JP2000191560A - Aromatic hydrocarbon compound and organic electroluminescence element using thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a new aromatic hydrocarbon compound having an anthracene structure useful as a constituting material for an organic electroluminescence element exhibiting high heat resistance and having excellent luminous efficacy. SOLUTION: Compounds of formulae I, II and III Ar1 to Ar5 are each a (substituted) hydrocarbon group having the number of nuclear atoms of 5-40; m=1-3; p=3-8; q=0-2, and r=0-4, and at the same time q+r=3-8; X is a group of formula IV [R1 and R2 are each a (substituted) hydrocarbon group having the number of nuclear atoms of 5-40]}. For example, a compound of formula V. Compounds of formulae I to III are obtained for example, by coupling a halide of an aromatic compound with a halide of a styryl compound through a method such as Grignard reaction.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a novel aromatic hydrocarbon compound and an organic electroluminescence device using the compound (hereinafter sometimes referred to as an organic EL device). More specifically, the present invention relates to an aromatic hydrocarbon compound having high utility as a constituent material of an organic EL device, and to an organic EL device using the compound, which is excellent in heat resistance and luminous efficiency.

[0002]

2. Description of the Related Art An organic EL device utilizing electroluminescence has characteristics of high visibility because it is self-luminous, and excellent impact resistance because it is a completely solid device. Therefore, it is used in fields such as thin film display elements, backlights of liquid crystal displays, and flat light sources.

[0003] The electroluminescent element currently put to practical use is a dispersion type electroluminescent element. Since this dispersion type electroluminescence element requires an AC voltage of several tens of volts or 10 kilohertz or more, its driving circuit is complicated. For these reasons, organic EL elements capable of reducing the driving voltage to about 10 volts and emitting light with high luminance have been actively studied in recent years. For example, C.I. W.
Tang and S.M. A. Van Slyke Ap
pl. Phys. Lett. , Vol. 51 pp. 9
13-915 (1987) and JP-A-63-26462.
Japanese Patent Application Laid-Open Publication No. 9-29139 proposes an organic thin film EL device having a laminated type of a transparent electrode / a hole injection layer / a light emitting layer / a back electrode. Holes can be efficiently injected into the light emitting layer. The light emitting layer used in such an organic EL device may be a single layer,
As described above, since the balance between the electron transporting property and the hole transporting property was not good, the performance was improved by laminating in multiple layers.

However, in order to form such a laminated structure, there are problems that the manufacturing process is complicated and the required time is long, and that there are many restrictions such as a requirement for each layer to be thin. Furthermore, in recent years, there has been an increasing demand for downsizing of information devices and the like and a shift to a portable type, and there has been an increasing demand for further lowering these drive voltages. Therefore, development of a light emitting material, a hole transport material, and the like has been attempted in order to reduce the weight and drive voltage. Anthracene is known as a light-emitting material, but since it is difficult to form a uniform thin film, derivatives into which various substituents are introduced have been proposed. For example, Japanese Unexamined Patent Publication (Kokai) No. 7-119407 proposes to use an anthracene having a distearyl skeleton as a light emitting material, but has insufficient heat resistance. Also, JP-A-8-1
Japanese Patent Publication No. 2600 proposes to use a dimer of anthracene as a light emitting material, but has a drawback that the light emitting efficiency is low.

[0005]

SUMMARY OF THE INVENTION In view of the above situation, the present invention provides an aromatic carbon material which exhibits high heat resistance and exhibits excellent luminous efficiency when used as a constituent material of an organic EL device. It is an object of the present invention to provide a hydrogen compound and an organic EL device using the same.

[0006]

Means for Solving the Problems The present inventors have made various studies to solve the above problems, and as a result, have found that an aromatic hydrocarbon compound having a specific chemical structure achieves the above object. Based on these findings, the present invention has been completed. That is, the gist of the present invention is as follows. (1) An aromatic hydrocarbon compound represented by any of the following general formulas [1] to [3].

[0007]

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In the formulas (1) to (3), Ar ^{1 to} Ar ⁵ are a hydrocarbon group having 5 to 40 nucleus atoms which may have a substituent, m is an integer of 1 to 3, p is an integer of 3 to 8, q is an integer of 0 to 2, r is an integer of 0 to 4, and (q + r) is an integer of 3 to 8, X is the following general formula [4],

[0009]

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(In the formula [4], R ¹ and R ² are each independently a hydrocarbon group having 5 to 40 nucleus atoms which may have a substituent.) (2) An organic electroluminescent device having an organic light emitting layer sandwiched between at least a pair of electrodes,
An organic electroluminescence device containing an aromatic hydrocarbon compound represented by any one of the general formulas [1] to [3]. (3) The organic electroluminescent device according to (2), wherein the aromatic hydrocarbon compound represented by any of the general formulas [1] to [3] is mainly contained in a light emission band. (4) The organic electroluminescent device according to (2) or (3), wherein the aromatic hydrocarbon compound represented by any of the general formulas [1] to [3] is contained in a light emitting layer.

[0011]

BEST MODE FOR CARRYING OUT THE INVENTION The aromatic hydrocarbon compound of the present invention is an aromatic hydrocarbon compound represented by any of the above general formulas [1] to [3]. Then, the general formulas [1] to
In the aromatic hydrocarbon compound represented by any of [3], the number of substitution of the group represented by the general formula [4] bonded to the anthracene skeleton or the anthracene skeleton to which the aromatic ring is bonded is important, It is desirable that p in the general formula [1] and (q + r) in the general formula [2] be from 3 to 8, preferably from 3 to 6.

