JP3082284B2 - Organic electroluminescent 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 electroluminescent device, and more particularly, to a thin film which emits light by applying an electric field by a combination of a hole injection transport layer and an electron injection transport layer made of an organic compound. It concerns a type device.

[0002]

2. Description of the Related Art Conventionally, as a thin film type electroluminescent device,
ZnS, C which are II-VI compound semiconductors of inorganic materials
In general, aS, SrS, and the like are doped with Mn or a rare earth element (Eu, Ce, Tb, Sm, or the like) that is a light emission center. Required (50-1000Hz)
There are problems that the driving voltage is high (up to 200 V), it is difficult to achieve full color (particularly, blue is a problem), and the cost of the peripheral driving circuit is high.

On the other hand, in recent years, electroluminescent devices using organic materials have been developed to improve the above problems. As organic luminescent layer materials, besides anthracene and pyrene which have been known for a long time, cyanine dyes (J. Chem. Soc., Chem. Commu)
n. , P. 557, 1985), pyrazoline (Mol.
Crys. Liq. Cryst. , 135, 355
1986), perylene (Jpn. J. Appl.
Phys. , 25, L773, 1986), or coumarin compounds and tetraphenylbutadiene (JP-A-57-51781).
Furthermore, in order to improve the efficiency of injecting carriers from the electrodes in order to enhance the luminous efficiency, the type of the electrodes is optimized, and a device for providing a hole injection / transport layer and a luminescent layer composed of an organic phosphor is disclosed (Japanese Patent Application Laid-Open No. Sho 57-57). No. 51781, JP-A-59-194.
393, JP-A-63-29569, Ap
pl. Phys. Lett. , 51, 913, 19
1987).

Further, for the purpose of improving the luminous efficiency of the device and changing the luminescent color, a fluorescent dye for laser such as coumarin is doped using an aluminum complex of 8-hydroxyquinoline as a host material (J. Appl. Phys.
s. 65, 3610, 1989).

Also, it has been shown that a naphthalimide derivative (N1) having the following structural formula is used as a material for an organic electron injection / transport layer also serving as a light emitting layer (Appl. Ph.
ys. Lett. 56, 799, 1990), such devices exhibit only 35 cd / m ² brightness when driven at a current density of 100 mA / cm ² .

[0006]

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Further, naphthalimide derivatives and N-butylnaphthalimide of the following structural formula (N2) have been shown to be used as a host material to be doped with a fluorescent dye (Technical Research Report of the Institute of Electronics and Communication Engineers, OME89). -46, 19
1989, JP-A-3-26780), and only a low value of 100 to 200 cd / m ² is obtained as the emission luminance.

[0008]

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[0009]

As described above, in the organic electroluminescent devices disclosed so far, the luminous performance,
In particular, the luminous efficiency is still insufficient, and further improvement studies have been desired.

The present invention has been made in view of the above-mentioned conventional situation, and has as its object to provide an organic electroluminescent device that can be driven with high luminous efficiency.

[0011]

The organic electroluminescent device of the present invention According to an aspect of the sequentially, an anode, an organic hole injecting and transporting layer which does not contain a basic polymer, an organic electron injecting and transporting layer and a cathode which does not contain a basic polymer In a stacked organic electroluminescent device, an organic hole injection / transport compound in an organic hole injection / transport layer and / or an organic electron injection / transport in an organic electron injection / transport layer .
Using the compound as a host material, the host material is doped with a naphthalimide derivative represented by the following general formula (I).
It has been characterized by Rukoto.

[0012]

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In the above formula (I), R ¹ is a hydrogen atom,
Alkyl group, aralkyl group, alkenyl group, allyl group,
An aromatic hydrocarbon ring group or an aromatic heterocyclic group which may have a substituent, X represents an oxygen atom or a sulfur atom, R ² and R ³
Is a hydrogen atom, a halogen atom, a nitro group, an amino group which may have a substituent, a cyano group, an alkoxy group, an alkylcarbonyl group, an alkoxycarbonyl group, an alkyl group, an alkenyl group, an allyl group, X ¹ and X ² Represents a hydrogen atom, a halogen atom, a nitro group, a cyano group, an alkoxy group, or an alkoxycarbonyl group. In the present invention,
The doping amount of the naphthalimide derivative depends on the host material.
Is preferably 10 ⁻³ to 10 mol%.

