JP2009152435A - White organic electroluminescent device, manufacturing method thereof, display unit, and lighting apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a white organic EL device excellent in external extraction quantum efficiency and lifetime, and also to provide a manufacturing method for the device, and a display unit and a lighting apparatus equipped with the device. <P>SOLUTION: The white organic electroluminescent device has many organic layers including at least two light-emitting layers interposed between an anode-side substrate and a cathode-side substrate. A first light-emitting layer nearest to the anode-side substrate among the light-emitting layers, contains at least one of hole transportation material, and at least one of organometallic complex which has a light-emitting wavelength of 600 to 640 nm. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to a white organic electroluminescent element, a method for manufacturing a white organic electroluminescent element, a display device, and a lighting device.

  Conventionally, as a light-emitting electronic display device, there is an electroluminescence display (hereinafter abbreviated as ELD). As a constituent element of ELD, an inorganic electroluminescence element (hereinafter also referred to as an inorganic EL element) and an organic electroluminescence element (hereinafter also referred to as an organic EL element) can be given.

  Inorganic EL elements have been used as planar light sources, but an alternating high voltage is required to drive the light emitting elements.

  On the other hand, an organic EL element has a structure in which a light emitting layer containing a compound that emits light is sandwiched between a cathode and an anode. By injecting electrons and holes into the light emitting layer and recombining them, excitons (exciton) are obtained. Is a device that emits light by utilizing the emission of light (fluorescence / phosphorescence) when the exciton is deactivated, and can emit light at a voltage of several V to several tens of V. Therefore, it has a wide viewing angle, high visibility, and since it is a thin-film type complete solid-state device, it is attracting attention from the viewpoints of space saving and portability.

  Another major feature of the organic EL element is that it is a surface light source unlike main light sources conventionally used in practice, such as light-emitting diodes and cold-cathode tubes. Applications that can effectively utilize this characteristic include illumination light sources and various display backlights. In particular, it is also suitable to be used as a backlight of a liquid crystal full color display whose demand has been increasing in recent years.

  Improvement of luminous efficiency is mentioned as a subject for using an organic EL element as such an illumination light source or a backlight of a display. As a means for improving luminous efficiency, there is a method in which an organic functional layer (hereinafter also referred to as an organic layer) constituting an organic EL element is formed by laminating a plurality of layers each having a separate function. For example, a layer structure such as a hole transport layer / a light emitting layer / an electron transport layer can be given.

  Recently, organic EL elements that emit white light have been attracting a great deal of attention, including for lighting applications.

Conventionally, as an organic EL element that emits white light,
(A) providing a plurality of light emitting layers such as R (red), G (green), and B (blue);
(B) mixing a plurality of luminescent materials, for example, R (red), G (green), and B (blue) luminescent materials;
(C) The light emitting material itself uses a compound exhibiting white light emission as the light emitting material.
Etc. are known (see, for example, Patent Documents 1, 2, and 3).

  As methods for producing these white organic EL elements, there are a vapor deposition method, a wet process (spin coating method, casting method, ink jet method, spray method, printing method) and the like, but a vacuum process is not required and continuous production is simple. For some reason, in recent years, a manufacturing method in a wet process has attracted attention.

  On the other hand, an organic EL element manufacturing method using a wet process has attracted a great deal of attention due to advantages such as an increase in area and cost, but it is difficult to form a stacked layer of organic layers (when an upper layer is applied and formed) Damage to the lower layer), it has not yet reached its full performance.

  Therefore, white light-emitting elements that can be manufactured by a wet process are difficult to use by using a plurality of light-emitting layers that are commonly used in vapor deposition. Therefore, it is achieved by adding a plurality of colors of light-emitting materials in one light-emitting layer. Yes.

Furthermore, in the case of the above-mentioned (c), there are problems such that it is difficult to tune the luminescent color because the ratio of the compound itself is large and the special property is strong.
JP 2007-27092 A JP 2003-86376 A JP 2007-99723 A

  The objective of this invention is providing the white organic EL element excellent in the external extraction quantum efficiency and lifetime, the manufacturing method of this element, the display apparatus provided with this element, and an illuminating device.

  The above object of the present invention has been achieved by the following constitution.

