Organic compounds and organic light-emitting elements

Abstract

To provide an organic light-emitting element having excellent luminous efficiency.SOLUTION: The present invention provides organic metal complex compounds represented by general formulae (1)-(3). In the general formulae (1)-(3), R1 and R2 are selected from H, D, a halogen atom, an alkyl group, a silyl group, an aryl group and the like; R3 is selected from D, a halogen atom, a cyano group, an alkyl group, an alkoxy group, a silyl group, an aryl group, a heterocyclic ring group, an amino group and the like; the substituents may together form a ring; R4 to R6 are selected from D, a halogen atom, a cyano group, an alkyl group, an alkoxy group, a silyl group, an aryl group, a heterocyclic ring group, an amino group and the like; m is an integer of 1-3 and n is an integer of 0-2; X is a bidentate ligand.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This invention relates to an organic compound and an organic light-emitting element using the same. [Background technology]

[0002] An organic light-emitting element (hereinafter sometimes referred to as an "organic electroluminescent element" or "organic EL element") is an electronic element having a pair of electrodes and an organic compound layer placed between these electrodes. By injecting electrons and holes from this pair of electrodes, excitons of the light-emitting organic compound in the organic compound layer are generated, and when these excitons return to the ground state, the organic light-emitting element emits light.

[0003] Recent advances in organic light-emitting devices are remarkable, and their features include low drive voltage, diverse emission wavelengths, fast response, and the ability to make light-emitting devices thinner and lighter.

[0004] Incidentally, there has been a great deal of activity in creating luminescent organic compounds. This is because creating compounds with excellent luminescence properties is crucial for providing high-performance organic light-emitting devices.

[0005] As a compound created to date, the following compound A-1 is described in Patent Document 1.

[0006] [ka] [Prior art documents] [Patent Documents]

[0007] [Patent Document 1] Special Publication No. 2012-522844 [Overview of the project] [Problems that the invention aims to solve]

[0008] Patent Document 1 describes Compound A-1 as a luminescent material, but Compound A-1 has problems with luminescence efficiency.

[0009] The present invention has been made in view of the above problems, and an object thereof is to provide an organometallic complex having excellent luminescence efficiency.

Means for Solving the Problems

[0010] The organometallic complex of the present invention is characterized by being represented by General Formulas (1) to (3). ​​​​​​​​​​​​​​​​

[0014] (In general formula (4) or (5), R9 to R 19 are each independently selected from the group consisting of a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group. Further, R 16 to R 19 may form a ring with each other.)

Advantages of the Invention

[0015] When the organometallic complex according to the present invention is used in an organic light-emitting device, an organometallic complex excellent in luminous efficiency can be provided.

Brief Description of the Drawings

[0016] [Figure 1] (a) It is a schematic cross-sectional view showing an example of a pixel of a display device according to an embodiment of the present invention. (b) It is a schematic cross-sectional view of an example of a display device using an organic light-emitting device according to an embodiment of the present invention.) [Figure 2] It is a schematic diagram showing an example of a display device according to an embodiment of the present invention. [Figure 3] (a) It is a schematic diagram showing an example of an imaging device according to an embodiment of the present invention. (b) It is a schematic diagram showing an example of a mobile device according to an embodiment of the present invention.) [Figure 4] (a) It is a schematic diagram showing an example of a display device according to an embodiment of the present invention. (b) It is a schematic diagram showing an example of a foldable display device.) [Figure 5] (a) It is a schematic diagram showing an example of a lighting device according to an embodiment of the present invention. (b) It is a schematic diagram showing an example of a moving body, an automobile, according to an embodiment of the present invention.) [Figure 6](a) A schematic diagram showing an example of a wearable device according to one embodiment of the present invention. (b) A schematic diagram showing an example of a wearable device according to one embodiment of the present invention, which includes an imaging device. [Figure 7] (a) A schematic diagram showing an example of an image forming apparatus according to one embodiment of the present invention. (b) A schematic diagram showing an example of an exposure light source for an image forming apparatus according to one embodiment of the present invention. (c) A schematic diagram showing an example of an exposure light source for an image forming apparatus according to one embodiment of the present invention. [Figure 8] This is a schematic diagram showing the structure of an organometallic complex and the three-dimensional structure of its ligand. [Modes for carrying out the invention]

[0017] In this specification, examples of halogen atoms include, but are not limited to, fluorine, chlorine, bromine, and iodine.

[0018] Examples of alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, secondary butyl, octyl, cyclohexyl, tert-pentyl, 3-methylpentan-3-yl, 1-adamantyl, and 2-adamantyl groups.

[0019] Examples of alkoxy groups include, but are not limited to, methoxy, ethoxy, propoxy, isopropyl, tertibtoxy, 2-ethyloctyloxy, and benzyloxy groups.

[0020] Examples of aryloxy groups include, but are not limited to, phenoxy, naphthoxy, and thienyloxy groups.

[0021] Examples of aryl groups include, but are not limited to, phenyl, naphthyl, indenyl, biphenyl, terphenyl, fluorenyl, phenanthryl, triphenylenyl, pyrenyl, anthranyl, perilenyl, chrysenyl, and fluoranthenyl groups.

[0022] Examples of heterocyclic groups include, but are not limited to, pyridyl, pyrimidyl, pyrazyl, triazyl, benzofuranyl, benzothiophenyl, dibenzofuranyl, dibenzothiophenyl, oxazolyl, oxadiazolyl, thiazolyl, thiadiazolyl, carbazolyl, acridinyl, and phenanthrolyl groups.

[0023] Examples of silyl groups include, but are not limited to, trimethylsilyl and triphenylsilyl groups.

[0024] Examples of amino groups include, but are not limited to, N-methylamino group, N-ethylamino group, N,N-dimethylamino group, N,N-diethylamino group, N-methyl-N-ethylamino group, N-benzylamino group, N-methyl-N-benzylamino group, N,N-dibenzylamino group, anilino group, N,N-diphenylamino group, N,N-dinaphthylamino group, N,N-difluorenylamino group, N-phenyl-N-tolylamino group, N,N-ditolylamino group, N-methyl-N-phenylamino group, N,N-dianisorylamino group, N-mesityl-N-phenylamino group, N,N-dimesitylamino group, N-phenyl-N-(4-tert-butylphenyl)amino group, N-phenyl-N-(4-trifluoromethylphenyl)amino group, N-piperidyl group, carbazolyl group, acridyl group, trimethylamino group, and triphenylamino group.

[0025] Examples of substituents that the alkyl, alkoxy, amino, aryl, heterocyclic, aryloxy, and silyl groups may further have include, but are not limited to, deuterium, alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, and tert-butyl groups, aralkyl groups such as benzyl groups, aryl groups such as phenyl and biphenyl groups, heterocyclic groups such as pyridyl and pyrrolyl groups, amino groups such as dimethylamino, diethylamino, dibenzylamino, diphenylamino, and ditolylamino groups, alkoxy groups such as methoxy, ethoxy, and propoxy groups, aryloxy groups such as phenoxy groups, halogen atoms such as fluorine, chlorine, bromine, and iodine, and cyano groups.

[0026] (1) Organometallic complexes First, the organometallic complex according to this embodiment will be described.

[0027] The organometallic complexes of the present invention are compounds represented by general formulas (1) to (3). In this specification, coordinate bonds are represented by arrows or straight lines, and bonds other than coordinate bonds are represented by straight lines. Furthermore, azabenzofluorene refers to a ring structure in which one carbon atom in benzofluorene is substituted with a nitrogen atom.

[0028] [ka]

[0029] ≪R1 to R6≫ In general formulas (1) to (3), R1 and R2 are independently selected from the group consisting of a hydrogen atom, a deuterium atom, a halogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted silyl group, and a substituted or unsubstituted aryl group.

[0030] R3 represents a substituent that substitutes for the phenyl group and is independently selected from the group consisting of a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, or a substituted or unsubstituted amino group. The substituents may form a ring with each other.

[0031] R4 to R6 represent substituents that substitute for the ring structure constituting azabenzofluorene, and are independently selected from the group consisting of a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, or a substituted or unsubstituted amino group.

[0032] In organometallic complexes represented by general formulas (1) to (3), R1 and R2 are preferably substituents, more preferably halogen atoms or substituted or unsubstituted alkyl groups having 1 to 4 carbon atoms, and particularly preferably methyl groups or fluorine atoms.

[0033] Furthermore, in organometallic complexes represented by general formulas (1) to (3), it is preferable that at least one of R3 or R4 is a substituent, more preferably that the substituent is a tertiary alkyl group having 4 to 10 carbon atoms, and particularly preferably that the tertiary alkyl group is a tertiary butyl group. It is also particularly preferable that R3 has a substituent.

[0034] In organometallic complexes represented by general formulas (1) to (3), the ring structure formed by multiple R3 atoms is preferably a fused ring structure of four or fewer rings, and the fused ring structure preferably contains at least one atom from among carbon atoms, nitrogen atoms, sulfur atoms, oxygen atoms, phosphorus atoms, selenium atoms, or tellurium atoms.

[0035] Furthermore, in General Formulas (1) to (3), a plurality of R3s may form any of the following ring structures of General Formulas (10) to (20). However, * represents the bonding position to the azabenzofluorene ring.

[0036]

Chemical Formula

[0037] ≪R7≫ In General Formulas (10) to (20), R7 is independently selected from the group consisting of a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group.

[0038] ≪Y≫ Y is either an oxygen atom, a sulfur atom, or C(R 20 )(R 21 ).

[0039] ≪R 20 and R 21 ≫ In General Formulas (10) to (20), R 20 and R 21 represent a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted silyl group, or a substituted or unsubstituted aryl group.

[0040] ≪m, n≫ In General Formulas (1) to (3), m represents an integer from 1 to 3, and n represents an integer from 0 to 2. However, m + n = 3.

[0041] ≪X≫ In General Formulas (1) to (3), X represents a bidentate ligand, and the partial structure Ir(X)n is either of the structures shown in the following General Formula (4) or (5). Also, the three ligands coordinated to the iridium atom may be the same or different from each other.

