Organic compounds and organic light-emitting elements

Abstract

To provide an organic compound excellent in light emission efficiency and durability characteristics.SOLUTION: The organic compound is represented by general formula [1] in the figure. In the formula, R1 to R10 are each independently selected from the group consisting of a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group. However, at least one of R2, R3, R8 and R9 is selected from the group consisting of a deuterium atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group.SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to an organic compound and an organic light-emitting device.

Background Art

[0002] An organic light-emitting device (hereinafter sometimes referred to as an "organic electroluminescence device" or an "organic EL device") is an electronic device having a pair of electrodes and an organic compound layer disposed between these electrodes. By injecting electrons and holes from these pair of electrodes, excitons of a light-emitting organic compound in the organic compound layer are generated, and when the excitons return to the ground state, the organic light-emitting device emits light. The recent progress of organic light-emitting devices is remarkable, and examples include low driving voltage, various emission wavelengths, high-speed responsiveness, and the ability to make the light-emitting device thinner and lighter. By the way, the creation of compounds suitable for organic light-emitting devices has been actively carried out until now. This is because in providing a high-performance organic light-emitting device, the creation of a compound with excellent element lifetime characteristics is important. As a compound created so far, chromeno[2,3-a]xanthene-8,14-dione (CXD) is described in Patent Document 1.

[0003]

Chemical Formula

[0006] The organic compound of the present invention is characterized by being represented by the following general formula [1].

[0007] [ka] In the general formula [1], R1 to R 10 Each of the following is independently selected from a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group. However, at least one of R2, R3, R8, and R9 is selected from a deuterium atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group. [Effects of the Invention]

[0008] According to the present invention, it is possible to provide an organic compound with excellent luminescence efficiency and durability. Furthermore, by using the organic compound of the present invention as a host molecule for a light-emitting layer, it is possible to provide an organic light-emitting element with excellent luminescence efficiency and durability. [Brief explanation of the drawing]

[0009] [Figure 1] (a) A schematic cross-sectional view showing an example of a pixel of a display device according to one embodiment of the present invention. (b) A schematic cross-sectional view showing an example of a display device using an organic light-emitting element according to one embodiment of the present invention. [Figure 2] This is a schematic diagram illustrating an example of a display device according to one embodiment of the present invention. [Figure 3] (a) A schematic diagram showing an example of an imaging device according to one embodiment of the present invention. (b) A schematic diagram showing an example of an electronic device according to one embodiment of the present invention. [Figure 4](a) A schematic diagram showing an example of a display device according to an embodiment of the present invention. (b) A schematic diagram showing an example of a foldable display device. [Figure 5] (a) A schematic diagram showing an example of a lighting device according to an embodiment of the present invention. (b) A schematic diagram showing an example of a moving body having a vehicle lamp according to an embodiment of the present invention. [Figure 6] (a) A schematic diagram showing an example of a wearable device according to an embodiment of the present invention. (b) A schematic diagram showing another example of a wearable device according to an embodiment of the present invention. [Figure 7] (a) A schematic diagram showing an example of an image forming apparatus according to an embodiment of the present invention. (b) A schematic diagram showing an example of an exposure light source of an image forming apparatus according to an embodiment of the present invention.

Embodiments for Carrying Out the Invention

[0010] ≪Organic Compound≫ The organic compound of the present embodiment is represented by the following general formula [1].

Chemical Formula

[0011] <R1 to R 10 > In general formula [1], R1 to R 10 are each independently selected from a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group. However, at least one of R2, R3, R8, and R9 is selected from a deuterium atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group.

[0012] At least one or two, preferably two, of R2, R3, R8, and R9 are preferably selected from substituted or unsubstituted alkyl groups, substituted or unsubstituted aryl groups, and substituted or unsubstituted heterocyclic groups, and more preferably selected from substituted or unsubstituted aryl groups and substituted or unsubstituted heterocyclic groups. Furthermore, at least one of R2, R3 and at least one of R8, R9 are preferably selected from substituted or unsubstituted alkyl groups, substituted or unsubstituted aryl groups, and substituted or unsubstituted heterocyclic groups, and more preferably selected from substituted or unsubstituted aryl groups and substituted or unsubstituted heterocyclic groups. Most preferably, R2 and R8 are preferably selected from substituted or unsubstituted alkyl groups, substituted or unsubstituted aryl groups, and substituted or unsubstituted heterocyclic groups, and more preferably selected from substituted or unsubstituted aryl groups and substituted or unsubstituted heterocyclic groups.

[0013] Examples of alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, isobutyl, secondary butyl, octyl, dodecyl, cyclohexyl, 1-adamantyl, and 2-adamantyl groups. Among these, methyl and tert-butyl groups are preferred.

[0014] Examples of aryl groups include, but are not limited to, phenyl, naphthyl, indenyl, biphenyl, terphenyl, fluorenyl, anthracenyl, phenanthryl, fluoranthenyl, pyrenyl, chrysenyl, triphenylenyl, and perilenyl groups. Among these, phenyl, biphenyl, terphenyl, fluorenyl, and phenanthryl groups are preferred.

[0015] Examples of heterocyclic groups include, but are not limited to, pyridyl, pyrimidyl, pyrazyl, triazyl, triazolyl, oxazolyl, oxadiazolyl, thiazolyl, thiadiazolyl, quinolyl, acridinyl, phenantrolyl, dibenzofuranyl, and dibenzothienyl groups. Among these, pyridyl, pyrimidyl, pyrazyl, triazyl, phenantrolyl, dibenzofuranyl, and dibenzothienyl groups are preferred. The heterocyclic group is preferably a heteroaryl group and preferably a group bonded by carbon atoms.

[0016] Examples of substituents that alkyl groups, aryl groups, and heterocyclic groups may further include, but are not limited to, deuterium atoms; alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, secondary butyl, octyl, cyclohexyl, 1-adamantyl, and 2-adamantyl groups; aryl groups such as phenyl, naphthyl, indenyl, biphenyl, terphenyl, fluorenyl, phenanthryl, fluoranthenyl, and triphenylenyl groups; heterocyclic groups such as pyridyl, pyrimidyl, pyrazyl, triazyl, triazyl, oxazolyl, oxadiazolyl, thiazolyl, thiadiazolyl, acridinyl, phenanthryl, dibenzofuranyl, and dibenzothienyl groups; and cyano groups.

[0017] The organic compound of this embodiment has a structure in which specific groups other than hydrogen atoms are introduced at specific positions in the CXD skeleton. This improves chemical stability compared to CXD, enabling superior durability when used as a host molecule in the light-emitting layer of an organic light-emitting device. The mechanism of this effect is described in detail below.

[0018] Hydrocarbon or heterocyclic condensed polycyclic compounds have high electron density on the ring plane and are highly chemically reactive. They are particularly reactive to electrophilic substitution reactions and are known to react with electrophilic species in electron-deficient states. In the light-emitting layer of organic light-emitting devices, host molecules in a radical cation state exist as hole carriers. These one-electron oxidized molecules behave as electrophilic species and can react with other host molecules. Therefore, the stability of compounds in their oxidized states was evaluated using cyclic voltammetry (CV). In CXD, new peaks were observed with repeated insertions on the oxidation side. This is thought to be because electrophilic species such as radical cations generated by the oxidation of CXD underwent chemical reactions such as electrophilic substitution, generating new molecules. On the other hand, no new peaks were observed with repeated insertions in exemplary compounds A-1 and A-40, in which groups other than hydrogen atoms are introduced at R2 and R8 of general formula [1], and exemplary compounds C-1 and C-19, in which groups other than hydrogen atoms are introduced at R3 and R9 of general formula [1]. These results are summarized in Table 1.

