JP3409356B2 - Organic electroluminescence device - Google Patents

Description

Detailed Description of the Invention

[0001]

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

[0002]

2. Description of the Related Art An EL element using an organic substance is expected to be used as a solid-state light emitting type inexpensive large area full color display element, and many developments have been made. Generally EL element
The child is composed of a light emitting layer and a pair of counter electrodes sandwiching the light emitting 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 , the electrons recombine with the holes in the light emitting layer, and the energy level becomes the conduction band. This is a phenomenon in which energy is emitted as light when returning from the valence band to the valence band.

A conventional organic EL element has a higher driving voltage and lower emission brightness and emission efficiency than an inorganic EL element.
In addition, the deterioration of the characteristics was remarkable and it was not put to practical use.
In recent years, an organic EL in which thin films containing an organic compound having a high fluorescence quantum efficiency that emits light at a low voltage of 10 V or less are laminated
The device has been reported and is of great interest (see Applied Physics Letters, 51, 913, 1987). In this method, the metal chelate complex is added to the phosphor layer,
High-luminance green light emission is obtained by using an amine compound in the hole injection layer, and the luminance is several hundreds at a DC voltage of 6 to 7V.
It has cd / m ² and a maximum luminous efficiency of 1.5 lm / W, which is close to the practical range. However,
The organic EL devices to date have been improved in emission intensity due to the improved structure, but have not yet had sufficient emission brightness. Further, it has a big problem that it is inferior in stability when repeatedly used. Therefore, under the present circumstances, it is desired to develop an organic EL device having a larger emission brightness and excellent stability in repeated use.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide an organic EL device having a large emission intensity and excellent stability in repeated use. As a result of diligent studies by the present inventors, they found that an organic EL element using an organic compound represented by the general formula [2] has high emission intensity and excellent stability during repeated use. Invented.

[0005]

Means for Solving the Problems That is, the first invention, the lower
Organic electroluminescence represented by general formula [2]
It is a light-emitting material of the device .

[0006]

General formula [2]

[Chemical 4]

[ Wherein A ² is O, S, Se, Te, N
R ²⁵ , PR ²⁶ , SO ₂ , CH ₂ , CH = CH, C = C (C
N) ₂ , C = X, CR ²⁸ R ²⁹ , and B ² is O, S, S
e, Te, NR ²⁵ , PR ²⁶ , CH ₂ , CH = CH, CR
²⁸ R ²⁹ is shown. A ² or B ² is A ² or
It may be directly bonded without interposing B ² . This
Here, R ⁹ to R ²⁹ are each independently a hydrogen atom,
Halogen atom, cyano group, nitro group, amino group, ester group, mono- or di-substituted amino group, acylamino group, hydroxyl group, alkoxy group, mercapto group, alkyloxy group, alkylthio group, aryloxy group, arylthio group, siloxy group, Acyl group, cycloalkyl group, carbamoyl group, carboxylic acid group, sulfonic acid group, substituted or unsubstituted aliphatic group, substituted or unsubstituted aliphatic ring group, substituted or unsubstituted carbocyclic aromatic ring group Represents a substituted or unsubstituted heterocyclic aromatic ring group or a substituted or unsubstituted heterocyclic group . X is to table <br/> O, S, Se, and Te. ]

[0009] The second invention is an organic electroluminescence element having a luminescent layer of an organic compound thin film of the pair of electrodes between the one or more layers, the light-emitting layer
The organic electroluminescence device in which the light emitting material contained is the above light emitting material .