[0042] [ka]

[0043] ≪R9 to R 19 ≫ In general formula (4) or (5), R9 to R 19 Each of these is independently selected from the group consisting of a hydrogen atom, a deuterium atom, a halogen atom, a cyano group, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted silyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group. 16 ~R 19 The substituents may form a ring with each other.

[0044] The organometallic complexes represented by general formulas (1) to (3) have the following characteristics. (1-1) The ligand has an azabenzofluorene ring, resulting in a high emission quantum yield. (1-2) The ligand has an azabenzofluorene ring, resulting in high hole transport capability.

[0045] The following describes these features.

[0046] (1-1) The ligand has an azabenzofluorene ring, resulting in a high emission quantum yield.

[0047] Iridium complexes represented by general formulas (1) to (3) exhibit a large transition dipole moment and high emission quantum yield due to the coordination of an azabenzofluorene ring to the iridium atom. Furthermore, as shown in Table 1, compounds 1 and 2, which have an azabenzofluorene ring as a ligand, were found to have higher emission quantum yields compared to comparative compound 1, which also has an azafluorene ring as a ligand. Compounds 1 and 2 are the exemplary compounds C-1 and E-1, respectively, described later. It is thought that compounds 1 and 2 have a larger transition dipole moment and higher emission quantum yield because they have one more benzene ring fused compared to comparative compound 1. The quantum yield was measured using an absolute PL quantum yield analyzer (C9920-02) manufactured by Hamamatsu Photonics, in a diluted toluene solution. The quantum yield is expressed as a relative value, with the quantum yield of compound 1 set to 1.0.

[0048] [Table 1]

[0049] (1-2) Having an azabenzofluorene ring as a ligand gives it high hole transport capability.

[0050] Iridium complexes represented by general formulas (1) to (3) exhibit high hole transport properties due to the presence of azabenzofluorene rings in their ligands. This is thought to be due to the structure, which allows the azabenzofluorene rings of the ligands to easily overlap, facilitating hole hopping between ligands.

[0051] Furthermore, the compounds of the present invention preferably have the following characteristics. (1-3) When R1 and R2 are substituents, the emission exhibits high color purity. (1-4) If at least one of the substituents of R3 or R4 is a tertiary alkyl group, the sublimation properties are improved.

[0052] The following describes these features.

[0053] (1-3) When R1 and R2 are substituents, the emission exhibits high color purity.

[0054] In iridium complexes represented by general formulas (1) to (3), as shown in Figure 8, the two substituents R1 and R2 substituted at the 11-position of the azabenzofluorene ring are positioned so as to sandwich the hydrogen atom on the phenyl group side. Because the hydrogen atom on the phenyl group side is repelled by the substituents on both sides of the azabenzofluorene ring, the dihedral angle between the phenyl group and the azabenzofluorene ring is fixed, and vibrations due to the rotation of the two rings can be suppressed. As a result, the emission spectrum of the iridium complex exhibits a narrow full width at half maximum and high color purity. To further obtain the above effect, R1 and R2 are preferably substituents, more preferably halogen atoms or substituted or unsubstituted alkyl groups having 1 to 4 carbon atoms, and particularly preferably methyl groups or fluorine atoms.

[0055] Furthermore, in general formulas (1) to (3), it is preferable to form a ring structure in which multiple R3 atoms are of general formulas (11), (12), (14), (15), (17), (19), or (20). This is because the above effect is particularly large when the two substituents R1 and R2 substituted at the 11-position of the azabenzofluorene ring are positioned to sandwich the hydrogen atom on the phenyl group side.

[0056] (1-4) If at least one of the substituents of R3 or R4 is a substituent, the sublimation properties are improved.

[0057] Iridium complexes represented by general formulas (1) to (3) have the characteristics described in (1-1) to (1-3) above due to having an azabenzofluorene ring as a ligand. On the other hand, the presence of a condensed polycyclic group can result in a large molecular weight and low sublimation properties. Specifically, this can lead to high temperatures during sublimation purification or decomposition of part of the complex after sublimation purification. Therefore, it is preferable that at least one of R3 or R4 is a substituent, more preferably a tertiary alkyl group having 4 to 10 carbon atoms, and particularly preferably a tertiary butyl group. This suppresses molecular stacking between complexes and lowers the sublimation temperature. Tertiary alkyl groups have a large excluded volume effect, so their effect in suppressing molecular stacking is particularly significant. Furthermore, being a tertiary alkyl group can reduce radical cleavage of the hydrogen at the benzyl position at high temperatures.

[0058] Table 2 shows the bond dissociation energies of carbon-hydrogen bonds.

[0059] [Table 2]

[0060] A higher bond dissociation energy indicates a stronger bond, while a lower value indicates a weaker bond. Therefore, the carbon-hydrogen bond at the benzyl position is weaker than other bonds. This is because when a hydrogen atom is removed from the benzyl group and becomes a radical, the resonance of π electrons with the adjacent benzene ring stabilizes the radical. Consequently, the carbon-hydrogen bond at the benzyl position is weaker than other bonds. Therefore, it is preferable to have a molecular structure that does not contain a structure like the benzyl position, as this results in a compound where the carbon-hydrogen bond is less likely to be broken.

[0061] Specific examples of organometallic complexes according to the present invention are shown below, but are of course not limited to these.

[0062] [ka]

[0063]

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[0074] Examples of compounds belonging to group C are organometallic complexes represented by general formula (1). By having an azabenzofluorene ring as a ligand, the emission quantum yield can be improved.

[0075] The exemplary compounds belonging to group D are organometallic complexes represented by general formula (1), wherein at least one of R3 or R4 is a tertiary alkyl group. The presence of a tertiary alkyl group suppresses molecular stacking, improving sublimation and reducing concentration quenching in the luminescent layer.

[0076] Examples of compounds belonging to group E are those shown in general formula (2). By having an azabenzofluorene ring as a ligand, the emission quantum yield can be improved.

[0077] The exemplary compounds belonging to group F are compounds represented by general formula (2), in which at least one of R3 or R4 is a tertiary alkyl group. Having a tertiary alkyl group suppresses molecular stacking, improving sublimation and reducing concentration quenching in the luminescent layer.

[0078] Examples of compounds belonging to group G are those shown in general formula (3). By having an azabenzofluorene ring as a ligand, the emission quantum yield can be improved.

[0079] The exemplary compounds belonging to group H are compounds represented by general formula (3) and in which at least one of R3 or R4 is a tertiary alkyl group. Having a tertiary alkyl group suppresses molecular stacking, improving sublimation and reducing concentration quenching in the luminescent layer.

[0080] (2) Characteristics of organic light-emitting diodes The organic light-emitting element of the present invention comprises a first electrode, a light-emitting layer, and a second electrode in this order. The light-emitting layer has an organometallic complex represented by general formulas (1) to (3) (hereinafter sometimes referred to as "dopant material") and a first compound (hereinafter sometimes referred to as "host material"), and has the following characteristics. (2-1) Because the host material is a hydrocarbon compound, the interaction between the dopant material and the host material is strong, and energy transfer is easy. (2-2) The effect of (2-1) above promotes hole transport hopping between the dopant material and the host material, thereby improving hole transportability in the light-emitting layer.

[0081] The following describes these features.

[0082] (2-1) Because the host material is a hydrocarbon compound, the interaction between the dopant material and the host material is strong, and energy transfer is easy.

[0083] The organometallic complexes represented by general formulas (1) to (3) have an azabenzofluorene ring, which is a condensed polycyclic group consisting of four rings, as a ligand. The host material is preferably a compound having a condensed polycyclic group, and more preferably a compound having a condensed polycyclic group consisting of a hydrocarbon. Having a condensed polycyclic group in both the ligand of the organometallic complex and the host material facilitates ππ interactions and makes energy transfer from the host material to the dopant material easier.

[0084] Here, it is known that the triplet energy used in phosphorescent light-emitting devices is transferred via the Dexter mechanism. In the Dexter mechanism, energy is transferred through contact between molecules. That is, the intermolecular distance between the host material and the guest material is shortened by ππ interactions, allowing for efficient energy transfer from the host material to the guest material.

[0085] Due to the above effects, triplet excitons generated in the host material are quickly consumed for light emission, resulting in a highly efficient organic light-emitting device. Furthermore, material degradation caused by high-energy triplet excited states resulting from the further excitation of triplet excitons not used for light emission can be reduced, thus improving the operating durability characteristics of the organic light-emitting device.

[0086] (2-2) The effect of (2-1) above promotes hole transport hopping between the dopant material and the host material, thereby improving hole transportability in the light-emitting layer.

[0087] Organometallic complexes represented by general formulas (1) to (3) tend to have a higher HOMO level (closer to the vacuum level) than the host material due to the effect of having an azabenzofluorene ring in the ligand. Holes injected from the hole transport layer are transported by the host material, but the holes are repeatedly trapped and detrapped between the host material and the dopant material during transport. In this case, it is preferable that similar skeletons are used for the host material and the dopant material. In this case, the overlap between the condensed rings of the host material and the dopant material is strong, and hole movement between the host material and the dopant material is carried out efficiently. As a result, the voltage rise in the light-emitting layer is suppressed, and an organic light-emitting element with good drive durability characteristics at low voltage is provided.

[0088] Furthermore, the organic light-emitting element of the present invention preferably has the following characteristics. (2-3) The light-emitting layer further contains a second compound (hereinafter sometimes referred to as the "assist material"), and by using a material in which the LUMO level of the assist material is higher than that of the host material (further from the vacuum level), the light-emitting efficiency of the light-emitting device is improved.

[0089] The following explains this feature.

[0090] (2-3) The light-emitting layer further contains a second compound (assist material), and by using a material in which the LUMO level of the assist material is higher (further from the vacuum level) than the LUMO level of the host material, the light-emitting efficiency of the light-emitting device is improved.