[0019] Cyclic voltammetry (CV) was performed in a 0.1 M tetrabutylammonium perchlorate solution of acetonitrile, with an Ag / Ag reference electrode. + The counter electrode was made of Pt, and the working electrode was made of glassy carbon. The insertion rate during repeated insertions was 1.0 V / s. The measurement equipment used was an ALS Model 660C electrochemical analyzer.

[0020] [Table 1]

[0021] By introducing groups other than hydrogen atoms at specific positions in the CXD skeleton, the stability in the oxidized state was improved. The reason for this is presumed to be as follows: The CXD skeleton has a phenolic oxygen atom, and the electron density on its para position, i.e., the carbon atoms to which R2 and R8 in general formula [1] are bonded (referred to as C2 and C10, respectively), is particularly high. Therefore, C2 and C10 are in a state where they are easily attacked by electrophilic species to form bonds. In the case of CXD, only hydrogen atoms are bonded to the carbon atoms adjacent to C2 and C10, respectively, so electrophilic species can attack C2 and C10 without any steric hindrance. On the other hand, in compounds in which groups other than hydrogen atoms are introduced at R2 and R8 in general formula [1], and in compounds in which groups other than hydrogen atoms are introduced at R3 and R9 in general formula [1], the attack on C2 and C10 by electrophilic species is reduced due to the steric hindrance of the groups other than hydrogen atoms. As a result, the compounds of this embodiment were stable in the oxidized state without undergoing chemical reactions.

[0022] Here, it is known that the electron density is high not only at the para position of the phenolic oxygen atom but also at the ortho position. However, due to the steric hindrance of the phenolic oxygen atom itself, the carbon atom at the ortho position is less susceptible to attack by large electrophilic species. In fact, the results in Table 1 show that in compounds with a CXD skeleton, no new peaks are observed in CV even without introducing a group other than a hydrogen atom at the ortho position (example compounds A-1, A-40, C-1, C-19). Therefore, from the viewpoint of decomposition by electrophilic species, introducing a group other than a hydrogen atom at least at the para position (C2, C10) or at carbon atoms adjacent to C2, C10 is highly effective and preferable.

[0023] Examples of carbon atoms adjacent to C2 and C10 include the carbon atoms to which R3 and R9 are bonded in general formula [1], and the carbon atoms to which R1 and R7 are bonded (referred to as C1 and C9, respectively). Introducing groups other than hydrogen atoms to C1 and C9 can cause steric repulsion with the oxygen atom of the carbonyl group, leading to strain throughout the molecule and potentially lowering the molecular bond energy. In such cases, if high excitation energy is applied in the light-emitting layer of the organic light-emitting device, the molecule may decompose due to bond cleavage, potentially reducing its durability. Therefore, introducing groups other than hydrogen atoms to the carbon atoms to which R3 and R9 are bonded is preferable from the viewpoint of durability.

[0024] It is preferable that any group other than the hydrogen atom introduced into at least one of R2, R3, R8, and R9 is bonded to the CXD skeleton by a carbon-carbon bond with high bond energy. Examples of such groups other than the hydrogen atom include substituted or unsubstituted alkyl groups, substituted or unsubstituted aryl groups, and substituted or unsubstituted heterocyclic groups. In this carbon-carbon bond, the carbon atoms of the CXD skeleton are sp 2 Because they are hybrid orbitals, the carbon atoms of the groups other than hydrogen atoms are sp 3 Rather than hybrid orbitals, sp 2 Hybrid orbitals are preferable because they have higher bond energies. Examples of such groups other than hydrogen atoms include substituted or unsubstituted aryl groups and substituted or unsubstituted heterocyclic groups.

[0025] From the above, it can be seen that the organic compound of this embodiment is chemically more stable in the oxidized state than CXD, and its durability is improved when used as a host molecule in the light-emitting layer of an organic light-emitting device. Furthermore, it was found that not only the durability but also the luminous efficiency of the organic light-emitting device is improved. Although the detailed mechanism is not clear, it is presumed that the introduction of groups other than hydrogen atoms reduces excessive aggregation and stacking of the CXD skeleton, making it difficult for exciton deactivation sites to form.

[0026] The following are examples of specific structural formulas of the organic compounds of this embodiment. However, the present invention is not limited to these.

[0027] [ka]

[0028] [ka]

[0029] [ka]

[0030] [ka]

[0031] [ka]

[0032] [ka]

[0033] [ka]

[0034] Compounds belonging to Group A are compounds in which R2 and R8 are alkyl groups, aryl groups, or heterocyclic groups. Compounds belonging to Group A are preferable because, as a group other than a hydrogen atom is directly bonded to the para position of the phenolic oxygen atom, they have even higher chemical stability. In other words, Group A is a group of compounds that have even higher durability when used in organic light-emitting devices. Furthermore, A-24 to A-39 and A-52 to A-54 are compounds having heterocyclic groups, and the HOMO and LUMO levels can be adjusted.

[0035] Compounds belonging to Group B are those in which R2 and R9, or R3 and R8, are alkyl groups, aryl groups, or heterocyclic groups. In Group B compounds, a group other than a hydrogen atom is bonded to one of the para positions of the phenolic oxygen atom, and a group other than a hydrogen atom is bonded to one of the adjacent carbon atoms at the para position. Therefore, Group B compounds have the second highest chemical stability after Group A and exhibit higher durability when used in organic light-emitting devices. Furthermore, compounds B-5, B-6, B-10, and B-11 are heterocyclic compounds that can adjust the HOMO and LUMO levels.

[0036] Compounds belonging to group C are those in which R3 and R9 are alkyl groups, aryl groups, or heterocyclic groups. Because groups other than hydrogen atoms are bonded to the carbon atoms adjacent to the para position of the phenolic oxygen atom, group C has the second highest chemical stability after group B, and when used in organic light-emitting devices, it is a group of compounds that exhibits higher durability. Furthermore, C-15 to C-18 and C-24 to C-26 are groups of compounds that have heterocyclic groups, and the HOMO and LUMO levels can be adjusted.

[0037] Compounds belonging to group D are those in which one of R2, R3, R8, or R9 is an alkyl group, an aryl group, or a heterocyclic group. Group D, particularly D-2 to D-7, has a para position of the phenolic oxygen atom that is not protected by groups other than the hydrogen atom, so its chemical stability is not as high as groups A to C. However, it is a group of compounds in which sublimation is improved and HOMO and LUMO levels can be easily adjusted.

[0038] Organic light-emitting diodes The organic light-emitting element of this embodiment comprises a pair of electrodes and a light-emitting layer disposed between the pair of electrodes, wherein the light-emitting layer preferably comprises a first compound, preferably a host, and a second compound, preferably a guest.

