Compound

Abstract

To provide an organic compound which has high heat resistance, and to provide a novel organic compound which is able to be used for a light emitting device that emits red light or near-infrared light.SOLUTION: The present invention provides an organic compound which is represented by a general formula (G0). In the general formula (G0), Q represents an oxygen atom or a sulfur atom; Ar1 represents a substituted or unsubstituted fused aromatic ring; each of R1 and R2 independently represents a hydrogen atom or a group having from 1 to 100 (inclusive) carbon atoms in total; and at least one of R1 and R2 has a hole-transporting skeleton or a fused ring.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] One embodiment of the present invention relates to an organic compound, a material for a light-emitting device (also referred to as a material for a light-emitting element), a light-emitting device (also referred to as a light-emitting element), a light-emitting device, a light-emitting module, an electronic device, and a lighting device.

[0002] One embodiment of the present invention is not limited to the above technical field. Examples of the technical field of one embodiment of the present invention include a semiconductor device, a display device, a light-emitting device, a power storage device, a memory device, an electronic device, a lighting device, an input device (for example, a touch sensor), an input / output device (for example, a touch panel), a driving method thereof, or a manufacturing method thereof. [Background technology]

[0003] Research and development of light-emitting devices (also called organic EL devices or organic EL elements) that utilize the organic electroluminescence (EL) phenomenon is actively underway. The basic structure of an organic EL device is a layer containing a light-emitting organic compound (hereinafter referred to as the light-emitting layer) sandwiched between a pair of electrodes. By applying a voltage to this organic EL device, light can be emitted from the light-emitting organic compound.

[0004] Examples of luminescent organic compounds include compounds that convert a singlet excited state into luminescence (also referred to as fluorescent compounds or fluorescent materials) and compounds that convert a triplet excited state into luminescence (also referred to as phosphorescent compounds or phosphorescent materials). Patent Document 1 discloses organometallic complexes containing iridium or the like as central metals as phosphorescent compounds.

[0005] When forming an emitting layer of a light-emitting device using a phosphorescent compound, the phosphorescent compound is often dispersed in a matrix of other compounds to suppress quenching due to concentration quenching or triplet-triplet annihilation of the phosphorescent compound. In this case, the compound that forms the matrix is called a host material, and the compound dispersed in the matrix, such as the phosphorescent compound, is called a guest material.

[0006] When a phosphorescent compound is used as a guest material, the host material is required to have a triplet excitation energy (energy difference between the ground state and the triplet excited state) greater than that of the phosphorescent compound.

[0007] Furthermore, since the singlet excitation energy (energy difference between the ground state and the singlet excited state) is larger than the triplet excitation energy, a substance having a large triplet excitation energy also has a large singlet excitation energy. Therefore, a substance having a large triplet excitation energy as described above is also useful in a light-emitting device using a fluorescent compound as a light-emitting substance.

[0008] Organic EL devices have features such as the ease of being made thin and lightweight, the ability to respond quickly to input signals, and the ability to be driven using a low-voltage DC power supply, making them suitable for use in display devices.

[0009] Furthermore, organic EL devices can be formed into a film, allowing for planar light emission. This makes it easy to form a large-area light-emitting device. This is a feature that is difficult to obtain with point light sources such as LEDs (light-emitting diodes) and linear light sources such as fluorescent lamps, making organic EL devices highly useful as planar light sources that can be applied to lighting devices and the like.

[0010] Image sensors are also used in a variety of applications, including personal authentication, defect analysis, medical diagnosis, and security. Image sensors use different wavelengths of light source depending on the application. Image sensors use light of various wavelengths, for example, visible light, short wavelength light such as X-rays, and long wavelength light such as near-infrared light.

[0011] In addition to display devices and lighting devices, applications of light-emitting devices as light sources for the image sensors described above are also being considered. [Prior art documents] [Patent documents]

[0012] [Patent Document 1] Japanese Patent Application Laid-Open No. 2007-137872 Summary of the Invention [Problem to be solved by the invention]

[0013] An object of one embodiment of the present invention is to provide a novel organic compound.An object of one embodiment of the present invention is to provide an organic compound having high heat resistance.An object of one embodiment of the present invention is to provide a novel organic compound that can be used in a light-emitting device.An object of one embodiment of the present invention is to provide a novel organic compound that can be used in a light-emitting device that emits red light or near-infrared light.An object of one embodiment of the present invention is to provide a novel organic compound that can be used as a host material in which a light-emitting substance is dispersed in a light-emitting device.

[0014] Another object of one embodiment of the present invention is to provide a light-emitting device with high emission efficiency.Another object of one embodiment of the present invention is to provide a light-emitting device with low driving voltage.Another object of one embodiment of the present invention is to provide a light-emitting device with a long lifetime.Another object of one embodiment of the present invention is to provide a light-emitting device with high heat resistance.Another object of one embodiment of the present invention is to provide a novel light-emitting device that emits red light or near-infrared light.

[0015] Note that the description of these problems does not preclude the existence of other problems. One embodiment of the present invention does not necessarily have to solve all of these problems. Problems other than these can be extracted from the description in the specification, drawings, and claims. [Means for solving the problem]

[0016] One embodiment of the present invention is an organic compound represented by General Formula (G0).

[0017] [ka]

[0018] In the general formula (G0), Q represents oxygen or sulfur, and Ar 1 represents a substituted or unsubstituted fused aromatic ring, R 1 and R 2 each independently represents hydrogen or a group having a total of 1 to 100 carbon atoms; R 1 and R 2 At least one of them has a skeleton with hole transport properties.

[0019] Another embodiment of the present invention is an organic compound represented by General Formula (G0).

[0020] [ka]

[0021] In the general formula (G0), Q represents oxygen or sulfur, and Ar 1 represents any one of a substituted or unsubstituted naphthalene ring, a substituted or unsubstituted phenanthrene ring, and a substituted or unsubstituted chrysene ring; R 1 and R 2 each independently represents hydrogen or a group having a total of 1 to 100 carbon atoms; R 1 and R 2 At least one of them has a skeleton with hole transport properties.

[0022] The hole transporting skeleton is preferably any one of a substituted or unsubstituted diarylamino group, a substituted or unsubstituted fused aromatic hydrocarbon ring, and a substituted or unsubstituted π-excessive fused heteroaromatic ring.

[0023] Another embodiment of the present invention is an organic compound represented by General Formula (G0).

[0024] [ka]

[0025] In the general formula (G0), Q represents oxygen or sulfur, and Ar 1 represents a substituted or unsubstituted fused aromatic ring, R 1 and R 2 each independently represents hydrogen or a group having a total of 1 to 100 carbon atoms; R 1 and R 2 At least one of the groups has a fused ring.

[0026] Another embodiment of the present invention is an organic compound represented by General Formula (G0).

[0027] [ka]

[0028] In the general formula (G0), Q represents oxygen or sulfur, and Ar 1 represents any one of a substituted or unsubstituted naphthalene ring, a substituted or unsubstituted phenanthrene ring, and a substituted or unsubstituted chrysene ring; R 1 and R 2 each independently represents hydrogen or a group having a total of 1 to 100 carbon atoms; R 1 and R 2 At least one of the groups has a fused ring.

[0029] The fused ring is preferably any one of a substituted or unsubstituted fused aromatic hydrocarbon ring and a substituted or unsubstituted π-excessive fused heteroaromatic ring.

[0030] The fused ring is preferably a substituted or unsubstituted fused heteroaromatic ring having any one of a dibenzothiophene skeleton, a dibenzofuran skeleton, and a carbazole skeleton.

[0031] The fused ring is preferably a substituted or unsubstituted fused aromatic hydrocarbon ring having any one of a naphthalene skeleton, a fluorene skeleton, a triphenylene skeleton, and a phenanthrene skeleton.

[0032] Another embodiment of the present invention is an organic compound represented by General Formula (G0).

[0033] [ka]

[0034] In the general formula (G0), Q represents oxygen or sulfur, and Ar 1 represents a substituted or unsubstituted fused aromatic ring, R 1 and R 2 each independently represents hydrogen or a group having a total of 1 to 100 carbon atoms; R 1 and R 2 At least one of R has a hole transporting skeleton, 1 and R 2 At least one of the above represents a structure represented by general formula (u1): In general formula (u1), α represents a substituted or unsubstituted arylene group having 6 to 25 carbon atoms, n represents an integer of 0 to 4, and A 1 represents any one of a substituted or unsubstituted aryl group having from 6 to 30 carbon atoms and a substituted or unsubstituted heteroaryl group having from 3 to 30 carbon atoms, and * represents a bonding site in general formula (G0).

[0035] Another embodiment of the present invention is an organic compound represented by General Formula (G0).

[0036] [ka]

[0037] In the general formula (G0), Q represents oxygen or sulfur, and Ar 1 represents any one of a substituted or unsubstituted naphthalene ring, a substituted or unsubstituted phenanthrene ring, and a substituted or unsubstituted chrysene ring; R 1 and R 2 each independently represents hydrogen or a group having a total of 1 to 100 carbon atoms; R 1 and R 2At least one of R has a hole transporting skeleton, 1 and R 2 At least one of the above represents a structure represented by general formula (u1): In general formula (u1), α represents a substituted or unsubstituted arylene group having 6 to 25 carbon atoms, n represents an integer of 0 to 4, and A 1 represents any one of a substituted or unsubstituted aryl group having from 6 to 30 carbon atoms and a substituted or unsubstituted heteroaryl group having from 3 to 30 carbon atoms, and * represents a bonding site in general formula (G0).

[0038] In general formula (u1), A 1 is represented by the general formula (A 1 -1) to general formula (A 1 -17) is preferably any one of the following:

[0039] [ka]

[0040] General formula (A 1 -1) to general formula (A 1 -17) Medium, R A1 ~R A11 each independently represents one of hydrogen, a substituted or unsubstituted alkyl group having from 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having from 3 to 7 carbon atoms, and a substituted or unsubstituted aryl group having from 6 to 30 carbon atoms.

[0041] In the general formula (u1), α preferably represents any one of the general formulae (Ar-1) to (Ar-14).

[0042] [ka]

[0043] In general formula (Ar-1) to general formula (Ar-14), R B1 ~R B14each independently represents one of hydrogen, a substituted or unsubstituted alkyl group having from 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having from 3 to 7 carbon atoms, and a substituted or unsubstituted aryl group having from 6 to 30 carbon atoms.

[0044] In each of the organic compounds according to one embodiment of the present invention, in general formula (G0), Ar 1 preferably represents any one of general formulas (t1) to (t3).

[0045] [ka]

[0046] In general formula (t1) to general formula (t3), R 3 ~R 24 each independently represents one of hydrogen, a substituted or unsubstituted alkyl group having from 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having from 3 to 7 carbon atoms, and a substituted or unsubstituted aryl group having from 6 to 30 carbon atoms, and * represents a bonding site in general formula (G0).

[0047] The organic compound of one embodiment of the present invention is preferably represented by general formula (G1).

[0048] [ka]

[0049] In the general formula (G1), Q represents oxygen or sulfur, and Ar 1 represents a substituted or unsubstituted fused aromatic ring (or any one of a substituted or unsubstituted naphthalene ring, a substituted or unsubstituted phenanthrene ring, and a substituted or unsubstituted chrysene ring), R 1 and R 2 each independently represents hydrogen or a group having a total of 1 to 100 carbon atoms; R 1 and R 2 At least one of the groups has a hole-transporting skeleton or fused ring.

[0050] The organic compound of one embodiment of the present invention is preferably represented by any one of General Formulas (G1-1) to (G1-4).

[0051] [ka]

[0052] In the general formulae (G1-1) to (G1-4), Q represents oxygen or sulfur, and R 1 and R 2 each independently represents hydrogen or a group having a total of 1 to 100 carbon atoms; R 1 and R 2 At least one of R has a hole transporting skeleton or fused ring, 3 ~R 8 and R 17 ~R 24 each independently represents one of hydrogen, a substituted or unsubstituted alkyl group having from 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having from 3 to 7 carbon atoms, and a substituted or unsubstituted aryl group having from 6 to 30 carbon atoms.

[0053] Another embodiment of the present invention is a material for a light-emitting device having a furoquinoxaline skeleton to which a fused aromatic ring is fused. Another embodiment of the present invention is a material for a light-emitting device having a structure in which a fused aromatic ring is fused to a furan ring of a furoquinoxaline skeleton. The material for a light-emitting device of one embodiment of the present invention is preferably a material for a light-emitting device that emits red or near-infrared light. The material for a light-emitting device of one embodiment of the present invention is preferably a host material for a light-emitting device. The material for a light-emitting device of one embodiment of the present invention is preferably an electron-transporting material for a light-emitting device.

[0054] One embodiment of the present invention is a light-emitting device including an organic compound or a material for a light-emitting device having any of the above structures.

[0055] One embodiment of the present invention is a light-emitting device including a layer containing an organic compound between a pair of electrodes, the layer containing an organic compound having any of the above structures or a material for a light-emitting device.

[0056] One embodiment of the present invention is a light-emitting device including a layer containing an organic compound between a pair of electrodes, in which the layer containing the organic compound has a light-emitting layer, and the light-emitting layer has any of the above organic compounds or materials for light-emitting devices.

[0057] One embodiment of the present invention is a light-emitting device including a layer containing an organic compound between a pair of electrodes, the layer containing the organic compound including a light-emitting layer and an electron-transport layer, and at least one of the light-emitting layer and the electron-transport layer includes any of the above organic compounds or materials for light-emitting devices.

[0058] One embodiment of the present invention is a light-emitting device including a light-emitting device having any of the above structures and one or both of a transistor and a substrate.

[0059] One embodiment of the present invention is a light-emitting module including the above-described light-emitting device, such as a module to which a connector such as a flexible printed circuit (hereinafter referred to as FPC) or a TCP (Tape Carrier Package) is attached, or a light-emitting module to which an integrated circuit (IC) is mounted by a COG (Chip On Glass) method, a COF (Chip On Film) method, etc. Note that the light-emitting module of one embodiment of the present invention may include only one of a connector and an IC, or may include both.

[0060] One embodiment of the present invention is an electronic device including the above-described light-emitting module and at least one of an antenna, a battery, a housing, a camera, a speaker, a microphone, and an operation button.

[0061] One embodiment of the present invention is a lighting device including the above-described light-emitting device and at least one of a housing, a cover, and a support base. [Effects of the Invention]

[0062] According to one embodiment of the present invention, a novel organic compound can be provided. According to one embodiment of the present invention, an organic compound having high heat resistance can be provided. According to one embodiment of the present invention, a novel organic compound that can be used in a light-emitting device can be provided. According to one embodiment of the present invention, a novel organic compound that can be used in a light-emitting device that emits red light or near-infrared light can be provided. According to one embodiment of the present invention, a novel organic compound that can be used as a host material in which a light-emitting substance is dispersed in a light-emitting device can be provided.

[0063] According to one embodiment of the present invention, a light-emitting device with high emission efficiency can be provided. According to one embodiment of the present invention, a light-emitting device with low driving voltage can be provided. According to one embodiment of the present invention, a light-emitting device with long lifetime can be provided. According to one embodiment of the present invention, a light-emitting device with high heat resistance can be provided. According to one embodiment of the present invention, a novel light-emitting device that emits red light or near-infrared light can be provided.

[0064] Note that the description of these effects does not preclude the existence of other effects. One embodiment of the present invention does not necessarily have all of these effects. Effects other than these can be extracted from the description in the specification, drawings, and claims. [Brief explanation of the drawings]

[0065] [Figure 1] 1A, 1B, 1C, and 1D are cross-sectional views showing examples of light-emitting devices. [Figure 2] Fig. 2A is a top view showing an example of a light emitting device, and Fig. 2B and Fig. 2C are cross-sectional views showing an example of a light emitting device. [Figure 3] 3A and 3C are cross-sectional views showing an example of a light emitting apparatus, and Fig. 3B is a cross-sectional view showing an example of a light emitting device. [Figure 4] 4A and 4B are cross-sectional views showing an example of a light emitting device. [Figure 5]Fig. 5A is a top view showing an example of a light emitting device, Fig. 5B is a cross-sectional view showing an example of a light emitting device, Fig. 5C and Fig. 5D are cross-sectional views showing an example of a transistor. [Figure 6] 6A, 6B, 6C, and 6D are diagrams showing examples of electronic devices. [Figure 7] 7A, 7B, 7C, 7D, 7E, and 7F are diagrams showing examples of electronic devices. [Figure 8] Fig. 8A is a diagram showing an example of the exterior of a car, and Fig. 8B and Fig. 8C are diagrams showing an example of the interior of a car. [Figure 9] Figures 9A and 9C are diagrams showing an example of a biometric authentication device. Figure 9B is a diagram showing an example of a light source. Figure 9D is a diagram showing an example of a non-destructive testing device. Figure 9E is a diagram showing an example of a mobile phone. [Figure 10] FIG. 10 is a 1H-NMR chart of the organic compound represented by structural formula (100). [Figure 11] 11A and 11B are the ultraviolet-visible absorption spectrum and the emission spectrum of the organic compound represented by the structural formula (100). [Figure 12] FIG. 12 is a cross-sectional view showing a light-emitting device according to an embodiment. [Figure 13] FIG. 13 is a graph showing the current density-luminance characteristics of the light-emitting device 1. As shown in FIG. [Figure 14] FIG. 14 is a graph showing the voltage-luminance characteristics of the light-emitting device 1. As shown in FIG. [Figure 15] FIG. 15 is a graph showing the luminance-current efficiency characteristics of the light-emitting device 1. [Figure 16] FIG. 16 is a diagram showing the voltage-current characteristics of the light-emitting device 1. As shown in FIG. [Figure 17] FIG. 17 is a graph showing the luminance-external quantum efficiency characteristics of the light-emitting device 1. As shown in FIG. [Figure 18] FIG. 18 is a diagram showing the emission spectrum of the light-emitting device 1. As shown in FIG. [Figure 19] FIG. 19 shows the results of a reliability test on the light-emitting device 1. As shown in FIG. [Figure 20] FIG. 20 is a graph showing the current density-luminance characteristics of light-emitting devices 2 and 3. [Figure 21] FIG. 21 is a diagram showing the voltage-luminance characteristics of the light-emitting devices 2 and 3. [Figure 22] FIG. 22 is a graph showing the luminance-current efficiency characteristics of light-emitting devices 2 and 3. [Figure 23] FIG. 23 is a diagram showing the voltage-current characteristics of the light-emitting devices 2 and 3. [Figure 24] FIG. 24 is a graph showing the luminance-external quantum efficiency characteristics of light-emitting devices 2 and 3. [Figure 25] FIG. 25 shows the emission spectra of light-emitting devices 2 and 3. [Figure 26] FIG. 26 shows the results of the reliability test of light-emitting devices 2 and 3. [Figure 27] FIG. 27 is a 1H-NMR chart of the organic compound represented by the structural formula (113). DETAILED DESCRIPTION OF THE INVENTION

[0066] The embodiments will be described in detail with reference to the drawings. However, the present invention is not limited to the following description, and it will be readily understood by those skilled in the art that various changes can be made in form and detail without departing from the spirit and scope of the present invention. Therefore, the present invention should not be interpreted as being limited to the description of the embodiments shown below.

