JP2012222269A - Organic electroluminescent element, method for manufacturing the same, lighting device, and display device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an organic electroluminescent element which exhibits high charge injection/transport performance, shows little change in driving voltage over time, and has a long service life, and to provide a method for manufacturing the same, a lighting device, and a display device.SOLUTION: The organic electroluminescent element comprises a plurality of organic compound layers which are held between an anode and a cathode and include a hole transport layer, a light-emitting layer, and an electron transport layer. The organic electroluminescent element is characterized in that at least one of the organic compound layers contains a cyclic oligonaphthalene compound represented by general formula (1).

Description

  The present invention relates to an organic electroluminescence element, a method for manufacturing the same, a lighting device, and a display device.

  An organic electroluminescence element (hereinafter also referred to as an organic EL element) is an all-solid-state element composed of an organic material film having a thickness of only about 0.1 μm between electrodes and emits light of 2 to 20 V. Since it can be achieved at a relatively low voltage, it is a technology expected as a next-generation flat display and illumination.

  The discovery of an organic EL device using phosphorescence emission enables a light emission efficiency of about 4 times in principle compared to the previous method using fluorescence emission. Research and development relating to the structure is performed all over the world (for example, see Patent Document 1 and Non-Patent Documents 1 to 3).

  Although this is a very high potential method, the organic EL device using phosphorescence emission is greatly different from the organic EL device using fluorescence emission, and the method for controlling the position of the emission center, particularly the emission layer, is particularly different. An important technical issue in capturing the efficiency and lifetime of the device is how to recombine inside to stably emit light.

  Therefore, in recent years, there has been a multilayer stack type element comprising a hole transport layer located on the anode side of the light emitting layer and an electron transport layer located on the cathode side of the light emitting layer, in a form adjacent to the light emitting layer. It has come to be used (for example, refer to Patent Document 2).

  However, from the viewpoint of charge injection / transport properties, particularly voltage change during constant current driving, etc., it is still not sufficient, and further improvements are required.

US Pat. No. 6,097,147 JP 2005-112765 A

M.M. A. Baldo et al. , Nature, 395, 151-154 (1998) M.M. A. Baldo et al. , Nature, 403, 17, 750-753 (2000) S. Lamansky et al. , J .; Am. Chem. Soc. 123, 4304 (2001)

  The present invention has been made in view of the above-mentioned problems, and its purpose is high in charge injection / transport performance, little change in driving voltage with time, and long-life organic electroluminescence element, method for producing the same, lighting device, and It is to provide a display device.

  The above object of the present invention is achieved by the following configurations.

  1. In an organic electroluminescence device having a plurality of organic compound layers including a hole transport layer, a light emitting layer, and an electron transport layer sandwiched between an anode and a cathode, at least one of the organic compound layers is represented by the following general formula (1) The organic electroluminescent element characterized by containing the cyclic oligo naphthalene compound represented by these.

(In the formula, A _{1 to} A ₆ each independently represent CR ₁ to CR ₆ or a nitrogen atom. R _{1 to} R ₆ each independently represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, Alkylthio group, aryl group, aryloxy group, arylthio group, arylalkyl group, arylalkoxy group, arylalkylthio group, arylalkenyl group, arylalkynyl group, heteroaryl group, heteroaryloxy group, heteroarylthio group, heteroarylalkyl Group, heteroarylalkoxy group, heteroarylalkylthio group, heteroarylalkenyl group, heteroarylalkynyl group, amino group, substituted amino group, silyl group, substituted silyl group, halogen atom, acyl group, acyloxy group, imine residue, amide Group, acid imide group A monovalent heterocyclic group, carboxyl group, substituted carboxyl group, a cyano group or a nitro group, _{R 1} and _R 2, _{R 3} and _R 4, _{R 4} and _{R 5} and _{R 5} and _{R 6} are respectively bonded to each other And n may be an integer of 3 to 10.)
2. 2. The organic electroluminescence device according to 1 above, wherein the organic compound layer containing the cyclic oligonaphthalene compound is a light emitting layer.

  3. 2. The organic electroluminescence device according to 1 above, wherein the organic compound layer containing the cyclic oligonaphthalene compound is a hole transport layer.

  4). 2. The organic electroluminescence device according to 1 above, wherein the organic compound layer containing the cyclic oligonaphthalene compound is an electron transport layer.

  5). 3. The organic electroluminescence device according to 2 above, wherein the light emitting layer contains a phosphorescent organic metal complex compound, and at least one of them is a compound represented by the following general formula (2).

(In the formula, P and Q represent a carbon atom or a nitrogen atom, A1 represents an atomic group which forms an aromatic hydrocarbon ring or an aromatic heterocycle with PC, and A2 represents an aromatic hydrocarbon with QN. P1-L1-P2 represents a bidentate ligand, P1 and P2 each independently represent a carbon atom, a nitrogen atom, or an oxygen atom, and L1 represents P1. , P2 represents an atomic group forming a bidentate ligand, r represents an integer of 1 to 3, s represents an integer of 0 to 2, and r + s is 2 or 3. M ₁ is an element Represents a group 8-10 metal element in the periodic table.)
6). 4. The organic electroluminescence device according to 3 above, wherein the hole transport layer contains an acceptor material.

  7). 5. The organic electroluminescence device as described in 4 above, wherein the electron transport layer contains a donor material.

  8). An illuminating device comprising the organic electroluminescent element according to any one of 1 to 7 above.

  9. A display device comprising the organic electroluminescence element according to any one of 1 to 7 above.

  10. 8. The method for producing an organic electroluminescence device according to any one of 1 to 7, wherein a layer containing the cyclic oligonaphthalene compound represented by the general formula (1) in the organic layer is a wet method (wet method). A process for producing an organic electroluminescent element, wherein the film is formed and formed by a process.

  According to the present invention, an organic electroluminescence element having high charge injection / transport performance, little change in driving voltage with time, and a long lifetime, a manufacturing method thereof, an illumination device, and a display device can be provided.

It is the schematic diagram which showed an example of the display apparatus comprised from an organic EL element. 4 is a schematic diagram of a display unit A. FIG. It is a schematic diagram of a pixel. It is a schematic diagram of a passive matrix type full-color display device. It is the schematic of an illuminating device. It is a schematic diagram of an illuminating device. It is a schematic block diagram of an organic EL full-color display device.

  Hereinafter, the best mode for carrying out the present invention will be described in detail, but the present invention is not limited thereto.

  Hereinafter, details of each component according to the present invention will be sequentially described.

<< Cyclic oligonaphthalene compound represented by the general formula (1) >>
The present invention is characterized in that at least one of the organic compound layers contains a cyclic oligonaphthalene compound represented by the general formula (1).

In the general formula (1), A _{1 to} A ₆ each independently represent CR ₁ to CR ₆ or a nitrogen atom. R _{1 to} R ₆ are each independently a hydrogen atom, alkyl group, alkenyl group, alkynyl group, alkoxy group, alkylthio group, aryl group, aryloxy group, arylthio group, arylalkyl group, arylalkoxy group, arylalkylthio group, Arylalkenyl group, arylalkynyl group, heteroaryl group, heteroaryloxy group, heteroarylthio group, heteroarylalkyl group, heteroarylalkoxy group, heteroarylalkylthio group, heteroarylalkenyl group, heteroarylalkynyl group, amino group, Substituted amino group, silyl group, substituted silyl group, halogen atom, acyl group, acyloxy group, imine residue, amide group, acid imide group, monovalent heterocyclic group, carboxyl group, substituted carboxyl group, cyano group or nitro group Represents, _{R 1} and _R 2, _{R 3} and _R 4, _{R 4} and _{R 5} and _{R 5} and _{R 6} may each be bonded to each other to form a ring. n represents an integer of 3 to 10.

Examples of the alkyl group include a methyl group, an ethyl group, a propyl group, an isopropyl group, a tert-butyl group, a pentyl group, a hexyl group, an octyl group, a dodecyl group, a tridecyl group, a tetradecyl group, and a pentadecyl group.
Examples of the alkenyl group include a vinyl group and an allyl group.
Examples of the alkynyl group include ethynyl group, propargyl group, etc.
Examples of the alkoxy group include, for example, methoxy group, ethoxy group, propyloxy group, pentyloxy group, hexyloxy group, octyloxy group, dodecyloxy group, etc.
Examples of the alkylthio group include, for example, a methylthio group, an ethylthio group, a propylthio group, a pentylthio group, a hexylthio group, an octylthio group, a dodecylthio group, and the like.
As the aryl group, for example, phenyl group, p-chlorophenyl group, mesityl group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl group, acenaphthenyl group, fluorenyl group, phenanthryl group, indenyl group, pyrenyl group, Biphenylyl group, etc.
Examples of the aryloxy group include a phenoxy group and a naphthyloxy group.
Examples of the arylthio group include a phenylthio group and a naphthylthio group.
Examples of the arylalkyl group include a tolyl group and an ethylphenyl group.
As the arylalkoxy group, for example, a methoxyphenyl group, an ethoxyphenyl group, etc.
As the arylalkylthio group, for example, methylthiophenyl group, ethylthiophenyl group, etc.
Examples of the arylalkenyl group include a styryl group and an allylphenyl group.
As the arylalkynyl group, for example, ethynylphenyl group, propargylphenyl group, etc.
Examples of the heteroaryl group include a pyridyl group, a pyrimidinyl group, a furyl group, a pyrrolyl group, an imidazolyl group, a benzoimidazolyl group, a pyrazolyl group, a pyrazinyl group, and a triazolyl group (for example, 1,2,4-triazol-1-yl group, 1,2,3-triazol-1-yl group, etc.), oxazolyl group, benzoxazolyl group, thiazolyl group, isoxazolyl group, isothiazolyl group, furazanyl group, thienyl group, quinolyl group, benzofuryl group, dibenzofuryl group, benzo A thienyl group, a dibenzothienyl group, an indolyl group, a carbazolyl group, a carbolinyl group, a diazacarbazolyl group (indicating that one of the carbon atoms constituting the carboline ring of the carbolinyl group is replaced by a nitrogen atom), a quinoxalinyl group, Pyridazinyl group, triazinyl group, Nazoriniru group, a phthalazinyl group, and the like,
Examples of the heteroaryloxy group include a pyridinoxy group and a pyrimidinoxy group.
Examples of the heteroarylthio group include a pyridylthio group and a quinolylthio group.
Examples of the heteroarylalkyl group include a methylpyridyl group, an ethylpyridyl group,
Examples of the heteroarylalkoxy group include a methoxypyridyl group and an ethoxypyridyl group.
Examples of the heteroarylalkylthio group include a pyridylthio group and a quinolylthio group.
Examples of the heteroarylalkenyl group include a vinylpyridyl group and an allylpyridyl group.
Examples of the heteroarylalkynyl group include ethynylpyridyl group, propargylpyridyl group, etc.
Examples of the substituted amino group include an amino group, an ethylamino group, a dimethylamino group, a butylamino group, a cyclopentylamino group, a 2-ethylhexylamino group, a dodecylamino group, an anilino group, a naphthylamino group, and a 2-pyridylamino group.
Examples of the substituted silyl group include trimethylsilyl group, triisopropylsilyl group, triphenylsilyl group, phenyldiethylsilyl group, etc.
Examples of the halogen atom include a fluorine atom, a chlorine atom, and a bromine atom.
As the acyl group, for example, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, octylcarbonyl group, 2-ethylhexylcarbonyl group, dodecylcarbonyl group, phenylcarbonyl group, naphthylcarbonyl group, A pyridylcarbonyl group etc. are mentioned.

  In addition, these substituents may be further substituted with the above substituents. In addition, a plurality of these substituents may be bonded to each other to form a ring.

  Although the specific example of a compound represented by General formula (1) in this invention is shown below, this invention is not limited to these.