[0039] A specific element configuration of the organic light-emitting element of this embodiment is a multilayer element configuration in which electrode layers and organic compound layers shown in (a) to (f) below are sequentially stacked on a substrate. In all element configurations, the organic compound layer always includes a light-emitting layer having a light-emitting material. (a) Anode / Emitting layer / Cathode (b) Anode / Hole transport layer / Emitting layer / Electron transport layer / Cathode (c) Anode / Hole transport layer / Emitting layer / Electron transport layer / Electron injection layer / Cathode (d) Anode / Hole injection layer / Hole transport layer / Emitting layer / Electron transport layer / Cathode (e) Anode / Hole injection layer / Hole transport layer / Emitting layer / Electron transport layer / Electron injection layer / Cathode (f) Anode / Hole transport layer / Electron blocking layer / Emitting layer / Hole blocking layer / Electron transport layer / Cathode However, these examples of device configurations are merely very basic configurations, and device configurations are not limited to these. For example, a variety of layer configurations can be adopted, such as providing an insulating layer, adhesive layer, or interference layer at the interface between the electrode and the organic compound layer, having an electron transport layer or hole transport layer composed of two layers with different ionization potentials, or having a light-emitting layer composed of two layers of different light-emitting materials.

[0040] Furthermore, the light-emitting layer may be single-layer or multi-layer. Multi-layer means a state in which one light-emitting layer is stacked with another light-emitting layer. For example, a light-emitting layer containing the organic compound of this embodiment represented by general formula [1], which is a host molecule, and a guest molecule may be stacked with another light-emitting layer that emits a different color from the light-emitting color emitted by this light-emitting layer. In this case, the light-emitting color may be white or an intermediate color.

[0041] In the device configurations shown in (a) to (f) above, configuration (f) is preferred because it has both an electron blocking layer and a hole blocking layer. In other words, in configuration (f), which has both an electron blocking layer and a hole blocking layer, both hole and electron carriers can be reliably confined within the light-emitting layer, resulting in an organic light-emitting element with no carrier leakage and high light-emitting efficiency.

[0042] The method of extracting light from the light-emitting layer (device configuration) can be either a so-called bottom emission method, where light is extracted from the electrode on the substrate side, or a so-called top emission method, where light is extracted from the opposite side of the substrate. A double-sided extraction method, where light is extracted from both the substrate side and the opposite side of the substrate, can also be employed.

[0043] In the organic light-emitting device of this embodiment, the organic compound of this embodiment is preferably contained in the light-emitting layer of the organic compound layer. In this case, the compound contained in the light-emitting layer has different uses depending on its concentration in the light-emitting layer. Specifically, it is divided into a main component and a minor component depending on its concentration in the light-emitting layer.

[0044] The main component compound is the compound with the highest mass ratio (concentration) among the compounds contained in the light-emitting layer, and is also called the host compound. The host compound is a compound that exists as a matrix around the light-emitting material in the light-emitting layer, and is mainly responsible for transporting carriers to the light-emitting material and providing excitation energy to the light-emitting material.

[0045] Furthermore, the minor components are compounds other than the main component, and depending on their function, they can be called guests (dopants), luminescence assisting materials, or charge injection materials. A guest, a type of minor component, is the compound (luminescent material) that is primarily responsible for luminescence in the luminescent layer. A luminescence assisting material, also a type of minor component, is a compound that assists the luminescence of the guest, and is a compound whose mass ratio (concentration) in the luminescent layer is smaller than that of the host. Due to its function, the luminescence assisting material is also called a secondary host.

[0046] The host concentration is preferably 50% to 99% by mass, and more preferably 70% to 99% by mass, based on the total amount of constituent materials of the light-emitting layer. The guest concentration is preferably 0.01% to less than 50% by mass, and more preferably 0.1% to 20% by mass, based on the total amount of constituent materials of the light-emitting layer. From the viewpoint of reducing concentration quenching, the guest concentration is particularly preferably 10% by mass or less. The concentration of the light-emitting assist material is preferably 0.1% to less than 50% by mass, and more preferably 1% to less than 50% by mass, based on the total amount of constituent materials of the light-emitting layer.

[0047] The guest material may be uniformly distributed throughout the entire layer where the host matrix is ​​located, or it may be distributed in a concentration gradient. Alternatively, the guest material may be partially distributed in specific regions within the layer, so that the luminescent layer has regions containing only the host and no guest material.

[0048] In this embodiment, it is preferable to include the organic compound of this embodiment as a host in the light-emitting layer. In addition to the first and second compounds, the light-emitting layer may also contain a third compound (second host) for the purpose of assisting in the transfer of excitons and carriers.

[0049] (2) The first compound The first compound is preferably a host. The first compound is preferably the organic compound of this embodiment represented by general formula [1].

[0050] (3) Second compound The second compound is preferably a guest. Guest molecules mainly related to the light-emitting function include condensed ring compounds (such as 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-quinolinolato)aluminum, iridium complexes, platinum complexes, rhenium complexes, copper complexes, europium complexes, ruthenium complexes, and polymer derivatives such as poly(phenylene vinylene) derivatives, poly(fluorene) derivatives, poly(phenylene) derivatives, etc. Specific examples of the compounds used as the light-emitting material are shown below, but of course, they are not limited to these. <​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​​m is an integer between 1 and 3 (inclusive), and n is an integer between 0 and 2 (inclusive). However, if M is iridium, then m+n=3, and if M is platinum, then m+n=2.

[0056] Substructure M(L) m This is shown by the following general formula [2-1]. [ka]

[0057] In equation [2-1], R 21 ~R 28 R is independently selected from hydrogen atoms, deuterium atoms, halogen atoms, substituted or unsubstituted alkyl groups, substituted or unsubstituted alkoxy groups, substituted or unsubstituted silyl groups, substituted or unsubstituted aryl groups, substituted or unsubstituted heterocyclic groups, substituted or unsubstituted amino groups, substituted or unsubstituted aryloxy groups, substituted or unsubstituted heteroaryloxy groups, and cyano groups. 21 ~R 28 These elements may be joined together to form a ring.

[0058] Examples of halogen atoms include, but are not limited to, fluorine, chlorine, bromine, and iodine. Among these, fluorine atoms are preferred.

[0059] Examples of alkyl groups include, but are not limited to, methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, secondary butyl, octyl, cyclohexyl, 1-adamantyl, and 2-adamantyl groups.

[0060] Examples of alkoxy groups include, but are not limited to, methoxy, ethoxy, propoxy, 2-ethyl-octyloxy, and benzyloxy groups.

[0061] Examples of silyl groups include, but are not limited to, trimethylsilyl and triphenylsilyl groups.

[0062] Examples of aryl groups include, but are not limited to, phenyl, naphthyl, indenyl, biphenyl, terphenyl, fluorenyl, phenanthryl, fluoranthenyl, and triphenylenyl groups.

[0063] Examples of heterocyclic groups include, but are not limited to, pyridyl, pyrimidyl, pyrazyl, triazolyl, oxazolyl, oxadiazolyl, thiazolyl, thiadiazolyl, carbazolyl, acridinyl, phenanthrolyl, dibenzofuranyl, and dibenzothiophenyl groups. The heterocyclic group is preferably a heteroaryl group and preferably a group bonded by carbon atoms.

[0064] 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, and carbazolyl group.

[0065] Examples of aryloxy groups and heteroaryloxy groups include, but are not limited to, phenoxy groups and thienyloxy groups.

[0066] Examples of substituents that may further be alkyl groups, alkoxy groups, silyl groups, aryl groups, heterocyclic groups, amino groups, aryloxy groups, and heteroaryloxy groups include, but are not limited to, deuterium atoms; halogen atoms such as fluorine, chlorine, bromine, and iodine; alkyl groups such as methyl, ethyl, n-propyl, isopropyl, n-butyl, and tert-butyl groups; alkoxy groups such as methoxy, ethoxy, and propoxy groups; amino groups such as dimethylamino, diethylamino, dibenzylamino, diphenylamino, and ditolylamino groups; aryloxy groups such as phenoxy groups; aromatic hydrocarbon groups such as phenyl and biphenyl groups; heterocyclic groups such as pyridyl and pyrrolyl groups; cyano, hydroxyl, and thiol groups.

