JP2007088015A - ORGANIC ELECTROLUMINESCENCE ELEMENT AND METHOD FOR MANUFACTURING ORGANIC ELECTROLUMINESCENT DEVICE - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a stable organic EL element whose driving voltage is low and has no deterioration in luminance during long-time storage. <P>SOLUTION: The organic electroluminescence element includes a positive electrode, a negative electrode, and at least one layer of organic layer on a substrate. One layer out of the organic layers contains metal salt. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an organic electroluminescence element and a method for manufacturing the organic electroluminescence element.

  An organic electroluminescence (EL) element having a light emitting layer made of an organic compound is known to be driven at a low voltage, but generally has a higher driving voltage than an LED (light emitting diode) or the like.

  In particular, the “phosphorescent organic EL element” which is said to have high quantum efficiency of light emission has a problem because the driving voltage is higher than that of the fluorescent light emitting organic EL element.

  In general, it is possible to reduce the driving voltage by reducing the film thickness of the organic EL element. In this case, however, defects due to energization between the electrodes increase, and the yield decreases.

  As a technique for solving this, an attempt has been made to increase the conductivity of the charge transport layer by putting a dopant in a layer adjacent to the electrode, for example, the charge transport layer (for example, Patent Document 1). Among these, alkali metals, alkaline earth metals and organic compounds are used, and the driving voltage of the organic EL element can be lowered by these co-deposited films.

  However, the alkali metals and alkaline earth metals used here have a difficulty in handling.

  In particular, an alkali metal such as cesium metal has a small work function and a large doping effect, but metal cesium is unstable in the air and is very dangerous to handle.

  In view of these, it has been confirmed that the same effect can be obtained by an alkali metal or alkaline earth metal salt and an organic compound (for example, Patent Document 2 or 3).

However, regarding these metal salts, it was considered that the metal ions diffused during long-term storage of the organic EL device, but a decrease in luminance was observed.
JP-A-10-270172 JP 2004-193011 A JP 2004-335137 A

  Therefore, an object of the present invention is to obtain a stable organic EL device in which the driving voltage is reduced and the luminance is not lowered even during long-term storage.

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

  1. An organic electroluminescence device having an anode, a cathode and at least one organic layer on a substrate, wherein one layer of the organic layer contains a metal salt.

  2. 2. The organic electroluminescence device according to 1 above, wherein the organic layer containing the metal salt is adjacent to a cathode.

  3. 3. The organic electroluminescence device according to 2, wherein the organic layer containing the metal salt further contains a metal atom.

  4). 3. The organic electroluminescence device according to 2 above, wherein the thickness of the organic layer containing the metal salt is at least 20 nm.

  5. 5. The organic electroluminescence device according to any one of 1 to 4, wherein the metal salt is a sulfate.

  6). 5. The organic electroluminescence device according to any one of 1 to 4, wherein the metal salt is a salt of a carboxylic acid containing fluorine.

7). 5. The organic electroluminescence device according to any one of 1 to 4, wherein the counter anion of the metal salt is SCN ⁻ or NCS ⁻ .

  8). The organic electroluminescence device according to any one of 1 to 4, wherein a counter anion of the metal salt is represented by the following general formula (1).

[Wherein, R _{1 to} R ₄ each independently represents a substituent. ]
9. 5. The organic electroluminescence device according to any one of 1 to 4, wherein the counter anion of the metal salt is an anion having a pyridine ring, a bipyridine ring, and a terpyridine ring.

  10. 5. The organic electroluminescence device according to any one of 1 to 4, wherein the counter anion of the metal salt is represented by any one of the following general formulas (2-1) to (2-5).

[Wherein, R ₂₁ each independently represents a substituent, and the substituents may be bonded to form a ring. L ₁ represents a divalent linking group or a direct bond, and A ⁻ represents a substituent having an anion. n or m represents an integer of 5 or less, and in the general formula (2-1), m + n is an integer of 1 to 5, and m is at least 1. In the general formulas (2-2) to (2-4), m + n represents an integer of 1 to 4, and m is at least 1. In the general formula (2-5), m + n represents an integer of 1 to 3, and m is at least 1. ]
11. 5. The organic electroluminescence device according to any one of 1 to 4, wherein the counter anion of the metal salt is an anion having a macrocyclic structure.

  12 12. The organic electroluminescence device according to 11, wherein the anion having a macrocyclic structure is represented by the following general formula (3).

[In the formula, n represents an integer of 3 or more, and X independently represents an oxygen atom (—O—), a sulfur atom (—S—), —N (—LA ^— ) — at least one of X is N-L-a ^- a. Here, L represents a divalent linking group or a direct bond, and A ⁻ represents a substituent having an anion. ]
13. 13. The organic electroluminescence device according to any one of 1 to 12, wherein the metal salt is an alkali metal salt or an alkaline earth metal salt.

  14 13. The organic electroluminescence device according to any one of 1 to 12, wherein the metal salt is a lithium salt.

  15. 13. The organic electroluminescence device according to any one of 1 to 12, wherein the metal salt is a cesium salt.

  16. 13. The organic electroluminescence device according to any one of 1 to 12, wherein the metal salt is a sodium salt.

  17. 13. The organic electroluminescence device according to any one of 1 to 12, wherein the metal salt is a calcium salt.

  18. 18. The organic electroluminescence device according to any one of 1 to 17, further comprising a diffusion prevention layer that suppresses diffusion of metal ions constituting the metal salt.

  19. The organic electroluminescence device according to any one of 1 to 18, wherein the light emission includes light emission based on phosphorescence emission.

  20. The organic electroluminescence device as described in any one of 1 to 19 above, wherein the light emission contains at least a blue component.

  21. 21. The organic electroluminescence element according to any one of 1 to 20, wherein light emission is extracted from a direction opposite to the substrate.

  22. The organic electroluminescence device according to any one of 1 to 21, wherein the anode, the cathode, and the organic layer are manufactured by a vapor deposition method.

  23. In the manufacturing method of the organic electroluminescent element which manufactures the organic electroluminescent element of said 1-22, when metal salt is vapor-deposited, metal salt is pre-heated before vapor deposition of the organic electroluminescent element characterized by the above-mentioned. Production method.

  By using the metal salt of the present invention, it is possible to obtain a stable organic EL device in which a decrease in driving voltage can be reduced, power efficiency can be improved, and stability during long-term storage is improved.

  Hereinafter, the best mode for carrying out the present invention will be described in detail.

  The present invention is an organic electroluminescent device having an anode, a cathode, and at least one organic layer between the anode and the cathode, wherein one layer of the organic layer contains a metal salt. It is an organic electroluminescence element.

  As the metal salt, an alkali metal salt, an alkaline earth metal salt, or the like is preferable, and a lithium salt, a sodium salt, a cesium salt, or a calcium salt is particularly preferable.

  As mentioned in the above-mentioned references, alkali metals such as metal cesium, and alkali metal salts such as cesium fluoride, cesium chloride, lithium fluoride and calcium fluoride, which are salts of cesium, or alkaline earth metals An organic layer mixed with salt or the like is provided in an organic electroluminescence device having an anode, a cathode, and at least one organic layer between the anode and the cathode, so that the carrier electrode to the organic layer is provided. The barrier for injection can be lowered, and the drive voltage can be lowered in the organic EL element.