Then, R ¹ and R ² in the general formula [4]
Examples of the hydrocarbon group having 5 to 40 nuclear atoms which may have a substituent represented by phenyl group, phenylene group, naphthyl group, naphthylene group, biphenyl group, biphenylene group, anthranyl group, terphenyl group, terphenyl group Phenylene group, anthranyl group, phenanthryl group, bienyl group,
Examples include a diphenylnaphthyl group, a ciphenylanthracenylene group, a pyrrolyl group, a furanyl group, a thiophenyl group, a pyridyl group, a pyrazyl group, an indolyl group, and a benzothiazolyl group. Among these hydrocarbon groups, phenyl, phenylene, naphthyl, naphthylene, biphenyl, biphenylene, and anthracenylene groups are preferred. Here, the number of nuclear atoms is
It means the total number of atoms that make up a carbocyclic or heterocyclic ring.

The substituents which these hydrocarbon groups may have include an alkyl group having 1 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, an aryloxy group having 5 to 40 nuclear atoms, Examples include an amino group, a nitro group, a cyano group, an ester group having 1 to 6 carbon atoms, and a halogen atom substituted with an aryl group having 5 to 40 nuclei atoms. Examples of the alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a propyl group,
Isopropyl group, butyl group, isobutyl group, sec-butyl group, tert-butyl group, various pentyl groups, various hexyl groups, and the like. Examples of the alkoxy group having 1 to 6 carbon atoms include methoxy group, ethoxy group, and propoxy group. Group, isopropoxy group, butoxy group, isobutoxy group,
Examples include a sec-butoxy group, a tert-butoxy group, various pentyloxy groups, various hexyloxy groups, and the like.

Next, specific examples of the aromatic hydrocarbon compound represented by any of the above general formulas [1] to [3] are as follows.

[0015]

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[0016]

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[0017]

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[In the above formula, Ph is a phenyl group, p-Me
Ph represents a p-methylphenyl group, and p-CNPh represents a P-cyanophenyl group. Then, for a method for producing an aromatic hydrocarbon compound represented by any of the general formulas [1] to [3], for example, a halogenated aromatic compound and a halogenated styryl compound are converted into Grignard. Any compound can be efficiently obtained by coupling by a method such as a reaction.

Next, the organic EL device of the present invention is constituted by sandwiching an organic light-emitting layer between a pair of electrodes, and the device preferably has the above-mentioned aromatic hydrocarbon in its light-emitting band, especially in the organic light-emitting layer. It is configured to contain a compound. A typical device configuration of this organic EL device is as shown below, but is not limited thereto. Anode / light-emitting layer / cathode anode / hole-injection layer / light-emitting layer / cathode anode / light-emitting layer / electron injection layer / cathode anode / hole-injection layer / light-emitting layer / electron injection layer / cathode anode / organic semiconductor layer / light-emitting layer / Cathode anode / organic semiconductor layer / electron barrier layer / emission layer / cathode anode / organic semiconductor layer / emission layer / adhesion improving layer / cathode anode / hole injection layer / hole transport layer / emission layer / electron injection layer / cathode Among these various element configurations, those having the above configuration are preferably used. As the aromatic hydrocarbon compounds represented by the general formulas [1] to [3], those mainly contained in the light-emitting band, particularly the light-emitting layer, of these components are preferably used. The content of the aromatic hydrocarbon compound in the light emitting layer is preferably 30 to 100% by weight based on the entire light emitting layer.

The organic EL device is manufactured on a light-transmitting substrate. This light-transmitting substrate is a substrate that supports the organic EL element.
It is desirable that the transmittance of light in a visible region of 0 nm is 50% or more, and it is more preferable to use a smooth substrate. As such a translucent substrate, for example, a glass plate, a synthetic resin plate, or the like is suitably used. Examples of the glass plate include a plate formed of soda lime glass, barium / strontium-containing glass, lead glass, aluminosilicate glass, borosilicate glass, barium borosilicate glass, quartz, or the like. Examples of the synthetic resin plate include plates made of polycarbonate resin, acrylic resin, polyethylene terephthalate resin, polyether sulfide resin, polysulfone resin, and the like.

Next, as the above-mentioned anode, those using a metal, an alloy, an electrically conductive compound or a mixture thereof having a large work function (4 eV or more) as an electrode material are preferably used. A specific example of such an electrode material is Au.
And conductive materials such as CuI, ITO, SnO2, and ZnO. In order to form this anode, a thin film can be formed from these electrode substances by a method such as an evaporation method or a sputtering method. The anode desirably has such a property that, when light emitted from the light emitting layer is extracted from the anode, the transmittance of the anode to the emitted light is greater than 10%. The sheet resistance of the anode is several hundred Ω.
/ □ or less is preferred. Further, the thickness of the anode is selected in the range of usually 10 nm to 1 μm, preferably 10 to 200 nm, although it depends on the material.

The light emitting layer of the organic EL device of the present invention preferably has the following functions. Injection function; Function that can inject holes from the anode or hole injection layer when applying an electric field, and can inject electrons from the cathode or electron injection layer. Transport function: Transfers the injected charges (electrons and holes) to the electric field. The function of moving with the force of light Emission function; The function of providing a recombination field of electrons and holes and connecting it to light emission However, there is a difference between the ease of hole injection and the ease of electron injection. Although the transport ability represented by the mobility of holes and electrons may be large or small, it is preferable to transfer one of the charges.

