Organometallic complexes and organic light-emitting devices, display devices, imaging devices, electronic devices, lighting devices, and moving bodies each containing the same

Abstract

The present invention provides an organometallic complex, characterized in that it is represented by the general formula (1). In the general formula (1), M represents a metal atom and is selected from Ir, Pt, Os, Rh, Pd and Ru; R 1 to R 8 Each independently represents a hydrogen atom and a substituent, wherein R 1 to R 8 At least one of represents a substituent; and R 9 and R 10 At least one of the groups represents an alkyl group having 2 or less carbon atoms. #imgabs0#

Description

Technical Field

[0001] The present invention relates to an organic metal complex, and an organic light-emitting device, a display device, an imaging device, an electronic device, a lighting device, and a mobile object including the organic metal complex. Background Art

[0002] An organic light-emitting device (OLED) is an electronic device that includes a first electrode, a second electrode, and an organic compound layer disposed between these electrodes. Electrons and holes are injected from this pair of electrodes into the organic compound layer to generate excitons in the light-emitting organic compound in the organic compound layer. When these excitons return to a ground state, the OLED emits light. OLEDs are also called organic electroluminescent devices or organic EL devices.

[0003] Light-emitting organic compounds can be broadly divided into two types based on their emission mechanism: fluorescent materials and phosphorescent materials. In the generation of excitons within organic light-emitting devices, phosphorescent materials are known to exhibit higher luminescence efficiency than fluorescent materials due to the principles of quantum mechanics. Specifically, the organometallic complex Ir(ppy)3 represented by the following structure is considered a green phosphorescent material.

[0004]

[0005] New materials for organic light-emitting devices are being developed to improve, for example, driving voltage, luminous quantum yield, color gamut, and device life. Patent document 1 describes the following compound A as a compound for a light-emitting device that maintains high brightness for a long time and has little degradation due to power-on. Patent document 2 describes an organic metal complex having a ligand with the same structure as compound A as a compound that emits phosphorescence. Patent document 3 describes a material having an alkyl or cycloalkyl group with 3 to 10 carbon atoms at position 1 of dibenzofuran in the ligand to improve the life or efficiency of the organic light-emitting device. As specific examples, compounds B and C are described below. Patent document 4 describes compound D as a complex for improving efficiency, operating voltage, life, and color coordinates.

[0006]

[0007] Prior art literature

[0008] Patent Literature

[0009] Patent Document 1: Japanese Patent Laid-Open No. 2002-332291

[0010] Patent Document 2: U.S. Patent Application Publication No. 2018 / 0282356

[0011] Patent Document 3: International Publication No. 2019 / 221484

[0012] Patent Document 4: International Publication No. 2014 / 023377 Summary of the Invention

[0013] Problems to be solved by the invention

[0014] Organic light-emitting devices (OLEDs) are known to experience a phenomenon known as roll-off, whereby luminous efficiency decreases at high current densities. The organometallic complexes described in Patent Documents 1 to 4 have room for improvement in terms of a decrease in luminous efficiency at a second current density higher than the first current density (i.e., the so-called roll-off characteristic), based on the luminous efficiency at a first current density.

[0015] Solutions for solving problems

[0016] The present invention has been made in view of the above problems, and an object of the present invention is to provide an organic metal complex having a reduced rate of decrease in luminous efficiency at a second current density higher than the first current density relative to the luminous efficiency at a first current density.

[0017] The present invention provides an organometallic complex represented by the following general formula (1).

[0018]

[0019] In the general formula (1), M is a metal atom selected from Ir, Pt, Os, Rh, Pd and Ru. 1 to R 8 Each is independently selected from a hydrogen atom and a substituent. The substituent is a halogen atom, a cyano group, a nitro group, a trialkylsilyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, or a substituted or unsubstituted aryl group having two or fewer rings. 9 and R 10 are each independently selected from a hydrogen atom and an alkyl group having 2 or less carbon atoms. 1 to R 8 At least one of them is a substituent, or R 9 and R 10 At least one of them is an alkyl group having 2 or less carbon atoms.

[0020] Effects of the Invention

[0021] According to the present invention, an organic metal complex can be provided in which the decrease rate of the luminous efficiency at a second current density higher than the first current density is reduced relative to the luminous efficiency at a first current density. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1A is a schematic cross-sectional view of an example of a pixel of a display device according to an embodiment of the present invention.

[0023] Figure 1B is a schematic cross-sectional view of an example of a display apparatus including an organic light-emitting device according to an embodiment of the present invention.

[0024] Figure 2 is a schematic diagram of an example of a display apparatus including an organic light emitting device according to an embodiment of the present invention.

[0025] Figure 3A is a schematic diagram of an example of an image pickup apparatus according to an embodiment of the present invention.

[0026] Figure 3B is a schematic diagram of an example of an electronic device according to an embodiment of the present invention.

[0027] Figure 4A is a schematic diagram of an example of a display device according to an embodiment of the present invention.

[0028] Figure 4B is a schematic diagram of an example of a foldable display device.

[0029] Figure 5A is a schematic diagram of an example of a lighting device according to an embodiment of the present invention.

[0030] Figure 5B 1 is a schematic diagram of a car as an example of a moving object according to an embodiment of the present invention.

[0031] Figure 6A FIG. 1 is a schematic diagram illustrating an example of a wearable device according to an embodiment of the present invention.

[0032] Figure 6B FIG. 2 is a schematic diagram of an example of a wearable device according to an embodiment of the present invention, wherein the wearable device includes a camera. DETAILED DESCRIPTION

[0033] The following describes embodiments of the present invention. The present invention is not limited to the following description, and those skilled in the art will readily appreciate that various changes in form and details may be made without departing from the spirit and scope of the present invention. That is, the present invention should not be construed as being limited to the following description.

[0034] [Organometallic complex represented by general formula (1)]

[0035] The present inventors have conducted studies and found an organometallic complex that can reduce the decrease in luminous efficiency even at a high current density, and is represented by the following general formula (1).

[0036]

[0037] In the general formula (1), M is a metal atom selected from Ir, Pt, Os, Rh, Pd and Ru. 1 to R 8 Each is independently selected from a hydrogen atom and a substituent. The substituent is a halogen atom, a cyano group, a nitro group, a trialkylsilyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, and a substituted or unsubstituted aryl group having two or fewer rings.

[0038] R 9 and R 10 Each is independently selected from a hydrogen atom and an alkyl group having 2 or less carbon atoms.

[0039] However, R 1 to R 8 At least one of them is a substituent, or R 9 and R 10 At least one of them is an alkyl group having 2 or less carbon atoms.

[0040] In the present specification, M is a metal atom forming a complex, and specific examples thereof include Ir, Pt, Os, Rh, Pd, Ru, and Re. Among these, Ir is preferred.

[0041] In this manual, R 1 to R 8 The halogen atom is any one of a fluorine atom, a chlorine atom, a bromine atom and an iodine atom. Among these, a fluorine atom is preferred from the viewpoint of thermal stability.

[0042] In this specification, R 1 to R 8 The alkyl group in the trialkylsilyl group may be an alkyl group having an independent number of carbon atoms. The alkyl group is preferably an alkyl group having 1 to 8 carbon atoms and may be a linear alkyl group or a branched alkyl group. More specific examples include, but are not limited to, a trimethylsilyl group, a tert-butyldimethylsilyl group, and a triisopropylsilyl group.

[0043] In this manual, R 1 to R 8 Each alkyl group of may be a linear alkyl group or a branched alkyl group. The alkyl group may have 1 to 20 carbon atoms, and may have 1 to 8 carbon atoms.

[0044] In this manual, R 1 to R 8 and R11 to R 18 Each cycloalkyl group may have 3 to 20 carbon atoms, and may have 3 to 10 carbon atoms. The cycloalkyl group is preferably a cyclohexyl group or a cyclopentyl group. The carbon atoms of the cycloalkyl group may be substituted with oxygen atoms, but it is not preferred to replace two consecutive carbon atoms with oxygen atoms. One carbon atom may be replaced with an oxygen atom.

[0045] In the present specification, examples of the aryl group having two or fewer rings include phenyl, naphthyl, pyridyl, benzothienyl, benzofuranyl, benzoxazolyl, quinolyl, and isoquinolyl, preferably phenyl.

[0046] In the present specification, examples of the aryl group include a phenyl group, a naphthyl group, a biphenyl group, a fluorenyl group, a phenanthryl group, an anthracenyl group, a pyridyl group, a carbazolyl group, a dibenzofuranyl group, and a dibenzothiophenyl group.

[0047] In this specification, the alkyl group or cycloalkyl group may further have a substituent. Examples of substituents include halogen atoms, cyano groups and nitro groups. The halogen atoms that can be substituted on the alkyl group are any one of fluorine atoms, chlorine atoms, bromine atoms and iodine atoms. Among these, fluorine atoms are preferred from the perspective of thermal stability. In the alkyl group or cycloalkyl group, one methylene group or two or more non-adjacent methylene groups may be substituted by -O-, -S-, -C(=O)-, -C(=O)O-, -O(C=O)-, -CH=CH- or -C≡C- groups, and hydrogen atoms may be substituted by fluorine atoms.