  For example, when a layer in which metal cesium or a cesium salt is mixed with an organic compound is inserted adjacent to the cathode between the electron transporting organic compound layer and the cathode, this causes electron injection from the cathode. The barrier can be lowered, and the driving voltage of the organic EL element having these can be greatly reduced.

  Since the electron injection process to the organic material on the cathode surface is reduction of the organic material on the cathode surface, it is an electron injection to the lowest unoccupied orbital level (LUMO) of the organic compound. . Therefore, the metal compound mixed and doped in the organic layer of the present invention may be any compound that lowers this lowest orbital level (LUMO) of the organic compound.

  These energy levels depend on the type of metal and metal compound to be doped, and are considered to be determined by the type of metal compound used, whether or not it is a stable level. That is, for example, the state of the metal or metal salt doped in the organic compound by co-evaporation or the like is not known in detail, but its form forms a stable level and determines the durability of the effect. Conceivable.

  However, the introduction of metal cesium requires attention because it is highly ignitable, and the introduction of the alkali metal or alkaline earth metal salt certainly leads to a decrease in driving voltage. It has been found that it does not continue to decrease over time or in repeated use, in other words, the performance deterioration of the organic EL element obtained thereby is large.

  In the present invention, avoiding the use of high-risk metal cesium, searching for various compounds from metal salts with low risk, preferably alkali metal salts and alkaline earth metal salts, These metal salts are based on the discovery of metal salt compounds that have a large effect on lowering the carrier injection barrier and that are sustained over time and have little deterioration by variously examining counter anions. .

  The present invention is a metal salt that has a known effect of lowering the carrier injection barrier, particularly alkali metal salts and alkaline earth metal salts. In the case of lithium salt, sodium salt, cesium salt, or calcium salt, a preferable effect is exhibited. In particular, the cesium salt has an excellent effect.

  In the case of a metal salt, unlike an alkali metal itself such as cesium, it is stable in the air, so that it is easy to handle and highly safe.

  For example, cesium salts have high deliquescence properties with respect to cesium fluoride, but many metal salts with counter anions according to the present invention have deliquescence properties. In order to evaporate simultaneously, it is preferable that the metal salt is sufficiently dried by preheating in a vacuum chamber in advance before vapor deposition. In particular, the water content is preferably 30 ppm or less.

  For drying, a drier, oven or the like can be used under vacuum, reduced pressure, or normal pressure. Depending on the salt used, preheating is performed in the range of 40 ° C. to 250 ° C. for 1 second to several hours. Thus, it is preferable to make the water content or less.

  The anion that becomes a counter ion of the alkali metal or alkaline earth metal (particularly preferably, lithium, sodium, cesium, calcium, etc.) according to the present invention will be described below.

First, sulfate ions (SO ₄ ²⁻ ) are preferable ions as the counter ions of the alkali metal or alkaline earth metal according to the present invention. For example, there is cesium sulfate.

In addition, as the counter anion of the metal salt, SCN ⁻ and NCS ⁻ are preferable, and a metal salt of a carboxylic acid containing fluorine is preferable.

  The carboxylate containing fluorine is an organic acid in which at least one of the substituents of the organic acid containing carboxylic acid is replaced with fluorine. For example, fluorine-substituted acetic acid (for example, trifluoroacetic acid), fluorine Examples thereof include substituted propionic acid and fluorine-substituted benzoic acid (for example, tetrafluorobenzoic acid). For example, cesium trifluoroacetate, lithium trifluoroacetate, calcium tetrafluorobenzoate and the like.

  Moreover, as an anion, the following organic anions are preferable as a counter ion of the metal salt concerning this invention.

  A preferred counter ion in the metal salt according to the present invention is represented by the general formula (1).

In the general formula (1), R _{1 to} R ₄ each independently represent a substituent.

Here, the substituent represented by R _{1 to} R ₄ includes an alkyl group (methyl group, ethyl group, i-propyl group, hydroxyethyl group, methoxymethyl group, trifluoromethyl group, t-butyl group, cyclopentyl group). Cyclohexyl group, benzyl group, etc.), aryl group (phenyl group, naphthyl group, p-tolyl group, p-chlorophenyl group etc.), heteroaryl group (pyrrole group, imidazolyl group, pyrazolyl group, pyridyl group, benzimidazolyl group, Benzothiazolyl group, benzoxazolyl group, triazolyl group, oxadiazolyl group, thiadiazolyl group, thienyl group, carbazolyl group etc.), alkenyl group (vinyl group, propenyl group, styryl group etc.), alkynyl group (ethynyl group etc.), non-aromatic Aromatic heterocyclic group (pyrrolidyl group, pyrazolyl group, imidazolyl group) Etc.), a silyl group (trimethylsilyl group, t- butyl dimethyl silyl group, dimethylphenyl silyl group, and a triphenylsilyl group, etc.) and the like. Each substituent may further have a substituent.

  Among these, an aryl group is preferable.

  Although the typical example of the anion represented by General formula (1) is shown below, it is not limited to these.

  Cesium salts, lithium salts and the like having these anions as counter ions can be easily obtained by salt exchange using, for example, sodium tetraphenylboron.

  As another counter anion preferable for the metal salt according to the present invention, an anion having a pyridine ring, a nitrogen-containing heterocycle such as a bipyridine ring or a terpyridine ring in the structure can be mentioned.

  Another preferred counter anion having a nitrogen-containing heterocycle includes an anion represented by any one of the above general formulas (2-1) to (2-5).

In the general formulas (2-1) to (2-5), R ₂₁ each independently represents a substituent, and the substituents may be bonded to form a ring. L ₁ represents a divalent linking group or a direct bond, and A ⁻ represents a substituent having an anion.

Examples of the substituent represented by R ₂₁ include an alkyl group (methyl group, ethyl group, i-propyl group, hydroxyethyl group, methoxymethyl group, trifluoromethyl group, t-butyl group, cyclopentyl group, cyclohexyl group, benzyl group). Group), aryl group (phenyl group, naphthyl group, p-tolyl group, p-chlorophenyl group, etc.), heteroaryl group (pyrrole group, imidazolyl group, pyrazolyl group, pyridyl group, benzimidazolyl group, benzothiazolyl group, benzooxa Zolyl group, triazolyl group, oxadiazolyl group, thiadiazolyl group, thienyl group, carbazolyl group, etc.), alkenyl group (vinyl group, propenyl group, styryl group etc.), alkynyl group (ethynyl group etc.), alkyloxy group (methoxy group, Ethoxy group, i-propoxy group, butoxy group, etc.), ants Ruoxy group (phenoxy group etc.), alkylthio group (methylthio group, ethylthio group, i-propylchio group etc.), arylthio group (phenylthio group etc.), amino group, alkylamino group (dimethylamino group, diethylamino group, ethylmethylamino group) Etc.), arylamino group (anilino group, diphenylamino group etc.), halogen atom (fluorine atom, chlorine atom, bromine atom, iodine atom etc.), cyano group, nitro group, non-aromatic heterocyclic group (pyrrolidyl group, Pyrazolyl group, imidazolyl group, etc.), silyl group (trimethylsilyl group, t-butyldimethylsilyl group, dimethylphenylsilyl group, triphenylsilyl group, etc.), etc., and each substituent further has a substituent. May be.