  Examples of methods for forming organic compound layers such as a hole transport layer, a light emitting layer, and an electron transport layer using the compound represented by the general formula (1) include vapor deposition, spin coating, casting, and LB. Although it can be formed by thinning by a known method such as a method, a molecular deposition film is particularly preferable. Here, the molecular deposited film is a thin film formed by deposition from the gas phase state of the compound or a film formed by solidification from the molten state or liquid state of the compound. Normally, this molecular deposited film can be distinguished from a thin film (molecular accumulated film) formed by the LB method, a difference in aggregation structure, a higher order structure, and a functional difference resulting therefrom.

<< Constitutional layer of organic EL element, organic compound layer >>
The constituent layers and organic compound layers of the organic EL device of the present invention will be described. Although the preferable specific example of the layer structure of the organic EL element of this invention is shown below, this invention is not limited to these.

(I) Anode / hole transport layer / light emitting layer / electron transport layer / cathode (ii) Anode / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / cathode (iii) Anode / hole transport layer / Light emitting layer / hole blocking layer / electron transport layer / cathode buffer layer / cathode (iv) anode / anode buffer layer / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / cathode buffer layer / cathode << Organic compound layer (also called organic layer) >>
The organic compound layer according to the present invention will be described. The organic EL device of the present invention preferably has a plurality of organic compound layers as a constituent layer, and examples of the organic compound layer include a hole transport layer, a light emitting layer, and a hole blocking layer in the above-described layer configuration. As the organic compound layer according to the present invention, an organic compound contained in a constituent layer of the organic EL element, such as a hole injection layer or an electron injection layer, is included. Defined.

  Furthermore, when an organic compound is used for the anode buffer layer, the cathode buffer layer, etc., the anode buffer layer, the cathode buffer layer, etc. each form an organic compound layer.

  The organic compound layer includes a layer containing “organic EL element material that can be used for a constituent layer of an organic EL element” or the like.

  In the organic EL device of the present invention, the light emitting maximum wavelength of the blue light emitting layer is preferably 430 nm to 480 nm, the green light emitting layer has a light emitting maximum wavelength of 510 nm to 550 nm, and the red light emitting layer has a light emitting maximum wavelength of 600 nm to 640 nm. A monochromatic light emitting layer in the range is preferable, and a display device using these is preferable.

  Alternatively, a white light emitting layer may be formed by laminating at least three light emitting layers. Further, a non-light emitting intermediate layer may be provided between the light emitting layers.

  The organic EL element of the present invention is preferably a white light emitting layer, and is preferably a lighting device using these.

  Each layer which comprises the organic EL element of this invention is demonstrated.

<Light emitting layer>
The light emitting layer according to the present invention is a layer that emits light by recombination of electrons and holes injected from the electrode, the electron transport layer, or the hole transport layer, and the light emitting portion is in the layer of the light emitting layer. May be the interface between the light emitting layer and the adjacent layer.

  The total film thickness of the light emitting layer is not particularly limited, but from the viewpoint of improving the uniformity of the film, preventing unnecessary application of high voltage during light emission, and improving the stability of the emission color with respect to the drive current. It is preferable to adjust in the range of 2 nm to 5 μm, more preferably in the range of 2 to 200 nm, and particularly preferably in the range of 10 to 20 nm.

  For the production of the light-emitting layer, a light-emitting dopant or a host compound, which will be described later, is formed by a known thinning method such as a vacuum deposition method, a spin coating method, a casting method, an LB method, or an ink-jet method. it can.

  The light emitting layer of the organic EL device of the present invention preferably contains a light emitting host compound and at least one kind of light emitting dopant (phosphorescent dopant (also referred to as phosphorescent dopant) or fluorescent dopant). . Moreover, you may mix and use the hole transport material and electron transport material which are mentioned later.

(Host compound (also called luminescent host))
The host compound used in the present invention will be described. Here, the host compound in the present invention is a phosphorescent quantum yield of phosphorescence emission at a room temperature (25 ° C.) having a mass ratio of 20% or more in the compound contained in the light emitting layer. Is defined as a compound of less than 0.1. The phosphorescence quantum yield is preferably less than 0.01. Moreover, it is preferable that the mass ratio in the layer is 20% or more among the compounds contained in a light emitting layer.

  In the present invention, the cyclic oligonaphthalene compound is particularly preferably used as a host compound.

  In addition, as a host compound, a well-known host compound may be used together, and may be used in combination of multiple types. By using a plurality of types of host compounds, it is possible to adjust the movement of charges, and the organic EL element can be made highly efficient. Moreover, it becomes possible to mix different light emission by using multiple types of light emission dopants mentioned later, and, thereby, arbitrary luminescent colors can be obtained.

  A conventionally known host compound that may be used in combination is preferably a compound that has a hole transporting ability and an electron transporting ability, prevents the emission of light from becoming longer, and has a high Tg (glass transition temperature).

  Specific examples of conventionally known host compounds include the following compounds or the compounds described in the following documents.

  JP-A-2001-257076, 2002-308855, 2001-313179, 2002-319491, 2001-357777, 2002-334786, 2002-8860, 2002-334787, 2002-15871, 2002-334788, 2002-43056, 2002-334789, 2002-75645, 2002-338579, 2002-105445 gazette, 2002-343568 gazette, 2002-141173 gazette, 2002-352957 gazette, 2002-203683 gazette, 2002-363227 gazette, 2002-231453 gazette, No. 003-3165, No. 2002-234888, No. 2003-27048, No. 2002-255934, No. 2002-286061, No. 2002-280183, No. 2002-299060, No. 2002. -302516, 2002-305083, 2002-305084, 2002-308837, and the like.

(Luminescent dopant)
The light emitting dopant according to the present invention will be described.

  As the light-emitting dopant according to the present invention, a fluorescent dopant (also referred to as a fluorescent compound) or a phosphorescent dopant (also referred to as a phosphorescent emitter, a phosphorescent compound, a phosphorescent compound, or the like) can be used. From the viewpoint of obtaining an organic EL device having higher luminous efficiency, the above-mentioned host compound may be used as the luminescent dopant (simply referred to as a luminescent material) used in the light emitting layer or the light emitting unit of the organic EL device of the present invention. It is preferable to contain a phosphorescent dopant at the same time as containing.

  (Phosphorescent compound (phosphorescent dopant)) The phosphorescent compound (phosphorescent dopant) according to the present invention will be described.

  The phosphorescent compound according to the present invention is a compound in which light emission from an excited triplet is observed. Specifically, it is a compound that emits phosphorescence at room temperature (25 ° C.) and has a phosphorescence quantum yield. The phosphorescence quantum yield is preferably 0.1 or more, although it is defined as a compound of 0.01 or more at 25 ° C.

  The phosphorescence quantum yield can be measured by the method described in Spectroscopic II, page 398 (1992 edition, Maruzen) of Experimental Chemistry Course 4 of the 4th edition. Although the phosphorescence quantum yield in a solution can be measured using various solvents, the phosphorescence emitting compound according to the present invention achieves the above phosphorescence quantum yield (0.01 or more) in any solvent. It only has to be done.

  There are two types of light emission of phosphorescent compounds. In principle, the recombination of carriers occurs on the host compound to which carriers are transported, and an excited state of the host compound is generated. This energy is phosphorescent. An energy transfer type that obtains light emission from the phosphorescent compound by transferring to the phosphorescent compound, and the other is that the phosphorescent compound becomes a carrier trap, and recombination of carriers on the phosphorescent compound is performed. And a carrier trap type in which light emission from the phosphorescent compound is obtained.

  In any of the above cases, it is a condition that the excited state energy of the phosphorescent compound is lower than the excited state energy of the host compound.

  The phosphorescent compound can be appropriately selected from known compounds used for the light emitting layer of the organic EL device.

  The phosphorescent compound according to the present invention is preferably a complex compound containing a group 8-10 metal in the periodic table, more preferably an iridium compound (Ir complex), an osmium compound, or a platinum compound ( Platinum complex compounds) and rare earth complexes, most preferably iridium compounds (Ir complexes).

<< Phosphorescent Compound Represented by Formula (2) >>
As the phosphorescent compound according to the present invention, a compound represented by the general formula (2) (phosphorescent organometallic complex compound) is preferably used.

  In the general formula (2), the aromatic hydrocarbon ring represented by A1 includes a benzene ring, biphenyl ring, naphthalene ring, azulene ring, anthracene ring, phenanthrene ring, pyrene ring, chrysene ring, naphthacene ring, triphenylene ring, o-terphenyl ring, m-terphenyl ring, p-terphenyl ring, acenaphthene ring, coronene ring, fluorene ring, fluoranthrene ring, naphthacene ring, pentacene ring, perylene ring, pentaphen ring, picene ring, pyrene ring, Examples include a pyranthrene ring and anthraanthrene ring. These rings may further have a substituent described later.

  In the general formula (2), examples of the aromatic heterocycle represented by A1 include a furan ring, a thiophene ring, an oxazole ring, a pyrrole ring, a pyridine ring, a pyridazine ring, a pyrimidine ring, a pyrazine ring, a triazine ring, and a benzimidazole. Ring, oxadiazole ring, triazole ring, imidazole ring, pyrazole ring, thiazole ring, indazole ring, indazole ring, benzimidazole ring, benzothiazole ring, benzoxazole ring, quinoxaline ring, quinazoline ring, cinnoline ring, quinoline ring, isoquinoline Ring, phthalazine ring, naphthyridine ring, carbazole ring, carboline ring, diazacarbazole ring (showing a ring in which one of the carbon atoms constituting the carboline ring is further substituted with a nitrogen atom) and the like. These rings may further have a substituent described later.