That is, the present inventors have made intensive studies on an organic electroluminescent device which can be driven with high luminous efficiency. As a result, the organic hole injecting and transporting layer and / or the organic electron injecting and transporting layer have a specific compound. The present inventors have found that it is preferable to contain them, and have completed the present invention.

Hereinafter, the organic electroluminescent device of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a sectional view schematically showing an example of the structure of an organic electroluminescent device according to the present invention, wherein 1 is a substrate, 2a, 2b
Represents a conductive layer, 3 represents an organic hole injecting and transporting layer, and 4 represents an organic electron injecting and transporting layer.

The substrate 1 serves as a support for the organic electroluminescent device of the present invention. Usually, a quartz or glass plate, a metal plate or a metal foil, a plastic film or a sheet, or the like is used. A glass plate or a transparent synthetic resin substrate such as polyester, polymethyl methacrylate, polycarbonate, and polysulfone is preferable.

The conductive layer 2a is provided on the substrate 1. The conductive layer 2a is usually made of a metal such as aluminum, gold, silver, nickel, palladium, and tellurium, a metal oxide such as an oxide of indium and / or tin, copper iodide, carbon black, or poly (3- (Methylthiophene) and the like.

In the example shown in FIG. 1, the conductive layer 2a functions as an anode (anode) to inject holes. On the other hand, the conductive layer 2b plays a role of injecting electrons into the organic electron injection / transport layer 4 as a cathode (cathode). As the constituent material of the conductive layer 2b, the constituent material of the conductive layer 2a can be used. However, for efficient electron injection, a metal having a low work function is preferable.
Suitable metals such as magnesium, indium, aluminum, silver and the like or alloys thereof are preferred.

The conductive layers 2a and 2b are usually formed by a sputtering method, a vacuum deposition method or the like in many cases. However, fine metal particles such as silver or copper iodide, carbon black, conductive metal oxide fine particles, In the case of a conductive resin fine powder or the like, these powders can also be formed by dispersing these powders in an appropriate binder resin solution and applying the powder on a substrate. Further, in the case of a conductive resin, a thin film can be formed directly on a substrate by electric field polymerization. Note that the conductive layers 2a and 2b may be composite layers formed by laminating two or more substances.

The thickness of the conductive layer 2a depends on the required transparency. If transparency is required, it is desirable that the visible light transmittance is 60% or more, preferably 80% or more. In this case, the thickness is usually 50 to 10,
000 °, preferably about 100 to 5,000 °. When the conductive layer 2a may be opaque, the conductive layer 2a
The material of a may be the same as that of the substrate 1, and furthermore, the conductive layer may be laminated with another material different from the conductive layer constituting material. On the other hand, the thickness of the conductive layer 2b is generally equal to the thickness of the conductive layer 2a.

Although not shown in FIG. 1, this conductive layer 2
A substrate similar to the substrate 1 can be further provided on b. However, at least one of the conductive layers 2a and 2b needs to have good transparency as an electroluminescent element. From this, at least one of the conductive layers 2a and 2b
The thickness is preferably 5,000 to 5,000, and good transparency is desired.

The organic hole injecting and transporting layer 3 provided on the conductive layer 2a can efficiently transport holes from the anode toward the organic electron injecting and transporting layer 4 between the electrodes to which an electric field is applied. It needs to be formed from a compound that can. Therefore, the organic hole injection / transport compound needs to be a compound having a high hole injection efficiency from the conductive layer 2a and capable of efficiently transporting the injected holes. For this purpose, the ionization potential is small, the hole mobility is large, and the stability is excellent.
It is required that impurities serving as traps are compounds that hardly occur during production or use.

Examples of such hole injecting and transporting compounds include those described in JP-A-59-194393, pp. 5-6 and US Pat. No. 4,175,960, columns 13-14. . Preferred specific examples of these compounds include N, N'-diphenyl-N, N '-(3
-Methylphenyl) -1,1'-biphenyl-4,4 '
-Diamine: 1,1'-bis (4-di-p-tolylaminophenyl) cyclohexane: aromatic amine compounds such as 4,4'-bis (diphenylamino) quadrophenyl. In addition to the aromatic amine compounds, hydrazone compounds described in JP-A-2-311591 can be mentioned. These aromatic amine compounds or hydrazone compounds are used alone or, if necessary,
Each of them may be used as a mixture.