Examples of the group of the compound represented by the general formula [2] and the substituent atom or substituent to be added to the group in the present invention include a hydrogen atom, a halogen atom, a cyano group, a nitro group, an amino group, Carboxy group, sulfone group, amino group, acylamino group, ester group, mono- or di-substituted amino group, alkoxy group, mercapto group, or methyl group, ethyl group, propyl group, butyl group, sec
-Butyl group, tert-butyl group, pentyl group, hexyl group, heptyl group, octyl group, stearyl group, trichloromethyl group, aminomethyl group, acetoxymethyl group, acetoxyethyl group, acetoxypropyl group,
Acetoxybutyl group, hydroxymethyl group, hydroxylethyl group, hydroxylpropyl group, hydroxylbutyl group, vinyl group, styryl group, acetylene group, alkoxy group, mercapto group, alkyloxy group, alkylthio group, aryloxy group, arylthio group, A substituent such as a siloxy group, an acyl group, a cycloalkyl group, a carbamoyl group and a substituted or unsubstituted acyclic hydrocarbon group,
Cyclopropyl group, cyclohexyl group, 1,3-cyclohexadienyl group, 2-cyclopenten-1-yl group,
2,4-Cyclopentadiene-1-yridenyl group, phenyl group, biphenylenyl group, triphenylenyl group, tetraphenylenyl group, 2-methylphenyl group, 3-nitrophenyl group, 4-methylthiophenyl group, 3,5-dicyano A substituted or unsubstituted monocyclic hydrocarbon group such as phenyl group, o-, m- and p-tolyl group, xylyl group, o-, m- and p-cumenyl group, mesityl group, pentalenyl group, indenyl group, Naphthyl group, azulenyl group, heptanenyl group, acenaphthylenyl group, phenalenyl group,
Fluorenyl group, anthryl group, anthraquinonyl group,
3-methylanthryl group, phenanthryl group, triphenylenyl group, pyrenyl group, chrysenyl group, 2-ethyl-
1-chrysenyl group, picenyl group, perylenyl group, 6-chloroperylenyl group, pentaphenyl group, pentacenyl group, tetraphenylenyl group, hexaphenyl group, hexacenyl group, rubicenyl group, coronenyl group, trinaphthylenyl group, heptaphenyl group, heptaenyl Group, pyrantrenyl group, substituted or unsubstituted fused polycyclic hydrocarbon such as ovarenyl group, thienyl group, furyl group, pyrrolyl group,
Imidazolyl group, pyrazolyl group, pyridyl group, pyrazinyl group, pyrimidinyl group, pyridazinyl group, indolyl group, quinolyl group, isoquinolyl group, phthalazinyl group, quinoxalinyl group, quinazolinyl group, carbazolyl group, acridinyl group, phenazinyl group, furfuryl group, isothiazolyl group , Isoxazolyl group, flazanyl group, phenoxazinyl group, benzothiazolyl group, benzoxazolyl group, benzimidazolyl group, 2-methylpyridyl group,
Substituted or unsubstituted heterocyclic group such as 3-cyanopyridyl group or substituted or unsubstituted aromatic vinyl group, hydroxyl group, methoxy group, ethoxy group, propoxy group, butoxy group, sec-butoxy group, tert-butoxy group Group, pentyloxy group, hexyloxy group, stearyloxy group, phenoxy group, methylthio group, ethylthio group, propylthio group, butylthio group, sec-butylthio group, t
ert-butylthio group, pentylthio group, hexylthio group, heptylthio group, octylthio group, phenylthio group, amino group, methylamino group, dimethylamino group, ethylamino group, diethylamino group, dipropylamino group, dibutylamino group, diphenylamino group , Bis (acetooxymethyl) amino group, bis (acetooxyethyl) amino group, bis (acetooxypropyl) amino group, bis (acetooxybutyl) amino group, dibenzylamino group, methylsulfamoyl group, dimethylsulfate Famoyl group, ethylsulfamoyl group, diethylsulfamoyl group, propylsulfamoyl group, butylsulfamoyl group, phenylsulfamoyl group, diphenylsulfamoyl group, methylcarbamoyl group, dimethylcarbamoyl group, ethylcarbamoyl group -Yl group, diethylcarbamoyl group, propylcarbamoyl group, butylcarbamoyl group, phenylcarbamoyl group, methylcarbonylamino group, ethylcarbonylamino group, propylcarbonylamino group, butylcarbonylamino group, phenylcarbonylamino group, methoxycarbonylamino group, ethoxy Carbonylamino group, propoxycarbonylamino group, butoxycarbonylamino group, phenoxycarbonyl group,
2- (2-ethoxyethoxy) ethoxy group, 2- (2-
Ethoxyethoxy) ethylthio group, 2- [2- (2-methoxyethoxy) ethoxy] ethylthio group and the like,
It is not limited to these substituents.

