 75 nm at a vapor deposition rate of 0.2 nm / sec. Next, bis (2-methyl-8-quinolinolate) (2-phenylphenolate) aluminum and the compound of Exemplified Compound No. 7 were further deposited thereon from a different evaporation source at a deposition rate of 0.2 nm. 5 / sec
It was co-evaporated to a thickness of 0 nm (weight ratio: 100: 1.0) to form a light emitting layer. Next, tris (8-quinolinolato) aluminum was deposited at a deposition rate of 0.2 nm / sec to a thickness of 50 nm to form an electron injection transport layer. Further on that,
Magnesium and silver are deposited at a deposition rate of 0.2 nm / sec.
A cathode was formed by co-evaporation (weight ratio: 10: 1) to a thickness of 0 nm to produce an organic electroluminescent device. In addition, vapor deposition was performed while maintaining the reduced pressure state of the vapor deposition tank. When a DC voltage of 12 V was applied to the manufactured organic electroluminescent device in a dry atmosphere, a current of 58 mA / cm ² flowed. Brightness 237
Green light emission of 0 cd / m ² was confirmed.

Example 8 A glass substrate having a 200 nm-thick ITO transparent electrode (anode) was subjected to ultrasonic cleaning using a neutral detergent, acetone and ethanol. The substrate was dried using nitrogen gas, further washed with UV / ozone, fixed to a substrate holder of a vapor deposition device, and then the pressure in the vapor deposition tank was reduced to 3 × 10 ⁻⁶ Torr.
First, 4,4′-bis [N-phenyl-N- (3 ″ -methylphenyl) amino] biphenyl was vapor-deposited on the ITO transparent electrode to a thickness of 75 nm at a vapor deposition rate of 0.2 nm / sec. Then, bis (2-methyl-8-quinolinolate) aluminum-μ was formed thereon.
-Oxo-bis (2-methyl-8-quinolinolato) aluminum and the compound of Exemplified Compound No. 36 were co-deposited from different deposition sources at a deposition rate of 0.2 nm / sec to a thickness of 50 nm (weight ratio 100: 2. 0) to form a light emitting layer.
Next, tris (8-quinolinolate) aluminum is
Deposit to a thickness of 50 nm at a deposition rate of 0.2 nm / sec.
An electron injection transport layer was used. Further, magnesium and silver were co-deposited thereon at a deposition rate of 0.2 nm / sec to a thickness of 200 nm (weight ratio: 10: 1) to form a cathode, thereby producing an organic electroluminescent device. In addition, vapor deposition was performed while maintaining the reduced pressure state of the vapor deposition tank. When a DC voltage of 12 V was applied to the produced organic electroluminescent device under a dry atmosphere, the voltage was 57 m.
A / cm ² current flowed. Green light emission with a luminance of 2320 cd / m ² was confirmed.

Example 9 A glass substrate having a 200 nm-thick ITO transparent electrode (anode) was subjected to ultrasonic cleaning using a neutral detergent, acetone and ethanol. The substrate was dried using nitrogen gas, further washed with UV / ozone, fixed to a substrate holder of a vapor deposition device, and then the pressure in the vapor deposition tank was reduced to 3 × 10 ⁻⁶ Torr.
First, 4,4′-bis [N-phenyl-N- (3 ″ -methylphenyl) amino] biphenyl was vapor-deposited on the ITO transparent electrode to a thickness of 75 nm at a vapor deposition rate of 0.2 nm / sec. Then, bis (2,4-dimethyl-8-quinolinolato) aluminum-μ-oxo-bis (2,4-dimethyl-8-quinolinolato) aluminum and a compound of Exemplified Compound No. 11 were formed thereon. Compounds were collected from different sources at a deposition rate of 0.2 nm / sec.
It was co-evaporated to a thickness of 0 nm (weight ratio: 100: 4.0) to form a light emitting layer. Next, tris (8-quinolinolato) aluminum was deposited at a deposition rate of 0.2 nm / sec to a thickness of 50 nm to form an electron injection transport layer. Further on that,
Magnesium and silver are deposited at a deposition rate of 0.2 nm / sec.
A cathode was formed by co-evaporation (weight ratio: 10: 1) to a thickness of 0 nm to produce an organic electroluminescent device. In addition, vapor deposition was performed while maintaining the reduced pressure state of the vapor deposition tank. When a DC voltage of 12 V was applied to the manufactured organic electroluminescent device in a dry atmosphere, a current of 60 mA / cm ² flowed. Brightness 213
Green light emission of 0 cd / m ² was confirmed.