[0048] In the present specification, an aryl group may have an alkyl group as a substituent. In the alkyl group, one methylene group or two or more non-adjacent methylene groups may be substituted by an -O- group, an -S- group, a -C(=O)- group, a -C(=O)O- group, a -O(C=O)- group, a -CH=CH- group, or a -C≡C- group, and a hydrogen atom may be substituted by a fluorine atom.

[0049] Specific examples of the aryl group (including an aryl group further having a substituent) in the present specification include, but are not limited to, phenyl, 1-naphthyl, 2-naphthyl, 4-biphenyl, 2-fluorenyl, 9-phenanthrenyl, 2-anthryl, 1-pyrenyl, 1-imidazolyl, 2-furyl, 3-benzofuranyl, 4-dibenzofuranyl, 2-thienyl, 3-benzothienyl, 2-dibenzothienyl, 2-pyridyl, 2-pyrimidyl , 1-indolyl, 2-indolyl, 9-carbazolyl, p-chlorophenyl, o-tolyl, 4-methoxyphenyl, 4'-(1-hexynyl)phenyl, 2-(1-(1,1,2,2,3,3,4,4,5,5,6,6,7,7,8,8-hexafluoro)octyloxycarbonyl)phenyl, 4'-cyanobiphenyl, 2-(9,9-dimethyl)fluorenyl, and 3-(9,9-dioctyl)fluorenyl.

[0050] R9 and R 10 Each is independently selected from a hydrogen atom and an alkyl group having 2 or less carbon atoms. Specifically, each of them is a hydrogen atom, a methyl group or an ethyl group.

[0051] In the organometallic complex according to the present invention, R 1 to R 8 At least one of the substituents is any one of the above substituents, or R 9 and R 10 At least one of the groups is an alkyl group having two or fewer carbon atoms. Therefore, the organometallic complex according to the present invention has the effect of reducing the decrease in luminous efficiency at high current density. In other words, the organometallic complex has excellent attenuation characteristics.

[0052] When R 1 to R 8 When at least one of R is a substituent, 9 and R 10 Both may be hydrogen atoms.

[0053] R 1 to R 4 Can be independently selected from hydrogen atoms and the above alkyl groups. 3 For tert-butyl.

[0054] R 5 to R 8 They may each be independently selected from a hydrogen atom and the above-mentioned alkyl groups.

[0055] In the general formula (1), R 3 In the case of , an aryl group can be used without being limited to two or fewer rings. That is, the general formula (1) can be within the following range.

[0056] R 1 、R 2 、R 4 to R 8 Each is independently selected from a hydrogen atom and a substituent. The substituent is a halogen atom, a cyano group, a nitro group, a trialkylsilyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, or a substituted or unsubstituted phenyl group. 3 R is selected from a hydrogen atom, a halogen atom, a cyano group, a nitro group, a trialkylsilyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, and a substituted or unsubstituted aryl group. 9 and R 10 are each independently selected from a hydrogen atom and an alkyl group having 2 or less carbon atoms. 1 to R 8 is not a hydrogen atom, or R 9 and R 10 At least one of them is an alkyl group having 2 or less carbon atoms.

[0057] When R in the general formula (1) 9 and R 10 When at least one of the groups is an alkyl group having 2 or less carbon atoms, for R 1 to R 8 , aryl groups can be used without being limited to 2 or fewer rings. 9 and R 10 When any one of them is an alkyl group having 2 or less carbon atoms, R 9 An alkyl group having 2 or less carbon atoms is preferred. That is, the general formula (1) may be within the following range.

[0058] R 1 to R 8 Each is independently selected from a hydrogen atom and a substituent. The substituent is a halogen atom, a cyano group, a nitro group, a trialkylsilyl group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted cycloalkyl group, and a substituted or unsubstituted aryl group. 9 and R 10 are each independently selected from a hydrogen atom and an alkyl group having 2 or less carbon atoms. 9 and R 10 At least one of them is an alkyl group having 2 or less carbon atoms.

[0059] Specific examples of the structural formula of the organometallic complex of the present invention are shown below. Iridium complexes are given as examples, but the same applies when other metals are used. The number of ligands can be varied depending on the coordination number of the metal.

[0060]

[0061]

[0062]

[0063] Among the exemplified compounds, the compounds exemplified below have high solvent solubility and thus can be preferably used in a film-forming method by a coating method.

[0064]

[0065]

[0066]

[0067]

[0068] [Organic Compound Layer Included in the Organic Light-Emitting Device According to an Embodiment of the Invention]

[0069] The organic compound layer included in an organic light-emitting device according to one embodiment of the present invention will be described below. The organic light-emitting device according to this embodiment includes at least a first electrode and a second electrode (which are a pair of electrodes), and an organic compound layer provided between these electrodes. In the organic light-emitting device according to this embodiment, the organic compound layer may be formed of a single layer or a stack of multiple layers, as long as it includes a light-emitting layer. The electrode pair may be an anode and a cathode.

[0070] When the organic compound layer is formed by a stack of multiple layers, the organic compound layer may include a light-emitting layer. For example, in addition to the light-emitting layer, the organic compound layer may include a hole injection layer, a hole transport layer, an electron blocking layer, a hole-exciton-blocking layer, an electron transport layer, and an electron injection layer. The light-emitting layer may be formed by a single layer or a stack of multiple layers. The hole transport layer and the electron transport layer are also referred to as charge transport layers.

[0071] In the organic light-emitting device according to this embodiment, at least one layer of the organic compound layer contains the organometallic complex according to this embodiment. Specifically, the organometallic complex according to this embodiment is contained in any layer of the hole injection layer, the hole transport layer, the electron blocking layer, the light-emitting layer, the hole-exciton blocking layer, the electron transport layer, and the electron injection layer, and is preferably contained in the light-emitting layer. The transport layer between the first electrode and the light-emitting layer can be collectively referred to as the first charge transport layer. The transport layer between the second electrode and the light-emitting layer can be collectively referred to as the second charge transport layer. That is, it can be said that the light-emitting layer is in contact with the first charge transport layer and in contact with the second charge transport layer.

[0072] In the organic light-emitting device according to this embodiment, when the organometallic complex according to this embodiment is included in the light-emitting layer, the light-emitting layer may be a layer consisting solely of the organometallic complex according to this embodiment, or may be a layer further comprising a first organic compound and a second organic compound different from the first organic compound in addition to the organometallic complex according to this embodiment. The first organic compound may have a lowest excited triplet energy higher than the lowest excited triplet energy of the iridium complex of the present invention. The lowest excited triplet energy of the second organic compound may be equal to or higher than the lowest excited triplet energy of the organometallic complex of the present invention and equal to or less than the lowest excited triplet energy of the first organic compound. When the light-emitting layer is a layer comprising the first organic compound and the second organic compound, the first organic compound may be the host of the light-emitting layer. The second organic compound may be an auxiliary material. The organometallic complex according to the present invention may be a guest or a dopant.

[0073] As used herein, a host refers to the compound with the highest weight ratio among the compounds contained in the light-emitting layer. A guest or dopant refers to a compound contained in the light-emitting layer that has a lower weight ratio than the host and is primarily responsible for light emission. An auxiliary material refers to a compound contained in the light-emitting layer that has a lower weight ratio than the host and assists in the light emission of the guest. An auxiliary material is also referred to as a secondary host.

[0074] When the organometallic complex according to this embodiment is used as a guest in a light-emitting layer, the concentration of the guest is preferably from 0.01% by weight to 20% by weight, more preferably from 0.1% by weight to 10.0% by weight, based on the entire light-emitting layer. The entire light-emitting layer refers to the total weight of the compounds constituting the light-emitting layer.

[0075] The lowest excited triplet energy of the first charge transport layer is preferably higher than the lowest excited triplet energy of the first organic compound. The lowest excited triplet energy of the second charge transport layer is preferably higher than the lowest excited triplet energy of the first organic compound. The lowest excited triplet energy of the charge transport layer can be estimated based on the lowest excited triplet energy of the constituent materials of the layer. When the charge transport layer contains multiple materials, the lowest excited triplet energy can be the lowest excited triplet energy of the compound having the largest weight ratio.

[0076] The present inventors have conducted various studies and found that when the organometallic complex according to the present embodiment is used as a guest in the light-emitting layer, it exhibits high efficiency and high brightness light output and provides good attenuation characteristics. The light-emitting layer can be formed by a single layer or multiple layers, and can also contain light-emitting materials with other luminescent colors to implement the light-emitting color of the present embodiment and color mixing of other light-emitting colors. The term "multiple layers" refers to a state in which multiple light-emitting layers are stacked. In this case, the light-emitting color of the organic light-emitting device is not limited to the same hue as the light-emitting color of the single layer. More specifically, the light-emitting color can be white or an intermediate color. In the case of white light, red light, blue light, and green light can be emitted from the light-emitting layer to obtain white light, or a combination of complementary light-emitting colors can be used to obtain white light.