The divalent linking group represented by L ₁ represents a non-aromatic divalent linking group such as alkylene or alkenylene, or an aromatic divalent linking group. Of the non-aromatic divalent linking groups, for example, alkylene alkenylene, and the like, an alkylene group is preferable. These may be substituted, and examples include the groups mentioned as the substituent. Is an unsubstituted alkylene group such as methylene or ethylene. In addition, in these non-aromatic substituents, for example, groups such as alkylene, groups such as methylene or substituted methylene constituting the carbon atom forming the skeleton are substituted with hetero atoms such as oxygen atom, sulfur atom or nitrogen atom. It may have ether, thioether, or imino structure.

  Similarly, as the aromatic divalent substituent, in addition to a phenylene group, a biphenylene group, and the like, such an aromatic group is an alkylene group such as methylene and ethylene, and a methylene group that forms the skeleton is heterogeneous. It may be an alkylene group substituted with an atom, an alkylene group containing a thioether group or the like, or a group connected by an oxygen atom, a sulfur atom, a nitrogen atom or the like via an ether bond, a thioether bond, an imino group or the like.

In the general formulas (2-1) to (2-5), the substituent having an anion represented by A ⁻ is preferably a carboxylic acid group, a sulfonic acid group, a phosphoric acid group, and the like. A carboxylic acid group is preferred. n or m represents an integer of 5 or less, and in the general formula (2-1), m + n is an integer of 1 to 5, and m is at least 1. In the general formulas (2-2) to (2-4), m + n represents an integer of 1 to 4, and m is at least 1. In the general formula (2-5), m + n represents an integer of 1 to 3, and m is at least 1.

  Specific examples of anions having these nitrogen-containing aromatic heterocyclic structures as their partial structures include the following.

  As another preferred counter anion of the metal salt, there is an anion having a macrocyclic structure in its structure. As the anion having a macrocyclic structure in its structure, those represented by the general formula (3) are preferable.

In the general formula (3), each X independently represents an oxygen atom (—O—), a sulfur atom (—S—), or —N (—LA ^— ) —. the N-L-a ^- a. Here, L represents a divalent linking group or a direct bond. A ⁻ represents a substituent having an anion.

  The anions having a macrocyclic structure are more preferably those represented by the following general formulas (3-1) and (3-2).

In general formulas (3-1) and (3-2), n represents an integer of 3 or more, A ⁻ represents a substituent having an anion, and L ₂ represents a divalent linking group or a direct bond. To express.

  As described above, the divalent linking group and the substituent having an anion in the general formulas (3), (3-1), and (3-2) are the same as those in the general paper (2).

  Typical examples of these anions having a macrocyclic structure are shown below, but the present invention is not limited thereto.

  The metal salt according to the present invention shown above is mixed with, for example, an electron transporting compound to form a new mixed layer between the electron transport layer and the cathode or the cathode buffer layer, or a charge transport layer such as an electron transport layer. It can be contained in a transport layer or the like and can also serve as an electron transport layer. When a mixed layer is formed by doping an electron transport layer or another organic layer, it may be co-deposited with an organic material while adjusting the deposition rate according to the doping amount when the organic layer is formed. The doping amount (dopant concentration) of these metal salts is not particularly limited, but is preferably in the range of 0.1 to 99% by mass.

  If the concentration is less than 0.1% by mass, the dopant concentration is too low and the effect is small, and even if the concentration is too high, the concentration of the organic compound to be injected with charge is too low in the vicinity of the electrode, and the doping effect is rejected. It will go down.

  Moreover, it is preferable that the film thickness of the organic layer containing the metal salt of the present invention is at least 20 nm or more.

  The organic EL element of the present invention is an element having a structure in which an anode / organic layer / cathode is sequentially laminated on a substrate, and has an organic layer containing a metal salt between the electrode and the organic layer. For example, a mixed layer containing a metal salt and a charge transporting organic material is formed between the cathode and the organic layer. Of course, the cathode and anode may be reversed.

As a typical specific layer structure,
(I) Anode / light emitting layer / electron transport layer / cathode (ii) Anode / hole transport layer / light emitting layer / electron transport layer / cathode (iii) Anode / hole transport layer / light emitting layer / hole blocking layer / electron Transport layer / cathode (iv) anode / hole transport layer / light emitting layer / hole blocking layer / electron transport layer / cathode buffer layer / cathode (v) anode / anode buffer layer / hole transport layer / light emitting layer / hole Blocking layer / electron transport layer / cathode buffer layer / cathode, and the like. Here, the organic layer containing the metal salt according to the present invention includes, for example, a cathode or cathode buffer layer (electron injection layer) and an electron transport layer. The metal salt-containing layer may be provided between the organic layer and the electron-transporting layer or the electron-injecting layer.

  Hereinafter, the substrate and each layer will be described in detail.

<< About the organic layer containing a metal salt >>
In the present invention, the metal salt contained in the organic layer containing a metal salt (hereinafter also referred to as a mixed layer) is a salt having the anion of alkali metal or alkaline earth metal as a counter ion.

  As described above, lithium, cesium, sodium, calcium, and the like are preferable as the alkali metal or alkaline earth metal, and a salt composed of these metals and the counter ion is preferable.

  In the present invention, these metal salts lower the energy barrier during electron injection, while maintaining the concentration of the organic material responsible for electron transfer near the cathode and increasing the electron injection efficiency, as described above, in the mixed layer. As described above, the metal salt concentration is preferably 0.1 to 99.0% by mass, and more preferably 1.0 to 80.0% by mass.

  In particular, in the case of a cesium salt, the mass ratio with respect to the electron transporting organic material is preferably 0.1: 99.9 to 99: 1, and more preferably 1:99 to 80:20.

  Further, the thickness of the mixed layer is not particularly limited, but is preferably at least 20 nm or more and particularly preferably 20 nm to 80 nm in order to form a uniform film and reduce the driving voltage.

  The electron transporting organic material contained in the mixed layer may be any material that has a function of receiving electrons injected from the cathode and transporting the electrons. In addition to the mixed layer, an electron transporting layer or an electron injecting layer may be further provided.

  As an organic compound that can be used in the metal doping layer as an electron transporting organic material, known compounds can be used, and there are no particular limitations, but polycyclic compounds such as p-terphenyl and quaterphenyl and derivatives thereof, Condensed polycyclic hydrocarbon compounds such as naphthalene, tetracene, pyrene, coronene, chrysene, anthracene, diphenylanthracene, naphthacene, phenanthrene and their derivatives, phenanthroline, bathophenanthroline, phenanthridine, acridine, quinoline, quinoxaline, phenazine, etc. Heterocyclic compounds and their derivatives, fluorescein, perylene, phthaloperylene, naphthaloperylene, perinone, phthaloperinone, naphthaloperinone, diphenylbutadiene, tetraphenylbutadiene, oxadi Sol, aldazine, bisbenzoxazoline, bisstyryl, pyrazine, cyclopentadiene, oxine, aminoquinoline, imine, diphenylethylene, vinylanthracene, diaminocarbazole, pyran, thiopyran, polymethine, merocyanine, quinacridone, rubrene, and their derivatives, and also JP-A 63-295695, JP-A 8-22557, JP-A 8-81472, JP-A-5-9470, and JP-A-5-17764. Especially for metal chelated oxanoid compounds, tris (8-quinolinolato) aluminum, bis (8-quinolinolato) magnesium, bis [benzo (f) -8-quinolinolato] zinc, bis (2-methyl-8-quinolinolato) al Ni, tris (8-quinolinolato) indium, tris (5-methyl-8-quinolinolato) aluminum, 8-quinolinolatolithium, tris (5-chloro-8-quinolinolato) gallium, bis (5-chloro-8-quinolinolato) ) A metal complex having at least one 8-quinolinolato such as calcium or a derivative thereof as a ligand is preferably used.

