Organic compounds, light-emitting devices

Abstract

To provide an organic compound having a low refractive index. 【solutions】To provide an organic compound represented by the general formula (G1). In the formula, Q 1 to Q 3 represents N or CH and at least two of them are N, R 1 to R 3 represents an alkyl group having 1 to 6 carbon atoms or a phenyl group, n represents an integer of 2 or more and 5 or less, R 10 represents hydrogen, an alkyl group having 1 to 6 carbon atoms, etc., R 11 to R 24 represents hydrogen, an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, etc., and at least one of them is a heteroaryl group having 3 to 30 carbon atoms. JPEG2026115004000061.jpg77167

Description

[Technical Field]

[0001] One aspect of the present invention relates to organic compounds, organic semiconductor devices, light-emitting devices, light-receiving devices, light-emitting apparatuses, light-receiving apparatuses, display devices, electronic equipment, lighting apparatuses, and electronic devices. However, one aspect of the present invention is not limited to the above-mentioned technical field. The technical field of one aspect of the invention disclosed herein relates to a product, a method, or a method of manufacture. Alternatively, one aspect of the present invention relates to a process, a machine, a manufacture, or a composition of matter. More specifically, examples of the technical field of one aspect of the present invention disclosed herein include semiconductor devices, display devices, liquid crystal display devices, light-emitting devices, lighting apparatuses, energy storage devices, memory devices, imaging devices, methods for driving them, or methods for manufacturing them. [Background technology]

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

[0003] Because these light-emitting devices are self-emissive, using them as pixels in a display offers advantages over liquid crystal displays, such as higher visibility and the elimination of the need for a backlight, making them suitable elements for flat panel displays. Another major advantage is that displays using such light-emitting devices can be manufactured to be thin and lightweight. Furthermore, they are characterized by their extremely fast response speed. In addition, since these light-emitting devices can form a continuous two-dimensional light-emitting layer, they can produce light in a planar manner. This is a feature that is difficult to obtain with point light sources such as incandescent bulbs and LEDs, or line light sources such as fluorescent lamps, making them highly valuable as planar light sources that can be applied to lighting and other applications.

[0004] While displays and lighting devices using light-emitting devices can be applied to various electronic devices, research and development are underway to find light-emitting devices with even better characteristics.

[0005] One of the problems often raised when discussing organic light-emitting diodes (OLEDs) is their low light extraction efficiency. In particular, attenuation due to reflection caused by differences in refractive index between adjacent layers is a major factor in reducing the efficiency of the device. To mitigate this effect, a configuration has been proposed in which a layer made of a low refractive index material is formed inside the EL layer (see, for example, Non-Patent Document 1). Light-emitting devices with this configuration can achieve higher light extraction efficiency, and consequently higher external quantum efficiency, than light-emitting devices with conventional configurations.

[0006] Furthermore, the EL layer of an organic EL element can be formed by various methods, including vacuum deposition, gravure printing, offset printing, screen printing, inkjet printing, or spin coating. In recent years, it has been discovered that giant surface potentials (GSPs) can occur in films obtained by vacuum deposition. GSP is a phenomenon caused by spontaneous orientation polarization (SOP), which results from the orientation of the permanent electric dipole moment of a deposited organic compound film being biased in the direction of film thickness.

[0007] The surface potential of a vapor-deposited film exhibiting GSP changes at a constant rate without saturating as the film thickness increases. For example, a vapor-deposited film of tris(8-quinolinolato)aluminum(III) (abbreviated as Alq3) has a surface potential of approximately 28V at a film thickness of 560nm. This electric field strength is 5 × 10⁻¹⁰ 5 It reaches V / cm, which is about the same magnitude as the electric field strength during operation of a typical light-emitting device.

[0008] The GSP slope (GSP_slope) is expressed as ΔV / Δd when the change in surface potential is ΔV (mV) for a film in which the GSP changes proportionally to the film thickness, and the change in surface potential is ΔV (mV) for a change in film thickness Δd (nm). Note that a positive GSP_slope occurs when the surface potential increases with increasing film thickness, and a negative GSP_slope occurs when the surface potential decreases with increasing film thickness. Alq3, as described above, can be described as a material with a positive GSP_slope in its film. Furthermore, layers with a positive GSP_slope have a low potential on the substrate side, while layers with a negative GSP_slope have a high potential on the substrate side.

[0009] As mentioned above, this GSP is a phenomenon caused by SOP resulting from the bias in the orientation of the permanent electric dipole moment in the film thickness direction. In other words, in layers where GSP_slope is positive, it can be considered that a negative polarization charge is induced on the deposition start side (substrate side) and a positive polarization charge is induced on the deposition end side (second electrode side). Similarly, in layers where GSP_slope is negative, it can be considered that a positive polarization charge is induced on the deposition start side (substrate side) and a negative polarization charge is induced on the deposition end side (second electrode side). The induction of such polarization charges is the origin of GSP.

[0010] Since vapor-deposited films of organic compounds often have a positive GSP_slope, for example, when a second layer is deposited in contact with a first layer, the signs of the GSP_slope of the first and second layers will be the same positive. In this case, the polarization charge on the first layer side of the second layer cancels out with the polarization charge on the second layer side of the first layer, and only the remaining charge can be considered as the interfacial charge (fixed charge) at the interface between the first and second layers.

[0011] Interfacial charges at the interfaces between such deposited films can adversely affect the characteristics of organic EL devices. Therefore, research and development are underway to control the GSP of deposited films of organic compounds. For example, Non-Patent Literature 2 discloses that the GSP_slope of a deposited film changes significantly depending on the substituent introduced into the organic compound. [Prior art documents] [Non-patent literature]

[0012] [Non-Patent Document 1] Jaeho Lee, et al., "Synergetic electrode architecture for efficient graphene-based flexible organic light-emitting diodes," Nature Communications, June 2, 2016, DOI: 10.1038 / ncomms11791 [Non-Patent Document 2] Masaki Tanaka and 3 others, “Spontaneous formation of metastable orientation with well-organized permanent dipole moment in organic glassy films”, Nature Materials, 2022, Vol.21, p.819-825 [Non-Patent Document 3] Yutaka Noguchi and 7 others, “Charge accumulation at organic semiconductor interfaces due to a permanent dipole moment and its orientational order in bilayer devices”, Journal of Applied Physics, 2012, 111, 114508 [Non-Patent Document 4] Hiroshi Noguchi, et al., "Orientational Polarization Phenomena of Polar Molecules and Interface Properties of Organic Thin Film Devices," Journal of the Vacuum Society of Japan, 2015, Vol. 58, No. 3. [Overview of the project] [Problems that the invention aims to solve]

[0013] Using organic compounds with high carrier transport properties, low refractive index, and low GSP_slope in the carrier transport layer of organic EL devices is useful for improving the characteristics of organic EL devices. However, developing such organic compounds is not easy.

[0014] This is because there is a trade-off between a low refractive index and high carrier transport or reliability when used in light-emitting devices. This problem stems from the fact that carrier transport and reliability in organic compounds largely depend on the presence of unsaturated bonds, and organic compounds with many unsaturated bonds tend to have high refractive indices. Increasing the number of saturated hydrocarbon groups in an organic compound to lower the refractive index tends to reduce carrier transport and reliability.

[0015] Furthermore, because saturated hydrocarbon groups are not conjugated, the dispersion forces between molecules are smaller compared to unsaturated hydrocarbon groups, resulting in smaller van der Waals forces. As a result, when forming a vacuum-deposited film using compounds containing both saturated and unsaturated hydrocarbon groups, the molecules tend to orient themselves such that the unsaturated hydrocarbon group portion faces the substrate or the already deposited film side, while the saturated hydrocarbon group portion faces the film surface side. In addition, since saturated hydrocarbon groups are electron-donating groups, the molecular dipole moment tends to be positive on the saturated hydrocarbon group side. Thus, based on the relationship between the orientation resulting from vacuum deposition and the molecular permanent electric dipole moment, films formed with compounds containing saturated hydrocarbon groups tend to exhibit a large positive GSP_slope.

[0016] Therefore, one aspect of the present invention aims to provide an organic compound with a low refractive index in a film. Alternatively, one aspect of the present invention aims to provide an organic compound with a small GSP_slope in a film. Alternatively, one aspect of the present invention aims to provide an organic compound having carrier transport properties. Alternatively, one aspect of the present invention aims to provide an organic compound that has high carrier transport properties in a film, a low refractive index, and a low GSP_slope. Alternatively, one aspect of the present invention aims to provide a novel organic compound.

[0017] Alternatively, one aspect of the present invention aims to provide a light-emitting device with high luminous efficiency. Alternatively, one aspect of the present invention aims to provide a light-emitting device with a low driving voltage. Alternatively, one aspect of the present invention aims to provide a light-emitting device, light-emitting apparatus, electronic device, display device, and electronic device, respectively, with low power consumption.

[0018] Furthermore, the description of these problems does not preclude the existence of other problems. Moreover, one aspect of the present invention does not need to solve all of these problems. Other problems will naturally become apparent from the description in the specification, drawings, and claims, and it is possible to extract other problems from the description in the specification, drawings, and claims. [Means for solving the problem]

[0019] One aspect of the present invention is an organic compound represented by the general formula (G1).

[0020]

Chemical formula

[0021] In the general formula (G1), Q 1 to Q 3 each independently represents N or CH (including CD), and at least two of Q 1 to Q 3 are N, R 1 to R 3 each independently represents an alkyl group having 1 to 6 carbon atoms or a phenyl group, n represents an integer of 2 or more and 5 or less, R 10 represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 3 to 10 carbon atoms, R 11 to R 24 each independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, and at least one of R 11 to R 24 is a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms. A plurality of R 1 may be the same or different. A plurality of R 2 may be the same or different. A plurality of R 3 may be the same or different. When 5 - n is 2 or more, a plurality of R 10 may be the same or different.

[0022] Also, one aspect of the present invention is an organic compound represented by the general formula (G2).

[0023]

Chemical formula

[0024] In the general formula (G2), Q 1 ~Q 3 Each independently represents N or CH (including CD), and Q 1 ~Q 3 At least two of them are N, and R 1 ~R 3 Each independently represents an alkyl group or phenyl group having 1 to 6 carbon atoms, n represents an integer between 2 and 5, and R 10 R represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms. 12 ~R 24 Each of the following independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, while Hy represents a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms. 1 They may be the same or different. Multiple R 2 They may be the same or different. Multiple R 3 They may be the same or different. If 5-n is 2 or greater, there may be multiple R 10 They may be the same or different.

[0025] In the organic compounds of each of the above configurations, the substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms is more preferably nitrogen-containing.

[0026] In the organic compounds of each of the above configurations, it is more preferable that one or more atoms constituting the aromatic ring of the substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms are nitrogen atoms.

[0027] In the organic compounds of each of the above configurations, the substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms is more preferably a substituted or unsubstituted pyridinyl group, a substituted or unsubstituted pyrimidinyl group, or a substituted or unsubstituted pyrazinyl group.

[0028] In the organic compounds of each of the above configurations, it is more preferable that the substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms has at least one of an alkyl group having 1 to 6 carbon atoms and a cycloalkyl group having 3 to 10 carbon atoms.

[0029] Furthermore, one aspect of the present invention is an organic compound represented by the general formula (G3).

[0030] [ka]

[0031] In the general formula (G3), Q 1 ~Q 3 Each independently represents N or CH (including CD), and Q 1 ~Q 3 At least two of them are N, and R 1 ~R 3 Each independently represents an alkyl group or phenyl group having 1 to 6 carbon atoms, n represents an integer between 2 and 5, and R 10 R represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms. 12 ~R 24 Each independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, R 25 ~R 28 Each of these independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms. 1 They may be the same or different. Multiple R 2 They may be the same or different. Multiple R 3 They may be the same or different. If 5-n is 2 or greater, there may be multiple R 10 They may be the same or different.

[0032] Furthermore, one aspect of the present invention is an organic compound represented by general formula (G4).

[0033] [ka]

[0034] In the general formula (G4), Q 1 ~Q 3 Each independently represents N or CH (including CD), and Q 1 ~Q 3 At least two of them are N, and R 1 ~R 3 Each independently represents an alkyl group or phenyl group having 1 to 6 carbon atoms, n represents an integer between 2 and 5, and R 10 R represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms. 12 ~R 24 Each independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, R 25 ~R 28 Each of these independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms. 1 They may be the same or different. Multiple R 2 They may be the same or different. Multiple R 3 They may be the same or different. If 5-n is 2 or greater, there may be multiple R 10 They may be the same or different.

[0035] In the organic compounds of each of the above configurations, n is more preferably 2 or 3, and even more preferably 2.

[0036] Furthermore, one aspect of the present invention is an organic compound represented by the general formula (G5).

[0037] [ka]

[0038] In the general formula (G5), Q 1 ~Q 3 Each independently represents N or CH (including CD), and Q 1 ~Q 3 At least two of them are N, and R 1 ~R 6 Each independently represents an alkyl group or phenyl group having 1 to 6 carbon atoms, R 8 ~R 10 Each of these independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms, R 12 ~R 24 Each independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, R 25 ~R 28 Each of these independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms.

[0039] In the organic compounds of each of the above configurations, R 25 ~R 28 It is more preferable that at least one of these is an alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 3 to 10 carbon atoms.

[0040] In the organic compounds of each of the above configurations, Q 1 ~Q 3 However, it is more preferable if all values ​​are N.

[0041] Furthermore, one aspect of the present invention is an organic compound represented by structural formula (100).

[0042] [ka]

[0043] Furthermore, one aspect of the present invention is a light-emitting device having the organic compounds described above.

[0044] Furthermore, one aspect of the present invention is a light-emitting device comprising a first electrode, a second electrode, and an EL layer located between the first electrode and the second electrode, wherein the EL layer comprises a light-emitting layer and an electron transport layer, the electron transport layer is located between the light-emitting layer and the second electrode, the distance between the electron transport layer and the second electrode is 5 nm or less, and the electron transport layer has an organic compound comprising the above-described components.

[0045] Furthermore, one aspect of the present invention is a light-emitting device comprising a first electrode, a second electrode, and an EL layer located between the first electrode and the second electrode, wherein the EL layer comprises a light-emitting layer and an electron transport layer, the electron transport layer is located between the light-emitting layer and the second electrode, and the electron transport layer is a mixed layer comprising a first organic compound and a metal complex, the first organic compound comprising a π-electron-deficient heteroaromatic ring and a trialkylsilyl group having 3 to 18 carbon atoms.

[0046] In the organic compound having the above configuration, the π-electron-deficient heteroaromatic ring is more preferably a pyrimidine ring or a triazine ring.

[0047] Furthermore, one aspect of the present invention is a light-emitting device comprising a first electrode, a second electrode, and an EL layer located between the first electrode and the second electrode, wherein the EL layer comprises a light-emitting layer and an electron transport layer, the electron transport layer is located between the light-emitting layer and the second electrode, and the electron transport layer is a mixed layer comprising a first organic compound and a metal complex, the first organic compound being an organic compound represented by general formula (G0).

[0048] [ka]

[0049] In the general formula (G0), Q 1 ~Q 3 Each independently represents N or CH, and Q 1 ~Q 3 At least two of them are N, and R 1 ~R 3Each independently represents an alkyl group or phenyl group having 1 to 6 carbon atoms, n represents an integer between 1 and 5, and R 10 ~R 24 Each of these independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a trisubstituted silyl group having 3 to 18 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms. When n is 2 or more, multiple R 1 They may be the same or different. Multiple R 2 They may be the same or different. Multiple R 3 They may be the same or different. If 5-n is 2 or greater, there may be multiple R 10 They may be the same or different.

[0050] In the organic compounds of each of the above configurations, it is more preferable that the distance between the electron transport layer and the second electrode is 5 nm or less.

[0051] In the organic compounds of each of the above configurations, it is more preferable that the metal complex contains an alkali metal. [Effects of the Invention]

[0052] According to one aspect of the present invention, an organic compound with a low refractive index of the film can be provided. Alternatively, according to one aspect of the present invention, an organic compound with a small GSP_Slope of the film can be provided. Alternatively, according to one aspect of the present invention, an organic compound having carrier transport properties can be provided. Alternatively, according to one aspect of the present invention, an organic compound having high carrier transport properties, a low refractive index, and a low GSP_slope in the film can be provided. Alternatively, according to one aspect of the present invention, a novel organic compound can be provided.

[0053] Alternatively, according to one aspect of the present invention, a light-emitting device with high luminous efficiency can be provided. Alternatively, according to one aspect of the present invention, a light-emitting device with a low driving voltage can be provided. Alternatively, according to one aspect of the present invention, a light-emitting device, a light-emitting apparatus, an electronic device, a display device, and an electronic device with low power consumption can be provided.

[0054] Furthermore, the description of these effects does not preclude the existence of other effects. One aspect of the present invention does not necessarily have to possess all of these effects. Other effects can be extracted from the description, drawings, and claims. [Brief explanation of the drawing]

[0055] [Figure 1] Figures 1(A) to 1(F) illustrate the configuration of a light-emitting device according to an embodiment. [Figure 2] Figures 2(A) and 2(B) are perspective views showing examples of the display module configuration. [Figure 3] Figures 3(A) and 3(B) are cross-sectional views showing examples of the configuration of a display device. [Figure 4] Figure 4 is a perspective view showing an example of a display device configuration. [Figure 5] Figure 5 is a cross-sectional view showing an example of the configuration of a display device. [Figure 6] Figure 6 is a cross-sectional view showing an example of the configuration of a display device. [Figure 7] Figures 7(A) and 7(B) show examples of electronic devices. [Figure 8] Figures 8(A) through 8(F) show examples of electronic devices. [Figure 9] Figures 9(A) through 9(G) show examples of electronic devices. [Figure 10] Figure 10 is a diagram illustrating the configuration of the measuring device 1. [Figure 11] Figure 11 is a diagram illustrating the configuration of a light-emitting device according to an embodiment. [Figure 12]Figure 12 is a diagram illustrating the configuration of a light-emitting device according to an embodiment. [Figure 13] Figure 13 is the 1H-NMR chart of 2-[3-(2,6-dimethylpyridine-3-yl)-5-(4,6-diphenyl-1,3,5-triazine)]phenyl-4,4,5,5-tetramethyl-1,3,2-dioxaborolane. [Figure 14] Figure 14 is an enlarged view of the 1H-NMR chart of 2-[3-(2,6-dimethylpyridine-3-yl)-5-(4,6-diphenyl-1,3,5-triazine)]phenyl-4,4,5,5-tetramethyl-1,3,2-dioxaborolane. [Figure 15] Figure 15 shows the 1H-NMR chart of mmTMSPh-mDMePyPTzn. [Figure 16] Figure 16 is a magnified view of the 1H-NMR chart of mmTMSPh-mDMePyPTzn. [Figure 17] Figure 17 shows the emission and absorption spectra of a dichloromethane solution of mmTMSPh-mDMePyPTzn. [Figure 18] Figure 18 shows the emission and absorption spectra of a thin film of mmTMSPh-mDMePyPTzn. [Figure 19] Figure 19 shows the measured refractive index data for mmTMSPh-mDMePyPTzn. [Figure 20] Figures 20(A) through 20(C) show the stable structures of mmTMSPh-mDMePyPTzn used in the calculations. [Figure 21] Figures 21(A) through 21(C) show the stable structures of mmtBuPh-mDMePyPTzn used in the calculations. [Figure 22] Figure 22 shows the capacitance-voltage characteristics of the measuring device 1. [Figure 23] Figure 23 shows the current density-voltage characteristics of the measuring device 1. [Figure 24] Figure 24 shows the luminance-current density characteristics of light-emitting device G-1, reference light-emitting device G-2, and reference light-emitting device G-3. [Figure 25] Figure 25 shows the luminance-voltage characteristics of light-emitting device G-1, reference light-emitting device G-2, and reference light-emitting device G-3. [Figure 26] Figure 26 shows the current efficiency-luminance characteristics of light-emitting device G-1, reference light-emitting device G-2, and reference light-emitting device G-3. [Figure 27] Figure 27 shows the current density-voltage characteristics of light-emitting device G-1 and comparative light-emitting device G-2. [Figure 28] Figure 28 shows the external quantum efficiency-luminance characteristics of light-emitting device G-1, comparative light-emitting device G-2, and comparative light-emitting device G-3. [Figure 29] Figure 29 shows the field emission spectra of light-emitting device G-1, reference light-emitting device G-2, and reference light-emitting device G-3. [Figure 30] Figure 30 shows the capacitance-voltage characteristics of light-emitting device G-1 and comparative light-emitting device G-2. [Figure 31] Figure 31 shows the change in brightness of light-emitting device G-1, comparative light-emitting device G-2, and comparative light-emitting device G-3 with respect to operating time. [Figure 32] Figure 32 shows the luminance-current density characteristics of light-emitting device G-4 and comparative light-emitting device G-5. [Figure 33] Figure 33 shows the luminance-voltage characteristics of light-emitting device G-4 and comparative light-emitting device G-5. [Figure 34] Figure 34 shows the current efficiency-luminance characteristics of light-emitting device G-4 and comparative light-emitting device G-5. [Figure 35] Figure 35 shows the current density-voltage characteristics of light-emitting device G-4 and comparative light-emitting device G-5. [Figure 36] Figure 36 shows the external quantum efficiency-luminance characteristics of light-emitting device G-4 and comparative light-emitting device G-5. [Figure 37] Figure 37 shows the field emission spectra of light-emitting device G-4 and comparative light-emitting device G-5. [Figure 38]Figure 38 shows the luminance-current density characteristics of light-emitting device B-1 and comparative light-emitting device B-2. [Figure 39] Figure 39 shows the luminance-voltage characteristics of light-emitting device B-1 and comparative light-emitting device B-2. [Figure 40] Figure 40 shows the current efficiency-luminance characteristics of light-emitting device B-1 and comparative light-emitting device B-2. [Figure 41] Figure 41 shows the current density-voltage characteristics of light-emitting device B-1 and comparative light-emitting device B-2. [Figure 42] Figure 42 shows the external quantum efficiency-luminance characteristics of light-emitting device B-1 and comparative light-emitting device B-2. [Figure 43] Figure 43 shows the blue index-luminance characteristics of light-emitting device B-1 and comparative light-emitting device B-2. [Figure 44] Figure 44 shows the electroluminescence spectra of light-emitting device B-1 and comparative light-emitting device B-2. [Figure 45] Figure 45 shows the change in brightness of light-emitting device B-1 and comparative light-emitting device B-2 with respect to operating time. [Figure 46] Figure 46 shows the luminance-current density characteristics of light-emitting device B-3 and comparative light-emitting devices B-4 to B-6. [Figure 47] Figure 47 shows the luminance-voltage characteristics of light-emitting device B-3 and comparative light-emitting devices B-4 to B-6. [Figure 48] Figure 48 shows the current efficiency-luminance characteristics of light-emitting device B-3 and comparative light-emitting devices B-4 to B-6. [Figure 49] Figure 49 shows the current density-voltage characteristics of light-emitting device B-3 and comparative light-emitting devices B-4 through B-6. [Figure 50] Figure 50 shows the external quantum efficiency-luminance characteristics of light-emitting device B-3 and comparative light-emitting devices B-4 to B-6. [Figure 51]Figure 51 shows the blue index-luminance characteristics of light-emitting device B-3 and comparative light-emitting devices B-4 to B-6. [Figure 52] Figure 52 shows the electroluminescence spectra of light-emitting device B-3 and comparative light-emitting devices B-4 to B-6. [Figure 53] Figure 53 is the 1H-NMR chart of mmTMSPh-mPmPTzn. [Figure 54] Figure 54 is a magnified view of the 1H-NMR chart of mmTMSPh-mPmPTzn. [Figure 55] Figure 55 shows the emission and absorption spectra of a dichloromethane solution of mmTMSPh-mPmPTzn. [Figure 56] Figure 56 shows the emission and absorption spectra of the mmTMSPh-mPmPTzn thin film. [Figure 57] Figure 57 shows the measured refractive index data for mmTMSPh-mPmPTzn. [Figure 58] Figure 58 shows the luminance-current density characteristics of light-emitting device G-6, reference light-emitting device G-7, and reference light-emitting device G-8. [Figure 59] Figure 59 shows the luminance-voltage characteristics of light-emitting device G-6, reference light-emitting device G-7, and reference light-emitting device G-8. [Figure 60] Figure 60 shows the current efficiency-luminance characteristics of light-emitting device G-6, reference light-emitting device G-7, and reference light-emitting device G-8. [Figure 61] Figure 61 shows the current density-voltage characteristics of light-emitting device G-6, reference light-emitting device G-7, and reference light-emitting device G-8. [Figure 62] Figure 62 shows the external quantum efficiency-luminance characteristics of light-emitting device G-6, comparative light-emitting device G-7, and comparative light-emitting device G-8. [Figure 63] Figure 63 shows the field emission spectra of light-emitting device G-6, reference light-emitting device G-7, and reference light-emitting device G-8. [Figure 64]Figure 64 shows the change in brightness of light-emitting device G-6, comparative light-emitting device G-7, and comparative light-emitting device G-8 with respect to operating time. [Modes for carrying out the invention]