[0067] Also, adjacent R 21 ~R 28 Preferably, adjacent R 21 ~R 24 or adjacent R 25 ~R 28 These may be joined to each other to form a ring. Adjacent R 21 ~R 28 The statement that R is a link to another is that R 21 and R 22 , R 22 and R 23 , R 23 and R 24 A ring formed by the bonding of R 21 ~R 24 The benzene ring to which R is bonded forms a fused ring, or R 25 and R 26 , R 26 and R 27 , R 27 and R 28 A ring formed by the bonding of R 25 ~R 28 This means that the pyridine ring to which is bonded forms a fused ring. 21 ~R 28 The ring formed by the bonding of these elements may be an aromatic ring.

[0068] Substructure M(L') nThis is shown by the following general formula [2-2]. [ka]

[0069] In equation [2-2], R 39 ~R 41 Each of these groups is independently selected from a hydrogen atom, a deuterium atom, a halogen atom, 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, a substituted or unsubstituted amino group, a substituted or unsubstituted aryloxy group, a substituted or unsubstituted heteroaryloxy group, and a cyano group.

[0070] Specific examples of halogen atoms, alkyl groups, alkoxy groups, silyl groups, aryl groups, heterocyclic groups, amino groups, aryloxy groups, and heteroaryloxy groups include R 21 ~R 28 Examples of substituents that alkyl groups, alkoxy groups, silyl groups, aryl groups, heterocyclic groups, amino groups, aryloxy groups, and heteroaryloxy groups may further have include R 21 ~R 28 Examples similar to those described above, but not limited to them, are listed.

[0071] Among the organometallic complexes represented by the general formula [2], the substructure M(L) m Organometallic complexes having three or more fused rings are preferred. This is because the fused ring framework of three or more rings improves planarity, promotes energy transfer from the host molecule, and leads to higher efficiency and improved durability. Examples of three or more fused rings include phenanthrene rings, triphenylene rings, benzofluorene rings, dibenzofuran rings, dibenzothiophene rings, benzonaphthofuran rings, benzonaphthothiophene rings, benzoisoquinoline rings, and naphthoquinoline rings.

[0072] In addition, in the general formula [2-1], R 22 , R 23 , R 26 , R 27 Preferably, at least one of these groups is a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group. This is because, as mentioned above, it improves the planarity of the organometallic complex.

[0073] Below are the partial structures M(L) of the guest organometallic complex. m Specific examples are given below, but the examples are not limited to these. In the specific examples shown below, coordination bonds are indicated by straight lines, dotted lines, or arrows.

[0074] [ka]

[0075] [ka]

[0076] In the above general formulas [Ir-5] to [Ir-8], [Ir-15] to [Ir-16], X' is selected from an oxygen atom, a sulfur atom, a substituted or unsubstituted carbon atom, or a substituted or unsubstituted nitrogen atom.

[0077] The general formulas [Ir-2] through [Ir-8] are given by adjacent R 21 ~R 24 However, they are bonded to each other to form a ring. The general formulas [Ir-9] to [Ir-16] are given by adjacent R 25 ~R 28 However, they are bonded to each other to form a ring. Also, the general formulas [Ir-3] to [Ir-8] are R 21 ~R 24 At least one of the groups is a phenyl group or a naphthyl group, forming a ring with an adjacent group. General formulas [Ir-11] to [Ir-16] are R 25 ~R 28At least one of the groups is a phenyl group or a naphthyl group, forming a ring with the adjacent group. Therefore, the general formulas [Ir-3] to [Ir-8], [Ir-11] to [Ir-16] may or may not have an aryl group or a heterocyclic group.

[0078] Substructure M(L) m Among the metal complexes represented by the above general formulas [Ir-1] to [Ir-16], a more preferable is a metal complex having three or more fused rings as ligands. Specifically, the substructure M(L) m These are metal complexes represented by the general formulas [Ir-3] to [Ir-8] and [Ir-11] to [Ir-16] above. Specific examples are shown below, but are not limited to these.

[0079] [ka]

[0080] [ka]

[0081] [ka]

[0082] [ka]

[0083] [ka]

[0084] [ka]

[0085] [ka]

[0086] [ka]

[0087] [ka]

[0088] [ka]

[0089] [ka]

[0090] [ka]

[0091] [ka]

[0092] [ka]

[0093] [ka]

[0094] [ka]

[0095] Examples of compounds belonging to groups AA through BB are substructure M(L) mThese are metal complexes represented by the general formula [Ir-3], and are compounds having at least a phenanthrene ring as a ligand. Because the fused ring consists of SP2 hybrid orbitals, these compounds are particularly stable.

[0096] Examples of compounds belonging to the CC group include those with substructure M(L). m These are metal complexes represented by the general formula [Ir-4], and are compounds having at least a triphenylene ring as a ligand. These compounds are particularly stable because the fused ring consists of SP2 hybrid orbitals.

[0097] Examples of compounds belonging to the DD group are those with substructure M(L) m These are metal complexes represented by general formulas [Ir-5] to [Ir-8], and are compounds having at least a dibenzofuran ring, a dibenzothiophene ring, a benzonaphthofuran ring, or a benzonaphthothiophene ring as a ligand. These compounds contain oxygen and sulfur atoms in the fused ring, and the abundant lone pairs of electrons on these atoms can enhance charge transport, making them particularly well-suited for adjusting carrier balance.

[0098] Examples of compounds belonging to the EE group to the GG group are substructure M(L) m These compounds are metal complexes represented by the general formulas [Ir-6] to [Ir-8] and have at least one benzofluorene ring as a ligand. Because these compounds have substituents at the 9-position of the fluorene ring perpendicular to the in-plane direction of the fluorene ring, the overlapping of fused rings can be particularly reduced. For this reason, they are compounds with particularly excellent sublimation properties.

[0099] Examples of compounds belonging to the HH group include those with substructure M(L). m These are metal complexes represented by general formulas [Ir-11] to [Ir-13], and are compounds having at least a benzoisoquinoline ring as a ligand. These compounds contain a nitrogen atom in the fused ring, and the lone pairs of electrons and high electronegativity of these atoms can enhance charge transport, making them particularly suitable for adjusting the carrier balance.

[0100] Examples of compounds belonging to group II include those with substructure M(L). m These are metal complexes represented by the general formula [Ir-14], and are compounds having at least a naphthoisoquinoline ring as a ligand. These compounds contain a nitrogen atom in the fused ring, and the lone pairs of electrons and high electronegativity of these atoms can enhance charge transport, making them particularly suitable for adjusting the carrier balance.

[0101] (4) Other compounds The organic light-emitting element according to this embodiment may be used together with conventionally known low-molecular-weight and high-molecular-weight hole-injection compounds or hole-transport compounds, host compounds, luminescent compounds, electron-injection compounds or electron-transport compounds, etc., as needed. Examples of these compounds are listed below.

[0102] 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 reduce film quality degradation such as crystallization in organic light-emitting devices. 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.