The type, number, and position of the substituent atom or substituent in the compound of the general formula [2] used in the present invention are not particularly limited. The compound of the general formula [2] of the present invention is generally a ring-closing method using an acidic reagent of diphenylamine-2-carboxylic acid, and a synthetic method by dimerization thereof (Org. Syn. Col. Vol. 2, (See P15). Other than this, there are synthesis from salicylic acid anilide and anthranilic acid anilide, photochemical reaction from acridine-N-oxide and acetic anhydride, ring formation from N-substituted aromatic amine, n-butyllithium, and carbon dioxide. . Moreover, mutual conversion of acridone, acridine, acridan, and substituted acridine can be easily performed. Representative examples of the compound of the general formula [2] used in the present invention are specifically shown in Table 1 below, but the present invention is not limited to the following representative examples.

[0012]

[0013]

[0014]

Table 1

[0016]

1 to 3 show the organic EL used in the present invention.
An example of a schematic view of the device is shown. In the figure, generally, the electrode A 2 is an anode, and the electrode B 6 is a cathode. In addition to these layer configurations, there is an organic EL element in which (electrode A / light emitting layer / electron injection layer / electrode B) is laminated in this order,
The compound of the general formula [2] can be preferably used also in this device structure. The compounds of the general formula [2], since it has combined strong luminescence with large carrier transport capability, the luminescent material in the light emitting layer 4, can be used as a light emitting adjuvant.

In the light emitting layer 4 of FIG. 1, if necessary, in addition to the compound of the general formula [2] of the present invention, a light emitting substance, a light emission assisting material, a hole transporting material for carrying carriers and an electron transporting material. Can also be used. In the structure of FIG. 2, the light emitting layer 4 and the hole injection layer 3 are separated. With this structure, the hole injection efficiency from the hole injection layer 3 to the light emitting layer 4 is improved, and the light emission brightness and the light emission efficiency can be increased. in this case,
For light emission efficiency, it is desirable that the light emitting material used in the light emitting layer itself has an electron transporting property or that the light emitting layer has an electron transporting property by adding an electron transporting material.

The structure of FIG. 3 has an electron injection layer 5 in addition to the hole injection layer 3 to improve the efficiency of recombination of holes and electrons in the light emitting layer 4. As described above, by forming the organic EL element into a multi-layer structure, it is possible to prevent a decrease in brightness and life due to quenching. Also in the elements of FIGS. 2 and 3, if necessary, a light emitting substance, a light emission auxiliary material, a hole transporting material for carrier transport, and an electron transporting material can be used in combination.

As the conductive material used for the anode of the organic EL device, those having a work function larger than 4 eV are preferable, and carbon, aluminum, vanadium, iron, cobalt, nickel, tungsten, silver, gold, platinum. , Palladium and their alloys, ITO substrates, metal oxides such as tin oxide and indium oxide called NESA substrates, and organic conductive resins such as polythiophene and polypyrrole are used. As the conductive material used for the cathode, one having a work function smaller than 4 eV is suitable, and magnesium, calcium, tin, lead, titanium,
Yttrium, lithium, ruthenium, manganese and the like and alloys thereof are used, but not limited to these.

In the organic EL device, it is desirable that at least one of the electrode A shown by 2 and the electrode B shown by 6 is sufficiently transparent in the emission wavelength region of the device in order to emit light efficiently. Further, it is desirable that the substrate 1 is also transparent. The transparent electrode is made of the above-mentioned conductive material and is set by a method such as vapor deposition or sputtering so as to ensure a predetermined translucency. The electrode that takes out the emitted light is
It is desirable that the light transmittance is 10% or more.

The substrate 1 is not limited as long as it has mechanical and thermal strength and is transparent, but examples thereof include a glass substrate, a polyethylene plate, a polyether sulfone plate, and a polypropylene plate. Examples include transparent resins.
For forming each layer of the organic EL element according to the present invention, any method such as a dry film forming method such as vacuum deposition and sputtering, or a wet film forming method 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 thin, pinholes and the like will occur, and even if an electric field is applied, sufficient emission brightness cannot be obtained. A typical film thickness is in the range of 10 nm to 10 μm, preferably 100 Å to 2000
It is in the Angstrom range.