[0056] The embodiments of the present invention will be described in detail below with reference to the drawings. However, the present invention is not limited to the following description, and its form and details can be modified in various ways without departing from the spirit and scope of the present invention. Accordingly, the present invention shall not be interpreted as being limited to the contents of the embodiments shown below.

[0057] Please note that the positions, sizes, and ranges of each component shown in the drawings may not represent their actual positions, sizes, and ranges for the sake of ease of understanding. Therefore, the disclosed invention is not necessarily limited to the positions, sizes, and ranges disclosed in the drawings.

[0058] Furthermore, the ordinal numbers used in this specification, such as "first," "second," etc., are for convenience only and may not indicate the order of processes or stacking. Therefore, for example, "first" can be replaced with "second" or "third," etc., as appropriate in the explanation. Also, the ordinal numbers described in this specification may not be the same as the ordinal numbers used to specify an aspect of the present invention.

[0059] Furthermore, in this specification and other documents, when describing the structure of the invention using drawings, reference numerals that refer to the same thing may be used in common across different drawings.

[0060] Furthermore, in this specification, the terms "film" and "layer" are interchangeable. For example, the term "conductive layer" may be changed to "conductive film." Or, for example, the term "insulating film" may be changed to "insulating layer."

[0061] In this specification, etc., hydrogen (H) is referred to as light hydrogen ( 1H) and deuterium ( 2 Contains H or D). Light hydrogen is the stable isotope of hydrogen with a mass number of 1. Deuterium is the stable isotope of hydrogen with a mass number of 2.

[0062] (Embodiment 1) This embodiment describes an organic compound according to one aspect of the present invention.

[0063] One aspect of the present invention is an organic compound having a trisubstituted silyl group. In this specification, a trisubstituted silyl group refers to a monovalent group having a structure in which three substituents are bonded to a silicon atom (Si). Specific examples of the three substituents include alkyl groups and aryl groups. Alkyl groups are more preferable than aryl groups because they can lower the refractive index of the organic compound.

[0064] The inventors of this study analyzed the permanent electric dipole moments of the stable singlet ground state structures of trimethylsilylbenzene and tert-butylbenzene in order to investigate the effects of introducing a trisubstituted silyl group into an organic compound. Here, trimethylsilylbenzene was analyzed as an example of an organic compound having a trisubstituted silyl group, and tert-butylbenzene was analyzed as a comparative example. Furthermore, since both the trimethylsilyl group and the tert-butyl group contain saturated hydrocarbon groups, they are substituents that are expected to lower the refractive index of the organic compound when introduced into an aromatic ring.

[0065] [ka]

[0066] The calculation method used was Density Functional Theory (DFT). The functional used was B3LYP, and the basis function was 6-311G(d,p). Gaussian16 was used as the calculation program.

[0067] The calculations showed that the permanent electric dipole moment of tert-butylbenzene was 0.3110 Debye. This permanent electric dipole moment is the result of the electron-donating tert-butyl group donating electrons to the benzene ring. On the other hand, the permanent electric dipole moment of trimethylsilylbenzene was 0.0345 Debye, which is smaller than that of tert-butylbenzene and is close to zero. From these results, it was found that the trimethylsilyl group shows almost no electron-donating ability to the benzene ring. Therefore, it can be said that a trisubstituted silyl group has the effect of reducing the permanent electric dipole moment of a molecule because it is less electron-donating than a group having the same three substituents bonded to a carbon atom as the three substituents of the trisubstituted silyl group.

[0068] This effect allows molecules for organic semiconductors containing trisubstituted silyl groups to maintain a small permanent electric dipole moment. As a result, films formed by vacuum deposition using such molecules yield films with a small SOP (State of Operation).

[0069] Therefore, as one aspect of the present invention, the inventors have developed an organic compound in which a trisubstituted silyl group is introduced into the electron-transporting skeleton. The electron-transporting skeleton has a pyrimidine ring or triazine ring, which is a π-electron-deficient heteroaromatic ring, and three phenyl groups bonded to the ring. Furthermore, one of the three phenyl groups has a substituent having a trisubstituted silyl group. This organic compound is an organic compound that has electron-transporting properties, a low refractive index of the deposited film, and a small GSP_Slope. Moreover, by using this organic compound in the electron transport layer of a light-emitting device, the luminescence efficiency of the light-emitting device can be increased.

[0070] Next, an organic compound according to one aspect of the present invention will be described in more detail using a general formula. One aspect of the present invention is an organic compound represented by the general formula (G1).

[0071] [ka]

[0072] In general formula (G1), Q 1 to Q 3 each independently represents N or CH (including CD), and at least two of Q 1 to Q 3 are N, R 1 to R 3 each independently represents an alkyl group having 1 to 6 carbon atoms or a phenyl group, n represents an integer of 2 or more and 5 or less, and R 10 represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms, and R 11 to R 24 each independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, and at least one of R 11 to R 24 is a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms. A plurality of R 1 may be the same or different. A plurality of R 2 may be the same or different. A plurality of R 3 may be the same or different. When 5 - n is 2 or more, a plurality of R 10 may be the same or different.

[0073] Note that CH means carbon (C) bonded to hydrogen (H), and CD means carbon (C) bonded to deuterium (D).

[0074] By having a structure in which a substituent having a trisubstituted silyl group is bonded only to any one of the three phenyl groups bonded to the pyrimidine ring or the triazine ring, as in the organic compound represented by the general formula (G1), compared with the case where the substituent is bonded to two or more of the three phenyl groups bonded to the pyrimidine ring or the triazine ring, an increase in steric hindrance around the pyrimidine ring or the triazine ring can be suppressed, and the electron transporting property of the organic compound can be enhanced.

[0075] Furthermore, by adopting a structure in which at least one of the three phenyl groups bonded to a pyrimidine ring or triazine ring is substituted or unsubstituted with a heteroaryl group having 3 to 30 carbon atoms, as in the organic compound represented by general formula (G1), the electron transport properties of the organic compound can be further enhanced.

[0076] Furthermore, when the organic compound represented by general formula (G1) has a molecular weight of 1500 or less, more preferably 1000 or less, it is preferable that the deposition occurs below the thermal decomposition temperature of the organic compound when the film is formed by vacuum deposition.

[0077] Furthermore, one aspect of the present invention is an organic compound represented by the general formula (G2).

[0078] [ka]

[0079] In the general formula (G2), Q 1 ~Q 3 Each independently represents N or CH (including CD), and Q 1 ~Q 3 At least two of them are N, and R 1 ~R 3 Each independently represents an alkyl group or phenyl group having 1 to 6 carbon atoms, n represents an integer between 2 and 5, and R 10 R represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms. 12 ~R 24 Each of the following independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, while Hy represents a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms. 1 They may be the same or different. Multiple R 2 They may be the same or different. Multiple R 3They may be the same or different. If 5-n is 2 or greater, there may be multiple R 10 They may be the same or different.

[0080] General formula (G2) differs from general formula (G1) in that one of the three phenyl groups bonded to the pyrimidine or triazine ring is bonded to both a substituent with a trisubstituted silyl group and a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms. This configuration enhances the electron transport properties of the organic compound membrane and reduces the GSP_slope compared to cases where each of these groups is bonded to a different phenyl group.

[0081] In the organic compounds represented by the above general formulas, the substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms is preferably a nitrogen-containing group, more preferably a group in which one or more atoms constituting the aromatic ring are nitrogen atoms, and even more preferably a substituted or unsubstituted pyridinyl group, a substituted or unsubstituted pyrimidinyl group, or a substituted or unsubstituted pyrazinyl group. These substituents have high electron transport properties, and therefore can further enhance the electron transport properties of the organic compound. Furthermore, these substituents are preferred because no absorption is observed in the visible range, thus enabling the creation of highly efficient light-emitting devices.

[0082] Furthermore, in the organic compounds represented by the above general formulas, it is more preferable that the substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms has at least one of an alkyl group having 1 to 6 carbon atoms and a cycloalkyl group having 3 to 10 carbon atoms. This makes it possible to further lower the refractive index of the film made of the organic compound and to reduce the GSP_slope.

[0083] Furthermore, one aspect of the present invention is an organic compound represented by the general formula (G3).

[0084] [ka]

[0085] In the general formula (G3), Q 1 ~Q 3 Each independently represents N or CH (including CD), and Q 1 ~Q 3 At least two of them are N, and R 1 ~R 3 Each independently represents an alkyl group or phenyl group having 1 to 6 carbon atoms, n represents an integer between 2 and 5, and R 10 R represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms. 12 ~R 24 Each independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, R 25 ~R 28 Each of these independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms. 1 They may be the same or different. Multiple R 2 They may be the same or different. Multiple R 3 They may be the same or different. If 5-n is 2 or greater, there may be multiple R 10 They may be the same or different.

[0086] General formula (G3) differs from general formula (G2) in that Hy is limited to a substituted or unsubstituted pyridinyl group. This allows for improved electron transport properties of organic compounds while maintaining a low refractive index.

[0087] Furthermore, one aspect of the present invention is an organic compound represented by general formula (G4).

[0088] [ka]

[0089] In the general formula (G4), Q 1 ~Q3 Each independently represents N or CH (including CD), and Q 1 ~Q 3 At least two of them are N, and R 1 ~R 3 Each independently represents an alkyl group or phenyl group having 1 to 6 carbon atoms, n represents an integer between 2 and 5, and R 10 R represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms. 12 ~R 24 Each independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, R 25 ~R 28 Each of these independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms. 1 They may be the same or different. Multiple R 2 They may be the same or different. Multiple R 3 They may be the same or different. If 5-n is 2 or greater, there may be multiple R 10 They may be the same or different.

[0090] General formula (G4) differs from general formula (G3) in that the substitution positions of both substituents, a phenyl group with a trisubstituted silyl group and a substituted or unsubstituted pyridinyl group, are limited to the meta position relative to the triazine or pyrimidine. By having a structure with a phenyl group with a trisubstituted silyl group and a substituted or unsubstituted pyridinyl group at the substitution position shown in general formula (G4), steric hindrance due to the proximity of substituents can be suppressed, and the stability of the molecule can be improved. Furthermore, compared to the case where substitution is at the para position, a decrease in the LUMO level can be avoided. In addition, it is preferable because it can suppress the elongation of the conjugation of the unsaturated bond and further lower the refractive index. In this case, R 12 ~R 14 It is preferable for it to be hydrogen (including deuterium) as it is more stable.

[0091] In the organic compounds represented by the above general formulas, n is more preferably 2 or 3, and even more preferably 2. This prevents steric hindrance caused by the proximity of trisubstituted silyl groups, thus preventing the molecule from becoming unstable and resulting in a stable organic compound. In this case, R 8 and R 10 It is preferable that the element be hydrogen (including deuterium) because it is more stable.

[0092] Furthermore, one aspect of the present invention is an organic compound represented by the general formula (G5).

[0093] [ka]

[0094] In the general formula (G5), Q 1 ~Q 3 Each independently represents N or CH (including CD), and Q 1 ~Q 3 At least two of them are N, and R 1 ~R 6 Each independently represents an alkyl group or phenyl group having 1 to 6 carbon atoms, R 8 ~R 10 Each of these independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms, R 12 ~R 24 Each independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, R 25 ~R 28 Each of these independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms.

[0095] General formula (G5) differs from general formula (G4) in the number (n) of trisubstituted silyl groups and in that the substitution positions are limited. By having a structure with two trisubstituted silyl groups at the substitution positions shown in general formula (G5), it is possible to prevent the molecule from becoming unstable due to steric hindrance between the trisubstituted silyl groups, thus making it possible to obtain a stable organic compound.

[0096] In the organic compounds represented by the above general formulas, R 25 ~R 28 It is more preferable that at least one of these is an alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 3 to 10 carbon atoms. This can lower the refractive index of the organic compound.

[0097] Furthermore, in the organic compounds represented by the above general formulas, Q 1 ~Q 3 However, it is more preferable if all of them are nitrogen. This can improve the electron transport properties of the organic compound.

[0098] Next, specific examples of substituents that can be applied to the organic compounds represented by the above general formulas will be described. However, the groups that can be applied to the above general formulas are not limited to the specific examples described below. Also, in the specific examples described below, some or all of the hydrogens may be deuterium.

[0099] Alkyl alkyl groups with 1 to 6 carbon atoms A C1 to C6 alkyl group refers to a monovalent group obtained by removing one hydrogen (H) from an alkane having C1 to C6. Specific examples include methyl, ethyl, propyl, isopropyl, butyl, sec-butyl, isobutyl, tert-butyl, pentyl, isopentyl, sec-pentyl, tert-pentyl, neopentyl, hexyl, isohexyl, sec-hexyl, tert-hexyl, neohexyl, 3-methylpentyl, 2-methylpentyl, 2-ethylbutyl, 1,2-dimethylbutyl, and 2,3-dimethylbutyl groups. When the alkyl group is a methyl group, there is less steric hindrance due to the proximity of substituents (alkyl groups), which contributes to improved molecular stability and is therefore preferable. Furthermore, among alkyl groups, the methyl group is preferred because its small steric size makes it less likely to inhibit carrier transport. When the alkyl group has two or more carbon atoms, the refractive index of the organic compound can be further reduced.

[0100] Cycloalkyl groups with 3 to 10 carbon atoms Cycloalkyl groups having 3 to 10 carbon atoms refer to monovalent groups obtained by removing one hydrogen atom from monocyclic or polycyclic cycloalkanes having 3 to 10 carbon atoms. Specific examples include cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, norbornyl, bicyclo[2,2,2]octyl, decahydronaphthyl, and adamantyl groups. Among cycloalkyl groups, those with 6 or more carbon atoms are preferred over cycloalkyl groups with 5 or fewer carbon atoms because they lower the refractive index of organic compounds and improve the glass transition temperature (Tg). Among these, the cyclohexyl group is preferred because it is inexpensive.

[0101] Aryl groups with 6 to 30 carbon atoms An aryl group having 6 to 30 carbon atoms is a monovalent group obtained by removing one hydrogen atom from one of the carbon atoms forming the ring of a monocyclic or polycyclic aromatic compound having 6 to 30 carbon atoms. Specific examples include the phenyl group, o-tolyl group, m-tolyl group, p-tolyl group, mesityl group, biphenyl-2-yl group (o-biphenyl group), biphenyl-3-yl group (m-biphenyl group), biphenyl-4-yl group (p-biphenyl group), 1-naphthyl group, 2-naphthyl group, phenylnaphthyl group, naphthylphenyl group, terphenyl group, fluorenyl group, 9,9-dimethylfluorenyl group, quaterphenyl group, spirobifluorenyl group, phenanthryl group, anthryl group, binaphthylphenyl group, and fluoranthenyl group. When an aryl group having 6 to 30 carbon atoms has substituents, specific examples of such substituents include alkyl groups having 1 to 6 carbon atoms, cycloalkyl groups having 3 to 10 carbon atoms, and phenyl groups. Among aryl groups, aryl groups having a six-membered ring are preferred because they are stable and reliable.

[0102] Heteroaryl groups with 3 to 30 carbon atoms A heteroaryl group having 3 to 30 carbon atoms refers to a monovalent group obtained by removing one hydrogen atom from one of the carbon atoms forming the ring of a monocyclic or polycyclic heterocyclic aromatic compound having 3 to 30 carbon atoms. Specific examples include carbazolyl group, dibenzothiophenyl group, dibenzofuranyl group, benzocarbazolyl group, naphthobenzothiophenyl group, naphthobenzofuranyl group, dibenzocarbazolyl group, dinaphthothiophenyl group, dinaphthofuranyl group, triazinyl group, pyrimidinyl group, pyrazinyl group, triazolyl group, pyridinyl group, benzoflopyrimidinyl group, benzothiopyrimidinyl group, benzoflopyramidinyl group, benzothiopyramidinyl group, benzothiopyramidinyl group, bicarbazolyl group, etc. When a heteroaryl group having 3 to 30 carbon atoms has substituents, specific examples of such substituents include alkyl groups having 1 to 6 carbon atoms, cycloalkyl groups having 3 to 10 carbon atoms, and phenyl groups. Among heteroaryl groups, those having a six-membered ring are preferred because they are stable and reliable. Furthermore, it is preferable for the heteroaryl group to contain two or more nitrogen atoms, as this improves electron transport properties. It is also preferable for the heteroaryl group to have only one nitrogen atom, as this results in a lower refractive index.

[0103] The above are specific examples of substituents that can be applied to each organic compound represented by the general formula.

[0104] Specific examples of organic compounds according to one aspect of the present invention, represented by the above general formulas, include organic compounds represented by the following structural formulas (100) to (122). However, organic compounds according to one aspect of the present invention are not limited to organic compounds represented by the following structural formulas.

[0105] [ka]

[0106] [ka]

[0107] [ka]

[0108] Next, as an example of a method for synthesizing an organic compound according to one aspect of the present invention, a method for synthesizing an organic compound represented by general formula (G1) will be described.

[0109] The organic compound represented by general formula (G1) can be obtained by first synthesizing a boron compound (B2) from a halogen compound (B1) as shown in the synthesis scheme (A-1) below, and then reacting the boron compound (B2) with a Si-containing halogen compound (B3) as shown in the synthesis scheme (A-2).

[0110] [ka]

[0111] In the above synthesis schemes (A-1) and (A-2), Q 1 ~Q 3 , R 1 ~R 3 , n, R 10 , R 11 ~R 24 The explanation for , is the same as in the general formula (G1) above, so it is omitted here. X represents chlorine, bromine, iodine, or a sulfonyloxy group. When X is a halogen, a larger atomic number is preferable as it increases the reactivity of the halogen compound (B1). Y represents a boronyl group. In addition, boronic acid esters such as pinacol boronic acid ester may be used as the boron compound (B2).

[0112] In the above synthesis scheme (A-1), a boron compound (B2) can be synthesized by coupling a halogen compound (B1) with a boron source under palladium catalysis. Examples of boron sources include bis(pinacolate)diboron and pinacolborane. Examples of palladium catalysts include [1,1'-bis(diphenylphosphino)ferrocene]palladium(II) dichloride dichloromethane adduct, palladium(II) acetate, and tris(dibenzylideneacetone)dipalladium(O). Examples of ligands for the palladium catalyst include 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl. Examples of bases include inorganic bases such as potassium acetate, potassium carbonate, and tripotassium phosphate. Examples of solvents include dimethyl sulfoxide, N,N-dimethylformamide, and 1,4-dioxane. Note that the reagents that can be used are not limited to these.

[0113] In addition, in the above synthesis scheme (A-1), a boron compound (B2) can also be obtained by reacting a halogen compound (B1), a lithium reagent, and a borate ester.

[0114] In the above synthesis scheme (A-2), an organic compound represented by general formula (G1) can be synthesized by coupling a boron compound (B2) and a Si-containing halogen compound (B3) under palladium catalysis. Examples of palladium catalysts include tetrakistriphenylphosphine palladium (O), palladium acetate (II), and tris(dibenzylideneacetone)dipalladium (O). Examples of ligands for the palladium catalyst include 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl, 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl, tri(ortho-tolyl)phosphine, and triphenylphosphine. Examples of bases include inorganic bases such as potassium acetate, potassium carbonate, sodium carbonate, and tripotassium phosphate. Examples of solvents include toluene, xylene, tetrahydrofuran, dioxane, ethylene glycol dimethyl ether, ethanol, and water. However, the reagents that can be used in this reaction are not limited to these reagents.