Example 10 A glass substrate having a 200-nm-thick ITO transparent electrode (anode) was subjected to ultrasonic cleaning using a neutral detergent, acetone, and ethanol. The substrate was dried using nitrogen gas, further washed with UV / ozone, fixed to a substrate holder of a vapor deposition device, and then the pressure in the vapor deposition tank was reduced to 3 × 10 ⁻⁶ Torr.
First, 4,4′-bis [N-phenyl-N- (3 ″ -methylphenyl) amino] biphenyl was vapor-deposited on the ITO transparent electrode to a thickness of 75 nm at a vapor deposition rate of 0.2 nm / sec. Next, tris (8-quinolinolato) aluminum and the compound of Exemplified Compound No. 32 were deposited thereon from different evaporation sources at a deposition rate of 0.2.
Co-deposition to a thickness of 50 nm at nm / sec (weight ratio 100:
1.0) to form a light-emitting layer also serving as an electron injection / transport layer. Further, magnesium and silver were further deposited thereon at a deposition rate of 0.2 n.
Co-deposition at 200 m / sec to a thickness of 200 nm (weight ratio 10:
1) The resultant was used as a cathode to produce an organic electroluminescent device. still,
The vapor deposition was performed while maintaining the reduced pressure state of the vapor deposition tank. When a DC voltage of 12 V was applied to the manufactured organic electroluminescent device in a dry atmosphere, a current of 58 mA / cm ² flowed. Green light emission with a luminance of 1970 cd / m ² was confirmed.

Example 11 A glass substrate having a 200-nm-thick ITO transparent electrode (anode) was subjected to ultrasonic cleaning using a neutral detergent, acetone, and ethanol. The substrate was dried using nitrogen gas, further washed with UV / ozone, fixed to a substrate holder of a vapor deposition device, and then the pressure in the vapor deposition tank was reduced to 3 × 10 ⁻⁶ Torr.
First, 4,4′-bis [N-phenyl-N- (3 ″ -methylphenyl) amino] biphenyl was vapor-deposited on the ITO transparent electrode to a thickness of 75 nm at a vapor deposition rate of 0.2 nm / sec. Next, a compound of Exemplified Compound No. 1 was deposited thereon to a thickness of 50 nm at a deposition rate of 0.2 nm / sec to form a light emitting layer. 3-bis [5 '-(p-tert-butylphenyl) -1,3,4-oxadiazol-2'-yl] benzene is deposited at a deposition rate of 0.2 nm / sec to a thickness of 50 nm, An electron injecting and transporting layer was further formed thereon, and magnesium and silver were further deposited thereon at a deposition rate of 0.2 nm / sec.
Co-deposit (weight ratio 10: 1) to a thickness of nm to form a cathode,
An organic electroluminescent device was manufactured. In addition, vapor deposition was performed while maintaining the reduced pressure state of the vapor deposition tank. When a DC voltage of 14 V was applied to the produced organic electroluminescent device in a dry atmosphere, a current of 48 mA / cm ² flowed. Brightness 1840c
Green light emission of d / m ² was confirmed.

