JPH09165573A - Luminescent material for organic electroluminescent element and organic electroluminescent element using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a luminescent material for organic electroluminescent element capable of emitting a high-intensity light in high efficiency and hardly deteriorating luminescence to afford a highly reliable luminescent material for organic electroluminesent element and an electroluminescent element using the same. SOLUTION: This luminescent material for organic electroluminescent element is expressed by the formula. An organic elctrouminescent element having a luminescent layer containing this material expressed by the formula as its luminescent layer in an electroluminescent element obtained by forming a luminescent layer or a thin layer of an organic compound containing a luminescent later between a pair of electrodes.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a light emitting material for an organic electroluminescence (EL) element used for a flat light source or a display and a high brightness light emitting element.

[0002]

2. Description of the Related Art An EL device using an organic substance is expected to be used as an inexpensive, large-area, full-color display device of a solid light emitting type, and many developments have been made. Generally EL
Is composed of a light-emitting layer and a pair of opposed electrodes sandwiching the layer. In light emission, when an electric field is applied between both electrodes, electrons are injected from the cathode side and holes are injected from the anode side. Further, the electrons are recombined with holes in the light emitting layer, and energy is emitted as light when the energy level returns from the conduction band to the valence band.

[0003] Conventional organic EL devices have a higher driving voltage and lower luminous brightness and luminous efficiency than inorganic EL devices.
In addition, the characteristic deterioration was remarkable, and it had not been put to practical use.
2. Description of the Related Art In recent years, an organic EL in which a thin film containing an organic compound having high fluorescence quantum efficiency that emits light at a low voltage of 10 V or less is laminated.
Devices have been reported and are of interest (see Applied Physics Letters, vol. 51, p. 913, 1987). This method uses a metal chelate complex for a light emitting layer and an amine compound for a hole injection layer to obtain high-luminance green light emission. The luminance is several hundred cd at a DC voltage of 6 to 7 V.
/ M ² , and a maximum luminous efficiency of 1.5 lm / W, which is close to the practical range.

[0004] However, organic EL devices up to now have improved luminous intensity due to the improved structure, but do not yet have sufficient luminous brightness. In addition, there is a major problem that the stability upon repeated use is poor. This is because, for example, a metal chelate complex such as tris (8-hydroxyquinolinato) aluminum complex (Alq3) is
It was chemically unstable at the time of electroluminescence, had poor adhesion to the cathode, and was greatly deteriorated by light emission for a short time. For the above reasons, in order to develop an organic EL element having a large emission brightness and excellent stability in repeated use, it is desired to develop a durable light emitting material having an excellent light emitting ability. There is.

[0005]

SUMMARY OF THE INVENTION An object of the present invention is to provide an organic EL device having a high emission luminance and excellent stability when used repeatedly. As a result of intensive studies by the present inventors, an organic EL device using a light-emitting material for an organic EL device represented by the general formula [1] in a light-emitting layer has high emission luminance and excellent stability when repeatedly used. The inventors have found that the present invention has been accomplished.

[0006]

The present invention relates to a luminescent material for an organic electroluminescence device represented by the following general formula [1]. General formula [1]

Embedded image [In the formula, A to H represent an aromatic ring which may have a substituent. ]

The present invention further provides an organic electroluminescent device comprising a light emitting layer or a plurality of organic compound thin films including the light emitting layer formed between a pair of electrodes, wherein the light emitting layer contains the above light emitting material for organic electroluminescent devices. It is an organic electroluminescence element which is a layer.

Further, the present invention is the above-described organic electroluminescent device, wherein a layer containing an aromatic tertiary amine derivative or a phthalocyanine derivative is formed between the light emitting layer and the anode.

Further, the present invention is the above-mentioned organic electroluminescence device, wherein a layer containing a metal complex compound or a nitrogen-containing five-membered ring derivative is formed between the light-emitting layer and the cathode.

BEST MODE FOR CARRYING OUT THE INVENTION

Examples of the aromatic ring A to H which may have a substituent represented by the general formula [1] in the present invention include a benzene ring, a naphthalene ring, an anthracene ring, an azulenyl ring,
There are heptanenyl ring, acenaphthylenyl ring, pyrenyl ring and the like.