(Substituent)
Examples of the substituent that the aromatic hydrocarbon ring or aromatic heterocyclic ring represented by A1 may have an alkyl group (for example, a methyl group, an ethyl group, a propyl group, an isopropyl group, a tert-butyl group) Pentyl group, hexyl group, octyl group, dodecyl group, tridecyl group, tetradecyl group, pentadecyl group, etc.), cycloalkyl group (for example, cyclopentyl group, cyclohexyl group, etc.), alkenyl group (for example, vinyl group, allyl group, etc.) Alkynyl group (for example, ethynyl group, propargyl group, etc.), aromatic hydrocarbon group (aromatic hydrocarbon ring group, aromatic carbocyclic group, aryl group, etc.), for example, phenyl group, p-chlorophenyl group, mesityl Group, tolyl group, xylyl group, naphthyl group, anthryl group, azulenyl group, acenaphthenyl group, fluorenyl group, Entanthryl group, indenyl group, pyrenyl group, biphenylyl group, etc.), aromatic heterocyclic group (for example, pyridyl group, pyrimidinyl group, furyl group, pyrrolyl group, imidazolyl group, benzoimidazolyl group, pyrazolyl group, pyrazinyl group, triazolyl group (for example, , 1,2,4-triazol-1-yl group, 1,2,3-triazol-1-yl group, etc.), oxazolyl group, benzoxazolyl group, thiazolyl group, isoxazolyl group, isothiazolyl group, furazanyl group, Thienyl group, quinolyl group, benzofuryl group, dibenzofuryl group, benzothienyl group, dibenzothienyl group, indolyl group, carbazolyl group, carbolinyl group, diazacarbazolyl group (one of the carbon atoms constituting the carboline ring of the carbolinyl group) Shows one replaced by a nitrogen atom Quinoxalinyl group, pyridazinyl group, triazinyl group, quinazolinyl group, phthalazinyl group, etc.), heterocyclic group (for example, pyrrolidyl group, imidazolidyl group, morpholyl group, oxazolidyl group, etc.), alkoxy group (for example, methoxy group, ethoxy group, propyl) Oxy group, pentyloxy group, hexyloxy group, octyloxy group, dodecyloxy group, etc.), cycloalkoxy group (eg, cyclopentyloxy group, cyclohexyloxy group, etc.), aryloxy group (eg, phenoxy group, naphthyloxy group, etc.) ), Alkylthio groups (for example, methylthio group, ethylthio group, propylthio group, pentylthio group, hexylthio group, octylthio group, dodecylthio group, etc.), cycloalkylthio groups (for example, cyclopentylthio group, cyclohexylthio group, etc.) ), Arylthio group (eg, phenylthio group, naphthylthio group, etc.), alkoxycarbonyl group (eg, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group, etc.), aryloxy Carbonyl group (for example, phenyloxycarbonyl group, naphthyloxycarbonyl group, etc.), sulfamoyl group (for example, aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group) Octylaminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc.), Sil group (for example, acetyl group, ethylcarbonyl group, propylcarbonyl group, pentylcarbonyl group, cyclohexylcarbonyl group, octylcarbonyl group, 2-ethylhexylcarbonyl group, dodecylcarbonyl group, phenylcarbonyl group, naphthylcarbonyl group, pyridylcarbonyl group, etc. ), Acyloxy groups (for example, acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group, dodecylcarbonyloxy group, phenylcarbonyloxy group, etc.), amide groups (for example, methylcarbonylamino group, ethylcarbonyl) Amino group, dimethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexylcarbonyl Mino group, octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group, etc.), carbamoyl group (for example, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentyl) Aminocarbonyl group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), ureido group (eg methyl Ureido group, ethylureido group, pentylureido group, cyclohexylureido group, octylureido group, dodecylureido group, phenylureido group naphthyl Ureido group, 2-pyridylaminoureido group, etc.), sulfinyl group (for example, methylsulfinyl group, ethylsulfinyl group, butylsulfinyl group, cyclohexylsulfinyl group, 2-ethylhexylsulfinyl group, dodecylsulfinyl group, phenylsulfinyl group, naphthylsulfinyl group, 2-pyridylsulfinyl group etc.), alkylsulfonyl group (eg methylsulfonyl group, ethylsulfonyl group, butylsulfonyl group, cyclohexylsulfonyl group, 2-ethylhexylsulfonyl group, dodecylsulfonyl group etc.), arylsulfonyl group or heteroarylsulfonyl group (For example, phenylsulfonyl group, naphthylsulfonyl group, 2-pyridylsulfonyl group, etc.), amino group (for example, amino group, ethylamino group, dimethyl) Amino group, butylamino group, cyclopentylamino group, 2-ethylhexylamino group, dodecylamino group, anilino group, naphthylamino group, 2-pyridylamino group, etc.), halogen atom (for example, fluorine atom, chlorine atom, bromine atom, etc.) , Fluorinated hydrocarbon group (for example, fluoromethyl group, trifluoromethyl group, pentafluoroethyl group, pentafluorophenyl group, etc.), cyano group, nitro group, hydroxy group, mercapto group, silyl group (for example, trimethylsilyl group, Triisopropylsilyl group, triphenylsilyl group, phenyldiethylsilyl group, etc.), phosphono group and the like.

  In addition, these substituents may be further substituted with the above substituents. In addition, a plurality of these substituents may be bonded to each other to form a ring.

  In the general formula (2), the aromatic hydrocarbon ring and aromatic heterocycle represented by A2 are respectively synonymous with the aromatic hydrocarbon ring and aromatic heterocycle represented by A1 in the general formula (1). is there.

  In the general formula (2), examples of the bidentate ligand represented by P1-L1-P2 include substituted or unsubstituted phenylpyridine, phenylpyrazole, phenylimidazole, phenyltriazole, phenyltetrazole, pyrazabol, acetylacetone. And picolinic acid.

In the general formula (2), M ₁ is a transition metal element belonging to Group 8 to 10 in the periodic table of elements (also simply referred to as a transition metal). Among them, iridium and platinum are preferable, and iridium is particularly preferable.

  Specific examples of the phosphorescent compound represented by the general formula (2) and the compound used as the phosphorescent compound are shown below, but the present invention is not limited thereto. These compounds are described, for example, in Inorg. Chem. 40, 1704-1711, etc.

(Fluorescent dopant (also called fluorescent compound))
Fluorescent dopants (fluorescent compounds) include coumarin dyes, pyran dyes, cyanine dyes, croconium dyes, squalium dyes, oxobenzanthracene dyes, fluorescein dyes, rhodamine dyes, pyrylium dyes, perylene dyes Examples thereof include dyes, stilbene dyes, polythiophene dyes, and rare earth complex phosphors.

  Next, an injection layer, a blocking layer, an electron transport layer and the like used as the constituent layers of the organic EL element of the present invention will be described.

<< Injection layer: electron injection layer, hole injection layer >>
The injection layer is provided as necessary, and there are an electron injection layer and a hole injection layer, and as described above, it exists between the anode and the light emitting layer or the hole transport layer and between the cathode and the light emitting layer or the electron transport layer. May be.

  An injection layer is a layer provided between an electrode and an organic layer in order to reduce drive voltage and improve light emission luminance. “Organic EL element and its forefront of industrialization (issued by NTT Corporation on November 30, 1998) 2), Chapter 2, “Electrode Materials” (pages 123 to 166) in detail, and includes a hole injection layer (anode buffer layer) and an electron injection layer (cathode buffer layer).

  The details of the anode buffer layer (hole injection layer) are described in JP-A-9-45479, JP-A-9-260062, JP-A-8-288069 and the like. As a specific example, copper phthalocyanine is used. Examples thereof include a phthalocyanine buffer layer represented by an oxide, an oxide buffer layer represented by vanadium oxide, an amorphous carbon buffer layer, and a polymer buffer layer using a conductive polymer such as polyaniline (emeraldine) or polythiophene.

  The details of the cathode buffer layer (electron injection layer) are described in JP-A-6-325871, JP-A-9-17574, JP-A-10-74586, and the like. Specifically, strontium, aluminum, etc. Metal buffer layer typified by lithium, alkali metal compound buffer layer typified by lithium fluoride, alkaline earth metal compound buffer layer typified by magnesium fluoride, oxide buffer layer typified by aluminum oxide, etc. . The buffer layer (injection layer) is preferably a very thin film, and the film thickness is preferably in the range of 0.1 to 10 nm although it depends on the material.

<Blocking layer: hole blocking layer, electron blocking layer>
The blocking layer is provided as necessary in addition to the basic constituent layer of the organic compound thin film as described above. For example, it is described in JP-A Nos. 11-204258, 11-204359, and “Organic EL elements and their forefront of industrialization” (issued by NTT, Inc. on November 30, 1998). There is a hole blocking (hole blocking) layer.

  The hole blocking layer has a function of an electron transport layer in a broad sense, and is made of a hole blocking material that has a function of transporting electrons and has a remarkably small ability to transport holes. The probability of recombination of electrons and holes can be improved by blocking.

  Moreover, the structure of the electron carrying layer mentioned later can be used as a hole-blocking layer concerning this invention as needed.

  The hole blocking layer of the organic EL device of the present invention is preferably provided adjacent to the light emitting layer.

  In the present invention, when a plurality of light emitting layers having different light emission colors are provided, the light emitting layer having the shortest wavelength of light emission is preferably closest to the anode among all the light emitting layers. In this case, it is preferable to additionally provide a hole blocking layer between the shortest wave layer and the light emitting layer next to the anode next to the anode.

  Furthermore, it is preferable that 50% by mass or more of the compound contained in the hole blocking layer provided at the position has an ionization potential of 0.3 eV or more larger than the host compound of the shortest wave emitting layer.

  The ionization potential is defined by the energy required to emit an electron at the HOMO (highest occupied molecular orbital) level of the compound to the vacuum level, and can be obtained by the following method, for example.

  (1) Using Gaussian 98 (Gaussian 98, Revision A.11.4, MJ Frisch, et al, Gaussian, Inc., Pittsburgh PA, 2002.), a molecular orbital calculation software manufactured by Gaussian, USA The ionization potential can be obtained as a value obtained by rounding off the second decimal place of the value (eV unit converted value) calculated by performing structural optimization using B3LYP / 6-31G *. This calculation value is effective because the correlation between the calculation value obtained by this method and the experimental value is high.

  (2) The ionization potential can also be obtained by a method of directly measuring by photoelectron spectroscopy. For example, a method known as ultraviolet photoelectron spectroscopy can be suitably used by using a low energy electron spectrometer “Model AC-1” manufactured by Riken Keiki Co., Ltd.

  On the other hand, the electron blocking layer has a function of a hole transport layer in a broad sense, and is made of a material that has a function of transporting holes and has an extremely small ability to transport electrons, and transports electrons while transporting holes. By blocking, the recombination probability of electrons and holes can be improved.

  Moreover, the structure of the positive hole transport layer mentioned later can be used as an electron blocking layer as needed. The film thickness of the hole blocking layer and the electron transport layer according to the present invention is preferably 3 nm to 100 nm, and more preferably 5 to 30 nm.

《Hole transport layer》
The hole transport layer is made of a hole transport material having a function of transporting holes, and in a broad sense, a hole injection layer and an electron blocking layer are also included in the hole transport layer. The hole transport layer can be provided as a single layer or a plurality of layers.

  The hole transport material has any one of hole injection or transport and electron barrier properties, and may be either organic or inorganic. For example, triazole derivatives, oxadiazole derivatives, imidazole derivatives, polyarylalkane derivatives, pyrazoline derivatives and pyrazolone derivatives, phenylenediamine derivatives, arylamine derivatives, amino-substituted chalcone derivatives, oxazole derivatives, styrylanthracene derivatives, fluorenone derivatives, hydrazone derivatives, Examples thereof include stilbene derivatives, silazane derivatives, aniline copolymers, and conductive polymer oligomers, particularly thiophene oligomers.

  In the present invention, the cyclic oligonaphthalene compound is particularly preferably used as a hole transport material.

  The above-mentioned materials can be used as the hole transport material, but it is preferable to use a porphyrin compound, an aromatic tertiary amine compound and a styrylamine compound, particularly an aromatic tertiary amine compound.

  Representative examples of aromatic tertiary amine compounds and styrylamine compounds include N, N, N ', N'-tetraphenyl-4,4'-diaminophenyl; N, N'-diphenyl-N, N'- Bis (3-methylphenyl)-[1,1′-biphenyl] -4,4′-diamine (TPD); 2,2-bis (4-di-p-tolylaminophenyl) propane; 1,1-bis (4-di-p-tolylaminophenyl) cyclohexane; N, N, N ′, N′-tetra-p-tolyl-4,4′-diaminobiphenyl; 1,1-bis (4-di-p-tolyl) Aminophenyl) -4-phenylcyclohexane; bis (4-dimethylamino-2-methylphenyl) phenylmethane; bis (4-di-p-tolylaminophenyl) phenylmethane; N, N'-diphenyl-N, N ' − (4-methoxyphenyl) -4,4'-diaminobiphenyl; N, N, N ', N'-tetraphenyl-4,4'-diaminodiphenyl ether; 4,4'-bis (diphenylamino) quadriphenyl; N, N, N-tri (p-tolyl) amine; 4- (di-p-tolylamino) -4 '-[4- (di-p-tolylamino) styryl] stilbene; 4-N, N-diphenylamino- (2-diphenylvinyl) benzene; 3-methoxy-4'-N, N-diphenylaminostilbenzene; N-phenylcarbazole, as well as two of those described in US Pat. No. 5,061,569 Having a condensed aromatic ring in the molecule, for example, 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD), JP-A-4-308 4,4 ', 4 "-tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine in which three triphenylamine units described in Japanese Patent No. 88 are linked in a starburst type ( MTDATA) and the like.

  Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used. In addition, inorganic compounds such as p-type-Si and p-type-SiC can also be used as the hole injection material and the hole transport material.

  JP-A-11-251067, J. Org. Huang et. al. A so-called p-type hole transport material as described in a book (Applied Physics Letters 80 (2002), p. 139) can also be used. In the present invention, since a higher performance light emitting device can be obtained, it is preferable to use the organic EL device material of the present invention containing the compound represented by the general formula (1). You may use together.