[0103] [ka]

[0104] The light-emitting layer may contain a third compound other than the organic compound of this embodiment as a light-emitting layer host or light-emitting assist material. Examples of the third compound include aromatic hydrocarbon compounds or their derivatives, as well as carbazole derivatives, azine derivatives, xanthone derivatives, dibenzofuran derivatives, dibenzothiophene derivatives, organoaluminum complexes such as tris(8-quinolinolate)aluminum, and organoberylium complexes.

[0105] In particular, materials having a carbazole skeleton, materials having a triphenylene ring in their skeleton, and materials having a dibenzothiophene skeleton are preferred as assisting materials. This is because these materials have high electron-donating and electron-withdrawing properties, making it easy to adjust the HOMO and LUMO levels. Since the organic compound according to this embodiment has a CXD skeleton, the HOMO and LUMO levels tend to decrease. Therefore, materials having the above-mentioned skeletons that can adjust the HOMO and LUMO levels are particularly preferred as assisting materials. When these assisting materials are combined with the organic compound of this embodiment, a good carrier balance can be achieved.

[0106] The following are specific examples of compounds used as luminescent layer hosts or luminescence assist materials contained in the luminescent layer, but are not limited to these. Among the specific examples below, EM32 to EM38 are preferred as assist materials because they have a carbazole skeleton. EM10 to EM14, EM32, and EM39 are preferred as assist materials because they have a triphenylene ring in their skeleton. EM13, EM14, and EM28 are preferred as assist materials because they have a dibenzothiophene skeleton.

[0107] [ka]

[0108] 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. Specific examples of compounds used as electron-transporting materials are shown below, but are of course not limited to these.

[0109] [ka]

[0110] (5) Configuration of 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 second electrode. 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.

[0111] [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.

[0112] [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.

[0113] 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.

[0114] 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.

[0115] 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.

[0116] 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.

[0117] 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.

[0118] [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.

[0119] 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.

[0120] 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.).

[0121] 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.

[0122] 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.

[0123] 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.

[0124] [Protective layer] A protective layer may be provided on the second electrode. For example, by bonding glass with a desiccant to the second electrode, 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 second electrode to reduce the intrusion of water and other substances into the organic compound layer. For example, after forming the second electrode, 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 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.

[0125] [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.

[0126] [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.

[0127] 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.

[0128] [Microlens] An organic light-emitting element or 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 element or 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.

[0129] 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.

[0130] [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.

[0131] [Pixel circuit] An organic light-emitting device having an organic light-emitting element may have a pixel circuit connected to the organic 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 driving circuit has a pixel circuit for each pixel. The pixel circuit may include 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.

[0132] 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. The slope of the current-voltage characteristic of the transistors constituting the pixel circuit may be smaller than the slope of the current-voltage characteristic of the transistors constituting the display control circuit. The slope of the current-voltage characteristic can be measured by the so-called Vg-Ig characteristic. The transistors constituting the pixel circuit are transistors connected to the light-emitting element, such as the first light-emitting element.

[0133] [Pixels] An organic light-emitting device having an organic light-emitting element may have a plurality of pixels. Each pixel may have subpixels that emit light of a different color from the others. The subpixels may each have, for example, RGB light-emitting colors.

[0134] A pixel emits light from 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. The distance between subpixels may be 10 μm or less, and specifically, it may be 8 μm, 7.4 μm, 6.4 μm.

[0135] 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.

[0136] (6) Apparatus using organic light-emitting elements The organic light-emitting element according to this embodiment 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.

[0137] The display device may also be an image information processing device having an image input unit that receives image information from an area CCD, linear CCD, memory card, etc., an information processing unit that processes the input information, and displays the input image on a display unit. The display device may have a plurality of pixels, and at least one of the plurality of pixels may have the organic light-emitting element of this embodiment and a transistor connected to the organic light-emitting element. In this case, the substrate may be a semiconductor substrate such as silicon, and the transistor may be a MOSFET formed on the substrate.

[0138] 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.

[0139] Next, a display device according to this embodiment will be described with reference to the drawings. 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 the organic light-emitting element. The transistor is an example of an active element. The transistor may be a thin-film transistor (TFT).

[0140] 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 10 has a reflective electrode which is a first electrode 2 on an interlayer insulating layer 1, an insulating layer 3 covering the end of the first electrode 2, an organic compound layer 4 covering the first electrode 2 and the insulating layer 3, a transparent electrode which is a second electrode 5, a protective layer 6, and a color filter 7.

[0141] 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 2 may be electrically connected via a contact hole or the like (not shown).

[0142] The insulating layer 3 is also called a bank or pixel isolation layer. It covers the edge of the first electrode 2 and surrounds the first electrode 2. The portion not covered by the insulating layer 3 is in contact with the organic compound layer 4 and becomes the light-emitting region.

[0143] 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.

[0144] The second electrode 5 may be a transparent electrode, a reflective electrode, or a semi-transparent electrode.

[0145] The protective layer 6 reduces the penetration of moisture into the organic compound layer 4. Although the protective layer 6 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.

[0146] The color filter 7 is classified into 7R, 7G, and 7B according to its color. The color filter 7 may be formed on a planarization film (not shown). The color filter 7 may also have a resin protective layer (not shown). Alternatively, the color filter 7 may be formed on a protective layer 6. Or it may be bonded to an opposing substrate such as a glass substrate after being placed on it.

[0147] The display device 100 in Figure 1(b) includes an organic light-emitting element 26 and a TFT 18, which is 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 such as the TFT 18 is placed on the insulating layer 12, and the active element has a gate electrode 13, a gate insulating film 14, and a semiconductor layer 15. The TFT 18 has 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 constituting the organic light-emitting element 26 are connected via a contact hole 20.

[0148] Furthermore, the method of electrical connection between the electrodes (anode 21, cathode 23) included in the organic light-emitting element 26 and the electrodes (source electrode 17, drain electrode 16) included in the TFT 18 is not limited to the configuration shown in Figure 1(b). In other words, it is sufficient if either the anode 21 or the cathode 23 is electrically connected to either the source electrode 17 or the drain electrode 16 of the TFT 18.

[0149] In the display device 100 shown in Figure 1(b), the organic compound layer 22 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 26.

[0150] In the display device 100 shown in Figure 1(b), a transistor is used as the switching element, but other switching elements such as MIM elements may be used instead.

[0151] Furthermore, the transistor used in the display device 100 in Figure 1(b) is not limited to a thin-film transistor having an active layer on the insulating surface of the substrate, but may also be a transistor using a single-crystal silicon wafer. 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.

[0152] 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.

[0153] 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.

[0154] 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 may not 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.

[0155] 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.

[0156] 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.

[0157] 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.

[0158] 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.

[0159] 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 this embodiment, 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.

[0160] 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.

[0161] 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 1202 may also be a biometric recognition unit that recognizes a fingerprint to unlock the device, etc. An electronic device having a communication unit can also be called a communication device. The electronic device 1200 may further have a camera function by including a lens and an image sensor. The image captured by the camera function is displayed on the display unit 1201. Examples of electronic devices 1200 include smartphones and laptop computers.

[0162] 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 a light-emitting element according to this embodiment. The display device 1300 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 lower edge of the frame 1301 may also serve as the base. In addition, the frame 1301 and the display unit 1302 may be curved. The radius of curvature may be 5000 mm or more and 6000 mm or less.

[0163] 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 elements 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 by 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.