1. In the white organic electroluminescence device having a plurality of organic layers including at least two light emitting layers sandwiched between the anode side substrate and the cathode side substrate,
The first light emitting layer closest to the anode side substrate in the light emitting layer contains at least one hole transport material and at least one organometallic complex, and the emission wavelength of the organometallic complex is 600 nm to 640 nm. A white organic electroluminescence device characterized in that

  2. 2. The white organic electroluminescence device as described in 1 above, wherein the hole transport material has a plurality of polymerizable groups.

  3. 3. The white organic electroluminescence device as described in 2 above, wherein the polymerizable group represents a vinyl group or an allyl group.

  4). 4. The white organic electroluminescence device according to any one of 1 to 3, wherein at least one of the organometallic complexes has a compound represented by the following general formula (1) as a ligand.

[Wherein, Ar ₁ and Ar ₂ each represent a 5-membered or 6-membered aromatic ring. ]
5. In manufacturing the white organic electroluminescent element of any one of said 1-4, at least 1 layer of the said light emitting layer has a process formed by a wet process, The white organic electroluminescent element characterized by the above-mentioned. Manufacturing method.

  6). 5. A display device comprising the white organic electroluminescence element according to any one of 1 to 4 above.

  7. 5. A lighting device comprising the white organic electroluminescence element according to any one of 1 to 4 above.

  According to the present invention, it was possible to provide a white organic EL element excellent in external extraction quantum efficiency and lifetime, a method for producing the element, a display device including the element, and a lighting device.

  In the white organic EL device of the present invention, the configuration according to any one of claims 1 to 4 can provide a white organic EL device having a high external extraction quantum efficiency and a long emission lifetime. It was. In addition, it was possible to provide a method for producing a white organic EL element, a display device including the white organic EL element, and a lighting device.

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

As described in claim 1, the organic EL device of the present invention is a white organic electroluminescence device having a plurality of organic layers including at least two light emitting layers sandwiched between an anode side substrate and a cathode side substrate.
The first light emitting layer closest to the anode side substrate in the light emitting layer contains at least one hole transport material and at least one organometallic complex, and the emission wavelength of the organometallic complex is 600 nm to 640 nm. It is characterized by being.

  The structure of a plurality of organic layers including the anode side substrate, the cathode side substrate, and at least two light emitting layers according to the white organic EL element of the present invention will be described in detail later. The at least one hole transport material contained in the first light emitting layer closest to the substrate and the organometallic complex exhibiting an emission wavelength of 600 nm to 640 nm will be described.

<< Hole transport material contained in the first light emitting layer >>
The first light emitting layer according to the present invention refers to at least one positive light emitting layer closest to the anode side substrate among at least two light emitting layers constituting the white organic EL device of the present invention. Although a hole transport material is included, the hole transport material is preferably a compound having a polymerizable group, and more preferably a compound having a plurality of polymerizable groups.

(Hole transport material having a polymerizable group (also referred to as a hole transport compound))
The hole transport material having a polymerizable group that is preferably used in the first light-emitting layer according to the present invention and the hole transport material having a plurality of polymerizable groups that are preferably used will be described.

  Here, the polymerizable group may be any group that can cause radical polymerization reaction, ionic polymerization reaction, condensation polymerization reaction, and the like. For example, vinyl group, vinyloxy group, acryloyl group, methacryloyl group, mercapto group, Examples include hydroxy groups, carboxy groups, cyanate groups, isocyanate groups, thiocyanate groups, isothiocyanate groups, groups derived from oxirane (ethylene oxide) (epoxy groups), groups derived from trimethylene oxide (oxetane), and the like. .

  Among the above, a vinyl group and an allyl group are preferably used.

  As the hole transport material, a hole transport material (hole transport compound) used in a hole transport layer having a layer structure of an organic EL element described later will be described in detail.

  Hereinafter, although the specific example of the positive hole transport material (hole transport compound) which has several polymeric group which concerns on this invention is given, this invention is not limited to these.

<< Organic metal complex contained in the first light emitting layer >>
The organometallic complex contained in the first light-emitting layer according to the present invention has an emission wavelength of 600 nm to 640 nm, but preferably has a compound represented by the general formula (1) as a ligand. .