The organic electron injecting and transporting layer 4 provided on the organic hole injecting and transporting layer 3 efficiently transports electrons from the cathode toward the organic hole injecting and transporting layer between the electrodes to which an electric field is applied. It is required to be formed from a compound that can. Therefore, the organic electron injecting and transporting compound needs to be a compound having high electron injecting efficiency from the conductive layer 2b and capable of efficiently transporting the injected electrons. For this purpose, it is required that the compound has high electron affinity, high electron mobility, excellent stability, and hardly generates impurities serving as traps during production or use.

Materials satisfying such conditions include aromatic compounds such as tetraphenylbutadiene (Japanese Unexamined Patent Publication No.
And metal complexes such as aluminum complexes of 8-hydroxyquinoline (JP-A-59-1943).
No. 93), cyclopentadiene derivatives (Japanese Unexamined Patent Publication No.
289675), perinone derivatives (JP-A 2-2)
No. 89676), oxadiazole derivatives (Japanese Patent Application Laid-Open No. 2-216991), and bisstyrylbenzene derivatives (Japanese Patent Application Laid-Open Nos. 1-245087 and 2-222448).
No. 4), perylene derivatives (JP-A-2-189890)
JP-A-3-7991), coumarin compounds (JP-A-2-191694 and JP-A-3-792), rare-earth complexes (JP-A-1-256584), and distyrylpyrazine derivatives (JP-A-2-19584). 252793). When these compounds are used, the organic electron injecting and transporting layer simultaneously plays a role of transporting electrons and a role of emitting light when holes and electrons recombine.

In the organic electroluminescent device of the present invention, the organic hole injecting and transporting layer and / or the organic electron injecting and transporting layer made of such a material contains the naphthalimide derivative represented by the above general formula (I). However, in the normal case, the organic electron injecting and transporting layer 4 is doped with the naphthalimide derivative represented by the general formula (I). The region to be doped may be the whole or part of the organic electron injecting and transporting layer 4, and as shown in FIG. It may be a layer 4a near the interface (in FIG. 2, 4b is an undoped region, and numerals 1, 2a, 2b, 3 indicate the same as in FIG. 1). The amount of the naphthalimide derivative to be doped into the host material is 10 ⁻³ to 1.
0 mol% is preferred. In addition, the host material is, for example,
The organic electron injecting When transporting layer 4 is its role, an organic electron injecting and transporting compound described above, the organic hole injection transport layer 3
If is serves its, an organic hole injecting and transporting compound such as an aromatic amine compound or a hydrazone compound as described above.

In the general formula (I), R ¹ is preferably a hydrogen atom; an alkyl group having 1 to 6 carbon atoms such as a methyl group and an ethyl group; an alkoxyalkyl group such as a methoxyethyl group and an ethoxyethyl group; Alkoxyalkoxyalkyl groups such as methoxy-ethoxyethyl group and n-butoxyethoxyethyl group; alkoxyalkoxyalkoxyalkyl groups such as methoxyethoxyethoxyethyl group and ethoxyethoxyethoxyethyl group; phenyloxyethyl group, naphthyloxyethyl group, p- Aryloxyalkyl groups such as chlorophenyloxyethyl group; arylalkyl groups such as benzyl group, phenethyl group, p-chlorobenzyl group and p-nitrobenzyl group; cycloalkyl groups such as cyclohexylmethyl group, cyclohexylethyl group and cyclopentylethyl group Alkylalkyl group; alkenyloxyalkyl group such as allyloxyethyl group and 3-bromoallyloxyethyl group; cyanoalkyl group such as cyanoethyl group and cyanomethyl group; hydroxyalkyl group such as hydroxyethyl group and hydroxymethyl group; tetrahydrofuryl group A substituted or unsubstituted alkyl group such as a tetrahydrofurylalkyl group such as a tetrahydrofurylethyl group,
Allyl group, substituted or unsubstituted alkenyl group such as 2-chloroallyl group, phenyl group, p-methylphenyl group, naphthyl group, substituted or unsubstituted aryl group such as m-methoxyphenyl group, cyclohexyl group, cyclobentyl group, etc. And cycloalkyl groups.