[0115] While organic compounds according to one aspect of the present invention can be synthesized as described above, the present invention is not limited thereto, and may be synthesized by other synthesis methods.

[0116] <How to find GSP_slope> Here, we will explain how to determine the GSP_slope of a film formed by vacuum deposition of an organic compound.

[0117] The phenomenon in which the surface potential of a deposited film increases in proportion to its thickness is called giant surface potential, as mentioned above. Generally, the slope when the surface potential of a deposited film measured by a Kelvin probe is plotted in the direction of film thickness is discussed as the magnitude of the giant surface potential, i.e., GSP_slope (mV / nm). However, when two different layers are stacked, the charge density (mC / m) accumulated at their interface is also a factor. 2The GSP_slope can be estimated by utilizing the fact that ) changes in relation to the GSP. The charge density accumulated at the interface can be obtained by CV (capacitance-voltage) measurement using a device structure that accumulates charge in one of the layers.

[0118] When two organic thin films with different SOPs (thin film 1 and thin film 2, where thin film 1 is on the anode side and thin film 2 is on the cathode side, and the anode is on the substrate side) are stacked and a voltage is applied, the following equation holds true if the carriers (stored charge) accumulated at the interface are electrons.

[0119]

number

[0120]

number

[0121] In equation (1), σ acc σ is the accumulated charge density. int V is the interfacial charge density. inj V is the electron injection voltage. th V is the threshold voltage, d1 is the thickness of thin film 1, and ε1 is the dielectric constant of thin film 1. inj , V th This can be estimated from the capacitance-voltage characteristics of the device. Also, the dielectric constant is the refractive index n. o Assuming that the square of (the value for a wavelength of 633 nm) is the relative permittivity, the value obtained by multiplying this by the permittivity of vacuum can be used. In this way, the V estimated from the capacitance-voltage characteristics inj , V th Then, using the dielectric constant ε1 of thin film 1 calculated from the refractive index, and the film thickness d1 of thin film 1, the interfacial charge density σ is calculated using equation (1). int It is possible to find this.

[0122] Next, in equation (2), P1 and P2 are the dimensions of thin film 1 and thin film 2 perpendicular to the substrate surface of the SOP, ε2 is the dielectric constant of thin film 2, and d2 is the film thickness of thin film 2. Here, from equation (1) above, the interfacial charge density σ intSince this can be determined, by using a material with a known GSP_slope as thin film 1, the GSP_slope of thin film 2 can be estimated.

[0123] Therefore, an example of fabricating a measurement device 1 using tris(8-quinolinolato)aluminum(III) (abbreviated as Alq3), for which the GSP_slope is known, as thin film 1, and mmTMSPh-mDMePyPTzn, an organic compound according to one aspect of the present invention, as thin film 2 is shown below. The GSP_slope of Alq3 measured using a Kelvin probe is 48 mV / nm, according to Non-Patent Literature 3. The chemical formulas of mmTMSPh-mDMePyPTzn and Alq3 are shown below.

[0124] [ka]

[0125] As shown in Figure 10, the measurement device 1 has a structure in which layers 952, 953, 954, 955, and 956 are sequentially stacked on an anode 951 formed on a glass substrate 950, and a cathode 957 is stacked on layer 956. The device structure of the measurement device 1 is shown in Table 1.

[0126] In the measurement device 1, layer 953 corresponds to thin film 1 and layer 954 corresponds to thin film 2. Layer 952 was formed by co-depositing N-(biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-9,9-dimethyl-9H-fluoren-2-amine (abbreviated as PCBBiF) and the electron-accepting organic compound OCHD-003 in a weight ratio of 1:0.1 (PCBBiF:OCHD-003) with a film thickness of 10 nm. Layer 953 was formed by depositing Alq3 to a thickness of 100 nm. Layer 954 was formed by depositing mmTMSPh-mDMePyPTzn to a film thickness of 100 nm. Layer 955 was formed by depositing 4,7-di-1-pyrrolidinyl-1,10-phenanthroline (abbreviated as Pyrrd-Phen) to a thickness of 1 nm.

[0127] [Table 1]

[0128] The cathode of each measurement device, starting from layer 952, was formed by vacuum deposition from the anode side, with the substrate temperature at room temperature and the deposition rate between 0.2 nm / s and 0.6 nm / s. Deposition was carried out without stopping the deposition process while forming one layer. When fabricating each measurement device, the deposition rate of each layer is preferably between 3 nm / min and 600 nm / min. Furthermore, the film thickness of each layer in the measurement device is preferably between 1 nm and 500 nm, and more preferably between 50 nm and 300 nm.

[0129] The capacitance-voltage characteristics of measuring device 1 are shown in Figure 22, and the current density-voltage characteristics are shown in Figure 23.

[0130] The electron injection voltage V of the measuring device 1 was determined using Figure 22 and equations (1) and (2). inj , interfacial charge density σ int , GSP_slope and the ordinary refractive index n of Alq3 used in the calculation oand the ordinary light refractive index n of mmTMSPh-mDMePyPTzn o、 The measured film thickness d1 of layer 953 and the threshold voltage V determined from FIG. 23 th are shown in Table 2. Note that the threshold voltage V th can also be determined from the capacitance-voltage characteristics. For the measured film thickness d1 of layer 953, a highly accurate value calculated by using the spectroscopic ellipsometry method for the actually formed film was adopted.

[0131]

Table 2

[0132] As shown in Table 2, from the measurement results of the measurement device 1, the GSP_slope was estimated to be 35.0 mV / nm. That is, it was low at 40.0 mV / nm or less, which is a more preferable value.

[0133] In this way, by fabricating a device in which a film formed of Alq3 with a known GSP_slope of the film and an organic compound for which the GSP_slope is to be determined are laminated and measuring the capacitance-voltage characteristics, the GSP_slope can be estimated.

[0134] In the above description, a method for calculating the GSP_slope of an organic compound used for an electron transport layer in which carriers are electrons has been described. However, when using the GSP_slope of an organic compound used for a hole transport layer in which carriers are holes, as shown in Non-Patent Document 4, it can be calculated in the same manner by using the following formula (3).

[0135]

Equation

[0136] It is preferable to select an organic compound to be used for each layer of the light-emitting device in consideration of the GSP_slope of the vapor-deposited film of the organic compound measured in advance by the above measurement method.

[0137] The configuration shown in this embodiment can be used in appropriate combination with the configurations shown in other embodiments.

[0138] (Embodiment 2) This embodiment describes a light-emitting device according to one aspect of the present invention.

[0139] In one embodiment of the present invention, an organic compound having a trisubstituted silyl group introduced into an electron-transporting skeleton can be used in the light-emitting device. More specifically, in one embodiment of the present invention, an organic compound having a π-electron-deficient heteroaromatic ring and a trisubstituted silyl group having 3 to 18 carbon atoms can be used in the light-emitting device. As described in Embodiment 1, such organic compounds have electron-transporting properties, a low refractive index of the deposited film, and a small GSP_Slope. Therefore, by using them in the electron transport layer of a light-emitting device, the luminescence efficiency of the light-emitting device can be increased and the driving voltage can be lowered.

[0140] When using the organic compound in the electron transport layer of a light-emitting device, it is preferable to use a mixed layer having the organic compound and a metal complex, as this improves the electron injection properties into the electron transport layer.

[0141] The trisubstituted silyl group having 3 to 18 carbon atoms in the organic compound is a group having a structure in which three alkyl or aryl groups with a total of 3 to 18 carbon atoms are bonded to silicon (Si). Specific examples include trimethylsilyl group, triethylsilyl group, tert-butyldimethylsilyl group, and triphenylsilyl group. Among these, trialkylsilyl groups having 3 to 18 carbon atoms, such as trimethylsilyl group, triethylsilyl group, and tert-butyldimethylsilyl group, are preferred because they can further lower the refractive index of the organic compound. In particular, organic compounds having a trimethylsilyl group are preferred because they can be synthesized inexpensively.

[0142] Examples of π-electron-deficient heteroaromatic rings in the organic compound include oxadiazole rings, triazole rings, benzimidazole rings, quinoxaline rings, dibenzoquinoxaline rings, quinazoline rings, phenanthroline rings, pyridine rings, diazine rings (including pyrimidine rings, pyrazine rings, and pyridazine rings), triazine rings, and phlodiazine rings. Among these, pyrimidine rings or triazine rings, which are six-membered monorings, are preferred because they have a lower refractive index compared to fused aromatic rings, while being stable and reliable with respect to carriers and excitations.

[0143] Furthermore, as an example of an organic compound having a π-electron-deficient heteroaromatic ring and a trisubstituted silyl group having 3 to 18 carbon atoms that can be used in a light-emitting device according to one aspect of the present invention, an organic compound represented by the following general formula (G0) can be mentioned.

[0144] [ka]

[0145] In the general formula (G0), Q 1 ~Q 3 Each independently represents N or CH, and Q 1 ~Q 3 At least two of them are N, and R 1 ~R 3 Each independently represents an alkyl group or phenyl group having 1 to 6 carbon atoms, n represents an integer between 1 and 5, and R 10 ~R 24 Each of these independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a trisubstituted silyl group having 3 to 18 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms. When n is 2 or more, multiple R 1 They may be the same or different. Multiple R 2 They may be the same or different. Multiple R 3 They may be the same or different. If 5-n is 2 or greater, there may be multiple R 10They may be the same or different.

[0146] Specific examples of the substituents applicable to the organic compound represented by the general formula (G0) are the same as those described in Embodiment 1, and thus the description thereof is omitted here.

[0147] In addition, as examples of the organic compound having a π-electron-deficient heteroaromatic ring and a trisubstituted silyl group having 3 to 18 carbon atoms, which can be used in the light-emitting device of one aspect of the present invention, the organic compounds represented by the general formulas (G1) to (G5) described in Embodiment 1 can be used.

[0148] When an organic compound having a π-electron-deficient heteroaromatic ring and a trisubstituted silyl group having 3 to 18 carbon atoms is used as a mixed layer with a metal complex, the metal complex is preferably an organic complex having an alkali metal. Examples of the organic complex having an alkali metal include 8-quinolinolato-lithium (abbreviation: Liq), 8-quinolinolato-sodium (abbreviation: Naq), 8-quinolinolato-potassium (abbreviation: Kq), and derivatives thereof, which can be represented by the following structural formulas. For example, an organic complex having an alkyl group such as a methyl group has a low refractive index and is preferable. When the second electron transport layer 114-2 contains such a substance, it is preferable because electrons can be easily injected from the second electrode 102. In addition, it is preferable because the electron transport property in the second electron transport layer 114-2 can be controlled.

[0149]

Chemical formula

[0150] In addition, when an organic compound having a π-electron-deficient heteroaromatic ring and a trisubstituted silyl group having 3 to 18 carbon atoms is used as a mixed layer with a metal complex in the electron transport layer, the electron transport layer is preferably in contact with the cathode. Alternatively, when an electron injection layer is provided between the electron transport layer and the cathode, the thickness of the electron injection layer is more preferably 5 nm or less. Thereby, the effect of electron transportability can be enhanced.

[0151] Next, the configuration of a light-emitting device according to one embodiment of the present invention will be described with reference to Figures 1(A) to 1(F).

[0152] ≪Basic Structure of Light-Emitting Devices≫ The basic structure of a light-emitting device will be described. Figure 1(A) shows a light-emitting device having an EL layer containing a light-emitting layer between a pair of electrodes. Specifically, it has a structure in which an EL layer 103 is sandwiched between a first electrode 101 and a second electrode 102.

[0153] Furthermore, Figure 1(B) shows a light-emitting device with a stacked structure (tandem structure) having multiple (two layers in Figure 1(B)) EL layers (103a, 103b) between a pair of electrodes, and a charge generation layer 106 between the EL layers. A light-emitting device with a tandem structure can realize a highly efficient display device without changing the amount of current.

[0154] The charge generation layer 106 has the function of injecting electrons into one EL layer (103a or 103b) and holes into the other EL layer (103b or 103a) when a potential difference is created between the first electrode 101 and the second electrode 102. Therefore, in Figure 1(B), when a voltage is applied to the first electrode 101 such that its potential is higher than that of the second electrode 102, electrons are injected from the charge generation layer 106 into the EL layer 103a and holes are injected into the EL layer 103b.

[0155] Furthermore, from the viewpoint of light extraction efficiency, it is preferable that the charge generation layer 106 is transparent to visible light (specifically, the transmittance of visible light to the charge generation layer 106 is 40% or more). In addition, the charge generation layer 106 can function even if its conductivity is lower than that of the first electrode 101 and the second electrode 102.

[0156] Figure 1(C) shows the laminated structure of the EL layer 103 of a light-emitting device according to one embodiment of the present invention. In this case, the first electrode 101 functions as an anode and the second electrode 102 functions as a cathode. The EL layer 103 has a structure in which a hole injection layer 111, a hole transport layer 112, a light-emitting layer 113, an electron transport layer 114, and an electron injection layer 115 are sequentially laminated on the first electrode 101. The light-emitting layer 113 may be a configuration in which multiple light-emitting layers of different emission colors are laminated. For example, a light-emitting layer containing a red light-emitting material, a light-emitting layer containing a green light-emitting material, and a light-emitting layer containing a blue light-emitting material may be laminated, or laminated via a layer having a carrier transport material. Alternatively, a combination of a light-emitting layer containing a yellow light-emitting material and a light-emitting layer containing a blue light-emitting material may be used. However, the laminated structure of the light-emitting layer 113 is not limited to the above. For example, the light-emitting layer 113 may be configured by stacking multiple light-emitting layers of the same emission color. For example, it may be a structure in which a first light-emitting layer containing a blue light-emitting material and a second light-emitting layer containing a blue light-emitting material are stacked, or stacked via a layer having a carrier transport material. In the case of a configuration in which multiple light-emitting layers of the same emission color are stacked, it may be possible to improve the operating life, i.e., improve reliability, compared to a single-layer configuration. Also, even when there are multiple EL layers as in the tandem structure shown in Figure 1(B), each EL layer is stacked sequentially from the anode side as described above. Furthermore, if the first electrode 101 is the cathode and the second electrode 102 is the anode, the stacking order of the EL layers 103 is reversed. Specifically, on the first electrode 101, which is the cathode, 111 is an electron injection layer, 112 is an electron transport layer, 113 is a light-emitting layer, 114 is a hole transport layer, and 115 is a hole injection layer.

[0157] The light-emitting layers 113 contained in the EL layers (103, 103a, 103b) each contain a light-emitting material and a combination of multiple materials as appropriate, and can be configured to produce fluorescence emission or phosphorescence emission exhibiting a desired emission color. Alternatively, a configuration can be used in which different emission colors can be obtained from each of the multiple EL layers (103a, 103b) shown in Figure 1(B). In this case, the light-emitting material and other materials used in each light-emitting layer can be different materials.

[0158] Furthermore, in a light-emitting device according to one aspect of the present invention, for example, by using a reflective electrode as the first electrode 101 shown in Figure 1(C) and a semi-transparent / semi-reflective electrode as the second electrode 102, and by using a micro-cavity structure, the light emitted from the light-emitting layer 113 contained in the EL layer 103 can be resonated between the two electrodes, thereby strengthening the light emitted from the second electrode 102.

[0159] Furthermore, if the first electrode 101 of the light-emitting device is a reflective electrode consisting of a laminated structure of a reflective conductive material and a translucent conductive material (transparent conductive film), optical adjustment can be performed by controlling the film thickness of the transparent conductive film. Specifically, it is preferable to adjust the optical distance (product of film thickness and refractive index) between the first electrode 101 and the second electrode 102 to be mλ / 2 (where m is an integer of 1 or more) or close to it, with respect to the wavelength λ of light obtained from the light-emitting layer 113.

[0160] Furthermore, in order to amplify the light obtained from the light-emitting layer 113 at a desired wavelength (wavelength: λ), it is preferable to adjust the optical distance from the first electrode 101 to the region where light emission from the light-emitting layer 113 is obtained (light-emitting region), and the optical distance from the second electrode 102 to the region where light emission from the light-emitting layer 113 is obtained (light-emitting region), so that they are (2m'+1)λ / 4 (where m' is an integer of 1 or more) or near that value. The light-emitting region referred to here is the region in the light-emitting layer 113 where holes and electrons recombine.

[0161] By performing such optical adjustments, the spectrum of specific monochromatic light obtained from the light-emitting layer 113 can be narrowed, resulting in emission with good color purity.

[0162] However, in the above case, the optical distance between the first electrode 101 and the second electrode 102 can be precisely defined as the total thickness from the reflective region of the first electrode 101 to the reflective region of the second electrode 102. However, since it is difficult to precisely determine the reflective regions of the first electrode 101 and the second electrode 102, the above effect can be sufficiently obtained by assuming that any position on the first electrode 101 and the second electrode 102 is a reflective region. Furthermore, the optical distance between the first electrode 101 and the light-emitting layer can be precisely defined as the optical distance between the reflective region of the first electrode 101 and the light-emitting region of the light-emitting layer. However, since it is difficult to precisely determine the reflective region of the first electrode 101 and the light-emitting region of the light-emitting layer, the above effect can be sufficiently obtained by assuming that any position on the first electrode 101 is a reflective region and any position on the light-emitting layer is a light-emitting region.

[0163] Figure 1(D) shows a modified example of the laminated structure shown in Figure 1(C). In this example as well, the first electrode 101 functions as the anode and the second electrode 102 functions as the cathode. In this modified example, the hole transport layer 112 and the electron transport layer 114 each have a two-layer laminated structure. That is, the EL layer 103 has a structure in which the hole injection layer 111, the first hole transport layer 112-1, the second hole transport layer 112-2, the light-emitting layer 113, the second electron transport layer 114-2, the first electron transport layer 114-1, and the electron injection layer 115 are sequentially stacked on the first electrode 101. The light-emitting layer 113 is located between the first electrode 101 and the second electrode 102. The first hole transport layer 112-1 is located between the first electrode 101 and the light-emitting layer 113. Furthermore, the first electron transport layer 114-1 is located between the light-emitting layer 113 and the second electrode 102. The hole injection layer 111 is located between the first electrode 101 and the hole transport layer 112. The electron injection layer 115 is located between the electron transport layer 114 and the second electrode 102. The second hole transport layer 112-2 is located between the first hole transport layer 112-1 and the light-emitting layer 113. In other words, the second electron transport layer 114-2 is located between the light-emitting layer 113 and the first electron transport layer 114-1. When the EL layer 103 has such a layered structure, it is preferable that one or more of the electron injection layer 115, electron transport layer 114, and light-emitting layer 113 contain an organic compound represented by general formula (G1) to general formula (G5). In particular, if the electron transport layer 114 contains an organic compound represented by general formula (G1) to general formula (G5), it is preferable because it can be expected to increase the efficiency of the light-emitting device and reduce the driving voltage.

[0164] The second hole transport layer 112-2 is provided, for example, to prevent electrons from penetrating from the light-emitting layer 113 to the first electrode 101. Therefore, the second hole transport layer 112-2 can also be called an electron blocking layer. The second electron transport layer 114-2 is provided, for example, to prevent holes from penetrating from the light-emitting layer 113 to the second electrode 102. Therefore, the second electron transport layer 114-2 can also be called a hole blocking layer. The second electron transport layer 114-2, which is in contact with the light-emitting layer 113, can use an organic compound represented by general formula (G1) to general formula (G5). Furthermore, using an organic compound represented by general formula (G1) to general formula (G5) in the first electron transport layer 114-1 is particularly preferable, as it can be expected to increase the efficiency and decrease the driving voltage of the light-emitting device.

[0165] The light-emitting device shown in Figure 1(E) is a light-emitting device having a tandem structure and a microcavity structure, which allows for the extraction of light of different wavelengths (monochromatic light) from each EL layer (103a, 103b). Therefore, color separation (e.g., RGB) to obtain different emission colors is unnecessary. Consequently, high resolution can be easily achieved. It can also be combined with a colored layer (color filter). Furthermore, it is possible to strengthen the emission intensity in the front direction at a specific wavelength, thereby reducing power consumption.

[0166] The light-emitting device shown in Figure 1(F) is an example of a tandem-structured light-emitting device shown in Figure 1(B). As shown in the figure, it has a structure in which three EL layers (103a, 103b, 103c) are stacked with charge generation layers (106a, 106b) in between. Each of the three EL layers (103a, 103b, 103c) has a light-emitting layer (113a, 113b, 113c), and the light-emitting colors of each light-emitting layer can be freely combined. For example, light-emitting layer 113a can be blue, light-emitting layer 113b can be red, green, or yellow, and light-emitting layer 113c can be blue. Alternatively, light-emitting layer 113a can be red, light-emitting layer 113b can be blue, green, or yellow, and light-emitting layer 113c can be red.

[0167] In the light-emitting device according to one aspect of the present invention described above, at least one of the first electrode 101 and the second electrode 102 is a light-transmitting electrode (such as a transparent electrode or a semi-transparent / semi-reflective electrode). If the light-transmitting electrode is a transparent electrode, the transmittance of visible light of the transparent electrode shall be 40% or more. If it is a semi-transparent / semi-reflective electrode, the reflectance of visible light of the semi-transparent / semi-reflective electrode shall be 20% or more and 80% or less, preferably 40% or more and 70% or less. Furthermore, the resistivity of these electrodes shall be 1 × 10⁻⁶. -2 It is preferable to keep it below Ωcm.

[0168] Furthermore, in the light-emitting device according to one aspect of the present invention described above, if one of the first electrode 101 and the second electrode 102 is a reflective electrode (reflective electrode), the visible light reflectance of the reflective electrode is 40% or more and 100% or less, preferably 70% or more and 100% or less. In addition, the resistivity of this electrode is 1 × 10⁻⁶. -2 It is preferable to keep it below Ωcm.