(Compound represented by formula (1) and organometallic complex having the compound as a ligand)
The compound represented by the general formula (1) and the organometallic complex having the compound as a ligand will be described.

In the general formula (1), a 5-membered or 6-membered aromatic ring represented by Ar ₁ or Ar ₂ (wherein the aromatic ring represents an aromatic hydrocarbon ring or an aromatic heterocycle). , Benzene ring, oxazole ring, thiophene ring, furan ring, pyrrole ring, pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring, diazine ring, triazine ring, imidazole ring, oxadiazole ring, oxatriazole ring, tetrazole ring, thiadiazole Ring, thiatriazole ring, isothiazole ring, isoxazole ring, pyrazole ring, triazole ring and the like.

  The 5-membered or 6-membered aromatic ring may have a substituent. Examples of the substituent include 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, phena Tolyl 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) One is replaced by a nitrogen atom) Xalinyl group, pyridazinyl group, triazinyl group, quinazolinyl group, phthalazinyl group, etc.), heterocyclic group (eg, pyrrolidyl group, imidazolidyl group, morpholyl group, oxazolidyl group, etc.), alkoxy group (eg, methoxy group, ethoxy group, propyloxy) 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.), A reelthio group (eg, phenylthio group, naphthylthio group, etc.), an alkoxycarbonyl group (eg, methyloxycarbonyl group, ethyloxycarbonyl group, butyloxycarbonyl group, octyloxycarbonyl group, dodecyloxycarbonyl group, etc.), aryloxycarbonyl group (Eg, phenyloxycarbonyl group, naphthyloxycarbonyl group, etc.), sulfamoyl group (eg, aminosulfonyl group, methylaminosulfonyl group, dimethylaminosulfonyl group, butylaminosulfonyl group, hexylaminosulfonyl group, cyclohexylaminosulfonyl group, octyl) Aminosulfonyl group, dodecylaminosulfonyl group, phenylaminosulfonyl group, naphthylaminosulfonyl group, 2-pyridylaminosulfonyl group, etc.), acyl (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 group (for example, acetyloxy group, ethylcarbonyloxy group, butylcarbonyloxy group, octylcarbonyloxy group, dodecylcarbonyloxy group, phenylcarbonyloxy group, etc.), amide group (for example, methylcarbonylamino group, ethylcarbonylamino group) Dimethylcarbonylamino group, propylcarbonylamino group, pentylcarbonylamino group, cyclohexylcarbonylamino group, 2-ethylhexylcarbonylamino Octylcarbonylamino group, dodecylcarbonylamino group, phenylcarbonylamino group, naphthylcarbonylamino group, etc.), carbamoyl group (for example, aminocarbonyl group, methylaminocarbonyl group, dimethylaminocarbonyl group, propylaminocarbonyl group, pentylaminocarbonyl) Group, cyclohexylaminocarbonyl group, octylaminocarbonyl group, 2-ethylhexylaminocarbonyl group, dodecylaminocarbonyl group, phenylaminocarbonyl group, naphthylaminocarbonyl group, 2-pyridylaminocarbonyl group, etc.), ureido group (for example, methylureido group) Ethyl ureido group, pentyl ureido group, cyclohexyl ureido group, octyl ureido group, dodecyl ureido group, phenyl ureido 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, dimethylamino) 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, trimethyl group) Isopropylsilyl group, triphenylsilyl group, phenyldiethylsilyl group, etc.) and phosphono group.

  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.

  Hereinafter, although the specific example of the organometallic complex which has a compound represented by General formula (1) as a ligand is given, this invention is not limited to these.

  All of the above specific examples have been confirmed to have an emission wavelength of 600 nm to 640 nm.

  Moreover, the 1st light emitting layer which concerns on this invention may contain the reactive light emission dopant which has a polymeric group as shown below.

  In addition, the organometallic complex which has the compound represented by said general formula (1) as a ligand, and the reactive luminescent dopant which has said polymeric group are mentioned in Inorg. Chem. It can be synthesized by referring to the method described in Vol. 40, 1704-1711.

  Hereinafter, the detail of each component of the white organic EL element of this invention is demonstrated sequentially.