The aromatic ring A of the general formula [1] in the present invention
As typical examples of the substituent which may be substituted with to H, there are the following substituents. A hydrogen atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group, a substituted or unsubstituted amino group is shown, and adjacent substituents are bonded to each other. You may form an aromatic ring.

Specific examples of the substituent include fluorine, chlorine, bromine and iodine as the halogen atom, and methyl, ethyl, propyl, butyl and sec-butyl groups as the substituted or unsubstituted alkyl group. tert-butyl group, pentyl group, hexyl group, heptyl group, octyl group, stearyl group, 2-phenylisopropyl group, trichloromethyl group, trifluoromethyl group, benzyl group,
Examples include α, α-dimethylbenzyl group and α, α-methylphenylbenzyl group. Examples of the substituted or unsubstituted alkoxyl group include methoxy group, ethoxy group, propoxy group, n-butoxy group, t-butoxy group, n-octyloxy group, t-octyloxy group, 1,1,1-tetrafluoroethoxy group. Group, phenoxy group and the like. As the substituted or unsubstituted aryl group, a phenyl group, a biphenyl group, a terphenyl group, a 3,5-dichlorophenyl group,
Examples include naphthyl group, anthryl group and pyrenyl group. Examples of the substituted or unsubstituted amino group include an amino group, a dimethylamino group, a diethylamino group, a phenylmethylamino group, a diphenylamino group, a ditolylamino group, a dibenzylamino group, and the like. Further, adjacent substituents are bonded to each other, a phenyl group, a naphthyl group, an anthryl group,
A pyrenyl group, a carbazole group, a phenoxazine group, a phenothiazine group, an acridone group or the like may be formed. In the general formula [1], having a substituent having an aromatic ring,
Alternatively, a compound in which the substituents form an aromatic ring has a high glass transition temperature or melting point temperature, and
When used as a light emitting material for an element, it exhibits high emission brightness and is advantageous against deterioration of the element due to Joule heat even when emitting light for a long time. The compounds of the present invention are not limited to these substituents.

An example of the method for synthesizing the compound represented by the general formula [1] of the present invention is shown below.

The compound of the general formula [1] is synthesized by reacting 9-halogenoanthracene, a diphenylamine derivative which may have a substituent, a base and a catalyst in a solvent.
It can also be synthesized from an anthraquinone derivative instead of the anthracene derivative. As the base, potassium carbonate, sodium carbonate, potassium hydroxide, sodium hydroxide, aqueous ammonia or the like can be used.
Catalysts include copper powder, cuprous chloride, tin, stannous chloride, pyridine, aluminum trichloride or titanium tetrachloride. The solvent may be any solvent having a high boiling point such as nitrobenzene, dimethylformamide, 1,3-dimethyl-2-imidazolidinone, benzene, toluene and xylene. The above synthesis method is not limited.

Representative examples of the compounds of the present invention are shown in Table 1 below, but the present invention is not limited to these representative examples.

[0016]

[Table 1]

[0017]

[0018]

[0019]

[0020]

[0021]

The compound represented by the general formula [1] of the present invention is an excellent light emitting material for an electroluminescence type device since it has little concentration quenching of light emission in a solid state and is stable even when an electric field is applied. . Further, it has good hole injecting property and hole transporting property, and can be effectively used as a hole transporting type light emitting material. Further, other hole transporting material, electron transporting material or doping material may be used in the light emitting layer.

The organic EL element is an element in which a single-layer or multi-layer organic thin film is formed between an anode and a cathode. In the case of the single layer type, a light emitting layer is provided between the anode and the cathode. The light emitting layer contains a light emitting material and may further contain a hole injection material or an electron injection material for transporting holes injected from an anode or electrons injected from a cathode to the light emitting material. The multilayer type includes (anode / hole injection layer / electron injection layer / cathode), (anode / hole injection layer / electron injection layer / cathode), and (anode / hole injection layer / light emission layer / electron injection layer / cathode) multilayer. There is an organic EL element stacked in a configuration. The compound represented by the general formula [1] has high light emitting properties and has hole injecting properties and hole transporting properties, and thus can be used as a hole injecting light emitting material in a light emitting layer.