In the case of the wet film forming method, a thin film is formed by using a liquid in which the material forming each layer is dissolved or dispersed in an appropriate solvent such as chloroform, tetrahydrofuran or dioxane, and which solvent is used. May be. Further, in any of the organic layers, an appropriate resin or additive may be used in order to improve the film-forming property and prevent pinholes in the film. Examples of such a resin include insulating resins such as polystyrene, polycarbonate, polyarylate, polyester, polyamide, polysulfone, polymethylmethacrylate, and polymethylacrylate; photoconductive resins such as poly-N-vinylcarbazole and polysilane; and polythiophene. Examples thereof include conductive resins such as polypyrrole.

This organic EL device comprises a light emitting layer, a hole injection layer,
In the electron injection layer, if necessary, in addition to the compound of the general formula [2] , a known light emitting substance, light emission auxiliary material, hole transport material, or electron transport material can be used. In that case, the compound of the general formula [2] is used as a main light-emitting substance and is doped with a known light emission auxiliary material described below, or the compound of the general formula [2] is used as a main light-emitting substance and is doped with a compound of the general formula [2]. Thus, it is possible to obtain an organic EL element having appropriate emission brightness and emission wavelength. The doping amount of the light emission assisting material varies depending on each material and may be any amount.
A doping amount of 10 to 10 parts by weight is desirable.

Known luminescent substances or auxiliary substances for luminescent substances include anthracene, naphthalene, phenanthrene, pyrene, tetracene, coronene, chrysene, fluorescein, perylene, phthaloperylene, naphthaloperylene, perinone, phthaloperinone, naphthaloperinone, diphenylbutadiene, tetraphenylbutadiene. , Coumarin, oxadiazole, aldazine, bisbenzoxazoline, bisstyryl, pyrazine, cyclopentadiene, oxine, aminoquinoline, imine, diphenylethylene, vinylanthracene, diaminocarbazole,
Examples include, but are not limited to, pyran, thiopyran, polymethine, merocyanine, imidazole chelated oxinoid compounds, quinacridone and the like and their derivatives.

The hole-transporting material has the ability to transport holes, has an excellent hole-injecting effect on the light-emitting layer or the light-emitting substance, and has an electron-injecting layer or electrons for excitons generated in the light-emitting layer. Examples thereof include compounds that prevent migration to transport materials and have excellent thin film forming ability. Specifically, phthalocyanine compounds, naphthalocyanine compounds, porphyrin compounds, oxadiazole, triazole, imidazole, imidazolone, imidazolethione, pyrazoline, pyrazolone, tetrahydroimidazole, oxazole, oxadiazole, hydrazone, acylhydrazone, poly Aryl alkane, stilbene, butadiene,
Benzidine-type triphenylamine, styrylamine-type triphenylamine, diamine-type triphenylamine, and their derivatives, and polyvinylcarbazole,
There are polymer materials such as polysilane and conductive polymers,
It is not limited to these.

The electron-transporting material has an electron-transporting ability, has an excellent electron-injecting effect on the light-emitting layer or the light-emitting substance, and is a hole-injecting layer or hole-transporting layer of excitons generated in the light-emitting layer. Examples thereof include compounds that prevent transfer to the material and have excellent thin film forming ability. For example, fluorenone, anthraquinodimethane, diphenylquinone, thiopyran dioxide, oxadiazole, perylene tetracarboxylic acid, fluorenylidene methane, anthraquinodimethane,
Examples include, but are not limited to, anthrone and derivatives thereof. It is also possible to sensitize by adding an electron accepting substance to the hole transporting material and adding an electron donating substance to the electron transporting material.