[0067] In the configuration of the invention described below, the same parts or parts having similar functions are denoted by the same reference numerals in different drawings, and repeated explanations thereof will be omitted. Furthermore, when referring to similar functions, the same hatch pattern may be used and no particular reference numeral may be assigned.

[0068] Furthermore, for ease of understanding, the position, size, range, etc. of each component shown in the drawings may not represent the actual position, size, range, etc. Therefore, the disclosed invention is not necessarily limited to the position, size, range, etc. disclosed in the drawings.

[0069] The terms "film" and "layer" can be interchangeable depending on the circumstances. For example, the term "conductive layer" can be changed to the term "conductive film." Or, for example, the term "insulating film" can be changed to the term "insulating layer."

[0070] (Embodiment 1) In this embodiment, an organic compound of one embodiment of the present invention will be described.

[0071] [Structure of an organic compound according to one embodiment of the present invention] One embodiment of the present invention is an organic compound having a structure in which a fused aromatic ring is fused to a furoquinoxaline skeleton or a thienoquinoxaline skeleton. Another embodiment of the present invention is a material for a light-emitting device having a structure in which a fused aromatic ring is fused to a furoquinoxaline skeleton or a thienoquinoxaline skeleton. The material for a light-emitting device is preferably a material for a light-emitting device that emits red or near-infrared light. The material for a light-emitting device is preferably a host material or an electron-transporting material for a light-emitting device.

[0072] A quinoxaline skeleton has a structure in which a benzene ring is fused to a pyrazine ring. Therefore, by using a furoquinoxaline skeleton or a thienoquinoxaline skeleton, a π-conjugated system can be extended, the lowest unoccupied molecular orbital (LUMO) level can be deepened, and energy stability can be achieved, compared with a case in which a furopyrazine skeleton or a thienopyrazine skeleton is used. Furthermore, by deepening the LUMO level, the triplet excitation level (T1 level) can be lowered. Furthermore, by condensing a fused aromatic ring to a furoquinoxaline skeleton or a thienoquinoxaline skeleton, a π-conjugated system can be extended, the LUMO level can be deepened, and energy stability can be achieved, and the T1 level can be lowered, compared with a case in which a condensed aromatic ring is not included or a case in which a monocyclic aromatic ring is condensed. For these reasons, the organic compound of one embodiment of the present invention can be suitably used in a light-emitting device that emits light with a long wavelength (e.g., red to near-infrared).

[0073] Light-emitting substances with long emission wavelengths tend to have low T1 levels and deep LUMO levels. Therefore, the organic compound of one embodiment of the present invention is preferably used in combination with a light-emitting substance with a long emission wavelength. By using a light-emitting substance with a long emission wavelength as a guest material and the organic compound of one embodiment of the present invention as a host material, the emission efficiency of a light-emitting device can be increased and the driving voltage can be reduced.

[0074] Furthermore, organic compounds having a pyrazine ring are characterized by a higher glass transition temperature and higher heat resistance than organic compounds having a pyrimidine ring.The organic compound of one embodiment of the present invention has a structure in which a fused aromatic ring is fused to a furoquinoxaline skeleton or a thienoquinoxaline skeleton (i.e., a skeleton having a pyrazine ring), and therefore has higher heat resistance than a structure in which the fused aromatic ring is fused to a furopyrimidine skeleton or a thienopyrimidine skeleton, and is an organic compound suitable for a light-emitting device with a long emission wavelength.

[0075] Light-emitting devices used in high-temperature environments, such as those installed in automobiles, require high heat resistance. Furthermore, light-emitting devices also require high heat resistance when exposed to high temperatures during product manufacturing processes, such as a sealing process using glass frit. For these reasons, materials used in light-emitting devices are sometimes required to have a glass transition temperature (Tg) of 100°C or higher, or even 120°C or higher. In one embodiment of the present invention, the Tg of an organic compound can be set to 100°C or higher, or even 120°C or higher, thereby providing a material suitable for light-emitting devices that require high heat resistance.

[0076] The organic compound of one embodiment of the present invention can be used, for example, as a host material in which a light-emitting substance is dispersed in a light-emitting device.

[0077] Furthermore, the organic compound of one embodiment of the present invention has a high electron-transport property, and therefore can be used as an electron-transport material in a light-emitting device.

[0078] Specifically, one embodiment of the present invention is an organic compound represented by general formula (GO). Note that not only organic compounds having structures represented by the following general formulas, but also light-emitting device materials having such structures are also embodiments of the present invention.

[0079] [ka]

[0080] In the general formula (G0), Q represents oxygen or sulfur, and Ar 1 represents a substituted or unsubstituted fused aromatic ring, R 1 and R 2 each independently represents hydrogen or a group having a total of 1 to 100 carbon atoms; R 1 and R 2 At least one of them has a skeleton with hole transport properties.

[0081] Another embodiment of the present invention is an organic compound represented by General Formula (G0).

[0082] [ka]

[0083] In the general formula (G0), Q represents oxygen or sulfur, and Ar 1 represents any one of a substituted or unsubstituted naphthalene ring, a substituted or unsubstituted phenanthrene ring, and a substituted or unsubstituted chrysene ring; R 1 and R 2 each independently represents hydrogen or a group having a total of 1 to 100 carbon atoms; R 1 and R 2 At least one of them has a skeleton with hole transport properties.

[0084] R 1 and R 2The hole-transporting skeleton possessed by at least one of the above is preferably any one of a substituted or unsubstituted diarylamino group, a substituted or unsubstituted fused aromatic hydrocarbon ring, and a substituted or unsubstituted π-excessive fused heteroaromatic ring.

[0085] The fused aromatic hydrocarbon ring preferably has any one of a naphthalene skeleton, a fluorene skeleton, a triphenylene skeleton, and a phenanthrene skeleton.

[0086] The π-excessive fused heteroaromatic ring is preferably a fused heteroaromatic ring having any one of a dibenzothiophene skeleton, a dibenzofuran skeleton, and a carbazole skeleton. The dibenzothiophene skeleton can improve the reliability of the light-emitting device compared to the dibenzofuran skeleton or the carbazole skeleton. The carbazole skeleton can improve the luminous efficiency of the light-emitting device compared to the dibenzothiophene skeleton or the dibenzofuran skeleton.

[0087] In this specification and the like, the fused heteroaromatic ring refers not only to a carbazole ring, a dibenzothiophene ring, and a dibenzofuran ring, but also to a fused ring having a carbazole skeleton, a dibenzothiophene skeleton, or a dibenzofuran skeleton in the ring structure, such as a benzocarbazole ring, a dibenzocarbazole ring, an indolocarbazole ring, a benzoindolocarbazole ring, a dibenzoindolocarbazole ring, a benzindolobenzocarbazole ring, a benzonaphthothiophene ring, or a benzonaphthofuran ring (i.e., a fused ring in which a ring is further fused to a carbazole skeleton, a dibenzothiophene skeleton, or a dibenzofuran skeleton).

[0088] Another embodiment of the present invention is an organic compound represented by General Formula (G0).

[0089] [ka]

[0090] In the general formula (G0), Q represents oxygen or sulfur, and Ar1 represents a substituted or unsubstituted fused aromatic ring, R 1 and R 2 each independently represents hydrogen or a group having a total of 1 to 100 carbon atoms; R 1 and R 2 At least one of the groups has a fused ring.

[0091] Another embodiment of the present invention is an organic compound represented by General Formula (G0).

[0092] [ka]

[0093] In the general formula (G0), Q represents oxygen or sulfur, and Ar 1 represents any one of a substituted or unsubstituted naphthalene ring, a substituted or unsubstituted phenanthrene ring, and a substituted or unsubstituted chrysene ring; R 1 and R 2 each independently represents hydrogen or a group having a total of 1 to 100 carbon atoms; R 1 and R 2 At least one of the groups has a fused ring.

[0094] R 1 and R 2 The fused ring possessed by at least one of the above is preferably any one of a substituted or unsubstituted fused aromatic hydrocarbon ring and a substituted or unsubstituted π-excessive fused heteroaromatic ring.

[0095] The fused ring is preferably a substituted or unsubstituted fused heteroaromatic ring having any one of a dibenzothiophene skeleton, a dibenzofuran skeleton, and a carbazole skeleton.

[0096] As described above, in this specification and the like, the fused heteroaromatic ring includes not only a carbazole ring, a dibenzothiophene ring, and a dibenzofuran ring, but also a fused ring in which a ring is further fused to a carbazole skeleton, a dibenzothiophene skeleton, or a dibenzofuran skeleton.

[0097] The fused ring is preferably a substituted or unsubstituted fused aromatic hydrocarbon ring having any one of a naphthalene skeleton, a fluorene skeleton, a triphenylene skeleton, and a phenanthrene skeleton.

[0098] Another embodiment of the present invention is an organic compound represented by General Formula (G0).

[0099] [ka]

[0100] In the general formula (G0), Q represents oxygen or sulfur, and Ar 1 represents a substituted or unsubstituted fused aromatic ring, R 1 and R 2 each independently represents hydrogen or a group having a total of 1 to 100 carbon atoms; R 1 and R 2 At least one of R has a hole transporting skeleton, 1 and R 2 At least one of the above represents a structure represented by general formula (u1): In general formula (u1), α represents a substituted or unsubstituted arylene group having 6 to 25 carbon atoms, n represents an integer of 0 to 4, and A 1 represents any one of a substituted or unsubstituted aryl group having from 6 to 30 carbon atoms and a substituted or unsubstituted heteroaryl group having from 3 to 30 carbon atoms, and * represents a bonding site in general formula (G0).

[0101] Another embodiment of the present invention is an organic compound represented by General Formula (G0).

[0102] [ka]

[0103] In the general formula (G0), Q represents oxygen or sulfur, and Ar 1represents any one of a substituted or unsubstituted naphthalene ring, a substituted or unsubstituted phenanthrene ring, and a substituted or unsubstituted chrysene ring; R 1 and R 2 each independently represents hydrogen or a group having a total of 1 to 100 carbon atoms; R 1 and R 2 At least one of R has a hole transporting skeleton, 1 and R 2 At least one of the above represents a structure represented by general formula (u1): In general formula (u1), α represents a substituted or unsubstituted arylene group having 6 to 25 carbon atoms, n represents an integer of 0 to 4, and A 1 represents any one of a substituted or unsubstituted aryl group having from 6 to 30 carbon atoms and a substituted or unsubstituted heteroaryl group having from 3 to 30 carbon atoms, and * represents a bonding site in general formula (G0).

[0104] In general formula (u1), A 1 is represented by the general formula (A 1 -1) to general formula (A 1 -17) is preferably any one of the following:

[0105] [ka]

[0106] General formula (A 1 -1) to general formula (A 1 -17) Medium, R A1 ~R A11 each independently represents one of hydrogen, a substituted or unsubstituted alkyl group having from 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having from 3 to 7 carbon atoms, and a substituted or unsubstituted aryl group having from 6 to 30 carbon atoms.

[0107] In the general formula (u1), examples of the arylene group having 6 to 25 carbon atoms include a phenylene group, a naphthalenediyl group, a biphenyldiyl group, an anthracenediyl group, a phenanthrenediyl group, a triphenylenediyl group, a 9H-fluorenediyl group, a 9,9-dimethylfluorenediyl group, and a 9,9'-spirobifluorenediyl group.

[0108] In the general formula (u1), α preferably represents any one of the general formulae (Ar-1) to (Ar-14).

[0109] [ka]

[0110] In general formula (Ar-1) to general formula (Ar-14), R B1 ~R B14 each independently represents one of hydrogen, a substituted or unsubstituted alkyl group having from 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having from 3 to 7 carbon atoms, and a substituted or unsubstituted aryl group having from 6 to 30 carbon atoms.

[0111] In each of the organic compounds according to one embodiment of the present invention, in general formula (G0), Ar 1 preferably represents any one of general formulas (t1) to (t3).

[0112] [ka]

[0113] In general formula (t1) to general formula (t3), R 3 ~R 24 each independently represents one of hydrogen, a substituted or unsubstituted alkyl group having from 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having from 3 to 7 carbon atoms, and a substituted or unsubstituted aryl group having from 6 to 30 carbon atoms, and * represents a bonding site in general formula (G0).

[0114] Among the organic compounds represented by the general formula (G0), the organic compound represented by the general formula (G1) is more preferable, as this makes it possible to further lower the T1 level of the organic compound.

[0115] [ka]

[0116] In the general formula (G1), Q represents oxygen or sulfur, and Ar 1 represents a substituted or unsubstituted fused aromatic ring (or any one of a substituted or unsubstituted naphthalene ring, a substituted or unsubstituted phenanthrene ring, and a substituted or unsubstituted chrysene ring), R 1 and R 2 each independently represents hydrogen or a group having a total of 1 to 100 carbon atoms; R 1 and R 2 At least one of the groups has a hole-transporting skeleton or fused ring.

[0117] Among the organic compounds represented by the general formula (G0), an organic compound represented by any one of the general formulae (G1-1) to (G1-4) is particularly preferable.

[0118] [ka]

[0119] In the general formulae (G1-1) to (G1-4), Q represents oxygen or sulfur, and R 1 and R 2 each independently represents hydrogen or a group having a total of 1 to 100 carbon atoms; R 1 and R 2 At least one of R has a hole transporting skeleton or fused ring, 3 ~R 8 and R 17 ~R 24each independently represents one of hydrogen, a substituted or unsubstituted alkyl group having from 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having from 3 to 7 carbon atoms, and a substituted or unsubstituted aryl group having from 6 to 30 carbon atoms.

[0120] In the general formula (G0), the general formula (G1), and the general formulas (G1-1) to (G1-4), R 1 and R 2 Examples of the group having a total carbon number of 1 to 100 that R has include a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 7 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, and a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms. 1 and R 2 At least one of the groups has the above-mentioned hole-transporting skeleton or fused ring.

[0121] In addition, general formula (G0), general formula (G1), general formula (t1) to general formula (t3), general formula (G1-1) to general formula (G1-4), general formula (u1), general formula (A 1 -1) to general formula (A 1 -17), and in "substituted or unsubstituted X" (X is various rings, skeletons, groups, etc.) in the general formulae (Ar-1) to (Ar-14), when X has a substituent, examples of the substituent include alkyl groups having 1 to 7 carbon atoms such as a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, an isobutyl group, a sec-butyl group, a tert-butyl group, a pentyl group, and a hexyl group; cycloalkyl groups having 5 to 7 carbon atoms such as a cyclopentyl group, a cyclohexyl group, a cycloheptyl group, and a 8,9,10-trinorbornanyl group; and aryl groups having 6 to 12 carbon atoms such as a phenyl group, a naphthyl group, and a biphenyl group.

[0122] General formula (t1) to general formula (t3), general formula (G1-1) to general formula (G1-4), general formula (A 1 -1) to general formula (A 1-17) and in the general formulae (Ar-1) to (Ar-14), examples of the alkyl group having 1 to 6 carbon atoms include a methyl group, an ethyl group, a propyl group, an isopropyl group, a butyl group, a sec-butyl group, an isobutyl group, a tert-butyl group, a pentyl group, an isopentyl group, a sec-pentyl group, a tert-pentyl group, a neopentyl group, a hexyl group, an isohexyl group, a 3-methylpentyl group, a 2-methylpentyl group, a 2-ethylbutyl group, a 1,2-dimethylbutyl group, a 2,3-dimethylbutyl group, and an n-heptyl group.

[0123] General formula (t1) to general formula (t3), general formula (G1-1) to general formula (G1-4), general formula (A 1 -1) to general formula (A 1 -17) and general formulae (Ar-1) to (Ar-14), examples of the cycloalkyl group having 3 to 7 carbon atoms include a cyclopropyl group, a cyclobutyl group, a cyclopentyl group, a cyclohexyl group, a 1-methylcyclohexyl group, a 2,6-dimethylcyclohexyl group, a cycloheptyl group, and a cyclooctyl group.

[0124] General formula (t1) to general formula (t3), general formula (G1-1) to general formula (G1-4), general formula (u1), general formula (A 1 -1) to general formula (A 1 -17) and in the general formulae (Ar-1) to (Ar-14), examples of the aryl group having 6 to 30 carbon atoms include a phenyl group, an o-tolyl group, an m-tolyl group, a p-tolyl group, a mesityl group, an o-biphenyl group, an m-biphenyl group, a p-biphenyl group, a 1-naphthyl group, a 2-naphthyl group, a fluorenyl group, a 9,9-dimethylfluorenyl group, a spirofluorenyl group, a phenanthrenyl group, an anthracenyl group, and a fluoranthenyl group.

[0125] In the general formula (G0), the general formula (G1), and the general formulas (G1-1) to (G1-4), R 1 and R 2The above descriptions can be cited as specific examples of the alkyl group having from 1 to 6 carbon atoms, the cycloalkyl group having from 3 to 7 carbon atoms, and the aryl group having from 6 to 30 carbon atoms in the group having a total of from 1 to 100 carbon atoms contained in formula (u1). Furthermore, examples of the group having a total of from 1 to 100 carbon atoms and the heteroaryl group having from 3 to 30 carbon atoms in general formula (u1) include monovalent groups such as a carbazolyl group, a benzocarbazolyl group, a dibenzocarbazolyl group, an indolocarbazolyl group, a benzoindolocarbazolyl group, a dibenzoindolocarbazolyl group, a benzindolobenzcarbazolyl group, a dibenzothienyl group, a benzonaphthothienyl group, a dibenzofuranyl group, and a benzonaphthofuranyl group.

[0126] Specific examples of the organic compound according to one embodiment of the present invention include the organic compounds represented by structural formulas (100) to (117), although the present invention is not limited thereto.

[0127] [ka]

[0128] [ka]

[0129] [Method for synthesizing an organic compound according to one embodiment of the present invention] Various reactions can be applied as a method for synthesizing an organic compound of one embodiment of the present invention. A method for synthesizing an organic compound represented by General Formula (G0) is exemplified below. An example of a method for synthesizing an organic compound represented by General Formula (G0') is described below. The organic compound represented by General Formula (G0') is a furoquinoxaline derivative having a fused aromatic ring or a thienoquinoxaline derivative having a fused aromatic ring, and is one embodiment of the organic compound represented by General Formula (G0).

[0130] [ka]

[0131] In the general formula (GO'), Q represents oxygen or sulfur, and Ar 1 represents a substituted or unsubstituted fused aromatic ring, R 1 represents a group having 1 to 100 carbon atoms, and R 1 has a hole-transporting skeleton or fused ring.

[0132] <Method for synthesizing organic compound represented by general formula (G0')> First, as shown in the synthesis scheme (A-1), an arylboronic acid (a1) substituted with a methyloxy group or a methylthio group is coupled with a quinoxaline derivative (a2) substituted with an amino group and a halogen atom to obtain an intermediate (a3). Then, the intermediate (a3) is reacted with tert-butyl nitrite to cause cyclization, thereby obtaining a furoquinoxaline derivative having a fused aromatic ring or a thienoquinoxaline derivative having a fused aromatic ring (a4). In the synthesis scheme (A-1), Y 1 If Y is a halogen, then the aromatic boronic acid (Y 3 -(α)nB 2 The intermediate (a5) obtained by coupling with the quinoxaline derivative (a4) can also be used in the subsequent reaction.