[0091] Organometallic complexes represented by general formulas (1) to (3) promote hole injection into the light-emitting layer. Therefore, to ensure a balanced injection of electrons and holes into the light-emitting layer, it is preferable to promote electron injection into the light-emitting layer. When the host material is a compound composed of hydrocarbons, it has a broad band cap. As a result, the host material has a high LUMO level, which may make it difficult for electrons to be injected from the electron transport layer or hole blocking layer. Therefore, it is preferable to include an assist material to facilitate electron injection into the light-emitting layer. Furthermore, it is preferable that the LUMO level of the assist material is lower than that of the host material. This improves the injection of both holes and electrons into the light-emitting layer, maintaining a carrier balance in the light-emitting layer and providing a highly efficient light-emitting element.

[0092] As described above, the element of this embodiment exhibits the effect of the dopant material in the light-emitting layer promoting hole injection and confining holes in the light-emitting layer through hole trapping. This reduces the injection of holes from the light-emitting layer to the hole-blocking layer and electron-transporting layer, thereby reducing the degradation of the hole-blocking layer and electron-transporting layer by holes.

[0093] Furthermore, the assist material, which has a lower LUMO level than the host material, promotes electron injection and exhibits the effect of confining electrons in the light-emitting layer through electron trapping. This reduces the injection of electrons from the light-emitting layer to the electron-blocking layer and hole transport layer, thereby reducing the degradation of the electron-blocking layer and hole transport layer by electrons.

[0094] (3) Host material The host material of the present invention has a lower minimum excitation triplet energy (T1) than the dopant material. Furthermore, it is preferable that it has the following characteristics. (3-1) Preferably having at least one skeleton of triphenylene, naphthalene, phenanthrene, chrysene, or fluorantene. (3-2) Does not have SP3 carbon.

[0095] The following describes these features.

[0096] (3-1) Preferably having at least one skeleton of triphenylene, naphthalene, phenanthrene, chrysene, or fluorantene.

[0097] Organometallic complexes represented by general formulas (1) to (3) have an azabenzofluorene ring as a ligand. The azabenzofluorene ring has a highly planar structure. As described in (2-1) and (2-2) above, the dopant material and the host material interact, so it is preferable that the host material also has a highly planar structure. This is because having a highly planar structure allows highly planar parts to approach each other through interaction. More specifically, the fluorene part of the dopant material and the planar part of the host material can approach each other more easily. As a result, it can be expected that the intermolecular distance between the dopant material and the host material will be shortened. These effects lead to the effect of increased energy transfer efficiency described in (2-1).

[0098] In this context, examples of highly planar structures include condensed polycyclic groups with three or more rings, and compounds containing condensed polycyclic groups having hydrocarbons, such as triphenylene, naphthalene, phenanthrene, chrysene, and fluorantene, are preferred.

[0099] (3-2) Preferably, it does not have SP3 carbon.

[0100] As described above (3-1), the dopant material of this embodiment is a compound characterized by improved interaction and luminescence properties when the distance to the host material is improved. The host material is even more preferable if it does not contain SP3 carbon, as this allows the distance to the dopant material to be shortened.

[0101] Specific examples of host materials are shown below, but of course, they are not the only ones.

[0102] [ka]

[0103] [ka]

[0104] The above example compounds are compounds that have at least one of the following in their skeleton: triphenylene, naphthalene, phenanthrene, chrysene, or fluorantene, and do not have an SP3 carbon. Therefore, these compounds can get closer to the dopant material, resulting in strong interactions and good energy transfer to the dopant material, making them suitable host materials. Among these, compounds with triphenylene in their skeleton are particularly preferred due to their high planarity.

[0105] (4) Assist materials The T1 of the assist material of the present invention is greater than or equal to the T1 of the dopant material. Furthermore, it is preferable that the compound has at least one of the following structures.

[0106] [ka]

[0107] (X represents an oxygen atom, a sulfur atom, or a substituted or unsubstituted carbon atom.)

[0108] The above structure is effective because it has an electron-withdrawing group and can reduce the LUMO level of the assisting material. Organometallic complexes represented by general formulas (1) to (3) have a low HOMO level, making them prone to trapping holes. On the other hand, they also have a low LUMO level, making them less prone to trapping electrons. Therefore, including an assisting material with a high LUMO level in the light-emitting layer makes it easier to trap electrons in the light-emitting layer. As a result, it provides a device with an appropriate carrier balance, resulting in a highly efficient and long-life device.

[0109] Furthermore, the above structure may be unsubstituted or substituted. Also, the carbon atom represented by X may be unsubstituted or substituted. Examples of substituents include halogen atoms, alkyl groups, alkoxy groups, aryloxy groups, aryl groups, heterocyclic groups, silyl groups, amino groups, and the like.

[0110] Specific examples of assisting materials are shown below, but of course, they are not the only ones.

[0111] [ka]

[0112] [ka]

[0113] The concentration of the assisting material is preferably 0.1% by weight or more and 45% by weight or less of the entire light-emitting layer, and more preferably 5% by weight or more and 40% by weight or less.

[0114] (5) Details of organic light-emitting devices Next, the organic light-emitting element of this embodiment will be described. The organic light-emitting element of this embodiment has at least a first electrode, a second electrode, and an organic compound layer disposed between these electrodes. One of the first electrode and the second electrode is the anode and the other is the cathode. In the organic light-emitting element of this embodiment, the organic compound layer may be a single layer or a laminate consisting of multiple layers, as long as it has a light-emitting layer. If the organic compound layer is a laminate consisting of multiple layers, the organic compound layer may have, in addition to the light-emitting layer, a hole injection layer, a hole transport layer, an electron blocking layer, a hole-exciton blocking layer, an electron transport layer, an electron injection layer, etc. Furthermore, the light-emitting layer may be a single layer or a laminate consisting of multiple layers.

[0115] In the organic light-emitting element of this embodiment, at least one layer of the organic compound layer contains the organometallic complex according to this embodiment. Specifically, the organic compound according to this embodiment is included in any of the above-mentioned light-emitting layer, hole implantation layer, hole transport layer, electron blocking layer, hole-exciton blocking layer, electron transport layer, electron implantation layer, etc. The organic compound according to this embodiment is preferably included in the light-emitting layer.

[0116] In the organic light-emitting element of this embodiment, when the organic compound according to this embodiment is included in the light-emitting layer, the light-emitting layer may consist only of the organic compound according to this embodiment, or it may consist of the organometallic complex according to this embodiment and other compounds. Here, when the light-emitting layer consists of the organometallic complex according to this embodiment and other compounds, the organic compound according to this embodiment may be used as a host or a guest in the light-emitting layer. It may also be used as an assist material that can be included in the light-emitting layer. Here, the host is the compound with the largest mass ratio among the compounds constituting the light-emitting layer. The guest is a compound with a smaller mass ratio than the host among the compounds constituting the light-emitting layer, and is responsible for the main light emission. The assist material is a compound with a smaller mass ratio than the host among the compounds constituting the light-emitting layer, and assists the light emission of the guest. The assist material is also called the second host. The host material can also be called the first compound, and the assist material can be called the second compound.

[0117] When the organic compound according to this embodiment is used as a guest in the light-emitting layer, the concentration of the guest is preferably 0.01% by mass or more and 30% by mass or less, and more preferably 2% by mass or more and 20% by mass or less, relative to the entire light-emitting layer.

[0118] The inventors conducted various studies and found that when the organic compound according to this embodiment is used as a host or guest for the light-emitting layer, particularly as a guest for the light-emitting layer, a device can be obtained that exhibits high efficiency, high brightness, and extremely high durability. This light-emitting layer may be a single layer or a multi-layer, and it is also possible to mix the light emission with the red light emission of this embodiment by including a light-emitting material having another light emission color. A multi-layer means a state in which one light-emitting layer and another light-emitting layer are stacked. In this case, the light emission color of the organic light-emitting element is not limited to red. More specifically, it may be white or an intermediate color. In the case of white, the other light-emitting layer emits a color other than red, i.e., blue or green. Furthermore, the film is formed by vapor deposition or coating. Details of this will be explained in detail in the examples described later.

[0119] The organometallic complex according to this embodiment can be used as a constituent material for organic compound layers other than the light-emitting layer constituting the organic light-emitting device of this embodiment. Specifically, it may be used as a constituent material for electron transport layers, electron injection layers, hole transport layers, hole injection layers, hole blocking layers, etc. In this case, the light-emitting color of the organic light-emitting device is not limited to red. More specifically, it may be white light or an intermediate color.

[0120] In addition to the organic compounds according to this embodiment, conventionally known low-molecular-weight and high-molecular-weight hole-injecting or hole-transporting compounds, host compounds, luminescent compounds, electron-injecting or electron-transporting compounds, etc., can be used together as needed. Examples of these compounds are listed below.

[0121] As hole-implantation transport materials, materials with high hole mobility are preferred to facilitate hole injection from the anode and to transport the injected holes to the light-emitting layer. Furthermore, materials with a high glass transition temperature are preferred to suppress deterioration of the film quality, such as crystallization, in the organic light-emitting element. Examples of low-molecular-weight and high-molecular-weight materials with hole-implantation transport properties include triarylamine derivatives, arylcarbazole derivatives, phenylenediamine derivatives, stilbene derivatives, phthalocyanine derivatives, porphyrin derivatives, poly(vinylcarbazole), poly(thiophene), and other conductive polymers. Moreover, the above-mentioned hole-implantation transport materials are also suitably used in electron-blocking layers. Specific examples of compounds used as hole-implantation transport materials are shown below, but are not limited to these.

[0122] [ka]

[0123] Among the hole transport materials listed, HT16 to HT18 can reduce the driving voltage when used in the layer in contact with the anode. HT16 is widely used in organic light-emitting devices. HT2, HT3, HT4, HT5, HT6, HT10, and HT12 may be used in the organic compound layer adjacent to HT16. Furthermore, multiple materials may be used in a single organic compound layer.

[0124] In addition to the luminescent dopant of the present invention, other luminescent dopants may also be used.

