Organic compound, light-emitting device, light-emitting equipment, electronic device and lighting device

Abstract

To provide an organic compound having a small refractive index and hole transportability.SOLUTION: There is provided an organic compound represented by the general formula (G1), where Ar12 represents an aryl group having 6 to 10 carbon atoms for forming a ring and has at least one branched-chain or cyclic alkyl group having 3 to 12 carbon atoms. The total number of carbons of the branched-chain or cyclic alkyl group having 3 to 12 carbon atoms of Ar12 is 6 to 36. In addition, Ar11 and Ar21 represent an arylene group having 6 to 13 carbon atoms for forming a substituted or unsubstituted ring. Further, Ar22 represents an aryl group having 6 to 10 carbon atoms for forming a substituted or unsubstituted ring. Further, n and m each independently represents an integer of 0 or 1. Further, Ar1 represents a phenyl group having at least one alkyl group having 1 to 6 carbon atoms. Ar2 represents a phenyl group having at least one alkyl group having 1 to 6 carbon atoms or an alkyl group having 1 to 4 carbon atoms.SELECTED DRAWING: None

Description

[Technical Field]

[0001] One aspect of the present invention relates to organic compounds, light-emitting elements, light-emitting devices, display modules, lighting modules, display devices, light-emitting devices, electronic equipment, lighting devices, and electronic devices. However, one aspect of the present invention is not limited to the above-mentioned technical fields. The technical fields of one aspect of the invention disclosed herein relate to products, methods, or methods of manufacturing. Alternatively, one aspect of the present invention relates to processes, machines, manufacturers, or compositions of matter. More specifically, examples of the technical fields of one aspect of the present invention disclosed herein include semiconductor devices, display devices, liquid crystal display devices, light-emitting devices, lighting devices, energy storage devices, memory devices, imaging devices, methods for driving them, or methods for manufacturing them. [Background technology]

[0002] The practical application of light-emitting devices (organic electroluminescent devices) that utilize electroluminescence (EL) using organic compounds is progressing. The basic structure of these light-emitting devices is an organic compound layer (EL layer) containing a light-emitting material sandwiched between a pair of electrodes. By applying a voltage to this device, carriers (holes and electrons) are injected, and by utilizing the recombination energy of these carriers, light emission can be obtained from the light-emitting material.

[0003] Because these light-emitting devices are self-emissive, using them as pixels in a display offers advantages over liquid crystal displays, such as higher visibility and the elimination of the need for a backlight, making them suitable as flat-panel display elements. Furthermore, displays using such light-emitting devices can be manufactured to be thin and lightweight, which is a significant advantage. Another characteristic is their extremely fast response speed.

[0004] Furthermore, because these light-emitting devices can form a light-emitting layer continuously in two dimensions, they can produce light in a planar manner. This is a feature that is difficult to obtain with point light sources such as incandescent bulbs and LEDs, or line light sources such as fluorescent lamps, so organic EL devices have high utility as planar light sources that can be applied to lighting and other applications.

[0005] As described above, displays and lighting devices using light-emitting devices are suitable for a variety of electronic devices, and research and development are underway to find light-emitting devices with even better characteristics.

[0006] One of the problems often raised when discussing organic EL devices is their low light extraction efficiency. In particular, attenuation due to reflection caused by differences in refractive index between adjacent layers is a major factor in reducing the device's efficiency. To mitigate this effect, a configuration has been proposed in which a layer made of a low refractive index material is formed inside the EL layer (see, for example, Non-Patent Document 1).

[0007] Light-emitting devices with this configuration can achieve higher light extraction efficiency, and consequently higher external quantum efficiency, than light-emitting devices with conventional configurations. However, forming such a low refractive index layer within the EL layer without adversely affecting other important properties of the light-emitting device is not easy. This is because there is a trade-off between a low refractive index and high carrier transportability or reliability when used in a light-emitting device. This problem stems from the fact that carrier transportability and reliability in organic compounds largely depend on the presence of unsaturated bonds, and organic compounds with many unsaturated bonds tend to have high refractive indices. [Prior art documents] [Non-patent literature]

[0008] [Non-Patent Document 1] Jaeho Lee, et al., "Synergetic electrode architecture for efficient graphene-based flexible organic light-emitting diodes," Nature Communications, June 2, 2016, DOI: 10.1038 / ncomms11791 [Overview of the project] [Problems that the invention aims to solve]

[0009] One aspect of the present invention aims to provide a novel organic compound. Alternatively, one aspect of the present invention aims to provide a novel organic compound having carrier transport properties. Alternatively, one aspect of the present invention aims to provide a novel organic compound having hole transport properties. One aspect of the present invention aims to provide an organic compound with a low refractive index. Alternatively, one aspect of the present invention aims to provide an organic compound with a low refractive index and carrier transport properties. Alternatively, one aspect of the present invention aims to provide an organic compound with a low refractive index and hole transport properties. Alternatively, one aspect of the present invention aims to provide an organic compound with a low refractive index and hole injection properties.

[0010] Alternatively, one aspect of the present invention aims to provide a light-emitting device with high luminous efficiency. Alternatively, one aspect of the present invention aims to provide a light-emitting device, light-emitting apparatus, electronic device, display device, and electronic device, respectively, with low power consumption.

[0011] Furthermore, the description of these problems does not preclude the existence of other problems. Moreover, one aspect of the present invention does not necessarily have to solve all of these problems. Other problems will naturally become clear from the description in the specification, drawings, and claims, and it is possible to extract other problems from the description in the specification, drawings, and claims.

[0012] In one aspect of the present invention, it is only necessary to solve any one of the above problems.

Means for Solving the Problems

[0013] One aspect of the present invention is an organic compound represented by the general formula (G1).

[0014]

Chemical formula

[0015] In the above general formula (G1), Ar 12 represents an aryl group having 6 to 10 carbon atoms forming a ring and having at least one branched or cyclic alkyl group having 3 to 12 carbon atoms. The total number of carbon atoms of the branched or cyclic alkyl group having 3 to 12 carbon atoms possessed by Ar 12 is 6 to 36. Further, Ar 11 represents an arylene group having 6 to 13 carbon atoms forming a substituted or unsubstituted ring. Further, n represents an integer of 0 or 1. Further, Ar 22 represents an aryl group having 6 to 10 carbon atoms forming a substituted or unsubstituted ring. Further, Ar 21 represents an arylene group having 6 to 13 carbon atoms forming a substituted or unsubstituted ring. Further, m represents an integer of 0 or 1. Further, Ar 1 represents a phenyl group having at least one alkyl group having 1 to 6 carbon atoms. Further, Ar 2 represents a phenyl group having at least one alkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 4 carbon atoms. Further, R 1 to R 4 each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Further, one of R 5 to R 8 is a bond directly bonded to a nitrogen atom, and the others each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

[0016] Also, one aspect of the present invention is an organic compound represented by the general formula (G2).

[0017] [ka]

[0018] In the above general formula (G2), Ar 1 This represents a phenyl group having at least one alkyl group with 1 to 6 carbon atoms. Also, Ar 2 R represents a phenyl group having at least one alkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 4 carbon atoms. 1 ~R 4 Each of these independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Also, R 5 ~R 8 One of these is a bond that directly attaches to the nitrogen atom, and the others each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Also, R 10 ~R 14 and R 20 ~R 24 Each of these independently represents a hydrogen atom or a branched or cyclic alkyl group having 3 to 12 carbon atoms. However, R 10 ~R 14 The total number of carbon atoms is between 6 and 36. Also, n and m each independently represent an integer of 0 or 1.

[0019] Furthermore, one aspect of the present invention is an organic compound represented by the general formula (G3).

[0020] [ka]

[0021] In the above general formula (G3), Ar 1 This represents a phenyl group having at least one branched or cyclic alkyl group having 3 to 6 carbon atoms. Also, Ar 2 R represents a phenyl group having at least one branched or cyclic alkyl group having 3 to 6 carbon atoms, or an alkyl group having 1 to 4 carbon atoms. 1 ~R 4Each of these independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Also, R 5 ~R 8 One of these is a bond that directly attaches to the nitrogen atom, and the others each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Also, R 10 ~R 14 and R 20 ~R 24 Each of these independently represents a hydrogen atom or a branched or cyclic alkyl group having 3 to 12 carbon atoms. However, R 10 ~R 14 The total number of carbon atoms is between 6 and 36. Also, m represents an integer of 0 or 1.

[0022] Furthermore, one aspect of the present invention is an organic compound represented by general formula (G4).

[0023] [ka]

[0024] In the above general formula (G4), R 1 ~R 4 Each of these independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Also, R 5 ~R 8 One of these is a bond that directly attaches to the nitrogen atom, and the others each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Also, R 10 ~R 14 and R 20 ~R 24 Each of these independently represents a hydrogen atom or a branched or cyclic alkyl group having 3 to 12 carbon atoms. However, R 10 ~R 14 The total number of carbon atoms is between 6 and 36. Also, R 30 ~R 34 At least one of these represents a branched or cyclic alkyl group having 3 to 6 carbon atoms, and the others represent hydrogen atoms. Also, R 40 ~R 44At least one of these represents a branched or cyclic alkyl group having 3 to 6 carbon atoms, and the others represent hydrogen atoms. Also, m represents an integer of 0 or 1.

[0025] Furthermore, in one aspect of the present invention, in each of the above configurations, R 1 ~R 4 R is a hydrogen atom, 5 ~R 8 It is an organic compound in which one of the bonds is directly bonded to a nitrogen atom, and the other is a hydrogen atom.

[0026] Furthermore, in one aspect of the present invention, in each of the above configurations, R 10 ~R 14 The organic compound is one in which at least one of the groups is a tert-butyl group or a cyclohexyl group.

[0027] Furthermore, in one aspect of the present invention, in each of the above configurations, R 10 , R 12 , and R 14 is a hydrogen atom, and R 11 and R 13 It is an organic compound in which the group is either a tert-butyl group or a cyclohexyl group.

[0028] Furthermore, in one aspect of the present invention, in each of the above configurations, R 10 , R 11 , R 13 , and R 14 is a hydrogen atom, and R 12 It is an organic compound in which the group is either a tert-butyl group or a cyclohexyl group.

[0029] Furthermore, in one aspect of the present invention, the organic compound in each of the above configurations is an organic compound having an ordinary refractive index of 1.50 or more and 1.75 or less for light with a wavelength of 465 nm in the layer made of the organic compound.

[0030] Furthermore, in one aspect of the present invention, the organic compound in each of the above configurations is an organic compound having an ordinary refractive index of 1.50 or more and 1.70 or less for light with a wavelength of 520 nm in the layer made of the organic compound.

[0031] Furthermore, in one aspect of the present invention, the organic compound in each of the above configurations is an organic compound having an ordinary refractive index of 1.45 or more and 1.70 or less for light with a wavelength of 633 nm in the layer made of the organic compound.

[0032] Furthermore, one aspect of the present invention is an organic compound represented by any one of structural formulas (100) to (102).

[0033] [ka]

[0034] Furthermore, one aspect of the present invention is a light-emitting device using organic compounds having the above-described configurations.

[0035] Furthermore, one aspect of the present invention is an electronic device having the above-described light-emitting device and a detection unit, an input unit, or a communication unit.

[0036] Furthermore, one aspect of the present invention is a light-emitting device having the above-described light-emitting device and a transistor or a substrate.

[0037] Furthermore, one aspect of the present invention is a lighting device having the above-described light-emitting device and a housing.

[0038] In this specification, the term "light-emitting device" includes image display devices that use light-emitting devices. Furthermore, modules in which a connector, such as an anisotropic conductive film or TCP (Tape Carrier Package), is attached to a light-emitting device on a substrate, modules in which a printed circuit board is provided at the end of the TCP, or modules in which an IC (integrated circuit) is directly mounted to the light-emitting device using the COG (Chip On Glass) method may also be included as light-emitting devices. Additionally, lighting fixtures and the like may have light-emitting devices. [Effects of the Invention]

[0039] In one aspect of the present invention, a novel organic compound can be provided. Alternatively, in one aspect of the present invention, a novel organic compound having carrier transport properties can be provided. Alternatively, in one aspect of the present invention, a novel organic compound having hole transport properties can be provided. In one aspect of the present invention, an organic compound with a low refractive index can be provided. Alternatively, in one aspect of the present invention, an organic compound with a low refractive index and carrier transport properties can be provided. Alternatively, in one aspect of the present invention, an organic compound with a low refractive index and hole transport properties can be provided. Alternatively, in one aspect of the present invention, an organic compound with a low refractive index and hole implantation properties can be provided. Alternatively, in one aspect of the present invention, an organic compound with a low refractive index that generates large spontaneous polarization during deposition can be provided.

[0040] Alternatively, in one aspect of the present invention, a light-emitting device with high luminous efficiency can be provided. Alternatively, in one aspect of the present invention, a light-emitting device, a light-emitting apparatus, an electronic device, a display device, and an electronic device with low power consumption can each be provided.

[0041] Furthermore, the description of these effects does not preclude the existence of other effects. Moreover, one aspect of the present invention does not necessarily have to possess all of these effects. Other effects will naturally become apparent from the description in the specification, drawings, and claims, and it is possible to extract other effects from the description in the specification, drawings, and claims. [Brief explanation of the drawing]

[0042] [Figure 1] Figures 1(A) to 1(E) illustrate the configuration of a light-emitting device according to an embodiment. [Figure 2] Figures 2(A) to 2(C) illustrate a light-emitting device according to an embodiment. [Figure 3] Figures 3(A) to 3(C) illustrate a method for manufacturing a light-emitting device according to an embodiment. [Figure 4]Figures 4(A) to 4(C) illustrate a method for manufacturing a light-emitting device according to an embodiment. [Figure 5] Figures 5(A) to 5(C) illustrate a method for manufacturing a light-emitting device according to an embodiment. [Figure 6] Figures 6(A) to 6(C) illustrate a method for manufacturing a light-emitting device according to an embodiment. [Figure 7] Figure 7 is a diagram illustrating a light-emitting device according to an embodiment. [Figure 8] Figures 8(A) and 8(B) illustrate a light-emitting device according to an embodiment. [Figure 9] Figures 9(A) and 9(B) illustrate a light-emitting device according to an embodiment. [Figure 10] Figures 10(A) and 10(B) illustrate a light-emitting device according to an embodiment. [Figure 11] Figures 11(A) and 11(B) illustrate a light-emitting device according to an embodiment. [Figure 12] Figures 12(A) to 12(E) illustrate the electronic device according to the embodiment. [Figure 13] Figures 13(A) to 13(E) illustrate the electronic device according to the embodiment. [Figure 14] Figures 14(A) and 14(B) illustrate an electronic device according to an embodiment. [Figure 15] Figures 15(A) and 15(B) illustrate the electronic device according to the embodiment. [Figure 16] Figure 16 is a diagram illustrating an electronic device according to an embodiment. [Figure 17] Figures 17(A) to 17(C) illustrate the light-emitting device and light-receiving device according to the embodiment. [Figure 18] Figure 18 shows the absorption and emission spectra of mmtBuBichPAtBu2FLP(2) in a toluene solution. [Figure 19]Figure 19 shows the MS spectrum of mmtBuBichPAtBu2FLP(2). [Figure 20] Figure 20 shows the measured refractive index data for mmtBuBichPAtBu2FLP(2). [Figure 21] Figure 21 shows the absorption and emission spectra of mmtBuBioBitBu2FLP(2) in a toluene solution. [Figure 22] Figure 22 shows the MS spectrum of mmtBuBioBitBu2FLP(2). [Figure 23] Figure 23 shows the measured refractive index data for mmtBuBioBitBu2FLP(2). [Figure 24] Figure 24 shows the absorption and emission spectra of dchPAtBu2FLP(2) in a toluene solution. [Figure 25] Figure 25 shows the measured refractive index data for dchPAtBu2FLP(2). [Figure 26] Figure 26 is a diagram illustrating the configuration of a light-emitting device according to an embodiment. [Figure 27] Figure 27 shows the measured refractive index data for mmtBuBichPAtBu2FLP(2), FBiFLPB, and oFBiSF. [Figure 28] Figure 28 shows the luminance-current density characteristics of light-emitting device 1, comparative light-emitting device 1-1, and comparative light-emitting device 1-2. [Figure 29] Figure 29 shows the current efficiency-luminance characteristics of light-emitting device 1, comparative light-emitting device 1-1, and comparative light-emitting device 1-2. [Figure 30] Figure 30 shows the luminance-voltage characteristics of light-emitting device 1, comparative light-emitting device 1-1, and comparative light-emitting device 1-2. [Figure 31] Figure 31 shows the current-voltage characteristics of light-emitting device 1, comparative light-emitting device 1-1, and comparative light-emitting device 1-2. [Figure 32] Figure 32 shows the external quantum efficiency-luminance characteristics of light-emitting device 1, comparative light-emitting device 1-1, and comparative light-emitting device 1-2. [Figure 33]Figure 33 shows the emission spectra of light-emitting device 1, comparative light-emitting device 1-1, and comparative light-emitting device 1-2. [Figure 34] Figure 34 shows the change in brightness with respect to the operating time of light-emitting device 1, comparative light-emitting device 1-1, and comparative light-emitting device 1-2. [Figure 35] Figure 35 shows the measured refractive index data for mmtBuBioBitBu2FLP(2), FBiFLPB, and oFBiSF. [Figure 36] Figure 36 shows the luminance-current density characteristics of light-emitting device 2, comparative light-emitting device 2-1, and comparative light-emitting device 2-2. [Figure 37] Figure 37 shows the current efficiency-luminance characteristics of light-emitting device 2, comparative light-emitting device 2-1, and comparative light-emitting device 2-2. [Figure 38] Figure 38 shows the luminance-voltage characteristics of light-emitting device 2, comparative light-emitting device 2-1, and comparative light-emitting device 2-2. [Figure 39] Figure 39 shows the current-voltage characteristics of light-emitting device 2, comparative light-emitting device 2-1, and comparative light-emitting device 2-2. [Figure 40] Figure 40 shows the external quantum efficiency-luminance characteristics of light-emitting device 2, comparative light-emitting device 2-1, and comparative light-emitting device 2-2. [Figure 41] Figure 41 shows the emission spectra of light-emitting device 2, comparative light-emitting device 2-1, and comparative light-emitting device 2-2. [Figure 42] Figure 42 shows the change in brightness with respect to the operating time of light-emitting device 2, comparative light-emitting device 2-1, and comparative light-emitting device 2-2. [Modes for carrying out the invention]

[0043] The embodiments of the present invention will be described in detail below with reference to the drawings. However, it will be readily apparent to those skilled in the art that the present invention is not limited to the following description, and that its form and details can be modified in various ways without departing from the spirit and scope of the present invention. Accordingly, the present invention shall not be interpreted as being limited to the contents of the embodiments shown below.

[0044] (Embodiment 1) Among organic compounds with carrier transport properties that can be used in organic EL devices, di-[4-(N,N-ditril-amino)-phenyl]cyclohexane (abbreviated as TAPC) is known as one of the materials with a low refractive index. By using a material with a low refractive index in the EL layer, it is possible to obtain a light-emitting device that exhibits high external quantum efficiency. Therefore, by using TAPC, it is possible to obtain a light-emitting device with good external quantum efficiency.

[0045] However, there is usually a trade-off between high carrier transport and low refractive index. This is because carrier transport in organic compounds largely depends on the presence of unsaturated bonds, and organic compounds with many unsaturated bonds tend to have high refractive indices. TAPC is a substance that achieves an exquisite balance between hole transport and low refractive index. On the other hand, compounds like TAPC, which have a 1,1-disubstituted structure of cyclohexane, have a problem in terms of reliability because the insertion of two bulky substituents on one carbon of cyclohexane results in large steric repulsion, inducing instability in the molecule itself. Furthermore, due to the structure of its skeleton consisting of cyclohexane and a simple benzene ring, TAPC has a low glass transition temperature (Tg) and suffers from problems with heat resistance.

[0046] One method for obtaining a highly heat-resistant and reliable hole transport material is to introduce unsaturated hydrocarbon groups, particularly cyclic unsaturated hydrocarbon groups, into the molecule. On the other hand, to obtain a material with a low refractive index, it is preferable to introduce substituents that can lower the refractive index of the molecule. Examples of such substituents include saturated hydrocarbon groups and cyclic saturated hydrocarbon groups.

[0047] Furthermore, materials used as carrier transport materials in organic EL devices preferably have a skeleton with high carrier transport properties, and among these, aromatic amine skeletons are preferred due to their high hole transport properties. To further improve hole transport properties, it is also possible to introduce two amine skeletons. However, as with the TAPC mentioned above, depending on the environment of the substituents arranged around it, the diamine structure may have an unfavorable effect on reliability.

[0048] Overcoming trade-offs, the inventors have discovered a triarylamine compound having a fluorenyl group with an alkyl group at the 9-position and an aryl group with a branched or cyclic alkyl group as a substituent, as an organic compound that combines carrier transportability, carrier implantationability, low refractive index, high heat resistance, and high reliability. This triarylamine compound is a material that has good carrier transportability, carrier implantationability, and reliability comparable to conventional hole transport layer materials with normal refractive indices. Furthermore, by devising the number and substitution positions of alkyl groups in the triarylamine compound, it is possible to create a material with even better properties.

[0049] Furthermore, triarylamine compounds tend to exhibit high hole transport properties when they contain a fluorenyl group. Light-emitting devices using such triarylamine compounds as hole transport layer materials can be made into light-emitting devices with good driving voltage. In addition, the direct bonding of the fluorenyl group to the nitrogen atom of the amine contributes to shallowing the HOMO (Highest Occupied Molecular Orbital) level of the molecule, which is preferable because it facilitates hole transfer.

[0050] Generally, introducing a linear alkyl group into a compound tends to lower the Tg, melting point, or both of the compound compared to introducing a corresponding branched or cyclic alkyl group (for example, one with the same number of carbon atoms). A lower Tg can reduce the heat resistance of the organic EL material. Since EL devices using organic EL materials are desirable to exhibit stable physical properties under various environments in human life, a high Tg is preferable for materials exhibiting equivalent properties. One embodiment of the present invention, a triarylamine compound, has at least one aryl group having a branched or cyclic alkyl group, and by introducing a phenyl group having an alkyl group at the 9th position of the fluorenyl group, it is possible to maintain a high Tg and produce a material with very high heat resistance compared to introducing a linear alkyl group or having only an alkyl group at the 9th position of the fluorenyl group.

[0051] In other words, one aspect of the present invention is an organic compound represented by general formula (G1).

[0052] [ka]

[0053] In the above general formula (G1), Ar 12 represents an aryl group having 6 to 10 carbon atoms forming a ring, and having at least one branched or cyclic alkyl group having 3 to 12 carbon atoms. 12 The total number of carbon atoms in the branched or cyclic alkyl groups having 3 to 12 carbon atoms is 6 to 36. Also, Ar 11 represents an arylene group with 6 to 13 carbon atoms forming a substituted or unsubstituted ring. Also, n represents an integer of 0 or 1. Also, Ar 22 represents an aryl group with 6 to 10 carbon atoms forming a substituted or unsubstituted ring. Also, Ar 21 represents an arylene group with 6 to 13 carbon atoms forming a substituted or unsubstituted ring. m represents an integer of 0 or 1. Also, Ar 1represents a phenyl group having at least one alkyl group with 1 to 6 carbon atoms. Also, Ar 2 R represents a phenyl group having at least one alkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 4 carbon atoms. 1 ~R 4 Each of these independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Also, R 5 ~R 8 One of these bonds directly attaches to a nitrogen atom, while the others each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

[0054] Also, Ar 12 and Ar 22 Examples of aryl groups with 6 to 10 carbon atoms forming a ring that can be used include phenyl groups and naphthyl groups, with phenyl groups being particularly preferred because they allow for a lower refractive index.

[0055] Also, Ar 11 and Ar 21 Examples of arylene groups having 6 to 13 carbon atoms forming a ring that can be used include phenylene groups, naphthylene groups, and fluoroorangeyl groups, with phenyl groups being particularly preferred. When an arylene group having 6 to 13 carbon atoms forming a ring has substituents, the substituents are alkyl groups having 1 to 4 carbon atoms.

[0056] Also, Ar 12Specific examples of branched alkyl groups having 3 to 12 carbon atoms include isopropyl group, isobutyl group, sec-butyl group, tert-butyl group, isopentyl group, sec-pentyl group, tert-pentyl group, neo-pentyl group, isohexyl group, sec-hexyl group, tert-hexyl group, isoheptyl group, sec-heptyl group, tert-heptyl group, neo-heptyl group, isooctyl group, sec-octyl group, tert-octyl group, neo-octyl group, isononyl group, sec-nonyl group, tert-nonyl group, neo-nonyl group, isodecyl group, sec-decyl group, tert-decyl group, isoundecyl group, sec-undecyl group, tert-undecyl group, isododecyl group, sec-dodecyl group, tert-dodecyl group, and the like, with tert-butyl group being particularly preferred.

[0057] Also, Ar 12 Specifically, as the cyclic alkyl group having 3 to 12 carbon atoms, the following can be used: cyclopropyl group, methylcyclopropyl group, cyclobutyl group, methylcyclobutyl group, cyclopentyl group, methylcyclopentyl group, isopropylcyclopentyl group, tert-butylcyclopropyl group, cyclohexyl group, methylcyclohexyl group, isopropylcyclohexyl group, tert-butylcyclohexyl group, cycloheptyl group, methylcycloheptyl group, isopropylcycloheptyl group, tert-butylcycloheptyl group, cyclooctyl group, methylcyclooctyl group, isopropylcyclohexyl group, tert-butylcyclooctyl group, cyclononyl group, methylcyclononyl group, isopropylcyclononyl group, cyclodecyl group, methylcyclodecyl group, cycloundecyl group, methylcycloundecyl group, cyclododecyl group, etc. However, cycloalkyl groups having 6 or more carbon atoms are preferred for lowering the refractive index, and the cyclohexyl group is particularly preferred.

[0058] Also, Ar 1As the C1 to C6 alkyl group, linear, branched, or cyclic alkyl groups having C1 to C6 can be used. Specifically, examples include methyl group, ethyl group, n-propyl group, isopropyl group, cyclopropyl group, n-butyl group, isobutyl group, sec-butyl group, tert-butyl group, cyclobutyl group, methylcyclobutyl group, n-pentyl group, isopentyl group, sec-pentyl group, tert-pentyl group, neo-pentyl group, cyclopentyl group, methylcyclopentyl group, n-hexyl group, isohexyl group, sec-hexyl group, tert-hexyl group, or cyclohexyl group, with tert-butyl group being particularly preferred.

[0059] In this specification, the term "alkyl group" may refer to linear, branched, or cyclic alkyl groups.

[0060] Also, Ar 2 If the alkyl group has at least one C1 to C6 alkyl group, then the C1 to C6 alkyl group is Ar 1 The above-mentioned groups can be used as specific examples of alkyl groups having 1 to 6 carbon atoms.

[0061] Note that Ar 1 and Ar 2 It is preferable that both of them are phenyl groups having at least one alkyl group with 1 to 6 carbon atoms, as this greatly improves the Tg and thus enhances heat resistance.

[0062] Furthermore, one aspect of the present invention is an organic compound represented by the general formula (G2).

[0063] [ka]

[0064] In the above general formula (G2), Ar 1 This represents a phenyl group having at least one alkyl group with 1 to 6 carbon atoms. Also, Ar 2represents a phenyl group having at least one alkyl group with 1 to 6 carbon atoms or an alkyl group with 1 to 4 carbon atoms. Also, R 1 to R 4 each independently represent a hydrogen atom or an alkyl group with 1 to 4 carbon atoms. Also, any one of R 5 to R 8 is a bond directly bonded to the nitrogen atom, and the others each independently represent a hydrogen atom or an alkyl group with 1 to 4 carbon atoms. Also, R 10 to R 14 and R 20 to R 24 each independently represent a hydrogen atom or a branched or cyclic alkyl group with 3 to 12 carbon atoms. However, the total number of carbon atoms of R 10 to R 14 is 6 to 36. Also, n and m each independently represent an integer of 0 or 1.

[0065] Also, as the alkyl group with 1 to 6 carbon atoms that Ar 1 has, a linear, branched or cyclic alkyl group with 1 to 6 carbon atoms can be used. Specifically, a methyl group, an ethyl group, an n-propyl group, an isopropyl group, a cyclopropyl group, an n-butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a cyclobutyl group, a methylcyclobutyl group, an n-pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentyl group, a neo-pentyl group, a cyclopentyl group, a methylcyclopentyl group, an n-hexyl group, an isohexyl group, a sec-hexyl group, a tert-hexyl group, or a cyclohexyl group can be mentioned. Particularly preferably, it is a tert-butyl group.

[0066] In the present specification etc., even when simply described as an alkyl group, it may represent a linear, branched or cyclic alkyl group.

[0067] Also, when Ar 2 is a phenyl group having at least one alkyl group with 1 to 6 carbon atoms, as the alkyl group with 1 to 6 carbon atoms, Ar 1The above-mentioned groups can be used as specific examples of alkyl groups having 1 to 6 carbon atoms.

[0068] Note that Ar 1 and Ar 2 It is preferable that both of them are phenyl groups having at least one alkyl group with 1 to 6 carbon atoms, as this greatly improves the Tg and thus enhances heat resistance.

[0069] Also, R 10 ~R 14 and R 20 ~R 24 Specific examples of branched alkyl groups having 3 to 12 carbon atoms that can be used include isopropyl group, isobutyl group, sec-butyl group, tert-butyl group, isopentyl group, sec-pentyl group, tert-pentyl group, neo-pentyl group, isohexyl group, sec-hexyl group, tert-hexyl group, isoheptyl group, sec-heptyl group, tert-heptyl group, neo-heptyl group, isooctyl group, sec-octyl group, tert-octyl group, neo-octyl group, isononyl group, sec-nonyl group, tert-nonyl group, neo-nonyl group, isodecyl group, sec-decyl group, tert-decyl group, isoundecyl group, sec-undecyl group, tert-undecyl group, isododecyl group, sec-dodecyl group, tert-dodecyl group, etc., with tert-butyl group being particularly preferred.

[0070] Also, R 10 ~R 14 and R 20 ~R 24Specific examples of cyclic alkyl groups having 3 to 12 carbon atoms that can be used include cyclopropyl group, methylcyclopropyl group, cyclobutyl group, methylcyclobutyl group, cyclopentyl group, methylcyclopentyl group, isopropylcyclopentyl group, tert-butylcyclopropyl group, cyclohexyl group, methylcyclohexyl group, isopropylcyclohexyl group, tert-butylcyclohexyl group, cycloheptyl group, methylcycloheptyl group, isopropylcycloheptyl group, tert-butylcycloheptyl group, cyclooctyl group, methylcyclooctyl group, isopropylcyclohexyl group, tert-butylcyclooctyl group, cyclononyl group, methylcyclononyl group, isopropylcyclononyl group, cyclodecyl group, methylcyclodecyl group, cycloundecyl group, methylcycloundecyl group, and cyclododecyl group. However, cycloalkyl groups having 6 or more carbon atoms are preferred for lowering the refractive index, and cyclohexyl groups are particularly preferred.

[0071] Furthermore, one aspect of the present invention is an organic compound represented by the general formula (G3).

[0072] [ka]

[0073] In the above general formula (G3), Ar 1 This represents a phenyl group having at least one branched or cyclic alkyl group having 3 to 6 carbon atoms. Also, Ar 2 R represents a phenyl group having at least one branched or cyclic alkyl group having 3 to 6 carbon atoms, or an alkyl group having 1 to 4 carbon atoms. 1 ~R 4 Each of these independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Also, R 5 ~R 8 One of these is a bond that directly attaches to the nitrogen atom, and the others each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Also, R 10 ~R 14 and R 20 ~R24 Each of these independently represents a hydrogen atom or a branched or cyclic alkyl group having 3 to 12 carbon atoms. However, R 10 ~R 14 The total number of carbon atoms is between 6 and 36. Also, m represents an integer of 0 or 1.

[0074] Also, Ar 1 Specific examples of branched or cyclic alkyl groups having 3 to 6 carbon atoms include isopropyl group, cyclopropyl group, isobutyl group, sec-butyl group, tert-butyl group, cyclobutyl group, methylcyclobutyl group, isopentyl group, sec-pentyl group, tert-pentyl group, neo-pentyl group, cyclopentyl group, methylcyclopentyl group, isohexyl group, sec-hexyl group, tert-hexyl group, or cyclohexyl group, with tert-butyl group being particularly preferred.

[0075] Also, Ar 2 If is a phenyl group having at least one branched or cyclic alkyl group having 3 to 6 carbon atoms, then the branched or cyclic alkyl group having 3 to 6 carbon atoms is Ar 1 The above-mentioned groups can be used as specific examples of branched or cyclic alkyl groups having 3 to 6 carbon atoms.

[0076] Note that Ar 1 and Ar 2 It is preferable that both of them are phenyl groups having at least one branched or cyclic alkyl group having 3 to 6 carbon atoms, as this can further enhance heat resistance.

[0077] Also, R 10 ~R 14 and R 20 ~R 24Specific examples of branched alkyl groups having 3 to 12 carbon atoms that can be used include isopropyl group, isobutyl group, sec-butyl group, tert-butyl group, isopentyl group, sec-pentyl group, tert-pentyl group, neo-pentyl group, isohexyl group, sec-hexyl group, tert-hexyl group, isoheptyl group, sec-heptyl group, tert-heptyl group, neo-heptyl group, isooctyl group, sec-octyl group, tert-octyl group, neo-octyl group, isononyl group, sec-nonyl group, tert-nonyl group, neo-nonyl group, isodecyl group, sec-decyl group, tert-decyl group, isoundecyl group, sec-undecyl group, tert-undecyl group, isododecyl group, sec-dodecyl group, tert-dodecyl group, etc., with tert-butyl group being particularly preferred.