Example 12 A glass substrate having a 200 nm-thick ITO transparent electrode (anode) was subjected to ultrasonic cleaning using a neutral detergent, acetone and ethanol. The substrate was dried using nitrogen gas, further washed with UV / ozone, fixed to a substrate holder of a vapor deposition device, and then the pressure in the vapor deposition tank was reduced to 3 × 10 ⁻⁶ Torr.
First, the compound of Exemplified Compound No. 27 was deposited on the ITO transparent electrode to a thickness of 55 nm at a deposition rate of 0.2 nm / sec to form a light emitting layer. Then, on top of that, 1,3-bis [5 ′-(p-tert-butylphenyl) -1,3,4-
[Oxadiazol-2'-yl] benzene was deposited at a deposition rate of 0.2 nm / sec to a thickness of 75 nm to form an electron injecting and transporting layer. On top of that, magnesium and silver,
A co-deposition (weight ratio: 10: 1) was performed at a deposition rate of 0.2 nm / sec to a thickness of 200 nm to form a cathode, thereby producing an organic electroluminescent device. In addition, vapor deposition was performed while maintaining the reduced pressure state of the vapor deposition tank. When a DC voltage of 15 V was applied to the manufactured organic electroluminescent device under a dry atmosphere, the voltage was 68 mA / c.
m ² of current flowed. Green light emission with a luminance of 1250 cd / m ² was confirmed.

Example 13 A glass substrate having a 200-nm-thick ITO transparent electrode (anode) was subjected to ultrasonic cleaning using a neutral detergent, acetone, and ethanol. The substrate was dried using nitrogen gas and further washed with UV / ozone. Next, on the ITO transparent electrode, poly-N-vinylcarbazole (weight average molecular weight 1
50,000), 1,1,4,4-tetraphenyl-1,
3-butadiene (a blue light-emitting component), a compound of Exemplified Compound 19, and DCM1 ["4- (dicyanomethylene)
-2-methyl-6- (4'-dimethylaminostyryl)
-4H-pyran "(orange light-emitting component)], and a light-emitting layer of 400 nm was formed by dip coating using a 3% by weight dichloroethane solution containing 100: 5: 3: 2 by weight. Next, after fixing the glass substrate having the light emitting layer to the substrate holder of the vapor deposition apparatus, the pressure in the vapor deposition tank was reduced to 3 × 10 ⁻⁶ Torr. -Tert-butylphenyl) -4-phenyl-5- (4 "-biphenyl)-
1,2,4-triazole is deposited at a deposition rate of 0.2 nm / se.
After vapor deposition to a thickness of 20 nm by c, tris (8-quinolinolate) aluminum was further vapor-deposited thereon to a thickness of 30 nm at a vapor deposition rate of 0.2 nm / sec to form an electron injection transport layer. Further, magnesium and silver were co-deposited thereon at a deposition rate of 0.2 nm / sec to a thickness of 200 nm (weight ratio: 10: 1) to form a cathode, thereby producing an organic electroluminescent device. In addition, vapor deposition was performed while maintaining the reduced pressure state of the vapor deposition tank. When a DC voltage of 12 V was applied to the produced organic electroluminescent device under a dry atmosphere, the voltage was 74 mA / c.
m ² of current flowed. White light emission with a luminance of 1120 cd / m ² was confirmed.

Example 14 A glass substrate having a 200 nm-thick ITO transparent electrode (anode) was subjected to ultrasonic cleaning using a neutral detergent, acetone and ethanol. The substrate was dried using nitrogen gas and further washed with UV / ozone. Next, on the ITO transparent electrode, poly-N-vinylcarbazole (weight average molecular weight 1
50000), 1,3-bis [5 '-(p-tert-butylphenyl) -1,3,4-oxadiazole-2'-
Yl] benzene and the compound of Exemplified Compound No. 13
A 300 nm light emitting layer was formed by dip coating using a 3% by weight dichloroethane solution containing each in a weight ratio of 100: 30: 3. Next, after fixing the glass substrate having the light emitting layer to the substrate holder of the vapor deposition apparatus, the pressure in the vapor deposition tank was reduced to 3 × 10 ⁻⁶ Torr. Further, on the light emitting layer, magnesium and silver were deposited at a deposition rate of 0.1.
Co-deposition to a thickness of 200 nm at 2 nm / sec (weight ratio 1
0: 1) to form a cathode to produce an organic electroluminescent device.
When a DC voltage of 15 V was applied to the manufactured organic electroluminescent device in a dry atmosphere, a current of 76 mA / cm ² flowed. Green light emission with a luminance of 1420 cd / m ² was confirmed.