R ² and R ³ are a hydrogen atom; a halogen atom; a nitro group; an amino group which may have a substituent such as an alkyl group or an aryl group; a cyano group; a carbon number such as a methoxy group or an ethoxy group. An alkoxycarbonyl group having 1 to 6 carbon atoms such as a methoxycarbonyl group and an ethoxycarbonyl group; an alkylcarbonyl group such as a methylcarbonyl group and an ethylcarbonyl group; a methyl group and an ethyl group; An alkyl group having 1 to 6 carbon atoms; an arylalkyl group such as a benzyl group, a phenethyl group, a p-chlorobenzyl group, and a p-nitrobenzyl group; a cycloalkylalkyl group such as a cyclohexylmethyl group, a cyclohexylethyl group, and a cyclopentylethyl group; Alkenyloxy such as allyloxyethyl group and 3-bromoallyloxyethyl group Alkyl group; hydroxyl group; substituted or unsubstituted alkenyl group such as 2-chloroallyl group, substituted or unsubstituted aryl group such as phenyl group, p-methylphenyl group, naphthyl group, m-methoxyphenyl group, cyclohexyl group, cyclobentyl group And the like.

X ¹ and X ² include a hydrogen atom, a halogen atom, an alkoxy group, an amino group and a nitro group, and preferably a hydrogen atom or a nitro group.

The method for synthesizing these naphthalimide derivatives is described, for example, in Japanese Patent Publication No.
No. 7-8465, JP-B-53-5304 and the like. Specifically, the following general formula (II) ((I
I) In the formula, R ² , R ³ , X ¹ and X ² have the same meaning as in the general formula (I). )) And a compound represented by the general formula R ¹ NH ₂ (wherein R ¹ has the same meaning as in the general formula (I)) in a suitable solvent. It is synthesized by reacting with

[0032]

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Specific examples of the naphthalimide derivative represented by the general formula (I) thus obtained are shown in the following structural formulas (1) to (10), but are not limited thereto.

[0034]

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In the present invention, the organic hole injection transport layer 3
Is formed, for example, by laminating on the conductive layer 2a by a coating method or a vacuum evaporation method. In the case of coating, a coating solution prepared by adding and dissolving one or more organic hole injecting / transporting compounds and, if necessary, a binder resin which does not trap holes, or an additive such as a coating property improving agent such as a leveling agent. Is prepared, applied to the conductive layer 2a by a method such as spin coating, and dried to form the organic hole injection / transport layer 3. Examples of the binder resin include polycarbonate, polyarylate, and polyester.
If the amount of the binder resin is large, the hole mobility is reduced. Therefore, it is desirable that the amount of the binder resin is small, and it is preferably 50% by weight or less based on the coating solution.

In the case of the vacuum evaporation method, the organic hole injecting / transporting material is put in a crucible provided in a vacuum vessel, and the inside of the vacuum vessel is evacuated to 10 ^-6 Torr by a suitable vacuum pump. Heating to evaporate the hole injection transport material,
A layer is formed on a substrate placed opposite the crucible.

The thickness of the organic hole injection / transport layer 3 is usually 1
It is 00 to 3000 °, preferably 300 to 1000 °. In order to uniformly form such a thin film, a vacuum deposition method is preferable.

On the other hand, the organic electron injecting and transporting layer 4 doped with the naphthalimide derivative represented by the general formula (I)
Is formed on the organic hole injecting and transporting layer 3 by, for example, a coating method or a vacuum evaporation method.

In the case of coating, an organic electron injecting / transporting compound, a naphthalic imide derivative represented by the above general formula (I), and, if necessary, a binder resin which does not act as an electron trap or a quencher of light emission, a leveling agent Add additives such as coatability improver, etc., prepare a dissolved coating solution,
Organic hole injection transport layer 3 by a method such as spin coating
The organic electron injecting and transporting layer 4 is formed by coating and drying. Examples of the binder resin include polycarbonate, polyarylate, and polyester. If the amount of the binder resin is large, the electron mobility is reduced. Therefore, the amount of the binder resin is preferably small, and is preferably 50% by weight or less based on the coating solution.

In the case of the vacuum deposition method, the organic electron injecting and transporting material is put in a crucible placed in a vacuum vessel, and the naphthalimide derivative represented by the general formula (I) is put in another crucible, The inside of the container is 10 ^-6 To with a suitable vacuum pump.
After evacuating to about rr, each crucible is heated simultaneously to evaporate the contents and form a layer on the organic hole injecting and transporting layer 3 of the substrate 1 placed facing the crucible. Also,
As another method, a mixture of the above materials at a predetermined ratio may be evaporated using the same crucible. The thickness of the organic electron injecting and transporting layer 4 is usually 100 to 2000 °, preferably 300 to 1000 °. In order to form such a thin film uniformly, a vacuum evaporation method is preferably used in a normal case.