[0133] [ka]

[0134] In the synthetic scheme (A-1), Q represents oxygen or sulfur, and Ar 1 represents a substituted or unsubstituted fused aromatic ring, Y 1 represents a halogen or an aromatic ring containing a halogen, and Y 1 is one or two, and Y 2 represents a halogen, and Y 3 represents an aromatic ring containing a halogen, and Y 3 represents one or two, α represents a substituted or unsubstituted arylene group having 6 to 25 carbon atoms, n represents an integer of 0 to 4, B 1 and B 2respectively represent boronic acid, boronic acid ester, cyclic triol borate salt, etc. The cyclic triol borate salt may be a potassium salt or a sodium salt in addition to a lithium salt.

[0135] In the synthesis scheme (A-1), the organic compounds represented by the general formulas (a4) and (a5) are raw materials for the organic compound of one embodiment of the present invention as shown in the synthesis scheme (A-2).

[0136] Next, as shown in the synthesis scheme (A-2), the furoquinoxaline derivative having a fused aromatic ring or the thienoquinoxaline derivative having a fused aromatic ring (a4) obtained in the synthesis scheme (A-1) is coupled with a boronic acid compound (b1) to obtain an organic compound represented by the general formula (G0').

[0137] [ka]

[0138] In the synthetic scheme (A-2), Q represents oxygen or sulfur, and Ar 1 represents a substituted or unsubstituted fused aromatic ring, R 1 represents a group having 1 to 10 carbon atoms, and R 1 has a hole transporting skeleton, and Y 1 represents one or two halogens, B 3 represents a boronic acid, a boronate ester, a cyclic triol borate salt, or the like. Note that the cyclic triol borate salt may be a potassium salt or a sodium salt in addition to a lithium salt.

[0139] Various types of arylboronic acids (a1) substituted with a methyloxy group or a methylthio group, quinoxaline derivatives (a2) substituted with an amino group and a halogen, and boronic acid compounds (b1) used in the synthesis schemes (A-1) and (A-2) are commercially available or can be synthesized, so that numerous types of furoquinoxaline derivatives or thienoquinoxaline derivatives fused with a fused aromatic ring, as represented by the general formula (G0'), can be synthesized. Thus, the organic compound of one embodiment of the present invention is characterized by a wide variety of compounds.

[0140] Although the synthesis method of the organic compound of one embodiment of the present invention has been described above, the present invention is not limited thereto, and the organic compound may be synthesized by another synthesis method.

[0141] As described above, the organic compound of one embodiment of the present invention has high heat resistance and is suitable as a material (particularly a host material or an electron-transporting material) for a light-emitting device that emits red light to near-infrared light. By using the organic compound of one embodiment of the present invention, the emission efficiency of a light-emitting device that emits red light to near-infrared light can be increased. Furthermore, by using the organic compound of one embodiment of the present invention, the lifetime of a light-emitting device that emits red light to near-infrared light can be extended. Furthermore, by using the organic compound of one embodiment of the present invention, the heat resistance of a light-emitting device that emits red light to near-infrared light can be increased. Furthermore, by using the organic compound of one embodiment of the present invention, the reliability of a light-emitting device that emits red light to near-infrared light can be improved.

[0142] This embodiment mode can be combined with other embodiment modes as appropriate. In addition, in this specification, when a plurality of configuration examples are shown in one embodiment mode, the configuration examples can be combined as appropriate.

[0143] (Embodiment 2) In this embodiment, a light-emitting device of one embodiment of the present invention will be described with reference to Fig. 1. In this embodiment, a light-emitting device that has a function of emitting visible light or near-infrared light will be described.

[0144] [Example of light-emitting device configuration] <Basic structure of light-emitting devices> 1A to 1D show an example of a light-emitting device having an EL layer between a pair of electrodes.

[0145] 1A has a structure (single structure) in which an EL layer 103 is sandwiched between a first electrode 101 and a second electrode 102. The EL layer 103 has at least a light-emitting layer.

[0146] FIG. 1B shows an example of a layered structure of the EL layer 103. In this embodiment, a case where the first electrode 101 functions as an anode and the second electrode 102 functions as a cathode will be described as an example. 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 stacked on the first electrode 101. Each of the hole injection layer 111, the hole transport layer 112, the light-emitting layer 113, the electron transport layer 114, and the electron injection layer 115 may have a single-layer structure or a layered structure. When the first electrode 101 is a cathode and the second electrode 102 is an anode, the layering order is reversed.

[0147] The light-emitting device may have multiple EL layers between a pair of electrodes. For example, the light-emitting device preferably has n EL layers (n is an integer of 2 or more) and has a charge generation layer 104 between the (n-1)th EL layer and the nth EL layer.

[0148] Fig. 1C shows a light-emitting device with a tandem structure having two EL layers (EL layers 103a and 103b) between a pair of electrodes, and Fig. 1D shows a light-emitting device with a tandem structure having three EL layers (EL layers 103a, 103b, and 103c).

[0149] Each of the EL layers 103a, 103b, and 103c has at least a light-emitting layer. Even when multiple EL layers are included, such as in the tandem structure shown in Figures 1C and 1D, each EL layer can have a stacked structure similar to that of the EL layer 103 shown in Figure 1B. Each of the EL layers 103a, 103b, and 103c can have one or more layers selected from the group consisting of a hole injection layer 111, a hole transport layer 112, an electron transport layer 114, and an electron injection layer 115.

[0150] 1C has the function of injecting electrons into one of the EL layers 103a and 103b and injecting holes into the other when a voltage is applied between the first electrode 101 and the second electrode 102. Therefore, in FIG. 1C, when a voltage is applied to the first electrode 101 so that the potential of the first electrode 101 is higher than that of the second electrode 102, electrons are injected from the charge generation layer 104 into the EL layer 103a and holes are injected into the EL layer 103b.

[0151] From the viewpoint of light extraction efficiency, the charge generation layer 104 preferably transmits visible light or near-infrared light (specifically, the transmittance of the charge generation layer 104 for visible light or near-infrared light is 40% or more). Furthermore, the charge generation layer 104 functions even if it has lower conductivity than the first electrode 101 and the second electrode 102.

[0152] Note that, when the EL layers are provided in contact with each other and the same structure as the charge generation layer 104 is formed between them, the EL layers can be provided in contact with each other without a charge generation layer therebetween. For example, when a charge generation region is formed on one surface of the EL layer, the EL layer can be provided in contact with that surface.

[0153] Tandem-structure light-emitting devices have higher current efficiency than single-structure devices, and require less current to emit light at the same brightness. This extends the life of the light-emitting devices and improves the reliability of light-emitting devices and electronic devices.

[0154] The light-emitting layer 113 may contain a light-emitting material or a combination of materials to produce fluorescent or phosphorescent light of a desired wavelength. The light-emitting layer 113 may also have a stacked structure with layers that emit light of different wavelengths. In this case, different light-emitting materials and other materials may be used for each of the stacked light-emitting layers. The EL layers 103a, 103b, and 103c shown in FIGS. 1C and 1D may emit light of different wavelengths. In this case, different light-emitting materials and other materials may also be used for each of the light-emitting layers. For example, in FIG. 1C, the EL layer 103a may emit red and green light, and the EL layer 103b may emit blue light. This results in a light-emitting device that emits white light as a whole. A single light-emitting device may also have multiple light-emitting layers or EL layers that emit the same color. For example, in FIG. 1D, by configuring EL layer 103a to emit a first blue light, EL layer 103b to emit yellow or yellow-green light and red light, and EL layer 103c to emit a second blue light, it is possible to obtain a light-emitting device that emits white light as a whole.

[0155] In the light-emitting device according to one embodiment of the present invention, the light emitted from the EL layer may be resonated between a pair of electrodes to enhance the light emission. For example, in FIG. 1B, the first electrode 101 is a reflective electrode and the second electrode 102 is a semi-transparent and semi-reflective electrode, thereby forming a micro-optical resonator (microcavity) structure, which enhances the light emission from the EL layer 103.

[0156] By applying a microcavity structure to a light-emitting device, it is possible to extract light of different wavelengths (monochromatic light) even if the device has the same EL layer. This eliminates the need to form different functional layers for each pixel (so-called separate coating) to obtain different emitted colors. This makes it easy to achieve high resolution. It can also be combined with a colored layer (color filter). Furthermore, it is possible to increase the emission intensity of a specific wavelength in the front direction, thereby reducing power consumption.

[0157] When the first electrode 101 of the light-emitting device is a reflective electrode having a laminated structure of a conductive film reflective to visible light or near-infrared light and a conductive film transmissive to visible light or near-infrared light, optical adjustment can be performed by controlling the film thickness of the transmissive conductive film. Specifically, it is preferable to adjust the inter-electrode distance between the first electrode 101 and the second electrode 102 to be approximately mλ / 2 (where m is a natural number) for the wavelength λ of light obtained from the light-emitting layer 113.

[0158] 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 (light-emitting region) in the light-emitting layer 113 where the desired light is obtained and the optical distance from the second electrode 102 to the region (light-emitting region) in the light-emitting layer 113 where the desired light is obtained to be approximately (2m'+1)λ / 4 (where m' is a natural number). Note that the light-emitting region here refers to the recombination region of holes and electrons in the light-emitting layer 113.

[0159] By performing such optical adjustment, the spectrum of the light obtained from the light-emitting layer 113 can be narrowed, and light emission with good color purity can be obtained.

[0160] In the above case, the optical distance between the first electrode 101 and the second electrode 102 can be strictly 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-mentioned effect can be sufficiently achieved by assuming any position of the first electrode 101 or the second electrode 102 as the reflective region. Furthermore, the optical distance between the first electrode 101 and the light-emitting layer from which desired light is obtained can be strictly 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 desired light is obtained. However, since it is difficult to precisely determine the reflective region of the first electrode 101 or the light-emitting region of the light-emitting layer from which desired light is obtained, the above-mentioned effect can be sufficiently achieved by assuming any position of the first electrode 101 as the reflective region and any position of the light-emitting layer from which desired light is obtained as the light-emitting region.

[0161] At least one of the first electrode 101 and the second electrode 102 is an electrode that is transparent to visible light or near-infrared light. The transmittance of the electrode that is transparent to visible light or near-infrared light is 40% or more. When the electrode that is transparent to visible light or near-infrared light is the semi-transparent / semi-reflective electrode, the reflectance of the electrode to visible light or near-infrared light is 20% or more and 80% or less, preferably 40% or more and 70% or less. The resistivity of these electrodes is 1×10 -2 Ωcm or less is preferable.

[0162] When the first electrode 101 or the second electrode 102 is an electrode (reflective electrode) that is reflective to visible light or near-infrared light, the reflectance of the reflective electrode to visible light or near-infrared light is set to 40% or more and 100% or less, preferably 70% or more and 100% or less. The resistivity of this electrode is 1×10 -2 Ωcm or less is preferable.

[0163] <Specific structure of the light-emitting device> Next, a specific structure of the light-emitting device will be described, using a light-emitting device having a single structure as shown in Figure 1B.

[0164] <First electrode and second electrode> The materials forming the first electrode 101 and the second electrode 102 can be any combination of the following materials, as long as they fulfill the functions of both electrodes described above. For example, metals, alloys, electrically conductive compounds, and mixtures thereof can be used. Specific examples include In-Sn oxide (also referred to as ITO), In-Si-Sn oxide (also referred to as ITSO), In-Zn oxide, and In-W-Zn oxide. Other metals that can be used include 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), and neodymium (Nd), as well as alloys containing any combination of these metals. Other examples that can be used include elements belonging to Group 1 or 2 of the periodic table (e.g., lithium (Li), cesium (Cs), calcium (Ca), and strontium (Sr)) that are not listed above, rare earth metals such as europium (Eu) and ytterbium (Yb), and alloys containing appropriate combinations of these, graphene, and the like.

[0165] When a light-emitting device having a microcavity structure is fabricated, the first electrode 101 is formed as a reflective electrode, and the second electrode 102 is formed as a semi-transmissive and semi-reflective electrode. Therefore, a single or multiple desired conductive materials can be used to form a single layer or a laminated layer. The second electrode 102 is formed by selecting a material in the same manner as above after the EL layer 103 is formed. These electrodes can be fabricated by sputtering or vacuum deposition.

[0166] <Hole injection layer and hole transport layer> The hole injection layer 111 is a layer that injects holes from the first electrode 101, which is an anode, to the EL layer 103, and is a layer that contains a material with high hole injection properties.

[0167] Examples of materials with high hole injection properties include transition metal oxides such as molybdenum oxide, vanadium oxide, ruthenium oxide, tungsten oxide, and manganese oxide, and phthalocyanine compounds such as phthalocyanine (abbreviated as HPc) and copper phthalocyanine (abbreviated as CuPc).

[0168] Materials with high hole injection properties include 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), 4,4'-bis(N-{4-[N'-(3-methylphenyl)-N'-phenylamino]phenyl}-N-phenylamino)biphenyl (abbreviation: DNTPD), 1,3,5-tris[N- Aromatic amine compounds such as (4-diphenylaminophenyl)-N-phenylamino]benzene (abbreviation: DPA3B), 3-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3,6-bis[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA2), and 3-[N-(1-naphthyl)-N-(9-phenylcarbazol-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1) can be used.

[0169] Examples of materials with high hole injection properties include poly(N-vinylcarbazole) (abbreviation: PVK), poly(4-vinyltriphenylamine) (abbreviation: PVTPA), poly[N-(4-{N'-[4-(4-diphenylamino)phenyl]phenyl-N'-phenylamino}phenyl) methacrylamide] (abbreviation: PTPDMA), and poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)benzidine] (abbreviation: Poly-TPD). Alternatively, polymer compounds with added acids, such as poly(3,4-ethylenedioxythiophene) / poly(styrenesulfonic acid) (abbreviation: PEDOT / PSS) and polyaniline / poly(styrenesulfonic acid) (PAni / PSS), can also be used.

[0170] A composite material containing a hole-transporting material and an acceptor material (electron-accepting material) can also be used as a material with high hole-injection properties. In this case, electrons are extracted from the hole-transporting material by the acceptor material, generating holes in the hole-injection layer 111, which are then injected into the light-emitting layer 113 via the hole-transporting layer 112. The hole-injection layer 111 may be formed as a single layer made of a composite material containing a hole-transporting material and an acceptor material, or may be formed by laminating the hole-transporting material and the acceptor material as separate layers.

[0171] The hole transport layer 112 is a layer that transports holes injected from the first electrode 101 by the hole injection layer 111 to the light-emitting layer 113. The hole transport layer 112 is a layer containing a hole transport material. It is particularly preferable to use a hole transport material used for the hole transport layer 112 that has a highest occupied molecular orbital (HOMO) level that is the same as or close to the HOMO level of the hole injection layer 111.

[0172] The acceptor material used for the hole-injection layer 111 can be an oxide of a metal belonging to Groups 4 to 8 of the periodic table. Specific examples include molybdenum oxide, vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, tungsten oxide, manganese oxide, and rhenium oxide. Among these, molybdenum oxide is particularly preferable because it is stable in the air, has low hygroscopicity, and is easy to handle. Other organic acceptors that can be used include quinodimethane derivatives, chloranil derivatives, and hexaazatriphenylene derivatives. Examples of compounds having an electron-withdrawing group (a halogen group or a cyano group) include 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviation: F4-TCNQ), chloranil, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene (abbreviation: HAT-CN), 1,3,4,5,7,8-hexafluorotetracyano-naphthoquinodimethane (abbreviation: F6-TCNNQ), etc. In particular, compounds such as HAT-CN in which an electron-withdrawing group is bonded to a fused aromatic ring having multiple heteroatoms are preferred because they are thermally stable. Radialene derivatives having electron-withdrawing groups (especially halogen groups such as fluoro groups or cyano groups) are also preferred because of their extremely high electron-accepting properties. Specific examples include α,α',α''-1,2,3-cyclopropanetriylidene tris[4-cyano-2,3,5,6-tetrafluorobenzeneacetonitrile], α,α',α''-1,2,3-cyclopropanetriylidene tris[2,6-dichloro-3,5-difluoro-4-(trifluoromethyl)benzeneacetonitrile], and α,α',α''-1,2,3-cyclopropanetriylidene tris[2,3,4,5,6-pentafluorobenzeneacetonitrile].

[0173] The hole transporting material used in the hole injection layer 111 and the hole transport layer 112 is 10 -6 cm 2 A substance having a hole mobility of / Vs or more is preferred. Note that other substances can also be used as long as they have a higher hole transporting property than electron transporting property.

[0174] As the hole transporting material, a material with high hole transporting properties such as a π-electron rich heteroaromatic compound (for example, a carbazole derivative, a thiophene derivative, a furan derivative, etc.) or an aromatic amine (a compound having an aromatic amine skeleton) is preferred.

[0175] Examples of carbazole derivatives (compounds having a carbazole skeleton) include bicarbazole derivatives (for example, 3,3'-bicarbazole derivatives) and aromatic amines having a carbazolyl group.

[0176] Specific examples of bicarbazole derivatives (for example, 3,3′-bicarbazole derivatives) include 3,3′-bis(9-phenyl-9H-carbazole) (abbreviation: PCCP), 9,9′-bis(1,1′-biphenyl-4-yl)-3,3′-bi-9H-carbazole, 9,9′-bis(1,1′-biphenyl-3-yl)-3,3′-bi-9H-carbazole, 9-(1,1′-biphenyl-3-yl)-9′-(1,1′-biphenyl-4-yl)-9H,9′H-3,3′-bicarbazole (abbreviation: mBPCCBP), and 9-(2-naphthyl)-9′-phenyl-9H,9′H-3,3′-bicarbazole (abbreviation: βNCCP).

[0177] Specific examples of aromatic amines having a carbazolyl group include 4-phenyl-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBA1BP), N-(4-biphenyl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-9-phenyl-9H-carbazol-3-amine (abbreviation: PCBiF), N-(1,1'-biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9-dimethyl-9H-fluoren- PCBBiF, 4,4'-diphenyl-4''-(9-phenyl-9H-carbazol-3-yl)triphenylamine (PCBBiBP), 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (PCBANB), 4,4'-di(1-naphthyl)-4''-(9-phenyl-9H-carbazol-3-yl)triphenylamine (PCBNBB), 4-phenyldiphenyl-(9-phenyl-9H-carbazol-3-yl)triphenylamine (PCBBiB ... N,N'-bis(9-phenylcarbazol-3-yl)-N,N'-diphenylbenzene-1,3-diamine (abbreviation: PCA2B), N,N',N''-triphenyl-N,N',N''-tris(9-phenylcarbazol-3-yl)benzene-1,3,5-triamine (abbreviation: PCA3B), 9,9-dimethyl-N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]fluoren-2-amine (abbreviation: PCBAF), N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]spiro-9,9'-bifluoren-2-amine (abbreviation: PCBASF), PCzPCA1, PCzPCA2, PCzPCN1, 3-[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA1), 3,6-bis[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA2), 3,Examples include 6-bis[N-(4-diphenylaminophenyl)-N-(1-naphthyl)amino]-9-phenylcarbazole (abbreviation: PCzTPN2), 2-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]spiro-9,9'-bifluorene (abbreviation: PCASF), N-[4-(9H-carbazol-9-yl)phenyl]-N-(4-phenyl)phenylaniline (abbreviation: YGA1BP), N,N'-bis[4-(carbazol-9-yl)phenyl]-N,N'-diphenyl-9,9-dimethylfluorene-2,7-diamine (abbreviation: YGA2F), and 4,4',4''-tris(carbazol-9-yl)triphenylamine (abbreviation: TCTA).