[0164] 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, and an optical filter 1404 and a light diffusion unit 1405 that transmit light emitted from the light source 1402. The light source 1402 may have an organic light-emitting element according to this embodiment. The optical filter 1404 may be a filter that improves the color rendering of the light source. The light diffusion unit 1405 can effectively diffuse the light from the light source, such as for lighting up, and deliver light over a wide area. The optical filter 1404 and the light diffusion unit 1405 may be provided on the light-emitting side of the lighting. A cover may be provided on the outermost part as needed.

[0165] The lighting device is, for example, a device for illuminating a room. The lighting device may emit white light, daylight white light, or any other color from blue to red. It may have a dimming circuit to adjust the brightness and a color tuning circuit to adjust the color of the emitted light. The lighting device may have the organic light-emitting element of this embodiment and a power supply circuit connected thereto. The power supply circuit is a circuit that converts AC voltage to DC voltage. White has a color temperature of 4200K, and daylight white has a color temperature of 5000K. The lighting device may have a color filter.

[0166] 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.

[0167] 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.

[0168] The taillight 1501 may have an organic light-emitting element according to this embodiment. The taillight 1501 may have a protective member to protect the organic light-emitting 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.

[0169] The automobile 1500 may have a body 1503 and windows 1502 attached thereto. The windows 1502 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.

[0170] The mobile body according to this embodiment may be a ship, aircraft, drone, etc. The mobile body may have a body and a light fixture installed on the body. The light fixture may emit light to indicate the position of the body. The light fixture has an organic light-emitting element according to this embodiment.

[0171] 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.

[0172] Figure 6(a) is a schematic diagram showing an example of a wearable device according to one embodiment of the present invention. Using Figure 6(a), we will explain 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 side of the lens 1601 of the glasses 1600. In addition, the display devices of each embodiment described above are provided on the back surface side of the lens 1601.

[0173] 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. 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.

[0174] Figure 6(b) is a schematic diagram showing another example of a wearable device according to one embodiment of the present invention. Using Figure 6(b), we will describe 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 corresponding to the imaging device 1602 in Figure 6(a) 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 in the control device 1612, and an image is projected onto the lens 1611. The control device 1612 functions as a power supply that supplies power to the imaging device and the display device, and also controls the operation of the imaging device and the display device.

[0175] The control device 1612 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 user's eyeball that is fixated on the displayed image. An imaging unit having 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 a planar view, the degradation of image quality is reduced. The user's gaze toward the displayed image is detected from the image of the eyeball obtained by imaging with infrared light. Any known method can be applied to gaze detection using the image of the eyeball. As an example, a gaze detection method based on the Purkinje image obtained by the reflection of irradiated light from the cornea can be used. More specifically, gaze detection processing based on the pupil-corneal reflection method is performed. Using the pupil-corneal reflection method, the user's gaze is detected by calculating a gaze vector representing the orientation (rotation angle) of the eyeball based on the pupil image and Purkinje image included in the image of the eyeball.

[0176] A display device according to one embodiment of the present invention has 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. Specifically, the display device determines a first field of view area that the user is fixated on and a second field of view area other than the first field of view area, based on the gaze information. The first field of view area and the second field of view area 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. In the display area of ​​the display device, the display resolution of the first field of view area may be controlled to be higher than the display resolution of the second field of view area. In other words, the resolution of the second field of view area may be lower than that of the first field of view area.

[0177] 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.

[0178] 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.

[0179] 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.

[0180] 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 contains toner or the like. The charging unit 30 charges the photoreceptor 27. The transfer unit 32 transfers the developed image to a recording 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.

[0181] Figures 7(b) and 7(c) are diagrams showing the exposure light source 28, schematic diagrams showing how multiple light-emitting units 36 are arranged on a long substrate. The arrow 37 is parallel to the axis of the photoreceptor and represents the column direction 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 and second columns. The first and second columns are located 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.

[0182] As described above, by using the device employing the organic light-emitting element according to this embodiment, stable display with good image quality is possible even during long-term display.

[0183] ≪Included components≫ This embodiment includes the following configuration. (Composition 1) An organic compound characterized by being represented by the above general formula [1]. (Configuration 2) The organic compound according to configuration 1, characterized in that at least one of R2, R3, R8, and R9 is selected from a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group. (Composition 3) The organic compound according to configuration 1 or 2, characterized in that at least one of R2, R3, R8, and R9 is selected from substituted or unsubstituted aryl groups and substituted or unsubstituted heterocyclic groups. (Composition 4) The organic compound according to configuration 1 or 2, characterized in that at least two of R2, R3, R8, and R9 are selected from substituted or unsubstituted alkyl groups, substituted or unsubstituted aryl groups, and substituted or unsubstituted heterocyclic groups. (Composition 5) The organic compound according to configuration 1 or 2, characterized in that at least one of R2 and R3 and at least one of R8 and R9 are selected from a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group. (Composition 6) The organic compound according to configuration 5, characterized in that R2 and R8 are selected from substituted or unsubstituted alkyl groups, substituted or unsubstituted aryl groups, and substituted or unsubstituted heterocyclic groups.

[0184] (Composition 7) It comprises a pair of electrodes and a light-emitting layer disposed between the pair of electrodes, The light-emitting layer comprises a first compound and a second compound, The first compound is an organic light-emitting element, characterized in that it is an organic compound according to any one of the components 1 to 6. (Composition 8) The organic light-emitting element according to configuration 7, characterized in that the second compound is an organometallic complex represented by the general formula [2] above. (Composition 9) The organic light-emitting element according to configuration 8, characterized in that M is iridium. (Composition 10) Said partial structure M(L) m The organic light-emitting element according to configuration 8 or 9, characterized by having three or more fused rings. (Composition 11) The organic light-emitting element according to configuration 10, characterized in that the three or more fused rings are any of a phenanthrene ring, a triphenylene ring, a benzofluorene ring, a dibenzofuran ring, a dibenzothiophene ring, a benzonaphthofuran ring, a benzonaphthothiophene ring, a benzoisoquinoline ring, or a naphthoquinoline ring. (Composition 12) In the above general formula [2-1], R 22 , R 23 , R 26 , R 27 The organic light-emitting element according to any one of configurations 8 to 11, characterized in that at least one of them is selected from a substituted or unsubstituted aryl group and a substituted or unsubstituted heterocyclic group.

[0185] (Composition 13) The organic light-emitting element according to any one of configurations 7 to 12, characterized in that the light-emitting layer further contains a third compound. (Composition 14) The organic light-emitting element according to configuration 13, characterized in that the third compound has at least a carbazole skeleton. (Composition 15) The organic light-emitting element according to configuration 13, characterized in that the third compound has at least a triphenylene ring as its skeleton. (Composition 16) The organic light-emitting element according to configuration 13, characterized in that the third compound has at least a dibenzothiophene skeleton. (Composition 17) The organic light-emitting element according to any one of configurations 7 to 16, further comprising another light-emitting layer arranged in lamination with the aforementioned light-emitting layer, wherein the other light-emitting layer emits a color different from the light-emitting color emitted by the aforementioned light-emitting layer. (Composition 18) The organic light-emitting device according to Configuration 17, which is characterized by emitting white light.