If necessary, in addition to the compound of the general formula [1] of the present invention, further light emitting materials, doping materials, hole injecting materials and electron injecting materials can be used in the light emitting layer. When the organic EL element has a multilayer structure, it is possible to prevent a decrease in luminance and life due to quenching. If necessary, a combination of a light emitting material, a doping material, a hole injection material, and an electron injection material can be used. Further, it is possible to improve the light emission brightness and the light emission efficiency and obtain light emission from blue to red by using the doping material. Further, the hole injection layer, the light emitting layer, and the electron injection layer are
Each of them may be formed by two or more layers.

As the conductive material used for the anode of the organic EL element, those having a work function larger than 4 eV are suitable, and carbon, aluminum, vanadium, iron, cobalt, nickel, tungsten, silver, gold and platinum are suitable. , Palladium and their alloys, metal oxides such as tin oxide and indium oxide used for ITO substrates and NESA substrates,
Further, an organic conductive resin such as polythiophene or polypyrrole is used. As the conductive material used for the cathode, those having a work function smaller than 4 eV are suitable, and magnesium, calcium, tin, lead, titanium,
Yttrium, lithium, ruthenium, manganese and the like and alloys thereof are used. Alloys include, but are not limited to, magnesium-silver, magnesium-indium, lithium-aluminum, and the like. The anode and the cathode may be formed of two or more layers if necessary.

In the organic EL device, it is desirable that at least one of them is sufficiently transparent in the emission wavelength region of the device in order to emit light efficiently. Further, it is desirable that the substrate is also transparent. The transparent electrode is set using the above-described conductive material so as to secure a predetermined translucency by a method such as vapor deposition or sputtering. The electrode on the light emitting surface desirably has a light transmittance of 10% or more. The substrate is not limited as long as it has mechanical and thermal strength and is transparent, but examples thereof include transparent resins such as a glass substrate, a polyethylene plate, a polyether sulfone plate, and a polypropylene plate. Can be

For forming each layer of the organic EL device according to the present invention, any of dry film forming methods such as vacuum deposition and sputtering and wet film forming methods such as spin coating and dipping can be applied. The film thickness is not particularly limited, but each layer needs to be set to an appropriate film thickness. If the film thickness is too thick, a large applied voltage is required to obtain a constant light output, resulting in poor efficiency. If the film thickness is too small, pinholes and the like are generated, and sufficient light emission luminance cannot be obtained even when an electric field is applied. Normal thickness is 5nm to 10μ
The range of m is suitable, but the range of 10 nm to 0.2 μm is more preferable.

In the case of the wet film forming method, the material forming each layer is ethanol, chloroform, tetrahydrofuran,
The thin film is formed by dissolving or dispersing in a suitable solvent such as dioxane, and any solvent may be used. In any of the organic thin film layers, a suitable resin or additive may be used for improving film forming properties, preventing pinholes in the film, and the like. Resins that can be used include insulating resins such as polystyrene, polycarbonate, polyarylate, polyester, polyamide, polyurethane, polysulfone, polymethylmethacrylate, polymethylacrylate, and cellulose, and photoconductive materials such as poly-N-vinylcarbazole and polysilane. Examples of the resin include conductive resins such as polythiophene and polypyrrole. Examples of the additive include an antioxidant, an ultraviolet absorber, and a plasticizer.

The present organic EL device comprises a light emitting layer, a hole injection layer,
In the electron injection layer, known light emitting materials, doping materials, hole injection materials and electron injection materials can be used if necessary.