[0178] In addition to the above, examples of carbazole derivatives include 3-[4-(9-phenanthryl)-phenyl]-9-phenyl-9H-carbazole (abbreviation: PCPPn), 3-[4-(1-naphthyl)-phenyl]-9-phenyl-9H-carbazole (abbreviation: PCPN), 1,3-bis(N-carbazolyl)benzene (abbreviation: mCP), 4,4'-di(N-carbazolyl)biphenyl (abbreviation: CBP), 3,6-bis(3,5-diphenylphenyl)-9-phenylcarbazole (abbreviation: CzTP), 1,3,5-tris[4-(N-carbazolyl)phenyl]benzene (abbreviation: TCPB), and 9-[4-(10-phenyl-9-anthracenyl)phenyl]-9H-carbazole (abbreviation: CzPA).

[0179] Specific examples of thiophene derivatives (compounds having a thiophene skeleton) and furan derivatives (compounds having a furan skeleton) include compounds having a thiophene skeleton such as 4,4′,4″-(benzene-1,3,5-triyl)tri(dibenzothiophene) (abbreviation: DBT3P-II), 2,8-diphenyl-4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]dibenzothiophene (abbreviation: DBTFLP-III), and 4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]-6-phenyldibenzothiophene (abbreviation: DBTFLP-IV), as well as 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).

[0180] Specific examples of aromatic amines include 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB or α-NPD), N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (abbreviation: TPD), 4,4'-bis[N-(spiro-9,9'-bifluoren-2-yl)-N-phenylamino]biphenyl (abbreviation: :BSPB), 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP), 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) 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), TDATA, m-MTDATA, N,N'-di(p-tolyl)-N,N'-diphenyl-p-phenylenediamine (abbreviation: DTDPPA), DPAB, DNTPD, DPA3B, and the like.

[0181] As the hole transporting material, polymer compounds such as PVK, PVTPA, PTPDMA, and Poly-TPD can also be used.

[0182] The hole transporting material is not limited to the above, and various known materials can be used for the hole injection layer 111 and the hole transport layer 112 either singly or in combination.

[0183] <Light-emitting layer> The light-emitting layer 113 is a layer containing a light-emitting substance. The light-emitting layer 113 can have one or more types of light-emitting substances. As the light-emitting substance, a substance that emits light of a color such as blue, purple, blue-purple, green, yellow-green, yellow, orange, or red is appropriately used. Furthermore, a substance that emits near-infrared light can also be used as the light-emitting substance. Furthermore, by using different light-emitting substances in the multiple light-emitting layers, a structure that emits different light colors (for example, white light obtained by combining light-emitting colors that are complementary to each other) can be obtained. Furthermore, a stacked structure in which one light-emitting layer contains different light-emitting substances may be used.

[0184] The light-emitting layer 113 preferably contains one or more organic compounds (host materials, assist materials, and the like) in addition to a light-emitting substance (guest material). The light-emitting device of one embodiment of the present invention preferably contains the organic compound of one embodiment of the present invention described in Embodiment 1 as one or more organic compounds. As the one or more organic compounds, one or both of a hole-transporting material and an electron-transporting material described in this embodiment can be used. As the one or more organic compounds, a bipolar material may be used.

[0185] The light-emitting substance that can be used in the light-emitting layer 113 is not particularly limited, and a light-emitting substance that converts singlet excitation energy into light emission in the visible light region or near-infrared light region, or a light-emitting substance that converts triplet excitation energy into light emission in the visible light region or near-infrared light region can be used.

[0186] Examples of luminescent substances that convert singlet excitation energy into luminescence include fluorescent substances (fluorescent materials), such as pyrene derivatives, anthracene derivatives, triphenylene derivatives, fluorene derivatives, carbazole derivatives, dibenzothiophene derivatives, dibenzofuran derivatives, dibenzoquinoxaline derivatives, quinoxaline derivatives, pyridine derivatives, pyrimidine derivatives, phenanthrene derivatives, naphthalene derivatives, etc. Pyrene derivatives are particularly preferred because of their 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), N,N'-bis(dibenzothiophen-2-yl)-N, 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), N,N'-(pyrene-1,6-diyl)bis[(6,N-diphenylbenzo[b]naphtho[1,2-d]furan)-8-amine] (abbreviation: 1,6BnfAPrn-03), and the like.

[0187] Other compounds include 5,6-bis[4-(10-phenyl-9-anthryl)phenyl]-2,2'-bipyridine (abbreviation: PAP2BPy), 5,6-bis[4'-(10-phenyl-9-anthryl)biphenyl-4-yl]-2,2'-bipyridine (abbreviation: PAPP2BPy), N,N'-bis[4-(9H-carbazol-9-yl)phenyl]-N,N'-diphenylstilbene-4,4'-diamine (abbreviation: YGA2S), 4-(9H-carbazol-9-yl)phenyl N,9-diphenyl-N-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: PCAPA), 4-(10-phenyl-9-anthryl)-4'-(9,10-diphenyl-2-anthryl)triphenylamine (abbreviation: YGAPA), 4-(9H-carbazol-9-yl)-4'-(9,10-diphenyl-2-anthryl)triphenylamine (abbreviation: 2YGAPPA), N,9-diphenyl-N-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: PCAPA), 4-(10-phenyl-9-anthryl)-4' -(9-Phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBAPA), 4-[4-(10-phenyl-9-anthryl)phenyl]-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBAPBA), perylene, 2,5,8,11-tetra(tert-butyl)perylene (abbreviation: TBP), N,N''-(2-tert-butylanthracene-9,10-diyldi-4,1-phenyl)-4-[4-(10-phenyl-9-anthryl)phenyl]-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBAPBA), perylene, N,9-diphenyl-N-[4-(9,10-diphenyl-2-anthryl)phenyl]-9H-carbazole-3-amine (abbreviation: 2PCAPPA), N-[4-(9,10-diphenyl-2-anthryl)phenyl]-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPPA), and the like can be used.

[0188] Furthermore, examples of light-emitting substances that convert triplet excitation energy into luminescence include phosphorescent substances (phosphorescent materials) and thermally activated delayed fluorescence (TADF) materials that exhibit thermally activated delayed fluorescence.

[0189] Examples of phosphorescent materials include organometallic complexes, metal complexes (platinum complexes), rare earth metal complexes, etc. These materials emit different luminescent colors (emission peaks), so they can be appropriately selected and used as needed.

[0190] Examples of phosphorescent materials that exhibit blue or green and have an emission spectrum with a peak wavelength of 450 nm or more and 570 nm or less include the following substances.

[0191] For example, tris{2-[5-(2-methylphenyl)-4-(2,6-dimethylphenyl)-4H-1,2,4-triazol-3-yl-κN2]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 organometallic complexes with a 4H-triazole skeleton, such as tris[3-(5-biphenyl)-5-isopropyl-4-phenyl-4H-1,2,4-triazolato]iridium(III) (abbreviation: [Ir(iPrptz-3b)3]), tris[3-(5-biphenyl)-5-isopropyl-4-phenyl-4H-1,2,4-triazolato]iridium(III) (abbreviation: Ir(iPr5btz)3]), organometallic complexes with a 1H-triazole skeleton, such as fac-tris[1-(2,6-diisopropylphenyl)-5-phenyl-1H-1,2,4-triazolato]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]); organometallic complexes with an imidazole skeleton, such as tris[3-(2,6-dimethylphenyl)-7-methylimidazo[1,2-f]phenanthridinato]iridium(III) (abbreviation: [Ir(iPrpmi)3]), tris[3-(2,6-dimethylphenyl)-7-methylimidazo[1,2-f]phenanthridinato]iridium(III) (abbreviation: [Ir(dmpimpt-Me)3]), and bis[2-(4',6'-difluorophenyl)pyridinato-N,C 2’]iridium(III) tetrakis(1-pyrazolyl)borate (abbreviation: FIr6), bis[2-(4',6'-difluorophenyl)pyridinato-N,C 2’ ]iridium(III) picolinate (abbreviation: FIrpic), bis{2-[3',5'-bis(trifluoromethyl)phenyl]pyridinato-N,C 2’}iridium(III) picolinate (abbreviation: [Ir(CF3ppy)2(pic)]), bis[2-(4',6'-difluorophenyl)pyridinato-N,C 2’ ] Organometallic complexes with a phenylpyridine derivative having an electron-withdrawing group as a ligand, such as iridium(III) acetylacetonate (abbreviation: FIr(acac)), are also included.

[0192] Examples of phosphorescent materials that exhibit green or yellow and have an emission spectrum with a peak wavelength of 495 nm or more and 590 nm or less include the following substances.

[0193] 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-butyl-4-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mppm)2(acac)]), (acetylacetonato)bis[6-(2-norbornyl)-4-phenylpyrimidinato]iridium(III) (abbreviation: [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) 2(acac)]), (acetylacetonato)bis{4,6-dimethyl-2-[6-(2,6-dimethylphenyl)-4-pyrimidinyl-κN3]phenyl-κC}iridium(III) (abbreviation: [Ir(dmppm-dmp)2(acac)]), and (acetylacetonato)bis(4,6-diphenylpyrimidinato)iridium(III) (abbreviation: [Ir(dppm)2(acac)]). iridium complexes, organometallic iridium complexes with a pyrazine skeleton such as (acetylacetonato)bis(3,5-dimethyl-2-phenylpyrazinato)iridium(III) (abbreviation: [Ir(mppr-Me)2(acac)]) and (acetylacetonato)bis(5-isopropyl-3-methyl-2-phenylpyrazinato)iridium(III) (abbreviation: [Ir(mppr-iPr)2(acac)]), tris(2-phenylpyridinato-N,C 2’ ) Iridium(III) (abbreviation: [Ir(ppy)3]), bis(2-phenylpyridinato-N,C 2’) Iridium(III) acetylacetonate (abbreviation: [Ir(ppy)2(acac)]), bis(benzo[h]quinolinato)iridium(III) acetylacetonate (abbreviation: [Ir(bzq)2(acac)]), tris(benzo[h]quinolinato)iridium(III) (abbreviation: [Ir(bzq)3]), tris(2-phenylquinolinato-N,C 2’ ) Iridium(III) (abbreviation: [Ir(pq)3]), bis(2-phenylquinolinato-N,C 2’ Organometallic iridium complexes with a pyridine skeleton, such as iridium(III) acetylacetonate (abbreviation: [Ir(pq)2(acac)]), [2-(4-phenyl-2-pyridinyl-κN)phenyl-κC]bis[2-(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], and bis(2,4-diphenyl-1,3-oxazolato-N,C) 2’ ) Iridium(III) acetylacetonate (abbreviation: [Ir(dpo)2(acac)]), bis{2-[4'-(perfluorophenyl)phenyl]pyridinato-N,C 2’}Iridium(III) acetylacetonate (abbreviation: [Ir(p-PF-ph)2(acac)]), bis(2-phenylbenzothiazolato-N,C 2’ ) iridium(III) acetylacetonate (abbreviated as [Ir(bt)2(acac)]), as well as rare earth metal complexes such as tris(acetylacetonato)(monophenanthroline)terbium(III) (abbreviated as [Tb(acac)3(Phen)]).

[0194] Examples of phosphorescent materials that exhibit yellow or red and have an emission spectrum with a peak wavelength of 570 nm or more and 750 nm or less include the following substances.

[0195] 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)]), bis[4,6-di(naphthalen-1-yl)pyrimidinato](dipivaloylmethanato)iridium(III) (abbreviation: [Ir(d1npm)2(dpm)]), tris(4-t-butyl-6-phenylpyrimidinato)iridium(III) Organometallic complexes with pyrimidine skeletons such as (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)]), and bis{4,6-dimethyl-2-[3-(3,5-dimethylphenyl)-5-phenyl-2-pyrazinyl-κN]phenyl-κC}(2,6-dimethyl-3,5-heptanedionato-κC). 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-pyrazinyl-κN]phenyl-κC}(2,2,6,6-tetramethyl-3,5-heptanedionato-κ) 2 O,O')iridium(III) (abbreviation: [Ir(dmdppr-dmCP)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’)iridium(III) (abbreviation: [Ir(dpq)2(acac)]), (acetylacetonato)bis[2,3-bis(4-fluorophenyl)quinoxalinato]iridium(III) (abbreviation: [Ir(Fdpq)2(acac)]), bis{4,6-dimethyl-2-[5-(5-cyano-2-methylphenyl)-3-(3,5-dimethylphenyl)-2-pyrazinyl-κN]phenyl-κC}(2,2,6,6-tetramethyl-3,5-heptanedionato-κ2O,O')iridium(III) (abbreviation: [Ir(dmdppr-m5CP)2(dpm)]), and other organometallic complexes with a pyrazine skeleton, such as 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 These include organometallic complexes with a pyridine skeleton, such as (O,O')iridium(III), platinum complexes such as 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrinplatinum(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-thenoyl)-3,3,3-trifluoroacetonato](monophenanthroline)europium(III) (abbreviation: [Eu(TTA)3(Phen)]).

[0196] As the organic compound (host material, assist material, etc.) used in the light-emitting layer 113, one or more substances having an energy gap larger than the energy gap of the light-emitting substance can be selected and used.

[0197] When the light-emitting substance used in the light-emitting layer 113 is a fluorescent material, an organic compound that has a high energy level in a singlet excited state and a low energy level in a triplet excited state is preferably used as the organic compound used in combination with the light-emitting substance.

[0198] Although some of the examples overlap with the above examples, specific examples of organic compounds are shown below from the viewpoint of preferable combinations with light-emitting substances (fluorescent materials, phosphorescent materials).

[0199] When the luminescent substance is a fluorescent material, examples of organic compounds that can be used in combination with the luminescent substance include condensed polycyclic aromatic compounds such as anthracene derivatives, tetracene derivatives, phenanthrene derivatives, pyrene derivatives, chrysene derivatives, and dibenzo[g,p]chrysene derivatives.

[0200] Specific examples of organic compounds (host materials) used in combination with fluorescent materials include 9-phenyl-3-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviation: PCzPA), 3,6-diphenyl-9-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviation: DPCzPA), PCPN, 9,10-diphenylanthracene (abbreviation: DPAnth), and N,N-diphenyl-9-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: CzA1PA). , 4-(10-phenyl-9-anthryl)triphenylamine (abbreviation: DPhPA), 4-(9H-carbazol-9-yl)-4'-(10-phenyl-9-anthryl)triphenylamine (abbreviation: YGAPA), N,9-diphenyl-N-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: PCAPA), N,9-diphenyl-N-{4-[4-(10-phenyl-9-anthryl)phenyl]phenyl}-9H-carbazol-3-amine (abbreviation: PCAPBA), N-(9,10-diphenyl) (phenyl-2-anthryl)-N,9-diphenyl-9H-carbazol-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), CzPA, 7-[4-(10-phenyl-9-anthryl)phenyl]-7H-dibenzo[c,g]carbazole (abbreviation: cgDBCzPA), 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), 9,9'-bianthryl (abbreviation: BANT), 9,9'-(stilbene-3,Examples include 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.

[0201] When the light-emitting substance is a phosphorescent material, an organic compound having a triplet excitation energy greater than the triplet excitation energy (energy difference between the ground state and the triplet excited state) of the light-emitting substance can be selected as the organic compound to be used in combination with the light-emitting substance.

[0202] When a plurality of organic compounds (e.g., a first host material and a second host material (or assist material)) are used in combination with a light-emitting substance to form an exciplex, it is preferable to use these plurality of organic compounds in combination with a phosphorescent material (particularly an organometallic complex).

[0203] With such a structure, light emission can be efficiently obtained using Exciplex-Triplet Energy Transfer (ExTET), which is energy transfer from an exciplex to a light-emitting substance. A combination of multiple organic compounds is preferably one that easily forms an exciplex, and it is particularly preferable to combine a compound that easily accepts holes (hole-transporting material) with a compound that easily accepts electrons (electron-transporting material). The organic compound of one embodiment of the present invention described in Embodiment 1 has a low LUMO level and is suitable as a compound that easily accepts electrons. Specific examples of the hole-transporting material and the electron-transporting material include the materials described in this embodiment. With this structure, high efficiency, low-voltage operation, and a long lifetime of a light-emitting device can be simultaneously achieved.

[0204] When the luminescent substance is a phosphorescent material, examples of organic compounds that can be used in combination with the luminescent substance include aromatic amines, carbazole derivatives, dibenzothiophene derivatives, dibenzofuran derivatives, zinc- or aluminum-based metal complexes, oxadiazole derivatives, triazole derivatives, benzimidazole derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, pyrimidine derivatives, triazine derivatives, pyridine derivatives, bipyridine derivatives, and phenanthroline derivatives.

[0205] Among the above, specific examples of the aromatic amines (compounds having an aromatic amine skeleton), carbazole derivatives, dibenzothiophene derivatives (thiophene derivatives), and dibenzofuran derivatives (furan derivatives), which are organic compounds with high hole-transporting properties, are the same as the specific examples of the hole-transporting materials shown above.

[0206] Specific examples of zinc- or aluminum-based metal complexes, which are organic compounds with high electron-transporting properties, include metal complexes having a quinoline skeleton or a benzoquinoline skeleton, such as tris(8-quinolinolato)aluminum(III) (abbreviation: Alq), tris(4-methyl-8-quinolinolato)aluminum(III) (abbreviation: Almq3), bis(10-hydroxybenzo[h]quinolinato)beryllium(II) (abbreviation: BeBq2), bis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum(III) (abbreviation: BAlq), and bis(8-quinolinolato)zinc(II) (abbreviation: Znq).

[0207] In addition, metal complexes having oxazole or thiazole ligands, such as bis[2-(2-benzoxazolyl)phenolato]zinc(II) (abbreviation: ZnPBO) and bis[2-(2-benzothiazolyl)phenolato]zinc(II) (abbreviation: ZnBTZ), can also be used.

[0208] Specific examples of organic compounds with high electron transport properties, such as oxadiazole derivatives, triazole derivatives, benzimidazole derivatives, quinoxaline derivatives, dibenzoquinoxaline 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-oxadiazol-2-yl]benzene (abbreviation: OXD-7), 9-[4-(5-phenyl-1 ,3,4-oxadiazol-2-yl)phenyl]-9H-carbazole (abbreviation: CO11), 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (abbreviation: TAZ), 3-(4-tert-butylphenyl)-4-(4-ethylphenyl)-5-(4-biphenylyl)-1,2,4-triazole (abbreviation: p-EtTAZ), 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), 4,4'-bis(5-methylbenzoxazol-2-yl)stilbene (abbreviation: BzOs), bathophenanthroline (abbreviation: Bphen), bathocuproine (abbreviation: BCP), 2,9-bis(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBphen), 2-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBT PDBq-II), 2-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviated as 2mDBTBPDBq-II), 2-[3'-(9H-carbazol-9-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviated as 2mCzBPDBq), 2-[4-(3,6-diphenyl-9H-carbazol-9-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviated as 2CzPDBq-III), 7-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviated as 7mDBTPDBq-II), and 6-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviated as 6mDBTPDBq-II).