[0125] Examples include fused ring compounds (e.g., fluorene derivatives, naphthalene derivatives, pyrene derivatives, perylene derivatives, tetracene derivatives, anthracene derivatives, rubrene, etc.), quinacridone derivatives, coumarin derivatives, stilbene derivatives, organoaluminum complexes such as tris(8-quinolinolate)aluminum, iridium complexes, platinum complexes, rhenium complexes, copper complexes, europium complexes, ruthenium complexes, and polymer derivatives such as poly(phenylenevinylene) derivatives, poly(fluorene) derivatives, and poly(phenylene) derivatives.

[0126] The following are some specific examples of compounds used as luminescent materials, but of course, they are not the only ones.

[0127] [ka]

[0128] [ka]

[0129] When the luminescent material is a hydrocarbon compound, it is preferable because it can reduce the decrease in luminescence efficiency due to excyplex formation and the decrease in color purity due to changes in the emission spectrum of the luminescent material. A hydrocarbon compound is a compound composed only of carbon and hydrogen, and among the example compounds above, BD7, BD8, GD5 to GD9, and RD1 fall into this category.

[0130] When the light-emitting material is a condensed polycyclic material containing a five-membered ring, it is even more preferable because its ionization potential is high, making it less susceptible to oxidation and providing a device with a long and durable lifespan. BD7, BD8, GD5 to GD9, and RD1 are examples of this.

[0131] Examples of host materials or assist materials included in the light-emitting layer include aromatic hydrocarbon compounds or their derivatives, as well as carbazole derivatives, dibenzofuran derivatives, dibenzothiophene derivatives, organoaluminum complexes such as tris(8-quinolinolate)aluminum, and organoberylium complexes.

[0132] The following are some specific examples of compounds, but of course, they are not the only ones.

[0133] [ka]

[0134] When the host material is a hydrocarbon compound, the compound of the present invention is more likely to trap electrons and holes, thus greatly improving efficiency, which is preferable. A hydrocarbon compound is a compound composed only of carbon and hydrogen, and among the example compounds above, EM1 to EM12 and EM16 to EM27 correspond to this.

[0135] As electron-transporting materials, any material capable of transporting electrons injected from the cathode to the light-emitting layer can be arbitrarily selected, taking into consideration the balance with the hole mobility of the hole-transporting material. Examples of materials with electron-transporting properties include oxadiazole derivatives, pyrazine derivatives, triazole derivatives, triazine derivatives, quinoline derivatives, quinoxaline derivatives, phenanthroline derivatives, organoaluminum complexes, and fused ring compounds (e.g., fluorene derivatives, naphthalene derivatives, chrysene derivatives, anthracene derivatives, etc.). Furthermore, the above electron-transporting materials are also suitably used in the hole-blocking layer.

[0136] The following are specific examples of compounds used as electron transport materials, but of course, they are not the only ones.

[0137] [ka]

[0138] Electron-injectable materials can be arbitrarily selected from those that allow for easy electron injection from the cathode, taking into consideration the balance with hole injection properties. Organic compounds include n-type dopants and reducing dopants. Examples include alkali metal compounds such as lithium fluoride, lithium complexes such as lithium quinolinol, benzimidazolidene derivatives, imidazolidene derivatives, fluvalene derivatives, and acridine derivatives.

[0139] <Configuration of an organic light-emitting element> An organic light-emitting element is provided on a substrate by forming an insulating layer, a first electrode, an organic compound layer, and a second electrode. A protective layer, a color filter, a microlens, etc., may be provided on the cathode. If a color filter is provided, a planarization layer may be provided between it and the protective layer. The planarization layer can be made of acrylic resin or the like. The same applies when a planarization layer is provided between the color filter and the microlens.

[0140] [substrate] Examples of substrates include quartz, glass, silicon wafers, resins, and metals. The substrate may also be equipped with switching elements such as transistors and wiring, and an insulating layer may be provided on top of them. The insulating layer can be made of any material that allows for the formation of contact holes between it and the first electrode, while ensuring insulation from wiring that is not connected. For example, resins such as polyimide, silicon oxide, and silicon nitride can be used.

[0141] [electrode] A pair of electrodes can be used. The pair of electrodes may be an anode and a cathode. When an electric field is applied in the direction in which the organic light-emitting element emits light, the electrode with the higher potential is the anode, and the other is the cathode. Alternatively, the electrode that supplies holes to the light-emitting layer can be the anode, and the electrode that supplies electrons can be the cathode.

[0142] For the anode, materials with the largest possible work function are preferable. For example, elemental metals such as gold, platinum, silver, copper, nickel, palladium, cobalt, selenium, vanadium, and tungsten, or mixtures containing these, or alloys combining them, as well as metal oxides such as tin oxide, zinc oxide, indium oxide, tin-indium oxide (ITO), and zinc-indium oxide can be used. Conductive polymers such as polyaniline, polypyrrole, and polythiophene can also be used.

[0143] These electrode materials may be used individually or in combination of two or more types. Furthermore, the anode may consist of a single layer or multiple layers.

[0144] When used as a reflective electrode, materials such as chromium, aluminum, silver, titanium, tungsten, molybdenum, or alloys or laminates thereof can be used. It is also possible to use the above materials as a reflective film without serving as an electrode. Furthermore, when used as a transparent electrode, oxide transparent conductive layers such as indium tin oxide (ITO) or indium zinc oxide can be used, but are not limited to these. Photolithography can be used to form the electrodes.

[0145] On the other hand, materials with a small work function are preferred for the cathode. Examples include alkali metals such as lithium, alkaline earth metals such as calcium, and elemental metals or mixtures containing aluminum, titanium, manganese, silver, lead, and chromium. Alternatively, alloys combining these elemental metals can also be used. For example, magnesium-silver, aluminum-lithium, aluminum-magnesium, silver-copper, and zinc-silver can be used. Metal oxides such as indium tin oxide (ITO) can also be used. These electrode materials may be used individually or in combination of two or more. The cathode may also be a single-layer or multi-layer structure. Among these, silver is preferred, and a silver alloy is even more preferred to reduce silver aggregation. The alloy ratio is not important as long as silver aggregation is reduced. For example, the ratio of silver to other metals may be 1:1, 3:1, etc.

[0146] The cathode may be a top-emission element using an oxide conductive layer such as ITO, or a bottom-emission element using a reflective electrode such as aluminum (Al), and is not particularly limited. The method for forming the cathode is not particularly limited, but using DC and AC sputtering methods is more preferable because it provides good film coverage and makes it easier to reduce resistance.

[0147] [Organic compound layer] The organic compound layer may be formed as a single layer or as multiple layers. If there are multiple layers, they may be called a hole injection layer, a hole transport layer, an electron blocking layer, an emissive layer, a hole blocking layer, an electron transport layer, or an electron injection layer, depending on their function. The organic compound layer is mainly composed of organic compounds, but may also contain inorganic atoms and inorganic compounds. For example, it may contain copper, lithium, magnesium, aluminum, iridium, platinum, molybdenum, zinc, etc. The organic compound layer may be placed between the first electrode and the second electrode, or it may be placed in contact with the first electrode and the second electrode.

[0148] [Protective layer] A protective layer may be provided on the cathode. For example, by bonding glass with a desiccant to the cathode, the intrusion of water and other substances into the organic compound layer can be reduced, thereby reducing the occurrence of display defects. In another embodiment, a passivation film such as silicon nitride may be provided on the cathode to reduce the intrusion of water and other substances into the organic compound layer. For example, after forming the cathode, it may be transported to another chamber without breaking the vacuum and a silicon nitride film with a thickness of 2 μm may be formed by the CVD method to serve as a protective layer. A protective layer may also be provided using atomic deposition (ALD) after the film formation by the CVD method. The material of the film formed by the ALD method is not limited, but may be silicon nitride, silicon oxide, aluminum oxide, etc. Silicon nitride may be further formed on the film formed by the ALD method by the CVD method. The film formed by the ALD method may have a thinner film thickness than the film formed by the CVD method. Specifically, it may be 50% or less, or even 10% or less.

[0149] [Color Filter] A color filter may be provided on top of the protective layer. For example, a color filter that takes into account the size of the organic light-emitting element may be provided on a separate substrate and bonded to the substrate on which the organic light-emitting element is provided, or a color filter may be patterned on the protective layer as described above using photolithography technology. The color filter may be made of polymer.

[0150] [Planarization layer] A planarizing layer may be provided between the color filter and the protective layer. The planarizing layer is provided to reduce the unevenness of the layer below. It may also be called a material resin layer without limiting its purpose. The planarizing layer may be composed of an organic compound, which may be low molecular weight or high molecular weight, but high molecular weight is preferred.

[0151] The planarization layer may be provided above or below the color filter, and its constituent materials may be the same or different. Specifically, examples include polyvinylcarbazole resin, polycarbonate resin, polyester resin, ABS resin, acrylic resin, polyimide resin, phenolic resin, epoxy resin, silicone resin, urea resin, etc.

[0152] [Microlens] An organic light-emitting device may have optical elements such as microlenses on its light-emitting side. Microlenses may be made of acrylic resin, epoxy resin, or the like. Microlenses may be used to increase the amount of light extracted from the organic light-emitting device or to control the direction of the extracted light. Microlenses may have a hemispherical shape. If they have a hemispherical shape, among the tangents tangent to the hemisphere, there is a tangent parallel to the insulating layer, and the point of contact between that tangent and the hemisphere is the vertex of the microlens. The vertex of the microlens can be similarly determined in any cross-sectional view. That is, among the tangents tangent to the semicircle of the microlens in the cross-sectional view, there is a tangent parallel to the insulating layer, and the point of contact between that tangent and the semicircle is the vertex of the microlens.

[0153] Furthermore, the midpoint of a microlens can also be defined. In the cross-section of a microlens, a line segment can be imagined from the point where one arc ends to the point where another arc ends, and the midpoint of this line segment can be called the midpoint of the microlens. The cross-section used to determine the vertices and midpoints may be a cross-section perpendicular to the insulating layer.