  In addition, oxadiazoles disclosed in JP-A-5-202011, JP-A-7-179394, JP-A-7-278124, JP-A-7-228579, JP-A-7-157473 Triazines disclosed in JP-A-6-203963, stilbene derivatives and distyrylarylene derivatives disclosed in JP-A-6-203963, styryl derivatives disclosed in JP-A-6-132080 and JP-A-6-88072 The diolefin derivatives disclosed in JP-A-6-1000085 and JP-A-6-207170 are also preferred.

  Furthermore, compounds such as benzoxazole, benzothiazole, and benzimidazole can also be used, and examples thereof include those disclosed in JP-A-59-194393.

  In addition, for example, a distyrylbenzene compound disclosed in European Patent No. 0373582 and a distyrylpyrazine derivative disclosed in JP-A-2-252793 can also be used as the metal doping layer.

  In addition, 1,4-phenylenedimethylidin and 4,4 ′-(2,2-di-t-butylphenylvinyl) biphenyl disclosed in European Patent No. 388768 and JP-A-3-231970 are disclosed. Dimethylidin and biphenyl derivatives such as can be used as materials for the light-emitting layer, the electron transport layer, and the metal doping layer. Further, silanamine derivatives disclosed in JP-A-6-49079, JP-A-6-293778, polyfunctional styryl compounds disclosed in JP-A-6-279322, JP-A-6-279323, Anthracene compounds disclosed in JP-A-6-206865, oxynate derivatives disclosed in JP-A-6-145146, tetraphenylbutadiene compounds disclosed in JP-A-4-96990, JP-A-3 Organic trifunctional compounds disclosed in JP-A-296595, coumarin derivatives disclosed in JP-A-2-191694, perylene derivatives disclosed in JP-A-2-19685, and JP-A-2 Naphthalene derivatives disclosed in JP-A-255789, JP-A-2-28967 6 and phthaloperinone derivatives disclosed in JP-A-2-88689, and styrylamine derivatives disclosed in JP-A-2-250292.

  In addition, oxadiazole derivatives, triazole derivatives, oxazole derivatives, fluorenone derivatives, anthraquinodimethane derivatives, anthrone derivatives, diphenylquinone derivatives, thiols disclosed in JP-A-6-107648 and JP-A-6-92947 Metals having pyran dioxide derivatives, carbodiimide derivatives, fluorenylidenemethane derivatives, distyrylpyrazine derivatives, heterocyclic tetracarboxylic acid anhydrides such as naphthaleneperylene, phthalocyanine derivatives, metallophthalocyanines, benzoxazoles and benzothiazoles as ligands Conductive polymers such as complexes, aniline copolymers, thiophene oligomers, polythiophenes, polythiophene derivatives, polyphenylene derivatives, polyphenylene vinylene derivatives, polyfluorene derivatives, etc. It may be a known which are used in the production of conventional organic EL devices as appropriate.

  In addition to the metal salt according to the present invention, the organic layer containing the metal salt compound according to the present invention may be further doped with an alkali metal such as cesium or more than when the metal is doped alone. A stable doping effect can be obtained.

  Other constituent layers of the organic EL device of the present invention will be further described.

"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, a thin film may be formed by depositing these electrode materials 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 the pattern accuracy is not required (100 μm or more) Degree), a pattern may be formed through a mask having a desired shape when the electrode material is deposited or sputtered. When light emission is extracted from the anode, it is desirable that the transmittance is 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 nm to 1000 nm, preferably 10 nm 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, a mixture of an electron injecting metal and a second metal which is a stable metal having a larger work function value than this, such as a magnesium / silver mixture, magnesium, from the viewpoint of electron injectability and durability against oxidation, etc. / 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 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 with a film thickness of 1-20 nm on a cathode, a 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.

  Next, an injection layer, a blocking layer, an electron transport layer and the like used as a constituent layer 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, 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. You may let them.

  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 desirably 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>
In addition to the basic constituent layer of the organic compound thin film, it is provided as necessary. For example, as described in JP-A Nos. 11-204258 and 11-204359, and “Organic EL elements and the forefront of industrialization” (issued on November 30, 1998 by NTS Corporation). There is a hole blocking layer.

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

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

  In this invention, it is preferable to contain the compound which concerns on this invention mentioned above as a hole blocking material of a hole blocking layer. Thereby, it can be set as an organic EL element with much higher luminous efficiency. Furthermore, the lifetime can be further increased.

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

<Light emitting layer>
The light emitting layer contains a fluorescent compound and / or a phosphorescent compound, and light emission is extracted from the cathode or anode layer side. Specific examples of the compound used for each layer are described in, for example, “Monthly Display” October 1998 issue “Organic EL Display” (Techno Times).

  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.

  A known material can be used for the light emitting layer, and there is no particular limitation, but polycyclic compounds such as p-terphenyl and quaterphenyl and derivatives thereof, naphthalene, tetracene, pyrene, coronene, chrysene, anthracene, Condensed polycyclic hydrocarbon compounds such as diphenylanthracene, naphthacene, and phenanthrene and derivatives thereof; condensed heterocyclic compounds such as phenanthroline, bathophenanthroline, phenanthridine, acridine, quinoline, quinoxaline, and phenazine; and derivatives thereof. Fluorescein, perylene, phthaloperylene, naphthaloperylene, perinone, phthaloperinone, naphthaloperinone, diphenylbutadiene, tetraphenylbutadiene, oxadiazole, aldazine, bisbenzoxazoline, bisstyryl, pyrazine, cyclopentadiene, oxine, aminoquinoline, imine, diphenylethylene, Vinylanthracene, diaminocarbazole, pyran, thiopyran, polymethine, merocyanine, quinacridone, rubrene and the like, and derivatives thereof, and JP-A 63-295695, JP-A 8-22557, JP-A 8-81472, In the metal chelate complex compounds disclosed in JP-A-5-9470 and JP-A-5-17764, particularly metal chelated oxanoid compounds, (8-quinolinolato) aluminum, bis (8-quinolinolato) magnesium, bis [benzo (f) -8-quinolinolato] zinc, bis (2-methyl-8-quinolinolato) aluminum, tris (8-quinolinolato) indium, tris 8-quinolinolato or derivatives thereof such as (5-methyl-8-quinolinolato) aluminum, 8-quinolinolatolithium, tris (5-chloro-8-quinolinolato) gallium, bis (5-chloro-8-quinolinolato) calcium A metal complex having at least one ligand as a ligand is disclosed in JP-A-5-202011, JP-A-7-179394, JP-A-7-278124, and JP-A-7-228579. Oxadiazoles, disclosed in JP-A-7-157473 Triazines, stilbene derivatives and distyrylarylene derivatives disclosed in JP-A-6-203963, styryl derivatives disclosed in JP-A-6-132080 and JP-A-6-88072, and JP-A-6 The diolefin derivatives disclosed in JP-A No. 000085 and JP-A-6-207170 can be used in addition to compounds such as benzoxazole, benzothiazole, and benzimidazole, for example, JP-A-59-194393. The thing currently indicated by gazette gazette is mentioned.