The aromatic hydrocarbon compound having an anthracene skeleton represented by the general formulas [1] to [3] of the present invention satisfies the above three conditions, and is mainly used for forming a light emitting layer. However, when this aromatic hydrocarbon compound is used for a layer other than the light emitting layer, the following light emitting materials can be used. The light emitting material of the organic EL device is mainly an organic compound, and specifically, the following compounds are used depending on a desired color tone.

For example, when obtaining violet light emission from the ultraviolet region, a compound represented by the following general formula [5] is preferably used.

[0025]

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[In the above formula, X is the following general formula [6]

[0027]

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(Wherein, n represents an integer of 2 to 5), and Y represents the following general formula [7]

[0029]

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The group represented by The phenyl group, phenylene group, and naphthyl group in the compound represented by the general formula [5] include an alkyl group having 1 to 4 carbon atoms,
4, a compound having one or more substituents such as an alkoxy group, a hydroxyl group, a sulfonyl group, a carbonyl group, an amino group, a dimethylamino group or a diphenylamino group may be used. When there are a plurality of these substituents, they may be bonded to each other to form a saturated 5- or 6-membered ring. Further, as for the form of this compound, a compound bonded to a phenyl group, a phenylene group, or a naphthyl group at a para position is preferable because it has good binding properties and a smooth deposited film is easily formed. Specific examples of the compound represented by the general formula [5] are as follows.

[0031]

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[0032]

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Of these compounds, p-quarterphenyl derivatives and p-quinkphenyl derivatives are particularly preferred. Further, in order to obtain blue to green light emission, for example, a benzothiazole-based, benzimidazole-based, benzoxazole-based fluorescent whitening agent, a metal chelated oxinoid compound, and a styrylbenzene-based compound can be used. Specific examples of these compounds include, for example, compounds disclosed in JP-A-59-194393. Still other useful compounds are described in Chemistry of Synthetic Soy (1971)
Listed on pages 628-637 and 640.

As the chelated oxinoid compound, for example, the compounds disclosed in JP-A-63-295695 can be used. Typical examples include tris (8-quinolinol) aluminum and the like.
-Hydroxyquinoline-based metal complexes, dilithium epintridione and the like can be mentioned as suitable compounds.

Further, as the styrylbenzene-based compound, for example, those disclosed in European Patent Nos. 0319881 and 03753582 can be used. And Japanese Patent Laid-Open No. 25279/1990.
The distyrylpyrazine derivative disclosed in Japanese Patent Publication No. 3 can also be used as a material for the light emitting layer. In addition, polyphenyl compounds disclosed in European Patent No. 0377715 can also be used as a material for the light emitting layer.

Further, in addition to the above-described fluorescent whitening agents, metal chelated oxinoid compounds and styrylbenzene compounds, for example, 12-phthaloperinone (J. App.
l. Phys., Vol. 27, L713 (1988)),
1,4-diphenyl-1,3-butadiene, 1,1,
4,4-tetraphenyl-1,3-butadiene (above A
pp. Phys. Lett., Vol. 56, L799 (1
990)), a naphthalimide derivative (JP-A-2-30)
No. 5886), perylene derivatives (JP-A-2-189)
890), oxadiazole derivatives (Japanese Unexamined Patent Publication No.
No. 2,167,791 or an oxadiazole derivative disclosed by Hamada et al. At the 38th Joint Lecture on Applied Physics, an aldazine derivative (Japanese Unexamined Patent Publication No. 2-220393).
), Pyrazirine derivatives (JP-A-2-220394)
), Cyclopentadiene derivatives (JP-A-2-28)
9675), pyrrolopyrrole derivatives (Japanese Unexamined Patent Publication No.
No. 296891), styrylamine derivatives (App
l. Phys. Lett., Vol. 56, L799 (199)
0), coumarin-based compounds (JP-A-2-191694), International Patent Publication WO90 / 13148 and App.
l. Phys. Lett., vol 58, 18, P198.
2 (1991) can also be used as a material for the light emitting layer.

In the present invention, an aromatic dimethylidin compound (European Patent No. 0388768) is particularly used as a material for the light emitting layer.
It is preferable to use those disclosed in Japanese Patent Application Laid-Open No. HEI 3-231970. As a specific example,
4'-bis (2,2-di-t-butylphenylvinyl)
Biphenyl, 4,4′-bis (2,2-diphenylvinyl) biphenyl, and the like, and derivatives thereof can be given.

Further, Japanese Patent Application Laid-Open No. Hei 5-258882, etc.
General formula (Rs-Q) described _Two-Al-OL
[Wherein L is a carbon atom containing 6 to 2 carbon atoms containing a phenyl moiety.
4 hydrocarbons, OL is a phenolate ligand
And Q represents a substituted 8-quinolinolate ligand;
Is a substituted 8-quinolinolate ligand at the aluminum atom
Chosen to sterically hinder the binding of more than two
8-quinolinolate ring substituents]
Compounds are also included. Specifically, bis (2-methyl-8
-Quinolinolate) (para-phenylphenolate)
Luminium (III), bis (2-methyl-8-quinolyl)
Nolate) (1-naphtholate) aluminum (II
I) and the like.