[0154] [Opposite substrate] A counter substrate may be provided on the planarized layer. The counter substrate is called a counter substrate because it is provided in a position corresponding to the aforementioned substrate. The constituent material of the counter substrate may be the same as that of the aforementioned substrate. The counter substrate may be the second substrate if the aforementioned substrate is referred to as the first substrate.

[0155] [Organic layer] The organic compound layer (hole injection layer, hole transport layer, electron blocking layer, light-emitting layer, hole blocking layer, electron transport layer, electron injection layer, etc.) constituting the organic light-emitting element according to one embodiment of the present invention is formed by the method shown below.

[0156] The organic compound layer constituting the organic light-emitting element according to one embodiment of the present invention can be formed using a dry process such as vacuum deposition, ionization deposition, sputtering, or plasma deposition. Alternatively, instead of a dry process, a wet process can be used in which the layer is formed by dissolving the compound in a suitable solvent and applying a known coating method (e.g., spin coating, dipping, casting, LB method, inkjet method, etc.).

[0157] When layers are formed using methods such as vacuum deposition or solution coating, crystallization is less likely to occur, resulting in excellent stability over time. Furthermore, when forming films using coating methods, it is possible to combine the film with an appropriate binder resin.

[0158] Examples of the binder resins mentioned above include, but are not limited to, polyvinylcarbazole resin, polycarbonate resin, polyester resin, ABS resin, acrylic resin, polyimide resin, phenolic resin, epoxy resin, silicone resin, and urea resin.

[0159] Furthermore, these binder resins may be used individually as homopolymers or copolymers, or as a mixture of two or more types. Additionally, known additives such as plasticizers, antioxidants, and UV absorbers may be used in combination as needed.

[0160] [Pixel circuit] The light-emitting device may have a pixel circuit connected to a light-emitting element. The pixel circuit may be an active-matrix type that independently controls the light emission of a first light-emitting element and a second light-emitting element. The active-matrix type circuit may be voltage-programmed or current-programmed. The drive circuit has a pixel circuit for each pixel. The pixel circuit may have a light-emitting element, a transistor that controls the light emission brightness of the light-emitting element, a transistor that controls the light emission timing, a capacitor that holds the gate voltage of the transistor that controls the light emission brightness, and a transistor for connecting to GND without going through the light-emitting element.

[0161] The light-emitting device has a display area and a peripheral area arranged around the display area. The display area has a pixel circuit, and the peripheral area has a display control circuit. The mobility of the transistors constituting the pixel circuit may be smaller than the mobility of the transistors constituting the display control circuit.

[0162] The slope of the current-voltage characteristics of the transistors constituting the pixel circuit can be smaller than the slope of the current-voltage characteristics of the transistors constituting the display control circuit. The slope of the current-voltage characteristics can be measured using the so-called Vg-Ig characteristic.

[0163] The transistors that make up the pixel circuit are transistors connected to light-emitting elements, such as the first light-emitting element.

[0164] [Pixels] The organic light-emitting device has multiple pixels. Each pixel has subpixels that emit light of a different color from the others. The subpixels may each have, for example, RGB light-emitting colors.

[0165] A pixel emits light in a region also called the pixel aperture. This region is the same as the first region. The pixel aperture may be 15 μm or less, or 5 μm or more. More specifically, it may be 11 μm, 9.5 μm, 7.4 μm, 6.4 μm, etc.

[0166] The distance between subpixels may be 10 μm or less, specifically 8 μm, 7.4 μm, or 6.4 μm.

[0167] Pixels can take on known arrangements in a plan view. For example, they may be in a stripe arrangement, delta arrangement, pentile arrangement, or Bayer arrangement. The shape of subpixels in a plan view may be any known shape. For example, rectangles, rhombuses, hexagons, etc. Of course, even if it is not a precise shape, if it is close to a rectangle, it is included in the category of rectangles. The shape of subpixels and the pixel arrangement can be used in combination.

[0168] <Applications of the organic light-emitting element according to one embodiment of the present invention> An organic light-emitting element according to one embodiment of the present invention can be used as a component of a display device or lighting device. Other applications include exposure light sources for electrophotographic image forming apparatuses, backlights for liquid crystal display devices, and light-emitting devices with a color filter in a white light source.

[0169] The display device may also be an image information processing device that has an image input unit for receiving image information from an area CCD, linear CCD, memory card, etc., an information processing unit for processing the input information, and displays the input image on the display unit.

[0170] Furthermore, the display unit of the imaging device or inkjet printer may have a touch panel function. The driving method for this touch panel function may be infrared, capacitive, resistive, or electromagnetic induction, and is not particularly limited. The display device may also be used as the display unit of a multifunction printer.

[0171] Next, the display device according to this embodiment will be described with reference to the drawings.

[0172] Figure 1 is a schematic cross-sectional view showing an example of a display device having an organic light-emitting element and a transistor connected to this organic light-emitting element. The transistor is an example of an active element. The transistor may also be a thin-film transistor (TFT).

[0173] Figure 1(a) shows an example of a pixel, which is a component of the display device according to this embodiment. The pixel has sub-pixels 10. The sub-pixels are divided into 10R, 10G, and 10B based on their light emission. The light emission color may be distinguished by the wavelength emitted from the light-emitting layer, or the light emitted from the sub-pixel may be selectively transmitted or color-converted by a color filter or the like. Each sub-pixel has a reflective electrode 2 which is a first electrode, an insulating layer 3 covering the end 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 on an interlayer insulating layer 1.

[0174] The interlayer insulating layer 1 may have transistors and capacitive elements placed in the layer below or inside it. The transistor and the first electrode may be electrically connected via a contact hole or the like (not shown).

[0175] The insulating layer 3 is also called the bank or pixel isolation layer. It covers the edge of the first electrode and surrounds the first electrode. The portion without the insulating layer is in contact with the organic compound layer 4 and becomes the light-emitting region.

[0176] 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.

[0177] The second electrode 5 may be a transparent electrode, a reflective electrode, or a semi-transparent electrode.

[0178] The protective layer 6 reduces the penetration of moisture into the organic compound layer. Although the protective layer is shown as a single layer, it may consist of multiple layers. Each layer may contain an inorganic compound layer and an organic compound layer.

[0179] The color filters 7 are classified into 7R, 7G, and 7B according to their color. The color filters may be formed on a planarization film (not shown). The color filters may also have a resin protective layer (not shown). Alternatively, the color filters may be formed on a protective layer 6, or they may be bonded together after being placed on an opposing substrate such as a glass substrate.

[0180] The display device 100 in Figure 1(b) shows an organic light-emitting element 26 and a TFT 18 as an example of a transistor. A substrate 11 made of glass, silicon, or the like is provided, with an insulating layer 12 on top of it. An active element 18 such as a TFT is placed on the insulating layer, and the gate electrode 13, gate insulating film 14, and semiconductor layer 15 of the active element are arranged therein. The TFT 18 is also composed of a semiconductor layer 15, a drain electrode 16, and a source electrode 17. An insulating film 19 is provided on top of the TFT 18. The anode 21 and the source electrode 17 that constitute the organic light-emitting element 26 are connected via a contact hole 20 provided in the insulating film.

[0181] Note that the method of electrical connection between the electrodes (anode, cathode) included in the organic light-emitting element 26 and the electrodes (source electrode, drain electrode) included in the TFT is not limited to the configuration shown in Figure 1(b). In other words, it is sufficient if either the anode or cathode is electrically connected to either the source electrode or the drain electrode of the TFT. TFT refers to a thin-film transistor.

[0182] In the display device 100 shown in Figure 1(b), the organic compound layer is depicted as a single layer, but the organic compound layer 22 may consist of multiple layers. A first protective layer 24 and a second protective layer 25 are provided on the cathode 23 to reduce the degradation of the organic light-emitting element.

[0183] In the display device 100 shown in Figure 1(b), a transistor is used as the switching element, but other switching elements may be used instead.

[0184] Furthermore, the transistor used in the display device 100 in Figure 1(b) is not limited to a transistor using a single-crystal silicon wafer, but may also be a thin-film transistor having an active layer on an insulating surface of the substrate. Examples of active layers include non-single-crystal silicon such as single-crystal silicon, 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 called TFT elements.

[0185] The transistors included in the display device 100 in Figure 1(b) may be formed within a substrate such as a Si substrate. Here, "formed within a substrate" means that the transistors are manufactured by processing the substrate itself, such as a Si substrate. In other words, having transistors within a substrate can be seen as the substrate and transistors being formed as a single unit.

[0186] The organic light-emitting element according to this embodiment has its luminescence controlled by a TFT, which is an example of a switching element, and by providing multiple organic light-emitting elements on the surface, an image can be displayed using the luminescence of each element. The switching element according to this embodiment is not limited to a TFT, but may also be a transistor made of low-temperature polysilicon, or an active matrix driver formed on a substrate such as a Si substrate. "On the substrate" can also mean "within the substrate." Whether to provide a transistor within the substrate or to use a TFT is selected depending on the size of the display area; for example, if the size is about 0.5 inches, it is preferable to provide the organic light-emitting element on a Si substrate.

[0187] Figure 2 is a schematic diagram showing an example of a display device according to this embodiment. The display device 1000 may have a touch panel 1003, a display panel 1005, a frame 1006, a circuit board 1007, and a battery 1008 between an upper cover 1001 and a lower cover 1009. Flexible printed circuits FPCs 1002 and 1004 are connected to the touch panel 1003 and the display panel 1005. Transistors are printed on the circuit board 1007. The battery 1008 does not need to be provided if the display device is not a portable device, or it may be provided in a different location even if it is a portable device.

[0188] The display device according to this embodiment may have a color filter having red, green, and blue colors. The color filter may have the red, green, and blue colors arranged in a delta array.

[0189] The display device according to this embodiment may be used in the display unit of a mobile terminal. In that case, it may have both display and operation functions. Examples of mobile terminals include smartphones and other mobile phones, tablets, and head-mounted displays.