As the light emitting material or the doping material which can use the compound of the general formula [1] in the light emitting layer, anthracene, naphthalene, phenanthrene, pyrene, tetracene, coronene, chrysene, fluorescein, perylene,
Phthaloperylene, naphthaloperylene, perinone, phthaloperinone, naphthaloperinone, diphenylbutadiene,
Tetraphenylbutadiene, coumarin, oxadiazole, aldazine, bisbenzoxazoline, bisstyryl, pyrazine, cyclopentadiene, quinoline metal complex, aminoquinoline metal complex, benzoquinoline metal complex, imine, diphenylethylene, vinylanthracene, diaminocarbazole, pyran Thiopyran, polymethine, merocyanine, imidazole chelated oxinoid compounds, quinacridone, rubrene, and fluorescent dyes, but are not limited thereto.

The hole-injecting material has the ability to transport holes, has a hole-injecting effect from the anode, and has an excellent hole-injecting effect on the light-emitting layer or the light-emitting material. Examples thereof include compounds that prevent excitons from moving to the electron injection layer or the electron injection material and have excellent thin film forming ability. Specifically, phthalocyanine derivatives, naphthalocyanine derivatives, porphyrin derivatives, oxazole, oxadiazole, triazole, imidazole, imidazolone, imidazolethione, pyrazoline, pyrazolone,
Tetrahydroimidazole, oxazole, oxadiazole, hydrazone, acylhydrazone, polyarylalkane, stilbene, butadiene, benzidine-type triphenylamine, styrylamine-type triphenylamine, diamine-type triphenylamine, and derivatives thereof, and polyvinyl carbazole , Polysilane, and a polymer material such as a conductive polymer, but are not limited thereto.

In the organic EL device of the present invention, a more effective hole injection material is an aromatic tertiary amine derivative or a phthalocyanine derivative. Specifically, examples of the aromatic tertiary amine derivative include triphenylamine, tolylamine, tolylphenylamine, N, N′-diphenyl-N, N ′-(3-methylphenyl) -1,1 ′.
-Biphenyl-4,4'-diamine, N, N, N'N '
-(4-methylphenyl) -1,1′-phenyl-4,
4′-diamine, N, N, N′N ′-(4-methylphenyl) -1,1′-biphenyl-4,4′-diamine,
N, N'-diphenyl-N, N'-dinaphthyl-1,
1'-biphenyl-4,4'-diamine, N, N'-
(Methylphenyl) -N, N ′-(4-n-butylphenyl) -phenanthrene-9,10-diamine, N, N
Examples include, but are not limited to, -bis (4-di-4-tolylaminophenyl) -4-phenyl-cyclohexane and the like, and oligomers and polymers having an aromatic tertiary amine skeleton. As phthalocyanine (Pc) derivatives, H ₂ Pc, CuPc, C
oPc, NiPc, ZnPc, PdPc, FePc, M
nPc, ClAlPc, ClGaPc, ClInPc,
ClSnPc, Cl ₂ SiPc, (HO) AlPc,
(HO) GaPc, VOPc, TiOPc, MoOP
c, a phthalocyanine derivative such as GaPc-O-GaPc, a naphthalocyanine derivative, and the like, but are not limited thereto.

The electron injecting material has an ability to transport electrons, has a hole injecting effect from the cathode, and an excellent electron injecting effect to the light emitting layer or the light emitting material. Examples thereof include compounds that prevent migration to the hole injection layer and have excellent thin film forming ability. For example, fluorenone, anthraquinodimethane, diphenoquinone, thiopyran dioxide, oxazole, oxadiazole, triazole, imidazole, perylenetetracarboxylic acid, fluorenylidenemethane, anthraquinodimethane,
Examples include, but are not limited to, anthrones and derivatives thereof. It is also possible to sensitize by adding an electron accepting material to the hole injecting material and an electron donating material to the electron injecting material.