[0078] Also, R 10 ~R 14 and R 20 ~R 24 Specific examples of cyclic alkyl groups having 3 to 12 carbon atoms that can be used include cyclopropyl group, methylisopropyl group, cyclobutyl group, methylcyclobutyl group, cyclopentyl group, methylcyclopentyl group, isopropylcyclopentyl group, tert-butylcyclopropyl group, cyclohexyl group, methylcyclohexyl group, isopropylcyclohexyl group, tert-butylcyclohexyl group, cycloheptyl group, methylcycloheptyl group, isopropylcycloheptyl group, tert-butylcycloheptyl group, cyclooctyl group, methylcyclooctyl group, isopropylcyclohexyl group, tert-butylcyclooctyl group, cyclononyl group, methylcyclononyl group, isopropylcyclononyl group, cyclodecyl group, methylcyclodecyl group, cycloundecyl group, methylcycloundecyl group, and cyclododecyl group. However, cycloalkyl groups having 6 or more carbon atoms are preferred for lowering the refractive index, and cyclohexyl groups are particularly preferred.

[0079] Furthermore, one aspect of the present invention is an organic compound represented by general formula (G4).

[0080] [ka]

[0081] In the above general formula (G4), R 1 ~R 4 Each of these independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Also, R 5 ~R 8 One of these is a bond that directly attaches to the nitrogen atom, and the others each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Also, R 10 ~R 14 and R 20 ~R 24 Each of these independently represents a hydrogen atom or a branched or cyclic alkyl group having 3 to 12 carbon atoms. However, R 10 ~R 14 The total number of carbon atoms is between 6 and 36. Also, R 30 ~R 34 At least one of these represents a branched or cyclic alkyl group having 3 to 6 carbon atoms, and the others represent hydrogen atoms. Also, R 40 ~R 44 At least one of these represents a branched or cyclic alkyl group having 3 to 6 carbon atoms, and the others represent hydrogen atoms. Also, m represents an integer of 0 or 1.

[0082] Also, R 10 ~R 14 and R 20 ~R 24Specific examples of branched alkyl groups having 3 to 12 carbon atoms that can be used include isopropyl group, isobutyl group, sec-butyl group, tert-butyl group, isopentyl group, sec-pentyl group, tert-pentyl group, neo-pentyl group, isohexyl group, sec-hexyl group, tert-hexyl group, isoheptyl group, sec-heptyl group, tert-heptyl group, neo-heptyl group, isooctyl group, sec-octyl group, tert-octyl group, neo-octyl group, isononyl group, sec-nonyl group, tert-nonyl group, neo-nonyl group, isodecyl group, sec-decyl group, tert-decyl group, isoundecyl group, sec-undecyl group, tert-undecyl group, isododecyl group, sec-dodecyl group, tert-dodecyl group, etc., with tert-butyl group being particularly preferred.

[0083] Also, R 10 ~R 14 and R 20 ~R 24 Specific examples of cyclic alkyl groups having 3 to 12 carbon atoms that can be used include cyclopropyl group, methylisopropyl group, cyclobutyl group, methylcyclobutyl group, cyclopentyl group, methylcyclopentyl group, isopropylcyclopentyl group, tert-butylcyclopropyl group, cyclohexyl group, methylcyclohexyl group, isopropylcyclohexyl group, tert-butylcyclohexyl group, cycloheptyl group, methylcycloheptyl group, isopropylcycloheptyl group, tert-butylcycloheptyl group, cyclooctyl group, methylcyclooctyl group, isopropylcyclohexyl group, tert-butylcyclooctyl group, cyclononyl group, methylcyclononyl group, isopropylcyclononyl group, cyclodecyl group, methylcyclodecyl group, cycloundecyl group, methylcycloundecyl group, and cyclododecyl group. However, cycloalkyl groups having 6 or more carbon atoms are preferred for lowering the refractive index, and cyclohexyl groups are particularly preferred.

[0084] Also, R 30 ~R 34 and R 40 ~R44 Specific examples of branched or cyclic alkyl groups having 3 to 6 carbon atoms that can be used include isopropyl group, cyclopropyl group, isobutyl group, sec-butyl group, tert-butyl group, cyclobutyl group, methylcyclobutyl group, isopentyl group, sec-pentyl group, tert-pentyl group, neo-pentyl group, cyclopentyl group, methylcyclopentyl group, isohexyl group, sec-hexyl group, tert-hexyl group, or cyclohexyl group, with tert-butyl group being particularly preferred.

[0085] Furthermore, in one aspect of the present invention, in the above general formulas (G1) to (G4), R 1 ~R 4 R is a hydrogen atom, 5 ~R 8 It is an organic compound in which one of the bonds is directly bonded to a nitrogen atom, and the other is a hydrogen atom.

[0086] Furthermore, in one aspect of the present invention, in the above general formulas (G1) to (G4), R 10 ~R 14 The organic compound is one in which at least one of the groups is a tert-butyl group or a cyclohexyl group.

[0087] Furthermore, in one aspect of the present invention, in the above general formulas (G1) to (G4), R 10 , R 12 , and R 14 is a hydrogen atom, and R 11 and R 13 It is an organic compound in which the group is either a tert-butyl group or a cyclohexyl group.

[0088] Furthermore, in one aspect of the present invention, in the above general formulas (G1) to (G4), R 10 , R 11 , R 13 , and R 14 is a hydrogen atom, and R 12 It is an organic compound in which the group is either a tert-butyl group or a cyclohexyl group.

[0089] Furthermore, in one aspect of the present invention, in the above general formulas (G1) to (G4), it is possible to use compounds with very low refractive indices, such that the paraphotorefractive index of the layer made of the organic compound is 1.50 or more and 1.75 or less for light with a wavelength of 465 nm, 1.50 or more and 1.70 or less for light with a wavelength of 520 nm, and 1.45 or more and 1.70 or less for light with a wavelength of 633 nm (numerical range for refractive index).

[0090] Furthermore, if anisotropy is present in the material, the refractive index for ordinary light and the refractive index for extraordinary light may differ. If the thin film to be measured is in such a state, anisotropy analysis can be performed to separate the refractive index for ordinary light and the refractive index for extraordinary light and calculate the refractive index of each. In this specification, if both ordinary and extraordinary refractive indices are present in the measured material, the ordinary refractive index is used as the index.

[0091] An organic compound according to one embodiment of the present invention having the above-described configuration is an organic compound with good hole transport properties and a low refractive index, and therefore can be suitably used as a material for the hole transport layer or hole injection layer of an organic EL device. Furthermore, an organic EL device using this hole transport layer material or hole injection layer material has a hole transport layer or hole injection layer with a low refractive index, and can therefore be a light-emitting device with high luminous efficiency, i.e., external quantum efficiency, current efficiency, and blue index.

[0092] Furthermore, an organic compound according to one embodiment of the present invention having the above configuration is an organic compound with a relatively shallow HOMO level. Normally, the HOMO levels of the materials constituting adjacent layers such as the hole injection layer and the hole transport layer are close to the HOMO levels of the materials constituting the light-emitting layer, and by becoming shallow within an appropriate range, the hole acceptance from these layers to the light-emitting layer is improved. On the other hand, if a material with a shallow HOMO level is used as the material constituting the hole transport layer in contact with the light-emitting layer of an organic EL device, a low-energy exciplex may be formed between the HOMO level of the material constituting the hole transport layer and the LUMO (Lowest Unoccupied Molecular Orbital) level of the material constituting the light-emitting layer, which may reduce the luminous efficiency.

[0093] However, one embodiment of the present invention is an organic compound having a bulky alkyl group. Therefore, when used as a hole transport layer material in contact with the light-emitting layer of an organic EL device, the steric effect of the bulky alkyl group reduces the interaction between the material constituting the adjacent light-emitting layer and the hole transport layer material compared to a normal organic EL device. This suppresses the formation of an excyplex between the HOMO level of the material constituting the hole transport layer and the LUMO level of the material constituting the light-emitting layer, thus preventing a decrease in luminous efficiency caused by excyplex formation. Accordingly, by using the organic compound of one embodiment of the present invention, it becomes possible to manufacture an organic EL device with a low driving voltage and high efficiency.

[0094] The HOMO level of the organic compound in one aspect of the present invention is preferably -5.30 eV or less and -5.50 eV or more, and particularly preferably -5.30 eV or less and -5.40 eV or more (numerical range for HOMO level). As a result, the organic compound in one aspect of the present invention can be suitably used as a hole transport layer material in contact with the light-emitting layer of an organic EL device.

[0095] Furthermore, an organic compound according to one embodiment of the present invention having the above-described configuration can be a compound with a large giant surface potential (GSP) of 20 mV / nm or more (numerical range for GSP).

[0096] Giant surface potential refers to the phenomenon where the surface potential of a deposited film increases in proportion to its film thickness. To treat its magnitude as a value independent of film thickness, one can use the value obtained by dividing the surface potential of the deposited film by its film thickness, i.e., the potential gradient (slope) of the surface potential of the deposited film. In this specification, this potential gradient of the surface potential of the deposited film is referred to as GSP (mV / nm).

[0097] In an organic semiconductor device having at least two layers stacked in contact with each other (a first hole transport layer and a second hole transport layer), if holes flow from the first hole transport layer to the second hole transport layer, and the difference ΔGSP(GSP2-GSP1) between the GSP(GSP1) of the organic compound constituting the first hole transport layer and the GSP(GSP2) of the organic compound constituting the second hole transport layer is positive, then hole injection is easy, and it becomes possible to create an organic semiconductor device with a low driving voltage. Therefore, in such a case, the organic compound according to one embodiment of the present invention can be suitably used as the first hole transport layer.

[0098] Furthermore, an organic compound according to one aspect of the present invention preferably satisfies at least two of the numerical ranges for refractive index, HOMO level, and GSP mentioned above, and more preferably satisfies three.

[0099] Next, specific examples of organic compounds having the above-described configurations, which represent one aspect of the present invention, are shown below.

[0100] [ka]

[0101] [ka]

[0102]

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[0103]

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[0104]

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[0105]

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[0106]

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[0107]

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[0108]

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[0109]

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[0110]

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[0111]

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[0112] [ka]

[0113] [ka]

[0114] [ka]

[0115] [ka]

[0116] [ka]

[0117] [ka]

[0118] [ka]

[0119] [ka]

[0120] The organic compounds represented by the above structural formulas (100) to (181) and (200) to (281) are examples of organic compounds represented by the above general formulas (G1) to (G4), but the organic compounds in one aspect of the present invention are not limited thereto.

[0121] Next, an embodiment of the present invention, a method for synthesizing an organic compound represented by the following general formula (G1), will be described.

[0122] [ka]

[0123] In the above general formula (G1), Ar 12 represents an aryl group having 6 to 10 carbon atoms forming a ring, and having at least one branched or cyclic alkyl group having 3 to 12 carbon atoms. 12 The sum of the number of carbon atoms in the branched or cyclic alkyl groups having 3 to 12 carbon atoms is 6 to 36. Also, Ar 11 represents an arylene group with 6 to 13 carbon atoms forming a substituted or unsubstituted ring. Also, n represents an integer of 0 or 1. Also, Ar 22 represents an aryl group with 6 to 10 carbon atoms forming a substituted or unsubstituted ring. Also, Ar 21 represents an arylene group with 6 to 13 carbon atoms forming a substituted or unsubstituted ring. m represents an integer of 0 or 1. Also, Ar 1 represents a phenyl group having at least one alkyl group with 1 to 6 carbon atoms. Also, Ar 2 R represents a phenyl group having at least one alkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 4 carbon atoms. 1 ~R 4 Each of these independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Also, R 5 ~R 8 One of these bonds directly attaches to a nitrogen atom, while the others each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

[0124] First, as shown in the synthesis scheme (A-1) below, an arylamine and a halide having a fluorene skeleton are coupled with a metal catalyst, metal, or metal compound in the presence of a base to obtain a secondary amine.

[0125] [ka]

[0126] In the above synthesis scheme (A-1), Ar 12 represents an aryl group having 6 to 10 carbon atoms forming a ring, and having at least one branched or cyclic alkyl group having 3 to 12 carbon atoms. 12 The sum of the number of carbon atoms in the branched or cyclic alkyl groups having 3 to 12 carbon atoms is 6 to 36. Also, Ar 11 represents an arylene group with 6 to 13 carbon atoms forming a substituted or unsubstituted ring. Also, n represents an integer of 0 or 1. Also, Ar 1 represents a phenyl group having at least one alkyl group with 1 to 6 carbon atoms. Also, Ar 2 R represents a phenyl group having at least one alkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 4 carbon atoms. 1 ~R 4 Each of these independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Also, R 5 ~R 8 One of these bonds directly attaches to a nitrogen atom, while the others each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

[0127] When the above synthesis scheme (A-1) is carried out using the Buchwald-Hartwig reaction, X represents a halogen or a triflate group. Preferred halogens are iodine, bromine, or chlorine. This reaction can utilize a palladium catalyst using a palladium complex or compound such as bis(dibenzylideneacetone)palladium(O) or allyl palladium chloride dimer(II), and a ligand such as tri(tert-butyl)phosphine, di-tert-butyl(1-methyl-2,2-diphenylcyclopropyl)phosphine, or tricyclohexylphosphine. Specific examples of bases include organic bases such as sodium tert-butoxide, or inorganic bases such as potassium carbonate. When using a solvent, toluene, xylene, 1,3,5-trimethylbenzene, etc., can be used.

[0128] When the above synthetic scheme (A-1) is carried out using the Ullmann reaction, X represents a halogen. As the halogen, iodine, bromine, or chlorine is preferred. As the catalyst, copper or a copper compound can be used. In particular, it is preferable to use copper(I) iodide or copper(II) acetate. Examples of the base to be used include inorganic bases such as potassium carbonate. As the solvent, 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)pyrimidinone (DMPU), N-methyl-2-pyrrolidone (NMP), toluene, xylene, 1,3,5-trimethylbenzene, or the like can be used. However, the solvents that can be used are not limited to these. In the Ullmann reaction, since the target product can be obtained in a shorter time and in a higher yield when the reaction temperature is 100°C or higher, it is preferable to use DMPU, NMP, or 1,3,5-trimethylbenzene having a high boiling point. Further, since a higher temperature of 150°C or higher is more preferable for the reaction temperature, it is more preferable to use DMPU.

[0129] Next, by coupling the secondary amine obtained in the above synthetic scheme (A-1) and an aryl halide with a metal catalyst, a metal, or a metal compound in the presence of a base, an organic compound represented by the general formula (G1) can be obtained as shown in the following synthetic scheme (A-2).

[0130]

Chemical formula

[0131] In the above synthetic scheme (A-2), Ar 12 represents an aryl group having 6 to 10 carbon atoms forming a ring and having at least one branched or cyclic alkyl group having 3 to 12 carbon atoms. The total number of carbon atoms of the branched or cyclic alkyl group having 3 to 12 carbon atoms possessed by Ar 12 is 6 to 36. Also, Ar 11 represents an arylene group having 6 to 13 carbon atoms forming a substituted or unsubstituted ring. Also, n represents an integer of 0 or 1. Also, Ar 22represents an aryl group having 6 to 10 carbon atoms forming a substituted or unsubstituted ring. Also, Ar 21 represents an arylene group having 6 to 13 carbon atoms forming a substituted or unsubstituted ring. Also, m represents an integer of 0 or 1. Also, Ar 1 represents a phenyl group having at least one alkyl group with 1 to 6 carbon atoms. Also, Ar 2 represents a phenyl group having at least one alkyl group with 1 to 6 carbon atoms, or an alkyl group with 1 to 4 carbon atoms. Also, R 1 to R 4 each independently represents a hydrogen atom or an alkyl group with 1 to 4 carbon atoms. Also, R 5 to R 8 any one of them is a bond directly bonded to a nitrogen atom, and the others each independently represent a hydrogen atom or an alkyl group with 1 to 4 carbon atoms.

[0132] When the above synthesis scheme (A-2) is carried out using the backward Hartwig reaction, X represents a halogen or a triflate group. As the halogen, iodine, bromine, or chlorine is preferable. In this reaction, a palladium catalyst using a palladium complex or compound such as bis(dibenzylideneacetone)palladium(0) or allyl palladium chloride dimer(II) and a ligand such as tri(tert-butyl)phosphine, di-tert-butyl(1-methyl-2,2-diphenylcyclopropyl)phosphine, or tricyclohexylphosphine coordinated thereto can be used. Specific examples of the base include organic bases such as sodium tert-butoxide and inorganic bases such as potassium carbonate. Also, when using a solvent, toluene, xylene, 1,3,5-trimethylbenzene, etc. can be used.

[0133] Furthermore, when the above synthesis scheme (A-2) is carried out using the Ullmann reaction, X represents a halogen. Preferred halogens are iodine, bromine, or chlorine. Copper or copper compounds can be used as catalysts. It is preferable to use copper(I) iodide or copper(II) acetate. Examples of bases used include inorganic bases such as potassium carbonate. The solvents used are 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)pyrimidinone (DMPU), N-methyl-2-pyrrolidone (NMP), toluene, xylene, or 1,3,5-trimethylbenzene. However, the solvents that can be used are not limited to these. In the Ullmann reaction, the target product can be obtained in a shorter time and in higher yield if the reaction temperature is 100°C or higher, so it is preferable to use DMPU, NMP, or 1,3,5-trimethylbenzene, which have high boiling points. Furthermore, a reaction temperature of 150°C or higher is even more preferable, so it is even more preferable to use DMPU.

[0134] The reaction order in the above synthesis schemes (A-1) and (A-2) is not limited thereto. In some cases, the organic compound represented by general formula (G1) can also be obtained by reacting a secondary amine, obtained by reacting an aryl halide with an arylamine, with a halide having a fluorene skeleton.

[0135] Furthermore, the fluorene-containing halides used in the above synthesis scheme (A-1) can also be synthesized by the methods shown in the following synthesis schemes (A-3) and (A-4). First, as shown in synthesis scheme (A-3), a halide biphenyl is reacted with a bis(alkylaryl) ketone or an alkyl(alkylaryl) ketone.

[0136] [ka]

[0137] In the above synthesis scheme (A-3), Ar 1represents a phenyl group having at least one alkyl group with 1 to 6 carbon atoms. Also, Ar 2 R represents a phenyl group having at least one alkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 4 carbon atoms. 1 ~R 4 Each of these independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Also, R 5 ~R 8 One of the bonds is attached to a halogen atom, and the others each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. X and Z also represent halogens. Bromine or chlorine is preferred for X. Iodine or bromine is preferred for Z. When X is bromine, iodine is more preferred for Z from the viewpoint of reaction site selectivity.

[0138] In the above synthesis scheme (A-3), the target biphenyl derivative can be lithiated and reacted with a ketone by using an n-butyllithium hexane solution, metallic lithium, etc., as the lithiation reagent. Metals such as magnesium can be used in the same way.

[0139] Next, as shown in synthesis scheme (A-4), a halide having a fluorene skeleton can be synthesized by cyclizing the compound obtained in synthesis scheme (A-3).

[0140] [ka]

[0141] In the above synthesis scheme (A-4), Ar 1 represents a phenyl group having at least one alkyl group with 1 to 6 carbon atoms. Also, Ar 2 R represents a phenyl group having at least one alkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 4 carbon atoms. 1 ~R 4 Each of these independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Also, R 5 ~R 8One of the bonds is a bond to a halogen atom, and the others each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. Also, X represents a halogen. Bromine or chlorine is preferred as X.

[0142] In the above synthesis scheme (A-4), Brønsted acids, Lewis acids, etc., can be used. When a ketone having an alkyl group adjacent to the carbonyl group is used as the ketone, it is preferable to use a Lewis acid from the viewpoint of reaction selectivity.

[0143] Furthermore, since various types of halogenated biphenyls, bis(alkylaryl) ketones, or alkyl(alkylaryl) ketones used in the above synthesis scheme are commercially available or can be easily synthesized using known techniques, a large number of organic compounds represented by general formula (G1) can be synthesized. Therefore, the organic compounds according to one embodiment of the present invention offer a wide variety of options.

[0144] The above describes an example of a method for synthesizing an organic compound, which is one aspect of the present invention. However, the present invention is not limited thereto, and the compound may be synthesized by any other method.

[0145] The configuration shown in this embodiment can be used in appropriate combination with the configurations shown in other embodiments.

[0146] (Embodiment 2) In this embodiment, the light-emitting device using the organic compound shown in Embodiment 1 will be described with reference to Figures 1(A) to 1(E).

[0147] ≪Basic Structure of Light-Emitting Devices≫ The basic structure of a light-emitting device will be described. Figure 1(A) shows a light-emitting device having an EL layer containing a light-emitting layer between a pair of electrodes. Specifically, it has a structure in which an EL layer 103 is sandwiched between a first electrode 101 and a second electrode 102.

[0148] Further, FIG. 1(B) shows a light-emitting device having a stacked structure (tandem structure) with a plurality of (two layers in FIG. 1(B)) EL layers (103a, 103b) between a pair of electrodes and having a charge generation layer 106 between the EL layers. The light-emitting device with a tandem structure can realize a light-emitting device that can be driven at a low voltage and has low power consumption.

[0149] When a potential difference is generated between the first electrode 101 and the second electrode 102, the charge generation layer 106 has a function of injecting electrons into one EL layer (103a or 103b) and injecting holes into the other EL layer (103b or 103a). Therefore, in FIG. 1(B), when a voltage is applied to the first electrode 101 such that the potential becomes higher than that of the second electrode 102, electrons are injected from the charge generation layer 106 into the EL layer 103a, and holes are injected into the EL layer 103b.

[0150] Note that the charge generation layer 106 preferably has translucency with respect to visible light (specifically, the transmittance of visible light with respect to the charge generation layer 106 is 40% or more) from the viewpoint of light extraction efficiency. Further, the charge generation layer 106 functions even if it has a lower conductivity than the first electrode 101 and the second electrode 102.

[0151] Figure 1(C) shows the laminated structure of the EL layer 103 of a light-emitting device according to one embodiment of the present invention. In this case, the first electrode 101 functions as an anode and the second electrode 102 functions as a cathode. The EL layer 103 has a structure in which a hole injection layer 111, a hole transport layer 112, a light-emitting layer 113, an electron transport layer 114, and an electron injection layer 115 are sequentially laminated on the first electrode 101. The light-emitting layer 113 may be a configuration in which multiple light-emitting layers of different emission colors are laminated. For example, a light-emitting layer containing a red light-emitting material, a light-emitting layer containing a green light-emitting material, and a light-emitting layer containing a blue light-emitting material may be laminated, or laminated via a layer having a carrier transport material. Alternatively, a combination of a light-emitting layer containing a yellow light-emitting material and a light-emitting layer containing a blue light-emitting material may be used. However, the laminated structure of the light-emitting layer 113 is not limited to the above. For example, the light-emitting layer 113 may be a structure in which multiple light-emitting layers of the same emission color are stacked. For example, a first light-emitting layer containing a blue light-emitting material and a second light-emitting layer containing a blue light-emitting material may be stacked, or a structure in which they are stacked via a layer having a carrier transport material. In the case of a structure in which multiple light-emitting layers of the same emission color are stacked, reliability can be increased compared to a single-layer structure. Also, even when there are multiple EL layers as in the tandem structure shown in Figure 1(B), each EL layer is stacked sequentially from the anode side as described above. Furthermore, if the first electrode 101 is the cathode and the second electrode 102 is the anode, the stacking order of the EL layer 103 is reversed. Specifically, on the first electrode 101, which is the cathode, 111 is an electron injection layer, 112 is an electron transport layer, 113 is a light-emitting layer, 114 is a hole transport layer, and 115 is a hole injection layer.

[0152] The light-emitting layers 113 contained in the EL layers (103, 103a, 103b) each contain a combination of light-emitting material and multiple materials as appropriate, and can be configured to produce fluorescence or phosphorescence that exhibits a desired emission color. Alternatively, the light-emitting layers 113 may be arranged in a laminated structure with different emission colors. In this case, the light-emitting material and other materials used in each laminated light-emitting layer may be different materials. Furthermore, a configuration in which different emission colors can be obtained from multiple EL layers (103a, 103b) as shown in Figure 1(B) is also possible. In this case as well, the light-emitting material and other materials used in each light-emitting layer may be different materials.

[0153] Furthermore, in a light-emitting device according to one aspect of the present invention, for example, by using a reflective electrode as the first electrode 101 shown in Figure 1(C) and a semi-transparent / semi-reflective electrode as the second electrode 102, and by using a micro-cavity structure, the light emitted from the light-emitting layer 113 contained in the EL layer 103 can be made to resonate between the two electrodes, thereby strengthening the light emitted from the second electrode 102.

[0154] Furthermore, if the first electrode 101 of the light-emitting device is a reflective electrode consisting of a laminated structure of a reflective conductive material and a translucent conductive material (transparent conductive film), optical adjustment can be performed by controlling the film thickness of the transparent conductive film. Specifically, it is preferable to adjust the optical distance (product of film thickness and refractive index) between the first electrode 101 and the second electrode 102 to be mλ / 2 (where m is a natural number) or close to it, with respect to the wavelength λ of light obtained from the light-emitting layer 113.

[0155] Furthermore, in order to amplify the desired light (wavelength: λ) obtained from the light-emitting layer 113, it is preferable to adjust the optical distance from the first electrode 101 to the region of the light-emitting layer 113 where the desired light is obtained (light-emitting region), and the optical distance from the second electrode 102 to the region of the light-emitting layer 113 where the desired light is obtained (light-emitting region), so that they are (2m'+1)λ / 4 (where m' is a natural number) or close to it. The light-emitting region referred to here is the region in the light-emitting layer 113 where holes and electrons recombine.

[0156] By performing such optical adjustments, the spectrum of specific monochromatic light obtained from the light-emitting layer 113 can be narrowed, resulting in emission with good color purity.

[0157] However, in the above case, the optical distance between the first electrode 101 and the second electrode 102 can be precisely defined as the total thickness from the reflective region of the first electrode 101 to the reflective region of the second electrode 102. However, since it is difficult to precisely determine the reflective regions of the first electrode 101 and the second electrode 102, the above effects can be sufficiently obtained by assuming that any position on the first electrode 101 and the second electrode 102 are reflective regions. Furthermore, the optical distance between the first electrode 101 and the light-emitting layer from which the desired light is obtained can be precisely defined as the optical distance between the reflective region of the first electrode 101 and the light-emitting region of the light-emitting layer from which the desired light is obtained. However, since it is difficult to precisely determine the reflective region of the first electrode 101 and the light-emitting region of the light-emitting layer from which the desired light is obtained, the above effects can be sufficiently obtained by assuming that any position on the first electrode 101 is a reflective region and any position on the light-emitting layer from which the desired light is obtained is a light-emitting region.

[0158] The light-emitting device shown in Figure 1(D) is a light-emitting device having a tandem structure and a microcavity structure, which allows for the extraction of light of different wavelengths (monochromatic light) from each EL layer (103a, 103b). Therefore, color separation (e.g., RGB) to obtain different emission colors is unnecessary. Consequently, high resolution can be easily achieved. It can also be combined with a colored layer (color filter). Furthermore, it is possible to strengthen the emission intensity in the front direction at a specific wavelength, thereby reducing power consumption.

[0159] The light-emitting device shown in Figure 1(E) is an example of a tandem-structured light-emitting device shown in Figure 1(B). As shown in the figure, it has a structure in which three EL layers (103a, 103b, 103c) are stacked with charge generation layers (106a, 106b) in between. Each of the three EL layers (103a, 103b, 103c) has a light-emitting layer (113a, 113b, 113c), and the light-emitting colors of each light-emitting layer can be freely combined. For example, light-emitting layer 113a can be blue, light-emitting layer 113b can be red, green, or yellow, and light-emitting layer 113c can be blue. Alternatively, light-emitting layer 113a can be red, light-emitting layer 113b can be blue, green, or yellow, and light-emitting layer 113c can be red.

[0160] In the light-emitting device according to one aspect of the present invention described above, at least one of the first electrode 101 and the second electrode 102 is a light-transmitting electrode (such as a transparent electrode or a semi-transparent / semi-reflective electrode). If the light-transmitting electrode is a transparent electrode, the transmittance of visible light of the transparent electrode shall be 40% or more. If it is a semi-transparent / semi-reflective electrode, the reflectance of visible light of the semi-transparent / semi-reflective electrode shall be 20% or more and 80% or less, preferably 40% or more and 70% or less. Furthermore, the resistivity of these electrodes shall be 1 × 10⁻⁶. -2 It is preferable to keep it below Ωcm.

[0161] Furthermore, in the light-emitting device according to one aspect of the present invention described above, if one of the first electrode 101 and the second electrode 102 is a reflective electrode (reflective electrode), the visible light reflectance of the reflective electrode is 40% or more and 100% or less, preferably 70% or more and 100% or less. In addition, the resistivity of this electrode is 1 × 10⁻⁶. -2 It is preferable to keep it below Ωcm.

[0162] ≪Specific structure of a light-emitting device≫ Next, a specific structure of a light-emitting device according to one aspect of the present invention will be described. Here, we will use Figure 1(D), which has a tandem structure, for explanation. The same applies to the EL layer configuration for the single-structure light-emitting devices shown in Figures 1(A) and 1(C). Furthermore, if the light-emitting device shown in Figure 1(D) has a microcavity structure, the first electrode 101 is formed as a reflective electrode, and the second electrode 102 is formed as a semi-transparent / semi-reflective electrode. Thus, one or more desired electrode materials can be used and formed in a single layer or in a stacked manner. The second electrode 102 is formed after the EL layer 103b is formed, by selecting a material in the same manner as described above.

[0163] <First electrode and second electrode> As materials for forming the first electrode 101 and the second electrode 102, any combination of the following materials can be used as long as the functions of both electrodes described above are met. For example, metals, alloys, electrically conductive compounds, and mixtures thereof can be used as appropriate. Specifically, these include In-Sn oxide (also called ITO), In-Si-Sn oxide (also called ITSO), In-Zn oxide, and In-W-Zn oxide. In addition, metals such as aluminum (Al), titanium (Ti), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), gallium (Ga), zinc (Zn), indium (In), tin (Sn), molybdenum (Mo), tantalum (Ta), tungsten (W), palladium (Pd), gold (Au), platinum (Pt), silver (Ag), yttrium (Y), neodymium (Nd), and alloys containing these in appropriate combinations can also be used. In addition, elements belonging to Group 1 or Group 2 of the periodic table not exemplified above (for example, lithium (Li), cesium (Cs), calcium (Ca), strontium (Sr)), rare earth metals such as europium (Eu) and ytterbium (Yb), and alloys containing these in appropriate combinations, as well as graphene and other materials can be used.

[0164] In the light-emitting device shown in Figure 1(D), when the first electrode 101 is the anode, the hole injection layer 111a and the hole transport layer 112a of the EL layer 103a are sequentially laminated on the first electrode 101 by vacuum deposition. After the EL layer 103a and the charge generation layer 106 are formed, the hole injection layer 111b and the hole transport layer 112b of the EL layer 103b are similarly sequentially laminated on the charge generation layer 106.

[0165] <Hole injection layer> The hole injection layers (111, 111a, 111b) are layers that inject holes from the first electrode 101, which is the anode, or the charge generation layers (106, 106a, 106b) into the EL layers (103, 103a, 103b), and are layers containing organic acceptor material or a material with high hole injection potential.

[0166] Organic acceptor materials are materials that can generate holes in an organic compound by separating its charge from other organic compounds whose LUMO level and HOMO level are close. Therefore, compounds having electron-withdrawing groups (halogen groups or cyano groups), such as quinodimethane derivatives, chloranil derivatives, and hexaazatriphenylene derivatives, can be used as organic acceptor materials. For example, 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviated as F4-TCNQ), 3,6-difluoro-2,5,7,7,8,8-hexacyanoquinodimethane, chloranil, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexazatriphenylene (abbreviated as HAT-CN), 1,3,4,5,7,8-hexafluorotetracyano-naphthoquinodimethane (abbreviated as F6-TCNNQ), 2-(7-dicyanomethylene-1,3,4,5,6,8,9,10-octafluoro-7H-pyrene-2-ylidene)malononitrile, etc. can be used. Furthermore, among organic acceptor materials, compounds in which an electron-withdrawing group is bonded to a condensed aromatic ring having multiple heteroatoms, such as HAT-CN, are particularly suitable because they have high acceptability and stable film properties with respect to heat. In addition, radialene derivatives having an electron-withdrawing group (especially a halogen group such as a fluoro group or a cyano group) [3] are also preferred because they have very high electron-accepting properties. Specifically, α,α',α''-1,2,3-cyclopropanetriylidenates[4-cyano-2,3,5,6-tetrafluorobenzeneacetonitrile], α,α',α''-1,2,3-cyclopropanetriylidenates[2,6-dichloro-3,5-difluoro-4-(trifluoromethyl)benzeneacetonitrile], and α,α',α''-1,2,3-cyclopropanetriylidenates[2,3,4,5,6-pentafluorobenzeneacetonitrile] can be used.

[0167] Furthermore, as materials with high hole injection potential, oxides of metals belonging to groups 4 through 8 of the periodic table (such as molybdenum oxide, vanadium oxide, ruthenium oxide, tungsten oxide, manganese oxide, and other transition metal oxides) can be used. Specifically, examples include molybdenum oxide, vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, tungsten oxide, manganese oxide, and rhenium oxide. Among these, molybdenum oxide is preferred because it is stable in the atmosphere, has low hygroscopicity, and is easy to handle. In addition, phthalocyanine compounds such as phthalocyanine (abbreviated as H2Pc) and copper phthalocyanine (abbreviated as CuPc) can be used.