[0209] Specific examples of heterocyclic compounds having a diazine skeleton, heterocyclic compounds having a triazine skeleton, and heterocyclic compounds having a pyridine skeleton, which are organic compounds with high electron transport properties, include 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-carbazol-9-yl)phenyl]pyrimidine (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-carbazole (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), and the like.

[0210] As organic compounds with high electron transport properties, polymer compounds such as poly(2,5-pyridinediyl) (abbreviation: PPy), poly[(9,9-dihexylfluorene-2,7-diyl)-co-(pyridine-3,5-diyl)] (abbreviation: PF-Py), and poly[(9,9-dioctylfluorene-2,7-diyl)-co-(2,2'-bipyridine-6,6'-diyl)] (abbreviation: PF-BPy) can also be used.

[0211] TADF materials are materials that can upconvert (reverse intersystem crossing) a triplet excited state to a singlet excited state with a small amount of thermal energy, and efficiently emit light (fluorescence) from the singlet excited state. The conditions for efficiently obtaining thermally activated delayed fluorescence include an energy difference between the triplet excited level and the singlet excited level of 0 eV or more and 0.2 eV or less, preferably 0 eV or more and 0.1 eV or less. The delayed fluorescence in TADF materials refers to light emission that has a spectrum similar to that of normal fluorescence but has a significantly long lifetime. The lifetime is approximately 10 -6 seconds or more, preferably 10 -3 More than a second.

[0212] Examples of TADF materials include fullerenes and their derivatives, acridine derivatives such as proflavine, eosin, etc. Also included are metal-containing porphyrins containing magnesium (Mg), zinc (Zn), cadmium (Cd), tin (Sn), platinum (Pt), indium (In), or palladium (Pd). Examples of metal-containing porphyrins include protoporphyrin-tin fluoride complex (abbreviation: SnF2(Proto IX)), mesoporphyrin-tin fluoride complex (abbreviation: SnF2(Meso IX)), hematoporphyrin-tin fluoride complex (abbreviation: SnF2(Hemato IX)), coproporphyrin tetramethyl ester-tin fluoride complex (abbreviation: SnF2(Copro III-4Me)), octaethylporphyrin-tin fluoride complex (abbreviation: SnF2(OEP)), etioporphyrin-tin fluoride complex (abbreviation: SnF2(Etio I)), and octaethylporphyrin-platinum chloride complex (abbreviation: PtCl2OEP).

[0213] Other examples include 2-(biphenyl-4-yl)-4,6-bis(12-phenylindolo[2,3-a]carbazol-11-yl)-1,3,5-triazine (abbreviated as PIC-TRZ), PCCzPTzn, 2-[4-(10H-phenoxazin-10-yl)phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviated as PXZ-TRZ), 3-[4-(5-phenyl-5,10-dihydrophenazin-10-yl)phenyl]-4,5-diphenyl-1,2,4-triazole (abbreviated as PXZ-TRZ), and Heterocyclic compounds having a π-electron-rich heteroaromatic ring and a π-electron-deficient heteroaromatic ring can be used, such as bis[4-(9,9-dimethyl-9,10-dihydroacridine)phenyl]sulfone (abbreviation: DMAC-DPS), and 10-phenyl-10H,10'H-spiro[acridine-9,9'-anthracene]-10'-one (abbreviation: ACRSA). Substances in which a π-electron-rich heteroaromatic ring and a π-electron-deficient heteroaromatic ring are directly bonded are particularly preferred because the donor properties of the π-electron-rich heteroaromatic ring and the acceptor properties of the π-electron-deficient heteroaromatic ring are both enhanced, resulting in a smaller energy difference between the singlet excited state and the triplet excited state.

[0214] When a TADF material is used, it can be used in combination with other organic compounds, particularly the host material, hole transport material, and electron transport material described above.

[0215] Furthermore, the above materials can be used in combination with low-molecular-weight materials or high-molecular-weight materials to form the light-emitting layer 113. For film formation, known methods (such as vapor deposition, coating, or printing) can be used as appropriate.

[0216] <Electron transport layer> The electron transport layer 114 is a layer that transports electrons injected from the second electrode 102 by the electron injection layer 115 to the light-emitting layer 113. The electron transport layer 114 is a layer that contains an electron transporting material. The electron transporting material used for the electron transport layer 114 is 1×10 -6 cm2 A substance having an electron mobility of 1 / Vs or higher is preferred. Note that other substances can also be used as long as they have a higher electron-transporting property than hole-transporting property. The light-emitting device of one embodiment of the present invention preferably includes the organic compound of one embodiment of the present invention as an electron-transporting material used in the electron-transport layer 114.

[0217] Examples of the electron-transporting material that can be used include metal complexes having a quinoline skeleton, metal complexes having a benzoquinoline skeleton, metal complexes having an oxazole skeleton, and metal complexes having a thiazole skeleton, as well as materials with high electron-transporting properties, such as oxadiazole derivatives, triazole derivatives, imidazole derivatives, oxazole derivatives, thiazole derivatives, phenanthroline derivatives, quinoline derivatives having a quinoline ligand, benzoquinoline derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, and π-electron-deficient heteroaromatic compounds including nitrogen-containing heteroaromatic compounds.

[0218] As specific examples of the electron transporting material, the materials shown above can be used.

[0219] <Electron injection layer> The electron injection layer 115 is a layer containing a material with high electron injection properties. The electron injection layer 115 may contain lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF), lithium oxide (LiO x ) or an alkaline earth metal, or a compound thereof, can be used. Also, a rare earth metal compound such as erbium fluoride (ErF3) can be used. Furthermore, an electride can be used for the electron injection layer 115. For example, an electride can be a substance in which a mixed oxide of calcium and aluminum is doped with electrons at a high concentration. Note that the above-mentioned substance constituting the electron transport layer 114 can also be used.

[0220] The electron-injection layer 115 may also be formed using a composite material containing an electron-transporting material and a donor material (electron-donating material). Such a composite material has excellent electron-injecting and electron-transporting properties because electrons are generated in the organic compound by the electron donor. In this case, the organic compound is preferably a material that is excellent in transporting the generated electrons. Specifically, the electron-transporting materials (metal complexes, heteroaromatic compounds, etc.) used in the electron-transporting layer 114 described above can be used. The electron donor may 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 preferred, such as lithium oxide, calcium oxide, and barium oxide. A Lewis base such as magnesium oxide can also be used. An organic compound such as tetrathiafulvalene (TTF) can also be used.

[0221] <Charge generation layer> In the light-emitting device shown in FIG. 1C, the charge generation layer 104 has the function of injecting electrons into the EL layer 103a and injecting holes into the EL layer 103b when a voltage is applied between the first electrode 101 (anode) and the second electrode 102 (cathode).

[0222] The charge generation layer 104 may be configured to contain a hole transport material and an acceptor material (electron acceptor material), or may be configured to contain an electron transport material and a donor material. By forming the charge generation layer 104 with such a configuration, it is possible to suppress an increase in driving voltage when an EL layer is stacked.

[0223] The hole transporting material, the acceptor material, the electron transporting material, and the donor material may be the same as those described above.

[0224] The light-emitting device described in this embodiment can be fabricated by a vacuum process such as vapor deposition or a solution process such as spin coating or inkjet printing. When a vapor deposition method is used, a physical vapor deposition (PVD) method such as sputtering, ion plating, ion beam deposition, molecular beam deposition, or vacuum deposition, or a chemical vapor deposition (CVD) method can be used. In particular, the functional layers (hole injection layer, hole transport layer, light-emitting layer, electron transport layer, electron injection layer) and the charge generation layer included in the EL layer can be formed by a vapor deposition method (vacuum deposition, etc.), a coating method (dip coating, die coating, bar coating, spin coating, spray coating, etc.), a printing method (inkjet printing, screen (stencil printing), offset (lithographic printing), flexography (relief printing), gravure printing, microcontact printing, etc.), or the like.

[0225] The materials of the functional layer and charge generation layer constituting the EL layer 103 are not limited to the above-mentioned materials. For example, the functional layer may be made of a high molecular weight compound (oligomer, dendrimer, polymer, etc.), a medium molecular weight compound (a compound in the intermediate range between a low molecular weight and a high molecular weight: molecular weight of 400 to 4000), an inorganic compound (quantum dot material, etc.), etc. The quantum dot material may be a colloidal quantum dot material, an alloy quantum dot material, a core-shell quantum dot material, a core quantum dot material, etc.

[0226] This embodiment mode can be combined with other embodiment modes as appropriate.

[0227] (Embodiment 3) In this embodiment, a light-emitting device according to one embodiment of the present invention will be described with reference to FIGS.

[0228] [Configuration example 1 of light-emitting device] Fig. 2A shows a top view of the light emitting device, and Fig. 2B and Fig. 2C show cross-sectional views taken along dashed lines X1-Y1 and X2-Y2 in Fig. 2A. The light emitting device shown in Fig. 2A to Fig. 2C can be used, for example, in a lighting device. The light emitting device may be a bottom emission, top emission, or dual emission device.

[0229] The light-emitting device shown in FIG. 2B includes a substrate 490a, a substrate 490b, a conductive layer 406, a conductive layer 416, an insulating layer 405, an organic EL device 450 (a first electrode 401, an EL layer 402, and a second electrode 403), and an adhesive layer 407. The organic EL device 450 can also be called a light-emitting element, an organic EL element, a light-emitting device, or the like. The EL layer 402 preferably includes the organic compound of one embodiment of the present invention described in Embodiment 1. For example, the organic compound is preferably included as one or both of a host material of the light-emitting layer and a material of the electron-transport layer.

[0230] Organic EL device 450 has a first electrode 401 on a substrate 490a, an EL layer 402 on the first electrode 401, and a second electrode 403 on the EL layer 402. Organic EL device 450 is encapsulated by substrate 490a, adhesive layer 407, and substrate 490b.

[0231] The ends of the first electrode 401, the conductive layer 406, and the conductive layer 416 are covered with an insulating layer 405. The conductive layer 406 is electrically connected to the first electrode 401, and the conductive layer 416 is electrically connected to the second electrode 403. The conductive layer 406, covered with the insulating layer 405 via the first electrode 401, functions as an auxiliary wiring and is electrically connected to the first electrode 401. Having an auxiliary wiring electrically connected to the electrode of the organic EL device 450 is preferable because it can suppress voltage drops caused by electrode resistance. The conductive layer 406 may be provided on the first electrode 401. Furthermore, an auxiliary wiring electrically connected to the second electrode 403 may be provided on the insulating layer 405 or the like.

[0232] The substrate 490a and the substrate 490b can each be made of glass, quartz, ceramic, sapphire, organic resin, etc. Using a flexible material for the substrate 490a and the substrate 490b can increase the flexibility of the display device.

[0233] The light-emitting surface of the light-emitting device may be provided with a light extraction structure to increase the light extraction efficiency, an antistatic film to prevent dust from adhering, a water-repellent film to prevent dirt from adhering, a hard coat film to prevent scratches from occurring during use, an impact absorbing layer, etc.

[0234] Examples of insulating materials that can be used for the insulating layer 405 include resins such as acrylic resins and epoxy resins, and inorganic insulating materials such as silicon oxide, silicon oxynitride, silicon nitride oxide, silicon nitride, and aluminum oxide.

[0235] The adhesive layer 407 can be made of various curable adhesives, such as a photo-curable adhesive (e.g., an ultraviolet curable adhesive), a reactive curable adhesive, a thermosetting adhesive, or an anaerobic adhesive. Examples of such adhesives include epoxy resin, acrylic resin, silicone resin, phenolic resin, polyimide resin, imide resin, PVC (polyvinyl chloride) resin, PVB (polyvinyl butyral) resin, and EVA (ethylene vinyl acetate) resin. In particular, a material with low moisture permeability, such as epoxy resin, is preferable. Alternatively, a two-component resin may be used. Alternatively, an adhesive sheet or the like may be used.

[0236] The light-emitting device shown in FIG. 2C includes barrier layer 490c, conductive layer 406, conductive layer 416, insulating layer 405, organic EL device 450, adhesive layer 407, barrier layer 423, and substrate 490b.

[0237] Barrier layer 490c shown in FIG. 2C includes substrate 420, adhesive layer 422, and insulating layer 424 with high barrier properties.

[0238] 2C, organic EL device 450 is disposed between insulating layer 424 with high barrier properties and barrier layer 423. Therefore, even if a resin film with relatively low waterproof properties is used for substrate 420 and substrate 490b, it is possible to prevent impurities such as water from entering the organic EL device and shortening its lifespan.

[0239] Substrate 420 and substrate 490b may each be made of, for example, polyester resin such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN), polyacrylonitrile resin, acrylic resin, polyimide resin, polymethyl methacrylate resin, polycarbonate (PC) resin, polyethersulfone (PES) resin, polyamide resin (nylon, aramid, etc.), polysiloxane resin, cycloolefin resin, polystyrene resin, polyamideimide resin, polyurethane resin, polyvinyl chloride resin, polyvinylidene chloride resin, polypropylene resin, polytetrafluoroethylene (PTFE) resin, ABS resin, cellulose nanofiber, etc. Substrate 420 and substrate 490b may also be made of glass having a thickness sufficient to provide flexibility.

[0240] An inorganic insulating film is preferably used as the insulating layer 424 having high barrier properties. Examples of the inorganic insulating film that can be used include a silicon nitride film, a silicon oxynitride film, a silicon oxide film, a silicon nitride oxide film, an aluminum oxide film, and an aluminum nitride film. Alternatively, a hafnium oxide film, an yttrium oxide film, a zirconium oxide film, a gallium oxide film, a tantalum oxide film, a magnesium oxide film, a lanthanum oxide film, a cerium oxide film, and a neodymium oxide film may also be used. Two or more of the above insulating films may be stacked.

[0241] The barrier layer 423 preferably has at least one inorganic film. For example, the barrier layer 423 can have a single inorganic film structure or a laminated structure of an inorganic film and an organic film. The inorganic insulating film described above is suitable as the inorganic film. An example of the laminated structure is a structure in which a silicon oxynitride film, a silicon oxide film, an organic film, a silicon oxide film, and a silicon nitride film are formed in this order. By forming the protective layer into a laminated structure of an inorganic film and an organic film, impurities (typically, hydrogen, water, etc.) that may enter the organic EL device 450 can be suitably suppressed.

[0242] The insulating layer 424 and the organic EL device 450, which have high barrier properties, can be formed directly on a flexible substrate 420. In this case, the adhesive layer 422 is not necessary. Alternatively, the insulating layer 424 and the organic EL device 450 can be formed on a rigid substrate via a release layer and then transferred to the substrate 420. For example, the release layer may be applied with heat, force, laser light, or the like to peel the insulating layer 424 and the organic EL device 450 from the rigid substrate, and then the substrate 420 may be attached using the adhesive layer 422 to transfer the insulating layer to the substrate 420. Examples of the release layer include a laminated structure of inorganic films including a tungsten film and a silicon oxide film, and organic resin films such as polyimide. When a rigid substrate is used, the insulating layer 424 can be formed at a higher temperature than when a resin substrate is used, resulting in a dense insulating film with extremely high barrier properties.

[0243] [Configuration example 2 of light-emitting device] A cross-sectional view of a light-emitting device is shown in Fig. 3A. The light-emitting device shown in Fig. 3A is an active matrix light-emitting device in which a transistor and a light-emitting device are electrically connected to each other.

[0244] The light emitting device shown in FIG. 3A includes a substrate 201, a transistor 210, a light emitting device 203R, a light emitting device 203G, a light emitting device 203B, a color filter 206R, a color filter 206G, a color filter 206B, a substrate 205, and the like.

[0245] In FIG. 3A, a transistor 210 is provided on a substrate 201, an insulating layer 202 is provided on the transistor 210, and light-emitting devices 203R, 203G, and 203B are provided on the insulating layer 202.

[0246] The transistor 210 and the light emitting devices 203R, 203G, and 203B are sealed in a space 207 surrounded by the substrate 201, the substrate 205, and the adhesive layer 208. The space 207 may be filled with, for example, a reduced pressure atmosphere, an inert atmosphere, or a resin.

[0247] The light emitting device shown in FIG. 3A has a configuration in which one pixel has a red sub-pixel (R), a green sub-pixel (G), and a blue sub-pixel (B).

[0248] A light-emitting device according to one embodiment of the present invention has a plurality of pixels arranged in a matrix. Each pixel has one or more sub-pixels. Each sub-pixel has one light-emitting device. For example, the pixel may have three sub-pixels (e.g., three colors of R, G, and B, or three colors of yellow (Y), cyan (C), and magenta (M)) or four sub-pixels (e.g., four colors of R, G, B, and white (W), or four colors of R, G, B, and Y).

[0249] 3B shows detailed structures of light-emitting device 203R, light-emitting device 203G, and light-emitting device 203B. Light-emitting devices 203R, 203G, and 203B share a common EL layer 213 and have a microcavity structure in which the optical distance between electrodes of each light-emitting device is adjusted according to the emission color of the light-emitting device. The EL layer 213 preferably contains the organic compound according to one embodiment of the present invention described in Embodiment 1. For example, the organic compound is preferably contained as one or both of the host material of the light-emitting layer and the material of the electron-transport layer.

[0250] The first electrode 211 functions as a reflective electrode, and the second electrode 215 functions as a semi-transmissive and semi-reflective electrode.

[0251] Light emitting device 203R is adjusted so that the optical distance between first electrode 211 and second electrode 215 is 220R to enhance the intensity of red light. Similarly, light emitting device 203G is adjusted so that the optical distance between first electrode 211 and second electrode 215 is 220G to enhance the intensity of green light, and light emitting device 203B is adjusted so that the optical distance between first electrode 211 and second electrode 215 is 220B to enhance the intensity of blue light.

[0252] 3B, optical adjustment can be performed by forming conductive layer 212R on first electrode 211 in light-emitting device 203R, and by forming conductive layer 212G on first electrode 211 in light-emitting device 203G. Furthermore, in light-emitting device 203B, a conductive layer having a thickness different from that of conductive layer 212R and conductive layer 212G may be formed on first electrode 211 to adjust optical distance 220B. Note that, as shown in FIG. 3A, ends of first electrode 211, conductive layer 212R, and conductive layer 212G are covered with insulating layer 204.

[0253] 3A is a top-emission type light-emitting device in which light emitted from a light-emitting device is emitted through color filters of various colors formed on substrate 205. The color filters can pass specific wavelength ranges of visible light and block specific wavelength ranges.

[0254] In the red sub-pixel (R), light emitted from the light-emitting device 203R is output through a red color filter 206R. As shown in Fig. 3A, by providing a color filter 206R that transmits only light in the red wavelength range at a position overlapping the light-emitting device 203R, red light can be emitted from the light-emitting device 203R.

[0255] Similarly, in the green sub-pixel (G), light emitted from the light-emitting device 203G is emitted through the green color filter 206G, and in the blue sub-pixel (B), light emitted from the light-emitting device 203B is emitted through the blue color filter 206B.