[0077] The organometallic complex according to this embodiment can be used as a constituent material of an organic compound layer other than the light-emitting layer included in the organic light-emitting device according to this embodiment. Specifically, the organometallic complex can be used as a constituent material of an electron transport layer, an electron injection layer, a hole transport layer, a hole injection layer, and a hole blocking layer.

[0078] When producing the organic light-emitting device according to this embodiment, for example, a generally known low-molecular-weight or high-molecular-weight hole-injecting compound, a hole-transporting compound, a compound serving as a host, a light-emitting compound, an electron-injecting compound, or an electron-transporting compound can be used together as needed. Examples of these compounds are described below.

[0079] As hole injection / transport material, preferably a material with high hole mobility is used to promote the injection of holes from the anode and to transport the injected holes to the light-emitting layer. In order to reduce the degradation of film quality such as crystallization in organic light-emitting devices, preferably a material with a high glass transition temperature. Examples of low molecular weight or high molecular weight materials with hole injection / transport properties include triarylamine derivatives, arylcarbazole derivatives, phenylenediamine derivatives, triazole derivatives, oxadiazole derivatives, imidazole derivatives, stilbene derivatives, phthalocyanine derivatives, porphyrin derivatives, conductive polymers such as polyarylamine derivatives, poly (vinylcarbazole) derivatives, polythiophene derivatives and PEDOT-PSS, their copolymers and their mixtures. In addition, hole injection / transport material can also be used for electron blocking layer.

[0080] Specific examples of the compound used as the hole injection / transport material are shown below, but the hole injection / transport material is, of course, not limited thereto.

[0081]

[0082]

[0083] As a luminescent material mainly related to the luminescent function, in addition to the organometallic complex according to one embodiment of the present invention, other luminescent materials may be added. Examples of other luminescent materials include fused ring compounds such as fluorene derivatives, naphthalene derivatives, pyrene derivatives, perylene derivatives, tetracene derivatives, anthracene compounds and rubrene, quinacridone derivatives, coumarin derivatives, stilbene derivatives, organic aluminum complexes such as tris(8-hydroxyquinoline)aluminum, iridium complexes such as tris(2-phenylpyridine)iridium, platinum complexes, rhenium complexes, copper complexes, europium complexes, ruthenium complexes, and polymer derivatives such as poly(phenylene vinylene) derivatives, polyfluorene derivatives and polyphenylene derivatives.

[0084] Specific examples of compounds used as the light-emitting material are shown below, but the light-emitting material is, of course, not limited thereto.

[0085]

[0086]

[0087] Examples of the light-emitting layer host or light-emitting auxiliary materials contained in the light-emitting layer include aromatic hydrocarbon compounds and their derivatives, carbazole derivatives, dibenzofuran derivatives, dibenzothiophene derivatives, triazine derivatives, organic aluminum complexes such as tris(8-hydroxyquinoline)aluminum, organic beryllium complexes, polymers such as polyphenylene derivatives, poly(phenylene vinylene) derivatives, polyfluorene derivatives and poly(vinylcarbazole) derivatives, their copolymers and their mixtures.

[0088] Specific examples of compounds used as a light-emitting layer host or a light-emitting auxiliary material contained in the light-emitting layer are shown below, but of course, the light-emitting layer host or the light-emitting auxiliary material is not limited thereto.

[0089]

[0090]

[0091]

[0092] Electron transport material can be freely selected from the material that can transport the electron injected from cathode to the light emitting layer, and is selected in consideration of, for example, the balance with the hole mobility of hole transport material. The example of the material with the ability to transport electrons includes oxadiazole derivatives, oxazole derivatives, pyrazine derivatives, triazole derivatives, triazine derivatives, quinoline derivatives, quinoxaline derivatives, phenanthroline derivatives, organic aluminum complexes and condensed ring compounds (such as fluorene derivatives, naphthalene derivatives, chrysene derivatives and anthracene derivatives). Electron transport material is also preferably used for hole blocking layer.

[0093] Specific examples of the compound used as the electron transport material are shown below, but the electron transport material is, of course, not limited thereto.

[0094]

[0095] The electron injection material can be freely selected from materials that can easily inject electrons from the cathode, and is selected in consideration of, for example, the balance with hole injection properties. Organic compounds also include n-type dopants and reductive dopants. Examples include alkali metal compounds such as lithium fluoride, lithium complexes such as lithium hydroxyquinoline, benzimidazolidine derivatives, imidazoline derivatives, fulvalene derivatives, and acridine derivatives.

[0096] [Structure of organic light-emitting device]

[0097] An organic light-emitting device is provided by forming a first electrode, an organic compound layer, and a second electrode on an insulating layer provided on a substrate. A protective layer, a color filter, and the like may be provided on the second electrode. When a color filter is provided, a planarization layer may be provided between the color filter and the protective layer. The planarization layer may be made of, for example, an acrylic resin. One of the first and second electrodes may be an anode, and the other may be a cathode.

[0098] [Substrate]

[0099] Examples of substrates include quartz, glass, silicon wafers, resins, and metals. The substrate may include switching elements such as transistors, wires, and an insulating layer thereon. As the insulating layer, any material can be used as long as a contact hole can be formed to establish an electrical connection between the anode and the wire, and as long as insulation from unconnected wires can be ensured. For example, a resin such as polyimide, silicon oxide, or silicon nitride can be used.

[0100] [electrode]

[0101] A pair of electrodes can be used. This pair can be an anode and a cathode. When an electric field is applied in the direction of light emission from the organic light-emitting device, the electrode with the higher potential becomes the anode, and the other electrode becomes the cathode. Alternatively, the electrode that supplies holes to the light-emitting layer is the anode, and the electrode that supplies electrons is the cathode.

[0102] As the constituent material of the anode, a material having a work function as high as possible is preferred. Examples of operable materials include elemental metals such as gold, platinum, silver, copper, nickel, palladium, cobalt, selenium, vanadium and tungsten, mixtures thereof, alloys of their combinations, and metal oxides such as tin oxide, zinc oxide, indium oxide, indium tin oxide (ITO) and indium zinc oxide. Alternatively, conductive polymers such as polyaniline, polypyrrole and polythiophene can be used.

[0103] These electrode materials may be used alone or in combination of two or more. The anode may be formed of a single layer or a plurality of layers.

[0104] When the anode is used as a reflective electrode, for example, chromium, aluminum, silver, titanium, tungsten, molybdenum, alloys thereof, or laminates thereof can be used. When the anode is used as a transparent electrode, a transparent conductive oxide layer composed of, for example, indium tin oxide (ITO) or indium zinc oxide can be used; however, the anode is not limited thereto. The electrode can be formed by photolithography.

[0105] As the constituent material of the cathode, a material with a lower work function is preferably used. Examples thereof include elemental metals, such as alkali metals such as lithium, alkaline earth metals such as calcium, aluminum, titanium, manganese, silver, lead and chromium, and mixtures thereof. Alloys of combinations of these elemental metals may also be used. For example, magnesium-silver, aluminum-lithium, aluminum-magnesium, silver-copper and zinc-silver may be used. Metal oxides such as indium tin oxide (ITO) may also be used. These electrode materials may be used alone or in combination of two or more. The cathode may have a single-layer structure or a multilayer structure. Among these, silver is preferably used, and in order to suppress the aggregation of silver, a silver alloy is more preferably used. There is no restriction on the alloy ratio as long as the aggregation of silver can be suppressed. For example, it may be 1:1.

[0106] A top-emitting device can be provided using a cathode formed from a conductive oxide layer, such as indium tin oxide (ITO). A bottom-emitting device can be provided using a cathode formed from a reflective electrode, such as aluminum (Al). Any type of cathode can be used. There are no particular limitations on the method used to form the cathode, but DC sputtering or AC sputtering is more preferred because good film coverage is achieved, thereby easily reducing resistance.

[0107] [Protective layer]

[0108] A protective layer can be configured on the cathode. For example, a glass member provided with a moisture absorbent can be bonded to the cathode to reduce, for example, water from entering the organic compound layer, thereby reducing the occurrence of display defects. In another embodiment, a passivation film composed of, for example, silicon nitride can be configured on the cathode to reduce, for example, water from entering the organic compound layer. For example, after forming the cathode, the substrate can be transported to another chamber without breaking the vacuum, and a silicon nitride film with a thickness of 2 μm can be formed by a CVD method to provide a protective layer. After film deposition by the CVD method, a protective layer can be formed by an atomic layer deposition (ALD) method.

[0109] [Color Filter]

[0110] A color filter can be placed on the protective layer. For example, depending on the size of the organic light-emitting device, the color filter can be placed on another substrate and bonded to the substrate on which the organic light-emitting device is mounted. The color filter can be formed by patterning the protective layer using photolithography. The color filter can be made of a polymer.