[0169] ≪Specific structure of a light-emitting device≫ Next, a specific structure of a light-emitting device according to one aspect of the present invention will be described. Here, we will use Figure 1(E), which has a tandem structure, for explanation. The same applies to the EL layer configuration for the single-structure light-emitting devices shown in Figures 1(A) and 1(C). Furthermore, if the light-emitting device shown in Figure 1(E) has a microcavity structure, the first electrode 101 is formed as a reflective electrode, and the second electrode 102 is formed as a semi-transparent / semi-reflective electrode. Thus, one or more desired electrode materials can be used and formed as a single layer or in a stacked manner. The second electrode 102 is formed after the EL layer 103b is formed, by selecting an appropriate material.

[0170] <First electrode and second electrode> As materials for forming the first electrode 101 and the second electrode 102, any combination of the following materials can be used as long as the functions of both electrodes described above are met. For example, metals, alloys, electrically conductive compounds, and mixtures thereof can be used as appropriate. Specifically, these include In-Sn oxide (also called ITO), In-Si-Sn oxide (also called ITSO), In-Zn oxide, and In-W-Zn oxide. In addition, metals such as aluminum (Al), titanium (Ti), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), gallium (Ga), zinc (Zn), indium (In), tin (Sn), molybdenum (Mo), tantalum (Ta), tungsten (W), palladium (Pd), gold (Au), platinum (Pt), silver (Ag), yttrium (Y), neodymium (Nd), and alloys containing these in appropriate combinations can also be used. In addition, elements belonging to Group 1 or Group 2 of the periodic table not exemplified above (for example, lithium (Li), cesium (Cs), calcium (Ca), strontium (Sr)), rare earth metals such as europium (Eu) and ytterbium (Yb), and alloys containing these in appropriate combinations, as well as graphene and other materials can be used.

[0171] In the light-emitting device shown in Figure 1(E), when the first electrode 101 is the anode, the hole injection layer 111a and the hole transport layer 112a of the EL layer 103a are sequentially laminated on the first electrode 101 by vacuum deposition. After the EL layer 103a and the charge generation layer 106 are formed, the hole injection layer 111b and the hole transport layer 112b of the EL layer 103b are similarly sequentially laminated on the charge generation layer 106.

[0172] <Hole injection layer> The hole injection layers (111, 111a, 111b) are layers that inject holes from the first electrode 101, which is the anode, and the charge generation layers (106, 106a, 106b) into the EL layers (103, 103a, 103b), and are layers that contain organic acceptor material and material with high hole injection potential.

[0173] Organic acceptor materials are materials that can generate holes in an organic compound by separating its charge from other organic compounds whose LUMO level and HOMO level are close in value. Therefore, compounds having electron-withdrawing groups (halogen groups or cyano groups), such as quinodimethane derivatives, chloranil derivatives, and hexaazatriphenylene derivatives, can be used as organic acceptor materials. For example, 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviated as F4-TCNQ), 3,6-difluoro-2,5,7,7,8,8-hexacyanoquinodimethane, chloranil, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexazatriphenylene (abbreviated as HAT-CN), 1,3,4,5,7,8-hexafluorotetracyano-naphthoquinodimethane (abbreviated as F6-TCNNQ), 2-(7-dicyanomethylene-1,3,4,5,6,8,9,10-octafluoro-7H-pyrene-2-ylidene)malononitrile, etc. can be used. Furthermore, among organic acceptor materials, compounds in which an electron-withdrawing group is bonded to a condensed aromatic ring having multiple heteroatoms, such as HAT-CN, are particularly suitable because they have high acceptability and stable film properties with respect to heat. In addition, radialene derivatives having an electron-withdrawing group (especially a halogen group such as a fluoro group or a cyano group) [3] are also preferred because they have very high electron-accepting properties. Specifically, α,α',α''-1,2,3-cyclopropanetriylidenates[4-cyano-2,3,5,6-tetrafluorobenzeneacetonitrile], α,α',α''-1,2,3-cyclopropanetriylidenates[2,6-dichloro-3,5-difluoro-4-(trifluoromethyl)benzeneacetonitrile], and α,α',α''-1,2,3-cyclopropanetriylidenates[2,3,4,5,6-pentafluorobenzeneacetonitrile] can be used.

[0174] Furthermore, as materials with high hole injection potential, oxides of metals belonging to groups 4 through 8 of the periodic table (such as molybdenum oxide, vanadium oxide, ruthenium oxide, tungsten oxide, manganese oxide, and other transition metal oxides) can be used. Specifically, examples include molybdenum oxide, vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, tungsten oxide, manganese oxide, and rhenium oxide. Among these, molybdenum oxide is preferred because it is stable in the atmosphere, has low hygroscopicity, and is easy to handle. In addition, perylenetetracarboxylic acid derivatives such as diquinoxalino[2,3-a:2',3'-c]phenazine (abbreviated as HATNA), 2,3,8,9,14,15-hexafluorodiquinoxalino[2,3-a:2',3'-c]phenazine (abbreviated as HATNA-F6), 3,4,9,10-perylenetetracarboxylic acid diimide (abbreviated as PTCDI), and 3,4,9,10-perylenetetracarboxyl-bis-benzimidazole (abbreviated as PTCBI), (C 60 -Ih)[5,6]Fullerene (abbreviation: C 60 ), (C 70 -D5h)[5,6]Fullerene (abbreviation: C 70 Organic compounds such as phthalocyanine (abbreviated as H2Pc), metal phthalocyanines containing copper, zinc, cobalt, iron, chromium, nickel, etc., such as copper phthalocyanine (abbreviated as CuPc), zinc phthalocyanine (abbreviated as ZnPc), cobalt phthalocyanine (abbreviated as CoPc), iron phthalocyanine (abbreviated as FePc), tin phthalocyanine (abbreviated as SnPc), tin phthalocyanine oxide (abbreviated as SnOPc), titanium phthalocyanine oxide (abbreviated as TiOPc), and vanadium phthalocyanine oxide (abbreviated as VOPc), and their derivatives can be used. In particular, phthalocyanine-based metal complexes such as CuPc or ZnPc, or 2,3,8,9,14,15-hexafluorodiquinoxalino[2,3-a:2',3'-c]phenazine are preferred. Among these, CuPc and ZnPc are preferred because they are inexpensive and have good properties. Furthermore, ZnPc has a low diffusion coefficient with respect to silicon, reducing the risk of metal diffusion affecting semiconductor properties. Therefore, it is particularly suitable for application in display devices using silicon semiconductors.

[0175] In addition to the above materials, the low molecular weight compounds include 4,4',4''-tris(N,N-diphenylamino)triphenylamine (abbreviation: TDATA), 4,4',4''-tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine (abbreviation: m-MTDATA), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), N,N'-bis[4-bis(3-methylphenyl)aminophenyl]-N,N'-diphenyl-4,4'-diaminobiphenyl (abbreviation: DNTPD), and 1,3,5-tris[ Aromatic amine compounds such as N-(4-diphenylaminophenyl)-N-phenylamino]benzene (abbreviation: DPA3B), 3-[N-(9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3,6-bis[N-(9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA2), and 3-[N-(1-naphthyl)-N-(9-phenylcarbazole-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1) can be used.

[0176] Furthermore, polymer compounds (oligomers, dendrimers, polymers, etc.) such as poly(N-vinylcarbazole) (abbreviated as PVK), poly(4-vinyltriphenylamine) (abbreviated as PVTPA), poly[N-(4-{N'-[4-(4-diphenylamino)phenyl]phenyl-N'-phenylamino}phenyl)methacrylamide] (abbreviated as PTPDMA), and poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)benzidine] (abbreviated as Poly-TPD) can be used. Alternatively, polymer compounds to which acids such as poly(3,4-ethylenedioxythiophene) / polystyrene sulfonic acid (abbreviated as PEDOT / PSS) and polyaniline / polystyrene sulfonic acid (abbreviated as PAni / PSS) have been added can also be used.

[0177] Furthermore, as a material with high hole injection capabilities, a mixed material containing a hole transport material and the aforementioned organic acceptor material (electron-accepting material) can also be used. In this case, electrons are extracted from the hole transport material by the organic acceptor material, generating holes in the hole injection layer 111, and these holes are injected into the light-emitting layer 113 via the hole transport layer 112. The hole injection layer 111 may be formed as a single layer of a mixed material containing a hole transport material and an organic acceptor material (electron-accepting material), or it may be formed by laminating the hole transport material and the organic acceptor material (electron-accepting material) in separate layers.

[0178] Furthermore, for hole-transporting materials, the hole mobility at which the square root of the electric field strength [V / cm] is 600 is 1 × 10⁻⁶. -6 cm 2 A material having a hole mobility of / Vs or higher is preferred. However, any material that has higher hole transport than electron transport can be used.

[0179] Furthermore, as hole-transporting materials, materials with high hole-transporting properties such as compounds having a π-electron-rich heteroaromatic ring (e.g., carbazole derivatives, furan derivatives, or thiophene derivatives) and aromatic amines (organic compounds having an aromatic amine skeleton) are preferred.

[0180] Examples of the above-mentioned carbazole derivatives (organic compounds having a carbazole ring) include bicarbazole derivatives (for example, 3,3'-bicarbazole derivatives) and aromatic amines having a carbazolyl group.

[0181] Furthermore, the above bicarbazole derivatives (for example, 3,3'-bicarbazole derivatives) specifically include 3,3'-bis(9-phenyl-9H-carbazole) (abbreviation: PCCP), 9,9'-bis(biphenyl-4-yl)-3,3'-bi-9H-carbazole (abbreviation: BisBPCz), 9,9'-bis(biphenyl-3-yl)-3,3'-bi-9H-carbazole (abbreviation: BismBPCz), and 9-(biphenyl-3-yl)-9'-(biphenyl-4-yl)-9H,9'H-3,3'- Examples include bicarbazole (abbreviated as mBPCCBP), 9-(2-naphthyl)-9'-phenyl-3,3'-bi-9H-carbazole (abbreviated as βNCCP), 9-(3-biphenyl)-9'-(2-naphthyl)-3,3'-bi-9H-carbazole (abbreviated as βNCCmBP), 9-(4-biphenyl)-9'-(2-naphthyl)-3,3'-bi-9H-carbazole (abbreviated as βNCCBP), and 9,9'-di-2-naphthyl-3,3'-9H,9'H-bicarbazole (abbreviated as BisβNCz).

[0182] Furthermore, examples of aromatic amines having the above-mentioned carbazolyl group include 4-phenyl-4'-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviated as PCBA1BP), N-(biphenyl-4-yl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-9-phenyl-9H-carbazole-3-amine (abbreviated as PCBiF), N-(biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-9,9-dimethyl-9H-fluoren-2-amine (abbreviated as Name: PCBBiF), N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]bis(9,9-dimethyl-9H-fluoren-2-yl)amine (abbreviation: PCBFF), N-(1,1'-biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-9,9-dimethyl-9H-fluoren-4-amine, N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-(9,9-dimethyl-9H-fluoren-2-yl)-9,9-dimethyl-9H-fluoren -4-amine, N-(1,1'-biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-9,9-diphenyl-9H-fluoren-2-amine, N-(1,1'-biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-9,9-diphenyl-9H-fluoren-4-amine, N-(1,1'-biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-9,9'-spirobio(9H-fluoren) )-2-amine, N-(1,1'-biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-9,9'-spirobi(9H-fluorene)-4-amine, N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-N-(1,1':3',1''-terphenyl-4-yl)-9,9-dimethyl-9H-fluorene-2-amine, N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-N-(1,1':4',1''-terphenyl-4-yl)-9,9-dimethyl-9H-fluoren-2-amine, N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-N-(1,1':3',1''-terphenyl-4-yl)-9,9-dimethyl-9H-fluoren-4-amine, N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-N-(1,1':4',1''-terphenyl-4-yl)-9,9-dimethyl-9H-fluoren-4-amine, 4,4'-diphenyl-4''-(9-phenyl-9H-carbazole-3-yl)triphenyl Luamine (abbreviation: PCBBi1BP), 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBANB), 4,4'-di(1-naphthyl)-4''-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBNBB), 4-phenyldiphenyl-(9-phenyl-9H-carbazole-3-yl)amine (abbreviation: PCA1BP), N,N'-bis(9-phenylcarbazole-3-yl)-N,N'-diphenylbenzene-1,3-diamine (Abbreviation: PCA2B), N,N',N''-triphenyl-N,N',N''-tris(9-phenylcarbazole-3-yl)benzene-1,3,5-triamine (Abbreviation: PCA3B), 9,9-dimethyl-N-phenyl-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]fluoren-2-amine (Abbreviation: PCBAF), N-phenyl-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-9,9'-spirobio[9H-fluoren]-2-amine (Abbreviation: PCBASF), PC zPCA1, PCzPCA2, PCzPCN1, 3-[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA1), 3,6-bis[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA2), 3,6-bis[N-(4-diphenylaminophenyl)-N-(1-naphthyl)amino]-9-phenylcarbazole (abbreviation: PCzTPN2), N-(9,9-spirobio[9H-fluoren]-2-yl)-N,Examples include 9-diphenylcarbazole-3-amine (abbreviated as PCASF), N-[4-(9H-carbazole-9-yl)phenyl]-N-(4-phenyl)phenylaniline (abbreviated as YGA1BP), N,N'-bis[4-(carbazole-9-yl)phenyl]-N,N'-diphenyl-9,9-dimethylfluoren-2,7-diamine (abbreviated as YGA2F), and 4,4',4''-tris(carbazole-9-yl)triphenylamine (abbreviated as TCTA).

[0183] In addition to the above, other carbazole derivatives include 9-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]phenanthrene (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), and 3,6-bi Examples include su(3,5-diphenylphenyl)-9-phenylcarbazole (abbreviated as CzTP), 1,3,5-tris[4-(N-carbazolyl)phenyl]benzene (abbreviated as TCPB), 9-[4-(10-phenyl-9-antryl)phenyl]-9H-carbazole (abbreviated as CzPA), and 9-[3-(triphenylsilyl)phenyl]-3,9'-bi-9H-carbazole (abbreviated as PSiCzCz).

[0184] Furthermore, specific examples of the above-mentioned furan derivatives (organic compounds having a furan ring) include 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzofuran) (abbreviation: DBF3P-II) and 4-{3-[3-(9-phenyl-9H-fluoren-9-yl)phenyl]phenyl}dibenzofuran (abbreviation: mmDBFFLBi-II).

[0185] Furthermore, specific examples of the above-mentioned thiophene derivatives (organic compounds having a thiophene ring) include 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzothiophene) (abbreviated as DBT3P-II), 2,8-diphenyl-4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]dibenzothiophene (abbreviated as DBTFLP-III), and 4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]-6-phenyldibenzothiophene (abbreviated as DBTFLP-IV).

[0186] Furthermore, the above aromatic amines specifically include 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviated as NPB or α-NPD), N,N'-diphenyl-N,N'-bis(3-methylphenyl)-4,4'-diaminobiphenyl (abbreviated as TPD), N,N'-bis(9,9'-spirobio[9H-fluoren]-2-yl)-N,N'-diphenyl-4,4'-diaminobiphenyl (abbreviated as BSPB), and 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviated as 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)amino]-9H-fluoren-7-yl}phenylamine (abbreviation: DFLADFL), N-(9,9-dimethyl-2-diphenylamino-9H-fluoren-7-yl)diphenylamine (abbreviation: DPNF), N-(9,9-spirobio[9H-fluoren]-2- N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: DPASF), N,N'-diphenyl-N,N'-bis(4-diphenylaminophenyl)spirobi[9H-fluorene]-2,7-diamine (abbreviation: DPA2SF), 4,4',4''-tris[N-(1-naphthyl)-N-phenylamino]triphenylamine (abbreviation: 1'-TNATA), TDATA, 4,4',4''-tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine (abbreviation: m-MTDATA), N,N'-di(p- Ryl)-N,N'-diphenyl-p-phenylenediamine (abbreviation: DTDPPA), DPAB, DNTPD, DPA3B, N-(4-biphenyl)-6,N-diphenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BnfABP), N,N-bis(4-biphenyl)-6-phenylbenzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf), 4,4'-bis(6-phenylbenzo[b]naphtho[1,2-d]furan-8-yl)-4''-phenyltriphenylamine (abbreviation: BnfBB1BP), N,N-bis(4-biphenyl)benzo[b]naphtho[1,2-d]furan-6-amine (abbreviation: BBABnf(6)), N,N-bis(4-biphenyl)benzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf(8)), N,N-bis(4-biphenyl)benzo[b]naphtho[2,3-d]furan-4-amine (abbreviation: BBABnf(II)(4)), N,N-bis[4-(dibenzofuran-4 -yl)phenyl]-4-amino-p-terphenyl (abbreviation: DBfBB1TP), N-[4-(dibenzothiophen-4-yl)phenyl]-N-phenyl-4-biphenylamine (abbreviation: ThBA1BP), 4-(2-naphthyl)-4',4''-diphenyltriphenylamine (abbreviation: BBAβNB), 4-[4-(2-naphthyl)phenyl]-4',4''-diphenyltriphenylamine (abbreviation: BBAβ NBi), 4,4'-diphenyl-4''-([2,1'-binaphthyl]-6-yl)triphenylamine (abbreviation: BBAαNβNB), 4,4'-diphenyl-4''-([2,1'-binaphthyl]-7-yl)triphenylamine (abbreviation: BBAαNβNB-03), 4,4'-diphenyl-4''-(7-phenyl)naphthyl-2-yltriphenylamine (abbreviation: BBAPβNB-03), 4,4'-diphenyl Nyl-4''-([2,2'-binaphthyl]-6-yl)triphenylamine (abbreviation: BBA(βN2)B), 4,4'-diphenyl-4''-([2,2'-binaphthyl]-7-yl)triphenylamine (abbreviation: BBA(βN2)B-03), 4,4'-diphenyl-4''-([1,2'-binaphthyl]-4-yl)triphenylamine (abbreviation: BBAβNαNB), 4,4'-diphenyl-4''-([1,2'-binaphthyl]-5-yl)triphenylamine (abbreviation: BBAβNαNB-02), 4-(4-biphenylyl)-4'-(2-naphthyl)-4''-phenyltriphenylamine (abbreviation: TPBiAβNB), 4-(3-biphenylyl)-4'-[4-(2-naphthyl)phenyl]-4''-phenyltriphenylamine (abbreviation: mTPBiAβNBi), 4-(4-biphenylyl)-4'-[4-(2-naphthyl)phenyl]-4''-phenyltriphenylamine (abbreviation: TPBiAβNBi), 4-phenyl-4'-(1-naphthyl)triphenyl Phenylamine (abbreviation: αNBA1BP), 4,4'-bis(1-naphthyl)triphenylamine (abbreviation: αNBB1BP), 4,4'-diphenyl-4''-[4'-(carbazole-9-yl)biphenyl-4-yl]triphenylamine (abbreviation: YGTBi1BP), 4'-[4-(3-phenyl-9H-carbazole-9-yl)phenyl]tris(biphenyl-4-yl)amine (abbreviation: YGTBi1BP-02), 4-[4'-(carbazole-9-yl)biphenyl-4-yl]-4'-(2-naphthyl)-4''-phenyltriphenylamine Min (abbreviation: YGTBiβNB), N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-N-[4-(1-naphthyl)phenyl]-9,9'-spirobio[9H-fluorene]-2-amine (abbreviation: PCBNBSF), N,N-bis(biphenyl-4-yl)-9,9'-spirobio[9H-fluorene]-2-amine (abbreviation: BBASF), N,N-bis(biphenyl-4-yl)-9,9'-spirobio[9H-fluorene]-4-amine (abbreviation: BBASF(4)), N-(biphenyl-2-yl)-N-(9,9-dimethyl-9H -Fluoren-2-yl)-9,9'-spirobi[9H-fluoren]-4-amine (abbreviation: oFBiSF), N-(biphenyl-4-yl)-N-(9,9-dimethyl-9H-fluoren-2-yl)dibenzofuran-4-amine (abbreviation: FrBiF), N-[4-(1-naphthyl)phenyl]-N-[3-(6-phenyldibenzofuran-4-yl)phenyl]-1-naphthylamine (abbreviation: mPDBfBNBN), 4-phenyl-4'-[4-(9-phenylfluoren-9-yl)phenyl]triphenylamine (abbreviation: BPAFLBi), N,Examples include N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobio-9H-fluoren-4-amine, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobio-9H-fluoren-3-amine, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobio-9H-fluoren-2-amine, N,N-bis(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobio-9H-fluoren-1-amine, etc.

[0187] In addition, polymer compounds (oligomers, dendrimers, polymers, etc.) such as PVK, PVTPA, PTPDMA, and Poly-TPD can be used as hole transport materials. Alternatively, polymer compounds with added acids such as PEDOT / PSS and PAni / PSS can also be used.

[0188] However, the hole transport material is not limited to the above, and various known materials may be used as a hole transport material by combining one or more of them.

[0189] The hole injection layers (111, 111a, 111b) can be formed using various known film deposition methods, for example, by vacuum deposition.

[0190] <Hole transport layer> The hole transport layers (112, 112a, 112b) are layers that transport holes injected from the first electrode 101 by the hole injection layers (111, 111a, 111b) to the light-emitting layers (113, 113a, 113b). The hole transport layers (112, 112a, 112b) are layers containing a hole-transporting material. Therefore, the hole transport layers (112, 112a, 112b) can use the same hole-transporting material that can be used in the hole injection layers (111, 111a, 111b).

[0191] In one embodiment of the present invention, the same organic compound used in the hole transport layer (112, 112a, 112b) can be used in the light-emitting layer (113, 113a, 113b). Using the same organic compound in both the hole transport layer (112, 112a, 112b) and the light-emitting layer (113, 113a, 113b) is preferable because it allows for more efficient transport of holes from the hole transport layer (112, 112a, 112b) to the light-emitting layer (113, 113a, 113b).