In the organic EL device shown in FIGS. 1, 2 and 3, the compound of the general formula [2] can be used in the light emitting layer, and the light emitting substance, the light emission auxiliary material, the hole transporting material and the electron transporting material. At least 1 type of may be contained in the same layer. Further, in order to improve the stability of the organic EL element obtained by the present invention against temperature, humidity, atmosphere, etc., a protective layer is provided on the surface of the element or silicon oil or the like is enclosed to protect the entire element. It is also possible. As described above, in the present invention, since the compound of the general formula [2] is used for the organic EL device, the luminous efficiency and the luminous brightness can be increased.
Also, this element is very stable against heat and current,
Furthermore, since a practically usable emission brightness can be obtained with a low driving voltage, deterioration, which has been a big problem up to now, can be significantly reduced. The organic EL device of the present invention is
It can be applied to flat panel displays such as wall-mounted televisions and flat light emitters as light sources for copiers and printers, light sources for liquid crystal displays and instruments, display boards, marker lights, etc., and its industrial value is extremely high. large.

[0029]

The present invention will be described in more detail based on the following examples. In the examples, “part” means “part by weight”. (Synthesis example )

Synthesis of Compound (22) In a flask, N-methyl-9-hydroacridine 1 was added.
Add 9.5 parts, N-bromosuccinimide 17.8 parts, benzoyl peroxide 3 parts, and carbon tetrachloride 300 parts, and heat at 60 ° C. for 5 hours. The obtained compound was filtered and washed with water to obtain 16.3 parts of the compound. As a result of chemical analysis, 9
It was confirmed to be -hydro-9-bromo-N-methylacridine. Then, in the flask, 9-hydro-9-
Add 10 parts of bromo-N-methylacridine, 7.1 parts of N-methylacridone, and 30 parts of triethylphosphite, and heat at 100 ° C. for 10 hours. The obtained compound was filtered and washed with water to obtain 12.6 parts of the compound. As a result of chemical analysis, it was confirmed to be compound (22).

[0031]

[0032]

[0033]

[0034]

Example 1 N, N'-diphenyl-N, N '-(3-methylphenyl) -1,1'-on a cleaned glass plate with ITO electrodes
Vacuum deposition of biphenyl-4,4'-diamine to give 30
A hole injection layer having a film thickness of 0 angstrom was obtained. Then, a light emitting layer having a film thickness of 500 angstroms of the compound (23) was formed by a vacuum deposition method, and an electrode having a film thickness of 1500 angstroms was formed on the light emitting layer with an alloy in which magnesium and silver were mixed at a ratio of 10: 1. The organic EL device shown in 2 was obtained. The hole injecting layer and the light emitting layer were vapor-deposited in a vacuum of 10 ⁻⁶ Torr at a substrate temperature of room temperature. The device emitted light of about 190 cd / m ² at a DC voltage of 10 V. From this result, it is understood that the compound of the present invention is a light-emitting substance which transports electrons.

[0036]