  The hole transport layer can be formed by thinning the hole transport material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an ink jet method, or an LB method. However, in the present invention, it is preferably produced by a coating method (wet process). Although there is no restriction | limiting in particular about the film thickness of a positive hole transport layer, Usually, 5 nm-about 5 micrometers, Preferably it is 5-200 nm. The hole transport layer may have a single layer structure composed of one or more of the above materials.

  Alternatively, a hole transport layer having a high p property doped with impurities can be used. Examples thereof include JP-A-4-297076, JP-A-2000-196140, 2001-102175, J. Pat. Appl. Phys. 95, 5773 (2004), and the like.

  In the present invention, it is preferable to use a hole transport layer having such a high p property because a device with lower power consumption can be produced.

The hole transport layer preferably contains an acceptor material. An acceptor material includes an n-type semiconductor material. Examples of n-type semiconductor materials include Au, Pt, W, Ir, POCl ₃ , AsF ₆ , Cl, Br, I, inorganic materials such as vanadium oxide (V ₂ O ₅ ), molybdenum oxide (MoO ₂ ), and TCNQ. Preferred examples include cyano groups and fluorine-containing compounds such as (7,7,8,8-tetracyanoquinodimethane) and F ₄ -TCNQ (tetrafluorotetracyanoquinodimethane). Also, TBPAH (tris (4-bromophenyl) aminium hexachloroantimonate), fullerene, octaazaporphyrin, p-type semiconductor perfluoro products (perfluoropentacene, perfluorophthalocyanine, etc.), naphthalenetetracarboxylic anhydride, naphthalenetetra Examples of the polymer compound include aromatic carboxylic acid anhydrides such as carboxylic acid diimide, perylene tetracarboxylic acid anhydride, and perylene tetracarboxylic acid diimide, and imidized products thereof as a skeleton.

  Among these, fullerene-containing polymer compounds are preferable. Fullerene-containing polymer compounds include fullerene C60, fullerene C70, fullerene C76, fullerene C78, fullerene C84, fullerene C240, fullerene C540, mixed fullerene, fullerene nanotubes, multi-walled nanotubes, single-walled nanotubes, nanohorns (conical), etc. Examples thereof include a polymer compound having a skeleton. As the fullerene-containing polymer compound, a polymer compound (derivative) having fullerene C60 as a skeleton is preferable.

  The fullerene-containing polymers are roughly classified into polymers in which fullerene is pendant from a polymer main chain and polymers in which fullerene is contained in the polymer main chain. Fullerene is contained in the polymer main chain. Are preferred.

《Electron transport layer》
The electron transport layer is made of a material having a function of transporting electrons, and in a broad sense, an electron injection layer and a hole blocking layer are also included in the electron transport layer. The electron transport layer can be provided as a single layer or a plurality of layers.

  Conventionally, in the case of a single electron transport layer and a plurality of layers, an electron transport material (also serving as a hole blocking material) used for an electron transport layer adjacent to the light emitting layer on the cathode side is injected from the cathode. Any material may be used as long as it has a function of transferring electrons to the light-emitting layer, and any material can be selected from conventionally known compounds.

  Examples include nitro-substituted fluorene derivatives, diphenylquinone derivatives, thiopyran dioxide derivatives, carbodiimides, fluorenylidenemethane derivatives, anthraquinodimethane and anthrone derivatives, oxadiazole derivatives, and the like.

  Furthermore, in the above oxadiazole derivative, a thiadiazole derivative in which an oxygen atom of the oxadiazole ring is substituted with a sulfur atom, or a quinoxaline derivative having a quinoxaline ring known as an electron withdrawing group can also be used as an electron transport material. Furthermore, a polymer material in which these materials are introduced into a polymer chain or these materials are used as a polymer main chain can also be used.

  In addition, metal complexes of 8-quinolinol derivatives such as tris (8-quinolinol) aluminum (Alq), tris (5,7-dichloro-8-quinolinol) aluminum, tris (5,7-dibromo-8-quinolinol) aluminum Tris (2-methyl-8-quinolinol) aluminum, tris (5-methyl-8-quinolinol) aluminum, bis (8-quinolinol) zinc (Znq), and the like, and the central metals of these metal complexes are In, Mg, Metal complexes replaced with Cu, Ca, Sn, Ga or Pb can also be used as the electron transport material.

  In addition, metal-free or metal phthalocyanine, or those having terminal ends substituted with an alkyl group or a sulfonic acid group can be preferably used as the electron transporting material. In addition, the distyrylpyrazine derivative exemplified as the material of the light emitting layer can also be used as an electron transport material, and an inorganic semiconductor such as n-type-Si, n-type-SiC, etc. as in the case of the hole injection layer and the hole transport layer. Can also be used as an electron transporting material.

  In the present invention, the cyclic oligonaphthalene compound is particularly preferably used as an electron transport material.

  The electron transport layer can be formed by thinning the electron transport material by a known method such as a vacuum deposition method, a spin coating method, a casting method, a printing method including an ink jet method, or an LB method.

  Although there is no restriction | limiting in particular about the film thickness of an electron carrying layer, Usually, 5 nm-about 5 micrometers, Preferably it is 5-200 nm. The electron transport layer may have a single layer structure composed of one or more of the above materials.

  Further, an electron transport layer having a high n property doped with impurities can also be used. Examples thereof include JP-A-4-297076, JP-A-10-270172, JP-A-2000-196140, 2001-102175, J.A. Appl. Phys. 95, 5773 (2004), and the like.

  In the present invention, it is preferable to use an electron transport layer having such a high n property because an element with lower power consumption can be manufactured.

  The electron transport layer preferably contains a donor material. An example of the donor material is a p-type semiconductor material. Examples of p-type semiconductor materials include inorganic materials such as alkali metals, alkaline earth metals, rare earth elements, Al, Ag, Cu, and In, organic and inorganic alkali metal salts, alkaline earth metal salts, and aniline, phenylenediamine, Examples include arylamines such as N, N′-di (naphthalen-1-yl) -N, N′-diphenyl-benzidine, various condensed polycyclic aromatic compounds, and conjugated compounds.

  As the condensed polycyclic aromatic compound, for example, anthracene, tetracene, pentacene, hexacene, heptacene, chrysene, picene, fluorene, pyrene, peropyrene, perylene, terylene, quaterylene, coronene, ovalene, sarkham anthracene, bisanthene, zestrene, heptazelene, Examples thereof include compounds such as pyranthrene, violanthene, isoviolanthene, cacobiphenyl, anthradithiophene, and derivatives and precursors thereof.

  Examples of the conjugated compound include polythiophene and its oligomer, polypyrrole and its oligomer, polyaniline, polyphenylene and its oligomer, polyphenylene vinylene and its oligomer, polythienylene vinylene and its oligomer, polyacetylene, polydiacetylene, tetrathiafulvalene compound, quinone Compounds, cyano compounds such as tetracyanoquinodimethane, fullerenes and derivatives or mixtures thereof.

  In particular, among polythiophene and oligomers thereof, thiophene hexamer, α-seccithiophene α, ω-dihexyl-α-sexualthiophene, α, ω-dihexyl-α-kinkethiophene, α, ω-bis (3- An oligomer such as butoxypropyl) -α-sexithiophene can be preferably used.

  Other examples of polymer p-type semiconductors include polyacetylene, polyparaphenylene, polypyrrole, polyparaphenylene sulfide, polythiophene, polyphenylene vinylene, polycarbazole, polyisothianaphthene, polyheptadiyne, polyquinoline, polyaniline, and the like. JP-A-2006-36755, etc., substituted-unsubstituted alternating copolymer polythiophene, JP-A-2007-51289, JP-A-2005-76030, J. Pat. Amer. Chem. Soc. , 2007, p4112, J.A. Amer. Chem. Soc. , 2007, p7246, etc., polymers having a condensed ring thiophene structure, WO2008 / 000664, Adv. Mater. , 2007, p4160, Macromolecules, 2007, Vol. Examples thereof include thiophene copolymers such as 40 and p1981.

  Furthermore, porphyrin, copper phthalocyanine, tetrathiafulvalene (TTF) -tetracyanoquinodimethane (TCNQ) complex, bisethylenetetrathiafulvalene (BEDTTTTF) -perchloric acid complex, BEDTTTF-iodine complex, TCNQ-iodine complex, etc. Organic molecular complexes, fullerenes such as C60, C70, C76, C78 and C84, carbon nanotubes such as SWNT, dyes such as merocyanine dyes and hemicyanine dyes, σ-conjugated polymers such as polysilane and polygerman, and Organic / inorganic hybrid materials described in 2000-260999 can also be used.

  Among these π-conjugated materials, at least one selected from the group consisting of condensed polycyclic aromatic compounds such as pentacene, fullerenes, condensed ring tetracarboxylic acid diimides, metal phthalocyanines, and metal porphyrins is preferable. Further, pentacenes are more preferable.

  Examples of pentacenes include substituents described in International Publication No. 03/16599, International Publication No. 03/28125, US Pat. No. 6,690,029, Japanese Patent Application Laid-Open No. 2004-107216, and the like. A pentacene derivative described in U.S. Patent Application Publication No. 2003/136964 and the like; Amer. Chem. Soc. , Vol127. Examples thereof include substituted acenes described in No. 14.4986 and the like and derivatives thereof.

  Among these compounds, compounds that have high solubility in organic solvents to the extent that solution processing is possible, can form a crystalline thin film after drying, and can achieve high mobility are preferable. Such compounds include those described in J. Org. Amer. Chem. Soc. , Vol. 123, p9482; Amer. Chem. Soc. , Vol. 130 (2008), no. No. 9, 2706 and the like, acene-based compounds substituted with a trialkylsilylethynyl group, a pentacene precursor described in U.S. Patent Application Publication No. 2003/136964, etc., and Japanese Patent Application Laid-Open No. 2007-224019 Examples include precursor type compounds (precursors) such as porphyrin precursors.

"anode"
As the anode in the organic EL element, an electrode material made of a metal, an alloy, an electrically conductive compound, or a mixture thereof having a high work function (4 eV or more) is preferably used.

Specific examples of such electrode materials include metals such as Au, and conductive transparent materials such as CuI, indium tin oxide (ITO), SnO ₂ , and ZnO.

Alternatively, an amorphous material such as IDIXO (In ₂ O ₃ —ZnO) capable of forming a transparent conductive film may be used. For the anode, these electrode materials may be formed into a thin film by a method such as vapor deposition or sputtering, and a pattern having a desired shape may be formed by a photolithography method, or when pattern accuracy is not so high (about 100 μm or more) A pattern may be formed through a mask having a desired shape at the time of vapor deposition or sputtering of the electrode material. Or when using the substance which can be apply | coated like an organic electroconductivity compound, wet film-forming methods, such as a printing system and a coating system, can also be used.

  When light emission is extracted from the anode, it is desirable that the transmittance be greater than 10%, and the sheet resistance as the anode is preferably several hundred Ω / □ or less. Further, although the film thickness depends on the material, it is usually selected in the range of 10 to 1000 nm, preferably 10 to 200 nm.

"cathode"
On the other hand, as the cathode, a material having a low work function (4 eV or less) metal (referred to as an electron injecting metal), an alloy, an electrically conductive compound, and a mixture thereof as an electrode material is used. Specific examples of such electrode materials include sodium, sodium-potassium alloy, magnesium, lithium, magnesium / copper mixture, magnesium / silver mixture, magnesium / aluminum mixture, magnesium / indium mixture, aluminum / aluminum oxide (Al ₂ O ₃ ) Mixtures, indium, lithium / aluminum mixtures, rare earth metals and the like.

Among these, from the point of durability against electron injection and oxidation, etc., a mixture of an electron injecting metal and a second metal which is a stable metal having a larger work function than this, for example, a magnesium / silver mixture, Magnesium / aluminum mixtures, magnesium / indium mixtures, aluminum / aluminum oxide (Al ₂ O ₃ ) mixtures, lithium / aluminum mixtures, aluminum and the like are preferred. The cathode can be produced by forming a thin film of these electrode materials by a method such as vapor deposition or sputtering.