[0186] (Configuration 19) A display device having a plurality of pixels, wherein at least one of the plurality of pixels includes the organic light-emitting device according to any one of Configurations 7 to 18 and a transistor connected to the organic light-emitting device. (Configuration 20) An optoelectronic conversion device having an optical unit with a plurality of lenses, an image pickup device that receives light that has passed through the optical unit, and a display unit that displays an image picked up by the image pickup device, wherein the display unit has the organic light-emitting device according to any one of Configurations 7 to 18. (Configuration 21) An electronic device having a display unit with the organic light-emitting device according to any one of Configurations 7 to 18, a housing in which the display unit is provided, and a communication unit provided in the housing for communicating with the outside. (Configuration 22) An illumination device having a light source with the organic light-emitting device according to any one of Configurations 7 to 18 and a light diffusing unit or an optical filter that transmits light emitted by the light source. (Configuration 23) A moving body having a lighting fixture with the organic light-emitting device according to any one of Configurations 7 to 18 and a body on which the lighting fixture is provided. (Configuration 24) An exposure light source of an electrophotographic image forming apparatus, which has the organic light-emitting device according to any one of Configurations 7 to 18.

Example

[0187] Examples will be described below. Note that the present invention is not limited to these.

[0188] <Example 1 (Synthesis of Exemplary Compound A-1)>

Chemical Formula

[0189] [Reaction Step 1 (Synthesis of Intermediate Compound Int1-1)] The reagents and solvents listed below were placed in a 200 mL round-bottom flask. Resorcinol (manufactured by Tokyo Chemical Industry Co., Ltd.): 5.00g (45.4 mmol) 5-Bromo-2-fluorobenzonitrile (manufactured by Tokyo Chemical Industry Co., Ltd.): 19.8g (98.8mmol) Potassium carbonate: 15.0g (108 mmol) Dimethyl sulfoxide: 62 mL

[0190] The reaction solution was heated under nitrogen at 80°C with stirring for 12 hours. After the reaction was complete, the solution was cooled to room temperature, then poured into ice water and stirred for 1 hour. The precipitated solid was collected by filtration, washed with deionized water, and dried in a vacuum dryer at 80°C for 12 hours. The resulting crude product was recrystallized in dichloromethane / heptane solvent to obtain 18.1 g of Int1-1 (yield 85%).

[0191] [Reaction Step 2 (Synthesis of Intermediate Compound Int1-2)] The reagents and solvents listed below were placed in a 200 mL round-bottom flask. Int1-1: 5.00g (10.6 mmol) Sodium hydroxide: 5.32g (133 mmol) Deionized water: 21 mL Ethanol: 80mL

[0192] The reaction solution was heated under nitrogen with stirring for 6 hours under reflux. After the reaction was complete, it was cooled to room temperature, and then 2N hydrochloric acid was added dropwise to the reaction solution until the pH was 1 to 2. The precipitated solid was collected by filtration and dried in a vacuum dryer at 80°C for 12 hours to obtain 5.30 g of Int1-2 (yield 98%).

[0193] [Reaction Step 3 (Synthesis of Intermediate Compounds Int1-3)] The reagents and solvents listed below were placed in a 100 mL round-bottom flask. Int1-2: 5.00g (9.84 mmol) Concentrated sulfuric acid: 17mL

[0194] The reaction solution was heated under nitrogen at 80°C with stirring for 12 hours. After the reaction was complete, it was cooled to room temperature, then the reaction solution was poured onto crushed ice and stirred for 1 hour. The precipitated solid was collected by filtration, washed with deionized water, and dried in a vacuum dryer at 80°C for 12 hours. The resulting crude product was recrystallized in dichloromethane / methanol solvent to obtain 4.18 g of Int1-3 (yield 90%).

[0195] [Reaction Step 4 (Synthesis of Exemplary Compound A-1)] [ka]

[0196] The reagents and solvents listed below were placed in a 50 mL round-bottom flask. Int1-3: 0.500g (1.06 mmol) Phenylboronic acid (manufactured by Tokyo Chemical Industry Co., Ltd.): 0.284g (2.33 mmol) Sodium carbonate: 0.617g (5.83 mmol) Tetrakis(triphenylphosphine)palladium (0): 0.122g (0.106 mmol) Toluene: 10mL Ion-exchanged water: 3 mL

[0197] The reaction solution was heated under nitrogen with stirring for 18 hours under reflux. After the reaction was complete, it was cooled to room temperature, and the organic layer was separated, dried over magnesium sulfate, and filtered. The solvent of the obtained filtrate was removed under reduced pressure, and the precipitated solid was purified by silica gel column (chloroform:heptane = 3:1). The obtained crystals were dried in a vacuum dryer at 80°C for 12 hours to obtain 0.420 g of exemplary compound A-1 (yield 85%).

[0198] MALDI-TOF MS (matrix-assisted ionization-time-of-flight mass spectrometry) revealed the M of this compound. + I confirmed that it was 466.1.

[0199] <Examples 2 to 6 (Synthesis of Exemplary Compounds)> In Reaction Step 4 of Example 1, exemplary compounds shown in Table 2 were synthesized in the same manner as in Example 1, except that phenylboronic acid was changed to the boronic acid compounds shown in Table 2.

[0200] [Table 2]

[0201] <Example 7 (Synthesis of Exemplary Compound C-1)> [Reaction Steps 1 to 3 (Synthesis of Intermediate Compounds Int2-1 to Int2-3)] [Chemical Formula]

[0202] In Reaction Step 1 of Example 1, intermediate compounds Int2-1 to 2-3 were synthesized in the same manner as Reaction Steps 1 to 3 of Example 1, except that 5-bromo-2-fluorobenzonitrile was changed to 4-bromo-2-fluorobenzonitrile.

[0203] [Reaction Step 4 (Synthesis of Exemplary Compound C-1)] [Chemical Formula]

[0204] In Reaction Step 4 of Example 1, exemplary compound C-1 was synthesized in the same manner as Reaction Step 4 of Example 1, except that reaction step intermediate compound Int1-3 was changed to intermediate compound Int2-3.

[0205] <Examples 8 to 12 (Synthesis of Exemplary Compounds)> In Reaction Step 4 of Example 7, exemplary compounds shown in Table 3 were synthesized in the same manner as in Example 7, except that phenylboronic acid was changed to the boronic acid compounds shown in Table 3.

[0206] [Table 3]

[0207] <Examples 13 to 14 (Synthesis of Exemplary Compounds A-40 and C-19)> Exemplary compounds A-40 and C-19 were synthesized in the same manner as in reaction steps 1 to 3 of Example 1, except that in reaction step 1 of Example 1, 5-bromo-2-fluorobenzonitrile was replaced with 5-methyl-2-fluorobenzonitrile (manufactured by Tokyo Chemical Industry Co., Ltd.) or 4-methyl-2-fluorobenzonitrile (manufactured by Tokyo Chemical Industry Co., Ltd.). [ka]

[0208] <Comparative Example 1 (Synthesis of CXD)> CXD was synthesized in the same manner as in reaction steps 1 to 3 of Example 1, except that 5-bromo-2-fluorobenzonitrile was replaced with 2-fluorobenzonitrile (manufactured by Tokyo Chemical Industry Co., Ltd.) in reaction step 1 of Example 1. [ka]

[0209] <Example 15> 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.

[0210] 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, 1.33 × 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 4 onto an ITO substrate. Note that 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.

[0211] [Table 4]

[0212] The characteristics of the obtained device were measured and evaluated. The maximum emission wavelength of the light-emitting element was 522 nm, and the maximum external quantum efficiency (EQE) was 13%.

[0213] Furthermore, the current density is 100 mA / cm². 2 A continuous operation test was conducted, and the time it took for the brightness degradation rate to reach 5% was measured. When the time it took for the brightness degradation rate to reach 5% in Comparative Example 2 was set as the baseline (1.0), the ratio of the 5% brightness degradation time in this example was 1.4.