Comparative Example 1 Instead of the compound (23), the following compound (2
Organic EL was manufactured in the same manner as in Example 1 except that 6) was used.
A device was produced. The organic film was not transparent but cloudy. This
Element has a luminance of 80 cd / m ² at a DC voltage of 10 V.
Was obtained, but the surface emission was not uniform. Example 2 On a washed glass plate with an ITO electrode, the compound (25)
Dissolved and dispersed in chloroform, spin coating
The light emitting layer is formed by the method of 500 angstrom
A light emitting layer having a film thickness was obtained. On top of that, add 1 magnesium and 1 silver
1500 angstrom film with 0: 1 mixed alloy
A thick electrode was formed to obtain the organic EL device shown in FIG. This
Device emits light of about 25 cd / m ² at a DC voltage of 10 V.
Was obtained. Example 3 On a washed glass plate with an ITO electrode, the compound (22)
Of the organic EL device by forming the light emitting layer of
Was produced. The light emitting layer is the substrate in a vacuum of 10 ^-6 Torr.
Deposition was carried out under the conditions of temperature and room temperature. On top of that, magnesium
1500 angstrom with alloy of 10: 1 and silver
To form an electrode having a film thickness of
Obtained. This element is approximately 45 cd / m ² at a DC voltage of 10 V.
Luminescence was obtained. Example 4 A compound (2
4), N, N'-diphenyl-N, N '-(3-methylphenyl)
Phenyl) -1,1'-biphenyl-4,4'-diamine,
Poly-N-vinylcarbazole was added at a ratio of 3: 2: 5.
Dissolve and disperse in loroform and apply to spin coating method
As a result, a light emitting layer having a film thickness of 500 Å was obtained. So
On top of the alloy with a 10: 1 mixture of magnesium and silver
An electrode having a film thickness of 1500 angstroms is formed, and the structure shown in FIG.
The organic EL device shown in was obtained. This element has a DC voltage of 10
A light emission of about 80 cd / m ² was obtained at V. Example 5 On a washed glass plate with an ITO electrode, N, N'-Zif
Phenyl-N, N '-(3-methylphenyl) -1,1'-
Vacuum deposition of biphenyl-4,4'-diamine to give 30
A hole injection layer having a film thickness of 0 angstrom was obtained. Next
Then, the film thickness of the compound (21) is 500 on by the vacuum deposition method.
Create a luminescent layer of gström and place magnesium on it.
1500 angst with a 10: 1 mixed alloy of silver and silver
An organic EL device shown in FIG. 2 in which an electrode having a film thickness of ROHM is formed.
Got The hole injection layer and the light emitting layer are true of 10 ⁻⁶ Torr.
Vapor deposition was performed in the air at a substrate temperature of room temperature. This element
Is capable of emitting light of about 150 cd / m ² at a DC voltage of 10 V.
It was From this result, the compound of the present invention performs electron transport.
It turns out that it is a luminescent substance. Example 6 On a washed glass plate with an ITO electrode, N, N'-Zif
Phenyl-N, N '-(3-methylphenyl) -1,1'-
Vacuum deposition of biphenyl-4,4'-diamine to give 30
A hole injection layer having a film thickness of 0 angstrom was obtained. Next
Then, tris (8-aluminum quinolino
Ru) complex and compound (22) at a ratio of 20: 1.
Co-deposition in a vacuum of 10 ^-6 Torr and film thickness of 500 Å
Create a luminescent layer of strom and put magnesium on it
1500 ang straw with a 10: 1 mixture of silver
By forming an electrode having a film thickness of
Obtained. This device has a DC voltage of 10 V and a voltage of about 340 cd / m ^2.
Luminescence was obtained. Comparative Example 2 N, N'-Zif
Phenyl-N, N '-(3-methylphenyl) -1,1'-
Vacuum deposition of biphenyl-4,4'-diamine to give 30
A hole injection layer having a film thickness of 0 angstrom was obtained. Next
Then, tris (8-aluminum quinolino
Film) to a film thickness of 5 by co-evaporating the complex) in a vacuum of 10 ⁻⁶ Torr.
Create a light emitting layer of 00 angstrom and place a mug on it.
1500 on with an alloy of 10: 1 mixture of nesium and silver
An electrode having a thickness of Gstrom is formed to form the organic layer shown in FIG.
An EL device was obtained. This element has a DC voltage of 10 V
Light emission of cd / m ² was obtained.

From the results of Example 6 and Comparative Example 2 , it is understood that the emission brightness can be significantly improved by doping the light emitting layer with the compound of the present invention as a light emission assisting material for other known light emitting substances. It was Furthermore, 1 mA / c
After continuous light emission at m ² , it was found that the light emission time was improved by 5 times or more.

Example 7 N, N'-diphenyl-N, N '-(3-methylphenyl) -1,1'-on a washed glass plate with ITO electrodes
Biphenyl-4,4'-diamine was vacuum-deposited to obtain a hole injection layer having a film thickness of 300 Å. Then
A light emitting layer having a film thickness of 200 Å of the compound ( 25 ) was formed by a vacuum evaporation method, and further, [2- (4-tert-butylphenyl) -5- (biphenyl) -1,3,4-oxa was formed by a vacuum evaporation method. Diazole] film thickness 20
A 0 angstrom electron injection layer was obtained. On top of that, an alloy of magnesium and silver mixed at a ratio of 10: 1 has a thickness of 150.
An organic E shown in FIG. 3 is formed by forming a 0 angstrom electrode.
An L element was obtained. This device, about the DC voltage 10V 290
Light emission of cd / m ² was obtained. Comparative Example 3 Instead of the compound of Compound (25), the following compound (2
Organic EL was prepared in the same manner as in Example 7 except that 7) was used.
A device was produced. This element is 140V at a DC voltage of 10V.
Although a light emission luminance of cd / m ² was obtained, it was continuous at 1 mA / cm ² .
When light was emitted continuously, the brightness was reduced to half in about 400 hours.