  The sheet resistance as the cathode is preferably several hundred Ω / □ or less, and the film thickness is usually selected in the range of 10 nm to 5 μm, preferably 50 to 200 nm. In order to transmit the emitted light, if either one of the anode or the cathode of the organic EL element is transparent or translucent, the light emission luminance is improved, which is convenient.

  Moreover, after producing the said metal by the film thickness of 1 nm-20 nm to a cathode, the transparent or semi-transparent cathode can be produced by producing the electroconductive transparent material quoted by description of the anode on it, By applying this, an element in which both the anode and the cathode are transmissive can be manufactured.

《Support substrate》
As a support substrate (hereinafter also referred to as a substrate, substrate, substrate, support, etc.) that can be used in the organic EL device of the present invention, there is no particular limitation on the type of glass, plastic, etc., and it is transparent. May be opaque. When extracting light from the support substrate side, the support substrate is preferably transparent.

  Examples of the transparent support substrate preferably used include glass, quartz, and a transparent resin film. A particularly preferable support substrate is a resin film capable of giving flexibility to the organic EL element.

  Examples of the resin film include polyesters such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyethylene, polypropylene, cellophane, cellulose diacetate, cellulose triacetate (TAC), cellulose acetate butyrate, cellulose acetate propionate ( CAP), cellulose esters such as cellulose acetate phthalate, cellulose nitrate or derivatives thereof, polyvinylidene chloride, polyvinyl alcohol, polyethylene vinyl alcohol, syndiotactic polystyrene, polycarbonate (PC), norbornene resin, polymethylpentene, polyether Ketone, polyimide, polyethersulfone (PES), polyphenylene sulfide, police Cycloolefins such as phons, polyether imides, polyether ketone imides, polyamides, fluororesins, nylons, polymethyl methacrylates, acrylics or polyarylates, Arton (trade name manufactured by JSR) or Apel (trade name manufactured by Mitsui Chemicals) Based resins and the like.

On the surface of the resin film, an inorganic film, an organic film, or a hybrid film of both may be formed. Water vapor permeability (25 ± 0.5 ° C.) measured by a method according to JIS K 7129-1992. , Relative humidity (90 ± 2)% RH) is preferably 0.01 g / (m ² · 24 h) or less, and further, oxygen measured by a method according to JIS K 7126-1987. A high barrier film having a permeability of 10 ⁻³ ml / (m ² · 24 h · MPa) or less and a water vapor permeability of 10 ⁻⁵ g / (m ² · 24 h) or less is preferable.

  As a material for forming the barrier film, any material may be used as long as it has a function of suppressing entry of elements that cause deterioration of elements such as moisture and oxygen. For example, silicon oxide, silicon dioxide, silicon nitride, or the like can be used. Further, in order to improve the brittleness of the film, it is more preferable to have a laminated structure of these inorganic layers and organic material layers.

  Although there is no restriction | limiting in particular about the lamination | stacking order of an inorganic layer and an organic layer, It is preferable to laminate | stack both alternately several times.

  The method for forming the barrier film is not particularly limited. For example, the vacuum deposition method, sputtering method, reactive sputtering method, molecular beam epitaxy method, cluster ion beam method, ion plating method, plasma polymerization method, atmospheric pressure plasma weight A combination method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, and the like can be used. However, an atmospheric pressure plasma polymerization method as described in JP-A-2004-68143 is particularly preferable.

  Examples of the opaque support substrate include metal plates such as aluminum and stainless steel, films, opaque resin substrates, and ceramic substrates.

  The external extraction efficiency at room temperature of light emission of the organic EL device of the present invention is preferably 1% or more, more preferably 5% or more.

  Here, the external extraction quantum efficiency (%) = the number of photons emitted to the outside of the organic EL element / the number of electrons sent to the organic EL element × 100.

  In addition, a hue improvement filter such as a color filter may be used in combination, or a color conversion filter that converts the emission color from the organic EL element into multiple colors using a phosphor. In the case of using a color conversion filter, the λmax of light emission of the organic EL element is preferably 480 nm or less.

<Sealing>
As a sealing means used for this invention, the method of adhere | attaching a sealing member, an electrode, and a support substrate with an adhesive agent can be mentioned, for example.

  As a sealing member, it should just be arrange | positioned so that the display area | region of an organic EL element may be covered, and concave plate shape or flat plate shape may be sufficient. Further, transparency and electrical insulation are not particularly limited.

  Specific examples include a glass plate, a polymer plate / film, and a metal plate / film. Examples of the glass plate include soda-lime glass, barium / strontium-containing glass, lead glass, aluminosilicate glass, borosilicate glass, barium borosilicate glass, and quartz. Examples of the polymer plate include polycarbonate, acrylic, polyethylene terephthalate, polyether sulfide, and polysulfone. Examples of the metal plate include those made of one or more metals or alloys selected from the group consisting of stainless steel, iron, copper, aluminum, magnesium, nickel, zinc, chromium, titanium, molybdenum, silicon, germanium, and tantalum.

In the present invention, a polymer film and a metal film can be preferably used because the element can be thinned. Furthermore, the polymer film has an oxygen permeability measured by a method according to JIS K 7126-1987 of 1 × 10 ⁻³ ml / (m ² · 24 h · MPa) or less, and a method according to JIS K 7129-1992. It is preferable that the water vapor permeability (25 ± 0.5 ° C., relative humidity (90 ± 2)% RH) measured in (1) is 1 × 10 ⁻³ g / (m ² · 24 h) or less.

  For processing the sealing member into a concave shape, sandblasting, chemical etching, or the like is used.

  Specific examples of the adhesive include photocuring and thermosetting adhesives having reactive vinyl groups such as acrylic acid oligomers and methacrylic acid oligomers, and moisture curing adhesives such as 2-cyanoacrylates. be able to.

  Moreover, heat | fever and chemical curing types (two-component mixing), such as an epoxy type, can be mentioned. Moreover, hot-melt type polyamide, polyester, and polyolefin can be mentioned. Moreover, a cationic curing type ultraviolet curing epoxy resin adhesive can be mentioned.

  In addition, since an organic EL element may deteriorate by heat processing, what can be adhesive-hardened from room temperature to 80 degreeC is preferable. A desiccant may be dispersed in the adhesive. Application | coating of the adhesive agent to a sealing part may use commercially available dispenser, and may print like screen printing.

  In addition, it is also preferable that the electrode and the organic layer are coated on the outside of the electrode facing the support substrate with the organic layer interposed therebetween, and an inorganic or organic layer is formed in contact with the support substrate to form a sealing film. . In this case, the material for forming the film may be any material that has a function of suppressing intrusion of elements that cause deterioration of elements such as moisture and oxygen. For example, silicon oxide, silicon dioxide, silicon nitride, or the like may be used. it can. Further, in order to improve the brittleness of the film, it is preferable to have a laminated structure of these inorganic layers and layers made of organic materials.

  The method for forming these films is not particularly limited. For example, vacuum deposition, sputtering, reactive sputtering, molecular beam epitaxy, cluster-ion beam method, ion plating method, plasma polymerization method, atmospheric pressure plasma A polymerization method, a plasma CVD method, a laser CVD method, a thermal CVD method, a coating method, or the like can be used.

  In the gap between the sealing member and the display area of the organic EL element, an inert gas such as nitrogen or argon, or an inert liquid such as fluorinated hydrocarbon or silicon oil can be injected in the gas phase and liquid phase. preferable. A vacuum is also possible. Moreover, a hygroscopic compound can also be enclosed inside.

  Examples of the hygroscopic compound include metal oxides (for example, sodium oxide, potassium oxide, calcium oxide, barium oxide, magnesium oxide, aluminum oxide) and sulfates (for example, sodium sulfate, calcium sulfate, magnesium sulfate, cobalt sulfate). Etc.), metal halides (eg calcium chloride, magnesium chloride, cesium fluoride, tantalum fluoride, cerium bromide, magnesium bromide, barium iodide, magnesium iodide etc.), perchloric acids (eg perchloric acid) Barium, magnesium perchlorate, and the like), and anhydrous salts are preferably used in sulfates, metal halides, and perchloric acids.

《Protective film, protective plate》
In order to increase the mechanical strength of the element, a protective film or a protective plate may be provided on the outer side of the sealing film on the side facing the support substrate with the organic layer interposed therebetween or on the sealing film.

  In particular, when the sealing is performed by the sealing film, the mechanical strength is not necessarily high, and thus it is preferable to provide such a protective film and a protective plate. As a material that can be used for this, the same glass plate, polymer plate / film, metal plate / film, etc. used for the sealing can be used, but the polymer film is light and thin. Is preferably used.

《Light extraction》
The organic EL element emits light inside a layer having a refractive index higher than that of air (refractive index is about 1.7 to 2.1) and can extract only about 15% to 20% of the light generated in the light emitting layer. It is generally said.

  This is because light incident on the interface (interface between the transparent substrate and air) at an angle θ greater than the critical angle causes total reflection and cannot be taken out of the device, or between the transparent electrode or light emitting layer and the transparent substrate. This is because the light is totally reflected between the light and the light is guided through the transparent electrode or the light emitting layer, and as a result, the light escapes in the direction of the element side surface.

  As a method for improving the light extraction efficiency, for example, a method of forming irregularities on the surface of the transparent substrate to prevent total reflection at the interface between the transparent substrate and the air (US Pat. No. 4,774,435), A method of improving efficiency by providing a light collecting property to a substrate (Japanese Patent Laid-Open No. 63-314795), a method of forming a reflective surface on a side surface of an element (Japanese Patent Laid-Open No. 1-220394), and light emission from a substrate A method of forming an antireflection film by introducing a flat layer having an intermediate refractive index between the bodies (Japanese Patent Laid-Open No. 62-172691), a flat having a lower refractive index between the substrate and the light emitter than the substrate A method of introducing a layer (Japanese Patent Laid-Open No. 2001-202827), a method of forming a diffraction grating between any one of a substrate, a transparent electrode layer and a light emitting layer (including between the substrate and the outside) (Japanese Patent Laid-Open No. 11-283951) Gazette).

  In the present invention, these methods can be used in combination with the organic EL device of the present invention. However, a method of introducing a flat layer having a lower refractive index than the substrate between the substrate and the light emitter, or a substrate, transparent A method of forming a diffraction grating between any layers of the electrode layer and the light emitting layer (including between the substrate and the outside) can be suitably used.

  In the present invention, by combining these means, it is possible to obtain an element having higher luminance or durability.

  When a medium having a low refractive index is formed between the transparent electrode and the transparent substrate with a thickness longer than the wavelength of light, the light extracted from the transparent electrode has a higher extraction efficiency to the outside as the refractive index of the medium is lower.

  Examples of the low refractive index layer include aerogel, porous silica, magnesium fluoride, and a fluorine-based polymer. Since the refractive index of the transparent substrate is generally about 1.5 to 1.7, the low refractive index layer preferably has a refractive index of about 1.5 or less. Further, it is preferably 1.35 or less.

  The thickness of the low refractive index medium is preferably at least twice the wavelength in the medium. This is because the effect of the low refractive index layer is diminished when the thickness of the low refractive index medium is about the wavelength of light and the electromagnetic wave that has exuded by evanescent enters the substrate.

  The method of introducing a diffraction grating into an interface or any medium that causes total reflection is characterized by a high effect of improving light extraction efficiency.

  This method uses the property that the diffraction grating can change the direction of light to a specific direction different from refraction by so-called Bragg diffraction such as first-order diffraction and second-order diffraction. Light that cannot be emitted due to total internal reflection between layers is diffracted by introducing a diffraction grating in any layer or medium (in a transparent substrate or transparent electrode), and the light is removed. I want to take it out.

  The introduced diffraction grating desirably has a two-dimensional periodic refractive index. This is because light emitted from the light-emitting layer is randomly generated in all directions, so in a general one-dimensional diffraction grating having a periodic refractive index distribution only in a certain direction, only light traveling in a specific direction is diffracted. Therefore, the light extraction efficiency does not increase so much.