In addition, there is a method of obtaining a mixed light emission of blue and green with high efficiency using doping according to JP-A-6-9953. In this case, the host
Examples of the light emitting material and dopant include strong fluorescent dyes ranging from blue to green, such as coumarin-based fluorescent dyes and fluorescent dyes similar to those used as the above-described host. Specifically, a luminescent material having a distyrylarylene skeleton as a host, particularly preferably 4,4'-bis (2,2-diphenylvinyl) biphenyl, a dopant as diphenylaminovinylarylene, particularly preferably, for example, N, N-diphenyl Aminovinylbenzene can be mentioned.

The light-emitting layer for emitting white light is not particularly limited, but the following can be used. One in which the energy level of each layer of the organic EL laminated structure is defined and light is emitted by utilizing tunnel injection (EP 0390551). A device utilizing a tunnel injection as in the above, and a white light emitting device is described as an example (Japanese Patent Laid-Open No. 3-23).
No. 0584).

JP-A-2-220390 and JP-A-2-21, in which a light emitting layer having a two-layer structure is described.
No. 6790). The light-emitting layer is divided into a plurality of light-emitting layers, each of which is made of a material having a different emission wavelength (Japanese Patent Laid-Open No. 4-51491). A structure in which a blue light-emitting material (fluorescence peak: 380 to 480 nm) and a green light-emitting material (480 to 580 nm) are laminated and further containing a red phosphor (Japanese Patent Application Laid-Open No. 6-2071).
No. 70).

A structure in which the blue light emitting layer contains a blue fluorescent dye, the green light emitting layer has a region containing a red fluorescent dye, and further contains a green phosphor (Japanese Patent Laid-Open No. 7-1421)
No. 69). Among these, those having the above configuration are particularly preferable. Further, as the red phosphor, those shown below are preferably used.

[0043]

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Next, as a method of forming a light emitting layer using the above materials, for example, a vapor deposition method, a spin coating method, an LB
A known method such as a method can be applied. The light emitting layer is
In particular, a molecular deposition film is preferable. Here, the molecular deposition film refers to a thin film formed by deposition from a material compound in a gaseous state or a film formed by solidification from a material compound in a solution state or a liquid phase state. Can be distinguished from a thin film (molecule accumulation film) formed by the LB method by a difference in an aggregated structure and a higher-order structure and a functional difference caused by the difference.

As disclosed in JP-A-57-51781, a binder such as a resin and a material compound are dissolved in a solvent to form a solution, which is then thinned by spin coating or the like. By doing so, the light emitting layer can be formed. The thickness of the light emitting layer formed in this manner is not particularly limited and can be appropriately selected depending on the situation, but is usually preferably in the range of 5 nm to 5 μm. The light-emitting layer may be composed of one or more of the above-mentioned materials, or may be a laminate of light-emitting layers made of a different kind of compound from the light-emitting layer.

Next, the hole injecting / transporting layer is a layer which assists hole injection into the light emitting layer and transports it to the light emitting region.
V or less. As such a hole injecting / transporting layer, a material that transports holes to the light emitting layer with a lower electric field strength is preferable, and the mobility of holes is, for example, 10 ⁴ to 10 ⁶ V.
/ Cm when applying an electric field of at least 10 ⁻⁶⁶ cm ² / V
-Seconds are preferred. The material for forming the hole injecting / transporting layer by mixing with the aromatic hydrocarbon compound of the present invention is not particularly limited as long as it has the preferable properties described above. Any material can be selected from those commonly used as a transport material and known materials used in a hole injection layer of an organic EL device.

As a material for forming such a hole injection / transport layer, specifically, for example, a triazole derivative (see US Pat. No. 3,112,197) and an oxadiazole derivative (US Pat. 189,447), imidazole derivatives (JP-B-37-16096)
And polyarylalkane derivatives (US Pat. Nos. 3,615,402 and 3,820,98).
No. 9, 3,542, 544, JP-B-45-555, JP-B-51-10983, JP-A-51-93224, JP-A-55-17105, and 56- Nos. 4148, 55-108667, 55-15653, and 56-3665.
No. 6), pyrazoline derivatives and pyrazolone derivatives (U.S. Pat. Nos. 3,180,729 and 4,278,746; JP-A-55-88064).
JP-A-55-88065 and JP-A-49-1055.
Nos. 37, 55-51086, 56-80
No. 051, No. 56-88141, No. 57-4
Nos. 5545, 54-112637 and 55
-74546, etc.) and phenylenediamine derivatives (U.S. Pat. No. 3,615,404, JP-B-5).
Nos. 1-10105, 46-3712, and 4
JP-A-7-25336, JP-A-54-53435, JP-A-54-110536, and JP-A-54-11992
5 and the like, an arylamine derivative (US Pat. Nos. 3,567,450 and 3,180,703).
No. 3,240,597, No. 3,
Nos. 658,520, 4,232,103, 4,175,961, and 4,011.
2,376, JP-B-49-35702,
JP-A-39-27577, JP-A-55-144250.
JP-A-56-119132, JP-A-56-224
No. 37, West German Patent No. 1,110,518), amino-substituted chalcone derivatives (US Pat.
26,501), oxazole derivatives (disclosed in U.S. Pat. No. 3,257,203) and styrylanthracene derivatives (JP-A-56-46).
234), fluorenone derivatives (Japanese Unexamined Patent Publication No.
4-110837), hydrazone derivatives (U.S. Pat. No. 3,717,462;
-59143, 55-52063, 5
No. 5-52064, No. 55-46760, No. 55-85495, No. 57-11350,
JP-A-57-148749, JP-A-2-311591
And stilbene derivatives (JP-A-61-21).
No. 0363, No. 61-228451, No. 6
1-114642, 61-72255, 62-47646, 62-36674,
JP-A-62-10652, JP-A-62-30255, JP-A-60-93455, JP-A-60-94462, JP-A-60-174747, and JP-A-60-1750
52, etc.), silazane derivatives (US Pat.
950, 950), polysilanes (Japanese Unexamined Patent Publication No.
No. 204996), an aniline-based copolymer (Japanese Unexamined Patent Application Publication No.
JP-A-282263) and conductive polymer oligomers (especially thiophene oligomers) disclosed in JP-A-1-211399.