[0111] [Planarization layer]

[0112] A planarization layer may be disposed between the color filter and the protective layer. The planarization layer may be composed of an organic compound. Low molecular weight or high molecular weight organic compounds may be used. High molecular weight organic compounds are preferred.

[0113] The planarization layer may be disposed above and below (or on) the color filter and may be composed of the same or different constituent materials. Specific examples thereof include poly(vinyl carbazole) resins, polycarbonate resins, polyester resins, ABS resins, acrylic resins, polyimide resins, phenolic resins, epoxy resins, silicone resins, and urea-formaldehyde resins.

[0114] [Countering substrate]

[0115] A counter substrate may be disposed on the planarization layer. This counter substrate is disposed in a position corresponding to the aforementioned substrate and is therefore referred to as a counter substrate. This counter substrate may be made of the same material as the aforementioned substrate. When the aforementioned substrate is referred to as the first substrate, the counter substrate may be referred to as the second substrate.

[0116] [Formation of Organic Compound Layer]

[0117] The organic compound layer (such as a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, a hole blocking layer, an electron transport layer, or an electron injection layer) included in the organic light emitting device according to an embodiment of the present invention is formed by the method described below.

[0118] The organic compound layer constituting the organic light emitting device according to the embodiment of the present invention can be formed by a dry process or a wet process without any particular limitation. The example of the dry process that can be used includes vacuum evaporation, ionization evaporation, sputtering and plasma method. The example of wet process includes using a known coating method (for example, spin coating, casting, micro gravure coating, gravure coating, rod coating, roller coating, wire rod coating, dip coating, spray coating, screen printing, flexographic printing, offset printing, inkjet printing, capillary coating and nozzle coating) of a solution prepared by dissolving the compound in a suitable solvent. Among these, vacuum evaporation, ionization evaporation, inkjet printing and nozzle coating are suitable for manufacturing an organic light emitting device with a large area.

[0119] The thickness of each layer in the organic light-emitting device is preferably generally 1 nm to 10 μm. In particular, the thickness of the light-emitting layer of the organic compound layer is preferably 10 nm to 100 nm in order to obtain efficient light-emitting characteristics.

[0120] When the organic compound layer is formed by a wet process, the composition of these layers is dissolved in a solvent to form an ink. The viscosity of each ink can be adjusted according to the type of printing method. When such an ink is used in a printing method such as inkjet printing, in which the solution passes through a discharge device, the viscosity at 25°C is preferably 1 to 20 mPa·s to reduce clogging and flight deflection during the discharge process.

[0121] Typically, a solvent having a boiling point of 70° C. to 300° C. at 1 atmosphere can be used for the ink. The amount of the organic solvent is typically 10 to 100 parts by mass based on 1 part by mass of the material constituting each organic compound layer.

[0122] The drying of the coating obtained by the wet process can be appropriately selected according to the type of each layer. Generally, heating can be carried out at 100°C to 250°C, preferably 110°C to 200°C, for 5 to 60 minutes under an air atmosphere or an inert gas (nitrogen, argon, etc.) atmosphere. Alternatively, heating can be carried out under normal pressure (1 atmosphere) or under reduced pressure (100Pa to 0.1MPa). The temperature, pressure and time in the drying step can be adjusted to remove the solvent in each layer.

[0123] When forming a film by a coating method, the film may be formed in combination with an appropriate binder resin.

[0124] Examples of the binder resin include, but are not limited to, poly(vinylcarbazole) resins, polycarbonate resins, polyester resins, ABS resins, acrylic resins, polyimide resins, phenolic resins, epoxy resins, silicone resins, and urea resins.

[0125] These binder resins may be used alone as a homopolymer or a copolymer, or in combination as a mixture of two or more thereof. In addition, additives such as known plasticizers, antioxidants, and ultraviolet absorbers may be used as needed.

[0126] [Pixel circuit]

[0127] The light-emitting device may include a pixel circuit connected to the light-emitting device. Each pixel circuit may be an active matrix type that independently controls the light emission of the first light-emitting device and the second light-emitting device. The active matrix type circuit may be voltage-programmed or current-programmed. The driving circuit includes a pixel circuit for each pixel. The pixel circuit may include a light-emitting device, a transistor for controlling the brightness of the light-emitting device, a transistor for controlling the timing of light emission, a capacitor for maintaining the gate voltage of the transistor for controlling the brightness, and a transistor for connecting to GND when the light-emitting device is not in use.

[0128] The light-emitting device includes a display area and a peripheral area arranged around the display area. The display area includes a pixel circuit, and the peripheral area includes a display control circuit. The mobility of the transistor included in the pixel circuit may be lower than the mobility of the transistor included in the display control circuit.

[0129] The slope of the current-voltage characteristic of the transistor included in the pixel circuit may be smaller than the slope of the current-voltage characteristic of the transistor included in the display control circuit. The slope of the current-voltage characteristic can be measured by the so-called Vg-Ig characteristic.

[0130] The transistor included in the pixel circuit is a transistor connected to a light emitting device such as the first light emitting device.

[0131] [Pixels]

[0132] An organic light-emitting device includes a plurality of pixels. Each pixel includes sub-pixels configured to emit different colors. The sub-pixels can have respective RGB emission colors.

[0133] Light is emitted from the area of the pixel (also called the pixel aperture). The pixel aperture can be 15 μm or less, and can be 5 μm or more. More specifically, the pixel aperture can be, for example, 11 μm, 9.5 μm, 7.4 μm, or 6.4 μm.

[0134] The distance between sub-pixels may be 10 μm, specifically, 8 μm, 7.4 μm, or 6.4 μm.

[0135] In a planar view, the pixels can be arranged in a known pattern. For example, a stripe pattern, a triangle pattern, a Pen Tile matrix pattern, or a Bayer pattern can be used. In a planar view, the shape of each sub-pixel can be any known shape. Examples of sub-pixel shapes include quadrilaterals, such as rectangles and diamonds, and hexagons. Of course, if the shape is close to a rectangle, rather than an exact shape, it is included in the rectangle. The shape of the sub-pixel and the pixel arrangement can be used in combination.

[0136] [Use of the organic light-emitting device according to the embodiment of the present invention]

[0137] The organic light-emitting device according to the embodiment of the present invention can be used as a component of a display device or a lighting device. Other uses include exposure light sources for electrophotographic imaging devices, backlights for liquid crystal displays, and light-emitting devices including white light sources and color filters.

[0138] The display device may be an image information processing unit having an image input unit that receives image information from an area or linear CCD sensor, a memory card, or any other source, an information processing unit that processes the input information, and a display unit that displays the input image.

[0139] The display unit of an imaging device or inkjet printer may have a touch panel function. The driving mode of the touch panel function may be, but is not particularly limited to, an infrared mode, an electrostatic capacitance mode, a resistive film mode, or an electromagnetic induction mode. The display device may also be used in the display unit of a multifunction printer.

[0140] The display device according to the present embodiment will be described below with reference to the drawings.

[0141] Figure 1A 1 is a schematic cross-sectional view of an example of a pixel of a display device according to this embodiment. Each pixel includes a sub-pixel 10. The sub-pixels are divided into 10R, 10G, and 10B according to their light emission. The emission color can be distinguished by the wavelength of the light emitted from the light-emitting layer. The light emitted from the sub-pixels can be selectively transmitted or color-converted using, for example, a color filter. Each sub-pixel includes a reflective electrode 2 serving as a first electrode on an interlayer insulating layer 1, an insulating layer 3 covering the edge of the reflective electrode 2, an organic compound layer 4 covering the first electrode and the insulating layer, a transparent electrode 5, a protective layer 6, and a color filter 7.

[0142] Transistors and capacitors may be provided below or within the interlayer insulating layer 1. Each transistor may be electrically connected to a corresponding one of the first electrodes through a contact hole (not shown).

[0143] The insulating layer 3 is also called a bank or a pixel separation film. The insulating layer covers the edge of each first electrode and surrounds the first electrode. The portion not covered by the insulating layer is in contact with the organic compound layer 4 and serves as a light-emitting region.

[0144] The organic compound layer 4 includes a hole injection layer 41, a hole transport layer 42, a first light emitting layer 43, a second light emitting layer 44, and an electron transport layer 45. The second electrode 5 may be a transparent electrode, a reflective electrode, or a semi-transparent electrode.

[0145] The protective layer 6 reduces the penetration of moisture into the organic compound layer. Although the protective layer is shown as a single layer, the protective layer may include a plurality of layers, and each layer may be an inorganic compound layer or an organic compound layer.

[0146] Color filters 7 are divided into 7R, 7G, and 7B according to their colors. The color filters can be arranged on a planarization film (not shown). A resin protective layer (not shown) can be arranged on the color filters. The color filters can be arranged on the protective layer 6. Alternatively, the color filters can be arranged on a counter substrate such as a glass substrate and then bonded.

[0147] Figure 1B 1 is a schematic cross-sectional view of an example of a display device including an organic light-emitting device and a transistor connected to the corresponding organic light-emitting device. Each transistor is an example of an active element. The transistor can be a thin film transistor (TFT).