[0192] <Luminous layer> The light-emitting layers (113, 113a, 113b) are layers containing a light-emitting material. The light-emitting material that can be used in the light-emitting layers (113, 113a, 113b) can be any material that exhibits a light-emitting color such as blue, purple, blue-violet, green, yellow-green, yellow, orange, or red. Furthermore, if there are multiple light-emitting layers, a configuration exhibiting different light-emitting colors can be achieved by using different light-emitting materials in each layer (for example, white light emission obtained by combining complementary light-emitting colors). Alternatively, when there are multiple light-emitting layers, each layer can exhibit the same color. In the case of a configuration where multiple light-emitting layers of the same color are stacked, reliability may be improved compared to a single-layer configuration. Furthermore, a stacked structure in which one of the light-emitting layers contains a different light-emitting material is also possible.

[0193] Furthermore, the light-emitting layers (113, 113a, 113b) may contain one or more types of organic compounds (host materials, etc.) in addition to the light-emitting substance (guest material).

[0194] Furthermore, when multiple host materials are used in the light-emitting layers (113, 113a, 113b), it is preferable to use a material with a larger energy gap than the energy gaps of the existing guest material and the first host material as the newly added second host material. It is also preferable that the lowest singlet excitation energy level (S1 level) of the second host material is higher than the S1 level of the first host material, and that the lowest triplet excitation energy level (T1 level) of the second host material is higher than the T1 level of the guest material. Furthermore, it is preferable that the lowest triplet excitation energy level (T1 level) of the second host material is higher than the T1 level of the first host material. With this configuration, an excitation complex can be formed using two types of host materials. In order to efficiently form the excitation complex, it is particularly preferable to combine a compound that readily accepts holes (hole transport material) with a compound that readily accepts electrons (electron transport material). This configuration also enables the simultaneous achievement of high efficiency, low voltage, and long lifespan.

[0195] The organic compounds used as the host material (including the first and second host materials) can be hole-transporting materials that can be used in the aforementioned hole-transporting layers (112, 112a, 112b), or electron-transporting materials that can be used in the electron-transporting layers (114, 114a, 114b) described later, as long as they satisfy the conditions for being a host material used in the light-emitting layer. They can also be excitation complexes composed of multiple types of organic compounds (the first and second host materials). Excitation complexes (also called exciplexes) that form excited states with multiple types of organic compounds have an extremely small energy difference between the S1 and T1 levels and function as thermally activated delayed fluorescence (TADF) materials that can convert triplet excitation energy into singlet excitation energy. Furthermore, as a combination of multiple organic compounds that form the excited complex, it is preferable, for example, that one has a π-electron-deficient heteroaromatic ring and the other has a π-electron-rich heteroaromatic ring. In addition, as a combination that forms the excited complex, one of the compounds may be an iridium, rhodium, or platinum-based organometallic complex, or a phosphorescent material such as a metal complex. The organic compounds having a trisubstituted silyl group described in Embodiment 1 and this embodiment can also be used as host materials because they possess electron transport properties.

[0196] There are no particular limitations on the luminescent material that can be used in the luminescent layers (113, 113a, 113b). A luminescent material that converts singlet excitation energy into visible light emission, or a luminescent material that converts triplet excitation energy into visible light emission, can be used.

[0197] <<Luminescent material that converts singlet excitation energy into light emission>> Examples of luminescent materials that can be used in the light-emitting layers (113, 113a, 113b) to convert singlet excitation energy into light include the following fluorescent materials (fluorescent materials). For example, pyrene derivatives, anthracene derivatives, triphenylene derivatives, fluorene derivatives, carbazole derivatives, dibenzothiophene derivatives, dibenzofuran derivatives, dibenzoquinoxaline derivatives, quinoxaline derivatives, pyridine derivatives, pyrimidine derivatives, phenanthrene derivatives, and naphthalene derivatives are examples. Pyrene derivatives are particularly preferred because they have a high luminescence quantum yield. Specific examples of pyrene derivatives include N,N'-bis(3-methylphenyl)-N,N'-bis[3-(9-phenyl-9H-fluoren-9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6mMemFLPAPrn), N,N'-diphenyl-N,N'-bis[4-(9-phenyl-9H-fluoren-9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6FLPAPrn), N,N'-bis(dibenzofuran-2-yl)-N,N'-diphenylpyrene-1,6-diamine (abbreviation: 1,6FrAPrn), N,N'-bis(dibenzothiophen-2-yl)-N, Examples include N'-diphenylpyrene-1,6-diamine (abbreviation: 1,6ThAPrn), N,N'-(pyrene-1,6-diyl)bis[(N-phenylbenzo[b]naphtho[1,2-d]furan)-6-amine] (abbreviation: 1,6BnfAPrn), N,N'-(pyrene-1,6-diyl)bis[(N-phenylbenzo[b]naphtho[1,2-d]furan)-8-amine] (abbreviation: 1,6BnfAPrn-02), and N,N'-(pyrene-1,6-diyl)bis[(6,N-diphenylbenzo[b]naphtho[1,2-d]furan)-8-amine] (abbreviation: 1,6BnfAPrn-03).

[0198] Also, 5,6-bis[4-(10-phenyl-9-antryl)phenyl]-2,2'-bipyridine (abbreviation: PAP2BPy), 5,6-bis[4'-(10-phenyl-9-antryl)biphenyl-4-yl]-2,2'-bipyridine (abbreviation: PAPP2BPy), N,N'-bis[4-(9H-carbazole-9-yl)phenyl]-N,N'-diphenylstilbene-4,4'-diamine (abbreviation: YGA2S), 4-(9H-carbazole (9-yl)-4'-(10-phenyl-9-anthryl)triphenylamine (abbreviation: YGAPA), 4-(9H-carbazole-9-yl)-4'-(9,10-diphenyl-2-anthryl)triphenylamine (abbreviation: 2YGAPPA), N,9-diphenyl-N-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole-3-amine (abbreviation: PCAPA), 4-(10-phenyl-9-anthryl)-4'- (9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBAPA), 4-[4-(10-phenyl-9-antryl)phenyl]-4'-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBAPBA), perylene, 2,5,8,11-tetra-tert-butylperylene (abbreviation: TBP), N,N''-(2-tert-butylanthracene-9,10-diyldi-4,1-phenyl) Nilen)bis(N,N',N'-triphenyl-1,4-phenylenediamine) (abbreviated as DPABPA), N,9-diphenyl-N-[4-(9,10-diphenyl-2-anthryl)phenyl]-9H-carbazole-3-amine (abbreviated as 2PCAPPA), N-[4-(9,10-diphenyl-2-anthryl)phenyl]-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviated as 2DPAPPA), etc. can be used.

[0199] Also, N-[9,10-bis(biphenyl-2-yl)-2-anthryl]-N,9-diphenyl-9H-carbazole-3-amine (abbreviation: 2PCABPhA), N-(9,10-diphenyl-2-anthryl)-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPA), N-[9,10-bis(biphenyl-2-yl)-2-anthryl]-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPABPhA), 9,10-bis(biphenyl-2-yl)-N-[ 4-(9H-carbazole-9-yl)phenyl]-N-phenylanthracene-2-amine (abbreviation: 2YGABPhA), N,N,9-triphenylanthracene-9-amine (abbreviation: DPhAPhA), coumarin 545T, N,N'-diphenylquinacridone (abbreviation: DPQd), rubren, 5,12-bis(biphenyl-4-yl)-6,11-diphenyltetracene (abbreviation: BPT), 2-(2-{2-[4-(dimethylamino)phenyl]ethenyl}-6-methyl-4H-pyran-4-ylidene)propanedinite Ryl (abbreviation: DCM1), 2-{2-methyl-6-[2-(2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinoridine-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCM2), N,N,N',N'-tetrakis(4-methylphenyl)tetracene-5,11-diamine (abbreviation: p-mPhTD), 7,14-diphenyl-N,N,N',N'-tetrakis(4-methylphenyl)acenaphtho[1,2-a]fluorantene-3,10-diamine (abbreviation: p-mPhA FD), 2-{2-isopropyl-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinoridine-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTI), 2-{2-tert-butyl-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinoridine-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTB), 2-(2,6-Bis{2-[4-(dimethylamino)phenyl]ethenyl}-4H-pyran-4-ylidene)propanedinitrile (abbreviation: BisDCM), 2-{2,6-Bis[2-(8-methoxy-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinoridine-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: BisDCJTM), 1,6BnfAPrn-0 Examples include N,N'-diphenyl-N,N'-bis(9-phenyl-9H-carbazole-2-yl)naphtho[2,3-b;6,7-b']bisbenzofuran-3,10-diamine (abbreviation: 3,10PCA2Nbf(IV)-02) and 3,10-bis[N-(dibenzofuran-3-yl)-N-phenylamino]naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3,10FrA2Nbf(IV)-02). In particular, pyrenediamine compounds such as 1,6FLPAPrn, 1,6mMemFLPAPrn, and 1,6BnfAPrn-03 can be used.

[0200] Also, 5,9-diphenyl-5H,9H-[1,4]benzazabolino[2,3,4-kl]phenazabolin (abbreviated as DABNA-1), 9-(biphenyl-3-yl)-N,N,5,11-tetraphenyl-5H,9H-[1,4]benzazabolino[2,3,4-kl]phenazabolin-3-amine (abbreviated as DABNA-2), 2,12-di(tert-butyl)-5,9-di(4-tert-butylphenyl)-N,N-di Phenyl-5H,9H-[1,4]benzazabolino[2,3,4-kl]phenazabolin-7-amine (abbreviation: DPhA-tBu4DABNA), 2,12-di(tert-butyl)-N,N,5,9-tetra(4-tert-butylphenyl)-5H,9H-[1,4]benzazabolino[2,3,4-kl]phenazabolin-7-amine (abbreviation: tBuDPhA-tBu4DABNA), 2,12-di(tert-butyl)- 5,9-di(4-tert-butylphenyl)-7-methyl-5H,9H-[1,4]benzazabolino[2,3,4-kl]phenazabolin (abbreviation: Me-tBu4DABNA), N7,N7,N13,N13,5,9,11,15-octaphenyl-5H,9H,11H,15H-[1,4]benzazabolino[2,3,4-kl][1,4]benzazabolino[4',3',2':4,5][1,4]benzazabolino[3, Condensed heteroaromatic compounds containing nitrogen and boron, such as 2-b]phenazavolin-7,13-diamine (abbreviated as ν-DABNA) and 2-(4-tert-butylphenyl)benz[5,6]indro[3,2,1-jk]benzo[b]carbazole (abbreviated as tBuPBibc), particularly compounds having a diaza-boranaphtho-anthracene skeleton, can be suitably used because they produce blue emission with a narrow emission spectrum and good color purity.

[0201] In addition to these, there is 9,10,11-tris[3,6-bis(1,1-dimethylethyl)-9H-carbazolyl-9-yl]-2,5,15,18-tetrakis(1,1-dimethylethyl)indoro[3,2,1-de]indoro[3',2',1':8,1][1,4]benzazavolino[2,3,4-kl]phenazavolin (abbreviation: BBCz-G), 9,11-bis[ Compounds having an indole skeleton, such as 3,6-bis(1,1-dimethylethyl)-9H-carbazolyl-9-yl]-2,5,15,18-tetrakis(1,1-dimethylethyl)indoro[3,2,1-de]indoro[3',2',1':8,1][1,4]benzazavolino[2,3,4-kl]phenazavolin (abbreviation: BBCz-Y), can be suitably used.

[0202] <<Luminescent material that converts triplet excitation energy into light emission>> Next, examples of luminescent materials that can be used in the luminescent layer 113 to convert triplet excitation energy into luminescence include phosphorescent materials (phosphorescent materials) or TADF materials that exhibit thermally activated delayed fluorescence.

[0203] A phosphorescent material is a compound that exhibits phosphorescence and does not fluoresce at any temperature range above low temperatures (e.g., 77K) and below room temperature (i.e., between 77K and 313K). The phosphorescent material preferably contains a metal element with strong spin-orbit interaction, and examples include organometallic complexes, metal complexes (platinum complexes), and rare earth metal complexes. Specifically, transition metal elements are preferred, and particularly platinum group elements (ruthenium (Ru), rhodium (Rh), palladium (Pd), osmium (Os), iridium (Ir), or platinum (Pt)) are preferred. The presence of iridium is especially preferable because it increases the transition probability involved in the direct transition between the singlet ground state and the triplet excited state.

[0204] ≪Phosphorescent materials (peak wavelength between 450nm and 570nm: blue or green)≫ Examples of phosphorescent materials that exhibit blue or green light and have a peak wavelength of emission spectrum between 450 nm and 570 nm include the following:

[0205] 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)-5-isopropyl-3-phenyl-4H-1,2,4-triazolato]iridium(III) (abbreviation: [Ir(iPrptz-3b)3]), Organometallic complexes having a 4H-triazole ring, such as tris[3-(5-biphenyl)-5-isopropyl-4-phenyl-4H-1,2,4-triazolato]iridium(III) (abbreviation: [Ir(iPr5btz)3]), tris[3-methyl-1-(2-methylphenyl)-5-phenyl-1H-1,2,4-triazolato]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 having a 1H-triazole ring, such as fac-tris[1-(2,6-diisopropylphenyl)-2-phenyl-1H-imidazole]iridium(III) (abbreviation: [Ir(iPrpim)3]), tris[3-(2,6-dimethylphenyl)-7-methylimidazo[1,2-f]phenantridinato]iridium(III) (abbreviation: [Ir(dmpimpt-Me)3]), tris(2-{1-[2,6-bis(1-methylethyl)phenyl]-1H-imidazole-2-yl-κN3}-4-cyanophenyl-κC)iridium Organometallic complexes having an imidazole ring, such as Ir(III) (abbreviation: CNImIr), organometallic complexes having a benzimidazolidene skeleton, such as tris[(6-tert-butyl-3-phenyl-2H-imidazo[4,5-b]pyrazine-1-yl-κC2)phenyl-κC]iridium(III) (abbreviation: [Ir(cb)3]), bis[2-(4',6'-difluorophenyl)pyridinato-N,C2']iridium(III)tetrakis(1-pyrazolyl)borate (abbreviation: FIr6), bis[2-(4',6'-difluorophenyl)pyridinato-N,C2'] Iridium(III) picolinate (abbreviation: Firpic), bis{2-[3',5'-bis(trifluoromethyl)phenyl]pyridinate-N,C, 2’ Iridium(III) picolinate (abbreviation: [Ir(CF3ppy)2(pic)]), bis[2-(4',6'-difluorophenyl)pyridinate-N,C 2’ Examples include organometallic complexes using phenylpyridine derivatives having electron-withdrawing groups as ligands, such as iridium(III) acetylacetonate (abbreviated as Fir(acac)), and platinum complexes such as (2-{3-[3-(3,5-di-tert-butylphenyl)benzimidazole-1-yl-2-ylidene-κC2]phenoxy-κC2}-9-(4-tert-butyl-2-pyridinyl-κN)carbazole-2,1-diyl-κC1)platinum(II) (abbreviated as PtON-TBBI). Compounds in which some of the hydrogen atoms in these compounds are replaced with deuterium can also be used.

[0206] ≪Phosphorescent materials (peak wavelength between 495nm and 590nm: green or yellow)≫ Examples of phosphorescent materials that exhibit a green or yellow color and have a peak wavelength of emission spectrum between 495 nm and 590 nm include the following:

[0207] For example, tris(4-methyl-6-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mppm)3]), tris(4-t-butyl-6-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(tBuppm)3]), (acetylacetonato)bis(6-methyl-4-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mppm)2(acac)]), (acetylacetonato)bis(6-tert- (Ir(tBuppm)2(acac)), (acetylacetonato)bis[6-(2-norbornyl)-4-phenylpyrimidinato]iridium(III) (abbreviation: [Ir(nbppm)2(acac)]), (acetylacetonato)bis[5-methyl-6-(2-methylphenyl)-4-phenylpyrimidinato]iridium(III) (abbreviation: [Ir(mpmppm Organometallic iridium(III) having a pyrimidine ring, such as (acetylacetonato)bis{4,6-dimethyl-2-[6-(2,6-dimethylphenyl)-4-pyrimidinyl-κN3]phenyl-κC}iridium(III) (abbreviation: [Ir(dmppm-dmp)2(acac)]), (acetylacetonato)bis(4,6-diphenylpyrimidinato)iridium(III) (abbreviation: [Ir(dppm)2(acac)]), iridium complexes having a pyrazine ring, such as (acetylacetonato)bis(3,5-dimethyl-2-phenylpyradinato)iridium(III) (abbreviation: [Ir(mppr-Me)2(acac)]), (acetylacetonato)bis(5-isopropyl-3-methyl-2-phenylpyradinato)iridium(III) (abbreviation: [Ir(mppr-iPr)2(acac)]), and tris(2-phenylpyridinato-N,C) 2’ Iridium(III) (abbreviation: [Ir(ppy)3]), bis(2-phenylpyridinate-N,C) 2’Iridium(III) acetylacetonate (abbreviation: [Ir(ppy)2(acac)]), bis(benzo[h]quinolinate)iridium(III) acetylacetonate (abbreviation: [Ir(bzq)2(acac)]), tris(benzo[h]quinolinate)iridium(III) (abbreviation: [Ir(bzq)3]), tris(2-phenylquinolinate-N,C) 2’ Iridium(III) (abbreviation: [Ir(pq)3]), bis(2-phenylquinolinato-N,C) 2’Iridium(III) acetylacetonate (abbreviation: [Ir(pq)2(acac)]), bis[2-(2-pyridinyl-κN)phenyl-κC][2-(4-phenyl-2-pyridinyl-κN)phenyl-κC] Iridium(III) (abbreviation: [Ir(ppy)2(4dppy)]), bis[2-(2-pyridinyl-κN)phenyl-κC][2-(4-methyl-5-phenyl-2-pyridinyl-κN)phenyl-κC], [2-d3-methyl-8-(2-pyridinyl-κN)benzofl[2,3-b]pyridine-κC] bis[2-(5-d3-methyl [2-pyridinyl-κN2)phenyl-κC]iridium(III) (abbreviation: Ir(5mppy-d3)2(mbfpypy-d3)), {2-(methyl-d3)-8-[4-(1-methylethyl-1-d)-2-pyridinyl-κN]benzofl[2,3-b]pyridin-7-yl-κC}bis{5-(methyl-d3)-2-[5-(methyl-d3)-2-pyridinyl-κN]phenyl-κC}iridium(III) (abbreviation: Ir(5mppy-d6)2(mbfpypy-iPr-d4)), [2-(methyl-d3)-8-(2-pyridinyl-κN)ben [zoflo[2,3-b]pyridine-κC]bis[2-(2-pyridinyl-κN)phenyl-κC]iridium(III) (abbreviation: Ir(ppy)2(mbfpypy-d3)), [2-(4-methyl-5-phenyl-2-pyridinyl-κN)phenyl-κC]bis[2-(2-pyridinyl-κN)phenyl-κC]iridium(III) (abbreviation: Ir(ppy)2(mdppy)), [2-(4-d3-methyl-5-phenyl-2-pyridinyl-κN2)phenyl-κC]bis[2-(5-d3-methyl-2-pyridinyl-κN2)phenyl-κC]iridium iridium organometallic complexes having a pyridine ring, such as Iridium(III) (abbreviation: [Ir(5mppy-d3)2(mdppy-d3)]), [2-methyl-8-(2-pyridinyl-κN)benzofloflo[2,3-b]pyridine-κC]bis[2-(2-pyridinyl-κN)phenyl-κC]iridium(III) (abbreviation: Ir(ppy)2(mbfpypy)), and Tris{2-[5-(methyl-d3)-4-phenyl-2-pyridinyl-κN]phenyl-κC}iridium(III) (abbreviation: Ir(5m4dppy-d3)3), bis(2,4-diphenyl-1,3-Oxazolato-N,C, 2’ Iridium(III) acetylacetonate (abbreviation: [Ir(dpo)2(acac)]), bis{2-[4'-(perfluorophenyl)phenyl]pyridinate-N,C 2’ Iridium(III) acetylacetonate (abbreviation: [Ir(p-PF-ph)2(acac)]), bis(2-phenylbenzothiazolat-N,C) 2’ )Organometallic complexes such as iridium(III) acetylacetonate (abbreviation: [Ir(bt)2(acac)]), (2-{1-(5-tert-butylbiphenyl-2-yl)-4-[3-tert-butyl-5-(4-phenyl-2-pyridinyl-κN)phenyl-κC6]-2-benzimidazolyl-κN3}-4,6-di-tert-butylphenolate-κO)platinum(II) (abbreviation: Pt(tBudppymmtBubiz-tBubp)), [2-(4-(3,5-di-tert- Examples include organometallic platinum complexes such as butylphenyl)-6-{3-[4-(5'-tert-butyl[1,1':3',1''-terphenyl]-2'-yl)-2-pyridinyl-κN]phenyl-κC2}-2-pyridinyl-κN)phenolate-κO]platinum(II) (abbreviation: Pt(4tButpppypyp-mmtBup)) and rare earth metal complexes such as tris(acetylacetonato)(monophenanthroline)terbium(III) (abbreviation: [Tb(acac)3(Phen)]). Compounds in which some of the hydrogen atoms in these compounds are replaced with deuterium can also be used.