As the material for the hole injecting / transporting layer, those described above can be used. Porphyrin compounds (those disclosed in JP-A-63-2959695), aromatic tertiary amine compounds and Styrylamine compounds (US Pat. No. 4,127,412;
-27033, 54-58445, 5
4-149634, 54-64299,
No. 55-79450, No. 55-144250, No. 56-119132, No. 61-29555
No. 8, No. 61-98353, No. 63-295
No. 695) and aromatic tertiary amine compounds can also be used.

Further, for example, 4,4'-bis (N- (1-naphthyl) -N-phenyl having two condensed aromatic rings in a molecule described in US Pat. No. 5,061,569. Amino) biphenyl and JP-A-4-308688
No. 4,4 ', 4 "-tris (N- (3-methylphenyl) -N-phenylamino) triphenylamine in which three triphenylamine units described in JP-A No. Further, in addition to the above-mentioned aromatic dimethylidin-based compound shown as the material for the light emitting layer, inorganic compounds such as p-type Si and p-type SiC can also be used as the material for the hole injection / transport layer. .

In order to form the hole injecting / transporting layer, the above compound may be thinned by a known method such as a vacuum deposition method, a spin coating method, a casting method, and an LB method. In this case, the thickness of the hole injection / transport layer is not particularly limited, but is usually 5 nm to 5 μm.
If the hole injection / transport layer contains the aromatic hydrocarbon compound of the present invention in the hole transport zone, one of the above-described materials is used.
May be composed of one or more layers consisting of two or more species,
Further, a layer obtained by laminating a hole injection / transport layer composed of a compound different from the hole injection / transport layer may be used.

The organic semiconductor layer is a layer which assists hole injection or electron injection into the light emitting layer, and is 10 ^-10 S / c.
Those having a conductivity of at least m are preferred. Examples of the material for such an organic semiconductor layer include thiophene-containing oligomers, conductive oligomers such as arylamine-containing oligomers described in JP-A-8-193191, and conductive dendrimers such as arylamine-containing dendrimers. .

Next, the electron injection layer is a layer which assists the injection of electrons into the light emitting layer, and has a high electron mobility. It is a layer made of a good material. As a material used for the electron injection layer, a metal complex of 8-hydroxyquinoline or a derivative thereof is preferable. As a specific example of the metal complex of 8-hydroxyquinoline or a derivative thereof, a metal chelate oxinoid compound containing a chelate of oxine (generally 8-quinolinol or 8-hydroxyquinoline), for example, tris (8-quinolinol) aluminum is electron-injected. It can be used as a material.

The oxadiazole derivatives include the following general formulas [8] to [10]:

[0054]

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[Wherein Ar ¹ , Ar ² , Ar ³ , A
r ⁵ , Ar ⁶ , and Ar ⁹ each independently represent a substituted or unsubstituted aryl group, and may be the same or different from each other. Ar ⁴ , Ar ⁷ , and Ar ⁸ are
Each independently represents a substituted or unsubstituted arylene group, which may be the same or different. ] The electron transfer compound represented by these is mentioned.

The aryl group in the general formulas [8] to [10] includes a phenyl group, a biphenyl group, an anthranyl group, a perylenyl group and a pyrenyl group. Examples of the arylene group include a phenylene group, a naphthylene group, a biphenylene group, an anthranylene group, a perylenylene group, and a pyrenylene group. Examples of the substituent on these include an alkyl group having 1 to 10 carbon atoms, an alkoxy group having 1 to 10 carbon atoms, and a cyano group. As the electron transfer compound, those having good thin film forming properties are preferably used.

Specific examples of these electron transfer compounds include the following.

[0058]

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Next, as a cathode, a metal, an alloy, an electrically conductive compound and a mixture thereof having a small work function (4 eV or less) as an electrode material are used. Specific examples of such an electrode material include sodium, sodium-potassium alloy, magnesium, lithium, magnesium-silver alloy, aluminum / aluminum oxide, aluminum-lithium alloy, indium, and rare earth metals. This cathode can be manufactured by forming a thin film from these electrode substances by a method such as vapor deposition or sputtering.

Here, when the light emitted from the light emitting layer is taken out from the cathode, it is preferable that the transmittance of the cathode with respect to the emitted light is larger than 10%. Further, the sheet resistance as the cathode is preferably several hundred Ω / □ or less, and the film thickness is usually 10
nm to 1 μm, preferably 50 to 200 nm. Next, with respect to the method for producing the organic EL device of the present invention, an anode, a light emitting layer, a hole injection layer if necessary, and an electron injection layer if necessary are formed by the above materials and methods. A cathode may be formed. Further, the organic EL device can be manufactured in the reverse order from the cathode to the anode.