<< Layer configuration of white organic EL element >>
Next, although the preferable specific example of the layer structure of the white organic EL element of this invention is shown below, this invention is not limited to these.

(I) Anode / light emitting layer unit / electron transport layer / cathode (ii) Anode / hole transport layer / light emitting layer unit / electron transport layer / cathode (iii) Anode / hole transport layer / light emitting layer unit / hole blocking Layer / electron transport layer / cathode (iv) anode / hole transport layer / light emitting layer unit / hole blocking layer / electron transport layer / cathode buffer layer / cathode (v) anode / anode buffer layer / hole transport layer / light emission Layer unit / hole blocking layer / electron transport layer / cathode buffer layer / cathode << 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 thickness of the light emitting layer is not particularly limited, but from the viewpoint of the uniformity of the film to be formed, the application of unnecessary high voltage during light emission, and the improvement of the stability of the emission color with respect to the drive current. It is preferable to adjust to the range of 2 nm-200 nm, More preferably, it adjusts to the range of 5 nm-100 nm.

  The light emitting layer of the organic EL device of the present invention preferably contains at least one kind of a light emitting host compound and a light emitting dopant as a guest material, and more preferably contains a light emitting host compound and three or more kinds of light emitting dopants. A host compound (also referred to as a light-emitting host) and a light-emitting dopant (also referred to as a light-emitting dopant compound) included in the light-emitting layer are described below.

(Host compound)
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.

  As the host compound, known host compounds may be used alone or in combination of two or more. 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 can thereby obtain arbitrary luminescent colors.

  The light emitting host used in the present invention may be a conventionally known low molecular compound or a high molecular compound having a repeating unit, and a low molecular compound having a polymerizable group such as a vinyl group or an epoxy group (deposition polymerization property). Light emitting host).

  As the known host compound that may be used in combination, 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) is preferable.

  Specific examples of known host compounds include 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. 2002-260861, No. 2002-280183, No. 2002-299060, No. 2002. -302516, 2002-305083, 2002-305084, 2002-308837, and the like.

  Hereinafter, although the specific example of the compound preferably used as a host compound of the light emitting layer of the organic EL element of this invention is given, this invention is not limited to these.

  Moreover, although the reactive host compound which has a polymeric group shown below for formation of a light emitting layer is used preferably, this invention is not limited to these.

(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 a white organic EL device with high luminous efficiency, the above-mentioned host compound is used as the light emitting dopant (sometimes simply referred to as a light emitting material) used in the light emitting layer or light emitting unit of the white organic EL device of the present invention. It is preferable to contain a phosphorescent dopant at the same time.

  Among the light emitting dopants according to the present invention, in the white organic EL element of the present invention, at least one organometallic complex is used as described above for the first light emitting layer closest to the anode side substrate, The emission wavelength of the organometallic complex is characterized by being in the range of 600 nm to 640 nm.

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

  The phosphorescent dopant 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 dopant 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 dopants in principle. One is the recombination of carriers on the host compound to which carriers are transported to generate an excited state of the host compound, and this energy is transferred to the phosphorescent dopant. Energy transfer type to obtain light emission from the phosphorescent dopant, and the other is that the phosphorescent dopant becomes a carrier trap, carrier recombination occurs on the phosphorescent dopant, and the phosphorescent dopant In any case, the excited state energy of the phosphorescent dopant is required to be lower than the excited state energy of the host compound.

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

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

(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 a constituent layer of the organic EL element according to 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 driving 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 represented by lithium, alkali metal compound buffer layer represented by lithium fluoride, alkaline earth metal compound buffer layer represented by magnesium fluoride, oxide buffer layer represented by aluminum oxide, etc. . The buffer layer (injection layer) is preferably a very thin film, and although it depends on the material, the film thickness is preferably in the range of 0.1 nm to 5 μm.

<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 according to the present invention is preferably provided adjacent to the light emitting layer.

  The hole blocking layer preferably contains the azacarbazole derivative mentioned as the host compound.

  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 nm 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.

  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, these materials are preferably used because a light-emitting element with higher efficiency can be obtained.

  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. it can. About the film thickness of a positive hole transport layer, it is preferable that it is the range of 5 nm-5 micrometers, More preferably, it is 5 nm-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, and JP-A-2001-102175. 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.