[0168] In addition to the above materials, the low molecular weight compounds 4,4',4''-tris(N,N-diphenylamino)triphenylamine (abbreviation: TDATA), 4,4',4''-tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine (abbreviation: MTDATA), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), N,N'-bis{4-[bis(3-methylphenyl)amino]phenyl}-N,N'-diphenyl-(1,1'-biphenyl)-4,4'-diamine (abbreviation: DNTPD), 1,3,5- Aromatic amine compounds such as tris[N-(4-diphenylaminophenyl)-N-phenylamino]benzene (abbreviation: DPA3B), 3-[N-(9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3,6-bis[N-(9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA2), and 3-[N-(1-naphthyl)-N-(9-phenylcarbazole-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1) can be used.

[0169] Furthermore, polymer compounds (oligomers, dendrimers, polymers, etc.) such as poly(N-vinylcarbazole) (abbreviated as PVK), poly(4-vinyltriphenylamine) (abbreviated as PVTPA), poly[N-(4-{N'-[4-(4-diphenylamino)phenyl]phenyl-N'-phenylamino}phenyl)methacrylamide] (abbreviated as PTPDMA), and poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)benzidine] (abbreviated as Poly-TPD) can be used. Alternatively, polymer compounds to which acids such as poly(3,4-ethylenedioxythiophene) / poly(styrenesulfonic acid) (abbreviated as PEDOT / PSS) and polyaniline / poly(styrenesulfonic acid) (PAni / PSS) can be added can also be used.

[0170] Furthermore, as a material with high hole injection capabilities, a mixed material containing a hole transport material and the aforementioned organic acceptor material (electron-accepting material) can also be used. In this case, electrons are extracted from the hole transport material by the organic acceptor material, generating holes in the hole injection layer 111, and these holes are injected into the light-emitting layer 113 via the hole transport layer 112. The hole injection layer 111 may be formed as a single layer of a mixed material containing a hole transport material and an organic acceptor material (electron-accepting material), or it may be formed by laminating the hole transport material and the organic acceptor material (electron-accepting material) in separate layers.

[0171] It is preferable to use the organic compound shown in Embodiment 1 as the hole transport material. Furthermore, as the hole transport material, the hole mobility at which the square root of the electric field strength [V / cm] is 600 is 1 × 10⁻⁶. -6 cm 2 A material having a hole mobility of / Vs or higher is preferred. However, any material that has higher hole transport than electron transport can be used.

[0172] Furthermore, as hole-transporting materials, materials with high hole-transporting properties such as compounds having a π-electron-rich heteroaromatic ring (e.g., carbazole derivatives, furan derivatives, or thiophene derivatives) and aromatic amines (organic compounds having an aromatic amine skeleton) are preferred.

[0173] Examples of the above-mentioned carbazole derivatives (organic compounds having a carbazole ring) include bicarbazole derivatives (for example, 3,3'-bicarbazole derivatives) and aromatic amines having a carbazolyl group.

[0174] Furthermore, specific examples of the above-mentioned bicarbazole derivatives (for example, 3,3'-bicarbazole derivatives) include 3,3'-bis(9-phenyl-9H-carbazole) (abbreviated as PCCP), 9,9'-bis(biphenyl-4-yl)-3,3'-bi-9H-carbazole (abbreviated as BisBPCz), 9,9'-bis(1,1'-biphenyl-3-yl)-3,3'-bi-9H-carbazole (abbreviated as BismBPCz), 9-(1,1'-biphenyl-3-yl)-9'-(1,1'-biphenyl-4-yl)-9H,9'H-3,3'-bicarbazole (abbreviated as mBPCCBP), and 9-(2-naphthyl)-9'-phenyl-9H,9'H-3,3'-bicarbazole (abbreviated as βNCCP).

[0175] Furthermore, examples of aromatic amines having the above-mentioned carbazolyl group include 4-phenyl-4'-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviated as PCBA1BP), N-(4-biphenyl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-9-phenyl-9H-carbazole-3-amine (abbreviated as PCBiF), and N-(1,1'-biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazole-3- [9,9-dimethyl-9H-fluoren-2-amine (abbreviation: PCBBiF), 4,4'-diphenyl-4''-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBBi1BP), 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBANB), 4,4'-di(1-naphthyl)-4''-(9-phenyl-9H-carbazole-3-yl) Diphenylamine (abbreviation: PCBNBB), 4-phenyldiphenyl-(9-phenyl-9H-carbazole-3-yl)amine (abbreviation: PCA1BP), N,N'-bis(9-phenylcarbazole-3-yl)-N,N'-diphenylbenzene-1,3-diamine (abbreviation: PCA2B), N,N',N''-triphenyl-N,N',N''-tris(9-phenylcarbazole-3-yl)benzene-1,3,5-triamine (abbreviation: PCA3B), 9 ,9-dimethyl-N-phenyl-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]fluoren-2-amine (abbreviation: PCBAF), N-phenyl-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]spiro-9,9'-bifluoren-2-amine (abbreviation: PCBASF), 3-[N-(9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3,6-Bis[N-(9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA2), 3-[N-(1-naphthyl)-N-(9-phenylcarbazole-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1), 3,[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA1), 3,6-Bis[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA2), 3,6-Bis[N-(4-diphenylaminophenyl)-N-(1 Examples include -naphthyl)amino]-9-phenylcarbazole (abbreviation: PCzTPN2), 2-[N-(9-phenylcarbazole-3-yl)-N-phenylamino]spiro-9,9'-bifluorene (abbreviation: PCASF), N-[4-(9H-carbazole-9-yl)phenyl]-N-(4-phenyl)phenylaniline (abbreviation: YGA1BP), N,N'-bis[4-(carbazole-9-yl)phenyl]-N,N'-diphenyl-9,9-dimethylfluorene-2,7-diamine (abbreviation: YGA2F), and 4,4',4''-tris(carbazole-9-yl)triphenylamine (abbreviation: TCTA).

[0176] In addition to the above, other examples of carbazole derivatives include 3-[4-(9-phenanthryl)-phenyl]-9-phenyl-9H-carbazole (abbreviated as PCPPn), 3-[4-(1-naphthyl)-phenyl]-9-phenyl-9H-carbazole (abbreviated as PCPN), 1,3-bis(N-carbazolyl)benzene (abbreviated as mCP), 4,4'-di(N-carbazolyl)biphenyl (abbreviated as CBP), 3,6-bis(3,5-diphenylphenyl)-9-phenylcarbazole (abbreviated as CzTP), 1,3,5-tris[4-(N-carbazolyl)phenyl]benzene (abbreviated as TCPB), and 9-[4-(10-phenyl-9-anthracenyl)phenyl]-9H-carbazole (abbreviated as CzPA).

[0177] Furthermore, specific examples of the above-mentioned furan derivatives (organic compounds having a furan ring) include 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzofuran) (abbreviation: DBF3P-II) and 4-{3-[3-(9-phenyl-9H-fluoren-9-yl)phenyl]phenyl}dibenzofuran (abbreviation: mmDBFFLBi-II).

[0178] Furthermore, specific examples of the above-mentioned thiophene derivatives (organic compounds having a thiophene ring) include 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzothiophene) (abbreviated as DBT3P-II), 2,8-diphenyl-4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]dibenzothiophene (abbreviated as DBTFLP-III), and 4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]-6-phenyldibenzothiophene (abbreviated as DBTFLP-IV), which are organic compounds having a thiophene ring.

[0179] Furthermore, the above aromatic amines specifically include 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviated as NPB or α-NPD), N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (abbreviated as TPD), 4,4'-bis[N-(spiro-9,9'-bifluoren-2-yl)-N-phenylamino]biphenyl (abbreviated as BSPB), 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviated as BPAFLP), and 4-phenyl-3 '-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: mBPAFLP), N-(9,9-dimethyl-9H-fluoren-2-yl)-N-{9,9-dimethyl-2-[N'-phenyl-N'-(9,9-dimethyl-9H-fluoren-2-yl)amino]-9H-fluoren-7-yl}phenylamine (abbreviation: DFLADFL), N-(9,9-dimethyl-2-diphenylamino-9H-fluoren-7-yl)diphenylamine (abbreviation: DPNF), 2-[N-(4-diphenylaminophenyl)-N-phenylamino]spiro-9 ,9'-bifluorene (abbreviation: DPASF), 2,7-bis[N-(4-diphenylaminophenyl)-N-phenylamino]-spiro-9,9'-bifluorene (abbreviation: DPA2SF), 4,4',4''-tris[N-(1-naphthyl)-N-phenylamino]triphenylamine (abbreviation: 1'-TNATA), 4,4',4''-tris(N,N-diphenylamino)triphenylamine (abbreviation: TDATA), 4,4',4''-tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine (abbreviation: m-MTDATA), N, N'-di(p-tolyl)-N,N'-diphenyl-p-phenylenediamine (abbreviation: DTDPPA), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), DNTPD, 1,3,5-tris[N-(4-diphenylaminophenyl)-N-phenylamino]benzene (abbreviation: DPA3B), N-(4-biphenyl)-6,N-diphenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BnfABP), N,N-bis(4-biphenyl)-6-phenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf), 4,4'-bis(6-phenylbenzo[b]naphtho[1,2-d]furan-8-yl)-4''-phenyltriphenylamine (abbreviation: BnfBB1BP), N,N-bis(4-biphenyl)benzo[b]naphtho[1,2-d]furan-6-amine (abbreviation: BBABnf(6)), N,N-bis(4-biphenyl)benzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf(8)) ), N,N-bis(4-biphenyl)benzo[b]naphtho[2,3-d]furan-4-amine (abbreviation: BBABnf(II)(4)), N,N-bis[4-(dibenzofuran-4-yl)phenyl]-4-amino-p-terphenyl (abbreviation: DBfBB1TP), N-[4-(dibenzothiophen-4-yl)phenyl]-N-phenyl-4-biphenylamine (abbreviation: ThBA1BP), 4-(2-naphthyl)-4',4''-diphenyltriphenyl Min (abbreviation: BBAβNB), 4-[4-(2-naphthyl)phenyl]-4',4''-diphenyltriphenylamine (abbreviation: BBAβNBi), 4,4'-diphenyl-4''-(6;1'-binaphthyl-2-yl)triphenylamine (abbreviation: BBAαNβNB), 4,4'-diphenyl-4''-(7;1'-binaphthyl-2-yl)triphenylamine (abbreviation: BBAαNβNB-03), 4,4'-diphenyl-4''-(7-phenyl)na Phthyl-2-yltriphenylamine (abbreviation: BBAPβNB-03), 4,4'-diphenyl-4''-(6;2'-binaphthyl-2-yl)triphenylamine (abbreviation: BBA(βN2)B), 4,4'-diphenyl-4''-(7;2'-binaphthyl-2-yl)triphenylamine (abbreviation: BBA(βN2)B-03), 4,4'-diphenyl-4''-(4;2'-binaphthyl-1-yl)triphenylamine (abbreviation: BBAβNαNB), 4,4'-Diphenyl-4''-(5;2'-binaphthyl-1-yl)triphenylamine (abbreviation: BBAβNαNB-02), 4-(4-biphenylyl)-4'-(2-naphthyl)-4''-phenyltriphenylamine (abbreviation: TPBiAβNB), 4-(3-biphenylyl)-4'-[4-(2-naphthyl)phenyl]-4''-phenyltriphenylamine (abbreviation: mTPBiAβNBi), 4-(4-biphenylyl)-4'-[4-(2-naphthyl)phenyl]-4' '-phenyltriphenylamine (abbreviation: TPBiAβNBi), 4-phenyl-4'-(1-naphthyl)triphenylamine (abbreviation: αNBA1BP), 4,4'-bis(1-naphthyl)triphenylamine (abbreviation: αNBB1BP), 4,4'-diphenyl-4''-[4'-(carbazole-9-yl)biphenyl-4-yl]triphenylamine (abbreviation: YGTBi1BP), 4'-[4-(3-phenyl-9H-carbazole-9-yl)phenyl]tris(1, 1'-biphenyl-4-yl)amine (abbreviation: YGTBi1BP-02), 4-[4'-(carbazole-9-yl)biphenyl-4-yl]-4'-(2-naphthyl)-4''-phenyltriphenylamine (abbreviation: YGTBiβNB), N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-N-[4-(1-naphthyl)phenyl]-9,9'-spirobio[9H-fluorene]-2-amine (abbreviation: PCBNBSF), N,N-bis([1,1'-bi Phenyl]-4-yl)-9,9'-spirobio[9H-fluorene]-2-amine (abbreviation: BBASF), N,N-bis([1,1'-biphenyl]-4-yl)-9,9'-spirobio[9H-fluorene]-4-amine (abbreviation: BBASF(4)), N-(1,1'-biphenyl-2-yl)-N-(9,9-dimethyl-9H-fluorene-2-yl)-9,9'-spirobio[9H-fluorene]-4-amine (abbreviation: oFBiSF), N-(4-biphenyl)-N-(9,9-dimethyl-9H-fluoren-2-yl)dibenzofuran-4-amine (abbreviation: FrBiF), N-[4-(1-naphthyl)phenyl]-N-[3-(6-phenyldibenzofuran-4-yl)phenyl]-1-naphthylamine (abbreviation: mPDBfBNBN), 4-phenyl-4'-[4-(9-phenylfluoren-9-yl)phenyl]triphenylamine (abbreviation: BPAFLBi), N,N-bis(9,9-dimethyl-9H-fluoren-2- Examples include N,N-bis(9,9-dimethyl-9H-fluoren-4-amine), N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobio-9H-fluoren-3-amine, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobio-9H-fluoren-2-amine, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobio-9H-fluoren-1-amine, etc.

[0180] In addition, polymer compounds (oligomers, dendrimers, polymers, etc.) such as poly(N-vinylcarbazole) (abbreviated as PVK), poly(4-vinyltriphenylamine) (abbreviated as PVTPA), poly[N-(4-{N'-[4-(4-diphenylamino)phenyl]phenyl-N'-phenylamino}phenyl)methacrylamide] (abbreviated as PTPDMA), and poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)benzidine] (abbreviated as Poly-TPD) can be used as hole transport materials. Alternatively, polymer compounds to which acids such as poly(3,4-ethylenedioxythiophene) / poly(styrenesulfonic acid) (abbreviated as PEDOT / PSS) and polyaniline / poly(styrenesulfonic acid) (PAni / PSS) can be added can also be used.

[0181] However, the hole transport material is not limited to the above, and various known materials may be used as a hole transport material by combining one or more of them.

[0182] The hole injection layers (111, 111a, 111b) can be formed using various known film deposition methods, for example, by vacuum deposition.

[0183] <Hole transport layer> The hole transport layers (112, 112a, 112b) are layers that transport holes injected from the first electrode 101 by the hole injection layers (111, 111a, 111b) to the light-emitting layers (113, 113a, 113b). The hole transport layers (112, 112a, 112b) are layers containing a hole-transporting material. Therefore, the hole transport layers (112, 112a, 112b) can use the same hole-transporting material that can be used in the hole injection layers (111, 111a, 111b).

[0184] In the light-emitting device shown in this embodiment, the same organic compound used in the hole transport layers (112, 112a, 112b) can be used in the light-emitting layers (113, 113a, 113b). Using the same organic compound in both the hole transport layers (112, 112a, 112b) and the light-emitting layers (113, 113a, 113b) is preferable because it allows for more efficient transport of holes from the hole transport layers (112, 112a, 112b) to the light-emitting layers (113, 113a, 113b).

[0185] <Luminous layer> The light-emitting layers (113, 113a, 113b) are layers containing a light-emitting material. The light-emitting material that can be used in the light-emitting layers (113, 113a, 113b) can be any material that exhibits a light-emitting color such as blue, purple, blue-violet, green, yellow-green, yellow, orange, or red. Furthermore, if there are multiple light-emitting layers, a configuration exhibiting different light-emitting colors can be achieved by using different light-emitting materials in each layer (for example, white light emission obtained by combining complementary light-emitting colors). Additionally, a laminated structure in which each light-emitting layer contains a different light-emitting material is also possible.

[0186] Furthermore, the light-emitting layers (113, 113a, 113b) may contain one or more types of organic compounds (host materials, etc.) in addition to the light-emitting substance (guest material).

[0187] Furthermore, when multiple host materials are used in the light-emitting layers (113, 113a, 113b), it is preferable to use a material with a larger energy gap than the energy gaps of the existing guest material and the first host material as the newly added second host material. It is also preferable that the lowest singlet excitation energy level (S1 level) of the second host material is higher than the S1 level of the first host material, and that the lowest triplet excitation energy level (T1 level) of the second host material is higher than the T1 level of the guest material. Furthermore, it is preferable that the lowest triplet excitation energy level (T1 level) of the second host material is higher than the T1 level of the first host material. With this configuration, an excitation complex can be formed using two types of host materials. In order to efficiently form the excitation complex, it is particularly preferable to combine a compound that readily accepts holes (hole transport material) with a compound that readily accepts electrons (electron transport material). This configuration also enables the simultaneous achievement of high efficiency, low voltage, and long lifespan.

[0188] The organic compounds used as the host material (including the first and second host materials) can be any organic compound that satisfies the requirements for a host material used in the light-emitting layer, such as hole-transporting materials that can be used in the aforementioned hole-transporting layers (112, 112a, 112b), or electron-transporting materials that can be used in the electron-transporting layers (114, 114a, 114b) described later. It may also be an excited complex composed of multiple types of organic compounds (the first and second host materials). An excited complex (also called an exciplex) that forms an excited state with multiple types of organic compounds has an extremely small difference between the S1 and T1 levels and functions as a TADF material capable of converting triplet excitation energy into singlet excitation energy. Furthermore, as a combination of multiple types of organic compounds that form an excited complex, for example, it is preferable that one has a π-electron-deficient heteroaromatic ring and the other has a π-electron-rich heteroaromatic ring. Furthermore, as a combination for forming the excitation complex, one of the components may be a phosphorescent material such as an iridium, rhodium, or platinum-based organometallic complex, or a metal complex.

[0189] There are no particular limitations on the luminescent material that can be used in the luminescent layers (113, 113a, 113b). A luminescent material that converts singlet excitation energy into visible light emission, or a luminescent material that converts triplet excitation energy into visible light emission, can be used.

[0190] <<Luminescent material that converts singlet excitation energy into light emission>> Examples of luminescent materials that can be used in the light-emitting layer 113 to convert singlet excitation energy into light include the following fluorescent materials (fluorescent materials). For example, pyrene derivatives, anthracene derivatives, triphenylene derivatives, fluorene derivatives, carbazole derivatives, dibenzothiophene derivatives, dibenzofuran derivatives, dibenzoquinoxaline derivatives, quinoxaline derivatives, pyridine derivatives, pyrimidine derivatives, phenanthrene derivatives, and naphthalene derivatives. Pyrene derivatives are particularly preferred because they have a high luminescence quantum yield. Specific examples of pyrene derivatives include N,N'-bis(3-methylphenyl)-N,N'-bis[3-(9-phenyl-9H-fluoren-9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6mMemFLPAPrn), (N,N'-diphenyl-N,N'-bis[4-(9-phenyl-9H-fluoren-9-yl)phenyl]pyrene-1,6-diamine) (abbreviation: 1,6FLPAPrn), N,N'-bis(dibenzofuran-2-yl)-N,N'-diphenylpyrene-1,6-diamine (abbreviation: 1,6FrAPrn), and N,N'-bis(dibenzothiophen-2-yl)-N Examples include N'-diphenylpyrene-1,6-diamine (abbreviation: 1,6ThAPrn), N,N'-(pyrene-1,6-diyl)bis[(N-phenylbenzo[b]naphtho[1,2-d]furan)-6-amine] (abbreviation: 1,6BnfAPrn), N,N'-(pyrene-1,6-diyl)bis[(N-phenylbenzo[b]naphtho[1,2-d]furan)-8-amine] (abbreviation: 1,6BnfAPrn-02), and N,N'-(pyrene-1,6-diyl)bis[(6,N-diphenylbenzo[b]naphtho[1,2-d]furan)-8-amine] (abbreviation: 1,6BnfAPrn-03).

[0191] Also, 5,6-bis[4-(10-phenyl-9-antryl)phenyl]-2,2'-bipyridine (abbreviation: PAP2BPy), 5,6-bis[4'-(10-phenyl-9-antryl)biphenyl-4-yl]-2,2'-bipyridine (abbreviation: PAPP2BPy), N,N'-bis[4-(9H-carbazole-9-yl)phenyl]-N,N'-diphenylstilbene-4,4'-diamine (abbreviation: YGA2S), 4-(9H-carbazole (9-yl)-4'-(10-phenyl-9-anthryl)triphenylamine (abbreviation: YGAPA), 4-(9H-carbazole-9-yl)-4'-(9,10-diphenyl-2-anthryl)triphenylamine (abbreviation: 2YGAPPA), N,9-diphenyl-N-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole-3-amine (abbreviation: PCAPA), 4-(10-phenyl-9-anthryl)-4'- (9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBAPA), 4-[4-(10-phenyl-9-antryl)phenyl]-4'-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBAPBA), perylene, 2,5,8,11-tetra-tert-butylperylene (abbreviation: TBP), N,N''-(2-tert-butylanthracene-9,10-diyldi-4,1-phenyl) Nilen)bis[N,N',N'-triphenyl-1,4-phenylenediamine] (abbreviated as DPABPA), N,9-diphenyl-N-[4-(9,10-diphenyl-2-anthryl)phenyl]-9H-carbazole-3-amine (abbreviated as 2PCAPPA), N-[4-(9,10-diphenyl-2-anthryl)phenyl]-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviated as 2DPAPPA), etc. can be used.

[0192] Also, N-[9,10-bis(1,1'-biphenyl-2-yl)-2-anthryl]-N,9-diphenyl-9H-carbazole-3-amine (abbreviation: 2PCABPhA), N-(9,10-diphenyl-2-anthryl)-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPA), N-[9,10-bis(1,1'-biphenyl-2-yl)-2-anthryl]-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPABPhA), 9,10-bis(1,1'-biphenyl- 2-yl)-N-[4-(9H-carbazole-9-yl)phenyl]-N-phenylanthracene-2-amine (abbreviation: 2YGABPhA), N,N,9-triphenylanthracene-9-amine (abbreviation: DPhAPhA), coumarin 545T, N,N'-diphenylquinacridone (abbreviation: DPQd), rubren, 5,12-bis(1,1'-biphenyl-4-yl)-6,11-diphenyltetracene (abbreviation: BPT), 2-(2-{2-[4-(dimethylamino)phenyl]ethenyl}-6-methyl-4H-pyran-4-yl DCM1)propanedinitrile, 2-{2-methyl-6-[2-(2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinoridine-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (DCM2), N,N,N',N'-tetrakis(4-methylphenyl)tetracene-5,11-diamine (p-mPhTD), 7,14-diphenyl-N,N,N',N'-tetrakis(4-methylphenyl)acenaphtho[1,2-a]fluorantene-3,10-diamine (p -mPhAFD), 2-{2-isopropyl-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinoridine-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTI), 2-{2-tert-butyl-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinoridine-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTB), 2-(2,6-Bis{2-[4-(dimethylamino)phenyl]ethenyl}-4H-pyran-4-ylidene)propanedinitrile (abbreviation: BisDCM), 2-{2,6-Bis[2-(8-methoxy-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinoridine-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: BisDCJTM), 1,6BnfAP Examples include rn-03, 3,10-bis[N-(9-phenyl-9H-carbazole-2-yl)-N-phenylamino]naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3,10PCA2Nbf(IV)-02), and 3,10-bis[N-(dibenzofuran-3-yl)-N-phenylamino]naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3,10FrA2Nbf(IV)-02). In particular, pyrenediamine compounds such as 1,6FLPAPrn, 1,6mMemFLPAPrn, and 1,6BnfAPrn-03 can be used.

[0193] <<Luminescent material that converts triplet excitation energy into light emission>> Next, examples of light-emitting materials that can be used in the light-emitting layer 113 to convert triplet excitation energy into light include phosphorescent materials (phosphorescent materials) or thermally activated delayed fluorescence (TADF) materials that exhibit thermally activated delayed fluorescence.

[0194] A phosphorescent material is a compound that exhibits phosphorescence and does not fluoresce at any temperature range above low temperatures (e.g., 77K) and below room temperature (i.e., between 77K and 313K). The phosphorescent material preferably contains a metal element with strong spin-orbit interaction, and examples include organometallic complexes, metal complexes (platinum complexes), and rare earth metal complexes. Specifically, transition metal elements are preferred, and particularly platinum group elements (ruthenium (Ru), rhodium (Rh), palladium (Pd), osmium (Os), iridium (Ir), or platinum (Pt)) are preferred. The presence of iridium is especially preferable because it increases the transition probability involved in the direct transition between the singlet ground state and the triplet excited state.

[0195] ≪Phosphorescent materials (450nm to 570nm: blue or green)≫ Examples of phosphorescent materials that exhibit blue or green light and have a peak wavelength of emission spectrum between 450 nm and 570 nm include the following:

[0196] For example, Tris{2-[5-(2-methylphenyl)-4-(2,6-dimethylphenyl)-4H-1,2,4-triazole-3-yl-κN 2]phenyl-κC}iridium(III) (abbreviation: [Ir(mpptz-dmp)3]), tris(5-methyl-3,4-diphenyl-4H-1,2,4-triazolato)iridium(III) (abbreviation: [Ir(Mptz)3]), tris[4-(3-biphenyl)-5-isopropyl-3-phenyl-4H-1,2,4-triazolato]iridium(III) (abbreviation: [Ir(iPr5btz)3]), organometallic complexes having a 4H-triazole ring such as tris[3-(5-biphenyl)-5-isopropyl-4-phenyl-4H-1,2,4-triazolato]iridium(III) (abbreviation: [Ir(iPr5btz)3]), tris[3-methyl-1-(2-methylphenyl)-5-phenyl-1H-1,2,4-triazolato Organometallic complexes having a 1H-triazole ring, such as iridium(III) (abbreviation: [Ir(Mptz1-mp)3]), tris(1-methyl-5-phenyl-3-propyl-1H-1,2,4-triazolato)iridium(III) (abbreviation: [Ir(Prptz1-Me)3]), fac-tris[1-(2,6-diisopropylphenyl)-2-phenyl-1H-imidazole]iridium(III) (abbreviation: [Ir(iPrpmi)3]), tris[3-(2,6-dimethylphenyl)-7-methylimidazo[1,2-f]phenanthridine]iridium(III) (abbreviation: [Ir(dmpimpt-Me)3]), and bis[2-(4',6'-difluorophenyl)pyridinate-N,C 2’ Iridium(III) tetrakis(1-pyrazolyl) borate (abbreviation: FIr6), bis[2-(4',6'-difluorophenyl)pyridinate-N,C2']iridium(III) picolinate (abbreviation: FIrpic), bis{2-[3',5'-bis(trifluoromethyl)phenyl]pyridinate-N,C 2’ Iridium(III) picolinate (abbreviation: [Ir(CF3ppy)2(pic)]), bis[2-(4',6'-difluorophenyl)pyridinate-N,C 2’ Examples include organometallic complexes that use phenylpyridine derivatives having electron-withdrawing groups as ligands, such as iridium(III) acetylacetonate (abbreviated as Fir(acac)).

[0197] ≪Phosphorescent materials (495nm to 590nm: green or yellow)≫ Examples of phosphorescent materials that exhibit a green or yellow color and have a peak wavelength of emission spectrum between 495 nm and 590 nm include the following:

[0198] For example, tris(4-methyl-6-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mppm)3]), tris(4-t-butyl-6-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(tBuppm)3]), (acetylacetonato)bis(6-methyl-4-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mppm)2(acac)]), (acetylacetonato)bis(6-tert- (Ir(tBuppm)2(acac)), (acetylacetonato)bis[6-(2-norbornyl)-4-phenylpyrimidinato]iridium(III) (abbreviation: [Ir(nbppm)2(acac)]), (acetylacetonato)bis[5-methyl-6-(2-methylphenyl)-4-phenylpyrimidinato]iridium(III) (abbreviation: [Ir(mpmppm Organometallic iridium(III) having a pyrimidine ring, such as (acetylacetonato)bis{4,6-dimethyl-2-[6-(2,6-dimethylphenyl)-4-pyrimidinyl-κN3]phenyl-κC}iridium(III) (abbreviation: [Ir(dmppm-dmp)2(acac)]), (acetylacetonato)bis(4,6-diphenylpyrimidinato)iridium(III) (abbreviation: [Ir(dppm)2(acac)]), iridium complexes having a pyrazine ring, such as (acetylacetonato)bis(3,5-dimethyl-2-phenylpyradinato)iridium(III) (abbreviation: [Ir(mppr-Me)2(acac)]), (acetylacetonato)bis(5-isopropyl-3-methyl-2-phenylpyradinato)iridium(III) (abbreviation: [Ir(mppr-iPr)2(acac)]), and tris(2-phenylpyridinato-N,C) 2’Iridium(III) (abbreviation: [Ir(ppy)3]), bis(2-phenylpyridinate-N,C) 2’ Iridium(III) acetylacetonate (abbreviation: [Ir(ppy)2(acac)]), bis(benzo[h]quinolinate)iridium(III) acetylacetonate (abbreviation: [Ir(bzq)2(acac)]), tris(benzo[h]quinolinate)iridium(III) (abbreviation: [Ir(bzq)3]), tris(2-phenylquinolinate-N,C) 2’ Iridium(III) (abbreviation: [Ir(pq)3]), bis(2-phenylquinolinato-N,C) 2’Iridium(III) acetylacetonate (abbreviation: [Ir(pq)2(acac)]), bis[2-(2-pyridinyl-κN)phenyl-κC][2-(4-phenyl-2-pyridinyl-κN)phenyl-κC] Iridium(III) (abbreviation: [Ir(ppy)2(4dppy)]), bis[2-(2-pyridinyl-κN)phenyl-κC][2-(4-methyl-5-phenyl-2-pyridinyl [-κN)phenyl-κC], [2-d3-methyl-8-(2-pyridinyl-κN)benzofl[2,3-b]pyridinyl-κC]bis[2-(5-d3-methyl-2-pyridinyl-κN2)phenyl-κC]iridium(III) (abbreviation: Ir(5mppy-d3)2(mbfpypy-d3)), [2-(methyl-d3)-8-[4-(1-methylethyl-1-d)-2-pyridinyl-κN]benzofl [2,3-b]pyridinyl-7-yl-κC]bis[5-(methyl-d3)-2-[5-(methyl-d3)-2-pyridinyl-κN]phenyl-κC]iridium(III) (abbreviation: Ir(5mtpy-d6)2(mbfpypy-iPr-d4)), [2-d3-methyl-(2-pyridinyl-κN)benzofloflo[2,3-b]pyridinyl-κC]bis[2-(2-pyridinyl-κN)phenyl-κC Organometallic iridium complexes having a pyridine ring, such as iridium(III) (abbreviation: Ir(ppy)2(mbfpypy-d3)), [2-(4-methyl-5-phenyl-2-pyridinyl-κN)phenyl-κC]bis[2-(2-pyridinyl-κN)phenyl-κC]iridium(III) (abbreviation: Ir(ppy)2(mdppy)), and bis(2,4-diphenyl-1,3-oxazolato-N,C 2’ Iridium(III) acetylacetonate (abbreviation: [Ir(dpo)2(acac)]), bis{2-[4'-(perfluorophenyl)phenyl]pyridinate-N,C 2’ Iridium(III) acetylacetonate (abbreviation: [Ir(p-PF-ph)2(acac)]), bis(2-phenylbenzothiazolat-N,C) 2’Examples include organometallic complexes such as iridium(III) acetylacetonate (abbreviated as [Ir(bt)2(acac)]), as well as rare earth metal complexes such as tris(acetylacetonate)(monophenanthroline)terbium(III) (abbreviated as [Tb(acac)3(Phen)]).

[0199] ≪Phosphorescent materials (570nm to 750nm: yellow or red)≫ Examples of phosphorescent materials that exhibit a yellow or red color and have a peak wavelength of emission spectrum between 570 nm and 750 nm include the following:

[0200] For example, (diisobutyrylmethanato)bis[4,6-bis(3-methylphenyl)pyrimidinato]iridium(III) (abbreviation: [Ir(5mdppm)2(dibm)]), bis[4,6-bis(3-methylphenyl)pyrimidinato](dipivaloylmethanato)iridium(III) (abbreviation: [Ir(5mdppm)2(dpm)]), (dipivaloylmethanato)bis[4,6-di(naphthalene-1-yl)pyrimidinato]iridium(III) (abbreviation: [Ir(d1npm)2(dpm)]), and other pyramidal compounds. Organometallic complexes having a limidine ring: (acetylacetonato)bis(2,3,5-triphenylpyrazinato)iridium(III) (abbreviation: [Ir(tppr)2(acac)]), bis(2,3,5-triphenylpyrazinato)(dipivaloylmethanato)iridium(III) (abbreviation: [Ir(tppr)2(dpm)]), bis{4,6-dimethyl-2-[3-(3,5-dimethylphenyl)-5-phenyl-2-pyrazinyl-κN]phenyl-κC}(2,6-dimethyl-3,5-heptanedionato-κ 2 O,O') Iridium(III) (abbreviation: [Ir(dmdppr-P)2(dibm)]), bis{4,6-dimethyl-2-[5-(4-cyano-2,6-dimethylphenyl)-3-(3,5-dimethylphenyl)-2-pyradinyl-κN]phenyl-κC}(2,2,6,6-tetramethyl-3,5-heptanedionato-κ 2O,O') Iridium(III) (abbreviation: [Ir(dmdppr-dmCP)2(dpm)]), bis[2-(5-(2,6-dimethylphenyl)-3-(3,5-dimethylphenyl)-2-pyrazinyl-κN)-4,6-dimethylphenyl-κC](2,2',6,6'-tetramethyl-3,5-heptanedionato-κ2O,O') Iridium(III) (abbreviation: [Ir(dmdppr-dmp)2(dpm)]), (acetylacetonato)bis[2-methyl-3-phenylquinoxalinato-N,C 2’ Iridium(III) (abbreviation: [Ir(mpq)2(acac)]), (acetylacetonato)bis(2,3-diphenylquinoxalinato-N,C) 2’ Organometallic complexes having a pyrazine ring, such as iridium(III) (abbreviation: [Ir(dpq)2(acac)]), (acetylacetonato)bis[2,3-bis(4-fluorophenyl)quinoxalinato]iridium(III) (abbreviation: [Ir(Fdpq)2(acac)]), and tris(1-phenylisoquinolinato-N,C) 2’ Iridium(III) (abbreviation: [Ir(piq)3]), bis(1-phenylisoquinolinato-N,C) 2’ Iridium(III) acetylacetonate (abbreviation: [Ir(piq)2(acac)]), bis[4,6-dimethyl-2-(2-quinolinyl-κN)phenyl-κC](2,4-pentanedionato-κ 2 Examples include organometallic complexes having a pyridine ring, such as O,O')iridium(III) (abbreviation: [Ir(dmpqn)2(acac)]), platinum complexes such as 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrin platinum(II) (abbreviation: [PtOEP]), and rare earth metal complexes such as tris(1,3-diphenyl-1,3-propanedionato)(monophenanthroline)europium(III) (abbreviation: [Eu(DBM)3(Phen)]) and tris[1-(2-tenoyl)-3,3,3-trifluoroacetonato](monophenanthroline)europium(III) (abbreviation: [Eu(TTA)3(Phen)]).