[0148] Figure 1B The display device 100 shown includes a substrate 11 made of, for example, glass or silicon, and an insulating layer 12 provided thereon. Active elements such as TFTs 18 are provided on the insulating layer. A gate electrode 13, a gate insulating film 14, and a semiconductor layer 15 are provided for each active element. Each TFT 18 includes a semiconductor layer 15, a drain electrode 16, and a source electrode 17. An insulating film 19 is provided over the TFTs 18. An anode 21 included in the organic light-emitting device is connected to the source electrode 17 via a contact hole 20 provided in the insulating film.

[0149] The electrical connection between the electrodes (anode and cathode) included in each organic light emitting device and the electrodes (source electrode and drain electrode) included in a corresponding one of the TFTs is not limited to Figure 1B That is, it is sufficient that any one of the anode and cathode is electrically connected to any one of the source electrode and drain electrode of the TFT. The term "TFT" refers to a thin film transistor.

[0150] exist Figure 1B In the display device 100 shown, each organic compound layer is shown as a single layer; however, the organic compound layer 22 may be formed of multiple layers. In order to reduce degradation of the organic light-emitting device, a first protective layer 24 and a second protective layer 25 are provided on the cathode 23.

[0151] exist Figure 1B In the illustrated display device 100 , although transistors are used as switching elements, other switching elements may be used instead.

[0152] exist Figure 1B The transistors used in the display device 100 shown are not limited to those using a single-crystal silicon wafer. Instead, they may be thin-film transistors including an active layer on an insulating surface of a substrate. Examples of materials for the active layer include single-crystal silicon, non-single-crystal silicon materials such as amorphous silicon and microcrystalline silicon, and non-single-crystal oxide semiconductors such as indium zinc oxide and indium gallium zinc oxide. Thin-film transistors are also referred to as TFT elements.

[0153] Figure 1B The transistors in the display device 100 shown may be formed in a substrate such as a Si substrate. The expression "formed in a substrate" indicates that the transistors are produced by processing a substrate such as a Si substrate. When the transistors are formed in the substrate, it can be considered that the substrate and the transistors are formed integrally.

[0154] In the organic light-emitting device according to this embodiment, the brightness is controlled by a TFT, which is an example of a switching element; therefore, by arranging multiple organic light-emitting devices in a plane, an image can be displayed at a corresponding brightness level. The switching element according to this embodiment is not limited to a TFT element and can be a low-temperature polysilicon transistor or an active matrix driver formed on a substrate such as a Si substrate. The expression "on the substrate" can also be referred to as "in the substrate." Whether to form transistors in the substrate or use TFTs is selected according to the size of the display unit. For example, when the display unit has a size of approximately 0.5 inches, the organic light-emitting device is preferably configured on the Si substrate.

[0155] Figure 2 1 is a schematic diagram illustrating an example of a display device according to this embodiment. Display device 1000 may include a touch panel 1003, a display panel 1005, a frame 1006, a circuit board 1007, and a battery 1008, which are arranged between an upper cover 1001 and a lower cover 1009. Touch panel 1003 and display panel 1005 are connected to flexible printed circuits (FPCs) 1002 and 1004, respectively. Circuit board 1007 includes printed transistors. Unless the display device is a portable device, battery 1008 does not need to be provided. Even if the display device is a portable device, battery 1008 may be arranged in a different position.

[0156] The display device according to the present embodiment may include a color filter having red, green, and blue portions. In the color filter, red, green, and blue may be arranged in a delta arrangement, a stripe arrangement, or a mosaic arrangement.

[0157] The display device according to this embodiment can be used as a display unit of a portable terminal. In this case, the display device can have both a display function and an operation function. Examples of portable terminals include portable phones such as smartphones, tablet computers, and head-mounted displays.

[0158] The display device according to this embodiment can be used as a display unit of an imaging device, which includes an optical unit having multiple lenses and an imaging device that receives light passing through the optical unit. The imaging device may include a display unit that displays information acquired by the imaging device. The display unit may be a display unit exposed to the outside of the imaging device or a display unit configured in a viewfinder. The imaging device may be a digital camera or a digital video camera. The imaging device may also be referred to as a photoelectric conversion device.

[0159] Figure 3A 1 is a schematic diagram illustrating an example of an imaging device according to this embodiment. Imaging device 1100 may include a viewfinder 1101, a rear display 1102, an operating unit 1103, and a housing 1104. Viewfinder 1101 may include a display device according to this embodiment. In this case, in addition to the captured image, the display device may also display environmental information, imaging instructions, and the like. Environmental information may include, for example, the intensity of external light, the direction of external light, the speed of movement of a target, and the possibility that the target is obscured by a shielding material.

[0160] The window of opportunity for imaging is only short; therefore, information can be displayed as quickly as possible. Therefore, display devices including organic light-emitting devices according to the present invention are preferred. This is because organic light-emitting devices have a high response speed. Compared to liquid crystal displays, display devices including organic light-emitting devices are more suitable for devices requiring high display speeds.

[0161] The imaging device 1100 includes an optical unit (not shown). The optical unit includes a plurality of lenses and is configured to form an image on an imaging device within a housing 1104. The relative positions of the plurality of lenses can be adjusted to adjust the focus. This operation can also be performed automatically.

[0162] Figure 3B1 is a schematic diagram showing an example of an electronic device according to the present embodiment. The electronic device 1200 includes a display unit 1201, an operating unit 1202 and a housing 1203. The housing 1203 can accommodate a circuit, a printed circuit board including the circuit, a battery and a communication unit. The operating unit 1202 can be a button or a touch panel type reaction unit. The operating unit can be a biometric unit that recognizes a fingerprint to release a lock, etc. An electronic device including a communication unit can also be referred to as a communication device. The electronic device can further have a camera function by being equipped with a lens and a camera device. The image captured by the camera function is displayed on the display unit. Examples of electronic devices include smart phones and notebook computers.

[0163] Figure 4A and Figure 4B Each is a schematic diagram showing an example of a display device according to the present embodiment. Figure 4A 13 shows a display device such as a TV monitor or a PC monitor. Display device 1300 includes a frame 1301 and a display unit 1302. Display unit 1302 may include a light emitting device according to this embodiment.

[0164] A base 1303 is provided to support the frame 1301 and the display unit 1302. The base 1303 is not limited to Figure 4A The structure shown in FIG. The underside of the frame 1301 can also be used as a base.

[0165] The frame 1301 and the display unit 1302 may be curved and may have a curvature radius of 5,000 mm or more and 6,000 mm or less.

[0166] Figure 4B is a schematic diagram showing another example of the display device according to the present embodiment. Figure 4B The display device 1310 shown in FIG can be folded and is a so-called foldable display device. The display device 1310 includes a first display portion 1311, a second display portion 1312, a housing 1313, and a bending point 1314. The first display portion 1311 and the second display portion 1312 may include a light-emitting device according to this embodiment. The first display portion 1311 and the second display portion 1312 may be a single seamless display device. The first display portion 1311 and the second display portion 1312 may be separated from each other at the bending point. The first display portion 1311 and the second display portion 1312 may display different images from each other. Alternatively, a single image may be displayed in the first display portion and the second display portion.

[0167] Figure 5A14 is a schematic diagram illustrating an example of a lighting device according to this embodiment. Lighting device 1400 may include a housing 1401, a light source 1402, a circuit board 1403, an optical film 1404, and a light diffusion unit 1405. The light source may include an organic light-emitting device according to this embodiment. The optical film may be a filter that improves the color rendering properties of the light source. When used for lighting, etc., the light diffusion unit can effectively diffuse light from the light source to transmit the light to a wide range. The optical film and the light diffusion unit may be arranged on the light emitting side of the lighting device. A cover may be arranged on the outermost side as needed.

[0168] A lighting device is, for example, a device that illuminates a room. The lighting device can emit white, neutral white, or any color of light from blue to red. A light control circuit may be provided to control the light. The lighting device may include an organic light-emitting device according to the present invention and a power supply circuit connected thereto. The power supply circuit is a circuit that converts AC voltage into DC voltage. The color temperature of white is 4,200K, and the color temperature of neutral white is 5,000K. The lighting device may include a color filter.

[0169] The lighting device according to this embodiment may include a heat dissipation unit configured to release heat in the device to the outside of the device, and may be made of, for example, metal or liquid silicone having high specific heat.

[0170] Figure 5B 1 is a schematic diagram showing a car as an example of a mobile body according to the present embodiment. The car includes taillights as an example of a lighting unit. The car 1500 includes taillights 1501 and can be configured to light up when a braking operation is performed, etc.

[0171] Taillight 1501 may include an organic light-emitting device according to this embodiment. The taillight may include a protective member to protect the organic light-emitting device. The protective member may be made of any transparent material having a certain degree of strength, and is preferably made of, for example, polycarbonate. The polycarbonate may be mixed with, for example, a furandicarboxylic acid derivative or an acrylonitrile derivative.