  In addition, for example, a distyrylbenzene compound disclosed in European Patent No. 0373582 and a distyrylpyrazine derivative disclosed in JP-A-2-252793 can also be used as the metal doping layer. Further, 1,4-phenylenedimethylidin and 4,4 ′-(2,2-di-t-butylphenylvinyl) biphenyl disclosed in European Patent No. 388768 and JP-A-3-231970 are disclosed. Dimethylidin and biphenyl derivatives such as JP-A-6-49079, silanamine derivatives disclosed in JP-A-6-293778, JP-A-6-279322, and JP-A-6-279323. Polyfunctional styryl compounds, anthracene compounds disclosed in JP-A-6-206865, oxynate derivatives disclosed in JP-A-6-145146, and JP-A-4-96990 Tetraphenylbutadiene compound, organic trifunctionalization disclosed in JP-A-3-296595 And further, a coumarin derivative disclosed in JP-A-2-191694, a perylene derivative disclosed in JP-A-2-19685, a naphthalene derivative disclosed in JP-A-2-255789, Examples thereof include phthaloperinone derivatives disclosed in Kaihei 2-289676 and JP-A-2-88689, and styrylamine derivatives disclosed in JP-A-2-250292. In addition, oxadiazole derivatives, triazole derivatives, oxazole derivatives, fluorenone derivatives, anthraquinodimethane derivatives, anthrone derivatives, diphenylquinone derivatives, thiols disclosed in JP-A-6-107648 and JP-A-6-92947 Metals having pyran dioxide derivatives, carbodiimide derivatives, fluorenylidenemethane derivatives, distyrylpyrazine derivatives, heterocyclic tetracarboxylic acid anhydrides such as naphthaleneperylene, phthalocyanine derivatives, metallophthalocyanines, benzoxazoles and benzothiazoles as ligands Conductive polymers such as complexes, aniline copolymers, thiophene oligomers, polythiophenes, polythiophene derivatives, polyphenylene derivatives, polyphenylene vinylene derivatives, polyfluorene derivatives, etc. It may be a known which are used in the production of conventional organic EL devices as appropriate.

(Host compound)
However, the light emitting layer of the organic EL device of the present invention preferably contains a host compound and a phosphorescent compound (also referred to as a phosphorescent compound) shown below, and by using a phosphorescent compound. Further, the luminous efficiency can be further increased.

  In the present invention, the host compound is defined as a compound having a phosphorescence quantum yield of phosphorescence emission of less than 0.01 at room temperature (25 ° C.) among compounds contained in the light emitting layer.

  In the present invention, a plurality of known host compounds may be used in combination. 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. In addition, by using a plurality of phosphorescent compounds, it is possible to mix different light emission, thereby obtaining an arbitrary emission color. White light emission is possible by adjusting the kind of phosphorescent compound and the amount of doping, and can also be applied to illumination and backlight.

  As the host compound, a compound that has a hole transporting ability and an electron transporting ability, prevents the emission of light from being increased in wavelength, and has a high Tg (glass transition temperature) is preferable. Specific examples of the host compound used in the present invention include compounds described in the following documents.

  JP 2001-257076 A, JP 2002-308855 A, JP 2001-313179 A, 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.

  Moreover, the light emitting layer may contain the host compound which has a fluorescence maximum wavelength further as a host compound. In this case, the energy transfer from the other host compound and the phosphorescent compound to the fluorescent compound allows electroluminescence as an organic EL element to be emitted from the other host compound having a fluorescence maximum wavelength. A host compound having a fluorescence maximum wavelength is preferably a compound having a high fluorescence quantum yield in a solution state. Here, the fluorescence quantum yield is preferably 10% or more, particularly preferably 30% or more. Specific host compounds having a maximum fluorescence wavelength include coumarin dyes, pyran dyes, cyanine dyes, croconium dyes, squalium dyes, oxobenzanthracene dyes, fluorescein dyes, rhodamine dyes, and pyrylium dyes. Perylene dyes, stilbene dyes, polythiophene dyes, and the like. The fluorescence quantum yield can be measured by the method described in 362 (1992, Maruzen) of Spectroscopic II of the Fourth Edition Experimental Chemistry Course 7.

(Phosphorescent compound (phosphorescent compound))
The material used for the light emitting layer (hereinafter referred to as the light emitting material) preferably contains a phosphorescent compound at the same time as the host compound. Thereby, it can be set as an organic EL element with higher luminous efficiency.

  The phosphorescent compound according to the present invention is a compound in which light emission from an excited triplet is observed, is a compound that emits phosphorescence at room temperature (25 ° C.), and has a phosphorescence quantum yield of 0.2 at 25 ° C. 01 or more compounds. The phosphorescence quantum yield is preferably 0.1 or more.

  The phosphorescence quantum yield can be measured by the method described in Spectroscopic II, page 398 (1992 edition, Maruzen) of the Fourth Edition Experimental Chemistry Course 7. Although the phosphorescence quantum yield in a solution can be measured using various solvents, the phosphorescence quantum yield used in the present invention only needs to achieve the above phosphorescence quantum yield in any solvent.

  There are two types of light emission of phosphorescent compounds 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 phosphorescent. Energy transfer type to obtain light emission from the phosphorescent compound by transferring to the compound, the other is that the phosphorescent compound becomes a carrier trap, carrier recombination occurs on the phosphorescent compound, and from the phosphorescent compound In any case, 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 used in the present invention is preferably a complex compound containing at least one metal of Group 8 to Group 10 in the periodic table, more preferably an iridium compound, an osmium compound, or Platinum compounds (platinum complex compounds) and rare earth complexes, and most preferred are iridium compounds.

  Although the specific example of a phosphorescent compound is shown below, this invention is not limited to these. These compounds are described, for example, in Inorg. Chem. 40, 1704-1711, and the like.

  In the present invention, the phosphorescent maximum wavelength of the phosphorescent compound is not particularly limited. In principle, the phosphorescent compound can be obtained by selecting a central metal, a ligand, a ligand substituent, and the like. However, it is preferable that the phosphorescent compound has a maximum phosphorescence emission wavelength of 380 nm to 480 nm. With such a blue phosphorescent organic EL element and a white phosphorescent organic EL element, the luminous efficiency can be further increased.

  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 Minolta) is applied to the CIE chromaticity coordinates.

  The light emitting layer can be formed by forming the above compound 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. Although the film thickness as a light emitting layer does not have a restriction | limiting in particular, Usually, 5 nm-5 micrometers, Preferably it is chosen in the range of 5 nm-200 nm. The light emitting layer may have a single layer structure in which these phosphorescent compounds and host compounds are composed of one or more kinds, or may have a laminated structure composed of a plurality of layers having the same composition or different compositions. Good.

《Hole transport layer》
The hole transport layer is made of a 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.

  As the hole transport material according to the present invention, from the viewpoints of improving the external extraction quantum efficiency of the organic EL element, extending the emission lifetime, and the like, any one of the compounds represented by the general formulas (1) to (5) is provided. Preferably used.

  Further, a known hole transport material known in the art, a material commonly used as a hole charge injecting and transporting material, a known material used for a hole injecting layer and a hole transporting layer, etc. are used in combination. 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, Examples thereof include hydrazone derivatives, stilbene derivatives, silazane derivatives, aniline copolymers, and conductive polymer oligomers, particularly thiophene oligomers. Furthermore, a porphyrin compound, an aromatic tertiary amine compound, and a styrylamine compound, especially an aromatic tertiary amine compound can be used in combination.