  However, by making the refractive index distribution a two-dimensional distribution, light traveling in all directions is diffracted, and light extraction efficiency is increased.

  As described above, the position where the diffraction grating is introduced may be in any of the layers or in the medium (in the transparent substrate or in the transparent electrode), but is preferably in the vicinity of the organic light emitting layer where light is generated.

  At this time, the period of the diffraction grating is preferably about 1/2 to 3 times the wavelength of light in the medium.

  The arrangement of the diffraction grating is preferably two-dimensionally repeated, such as a square lattice, a triangular lattice, or a honeycomb lattice.

<Condenser sheet>
The organic EL device of the present invention can be processed to provide, for example, a microlens array-like structure on the light extraction side of the substrate, or combined with a so-called condensing sheet, for example, in a specific direction, for example, the device light emitting surface. On the other hand, the brightness | luminance in a specific direction can be raised by condensing in a front direction.

  As an example of the microlens array, quadrangular pyramids having a side of 30 μm and an apex angle of 90 degrees are two-dimensionally arranged on the light extraction side of the substrate. One side is preferably 10 to 100 μm. If it becomes smaller than this, the effect of diffraction will generate | occur | produce and color, and if too large, thickness will become thick and is not preferable.

  As the condensing sheet, for example, a sheet that is put into practical use in an LED backlight of a liquid crystal display device can be used. As such a sheet, for example, a brightness enhancement film (BEF) manufactured by Sumitomo 3M Limited can be used. As the shape of the prism sheet, for example, the base material may be formed by forming a △ -shaped stripe having a vertex angle of 90 degrees and a pitch of 50 μm, or the vertex angle is rounded and the pitch is changed randomly. Other shapes may be used.

  Moreover, in order to control the light emission angle from a light emitting element, you may use together a light diffusing plate and a film with a condensing sheet. For example, a diffusion film (light-up) manufactured by Kimoto Co., Ltd. can be used.

<< Method for Manufacturing Organic EL Element >>
As an example of a method for producing an organic EL element, a method for producing an element comprising an anode / hole injection layer / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / cathode will be described.

  First, a desired electrode material, for example, a thin film made of an anode material is formed on a suitable substrate so as to have a thickness of 1 μm or less, preferably 10 to 200 nm, and an anode is manufactured.

  Next, a thin film containing an organic compound such as a hole injection layer, a hole transport layer, a light emitting layer, a hole blocking layer, and an electron transport layer, which is an organic EL element material, is formed thereon.

  As a method for forming each of these layers, there are a vapor deposition method, a wet method (coating method, wet process), etc., but a wet method is preferable. Examples of wet methods include spin coating, casting, die coating, blade coating, roll coating, ink jet, printing, spray coating, curtain coating, etc., and a precise thin film can be formed. From the viewpoint of high productivity, a method having high suitability for a roll-to-roll method such as a die coating method, a roll coating method, an ink jet method, and a spray coating method is preferable. Different film forming methods may be applied for each layer.

  In particular, the layer containing the cyclic oligonaphthalene compound represented by the general formula (1) according to the present invention is preferably formed by the above coating method, and the layer is preferably a light emitting layer.

  Further, when the total number of layers (the constituent layers of the organic EL element) existing between the anode and the cathode is 100%, 50% or more of the total number of layers is preferably formed by a coating method. .

  For example, in the anode / hole injection layer / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / electron injection layer / cathode mentioned as an example of the organic EL element, the hole injection layer In the case where the total number of layers / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / electron injection layer is 6, it is preferable that at least three layers are formed by a coating method.

  When the constituent layers of the organic EL device of the present invention are formed by coating, examples of the liquid medium for dissolving or dispersing various organic EL materials used for coating include ketones such as methyl ethyl ketone and cyclohexanone, and fatty acid esters such as ethyl acetate. , Halogenated hydrocarbons such as dichlorobenzene, aromatic hydrocarbons such as toluene, xylene, mesitylene and cyclohexylbenzene, aliphatic hydrocarbons such as cyclohexane, decalin and dodecane, and organic solvents such as DMF and DMSO be able to.

  Moreover, as a dispersion method, it can disperse | distribute by dispersion methods, such as an ultrasonic wave, high shear force dispersion | distribution, and media dispersion | distribution.

  After these layers are formed, a thin film made of a cathode material is formed thereon by a method such as vapor deposition or sputtering so as to have a thickness of 1 μm or less, preferably in the range of 50 to 200 nm. By providing, a desired organic EL element can be obtained.

  Further, it is also possible to reverse the production order and produce the cathode, the electron injection layer, the electron transport layer, the hole blocking layer, the light emitting layer, the hole transport layer, the hole injection layer, and the anode in this order.

  The organic EL device of the present invention is preferably produced from the hole injection layer to the cathode consistently by a single evacuation, but may be taken out halfway and subjected to different film forming methods. At that time, it is necessary to consider that the work is performed in a dry inert gas atmosphere.

<Application>
The organic EL element of the present invention can be used as a display device, a display, and various light emission sources. For example, lighting devices (home lighting, interior lighting), clock and liquid crystal backlights, billboard advertisements, traffic lights, light sources of optical storage media, light sources of electrophotographic copying machines, light sources of optical communication processors, light Although the light source of a sensor etc. are mentioned, It is not limited to this, Especially, it can use effectively for the use as a backlight of a liquid crystal display device, and a light source for illumination.

  In the organic EL element of the present invention, patterning may be performed by a metal mask, an ink jet printing method, or the like as needed during film formation.

  In the case of patterning, only the electrode may be patterned, the electrode and the light emitting layer may be patterned, or the entire layer of the element may be patterned. In the fabrication of the element, a conventionally known method is used. Can do.

  The light emission color of the organic EL device of the present invention and the compound according to the present invention is shown in FIG. 4.16 on page 108 of “New Color Science Handbook” (edited by the Japan Color Society, University of Tokyo Press, 1985). It is determined by the color when the result measured with the total CS-1000 (manufactured by Konica Minolta Sensing) is applied to the CIE chromaticity coordinates.

When the organic EL element of the present invention is a white element, white means that the chromaticity in the CIE1931 color system at 1000 cd / m ² is X when the 2 ° viewing angle front luminance is measured by the above method. = 0.33 ± 0.07 and Y = 0.33 ± 0.1.

<Display device>
The display device of the present invention will be described. The display device of the present invention comprises the organic EL element of the present invention.

  Although the display device of the present invention may be single color or multicolor, the multicolor display device will be described here. In the case of a multicolor display device, a shadow mask is provided only at the time of forming a light emitting layer, and a film can be formed on one surface by vapor deposition, casting, spin coating, ink jet, printing, or the like.

  In the case of patterning only the light emitting layer, the method is not limited. However, the vapor deposition method, the ink jet method, the spin coating method, and the printing method are preferable.

  The configuration of the organic EL element provided in the display device is selected from the above-described configuration examples of the organic EL element as necessary.

  Moreover, the manufacturing method of an organic EL element is as having shown to the one aspect | mode of manufacture of the organic EL element of said invention.

  When a DC voltage is applied to the obtained multicolor display device, light emission can be observed by applying a voltage of about 2 to 40 V with the positive polarity of the anode and the negative polarity of the cathode. Further, even when a voltage is applied with the opposite polarity, no current flows and no light emission occurs. Further, when an AC voltage is applied, light is emitted only when the anode is in the + state and the cathode is in the-state. The alternating current waveform to be applied may be arbitrary.

  The multicolor display device can be used as a display device, a display, and various light emission sources. In a display device or display, full-color display is possible by using three types of organic EL elements of blue, red, and green light emission.

  Examples of the display device and display include a television, a personal computer, a mobile device, an AV device, a character broadcast display, and an information display in an automobile. In particular, it may be used as a display device for reproducing still images and moving images, and the driving method when used as a display device for reproducing moving images may be either a simple matrix (passive matrix) method or an active matrix method.

  Light sources include home lighting, interior lighting, clock and liquid crystal backlights, billboard advertisements, traffic lights, light sources for optical storage media, light sources for electrophotographic copying machines, light sources for optical communication processors, light sources for optical sensors, etc. The present invention is not limited to these examples.

  Hereinafter, an example of a display device having the organic EL element of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic view showing an example of a display device composed of organic EL elements. It is a schematic diagram of a display such as a mobile phone that displays image information by light emission of an organic EL element.

  The display 1 includes a display unit A having a plurality of pixels, a control unit B that performs image scanning of the display unit A based on image information, and the like.

  The control unit B is electrically connected to the display unit A, and sends a scanning signal and an image data signal to each of a plurality of pixels based on image information from the outside, and the pixels for each scanning line respond to the image data signal by the scanning signal. The image information is sequentially emitted to scan the image and display the image information on the display unit A.

  FIG. 2 is a schematic diagram of the display unit A.

  The display unit A includes a wiring unit including a plurality of scanning lines 5 and data lines 6, a plurality of pixels 3 and the like on a substrate. The main members of the display unit A will be described below.

  In the figure, the light emitted from the pixel 3 is extracted in the direction of the white arrow (downward).

  The scanning line 5 and the plurality of data lines 6 in the wiring portion are each made of a conductive material, and the scanning lines 5 and the data lines 6 are orthogonal to each other in a grid pattern and are connected to the pixels 3 at the orthogonal positions (details are illustrated). Not) When a scanning signal is applied from the scanning line 5, the pixel 3 receives an image data signal from the data line 6 and emits light according to the received image data.

  Full-color display is possible by appropriately arranging pixels in the red region, the green region, and the blue region on the same substrate.

  Next, the light emission process of the pixel will be described.

  FIG. 3 is a schematic diagram of a pixel.

  The pixel includes an organic EL element 10, a switching transistor 11, a driving transistor 12, a capacitor 13, and the like. A full color display can be performed by using red, green, and blue light emitting organic EL elements as the organic EL elements 10 in a plurality of pixels, and juxtaposing them on the same substrate.

  In FIG. 3, an image data signal is applied from the control unit B to the drain of the switching transistor 11 through the data line 6. When a scanning signal is applied from the control unit B to the gate of the switching transistor 11 via the scanning line 5, the driving of the switching transistor 11 is turned on, and the image data signal applied to the drain is supplied to the capacitor 13 and the driving transistor 12. Is transmitted to the gate.

  By transmitting the image data signal, the capacitor 13 is charged according to the potential of the image data signal, and the drive of the drive transistor 12 is turned on. The drive transistor 12 has a drain connected to the power supply line 7 and a source connected to the electrode of the organic EL element 10, and the power supply line 7 connects to the organic EL element 10 according to the potential of the image data signal applied to the gate. Current is supplied.

  When the scanning signal is moved to the next scanning line 5 by the sequential scanning of the control unit B, the driving of the switching transistor 11 is turned off. However, even if the driving of the switching transistor 11 is turned off, the capacitor 13 maintains the potential of the charged image data signal, so that the driving of the driving transistor 12 is kept on and the next scanning signal is applied. Until then, the light emission of the organic EL element 10 continues. When the scanning signal is next applied by sequential scanning, the driving transistor 12 is driven according to the potential of the next image data signal synchronized with the scanning signal, and the organic EL element 10 emits light.

  That is, the light emission of the organic EL element 10 is performed by providing the switching transistor 11 and the drive transistor 12 which are active elements with respect to the organic EL element 10 of each of the plurality of pixels. It is carried out. Such a light emitting method is called an active matrix method.

  Here, the light emission of the organic EL element 10 may be light emission of a plurality of gradations by a multi-value image data signal having a plurality of gradation potentials, or by turning on / off a predetermined light emission amount by a binary image data signal. Good. The potential of the capacitor 13 may be held continuously until the next scanning signal is applied, or may be discharged immediately before the next scanning signal is applied.

  In the present invention, not only the active matrix method described above, but also a passive matrix light emission drive in which the organic EL element emits light according to the data signal only when the scanning signal is scanned.