[0172] Automobile 1500 may include an automobile body 1503 and windows 1502 mounted thereto. If the windows are not used to inspect areas in front of or behind the automobile, they may be transparent displays. The transparent display may include an organic light-emitting device according to this embodiment. In this case, the constituent materials of the organic light-emitting device, such as electrodes, are formed from transparent members.

[0173] The mobile object according to this embodiment may be, for example, a ship, an airplane, or a drone. The mobile object may include a body and a lighting unit attached to the body. The lighting unit may emit light to indicate the position of the body. The lighting unit may include the organic light-emitting device according to this embodiment.

[0174] Will refer to Figure 6A and Figure 6B An example of an application of the display device of the above embodiment will be described. The display device can be used in a wearable system such as smart glasses, head-mounted displays (HMDs), and smart contact lenses. The imaging device and display device used in this example of an application include an imaging device that can photoelectrically convert visible light and a display device that can emit visible light.

[0175] Figure 6A Glasses 1600 (smart glasses) according to an application example are shown. An imaging device 1602, such as a CMOS sensor or SPAD, is provided on the front side of a lens 1601 of the glasses 1600. A display device according to any of the above embodiments is provided on the rear side of the lens 1601.

[0176] The glasses 1600 further include a control unit 1603. The control unit 1603 serves as a power source for supplying power to the imaging device 1602 and the display device according to any embodiment. The control unit 1603 controls the operation of the imaging device 1602 and the display device. The lens 1601 has an optical system for focusing light on the imaging device 1602.

[0177] Figure 6B Glasses 1610 (smart glasses) according to an application example are shown. Glasses 1610 include a control unit 1612. Control unit 1612 includes a camera and a display device corresponding to camera 1602. Lens 1611 is equipped with a camera within control unit 1612 and an optical system for projecting light emitted from the display device. An image is projected onto lens 1611. Control unit 1612 serves as a power supply for supplying power to the camera and display devices and controls the operation of the camera and display devices. The control unit may include a line of sight detection unit for detecting the wearer's line of sight. Infrared light can be used for line of sight detection. The infrared light emitting unit emits infrared light toward the eyeball of the user who is looking at the displayed image. An image of the eyeball is captured by detecting the infrared light reflected from the eyeball using a camera unit having a light receiving element. Deterioration in image quality is reduced by providing a reduction unit configured to reduce the amount of light from the infrared light emitting unit to the display unit when viewed in a plan view.

[0178] The user's gaze toward the displayed image is detected from an image of the eyeball captured using infrared light. Any known method can be used for gaze detection using a captured image of the eyeball. For example, a gaze detection method based on a Purkinje image of reflection of irradiated light on the cornea can be used.

[0179] More specifically, gaze detection processing is performed based on the pupil-corneal reflection method. Using the pupil-corneal reflection method, the user's gaze is detected by calculating a gaze vector representing the direction (rotation angle) of the eyeball based on an image of the pupil and a Purkinje image included in a captured image of the eyeball.

[0180] A display device according to an embodiment of the present invention may include an imaging device including a light receiving element, and may control an image displayed on the display device based on visual line information of a user from the imaging device.

[0181] Specifically, in the display device, a first field of view area at which the user is looking and a second field of view area other than the first field of view area are determined based on the line of sight information. The first field of view area and the second field of view area can be determined by a control unit of the display device, or can be determined by receiving those determined by an external control unit. Within the display area of the display device, the display resolution of the first field of view area can be controlled to be higher than the display resolution of the second field of view area. In other words, the resolution of the second field of view area can be lower than the resolution of the first field of view area.

[0182] The display area includes a first display area and a second display area different from the first display area. Based on the line of sight information, a higher priority area is determined from the first display area and the second display area. The first display area and the second display area can be determined by the control unit of the display device, or can be determined by receiving those determined by an external control unit. The resolution of the higher priority area can be controlled to be higher than the resolution of areas other than the higher priority area. In other words, the resolution of the relatively low priority area can be low.

[0183] Artificial intelligence (AI) can be used to determine the first field of view area and the high-priority area. The AI can be a model configured to use an image of the eyeball and the actual gaze direction of the eyeball in the image as teaching data to estimate the sight angle from the image of the eyeball and the distance to the target object located in the gaze direction. The AI program can be stored in a display device, a camera device, or an external device. When the AI program is stored in an external device, the AI program is transmitted to the display device via communication.

[0184] In the case of controlling the display based on visual detection, smart glasses that also include a camera device for capturing external images can be used. The smart glasses can display the captured external information in real time.

[0185] As described above, use of an apparatus including the organic light-emitting device according to the present embodiment enables stable display with good image quality even for a long time.

[0186] As described above, a device including the organic light emitting device according to the present embodiment can achieve good outdoor visibility and energy-saving display due to high efficiency and high brightness light output.

[0187] Example

[0188] Examples will be described below. However, the present invention is not limited to these examples.

[0189] [Synthesis example 1]

[0190] Synthesis of compound (4)

[0191]

[0192] Compound (4) was synthesized by the following steps. First, the synthesis of the ligand will be described. In a nitrogen atmosphere, 2.12 g (10.5 mmol) of dibenzofuran-4-boric acid, 1.70 g (10.0 mmol) of 4-(tert-butyl)-2-chloropyridine, 0.12 g (0.1 mmol) of tetrakis(triphenylphosphine)palladium, 30 mL of toluene, 15 ml of ethanol and 15 ml of 2M aqueous sodium carbonate solution were placed in a 100 ml recovery flask. The mixture was heated from room temperature to 90°C and stirred for 4 hours. Toluene and water were added thereto. The organic layer was extracted. Magnesium sulfate was added to the obtained organic layer and then filtered. The filtrate was concentrated and purified by silica gel column chromatography (mobile phase: chloroform). The solvent was removed by evaporation and crystallized using an aqueous solution of isopropyl alcohol (IPA) to obtain 3.00 g of the ligand. By 1 The structure was confirmed by H NMR and MS.

[0193] The synthesis of compound (4) will be described below.

[0194]

[0195] In a nitrogen atmosphere, 70.5 mg (0.2 mmol) of iridium chloride trihydrate, 3.00 g (9.95 mmol) of ligand and 20 ml of ethylene glycol were placed in a 100 ml recovery flask. The mixture was irradiated with microwaves (150 W) for 1 hour. Water was added to the reaction mixture. The mixture was filtered by suction. Repeated dispersion washing with methanol gave 220 mg of compound (4) as a yellow solid. HPLC analysis showed a purity of 99.5%. The product was purified by MS and 1 The structure was confirmed by H NMR.

[0196] MS analysis: 1093.377

[0197] 1H NMR analysis (500MHz, CDCl3): 9.03(1H,d,J / Hz=1.5), 7.80(1H,d,J / Hz=8.0), 7.57(1H,d,J / Hz=8.0), 7.52(1H,d,J / Hz=6.0), 7.39(1H,d,J / Hz=8.0),7.35(1H,dt,J / Hz=8.0,1.0),7.26(1H,dt,J / Hz=8.0,1.0),6.96(1H,dd,J / Hz=6.0,2.0),6.90(1H,d,J / Hz=8.0),1.41(9H,s)

[0198] [Synthesis example 2]

[0199] Synthesis of compound (13)

[0200]

[0201] Compound (13) was synthesized in the same manner as in Synthesis Example 1, except that 4-phenyl-2-chloropyridine was used instead of 4-(tert-butyl)-2-chloropyridine. HPLC analysis showed a purity of 99.4%. The structure was identified by MS.

[0202] MS analysis: 1153.280

[0203] [Synthesis example 3]

[0204] Synthesis of compound (56)

[0205]

[0206] Compound (56) was synthesized in the same manner as in Synthesis Example 1, except that 1-methyldibenzofuran-4-boronic acid was used instead of dibenzofuran-4-boronic acid. HPLC analysis showed a purity of 99.2%. The structure was identified by MS.

[0207] MS analysis: 1135.424

[0208] [Synthesis Example 4]

[0209] Synthesis of compound (58)

[0210]

[0211] Compound (58) was synthesized in the same manner as in Synthesis Example 1 except that 4-cyclohexyl-2-chloropyridine was used instead of 4-(tert-butyl)-2-chloropyridine. HPLC analysis showed a purity of 99.5%. The structure was identified by MS.

[0212] MS analysis: 1213.475

[0213] [Synthesis Example 5]

[0214] Synthesis of compound (70)

[0215]

[0216] Compound (70) was synthesized in the same manner as in Synthesis Example 1, except that 1-ethyldibenzofuran-4-boronic acid was used instead of dibenzofuran-4-boronic acid. HPLC analysis showed a purity of 99.2%. The structure was identified by MS.

[0217] MS analysis: 1177.474

[0218] [Example 1]

[0219] By 3×10 -3 Compound (4) prepared in Synthesis Example 1 was purified by sublimation at 360° C. under Pa. The HPLC purity of the sublime was 99.9%. Using the sublime, an organic light-emitting device having a structure of anode / hole injection layer / hole transport layer / electron blocking layer / luminescent layer / hole blocking layer / electron transport layer / cathode provided in this order on a substrate was produced as follows.