[0208] ≪Phosphorescent materials (peak wavelength between 570nm and 750nm: yellow or red)≫ Examples of phosphorescent materials that exhibit a yellow or red color and have a peak wavelength of emission spectrum between 570 nm and 750 nm include the following:

[0209] For example, (diisobutyrylmethanato)bis[4,6-bis(3-methylphenyl)pyrimidinato]iridium(III) (abbreviation: [Ir(5mdppm)2(dibm)]), bis[4,6-bis(3-methylphenyl)pyrimidinato](dipivaloylmethanato)iridium(III) (abbreviation: [Ir(5mdppm)2(dpm)]), (dipivaloylmethanato)bis[4,6-di(naphthalene-1-yl)pyrimidinato]iridium(III) (abbreviation: [Ir(d1npm)2(dpm)]), and other pyramidal compounds. Organometallic complexes having a limidine ring: (acetylacetonato)bis(2,3,5-triphenylpyrazinato)iridium(III) (abbreviation: [Ir(tppr)2(acac)]), bis(2,3,5-triphenylpyrazinato)(dipivaloylmethanato)iridium(III) (abbreviation: [Ir(tppr)2(dpm)]), bis{4,6-dimethyl-2-[3-(3,5-dimethylphenyl)-5-phenyl-2-pyrazinyl-κN]phenyl-κC}(2,6-dimethyl-3,5-heptanedionato-κ 2 O,O') Iridium(III) (abbreviation: [Ir(dmdppr-P)2(dibm)]), bis{4,6-dimethyl-2-[5-(4-cyano-2,6-dimethylphenyl)-3-(3,5-dimethylphenyl)-2-pyradinyl-κN]phenyl-κC}(2,2,6,6-tetramethyl-3,5-heptanedionato-κ 2 O,O') Iridium(III) (abbreviation: [Ir(dmdppr-dmCP)2(dpm)]), bis{2-[5-(2,6-dimethylphenyl)-3-(3,5-dimethylphenyl)-2-pyrazinyl-κN]-4,6-dimethylphenyl-κC}(2,2',6,6'-tetramethyl-3,5-heptanedionato-κ 2 O,O') Iridium(III) (abbreviation: [Ir(dmdppr-dmp)2(dpm)]), (acetylacetonato)bis(2-methyl-3-phenylquinoxalinato-N,C 2’ Iridium(III) (abbreviation: [Ir(mpq)2(acac)]), (acetylacetonato)bis(2,3-diphenylquinoxalinato-N,C) 2’Organometallic complexes having a pyrazine ring, such as iridium(III) (abbreviation: [Ir(dpq)2(acac)]), (acetylacetonato)bis[2,3-bis(4-fluorophenyl)quinoxalinato]iridium(III) (abbreviation: [Ir(Fdpq)2(acac)]), and tris(1-phenylisoquinolinato-N,C) 2’ Iridium(III) (abbreviation: [Ir(piq)3]), bis(1-phenylisoquinolinato-N,C) 2’ Iridium(III) acetylacetonate (abbreviation: [Ir(piq)2(acac)]), and bis[4,6-dimethyl-2-(2-quinolinyl-κN)phenyl-κC](2,4-pentanedionato-κ 2 Organometallic complexes having a pyridine ring, such as (3,7-diethyl-4,6-nonanedionato-κO4,κO6)bis[2,4-dimethyl-6-[7-(1-methylethyl)-1-isoquinolinyl-κN]phenyl-κC]iridium(III), and (3,7-diethyl-4,6-nonanedionato-κO4,κO6)bis[2,4-dimethyl-6-[5-(1-methylethyl)-2-quinolinyl-κN]phenyl-κC]iridium(III). Examples include platinum complexes such as 3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrin platinum(II) (abbreviated as [PtOEP]), tris(1,3-diphenyl-1,3-propanedionato)(monophenanthroline)europium(III) (abbreviated as [Eu(DBM)3(Phen)]), and rare earth metal complexes such as tris[1-(2-tenoyl)-3,3,3-trifluoroacetonato](monophenanthroline)europium(III) (abbreviated as [Eu(TTA)3(Phen)]). Compounds in which some of the hydrogen atoms in these compounds are replaced with deuterium can also be used.

[0210] ≪TADF material≫ Furthermore, the following materials can be used as TADF materials. A TADF material is a material in which the energy difference between the S1 level and the T1 level is small (preferably 0.20 eV or less), the triplet excited state can be upconverted to the singlet excited state with a small amount of thermal energy (reverse intersystem crossing), and the emission (fluorescence) from the singlet excited state is efficiently observed. Conditions for efficiently obtaining thermally activated delayed fluorescence include an energy difference between the triplet excited energy level and the singlet excited energy level of 0.00 eV or more and 0.20 eV or less, preferably 0.00 eV or more and 0.10 eV or less. In addition, delayed fluorescence in TADF materials refers to emission that has a spectrum similar to normal fluorescence but with a remarkably long lifetime. Its lifetime is 1 × 10⁻⁶ -6 More than a second, or 1 x 10⁻⁶ -3 It is more than a second.

[0211] Furthermore, TADF materials can also be used as electron transport materials, hole transport materials, and host materials.

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

[0213] [ka]

[0214] Other examples include 2-(biphenyl-4-yl)-4,6-bis(12-phenylindoro[2,3-a]carbazol-11-yl)-1,3,5-triazine (abbreviated as PIC-TRZ), 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol-9-yl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviated as PCCzPTzn), and 2-[4-(10H-phenoxa [Zin-10-yl)phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviation: PXZ-TRZ), 3-[4-(5-phenyl-5,10-dihydrophenazin-10-yl)phenyl]-4,5-diphenyl-1,2,4-triazole (abbreviation: PPZ-3TPT), 3-(9,9-dimethyl-9H-acridine-10-yl)-9H-xanthene-9-one (abbreviation: ACRXTN), bis[4-(9,9- Dimethyl-9,10-dihydroacridine)phenyl]sulfone (abbreviation: DMAC-DPS), 10-phenyl-10H,10'H-spiro[acridine-9,9'-anthracene]-10'-one (abbreviation: ACRSA), 4-(9'-phenyl-[3,3'-bi-9H-carbazole]-9-yl)benzofloflo[3,2-d]pyrimidine (abbreviation: 4PCCzBfpm), 4-[4-(9'-phenyl-[3,3'- You may also use heteroaromatic compounds that have π-electron-rich heteroaromatic compounds and π-electron-deficient heteroaromatic compounds such as bi-9H-carbazole]-9-yl)phenyl]benzofl[3,2-d]pyrimidine (abbreviation: 4PCCzPBfpm) and 9-[3-(4,6-diphenyl-1,3,5-triazine-2-yl)phenyl]-9'-phenyl-2,3'-bi-9H-carbazole (abbreviation: mPCCzPTzn-02).

[0215] Furthermore, a material in which a π-electron-rich heteroaromatic compound and a π-electron-deficient heteroaromatic compound are directly bonded is particularly preferable because both the donor properties of the π-electron-rich heteroaromatic compound and the acceptor properties of the π-electron-deficient heteroaromatic compound become stronger, and the energy difference between the singlet excited state and the triplet excited state becomes smaller. In addition, a TADF material (TADF100) in which the singlet excited state and the triplet excited state are in thermal equilibrium may be used as the TADF material. Since such a TADF material has a shorter luminescence lifetime (excitation lifetime), it is possible to suppress the decrease in efficiency in the high-brightness region of the light-emitting device.

[0216] [ka]

[0217] In addition to the above, other materials that have the function of converting triplet excitation energy into light emission include nanostructures of transition metal compounds having a perovskite structure. Nanostructures of metal halogen perovskites are particularly desirable. Nanoparticles and nanorods are preferred as such nanostructures.

[0218] In the light-emitting layers (113, 113a, 113b), the organic compounds (host materials, etc.) used in combination with the light-emitting material (guest material) described above may be one or more materials having an energy gap larger than the energy gap of the light-emitting material (guest material).

[0219] ≪Host materials for fluorescence emission≫ When the light-emitting material used in the light-emitting layer (113, 113a, 113b) is a fluorescent light-emitting material, it is preferable to use an organic compound (host material) that has a high singlet excited state energy level and a low triplet excited state energy level, or an organic compound with a high fluorescence quantum yield. Therefore, any organic compound that satisfies these conditions can be used, such as the hole transport material (described above) and electron transport material (described below) shown in this embodiment. In addition, organic compounds having a trisubstituted silyl group as described in Embodiment 1 and this embodiment can be used.

[0220] Although some of these overlap with the specific examples mentioned above, from the perspective of preferred combinations with luminescent substances (fluorescent substances), examples of organic compounds (host materials) include condensed polycyclic aromatic compounds such as anthracene derivatives, tetracene derivatives, phenanthrene derivatives, pyrene derivatives, chrysene derivatives, and dibenzo[g,p]chrysene derivatives.

[0221] Specific examples of organic compounds (host materials) that are preferable to use in combination with fluorescent luminescent substances include 9-phenyl-3-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviated as PCzPA), 3,6-diphenyl-9-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviated as DPCzPA), PCPN, 9,10-diphenylanthracene (abbreviated as DPAnth), and N,N-diphenyl-9-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole. Bazole-3-amine (abbreviation: CzA1PA), 4-(10-phenyl-9-anthryl)triphenylamine (abbreviation: DPhPA), YGAPA, PCAPA, N,9-diphenyl-N-{4-[4-(10-phenyl-9-anthryl)phenyl]phenyl}-9H-carbazole-3-amine (abbreviation: PCAPBA), N-(9,10-diphenyl-2-anthryl)-N,9-diphenyl-9H-carbazole-3-amine (abbreviation: 2PCAPA), 6,12-dimethoxy-5,11-diphenylchrysene, N,N,N ',N',N'',N'',N''',N'''-Octaphenyldibenzo[g,p]chrysene-2,7,10,15-tetraamine (abbreviation: DBC1), 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)bife [Nyl-4-yl]anthracene (abbreviated as FLPPA), 9,10-bis(3,5-diphenylphenyl)anthracene (abbreviated as DPPA), 9,10-di(2-naphthyl)anthracene (abbreviated as DNA), 2-tert-butyl-9,10-di(2-naphthyl)anthracene (abbreviated as t-BuDNA), 9-(1-naphthyl)-10-(2-naphthyl)anthracene (abbreviated as α,β-ADN), 2-(10-phenylanthracene-9-yl)dibenzofuran, 2-(10-phenyl-9-anthryl)benzo[b]naphtho[2,3-d]furan (abbreviation: Bnf(II)PhA), 9-(1-naphthyl)-10-[4-(2-naphthyl)phenyl]anthracene (abbreviation: αN-βNPAnth), 2,9-di(1-naphthyl)-10-phenylanthracene (abbreviation: 2αN-αNPhA), 9-(1-naphthyl)-10-[3-(1-naphthyl)phenyl]anthracene (abbreviation: αN-mαNPAnth) , 9-(2-naphthyl)-10-[3-(1-naphthyl)phenyl]anthracene (abbreviation: βN-mαNPAnth), 9-(1-naphthyl)-10-[4-(1-naphthyl)phenyl]anthracene (abbreviation: αN-αNPAnth), 9-(2-naphthyl)-10-[4-(2-naphthyl)phenyl]anthracene (abbreviation: βN-βNPAnth), 2-(1-naphthyl)-9 -(2-naphthyl)-10-phenylanthracene (abbreviation: 2αN-βNPhA), 9-(2-naphthyl)-10-[3-(2-naphthyl)phenyl]anthracene (abbreviation: βN-mβNPAnth), 1-{4-[10-(biphenyl-4-yl)-9-anthryl]phenyl}-2-ethyl-1H-benzimidazole (abbreviation: EtBImPBPhA), 9,9'-bianthryl Examples include lyl (abbreviated as BANT), 9,9'-(stilbene-3,3'-diyl)diphenanthrene (abbreviated as DPNS), 9,9'-(stilbene-4,4'-diyl)diphenanthrene (abbreviated as DPNS2), 1,3,5-tri(1-pyrenyl)benzene (abbreviated as TPB3), 5,12-diphenyltetracene, and 5,12-bis(biphenyl-2-yl)tetracene.

[0222] ≪Host materials for phosphorescence≫ Furthermore, if the luminescent material used in the luminescent layers (113, 113a, 113b) is a phosphorescent material, then an organic compound (host material) with a triplet excitation energy greater than the triplet excitation energy of the luminescent material (the energy difference between the ground state and the triplet excited state) should be selected. When using multiple organic compounds (for example, a first host material and a second host material (or assist material), etc.) in combination with the luminescent material to form an excited complex, it is preferable to mix these multiple organic compounds with the phosphorescent material. Additionally, organic compounds having a trisubstituted silyl group, as described in Embodiment 1 and this embodiment, can be used.

[0223] This configuration allows for efficient emission using ExTET (Exciplex-Triplet Energy Transfer), which is energy transfer from the excited complex to the luminescent material. The combination of organic compounds should ideally be one that readily forms an excited complex, and a combination of a compound that readily accepts holes (hole transport material) and a compound that readily accepts electrons (electron transport material) is particularly preferable.

[0224] In addition, although some of these overlap with the specific examples mentioned above, from the perspective of preferred combinations with luminescent substances (phosphorescent substances), suitable organic compounds (host materials, assist materials) include aromatic amines (organic compounds having an aromatic amine skeleton), carbazole derivatives (organic compounds having a carbazole ring), dibenzothiophene derivatives (organic compounds having a dibenzothiophene ring), dibenzofuran derivatives (organic compounds having a dibenzofuran ring), oxadiazole derivatives (organic compounds having an oxadiazole ring), triazole derivatives (organic compounds having a triazole ring), and benzimidazole derivatives (benzo- Examples include organic compounds having a midazole ring, quinoxaline derivatives (organic compounds having a quinoxaline ring), dibenzoquinoxaline derivatives (organic compounds having a dibenzoquinoxaline ring), pyrimidine derivatives (organic compounds having a pyrimidine ring), triazine derivatives (organic compounds having a triazine ring), pyridine derivatives (organic compounds having a pyridine ring), bipyridine derivatives (organic compounds having a bipyridine ring), phenanthroline derivatives (organic compounds having a phenanthroline ring), phlodiazine derivatives (organic compounds having a phlodiazine ring), zinc and aluminum-based metal complexes, etc.

[0225] Furthermore, among the above-mentioned organic compounds, specific examples of aromatic amines and carbazole derivatives, which are organic compounds with high hole transport properties, are the same as the specific examples of hole transport materials described above, and all of these are preferred as host materials.

[0226] Furthermore, among the above organic compounds, specific examples of dibenzothiophene derivatives and dibenzofuran derivatives that exhibit high hole transport properties include mmDBFFLBi-II, DBF3P-II, DBT3P-II, DBTFLP-III, DBTFLP-IV, and 4-[3-(triphenylene-2-yl)phenyl]dibenzothiophene (abbreviated as mDBTPTp-II), all of which are preferred as host materials.

[0227] Other preferred host materials include metal complexes having oxazole-based or thiazole ligands such as bis[2-(2-benzoxazolyl)phenolate]zinc(II) (abbreviated as ZnPBO) and bis[2-(2-benzothiazolyl)phenolate]zinc(II) (abbreviated as ZnBTZ).

[0228] Furthermore, among the above organic compounds, specific examples of organic compounds with high electron transport properties, such as oxadiazole derivatives, triazole derivatives, benzimidazole derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, quinazoline derivatives, and phenanthroline derivatives, include 2-(4-biphenylyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazole-2-yl]benzene (abbreviation: OXD-7), 9-[4-(5-phenyl-1,3,4-oxadiazole-2-yl)phenyl]-9H-carbazole (abbreviation: CO11), 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (abbreviation: TAZ), 2,2',2''-(1,3,5-benzenetriyl)tris(1-phenyl-1H-benzoimidazole) (abbreviation: TPBI), 2-[3-(dibenzothiophen-4-yl)phenyl]-1-phenyl-1H-benzoimidazole (abbreviation: mDBTBIm-II) Organic compounds containing heteroaromatic rings with an azole ring, such as 4,4'-bis(5-methylbenzoxazole-2-yl)stilbene (abbreviation: BzOs), and heteroaromatic rings containing a phenanthroline ring, such as vasophenanthroline (abbreviation: BPhen), vasocuproin (abbreviation: BCP), 2,9-di(naphthalene-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBPhen), and 2,2'-(1,3-phenylene)bis(9-phenyl-1,10-phenanthroline) (abbreviation: mPPhen2P). Organic compounds, 2-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTPDBq-II), 2-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II), 2-[3'-(9H-carbazole-9-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mCzBPDBq), 2-[4-(3,6-diphenyl-9H-carbazole-9-yl)phenyl]dibenzo[f,Examples include organic compounds containing heteroaromatic rings having a dibenzoquinoxaline ring, such as [h]quinoxaline (abbreviation: 2CzPDBq-III), 7-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 7mDBTPDBq-II), and 6-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 6mDBTPDBq-II), 2-{4-[9,10-di(2-naphthyl)-2-anthryl]phenyl}-1-phenyl-1H-benzimidazole (abbreviation: ZADN), and 2-[4'-(9-phenyl-9H-carbazole-3-yl)-3,1'-biphenyl-1-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mpPCBPDBq), all of which are preferred as host materials. ,

[0229] Furthermore, among the above organic compounds, specific examples of organic compounds with high electron transport capabilities include pyridine derivatives, diazine derivatives (including pyrimidine derivatives, pyrazine derivatives, and pyridazine derivatives), triazine derivatives, and phlodiazine derivatives, such as 4,6-bis[3-(phenanthrene-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm), 4,6-bis[3-(dibenzothiophen-4-yl)phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-II), and 4,6-bis[3-(9H-carbazole-9-yl)phenyl]pyrimidine (abbreviation: Names: 4,6mCzP2Pm), PCCzPTzn, mPCCzPTzn-02, 3,5-bis[3-(9H-carbazole-9-yl)phenyl]pyridine (abbreviation: 35DCzPPy), 1,3,5-tri[3-(3-pyridyl)phenyl]benzene (abbreviation: TmPyPB), 9,9'-[pyrimidine-4,6-diylbis(biphenyl-3,3'-diyl)]bis(9H-carbazole) (abbreviation: 4,6mCzBP2Pm), 2-[3'-(9,9-dimethyl-9H-fluoren-2-yl)biphenyl-3-yl]-4,6-diphenyl-1 ,3,5-triazine (abbreviation: mFBPTzn), 8-(biphenyl-4-yl)-4-[3-(dibenzothiophen-4-yl)phenyl]-[1]benzoflo[3,2-d]pyrimidine (abbreviation: 8BP-4mDBtPBfpm), 9-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]naphtho[1',2':4,5]flo[2,3-b]pyrazine (abbreviation: 9mDBtBPNfpr), 9-[3'-(dibenzothiophen-4-yl)biphenyl-4-yl]naphtho[1',2':4,5]flo[2,3-b]pyrazine (abbreviation :9pmDBtBPNfpr), 11-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]phenanthro[9',10':4,5]flo[2,3-b]pyrazine (abbreviation: 11mDBtBPPnfpr), 11-[3'-(dibenzothiophen-4-yl)biphenyl-4-yl]phenanthro[9',10':4,5]flo[2,3-b]pyrazine, 11-[(3'-9H-carbazole-9-yl)biphenyl-3-yl]phenanthro[9',10':4,5]flo[2,3-b]pyrazine, 12-(9'-phenyl-[3,3'-bi-9H-carbazole]-9-yl)phenanthro[9',10':4,5]flo[2,3-b]pyrazine (abbreviation: 12PCCzPnfpr), 9-[3'-(9-phenyl-9H-carbazole-3-yl)biphenyl-4-yl]naphtho[1',2':4,5]flo[2,3-b]pyrazine (abbreviation: 9pmPCBPNfpr), 9-(9'-phenyl-[3,3'-bi-9H-carbazole]-9-yl)naphtho[1',2':4,5]flo[2,3-b]pyrazine (abbreviation: 9PCCzNfpr), 10-(9'-phenyl-[3,3'- Bi-9H-carbazole]-9-yl)naphtho[1',2':4,5]flo[2,3-b]pyrazine (abbreviation: 10PCCzNfpr), 9-[3'-(6-phenylbenzo[b]naphtho[1,2-d]furan-8-yl)biphenyl-3-yl]naphtho[1',2':4,5]flo[2,3-b]pyrazine (abbreviation: 9mBnfBPNfpr), 9-{3-[6-(9,9-dimethylfluoren-2-yl)dibenzothiophen-4-yl]phenyl}naphtho[1',2':4,5]flo[2,3-b]pyrazine (abbreviation: 9mFDBtPNfpr), 9-[ 3'-(6-phenyldibenzothiophen-4-yl)biphenyl-3-yl]naphtho[1',2':4,5]flo[2,3-b]pyrazine (abbreviation: 9mDBtBPNfpr-02), 9-[3-(9'-phenyl-[3,3'-bi-9H-carbazole]-9-yl)phenyl]naphtho[1',2':4,5]flo[2,3-b]pyrazine (abbreviation: 9mPCCzPNfpr), 9-[3'-(2,8-diphenyldibenzothiophen-4-yl)biphenyl-3-yl]naphtho[1',2':4,5]flo[2,3-b]pyrazine, 11-[3'-(2 ,8-diphenyldibenzothiophen-4-yl)biphenyl-3-yl]phenanthro[9',10':4,5]flo[2,3-b]pyrazine, 5-[3-(4,6-diphenyl-1,3,5-triazine-2-yl)phenyl]-7,7-dimethyl-5H,7H-indeno[2,1-b]carbazole (abbreviation: mINc(II)PTzn), 2-[3'-(triphenylene-2-yl)biphenyl-3-yl]-4,6-diphenyl-1,3,5-triazine (abbreviation: mTpBPTzn), 2-(biphenyl-4-yl)-4-phenyl-6-(9,9'-Spirobi[9H-Fluorene]-2-yl)-1,3,5-triazine (abbreviation: BP-SFTzn), 2,6-Bis(4-naphthalene-1-ylphenyl)-4-[4-(3-pyridyl)phenyl]pyrimidine (abbreviation: 2,4NP-6PyPPm), 3-[9-(4,6-diphenyl-1,3,5-triazine-2-yl)-2-dibenzofuranyl]-9-phenyl-9H-carbazole (abbreviation: PCDBfTzn), 2-(biphenyl-3-yl)-4-phenyl-6-[8-([1,1':4',1''-terphenyl]-4-yl) Examples include organic compounds containing heteroaromatic rings having a diazine ring, such as -1-dibenzofuranyl]-1,3,5-triazine (abbreviation: mBP-TPDBfTzn), 6-(biphenyl-3-yl)-4-[3,5-bis(9H-carbazole-9-yl)phenyl]-2-phenylpyrimidine (abbreviation: 6mBP-4Cz2PPm), and 4-[3,5-bis(9H-carbazole-9-yl)phenyl]-2-phenyl-6-(biphenyl-4-yl)pyrimidine (abbreviation: 6BP-4Cz2PPm), all of which are preferred as host materials.