[0201] ≪TADF material≫ Furthermore, the following materials can be used as TADF materials. A TADF material is a material in which the difference between the S1 level and the T1 level is small (preferably 0.2 eV or less), the triplet excited state can be upconverted to the singlet excited state with a small amount of thermal energy (reverse intersystem crossing), and the emission (fluorescence) from the singlet excited state is efficiently exhibited. Furthermore, conditions for efficiently obtaining thermally activated delayed fluorescence include an energy difference between the triplet excited energy level and the singlet excited energy level being 0 eV or more and 0.2 eV or less, preferably 0 eV or more and 0.1 eV or less. In addition, delayed fluorescence in TADF materials refers to emission that has a spectrum similar to normal fluorescence but with a remarkably long lifetime. Its lifetime is 1 × 10⁻⁶ -6 For more than a second, preferably 1 × 10⁻⁶ seconds. -3 It is more than a second.

[0202] Examples of TADF materials include fullerenes and their derivatives, acridine derivatives such as proflavin, and eosin. Also, metal-containing porphyrins containing magnesium (Mg), zinc (Zn), cadmium (Cd), tin (Sn), platinum (Pt), indium (In), or palladium (Pd) are also examples. Examples of metal-containing porphyrins include protoporphyrin-tin fluoride complexes (abbreviated as SnF2(Proto IX)), mesoporphyrin-tin fluoride complexes (abbreviated as SnF2(Meso IX)), hematoporphyrin-tin fluoride complexes (abbreviated as SnF2(Hemato IX)), coproporphyrin tetramethyl ester-tin fluoride complexes (abbreviated as SnF2(Copro III-4Me)), octaethylporphyrin-tin fluoride complexes (abbreviated as SnF2(OEP)), etioporphyrin-tin fluoride complexes (abbreviated as SnF2(Etio I)), and octaethylporphyrin-platinum chloride complexes (abbreviated as PtCl2OEP).

[0203] [ka]

[0204] Other examples include 2-(biphenyl-4-yl)-4,6-bis(12-phenylindoro[2,3-a]carbazol-11-yl)-1,3,5-triazine (abbreviated as PIC-TRZ), 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol-9-yl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviated as PCCzPTzn), and 2-[4-(10H-phenoxy [Sadin-10-yl)phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviation: PXZ-TRZ), 3-[4-(5-phenyl-5,10-dihydrophenazine-10-yl)phenyl]-4,5-diphenyl-1,2,4-triazole (abbreviation: PPZ-3TPT), 3-(9,9-dimethyl-9H-acridine-10-yl)-9H-xanthene-9-one (abbreviation: ACRXTN), bis[4-(9, 9-dimethyl-9,10-dihydroacridine)phenyl]sulfone (abbreviation: DMAC-DPS), 10-phenyl-10H,10'H-spiro[acridine-9,9'-anthracene]-10'-one (abbreviation: ACRSA), 4-(9'-phenyl-3,3'-bi-9H-carbazole-9-yl)benzoflo[3,2-d]pyrimidine (abbreviation: 4PCCzBfpm), 4-[4-(9'-phenyl-3,3'- Hetero-aromatic compounds having π-electron-rich hetero-aromatic compounds and π-electron-deficient hetero-aromatic compounds such as bi-9H-carbazole-9-yl)phenyl]benzofl[3,2-d]pyrimidine (abbreviation: 4PCCzPBfpm) and 9-[3-(4,6-diphenyl-1,3,5-triazine-2-yl)phenyl]-9'-phenyl-2,3'-bi-9H-carbazole (abbreviation: mPCCzPTzn-02) may also be used.

[0205] Furthermore, a material in which a π-electron-rich heteroaromatic compound and a π-electron-deficient heteroaromatic compound are directly bonded is particularly preferable because both the donor properties of the π-electron-rich heteroaromatic compound and the acceptor properties of the π-electron-deficient heteroaromatic compound become stronger, and the energy difference between the singlet excited state and the triplet excited state becomes smaller. In addition, a TADF material (TADF100) in which the singlet excited state and the triplet excited state are in thermal equilibrium may be used as the TADF material. Since such a TADF material has a shorter luminescence lifetime (excitation lifetime), it is possible to suppress the decrease in efficiency in the high-brightness region of the light-emitting element.

[0206] [ka]

[0207] In addition to the above, other materials that have the function of converting triplet excitation energy into light emission include nanostructures of transition metal compounds having a perovskite structure. Nanostructures of metal halogen perovskites are particularly desirable. Nanoparticles and nanorods are preferred as such nanostructures.

[0208] In the light-emitting layers (113, 113a, 113b, 113c), the organic compounds (host materials, etc.) used in combination with the light-emitting material (guest material) described above may be one or more materials having an energy gap larger than the energy gap of the light-emitting material (guest material).

[0209] ≪Host materials for fluorescence emission≫ When the light-emitting material used in the light-emitting layer (113, 113a, 113b, 113c) is a fluorescent light-emitting material, it is preferable to use an organic compound (host material) that has a large singlet excited state energy level and a small triplet excited state energy level, or an organic compound with a high fluorescence quantum yield. Therefore, any organic compound that satisfies these conditions can be used, such as the hole transport material (described above) and electron transport material (described below) shown in this embodiment.

[0210] Although some of these overlap with the specific examples mentioned above, from the perspective of preferred combinations with luminescent substances (fluorescent substances), examples of organic compounds (host materials) include condensed polycyclic aromatic compounds such as anthracene derivatives, tetracene derivatives, phenanthrene derivatives, pyrene derivatives, chrysene derivatives, and dibenzo[g,p]chrysene derivatives.

[0211] Specific examples of organic compounds (host materials) that are preferable to use in combination with fluorescent luminescent substances include 9-phenyl-3-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviated as PCzPA), 3,6-diphenyl-9-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviated as DPCzPA), 3-[4-(1-naphthyl)-phenyl]-9-phenyl-9H-carbazole (abbreviated as PCPN), and 9,10-diphenylanthracene (abbreviated as :DPAnth), N,N-diphenyl-9-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole-3-amine (abbreviation: CzA1PA), 4-(10-phenyl-9-anthryl)triphenylamine (abbreviation: DPhPA), YGAPA, PCAPA, N,9-diphenyl-N-{4-[4-(10-phenyl-9-anthryl)phenyl]phenyl}-9H-carbazole-3-amine (abbreviation: PCAPBA), N-(9,10-diphenyl-2-anthryl)-N,9-di Phenyl-9H-carbazole-3-amine (abbreviation: 2PCAPA), 6,12-dimethoxy-5,11-diphenylchrysene, N,N,N',N',N'',N'',N''',N'''-octaphenyldibenzo[g,p]chrysene-2,7,10,15-tetraamine (abbreviation: DBC1), 9-[4-(10-phenyl-9-anthracenyl)phenyl]-9H-carbazole (abbreviation: CzPA), 7-[4-(10-phenyl-9-anthryl)phenyl]-7H-dibenzo[c,g]carbazole 6-[3-(9,10-diphenyl-2-anthryl)phenyl]-benzo[b]naphtho[1,2-d]furan (abbreviation: 2mBnfPPA), 9-phenyl-10-{4-(9-phenyl-9H-fluoren-9-yl)-biphenyl-4'-yl}anthracene (abbreviation: FLPPA), 9,10-bis(3,5-diphenylphenyl)anthracene (abbreviation: DPPA), 9,10-di(2-naphthyl)anthracene (abbreviation: DNA), 2-tert-butyl-9,10-di(2-naphthyl)anthracene (abbreviation: t-BuDNA), 9-(1-naphthyl)-10-(2-naphthyl)anthracene (abbreviation: α,βADN), 2-(10-phenylanthracene-9-yl)dibenzofuran, 2-(10-phenyl-9-anthracenyl)-benzo[b]naphtho[2,3-d]furan (abbreviation: Bnf(II)PhA), 9-(1-naphthyl)-10-[4-(2-naphthyl)phenyl]anthracene (abbreviation: αN-βNPAnth), 9-(2-naphthyl)-10-[3-(2-naphthyl)phenyl]anthracene (abbreviation: βN-mβNPAn Examples include 1-[4-(10-[1,1'-biphenyl]-4-yl-9-anthracenyl)phenyl]-2-ethyl-1H-benzimidazole (abbreviated as EtBImPBPhA), 9,9'-biantryl (abbreviated as BANT), 9,9'-(stilbene-3,3'-diyl)diphenanthrene (abbreviated as DPNS), 9,9'-(stilbene-4,4'-diyl)diphenanthrene (abbreviated as DPNS2), 1,3,5-tri(1-pyrenyl)benzene (abbreviated as TPB3), 5,12-diphenyltetracene, and 5,12-bis(biphenyl-2-yl)tetracene.

[0212] ≪Host materials for phosphorescence≫ Furthermore, when the luminescent material used in the luminescent layers (113, 113a, 113b, 113c) is a phosphorescent material, it is sufficient to select an organic compound (host material) to combine with it that has a triplet excitation energy greater than the triplet excitation energy of the luminescent material (the energy difference between the ground state and the triplet excited state). When using multiple organic compounds (for example, a first host material and a second host material (or assist material), etc.) in combination with the luminescent material to form an excited complex, it is preferable to mix these multiple organic compounds with the phosphorescent material.

[0213] This configuration allows for efficient emission using ExTET (Exciplex-Triplet Energy Transfer), which is energy transfer from the excited complex to the luminescent material. The combination of organic compounds should ideally be one that readily forms an excited complex, and a combination of a compound that readily accepts holes (hole transport material) and a compound that readily accepts electrons (electron transport material) is particularly preferable.

[0214] In addition, although some of these overlap with the specific examples mentioned above, from the perspective of preferred combinations with luminescent substances (phosphorescent substances), suitable organic compounds (host materials, assist materials) include aromatic amines (organic compounds having an aromatic amine skeleton), carbazole derivatives (organic compounds having a carbazole ring), dibenzothiophene derivatives (organic compounds having a dibenzothiophene ring), dibenzofuran derivatives (organic compounds having a dibenzofuran ring), oxadiazole derivatives (organic compounds having an oxadiazole ring), triazole derivatives (organic compounds having a triazole ring), and benzimidazole derivatives (benzo- Examples include organic compounds having a midazole ring, quinoxaline derivatives (organic compounds having a quinoxaline ring), dibenzoquinoxaline derivatives (organic compounds having a dibenzoquinoxaline ring), pyrimidine derivatives (organic compounds having a pyrimidine ring), triazine derivatives (organic compounds having a triazine ring), pyridine derivatives (organic compounds having a pyridine ring), bipyridine derivatives (organic compounds having a bipyridine ring), phenanthroline derivatives (organic compounds having a phenanthroline ring), phlodiazine derivatives (organic compounds having a phlodiazine ring), zinc-based or aluminum-based metal complexes, etc.

[0215] Furthermore, among the above-mentioned organic compounds, specific examples of aromatic amines and carbazole derivatives, which are organic compounds with high hole transport properties, are the same as the specific examples of hole transport materials described above, and all of these are preferred as host materials.

[0216] Furthermore, among the above organic compounds, specific examples of dibenzothiophene derivatives and dibenzofuran derivatives, which are organic compounds with high hole transport properties, include 4-{3-[3-(9-phenyl-9H-fluoren-9-yl)phenyl]phenyl}dibenzofuran (abbreviation: mmDBFFLBi-II), 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzofuran) (abbreviation: DBF3P-II), DBT3P-II, and 2,8-diphenyl Examples include nyl-4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]dibenzothiophene (abbreviated as DBTFLP-III), 4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]-6-phenyldibenzothiophene (abbreviated as DBTFLP-IV), and 4-[3-(triphenylene-2-yl)phenyl]dibenzothiophene (abbreviated as mDBTPTp-II), all of which are preferred as host materials.

[0217] Other preferred host materials include metal complexes having oxazole-based or thiazole ligands such as bis[2-(2-benzoxazolyl)phenolate]zinc(II) (abbreviated as ZnPBO) and bis[2-(2-benzothiazolyl)phenolate]zinc(II) (abbreviated as ZnBTZ).

[0218] Furthermore, among the above organic compounds, specific examples of organic compounds with high electron transport properties, such as oxadiazole derivatives, triazole derivatives, benzimidazole derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, quinazoline derivatives, and phenanthroline derivatives, include 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazole-2-yl]benzene (abbreviation: OXD-7), 9-[4-(5-phenyl-1,3,4-oxadiazole-2-yl)phenyl]-9H-carbazole (abbreviation: CO11), 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (abbreviation: TAZ), 2,2',2''-(1,3,5-benzenetriyl)tris(1-phenyl-1H-benzimidazole) (abbreviation: TPBI), 2-[3-(dibenzothiophen-4-yl)phenyl]-1-phenyl-1H-benzimidazole (abbreviation: mDBTBIm-II) Organic compounds containing heteroaromatic rings with polyazole rings, such as 4,4'-bis(5-methylbenzoxazole-2-yl)stilbene (abbreviation: BzOs), and compounds containing heteroaromatic rings with pyridine rings, such as vasophenanthroline (abbreviation: Bphen), vasocuproin (abbreviation: BCP), 2,9-di(naphthalene-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBphen), and 2,2-(1,3-phenylene)bis[9-phenyl-1,10-phenanthroline] (abbreviation: mPPhen2P). The compound is 2-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTPDBq-II), 2-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II), 2-[3'-(9H-carbazole-9-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mCzBPDBq), 2-[4-(3,6-diphenyl-9H-carbazole-9-yl)phenyl]dibenzo[f,Examples include [h]quinoxaline (abbreviation: 2CzPDBq-III), 7-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 7mDBTPDBq-II), and 6-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 6mDBTPDBq-II), 2-{4-[9,10-di(2-naphthyl)-2-anthryl]phenyl}-1-phenyl-1H-benzimidazole (abbreviation: ZADN), 2-[4'-(9-phenyl-9H-carbazole-3-yl)-3,1'-biphenyl-1-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mpPCBPDBq), and all of these are preferred as host materials.

[0219] Furthermore, among the above organic compounds, specific examples of organic compounds with high electron transport capabilities include pyridine derivatives, diazine derivatives (including pyrimidine derivatives, pyrazine derivatives, and pyridazine derivatives), triazine derivatives, and phlodiazine derivatives, such as 4,6-bis[3-(phenanthrene-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm), 4,6-bis[3-(4-dibenzothienyl)phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-II), and 4,6-bis[3-(9H-carbazole-9-yl)phenyl]pyrimidine (abbreviation: (Abbreviation: 4,6mCzP2Pm), 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol-9-yl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: PCCzPTzn), 9-[3-(4,6-diphenyl-1,3,5-triazin-2-yl)phenyl]-9'-phenyl-2,3'-bi-9H-carbazol (abbreviation: mPCCzPTzn-02), 3,5-bis[3-(9H-carbazol-9-yl)phenyl]pyridine (abbreviation: 35DCzPPy), 1,3,5-tri[3 -(3-pyridyl)phenyl]benzene (abbreviation: TmPyPB), 9,9'-[pyrimidine-4,6-diylbis(biphenyl-3,3'-diyl)]bis(9H-carbazole) (abbreviation: 4,6mCzBP2Pm), 2-[3'-(9,9-dimethyl-9H-fluoren-2-yl)-1,1'-biphenyl-3-yl]-4,6-diphenyl-1,3,5-triazine (abbreviation: mFBPTzn), 8-(1,1'-biphenyl-4-yl)-4-[3-(dibenzothiophen-4-yl)phenyl]-[1]benzofloxacin[3,2-d ]pyrimidine (abbreviation: 8BP-4mDBtPBfpm), 9-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]naphtho[1',2':4,5]flo[2,3-b]pyrazine (abbreviation: 9mDBtBPNfpr), 9-[(3'-dibenzothiophen-4-yl)biphenyl-4-yl]naphtho[1',2':4,5]flo[2,3-b]pyrazine (abbreviation: 9pmDBtBPNfpr), 5-[3-(4,6-diphenyl-1,3,5-triazine-2-yl)phenyl]-7,7-dimethyl-5H,7H-indeno[2,1-b]carbazole (abbreviation: mINc(II)PTzn), 2-[3'-(triphenylene-2-yl)-1,1'-biphenyl-3-yl]-4,6-diphenyl-1,3,5-triazine (abbreviation: mTpBPTzn), 2-[(1,1'-biphenyl)-4-yl]-4-phenyl-6-[9,9'-spirobio(9H-fluoren)-2-yl]-1 ,3,5-triazine (abbreviation: BP-SFTzn), 2,6-bis(4-naphthalene-1-ylphenyl)-4-[4-(3-pyridyl)phenyl]pyrimidine (abbreviation: 2,4NP-6PyPPm), 9-[4-(4,6-diphenyl-1,3,5-triazine-2-yl)-2-dibenzothiophenyl]-2-phenyl-9H-carbazole (abbreviation: PC Examples include organic compounds containing heteroaromatic rings having a diazine ring, such as DBfTzn, 2-[1,1'-biphenyl]-3-yl-4-phenyl-6-(8-[1,1':4',1''-terphenyl]-4-yl-1-dibenzofuranyl)-1,3,5-triazine (abbreviated as mBP-TPDBfTzn), 6-(1,1'-biphenyl-3-yl)-4-[3,5-bis(9H-carbazole-9-yl)phenyl]-2-phenylpyrimidine (abbreviated as 6mBP-4Cz2PPm), and 4-[3,5-bis(9H-carbazole-9-yl)phenyl]-2-phenyl-6-(1,1'-biphenyl-4-yl)pyrimidine (abbreviated as 6BP-4Cz2PPm), all of which are preferred as host materials.

[0220] Furthermore, among the above organic compounds, specific examples of metal complexes that are organic compounds with high electron transport properties include zinc-based or aluminum-based metal complexes such as tris(8-quinolinolato)aluminum(III) (abbreviated as Alq), tris(4-methyl-8-quinolinolato)aluminum(III) (abbreviated as Almq3), bis(10-hydroxybenzo[h]quinolinato)beryllium(II) (abbreviated as BeBq2), bis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum(III) (abbreviated as BAlq), bis(8-quinolinolato)zinc(II) (abbreviated as Znq), and metal complexes having a quinoline ring or a benzoquinoline ring, all of which are preferred as host materials.

[0221] Other polymer compounds such as poly(2,5-pyridinediyl) (abbreviated as PPy), poly[(9,9-dihexylfluorene-2,7-diyl)-co-(pyridine-3,5-diyl)] (abbreviated as PF-Py), and poly[(9,9-dioctylfluorene-2,7-diyl)-co-(2,2'-bipyridine-6,6'-diyl)] (abbreviated as PF-BPy) are also preferred as host materials.

[0222] Furthermore, there are bipolar organic compounds that are highly hole-transporting and highly electron-transporting, such as 9-phenyl-9'-(4-phenyl-2-quinazolinyl)-3,3'-bi-9H-carbazole (abbreviation: PCCzQz), 2-[4'-(9-phenyl-9H-carbazole-3-yl)-3,1'-biphenyl-1-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mpPCBPDBq), and 5-[3-(4,6-diphenyl-1,3,5-triazine-2-yl)phenyl]-7,7-dimethyl-5H,7H-indeno[2,1 Organic compounds having a diazine ring, such as -b]carbazole (abbreviation: mINc(II)PTzn), 11-(4-[1,1'-biphenyl]-4-yl-6-phenyl-1,3,5-triazine-2-yl)-11,12-dihydro-12-phenyl-indoro[2,3-a]carbazole (abbreviation: BP-Icz(II)Tzn), and 7-[4-(9-phenyl-9H-carbazole-2-yl)quinazoline-2-yl]-7H-dibenzo[c,g]carbazole (abbreviation: PC-cgDBCzQz), can also be used as host materials.

[0223] <Electron transport layer> The electron transport layers (114, 114a, 114b) are layers that transport electrons injected from the second electrode 102 or the charge generation layer (106, 106a, 106b) by the electron injection layer (115, 115a, 115b), described later, to the light-emitting layer (113, 113a, 113b, 113c). The electron-transporting material used in the electron transport layers (114, 114a, 114b) has an electron mobility of 1 × 10⁻¹⁰ at an electric field strength [V / cm] square root of 600. -6 cm2 A material having an electron mobility of / Vs or higher is preferred. However, any material with higher electron transport capabilities than hole transport can be used. Furthermore, the electron transport layer (114, 114a, 114b) can function as a single layer, but it may also be a laminated structure of two or more layers. Since the above mixed material has heat resistance, performing the photolithography process on an electron transport layer using this material can suppress the influence of the thermal process on the device characteristics.

[0224] ≪Electron transport material≫ As electron-transporting materials that can be used in the electron transport layers (114, 114a, 114b), organic compounds with high electron transport properties can be used, for example, heteroaromatic compounds can be used. A heteroaromatic compound is a cyclic compound that contains at least two different elements in its ring. The ring structure can include 3-membered rings, 4-membered rings, 5-membered rings, 6-membered rings, etc., but 5-membered rings or 6-membered rings are particularly preferred, and heteroaromatic compounds that contain one or more of the elements carbon, nitrogen, oxygen, or sulfur are preferred. Nitrogen-containing heteroaromatic compounds (nitrogen-containing heteroaromatic compounds) are particularly preferred, and it is preferable to use materials with high electron transport properties (electron-transporting materials) such as nitrogen-containing heteroaromatic compounds or π-electron-deficient heteroaromatic compounds containing them.

[0225] Heteroaromatic compounds are organic compounds that have at least one heteroaromatic ring.

[0226] Furthermore, heteroaromatic rings contain one of the following: a pyridine ring, a diazine ring, a triazine ring, or a polyazole ring, an oxazole ring, or a thiazole ring. Heteroaromatic rings containing a diazine ring include heteroaromatic rings containing a pyrimidine ring, a pyrazine ring, or a pyridazine ring. Heteroaromatic rings containing a polyazole ring include heteroaromatic rings containing an imidazole ring, a triazole ring, or an oxadiazole ring.

[0227] Furthermore, heteroaromatic rings include fused heteroaromatic rings having a fused ring structure. Examples of fused heteroaromatic rings include quinoline rings, benzoquinoline rings, quinoxaline rings, dibenzoquinoxaline rings, quinazoline rings, benzoquinazoline rings, dibenzoquinazoline rings, phenanthroline rings, phlodiazine rings, and benzimidazole rings.

[0228] Examples of heteroaromatic compounds include, among heteroaromatic compounds containing one or more of nitrogen, oxygen, or sulfur in addition to carbon, heteroaromatic compounds having a five-membered ring structure such as heteroaromatic compounds having an imidazole ring, heteroaromatic compounds having a triazole ring, heteroaromatic compounds having an oxazole ring, heteroaromatic compounds having an oxadiazole ring, heteroaromatic compounds having a thiazole ring, and heteroaromatic compounds having a benzimidazole ring.

[0229] Furthermore, among heteroaromatic compounds that contain one or more elements other than carbon, such as nitrogen, oxygen, or sulfur, examples of heteroaromatic compounds having a six-membered ring structure include heteroaromatic compounds having heteroaromatic rings such as pyridine rings, diazine rings (including pyrimidine rings, pyrazine rings, pyridazine rings, etc.), triazine rings, and polyazole rings. Note that while heteroaromatic compounds with a structure in which pyridine rings are linked, examples include heteroaromatic compounds having a bipyridine structure and heteroaromatic compounds having a terpyridine structure.

[0230] Furthermore, examples of heteroaromatic compounds having a fused ring structure that partially includes the above-mentioned six-membered ring structure include heteroaromatic compounds having fused heteroaromatic rings such as quinoline rings, benzoquinoline rings, quinoxaline rings, dibenzoquinoxaline rings, phenanthroline rings, phlodiazine rings (including structures in which an aromatic ring is fused to the furan ring of a phlodiazine ring), and benzimidazole rings.

[0231] Specific examples of heteroaromatic compounds having the above-mentioned five-membered ring structure (polyazole ring (including imidazole ring, triazole ring, oxadiazole ring), oxazole ring, thiazole ring, benzimidazole ring, etc.) include 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviated as PBD), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazole-2-yl]benzene (abbreviated as OXD-7), 9-[4-(5-phenyl-1,3,4-oxadiazole-2-yl)phenyl]-9H-carbazole (abbreviated as CO11), and 3-(4-biphenylyl)-4-phenyl Examples include phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (abbreviated as TAZ), 3-(4-tert-butylphenyl)-4-(4-ethylphenyl)-5-(4-biphenylyl)-1,2,4-triazole (abbreviated as p-EtTAZ), 2,2',2''-(1,3,5-benzenetriyl)tris(1-phenyl-1H-benzimidazole) (abbreviated as TPBI), 2-[3-(dibenzothiophen-4-yl)phenyl]-1-phenyl-1H-benzimidazole (abbreviated as mDBTBIm-II), and 4,4'-bis(5-methylbenzoxazole-2-yl)stilbene (abbreviated as BzOs).

[0232] Specific examples of heteroaromatic compounds having the above-mentioned six-membered ring structure (including heteroaromatic rings having pyridine rings, diazine rings, triazine rings, etc.) include heteroaromatic compounds containing a pyridine ring, such as 3,5-bis[3-(9H-carbazole-9-yl)phenyl]pyridine (abbreviation: 35DCzPPy) and 1,3,5-tri[3-(3-pyridyl)phenyl]benzene (abbreviation: TmPyPB), and 2-{4-[3-(N-phenyl-9H-carbazole-3-yl)-9H-carbazole-9-yl]phenyl}-4,6-diphenyl-1,3,5- Triazine (abbreviation: PCCzPTzn), 9-[3-(4,6-diphenyl-1,3,5-triazine-2-yl)phenyl]-9'-phenyl-2,3'-bi-9H-carbazole (abbreviation: mPCCzPTzn-02), 5-[3-(4,6-diphenyl-1,3,5-triazine-2-yl)phenyl]-7,7-dimethyl-5H,7H-indeno[2,1-b]carbazole (abbreviation: mINc(II)PTzn), 2-[3'-(triphenylene-2-yl)-1,1'-biphenyl-3-yl]-4,6-diphenyl-1,3,5-triazine ( (Abbreviation: mTpBPTzn), 2-[(1,1'-biphenyl)-4-yl]-4-phenyl-6-[9,9'-spirobi(9H-fluorene)-2-yl]-1,3,5-triazine (Abbreviation: BP-SFTzn), 2,6-bis(4-naphthalene-1-ylphenyl)-4-[4-(3-pyridyl)phenyl]pyrimidine (Abbreviation: 2,4NP-6PyPPm), 9-[4-(4,6-diphenyl-1,3,5-triazine-2-yl)-2-dibenzothiophenyl]-2-phenyl-9H-carbazole (Abbreviation: PCDBfTzn), 2-[1,1'-bi Heteroaromatic compounds containing heteroaromatic rings having a triazine ring, such as phenyl]-3-yl-4-phenyl-6-(8-[1,1':4',1''-terphenyl]-4-yl-1-dibenzofuranyl)-1,3,5-triazine (abbreviation: mBP-TPDBfTzn), 2-{3-[3-(dibenzothiophen-4-yl)phenyl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: mDBtBPTzn), mFBPTzn, 4,6-bis[3-(phenanthrene-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm), 4,6-Bis[3-(4-dibenzothienyl)phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-II), 4,6-Bis[3-(9H-carbazole-9-yl)phenyl]pyrimidine (abbreviation: 4,6mCzP2Pm), 4,6mCzBP2Pm, 6-(1,1'-biphenyl-3-yl)-4-[3,5-bis(9H-carbazole-9-yl)phenyl]-2-phenylpyrimidine (abbreviation: 6mBP-4Cz2 PPm), 4-[3,5-bis(9H-carbazole-9-yl)phenyl]-2-phenyl-6-(1,1'-biphenyl-4-yl)pyrimidine (abbreviation: 6BP-4Cz2PPm), 4-[3-(dibenzothiophen-4-yl)phenyl]-8-(naphthalene-2-yl)-[1]benzoflo[3,2-d]pyrimidine (abbreviation: 8βN-4mDBtPBfpm), 8BP-4mDBtPBfpm, 9mDBtBP Nfpr, 9pmDBtBPNfpr, 3,8-bis[3-(dibenzothiophen-4-yl)phenyl]benzoflo[2,3-b]pyrazine (abbreviation: 3,8mDBtP2Bfpr), 4,8-bis[3-(dibenzothiophen-4-yl)phenyl]-[1]benzoflo[3,2-d]pyrimidine (abbreviation: 4,8mDBtP2Bfpm), 8-[3'-(dibenzothiophen-4-yl)(1,1'-biphenyl- Examples include heteroaromatic compounds containing a heteroaromatic ring having a diazine (pyrimidine) ring, such as 3-yl)naphtho[1',2':4,5]flo[3,2-d]pyrimidine (abbreviation: 8mDBtBPNfpm) and 8-[(2,2'-binaphthalene)-6-yl]-4-[3-(dibenzothiophen-4-yl)phenyl]-[1]benzoflo[3,2-d]pyrimidine (abbreviation: 8(βN2)-4mDBtPBfpm). Note that the above aromatic compounds containing heteroaromatic rings include heteroaromatic compounds having condensed heteroaromatic rings.

[0233] Other examples include 2,2'-(pyridine-2,6-diyl)bis(4-phenylbenzo[h]quinazoline) (abbreviation: 2,6(P-Bqn)2Py), 2,2'-(2,2'-bipyridine-6,6'-diyl)bis(4-phenylbenzo[h]quinazoline) (abbreviation: 6,6'(P-Bqn)2BPy), 2,2'-(pyridine-2,6-diyl)bis{4-[4-(2-naphthyl)phenyl]-6-phenylpyrimidine} (abbreviation: 2,6(NP-PPm)2Py), 6-(1,1'-biphenyl-3-yl)-4-[3,5-bis(9H-carbazole-9-yl)phenyl]-2-phenylpyrimidine (abbreviation: Examples include heteroaromatic compounds containing heteroaromatic rings having a diazine (pyrimidine) ring, such as 6mBP-4Cz2PPm, and heteroaromatic compounds containing heteroaromatic rings having a triazine ring, such as 2,4,6-tris(3'-(pyridin-3-yl)biphenyl-3-yl)-1,3,5-triazine (abbreviation: TmPPPyTz), 2,4,6-tris(2-pyridyl)-1,3,5-triazine (abbreviation: 2Py3Tz), and 2-[3-(2,6-dimethyl-3-pyridyl)-5-(9-phenanthryl)phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviation: mPn-mDMePyPTzn).

[0234] Specific examples of heteroaromatic compounds having a fused ring structure that partially includes a 6-membered ring structure (heteroaromatic compounds having a fused ring structure) include vasophenanthroline (abbreviation: Bphen), vasocuproin (abbreviation: BCP), 2,9-di(naphthalene-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBphen), 2,2-(1,3-phenylene)bis[9-phenyl-1,10-phenanthroline] (abbreviation: mPPhen2P), 2,2'-(pyridine-2,6-diyl)bis(4-phenylbenzo[h]quinazoline) (abbreviation: 2,6(P-Bqn)2Py), 2-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTPDBq-II), and 2-[3'-(dibenzothiophen-4-yl) [biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II), 2-[3'-(9H-carbazol-9-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mCzBPDBq), 2-[4-(3,6-diphenyl-9H-carbazol-9-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2CzPD Examples include heteroaromatic compounds having a quinoxaline ring, such as Bq-III), 7-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 7mDBTPDBq-II), and 6-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 6mDBTPDBq-II), 2mpPCBPDBq, etc.

[0235] In addition to the heteroaromatic compounds shown above, the following metal complexes can be used in the electron transport layers (114, 114a, 114b). Examples include metal complexes having a quinoline ring or benzoquinoline ring, such as tris(8-quinolinolato)aluminum(III) (abbreviated as Alq3), Almq3, 8-quinolinolatritium(I) (abbreviated as Liq), BeBq2, bis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum(III) (abbreviated as BAlq), and bis(8-quinolinolato)zinc(II) (abbreviated as Znq); and metal complexes having an oxazole ring or thiazole ring, such as bis[2-(2-benzoxazollyl)phenolato]zinc(II) (abbreviated as ZnPBO) and bis[2-(2-benzothiazolyl)phenolato]zinc(II) (abbreviated as ZnBTZ).