  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 ' Di (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-diphenylaminostilbene; N-phenylcarbazole, as well as two described in US Pat. No. 5,061,569 Having a condensed aromatic ring of, for example, 4,4'-bis [N- (1-naphthyl) -N-phenylamino] biphenyl (NPD), JP-A-4-3086 4,4 ', 4 "-tris [N- (3-methylphenyl) -N-phenylamino] triphenylamine in which three triphenylamine units described in Japanese Patent No. 8 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.

  In the present invention, the hole transport material of the hole transport layer preferably has a fluorescence maximum wavelength at 415 nm or less. That is, the hole transport material is preferably a compound that has a hole transport ability, prevents the emission of light from becoming longer, and has a high Tg.

  Further, in the present invention, it is preferable that the phosphorescence 0-0 band of the hole transport material is 480 nm or less, so that it has higher emission luminance, excellent quantum efficiency, and even higher durability. In particular, it is to provide an organic electroluminescence element having a small luminance drop in the early stage of light emission, and a display device or illumination device comprising the same.

  A method for measuring the 0-0 band of the phosphorescence spectrum in the present invention will be described.

  First, a method for measuring a phosphorescence spectrum will be described.

  The compound to be measured was dissolved in a well-deoxygenated mixed solvent of ethanol / methanol = 4/1 (vol / vol), put into a phosphorescence measurement cell, and irradiated with excitation light at a liquid nitrogen temperature of 77 ° K. The emission spectrum at 100 ms after the excitation light irradiation is measured. Since phosphorescence has a longer emission lifetime than fluorescence, it can be considered that light remaining after 100 ms is almost phosphorescence.

  For compounds with a phosphorescence lifetime shorter than 100 ms, measurement may be performed with a shorter delay time, but phosphorescence and fluorescence cannot be separated if the delay time is shortened so that it cannot be distinguished from fluorescence. Since this is a problem, it is necessary to select a delay time that can be separated.

  In addition, for a compound that cannot be dissolved in the solvent system, any solvent that can dissolve the compound may be used (substantially, the solvent effect of the phosphorescence wavelength is negligible in the above measurement method).

  Next, the 0-0 band is determined. In the present invention, the emission maximum wavelength that appears on the shortest wavelength side in the phosphorescence spectrum chart obtained by the above-described measurement method is defined as the 0-0 band.

  Since the phosphorescence spectrum usually has a low intensity, when it is enlarged, it may be difficult to distinguish between noise and peak. In such a case, the steady light spectrum is enlarged, and the peak wavelength is read from the portion of the steady light spectrum derived from the phosphorescence spectrum by superimposing it with the emission spectrum 100 ms after irradiation with the excitation light (for convenience, this is called the phosphorescence spectrum). Can be determined. Further, by performing a smoothing process on the phosphorescence spectrum, it is possible to separate the noise and the peak and read the peak wavelength. As the smoothing process, a smoothing method of Savitzky & Golay can be applied.

  The hole transport layer is formed by thinning the hole transport material by a known method such as a vacuum deposition method, a spin coating method, a casting method, an ink jet method, an LB method, a transfer method, or a printing method. be able to. Although there is no restriction | limiting in particular about the film thickness of a positive hole transport layer, Usually, it is about 5-5000 nm. The hole transport layer may have a single layer structure composed of one or more of the above materials.

《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.

  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), 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 similarly to the hole injection layer and the hole transport layer, inorganic such as n-type-Si and n-type-SiC can be used. A semiconductor can also be 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 nm-200 nm. The electron transport layer may have a single layer structure composed of one or more of the above materials.

<Diffusion prevention layer>
The anti-diffusion layer according to the present invention is an organic material (for example, an electron transport material, an electron donating material) that constitutes an EL element that causes a decrease in light emission efficiency or a light emission lifetime of the EL element. Compound), inorganic materials (for example, metals, salts of the metal, etc.), or contaminants in the organic / inorganic materials diffuse into the light emitting layer (from adjacent layers) or diffuse in the light emitting layer It has a role to prevent. As long as it has such a role, it may be combined with other layers such as an anode buffer layer, a hole transport layer, a light emitting layer, a hole blocking layer, an electron transport layer, and a cathode buffer layer.

  In order to obtain the maximum effect of the present invention, it is preferable to prevent or suppress the diffusion of ions in the metal salt contained in the charge transport material, for example, the electron transport material-containing layer.

  The diffusion preventing layer (including the case where it also serves as another layer) is preferably located between the light emitting layer and the cathode or the anode, and is further located between the cathode or cathode buffer layer and the light emitting layer. More preferably, it has a position adjacent to the cathode or cathode buffer layer.

  The material used for the formation of the diffusion prevention layer according to the present invention is a compound used for a conventionally known metal ion trap or the like (for example, a crown ether compound), a compound capable of inclusion of a metal or a metal ion, or a metal coordination Any coordinating organic compound that can be used can be used. Here, the inclusion compound is, for example, a compound described in “Supramolecular Science: edited by Naotoshi Nakajima; published by Doujin Kagaku; published in March 2004” and literatures cited as references in the book. Can be used.

<Substrate>
The organic EL device of the present invention is preferably formed on a substrate. The substrate (hereinafter also referred to as a substrate, substrate, support, etc.) that can be used in the organic EL device of the present invention is not particularly limited in the type of glass, plastic, etc. Although there is no restriction | limiting in particular, As a board | substrate used preferably, glass, quartz, and a transparent resin film can be mentioned, for example. A particularly preferable substrate is a resin film that can give flexibility to the organic EL element.

  Examples of the resin film include polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polyetherimide, polyetheretherketone, polyphenylene sulfide, polyarylate, polyimide, polycarbonate (PC), and cellulose. Examples include films made of triacetate (TAC), cellulose acetate propionate (CAP), 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.

  The external extraction efficiency at room temperature for light emission of the organic electroluminescence 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.

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

  First, a thin film made of a desired electrode material, for example, an anode material is formed on a suitable substrate by a method such as vapor deposition or sputtering so as to have a film thickness of 1 μm or less, preferably 10 nm to 200 nm. Make it. Next, a hole injection layer, a hole transport layer, a light emitting layer, a hole blocking layer, an electron transport layer, a mixed layer according to the present invention, and an organic compound thin film, which are organic EL element materials, are formed thereon.

As a method for thinning the organic compound thin film, there are a vapor deposition method and a wet process (for example, a spin coating method, a casting method, an ink jet method, a printing method) as described above. From the standpoint that pinholes are hardly generated, vacuum deposition, spin coating, ink jet, and printing are preferred. Particularly preferred is a vacuum deposition method. Further, a different film forming method may be applied for each layer. When a vapor deposition method is employed for film formation, the vapor deposition conditions vary depending on the type of compound used, but generally a boat heating temperature of 50 ° C. to 450 ° C., a vacuum degree of 10 ⁻⁶ Pa to 10 ⁻² Pa, and a vapor deposition rate of 0 It is desirable to select appropriately within the range of 0.01 nm / second to 50 nm / second, substrate temperature −50 ° C. to 300 ° C., film thickness 0.1 nm to 5 μm, preferably 5 nm to 200 nm.

  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, and a cathode is provided. Thus, a desired organic EL element can be obtained. The organic EL element 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.

  The multi-color display device of the present invention is provided with a shadow mask only at the time of forming a light emitting layer, and other layers are common, so patterning such as a shadow mask is unnecessary, and vapor deposition, casting, spin coating, inkjet A film can be formed by a method or a printing method.