[0190] The display device according to this embodiment may be used in the display unit of an imaging device having an optical unit with multiple lenses and an image sensor that receives light that has passed through the optical unit. The imaging device may have a display unit that displays information acquired by the image sensor. Furthermore, the display unit may be a display unit exposed to the outside of the imaging device or a display unit located inside the viewfinder. The imaging device may be a digital camera or a digital video camera.

[0191] Figure 3(a) is a schematic diagram showing an example of an imaging device according to this embodiment. The imaging device 1100 may include a viewfinder 1101, a rear display 1102, an operation unit 1103, and a housing 1104. The viewfinder 1101 may have a display device according to this embodiment. In that case, the display device may display not only the image to be captured, but also environmental information, imaging instructions, etc. Environmental information may include the intensity of ambient light, the direction of ambient light, the speed at which the subject is moving, the possibility of the subject being obscured by an obstacle, etc.

[0192] Since the optimal timing for imaging is very short, it is best to display the information as quickly as possible. Therefore, it is preferable to use a display device using the organic light-emitting element of the present invention, because organic light-emitting elements have a fast response speed. Display devices using organic light-emitting elements can be used more suitably than liquid crystal display devices, which require a fast display speed.

[0193] The imaging device 1100 has an optical section (not shown). The optical section has multiple lenses that form an image on the image sensor housed in the housing 1104. The focus can be adjusted by adjusting the relative positions of the multiple lenses. This operation can also be performed automatically. The imaging device may also be called a photoelectric converter. The photoelectric converter may not capture images sequentially, but may include imaging methods such as detecting the difference from the previous image or extracting from an image that is always being recorded.

[0194] Figure 3(b) is a schematic diagram showing an example of an electronic device according to this embodiment. The electronic device 1200 has a display unit 1201, an operation unit 1202, and a housing 1203. The housing 1203 may have a circuit, a printed circuit board having the circuit, a battery, and a communication unit. The operation unit 1202 may be a button or a touch panel type response unit. The operation unit may also be a biometric recognition unit that recognizes fingerprints to unlock or otherwise perform actions. An electronic device having a communication unit can also be called a communication device. The electronic device may further have a camera function by including a lens and an image sensor. Images captured by the camera function are displayed on the display unit. Examples of electronic devices include smartphones and laptop computers.

[0195] Figure 4 is a schematic diagram showing an example of a display device according to this embodiment. Figure 4(a) is a display device such as a television monitor or a PC monitor. The display device 1300 has a frame 1301 and a display unit 1302. The display unit 1302 may use the light-emitting device according to this embodiment.

[0196] It has a frame 1301 and a base 1303 that supports the display unit 1302. The base 1303 is not limited to the form shown in Figure 4(a). The bottom edge of the frame 1301 may also serve as the base.

[0197] Furthermore, the frame 1301 and the display section 1302 may be curved. Their radius of curvature may be between 5000 mm and 6000 mm.

[0198] Figure 4(b) is a schematic diagram showing another example of the display device according to this embodiment. The display device 1310 in Figure 4(b) is configured to be foldable and is a so-called foldable display device. The display device 1310 has a first display unit 1311, a second display unit 1312, a housing 1313, and a bending point 1314. The first display unit 1311 and the second display unit 1312 may have light-emitting devices according to this embodiment. The first display unit 1311 and the second display unit 1312 may be a single display device without seams. The first display unit 1311 and the second display unit 1312 can be separated at a bending point. The first display unit 1311 and the second display unit 1312 may each display different images, or the first and second display units may together display a single image.

[0199] Figure 5(a) is a schematic diagram showing an example of a lighting device according to this embodiment. The lighting device 1400 may include a housing 1401, a light source 1402, a circuit board 1403, an optical film 1404, and a light diffusion section 1405. The light source may have an organic light-emitting element according to this embodiment. The optical filter may be a filter that improves the color rendering of the light source. The light diffusion section can effectively diffuse the light from the light source, such as for lighting up, and deliver light over a wide area. The optical filter and light diffusion section may be provided on the light-emitting side of the lighting. A cover may be provided on the outermost part as needed.

[0200] The lighting device is, for example, a device for illuminating a room. The lighting device may emit white light, cool white light, or any other color from blue to red. It may have a dimming circuit to adjust the brightness of these lights. The lighting device may have the organic light-emitting element of the present invention and a power supply circuit connected thereto. The power supply circuit is a circuit that converts AC voltage to DC voltage. White light has a color temperature of 4200K, and cool white light has a color temperature of 5000K. The lighting device may have a color filter.

[0201] Furthermore, the lighting device according to this embodiment may have a heat dissipation section. The heat dissipation section releases heat from inside the device to the outside, and examples include metals with high specific heat, liquid silicon, etc.

[0202] Figure 5(b) is a schematic diagram of an automobile, which is an example of a mobile body according to this embodiment. The automobile has a taillight, which is an example of a lighting device. The automobile 1500 has a taillight 1501, and may be configured to illuminate when the brakes are applied or the like.

[0203] The tail lamp 1501 may have an organic light-emitting element according to this embodiment. The tail lamp may have a protective member to protect the organic EL element. The protective member has a reasonably high strength and can be made of any transparent material, but it is preferably made of polycarbonate or the like. A frangic acid derivative, an acrylonitrile derivative, or the like may be mixed with the polycarbonate.

[0204] The automobile 1500 may have a body 1503 and windows 1502 attached thereto. The windows may be transparent displays, unless they are windows for checking the front and rear of the automobile. The transparent displays may have organic light-emitting elements according to this embodiment. In this case, the constituent materials such as electrodes of the organic light-emitting element are made of transparent members.

[0205] The mobile body according to this embodiment may be a ship, aircraft, drone, etc. The mobile body may have a body and a lighting device provided on the body. The lighting device may emit light to indicate the position of the body. The lighting device has an organic light-emitting element according to this embodiment.

[0206] Referencing Figure 6, examples of applications of the display devices of each embodiment described above will be explained. The display device can be applied to systems that can be worn as wearable devices such as smart glasses, HMDs, and smart contact lenses. The imaging display device used in such applications comprises an imaging device capable of photoelectric conversion of visible light and a display device capable of emitting visible light.

[0207] Figure 6(a) illustrates a pair of glasses 1600 (smart glasses) according to one application example. An imaging device 1602, such as a CMOS sensor or SPAD, is provided on the front surface of the lens 1601 of the glasses 1600. In addition, the display devices of each embodiment described above are provided on the back surface of the lens 1601.

[0208] The eyeglasses 1600 further include a control device 1603. The control device 1603 functions as a power supply that provides power to the imaging device 1602 and the display device according to each embodiment. The control device 1603 also controls the operation of the imaging device 1602 and the display device. The lens 1601 has an optical system formed therein for focusing light onto the imaging device 1602.

[0209] Figure 6(b) illustrates a pair of glasses 1610 (smart glasses) according to one application example. The glasses 1610 have a control device 1612, which is equipped with an imaging device equivalent to an imaging device 1602 and a display device. The lens 1611 has an optical system formed therein for projecting light emitted from the imaging device and the display device within the control device 1612, and an image is projected onto the lens 1611. The control device 1612 functions as a power supply to provide power to the imaging device and the display device, and also controls the operation of the imaging device and the display device. The control device may have a gaze detection unit that detects the wearer's gaze. Gaze detection may use infrared light. The infrared light emitter emits infrared light towards the eyeball of the user who is fixating on the displayed image. The imaging unit, which has a photodetector, detects the reflected light from the eyeball of the emitted infrared light, thereby obtaining an image of the eyeball. By having a reduction means that reduces the light from the infrared light emitter to the display unit in planar view, the degradation of image quality is reduced.

[0210] The user's gaze towards the displayed image is detected from an image of the eyeball obtained by imaging with infrared light. Any known method can be applied to gaze detection using an image of the eyeball. For example, a gaze detection method based on the Purkinje image obtained by the reflection of the irradiated light from the cornea can be used.

[0211] More specifically, gaze detection processing is performed based on the pupil-corneal reflection method. Using the pupil-corneal reflection method, a gaze vector representing the orientation (rotation angle) of the eyeball is calculated based on the pupil image and Purkinje image contained in the captured image of the eyeball, thereby detecting the user's gaze.

[0212] A display device according to one embodiment of the present invention includes an imaging device having a light-receiving element, and may control the display image of the display device based on the user's gaze information from the imaging device.

[0213] Specifically, the display device determines a first field of view that the user is fixated on, and a second field of view other than the first field of view, based on gaze information. The first and second field of view may be determined by the control device of the display device, or they may be determined by an external control device and received by the display device. Within the display area of ​​the display device, the display resolution of the first field of view may be controlled to be higher than the display resolution of the second field of view. In other words, the resolution of the second field of view may be lower than that of the first field of view.

[0214] Furthermore, the display area has a first display area and a second display area different from the first display area, and based on gaze information, the area with higher priority is determined from the first display area and the second display area. The first and second view areas may be determined by the control device of the display device, or they may be determined by an external control device and received. The resolution of the high-priority area may be controlled to be higher than the resolution of the areas other than the high-priority area. In other words, the resolution of areas with relatively lower priority may be set lower.

[0215] AI may be used to determine the primary field of view and high-priority areas. The AI ​​may be a model configured to estimate the angle of gaze and the distance to the target object at the end of the line of sight from the image of the eye, using the image of the eye and the direction the eye was actually looking in that image as training data. The AI ​​program may be installed in the display device, the imaging device, or an external device. If installed in an external device, it will be transmitted to the display device via communication.

[0216] When display control is based on visual detection, this method is preferably applicable to smart glasses that further include an imaging device for capturing images of the surrounding environment. The smart glasses can display the captured external information in real time.