[0256] A black matrix 209 (which can also be called a black layer) may be provided at the end of one type of color filter. Furthermore, the color filters of each color and the black matrix 209 may be covered with an overcoat layer that transmits visible light.

[0257] 3C has a configuration in which one pixel has a red subpixel (R), a green subpixel (G), a blue subpixel (B), and a white subpixel (W). In Fig. 3C, light from the light-emitting device 203W of the white subpixel (W) is emitted to the outside of the light-emitting device without passing through a color filter.

[0258] The optical distance between first electrode 211 and second electrode 215 in light-emitting device 203W may be the same as or different from any of light-emitting devices 203R, 203G, and 203B.

[0259] For example, when the light emitted from light-emitting device 203W is white light with a low color temperature, and the intensity of light with a blue wavelength is to be increased, it is preferable to set the optical distance in light-emitting device 203W equal to optical distance 220B in light-emitting device 203B, as shown in Fig. 3C. This allows the light obtained from light-emitting device 203W to approach white light with a desired color temperature.

[0260] While Fig. 3A shows an example in which a common EL layer 213 is used for the light-emitting devices of the subpixels of each color, as shown in Fig. 4A, different EL layers may be used for the light-emitting devices of the subpixels of each color. The above-described microcavity structure can also be applied to Fig. 4A.

[0261] 4A shows an example in which light-emitting device 203R has EL layer 213R, light-emitting device 203G has EL layer 213G, and light-emitting device 203B has EL layer 213B. EL layers 213R, 213G, and 213B may have common layers. For example, EL layers 213R, 213G, and 213B may have different light-emitting layer configurations and other layers may be common layers. In FIG. 4A, light emitted by light-emitting devices 203R, 203G, and 203B may be extracted through a color filter or without a color filter.

[0262] Although a top-emission light-emitting device is shown in FIG. 3A, a light-emitting device having a structure in which light is extracted from the substrate 201 side on which the transistor 210 is formed (bottom-emission light-emitting device) as shown in FIG. 4B is also one embodiment of the present invention.

[0263] In a bottom-emission light-emitting device, it is preferable to provide color filters of each color between the substrate 201 and the light-emitting devices. 4B shows an example in which a transistor 210 is formed on the substrate 201, an insulating layer 202a is formed on the transistor 210, color filters 206R, 206G, and 206B are formed on the insulating layer 202a, an insulating layer 202b is formed on the color filters 206R, 206G, and 206B, and light-emitting devices 203R, 203G, and 203B are formed on the insulating layer 202b.

[0264] In the case of a top-emission light-emitting device, a light-shielding substrate and a light-transmitting substrate can be used as the substrate 201, and a light-transmitting substrate can be used as the substrate 205.

[0265] In the case of a bottom-emission light-emitting device, the substrate 205 can be a light-shielding substrate or a light-transmitting substrate, and the substrate 201 can be a light-transmitting substrate.

[0266] [Configuration example 3 of light-emitting device] The light-emitting device of one embodiment of the present invention can be a passive matrix type or an active matrix type. An active matrix type light-emitting device will be described with reference to FIG.

[0267] Fig. 5A shows a top view of the light emitting device, and Fig. 5B shows a cross-sectional view taken along the dashed dotted line AA' shown in Fig. 5A.

[0268] The active matrix light-emitting device shown in FIGS. 5A and 5B includes a pixel portion 302, a circuit portion 303, a circuit portion 304a, and a circuit portion 304b.

[0269] The circuit portion 303, the circuit portion 304a, and the circuit portion 304b can function as a scan line driver circuit (gate driver) or a signal line driver circuit (source driver), or may be a circuit that electrically connects an external gate driver or source driver to the pixel portion 302.

[0270] A lead wiring 307 is provided on the first substrate 301. The lead wiring 307 is electrically connected to an FPC 308, which is an external input terminal. The FPC 308 transmits external signals (e.g., video signals, clock signals, start signals, reset signals, etc.) and potentials to the circuit portion 303, the circuit portion 304a, and the circuit portion 304b. A printed wiring board (PWB) may be attached to the FPC 308. The configuration shown in FIGS. 5A and 5B can also be referred to as a light-emitting module having a light-emitting device (or light-emitting apparatus) and an FPC.

[0271] The pixel portion 302 has a plurality of pixels each having an organic EL device 317, a transistor 311, and a transistor 312. The transistor 312 is electrically connected to a first electrode 313 of the organic EL device 317. The transistor 311 functions as a switching transistor. The transistor 312 functions as a current control transistor. Note that the number of transistors included in each pixel is not particularly limited and can be appropriately provided as needed.

[0272] The circuit portion 303 has a plurality of transistors including a transistor 309, a transistor 310, etc. The circuit portion 303 may be formed of a circuit including transistors of the same conductivity type (either N-type or P-type), or may be formed of a CMOS circuit including N-type transistors and P-type transistors. The circuit portion 303 may also have a configuration including an external driver circuit.

[0273] The structure of the transistor included in the light-emitting device of this embodiment is not particularly limited. For example, a planar transistor, a staggered transistor, an inverted staggered transistor, or the like can be used. Furthermore, either a top-gate or bottom-gate transistor structure may be used. Alternatively, gates may be provided above and below a semiconductor layer in which a channel is formed.

[0274] The crystallinity of a semiconductor material used for a transistor is not particularly limited, and any of an amorphous semiconductor and a crystalline semiconductor (a microcrystalline semiconductor, a polycrystalline semiconductor, a single crystal semiconductor, or a semiconductor having a crystalline region in part) may be used. The use of a crystalline semiconductor is preferable because it can suppress deterioration of transistor characteristics.

[0275] The semiconductor layer of the transistor preferably contains a metal oxide (also referred to as an oxide semiconductor). Alternatively, the semiconductor layer of the transistor may contain silicon. Examples of silicon include amorphous silicon and crystalline silicon (such as low-temperature polysilicon and single-crystal silicon).

[0276] The semiconductor layer preferably contains, for example, indium, M (wherein M is one or more elements selected from gallium, aluminum, silicon, boron, yttrium, tin, copper, vanadium, beryllium, titanium, iron, nickel, germanium, zirconium, molybdenum, lanthanum, cerium, neodymium, hafnium, tantalum, tungsten, and magnesium), and zinc. In particular, M is preferably one or more elements selected from aluminum, gallium, yttrium, and tin.

[0277] In particular, it is preferable to use an oxide containing indium (In), gallium (Ga), and zinc (Zn) (also referred to as IGZO) as the semiconductor layer.

[0278] When the semiconductor layer is an In-M-Zn oxide, the sputtering target used to deposit the In-M-Zn oxide preferably has an atomic ratio of In equal to or greater than the atomic ratio of M. Examples of atomic ratios of metal elements in such sputtering targets include In:M:Zn=1:1:1, In:M:Zn=1:1:1.2, In:M:Zn=2:1:3, In:M:Zn=3:1:2, In:M:Zn=4:2:3, In:M:Zn=4:2:4.1, In:M:Zn=5:1:6, In:M:Zn=5:1:7, In:M:Zn=5:1:8, In:M:Zn=6:1:6, and In:M:Zn=5:2:5.

[0279] The transistors included in the circuit portion 303, the circuit portion 304a, and the circuit portion 304b may have the same structure or different structures from the transistors included in the pixel portion 302. The transistors included in the circuit portion 303, the circuit portion 304a, and the circuit portion 304b may all have the same structure or may have two or more types. Similarly, the transistors included in the pixel portion 302 may all have the same structure or may have two or more types.

[0280] The end of the first electrode 313 is covered with an insulating layer 314. The insulating layer 314 can be made of an organic compound such as a negative photosensitive resin or a positive photosensitive resin (acrylic resin), or an inorganic compound such as silicon oxide, silicon oxynitride, or silicon nitride. The upper or lower end of the insulating layer 314 preferably has a curved surface. This can improve the coverage of a film formed on the insulating layer 314.

[0281] An EL layer 315 is provided over the first electrode 313, and a second electrode 316 is provided over the EL layer 315. The EL layer 315 includes a light-emitting layer, a hole-injection layer, a hole-transport layer, an electron-transport layer, an electron-injection layer, a charge-generation layer, and the like. The EL layer 315 preferably includes the organic compound of one embodiment of the present invention described in Embodiment 1. For example, the organic compound is preferably included as one or both of a host material for the light-emitting layer and a material for the electron-transport layer.

[0282] The plurality of transistors and the plurality of organic EL devices 317 are sealed by the first substrate 301, the second substrate 306, and the sealant 305. A space 318 surrounded by the first substrate 301, the second substrate 306, and the sealant 305 may be filled with an inert gas (nitrogen, argon, etc.) or an organic substance (including the sealant 305).

[0283] Epoxy resin or glass frit can be used for the sealant 305. Note that it is preferable to use a material that is as moisture- and oxygen-impermeable as possible for the sealant 305. When glass frit is used as the sealant, it is preferable that the first substrate 301 and the second substrate 306 are glass substrates in terms of adhesiveness.

[0284] 5C and 5D show examples of transistors that can be used in the light-emitting device.

[0285] The transistor 320 shown in FIG. 5C includes a conductive layer 321 functioning as a gate, an insulating layer 328 functioning as a gate insulating layer, a semiconductor layer 327 having a channel formation region 327i and a pair of low-resistance regions 327n, a conductive layer 322a connected to one of the pair of low-resistance regions 327n, a conductive layer 322b connected to the other of the pair of low-resistance regions 327n, an insulating layer 325 functioning as a gate insulating layer, a conductive layer 323 functioning as a gate, and an insulating layer 324 covering the conductive layer 323. The insulating layer 328 is located between the conductive layer 321 and the channel formation region 327i. The insulating layer 325 is located between the conductive layer 323 and the channel formation region 327i. The transistor 320 is preferably covered with an insulating layer 326. The insulating layer 326 may be included as a component of the transistor 320.

[0286] The conductive layer 322a and the conductive layer 322b are each connected to the low-resistance region 327n through an opening provided in the insulating layer 324. One of the conductive layer 322a and the conductive layer 322b functions as a source, and the other functions as a drain.

[0287] The insulating layer 325 is provided to overlap at least the channel formation region 327i of the semiconductor layer. The insulating layer 325 may cover the top surface and side surfaces of the pair of low-resistance regions 327n.

[0288] 5D includes a conductive layer 331 functioning as a gate, an insulating layer 338 functioning as a gate insulating layer, conductive layers 332a and 332b functioning as a source and a drain, a semiconductor layer 337, an insulating layer 335 functioning as a gate insulating layer, and a conductive layer 333 functioning as a gate. The insulating layer 338 is located between the conductive layer 331 and the semiconductor layer 337. The insulating layer 335 is located between the conductive layer 333 and the semiconductor layer 337. The transistor 330 is preferably covered with an insulating layer 334. The insulating layer 334 may be included as a component of the transistor 330.

[0289] The transistor 320 and the transistor 330 have a structure in which a semiconductor layer in which a channel is formed is sandwiched between two gates. The two gates may be connected and the same signal may be supplied to drive the transistor. Alternatively, the threshold voltage of the transistor may be controlled by applying a potential for controlling the threshold voltage to one of the two gates and a potential for driving to the other.

[0290] It is preferable that at least one insulating layer covering the transistor is made of a material that is resistant to the diffusion of impurities such as water and hydrogen. This allows the insulating layer to function as a barrier layer. With this structure, it is possible to effectively prevent impurities from diffusing into the transistor from the outside, thereby improving the reliability of the light-emitting device.

[0291] An inorganic insulating film is preferably used for each of the insulating layer 325, the insulating layer 326, the insulating layer 328, the insulating layer 334, the insulating layer 335, and the insulating layer 338. Examples of the inorganic insulating film that can be used include a silicon nitride film, a silicon oxynitride film, a silicon oxide film, a silicon nitride oxide film, an aluminum oxide film, and an aluminum nitride film. Alternatively, a hafnium oxide film, an yttrium oxide film, a zirconium oxide film, a gallium oxide film, a tantalum oxide film, a magnesium oxide film, a lanthanum oxide film, a cerium oxide film, a neodymium oxide film, and the like may also be used. Two or more of the above insulating films may be stacked.

[0292] Materials that can be used for various conductive layers constituting a light-emitting device include metals such as aluminum, titanium, chromium, nickel, copper, yttrium, zirconium, molybdenum, silver, tantalum, and tungsten, or alloys containing these metals as the main component. Films containing these materials can be used as single layers or multilayer structures. Examples include a single-layer structure of an aluminum film containing silicon, a two-layer structure in which an aluminum film is stacked on a titanium film, a two-layer structure in which an aluminum film is stacked on a tungsten film, a two-layer structure in which a copper film is stacked on a copper-magnesium-aluminum alloy film, a two-layer structure in which a copper film is stacked on a titanium film, a two-layer structure in which a copper film is stacked on a tungsten film, a three-layer structure in which a titanium film or titanium nitride film is stacked on an aluminum film or copper film, and a three-layer structure in which a titanium film or titanium nitride film is further stacked on top of that, and a three-layer structure in which a molybdenum film or molybdenum nitride film is stacked on an aluminum film or copper film, and a molybdenum film or molybdenum nitride film is further stacked on top of that. Alternatively, oxides such as indium oxide, tin oxide, or zinc oxide may be used. Furthermore, copper containing manganese is preferably used because it improves the controllability of the shape by etching.

[0293] This embodiment mode can be combined with other embodiment modes as appropriate.

[0294] (Fourth embodiment) In this embodiment, electronic devices of one embodiment of the present invention will be described with reference to drawings.

[0295] Examples of electronic devices include television sets, computer monitors, digital cameras, digital video cameras, digital photo frames, mobile phones (also called mobile phones or mobile phone devices), portable game consoles, personal digital assistants, audio playback devices, large game machines such as pachinko machines, biometric authentication devices, and testing equipment.

[0296] The electronic device of one embodiment of the present invention has a light-emitting device of one embodiment of the present invention in a display portion, and therefore has high emission efficiency and high reliability.

[0297] The display unit of the electronic device of this embodiment can display images with resolutions of, for example, full high definition, 4K2K, 8K4K, 16K8K, or higher. The screen size of the display unit can be 20 inches or more diagonally, 30 inches or more diagonally, 50 inches or more diagonally, 60 inches or more diagonally, or 70 inches or more diagonally.

[0298] Since the electronic device according to one embodiment of the present invention is flexible, it can be incorporated along the curved surface of the inner or outer wall of a house or building, or the interior or exterior of an automobile.

[0299] Furthermore, the electronic device of one embodiment of the present invention may include a secondary battery, and it is preferable that the secondary battery can be charged using contactless power transmission.

[0300] Examples of secondary batteries include lithium ion secondary batteries such as lithium polymer batteries (lithium ion polymer batteries) that use a gel electrolyte, nickel-metal hydride batteries, nickel-cadmium batteries, organic radical batteries, lead-acid batteries, air secondary batteries, nickel-zinc batteries, and silver-zinc batteries.

[0301] The electronic device of one embodiment of the present invention may include an antenna. By receiving a signal through the antenna, images, information, or the like can be displayed on a display portion. When the electronic device includes an antenna and a secondary battery, the antenna may be used for contactless power transmission.

[0302] The electronic device of this embodiment may have a sensor (including a function to measure force, displacement, position, velocity, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared rays).

[0303] The electronic device of the present embodiment can have various functions, such as a function to display various information (still images, videos, text images, etc.) on a display unit, a touch panel function, a function to display a calendar, date, time, etc., a function to execute various software (programs), a wireless communication function, a function to read out programs or data recorded on a recording medium, etc.

[0304] 6A shows an example of a television device. A television device 7100 has a display unit 7000 built into a housing 7101. Here, the housing 7101 is supported by a stand 7103.

[0305] The light-emitting device of one embodiment of the present invention can be applied to the display portion 7000.

[0306] 6A can be operated using an operation switch provided on the housing 7101 or a separate remote control 7111. Alternatively, a touch sensor may be provided on the display unit 7000, and operation may be performed by touching the display unit 7000 with a finger or the like. The remote control 7111 may have a display unit that displays information output from the remote control 7111. Using the operation keys or touch panel provided on the remote control 7111, it is possible to operate the channel and volume, and to control the video displayed on the display unit 7000.

[0307] The television device 7100 is configured to include a receiver, a modem, and the like. The receiver can receive general television broadcasts. In addition, by connecting to a wired or wireless communication network via the modem, it is possible to perform one-way (from sender to receiver) or two-way (between sender and receiver, or between receivers, etc.) information communication.

[0308] 6B shows an example of a laptop personal computer 7200. The laptop personal computer 7200 includes a housing 7211, a keyboard 7212, a pointing device 7213, an external connection port 7214, and the like. A display portion 7000 is incorporated in the housing 7211.

[0309] The light-emitting device of one embodiment of the present invention can be applied to the display portion 7000.

[0310] 6C and 6D show an example of digital signage.

[0311] 6C includes a housing 7301, a display unit 7000, and a speaker 7303. The digital signage 7300 may further include an LED lamp, operation keys (including a power switch or an operation switch), a connection terminal, various sensors, a microphone, and the like.

[0312] 6D shows a digital signage 7400 attached to a cylindrical pole 7401. The digital signage 7400 has a display unit 7000 provided along the curved surface of the pole 7401.

[0313] 6C and 6D, the light-emitting device of one embodiment of the present invention can be applied to the display portion 7000.

[0314] The larger the display unit 7000, the more information can be provided at one time. Also, the larger the display unit 7000, the more easily it will attract people's attention, which can increase the advertising effectiveness of, for example, advertisements.

[0315] Applying a touch panel to the display unit 7000 is preferable because it not only displays images or videos on the display unit 7000 but also allows the user to intuitively operate it. Furthermore, when used to provide information such as route information or traffic information, intuitive operation can improve usability.

[0316] 6C and 6D, it is preferable that the digital signage 7300 or the digital signage 7400 can wirelessly link with an information terminal 7311 or an information terminal 7411, such as a smartphone carried by a user. For example, advertising information displayed on the display unit 7000 can be displayed on the screen of the information terminal 7311 or the information terminal 7411. Furthermore, the display on the display unit 7000 can be switched by operating the information terminal 7311 or the information terminal 7411.

[0317] Furthermore, it is also possible to cause the digital signage 7300 or the digital signage 7400 to execute a game using the screen of the information terminal 7311 or the information terminal 7411 as an operation means (controller), thereby allowing an unspecified number of users to simultaneously participate in and enjoy the game.

[0318] 7A to 7F show an example of a portable information terminal having a flexible display unit 7001. FIG.

[0319] The display portion 7001 is manufactured using the light-emitting device of one embodiment of the present invention. For example, a light-emitting device that can be bent with a curvature radius of 0.01 mm to 150 mm can be used. The display portion 7001 may be provided with a touch sensor, and a mobile information terminal can be operated by touching the display portion 7001 with a finger or the like.

[0320] 7A to 7C show an example of a foldable mobile information terminal. Fig. 7A shows mobile information terminal 7600 in an unfolded state, Fig. 7B shows a state in the process of changing from either the unfolded state or the folded state, and Fig. 7C shows mobile information terminal 7600 in a folded state. Mobile information terminal 7600 has excellent portability in the folded state, and has excellent viewability in the unfolded state due to its seamless, wide display area.