[0230] Furthermore, among the above organic compounds, specific examples of metal complexes that are organic compounds with high electron transport properties include zinc-based or aluminum-based metal complexes such as tris(8-quinolinolato)aluminum(III) (abbreviated as Alq3), tris(4-methyl-8-quinolinolato)aluminum(III) (abbreviated as Almq3), bis(10-hydroxybenzo[h]quinolinato)beryllium(II) (abbreviated as BeBq2), bis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum(III) (abbreviated as BAlq), bis(8-quinolinolato)zinc(II) (abbreviated as Znq), and metal complexes having a quinoline ring or a benzoquinoline ring, all of which are preferred as host materials.

[0231] Other polymer compounds such as poly(2,5-pyridinediyl) (abbreviated as PPy), poly[(9,9-dihexylfluorene-2,7-diyl)-co-(pyridine-3,5-diyl)] (abbreviated as PF-Py), and poly[(9,9-dioctylfluorene-2,7-diyl)-co-(2,2'-bipyridine-6,6'-diyl)] (abbreviated as PF-BPy) are also preferred as host materials.

[0232] Furthermore, organic compounds having a diazine ring, such as bipolar 9-phenyl-9'-(4-phenyl-2-quinazolinyl)-3,3'-bi-9H-carbazole (abbreviated as PCCzQz), 2mpPCBPDBq, mINc(II)PTzn, 11-[4-(biphenyl-4-yl)-6-phenyl-1,3,5-triazine-2-yl]-11,12-dihydro-12-phenyl-indoro[2,3-a]carbazole (abbreviated as BP-Icz(II)Tzn), and 7-[4-(9-phenyl-9H-carbazole-2-yl)quinazolin-2-yl]-7H-dibenzo[c,g]carbazole (abbreviated as PC-cgDBCzQz), which are organic compounds with high hole transport and electron transport properties, can also be used as host materials.

[0233] <Electron transport layer> The electron transport layers (114, 114a, 114b) are layers that transport electrons injected from the second electrode 102 and the charge generation layers (106, 106a, 106b) by the electron injection layers (115, 115a, 115b), described later, to the light-emitting layers (113, 113a, 113b). In one embodiment of the present invention, the light-emitting device can improve heat resistance by having a laminated structure for the electron transport layers. Furthermore, the electron-transporting material used in the electron transport layers (114, 114a, 114b) has an electron mobility of 1 × 10⁻¹⁰ at a square root of 600 electric field strength [V / cm]. -6 cm 2A material having an electron mobility of / Vs or higher is preferred. However, any material with higher electron transport capabilities than hole transport can be used. Furthermore, the electron transport layer (114, 114a, 114b) can function as a single layer, but it may also be a laminated structure of two or more layers. Since the above mixed material has heat resistance, performing the photolithography process on an electron transport layer using this material can suppress the influence of the thermal process on the device characteristics.

[0234] ≪Electron transport material≫ As electron-transporting materials that can be used in the electron transport layers (114, 114a, 114b), organic compounds with high electron transport properties can be used, for example, heteroaromatic compounds. A heteroaromatic compound is a cyclic compound that contains at least two different elements in its ring. The ring structure can include 3-membered rings, 4-membered rings, 5-membered rings, 6-membered rings, etc., but 5-membered rings or 6-membered rings are particularly preferred, and heteroaromatic compounds containing one or more of the elements of carbon, nitrogen, oxygen, or sulfur are preferred. Nitrogen-containing heteroaromatic compounds (nitrogen-containing heteroaromatic compounds) are particularly preferred, and it is preferable to use materials with high electron transport properties (electron-transporting materials) such as nitrogen-containing heteroaromatic compounds or π-electron-deficient heteroaromatic compounds containing them. In addition, organic compounds having a trisubstituted silyl group as described in Embodiment 1 and this embodiment can be used.

[0235] Furthermore, the electron transport material can be different from the material used for the light-emitting layer. Not all excitons generated by carrier recombination in the light-emitting layer can contribute to light emission; some may diffuse into layers adjacent to or near the light-emitting layer. To avoid this phenomenon, it is preferable that the energy level (lowest singlet excitation energy level or lowest triplet excitation energy level) of the material used in the layers adjacent to or near the light-emitting layer is higher than that of the material used for the light-emitting layer. Therefore, by using a different electron transport material than the one used for the light-emitting layer, a highly efficient device can be obtained.

[0236] Heteroaromatic compounds are organic compounds that have at least one heteroaromatic ring.

[0237] Furthermore, a heteroaromatic ring contains one of the following: a pyridine ring, a diazine ring, a triazine ring, an azole ring, an oxazole ring, or a thiazole ring. Heteroaromatic rings containing a diazine ring include those containing a pyrimidine ring, a pyrazine ring, or a pyridazine ring. Heteroaromatic rings containing an azole ring include those containing an imidazole ring, a triazole ring, or an oxadiazole ring.

[0238] Furthermore, heteroaromatic rings include fused heteroaromatic rings having a fused ring structure. Examples of fused heteroaromatic rings include quinoline rings, benzoquinoline rings, quinoxaline rings, dibenzoquinoxaline rings, quinazoline rings, benzoquinazoline rings, dibenzoquinazoline rings, phenanthroline rings, phlodiazine rings, and benzimidazole rings.

[0239] For example, among heteroaromatic compounds containing one or more of nitrogen, oxygen, or sulfur in addition to carbon, heteroaromatic compounds having a five-membered ring structure include heteroaromatic compounds having an imidazole ring, heteroaromatic compounds having a triazole ring, heteroaromatic compounds having an oxazole ring, heteroaromatic compounds having an oxadiazole ring, heteroaromatic compounds having a thiazole ring, and heteroaromatic compounds having a benzimidazole ring.

[0240] Furthermore, among heteroaromatic compounds that contain one or more elements other than carbon, such as nitrogen, oxygen, or sulfur, examples of heteroaromatic compounds having a six-membered ring structure include heteroaromatic compounds having heteroaromatic rings such as pyridine rings, diazine rings (including pyrimidine rings, pyrazine rings, pyridazine rings, etc.), triazine rings, and azole rings. Note that while heteroaromatic compounds with a structure in which pyridine rings are linked, examples include heteroaromatic compounds having a bipyridine structure and heteroaromatic compounds having a terpyridine structure.

[0241] Furthermore, examples of heteroaromatic compounds having a fused ring structure that partially includes the above-mentioned six-membered ring structure include heteroaromatic compounds having fused heteroaromatic rings such as quinoline rings, benzoquinoline rings, quinoxaline rings, dibenzoquinoxaline rings, phenanthroline rings, phlodiazine rings (including structures in which an aromatic ring is fused to the furan ring of a phlodiazine ring), and benzimidazole rings.

[0242] Specific examples of heteroaromatic compounds having the above-mentioned five-membered ring structure (azole ring (including imidazole ring, triazole ring, oxadiazole ring), oxazole ring, thiazole ring, benzimidazole ring, etc.) include PBD, OXD-7, CO11, TAZ, 3-(4-tert-butylphenyl)-4-(4-ethylphenyl)-5-(4-biphenylyl)-1,2,4-triazole (abbreviation: p-EtTAZ), TPBI, mDBTBIm-II, and BzOs.

[0243] Specific examples of heteroaromatic compounds having the above-mentioned 6-membered ring structure (including heteroaromatic rings having pyridine rings, diazine rings, triazine rings, etc.) include heteroaromatic compounds containing a pyridine ring such as 35DCzPPy, TmPyPB, PCCzPTzn, mPCCzPTzn-02, mINc(II)PTzn, mTpBPTzn, BP-SFTzn, 2,4NP-6PyPPm, PCDBfTzn, mBP-TPDBfTzn, and 2-{3-[3-(dibenzothiophene Heteroaromatic compounds containing a triazine ring, such as 4,6mPnP2Pm, 4,6mDBTP2Pm-II, 4,6mCzP2Pm, 4,6mCzBP2Pm, 6mBP-4Cz2PPm, 6BP-4Cz2PPm, and 4-[3-(dibenzothiophen-4-yl)phenyl]-8-(naphthalene-2-yl)-[1]ben Zoflo[3,2-d]pyrimidine (abbreviation: 8βN-4mDBtPBfpm), 8BP-4mDBtPBfpm, 9mDBtBPNfpr, 9pmDBtBPNfpr, 3,8-bis[3-(dibenzothiophen-4-yl)phenyl]benzoflo[2,3-b]pyrazine (abbreviation: 3,8mDBtP2Bfpr), 4,8-bis[3-(dibenzothiophen-4-yl)phenyl]-[1]benzoflo[3,2-d]pyrimidine (abbreviation: 4,8mDBtP2Bfpm), 8- Examples include heteroaromatic compounds containing a diazine (pyrimidine) ring, such as [3'-(dibenzothiophen-4-yl)biphenyl-3-yl]naphtho[1',2':4,5]flo[3,2-d]pyrimidine (abbreviated as 8mDBtBPNfpm) and 8-([2,2'-binaphthalene]-6-yl)-4-[3-(dibenzothiophen-4-yl)phenyl]-[1]benzoflo[3,2-d]pyrimidine (abbreviated as 8(βN2)-4mDBtPBfpm). Note that the above aromatic compounds containing a heteroaromatic ring include heteroaromatic compounds having a condensed heteroaromatic ring.

[0244] Other compound diazine (pyrimidine) ring compounds include 2,2'-(pyridine-2,6-diyl)bis(4-phenylbenzo[h]quinazoline) (abbreviation: 2,6(P-Bqn)2Py), 2,2'-([2,2'-bipyridine]-6,6'-diyl)bis(4-phenylbenzo[h]quinazoline) (abbreviation: 6,6'(P-Bqn)2BPy), 2,2'-(pyridine-2,6-diyl)bis{4-[4-(2-naphthyl)phenyl]-6-phenylpyrimidine} (abbreviation: 2,6(NP-PPm)2Py), 6mBP-4Cz2PPm, etc. Examples include heteroaromatic compounds containing a triazine ring, such as 2,4,6-tris[3'-(pyridin-3-yl)biphenyl-3-yl]-1,3,5-triazine (abbreviated as TmPPPyTz), 2,4,6-tris(2-pyridyl)-1,3,5-triazine (abbreviated as 2Py3Tzn), and 2-[3-(2,6-dimethyl-3-pyridinyl)-5-(9-phenanthryl)phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviated as mPn-mDMePyPTzn).

[0245] Specific examples of heteroaromatic compounds having a fused ring structure that partially includes a 6-membered ring structure (heteroaromatic compounds having a fused ring structure) include heteroaromatic compounds having a quinoxaline ring such as BPhen, BCP, NBPhen, mPPhen2P, 2,6(P-Bqn)2Py, 2mDBTPDBq-II, 2mDBTBPDBq-II, 2mCzBPDBq, 2CzPDBq-III, 7mDBTPDBq-II, 6mDBTPDBq-II, and 2mpPCBPDBq.

[0246] In addition to the heteroaromatic compounds shown above, the following metal complexes can be used in the electron transport layers (114, 114a, 114b). Examples include metal complexes having a quinoline ring or benzoquinoline ring such as Alq3, Almq3, 8-quinolinolatolithium (abbreviated as Liq), BAlq, and Znq, and metal complexes having an oxazole ring or thiazole ring such as ZnPBO and ZnBTZ.

[0247] Furthermore, polymer compounds such as PPy, PF-Py, and PF-BPy can also be used as electron transport materials.

[0248] Furthermore, the electron transport layers (114, 114a, 114b) may be not only single layers, but also have a structure in which two or more layers made of the above material are stacked.

[0249] <Electron injection layer> The electron injection layers (115, 115a, 115b) are layers containing a material with high electron injection capabilities. Furthermore, the electron injection layers (115, 115a, 115b) are layers for increasing the electron injection efficiency from the second electrode 102, and it is preferable to use a material in which the difference between the work function value of the material used for the second electrode 102 and the LUMO level value of the material used for the electron injection layers (115, 115a, 115b) is small (0.50 eV or less). Therefore, the electron injection layer 115 contains lithium, cesium, lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride (CaF2), 8-quinolinolatrium (abbreviated as Liq), 2-(2-pyridyl)phenolate (abbreviated as LiPP), 2-(2-pyridyl)-3-pyridinolatrium (abbreviated as LiPPy), 4-phenyl-2-(2-pyridyl)phenolate (abbreviated as LiPPP), and lithium oxide (LiO xAlkali metals such as cesium carbonate, alkaline earth metals, or compounds thereof can be used. Rare earth metals or rare earth metal compounds such as erbium fluoride (ErF3) and ytterbium (Yb) can also be used. In addition, 1-(9,9'-spirobi[9H-fluoren]-2-yl)-1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine (abbreviation: 2hppSF), 1,1'-(9,9'-spirobi[9H-fluoren]-2,7-diyl)bis(1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a] Compounds having a 1,3,4,6,7,8-tetrahydro-2H-pyrimido[1,2-a]pyrimidine skeleton can also be used, such as pyrimidine (abbreviated as 2,7hpp2SF) and 1,1'-pyridine-2,6-diyl-bis(1,3,4,6,7,8-hexahydro-2H-pyrimido[1,2-a]pyrimidine) (abbreviated as hpp2Py). The electron injection layers (115, 115a, 115b) may be formed by mixing multiple types of the above materials, or by stacking multiple types of the above materials. Furthermore, electrides may be used in the electron injection layers (115, 115a, 115b). Examples of electrides include substances obtained by adding a high concentration of electrons to a mixed oxide of calcium and aluminum. The materials that constitute the electron transport layers (114, 114a, 114b) described above can also be used.

[0250] Furthermore, a mixed material comprising an organic compound and an electron donor may be used in the electron injection layers (115, 115a, 115b). Such a mixed material exhibits excellent electron injection and electron transport properties because electrons are generated in the organic compound by the electron donor. In this case, the organic compound is preferably a material with excellent electron transport properties, and specifically, for example, electron transport materials (metal complexes and heteroaromatic compounds, etc.) used in the electron transport layers (114, 114a, 114b) described above can be used. As the electron donor, a substance that exhibits electron-donating properties to the organic compound can be used. Specifically, alkali metals, alkaline earth metals, and rare earth metals are preferred, such as lithium, cesium, magnesium, calcium, erbium, and ytterbium. Alkali metal oxides and alkaline earth metal oxides are also preferred, such as lithium oxide, calcium oxide, and barium oxide. Lewis bases such as magnesium oxide can also be used. Furthermore, organic compounds such as tetrathiafulvalene (abbreviated as TTF) can also be used. Furthermore, multiple layers of these materials may be used.

[0251] In addition, a mixed material consisting of an organic compound and a metal may be used for the electron injection layers (115, 115a, 115b). The organic compound used here preferably has a LUMO level of -3.60 eV or higher and -2.30 eV or lower. Furthermore, a material having lone pairs of electrons is preferred.

[0252] Therefore, as the organic compound used in the above-mentioned mixed material, a mixed material obtained by mixing a heteroaromatic compound with a metal, as described above for use in an electron transport layer, may be used. Preferred heteroaromatic compounds include materials having lone pairs of electrons, such as heteroaromatic compounds having a 5-membered ring structure (imidazole ring, triazole ring, oxazole ring, oxadiazole ring, thiazole ring, benzimidazole ring, etc.), heteroaromatic compounds having a 6-membered ring structure (pyridine ring, diazine ring (including pyrimidine ring, pyrazine ring, pyridazine ring, etc.), triazine ring, bipyridine ring, terpyridine ring, etc.), and heteroaromatic compounds having a fused ring structure that partially includes a 6-membered ring structure (quinoline ring, benzoquinoline ring, quinoxaline ring, dibenzoquinoxaline ring, phenanthroline ring, etc.). Specific materials have been described above, so further explanation is omitted here.

[0253] Furthermore, it is preferable to use transition metals belonging to Group 5, Group 7, Group 9, or Group 11 of the periodic table and materials belonging to Group 13 as the metals used in the above-mentioned mixed material, such as Ag, Cu, Al, or In. In this case, the organic compound forms a half-occupied orbital (SOMO) with the transition metal.

[0254] For example, when amplifying the light obtained from the light-emitting layer 113b, it is preferable to form the optical distance between the second electrode 102 and the light-emitting layer 113b to be less than 1 / 4 of the wavelength λ of the light emitted by the light-emitting layer 113b. In this case, this can be adjusted by changing the film thickness of the electron transport layer 114b or the electron injection layer 115b.

[0255] <Charge generation layer> The charge generation layer 106 has the function of injecting electrons into the EL layer 103a and holes into the EL layer 103b when a voltage is applied between the first electrode (anode) 101 and the second electrode (cathode) 102. The charge generation layer 106 may be a configuration in which an electron acceptor is added to a hole transport material (also called a P-type layer), or a configuration in which an electron donor is added to an electron transport material (also called an electron injection buffer layer). Furthermore, both of these configurations may be stacked. In addition, an electron relay layer may be provided between the P-type layer and the electron injection buffer layer. By forming the charge generation layer 106 using the materials described above, it is possible to suppress the increase in driving voltage when the EL layers are stacked.

[0256] In the charge generation layer 106, if an electron acceptor is added to a hole-transporting material which is an organic compound (P-type layer), the material shown in this embodiment can be used as the hole-transporting material. Examples of electron acceptors include F4-TCNQ and chloranil. Other examples include oxides of metals belonging to groups 4 through 8 of the periodic table. Specifically, examples include vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, molybdenum oxide, tungsten oxide, manganese oxide, and rhenium oxide. The acceptor material mentioned above may also be used. Furthermore, the P-type layer may be used as a mixed film by mixing the materials, or as single films containing each material stacked together.

[0257] Furthermore, in the charge generation layer 106, if an electron donor is added to the electron transport material (electron injection buffer layer), the material shown in this embodiment can be used as the electron transport material. In addition, organic compounds having a trisubstituted silyl group as described in Embodiment 1 and this embodiment can be used. In addition, alkali metals, alkaline earth metals, rare earth metals, or metals belonging to groups 2 and 13 of the periodic table, and their oxides and carbonates can be used as electron donors. Specifically, lithium (Li), cesium (Cs), magnesium (Mg), calcium (Ca), ytterbium (Yb), indium (In), lithium oxide (Li2O), cesium carbonate, etc. are preferred. In addition, alkali metal compounds such as Liq may be used. In addition, organic compounds such as tetrathianaphthalene may be used as electron donors. Furthermore, organic compounds having a 1,3,4,6,7,8-tetrahydro-2H-pyrimido[1,2-a]pyrimidine skeleton, such as 2hppSF, 2,7hpp2SF, and hpp2Py, may be used as electron donors. When these organic compounds are used as electron donors, it is preferable to use organic compounds containing heteroaromatic rings with a phenanthroline ring, such as BPhen, BCP, NBPhen, and 2,2'-(1,3-phenylene)bis(9-phenyl-1,10-phenanthroline) (abbreviated as mPPhen2P), as electron transport materials in combination, because this can reduce the driving voltage of the light-emitting device.

[0258] In the charge generation layer 106, when an electron relay layer is provided between the P-type layer and the electron injection buffer layer, the electron relay layer contains at least an electron-transporting material and has the function of preventing interaction between the electron injection buffer layer and the P-type layer and smoothly transferring electrons. Preferably, the LUMO level of the electron-transporting material included in the electron relay layer is between the LUMO level of the acceptor material in the P-type layer and the LUMO level of the electron-transporting material included in the electron transport layer in contact with the charge generation layer 106. The specific energy level of the LUMO level of the electron-transporting material used in the electron relay layer can be -5.00 eV or higher, preferably -5.00 eV or higher and -3.00 eV or lower. It is preferable to use a phthalocyanine-based material or a metal complex having a metal-oxygen bond and an aromatic ligand as the electron-transporting material used in the electron relay layer.

[0259] Furthermore, from the viewpoint of light extraction efficiency, it is preferable that the charge generation layer 106 is transparent to visible light (specifically, the transmittance of visible light to the charge generation layer 106 is 40% or more). In addition, the charge generation layer 106 can function even if its conductivity is lower than that of the first electrode 101 and the second electrode 102.

[0260] Although Figure 1(E) shows a configuration in which two EL layers 103 are stacked, a stacked structure of three or more EL layers may be used by providing a charge generation layer between different EL layers.

[0261] <Cap layer> Although not shown in Figures 1(A) to 1(F), a cap layer may be provided on the second electrode 102 of the light-emitting device. For example, a material with a high refractive index can be used for the cap layer. By providing a cap layer on the second electrode 102, the extraction efficiency of the light emitted from the second electrode 102 can be improved.

[0262] Specific examples of materials that can be used for the cap layer include 5,5'-diphenyl-2,2'-di-5H-[1]benzothieno[3,2-c]carbazole (abbreviated as BisBTc) and DBT3P-II.

[0263] <Circuit board> The light-emitting device shown in this embodiment can be formed on various substrates. The type of substrate is not limited to any particular type. Examples of substrates include semiconductor substrates (e.g., single crystal substrates or silicon substrates), SOI substrates, glass substrates, quartz substrates, plastic substrates, metal substrates, stainless steel substrates, substrates with stainless steel foil, tungsten substrates, substrates with tungsten foil, flexible substrates, laminated films, paper containing fibrous materials, or base films.

[0264] Examples of glass substrates include barium borosilicate glass, aluminobrosilicate glass, or soda-lime glass. Examples of flexible substrates, laminated films, and base films include plastics such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), and polyethersulfone (PES), synthetic resins such as acrylic resins, polypropylene, polyester, polyvinyl fluoride, or polyvinyl chloride, polyamide, polyimide, aramid, epoxy resins, inorganic vapor-deposited films, or paper.

[0265] In this embodiment, the light-emitting device can be fabricated using vapor-phase methods such as vapor deposition, spin coating, and liquid-phase methods such as inkjet. When using vapor deposition, physical vapor deposition methods (PVD) such as sputtering, ion plating, ion beam deposition, molecular beam deposition, and vacuum deposition, as well as chemical vapor deposition (CVD), can be used. In particular, the various functional layers included in the EL layer of the light-emitting device (hole injection layer 111, hole transport layer 112, light-emitting layer 113, electron transport layer 114, electron injection layer 115) can be formed by methods such as vapor deposition (vacuum deposition, etc.), coating (dip coating, die coating, bar coating, spin coating, spray coating, etc.), and printing (inkjet, screen printing, offset printing, flexographic printing, gravure printing, microcontact printing, etc.).