[0236] Furthermore, polymer compounds such as poly(2,5-pyridinediyl) (abbreviated as PPy), poly[(9,9-dihexylfluorene-2,7-diyl)-co-(pyridine-3,5-diyl)] (abbreviated as PF-Py), and poly[(9,9-dioctylfluorene-2,7-diyl)-co-(2,2'-bipyridine-6,6'-diyl)] (abbreviated as PF-BPy) can also be used as electron transport materials.

[0237] Furthermore, the electron transport layers (114, 114a, 114b) may be not only single layers, but also have a structure in which two or more layers made of the above material are stacked.

[0238] <Electron injection layer> The electron injection layers (115, 115a, 115b) are layers containing a material with high electron injection capabilities. Furthermore, the electron injection layers (115, 115a, 115b) are layers for increasing the electron injection efficiency from the second electrode 102, and it is preferable to use a material in which the difference between the work function value of the material used for the second electrode 102 and the LUMO level value of the material used for the electron injection layers (115, 115a, 115b) is small (0.5 eV or less). Therefore, the electron injection layer 115 contains lithium, cesium, lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF2), 8-(quinolinolato)lithium (abbreviated as Liq), 2-(2-pyridyl)phenolate (abbreviated as LiPP), 2-(2-pyridyl)-3-pyridinolatritium (abbreviated as LiPPy), 4-phenyl-2-(2-pyridyl)phenolate (abbreviated as LiPPP), and lithium oxide (LiO x Alkali metals such as cesium carbonate, alkaline earth metals, or compounds thereof can be used. Rare earth metal compounds such as erbium fluoride (ErF3) and ytterbium (Yb) can also be used. The electron injection layers (115, 115a, 115b) may be formed by mixing multiple types of the above materials, or by stacking multiple types of the above materials. Electrides may also be used in the electron injection layers (115, 115a, 115b). Examples of electrides include substances obtained by adding a high concentration of electrons to a mixed oxide of calcium and aluminum. The materials that constitute the electron transport layers (114, 114a, 114b) described above can also be used.

[0239] Furthermore, a mixed material comprising an organic compound and an electron donor may be used in the electron injection layers (115, 115a, 115b). Such a mixed material exhibits excellent electron injection and electron transport properties because electrons are generated in the organic compound by the electron donor. In this case, the organic compound is preferably a material with excellent electron transport properties. Specifically, for example, an electron transport material (metal complex or heteroaromatic compound, etc.) used in the electron transport layers (114, 114a, 114b) described above can be used. The electron donor can be any substance that exhibits electron-donating properties to the organic compound. Specifically, alkali metals, alkaline earth metals, and rare earth metals are preferred, such as lithium, cesium, magnesium, calcium, erbium, and ytterbium. Alkali metal oxides and alkaline earth metal oxides are also preferred, such as lithium oxide, calcium oxide, and barium oxide. Lewis bases such as magnesium oxide can also be used. Furthermore, organic compounds such as tetrathiafulvalene (abbreviated as TTF) can also be used. Furthermore, multiple layers of these materials may be used.

[0240] In addition, a mixed material consisting of an organic compound and a metal may be used for the electron injection layers (115, 115a, 115b). The organic compound used here preferably has a LUMO level of -3.6 eV or higher and -2.3 eV or lower. Furthermore, a material having lone pairs of electrons is preferred.

[0241] Therefore, as the organic compound used in the above-mentioned mixed material, a mixed material obtained by mixing a heteroaromatic compound with a metal, as described above for use in an electron transport layer, may be used. Preferred heteroaromatic compounds include materials having lone pairs of electrons, such as heteroaromatic compounds having a 5-membered ring structure (imidazole ring, triazole ring, oxazole ring, oxadiazole ring, thiazole ring, benzimidazole ring, etc.), heteroaromatic compounds having a 6-membered ring structure (pyridine ring, diazine ring (including pyrimidine ring, pyrazine ring, pyridazine ring, etc.), triazine ring, bipyridine ring, terpyridine ring, etc.), and heteroaromatic compounds having a fused ring structure that partially includes a 6-membered ring structure (quinoline ring, benzoquinoline ring, quinoxaline ring, dibenzoquinoxaline ring, phenanthroline ring, etc.). Specific materials have been described above, so further explanation is omitted here.

[0242] Furthermore, it is preferable to use transition metals belonging to Group 5, Group 7, Group 9, or Group 11 of the periodic table, or materials belonging to Group 13, as the metals used in the above-mentioned mixed material. Examples include Ag, Cu, Al, or In. In this case, the organic compound forms a partially occupied molecular orbital (SOMO) with the transition metal.

[0243] For example, when amplifying the light obtained from the light-emitting layer 113b, it is preferable to form the optical distance between the second electrode 102 and the light-emitting layer 113b to be less than 1 / 4 of the wavelength λ of the light emitted by the light-emitting layer 113b. In this case, this can be adjusted by changing the film thickness of the electron transport layer 114b or the electron injection layer 115b.

[0244] Furthermore, as shown in the light-emitting device in Figure 1(D), by providing a charge generation layer 106 between two EL layers (103a, 103b), a structure in which multiple EL layers are stacked between a pair of electrodes (also called a tandem structure) can be created.

[0245] <Charge generation layer> The charge generation layer 106 has the function of injecting electrons into the EL layer 103a and holes into the EL layer 103b when a voltage is applied between the first electrode (anode) 101 and the second electrode (cathode) 102. The charge generation layer 106 may be a configuration in which an electron acceptor is added to a hole transport material (also called a P-type layer), or a configuration in which an electron donor is added to an electron transport material (also called an electron injection buffer layer). Furthermore, both of these configurations may be stacked. In addition, an electron relay layer may be provided between the P-type layer and the electron injection buffer layer. By forming the charge generation layer 106 using the materials described above, it is possible to suppress the increase in driving voltage when the EL layers are stacked.

[0246] In the charge generation layer 106, when an electron acceptor is added to a hole-transporting material which is an organic compound (P-type layer), the material shown in this embodiment can be used as the hole-transporting material. Examples of electron acceptors include 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviated as F4-TCNQ), chloranil, etc. Other examples include oxides of metals belonging to groups 4 to 8 of the periodic table. Specifically, examples include vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, molybdenum oxide, tungsten oxide, manganese oxide, and rhenium oxide. The acceptor material described above may also be used. Furthermore, the P-type layer may be used as a mixed film by mixing the materials, or as single films containing each material stacked together.

[0247] Furthermore, in the charge generation layer 106, if an electron donor is added to the electron transport material (electron injection buffer layer), the materials shown in this embodiment can be used as the electron transport material. As the electron donor, alkali metals, alkaline earth metals, rare earth metals, or metals belonging to groups 2 and 13 of the periodic table, as well as their oxides and carbonates, can be used. Specifically, lithium (Li), cesium (Cs), magnesium (Mg), calcium (Ca), ytterbium (Yb), indium (In), lithium oxide (Li2O), cesium carbonate, etc., are preferred. Organic compounds such as tetrathianaphthalene may also be used as electron donors.

[0248] In the charge generation layer 106, when an electron relay layer is provided between the P-type layer and the electron injection buffer layer, the electron relay layer contains at least an electron-transporting material and has the function of preventing interaction between the electron injection buffer layer and the P-type layer and smoothly transferring electrons. Preferably, the LUMO level of the electron-transporting material included in the electron relay layer is between the LUMO level of the acceptor material in the P-type layer and the LUMO level of the electron-transporting material included in the electron transport layer in contact with the charge generation layer 106. The specific energy level of the LUMO level of the electron-transporting material used in the electron relay layer is preferably -5.0 eV or higher, more preferably -5.0 eV or higher and -3.0 eV or lower. Preferably, as the electron-transporting material used in the electron relay layer, a phthalocyanine-based material or a metal complex having a metal-oxygen bond and an aromatic ligand is used.

[0249] Although Figure 1(D) shows a configuration in which two EL layers 103 are stacked, a stacked structure of three or more EL layers may be used by providing a charge generation layer between different EL layers.

[0250] <Circuit board> The light-emitting device shown in this embodiment can be formed on various substrates. The type of substrate is not limited to any particular type. Examples of substrates include semiconductor substrates (e.g., single crystal substrates or silicon substrates), SOI substrates, glass substrates, quartz substrates, plastic substrates, metal substrates, stainless steel substrates, substrates with stainless steel foil, tungsten substrates, substrates with tungsten foil, flexible substrates, laminated films, paper containing fibrous materials, or base films.

[0251] Examples of glass substrates include barium borosilicate glass, aluminobrosilicate glass, or soda-lime glass. Examples of flexible substrates, laminated films, and base films include plastics such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polyethersulfone (PES), synthetic resins such as acrylic, polypropylene, polyester, polyvinyl fluoride, or polyvinyl chloride, polyamide, polyimide, aramid, epoxy resin, inorganic vapor-deposited film, or paper.

[0252] In this embodiment, the light-emitting device can be fabricated using vapor-phase methods such as vapor deposition, or liquid-phase methods such as spin coating or inkjet printing. When using vapor deposition, physical vapor deposition (PVD) methods such as sputtering, ion plating, ion beam deposition, molecular beam deposition, or vacuum deposition, or chemical vapor deposition (CVD) methods can be used. In particular, the various functional layers included in the EL layer of the light-emitting device (hole injection layer 111, hole transport layer 112, light-emitting layer 113, electron transport layer 114, electron injection layer 115) can be formed by methods such as vapor deposition (vacuum deposition, etc.), coating (dip coating, die coating, bar coating, spin coating, spray coating, etc.), and printing (inkjet, screen printing, offset printing, flexographic printing, gravure printing, microcontact printing, etc.).

[0253] Furthermore, when applying the above-mentioned coating method, printing method, or other film formation method, polymer compounds (oligomers, dendrimers, polymers, etc.), medium-molecular-weight compounds (compounds in the intermediate region between low-molecular-weight and high-molecular-weight compounds: molecular weight 400 to 4000), inorganic compounds (quantum dot materials, etc.) can be used. As for quantum dot materials, colloidal quantum dot materials, alloy-type quantum dot materials, core-shell type quantum dot materials, core-type quantum dot materials, etc., can be used.

[0254] The layers constituting the EL layer 103 of the light-emitting device shown in this embodiment (hole injection layer 111, hole transport layer 112, light-emitting layer 113, electron transport layer 114, electron injection layer 115) are not limited to the materials shown in this embodiment, and other materials can be used in combination as long as they can satisfy the function of each layer.

[0255] In this specification, the terms "layer" and "film" may be used interchangeably as appropriate.

[0256] The configuration shown in this embodiment can be used in appropriate combination with the configurations shown in other embodiments.

[0257] (Embodiment 3) This embodiment describes a specific configuration example and manufacturing method of a light-emitting device (also called a display panel) which is one aspect of the present invention.

[0258] <Example of configuration of light-emitting device 700 1> The light-emitting device 700 shown in Figure 2(A) includes light-emitting devices 550B, 550G, 550R, and a partition wall 528. The light-emitting devices 550B, 550G, 550R, and the partition wall 528 are formed on a functional layer 520 provided on a first substrate 510. The functional layer 520 includes drive circuits GD and SD, composed of multiple transistors, as well as wiring for their electrical connection. These drive circuits are, for example, electrically connected to the light-emitting devices 550B, 550G, and 550R, respectively, and can drive them. Furthermore, the light-emitting device 700 includes an insulating layer 705 on the functional layer 520, light-emitting devices 550B, 550G, 550R, and the partition wall 528, and the insulating layer 705 has the function of bonding the functional layer 520 to the second substrate 770. Furthermore, the drive circuits GD and SD will be described later in Embodiment 4.

[0259] Furthermore, the light-emitting devices 550B, 550G, and 550R have the device structure shown in Embodiment 2. That is, this shows the case where the EL layer 103 in the structure shown in Figure 1(A) differs for each light-emitting device.

[0260] In this specification, a structure in which different light-emitting layers are created or painted using light-emitting devices of each color (e.g., blue (B), green (G), and red (R)) may be referred to as an SBS (Side By Side) structure. In the light-emitting device 700 shown in Figure 2(A), light-emitting devices 550B, 550G, and 550R are arranged in this order, but one aspect of the present invention is not limited to this configuration. For example, in the light-emitting device 700, these light-emitting devices may be arranged in the order of light-emitting device 550R, light-emitting device 550G, and light-emitting device 550B.

[0261] As shown in Figure 2(A), the light-emitting device 550B has an electrode 551B, an electrode 552, and an EL layer 103B. The specific configuration of each layer is as shown in Embodiment 2. The EL layer 103B has a laminated structure consisting of multiple layers with different functions, including the light-emitting layer. In Figure 2(A), only the hole injection / transport layer 104B, the electron transport layer 108B, and the electron injection layer 109 are shown among the layers included in the EL layer 103B, which includes the light-emitting layer, but the present invention is not limited to these. The hole injection / transport layer 104B refers to a layer having the functions of a hole injection layer and a hole transport layer as shown in Embodiment 2, and may have a laminated structure. In this specification, the hole injection / transport layer can be interpreted in this way in any light-emitting device.

[0262] Furthermore, the electron transport layer 108B may have a function to block holes moving from the anode side through the light-emitting layer to the cathode side. Also, the electron injection layer 109 may have a laminated structure formed using some or all different materials.

[0263] Furthermore, as shown in Figure 2(A), insulating layers 107B may be formed on the sides (or edges) of the layers included in the EL layer 103B, which includes the light-emitting layer: the hole injection / transport layer 104B, the light-emitting layer, and the electron transport layer 108B. The insulating layer 107B is formed in contact with the sides (or edges) of the EL layer 103B. This suppresses the penetration of oxygen, moisture, or their constituent elements into the interior from the sides of the EL layer 103B. For example, aluminum oxide, magnesium oxide, hafnium oxide, gallium oxide, indium gallium zinc oxide, silicon nitride, or silicon nitride oxide can be used for the insulating layer 107B. The insulating layer 107B may also be formed by laminating the aforementioned materials. Sputtering, CVD, MBE, PLD, ALD, etc., can be used to form the insulating layer 107B, but the ALD method, which has good coverage, is more preferable.

[0264] Furthermore, an electron injection layer 109 is formed covering a portion of the EL layer 103B (including the light-emitting layer, the hole injection / transport layer 104B, and the electron transport layer 108B) and the insulating layer 107B. The electron injection layer 109 may also be a laminated structure of two or more layers with different electrical resistances within the layers.

[0265] Furthermore, electrode 552 is formed on the electron injection layer 109. Electrode 551B and electrode 552 have overlapping regions. Additionally, an EL layer 103B is present between electrode 551B and electrode 552.

[0266] Furthermore, the EL layer 103B shown in Figure 2(A) has the same configuration as the EL layer 103 described in Embodiment 2. In addition, the EL layer 103B can emit, for example, blue light.

[0267] As shown in Figure 2(A), the light-emitting device 550G has an electrode 551G, an electrode 552, and an EL layer 103G. The specific configuration of each layer is as shown in Embodiment 2. The EL layer 103G has a laminated structure consisting of multiple layers with different functions, including the light-emitting layer. In Figure 2(A), only the hole injection / transport layer 104G, the electron transport layer 108G, and the electron injection layer 109 are shown among the layers included in the EL layer 103G, which includes the light-emitting layer, but the present invention is not limited to these. The hole injection / transport layer 104G refers to a layer having the functions of a hole injection layer and a hole transport layer as shown in Embodiment 2, and may have a laminated structure.

[0268] Furthermore, the electron transport layer 108G may have a function to block holes moving from the anode side through the light-emitting layer to the cathode side. Also, the electron injection layer 109 may have a laminated structure formed using some or all different materials.

[0269] Furthermore, as shown in Figure 2(A), insulating layers 107G may be formed on the sides (or edges) of the layers included in the EL layer 103G, which includes the light-emitting layer: the hole injection / transport layer 104G, the light-emitting layer, and the electron transport layer 108G. The insulating layer 107G is formed in contact with the sides (or edges) of the EL layer 103G. This suppresses the penetration of oxygen, moisture, or their constituent elements into the interior from the sides of the EL layer 103G. For example, aluminum oxide, magnesium oxide, hafnium oxide, gallium oxide, indium gallium zinc oxide, silicon nitride, or silicon nitride oxide can be used for the insulating layer 107G. The insulating layer 107G may also be formed by laminating the aforementioned materials. Sputtering, CVD, MBE, PLD, ALD, etc., can be used to form the insulating layer 107G, but the ALD method, which has good coverage, is more preferable.

[0270] Furthermore, an electron injection layer 109 is formed covering a portion of the EL layer 103G (including the light-emitting layer, the hole injection / transport layer 104G, and the electron transport layer 108G) and the insulating layer 107G. The electron injection layer 109 may also be a laminated structure of two or more layers with different electrical resistances within the layers.

[0271] Furthermore, electrode 552 is formed on the electron injection layer 109. Electrode 551G and electrode 552 have overlapping regions. Additionally, an EL layer 103G is present between electrode 551G and electrode 552.

[0272] Furthermore, the EL layer 103G shown in Figure 2(A) has the same configuration as the EL layer 103 described in Embodiment 2. In addition, the EL layer 103G can emit, for example, green light.

[0273] As shown in Figure 2(A), the light-emitting device 550R has an electrode 551R, an electrode 552, and an EL layer 103R. The specific configuration of each layer is as shown in Embodiment 2. The EL layer 103R has a laminated structure consisting of multiple layers with different functions, including the light-emitting layer. In Figure 2(A), only the hole injection / transport layer 104R, the electron transport layer 108R, and the electron injection layer 109 are shown among the layers included in the EL layer 103R, which includes the light-emitting layer, but the present invention is not limited to these. The hole injection / transport layer 104R refers to a layer having the functions of a hole injection layer and a hole transport layer as shown in Embodiment 2, and may have a laminated structure.

[0274] Furthermore, the electron transport layer 108R may have a function to block holes that move from the anode side through the light-emitting layer to the cathode side. Also, the electron injection layer 109 may have a laminated structure formed using some or all different materials.

[0275] Furthermore, as shown in Figure 2(A), insulating layers 107R may be formed on the sides (or edges) of the layers included in the EL layer 103R, which includes the light-emitting layer: the hole injection / transport layer 104R, the light-emitting layer, and the electron transport layer 108R. The insulating layer 107R is formed in contact with the sides (or edges) of the EL layer 103R. This suppresses the penetration of oxygen, moisture, or their constituent elements into the interior from the sides of the EL layer 103R. For example, aluminum oxide, magnesium oxide, hafnium oxide, gallium oxide, indium gallium zinc oxide, silicon nitride, or silicon nitride oxide can be used for the insulating layer 107R. The insulating layer 107R may also be formed by laminating the aforementioned materials. Sputtering, CVD, MBE, PLD, ALD, etc., can be used to form the insulating layer 107R, but the ALD method, which has good coverage, is more preferable.

[0276] Furthermore, an electron injection layer 109 is formed covering a portion of the EL layer 103R (including the light-emitting layer, the hole injection / transport layer 104R, and the electron transport layer 108R) and the insulating layer 107R. The electron injection layer 109 may also be a laminated structure of two or more layers with different electrical resistances within the layers.

[0277] Furthermore, electrode 552 is formed on the electron injection layer 109. Electrode 551R and electrode 552 have overlapping regions. Additionally, an EL layer 103R is present between electrode 551R and electrode 552.

[0278] Furthermore, the EL layer 103R shown in Figure 2(A) has the same configuration as the EL layer 103 described in Embodiment 2. In addition, the EL layer 103R can emit, for example, red light.

[0279] There is a partition wall 528 between each of the EL layers 103B, 103G, and 103R. As shown in Figure 2(A), the EL layers (EL layers 103B, 103G, and 103R) of each light-emitting device and the partition wall 528 are in contact at the sides (or ends) via insulating layers (107B, 107G, and 107R).

[0280] In each EL layer, the hole injection layer, particularly the hole transport region located between the anode and the light-emitting layer, often has high conductivity. Therefore, if it is formed as a common layer for adjacent light-emitting devices, it can cause crosstalk. Accordingly, as shown in this example configuration, by providing a partition wall 528 made of insulating material between each EL layer, it is possible to suppress the occurrence of crosstalk between adjacent light-emitting devices.

[0281] Furthermore, in the manufacturing method described in this embodiment, the side (or edge) of the EL layer is exposed during the patterning process. As a result, the EL layer is more susceptible to deterioration due to the intrusion of oxygen and water from the side (or edge) of the EL layer. Therefore, by providing the partition wall 528, it is possible to suppress the deterioration of the EL layer during the manufacturing process.

[0282] Furthermore, by providing the partition wall 528, it is possible to flatten the recess formed between adjacent light-emitting devices. Flattening the recess helps to suppress disconnection of the electrodes 552 formed on each EL layer. As the insulating material used to form the partition wall 528, organic materials such as acrylic resin, polyimide resin, epoxy resin, imide resin, polyamide resin, polyimidoamide resin, silicone resin, siloxane resin, benzocyclobutene resin, phenol resin, and precursors of these resins can be used. Alternatively, organic materials such as polyvinyl alcohol (PVA), polyvinyl butyral, polyvinylpyrrolidone, polyethylene glycol, polyglycerin, pullulan, water-soluble cellulose, or alcohol-soluble polyamide resin may be used. Photosensitive resins such as photoresists can also be used. The photosensitive resin can be either a positive-type or negative-type material.

[0283] Furthermore, the difference between the height of the upper surface of the partition wall 528 and the height of the upper surface of any of the EL layers 103B, EL layer 103G, and EL layer 103R is preferably 0.5 times or less the thickness of the partition wall 528, and more preferably 0.3 times or less. Also, for example, the partition wall 528 may be provided such that the upper surface of any of the EL layers 103B, EL layer 103G, and EL layer 103R is higher than the upper surface of the partition wall 528. Also, for example, the partition wall 528 may be provided such that the upper surface of the partition wall 528 is higher than the upper surface of the light-emitting layer of the EL layer 103B, EL layer 103G, and EL layer 103R.

[0284] In a high-resolution light-emitting device (display panel) with a resolution exceeding 1000 ppi, if electrical conductivity is detected between the EL layer 103B, EL layer 103G, and EL layer 103R, a crosstalk phenomenon occurs, narrowing the color gamut that the light-emitting device can display. By providing a partition wall 528 in a high-resolution display panel exceeding 1000 ppi, preferably a high-resolution display panel exceeding 2000 ppi, and more preferably an ultra-high-resolution display panel exceeding 5000 ppi, a display panel capable of displaying vivid colors can be provided.

[0285] Figure 2(B) shows a schematic top view of the light-emitting device 700 corresponding to the dashed line Ya-Yb in the cross-sectional view of Figure 2(A). Figure 2(B) shows a so-called stripe arrangement in which light-emitting devices of the same color are arranged in the Y direction. In addition, light-emitting devices of the same color are arranged in the X direction, which intersects with the Y direction. That is, light-emitting devices 550B, 550G, and 550R are each arranged in a matrix. The arrangement method of the light-emitting devices is not limited to this, and arrangement methods such as delta arrangement and zigzag arrangement may be applied, or pentile arrangement and diamond arrangement may be used.

[0286] Furthermore, since the separation process of each EL layer (EL layer 103B, EL layer 103G, and EL layer 103R) is performed using photolithography to form patterns, a high-definition light-emitting device (display panel) can be manufactured. In addition, the edges (sides) of the EL layers processed by pattern formation using photolithography have a shape that is substantially the same surface (or substantially located on the same plane). At this time, the width (SE) of the gap 580 between each EL layer is preferably 5 μm or less, and more preferably 1 μm or less.

[0287] In EL layers, the hole injection layer, particularly the hole transport region located between the anode and the light-emitting layer, often has high conductivity. Therefore, if it is formed as a common layer for adjacent light-emitting devices, it can cause crosstalk. Consequently, by separating the EL layer using a pattern formation method with photolithography, as shown in this example, it is possible to suppress the occurrence of crosstalk between adjacent light-emitting devices.

[0288] Furthermore, Figure 2(C) is a schematic cross-sectional view corresponding to the dashed line C1-C2 in Figure 2(B). Figure 2(C) shows the connection portion 130 where the connecting electrode 551C and electrode 552 are electrically connected. At the connection portion 130, electrode 552 is provided in contact with the connecting electrode 551C. In addition, a partition wall 528 is provided covering the end of the connecting electrode 551C.

[0289] <Example 1 of a manufacturing method for a light-emitting device> As shown in Figure 3(A), electrodes 551B, 551G, and 551R are formed. For example, a conductive film is formed on a functional layer 520 formed on the first substrate 510, and then processed into a predetermined shape using photolithography.

[0290] Conductive films can be formed using methods such as sputtering, chemical vapor deposition (CVD), molecular beam epitaxy (MBE), vacuum deposition, pulsed laser deposition (PLD), and atomic layer deposition (ALD). CVD methods include plasma-enhanced CVD (PECVD) and thermal CVD. One type of thermal CVD is metal-organic CVD (MOCVD).

[0291] In addition to the photolithography method described above, conductive films may also be processed using nanoimprint lithography, sandblasting, lift-off methods, etc. Island-like thin films may also be directly formed using a film deposition method that utilizes a shielding mask such as a metal mask.

[0292] There are two main methods for processing using photolithography. One method involves forming a resist mask on the thin film to be processed, processing the thin film by etching or other means, and then removing the resist mask. The other method involves forming a photosensitive thin film, then exposing and developing it to process the thin film into the desired shape. In the former method, there are heat treatment steps such as heating after resist coating (PAB: Pre-Applied Bake) and heating after exposure (PEB: Post-Exposure Bake). In one aspect of the present invention, lithography is used not only for processing conductive films but also for processing thin films (films made of organic compounds, or films containing organic compounds in part) used to form EL layers.

[0293] In photolithography, the light used for exposure can be, for example, i-line (wavelength 365 nm), g-line (wavelength 436 nm), h-line (wavelength 405 nm), or a mixture thereof. Other options include ultraviolet light, KrF laser light, or ArF laser light. Exposure may also be performed using immersion lithography. Furthermore, extreme ultraviolet (EUV) light or X-rays may be used as the light source for exposure. An electron beam can also be used instead of light for exposure. Using extreme ultraviolet light, X-rays, or an electron beam is preferable because it allows for extremely fine processing. Note that a photomask is not required when exposure is performed by scanning a beam such as an electron beam.

[0294] For etching thin films using a resist mask, methods such as dry etching, wet etching, and sandblasting can be used.

[0295] Next, as shown in Figure 3(B), an EL layer 103B is formed on electrodes 551B, 551G, and 551R. In Figure 3(B), the hole injection / transport layer 104B, the light-emitting layer, and the electron transport layer 108B, which are included in the EL layer 103B, are formed. For example, the EL layer 103B is formed on electrodes 551B, 551G, and 551R using a vacuum deposition method, so as to cover them. Furthermore, a sacrificial layer 110B is formed on the EL layer 103B.

[0296] The sacrificial layer 110B can be a film with high resistance to etching of the EL layer 103B, i.e., a film with a high etching selectivity ratio. Furthermore, it is preferable that the sacrificial layer 110B has a laminated structure of a first sacrificial layer and a second sacrificial layer with different etching selectivity ratios. Additionally, the sacrificial layer 110B can be a film that can be removed by a wet etching method that causes minimal damage to the EL layer 103B. Oxalic acid can be used as the etching material for wet etching. In this specification, the sacrificial layer may also be referred to as the mask layer.

[0297] As the sacrificial layer 110B, for example, an inorganic film such as a metal film, alloy film, metal oxide film, semiconductor film, or inorganic insulating film can be used. Furthermore, the sacrificial layer 110B can be formed by various film deposition methods such as sputtering, vapor deposition, CVD, and ALD.

[0298] As the sacrificial layer 110B, metal materials such as gold, silver, platinum, magnesium, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper, palladium, titanium, aluminum, yttrium, zirconium, and tantalum, or alloy materials containing such metal materials, can be used. In particular, it is preferable to use low-melting-point materials such as aluminum or silver.

[0299] Furthermore, metal oxides such as indium gallium zinc oxide (In-Ga-Zn oxide, also written as IGZO) can be used as the sacrificial layer 110B. In addition, indium oxide, indium zinc oxide (In-Zn oxide), indium tin oxide (In-Sn oxide), indium titanium oxide (In-Ti oxide), indium tin zinc oxide (In-Sn-Zn oxide), indium titanium zinc oxide (In-Ti-Zn oxide), indium gallium tin zinc oxide (In-Ga-Sn-Zn oxide), etc. can be used. Alternatively, indium tin oxide containing silicon can also be used.

[0300] Furthermore, element M (where M is one or more selected from aluminum, silicon, boron, yttrium, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, or magnesium) may be used instead of gallium. In particular, it is preferable that M be one or more selected from gallium, aluminum, or yttrium.

[0301] Furthermore, inorganic insulating materials such as aluminum oxide, hafnium oxide, and silicon oxide can be used as the sacrificial layer 110B.

[0302] Furthermore, it is preferable to use a material that is soluble in a solvent that does not chemically affect at least the film located at the top of the EL layer 103B (electron transport layer 108B) as the sacrificial layer 110B. In particular, a material soluble in water or alcohol can be suitably used for the sacrificial layer 110B. When forming the sacrificial layer 110B, it is preferable to coat it using a wet deposition method while dissolved in a solvent such as water or alcohol, and then perform a heat treatment to evaporate the solvent. At this time, performing the heat treatment under a reduced pressure atmosphere is preferable because it allows the solvent to be removed at a low temperature and in a short time, thereby reducing thermal damage to the EL layer 103B.

[0303] Furthermore, when the sacrificial layer 110B is to be made into a laminated structure, the layer formed from the above-mentioned material can be designated as the first sacrificial layer, and a second sacrificial layer can be formed on top of it to create a laminated structure.

[0304] In this case, the second sacrificial layer is a film used as a hard mask when etching the first sacrificial layer. Furthermore, the first sacrificial layer is exposed during processing of the second sacrificial layer. Therefore, the first and second sacrificial layers are selected based on a combination of films with a high etching selectivity ratio. Thus, the film that can be used for the second sacrificial layer can be selected according to the etching conditions of the first and second sacrificial layers.

[0305] For example, when dry etching using a fluorine-containing gas (also called a fluorine-based gas) is used for etching the second sacrificial layer, silicon, silicon nitride, silicon oxide, tungsten, titanium, molybdenum, tantalum, tantalum nitride, alloys containing molybdenum and niobium, or alloys containing molybdenum and tungsten can be used for the second sacrificial layer. Here, metal oxide films such as IGZO and ITO can be used for the first sacrificial layer as films that allow for a higher selectivity ratio for etching (i.e., a slower etching rate) compared to dry etching using the above-mentioned fluorine-based gas.

[0306] However, the second sacrificial layer can be selected from a variety of materials, depending on the etching conditions of the first sacrificial layer and the etching conditions of the second sacrificial layer. For example, it can be selected from among the films that can be used for the first sacrificial layer.

[0307] Furthermore, a nitride film can be used as the second sacrificial layer. Specifically, nitrides such as silicon nitride, aluminum nitride, hafnium nitride, titanium nitride, tantalum nitride, tungsten nitride, gallium nitride, and germanium nitride can be used.

[0308] Alternatively, an oxide film can be used as the second sacrificial layer. Typically, oxide films or oxynitride films such as silicon oxide, silicon oxynitride, aluminum oxide, aluminum oxynitride, hafnium oxide, and hafnium oxynitride can be used.

[0309] Next, as shown in Figure 3(C), a resist is applied to the sacrificial layer 110B, and the resist is formed into the desired shape (resist mask: REG) using photolithography. Note that this method involves heat treatment steps such as heating after resist application (PAB: Pre-Applied Bake) and heating after exposure (PEB: Post-Exposure Bake). For example, the PAB temperature is around 100°C, and the PEB temperature is around 120°C. Therefore, the light-emitting device must be able to withstand these processing temperatures.

[0310] Next, using the obtained resist mask REG, a portion of the sacrificial layer 110B not covered by the resist mask REG is removed by etching. After removing the resist mask REG, a portion of the EL layer 103B not covered by the sacrificial layer 110B is removed by etching. The EL layer 103B on electrode 551G and the EL layer 103B on electrode 551R are removed by etching to process the material into a shape with sides (or with exposed sides) or a strip shape extending in a direction intersecting the plane of the paper. Specifically, dry etching is performed using the sacrificial layer 110B with a pattern formed on the EL layer 103B overlapping electrode 551B. If the sacrificial layer 110B has a laminated structure with the first sacrificial layer and the second sacrificial layer, a portion of the second sacrificial layer may be etched with the resist mask REG, then the resist mask REG is removed, and the second sacrificial layer is used as a mask to etch a portion of the first sacrificial layer and process the EL layer 103B into a predetermined shape. These etching processes yield the shape shown in Figure 4(A).

[0311] Next, as shown in Figure 4(B), the EL layer 103G is formed on the sacrificial layer 110B, electrode 551G, and electrode 551R. In Figure 4(B), the hole injection / transport layer 104G, the light-emitting layer, and the electron transport layer 108G, which are included in the EL layer 103G, are formed. For example, the EL layer 103G is formed on the sacrificial layer 110B, electrode 551G, and electrode 551R, covering them, using a vacuum deposition method.

[0312] Next, as shown in Figure 4(C), a sacrificial layer 110G is formed on the EL layer 103G, a resist is applied on the sacrificial layer 110G, the resist is formed into a desired shape (resist mask: REG) using photolithography, a portion of the sacrificial layer 110G not covered by the obtained resist mask is removed by etching, a portion of the EL layer 103G not covered by the sacrificial layer 110G is removed by etching, and the EL layer 103G on electrode 551B and the EL layer 103G on electrode 551R are removed by etching to process into a shape with sides (or exposed sides) or a strip shape extending in a direction intersecting the plane of the paper, as shown in Figure 5(A). Furthermore, if the sacrificial layer 110G has a laminated structure with the first sacrificial layer and the second sacrificial layer described above, a portion of the second sacrificial layer may be etched with a resist mask, then the resist mask may be removed, and the second sacrificial layer may be used as a mask to etch a portion of the first sacrificial layer, thereby processing the EL layer 103G into a predetermined shape.