In the organic EL device of the present invention, a more effective electron injection material is a metal complex compound or a nitrogen-containing five-membered ring derivative. Specifically, as the metal complex compound, lithium 8-hydroxyquinolinate, bis (8
-Hydroxyquinolinato) zinc, bis (8-hydroxyquinolinato) copper, bis (8-hydroxyquinolinato) manganese, tris (8-hydroxyquinolinato)
Aluminum, tris (2-methyl-8-hydroxyquinolinato) aluminum, tris (8-hydroxyquinolinato) gallium, bis (10-hydroxybenzo [h] quinolinato) beryllium, bis (10-hydroxybenzo [h] (Quinolinato) zinc, bis (2-methyl-8-quinolinato) chlorogallium, bis (2-methyl-8-quinolinato) (o-cresolate) gallium, bis (2-methyl-8-quinolinato) (1-naphtholate) aluminum , Bis (2-methyl-8-quinolinato) (2-naphtholate) gallium and the like,
It is not limited to these. As the nitrogen-containing five-membered derivative, an oxazole, thiazole, oxadiazole, thiadiazole or triazole derivative is preferable. Specifically, 2,5-bis (1-phenyl)
-1,3,4-oxazole, dimethyl POPOP,
2,5-bis (1-phenyl) -1,3,4-thiazole, 2,5-bis (1-phenyl) -1,3,4-oxadiazole, 2- (4′-tert-butylphenyl) ) -5- (4 "-biphenyl) 1,3,4-oxadiazole, 2,5-bis (1-naphthyl) -1,3,4
-Oxadiazole, 1,4-bis [2- (5-phenyloxadiazolyl)] benzene, 1,4-bis [2-
(5-phenyloxadiazolyl) -4-tert-butylbenzene], 2- (4'-tert-butylphenyl) -5- (4 "-biphenyl) -1,3,4-thiadiazole, 2,5- Bis (1-naphthyl) -1,3,4
-Thiadiazole, 1,4-bis [2- (5-phenylthiadiazolyl)] benzene, 2- (4'-tert-
(Butylphenyl) -5- (4 "-biphenyl) -1,
3,4-triazole, 2,5-bis (1-naphthyl)
-1,3,4-triazole, 1,4-bis [2- (5
-Phenyltriazolyl)] benzene and the like, but are not limited thereto.

In the organic EL device of the present invention, in addition to the compound of the general formula [1], at least one of a light emitting material, a doping material, a hole injecting material and an electron injecting material may be contained in the same layer. In order to improve the stability of the organic EL device obtained according to the present invention with respect to temperature, humidity, atmosphere, etc., a protective layer is provided on the surface of the device, or silicon oil or the like is sealed to protect the entire device. It is also possible.

As described above, since the compound of the general formula [1] is used for the organic EL device in the present invention, the luminous efficiency and the luminous brightness can be increased. In addition, this device is extremely stable against heat and current, and furthermore, it can emit light that can be practically used at a low driving voltage, so that the deterioration, which has been a major problem until now, can be significantly reduced. Was completed.

The organic EL device of the present invention can be used as a flat panel display such as a wall-mounted television or a flat light-emitting body.
It is applied to light sources such as copiers and printers, light sources such as liquid crystal displays and instruments, display boards, and marker lights, and its industrial value is extremely large.

The material of the present invention can also be used in the fields of organic EL devices, electrophotographic photoreceptors, photoelectric conversion devices, solar cells, image sensors and the like.

[0039]

EXAMPLES The present invention will be described in detail below based on examples. The term "parts" in this example means "parts by weight". Method for synthesizing compound (3) 1,4-cyclohexanedione 16 was added to 30 parts of acetic acid.
Part, 4,4-dimethyltriphenylamine (48 parts) and methanesulfonic acid (2 parts) were added, and the mixture was stirred at 105 ° C. for 30 hours. Thereafter, the mixture was diluted with 500 parts of water and neutralized with a dilute aqueous sodium hydroxide solution. Then, extraction was performed with ethyl acetate, the mixture was concentrated, and purified by column chromatography using silica gel to obtain 31 parts of fluorescent powder. As a result of molecular weight analysis, it was confirmed to be compound (3). The results of elemental analysis of the product are shown below. Elemental analysis result Calculated value as C ₈₆ H ₇₆ N ₄ (%): C: 88.66 H: 6.53 N: 4.81 Experimental value (%): C: 88.49 H: 6.57 N: 4 .94 The infrared absorption spectrum (KBr tablet method) of this compound is shown in FIG.

[0040]

FIG.