Hereinafter, an example of manufacturing an organic EL device having a structure in which an anode / a hole injection layer / a light emitting layer / an electron injection layer / a cathode is provided in this order on a light transmitting substrate will be described. First, a thin film made of an anode material is formed on a suitable light-transmitting substrate so as to have a thickness of 1 μm or less, preferably in a range of 10 to 200 nm.
An anode is formed by an evaporation method or a sputtering method. Next, a hole injection layer is provided on the anode. As described above, the hole injection layer can be formed by a method such as a vacuum evaporation method, a spin coating method, a casting method, and an LB method. However, a uniform film is easily obtained and pinholes are not easily generated. From the viewpoint of the above, it is preferable to form by a vacuum evaporation method. When the hole injection layer is formed by a vacuum evaporation method, the deposition conditions vary depending on the compound to be used (the material of the hole injection layer), the crystal structure and the recombination structure of the target hole injection layer, etc. Source temperature 50 to 450 ° C., degree of vacuum 10 ⁻⁷ to 10 ⁻³ torr, deposition rate 0.01 to 50
nm / sec, substrate temperature -50 to 300 ° C, film thickness 5 nm to 5
It is preferable to appropriately select within the range of μm.

Next, a light emitting layer is provided on the hole injection layer. This light emitting layer can also be formed by thinning the organic light emitting material using a desired organic light emitting material by a method such as a vacuum evaporation method, a sputtering method, a spin coating method, or a casting method, but a uniform film is obtained. It is preferable to form them by a vacuum deposition method from the viewpoint that they are easily formed and pinholes are hardly generated. When the light emitting layer is formed by a vacuum deposition method, the deposition conditions vary depending on the compound used, but can be generally selected from the same condition range as the formation of the hole injection layer.

Next, an electron injection layer is provided on the light emitting layer. In this case as well, like the hole injection layer and the light emitting layer, it is preferable to form the film by a vacuum evaporation method because it is necessary to obtain a uniform film. The deposition conditions can be selected from the same condition ranges as for the hole injection layer and the light emitting layer. The aromatic hydrocarbon compound of the present invention varies depending on which of the organic compound layers is contained, but when a vacuum evaporation method is used, co-evaporation with another material can be performed. When the spin coating method is used, it can be contained by mixing with another material.

Finally, an organic EL element can be obtained by laminating a cathode. The cathode is made of a metal, and an evaporation method or sputtering can be used. However, in order to protect the underlying organic layer from damage during film formation, a vacuum deposition method is preferable. The production of the above organic EL element is as follows.
It is preferable to produce from the anode to the cathode consistently by one evacuation.

When a DC voltage is applied to the organic EL device, light emission can be observed by applying a voltage of 5 to 40 V with the anode having a positive polarity and the cathode having a negative polarity. Also, even if a voltage is applied in the opposite polarity, no current flows and no light emission occurs.
Further, when an AC voltage is applied, uniform light emission is observed only when the anode has a positive polarity and the cathode has a negative polarity. In this case, the waveform of the applied AC may be arbitrary.

[0066]

Next, the present invention will be described in more detail with reference to examples. Example 1 1 kg of α-bromodiphenylmethane and 1 kg of triethyl phosphite were charged into a reactor, heated to 100 ° C., and reacted for 3 hours. After the completion of the reaction, low-boiling substances were distilled off under reduced pressure to obtain 1.3 kg of a phosphate ester.

Then, the phosphoric acid ester, 700 g of p-bromobenzaldehyde and 4 liters of dimethyl sulfoxide as a solvent were charged into a reactor, and potassium-t-
450 g of butoxide was added little by little and reacted for 18 hours. After completion of the reaction, the product was poured into 6 liters of water, and the precipitated crystals were collected by filtration. The crystals were purified by a silica gel column to obtain 1 kg of 4- (2,2-diphenylvinyl) -1-bromobenzene.

Next, 1 g of magnesium powder and 20 ml of tetrahydrofuran were charged into a reactor under an argon stream, and 10 g of 4- (2,2-diphenylvinyl) -1-bromobenzene obtained above was added to 50 g of tetrahydrofuran. A solution dissolved in milliliter was added dropwise, and reacted for 3 hours under heating and refluxing to obtain a reaction solution (A).

Next, 1 g of 1,8,9-trihydroxyanthracene (manufactured by Tokyo Chemical Industry Co., Ltd.), 1 g of nickel acetylacetonate dihydrate (manufactured by Tokyo Chemical Industry Co., Ltd.), and 100 ml of tetrahydrofuran as a solvent were charged into the reactor. The reaction solution (A) obtained above is added dropwise thereto,
The reaction was carried out for 12 hours while heating under reflux. The reaction product obtained here was poured into 200 g of water, and the precipitated crystals were collected by filtration. The crystals were purified on a silica gel column to give 0.7
5 g of solid was obtained.

As a result of FD-MS measurement of the obtained solid, a peak of 712 was obtained for C ₅₆ H ₄₀ = 712. Therefore, the compound obtained here is
The compound was recognized to be an aromatic hydrocarbon compound having the following chemical structure. The glass transition temperature (Tg) of the aromatic hydrocarbon compound measured was 111 ° C.

[0071]

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Example 2 50 g of o-dibromobenzene (manufactured by Tokyo Chemical Industry Co., Ltd.) was added to 700 ml of 1,2-dichloroethane.
Was dissolved, and 120 g of anhydrous aluminum chloride was added thereto. Further, 200 g of 4-bromophthalic anhydride (manufactured by Tokyo Chemical Industry Co., Ltd.) was added little by little, and the mixture was reacted at room temperature for 2 hours. After completion of the reaction, the reaction solution was poured into ice water and extracted with chloroform. After the obtained product was dried over anhydrous magnesium sulfate, the solvent was distilled off to obtain a ketone body.