  FIG. 4 is a schematic diagram of a passive matrix display device. In FIG. 4, a plurality of scanning lines 5 and a plurality of image data lines 6 are provided in a lattice shape so as to face each other with the pixel 3 interposed therebetween.

  When the scanning signal of the scanning line 5 is applied by sequential scanning, the pixels 3 connected to the applied scanning line 5 emit light according to the image data signal.

  In the passive matrix system, the pixel 3 has no active element, and the manufacturing cost can be reduced.

  FIG. 7 is a schematic configuration diagram of an organic EL full-color display device. After patterning the substrate on which the ITO transparent electrode 102 is formed on the glass substrate 101 as an anode, a partition wall 103 is formed between the ITO transparent electrodes on the glass substrate. A hole injection layer composition is injected between the ITO electrode partition walls, and a hole injection layer 104 is produced by a drying process. A blue light emitting layer composition, a green light emitting layer composition, and a red color are formed on the hole injection layer, respectively. The light emitting layer composition is injected to form each light emitting layer 105B, light emitting layer 105G, and light emitting layer 105R. Finally, a cathode is vacuum-deposited so as to cover the light emitting layers 105B, 105G, and 105R, and an organic EL element is manufactured.

《Lighting device》
The lighting device of the present invention will be described. The illuminating device of this invention has the said organic EL element.

  The organic EL element of the present invention may be used as an organic EL element having a resonator structure. The purpose of use of the organic EL element having such a resonator structure is as follows. The light source of a machine, the light source of an optical communication processing machine, the light source of a photosensor, etc. are mentioned, However, It is not limited to these. Moreover, you may use for the said use by making a laser oscillation.

  The organic EL element of the present invention may be used as a kind of lamp for illumination or exposure light source, a projection device for projecting an image, or a display for directly viewing a still image or a moving image. It may be used as a device (display).

  The driving method when used as a display device for moving image reproduction may be either a simple matrix (passive matrix) method or an active matrix method. Alternatively, a full-color display device can be manufactured by using two or more organic EL elements of the present invention having different emission colors. The organic EL material of the present invention can be applied as an illumination device to an organic EL element that emits substantially white light. A plurality of light emitting colors are simultaneously emitted by a plurality of light emitting materials to obtain white light emission by color mixing. The combination of a plurality of emission colors may include three emission maximum wavelengths of the three primary colors of blue, green, and blue, or two using the relationship of complementary colors such as blue and yellow, blue green and orange, etc. The thing containing the light emission maximum wavelength may be used.

  In addition, a combination of light emitting materials for obtaining a plurality of emission colors is a combination of a plurality of phosphorescent or fluorescent materials, a light emitting material that emits fluorescence or phosphorescence, and light from the light emitting material as excitation light. Any of those combined with a dye material that emits light may be used, but in the white organic EL device according to the present invention, only a combination of a plurality of light-emitting dopants may be mixed.

  It is only necessary to provide a mask only when forming a light emitting layer, a hole transport layer, an electron transport layer, etc., and simply arrange them separately by coating with the mask. In addition, for example, an electrode film can be formed by a vapor deposition method, a cast method, a spin coating method, an ink jet method, a printing method, or the like, and productivity is also improved.

  According to this method, unlike a white organic EL device in which light emitting elements of a plurality of colors are arranged in parallel in an array, the elements themselves are luminescent white.

  There is no restriction | limiting in particular as a luminescent material used for a light emitting layer, For example, if it is a backlight in a liquid crystal display element, the metal complex which concerns on this invention so that it may suit the wavelength range corresponding to CF (color filter) characteristic, Any one of known luminescent materials may be selected and combined to whiten.

<< One Embodiment of Lighting Device of the Present Invention >>
One aspect of the lighting device of the present invention that includes the organic EL element of the present invention will be described.

  The non-light emitting surface of the organic EL device of the present invention is covered with a glass case, a glass substrate having a thickness of 300 μm is used as a sealing substrate, and an epoxy-based photocurable adhesive (LUX TRACK manufactured by Toagosei Co., Ltd.) is used as a sealing material. LC0629B) is applied, and this is overlaid on the cathode and brought into close contact with the transparent support substrate, irradiated with UV light from the glass substrate side, cured and sealed, and an illumination device as shown in FIGS. Can be formed.

  FIG. 5 shows a schematic view of the lighting device, and the organic EL element 201 of the present invention is covered with a glass cover 202 (in addition, the sealing operation with the glass cover is to bring the organic EL element 201 into contact with the atmosphere. And a glove box under a nitrogen atmosphere (in an atmosphere of high-purity nitrogen gas having a purity of 99.999% or more).

  6 shows a cross-sectional view of the lighting device. In FIG. 6, reference numeral 205 denotes a cathode, 206 denotes an organic EL layer, and 207 denotes a glass substrate with a transparent electrode. The glass cover 202 is filled with nitrogen gas 208 and a water catching agent 209 is provided.

  EXAMPLES Hereinafter, the present invention will be specifically described with reference to examples, but the present invention is not limited thereto. In addition, although the display of "part" or "%" is used in an Example, unless otherwise indicated, "part by mass" or "mass%" is represented.

Example 1
<< Production of organic EL element >>
(Preparation of organic EL element 1-1)
After patterning on a substrate (NH-Techno Glass NA-45) formed by depositing 100 nm of ITO (indium tin oxide) on a 100 mm × 100 mm × 1.1 mm glass substrate as an anode, this ITO transparent electrode was provided. The transparent support substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes. On this transparent support substrate, a solution obtained by diluting poly (3,4-ethylenedioxythiophene) -polystyrene sulfonate (PEDOT / PSS, Bayer, Baytron P Al 4083) to 70% with pure water at 3000 rpm for 30 seconds. Then, the film was formed by spin coating and then dried at 200 ° C. for 1 hour to provide a first hole transport layer having a thickness of 30 nm.

The substrate provided with the first hole transport layer is fixed to a substrate holder of a commercially available vacuum deposition apparatus, each organic EL material described later is set on a resistance heating boat made of molybdenum or tantalum, and the vacuum chamber is set to 4 ×. The pressure was reduced to 10 ⁻⁴ Pa. The heating boat containing C-2 was energized and heated, and deposited at a deposition rate of 0.1 nm / second to provide a 20 nm second hole transport layer.

  Next, the heating boat containing OC-5 and D-15 is energized and heated, and co-deposited on the second hole transport layer at a deposition rate of 0.1 nm / second and 0.006 nm / second, respectively. A 40 nm light emitting layer was provided.

Furthermore, (2-methyl-8-quinolinato) (p-phenylphenolate) aluminum (BAlq) was vapor-deposited on the light emitting layer at a vapor deposition rate of 0.1 nm / second to form a first electron transport layer having a thickness of 10 nm, (8-quinolinato) A second electron transport having a film thickness of 30 nm is formed by energizing and heating the heating boat containing aluminum (Alq ₃ ), and depositing on the first electron transport layer at a deposition rate of 0.1 nm / second. A layer was provided.

  Then, 0.5 nm of lithium fluoride was vapor-deposited as a cathode buffer layer, and also aluminum 110nm was vapor-deposited, the cathode was formed, and the organic EL element 1-1 was produced. In addition, the substrate temperature at the time of vapor deposition was room temperature.

(Production of organic EL elements 1-2 to 1-19)
In the production of the organic EL element 1-1, organic EL elements 1-2 to 1-19 were produced in the same manner except that the materials constituting each organic layer were changed to the materials shown in Tables 1 to 3.

  Evaluation of the obtained organic EL element is described after Example 5 together with evaluation of the organic EL element of Examples 2-5.

Example 2
After patterning on a substrate (NH-Techno Glass NA-45) formed by depositing 100 nm of ITO (indium tin oxide) on a 100 mm × 100 mm × 1.1 mm glass substrate as an anode, this ITO transparent electrode was provided. The transparent support substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes. On this transparent support substrate, a solution obtained by diluting poly (3,4-ethylenedioxythiophene) -polystyrene sulfonate (PEDOT / PSS, Bayer, Baytron P Al 4083) to 70% with pure water at 3000 rpm for 30 seconds. Then, the film was formed by spin coating and then dried at 200 ° C. for 1 hour to provide a first hole transport layer having a thickness of 30 nm.

The substrate provided with the first hole transport layer is fixed to a substrate holder of a commercially available vacuum deposition apparatus, each organic EL material described later is set on a resistance heating boat made of molybdenum or tantalum, and the vacuum chamber is set to 4 ×. The pressure was reduced to 10 ⁻⁴ Pa. The heating boat containing C-2 and vanadium oxide was energized and heated, and co-deposited on the first hole transport layer at a deposition rate of 0.1 nm / second and 0.003 nm / second, respectively, to form a 20 nm first layer. A two-hole transport layer was provided.

  Next, the heating boat containing OC-5 and D-15 is energized and heated, and co-deposited on the second hole transport layer at a deposition rate of 0.1 nm / second and 0.006 nm / second, respectively. A 40 nm light emitting layer was provided.

  Furthermore, OC-17 was vapor-deposited on the light emitting layer at a vapor deposition rate of 0.1 nm / second, heated by energizing the heating boat containing the first electron transport layer having a thickness of 10 nm and OC-103, and the vapor deposition rate. A second electron transport layer having a thickness of 30 nm was provided by vapor deposition on the first electron transport layer at 0.1 nm / second. Subsequently, 2.0 nm of cesium fluoride was deposited as a cathode buffer layer, and 110 nm of aluminum was further deposited to form a cathode, thereby fabricating an organic EL element 2-1. In addition, the substrate temperature at the time of vapor deposition was room temperature.

(Preparation of organic EL elements 2-2 to 2-5)
In the production of the organic EL element 2-1, organic EL elements 2-2 to 2-5 were similarly produced except that the material constituting each organic layer was changed to the material shown in Table 4.

Example 3
After patterning on a substrate (NH-Techno Glass NA-45) formed by depositing 100 nm of ITO (indium tin oxide) on a 100 mm × 100 mm × 1.1 mm glass substrate as an anode, this ITO transparent electrode was provided. The transparent support substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes. On this transparent support substrate, a solution obtained by diluting poly (3,4-ethylenedioxythiophene) -polystyrene sulfonate (PEDOT / PSS, Bayer, Baytron P Al 4083) to 70% with pure water at 3000 rpm for 30 seconds. Then, the film was formed by spin coating and then dried at 200 ° C. for 1 hour to provide a first hole transport layer having a thickness of 30 nm.

The substrate provided with the first hole transport layer is fixed to a substrate holder of a commercially available vacuum deposition apparatus, each organic EL material described later is set on a resistance heating boat made of molybdenum or tantalum, and the vacuum chamber is set to 4 ×. The pressure was reduced to 10 ⁻⁴ Pa. The heating boat containing D-1 was energized and heated, and deposited at a deposition rate of 0.1 nm / second to provide a 20 nm second hole transport layer.

  Next, the heating boat containing OC-5 and D-15 is energized and heated, and co-deposited on the second hole transport layer at a deposition rate of 0.1 nm / second and 0.006 nm / second, respectively. A 40 nm light emitting layer was provided.

  Further, BAlq was vapor-deposited on the light emitting layer at a vapor deposition rate of 0.1 nm / second, heated by energizing the heating boat containing the first electron transport layer having a thickness of 10 nm and C-2. A second electron transport layer having a thickness of 30 nm was formed by vapor deposition on the first electron transport layer at 1 nm / second.

  Subsequently, 2.0 nm of cesium fluoride was vapor-deposited as a cathode buffer layer, and further, 110 nm of aluminum was vapor-deposited to form a cathode, thereby producing an organic EL element 3-1. In addition, the substrate temperature at the time of vapor deposition was room temperature.

(Production of organic EL elements 3-2 to 3-15)
In the production of the organic EL element 3-1, organic EL elements 3-2 to 3-15 were similarly produced except that the materials constituting each organic layer were changed to the materials shown in Tables 5 to 7.