[0321] The display portion 7001 is supported by three housings 7601 connected by hinges 7602. By bending the two housings 7601 via the hinges 7602, the portable information terminal 7600 can be reversibly transformed from an unfolded state to a folded state.

[0322] 7D and 7E show an example of a foldable mobile information terminal. FIG. 7D shows a mobile information terminal 7650 folded so that the display portion 7001 faces inward, and FIG. 7E shows a mobile information terminal 7650 folded so that the display portion 7001 faces outward. The mobile information terminal 7650 has a display portion 7001 and a non-display portion 7651. When the mobile information terminal 7650 is not in use, folding the mobile information terminal 7650 so that the display portion 7001 faces inward can prevent the display portion 7001 from getting dirty or scratched.

[0323] 7F shows an example of a wristwatch-type portable information terminal. The portable information terminal 7800 includes a band 7801, a display portion 7001, an input / output terminal 7802, an operation button 7803, and the like. The band 7801 functions as a housing. The portable information terminal 7800 can be equipped with a flexible battery 7805. The battery 7805 may be disposed overlapping the display portion 7001 or the band 7801, for example.

[0324] The band 7801, the display portion 7001, and the battery 7805 are flexible, so that the portable information terminal 7800 can be easily bent into a desired shape.

[0325] The operation button 7803 can be provided with various functions, such as time setting, power on / off operation, wireless communication on / off operation, silent mode activation / deactivation, power saving mode activation / deactivation, etc. For example, the functions of the operation button 7803 can be freely set by an operating system incorporated in the mobile information terminal 7800.

[0326] Furthermore, by touching an icon 7804 displayed on the display unit 7001 with a finger or the like, an application can be started.

[0327] The mobile information terminal 7800 is also capable of performing standardized short-range wireless communication. For example, hands-free conversation is possible by communicating with a wirelessly enabled headset.

[0328] The portable information terminal 7800 may also have an input / output terminal 7802. When the portable information terminal 7800 has the input / output terminal 7802, data can be directly exchanged with another information terminal through a connector. Charging can also be performed through the input / output terminal 7802. Note that the charging operation of the portable information terminal exemplified in this embodiment may be performed by contactless power transmission without using an input / output terminal.

[0329] FIG. 8A shows the appearance of an automobile 9700. FIG. 8B shows a driver's seat of the automobile 9700. The automobile 9700 includes a body 9701, wheels 9702, a windshield 9703, a light 9704, a fog lamp 9705, and the like. The light-emitting device of one embodiment of the present invention can be used for a display portion of the automobile 9700. For example, the light-emitting device of one embodiment of the present invention can be provided in the display portions 9710 to 9715 shown in FIG. 8B. Alternatively, the light-emitting device of one embodiment of the present invention may be used for the light 9704 or the fog lamp 9705.

[0330] The display portion 9710 and the display portion 9711 are display devices provided on the windshield of an automobile. The light-emitting device of one embodiment of the present invention can have a so-called see-through state, in which the other side can be seen through, by forming electrodes and wirings using a light-transmitting conductive material. If the display portion 9710 or the display portion 9711 is see-through, the display portion 9710 or the display portion 9711 does not obstruct visibility even when driving the automobile 9700. Therefore, the light-emitting device of one embodiment of the present invention can be installed on the windshield of the automobile 9700. When a transistor or the like is provided to drive the light-emitting device, a light-transmitting transistor such as an organic transistor using an organic semiconductor material or a transistor using an oxide semiconductor is preferably used.

[0331] The display unit 9712 is a display device provided on a pillar. For example, by displaying an image from an imaging means provided on the vehicle body on the display unit 9712, the view blocked by the pillar can be complemented. The display unit 9713 is a display device provided on the dashboard. For example, by displaying an image from an imaging means provided on the vehicle body on the display unit 9713, the view blocked by the dashboard can be complemented. That is, by displaying an image from an imaging means provided on the outside of the vehicle, blind spots can be complemented and safety can be improved. Furthermore, by displaying an image that complements the invisible parts, safety can be confirmed more naturally and without discomfort.

[0332] FIG. 8C shows the interior of a vehicle equipped with bench seats for the driver's seat and passenger seat. Display unit 9721 is a display device provided in the door. For example, by displaying an image from an imaging means provided in the vehicle body on display unit 9721, it is possible to complement the view blocked by the door. Display unit 9722 is a display device provided in the steering wheel. Display unit 9723 is a display device provided in the center of the seat surface of the bench seat. Note that a display device can be installed on the seat surface or backrest, and the display device can be used as a seat heater using the heat generated by the display device as a heat source.

[0333] The display unit 9714, the display unit 9715, or the display unit 9722 can provide various information by displaying navigation information, a speedometer, a tachometer, mileage, a fuel gauge, gear status, air conditioning settings, and the like. The display items and layout displayed on the display units can be changed as appropriate to suit the user's preferences. The above information can also be displayed on the display units 9710 to 9713, the display unit 9721, and the display unit 9723. The display units 9710 to 9715 and the display units 9721 to 9723 can also be used as lighting devices. The display units 9710 to 9715 and the display units 9721 to 9723 can also be used as heating devices.

[0334] Furthermore, since the electronic device of one embodiment of the present invention includes the light-emitting device of one embodiment of the present invention as a light source, the electronic device has high emission efficiency and high reliability. For example, the light-emitting device of one embodiment of the present invention can be used as a light source that emits visible light or near-infrared light. The light-emitting device of one embodiment of the present invention can also be used as a light source for a lighting device.

[0335] FIG. 9A shows a biometric authentication device for finger veins, and includes a housing 911, a light source 912, a detection stage 913, and the like. By placing a finger on the detection stage 913, the shape of the veins can be imaged. A light source 912 that emits near-infrared light is provided above the detection stage 913, and an imaging device 914 is provided below it. The detection stage 913 is made of a material that transmits near-infrared light, and the near-infrared light that is irradiated from the light source 912 and passes through the finger can be imaged by the imaging device 914. An optical system may be provided between the detection stage 913 and the imaging device 914. The above device configuration can also be used in a biometric authentication device for palm veins.

[0336] The light-emitting device of one embodiment of the present invention can be used for the light source 912. The light-emitting device of one embodiment of the present invention can be installed in a curved shape and can uniformly irradiate an object with light. In particular, a light-emitting device that emits near-infrared light having the strongest peak intensity in a wavelength range of 700 nm to 1200 nm can be preferably used. The position of veins can be detected by receiving light that has passed through a finger or a palm and imaging it. This function can be used for biometric authentication. Furthermore, by combining the light-emitting device with a global shutter system, highly accurate sensing is possible even when the object is moving.

[0337] 9B, the light source 912 may have a plurality of light-emitting units, such as light-emitting units 915, 916, and 917. Each of the light-emitting units 915, 916, and 917 may emit light of a different wavelength, and may emit light at a different timing. Therefore, by changing the wavelength and angle of the emitted light, different images can be captured consecutively, and multiple images can be used for authentication, thereby achieving high security.

[0338] FIG. 9C shows a biometric authentication device for palm veins, which includes a housing 921, an operation button 922, a detection unit 923, a light source 924 that emits near-infrared light, and the like. The shape of palm veins can be recognized by holding a hand over the detection unit 923. A personal identification number or the like can also be input using the operation button. A light source 924 is disposed around the detection unit 923 and irradiates a target object (hand). Reflected light from the target object is incident on the detection unit 923. A light-emitting device according to one embodiment of the present invention can be used for the light source 924. An imaging device 925 is disposed directly below the detection unit 923 and can capture an image of the target object (the entire image of the hand). Note that an optical system may be provided between the detection unit 923 and the imaging device 925. The above-described device configuration can also be used for a biometric authentication device for finger veins.

[0339] FIG. 9D shows a nondestructive inspection device, which includes a housing 931, an operation panel 932, a conveying mechanism 933, a monitor 934, a detection unit 935, and a light source 938 that emits near-infrared light. The light-emitting device of one embodiment of the present invention can be used for the light source 938. An inspected member 936 is conveyed by the conveying mechanism 933 to a position directly below the detection unit 935. The inspected member 936 is irradiated with near-infrared light from the light source 938, and the transmitted light is captured by an imaging device 937 provided in the detection unit 935. The captured image is displayed on a monitor 934. The inspected member is then conveyed to the exit of the housing 931, where defective members are sorted and collected. By capturing images using near-infrared light, defective elements such as defects and foreign matter inside the inspected member can be detected nondestructively and quickly.

[0340] FIG. 9E illustrates a mobile phone including a housing 981, a display portion 982, operation buttons 983, an external connection port 984, a speaker 985, a microphone 986, a first camera 987, a second camera 988, and the like. The mobile phone includes a touch sensor in the display portion 982. The housing 981 and the display portion 982 are flexible. Any operation, such as making a call or inputting text, can be performed by touching the display portion 982 with a finger or a stylus. The first camera 987 can acquire a visible light image, and the second camera 988 can acquire an infrared light image (near-infrared light image). The mobile phone or the display portion 982 illustrated in FIG. 9E may include a light-emitting device of one embodiment of the present invention.

[0341] This embodiment mode can be combined with other embodiment modes as appropriate. [Example]

[0342] (Synthesis Example 1) Example 1 This example describes a synthesis method for an organic compound according to one embodiment of the present invention. This example describes a synthesis method for 10-[(3'-dibenzothiophen-4-yl)biphenyl-3-yl]naphtho[1',2':4,5]furo[2,3-b]quinoxaline (abbreviation: 10mDBtBPNfqn) represented by structural formula (100) in Embodiment 1.

[0343] [ka]

[0344] Step 1: Synthesis of 7-chloro-3-(2-methoxynaphthalen-1-yl)quinoxalin-2-amine First, 2.49 g of 3,7-dichloroquinoxaline-2-amine, 2.38 g of 2-methoxynaphthalene-1-boronic acid, 3.90 g of cesium carbonate, 46 mL of 1,4-dioxane, and 23 mL of water were placed in a three-necked flask equipped with a reflux condenser, and the inside of the flask was replaced with nitrogen. After degassing by stirring under reduced pressure, 1.38 g of tetrakis(triphenylphosphine)palladium(0) (abbreviated as Pd(PPh3)4) was added and the mixture was stirred at 80°C for 6 hours to allow the reaction to proceed.

[0345] The reaction solution was extracted with dichloromethane to obtain a residue. The residue was then purified by silica gel column chromatography using dichloromethane:ethyl acetate = 50:1 as a developing solvent to obtain the desired quinoxaline derivative (yellow solid, yield 2.89 g, 70%). The synthesis scheme for step 1 is shown in (a-1).

[0346] [ka]

[0347] Step 2: Synthesis of 10-chloronaphtho[1',2':4,5]furo[2,3-b]quinoxaline Next, 2.89 g of 7-chloro-3-(2-methoxynaphthalen-1-yl)quinoxalin-2-amine obtained in Step 1, 90 mL of dehydrated tetrahydrofuran, and 90 mL of glacial acetic acid were placed in a three-neck flask and the inside atmosphere was replaced with nitrogen. After the flask was cooled to -10°C, 3.0 mL of tert-butyl nitrite was added dropwise, and the mixture was stirred at -10°C for 1 hour and at 0°C for 18 hours. After the specified time had elapsed, 400 mL of water was added to the resulting suspension, and the mixture was suction filtered to obtain the desired quinoxaline derivative (yellow-white solid, 1.63 g, 64% yield). The synthetic scheme for Step 2 is shown in (a-2).

[0348] [ka]

[0349] <Step 3: Synthesis of 10mDBtBPNfqn> Furthermore, 1.63 g of 10-chloronaphtho[1',2':4,5]furo[2,3-b]quinoxaline obtained in Step 2, 3.29 g of 3'-(4-dibenzothiophene)-1,1'-biphenyl-3-boronic acid, 5.48 g of tripotassium phosphate, 1.42 g of tert-butyl alcohol, and 60 mL of diethylene glycol dimethyl ether (abbreviated as diglyme) were placed in a three-necked flask and the inside of the flask was purged with nitrogen. After degassing by stirring under reduced pressure, 0.10 g of palladium(II) acetate (abbreviated as Pd(OAc)2) and 0.32 g of di(1-adamantyl)-n-butylphosphine (abbreviated as CataCXium A) were added and the mixture was stirred at 140 °C for 31.5 hours to react.

[0350] After a predetermined time had elapsed, the resulting suspension was filtered under suction and washed with water and ethanol. The resulting solid was dissolved in toluene and filtered through a filter aid consisting of layers of celite, alumina, and celite in that order. The target product was then recrystallized from toluene to give a yellow solid (yellow solid, 2.19 g, yield 69%).

[0351] The resulting yellow solid (2.19 g) was purified by train sublimation. The conditions for the sublimation purification were to heat the solid to 340 °C under a pressure of 2.7 Pa and an argon gas flow rate of 15 mL / min. After sublimation purification, the target yellow solid was obtained in an amount of 1.48 g and a yield of 68%. The synthesis scheme for Step 3 is shown in (a-3).

[0352] [ka]

[0353] Nuclear magnetic resonance spectroscopy of the yellow solid obtained in step 3 ( 1 The results of the analysis by H-NMR are shown below. 1 The H-NMR chart is shown in Figure 10. From this result, it was found that 10mDBtBPNfqn represented by structural formula (100) was obtained in this example.

[0354] 1 H-NMR.δ(CDCl3):7.47-7.50(m,2H),7.60-7.62(m,2H),7.67(t,3H),7.78-7.80(m,3H),7.8 5-7.90(m,4H),8.07(d,1H),8.13(d,2H),8.19-8.23(m,4H),8.49-8.51(m,2H),9.39(d,1H).

[0355] Next, the ultraviolet-visible absorption spectrum (hereinafter simply referred to as the "absorption spectrum") and emission spectrum of 10mDBtBPNfqn in toluene solution are shown in Figure 11A. The horizontal axis represents wavelength, and the vertical axis represents absorption intensity and emission intensity. Both the absorption spectrum and emission spectrum were measured at room temperature.

[0356] Absorption spectra were measured using a UV-visible spectrophotometer (V550, manufactured by JASCO Corporation). The absorption spectrum of 10mDBtBPNfqn in toluene solution was calculated by subtracting the absorption spectrum obtained by measuring toluene in a quartz cell from the absorption spectrum obtained by measuring the toluene solution in a quartz cell. Furthermore, a fluorometer (FS920, manufactured by Hamamatsu Photonics Co., Ltd.) was used to measure the emission spectrum. The emission spectrum of 10mDBtBPNfqn in toluene solution was measured by placing the toluene solution in a quartz cell.

[0357] As shown in FIG. 11A, in the toluene solution of 10mDBtBPNfqn, absorption peaks were observed near 387 nm and 406 nm, and emission wavelength peaks were observed near 422 nm and 443 nm (excitation wavelength: 292 nm).

[0358] Next, the absorption and emission spectra of the solid thin film of 10mDBtBPNfqn were measured. The solid thin film was prepared on a quartz substrate by vacuum deposition. The absorption spectrum of the thin film was calculated from the absorbance (-log 10 It was calculated from [%T / (100-%R)], where %T represents transmittance and %R represents reflectance. An ultraviolet-visible spectrophotometer (U-4100, Hitachi High-Technologies Corporation) was used to measure the absorption spectrum. A fluorometer (FS920, Hamamatsu Photonics K.K.) was used to measure the emission spectrum. Both the absorption spectrum and the emission spectrum were measured at room temperature. The measurement results of the absorption spectrum and the emission spectrum of the obtained solid thin film are shown in Figure 11B. The horizontal axis represents wavelength, and the vertical axis represents absorption intensity and emission intensity.

[0359] From the results in FIG. 11B, the solid thin film of 10mDBtBPNfqn exhibited absorption peaks around 397 nm and 418 nm, and an emission wavelength peak around 514 nm (excitation wavelength: 400 nm).

[0360] It has been found that the organic compound 10mDBtBPNfqn according to one embodiment of the present invention is a suitable host material for phosphorescent materials that emit light at red or longer wavelengths. 10mDBtBPNfqn can also be used as a host material or an emissive material used together with a visible light-emitting material (such as a fluorescent material, delayed fluorescent material, or phosphorescent material).

[0361] Differential scanning calorimetry (DSC) was also performed on 10mDBtBPNfqn. A differential scanning calorimeter (Pyris 1, manufactured by PerkinElmer Japan Co., Ltd.) was used for the measurements. One cycle of measurement consisted of heating from -10°C to 350°C at a rate of 40°C / min, holding at 350°C for 3 minutes, and then cooling from 350°C to -10°C at a rate of 100°C / min. Three cycles of measurement were performed in this example. The glass transition temperature (Tg) was found to be 126°C based on the results of the third heating cycle. Therefore, the 10mDBtBPNfqn synthesized in this example was found to be a highly heat-resistant material.

[0362] Since 10mDBtBPNfqn has a Tg of 126°C, it can improve the heat resistance of light-emitting devices.

[0363] 10mDBtBPNfqn is Ar in general formula (G0) 1 is an unsubstituted naphthalene ring. 1 The naphthalene ring allows the T1 level to be lowered and the LUMO level to be deepened, which is thought to have enabled the synthesis of a host material suitable for materials that emit light at energy levels in the red and longer wavelengths.

[0364] 10mDBtBPNfqn is an example of an organic compound according to one embodiment of the present invention that has a dibenzothiophene skeleton as a hole-transport skeleton or a fused ring. It is believed that the inclusion of the dibenzothiophene ring enabled the synthesis of an organic compound with high chemical stability and high heat resistance. [Example]

[0365] Example 1 This example describes the results of fabricating a light-emitting device according to one embodiment of the present invention. Specifically, the structure, fabrication method, and characteristics of light-emitting device 1, which uses 10-[(3'-dibenzothiophen-4-yl)biphenyl-3-yl]naphtho[1',2':4,5]furo[2,3-b]quinoxaline (abbreviation: 10mDBtBPNfqn) (structural formula (100)) described in Example 1 as a light-emitting layer, are described.

[0366] 12 shows the structure of the light-emitting device 1 used in this example, and its specific configuration is shown in Table 1. The chemical formulas of the materials used in this example are shown below.

[0367] [Table 1]

[0368] [ka]

[0369] <<Fabrication of Light-Emitting Device 1>> The light-emitting device 1 shown in this example has a structure in which, as shown in FIG. 12 , a first electrode 801 is formed on a substrate 800, a hole injection layer 811, a hole transport layer 812, a light-emitting layer 813, an electron transport layer 814, and an electron injection layer 815 are sequentially stacked on the first electrode 801, and a second electrode 803 is stacked on the electron injection layer 815.

[0370] First, a first electrode 801 was formed on a substrate 800. The electrode area was 4 mm 2 The dimensions of the substrate 800 were 2 mm x 2 mm. A glass substrate was used as the substrate 800. The first electrode 801 was formed by depositing indium tin oxide containing silicon oxide (ITSO) by sputtering to a thickness of 70 nm. In this example, the first electrode 801 functions as an anode.

[0371] Here, as a pretreatment, the surface of the substrate was washed with water, baked at 200°C for 1 hour, and then subjected to UV ozone treatment for 370 seconds.-4 The substrate was introduced into a vacuum deposition apparatus whose internal pressure had been reduced to about Pa, and after vacuum baking 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.