  When patterning is performed only on the light-emitting layer, the method is not limited, but a vapor deposition method, an inkjet method, and a printing method are preferable. In the case of using a vapor deposition method, patterning using a shadow mask is preferable.

  In addition, the order of preparation can be reversed, and the cathode, mixed layer, electron transport layer, hole blocking layer, light emitting layer, hole transport layer, hole injection layer, and anode can be formed in this order. When a DC voltage is applied to the multicolor display device thus obtained, 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. An alternating voltage may be applied. The alternating current waveform to be applied may be arbitrary.

  Conventionally, an active type organic EL has a bottom emission structure in which light is extracted from the substrate side having a TFT drive circuit, and therefore, the ratio of the light emitting area is reduced, which is one of the causes of lowering the light emitting efficiency. A top emission structure in which light is extracted from the side is preferable.

  In this case, according to a predetermined pattern, for example, Al is deposited by vapor deposition so that the film thickness is 1 μm or less, preferably in the range of 50 to 200 nm, and the cathode is formed. Then, the mixed layer, the electron transport layer The organic EL layers such as the light emitting layer and the like are formed in the same manner as described above, and the anode is formed in the range of 50 to 200 nm by DC magnetron sputtering using an ITO target, for example.

  Moreover, inexpensive amorphous silicon can be used for the drive circuit by top emission, which may contribute to the cost reduction of the organic EL.

  The display device of the present invention 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 the display include a television, a personal computer, a mobile device, an AV device, a character broadcast display, and an information display in a car. 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.

  Illumination devices 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. However, it is not limited to these. Moreover, you may use as an organic EL element which gave the organic EL element of this invention the resonator structure.

  Examples of the purpose of use of the organic EL element having such a resonator structure include a light source of an optical storage medium, a light source of an electrophotographic copying machine, a light source of an optical communication processing machine, and a light source of an optical sensor. It is not limited. Moreover, you may use for the said use by making a laser oscillation.

  The organic EL material used in the present invention can be applied to an organic EL element that emits substantially white light as a lighting device. 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 three primary colors of blue, green, and blue, or two using a complementary color relationship 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 that emit light, and a light emitting material that emits fluorescence or phosphorescence, and light from the light emitting material. Any combination with a dye material that emits light as excitation light may be used. However, in the white organic electroluminescence device according to the present invention, it is only necessary to mix and combine a plurality of light-emitting dopants. It is only necessary to provide a mask only when forming a light emitting layer, a hole transport layer, an electron transport layer, or the like, and simply arrange them separately by 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, an ortho metalated complex (Ir complex, so that it may suit the wavelength range corresponding to CF (color filter) characteristic) Pt complex etc.) or any known light emitting material may be selected and combined to whiten.

  Thus, in addition to the display device and display, the white light-emitting organic EL element according to the present invention can be used as various light-emitting light sources and lighting devices as a kind of lamp such as home lighting, interior lighting, and exposure light source. It is also useful for display devices such as backlights for liquid crystal display devices.

  Others such as backlights for watches, signboard 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. There are a wide range of uses such as household appliances.

<Display device>
The organic EL element of the present invention may be used as one 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). When used as a display device for reproducing moving images, the driving method 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 three or more organic EL elements of the present invention having different emission colors. Alternatively, it is possible to make a single color emission color, for example, white emission, into BGR using a color filter to achieve full color. Furthermore, it is possible to convert the emission color of the organic EL to another color by using a color conversion filter, and in this case, λmax of the organic EL emission is preferably 480 nm or less.

  In such applications, the organic EL element has poor energy efficiency of blue light emission. Therefore, the effect of lowering the driving potential by containing the metal salt according to the present invention in the organic layer is therefore at least a blue component. It is particularly preferable in an organic EL device containing.

  An example of a display device composed of the organic EL element of the present invention will be described with reference to the drawings.

  FIG. 1 is a schematic diagram illustrating an example of a display device including 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 the plurality of pixels based on image information from the outside. The pixels for each scanning line are converted into image data signals by the scanning signal. In response to this, light is sequentially emitted and image scanning is performed to display 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. FIG. 2 shows a case where the light emitted from the pixel 3 is extracted in the direction of the white arrow (downward).

  The scanning lines 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 orthogonal positions (details are shown in FIG. Not shown).

  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 that emit light on the same substrate.

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

  FIG. 3 is a schematic diagram showing a circuit 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. 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 organic EL element 10 emits light by the switching transistor 11 and the drive transistor 12 that are active elements for the organic EL element 10 of each of the plurality of pixels, and the light emission of the organic EL element 10 of each of the plurality of pixels 3. 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 on / off of a predetermined light emission amount by a binary image data signal. But you can.

  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 view 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 pixel 3 connected to the applied scanning line 5 emits 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.

  EXAMPLES The present invention will be specifically described below with reference to examples, but the present invention is not limited thereto.

Example 1
Transparent support provided with this ITO transparent electrode after patterning on a substrate (NH45 manufactured by NH Techno Glass) made of ITO (indium tin oxide) with a thickness of 100 nm on a glass substrate of 100 mm × 100 mm × 1.1 mm as an anode The substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes. This transparent support substrate was fixed to a substrate holder of a commercially available vacuum deposition apparatus.

  This transparent support substrate was fixed to a substrate holder of a commercially available vacuum deposition apparatus. However, CuPc (copper phthalocyanine), α-NPD, CBP, Ir-1, B-Alq, BPhen, and a compound 1-1Cs salt were each filled in an optimum amount for device fabrication in each vapor deposition boat in the vapor deposition apparatus. The vapor deposition boat used was made of a molybdenum resistance heating material.

Next, after reducing the pressure of the vacuum chamber to 4 × 10 ⁻⁴ Pa, the deposition boat containing CuPc (copper phthalocyanine) was energized and heated to deposit 20 nm on the transparent support substrate at a deposition rate of 0.1 nm / second. The hole injection layer was provided.

  Next, the evaporation boat containing α-NPD was energized, α-NPD was evaporated at a rate of 0.1 nm / second, and a hole transport layer was formed to 20 nm. Further, the heating boats containing CBP and Ir-1 are energized and heated, and are co-deposited on the hole transport layer at a deposition rate of 0.2 nm / second and 0.012 nm / second, respectively, to form a light emitting layer. 30 nm. In addition, the substrate temperature at the time of vapor deposition was room temperature. Furthermore, BAlq was vapor-deposited on the light emitting layer at a vapor deposition rate of 0.1 nm / sec to provide an electron transport layer having a thickness of 10 nm that also serves as a hole blocking function. Furthermore, BPhen and the compound 1-1Cs salt were further vapor-deposited at 0.1 nm / second and 0.025 nm / second to provide an electron transport layer with a thickness of 50 nm.

  Subsequently, 110 nm of aluminum was deposited to form a cathode, and an organic EL device 1-1 was produced.

  In the production of the organic EL element 1-1, the organic EL element was manufactured in the same manner as the organic EL element 1-1 except that the charge transport material BPhen and the compound 1-1Cs salt co-deposited therewith were changed to the materials shown in Table 1. 1-2 to 1-21 were produced. In the table, the mixing ratio is shown as a deposition rate ratio.

  The structure of the compound used above is shown below.

  Since cesium salts are deliquescent, for each metal salt, an evaporation source was set in a vacuum chamber and then vacuumed, and the evaporation source was heated once before evaporation to remove moisture. . Incidentally, when this procedure was not performed and moisture was not completely removed, the performance of the organic EL deteriorated.