[0214] 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.

[0215] <Examples 16 to 24, Comparative Example 2> Organic light-emitting devices were fabricated in the same manner as in Example 15, except that the host and guest compounds were appropriately changed to those shown in Table 5. The characteristics of the obtained devices were measured and evaluated in the same manner as in Example 15. The measurement results are shown in Table 5.

[0216] [Table 5]

[0217] <Example 25> An organic light-emitting element was fabricated in the same manner as in Example 15, except that the organic compound layer and electrode layer shown in Table 6 were continuously fabricated.

[0218] [Table 6]

[0219] The characteristics of the obtained element were measured and evaluated in the same manner as in Example 15. The maximum emission wavelength of the light-emitting element was 522 nm, and the maximum external quantum efficiency (EQE) was 19%. Furthermore, when the time at which the brightness degradation rate of Comparative Example 3 reached 5% was set as the baseline (1.0), the 5% brightness degradation time of this example was 1.4 as a ratio.

[0220] <Examples 26 to 34, Comparative Example 3> Organic light-emitting devices were fabricated in the same manner as in Example 25, except that the compounds shown in Table 7 were changed as appropriate. The characteristics of the obtained devices were measured and evaluated in the same manner as in Example 25. The measurement results are shown in Table 7.

[0221] [Table 7]

[0222] As shown in Table 7, by using the organic compound of this embodiment as the host, and further using a material having a carbazole skeleton, triphenylene skeleton, etc., suitable for combination with the organic compound of this embodiment as the second host material, the luminous efficiency and lifetime characteristics of the device were improved. [Explanation of symbols]

[0223] 1: Interlayer insulating layer, 2: First electrode, 3: Insulating layer, 4: Organic compound layer, 5: Second electrode, 6: Protective layer, 7: Color filter, 10: Sub-pixel, 11: Substrate, 12: Insulating layer, 13: Gate electrode, 14: Gate insulating film, 15: Semiconductor layer, 16: Drain electrode, 17: Source electrode, 18: TFT, 19: Insulating film, 20: Contact hole, 21: Anode, 22: Organic compound layer, 23: Cathode, 24: First protective layer, 25: Second protective layer, 26: Organic light-emitting element, 100: Display device

Claims

1. An organic compound characterized by being represented by the following general formula [1]. 【Chemistry 1】 In general formula [1], R 1 ~R 10 R is independently selected from a hydrogen atom, a deuterium atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group. 2 , R 3 , R 8 , R 9 At least one of these is selected from a deuterium atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group.

2. Said R 2 , R 3 , R 8 , R 9 The organic compound according to claim 1, wherein at least one of them is selected from a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, and a substituted or unsubstituted heterocyclic group.

3. The aforementioned R 2 , R 3 , R 8 , R 9 The organic compound according to claim 2, characterized in that at least one of them is selected from substituted or unsubstituted aryl groups and substituted or unsubstituted heterocyclic groups.

4. The aforementioned R 2 , R 3 , R 8 , R 9 The organic compound according to claim 2, characterized in that at least two of them are selected from substituted or unsubstituted alkyl groups, substituted or unsubstituted aryl groups, and substituted or unsubstituted heterocyclic groups.

5. The aforementioned R 2 , R 3 At least one of the above, and the R 8 , R 9 The organic compound according to claim 2, characterized in that at least one of them is selected from a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group.

6. The aforementioned R 2 and R 8 The organic compound according to claim 5, characterized in that is selected from a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group.

7. It comprises a pair of electrodes and a light-emitting layer disposed between the pair of electrodes, The light-emitting layer comprises a first compound and a second compound, The organic light-emitting element is characterized in that the first compound is an organic compound according to any one of claims 1 to 6.

8. The organic light-emitting element according to claim 7, characterized in that the second compound is an organometallic complex represented by the following general formula [2]. M(L) m (L’) n [2] In the general formula [2], M is selected from iridium and platinum. L and L' represent different bidentate ligands, and if there are multiple L or L', they may be the same or different. m is an integer between 1 and 3 (inclusive), and n is an integer between 0 and 2 (inclusive). However, if M is iridium, then m + n = 3, and if M is platinum, then m + n = 2. Partial structure M(L) m This is shown by the following general formula [2-1]. 【Chemistry 2】 In general formula [2-1], R 21 ~R 28 R is independently selected from hydrogen atoms, deuterium atoms, halogen atoms, substituted or unsubstituted alkyl groups, substituted or unsubstituted alkoxy groups, substituted or unsubstituted silyl groups, substituted or unsubstituted aryl groups, substituted or unsubstituted heterocyclic groups, substituted or unsubstituted amino groups, substituted or unsubstituted aryloxy groups, substituted or unsubstituted heteroaryloxy groups, and cyano groups. 21 ~R 28 These elements may be joined together to form a ring. Partial structure M(L') n This is shown by the following general formula [2-2]. 【Transformation 3】 In general formula [2-2], R 39 ~R 41 Each of these groups is independently selected from a hydrogen atom, a deuterium atom, a halogen atom, 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, a substituted or unsubstituted amino group, a substituted or unsubstituted aryloxy group, a substituted or unsubstituted heteroaryloxy group, and a cyano group.

9. The organic light-emitting element according to claim 8, characterized in that M is iridium.

10. Said partial structure M(L) m The organic light-emitting element according to claim 8, characterized in that it has three or more fused rings.

11. The organic light-emitting element according to claim 10, characterized in that the three or more fused rings are any of a phenanthrene ring, a triphenylene ring, a benzofluorene ring, a dibenzofuran ring, a dibenzothiophene ring, a benzonaphthofuran ring, a benzonaphthothiophene ring, a benzoisoquinoline ring, or a naphthoquinoline ring.

12. In the above general formula [2-1], R 22 , R 23 , R 26 , R 27 The organic light-emitting element according to claim 8, characterized in that at least one of them is selected from a substituted or unsubstituted aryl group and a substituted or unsubstituted heterocyclic group.

13. The organic light-emitting element according to claim 7, characterized in that the light-emitting layer further contains a third compound.

14. The organic light-emitting element according to claim 13, characterized in that the third compound has at least a carbazole skeleton.

15. The organic light-emitting element according to claim 13, characterized in that the third compound has at least a triphenylene ring in its skeleton.

16. The organic light-emitting element according to claim 13, characterized in that the third compound has at least a dibenzothiophene skeleton.

17. The organic light-emitting element according to claim 7, further comprising another light-emitting layer arranged in lamination with the aforementioned light-emitting layer, wherein the other light-emitting layer emits a color different from the light-emitting color emitted by the aforementioned light-emitting layer.

18. The organic light-emitting element according to claim 17, characterized in that it emits white light.

19. 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 claim 7 and a transistor connected to the organic light-emitting element.

20. 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 the organic light-emitting element described in claim 7.

21. An electronic device comprising: a display unit having an organic light-emitting element as described in claim 7; a housing on which the display unit is provided; and a communication unit provided in the housing for communicating with the outside.

22. A lighting device characterized by comprising a light source having an organic light-emitting element as described in claim 7, and a light-diffusing section or optical filter that transmits light emitted by the light source.

23. A mobile body characterized by comprising a lamp having an organic light-emitting element as described in claim 7, and a body on which the lamp is provided.

24. An exposure light source for an electrophotographic image forming apparatus, characterized by having the organic light-emitting element described in claim 7.

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