[0372] Next, a hole injection layer 811 was formed on the first electrode 801. The hole injection layer 811 was formed by evaporating the solution in a vacuum deposition apparatus for 10 minutes. -4 After reducing the pressure to 10 Pa, 1,3,5-tri(dibenzothiophen-4-yl)benzene (abbreviation: DBT3P-II) and molybdenum oxide were co-evaporated in a mass ratio of DBT3P-II:molybdenum oxide = 2:1 to form a film with a thickness of 80 nm.

[0373] Next, a hole transport layer 812 was formed on the hole injection layer 811. The hole transport layer 812 was formed by vapor deposition using N-(1,1'-biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9-dimethyl-9H-fluoren-2-amine (abbreviation: PCBBiF) to a thickness of 20 nm.

[0374] Next, the light-emitting layer 813 was formed over the hole-transport layer 812. 10mDBtBPNfqn, which is an organic compound of one embodiment of the present invention, was used as a host material, PCBBiF was used as an assist material, and (acetylacetonato)bis(2,3-diphenylquinoxalinato-N,C2′)iridium(III) (abbreviation: [Ir(dpq)2(acac)]) was used as a guest material (phosphorescent material) by co-evaporation in a weight ratio of 10mDBtBPNfqn:PCBBiF:[Ir(dpq)2(acac)]=0.8:0.2:0.1. The film thickness was 40 nm.

[0375] Next, an electron transport layer 814 was formed on the light-emitting layer 813. The electron transport layer 814 was formed by sequentially depositing 10mDBtBPNfqn to a thickness of 30 nm and 2,9-bis(naphthalen-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBphen) to a thickness of 15 nm.

[0376] Next, electron injection layer 815 was formed on electron transport layer 814. Electron injection layer 815 was formed by vapor deposition using lithium fluoride (LiF) so as to have a film thickness of 1 nm.

[0377] Next, a second electrode 803 was formed on the electron injection layer 815. The second electrode 803 was formed by vapor deposition of aluminum so as to have a film thickness of 200 nm. In this example, the second electrode 803 functions as a cathode.

[0378] Through the above steps, a light-emitting device including an EL layer sandwiched between a pair of electrodes was formed on the substrate 800. Note that the hole injection layer 811, the hole transport layer 812, the light-emitting layer 813, the electron transport layer 814, and the electron injection layer 815 described in the above steps are functional layers that constitute the EL layer in one embodiment of the present invention. Furthermore, in all of the evaporation steps in the above-described manufacturing method, evaporation was performed using a resistance heating method.

[0379] The light-emitting device fabricated as described above is sealed with another substrate (not shown). When sealing using another substrate (not shown), another substrate (not shown) coated with an adhesive that hardens when exposed to ultraviolet light is fixed on the substrate 800 in a glove box with a nitrogen atmosphere, and the substrates are bonded together so that the adhesive adheres to the periphery of the light-emitting device formed on the substrate 800. During sealing, 365 nm ultraviolet light is applied at 6 J / cm. 2 The adhesive was solidified by irradiation and then stabilized by heat treatment at 80°C for 1 hour.

[0380] <Operating characteristics of light-emitting device 1> The operating characteristics of the light-emitting device 1 were measured. The measurements were carried out at room temperature (in an atmosphere maintained at 25° C.).

[0381] FIG. 13 shows the current density-luminance characteristics of the light-emitting device 1. FIG. 14 shows the voltage-luminance characteristics of the light-emitting device 1. FIG. 15 shows the luminance-current efficiency characteristics of the light-emitting device 1. FIG. 16 shows the voltage-current characteristics of the light-emitting device 1. FIG. 17 shows the luminance-external quantum efficiency characteristics of the light-emitting device 1.

[0382] Table 2 shows 600cd / m 2 1 shows the main initial characteristic values of the light-emitting device 1 in the vicinity of the luminance.

[0383] [Table 2]

[0384] As shown in FIGS. 13 to 17 and Table 2, it was found that the light-emitting device 1 had high luminous efficiency.

[0385] In addition, 2.5 mA / cm2 was applied to light-emitting device 1. 2 The emission spectrum obtained when a current was passed through the light-emitting device 1 at a current density of 100 s is shown in Fig. 18. As shown in Fig. 18, the light-emitting device 1 exhibited an emission spectrum with a maximum peak at around 680 nm, which was attributable to the emission of [Ir(dpq)2(acac)] contained in the light-emitting layer 813.

[0386] Next, a reliability test was conducted on the light-emitting device 1. The results of the reliability test are shown in Fig. 19. In Fig. 19, the vertical axis represents normalized luminance (%) when the initial luminance is set to 100%, and the horizontal axis represents driving time (h). The reliability test was conducted at a current density of 75 mA / cm 2 The light-emitting device 1 was driven by setting the

[0387] The results of the reliability test showed that the light-emitting device 1 exhibited high reliability. This can be attributed to the effect of using 10mDBtBPNfqn (Structural Formula (100)), an organic compound according to one embodiment of the present invention, in the light-emitting layer of the light-emitting device 1.

[0388] The combination of 10mDBtBPNfqn and PCBBiF used in the light-emitting layer of Light-Emitting Device 1 forms an exciplex. When the organic compound of one embodiment of the present invention has a dibenzothiophene skeleton as a hole-transport skeleton, the HOMO level is thought to be deepened, the hole-transport property is reduced, or an exciplex is more likely to be formed, which suggests that the reliability of the light-emitting device can be improved. [Example]

[0389] Example 1 In this example, fabrication results of light-emitting devices according to one embodiment of the present invention are described. Specifically, light-emitting device 2 and light-emitting device 3 were fabricated using 10-[(3'-dibenzothiophen-4-yl)biphenyl-3-yl]naphtho[1',2':4,5]furo[2,3-b]quinoxaline (abbreviation: 10mDBtBPNfqn) (Structural Formula (100)) described in Example 1 as a light-emitting layer, and the results of measuring the characteristics are described.

[0390] The specific configurations of light-emitting devices 2 and 3 used in this example are shown in Table 3. The structures of light-emitting devices 2 and 3 are the same as those of light-emitting device 1 (FIG. 12), and the fabrication method can be referred to in Example 2. The chemical formulas of the materials used in this example are shown below.

[0391] [Table 3]

[0392] [ka]

[0393] <Operation characteristics of light-emitting device 2 and light-emitting device 3> The operating characteristics of the light-emitting devices 2 and 3 were measured. The measurements were carried out at room temperature (in an atmosphere maintained at 25°C).

[0394] FIG. 20 shows the current density-luminance characteristics of light-emitting devices 2 and 3. FIG. 21 shows the voltage-luminance characteristics of light-emitting devices 2 and 3. FIG. 22 shows the luminance-current efficiency characteristics of light-emitting devices 2 and 3. FIG. 23 shows the voltage-current characteristics of light-emitting devices 2 and 3. FIG. 24 shows the luminance-external quantum efficiency characteristics of light-emitting devices 2 and 3.

[0395] Table 4 shows 1000cd / m 2 1 shows the main initial characteristic values of the light-emitting devices 2 and 3 in the vicinity.

[0396] [Table 4]

[0397] As shown in FIGS. 20 to 24 and Table 4, it was found that light-emitting devices 2 and 3 had high luminous efficiency.

[0398] In addition, 2.5 mA / cm2 is supplied to light-emitting devices 2 and 3. 2 25 shows the emission spectra obtained when a current was passed through the light-emitting device 813 at a current density of 100 kHz. Light-emitting devices 2 and 3 exhibit emission spectra with a maximum peak near 650 nm, which is attributable to the emission of bis{4,6-dimethyl-2-[5-(5-cyano-2-methylphenyl)-3-(3,5-dimethylphenyl)-2-pyrazinyl-κN]phenyl-κC}(2,2,6,6-tetramethyl-3,5-heptanedionato-κO,O')iridium(III) (abbreviation: [Ir(dmdppr-mCP)(dpm)]) contained in the light-emitting layer 813. Specifically, light-emitting device 2 exhibits a maximum peak near 650 nm, and light-emitting device 3 exhibits a maximum peak near 649 nm.

[0399] Next, reliability tests were conducted on light-emitting devices 2 and 3. The results of the reliability tests are shown in Figure 26. In Figure 26, the vertical axis represents normalized luminance (%) when the initial luminance is taken as 100%, and the horizontal axis represents the device operating time (h). The reliability tests were conducted at a current density of 75 mA / cm 2 and light-emitting devices 2 and 3 were driven.

[0400] The results of the reliability test showed that the light-emitting devices 2 and 3 exhibited high reliability.

[0401] In this example, N-(4-biphenyl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-9-phenyl-9H-carbazol-3-amine (abbreviation: PCBiF) was used for the light-emitting layer 813 in light-emitting device 2, and N-(1,1′-biphenyl-4-yl)-N-[4-(dibenzofuran-4-yl)phenyl]-9,9-dimethyl-9H-fluoren-2-amine (abbreviation: FrBBiF-II) was used for the light-emitting layer 813 in light-emitting device 3. The HOMO level of PCBiF is −5.26 eV, and the HOMO level of FrBBiF-II is −5.42 eV. It was found that when 10mDBtBPNfqn, an organic compound of one embodiment of the present invention, was used for the light-emitting layer 813, a light-emitting device with favorable characteristics could be fabricated regardless of the combination of the two. This indicates that the range of suitable values for the HOMO levels of materials (assist materials) that can be used in combination with 10mDBtBPNfqn is wide, and there is a wide range of options for assist materials. [Example]

[0402] In this example, the substitution position (R 1 or R 2 The results of calculations to determine whether differences occur in the LUMO level and T1 level depending on the substitution position of the fluorine atom are explained below.

[0403] In this example, calculations were performed on organic compounds represented by structural formulas (C1) to (C4).

[0404] [ka]

[0405] The quantum chemical calculation program Gaussian09 was used for molecular orbital calculations. The basis set was 6-311G, and the functional was B3LYP to optimize the structures of each molecule in the singlet ground state (S0) and the lowest triplet excited state (T1).

[0406] Table 5 shows the calculated values of the LUMO level and T1 level (wavelength).

[0407] [Table 5]

[0408] As shown in Table 5, the organic compounds represented by structural formulas (C1) to (C4) all have deep LUMO levels and T1 levels (wavelengths) around 600 nm. In particular, structural formula (C2) has the deepest LUMO level and the lowest T1 level (longest wavelength).

[0409] The results of this example suggest that the organic compound of one embodiment of the present invention is suitable for a light-emitting device (particularly, a light-emitting device that emits red or near-infrared light) because it has a deep LUMO level and a low T level. [Example]

[0410] (Synthesis Example 2) Example 1 This example describes a synthesis method for an organic compound according to one embodiment of the present invention. This example describes a synthesis method for 12-[(3'-dibenzothiophen-4-yl)biphenyl-3-yl]phenanthro[9',10':4,5]furo[2,3-b]quinoxaline (abbreviation: 12mDBtBPPnfqn) represented by structural formula (113) in Embodiment 1.

[0411] [ka]

[0412] Step 1: Synthesis of 7-chloro-3-(10-methoxyphenanthrene-9-yl)quinoxalin-2-amine First, 2.70 g of 3,7-dichloroquinoxaline-2-amine, 3.27 g of 10-methoxyphenanthrene-9-boronic acid, 4.22 g of cesium carbonate, 50 mL of 1,4-dioxane, and 25 mL of water were placed in a three-necked flask equipped with a reflux condenser, and the inside of the flask was replaced with nitrogen. After degassing by stirring under reduced pressure, 0.75 g of tetrakis(triphenylphosphine)palladium(0) (abbreviation: Pd(PPh3)4) was added and the mixture was stirred at 80°C for 11 hours to allow the reaction to proceed.

[0413] After a predetermined time, the precipitated solid was filtered off under suction and washed with water and ethanol. It was then purified by silica gel column chromatography using dichloromethane as a developing solvent to obtain the desired quinoxaline derivative (yellow solid, yield 3.30 g, 68%). The synthesis scheme for step 1 is shown in (b-1).

[0414] [ka]

[0415] Step 2: Synthesis of 12-chlorophenanthro[9',10':4,5]furo[2,3-b]quinoxaline Next, 3.29 g of 7-chloro-3-(10-methoxyphenanthren-9-yl)quinoxalin-2-amine obtained in Step 1, 100 mL of dehydrated tetrahydrofuran, and 100 mL of glacial acetic acid were placed in a three-neck flask and the inside of the flask was purged with nitrogen. After cooling the flask to -10 °C, 3.1 mL of tert-butyl nitrite was added dropwise and the mixture was stirred at -10 °C for 1 hour and at 0 °C for 24 hours. After the specified time had elapsed, 400 mL of water was added to the resulting suspension, and the mixture was suction filtered to obtain the desired quinoxaline derivative (yellow solid, 2.52 g, 82% yield). The synthetic scheme for Step 2 is shown in (b-2).

[0416] [ka]

[0417] <Step 3: Synthesis of 12mDBtBPPnfqn> In addition, 1.19 g of 12-chlorophenanthro[9',10':4,5]furo[2,3-b]quinoxaline (obtained in Step 2), 1.58 g of 3'-(4-dibenzothiophene)-1,1'-biphenyl-3-boronic acid, 2.19 g of tripotassium phosphate, 0.76 g of tert-butyl alcohol, and 27 mL of diethylene glycol dimethyl ether (diglyme) were placed in a three-neck flask and purged with nitrogen. After degassing the contents of the flask by stirring under reduced pressure, 15 mg of palladium(II) acetate (Pd(OAc)2) and 48 mg of di(1-adamantyl)-n-butylphosphine (CataCXium A) were added and the mixture was stirred at 150 °C for 15 hours.

[0418] After a predetermined time had elapsed, the resulting suspension was filtered under suction and washed with water and ethanol. The resulting solid was dissolved in toluene and filtered through a filter aid consisting of layers of celite, alumina, and celite in that order. The target product was then recrystallized from toluene to obtain a yellow solid (yellow solid, yield 1.25 g, 56%).

[0419] The resulting yellow solid (1.24 g) was purified by train sublimation. The conditions for the sublimation purification were a pressure of 2.6 Pa, argon gas flow at a flow rate of 10 mL / min, and heating the solid at 380 °C. After sublimation purification, the target yellow solid was obtained in an amount of 0.85 g and a yield of 69%. The synthesis scheme for Step 3 is shown in (b-3).

[0420] [ka]

[0421] Nuclear magnetic resonance spectroscopy of the yellow solid obtained in step 3 ( 1 The results of the analysis by H-NMR are shown below. 1 The H-NMR chart is shown in Figure 27. From this result, it was found that 12mDBtBPPnfqn represented by structural formula (113) was obtained in this example.

[0422] 1H-NMR.δ(CDCl3):7.47-7.50(m,2H),7.60-7.69(m,4H),7.78-7.94(m,9H),8.12(s,1H),8.15(s ,1H),8.19-8.23(m,3H),8.50-8.52(m,2H),8.65(d,1H),8.81(d,1H),8.85(d,1H),9.49(s,1H). [Explanation of symbols]

[0423] 101: first electrode, 102: second electrode, 103: EL layer, 103a: EL layer, 103b: EL layer, 103c: EL layer, 104: charge generation layer, 111: hole injection layer, 112: hole transport layer, 113: light emitting layer, 114: electron transport layer, 115: electron injection layer, 201: substrate, 202: insulating layer, 202a: insulating layer, 202b: insulating layer, 203B: light emitting device, 203G: light emitting device, 203R: light emitting device, 203W: light emitting device, 204: insulating layer, 205: substrate, 206B: color filter, 206G: color filter, 206R: color filter, 2 07: space, 208: adhesive layer, 209: black matrix, 210: transistor, 211: first electrode, 212G: conductive layer, 212R: conductive layer, 213: EL layer, 213B: EL layer, 213G: EL layer, 213R: EL layer, 215: second electrode, 220B: optical distance, 220G: optical distance, 220R: optical distance, 301: first substrate, 302: pixel section, 303: circuit section, 304a: circuit section, 304b: circuit section, 305: sealing material, 306: second substrate, 307: wiring, 308: FPC, 309: transistor, 310: transistor, 311: transistor transistor, 312, 313, first electrode, 314, insulating layer, 315, EL layer, 316, second electrode, 317, organic EL device, 318, space, 320, transistor, 321, conductive layer, 322a, conductive layer, 322b, conductive layer, 323, conductive layer, 324, insulating layer, 325, insulating layer, 326, insulating layer, 327, semiconductor layer, 327i, channel formation region, 327n, low resistance region, 328, insulating layer, 330, transistor, 331, conductive layer, 332a, conductive layer, 332b, conductive layer, 333, conductive layer, 334, insulating layer, 335, insulating layer, 337, semiconductor layer, 338: insulating layer, 401: first electrode, 402: EL layer, 403: second electrode, 405: insulating layer, 406: conductive layer, 407: adhesive layer, 416: conductive layer, 420: substrate, 422: adhesive layer, 423: barrier layer, 424: insulating layer, 450: organic EL device, 490a: substrate, 490b: substrate, 490c: barrier layer, 800: substrate, 801: first electrode, 803: second electrode, 811: hole injection layer, 812: hole transport layer, 813: light emitting layer, 814: electron transport layer, 815: electron injection layer, 911: housing, 912: light source, 913: detection stage, 914: imaging device,915: light emitting unit, 916: light emitting unit, 917: light emitting unit, 921: housing, 922: operation button, 923: detection unit, 924: light source, 925: imaging device, 931: housing, 932: operation panel, 933: conveyance mechanism, 934: monitor, 935: detection unit, 936: inspected member, 937: imaging device, 938: light source, 981: housing, 982: display unit, 983: operation button, 984: external connection port, 985: speaker, 986: microphone, 987: first camera, 988: second camera, 7000: display unit, 7001: display unit, 7100: television device, 7101: housing, 7103: stand, 7111: remote control device, 7200: notebook personal computer, 7211: housing, 7212: keyboard, 7213: pointing device, 7214: external connection port, 7300: digital signage, 7301: housing, 7303: speaker, 7311: information terminal, 7400: digital signage, 7401: pillar, 7411: information terminal, 7600: mobile information terminal, 7601: housing, 7602: hinge, 7650: mobile information terminal, 7651: non-display part, 7800: mobile information terminal, 7801: band, 7802: input / output terminal, 78 03: Operation button, 7804: Icon, 7805: Battery, 9700: Car, 9701: Body, 9702: Wheel, 9703: Windshield, 9704: Light, 9705: Fog lamp, 9710: Display, 9711: Display, 9712: Display, 9713: Display, 9714: Display, 9715: Display, 9721: Display, 9722: Display, 9723: Display,

Claims

1. A compound represented by the following formula (a4): 【Chemical 1】 (wherein Q represents oxygen or sulfur, Ar １ represents a substituted or unsubstituted fused aromatic ring; Y １ represents a halogen, and Y １ is one or two.)

2. In claim 1, Ar １ represents any one of a substituted or unsubstituted naphthalene ring, a substituted or unsubstituted phenanthrene ring, and a substituted or unsubstituted chrysene ring.

3. A compound represented by the following formula (1001) or formula (1002): 【Chemistry 2】

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