[0313] Next, as shown in Figure 5(B), the EL layer 103R is formed on the sacrificial layer 110B, the sacrificial layer 110G, and the electrode 551R. In Figure 5(B), the hole injection / transport layer 104R, the light-emitting layer, and the electron transport layer 108R, which are included in the EL layer 103R, are formed. For example, the EL layer 103R is formed on the sacrificial layer 110B, the sacrificial layer 110G, and the electrode 551R, covering them, using a vacuum deposition method.

[0314] Next, as shown in Figure 5(C), a sacrificial layer 110R is formed on the EL layer 103R, a resist is applied on the sacrificial layer 110R, the resist is formed into a desired shape (resist mask: REG) using photolithography, a portion of the sacrificial layer 110R not covered by the obtained resist mask is removed by etching, a portion of the EL layer 103R not covered by the sacrificial layer 110R is removed by etching, and the EL layer 103R on electrode 551B and the EL layer 103R on electrode 551G are removed by etching to process into a shape with sides (or with exposed sides), or a strip shape extending in a direction intersecting the paper plane. If the sacrificial layer 110R has a laminated structure with the first sacrificial layer and the second sacrificial layer, a portion of the second sacrificial layer may be etched with the resist mask, the resist mask may be removed, and a portion of the first sacrificial layer may be etched using the second sacrificial layer as a mask to process the EL layer 103R into a predetermined shape. Furthermore, while leaving the sacrificial layers (110B, 110G, 110R) on the EL layers (103B, 103G, 103R), an insulating layer 107 is formed on the sacrificial layers (110B, 110G, 110R) to obtain the shape shown in Figure 6(A).

[0315] For example, the ALD method can be used to form the insulating layer 107. In this case, the insulating layer 107 is formed in contact with the side surfaces of each EL layer (103B, 103G, 103R), as shown in Figure 6(A). This prevents the penetration of oxygen, moisture, or their constituent elements into the interior from the side surfaces of each EL layer (103B, 103G, 103R). As for the material used for the insulating layer 107, for example, aluminum oxide, magnesium oxide, hafnium oxide, gallium oxide, indium gallium zinc oxide, silicon nitride, or silicon nitride oxide can be used.

[0316] Next, as shown in Figure 6(B), after removing the sacrificial layers (110B, 110G, 110R), an insulating layer (107B, 107G, 107R) is formed by removing a portion of the insulating layer 107, and then an electron injection layer 109 is formed on the EL layer (103B, 103G, 103R). The electron injection layer 109 is formed, for example, by vacuum deposition. The electron injection layer 109 is formed on the electron transport layer (108B, 108G, 108R). The electron injection layer 109 has a structure in which it is in contact with the other layers of each EL layer (103B, 103G, 103R) (hole injection / transport layers (104R, 104G, 104B), light-emitting layer, and electron transport layers (108B, 108G, 108R)) via the insulating layer (107B, 107G, 107R) at its side (or edge).

[0317] Next, as shown in Figure 6(C), electrodes 552 are formed. Electrodes 552 are formed, for example, using a vacuum deposition method. The electrodes 552 are formed on the electron injection layer 109. The electrodes 552 have a structure that contacts the sides (or edges) of each EL layer (103B, 103G, 103R) (however, the EL layers (103B, 103G, 103R) shown in Figure 6(C) include hole injection / transport layers (104R, 104G, 104B), an emissive layer, and electron transport layers (108B, 108G, 108R)) via the electron injection layer 109 and insulating layers (107B, 107G, 107R). This prevents electrical short circuits between each EL layer (103B, 103G, 103R) and the electrode 552, or more specifically, between the hole injection / transport layers (104B, 104G, 104R) of each EL layer (103B, 103G, 103R) and the electrode 552.

[0318] Through the above process, the EL layers 103B, 103G, and 103R of the light-emitting devices 550B, 550G, and 550R can be separated.

[0319] Furthermore, since the separation process of these EL layers (EL layer 103B, EL layer 103G, and EL layer 103R) is performed using photolithography to form patterns, a high-definition light-emitting device (display panel) can be manufactured. In addition, the edges (sides) of the EL layers processed by pattern formation using photolithography have a shape that is substantially the same surface (or is substantially located on the same plane).

[0320] In EL layers, the hole injection layer, particularly the hole transport region located between the anode and the light-emitting layer, often has high conductivity. Therefore, if it is formed as a common layer for adjacent light-emitting devices, it can cause crosstalk. Consequently, by separating the EL layer using a pattern formation method with photolithography, as shown in this example, it is possible to suppress the occurrence of crosstalk between adjacent light-emitting devices.

[0321] <Example 2 of the configuration of the light-emitting device 700> The light-emitting device 700 shown in Figure 7 includes light-emitting devices 550B, 550G, 550R, and an insulating layer 529. The light-emitting devices 550B, 550G, 550R, and the insulating layer 529 are formed on a functional layer 520 provided on a first substrate 510. The functional layer 520 includes drive circuits GD and SD, each composed of multiple transistors, as well as wiring to electrically connect them. These drive circuits, for example, are electrically connected to the light-emitting devices 550B, 550G, and 550R, respectively, and can drive them.

[0322] Furthermore, the light-emitting devices 550B, 550G, and 550R have the device structure shown in Embodiment 2. In particular, Figure 1(A) shows a case where the EL layer 103 in the structure shown differs for each light-emitting device.

[0323] The specific configurations of each light-emitting device shown in Figure 7 are the same as those of light-emitting devices 550B, 550G, and 550R described in Figure 2.

[0324] As shown in Figure 7, the EL layers (103B, 103G, 103R) of each light-emitting device (550B, 550G, 550R) have a hole injection / transport layer (104B, 104G, 104R), an electron transport layer (108B, 108G, 108R), and an electron injection layer 109, respectively.

[0325] Furthermore, since each EL layer, EL layer 103B, EL layer 103G, and EL layer 103R in this configuration undergoes pattern formation using photolithography during the separation process, the edges (sides) of the processed EL layers have substantially the same surface (or are located substantially on the same plane).

[0326] Each light-emitting device has an EL layer 103B, EL layer 103G, and EL layer 103R, each with a gap 580 between them and adjacent light-emitting devices. Here, if the gap 580 is represented by SE as the distance between the EL layers of adjacent light-emitting devices, a smaller distance SE allows for a higher aperture ratio and higher resolution. On the other hand, a larger distance SE allows for greater tolerance of manufacturing process variations between adjacent light-emitting devices, thereby increasing the manufacturing yield. Since the light-emitting devices manufactured according to this specification are suitable for miniaturization processes, the distance SE between the EL layers of adjacent light-emitting devices can be 0.5 μm or more and 5 μm or less, preferably 1 μm or more and 3 μm or less, more preferably 1 μm or more and 2.5 μm or less, and even more preferably 1 μm or more and 2 μm or less. Typically, the distance SE is preferably 1 μm or more and 2 μm or less (for example, 1.5 μm or nearby).

[0327] In EL layers, the hole injection layer, particularly the hole transport region located between the anode and the light-emitting layer, often has high conductivity. Therefore, if it is formed as a common layer for adjacent light-emitting devices, it can cause crosstalk. Consequently, by separating the EL layer using a pattern formation method with photolithography, as shown in this example, it is possible to suppress the occurrence of crosstalk between adjacent light-emitting devices.

[0328] In this specification, devices fabricated using a metal mask or FMM (Fine Metal Mask, a high-resolution metal mask) may be referred to as MM (Metal Mask) structured devices. In addition, in this specification, devices fabricated without using a metal mask or FMM may be referred to as MML (Metal Maskless) structured devices.

[0329] The configuration shown in this embodiment can be used in appropriate combination with the configurations shown in other embodiments.

[0330] (Embodiment 4) In this embodiment, a light-emitting device, which is one aspect of the present invention, will be described using Figures 8(A) to 10(B). The light-emitting device 700 shown in Figures 8(A) to 10(B) has the light-emitting device shown in Embodiment 2. Furthermore, the light-emitting device 700 described in this embodiment can also be called a display panel because it is applicable to the display section of electronic devices and the like.

[0331] As shown in Figure 8(A), the light-emitting device 700 described in this embodiment includes a display area 231, the display area 231 having a pair of pixels 703(i,j). Also, as shown in Figure 8(B), there is a pair of pixels 703(i+1,j) adjacent to the pair of pixels 703(i,j).

[0332] Note that pixel 703(i,j) can contain multiple pixels. For example, multiple pixels displaying colors with different hues can be used. Each of these multiple pixels can be referred to as a subpixel. Alternatively, multiple subpixels can be grouped together and referred to as a single pixel.

[0333] This allows for additive or subtractive color mixing of the colors displayed by the multiple pixels. Alternatively, it enables the display of hues that cannot be displayed by individual pixels.

[0334] Specifically, the pixel 702B(i,j) that displays blue, the pixel 702G(i,j) that displays green, and the pixel 702R(i,j) that displays red can be used as the pixel 703(i,j). In addition, pixels 702B(i,j), 702G(i,j), and 702R(i,j) can each be referred to as subpixels.

[0335] Additionally, a pixel displaying white or the like may be used as pixel 703(i,j) in addition to the above pair. Furthermore, a pixel displaying cyan, a pixel displaying magenta, and a pixel displaying yellow may each be used as a sub-pixel in pixel 703(i,j).

[0336] In addition to the above pair, a pixel that emits infrared light may be used for pixel 703(i,j). Specifically, a pixel that emits light including light with a wavelength of 650 nm to 1000 nm can be used for pixel 703(i,j).

[0337] The display area 231 shown in Figure 8(A) is surrounded by a drive circuit GD and a drive circuit SD. It also has terminals 519 that are electrically connected to the drive circuits GD and SD. Terminals 519 can be electrically connected, for example, to a flexible printed circuit FPC1.

[0338] The drive circuit GD has the function of supplying a first selection signal and a second selection signal. For example, the drive circuit GD is electrically connected to the conductive film G1(i), which will be described later, and supplies the first selection signal, and is electrically connected to the conductive film G2(i), which will be described later, and supplies the second selection signal. The drive circuit SD also has the function of supplying an image signal and a control signal, and the control signal includes a first level and a second level. For example, the drive circuit SD is electrically connected to the conductive film S1g(j), which will be described later, and supplies the image signal, and is electrically connected to the conductive film S2g(j), which will be described later, and supplies the control signal.

[0339] Figure 10(A) shows cross-sectional views of the light-emitting device along the dashed-dotted lines X1-X2 and X3-X4 shown in Figure 8(A). As shown in Figure 10(A), the light-emitting device 700 has a functional layer 520 between the first substrate 510 and the second substrate 770. The functional layer 520 includes the aforementioned drive circuit GD, drive circuit SD, and wiring that electrically connects them. In Figure 10(A), the functional layer 520 is shown to include a pixel circuit 530B(i,j) and a pixel circuit 530G(i,j) and a drive circuit GD, but is not limited to this configuration.

[0340] Furthermore, each pixel circuit of the functional layer 520 (for example, pixel circuits 530B(i,j) and 530G(i,j) shown in Figure 10(A)) is electrically connected to each light-emitting device formed on the functional layer 520 (for example, light-emitting devices 550B(i,j) and 550G(i,j) shown in Figure 10(A)). Specifically, light-emitting device 550B(i,j) is electrically connected to pixel circuit 530B(i,j) via aperture 591B, and light-emitting device 550G(i,j) is electrically connected to pixel circuit 530G(i,j) via aperture 591G. In addition, an insulating layer 705 is provided on the functional layer 520 and each light-emitting device, and the insulating layer 705 has the function of bonding the second substrate 770 and the functional layer 520.

[0341] Furthermore, the second substrate 770 can be a substrate equipped with touch sensors in a matrix. For example, a substrate equipped with a capacitive touch sensor or an optical touch sensor can be used as the second substrate 770. This allows the light-emitting device according to one embodiment of the present invention to be used as a touch panel.

[0342] Furthermore, the specific configuration of the pixel circuit 530G(i,j) is shown in Figure 9(A).

[0343] As shown in Figure 9(A), the pixel circuit 530G(i,j) has switch SW21, switch SW22, transistor M21, capacitor C21, and node N21. The pixel circuit 530G(i,j) also has node N22, capacitor C22, and switch SW23.

[0344] Transistor M21 has a gate electrode electrically connected to node N21, a first electrode electrically connected to light-emitting device 550G(i,j), and a second electrode electrically connected to conductive film ANO.

[0345] Switch SW21 has a first terminal electrically connected to node N21 and a second terminal electrically connected to the conductive film S1g(j). Switch SW21 also has the function of controlling the conduction state or non-conduction state based on the potential of the conductive film G1(i).

[0346] Switch SW22 has a first terminal electrically connected to the conductive film S2g(j) and a function to control the conduction state or non-conduction state based on the potential of the conductive film G2(i).

[0347] Capacitor C21 has a conductive film electrically connected to node N21 and a conductive film electrically connected to the second electrode of switch SW22.

[0348] This allows the image signal to be stored in node N21. Alternatively, the potential of node N21 can be changed using switch SW22. Or, the intensity of the light emitted by the light-emitting device 550G(i,j) can be controlled using the potential of node N21.

[0349] Next, Figure 9(B) shows an example of the specific structure of transistor M21, as explained in Figure 9(A). Note that, as appropriate, a bottom-gate transistor or a top-gate transistor can be used as transistor M21.

[0350] The transistor shown in Figure 9(B) has a semiconductor film 508, a conductive film 504, an insulating film 506, a conductive film 512A, and a conductive film 512B. The transistor is formed, for example, on an insulating film 501C. The transistor also has an insulating film 516 (insulating film 516A and insulating film 516B) and an insulating film 518.

[0351] The semiconductor film 508 has a region 508A that is electrically connected to the conductive film 512A, and a region 508B that is electrically connected to the conductive film 512B. The semiconductor film 508 has a region 508C between regions 508A and 508B.

[0352] The conductive film 504 has a region that overlaps with region 508C, and the conductive film 504 has the function of a gate electrode.

[0353] The insulating film 506 has a region sandwiched between the semiconductor film 508 and the conductive film 504. The insulating film 506 functions as a first gate insulating film.

[0354] The conductive film 512A has either the function of a source electrode or the function of a drain electrode, and the conductive film 512B has either the function of a source electrode or the function of a drain electrode.

[0355] Furthermore, the conductive film 524 can be used in a transistor. The conductive film 524 has a region in which the semiconductor film 508 is sandwiched between it and the conductive film 504. The conductive film 524 functions as a second gate electrode. The insulating film 501D is sandwiched between the semiconductor film 508 and the conductive film 524 and functions as a second gate insulating film.

[0356] The insulating film 516 functions, for example, as a protective film covering the semiconductor film 508. Specifically, the insulating film 516 can include films containing silicon oxide, silicon oxide nitride, silicon nitride, silicon nitride, aluminum oxide, hafnium oxide, yttrium oxide, zirconium oxide, gallium oxide, tantalum oxide, magnesium oxide, lanthanum oxide, cerium oxide, or neodymium oxide.

[0357] The insulating film 518 is preferably made of a material that has the function of suppressing the diffusion of, for example, oxygen, hydrogen, water, alkali metals, alkaline earth metals, etc. Specifically, as the insulating film 518, for example, silicon nitride, silicon oxynitride, aluminum nitride, aluminum oxynitride, etc. are available. Furthermore, it is preferable that the number of nitrogen atoms is greater than the number of oxygen atoms in silicon oxynitride and aluminum oxynitride, respectively.

[0358] Furthermore, in the process of forming the semiconductor film used for the transistors in the pixel circuit, the semiconductor film used for the transistors in the drive circuit can also be formed. For example, a semiconductor film with the same composition as the semiconductor film used for the transistors in the pixel circuit can be used in the drive circuit.

[0359] Furthermore, the semiconductor film 508 can be made of a semiconductor containing elements of Group 14. Specifically, a semiconductor containing silicon can be used for the semiconductor film 508.

[0360] Furthermore, hydrogenated amorphous silicon can be used for the semiconductor film 508. Alternatively, microcrystalline silicon or the like can be used for the semiconductor film 508. This makes it possible to provide a light-emitting device (or display panel) with less display unevenness than, for example, a light-emitting device (or display panel) that uses polysilicon for the semiconductor film 508. Alternatively, it is easier to scale up the light-emitting device.

[0361] Furthermore, polysilicon can be used for the semiconductor film 508. This allows for, for example, a higher field-effect mobility of the transistor compared to a transistor using hydrogenated amorphous silicon for the semiconductor film 508. Alternatively, for example, the driving capability can be increased compared to a transistor using hydrogenated amorphous silicon for the semiconductor film 508. Alternatively, for example, the aperture ratio of the pixels can be improved compared to a transistor using hydrogenated amorphous silicon for the semiconductor film 508.

[0362] Alternatively, for example, the reliability of the transistor can be improved compared to a transistor using hydrogenated amorphous silicon as the semiconductor film 508.

[0363] Alternatively, the temperature required for transistor fabrication can be lowered compared to, for example, transistors using single-crystal silicon.

[0364] Alternatively, the semiconductor film used for the transistors in the drive circuit can be formed using the same process as the semiconductor film used for the transistors in the pixel circuit. Alternatively, the drive circuit can be formed on the same substrate as the substrate on which the pixel circuit is formed. Alternatively, the number of components constituting the electronic device can be reduced.

[0365] Furthermore, single-crystal silicon can be used for the semiconductor film 508. This allows for higher resolution than, for example, a light-emitting device (or display panel) that uses hydrogenated amorphous silicon for the semiconductor film 508. Alternatively, it is possible to provide a light-emitting device with less display unevenness than a light-emitting device that uses polysilicon for the semiconductor film 508. Alternatively, for example, smart glasses or a head-mounted display can be provided.

[0366] Furthermore, a metal oxide can be used for the semiconductor film 508. This allows the pixel circuit to hold the image signal for a longer time compared to a pixel circuit using a transistor with amorphous silicon as the semiconductor film. Specifically, the selection signal can be supplied at a frequency of less than 30 Hz, preferably less than 1 Hz, and more preferably less than once per minute, while suppressing the occurrence of flicker. As a result, fatigue accumulated in the user of the electronic device can be reduced. In addition, power consumption associated with operation can be reduced.

[0367] Furthermore, an oxide semiconductor can be used for the semiconductor film 508. Specifically, an oxide semiconductor containing indium, an oxide semiconductor containing indium, gallium, and zinc, or an oxide semiconductor containing indium, gallium, zinc, and tin can be used for the semiconductor film 508.

[0368] Furthermore, by using an oxide semiconductor as the semiconductor film, it is possible to obtain a transistor with a smaller leakage current in the off state than a transistor using amorphous silicon as the semiconductor film. Therefore, it is preferable to use a transistor using an oxide semiconductor as the semiconductor film for a switch or the like. Moreover, a circuit using a transistor with an oxide semiconductor as the semiconductor film as a switch can maintain the potential of the floating node for a longer time than a circuit using a transistor with an amorphous silicon as the semiconductor film as a switch.

[0369] Figure 10(A) shows a light-emitting device with a structure that extracts light from the second substrate 770 side (top emission type), but as shown in Figure 10(B), a light-emitting device with a structure that extracts light from the first substrate 510 side (bottom emission type) may also be used. In the case of a bottom emission type light-emitting device, the first electrode 401 is formed to function as a semi-transparent / semi-reflective electrode, and the second electrode 404 is formed to function as a reflective electrode.

[0370] Furthermore, although Figures 10(A) and 10(B) describe an active matrix type light-emitting device, the configuration of the light-emitting device shown in Embodiment 2 may also be applied to the passive matrix type light-emitting device shown in Figures 11(A) and 11(B).

[0371] Figure 11(A) is a perspective view showing a passive matrix type light-emitting device, and Figure 11(B) is a cross-sectional view obtained by cutting Figure 11(A) along the X and Y lines. In Figures 11(A) and 11(B), electrodes 952 and 956 are provided on the substrate 951, and an EL layer 955 is provided between electrodes 952 and 956. The ends of electrodes 952 are covered with an insulating layer 953. A partition layer 954 is provided on the insulating layer 953. The side walls of the partition layer 954 have a slope such that the distance between one side wall and the other side wall narrows as it approaches the substrate surface. In other words, the cross-section of the partition layer 954 in the short-side direction is trapezoidal, and the bottom side (the side that faces the same direction as the surface direction of the insulating layer 953 and is in contact with the insulating layer 953) is shorter than the top side (the side that faces the same direction as the surface direction of the insulating layer 953 and is not in contact with the insulating layer 953). In this way, by providing the partition layer 954, it is possible to prevent defects in the light-emitting device caused by static electricity or the like.

[0372] The configuration shown in this embodiment can be used in appropriate combination with the configurations shown in other embodiments.

[0373] (Embodiment 5) In this embodiment, the configuration of an electronic device according to one aspect of the present invention will be explained with reference to Figures 12(A) to 14(B).

[0374] Figures 12(A) to 14(B) illustrate the configuration of an electronic device according to one embodiment of the present invention. Figure 12(A) is a block diagram of the electronic device, and Figures 12(B) to 12(E) are perspective views illustrating the configuration of the electronic device. Figures 13(A) to 13(E) are perspective views illustrating the configuration of the electronic device, and Figures 14(A) and 14(B) are perspective views illustrating the configuration of the electronic device.

[0375] The electronic device 5200B described in this embodiment includes a computing device 5210 and an input / output device 5220 (see Figure 12(A)).

[0376] The arithmetic unit 5210 has a function to receive operation information and a function to supply image information based on the operation information.

[0377] The input / output device 5220 includes a display unit 5230, an input unit 5240, a detection unit 5250, a communication unit 5290, a function for supplying operation information, and a function for supplying image information. Furthermore, the input / output device 5220 also includes a function for supplying detection information, a function for supplying communication information, and a function for receiving communication information.

[0378] The input unit 5240 has the function of supplying operation information. For example, the input unit 5240 supplies operation information based on the operation of the user of the electronic device 5200B.

[0379] Specifically, the input unit 5240 can use a keyboard, hardware buttons, pointing device, touch sensor, illuminance sensor, imaging device, voice input device, eye-tracking device, posture detection device, etc.

[0380] The display unit 5230 has the function of displaying a display panel and image information. For example, the display panel described in Embodiment 2 can be used in the display unit 5230.

[0381] The detection unit 5250 has the function of supplying detection information. For example, it has the function of detecting the surrounding environment in which electronic equipment is being used and supplying it as detection information.

[0382] Specifically, illuminance sensors, imaging devices, posture detection devices, pressure sensors, and human presence sensors can be used in the detection unit 5250.

[0383] The communication unit 5290 has functions for receiving and supplying communication information. For example, it has functions for connecting with other electronic devices or communication networks via wireless or wired communication. Specifically, it has functions such as wireless local area communication, telephone communication, and short-range wireless communication.

[0384] Figure 12(B) shows an electronic device having an external shape that follows a cylindrical column or the like. One example is digital signage. A display panel, which is one aspect of the present invention, can be applied to the display unit 5230. It may also have a function to change the display method according to the illumination of the usage environment. It may also have a function to change the display content when a person is detected. This allows it to be installed, for example, on a building column, or to display advertisements or information, or to be used in digital signage, etc.

[0385] Figure 12(C) shows an electronic device that has the function of generating image information based on the trajectory of a pointer used by the user. Examples include electronic whiteboards, electronic bulletin boards, and electronic signboards. Specifically, a display panel with a diagonal length of 20 inches or more, preferably 40 inches or more, and more preferably 55 inches or more can be used. Alternatively, multiple display panels can be arranged to form a single display area. Alternatively, multiple display panels can be arranged to form a multi-screen.

[0386] Figure 12(D) shows an electronic device that can receive information from other devices and display it on the display unit 5230. One example is a wearable electronic device. Specifically, it can display several options, or the user can select several options and send them back to the information sender. Alternatively, it can have a function to change the display method according to the illumination of the usage environment. This can reduce the power consumption of the wearable electronic device, for example. Alternatively, it can display images on the wearable electronic device so that it can be used suitably even in environments with strong ambient light, such as outdoors on a sunny day.

[0387] Figure 12(E) shows an electronic device having a display unit 5230 with a curved surface that gently curves along the side of the housing. One example is a mobile phone. The display unit 5230 includes a display panel, which has the function of displaying on, for example, the front, side, top, and back. This allows information to be displayed not only on the front of the mobile phone, but also on the sides, top, and back.

[0388] Figure 13(A) shows an electronic device that can receive information from the internet and display it on the display unit 5230. One example is a smartphone. For example, a message that has been created can be viewed on the display unit 5230. Alternatively, a message that has been created can be sent to another device. Alternatively, for example, it has a function to change the display method according to the illumination of the usage environment. This can reduce the power consumption of the smartphone. Alternatively, for example, an image can be displayed on the smartphone so that it can be used suitably even in environments with strong ambient light, such as outdoors on a sunny day.

[0389] Figure 13(B) shows an electronic device that can use a remote controller as an input unit 5240. One example is a television system. Alternatively, it can receive information from a broadcasting station or the internet and display it on the display unit 5230. Alternatively, it can photograph the user using the detection unit 5250. Alternatively, it can transmit the user's video. Alternatively, it can acquire the user's viewing history and provide it to a cloud service. Alternatively, it can acquire recommendation information from a cloud service and display it on the display unit 5230. Alternatively, it can display a program or video based on the recommendation information. Alternatively, it can have a function to change the display method according to the illumination of the usage environment. This allows the video to be displayed on the television system in a way that is suitable for use even when strong sunlight shines into the room on a sunny day.

[0390] Figure 13(C) shows an electronic device that can receive educational materials from the internet and display them on the display unit 5230. One example is a tablet computer. Alternatively, a report can be entered using the input unit 5240 and sent to the internet. Alternatively, the correction results or evaluations of the report can be obtained from a cloud service and displayed on the display unit 5230. Alternatively, appropriate educational materials can be selected and displayed based on the evaluation.

[0391] For example, the display unit 5230 can receive image signals from other electronic devices and display them. Alternatively, it can be propped up on a stand or the like and used as a sub-display. This allows images to be displayed on the tablet computer in a way that is suitable for use even in environments with strong ambient light, such as outdoors on a sunny day.

[0392] Figure 13(D) shows an electronic device having multiple display units 5230. One example is a digital camera. For example, the display unit 5230 can display an image while the detection unit 5250 is capturing it. Alternatively, the captured image can be displayed on the detection unit. Alternatively, the captured image can be decorated using the input unit 5240. Alternatively, a message can be attached to the captured image. Alternatively, it can be transmitted to the internet. Alternatively, it has a function to change the shooting conditions according to the illumination of the usage environment. This makes it possible to display the subject on the digital camera so that it can be viewed favorably even in environments with strong ambient light, such as outdoors on a sunny day.

[0393] Figure 13(E) shows an electronic device that can control other electronic devices by using the electronic device of this embodiment as a master and using other electronic devices as slaves. One example is a portable personal computer. For example, part of the image information can be displayed on the display unit 5230 and the other part of the image information can be displayed on the display unit of the other electronic device. Alternatively, an image signal can be supplied. Alternatively, information to be written can be obtained from the input unit of the other electronic device using the communication unit 5290. This allows, for example, a portable personal computer to utilize a wide display area.

[0394] Figure 14(A) shows an electronic device having a detection unit 5250 that detects acceleration or direction. One example is a goggle-type electronic device. Alternatively, the detection unit 5250 can supply information relating to the user's position or the direction the user is facing. Alternatively, the electronic device can generate image information for the right eye and image information for the left eye based on the user's position or the direction the user is facing. Alternatively, the display unit 5230 has a display area for the right eye and a display area for the left eye. This allows, for example, the display of an immersive virtual reality space on a goggle-type electronic device.

[0395] Figure 14(B) shows an electronic device having an imaging device and a detection unit 5250 that detects acceleration or direction. One example is a glasses-type electronic device. Alternatively, the detection unit 5250 can supply information relating to the user's position or the direction the user is facing. Alternatively, the electronic device can generate image information based on the user's position or the direction the user is facing. This allows, for example, information to be attached to and displayed on a real-world landscape. Alternatively, images of an augmented reality space can be displayed on a glasses-type electronic device.

[0396] This embodiment can be appropriately combined with other embodiments shown in this specification.

[0397] (Embodiment 6) In this embodiment, a configuration in which the light-emitting device described in Embodiment 2 is used as an illumination device will be explained with reference to Figure 15. Figure 15(A) is a cross-sectional view of the line segment ef in the top view of the illumination device shown in Figure 15(B).

[0398] In this embodiment, the lighting device has a first electrode 401 formed on a translucent substrate 400 which serves as a support. The first electrode 401 corresponds to the first electrode 101 in Embodiment 2. When light is extracted from the first electrode 401 side, the first electrode 401 is formed from a translucent material.

[0399] A pad 412 for supplying voltage to the second electrode 404 is formed on the substrate 400.

[0400] An EL layer 403 is formed on the first electrode 401. The EL layer 403 corresponds to the configuration of the EL layer 103 in Embodiment 2. Please refer to the relevant description for details on these configurations.

[0401] A second electrode 404 is formed by covering the EL layer 403. The second electrode 404 corresponds to the second electrode 102 in Embodiment 2. When light emission is extracted from the first electrode 401 side, the second electrode 404 is formed of a material with high reflectivity. Voltage is supplied to the second electrode 404 by connecting it to the pad 412.

[0402] As described above, the lighting device shown in this embodiment has a light-emitting device having a first electrode 401, an EL layer 403, and a second electrode 404. Since this light-emitting device is a light-emitting device with high luminous efficiency, the lighting device in this embodiment can be a lighting device with low power consumption.

[0403] The lighting device is completed by fixing and sealing the substrate 400, on which the light-emitting device having the above configuration is formed, and the sealing substrate 407 using sealing materials 405 and 406. Either sealing material 405 or 406 may be used. In addition, a desiccant can be mixed into the inner sealing material 406 (not shown in Figure 15(B)), which allows for the adsorption of moisture and leads to improved reliability.

[0404] Furthermore, by extending the pad 412 and a portion of the first electrode 401 outside the sealing materials 405 and 406, it can be used as an external input terminal. Alternatively, an IC chip 420 with a converter or the like may be placed on top of it.

[0405] (Embodiment 7) In this embodiment, an example of an application of a lighting device manufactured by applying a light-emitting device, or a light-emitting device which is a part thereof, according to one aspect of the present invention, will be explained with reference to Figure 16.

[0406] As an indoor lighting device, it can be used as a ceiling light 8001. The ceiling light 8001 is available in both surface-mounted and recessed ceiling types. Such lighting devices are constructed by combining a light-emitting device with a housing or cover. It can also be used as a cord pendant type (suspended from the ceiling by a cord).

[0407] Furthermore, the 8002 footlight illuminates the floor surface, enhancing safety underfoot. For example, it is effective for use in bedrooms, stairwells, or corridors. In such cases, the size and shape can be appropriately changed according to the size and structure of the room. It can also be configured as a freestanding lighting device consisting of a light-emitting device and a support base.

[0408] Furthermore, the sheet-type lighting 8003 is a thin, sheet-shaped lighting device. Because it is attached to a wall surface, it does not take up much space and can be used in a wide range of applications. It can also be easily made to cover a large area. It can also be used on curved walls or enclosures.

[0409] Alternatively, a lighting device 8004 can be used in which the light from the light source is controlled to flow only in a desired direction.

[0410] Furthermore, the desk lamp 8005 has a light source 8006, and as the light source 8006, a light-emitting device that is a part of the present invention or a light-emitting device that is a part thereof can be applied.

[0411] In addition to the above, by applying a light-emitting device, or a light-emitting device that is a part thereof, according to one aspect of the present invention, to a part of the furniture installed in the room, it is possible to create a lighting device that also functions as furniture.

[0412] As described above, various lighting devices can be obtained by applying a light-emitting device. These lighting devices are included in one aspect of the present invention.

[0413] Furthermore, the configuration shown in this embodiment can be used in appropriate combination with the configurations shown in other embodiments.

[0414] (Embodiment 8) In this embodiment, a light-emitting device and a light-receiving device applicable to a display device according to one aspect of the present invention will be described with reference to Figure 17.

[0415] Figure 17(A) shows a schematic cross-sectional view of the light-emitting device 805a and the light-receiving device 805b of a display device 810 according to one aspect of the present invention.

[0416] The light-emitting device 805a has a function of emitting light (hereinafter also referred to as the light-emitting function). The light-emitting device 805a has an electrode 801a, an EL layer 803a, and an electrode 802. Preferably, the light-emitting device 805a is a light-emitting device (organic EL device) that utilizes organic EL as shown in Embodiment 2. Therefore, the EL layer 803a sandwiched between the electrode 801a and the electrode 802 has at least a light-emitting layer. The light-emitting layer has a light-emitting material. By applying a voltage between the electrode 801a and the electrode 802, light is emitted from the EL layer 803a. In addition to the light-emitting layer, the EL layer 803a may have various layers such as a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a carrier (hole or electron) blocking layer, and a charge generation layer. Note that an organic compound according to one aspect of the present invention can be used for the EL layer 803a of the light-emitting device 805a.

[0417] The light-receiving device 805b has a function to detect light (hereinafter also referred to as the light-receiving function). The light-receiving device 805b can be, for example, a pn-type or pin-type photodiode. The light-receiving device 805b has an electrode 801b, a light-receiving layer 803b, and an electrode 802. The light-receiving layer 803b, which is sandwiched between electrodes 801b and 802, has at least an active layer. The light-receiving device 805b functions as a photoelectric conversion device and can generate an electric charge in response to light incident on the light-receiving layer 803b, which can be extracted as an electric current. At this time, a voltage may be applied between electrodes 801b and 802. The amount of charge generated is determined based on the amount of light incident on the light-receiving layer 803b.