[0217] Figure 7(a) is a schematic diagram showing an example of an image forming apparatus according to one embodiment of the present invention. The image forming apparatus 40 is an electrophotographic image forming apparatus and includes a photoreceptor 27, an exposure light source 28, a charging unit 30, a developing unit 31, a transfer unit 32, a transport roller 33, and a fuser 35. Light 29 is irradiated from the exposure light source 28, and an electrostatic latent image is formed on the surface of the photoreceptor 27. This exposure light source 28 has an organic light-emitting element according to this embodiment. The developing unit 31 has toner or the like. The charging unit 30 charges the photoreceptor 27. The transfer unit 32 transfers the developed image to a storage medium 34. The transport roller 33 transports the recording medium 34. The recording medium 34 is, for example, paper. The fuser 35 fixes the image formed on the recording medium 34.

[0218] Figures 7(b) and 7(c) are diagrams showing the exposure light source 28, and are schematic diagrams showing how multiple light-emitting units 36 are arranged on a long substrate. Arrows 37 indicate the direction of the column in which the organic light-emitting elements are arranged. This column direction is the same as the direction of the axis in which the photoreceptor 27 rotates. This direction can also be called the long axis direction of the photoreceptor 27. Figure 7(b) shows a configuration in which the light-emitting units 36 are arranged along the long axis direction of the photoreceptor 27. Figure 7(c) is a different configuration from Figure 7(b), in which the light-emitting units 36 are arranged alternately in the column direction in the first column and the second column. The first column and the second column are arranged at different positions in the row direction. In the first column, multiple light-emitting units 36 are arranged with intervals between them. In the second column, light-emitting units 36 are located at positions corresponding to the intervals between the light-emitting units 36 in the first column. That is, multiple light-emitting units 36 are also arranged with intervals between them in the row direction. The arrangement in Figure 7(c) can also be described as a grid pattern, a houndstooth pattern, or a checkerboard pattern.

[0219] As described above, by using the device using the organic light-emitting element according to the present embodiment, it is possible to achieve a good image quality and a stable display even for a long-time display.

Example

[0220] Hereinafter, the present invention will be described by way of examples. However, the present invention is not limited thereto.

[0221] [Example 1 (Synthesis of Exemplary Compound C-1)] Exemplary compound C-1 was synthesized according to the following scheme.

[0222]

Chemical formula

[0223] (1) Synthesis of Compound f-3 The following reagents and solvents were charged into a 200 ml eggplant flask. Compound f-1: 6.46 g (20.0 mmol) Compound f-2: 2.27 g (20.0 mmol) Sodium carbonate: 5.3 g (50.0 mmol) Pd(PPh3)4: 578 mg Toluene: 90 ml Water: 35 ml Ethanol: 10 ml

[0224] Next, the reaction solution was heated under reflux with stirring for 10 hours under a nitrogen stream. After completion of the reaction, extraction was performed with toluene, and the organic layer was concentrated to dryness. The obtained solid was purified by silica gel column chromatography (toluene: ethyl acetate mixture) to obtain 0.77 g (yield: 12%) of a transparent solid (f-3).

[0225] (2) Synthesis of Compound f-4 The following reagents and solvents were charged into a 50 ml eggplant flask. Compound f-3: 3.21 g (10.0 mmol) Iridium chloride hydrate: 0.80 g Ethoxyethanol: 15ml Water: 5ml

[0226] Next, the reaction solution was heated and stirred at 130°C under a nitrogen stream for 5 hours. After the reaction was complete, the reaction solution was filtered, and the resulting solid was washed with water and methanol on the filter. A yellow solid (f-4) of 1.9 g was obtained.

[0227] (3) Compound f-5 synthesis The following reagents and solvents were placed in a 100 ml round-bottom flask. Compound f-5:1.74(1.00mmol) Silver triflate: 0.514g (2.00 mmol) Methylene chloride: 30 ml Methanol: 1.3 ml

[0228] Next, the reaction solution was heated and stirred at room temperature under a nitrogen stream for 6 hours. After the reaction was complete, the solvent was removed from the reaction solution at 40°C. 1.85 g of a yellowish-brown solid (f-5) was obtained.

[0229] (4) Synthesis of Exemplary Compound C-1 The following reagents and solvents were placed in a 100 ml round-bottom flask. Compound f-5: 1.20g Compound f-3: 0.16g (1.00mmol) Ethanol: 60ml

[0230] Next, the reaction solution was heated and stirred at 90°C under a nitrogen stream for 5 hours. After the reaction was complete, the reaction solution was filtered, and the resulting solid was washed with water and methanol on the filter. The resulting solid was purified by silica gel column chromatography (toluene:ethyl acetate mixture) to obtain 0.28 g of a yellow solid (exemplary compound C-1) (yield: 28%).

[0231] For example compound F-1, mass spectrometry was performed using MALDI-TOF-MS (Bruker Autoflex LRF).

[0232] [MALDI-TOF-MS] Measured value: m / z = 987 Calculated value: C 59 H 44 IrN3 = 987

[0233] [Examples 2 to 21 (Synthesis of Exemplary Compounds)] In Tables 3-1 to 3-3, for the exemplary compounds shown in Examples 2 to 21, the exemplary compounds were synthesized in the same manner as in Example 1, except that starting material f-1 in Example 1 was changed to starting material 1, starting material f-2 was changed to starting material 2, and starting material f-6 was changed to starting material 3. Also, the measured value of m / z in the mass spectrometry results measured in the same manner as in Example 1 is shown.

[0234]

Table 3-1

[0235]

Table 3-2

[0236] [[ID=​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​

[0240] Next, the reaction solution was heated and stirred at 100°C under a nitrogen stream for 5 hours. After cooling, methanol was added, filtered, and washed with methanol. 0.33 g of yellow solid (C-35) was obtained (yield: 35%).

[0241] For example compound D-16, mass spectrometry was performed using MALDI-TOF-MS (Bruker Autoflex LRF).

[0242] [MALDI-TOF-MS] Measured value: m / z = 933 Calculated value: C 53 H 46 IrO2N3 = 933

[0243] [Examples 23 to 28 (Synthesis of Exemplary Compounds)] Table 2 shows the example compounds shown in Examples 23 to 28, synthesized in the same manner as in Example 22, except that raw material f-3 was replaced with raw material 1 and raw material f-8 with raw material 2. The measured values ​​(m / z) of the mass spectrometry results, measured in the same manner as in Example 22, are also shown.

[0244] [Table 4]

[0245] [Example 29 (Synthesis of Exemplary Compound C-31)] Exemplary compound C-31 was synthesized according to the following scheme.

[0246] [ka]

[0247] (1) Synthesis of Exemplary Compound C-31 The following reagents and solvents were placed in a 100 ml round-bottom flask. Compound C-35: 0.93g (1.00mmol) Compound f-3: 0.80g (2.50mmol) Sodium carbonate: 1.06g (10.0 mmol) Glycerol: 40ml

[0248] Next, after degassing with nitrogen, the reaction solution was heated and stirred at 180°C for 7 hours. After cooling, methanol was added, filtered, and washed with methanol. The resulting solid was purified by silica gel column chromatography (toluene:ethyl acetate mixture) to obtain 0.15 g of a yellow solid (exemplary compound J-1) (yield: 13%).

[0249] For example compound C-31, mass spectrometry was performed using MALDI-TOF-MS (Bruker Autoflex LRF).

[0250] [MALDI-TOF-MS] Measured value: m / z = 1153 Calculated value: C 72 H 54 IrN3=1153

[0251] [Examples 30 to 32 (Synthesis of Exemplary Compounds)] Table 5 shows the example compounds shown in Examples 30 to 32, synthesized in the same manner as in Example 29, except that raw material C-35 was replaced with raw material 1 and raw material f-3 with raw material 2. The measured values ​​(m / z) of the mass spectrometry results, measured in the same manner as in Example 29, are also shown.

[0252] [Table 5]

[0253] [Example 33] An organic light-emitting device with a bottom-emission structure was fabricated on a substrate, in which an anode, hole injection layer, hole transport layer, electron blocking layer, light-emitting layer, hole blocking layer, electron transport layer, electron injection layer, and cathode were sequentially formed.

[0254] First, an ITO film was deposited on a glass substrate, and an ITO electrode (anode) was formed by applying the desired patterning process. At this time, the film thickness of the ITO electrode was set to 100 nm. The substrate on which the ITO electrode was formed in this way was used as the ITO substrate in the following process. Next, 1.3 × 10 -4 Vacuum deposition was performed by resistance heating in a Pa vacuum chamber to continuously deposit the organic compound layer and electrode layer shown in Table 6 onto the ITO substrate. At this time, the electrode area of ​​the opposing electrodes (metal electrode layer, cathode) was 3 mm². 2 I made it so that it would be like that.

[0255] [Table 6]

[0256] The characteristics of the obtained elements were measured and evaluated. The efficiency of the light-emitting element was 68 cd / A.

[0257] Furthermore, the current density is 50 mA / cm². 2 A continuous operation test was conducted, and the time at which the brightness degradation rate reached 5% was measured. This time was set to 1.0 in this embodiment.

[0258] In this embodiment, the measuring device specifically measured the current-voltage characteristics with a Hewlett-Packard 4140B micro-ammeter, and the luminous intensity with a Topcon BM7.

[0259] [Examples 34 to 38, Comparative Examples 1 to 3] In Examples 34 to 38 and Comparative Examples 1 to 3, organic light-emitting devices were fabricated in the same manner as in Example 33, except that the materials of the light-emitting layer shown in Table 7 were appropriately changed. The obtained devices were evaluated in the same manner as in Example 33. Furthermore, the current density was 50 mA / cm². 2 A continuous operation test was conducted, and the time at which the brightness degradation rate reached 5% was measured. The ratio of the brightness degradation time in this example to the time at which the brightness degradation rate reached 5% in Example 33 is set to 1.0 is shown.

[0260] The measurement results are shown in Table 7. Compounds Q-2-1 and A-1 are the following compounds.