  Hereinafter, although the specific example of the compound preferably used together for formation of the positive hole transport layer of the white organic EL element of this invention is given, this invention is not limited to these.

《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. As long as it has a function of transferring electrons to the light-emitting layer, any material can be selected and used from among conventionally known compounds. For example, nitro-substituted fluorene derivatives, diphenylquinone derivatives Thiopyrandioxide derivatives, carbodiimides, fluorenylidenemethane derivatives, anthraquinodimethane and anthrone derivatives, oxadiazole derivatives and the like.

  Furthermore, in the above oxadiazole derivative, a thiadiazole derivative in which the oxygen atom of the oxadiazole ring is substituted with a sulfur atom, and 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.

  Also, 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), etc., and the central metals of these metal complexes are In, Mg, Cu , Ca, Sn, Ga, or Pb can also be used as an 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 hole transport layer Can also be used as an electron transporting 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 nm-200 nm. The electron transport layer may have a single layer structure composed of one or more of the above materials.

  Alternatively, an electron transport layer with high n property doped with impurities as a guest material can 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.

  Hereinafter, although the specific example of the compound (electron transport material) preferably used together for formation of the electron carrying layer of the white organic EL element of this invention is given, this invention is not limited to these.

  Moreover, the electron carrying layer which concerns on this invention may contain the reactive electron transport material which has a polymeric group as shown below.

<Condensation polymer>
In the method for producing a white organic EL element of the present invention, in addition to the constituent material of the organic layer of the organic EL element, the following condensation polymers can be used as appropriate.

  Hereinafter, although the specific example of the condensation polymer used for this invention is given, this invention is not limited to these.

"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 substances 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, the range of 10 nm to 1000 nm is preferable, and the range of 10 nm to 200 nm is more preferable.

"cathode"
As the cathode, a material having a 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, Suitable are a magnesium / aluminum mixture, a magnesium / indium mixture, an aluminum / aluminum oxide (Al ₂ O ₃ ) mixture, a lithium / aluminum mixture, aluminum and the like.

  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 preferably in the range of 10 nm to 5 μm, more preferably in the range of 50 nm 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.

"substrate"
As a substrate (hereinafter also referred to as a base, a base material, a support substrate, a support, etc.) that can be used in the organic EL device according to the present invention, there is no particular limitation on the type of glass, plastic, etc., and it is transparent. Or opaque. When extracting light from the substrate side, the substrate is preferably transparent. Examples of the transparent substrate preferably used include glass, quartz, and a transparent resin film. A particularly preferable 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, cellulose acetate butyrate, cellulose acetate propionate (CAP), Cellulose esters such as cellulose acetate phthalate (TAC) and cellulose nitrate or derivatives thereof, polyvinylidene chloride, polyvinyl alcohol, polyethylene vinyl alcohol, syndiotactic polystyrene, polycarbonate, norbornene resin, polymethylpentene, polyether ketone, polyimide , Polyethersulfone (PES), polyphenylene sulfide, polysulfones Cycloolefin resins such as polyetherimide, polyetherketoneimide, polyamide, fluororesin, nylon, polymethylmethacrylate, acrylic or polyarylate, Arton (trade name, manufactured by JSR) or Appel (trade name, manufactured by Mitsui Chemicals) Can be mentioned.

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, but an atmospheric pressure plasma polymerization method as described in JP-A-2004-68143 is particularly preferable.

  Examples of the opaque substrate include a metal plate such as aluminum and stainless steel, a film, an opaque resin substrate, a ceramic substrate, and the like.

  The external extraction efficiency at room temperature of light emission of the organic EL device according to 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 of the organic EL element 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 organic EL element can be thinned.