Example 4
After patterning on a substrate (NH-Techno Glass NA-45) formed by depositing 100 nm of ITO (indium tin oxide) on a 100 mm × 100 mm × 1.1 mm glass substrate as an anode, this ITO transparent electrode was provided. The transparent support substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes. On this transparent support substrate, a solution obtained by diluting poly (3,4-ethylenedioxythiophene) -polystyrene sulfonate (PEDOT / PSS, Bayer, Baytron P Al 4083) to 70% with pure water at 3000 rpm for 30 seconds. Then, the film was formed by spin coating and then dried at 200 ° C. for 1 hour to provide a first hole transport layer having a thickness of 30 nm.

The substrate provided with the first hole transport layer is fixed to a substrate holder of a commercially available vacuum deposition apparatus, each organic EL material described later is set on a resistance heating boat made of molybdenum or tantalum, and the vacuum chamber is set to 4 ×. The pressure was reduced to 10 ⁻⁴ Pa. The heating boat containing OC-1 was energized and heated, and deposited at a deposition rate of 0.1 nm / second to provide a 20 nm second hole transport layer.

  Next, the heating boat containing OC-5 and D-15 is energized and heated, and co-deposited on the second hole transport layer at a deposition rate of 0.1 nm / second and 0.006 nm / second, respectively. A 40 nm light emitting layer was provided.

  Furthermore, BAlq is vapor-deposited on the light emitting layer at a vapor deposition rate of 0.1 nm / second and heated by energizing the heating boat containing the first electron transport layer having a thickness of 10 nm, C-2, and cesium fluoride, A 30-nm second electron transport layer was provided by co-deposition on the first electron-transport layer at a deposition rate of 0.1 nm / second and 0.002 nm / second, respectively.

  Then, 0.5 nm of lithium fluoride was vapor-deposited as a cathode buffer layer, and also aluminum 110nm was vapor-deposited, the cathode was formed, and the organic EL element 3-1 was produced. In addition, the substrate temperature at the time of vapor deposition was room temperature.

(Production of organic EL elements 4-2 to 4-7)
In the production of the organic EL element 4-1, organic EL elements 4-2 to 4-7 were similarly produced except that the material constituting each organic layer was changed to the material shown in Table 8.

Example 5
After patterning on a substrate (NH-Techno Glass NA-45) formed by depositing 100 nm of ITO (indium tin oxide) on a 100 mm × 100 mm × 1.1 mm glass substrate as an anode, this ITO transparent electrode was provided. The transparent support substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes. On this transparent support substrate, a solution obtained by diluting poly (3,4-ethylenedioxythiophene) -polystyrene sulfonate (PEDOT / PSS, Bayer, Baytron P Al 4083) to 70% with pure water at 3000 rpm for 30 seconds. Then, the film was formed by spin coating and then dried at 200 ° C. for 1 hour to provide a first hole transport layer having a thickness of 30 nm.

The substrate provided with the first hole transport layer is fixed to a substrate holder of a commercially available vacuum deposition apparatus, each organic EL material described later is set on a resistance heating boat made of molybdenum or tantalum, and the vacuum chamber is set to 4 ×. The pressure was reduced to 10 ⁻⁴ Pa. The heating boat containing OC-1 was energized and heated, and deposited at a deposition rate of 0.1 nm / second to provide a 20 nm second hole transport layer.

  Subsequently, the heating boat containing C-2 and D-21 is energized and heated, and co-deposited on the second hole transport layer at a deposition rate of 0.1 nm / second and 0.003 nm / second, respectively. A 40 nm light emitting layer was provided.

  Further, BAlq was vapor-deposited on the light emitting layer at a vapor deposition rate of 0.1 nm / second, heated by energizing the heating boat containing the first electron transport layer having a thickness of 10 nm and OC-45. A second electron transport layer having a thickness of 30 nm was formed by vapor deposition on the first electron transport layer at 1 nm / second.

  Then, 0.5 nm of lithium fluoride was vapor-deposited as a cathode buffer layer, and also aluminum 110nm was vapor-deposited, the cathode was formed, and the organic EL element 5-1 was produced.

  In addition, the substrate temperature at the time of vapor deposition was room temperature.

(Production of organic EL elements 5-2 to 5-6)
In the production of the organic EL element 5-1, organic EL elements 5-2 to 5-6 were similarly produced except that the material constituting each organic layer was changed to the material shown in Table 9.

<< Evaluation of organic EL elements >>
When evaluating the obtained organic EL device, the non-light-emitting surface of each organic EL device after production was covered with a glass case, a glass substrate having a thickness of 300 μm was used as a sealing substrate, and an epoxy was used as a sealing material around. A photo-curing adhesive (Lux Track LC0629B manufactured by Toagosei Co., Ltd.) is applied, and this is stacked on the cathode and brought into intimate contact with the transparent support substrate. The glass substrate is irradiated with UV light, cured, and sealed. The lighting device as shown in FIGS. 3 and 4 was formed and evaluated.

(External quantum efficiency)
About the produced organic EL element, external extraction quantum efficiency (%) when ^2.5 mA / cm ² constant current was applied in a dry nitrogen gas atmosphere at 23 ° C. was measured. For the measurement, a spectral radiance meter CS-1000 (manufactured by Konica Minolta Sensing) was used. The external extraction quantum efficiencies are obtained when the external extraction quantum efficiencies of the comparative examples for each table (the comparative example is 1-18 for a plurality of tables 3, 4-6 for table 8, and 5-4 for table 9) are 100. Shown as a relative value.

(Drive voltage)
The voltage at the start of light emission was measured at a temperature of 23 ° C. in a dry nitrogen gas atmosphere. Note that the voltage value at the start of light emission was measured when the luminance was 50 cd / m ² or more. A spectral radiance meter CS-1000 (manufactured by Konica Minolta Sensing) was used for measuring the luminance. In addition, when the voltage value (DV ₇₀ ) is 30% lower than the initial luminance and the voltage value (DV ₅₀ ) is 50% lower (halved) from the initial luminance under the light emission lifetime measurement conditions described later, DV ₇₀ ) − (DV ₀ ) was Δ1, and (DV ₅₀ ) − (DV ₀ ) was Δ2, which was used as an indicator of changes in drive voltage over time. Δ1 is shown as a relative value for each table when Δ1 is set to 100 in a comparative example (the comparative example is 1-18 for a plurality of tables 3, 4-6 for table 8, and 5-4 for table 9). Δ2 is shown as a relative value for each table when Δ1 is set to 100 in a comparative example (the comparative example is 1-18 for a plurality of tables 3, 4-6 for table 8, and 5-4 for table 9).

(Luminescent life)
When driving at a constant current of ^2.5 mA / cm ^{2 in} a dry nitrogen gas atmosphere at 23 ° C., the time required for the luminance to drop to half of the luminance immediately after the start of light emission (initial luminance) was measured. Was used as an index of life as half-life time (τ0.5). For the measurement, a spectral radiance meter CS-1000 (manufactured by Konica Minolta Sensing) was used in the same manner.

  From the table, it can be seen that the organic EL device of the present invention has higher external extraction quantum efficiency and less change in driving voltage over time than the comparative example. In particular, the effect is significant at Δ1, which is an index value when it is reduced by 30% from the initial luminance, and the performance improvement degree is particularly high in lighting applications that place importance on this index value. It is clear that it is useful as a material. The effect of the present invention is remarkable when used as a charge transport material used for a hole transport material layer, an electron transport material layer, or the like.

Example 6
<Production of full-color display device>
(Blue light emitting organic EL device)
The organic EL element 1-13 produced in Example 1 was used.

(Green light-emitting organic EL device)
The organic EL element 5-1 produced in Example 5 was used.

(Red light emitting organic EL device)
The organic EL element 3-6 produced in Example 3 was used.

  It was found that the produced organic EL element exhibited blue, green, and red light emission by applying a voltage to each electrode, and could be used as a full-color display device.

Example 7
《Preparation of white light emitting lighting device》
The white light-emitting organic EL element 1-13W was similarly obtained except that D-33 of the organic EL element 1-1 produced in Example 1 was changed to a ternary mixture of D-15, D-21, and D-33. Was made. The obtained organic EL element 1-13W was covered with a glass case on the non-light emitting surface to obtain a lighting device. The illuminating device could be used as a thin illuminating device that emits white light with high luminous efficiency and long emission life.

DESCRIPTION OF SYMBOLS 1 Display 3 Pixel 5 Scan line 6 Data line 7 Power supply line 10 Organic EL element 11 Switching transistor 12 Drive transistor 13 Capacitor A Display part B Control part 101 Glass substrate 102 ITO transparent electrode 103 Partition 104 104 Hole injection layer 105B, 105G, 105R Luminescent layer 106 Cathode 207 Glass substrate with transparent electrode 206 Organic EL layer 205 Cathode 202 Glass cover 208 Nitrogen gas 209 Water catching agent

Claims (10)

In an organic electroluminescence device having a plurality of organic compound layers including a hole transport layer, a light emitting layer, and an electron transport layer sandwiched between an anode and a cathode, at least one of the organic compound layers is represented by the following general formula (1) The organic electroluminescent element characterized by containing the cyclic oligo naphthalene compound represented by these.

(In the formula, A _{1 to} A ₆ each independently represent CR ₁ to CR ₆ or a nitrogen atom. R _{1 to} R ₆ each independently represents a hydrogen atom, an alkyl group, an alkenyl group, an alkynyl group, an alkoxy group, Alkylthio group, aryl group, aryloxy group, arylthio group, arylalkyl group, arylalkoxy group, arylalkylthio group, arylalkenyl group, arylalkynyl group, heteroaryl group, heteroaryloxy group, heteroarylthio group, heteroarylalkyl Group, heteroarylalkoxy group, heteroarylalkylthio group, heteroarylalkenyl group, heteroarylalkynyl group, amino group, substituted amino group, silyl group, substituted silyl group, halogen atom, acyl group, acyloxy group, imine residue, amide Group, acid imide group A monovalent heterocyclic group, carboxyl group, substituted carboxyl group, a cyano group or a nitro group, _{R 1} and _R 2, _{R 3} and _R 4, _{R 4} and _{R 5} and _{R 5} and _{R 6} are respectively bonded to each other And n may be an integer of 3 to 10.)   The organic electroluminescence device according to claim 1, wherein the organic compound layer containing the cyclic oligonaphthalene compound is a light emitting layer.   The organic electroluminescence device according to claim 1, wherein the organic compound layer containing the cyclic oligonaphthalene compound is a hole transport layer.   The organic electroluminescence device according to claim 1, wherein the organic compound layer containing the cyclic oligonaphthalene compound is an electron transport layer. The organic light-emitting device according to claim 2, wherein the light-emitting layer contains a phosphorescent organic metal complex compound, and at least one of them is a compound represented by the following general formula (2).

(In the formula, P and Q represent a carbon atom or a nitrogen atom, A1 represents an atomic group which forms an aromatic hydrocarbon ring or an aromatic heterocycle with PC, and A2 represents an aromatic hydrocarbon with QN. P1-L1-P2 represents a bidentate ligand, P1 and P2 each independently represent a carbon atom, a nitrogen atom, or an oxygen atom, and L1 represents P1. , P2 represents an atomic group forming a bidentate ligand, r represents an integer of 1 to 3, s represents an integer of 0 to 2, and r + s is 2 or 3. M ₁ is an element Represents a group 8-10 metal element in the periodic table.)   The organic electroluminescence device according to claim 3, wherein the hole transport layer contains an acceptor material.   The organic electroluminescence device according to claim 4, wherein the electron transport layer contains a donor material.   An illuminating device comprising the organic electroluminescence element according to claim 1.   A display device comprising the organic electroluminescence element according to claim 1.   It is a manufacturing method of the organic electroluminescent element of any one of Claims 1-7, Comprising: The layer containing the cyclic oligo naphthalene compound represented by the said General formula (1) among organic layers is a wet method ( A method for producing an organic electroluminescence element, wherein the film is formed and formed by a wet process.

Images