In order to further improve the luminous efficiency of the organic electroluminescent device, another organic electron injecting layer is formed on the organic electron injecting and transporting layer 4 doped as described above, as shown in FIG. Laminating the transport layer 5 is conceivable. The compound used for the organic electron injecting and transporting layer 5 is required to be capable of easily injecting electrons from the cathode and having a higher electron transporting ability. Such organic electron injecting and transporting materials include nitro-substituted fluorenone derivatives such as the compound shown in Chemical formula 7, thiopyran dioxide derivatives such as the compound shown in Chemical formula 8, diphenylquinone derivatives such as the compound shown in Chemical formula 9, and Perylenetetracarboxylic acid derivatives such as the compounds shown (Jpn. J. Appl. Phys. 27
Oxadiazole derivative (Appl. Phys. L
ett. 55, 1489, 1989).

[0042]

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[0043]

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[0044]

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[0045]

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[0046]

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The thickness of the organic electron injecting and transporting layer 5 is usually 100 to 2000 °, preferably 300 to 1１.
000.

In the present invention, a structure opposite to that shown in FIG. 1, that is, a structure in which a conductive layer 2b, an organic electron injection / transport layer 4, an organic hole injection / transport layer 3, and a conductive layer 2a are laminated on a substrate in this order. It is also possible to employ the organic electroluminescent element of the present invention between two substrates, at least one of which has high transparency, as described above. Similarly, FIGS. 2 and 3 can also be stacked in a structure opposite to these.

[0049]

The use of the naphthalimide derivative represented by the general formula (I) as a doping material for the organic hole injecting / transporting layer and / or the organic electron injecting / transporting layer of the organic electroluminescent device is excellent. It is possible to provide luminescent properties.

By the way, for the purpose of improving the luminous efficiency of the organic electroluminescent device and changing the luminescent color, various fluorescent dyes are doped with an aluminum complex of 8-hydroxyquinoline as a host material ( U.S. Pat. No. 4,769,292). The advantage of this method is that the luminous efficiency is improved by the highly efficient fluorescent dye,
The emission wavelength can be varied by selecting the fluorescent dye, a fluorescent dye that causes concentration quenching can be used, and a fluorescent dye with poor thin film properties can be used.

On the other hand, a solution obtained by dissolving the naphthalic imide derivative represented by the above formula (6) in acetone at a concentration of 3 × 10 ^-3 mol / liter is supplied to a mercury lamp (wavelength: 35
0 nm).
It is as follows. The standard of the relative fluorescence intensity was a chloroform solution of aluminum 8-hydroxyquinoline complex (Al (OX) ₃ , abbreviated in the table). From these results, the effect of improving the light emission characteristics according to the present invention is apparent.

[0052]

[Table 1]

[0053]

Next, the present invention will be described more specifically with reference to examples and comparative examples, but the present invention is not limited to the description of the following examples unless it exceeds the gist. Examples 1 and 2 An organic electroluminescent device having the structure shown in FIG. 1 was produced by the following method. Indium tin oxide (IT
O) A transparent conductive film deposited to a thickness of 1200 mm is washed with water and further ultrasonically washed with isopropyl alcohol.
Installed in a vacuum evaporation system, the degree of vacuum in the system is 2 × 10
Air was exhausted using an oil diffusion pump until the pressure became ^-6 Torr or less. The following hydrazone compounds (H1) and (H2) are used as organic hole injection / transport layer materials in a molar ratio of (H1):
The mixture mixed at (H2) = 1: 0.3 was placed in a ceramic crucible, heated by a tantalum wire heater around the crucible, and evaporated in a vacuum vessel. Crucible temperature is 150 ~
In the range of 190 ° C., the degree of vacuum at the time of vapor deposition is 6 × 10 ⁻⁷ Torr.
r. The organic hole injecting and transporting layer is
It was deposited with a thickness of 0 °. The deposition time was 4 minutes.

[0054]

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Next, as a material for the organic electron injection / transport layer,
An 8-hydroxyquinoline complex of aluminum represented by the following structural formula, Al (C ₉ H ₆ NO) _3, is used as a fluorescent dye to be doped with a naphthalimide derivative represented by the formula ( ₆ ).
Each was heated and vapor-deposited at the same time using separate crucibles.

[0056]

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At this time, the temperature of each crucible was 200 to 2 with respect to the 8-hydroxyquinoline complex of aluminum.
30 ° C., 125-125 for naphthalimide derivatives
Controlled at 140 ° C. The degree of vacuum during evaporation is 7 × 10 ^-7 To
At rr, the deposition time was 2 minutes. As a result, the film thickness 5
At 10 °, an organic electron injecting and transporting layer was obtained in which the naphthalimide derivative was doped with 2.2 mol% of the above complex.