[0418] The light-receiving device 805b has the function of detecting visible light. The light-receiving device 805b is sensitive to visible light. It is even more preferable that the light-receiving device 805b has the function of detecting both visible light and infrared light. It is preferable that the light-receiving device 805b is sensitive to both visible light and infrared light.

[0419] In this specification, the wavelength range for blue (B) is defined as 400 nm to less than 490 nm, and blue (B) light is defined as having at least one emission spectral peak in this wavelength range. The wavelength range for green (G) is defined as 490 nm to less than 580 nm, and green (G) light is defined as having at least one emission spectral peak in this wavelength range. The wavelength range for red (R) is defined as 580 nm to less than 700 nm, and red (R) light is defined as having at least one emission spectral peak in this wavelength range. In this specification, the wavelength range for visible light is defined as 400 nm to less than 700 nm, and visible light is defined as having at least one emission spectral peak in this wavelength range. The wavelength range for infrared (IR) is defined as 700 nm to less than 900 nm, and infrared (IR) light is defined as having at least one emission spectral peak in this wavelength range.

[0420] The active layer of the light-receiving device 805b contains a semiconductor. Examples of such semiconductors include inorganic semiconductors such as silicon, and organic semiconductors containing organic compounds. It is preferable to use an organic semiconductor device (or organic photodiode) as the light-receiving device 805b, which contains an organic semiconductor in its active layer. Organic photodiodes are easy to thin, lighten, and enlarge, and offer a high degree of freedom in shape and design, making them applicable to various display devices. Furthermore, using an organic semiconductor allows the EL layer 803a of the light-emitting device 805a and the light-receiving layer 803b of the light-receiving device 805b to be formed using the same method (e.g., vacuum deposition), and common manufacturing equipment can be used, which is preferable. Note that an organic compound, according to one aspect of the present invention, can be used for the light-receiving layer 803b of the light-receiving device 805b.

[0421] In one aspect of the present invention, a display device preferably uses an organic EL device as the light-emitting device 805a and an organic photodiode as the light-receiving device 805b. The organic EL device and the organic photodiode can be formed on the same substrate. Therefore, an organic photodiode can be incorporated into a display device using an organic EL device. In addition to the function of displaying images, the display device according to one aspect of the present invention also has one or both of the functions of imaging and sensing.

[0422] Electrodes 801a and 801b are provided on the same plane. Figure 17(A) shows a configuration in which electrodes 801a and 801b are provided on the substrate 800. Electrodes 801a and 801b can be formed, for example, by processing a conductive film formed on the substrate 800 into island shapes. In other words, electrodes 801a and 801b can be formed through the same process.

[0423] The substrate 800 can be a heat-resistant substrate capable of withstanding the formation of the light-emitting device 805a and the light-receiving device 805b. When an insulating substrate is used as the substrate 800, glass substrates, quartz substrates, sapphire substrates, ceramic substrates, organic resin substrates, etc., can be used. In addition, semiconductor substrates such as single-crystal semiconductor substrates made of silicon or silicon carbide, polycrystalline semiconductor substrates, compound semiconductor substrates such as silicon germanium, and SOI substrates can be used.

[0424] In particular, it is preferable to use a substrate 800 on which a semiconductor circuit including semiconductor elements such as transistors is formed on the aforementioned insulating substrate or semiconductor substrate. It is preferable that the semiconductor circuit constitutes, for example, a pixel circuit, a gate line driving circuit (gate driver), a source line driving circuit (source driver), etc. In addition to the above, an arithmetic circuit, a memory circuit, etc. may also be configured.

[0425] Furthermore, electrode 802 is an electrode made of a layer common to both the light-emitting device 805a and the light-receiving device 805b. Of these electrodes, the electrode that emits light or receives light as an incident electrode preferably uses a conductive film that transmits visible light and infrared light. The electrode that does not emit light or receives light as an incident electrode preferably uses a conductive film that reflects visible light and infrared light.

[0426] In one embodiment of the present invention, the electrode 802 in the display device functions as one of the electrodes of the light-emitting device 805a and the light-receiving device 805b.

[0427] Figure 17(B) shows the case where electrode 801a of the light-emitting device 805a has a higher potential than electrode 802. In this case, electrode 801a functions as the anode of the light-emitting device 805a, and electrode 802 functions as the cathode. Also, electrode 801b of the light-receiving device 805b has a lower potential than electrode 802. In Figure 17(B), to make the direction of current flow clearer, the circuit symbol for the light-emitting diode is shown to the left of the light-emitting device 805a, and the circuit symbol for the photodiode is shown to the right of the light-receiving device 805b. Furthermore, the direction of carrier (electron and hole) flow is schematically indicated by arrows within each device.

[0428] In the configuration shown in Figure 17(B), when a first potential is supplied to electrode 801a via the first wiring, a second potential is supplied to electrode 802 via the second wiring, and a third potential is supplied to electrode 801a via the third wiring in the light-emitting device 805a, the relationship between the magnitudes of each potential is first potential > second potential > third potential.

[0429] Figure 17(C) also shows the case where electrode 801a of the light-emitting device 805a has a lower potential than electrode 802. In this case, electrode 801a functions as the cathode of the light-emitting device 805a, and electrode 802 functions as the anode. Also, electrode 801b of the light-receiving device 805b has a lower potential than electrode 802 and a higher potential than electrode 801a. In Figure 17(C), to make the direction of current flow clearer, the circuit symbol for the light-emitting diode is shown to the left of the light-emitting device 805a, and the circuit symbol for the photodiode is shown to the right of the light-receiving device 805b. Furthermore, the direction of carrier (electron and hole) flow is schematically indicated by arrows within each device.

[0430] In the configuration shown in Figure 17(C), when a first potential is supplied to electrode 801a via the first wiring in the light-emitting device 805a, a second potential is supplied to electrode 802 via the second wiring, and a third potential is supplied to electrode 801a via the third wiring, the relationship between the magnitudes of each potential is second potential > third potential > first potential.

[0431] In this embodiment, the resolution of the light-receiving device 805b is 100 ppi or more, preferably 200 ppi or more, more preferably 300 ppi or more, more preferably 400 ppi or more, and even more preferably 500 ppi or more, and can be 2000 ppi or less, 1000 ppi or less, or 600 ppi or less. In particular, by arranging the light-receiving device 805b with a resolution of 200 ppi or more and 600 ppi or less, preferably 300 ppi or more and 600 ppi or less, it can be suitably used for fingerprint imaging. When performing fingerprint authentication using a display device according to one aspect of the present invention, increasing the resolution of the light-receiving device 805b allows for the extraction of fingerprint feature points (Minutia) with high accuracy, for example, thereby improving the accuracy of fingerprint authentication. Furthermore, a resolution of 500 ppi or more is preferable because it allows compliance with standards such as those of the National Institute of Standards and Technology (NIST). Assuming the resolution of the light-receiving device is 500 ppi, each pixel would be 50.8 μm in size, which is sufficient resolution to capture the width of a fingerprint (typically between 300 μm and 500 μm).

[0432] Furthermore, the configuration shown in this embodiment can be used in appropriate combination with the configurations shown in other embodiments. [Examples]

[0433] <<Synthesis Example 1>> In this example, we will describe the synthesis method of the organic compound N-[(3',5'-di-tert-butyl)-1,1'-biphenyl-4-yl]-N-(4-cyclohexylphenyl)-9,9-bis(4-tert-butylphenyl)-9H-fluoren-2-amine (abbreviated as mmtBuBichPAtBu2FLP(2)), which was shown as structural formula (100) in Embodiment 1. The structure of mmtBuBichPAtBu2FLP(2) is shown below.

[0434] [ka]

[0435] <Step 1: Synthesis of bis(4-tert-butylphenyl)-(3-chloro-6-phenylphenyl)methanol> 9.98 g (33.9 mmol) of 4,4'-di-tert-butylbenzophenone was placed in a three-necked flask and purged with nitrogen. 34.0 mL of tetrahydrofuran (THF) was added to this flask and stirred to obtain a 4,4'-di-tert-butylbenzophenone THF solution. 8.26 g (30.9 mmol) of 2-bromo-4'-chloro-1,1'-biphenyl was placed in another three-necked flask and purged with nitrogen. 152 mL of THF was added to this flask, cooled to approximately -80°C and stirred, and 23.5 mL (37.6 mmol) of n-butyllithium (1.6 mol / L hexane solution) was added dropwise using a syringe. After the addition was complete, the mixture was stirred for 1 hour. After stirring, 34.0 mL of the previously prepared 4,4'-di-tert-butylbenzophenone THF solution was added dropwise using a syringe. After the addition was complete, the mixture was returned to room temperature and stirred for 1 hour. After stirring, approximately 25 mL of dilute hydrochloric acid (2.0 mol / L) was added to the solution and stirred for 1 hour. After stirring, the aqueous layer of the mixture was extracted with ethyl acetate, and the extract and the organic layer were washed together with saturated sodium bicarbonate aqueous solution and saturated brine. The organic layer was dried over magnesium sulfate, and after drying, the mixture was filtered by gravity. The resulting solution was concentrated and allowed to dry. Then, toluene was added to obtain a concentrated toluene solution. This toluene solution was added dropwise to ethanol and reprecipitation occurred. The precipitate was filtered at approximately 10°C, and the resulting solid was dried under reduced pressure at approximately 40°C to obtain 12.2 g of the target light brown solid in a yield of 82%. The synthesis scheme is shown in the following formula (a-1).

[0436] [ka]

[0437] <Step 2: Synthesis of 2-chloro-9,9-bis(4-tert-butylphenyl)-9H-fluorene> 12.2 g (25.3 mmol) of bis(4-tert-butylphenyl)-(3-chloro-6-phenylphenyl)methanol, 211 mg (1.23 mmol) of p-toluenesulfonic acid monohydrate, and 126 mL of toluene were added to a three-necked flask. This mixture was heated and stirred at approximately 120°C for approximately 5 hours. After that, the mixture was returned to room temperature, and 21.5 mL of saturated sodium bicarbonate aqueous solution was added and stirred for approximately 1 hour. After stirring, the organic layer and the aqueous layer were separated, and the organic layer was washed with saturated brine. The organic layer was concentrated, and the resulting solution was purified by silica gel column chromatography. The resulting solution was concentrated to obtain a concentrated toluene solution. This toluene solution was added dropwise to ethanol and reprecipitation occurred. The precipitate was filtered at approximately 10°C, and the resulting solid was dried under reduced pressure at approximately 100°C to obtain 11.3 g of the target white solid in 97% yield. The synthesis scheme is shown in formula (a-2) below.

[0438] [ka]

[0439] <Step 3: Synthesis of 3',5'-di-tert-butyl-4-bromo-1,1'-biphenyl> 30.0 g (150 mmol) of 3,5-di-tert-butylbenzeneboronic acid, 50.9 g (180 mmol) of 4-bromoiodobenzene, 62.2 g (450 mmol) of potassium carbonate, 500 mL of toluene, 125 mL of ethanol, and 225 mL of water were placed in a three-necked flask. After degassing under reduced pressure, the flask was purged with nitrogen. 3.5 g (3.0 mmol) of tetrakistriphenylphosphine palladium was added to this mixture, and the mixture was heated under reflux at approximately 80°C for approximately 5 hours. After returning to room temperature, the organic layer and aqueous layer were separated. Magnesium sulfate was added to the organic layer to dry the water, and after filtration, the mixture was concentrated to obtain a brown solid. The obtained solid was purified by silica gel column chromatography. The obtained solution was concentrated and allowed to dry. Then, hexane was added and recrystallized. The mixed solution from which the white solid precipitated was cooled on ice and filtered. The obtained solid was vacuum-dried at approximately 100°C to obtain 44.3 g of the target white solid in a yield of 86%. The synthesis scheme is shown in formula (a-3) below.

[0440] [ka]

[0441] <Step 4: Synthesis of 3',5'-di-tert-butyl-1,1'-biphenyl-4-amine> 36.9 g (107 mmol) of 3',5'-di-tert-butyl-4-bromo-1,1'-biphenyl and 530 mL of toluene were placed in a three-necked flask. After degassing under reduced pressure, the flask was purged with nitrogen. 2.76 g (5.40 mmol) of bis(tri-tert-butylphosphine)palladium was added to this mixture and the mixture was cooled to approximately -15°C and stirred. Then, 120 mL (120 mmol) of bis(trimethylsilyl)amide lithium (abbreviation: LiHMDS) (1.0 mol / L toluene solution) was added dropwise using a syringe. The mixture was then heated and stirred at 120°C for approximately 3 hours. After that, the mixture was returned to room temperature, 100 mL of water was added, and the mixture was stirred for approximately 1 hour. After stirring, the organic layer and the aqueous layer were separated, and the organic layer was washed with saturated sodium bicarbonate aqueous solution and saturated brine. The organic layer was concentrated, and the resulting solution was purified by silica gel column chromatography. The obtained solution was concentrated to yield 29.0 g of the target product, a light brown solid, in 99% yield. The synthesis scheme is shown in formula (a-4) below.

[0442] [ka]

[0443] <Step 5: Synthesis of N-[3',5'-di-tert-butyl-1,1'-biphenyl-3-yl]-9,9-bis(4-tert-butylphenyl)-9H-fluoren-2-amine> 3.64 g (12.9 mmol) of 3',5'-di-tert-butyl-1,1'-biphenyl-4-amine, 5.95 g (12.8 mmol) of 2-chloro-9,9-bis(4-tert-butylphenyl)-9H-fluorene, 3.62 g (37.7 mmol) of sodium-tert-butoxide, and 64.0 mL of xylene were placed in a three-necked flask. After degassing under reduced pressure, the flask was purged with nitrogen. This mixture was heated and stirred to approximately 60°C. Then, 56.2 mg (0.154 mmol) of allyl palladium chloride dimer(II) (abbreviation: (AllylPdCl)2) and 216 mg (0.526 mmol) of 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl (abbreviation: SPhos) were added, and this mixture was heated and stirred at 90°C for approximately 6 hours. Subsequently, the flask temperature was returned to approximately 60°C, and approximately 1 mL of water was added to precipitate the solid. The precipitated solid was filtered off to obtain a solution. The filtrate was concentrated, and the resulting solution was purified by silica gel column chromatography. The obtained solution was concentrated to obtain 7.75 g of the target product, a light brown solid, in 85% yield. The synthesis scheme is shown in the following formula (a-5).

[0444] [ka]

[0445] <Step 6: Synthesis of mmtBuBichPAtBu2FLP(2)> 3.05 g (4.30 mmol) of N-[3',5'-di-tert-butyl-1,1'-biphenyl-3-yl]-9,9-bis(4-tert-butylphenyl)-9H-fluoren-2-amine, 1.04 g (4.35 mmol) of 4-cyclohexyl-1-bromobenzene, 1.26 g (13.1 mmol) of sodium-tert-butoxide, and 24.5 mL of xylene were placed in a three-necked flask. After degassing under reduced pressure, the flask was purged with nitrogen. This mixture was heated and stirred to approximately 60°C. Here, 18.5 mg (0.051 mmol) of allyl palladium chloride dimer(II) (abbreviation: (AllylPdCl)2) and 66.3 mg (0.204 mmol) of di-tert-butyl (1-methyl-2,2-diphenylcyclopropyl)phosphine (abbreviation: cBRIDP®) were added, and this mixture was heated at 100°C for about 5 hours. After that, the temperature of the flask was returned to about 60°C, and about 1 mL of water was added to precipitate the solid. The precipitated solid was filtered off to obtain a solution. The filtrate was concentrated, and the obtained solution was purified by silica gel column chromatography. The obtained solution was concentrated to obtain a concentrated toluene solution. This toluene solution was added dropwise to ethanol and reprecipitation occurred. The precipitate was filtered at about 10°C, and the obtained solid was dried under reduced pressure at about 100°C to obtain 2.18 g of the target white solid in a yield of 88%. The synthesis scheme is shown in the following formula (a-6).

[0446] [ka]

[0447] Nuclear magnetic resonance spectroscopy of the white solid obtained in step 6 above ( 1 The results of the analysis by 1H-NMR are shown below. From these results, it was found that N-[(3',5'-di-tert-butyl)-1,1'-biphenyl-4-yl]-N-(4-cyclohexylphenyl)-9,9-bis(4-tert-butylphenyl)-9H-fluoren-2-amine (abbreviation: mmtBuBichPAtBu2FLP(2)) was synthesized in this synthesis example.

[0448] 1H-NMR(500MHz DMSO-d6):δ=7.82-7.79(m,2H),7.49(d,2H,J=8.0Hz),7.42-7.36(m,5H),7.27-7.23(m,5H),7.15(d,2H, J=8.0Hz),7.01-6.96(m,10H),2.47(br,2H),1.80(br,4H),1.70(brm,1H),1.36(br,22H),1.22(s,18H).

[0449] Next, 2.18 g of the obtained solid was purified by sublimation using the train sublimation method. Sublimation purification was performed by heating at 290°C under conditions of a pressure of 2.60 Pa and an argon flow rate of 10.0 mL / min. After sublimation purification, 1.87 g of a slightly yellowish-white solid was obtained with a recovery rate of 86%.

[0450] Next, the ultraviolet-visible absorption spectrum (hereinafter simply referred to as "absorption spectrum") and emission spectrum of a toluene solution of mmtBuBichPAtBu2FLP(2) were measured. A UV-Vis spectrophotometer (V550, JASCO Corporation) was used to measure the absorption spectrum, and a fluorometer (FS920, Hamamatsu Photonics Ltd.) was used to measure the emission spectrum. Both measurements were performed at room temperature. A quartz cell was used for measurement. The obtained absorption and emission spectrum measurements are shown in Figure 18. The horizontal axis represents wavelength, and the vertical axis represents absorption intensity and emission intensity. The absorption intensity shown in Figure 18 is the result of subtracting the absorption spectrum measured with toluene alone in a quartz cell from the absorption spectrum measured with the toluene solution in a quartz cell.

[0451] As shown in Figure 18, mmtBuBichPAtBu2FLP(2) had an emission peak at 396 nm.

[0452] Next, mmtBuBichPAtBu2FLP(2) was subjected to mass (MS) analysis by liquid chromatography-mass spectrometry (LC / MS analysis).

[0453] LC / MS analysis was performed using a Thermo Fisher Scientific Ultimate 3000 for LC (liquid chromatography) separation, followed by MS (mass spectrometry) analysis using a Thermo Fisher Scientific Q Exactive.

[0454] For LC separation, any column was used with a column temperature of 40°C, and the solvent was appropriately selected for the delivery conditions. The sample was prepared by dissolving mmtBuBichPAtBu2FLP(2) at any concentration in an organic solvent, and the injection volume was 5.0 μL.

[0455] MS / MS measurements were performed on the exact mass of mmtBuBichPAtBu2FLP(2) at m / z = 867.57 using the PRM method. The PRM settings were configured with a target ion mass range of m / z = 867.57 ± 2.0 (isolation window = 4), and detection was performed in positive mode. The NCE (Normalized Collision Energy) for accelerating the target ion in the collision cell was set to 50. The MS spectrum obtained from the MS / MS measurement is shown in Figure 19.

[0456] The results in Figure 19 show that, due to the presence or absence of hydrogen ions and isotopes, the precursor ion of mmtBuBichPAtBu2FLP(2) is mainly detected around m / z=869, and the product ions are detected around m / z=709, 603, and 439.

[0457] Furthermore, the product ion around m / z=709 is presumed to be a state in which one cyclohexylphenyl group has been removed from mmtBuBichPAtBu2FLP(2), suggesting that mmtBuBichPAtBu2FLP(2) contains N-[3',5'-di-tert-butyl-1,1'-biphenyl-3-yl]-9,9-bis(4-tert-butylphenyl)-9H-fluoren-2-amine.

[0458] Furthermore, the product ion around m / z=603 is presumed to be a state in which one 3,5-di-tert-butyl-1,1'-biphenyl group has been removed from mmtBuBichPAtBu2FLP(2), suggesting that mmtBuBichPAtBu2FLP(2) contains N-(4-cyclohexylphenyl)-9,9-bis(4-tert-butylphenyl)-9H-fluoren-2-amine.

[0459] Furthermore, the product ion around m / z=439 is presumed to be a state in which one 9,9-bis(4-tert-butylphenyl)-fluorenyl group has been removed from mmtBuBichPAtBu2FLP(2), suggesting that mmtBuBichPAtBu2FLP(2) contains a 9,9-bis(4-tert-butylphenyl)-fluorenyl group.

[0460] Figure 20 shows the results of measuring the refractive index of mmtBuBichPAtBu2FLP(2) using a spectroscopic ellipsometer (M-2000U, manufactured by J.A. Woolam Japan). For the measurement, a film was used in which each layer material was deposited on a quartz substrate by vacuum deposition, with a thickness of approximately 50 nm. The figure also shows the refractive index of the ordinary ray (n,Ordinary) and the refractive index of the extraordinary ray (n,Extra-ordinary).

[0461] Figure 20 shows that mmtBuBichPAtBu2FLP(2) has a normal refractive index of 1.69 at 465 nm, 1.66 at 520 nm, and 1.63 at 633 nm, indicating that it is a material with a low refractive index.

[0462] Next, the Tg of mmtBuBichPAtBu2FLP(2) was measured. The Tg was measured using a differential scanning calorimetry system (PYRIS1DSC, manufactured by PerkinElmer Japan Co., Ltd.) with the powder placed on an aluminum cell. As a result, the Tg of mmtBuBichPAtBu2FLP(2) was 153°C.

[0463] Next, the HOMO level of mmtBuBichPAtBu2FLP(2) was measured. The HOMO level was determined by cyclic voltammetry (CV). An electrochemical analyzer (manufactured by BAS Corporation, model number: ALS model 600A or 600C) was used for the measurement. As a result, the HOMO level of mmtBuBichPAtBu2FLP(2) was found to be -5.41 eV.

[0464] Furthermore, the GSP of mmtBuBichPAtBu2FLP(2) was determined. Here, we will explain the method for determining the GSP of organic compounds.

[0465] The phenomenon in which the surface potential of a deposited film increases in proportion to its thickness is called giant surface potential, as mentioned above. Generally, the slope when the surface potential of a deposited film measured by a Kelvin probe is plotted in the direction of film thickness is discussed as the magnitude of the giant surface potential, i.e., GSP (mV / nm). However, when two different layers are stacked, the polarization charge density (mC / m) accumulated at their interface... 2 The GSP can be estimated by utilizing the fact that ) changes in relation to the GSP.

[0466] In "Orientational Polarization Phenomena of Polar Molecules and Interface Characteristics of Organic Thin Film Devices" by Hiroshi Noguchi, et al. (Journal of the Vacuum Society of Japan, 2015, Vol. 58, No. 3), it is shown that when organic thin films with different spontaneous polarizations (thin film 1 and thin film 2, where thin film 1 is on the anode side and thin film 2 is on the cathode side) are stacked and an electric current is passed through them, the following equation holds true.

[0467]

number

[0468]

number

[0469] In equation (1), σ if V is the polarization charge density.i V is the hole injection voltage. bi V is the threshold voltage, d2 is the thickness of thin film 2, and ε2 is the dielectric constant of thin film 2. i , V bi This can be estimated from the capacitance-voltage characteristics of the device. Furthermore, the dielectric constant is the refractive index n. o The square of (633nm) can be used. In this way, V estimated from the capacitance-voltage characteristics i , V bi Then, using the dielectric constant ε2 of thin film 2 calculated from the refractive index, and the film thickness d2 of thin film 2, the polarization charge density σ is calculated using equation (1). if It is possible to find this.

[0470] Next, in equation (2), σ if P is the polarization charge density. n This is the GSP of thin film n, ε n σ is the dielectric constant of the thin film n. Here, from equation (1) above, the polarization charge density σ if Since this can be determined, the GSP of thin film 1 can be estimated by using a material with a known GSP as thin film 2.

[0471] In this specification, Alq3, which has a known GSP of (48 (mV / nm)), was used as thin film 2, and the GSP of each thin film was determined.

[0472] Furthermore, if thin film 1 or thin film 2 contains multiple organic compounds, the GSP of the organic compound that is primarily present (for example, the most abundant) can be considered as the "GSP of the organic compounds constituting the layer." Alternatively, if thin film 1 or thin film 2 contains multiple organic compounds, the GSP and content of each organic compound may be calculated, and their weighted average (GSP_ave) may be defined as the "GSP of the organic compounds constituting the layer."

[0473] The results obtained using the above method showed that the GSP of mmtBuBichPAtBu2FLP(2) is 42.9mV / nm. [Examples]

[0474] ≪Synthesis Example 2≫ In this example, we will describe the synthesis method of the organic compound shown as structural formula (101) in Embodiment 1, N-(1,1'-biphenyl-2-yl)-N-[(3',5'-di-tert-butyl)-1,1'-biphenyl-4-yl]-9,9-bis(4-tert-butylphenyl)-9H-fluoren-2-amine (abbreviation: mmtBuBioBitBu2FLP(2)). The structure of mmtBuBioBitBu2FLP(2) is shown below.

[0475] [ka]

[0476] <Step 1: Synthesis of mmtBuBioBitBu2FLP(2)> 3.50 g (150 mmol) of N-[3',5'-di-tert-butyl-1,1'-biphenyl-3-yl]-9,9-bis(4-tert-butylphenyl)-9H-fluoren-2-amine, 1.17 g (180 mmol) of 2-bromo-1,1'-biphenyl, 1.41 g (37.7 mmol) of sodium-tert-butoxide, and 24.5 mL of mesitylene were placed in a three-necked flask. After degassing under reduced pressure, the flask was purged with nitrogen. This mixture was heated and stirred to approximately 60°C. Here, 20.1 mg (0.154 mmol) of allyl palladium chloride dimer(II) (abbreviation: (AllylPdCl)2) and 64.7 mg (0.204 mmol) of di-tert-butyl (1-methyl-2,2-diphenylcyclopropyl)phosphine (abbreviation: cBRIDP®) were added, and the mixture was heated and stirred at 140°C for about 6 hours. After that, the temperature of the flask was returned to about 60°C, and about 1 mL of water was added to precipitate the solid. The precipitated solid was filtered off to obtain a solution. The filtrate was concentrated, and the obtained solution was purified by silica gel column chromatography. The obtained solution was concentrated to obtain 2.91 g of the target product, a light brown solid, in a yield of 69%. The synthesis scheme is shown in formula (b-1) below.

[0477] [ka]

[0478] Nuclear magnetic resonance spectroscopy of the white solid obtained in step 1 above ( 1 The results of the analysis by 1H-NMR are shown below. From these results, it was found that N-(1,1'-biphenyl-2-yl)-N-[(3',5'-di-tert-butyl)-1,1'-biphenyl-4-yl]-9,9-bis(4-tert-butylphenyl)-9H-fluoren-2-amine (abbreviation: mmtBuBioBitBu2FLP(2)) was synthesized in this synthesis example.

[0479] 1 H-NMR (500MHz) DMSO-d6):δ=7.68(d,1H,J=7.5Hz),7.49(d,1H,J=8.0Hz),7.45(dt,1H,J=7.5Hz ,1.0Hz),7.40-7.34(m,7H),7.32-7.25(m,7H),7.19(t,1H,J=7.5Hz),7.10-7.0 3(m,3H),6.95(d,2H,J=7.5Hz),6.90(d,2H,J=8.5Hz),6.82(d,4H,J=8.0Hz),6. 70(d,1H,J=2.0Hz),6.54(dd,1H,J=8.5Hz,1.5Hz),1.33(s,18H),1.26(s,18H).

[0480] Next, 2.89 g of the obtained solid was purified by sublimation using the train sublimation method. Sublimation purification was performed by heating at 272°C under conditions of a pressure of 2.39 Pa and an argon flow rate of 10.0 mL / min. After sublimation purification, 2.37 g of a slightly yellowish-white solid was obtained with a recovery rate of 82%.

[0481] Next, the ultraviolet-visible absorption spectrum (hereinafter simply referred to as "absorption spectrum") and emission spectrum of a toluene solution of mmtBuBioBitBu2FLP(2) were measured. A UV-Vis spectrophotometer (V550, JASCO Corporation) was used to measure the absorption spectrum, and a fluorometer (FS920, Hamamatsu Photonics Ltd.) was used to measure the emission spectrum. Both measurements were performed at room temperature. A quartz cell was used for measurement. The obtained absorption and emission spectrum measurements are shown in Figure 21. The horizontal axis represents wavelength, and the vertical axis represents absorption intensity and emission intensity. The absorption intensity shown in Figure 21 is the result of subtracting the absorption spectrum measured with toluene alone in a quartz cell from the absorption spectrum measured with the toluene solution in a quartz cell.

[0482] As shown in Figure 21, the organic compound mmtBuBioBitBu2FLP(2) had an emission peak at 396 nm.

[0483] Next, the organic compound mmtBuBioBitBu2FLP(2) was subjected to mass (MS) analysis by liquid chromatography-mass spectrometry (LC / MS analysis).

[0484] LC / MS analysis was performed using a Thermo Fisher Scientific Ultimate 3000 for LC (liquid chromatography) separation, followed by MS (mass spectrometry) analysis using a Thermo Fisher Scientific Q Exactive.

[0485] For LC separation, any column was used with a column temperature of 40°C, and the solvent was appropriately selected for the delivery conditions. The sample was prepared by dissolving mmtBuBioBitBu2FLP(2) at any concentration in an organic solvent, and the injection volume was 5.0 μL.

[0486] MS / MS measurements were performed on mmtBuBioBitBu2FLP(2) at its Exact Mass, m / z = 861.53, using the PRM method. The PRM settings were configured with a target ion mass range of m / z = 861.53 ± 2.0 (isolation window = 4), and detection was performed in positive mode. The NCE (Normalized Collision Energy) for accelerating the target ion within the collision cell was set to 50. The MS spectra obtained from the MS / MS measurements are shown in Figure 22.

[0487] The results in Figure 22 show that, due to the presence or absence of hydrogen ions and isotopes, the precursor ion of mmtBuBioBitBu2FLP(2) is mainly detected around m / z=861, and the product ions are detected around m / z=728 and 429.

[0488] Furthermore, the product ion around m / z=728 is presumed to be a state in which one tert-butylphenyl group has been removed from mmtBuBioBitBu2FLP(2), suggesting that mmtBuBioBitBu2FLP(2) contains N-(1,1'-biphenyl-2-yl)-N-[(3',5'-di-tert-butyl)-1,1'-biphenyl-4-yl]-9-(4-tert-butylphenyl)-9H-fluoren-2-amine.

[0489] Furthermore, the product ion around m / z=429 is presumed to be 9,9-bis(4-tert-butylphenyl)-fluorene detached from mmtBuBioBitBu2FLP(2), suggesting that mmtBuBioBitBu2FLP(2) contains a 9,9-bis(4-tert-butylphenyl)-fluorenyl group.

[0490] Figure 23 shows the results of measuring the refractive index of mmtBuBioBitBu2FLP(2) using a spectroscopic ellipsometer (M-2000U, J.A. Woo-Lam Japan). For the measurement, a film was used in which each layer material was deposited on a quartz substrate by vacuum deposition at a thickness of approximately 50 nm. The figure also shows the refractive index of the ordinary ray (n,Ordinary) and the refractive index of the extraordinary ray (n,Extra-ordinary).

[0491] From this figure, it can be seen that mmtBuBioBitBu2FLP(2) has a paraphotometric refractive index of 1.71 at 465 nm, 1.68 at 520 nm, and 1.65 at 633 nm, indicating that it is a material with a low refractive index.

[0492] Next, the Tg of mmtBuBioBitBu2FLP(2) was measured. The Tg was measured using a differential scanning calorimetry system (PYRIS1DSC, manufactured by PerkinElmer Japan Co., Ltd.) with the powder placed on an aluminum cell. As a result, the Tg of mmtBuBioBitBu2FLP(2) was 153°C.

[0493] Next, the HOMO level of mmtBuBioBitBu2FLP(2) was measured. The HOMO level was determined by cyclic voltammetry (CV). An electrochemical analyzer (manufactured by BAS Corporation, model number: ALS model 600A or 600C) was used for the measurement. As a result, the HOMO level of mmtBuBioBitBu2FLP(2) was found to be -5.46 eV.

[0494] Furthermore, the GSP of mmtBuBioBitBu2FLP(2) was determined using the method described in Example 1. As a result, it was found that the GSP of mmtBuBioBitBu2FLP(2) is 37.0 mV / nm. [Examples]

[0495] ≪Synthesis Example 3≫ In this example, we will describe the synthesis method of the organic compound N,N-bis(4-cyclohexylphenyl)-9,9-bis(4-tert-butylphenyl)-9H-fluoren-2-amine (abbreviated as dchPAtBu2FLP(2)), which was shown as structural formula (102) in Embodiment 1. The structure of dchPAtBu2FLP(2) is shown below.