Furthermore, the polymer film, measured oxygen permeability by the method based on JIS K 7126-1987 is ^{1 × 10 -3 ml / m 2} / 24h or less, as measured by the method based on JIS K 7129-1992 water vapor transmission rate (25 ± 0.5 ° C., relative humidity (90 ± 2)% RH) is preferably that of ^{1 × 10 -3 g / (m} 2 / 24h) 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 possible to suitably form an inorganic or organic layer as a sealing film by covering the electrode and the organic layer on the outer side of the electrode facing the substrate with the organic layer interposed therebetween, and in contact with the substrate. 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 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 of improving the light extraction efficiency, for example, a method of forming irregularities on the surface of the transparent substrate and preventing total reflection at the transparent substrate and the air interface (US Pat. No. 4,774,435), A method for improving efficiency by giving light condensing property to a substrate (Japanese Patent Laid-Open No. 63-314795), a method for forming a reflective surface on the side surface of an organic EL element (Japanese Patent Laid-Open No. 1-220394), a substrate A method of forming an antireflection film by introducing a flat layer having an intermediate refractive index between the substrate and the light emitter (Japanese Patent Laid-Open No. 62-172691), and lowering the refractive index than the substrate between the substrate and the light emitter. A method of introducing a flat layer having a structure (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) No. 283751) .

  In the present invention, these methods can be used in combination with the organic EL device according to 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, A method of forming a diffraction grating between any layers of the transparent 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 organic EL device having further high 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, more 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.

《Condensing sheet》
The organic EL device according to the present invention can be processed on the light extraction side of the substrate, for example, by providing a microlens array-like structure, 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 μm 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.

<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.

Further, when the organic EL element according to the present invention is a white element, white means that the chromaticity in the CIE 1931 color system at 1000 cd / m ² is measured when the front luminance at 2 ° viewing angle is measured by the above method. It means that it is in the region of X = 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.

  In the case of applying a DC voltage to the obtained multicolor display device, light emission can be observed by applying a voltage of about 2V to 40V 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 maintained 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.

《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.

  Further, 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. Since other layers are common, patterning of the mask or the like is not necessary. 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 diagram of a lighting device, and the organic EL element 101 of the present invention is covered with a glass cover 102 (in addition, the sealing operation with the glass cover is to bring the organic EL element 101 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).

  FIG. 6 shows a cross-sectional view of the lighting device. In FIG. 6, 105 denotes a cathode, 106 denotes an organic EL layer, and 107 denotes a glass substrate with a transparent electrode. The glass cover 102 is filled with nitrogen gas 108 and a water catching agent 109 is provided.

  EXAMPLES Hereinafter, although an Example demonstrates this invention, this invention is not limited to these.

Example 1
<< Production of Organic EL Element 1-1 >>
A transparent substrate provided with this ITO transparent electrode after patterning a substrate (NH45 manufactured by NH Techno Glass Co., Ltd.) on which a 100 nm ITO (indium tin oxide) film is formed on a glass substrate of 100 mm × 100 mm × 1.1 mm as an anode The supporting substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and UV ozone cleaning was performed 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 30 nm-thick hole transport layer.

  On this anode side substrate, a solution of 30 mg MO-23 and 3 mg PD-10 dissolved in 5 ml of toluene was formed by spin coating at 1000 rpm for 30 seconds, and at 150 ° C. under nitrogen. A first light emitting layer having a film thickness of 30 nm comprising a polymerized film of MO-23 in which heating is performed for 1 hour to polymerize the polymerizable group of MO-23 and, as a result, PD-10 is doped by the heat treatment. Was provided.

  Further, a solution prepared by dissolving 30 mg of OC-15, 3 mg of PD-12, and 2 mg of PD-1 in 3 ml of toluene was formed on this first light emitting layer by spin coating at 1500 rpm for 30 seconds. And dried at 60 ° C. for 1 hour to provide a second light-emitting layer having a thickness of 40 nm.

This substrate was fixed to a substrate holder of a commercially available vacuum deposition apparatus, attached to the vacuum deposition apparatus, and the vacuum chamber was depressurized to 4 × 10 ⁻⁴ Pa.

  Bis (2-methyl-8-quinolate) -p-phenylphenolate aluminum complex (BAlq) was deposited to a thickness of 50 nm to form an electron transport layer.

  Furthermore, 1 nm of lithium fluoride as a cathode buffer layer and 110 nm of aluminum as a cathode were vapor-deposited to form a cathode, and an organic EL device 1-1 was produced.