Example 1 On a washed glass plate with an ITO electrode, the compound (2),
2,5-bis (1-naphthyl) -1,3,4-oxadiazole and polycarbonate resin (Teijin Kasei: Panlite K-1300) are dissolved in tetrahydrofuran at a ratio of 2: 3: 5, and spin coating is performed. 10
A light emitting layer of 0 nm was obtained. An electrode having a thickness of 150 nm was formed thereon with an alloy of magnesium and silver mixed at a ratio of 10: 1 to obtain an organic EL device. This device has an emission luminance of 85 (cd / m ² ) at a DC voltage of 5 V and a maximum emission luminance of 8600.
Light emission with (cd / m ² ) and a luminous efficiency of 0.9 (lm / W) was obtained.

Example 2 Compound (6) was dissolved in methylene chloride on a washed glass plate with an ITO electrode, and a hole-transporting light-emitting layer having a thickness of 50 nm was obtained by spin coating. Then, tris (8-quinolinato) aluminum complex (Alq3)
Was vacuum-deposited to form an electron injection layer having a film thickness of 10 nm, and an electrode having a film thickness of 100 nm was formed on the electron injection layer having an alloy of magnesium and silver mixed at a ratio of 10: 1 to obtain an organic EL device.
The hole injection layer and the light emitting layer are formed in a vacuum of 10 ^-6 Torr,
The deposition was performed at a substrate temperature of room temperature. This device has a light emission brightness of 220 (cd / m ² ) at a DC voltage of 5 V, a maximum light emission brightness of 13500 (cd / m ² ), and a light emission efficiency of 1.3 (lm / m ² ).
Light emission of W) was obtained.

Example 3 Compound (17) was applied onto a washed glass plate with an ITO electrode.
Was vacuum-deposited to form a hole injection layer having a film thickness of 40 nm. Then, the compound (3) is vacuum-deposited to a film thickness of 40 nm.
Was formed into a light emitting layer, and Alq3 was further vacuum-deposited to form an electron injection layer having a film thickness of 40 nm. On top of that, an alloy in which magnesium and silver were mixed at a ratio of 10: 1 to a thickness of 100 nm.
Was formed to obtain an organic EL device. Each thin film layer is 1
Deposition was carried out in a vacuum of 0 ^-6 Torr at a substrate temperature of room temperature. This device has an emission luminance of 330 (c
d / m ² ), maximum emission brightness 15000 (cd / m ² ),
Light emission with a luminous efficiency of 1.6 (lm / W) was obtained.

[0044]

Embedded image Compound (17)

Examples 4 to 19 A compound (18) represented by the following chemical structure was vacuum-deposited on a washed glass plate with an ITO electrode to give a film thickness of 40 nm.
Was obtained. Next, the compounds shown in Table 2 were vacuum-deposited as light-emitting materials to obtain a light-emitting layer having a thickness of 40 nm. Further, a compound (19) represented by the following chemical structure is vacuum-deposited to form an electron injection layer having a thickness of 40 nm, and an alloy in which magnesium and silver are mixed at a ratio of 10: 1 has a thickness of 150.
An electrode having a thickness of nm was formed to obtain an organic EL device. Each layer was vapor-deposited under a vacuum of 10 ⁻⁶ Torr and a substrate temperature of room temperature. Table 2 shows the light emission characteristics of this device. The light emission luminance in Table 2 is the luminance when a DC voltage of 5 V is applied, and all the organic EL elements of this example were highly efficient light emitting elements.

[0046]

Embedded image Compound (18)

[0047]

Embedded image Compound (19)

[0048]

[Table 2]

Example 20 Compound (18) was applied onto a washed glass plate with an ITO electrode.
Was vacuum-deposited to obtain a hole injection layer having a thickness of 40 nm. Then, the compound (14) was vacuum-deposited as a light emitting material to obtain a light emitting layer having a film thickness of 40 nm. Further, 2,5-bis (1
-Naphthyl) -1,3,4-oxadiazole was vacuum-deposited to obtain an electron injection layer having a film thickness of 40 nm. in addition,
An alloy of magnesium and silver mixed at a ratio of 10: 1 with a film thickness of 15
An 0 nm electrode was formed to obtain an organic EL device. This device has an emission luminance of 780 (cd / m ² ) at a DC voltage of 5V,
Maximum luminous brightness 24600 (cd / m ² ), luminous efficiency 2.
Light emission of 9 (lm / W) was obtained.