Finally, as a cathode, an alloy electrode of magnesium and silver was formed by vapor deposition at a thickness of 1500 ° by a binary simultaneous vapor deposition method. The deposition was performed using a molybdenum boat, the degree of vacuum was set to 8 × 10 ⁻⁶ Torr, and the deposition time was set to 8 minutes. As a result, a glossy film was obtained. The atomic ratio of magnesium to silver was in the range of 10: 1 to 2. Thus, an organic electroluminescent device A was produced.

A positive electrode was added to the ITO electrode (anode) and a magnesium / silver electrode (cathode) of the organic electroluminescent device A.
Table 2 shows the results of the light emission characteristics measured by applying a negative DC voltage to. The peak wavelength of the emission spectrum of this device was 510 nm, and uniform green light emission was exhibited.

In Table 2, Vth indicates a luminance of 1c.
The voltage and the luminous efficiency at d / m ² are the efficiencies at V ₁₀₀ .

Comparative Example 1 An organic electroluminescent device B was produced in the same manner as in Example 1, except that the organic electron injecting and transporting layer was not doped with a naphthalic imide derivative. Table 2 shows the measurement results of the light emission characteristics of this device. The peak wavelength of the emission spectrum of this device is 5
At 30 nm, a green uniform light emission was exhibited.

Comparative Example 2 An organic electron injecting and transporting layer was formed in the same manner as in Example 1 except that an aluminum complex of 8-hydroxyquinoline was not used as the host material of the organic electron injecting and transporting layer, and the organic electron injecting and transporting layer was formed only with a naphthalic imide derivative. Element C was produced. Table 2 shows the measurement results of the light emission characteristics of this device. This device emitted yellow light.

[0063]

[Table 2]

[0064]

As described above in detail, according to the organic electroluminescent device of the present invention, an anode, an organic hole injecting and transporting layer, an organic electron injecting and transporting layer, and a cathode are sequentially provided on a substrate. Since the specific hole-transporting layer and / or the organic electron-injecting and transporting layer, or a part thereof, is doped with a specific naphthalic acid imide derivative, when a voltage is applied to both electrodes, light emission with practically sufficient luminance at a low driving voltage is obtained. Thus, the initial light emission characteristics can be maintained even after long-term storage. The electroluminescent element of the present invention is a light source (for example, a light source of a copying machine, a backlight light source of a liquid crystal display or an instrument), a display plate utilizing the characteristics of the field of a flat panel display (for example, a wall-mounted television) or an image luminous body. It can be applied to sign lights, and its industrial utility is extremely large.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the organic electroluminescent device of the present invention.

FIG. 2 is a sectional view showing another embodiment of the organic electroluminescent device of the present invention.

FIG. 3 is a sectional view showing another embodiment of the organic electroluminescent device of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Substrate 2a, 2b Conductive layer 3 Organic hole injection transport layer 4 Organic electron injection transport layer

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C09K 11/06 CA (STN) REGISTRY (STN)

Claims (2)

(57) [Claims] Claims 1. An anode and a basic polymer are not included in order.
There organic hole injection transport layer, the organic electroluminescent device wherein an organic electron injection transport layer and a cathode does not contain a basic polymer are laminated, the organic hole injection organic hole injection transport layer exports
Organic electronic note feed compounds and / or organic electron injecting and transporting layer
The transport compound is used as a host material ,
Naphthalimide derivative represented by the following general formula (I)
The organic electroluminescent device but characterized that you have been doped. Embedded image (Wherein R ¹ is a hydrogen atom, an alkyl group, an aralkyl group,
An alkenyl group, an allyl group, an aromatic hydrocarbon ring group or an aromatic heterocyclic group which may have a substituent, R ² and R ^{3 each} have a hydrogen atom, a halogen atom, a nitro group, a substituent; Amino group, cyano group, alkoxy group, alkylcarbonyl group, alkoxycarbonyl group, alkyl group,
An alkenyl group, an allyl group, X ¹ and X ² represent a hydrogen atom, a halogen atom, a nitro group, a cyano group, an alkoxy group, or an alkoxycarbonyl group. ) (2) 2. The naphthalimide according to claim 1,
When the doping amount of the derivative is 10 ^-3 ~ 1
An organic electroluminescent device, which is 0 mol%.