<< Production of Organic EL Element 1-2 >>
A transparent substrate provided with this ITO transparent electrode after patterning a substrate (NH45 manufactured by NH Techno Glass Co., Ltd.) on which a 100 nm ITO (indium tin oxide) film is formed on a glass substrate of 100 mm × 100 mm × 1.1 mm as an anode The supporting substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and UV ozone cleaning was performed 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 30 nm-thick hole transport layer.

  A solution prepared by dissolving 30 mg of MO-23, 3 mg of PD-1 and 0.2 mg of PD-10 in 5 ml of toluene was formed on this anode side substrate by spin coating at 1000 rpm for 30 seconds. And heating at 150 ° C. for 1 hour under nitrogen to polymerize the polymerizable group of MO-23, resulting in the insolubilization treatment of MO-23 doped with PD-1 and PD-10 by the heat treatment. A first light emitting layer having a thickness of 30 nm made of a polymerized film was provided.

  Further, a solution obtained by dissolving 30 mg of OC-15 and 3 mg of PD-12 in 3 ml of toluene was formed on this first light emitting layer by spin coating at 1500 rpm for 30 seconds, and at 60 ° C. It dried for 1 hour and provided the 2nd light emitting layer with a film thickness of 40 nm.

This substrate was fixed to a substrate holder of a commercially available vacuum deposition apparatus, attached to the vacuum deposition apparatus, and the vacuum chamber was depressurized to 4 × 10 ⁻⁴ Pa. Bis (2-methyl-8-quinolate) -p-phenylphenolate aluminum complex (BAlq) was deposited to a thickness of 50 nm to form an electron transport layer.

  Further, lithium fluoride 1 nm was deposited as a cathode buffer layer and aluminum 110 nm was deposited as a cathode to form a cathode, and an organic EL element 1-2 was produced.

<< Production of Organic EL Element 1-3 >>
A transparent substrate provided with this ITO transparent electrode after patterning a substrate (NH45 manufactured by NH Techno Glass Co., Ltd.) on which a 100 nm ITO (indium tin oxide) film is formed on a glass substrate of 100 mm × 100 mm × 1.1 mm as an anode The supporting substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and UV ozone cleaning was performed 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 30 nm-thick hole transport layer.

  A solution prepared by dissolving 30 mg of MO-23, 3 mg of PD-1 and 0.2 mg of PD-10 in 5 ml of toluene was formed on this anode side substrate by spin coating at 1000 rpm for 30 seconds. And heating at 150 ° C. for 1 hour under nitrogen to polymerize the polymerizable group of MO-23, resulting in the insolubilization treatment of MO-23 doped with PD-1 and PD-10 by the heat treatment. A first light emitting layer having a thickness of 30 nm made of a polymerized film was provided.

  Further, a solution obtained by dissolving 30 mg of OC-15 and 3 mg of PD-9 in 3 ml of toluene was formed on this first light emitting layer by spin coating at 1500 rpm for 30 seconds, and at 60 ° C. It dried for 1 hour and provided the 2nd light emitting layer with a film thickness of 40 nm.

This substrate was fixed to a substrate holder of a commercially available vacuum deposition apparatus, attached to the vacuum deposition apparatus, and the vacuum chamber was depressurized to 4 × 10 ⁻⁴ Pa. Bis (2-methyl-8-quinolate) -p-phenylphenolate aluminum complex (BAlq) was deposited to a thickness of 50 nm to form an electron transport layer.

  Further, lithium fluoride 1 nm was deposited as a cathode buffer layer and aluminum 110 nm was deposited as a cathode to form a cathode, and an organic EL element 1-3 was produced.

<< Preparation of Organic EL Element 1-4 (Comparative Example) >>
A transparent substrate provided with this ITO transparent electrode after patterning a substrate (NH45 manufactured by NH Techno Glass Co., Ltd.) on which a 100 nm ITO (indium tin oxide) film is formed on a glass substrate of 100 mm × 100 mm × 1.1 mm as an anode The supporting substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and UV ozone cleaning was performed 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.

  A solution obtained by dissolving 30 mg of MO-23 in 5 ml of toluene was formed on this anode side substrate by spin coating under conditions of 1000 rpm and 30 seconds, heated at 150 ° C. for 1 hour under nitrogen, and MO- An insolubilization treatment was performed by polymerizing 23 polymerizable groups. As a result, a second hole transport layer having a thickness of 30 nm made of a polymerized film of MO-23 was provided by heat treatment.