Example 21 Example 2 except that Alq3 is used as the electron injection layer.
An organic EL device was produced by the same method as in Example 0. The device showed a light emission brightness of 720cd / m ² at a direct current voltage 5V, maximum radiance 23300 (cd / m ^2), luminous efficiency 2.4
Light emission of (lm / W) was obtained.

Example 22 An organic EL device was manufactured in the same manner as in Example 4 except that a hole-injecting layer having a film thickness of 5 nm of metal-free phthalocyanine was provided between the ITO electrode and the compound (18) by vacuum evaporation. Was produced. This device has an emission luminance of 850 at a DC voltage of 5V.
cd / m ² , maximum emission brightness 21300 (cd / m ² ),
Light emission with a light emission efficiency of 2.8 (lm / W) was obtained. Compared with the organic EL element of Example 20, there is an advantage that the luminance at the time of low voltage light emission of 5 V or less is high.

Comparative Example 1 Compound (18) was placed on a washed glass plate with an ITO electrode.
Was vacuum-deposited to form a hole injection layer having a film thickness of 50 nm. Then, Alq3 was vacuum-deposited to form an electron injection type light emitting layer having a film thickness of 50 nm. An electrode having a film thickness of 100 nm was formed thereon with an alloy in which magnesium and silver were mixed at a ratio of 10: 1 to obtain an organic EL element. Each thin film layer is 10 ^-6 To
Deposition was performed in a vacuum of rr at a substrate temperature of room temperature. This device has a luminance of 15 (cd / cd) at a DC voltage of 5V.
m ² ), maximum emission luminance of 12000 (cd / m ² ), and emission efficiency of 1.1 (lm / W).

The organic EL device shown in this embodiment has a maximum emission luminance of 10,000 c in the device structure of three layers or more.
Light emission of d / m ² or more was obtained, and high luminous efficiency was obtained in all cases. When the organic EL device shown in this example was continuously emitted at 3 mA / cm ² ,
It was possible to observe the luminance of more than half of the initial emission luminance over the time. However, when the organic EL device of Comparative Example 1 was made to emit light under the same conditions, the brightness was reduced to less than half the initial emission brightness in 500 hours or less. This is because the light emitting material represented by the general formula [1] of the present invention has an extremely high fluorescence quantum efficiency, and thus a device using this light emitting material can achieve high-luminance light emission in a low current region. It is considered that the life of the device can be improved. The organic EL device of the present invention achieves improvement in luminous efficiency, luminous brightness and long life, and is used together with a light emitting material, a doping material, a hole injecting material, an electron injecting material, a sensitizer and a resin. There is no limitation on the electrode material, etc. and the method for manufacturing the element.

[0054]

According to the organic EL device using the organic EL device material of the present invention as a light-emitting material, the device emits light with high luminous efficiency and high luminance as compared with the prior art, and a long-life organic EL device can be obtained. .

[Brief description of the drawings]

1] Infrared absorption spectrum of Compound 3

Claims (4)

[Claims] 1. A light-emitting material for an organic electroluminescence device represented by the following general formula [1]. General formula [1] [In the formula, A to H represent an aromatic ring which may have a substituent. ] 2. An organic electroluminescence device comprising a light emitting layer or a plurality of organic compound thin films including a light emitting layer formed between a pair of electrodes, wherein the light emitting layer comprises the light emitting material for an organic electroluminescence device according to claim 1. An organic electroluminescent element which is a layer containing. 3. The organic electroluminescence device according to claim 2, wherein a layer containing an aromatic tertiary amine derivative or a phthalocyanine derivative is formed between the light emitting layer and the anode. 4. The organic electroluminescence device according to claim 2, wherein a layer containing a metal complex compound or a nitrogen-containing five-membered ring derivative is formed between the light emitting layer and the cathode.