Then, 2 liters of polyphosphoric acid was added at 150 ° C.
, And the ketone body obtained above was added little by little, and the mixture was reacted with stirring for 3 hours. Thereafter, the reaction solution was poured into ice, and the precipitated crystals were collected by filtration and purified by column to obtain 2,3,6-tribromo-9,10-anthraquinone (32 g). Next, under an argon stream,
(2,2-diphenylvinyl) -1-bromobenzene 1
0 g was suspended in a mixture of 50 ml of toluene and 50 ml of ether, and 20 ml of a 1.54 molar hexane solution of butyllithium was added dropwise under ice cooling to obtain a reaction solution (B).

Then, 1 g of 2,3,6-tribromo-9,10-anthraquinone was placed in another reactor, and
The reaction solution (B) obtained above was added under ice cooling, and the mixture was reacted at room temperature with stirring for 12 hours. Thereafter, the reaction product was charged with water, washed with dilute hydrochloric acid, dried over anhydrous magnesium sulfate, and the solvent was distilled off. Next, after dissolving the obtained product in 200 ml of tetrahydrofuran, 80 ml of concentrated hydrochloric acid was added dropwise, 10 g of stannous chloride dihydrate was added, and the mixture was reacted for 12 hours. After completion of the reaction, the reaction solution was poured into water, and the precipitated crystals were collected by filtration, dried over anhydrous magnesium sulfate, and the solvent was distilled off. Next, column purification was performed to obtain 1 g of a solid of the target compound.

As a result of FD-MS measurement of the obtained solid, 1042 was obtained for C ₈₂ H ₅₈ = 1040.
A peak of (M + 1) was obtained. Therefore, the compound obtained here was recognized to be an aromatic hydrocarbon compound having the following chemical structure. The glass transition temperature (Tg) measured for this aromatic hydrocarbon compound is:
156 ° C.

[0076]

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Example 3 20 g of magnesium powder and 400 ml of tetrahydrofuran were charged into a reactor under an argon stream, and a solution prepared by dissolving 100 g of 3,5-dimethyl-bromobenzene (Tokyo Kasei Co., Ltd.) in 500 ml of tetrahydrofuran was added thereto. The mixture was added dropwise and reacted for 3 hours while heating under reflux to obtain a reaction liquid (C).

Next, 10 g of 9,10-dibromoanthracene (manufactured by Tokyo Chemical Industry Co., Ltd.) and 1000 g of tetrahydrofuran
Milliliter was charged into a reactor, and the reaction solution (C) obtained above was added dropwise thereto, and the mixture was reacted for 12 hours under heating and reflux. Thereafter, the obtained reaction solution was poured into 2000 g of water, and the precipitated crystals were collected by filtration. Then, the crystals were purified by a silica gel column, and 9,10-bis- (3,5-
5.3 g of (dimethylphenyl) anthracene were obtained.

Then, the obtained 9,10-bis- (3,
5-Dimethylphenyl) anthracene was suspended in 100 ml of carbon tetrachloride, and 12 g of N-bromosuccinimide (manufactured by Tokyo Kasei) and 1 g of azobisisobutyronitrile (manufactured by Tokyo Kasei) were suspended therein. In addition, the mixture was reacted for 2 hours while stirring under reflux. Thereafter, the obtained reaction solution was poured into 300 ml of methanol, and the precipitated crystals were collected by filtration to obtain 9,10-methanol.
4.2 g of bis- (3,5-dibromomethylphenyl) anthracene were obtained.

Next, the 9,10- obtained above was placed in a reactor.
1 g of bis- (3,5-dibromomethylphenyl) anthracene and 3 g of triethyl phosphite were charged,
And reacted for 3 hours. After completion of the reaction, low-boiling substances were distilled off under reduced pressure to obtain 1.5 g of a phosphoric ester. Then
This phosphate ester, 1.5 g of benzophenone (manufactured by Tokyo Chemical Industry Co., Ltd.) and 50 ml of dimethyl sulfoxide were charged, and 1 g of potassium tert-butoxide was added thereto.
Was added and reacted at room temperature for 12 hours with stirring. Then, the obtained reaction solution was poured into 100 ml of methanol, and the precipitated crystals were collected by filtration and further purified by a silica gel column to obtain 0.4 g of a solid of the target compound.

[0081] per Here resulting solid result of the measurement of the FD-MS, with respect to C ₈₀ H ₅₈ = 1018, 1019
A peak of (M + 1) was obtained. Therefore, the compound obtained here was recognized to be an aromatic hydrocarbon compound having the following chemical structure. The glass transition temperature (Tg) measured for this aromatic hydrocarbon compound is:
144 ° C.

[0082]

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Example 4 A glass substrate (size: 25 mm × 75 mm × 1.1) was used as a light-transmitting substrate of an organic EL device.
mm). On this glass substrate, a transparent anode made of indium tin oxide was provided. The transparent anode was coated to a thickness of about 750 angstroms.