[0220] An ITO film serving as an anode was formed on a glass substrate with a thickness of 100 nm by sputtering, and the resulting substrate was used as a transparent conductive supporting substrate (ITO substrate). -5 The organic compound layer and the electrode layer described below were continuously formed on the ITO substrate using vacuum deposition with resistance heating in a vacuum chamber with a pressure of 1.5 Pa. At this time, the electrode was formed to have a thickness of 3 mm. 2 The opposing electrode area.

[0221] Hole injection layer (10nm) HT16

[0222] Hole transport layer (40nm) HT1

[0223] Light-emitting layer (30 nm): Host material: EM32, Guest material: Compound (4) (4 wt%)

[0224] Electron transport layer (30nm) ET20

[0225] Metal electrode layer 1 (15nm) LiF

[0226] Metal electrode layer 2 (100nm) Al

[0227] In order not to cause degradation of the organic light-emitting device due to moisture adsorption, the resulting structure was covered with a protective glass plate in a dry air atmosphere and sealed with an acrylic resin adhesive.

[0228] The current efficiency of the obtained organic light-emitting device was measured using an ITO electrode as an anode and an Al electrode as a cathode. 2 The current efficiency is 94.8cd / A at a current density of 50mA / cm 2 The current efficiency at a current density of 1.5 GHz is 79.2 cd / A.

[0229] [Example 2]

[0230] Compound (13) prepared in Synthesis Example 2 was purified by sublimation in the same manner as in the case of Compound (4) in Example 1 to obtain a sublimate having an HPLC purity of 99.8%. An organic light-emitting device was produced in the same manner as in Example 1, except that the sublimate of Example 2 was used instead of the sublimate of Example 1.

[0231] The current efficiency of the obtained organic light-emitting device was measured using an ITO electrode as an anode and an Al electrode as a cathode. 2 The current efficiency is 95.0cd / A at a current density of 50mA / cm 2 The current efficiency at a current density of 80.5 cd / A.

[0232] [Example 3]

[0233] Compound (56) prepared in Synthesis Example 3 was purified by sublimation in the same manner as in the case of Compound (4) in Example 1 to obtain a sublimate having an HPLC purity of 99.9%. An organic light-emitting device was produced in the same manner as in Example 1, except that the sublimate of Example 3 was used instead of the sublimate of Example 1.

[0234] The current efficiency of the obtained organic light-emitting device was measured using an ITO electrode as an anode and an Al electrode as a cathode. 2 The current efficiency is 91.1cd / A at a current density of 50mA / cm 2 The current efficiency at a current density of 1.5 wt% is 77.9 cd / A.

[0235] [Example 4]

[0236] Compound (58) prepared in Synthesis Example 4 was purified by sublimation in the same manner as in the case of Compound (4) in Example 1 to obtain a sublimate having an HPLC purity of 99.9%. An organic light-emitting device was produced in the same manner as in Example 1, except that the sublimate of Example 4 was used instead of the sublimate of Example 1.

[0237] The current efficiency of the obtained organic light-emitting device was measured using an ITO electrode as an anode and an Al electrode as a cathode. 2The current efficiency is 92.5cd / A at a current density of 50mA / cm 2 The current efficiency at a current density of 100 nm is 75.5 cd / A.

[0238] [Example 5]

[0239] Compound (70) prepared in Synthesis Example 5 was purified by sublimation in the same manner as in the case of Compound (4) in Example 1 to obtain a sublimate having an HPLC purity of 99.9%. An organic light-emitting device was produced in the same manner as in Example 1, except that the sublimate of Example 5 was used instead of the sublimate of Example 1.

[0240] The current efficiency of the obtained organic light-emitting device was measured using an ITO electrode as an anode and an Al electrode as a cathode. 2 The current efficiency is 93.0cd / A at a current density of 50mA / cm 2 The current efficiency at a current density of 100 nm is 78.1 cd / A.

[0241] [Reference Example 1]

[0242] Ir(ppy)3 was purified by sublimation in the same manner as in the case of compound (4) of Example 1 to obtain a sublimate having an HPLC purity of 99.9%. An organic light-emitting device was produced in the same manner as in Example 1, except that the sublimate of Reference Example 1 was used instead of the sublime of Example 1.

[0243] The current efficiency of the obtained organic light-emitting device was measured using an ITO electrode as an anode and an Al electrode as a cathode. 2 The current efficiency is 75.0cd / A at a current density of 50mA / cm 2 The current efficiency at a current density of 1.5 wt % is 62.3 cd / A.

[0244] [Comparative Example 1]

[0245] Comparative compound (1) was purified by sublimation in the same manner as in the case of compound (4) of Example 1 to obtain a sublimate having an HPLC purity of 99.9%. An organic light-emitting device was produced in the same manner as in Example 1, except that the sublimate of Comparative Example 1 was used instead of the sublimate of Example 1.

[0246] The current efficiency of the obtained organic light-emitting device was measured using an ITO electrode as an anode and an Al electrode as a cathode. 2 The current efficiency is 85.1cd / A at a current density of 50mA / cm 2 The current efficiency at a current density of 1.5 GHz is 65.8 cd / A.

[0247] [Comparative Example 2]

[0248] Comparative compound (2) was purified by sublimation in the same manner as in the case of compound (4) of Example 1 to obtain a sublimate having an HPLC purity of 99.9%. An organic light-emitting device was produced in the same manner as in Example 1, except that the sublimate of Comparative Example 2 was used instead of the sublimate of Example 1.

[0249] The current efficiency of the obtained organic light-emitting device was measured using an ITO electrode as an anode and an Al electrode as a cathode. 2 The current efficiency is 86.9cd / A at a current density of 50mA / cm 2 The current efficiency at a current density of 1.5 wt % is 65.0 cd / A.

[0250] [Comparative Example 3]

[0251] Comparative compound (3) was purified by sublimation in the same manner as in the case of compound (4) of Example 1 to obtain a sublimate having an HPLC purity of 99.9%. An organic light-emitting device was produced in the same manner as in Example 1, except that the sublimate of Comparative Example 3 was used instead of the sublimate of Example 1.

[0252] The current efficiency of the obtained organic light-emitting device was measured using an ITO electrode as an anode and an Al electrode as a cathode. 2 The current efficiency is 79.3cd / A at a current density of 50mA / cm 2 The current efficiency at a current density of 1.5 wt % is 62.0 cd / A.

[0253] [Comparative Example 4]

[0254] Comparative compound (4) was purified by sublimation in the same manner as in the case of compound (4) of Example 1 to obtain a sublimate having an HPLC purity of 99.8%. An organic light-emitting device was produced in the same manner as in Example 1, except that the sublimate of Comparative Example 4 was used instead of the sublimate of Example 1.

[0255] The current efficiency of the obtained organic light-emitting device was measured using an ITO electrode as an anode and an Al electrode as a cathode. 2 The current efficiency is 84.8cd / A at a current density of 50mA / cm 2 The current efficiency at a current density of 100 nm is 66.5 cd / A.

[0256] [Comparative Example 5]

[0257] Comparative compound (5) was purified by sublimation in the same manner as in the case of compound (4) of Example 1 to obtain a sublimate having an HPLC purity of 99.6%. An organic light-emitting device was produced in the same manner as in Example 1, except that the sublimate of Comparative Example 5 was used instead of the sublimate of Example 1.

[0258] The current efficiency of the obtained organic light-emitting device was measured using an ITO electrode as an anode and an Al electrode as a cathode. 2 The current efficiency is 86.1cd / A at a current density of 50mA / cm 2 The current efficiency at a current density of 1.5 GHz is 67.7 cd / A.

[0259] [Comparative Example 6]

[0260] Comparative compound (6) was purified by sublimation in the same manner as in the case of compound (4) of Example 1 to obtain a sublimate having an HPLC purity of 99.6%. An organic light-emitting device was produced in the same manner as in Example 1, except that the sublimate of Comparative Example 6 was used instead of the sublimate of Example 1.

[0261] The current efficiency of the obtained organic light-emitting device was measured using an ITO electrode as an anode and an Al electrode as a cathode. 2 The current efficiency is 85.5cd / A at a current density of 50mA / cm 2 The current efficiency at a current density of is 64.0 cd / A.

[0262] The structural formulas of comparative compounds are shown below.

[0263]

[0264] [Table 1]

[0265] Table 1

[0266]

[0267]

[0268] [Example 6]

[0269] Using the compound (4) described in Example 1, an organic light-emitting device having a structure of anode / hole injection layer / light-emitting layer / electron transport layer / cathode provided in this order on a substrate was produced as follows.