When all the organic EL devices shown in this embodiment were made to emit light continuously at 1 mA / cm ² , 10
Stable light emission could be observed for 00 hours or more. The organic EL device of the present invention achieves improvement in luminous efficiency, luminous brightness, and long life.
Luminescent auxiliary material, hole transport material, electron transport material, sensitizer,
The resin, the electrode material and the like and the method for manufacturing the element are not limited.

[0041]

According to the present invention, it is possible to obtain an organic EL device having higher luminous efficiency, higher luminance and longer life than ever before.

[0042]

[Brief description of drawings]

FIG. 1 is a sectional view showing a schematic structure of an organic EL element used in Examples 1, 2, and 3.

FIG. 2 is a sectional view showing a schematic structure of an organic EL element used in Examples 4, 5, and 6 and Comparative Example 1.

FIG. 3 is a sectional view showing a schematic structure of an organic EL device used in Example 7.

[Explanation of symbols]

1. substrate 2. Electrode A 3. Hole injection layer 4. Light emitting layer 5. Electron injection layer 6. Electrode B

Continuation of the front page (56) Reference JP-A-5-70773 (JP, A) JP-A-3-177486 (JP, A) JP-A-3-255190 (JP, A) JP-A-61-62584 (JP , A) JP 61-37884 (JP, A) JP 4-28197 (JP, A) JP 4-237993 (JP, A) JP 4-230997 (JP, A) JP 5-302081 (JP, A) JP-A-6-206865 (JP, A) JP-A-2-311591 (JP, A) JP-A-6-220441 (JP, A) JP-A-6-220440 (JP, A) A) JP-A-6-184532 (JP, A) JP-A-6-271846 (JP, A) JP-A-63-244042 (JP, A) JP-A-2-136860 (JP, A) (58) Survey Areas (Int.Cl. ⁷ , DB name) C09K 11/06 H05B 33/14 H05B 33/22 G03G 5/06 CA (STN) REGISTRY (STN)

Claims (2)

(57) [Claims] 1. An organic elect represented by the following general formula [2]:
Luminescent material for luminescent elements . General formula [2] [Wherein A ² is O, S, Se, Te, NR ²⁵ , P
R ²⁶ , SO ₂ , CH ₂ , CH = CH, C = C (CN) ₂ ,
C = X, CR ²⁸ R ²⁹ , B ² is O, S, Se, T
e, NR ²⁵ , PR ²⁶ , CH ₂ , CH = CH, CR ²⁸ R ²⁹
Indicates. Further, A ² or B ² may be directly bonded without interposing A ² or B ² . Where R
⁹ to R ²⁹ are each independently a hydrogen atom, a halogen atom, a cyano group, a nitro group, an amino group, an ester group, a mono- or di-substituted amino group, an acylamino group, a hydroxyl group, an alkoxy group, a mercapto group, an alkyloxy group, Alkylthio group, aryloxy group, arylthio group, siloxy group, acyl group, cycloalkyl group, carbamoyl group,
Carboxylic acid group, sulfonic acid group, substituted or unsubstituted aliphatic group, substituted or unsubstituted aliphatic ring group, substituted or unsubstituted carbocyclic aromatic ring group, substituted or unsubstituted heterocyclic aromatic group It represents a group cyclic group or a substituted or unsubstituted heterocyclic group. X represents O, S, Se or Te. ] 2. In an organic electroluminescence device having a light emitting layer composed of one or more organic compound thin films between a pair of electrodes, the light emitting material contained in the light emitting layer is
The organic electroluminescent element according to claim 1, which is the light emitting material according to claim 1.