[0261] [ka]

[0262] [Table 7]

[0263] Table 7 shows that the light-emitting element according to the present invention exhibits high-efficiency emission and minimal brightness degradation. The dopant material of the light-emitting element in Comparative Example 1 is an organometallic complex having an azafluorene ring, resulting in low luminescence efficiency and significant brightness degradation. Furthermore, the host materials of the light-emitting elements in Comparative Examples 2 and 3 contain highly polar atoms other than hydrocarbons, such as nitrogen atoms, resulting in weak interaction with the iridium complex of the present invention, low luminescence efficiency, and poor stability of the host material, leading to significant brightness degradation.

[0264] Based on the above, by using the compounds of general formulas (1) to (3) according to the present invention as luminescent dopants and selecting a preferred host material, it is possible to provide a device with high efficiency and excellent durability.

[0265] [Example 39] An organic light-emitting device with a bottom-emission structure was fabricated on a substrate, in which an anode, hole injection layer, hole transport layer, electron blocking layer, light-emitting layer, hole blocking layer, electron transport layer, electron injection layer, and cathode were sequentially formed.

[0266] First, an ITO film was deposited on a glass substrate, and an ITO electrode (anode) was formed by applying the desired patterning process. At this time, the film thickness of the ITO electrode was set to 100 nm. The substrate on which the ITO electrode was formed in this way was used as the ITO substrate in the following process. Next, 1.3 × 10 -4Vacuum deposition was performed by resistance heating in a Pa vacuum chamber to continuously deposit the organic compound layer and electrode layer shown in Table 8 onto the ITO substrate. At this time, the electrode area of ​​the opposing electrodes (metal electrode layer, cathode) was 3 mm². 2 I made it so that it would be like that.

[0267] [Table 8]

[0268] The characteristics of the obtained elements were measured and evaluated. The efficiency of the light-emitting element was 66 cd / A.

[0269] Furthermore, the current density is 50 mA / cm². 2 A continuous operation test was conducted, and the time at which the brightness degradation rate reached 5% was measured. This time was set to 1.0 in this embodiment.

[0270] In this embodiment, the measuring device specifically measured the current-voltage characteristics with a Hewlett-Packard 4140B micro-ammeter, and the luminous intensity with a Topcon BM7.

[0271] [Examples 40 to 44, Comparative Examples 4 to 6] In Examples 40 to 44, organic light-emitting devices were fabricated in the same manner as in Example 39, except that the dopant materials shown in Table 12 were appropriately changed. The obtained devices were evaluated in the same manner as in Example 39. Furthermore, the current density was 50 mA / cm². 2 A continuous operation test was conducted, and the time at which the brightness degradation rate reached 5% was measured. The ratio of the brightness degradation time in this example to the time at which the brightness degradation rate reached 5% in Example 39 is set to 1.0 is shown.

[0272] The measurement results are shown in Table 9.

[0273] [Table 9]

[0274] Table 9 shows that the light-emitting element according to the present invention exhibits high-efficiency light emission and minimal brightness degradation. Comparative Examples 4 to 6 have host materials that contain highly polar atoms other than hydrocarbons, such as nitrogen atoms and sulfur atoms. As a result, the interaction with the iridium complex of the present invention is weak, leading to low luminescence efficiency and poor stability of the host material, resulting in significant brightness degradation.

[0275] Based on the above, by using compounds of general formulas (1) to (3) according to the present invention as dopant materials and selecting preferred host materials and assist materials, it is possible to provide a device with high efficiency and excellent durability. [Explanation of symbols]

[0276] Single interlayer insulating layer 2 reflective electrode 3. Insulating layer 4 Organic compound layer 5 Transparent electrode 6 Protective layer 7 Color Filters 10 subpixels 11 circuit boards 12 Insulating layer 13 gates 14 Gate insulating film 15 Semiconductor layer 16 Drain electrode 17 Source electrodes 18 Thin-film transistors 19 Insulating film 20 contact holes 21 Lower electrode 22 Organic compound layer 23 Upper electrode 24 First protective layer 25 Second protective layer 26 Organic light-emitting diodes 100 display device 1000 display devices 1001 Top cover 1002 Flexible Printed Circuits 1003 Touch Panel 1004 Flexible Printed Circuit 1005 Display Panel 1006 Frame 1007 Circuit board 1008 Battery 1009 Lower cover 1100 Imaging device 1101 Viewfinder 1102 Rear display 1103 Operation section 1104 cabinet 1200 Electronic equipment 1201 Display section 1202 Operation unit 1203 enclosure 1300 display device 1301 Picture frame 1302 Display section 1303 Base 1310 Display device 1311 First display section 1312 Second display section 1313 cabinet 1314 Inflection point 1400 Lighting devices 1401 cabinet 1402 Light source 1403 Circuit board 1404 Optical Film 1405 Light Diffusion Section 1500 cars 1501 Taillight 1502 Window 1503 Body 1600 Smart Glasses 1601 Lens 1602 Imaging device 1603 Control device 1610 Smart Glasses 1611 Lens 1612 Control device

Claims

1. An organometallic complex characterized by being represented by general formulas (1) to (3). 【Chemistry 1】 (In general formulas (1) to (3), R １ and R ２ The methyl group and CD ３ Each element is independently selected from the group consisting of elements. R ３ This represents a substituent that substitutes for the phenyl group, and is independently selected from the group consisting of a deuterium atom, an unsubstituted alkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 4 carbon atoms with a deuterium atom or a fluorine atom as a substituent, and an aryl group having 6 to 13 carbon atoms. R ４ ~R ６ This represents a substituent that substitutes for the ring structure constituting azabenzofluorene, and is independently selected from the group consisting of a deuterium atom, a fluorine atom, a bromine atom, an unsubstituted alkyl group having 1 to 4 carbon atoms, and an alkyl group having 1 to 4 carbon atoms with a deuterium atom or a fluorine atom as a substituent. m represents an integer from 1 to 3, and n represents an integer from 0 to 2, where m + n is 3. X represents a bidental ligand, and the substructure Ir(X)n is one of the structures shown in general formulas (4) or (5) below. The three ligands may be the same or different. p is an integer between 0 and 2 (inclusive). 【Chemistry 2】 (In general formula (4) or (5), R ９ to R １９ are each independently selected from the group consisting of a hydrogen atom, a deuterium atom, an unsubstituted alkyl group having 1 to 4 carbon atoms, an alkyl group having 1 to 4 carbon atoms having a deuterium atom or a fluorine atom as a substituent, and a phenyl group. Further, R １６ to R １９ may form a ring with each other.) Multiple R3s may bond to each other to form a ring structure of any of the general formulas (10) to (15) or (18) to (20). 【Transformation 3】 (In general formulas (10) to (15), (18) to (20), R ７ is a deuterium atom, an unsubstituted alkyl group having 1 to 4 carbon atoms, or an alkyl group having 1 to 4 carbon atoms with a deuterium atom or a fluorine atom as a substituent. Y is C(R ２０ ) (Caution ２１ ) and R ２０ and R ２１ (This is a methyl group. * indicates the bond position to the azabenzofluorene ring.)

2. In general formulas (1) to (3), multiple R ３ The organometallic complex according to claim 1, characterized in that the ring structure formed is represented by any one of the general formulas (11), (12), (14), (15), (19), and (20).

3. In general formulas (1) to (3), R ３ or R ４ The organometallic complex according to claim 1, characterized in that at least one of them is a substituent.

4. In general formulas (1) to (3), R ３ or R ４ The organometallic complex according to claim 1, characterized in that at least one of them is a tert-butyl group.

5. The first electrode and the second electrode, An organic light-emitting element having an organic compound layer disposed between the first electrode and the second electrode, The organic light-emitting element is characterized in that the organic compound layer contains an organometallic complex according to any one of claims 1 to 4.

6. The aforementioned organic compound layer has a light-emitting layer, The organic light-emitting element according to claim 5, characterized in that the light-emitting layer has the organometallic complex.

7. The light-emitting layer further comprises the first compound, The organic light-emitting element according to claim 6, characterized in that the first compound is a compound with a lower minimum excitation triplet energy greater than that of the organometallic complex.

8. The organic light-emitting element according to claim 7, characterized in that the first compound is a hydrocarbon compound.

9. The organic light-emitting element according to claim 7 or 8, characterized in that the first compound has at least one skeleton of triphenylene, naphthalene, phenanthrene, chrysene, or fluorantene.

10. The organic light-emitting element according to any one of claims 7 to 9, characterized in that the first compound does not contain SP3 carbon.

11. The light-emitting layer further comprises a second compound, The organic light-emitting element according to any one of claims 7 to 10, characterized in that the lowest excited triplet energy of the second compound is equal to or greater than the lowest excited triplet energy of the organometallic complex.

12. The organic light-emitting device according to claim 11, characterized in that the second compound has an electron-withdrawing group.

13. The organic light-emitting element according to claim 12, characterized in that the second compound has at least one of the following structures. 【Chemistry 4】 (X represents oxygen, sulfur, or a substituted or unsubstituted carbon atom.)

14. The organic light-emitting element according to claim 13, characterized in that the second compound is any of the following compounds. 【Transformation 5】

15. A display device having a plurality of pixels, wherein at least one of the plurality of pixels is an organic light-emitting element according to any one of claims 5 to 14 and a transistor connected to the organic light-emitting element.

16. It comprises an optical unit having multiple lenses, an image sensor that receives light that has passed through the optical unit, and a display unit that displays the image captured by the image sensor. The photoelectric conversion device is characterized in that the display unit has an organic light-emitting element as described in any one of claims 5 to 14.

17. An electronic device comprising: a display unit having an organic light-emitting element as described in any one of claims 5 to 14; a housing on which the display unit is provided; and a communication unit provided in the housing for communicating with the outside.

18. A lighting device comprising a light source having an organic light-emitting element according to any one of claims 5 to 14, and a light-diffusing portion or optical film that transmits light emitted by the light source.

19. A mobile body characterized by comprising a lamp having an organic light-emitting element as described in any one of claims 5 to 14, and a body on which the lamp is provided.

20. It comprises a photoreceptor and an exposure light source for exposing the photoreceptor, The image forming apparatus is characterized in that the exposure light source has an organic light-emitting element as described in any one of claims 5 to 14.

Images