[0270] An ITO film having a thickness of 100 nm was formed on a glass substrate by sputtering to serve as an anode, and the resulting substrate was used as a transparent conductive support substrate (ITO substrate). The ITO substrate was washed with pure water, then with IPA, subjected to UV-ozone treatment, and then spin-coated to form a hole injection layer. The film formation conditions were as follows.

[0271] Coating solution: poly(3,4-ethylenedioxythiophene)-poly(styrene sulfonate) solution in water (PEDOT:PSS solution in water, available from Aldrich, conductivity: 1×10 -5 S / cm, compound concentration: 2.8 mass %)

[0272] Spin coating conditions: 3,000 rpm, 60 sec, in nitrogen atmosphere

[0273] Annealing conditions: 200°C, 1 hour, in nitrogen atmosphere

[0274] Film thickness: 40nm

[0275] Next, a light-emitting layer was formed by spin coating. The composition of the coating solution and film-forming conditions for forming the light-emitting layer were as follows.

[0276] Coating liquid: 6.0% by mass of compound (4)

[0277] EM37 94.0 mass%

[0278] Chlorobenzene 9900 mass%

[0279] Spin coating conditions: 3,000 rpm, 60 sec, in nitrogen atmosphere

[0280] Annealing conditions: 110°C, 10 minutes, in nitrogen atmosphere

[0281] Film thickness: 30nm

[0282] Finally, by 1×10 -5 The electron transport layer and the electrode layer were formed by vacuum evaporation using resistance heating in a vacuum chamber of 100 Pa. At this time, the electrodes were formed to have a thickness of 3 mm. 2 The film forming conditions are as follows.

[0283] Electrical transport layer: (50nm) TPBi

[0284] Metal electrode layer 1: (0.5nm) LiF

[0285] Metal electrode layer 2: (90nm) Al

[0286] Thereafter, in order not to cause degradation of the organic light emitting device due to moisture adsorption, the resulting structure was covered with a protective glass plate in a nitrogen atmosphere and sealed with an acrylic resin adhesive.

[0287] The current efficiency of the obtained organic light-emitting device was measured using an ITO electrode as an anode and an Al electrode as a cathode. 2 The current efficiency is 55.9cd / A at a current density of 50mA / cm 2 The current efficiency at a current density of 1.5 GHz is 45.4 cd / A.

[0288] [Example 7]

[0289] An organic light-emitting device was produced in the same manner as in Example 6, except that Compound (97) having an HPLC purity of 99.8% was used instead of Compound (4) in Example 6.

[0290] The current efficiency of the obtained organic light-emitting device was measured using an ITO electrode as an anode and an Al electrode as a cathode. 2 The current efficiency is 53.5cd / A at a current density of 50mA / cm 2 The current efficiency at a current density of 1.5 GHz is 44.2 cd / A.

[0291] [Reference Example 2]

[0292] An organic light-emitting device was produced in the same manner as in Example 6, except that Ir(ppy) 3 used in Reference Example 1 was used instead of Compound (4) in Example 6.

[0293] The current efficiency of the obtained organic light-emitting device was measured using an ITO electrode as an anode and an Al electrode as a cathode. 2 The current efficiency is 35.2cd / A at a current density of 50mA / cm 2 The current efficiency at a current density of 29.1 cd / A is 29.1 cd / A.

[0294] [Comparative Example 7]

[0295] An organic light-emitting device was produced in the same manner as in Example 6, except that the comparative compound (1) used in Comparative Example 1 was used instead of the compound (4) in Example 6.

[0296] [Comparative Example 8]

[0297] An organic light-emitting device was produced in the same manner as in Example 6, except that the comparative compound (3) used in Comparative Example 3 was used instead of the compound (4) in Example 6.

[0298] The current efficiency of the obtained organic light-emitting device was measured using an ITO electrode as an anode and an Al electrode as a cathode. 2 The current efficiency is 53.0cd / A at a current density of 50mA / cm 2 The current efficiency at a current density of 40.5 cd / A is 40.5 cd / A.

[0299] [Comparative Example 9]

[0300] An organic light-emitting device was produced in the same manner as in Example 6, except that the comparative compound (5) used in Comparative Example 5 was used instead of the compound (4) in Example 6.

[0301] The current efficiency of the obtained organic light-emitting device was measured using an ITO electrode as an anode and an Al electrode as a cathode. 2 The current efficiency is 56.8cd / A at a current density of 50mA / cm 2 The current efficiency at a current density of 42.3 cd / A is 42.3 cd / A.

[0302] [Table 2]

[0303] Table 2

[0304]

[0305] As described above, the organometallic complex according to the present invention is an organometallic complex having excellent decay characteristics in which the decrease rate of luminous efficiency at a second current density higher than the first current density relative to the luminous efficiency at the first current density is low.

[0306] The present invention is not limited to the above-described embodiments, and various changes and modifications can be made within the spirit and scope of the present invention. Therefore, in order to inform the public of the scope of the present invention, the following claims are made.

[0307] This application claims priority based on Japanese Patent Application No. 2021-112295 filed on July 6, 2021, the entire contents of which are incorporated herein by reference.

[0308] Description of Reference Numerals

[0309] 1 interlayer insulation layer

[0310] 2 Reflective electrode

[0311] 3 Insulation layer

[0312] 4 Organic compound layer

[0313] 5 Transparent Electrode

[0314] 6 protective layer

[0315] 7 Color Filters

[0316] 10 sub-pixels

[0317] 11 base plate

[0318] 12 Insulation layer

[0319] 13 Gate electrode

[0320] 14 Gate insulating film

[0321] 15 Semiconductor layer

[0322] 16 Drain electrode

[0323] 17 Source electrode

[0324] 18 Thin Film Transistors

[0325] 19 Insulation film

[0326] 20 contact holes

[0327] 21 Anode

[0328] 22 Organic compound layer

[0329] 23 cathode

[0330] 24 First protective layer

[0331] 25 Second protective layer

[0332] 26 Organic Light-Emitting Devices

[0333] 100 display devices

[0334] 1000 display devices

[0335] 1001 Top Cover

[0336] 1002 Flexible Printed Circuit

[0337] 1003 Touch Panel

[0338] 1004 Flexible Printed Circuit

[0339] 1005 Display Panel

[0340] 1006 Framework

[0341] 1007 Circuit Board

[0342] 1008 Batteries

[0343] 1009 lower cover

[0344] 1100 Camera Equipment

[0345] 1101 Viewfinder

[0346] 1102 rear display

[0347] 1103 operating unit

[0348] 1104 housing

[0349] 1200 Electronic Equipment

[0350] 1201 Display Unit

[0351] 1202 operating unit

[0352] 1203 housing

[0353] 1300 display devices

[0354] 1301 Framework

[0355] 1302 Display Unit

[0356] 1303 Base

[0357] 1310 Display Device

[0358] 1311 First Display

[0359] 1312 Second Display

[0360] 1313 Shell

[0361] 1314 Bend Point

[0362] 1400 Lighting Equipment

[0363] 1401 Housing

[0364] 1402 Light Source

[0365] 1403 Circuit Board

[0366] 1404 Optical Film

[0367] 1405 Light Diffuser

[0368] 1500 cars

[0369] 1501 Taillight

[0370] 1502 Window

[0371] 1503 Car body

[0372] 1600 Smart Glasses

[0373] 1601 Lens

[0374] 1602 Camera Equipment

[0375] 1603 Control Unit

[0376] 1610 Smart Glasses

[0377] 1611 Lens

[0378] 1612 Control Unit

Claims

1. An organometallic complex represented by any one of the following structural formulas (3) and (5):

2. An organic light-emitting device, characterized in that: It includes: a first electrode, a second electrode, and an organic compound layer disposed between the first electrode and the second electrode, Wherein, the organic compound layer comprises the organometallic complex according to claim 1.

3. The organic light-emitting device according to claim 2, wherein the organic compound layer is a light-emitting layer, and the organic compound layer further comprises a first charge transport layer disposed between the first electrode and the light-emitting layer, and a second charge transport layer disposed between the second electrode and the light-emitting layer. The first electrode is in contact with the first charge transport layer, and the second electrode is in contact with the second charge transport layer.

4. A display device, characterized in that: It includes: A plurality of pixels, at least one of the plurality of pixels comprises the organic light emitting device according to claim 2 or 3 and a transistor connected to the organic light emitting device.

5. A camera device, characterized in that: It includes: an optical unit including a plurality of lenses, an imaging device configured to receive light passing through the optical unit, and a display unit configured to display an image acquired by the imaging device, The display unit comprises the organic light-emitting device according to claim 2 or 3.

6. An electronic device, characterized in that: It includes: A display unit comprising the organic light emitting device according to claim 2 or 3, a housing provided with the display unit, and a communication unit disposed in the housing and communicating with the outside.

7. A lighting device, characterized in that: It includes: A light source comprising the organic light emitting device according to claim 2 or 3, and a light diffusion unit or an optical film configured to transmit light emitted from the light source.

8. A mobile object, characterized in that: It includes: A lighting unit comprising the organic light emitting device according to claim 2 or 3, and a body provided with the lighting unit.

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