Then, the glass substrate provided with the transparent anode was placed in a vacuum evaporation apparatus (manufactured by Nippon Vacuum Engineering Co., Ltd.) and
The pressure was reduced to 0 ^-6 torr. Then, on this transparent anode, copper phthalocyanine was deposited to a thickness of 300 Å to form a hole injection layer. The deposition rate at this time was 2 Å / sec. Next, on this hole injection layer,

[0085]

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The compound of the formula (1) was deposited to a thickness of 200 angstroms to form a hole transport layer. The deposition rate at this time was 2 Å / sec. Then, the aromatic hydrocarbon compound obtained in Example 1 and the following

[0087]

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The compound was co-evaporated to form a light emitting layer having a thickness of 400 angstroms. In this case, the deposition rate of the aromatic hydrocarbon compound obtained in Example 1 was set to 50 Å / sec,
The deposition rate of bis [2- (4- (N, N-diphenylamino) phenyl) vinyl] biphenyl was 1 Å / sec.

Further, tris (8-
(Quinolinol) aluminum was deposited at a deposition rate of 2 Å / sec to form an electron transport layer. Finally, a cathode having a thickness of 2000 Å was formed on the electron transporting layer by simultaneously vapor-depositing aluminum and lithium. The aluminum deposition rate was 10 angstroms / second, and the lithium deposition rate was 0.1 angstroms / second.

The thus obtained organic EL device was
When driven at a voltage of 6 V, the current density was 1.1 mA.
/ Cm ² , and emitted blue light of 108 cd / m ² . The luminous efficiency in this case is 5.1 lumen /
W. Further, the organic EL device was stored in an atmosphere at 105 ° C. for 100 hours, and then returned to room temperature.
When driven again at a voltage of 6 V, no change was observed in the luminous efficiency.

[Example 5] In Example 4, the aromatic hydrocarbon compound obtained in Example 2 was used in place of the aromatic hydrocarbon compound obtained in Example 1 used for forming the light emitting layer. In the same manner as in Example 4, an organic EL device was produced.
The organic EL device obtained here was also driven at a voltage of 6V. In this device, the current density was 1.0 mA
/ Cm ² , and emitted blue light of 105 cd / m ² . The luminous efficiency in this case is 5.5 lumen /
W. Further, the organic EL device was stored in an atmosphere at 105 ° C. for 100 hours, and then returned to room temperature.
When driven again at a voltage of 6 V, no change was observed in the luminous efficiency.

[Example 6] In Example 4, the aromatic hydrocarbon compound obtained in Example 3 was used in place of the aromatic hydrocarbon compound obtained in Example 1 used for forming the light emitting layer. In the same manner as in Example 4, an organic EL device was produced.
The organic EL device obtained here was also driven at a voltage of 6V. In this device, the current density is 1.1 mA
/ Cm ² , and emitted blue light of 107 cd / m ² . The luminous efficiency in this case is 5.1 lumen /
W. Further, the organic EL device was stored in an atmosphere at 105 ° C. for 100 hours, and then returned to room temperature.
When driven again at a voltage of 6 V, no change was observed in the luminous efficiency.

Comparative Example 1 In place of the aromatic hydrocarbon compound obtained in Example 1 used in forming the light emitting layer in Example 4, the following

[0094]

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An organic EL device was prepared in the same manner as in Example 4 except that the compound of Example 4 was used. Organic EL obtained here
When the device was driven at a voltage of 6 V, the current density was 1.
It was ² mA / cm ² and emitted blue light of 113 cd / m ² . The luminous efficiency in this case was 4.9 lumen / W. Further, the organic EL device was heated at 105 ° C.
After storing for 100 hours in the atmosphere described above, the temperature was returned to room temperature, and driving was performed again at a voltage of 6 V. As a result, the emission color became longer, and the emission efficiency was reduced by 30%.

Comparative Example 2 Instead of the aromatic hydrocarbon compound obtained in Example 1 used for forming the light emitting layer in Example 4, the following

[0097]

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An organic EL device was produced in the same manner as in Example 4 except that the compound of Example 4 was used. Organic EL obtained here
When the device was driven at a voltage of 6 V, the current density was 1.
It was 3 mA / cm ² and emitted blue light of 67 cd / m ² . The luminous efficiency in this case was 2.7 lumen / W. Further, the organic EL device was stored in an atmosphere at 105 ° C. for 100 hours, returned to room temperature, and again driven at a voltage of 6 V. As a result, no change was observed in the luminous efficiency.

[0099]

The aromatic hydrocarbon compound of the present invention is highly useful as a constituent material of an organic EL device, and the organic EL device prepared using the compound as a constituent material of the organic EL device has a low usefulness. Voltage driving is possible, and high luminous efficiency is obtained.

Claims (4)

[Claims] 1. An aromatic hydrocarbon compound represented by any one of the following general formulas [1] to [3]. Embedded image [In the formulas [1] to [3], Ar ^{1 to} Ar ⁵ are a hydrocarbon group having 5 to 40 nucleus atoms which may have a substituent;
Is an integer of 1 to 3, p is an integer of 3 to 8, q is an integer of 0 to 2, r is an integer of 0 to 4, and (q + r) is an integer of 3 to 8, and X is the following general formula: [4], embedded image (In the formula [4], R ¹ and R ² are each independently a hydrocarbon group having 5 to 40 nucleus atoms which may have a substituent.) ] 2. An organic electroluminescent device having an organic light emitting layer sandwiched between at least a pair of electrodes, wherein the aromatic hydrocarbon compound is represented by any one of the general formulas [1] to [3]. The organic electroluminescent element containing. 3. The organic electroluminescence device according to claim 2, wherein the aromatic hydrocarbon compound represented by any one of the general formulas [1] to [3] is mainly contained in a light emission band. 4. The organic electroluminescent device according to claim 2, wherein the aromatic hydrocarbon compound represented by any one of the general formulas [1] to [3] is contained in an organic light emitting layer.