  Further, a solution of 30 mg of OC-15, 1 mg of PD-1, 0.05 mg of PD-10, and 3 mg of PD-9 in 3 ml of toluene was added to this second hole transport layer at 1500 rpm, 30 A film was formed by spin coating under the condition of seconds, and dried at 60 ° C. for 1 hour to provide a light-emitting layer having a thickness of 40 nm.

This substrate was fixed to a substrate holder of a commercially available vacuum deposition apparatus, attached to the vacuum deposition apparatus, and the vacuum chamber was depressurized to 4 × 10 ⁻⁴ Pa. Bis (2-methyl-8-quinolate) -p-phenylphenolate aluminum complex (BAlq) was deposited to a thickness of 50 nm to form an electron transport layer.

  Furthermore, 1 nm of lithium fluoride as a cathode buffer layer and 110 nm of aluminum as a cathode were vapor-deposited to form a cathode, thereby fabricating an organic EL element 1-4.

<< Evaluation of Organic EL Elements 1-1 to 1-4 >>
When evaluating the obtained organic EL elements 1-1 to 1-4, the non-light-emitting surface of each organic EL element after production is covered with a glass case, and a glass substrate having a thickness of 300 μm is used as a sealing substrate. An epoxy-based photo-curing adhesive (Lux Track LC0629B manufactured by Toagosei Co., Ltd.) is applied as a sealing material in the periphery, and this is placed on the cathode to be in close contact with the transparent support substrate and irradiated with UV light from the glass substrate side Then, it was cured and sealed, and an illumination device as shown in FIGS. 5 and 6 was formed and evaluated.

《External extraction quantum efficiency》
About the produced organic EL element, the external extraction quantum efficiency (%) when a ^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 Minolta) was used.

<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 (τ ^0.5 ). In addition, the spectral radiance meter CS-1000 (made by Minolta) was similarly used for the measurement.

  The measurement results of the external extraction quantum efficiency, the light emission lifetime, and the driving voltage of the organic EL elements 1-1 to 1-4 were evaluated by relative evaluation when the organic EL element 1-3 was set to 100.

  The results obtained are shown below.

Organic EL element External extraction quantum efficiency Luminescence lifetime Remarks 1-1 110 1800 Present invention 1-2 109 1500 Present invention 1-3 103 140 Present invention 1-4 100 100 Comparative example From the above, the organic EL element of the present invention has high light emission. It is clear that the light emission life is long with efficiency, and it can be seen that it is suitable for practical use as a thin lighting device that emits white light.

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.

Explanation of symbols

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 Organic EL element 102 Glass cover 105 Cathode 106 Organic EL layer 107 Glass substrate with a transparent electrode 108 Nitrogen gas 109 Water catching agent

Claims (7)

In the white organic electroluminescence device having a plurality of organic layers including at least two light emitting layers sandwiched between the anode side substrate and the cathode side substrate,
The first light emitting layer closest to the anode side substrate in the light emitting layer contains at least one hole transport material and at least one organometallic complex, and the emission wavelength of the organometallic complex is 600 nm to 640 nm. A white organic electroluminescence device characterized in that The white organic electroluminescence device according to claim 1, wherein the hole transport material has a plurality of polymerizable groups. The white organic electroluminescence device according to claim 2, wherein the polymerizable group represents a vinyl group or an allyl group. The at least 1 sort (s) of the said organometallic complex has a compound represented by following General formula (1) as a ligand, The white organic electroluminescent element of any one of Claims 1-3 characterized by the above-mentioned. .

[Wherein, Ar ₁ and Ar ₂ each represent a 5-membered or 6-membered aromatic ring. ] When manufacturing the white organic electroluminescent element of any one of Claims 1-4, at least 1 layer of the said light emitting layer has a process formed with a wet process, The white organic electroluminescent characterized by the above-mentioned. Device manufacturing method. A display device comprising the white organic electroluminescence element according to claim 1. An illuminating device comprising the white organic electroluminescence element according to claim 1.

Images