Comparative Example 3 The procedure of Example 14 was repeated except that 1,1,4,4-tetraphenyl-1,3-butadiene was used instead of the compound of Exemplified Compound No. 13 in forming the light-emitting layer. An organic electroluminescent device was produced by the method described in Example 14. When a DC voltage of 15 V was applied to the produced organic electric field device under a dry atmosphere, a current of 86 mA / cm ² flowed. Blue light emission with a luminance of 680 cd / m ² was confirmed.

Example 15 A glass substrate having a 200 nm-thick ITO transparent electrode (anode) was subjected to ultrasonic cleaning using a neutral detergent, acetone and ethanol. The substrate was dried using nitrogen gas and further washed with UV / ozone. Next, on the ITO transparent electrode, polycarbonate (weight average molecular weight: 50,000),
4,4'-bis [N-phenyl-N- (3 "-methylphenyl) amino] biphenyl, bis (2-methyl-8-
Quinolinolate) aluminum-μ-oxo-bis (2
-Methyl-8-quinolinolate) aluminum and the compound of Exemplified Compound No. 30 were each added at a weight ratio of 100:
Using a 3% by weight dichloroethane solution containing 40: 60: 1 in a ratio of 300 nm by dip coating.
Was formed. Next, after fixing the glass substrate having the light emitting layer to the substrate holder of the vapor deposition apparatus, the pressure in the vapor deposition tank was reduced to 3 × 10 ⁻⁶ Torr. Further, on the light emitting layer, magnesium and silver were co-deposited (weight ratio: 10: 1) to a thickness of 200 nm at a deposition rate of 0.2 nm / sec to form an organic electroluminescent device. When a DC voltage of 15 V was applied to the manufactured organic electroluminescent device in a dry atmosphere, a current of 66 mA / cm ² flowed. Brightness 75
Green light emission of 0 cd / m ² was confirmed.

[0058]

According to the present invention, it has become possible to provide an organic electroluminescent device having excellent light emission luminance.

[Brief description of the drawings]

FIG. 1 is a schematic structural view of an example (A) of an organic electroluminescent element.

FIG. 2 is a schematic structural diagram of an example (B) of an organic electroluminescent element.

FIG. 3 is a schematic structural view of an example (C) of an organic electroluminescent element.

FIG. 4 is a schematic structural diagram of an example (D) of an organic electroluminescent element.

FIG. 5 is a schematic structural diagram of an example (E) of an organic electroluminescent element.

FIG. 6 is a schematic structural diagram of an example (F) of an organic electroluminescent element.

FIG. 7 is a schematic structural diagram of an example (G) of an organic electroluminescent element.

FIG. 8 is a schematic structural view of an example (H) of an organic electroluminescent element.

[Explanation of symbols]

 1: substrate 2: anode 3: hole injection / transport layer 3a: hole injection / transport component 4: light-emitting layer 4a: light-emitting component 5: electron injection / transport layer 5 ″: electron injection / transport layer 5a: electron injection / transport component 6: cathode 7: Power supply

Claims (6)

[Claims] 1. A benzo [1,2-k: 4,5-between a pair of electrodes.
k '] An organic electroluminescent device comprising at least one layer containing at least one difluoranthene derivative. 2. The organic electroluminescent device according to claim 1, wherein the layer containing the benzo [1,2-k: 4,5-k ′] difluoranthene derivative is a light emitting layer. 3. The layer containing a benzo [1,2-k: 4,5-k ′] difluoranthene derivative further contains a luminescent organometallic complex. 3. The organic electroluminescent device according to 2. 4. The organic electroluminescent device according to claim 1, further comprising a hole injection / transport layer between the pair of electrodes. 5. The organic electroluminescent device according to claim 1, further comprising an electron injection / transport layer between the pair of electrodes. 6. The method according to claim 1, wherein the benzo [1,2-k: 4,5-k ′] difluoranthene derivative is a compound represented by the general formula (1). The organic electroluminescent device according to claim 1. Embedded image (Wherein, X _{1 to} X ₁₈ are a hydrogen atom, a halogen atom, a straight chain,
Represents a branched or cyclic alkyl group, a straight-chain, branched or cyclic alkoxy group, or a substituted or unsubstituted aryl group)