  The lifetime of the organic EL elements 1-1 to 1-21 and the evaluation of the drive voltage were performed by the following methods.

<Drive voltage>
Measure the voltage when driven at a constant current of ^2.5 mA / cm ² ,
Voltage evaluation value = drive voltage of organic EL elements 1-1 to 1-20 / drive voltage of organic EL element 1-4 × 100
Expressed in A smaller value indicates a lower drive voltage for comparison.

<Preservability>
The storability was evaluated by looking at how much the luminance in the ^2.5 mA / cm ² constant current drive changed before and after storage at 85 ° C. for 100 hours.

Storage stability = luminance after 100 hours storage / luminance before 100 hours storage × 100
The organic EL element configuration and evaluation results are shown below.

  Compared to the organic EL element 1-21 (comparative example) having an electron transport layer in which LiF described in JP-A-10-270172 and JP-A-2004-193011 is co-deposited together with BPhen, the driving voltage is set in the present invention. It can be seen that the organic EL elements 1-1 to 1-20 are not inferior, and even when stored at 85 ° C. for 100 hours, when driven at a constant current, the decrease in luminance is less than that of the comparative example.

Example 2
Transparent support provided with this ITO transparent electrode after patterning on a substrate (NH45 manufactured by NH Techno Glass) made of ITO (indium tin oxide) with a thickness of 100 nm on a glass substrate of 100 mm × 100 mm × 1.1 mm as an anode The substrate was ultrasonically cleaned with isopropyl alcohol, dried with dry nitrogen gas, and subjected to UV ozone cleaning for 5 minutes. This transparent support substrate was fixed to a substrate holder of a commercially available vacuum deposition apparatus.

Next, after reducing the vacuum chamber to 4 × 10 ⁻⁴ Pa, m-MTDATA and F4-TCNQ were co-deposited on the transparent support substrate at a deposition rate of 0.2 nm / second and 0.002 nm / second, respectively, to form holes. An injection layer was provided. Next, m-MTDATXA was deposited at 0.1 nm / second to provide a hole transport layer. On top of that, the heating boat containing CDBP and Ir-14 is energized and heated, and co-evaporated on the hole transport layer at a deposition rate of 0.1 nm / second and 0.003 nm / second, respectively, to form a light emitting layer. 30 nm was provided. In addition, the substrate temperature at the time of vapor deposition was room temperature. Furthermore, HB-1 was vapor-deposited on the light emitting layer at a vapor deposition rate of 0.1 nm / sec to provide an electron transport layer having a thickness of 10 nm and also serving as a hole blocking function. Further thereon, N-1 was provided as a diffusion preventing layer at a thickness of 10 nm at a deposition rate of 0.1 nm / second.

  On the diffusion prevention layer, the charge transport material N-1 and the compound 1-1Cs salt were deposited at a deposition rate of 0.1 nm / second and 0.025 nm / second, respectively, to provide an electron transport layer (film thickness 50 nm). .

  Subsequently, 110 nm of aluminum was deposited to form a cathode, and an organic EL element 2-1 was produced.

  In the production of the organic EL element 2-1, an element without a diffusion preventing layer was designated as an organic EL element 2-2.

  Table 2 shows the results of evaluating the storage stability of the organic EL elements 2-1 and 2-2.

The storability was evaluated by how much the luminance at a constant current drive of ^2.5 mA / cm ² changed before and after storing the organic EL device produced at 85 ° C. for 100 hours.

  Storage stability = luminance after 100 hours storage / luminance before 100 hours storage × 100

  The organic EL element 2-1 provided with the diffusion preventing layer has further improved storage stability compared to the organic EL element 2-2 without the first embodiment.

  This is presumably because the diffusion of cesium ions from the electron transport layer to the light emitting layer is prevented.

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 which shows the circuit of a pixel. It is a schematic diagram of the display apparatus by a passive matrix system.

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

Claims (23)

An organic electroluminescence device having an anode, a cathode and at least one organic layer on a substrate, wherein one layer of the organic layer contains a metal salt. The organic electroluminescence device according to claim 1, wherein the organic layer containing the metal salt is adjacent to a cathode. The organic electroluminescence device according to claim 2, wherein the organic layer containing the metal salt further contains a metal atom. The organic electroluminescence device according to claim 2, wherein the thickness of the organic layer containing the metal salt is at least 20 nm or more. The organic electroluminescent element according to claim 1, wherein the metal salt is a sulfate. The organic electroluminescence device according to claim 1, wherein the metal salt is a salt of a carboxylic acid containing fluorine. The organic electroluminescence device according to claim 1, wherein the counter anion of the metal salt is SCN ⁻ or NCS ⁻ . The organic electroluminescence device according to any one of claims 1 to 4, wherein the counter anion of the metal salt is represented by the following general formula (1).

[Wherein, R _{1 to} R ₄ each independently represents a substituent. ] The organic electroluminescence device according to any one of claims 1 to 4, wherein the counter anion of the metal salt is an anion having a pyridine ring, a bipyridine ring, or a terpyridine ring. 5. The organic electroluminescence device according to claim 1, wherein the counter anion of the metal salt is represented by any one of the following general formulas (2-1) to (2-5). .

[Wherein, R ₂₁ each independently represents a substituent, and the substituents may be bonded to form a ring. L ₁ represents a divalent linking group or a direct bond, and A ⁻ represents a substituent having an anion. n or m represents an integer of 5 or less, and in the general formula (2-1), m + n is an integer of 1 to 5, and m is at least 1. In the general formulas (2-2) to (2-4), m + n represents an integer of 1 to 4, and m is at least 1. In the general formula (2-5), m + n represents an integer of 1 to 3, and m is at least 1. ] The organic electroluminescence device according to claim 1, wherein the counter anion of the metal salt is an anion having a macrocyclic structure. The organic electroluminescence device according to claim 11, wherein the anion having a macrocyclic structure is represented by the following general formula (3).

[In the formula, n represents an integer of 3 or more, and X independently represents an oxygen atom (—O—), a sulfur atom (—S—), —N (—LA ^— ) — at least one of X is N-L-a ^- a. Here, L represents a divalent linking group or a direct bond, and A ⁻ represents a substituent having an anion. ] The organic electroluminescence device according to any one of claims 1 to 12, wherein the metal salt is an alkali metal salt or an alkaline earth metal salt. The organic electroluminescent element according to claim 1, wherein the metal salt is a lithium salt. The organic electroluminescent element according to claim 1, wherein the metal salt is a cesium salt. The organic electroluminescent element according to claim 1, wherein the metal salt is a sodium salt. The organic electroluminescence device according to any one of claims 1 to 12, wherein the metal salt is a calcium salt. The organic electroluminescence device according to claim 1, further comprising a diffusion prevention layer that suppresses diffusion of metal ions constituting the metal salt. The organic electroluminescent element according to claim 1, wherein the light emission includes light emission based on phosphorescence emission. The organic electroluminescence device according to claim 1, wherein the light emission includes at least a blue component. The organic electroluminescence device according to any one of claims 1 to 20, wherein emitted light is extracted from a direction opposite to the substrate. The organic electroluminescence device according to any one of claims 1 to 21, wherein the anode, the cathode, and the organic layer are manufactured by a vapor deposition method. 23. The organic electroluminescent device according to claim 1, wherein the metal salt is preheated before vapor deposition when the metal salt is vapor-deposited. Manufacturing method.

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