[0496] [ka]

[0497] <Step 1: Synthesis of 4-cyclohexylaniline> 21.5 g (90 mmol) of 4-cyclohexyl-1-bromobenzene and 450 mL of toluene were placed in a three-necked flask. After degassing under reduced pressure, the flask was purged with nitrogen. This solution was cooled and stirred to approximately -20°C. Then, 823 mg (2.25 mmol) of allyl palladium chloride dimer(II) (abbreviated as (AllylPdCl)2) and 3690 mg (9.0 mmol) of di-tert-butyl(1-methyl-2,2-diphenylcyclopropyl)phosphine (abbreviated as cBRIDP®) were added. To this solution, 100 mL (100 mmol) of a toluene solution of 1.0 mol / L lithium bis(hexamethyldisilazide) (abbreviated as Li-N(TMS)2) was added dropwise. The flask was then heated to approximately 120°C, and the mixture was reacted for approximately 2 hours. After cooling, approximately 200 mL of water was added and allowed to stand, separating the organic layer from the aqueous layer. Approximately 100 mL of toluene was added to the resulting aqueous layer to extract the reaction product. The obtained organic layer was mixed with the previously separated organic layer and washed with saturated brine. Magnesium sulfate was added to this solution, the water was dried, and the solution was filtered. The resulting toluene solution was concentrated and purified by silica gel column chromatography. The resulting solution was concentrated to obtain a concentrated toluene solution. This toluene solution was dried under vacuum at approximately 60°C to obtain 14.5 g of the target product, a brownish oily substance, in a yield of 92%. The synthesis scheme is shown in the following formula (c-1).

[0498] [ka]

[0499] <Step 2: Synthesis of N-(4-cyclohexylphenyl)-9,9-bis(4-tert-butylphenyl)-9H-fluoren-2-amine> 876 mg (5.00 mmol) of 4-cyclohexylaniline, 2.32 g (4.99 mmol) of 2-chloro-9,9-bis(4-tert-butylphenyl)-9H-fluorene, 1.45 g (15.1 mmol) of sodium-tert-butoxide, and 25.0 mL of xylene were placed in a three-necked flask. After degassing under reduced pressure, the flask was purged with nitrogen. This mixture was heated and stirred to approximately 60°C. Then, 19.3 mg (0.052 mmol) of allyl palladium chloride dimer(II) (abbreviation: (AllylPdCl)2) and 86.0 mg (0.209 mmol) of 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl (abbreviation: SPhos) were added, and this mixture was heated and stirred at 90°C for approximately 5 hours. After that, the flask temperature was returned to approximately 60°C, and approximately 1 mL of water was added to precipitate the solid. The precipitated solid was filtered off to obtain a solution. The filtrate was concentrated, and the resulting solution was purified by silica gel column chromatography. The obtained solution was concentrated to obtain 2.10 g of the target product, a light brown solid, in 70% yield. The synthesis scheme is shown in formula (c-2) below.

[0500] [ka]

[0501] <Step 3: Synthesis of N,N-bis(4-cyclohexylphenyl)-9,9-bis(4-tert-butylphenyl)-9H-fluoren-2-amine (abbreviation: dchPAtBu2FLP(2))> 2.10 g (3.48 mmol) of N-(4-cyclohexylphenyl)-9,9-bis(4-tert-butylphenyl)-9H-fluoren-2-amine, 841 mg (3.52 mmol) of 4-cyclohexyl-1-bromobenzene, 984 mg (10.2 mmol) of sodium-tert-butoxide, and 18.0 mL of xylene were placed in a three-necked flask. After degassing under reduced pressure, the flask was purged with nitrogen. This mixture was heated and stirred to approximately 50°C. Then, 11.6 mg (0.032 mmol) of allyl palladium chloride dimer(II) (abbreviation: (AllylPdCl)2) and 53.9 mg (0.131 mmol) of 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl (abbreviation: SPhos) were added, and this mixture was heated at 110°C for approximately 3 hours. Subsequently, the flask temperature was returned to approximately 60°C, and approximately 1 mL of water was added to precipitate the solid. The precipitated solid was filtered off to obtain a solution. The filtrate was concentrated, and the resulting solution was purified by silica gel column chromatography. The obtained solution was concentrated to obtain a concentrated toluene solution. This toluene solution was added dropwise to ethanol and reprecipitation occurred. The precipitate was filtered at approximately 10°C, and the resulting solid was dried under reduced pressure at approximately 100°C to obtain 2.24 g of the target white solid in a yield of 84%. The synthesis scheme is shown in the following formula (c-3).

[0502] [ka]

[0503] Nuclear magnetic resonance spectroscopy of the white solid obtained in step 3 above ( 1 The results of the analysis by 1H-NMR are shown below. From these results, it was found that N,N-bis(4-cyclohexylphenyl)-9,9-bis(4-tert-butylphenyl)-9H-fluoren-2-amine (abbreviation: dchPAtBu2FLP(2)) was synthesized in this synthesis example.

[0504] 1H-NMR(500MHz DMSO-d6):δ=7.78-7.74(m,2H),7.39(d,1H,J=7.5Hz),7.35(t,1H,J=7.5Hz),7.23(d,5H,J=8.5Hz),7.08(d,4H,J= 8.0Hz),6.92(d,5H,J=8.5Hz),6.87(d,5H,J=8.0Hz),1.78(brm,8H),1.69(brm,2H),1.34(brm,8H),1.23(s,22H).

[0505] Next, 2.22 g of the obtained solid was purified by sublimation using the train sublimation method. Sublimation purification was performed by heating at 270°C under conditions of a pressure of 2.54 Pa and an argon flow rate of 10.0 mL / min. After sublimation purification, 1.83 g of a slightly yellowish-white solid was obtained with a recovery rate of 82%.

[0506] Next, the ultraviolet-visible absorption spectrum (hereinafter simply referred to as "absorption spectrum") and emission spectrum of a toluene solution of dchPAtBu2FLP(2) were measured. A UV-visible spectrophotometer (V550, JASCO Corporation) was used to measure the absorption spectrum, and a fluorometer (FS920, Hamamatsu Photonics Ltd.) was used to measure the emission spectrum. Both measurements were performed at room temperature. A quartz cell was used for measurement. The obtained absorption and emission spectrum measurements are shown in Figure 24. The horizontal axis represents wavelength, and the vertical axis represents absorption intensity and emission intensity. The absorption intensity shown in Figure 24 is the result of subtracting the absorption spectrum measured with toluene alone in a quartz cell from the absorption spectrum measured with the toluene solution in a quartz cell.

[0507] As shown in Figure 24, the organic compound, dchPAtBu2FLP(2), had an emission peak at 394 nm.

[0508] Figure 25 shows the results of measuring the refractive index of dchPAtBu2FLP(2) using a spectroscopic ellipsometer (M-2000U, J.A. Woo-Lam Japan). For the measurement, a film was used in which each layer material was deposited on a quartz substrate by vacuum deposition, with a thickness of approximately 50 nm. The figure shows the refractive index of the ordinary ray (n,Ordinary) and the refractive index of the extraordinary ray (n,Extra-ordinary).

[0509] From this figure, it can be seen that dchPAtBu2FLP(2) has a paraphotometric refractive index of 1.69 at 465 nm, 1.66 at 520 nm, and 1.64 at 633 nm, indicating that it is a material with a low refractive index.

[0510] Next, the Tg of dchPAtBu2FLP(2) was measured. The Tg was measured using a differential scanning calorimetry system (PYRIS1DSC, manufactured by PerkinElmer Japan Co., Ltd.) with the powder placed on an aluminum cell. As a result, the Tg of dchPAtBu2FLP(2) was 137°C.

[0511] Next, the HOMO level of dchPAtBu2FLP(2) was measured. The HOMO level was determined by cyclic voltammetry (CV). An electrochemical analyzer (manufactured by BAS Corporation, model number: ALS model 600A or 600C) was used for the measurement. As a result, the HOMO level of dchPAtBu2FLP(2) was found to be -5.40 eV.

[0512] Furthermore, the GSP of dchPAtBu2FLP(2) was determined using the method described in Example 1. As a result, it was found that the GSP of dchPAtBu2FLP(2) is 48.7 mV / nm. [Examples]

[0513] In this embodiment, a light-emitting device and a comparative light-emitting device according to one embodiment of the present invention described in the embodiments will be explained. The structural formula of the organic compound used in the light-emitting device according to one embodiment of the present invention is shown below.

[0514] [ka]

[0515] (Method for fabricating light-emitting device 1) As shown in Figure 26, the light-emitting device 1 in this embodiment has a structure in which a hole injection layer 911, a hole transport layer 912, a light-emitting layer 913, an electron transport layer 914, and an electron injection layer 915 are sequentially stacked on a first electrode 901 formed on a glass substrate 900, and a second electrode 903 is stacked on the electron injection layer 915.

[0516] First, a 100 nm thick layer of silver (Ag) was deposited on a glass substrate 900 to form a reflective electrode. Then, a first electrode 901 was formed by depositing indium tin oxide (ITSO) containing silicon dioxide using a sputtering method. The film thickness was 10 nm, and the electrode area was 2 mm × 2 mm.

[0517] Next, as a pretreatment for forming a light-emitting device on the substrate, the substrate surface was washed with water, baked at 200°C for 1 hour, and then subjected to UV ozone treatment for 370 seconds.

[0518] Then, 10 -4 The substrate was introduced into a vacuum deposition apparatus where the internal pressure was reduced to approximately Pa. After vacuum firing at 170°C for 30 minutes in the heating chamber of the vacuum deposition apparatus, the substrate was allowed to cool for about 30 minutes.

[0519] Next, the substrate on which the first electrode 901 is formed is fixed to a substrate holder provided in a vacuum deposition apparatus so that the surface on which the first electrode 901 is formed faces downwards. Then, a hole injection layer 911 is formed on the first electrode 901 by co-depositing 10 nm of N-(1,1'-biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-9,9-dimethyl-9H-fluoren-2-amine (abbreviated as PCBBiF), represented by the above structural formula (i), and an electron acceptor material (OCHD-003) with a molecular weight of 672 and containing fluorine, in a weight ratio of 1:0.04 (=PCBBiF:OCHD-003) using a deposition method with resistance heating.

[0520] Next, PCBBiF was deposited onto the hole injection layer 911 to a thickness of 120 nm, and then an organic compound according to one aspect of the present invention, N-[(3',5'-di-tert-butyl)-1,1'-biphenyl-4-yl]-N-(4-cyclohexylphenyl)-9,9-bis(4-tert-butylphenyl)-9H-fluoren-2-amine (abbreviation: mmtBuBichPAtBu2FLP(2)) (structural formula (100)), was deposited to a thickness of 40 nm to form a hole transport layer 912.

[0521] Next, we have 11-(4-[1,1'-biphenyl]-4-yl-6-phenyl-1,3,5-triazine-2-yl)-11,12-dihydro-12-phenyl-indoro[2,3-a]carbazole (abbreviation: BP-Icz(II)Tzn), represented by the above structural formula (ii), and 9-(2-naphthyl)-9'-phenyl-9H,9'H-3,3'-bicarbazole (abbreviation: βNCCP), represented by the above structural formula (iii), and the above structural formula (iv A light-emitting layer 913 was formed by co-depositing [2-d3-methyl-(2-pyridinyl-κN)benzofl[2,3-b]pyridine-κC]bis[2-(2-pyridinyl-κN)phenyl-κC]iridium(III) (abbreviation: Ir(ppy)2(mbfpypy-d3)) represented by ) at a weight ratio of 0.5:0.5:0.10 (=BP-Icz(II)Tzn:βNCCP:Ir(ppy)2(mbfpypy-d3)) at a density of 40 nm.

[0522] Subsequently, 2-[3'-(9,9-dimethyl-9H-fluoren-2-yl)-1,1'-biphenyl-3-yl]-4,6-diphenyl-1,3,5-triazine (abbreviated as mFBPTzn), represented by the above structural formula (v), was deposited onto the light-emitting layer 913 to a thickness of 10 nm. Then, 2-[3-(2,6-dimethyl-3-pyridinyl)-5-(9-phenantrenyl)phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviated as mPn-mDMePyPTzn), represented by the above structural formula (vi), and 8-quinolinolato-lithium (abbreviated as Liq), represented by the above structural formula (vii), were co-deposited at a weight ratio of 0.5:0.5 (=mPn-mDMePyPTzn:Liq) to form an electron transport layer 914.

[0523] After forming the electron transport layer 914, lithium fluoride (LiF) was deposited at a depth of 1 nm to form the electron injection layer 915. Subsequently, silver (Ag) and magnesium (Mg) were co-deposited at a volume ratio of 10:1 (=Ag:Mg) at a depth of 15 nm to form the second electrode 903, thereby fabricating the light-emitting device 1 of this embodiment. The second electrode 903 is a semi-transmissive / semi-reflective electrode having both light-reflecting and light-transmitting functions, and the light-emitting device of this embodiment is a top-emission type element that extracts light from the second electrode 903. Furthermore, 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzothiophene) (abbreviation: DBT3P-II), represented by structural formula (viii), was deposited at a depth of 70 nm on the second electrode 903 to improve the extraction efficiency.

[0524] Next, we will explain the method for fabricating the comparative light-emitting device. The structural formulas of the organic compounds used in the comparative light-emitting device are shown below.

[0525] [ka]

[0526] (Method for fabricating comparative light-emitting device 1-1) Comparative light-emitting device 1-1 was fabricated in the same manner as light-emitting device 1, except that PCBBiF was deposited on the hole injection layer 911 to a thickness of 110 nm, followed by the deposition of OCHD-003 to a thickness of 1 nm. Furthermore, N-[2-(9,9-diphenyl-9H-fluorenne-4-yl)phenyl]-N-(1,1'-biphenyl-4-yl)-9,9-dimethyl-9H-fluorenne-2-amine (abbreviated as FBiFLPB), represented by the above structural formula (ix), was deposited to a thickness of 40 nm to form a hole transport layer 912.

[0527] (Method for fabricating comparative light-emitting devices 1-2) Comparative light-emitting devices 1-2 were fabricated in the same manner as light-emitting device 1, except that PCBBiF was deposited on the hole injection layer 911 to a thickness of 115 nm, followed by the deposition of OCHD-003 to a thickness of 1 nm. Furthermore, N-(1,1'-biphenyl-2-yl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobi[9H-fluoren]-4-amine (abbreviated as oFBiSF), represented by the above structural formula (x), was deposited to a thickness of 40 nm to form a hole transport layer 912.

[0528] The element structures of the above-mentioned light-emitting device and the comparative light-emitting device are summarized in the table below.

[0529] [Table 1]

[0530] Furthermore, Figure 27 shows the wavelength dependence of the refractive index of the low refractive index material mmtBuBichPAtBu2FLP(2), which was used in part of the hole transport layer, and the reference materials FBiFLPB and oFBiSF, and the table below shows the ordinary refractive index at 520 nm.

[0531] [Table 2]

[0532] The GSP values ​​of the materials used in the hole transport layer are shown in the table below.

[0533] [Table 3]

[0534] The above-mentioned light-emitting device and comparative light-emitting device were sealed with a glass substrate in a glove box under a nitrogen atmosphere to prevent exposure to the atmosphere (sealing material was applied around the element, UV treatment was performed during sealing, and heat treatment was performed at 80°C for 1 hour). After this, the initial characteristics of these light-emitting devices were measured.

[0535] Figure 28 shows the luminance-current density characteristics of light-emitting device 1, comparative light-emitting device 1-1, and comparative light-emitting device 1-2, Figure 29 shows the current efficiency-luminance characteristics, Figure 30 shows the luminance-voltage characteristics, Figure 31 shows the current-voltage characteristics, Figure 32 shows the external quantum efficiency-luminance characteristics, and Figure 33 shows the emission spectra of each light-emitting device at 1000 cd / m². 2 Table 4 shows the main characteristics of the vicinity. A spectroradiometer (Topcon SR-UL1R) was used to measure luminance, CIE chromaticity, and emission spectrum. The external quantum efficiency was calculated using the luminance and emission spectrum measured with the spectroradiometer, assuming that the light distribution characteristics were Lambertsian.

[0536] [Table 4]

[0537] Figures 28 to 33 show that light-emitting device 1, which is a light-emitting device according to one embodiment of the present invention, has improved luminous efficiency compared to comparative light-emitting devices 1-1 and 1-2.

[0538] Furthermore, while comparative light-emitting devices 1-1 and 1-2 use OCHD-003 in the hole transport layer 912, light-emitting device 1 achieves better characteristics compared to comparative light-emitting devices 1-1 and 1-2 even without using OCHD-003 in the hole transport layer 912. This is due to the fact that the GSP of mmtBuBichPAtBu2FLP(2) is higher than that of FBiFLPB and oFBiSF. In other words, by using mmtBuBichPAtBu2FLP(2), which has a high GSP, in the layer of the hole transport layer 912 having a laminated structure that is in contact with the light-emitting layer 913, it becomes easier to inject holes at the laminated interface inside the hole transport layer 912. As a result, light-emitting device 1 can maintain good characteristics even without using OCHD-003 in the hole transport layer 912.

[0539] Therefore, it was found that by using an organic compound according to one aspect of the present invention, the number of layers in the hole transport layer 912 can be reduced by one, thus enabling the fabrication of a highly productive device.

[0540] Furthermore, Figure 34 shows that light-emitting device 1, comparative light-emitting device 1-1, and comparative light-emitting device 1-2 are connected at 2mA (50mA / cm²). 2 The figure shows the change in brightness with respect to the operating time when a constant current is applied and driven. From Figure 34, it can be seen that light-emitting device 1 has a similar lifespan to comparative light-emitting devices 1-1 and 1-2. [Examples]

[0541] In this embodiment, a light-emitting device and a comparative light-emitting device according to one embodiment of the present invention described in the embodiments will be explained. The structural formula of the organic compound used in the light-emitting device according to one embodiment of the present invention is shown below.

[0542] [ka]

[0543] (Method for fabricating light-emitting device 2) As shown in Figure 26, the light-emitting device 2 in this embodiment has a structure in which a hole injection layer 911, a hole transport layer 912, a light-emitting layer 913, an electron transport layer 914, and an electron injection layer 915 are sequentially stacked on a first electrode 901 formed on a glass substrate 900, and a second electrode 903 is stacked on the electron injection layer 915.

[0544] First, a 100 nm thick layer of silver (Ag) was deposited on a glass substrate 900 to form a reflective electrode. Then, a first electrode 901 was formed by depositing indium tin oxide (ITSO) containing silicon dioxide using a sputtering method. The film thickness was 10 nm, and the electrode area was 2 mm × 2 mm.

[0545] Next, as a pretreatment for forming a light-emitting device on the substrate, the substrate surface was washed with water, baked at 200°C for 1 hour, and then subjected to UV ozone treatment for 370 seconds.

[0546] Then, 10 -4 The substrate was introduced into a vacuum deposition apparatus where the internal pressure was reduced to approximately Pa. After vacuum firing at 170°C for 30 minutes in the heating chamber of the vacuum deposition apparatus, the substrate was allowed to cool for about 30 minutes.

[0547] Next, the substrate on which the first electrode 901 is formed is fixed to a substrate holder provided in a vacuum deposition apparatus so that the surface on which the first electrode 901 is formed faces downwards. Then, a hole injection layer 911 is formed on the first electrode 901 by co-depositing 10 nm of N-(1,1'-biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-9,9-dimethyl-9H-fluoren-2-amine (abbreviated as PCBBiF), represented by the above structural formula (i), and an electron acceptor material (OCHD-003) with a molecular weight of 672 and containing fluorine, in a weight ratio of 1:0.04 (=PCBBiF:OCHD-003) using a deposition method with resistance heating.

[0548] Next, PCBBiF was deposited onto the hole injection layer 911 to a thickness of 115 nm, and then an organic compound according to one aspect of the present invention, N-(1,1'-biphenyl-2-yl)-N-[(3',5'-di-tert-butyl)-1,1'-biphenyl-4-yl]-9,9-bis(4-tert-butylphenyl)-9H-fluoren-2-amine (abbreviation: mmtBuBioBitBu2FLP(2)) (structural formula (101)), was deposited to a thickness of 40 nm to form a hole transport layer 912.

[0549] Next, we have 11-(4-[1,1'-biphenyl]-4-yl-6-phenyl-1,3,5-triazine-2-yl)-11,12-dihydro-12-phenyl-indoro[2,3-a]carbazole (abbreviation: BP-Icz(II)Tzn), represented by the above structural formula (ii), and 9-(2-naphthyl)-9'-phenyl-9H,9'H-3,3'-bicarbazole (abbreviation: βNCCP), represented by the above structural formula (iii), and the above structural formula (iv A light-emitting layer 913 was formed by co-depositing [2-d3-methyl-(2-pyridinyl-κN)benzofl[2,3-b]pyridine-κC]bis[2-(2-pyridinyl-κN)phenyl-κC]iridium(III) (abbreviation: Ir(ppy)2(mbfpypy-d3)) represented by ) at a weight ratio of 0.5:0.5:0.10 (=BP-Icz(II)Tzn:βNCCP:Ir(ppy)2(mbfpypy-d3)) at a density of 40 nm.

[0550] Subsequently, 2-[3'-(9,9-dimethyl-9H-fluoren-2-yl)-1,1'-biphenyl-3-yl]-4,6-diphenyl-1,3,5-triazine (abbreviated as mFBPTzn), represented by the above structural formula (v), was deposited onto the light-emitting layer 913 to a thickness of 10 nm. Then, 2-[3-(2,6-dimethyl-3-pyridinyl)-5-(9-phenantrenyl)phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviated as mPn-mDMePyPTzn), represented by the above structural formula (vi), and 8-quinolinolato-lithium (abbreviated as Liq), represented by the above structural formula (vii), were co-deposited at a weight ratio of 0.5:0.5 (=mPn-mDMePyPTzn:Liq) to form an electron transport layer 914.

[0551] After forming the electron transport layer 914, lithium fluoride (LiF) was deposited at a depth of 1 nm to form the electron injection layer 915. Subsequently, silver (Ag) and magnesium (Mg) were co-deposited at a volume ratio of 10:1 (=Ag:Mg) at a depth of 15 nm to form the second electrode 903, thereby fabricating the light-emitting device 2 of this embodiment. The second electrode 903 is a semi-transmissive / semi-reflective electrode having both light-reflecting and light-transmitting functions, and the light-emitting device of this embodiment is a top-emission type element that extracts light from the second electrode 903. Furthermore, 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzothiophene) (abbreviation: DBT3P-II), represented by structural formula (viii), was deposited at a depth of 70 nm on the second electrode 903 to improve the extraction efficiency.

[0552] Next, we will explain the method for fabricating the comparative light-emitting device. The structural formulas of the organic compounds used in the comparative light-emitting device are shown below.

[0553] [ka]

[0554] (Method for fabricating comparative light-emitting device 2-1) Comparative light-emitting device 2-1 was fabricated in the same manner as light-emitting device 2, except that PCBBiF was deposited on the hole injection layer 911 to a thickness of 115 nm, followed by the deposition of OCHD-003 to a thickness of 1 nm. Furthermore, N-[2-(9,9-diphenyl-9H-fluorenne-4-yl)phenyl]-N-(1,1'-biphenyl-4-yl)-9,9-dimethyl-9H-fluorenne-2-amine (abbreviated as FBiFLPB), represented by the above structural formula (ix), was deposited to a thickness of 40 nm to form a hole transport layer 912.

[0555] (Method for fabricating comparative light-emitting device 2-2) Comparative light-emitting device 2-2 was fabricated in the same manner as light-emitting device 2, except that PCBBiF was deposited on the hole injection layer 911 to a thickness of 115 nm, followed by the deposition of OCHD-003 to a thickness of 1 nm. Furthermore, N-(1,1'-biphenyl-2-yl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobi[9H-fluoren]-4-amine (abbreviated as oFBiSF), represented by the above structural formula (x), was deposited to a thickness of 40 nm to form a hole transport layer 912.

[0556] The element structures of the above-mentioned light-emitting device and the comparative light-emitting device are summarized in the table below.

[0557] [Table 5]

[0558] Furthermore, Figure 35 shows the wavelength dependence of the refractive index of mmtBuBioBitBu2FLP(2), a low refractive index material used in part of the hole transport layer, and the reference materials FBiFLPB and oFBiSF, and the table below shows the ordinary refractive index at 520 nm.

[0559] [Table 6]

[0560] The GSP values ​​of the materials used in the hole transport layer are shown in the table below.

[0561] [Table 7]

[0562] The above-mentioned light-emitting device and comparative light-emitting device were sealed with a glass substrate in a glove box under a nitrogen atmosphere to prevent exposure to the atmosphere (sealing material was applied around the element, UV treatment was performed during sealing, and heat treatment was performed at 80°C for 1 hour). After this, the initial characteristics of these light-emitting devices were measured.

[0563] Figure 36 shows the luminance-current density characteristics of light-emitting device 2, comparative light-emitting device 2-1, and comparative light-emitting device 2-2, Figure 37 shows the current efficiency-luminance characteristics, Figure 38 shows the luminance-voltage characteristics, Figure 39 shows the current-voltage characteristics, Figure 40 shows the external quantum efficiency-luminance characteristics, and Figure 41 shows the emission spectra of each light-emitting device at 1000 cd / m². 2 Table 8 shows the main characteristics of the vicinity. A spectroradiometer (Topcon SR-UL1R) was used to measure luminance, CIE chromaticity, and emission spectrum. The external quantum efficiency was calculated using the luminance and emission spectrum measured with the spectroradiometer, assuming that the light distribution characteristics were Lambertsian.

[0564] [Table 8]

[0565] Figures 36 to 41 show that the light-emitting device 2, which is a light-emitting device according to one embodiment of the present invention, has improved luminous efficiency compared to comparative light-emitting devices 2-1 and 2-2.

[0566] Furthermore, while comparative light-emitting devices 2-1 and 2-2 use OCHD-003 in the hole transport layer 912, light-emitting device 2 achieves better characteristics compared to comparative light-emitting devices 2-1 and 2-2 even without using OCHD-003 in the hole transport layer 912. This is due to the fact that the GSP of mmtBuBioBitBu2FLP(2) is higher than that of FBiFLPB and oFBiSF. In other words, by using mmtBuBioBitBu2FLP(2), which has a high GSP, in the layer of the hole transport layer 912 having a stacked structure that is in contact with the light-emitting layer 913, hole injection at the stacked interface inside the hole transport layer 912 becomes easier, making it possible to maintain good characteristics in light-emitting device 2 even without using OCHD-003 in the hole transport layer 912.

[0567] Therefore, it was found that by using an organic compound according to one aspect of the present invention, the number of layers in the hole transport layer 912 can be reduced by one, thus enabling the fabrication of a highly productive device.

[0568] Furthermore, Figure 42 shows that light-emitting device 2, comparative light-emitting device 2-1, and comparative light-emitting device 2-2 are connected at 2mA (50mA / cm²). 2 The figure shows the change in brightness with respect to the operating time when a constant current is applied and driven. From Figure 42, it can be seen that light-emitting device 2 has a similar lifespan to comparative light-emitting devices 2-1 and 2-2. [Explanation of Symbols]

[0569] 101 First electrode 102 Second electrode 103 EL layer 103a EL layer 103b EL layer 103B EL layer 103G EL layer 103R EL layer 104B Hole injection / transport layer 104G Hole Injection / Transport Layer 104R Hole injection / transport layer 107 Insulating layer 107B Insulating layer 107G insulating layer 107R Insulating layer 108B Electron transport layer 108G electron transport layer 108R Electron transport layer 109 Electron injection layer 111 Hole injection layer 111a Hole injection layer 111b Hole injection layer 112 Hole transport layer 112a Hole transport layer 112b Hole transport layer 113 Emitting layer 113a Light-emitting layer 113b Emitting layer 113c emissive layer 114 Electron transport layer 114a Electron transport layer 114b Electron transport layer 115 Electron injection layer 115a Electron injection layer 115b Electron injection layer 231 Display area 400 circuit boards 401 First electrode 403 EL layer 404 Second electrode 405 sealant 406 Sealant 407 Sealing substrate 412 pads 420 IC chips 501C insulating film 501D insulating film 504 Conductive film 506 Insulating film 508 Semiconductor film 508A area 508B area 508C area 510 First substrate 512A Conductive film 512B Conductive film 519 terminals 516 Insulating film 516A insulating film 516B insulating film 518 Insulating Film 520 Functional Layers 524 Conductive film 528 Bulkhead 529 Insulating layer 530B Pixel Circuit 530G Pixel Circuit 550B Light-Emitting Device 550G Light-emitting Device 550R Light-Emitting Device 551B Electrode 551G electrode 551R electrode 552 Electrode 580 Gap 591G opening 591B opening 700 Light-emitting devices 702B pixels 702G pixels 702R pixels 703 pixels 705 Insulating layer 770 circuit boards 800 circuit boards 801a electrode 801b electrode 802 Electrode 803a EL layer 803b Photosensitive layer 805a Light-emitting device 805b Light receiving device 810 Display device 900 glass substrate 901 First electrode 903 Second electrode 911 Hole injection layer 912 Hole transport layer 913 Emitting layer 914 Electron transport layer 915 Electron injection layer 951 circuit board 952 Electrode 953 Insulating layer 954 Partition layer 955 EL layer 956 Electrode 5200B Electronic equipment 5210 Arithmetic unit 5220 Input / Output Device 5230 Display section 5240 Input Section 5250 Detection Unit 5290 Communications Department 8001 Ceiling Light 8002 Footlight 8003 Sheet-type lighting 8004 Lighting device 8005 Desk Lamp 8006 light source

Claims

1. An organic compound represented by general formula (G1): 【Chemistry 1】 (In the formula, Ar １２ represents an aryl group having 6 to 10 carbon atoms forming a ring, and has at least one branched or cyclic alkyl group having 3 to 12 carbon atoms. １２ The total number of carbon atoms in the branched or cyclic alkyl groups having 3 to 12 carbon atoms in Ar is 6 to 36. １１ represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms forming a ring, and n represents an integer of 0 or 1. ２２ represents a substituted or unsubstituted aryl group having 6 to 10 carbon atoms forming a ring. ２１ represents a substituted or unsubstituted arylene group having 6 to 13 carbon atoms forming a ring, and m represents an integer of 0 or 1. １ represents a phenyl group having at least one alkyl group having 1 to 6 carbon atoms. ２ represents a phenyl group having at least one alkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 4 carbon atoms. １ ~R ４ Each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. ５ ~R ８ One of the groups is a bond directly bonded to a nitrogen atom, and the others each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.

2. An organic compound represented by general formula (G2): 【Chemistry 2】 (In the formula, Ar １ represents a phenyl group having at least one alkyl group having 1 to 6 carbon atoms. ２ represents a phenyl group having at least one alkyl group having 1 to 6 carbon atoms, or an alkyl group having 1 to 4 carbon atoms. １ ~R ４ Each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. ５ ~R ８ Any one of R is a bond directly bonded to a nitrogen atom, and the others each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. １０ ~R １４ and R ２０ ~R ２４ Each independently represents a hydrogen atom or a branched or cyclic alkyl group having 3 to 12 carbon atoms. １０ ~R １４ The total number of carbon atoms is 6 to 36. In addition, n and m each independently represent an integer of 0 or 1.

3. An organic compound represented by general formula (G3): 【Chemistry 3】 (In the formula, Ar １ represents a phenyl group having at least one branched or cyclic alkyl group having 3 to 6 carbon atoms. ２ represents a phenyl group having at least one branched or cyclic alkyl group having 3 to 6 carbon atoms, or an alkyl group having 1 to 4 carbon atoms. １ ~R ４ Each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. ５ ~R ８ Any one of R is a bond directly bonded to a nitrogen atom, and the others each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. １０ ~R １４ and R ２０ ~R ２４ Each independently represents a hydrogen atom or a branched or cyclic alkyl group having 3 to 12 carbon atoms. １０ ~R １４ The total number of carbon atoms is 6 to 36. Also, m represents an integer of 0 or 1.

4. An organic compound represented by general formula (G4): 【Chemistry 4】 (In the formula, R １ ~R ４ Each independently represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. ５ ~R ８ Any one of R is a bond directly bonded to a nitrogen atom, and the others each independently represent a hydrogen atom or an alkyl group having 1 to 4 carbon atoms. １０ ~R １４ and R ２０ ~R ２４ Each independently represents a hydrogen atom or a branched or cyclic alkyl group having 3 to 12 carbon atoms. １０ ~R １４ The total number of carbon atoms in R is 6 to 36. ３０ ~R ３４ At least one of R represents a branched or cyclic alkyl group having 3 to 6 carbon atoms, and the others represent a hydrogen atom. ４０ ~R ４４ At least one of the above represents a branched or cyclic alkyl group having 3 to 6 carbon atoms, and the others represent a hydrogen atom. In addition, m represents an integer of 0 or 1.

5. In any one of claims 1 to 4, R １ ~R ４ is a hydrogen atom, R ５ ~R ８ An organic compound in which one of the bonds is directly attached to a nitrogen atom and the others are hydrogen atoms.

6. In any one of claims 2 to 5, R １０ ~R １４ At least one of the above is a tert-butyl group or a cyclohexyl group.

7. In any one of claims 2 to 5, R １０ , R １２ , and R １４ is a hydrogen atom, R １１ and R １３ An organic compound in which is a tert-butyl group or a cyclohexyl group.

8. In any one of claims 2 to 5, R １０ , R １１ , R １３ , and R １４ is a hydrogen atom, R １２ An organic compound in which is a tert-butyl group or a cyclohexyl group.

9. In any one of claims 1 to 8, The layer made of the organic compound has an ordinary refractive index of 1.50 or more and 1.75 or less for light with a wavelength of 465 nm.

10. In any one of claims 1 to 9, The layer made of the organic compound has an ordinary refractive index of 1.50 or more and 1.70 or less for light with a wavelength of 520 nm.

11. In any one of claims 1 to 10, The layer made of the organic compound has an ordinary refractive index of 1.45 or more and 1.70 or less for light with a wavelength of 633 nm.

12. An organic compound represented by any one of structural formulas (100) to (102): 【Chemistry 5】

13. A light-emitting device using the organic compound according to any one of claims 1 to 12.

14. An electronic device comprising: the light-emitting device according to claim 13; and at least one of a detection unit, an input unit, and a communication unit.

15. A light emitting apparatus comprising the light emitting device of claim 13 and at least one of a transistor and a substrate.

16. A lighting device comprising the light-emitting device according to claim 13 and a housing.

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