[0266] Furthermore, when applying the above-mentioned coating method, printing method, or other film formation method, polymer compounds (oligomers, dendrimers, polymers, etc.), medium-molecular-weight compounds (compounds in the intermediate region between low-molecular-weight and high-molecular-weight compounds: molecular weight 400 to 4000), inorganic compounds (quantum dot materials, etc.) can be used. As for quantum dot materials, colloidal quantum dot materials, alloy-type quantum dot materials, core-shell type quantum dot materials, core-type quantum dot materials, etc., can be used.

[0267] The layers constituting the EL layer 103 of the light-emitting device shown in this embodiment (hole injection layer 111, hole transport layer 112, light-emitting layer 113, electron transport layer 114, electron injection layer 115) are not limited to the materials shown in this embodiment, and other materials can be used in combination as long as they can satisfy the function of each layer.

[0268] The configuration shown in this embodiment can be used in appropriate combination with the configurations shown in other embodiments.

[0269] (Embodiment 3) This embodiment describes a display device according to one aspect of the present invention.

[0270] The display device of this embodiment can be a high-definition display device. Therefore, the display device of this embodiment can be used, for example, as a display unit for information terminals (wearable devices) such as wristwatches and bracelets, and as a display unit for wearable devices that can be worn on the head, such as VR devices such as head-mounted displays (HMDs) and AR devices such as glasses.

[0271] Furthermore, the display device of this embodiment can be a high-resolution display device or a large-screen display device. Therefore, the display device of this embodiment can be used in electronic devices with relatively large screens, such as television equipment, desktop or notebook personal computers, computer monitors, digital signage, and large game machines such as pachinko machines, as well as in the display units of digital cameras, digital video cameras, digital photo frames, mobile phones, portable game consoles, personal information terminals, and audio playback devices.

[0272] [Display Module] Figure 2(A) shows a perspective view of the display module 280. The display module 280 includes a display device 600A and an FPC 290. Note that the display device included in the display module 280 is not limited to the display device 600A, but may also be the display device 600B, which will be described later.

[0273] The display module 280 has substrates 291 and 292. The display module 280 has a display unit 281. The display unit 281 is an area in the display module 280 that displays an image, and is an area in which light from each pixel provided in the pixel unit 284, which will be described later, can be seen.

[0274] Figure 2(B) shows a schematic perspective view illustrating the configuration of the substrate 291. On the substrate 291, a circuit section 282, a pixel circuit section 283 on the circuit section 282, and a pixel section 284 on the pixel circuit section 283 are stacked. In addition, a terminal section 285 for connecting to the FPC 290 is provided in the portion of the substrate 291 that does not overlap with the pixel section 284. The terminal section 285 and the circuit section 282 are electrically connected by a wiring section 286, which is composed of multiple wires.

[0275] The pixel section 284 has a plurality of pixels 284a arranged periodically. A magnified view of one pixel 284a is shown on the right side of Figure 2(B). Various configurations described in the previous embodiment can be applied to the pixels 284a.

[0276] The pixel circuit section 283 has a plurality of pixel circuits 283a arranged periodically.

[0277] A single pixel circuit 283a is a circuit that controls the driving of multiple elements in a single pixel 284a. A single pixel circuit 283a can be configured to have three circuits that control the light emission of a single light-emitting device. For example, a single pixel circuit 283a can be configured to have at least one selection transistor, one current control transistor (driving transistor), and a capacitor for each light-emitting device. In this case, a gate signal is input to the gate of the selection transistor, and a video signal is input to the source or drain. This realizes an active-matrix type display device.

[0278] The circuit section 282 has circuits for driving each pixel circuit 283a of the pixel circuit section 283. For example, it is preferable to have one or both of a gate line drive circuit and a source line drive circuit. In addition, it may have at least one of the following: an arithmetic circuit, a memory circuit, and a power supply circuit.

[0279] The FPC290 functions as wiring for supplying video signals or power potential, etc., to the circuit section 282 from an external source. An IC may also be mounted on the FPC290.

[0280] The display module 280 can be configured such that one or both of the pixel circuit section 283 and the circuit section 282 are stacked on the lower side of the pixel section 284, thereby enabling an extremely high aperture ratio (effective display area ratio) of the display section 281. For example, the aperture ratio of the display section 281 can be 40% or more and less than 100%, preferably 50% or more and 95%, and more preferably 60% or more and 95%. Furthermore, it is possible to arrange the pixels 284a at an extremely high density, enabling an extremely high resolution of the display section 281. For example, it is preferable that the pixels 284a are arranged in the display section 281 with a resolution of 20000 ppi or more, preferably 3000 ppi or more, more preferably 5000 ppi or more, and even more preferably 6000 ppi or more, and a resolution of 20000 ppi or less, or 30000 ppi or less.

[0281] Furthermore, pixel 284a has sub-pixels 110R, 110G, and 110B.

[0282] In this specification, for example, when describing matters common to sub-pixels 110R, 110G, and 110B, they may be referred to simply as sub-pixel 110. Similarly, when describing matters common to other components distinguished by letters, the letters may be omitted and the corresponding symbols used.

[0283] Sub-pixel 110R emits red light, sub-pixel 110G emits green light, and sub-pixel 110B emits blue light. This allows an image to be displayed on the pixel section 177. In this embodiment, three sub-pixels of red (R), green (G), and blue (B) are used as an example, but other combinations of sub-pixels of other colors may be used. Furthermore, the number of sub-pixels is not limited to three, but may be four or more. Examples of four sub-pixels include four sub-pixels of R, G, B, and white (W), four sub-pixels of R, G, B, and Y, and four sub-pixels of R, G, B, and infrared (IR).

[0284] Because such a display module 280 is extremely high-resolution, it can be suitably used in VR devices such as HMDs or AR devices such as glasses. For example, even in a configuration where the display part of the display module 280 is viewed through lenses, the display module 280 has an extremely high-resolution display part 281, so even when the display part is magnified with lenses, pixels are not visible, and a highly immersive display can be achieved. Furthermore, the display module 280 is not limited to this and can be suitably used in electronic devices with relatively small display parts. For example, it can be suitably used in the display part of wearable electronic devices such as watches.

[0285] [Display device 600A] The display device 600A shown in Figure 3(A) comprises a substrate 301, light-emitting devices 130R, 130G, 130B, a capacitor 240, and a transistor 310.

[0286] Substrate 301 corresponds to substrate 291 in Figures 2(A) and 2(B). Transistor 310 is a transistor having a channel formation region in substrate 301. For example, a semiconductor substrate such as a single-crystal silicon substrate can be used as substrate 301. Transistor 310 has a part of substrate 301, a conductive layer 311, a low-resistance region 312, an insulating layer 313, and an insulating layer 314. The conductive layer 311 functions as a gate electrode. The insulating layer 313 is located between substrate 301 and the conductive layer 311 and functions as a gate insulating layer. The low-resistance region 312 is a region of substrate 301 doped with impurities and functions as a source or drain. The insulating layer 314 is provided covering the side surface of the conductive layer 311.

[0287] Furthermore, an element isolation layer 315 is provided between two adjacent transistors 310 so as to be embedded in the substrate 301.

[0288] Furthermore, an insulating layer 261 is provided covering the transistor 310, and a capacitance 240 is provided on the insulating layer 261.

[0289] The capacitor 240 has a conductive layer 241, a conductive layer 245, and an insulating layer 243 located between them. The conductive layer 241 acts as one electrode of the capacitor 240, the conductive layer 245 acts as the other electrode of the capacitor 240, and the insulating layer 243 acts as the dielectric of the capacitor 240.

[0290] The conductive layer 241 is provided on the insulating layer 261 and embedded in the insulating layer 254. The conductive layer 241 is electrically connected to either the source or drain of the transistor 310 by a plug 271 embedded in the insulating layer 261. The insulating layer 243 is provided covering the conductive layer 241. The conductive layer 245 is provided in the region that overlaps with the conductive layer 241 via the insulating layer 243.

[0291] An insulating layer 255 is provided covering the capacitance 240, an insulating layer 174 is provided on the insulating layer 255, and an insulating layer 175 is provided on the insulating layer 174. Light-emitting devices 130R, 130G, and 130B are provided on the insulating layer 175. Light-emitting devices 130R, 130G, and 130B each have the configuration shown in Embodiment 2. An insulator is provided in the region between adjacent light-emitting devices. For example, in Figure 3(A), an inorganic insulating layer 125 and an insulating layer 127 on the inorganic insulating layer 125 are provided in this region.

[0292] Light-emitting device 130R has a first electrode consisting of a conductive layer 151R and a conductive layer 152R, an EL layer 103R on the first electrode, and a common layer 155 on the EL layer 103R. Light-emitting device 130G has a first electrode consisting of a conductive layer 151G and a conductive layer 152G, an EL layer 103G on the first electrode, and a common layer 155 on the EL layer 103G. Light-emitting device 130B has a first electrode consisting of a conductive layer 151B and a conductive layer 152B, an EL layer 103B on the first electrode, and a common layer 155 on the EL layer 103B. Furthermore, a sacrificial layer 158R is located on the EL layer 103R of the light-emitting device 130R, a sacrificial layer 158G is located on the EL layer 103G of the light-emitting device 130G, and a sacrificial layer 158B is located on the EL layer 103B of the light-emitting device 130B. A common layer 155 shared by each light-emitting device includes at least a second electrode. The common layer 155 may have an electron injection layer located between the second electrode and each EL layer. For example, light-emitting device 130R can emit red light, light-emitting device 130G can emit green light, and light-emitting device 130B can emit blue light. In this specification, when describing matters common to light-emitting devices 130R, 130G, and 130B, they may be referred to as light-emitting device 130. In this specification, when describing matters common to conductive layer 151R, conductive layer 151G, and conductive layer 151B, they may be referred to as conductive layer 151. In this specification, when describing matters common to conductive layer 152R, conductive layer 152G, and conductive layer 152B, they may be referred to as conductive layer 152.

[0293] Of the first and second electrodes of the light-emitting device 130, one functions as the anode and the other as the cathode. In the following description, unless otherwise specified, it is assumed that the first electrode functions as the anode and the second electrode functions as the cathode.

[0294] Each EL layer of the light-emitting device 130 is independently arranged in an island-like configuration for each light-emitting device or for each light-emitting color. By providing the EL layer 103 in an island-like configuration for each light-emitting device 130, leakage current between adjacent light-emitting devices 130 can be suppressed even in high-definition display devices. This prevents crosstalk and enables the realization of a display device with extremely high contrast. In particular, it enables the realization of a display device with high current efficiency at low brightness.

[0295] Furthermore, in a display device according to one aspect of the present invention, it is preferable that the first electrode (pixel electrode) of the light-emitting device be in a stacked configuration. For example, in the example shown in Figure 3(B), the first electrode of the light-emitting device 130 is in a stacked configuration of a conductive layer 151 and a conductive layer 152. For example, when the display device 600A is of the top emission type and the pixel electrode of the light-emitting device 130 functions as an anode, it is preferable that the conductive layer 151 is a layer with high reflectivity for visible light, and the conductive layer 152 is a layer that, for example, transmits visible light and has a large work function. When the display device 600A is of the top emission type, the higher the reflectivity of the pixel electrode for visible light, the higher the efficiency of extracting light emitted by the EL layer 103. Also, when the pixel electrode functions as an anode, the larger the work function of the pixel electrode, the easier it is to inject holes into the EL layer 103. Based on the above, by making the pixel electrodes of the light-emitting device 130 a stacked structure consisting of a conductive layer 151 with high reflectivity for visible light and a conductive layer 152 with a large work function, the light-emitting device 130 can be made into a light-emitting device with high light extraction efficiency and low driving voltage.

[0296] When the conductive layer 151 is a layer with high reflectivity to visible light, it is preferable that the reflectivity of the conductive layer 151 to visible light be, for example, 40% to 100% or 70% to 100%. Furthermore, when the conductive layer 152 is an electrode that transmits visible light, it is preferable that its transmittance to visible light be, for example, 40% or more.

[0297] In cases where the pixel electrode has a stacked structure consisting of multiple layers, the pixel electrode may be altered due to reactions between these layers, for example. For instance, when a film formed after the pixel electrode is created is removed by a wet etching method, galvanic corrosion may occur when the chemical solution comes into contact with the pixel electrode.

[0298] Therefore, in the display device 600A of this embodiment, insulating layers 156 (156R, 156G, 156B) are formed on the sides of the conductive layers 151 and 152. This makes it possible to suppress contact of the chemical solution with the conductive layer 151 even when removing a film formed after the formation of a pixel electrode having the conductive layer 151 and the conductive layer 152 by a wet etching method. Thus, for example, the occurrence of galvanic corrosion on the pixel electrode can be suppressed. As a result, the display device 600A can be manufactured using a method with a high yield, making it a low-cost display device. Furthermore, since the occurrence of defects in the display device 600A can be suppressed, the display device 600A can be a highly reliable display device. Note that in this specification, when describing matters common to insulating layers 156R, insulating layer 156G, and insulating layer 156B, they may be referred to as insulating layer 156.

[0299] For example, a metallic material can be used as the conductive layer 151. Specifically, metals such as aluminum (Al), titanium (Ti), chromium (Cr), manganese (Mn), iron (Fe), cobalt (Co), nickel (Ni), copper (Cu), gallium (Ga), zinc (Zn), indium (In), tin (Sn), molybdenum (Mo), tantalum (Ta), tungsten (W), palladium (Pd), gold (Au), platinum (Pt), silver (Ag), yttrium (Y), neodymium (Nd), and alloys containing these in appropriate combinations can also be used.

[0300] As the conductive layer 152, an oxide having one or more selected from indium, tin, zinc, gallium, titanium, aluminum, and silicon can be used. For example, it is preferable to use a conductive oxide containing one or more of the following: indium oxide, indium tin oxide, indium zinc oxide, zinc oxide, zinc oxide containing gallium, titanium oxide, indium zinc oxide containing gallium, indium zinc oxide containing aluminum, indium tin oxide containing silicon, and indium zinc oxide containing silicon. In particular, indium tin oxide containing silicon has a large work function, for example, a work function of 4.0 eV or more, so it can be suitably used as the conductive layer 152.

[0301] The conductive layer 151 is electrically connected to either the source or drain of the transistor 310 by the insulating layer 243, insulating layer 255, insulating layer 174, and a plug 256 embedded in the insulating layer 175, a conductive layer 241 embedded in the insulating layer 254, and a plug 271 embedded in the insulating layer 261. The height of the upper surface of the insulating layer 175 and the height of the upper surface of the plug 256 are equal or approximately equal. Various conductive materials can be used for the plugs.

[0302] Furthermore, a protective layer 135 is provided on the light-emitting device 130. A substrate 120 is bonded to the protective layer 135 by a resin layer 122. The substrate 120 corresponds to the substrate 292 in Figure 2(A).

[0303] Figure 3(B) shows a modified example of the display device 600A shown in Figure 3(A). The display device shown in Figure 3(B) has a colored layer 136R, a colored layer 136G, and a colored layer 136B, and the light-emitting device 130 has a region that overlaps with one of the colored layers 136R, 136G, and 136B. In the display device shown in Figure 3(B), the light-emitting device 130 can emit, for example, white light. Also, for example, the colored layer 136R can transmit red light, the colored layer 136G can transmit green light, and the colored layer 136B can transmit blue light.

[0304] [Display device 600B] Figure 4 shows a perspective view of the display device 600B, and Figure 5 shows a cross-sectional view of the display device 600B.

[0305] The display device 600B has a configuration in which substrate 352 and substrate 351 are bonded together. In Figure 4, substrate 352 is clearly indicated by a dashed line.

[0306] The display device 600B includes a pixel section 177, a connection section 140, a circuit 356, and wiring 355, etc. Figure 4 shows an example in which an IC (integrated circuit) 354 and an FPC 353 are mounted on the display device 600B. Therefore, the configuration shown in Figure 4 can also be called a display module having the display device 600B, an IC, and an FPC. Here, a display module is defined as a display device with a connector such as an FPC attached to its substrate, or a substrate on which an IC is mounted.

[0307] The connection portion 140 is provided on the outside of the pixel portion 177. The connection portion 140 can be provided along one or more sides of the pixel portion 177. There may be one or more connection portions 140. Figure 4 shows an example in which the connection portion 140 is provided so as to surround all four sides of the pixel portion 177. At the connection portion 140, the common electrode of the light-emitting device and the conductive layer are electrically connected, and a potential can be supplied to the common electrode.

[0308] For example, a scan line drive circuit can be used as circuit 356.

[0309] The wiring 355 has the function of supplying signals and power to the pixel unit 177 and the circuit 356. These signals and power are input to the wiring 355 from an external source via the FPC 353 or from the IC 354.

[0310] Figure 4 shows an example in which IC 354 is mounted on substrate 351 using a COG (Chip On Glass) method or COF (Chip On Film) method, etc. IC 354 can be an IC having, for example, a scan line drive circuit or a signal line drive circuit. Note that the display device 600B and the display module may be configured without an IC. Alternatively, the IC may be mounted on an FPC, for example, using a COF method.

[0311] Figure 5 shows an example of a cross-section of the display device 600B when a portion of the area including the FPC 353, a portion of the circuit 356, a portion of the pixel portion 177, a portion of the connection portion 140, and a portion of the area including the end portion are cut.

[0312] The display device 600B shown in Figure 5 has a transistor 201, a transistor 205, a light-emitting device 130R that emits red light, a light-emitting device 130G that emits green light, and a light-emitting device 130B that emits blue light, etc., between substrates 351 and 352.

[0313] Light-emitting devices 130R, 130G, and 130B each have the stacked structure shown in Figure 1(A), except that they differ in the configuration of their pixel electrodes. Details of the light-emitting devices can be found in the previous embodiment.

[0314] Light-emitting device 130R has a conductive layer 224R, a conductive layer 151R on the conductive layer 224R, and a conductive layer 152R on the conductive layer 151R. Light-emitting device 130G has a conductive layer 224G, a conductive layer 151G on the conductive layer 224G, and a conductive layer 152G on the conductive layer 151G. Light-emitting device 130B has a conductive layer 224B, a conductive layer 151B on the conductive layer 224B, and a conductive layer 152B on the conductive layer 151B. Here, the conductive layers 224R, 151R, and 152R can all be collectively called the pixel electrodes of light-emitting device 130R, and the conductive layers 151R and 152R excluding the conductive layer 224R can also be called the pixel electrodes of light-emitting device 130R. Similarly, conductive layers 224G, 151G, and 152G can all be collectively referred to as the pixel electrodes of the light-emitting device 130G, and conductive layers 151G and 152G (excluding conductive layer 224G) can also be referred to as the pixel electrodes of the light-emitting device 130G. Furthermore, conductive layers 224B, 151B, and 152B can all be collectively referred to as the pixel electrodes of the light-emitting device 130B, and conductive layers 151B and 152B (excluding conductive layer 224B) can also be referred to as the pixel electrodes of the light-emitting device 130B.

[0315] The conductive layer 224R is connected to the conductive layer 222b of the transistor 205 through an opening provided in the insulating layer 214. The edge of the conductive layer 151R is located outside the edge of the conductive layer 224R. The insulating layer 156R is provided so as to have a region in contact with the side surface of the conductive layer 151R, and the conductive layer 152R is provided so as to cover the conductive layer 151R and the insulating layer 156R.

[0316] The conductive layers 224G, 151G, 152G, and insulating layer 156G in the light-emitting device 130G, and the conductive layers 224B, 151B, 152B, and insulating layer 156B in the light-emitting device 130B are the same as the conductive layers 224R, 151R, 152R, and insulating layer 156R in the light-emitting device 130R, so a detailed explanation is omitted.

[0317] The conductive layer 224R, conductive layer 224G, and conductive layer 224B have recesses formed to cover the openings provided in the insulating layer 214. Layer 128 is embedded in these recesses.

[0318] Layer 128 has the function of flattening the recesses of conductive layers 224R, 224G, and 224B. Conductive layers 151R, 151G, and 151B are provided on conductive layers 224R, 224G, and 224B and on layer 128, and are electrically connected to conductive layers 224R, 224G, and 224B. Therefore, regions overlapping with the recesses of conductive layers 224R, 224G, and 224B can also be used as light-emitting regions, thereby increasing the aperture ratio of the pixels.

[0319] Layer 128 may be an insulating layer or a conductive layer. Various inorganic insulating materials, organic insulating materials, and conductive materials can be used for layer 128 as appropriate. In particular, it is preferable that layer 128 be formed using an insulating material, and especially preferable that it be formed using an organic insulating material. For example, an organic insulating material that can be used for the insulating layer 127 described above can be applied to layer 128.

[0320] A protective layer 135 is provided on the light-emitting devices 130R, 130G, and 130B. The protective layer 135 and the substrate 352 are bonded via an adhesive layer 142. A light-shielding layer 157 is provided on the substrate 352. A solid encapsulation structure or a hollow encapsulation structure can be applied to encapsulate the light-emitting devices 130. In Figure 5, the space between the substrate 352 and the substrate 351 is filled with the adhesive layer 142, indicating a solid encapsulation structure. Alternatively, the space may be filled with an inert gas (such as nitrogen or argon), indicating a hollow encapsulation structure. In this case, the adhesive layer 142 may be provided in a frame shape so as not to overlap with the light-emitting devices. Furthermore, the space may be filled with a resin different from the adhesive layer 142 provided in a frame shape.

[0321] Figure 5 shows an example in which the connection portion 140 has a conductive layer 224C obtained by processing the same conductive film as conductive layers 224R, 224G, and 224B; a conductive layer 151C obtained by processing the same conductive film as conductive layers 151R, 151G, and 151B; and a conductive layer 152C obtained by processing the same conductive film as conductive layers 152R, 152G, and 152B. Figure 5 also shows an example in which an insulating layer 156C is provided so as to have a region that overlaps with the side surface of conductive layer 151C.

[0322] The display device 600B is a top-emission type. The light emitted by the light-emitting device is emitted towards the substrate 352. It is preferable to use a material with high transmittance to visible light for the substrate 352. The pixel electrodes contain a material that reflects visible light, and the counter electrodes (common layer 155) contain a material that transmits visible light.

[0323] Both transistors 201 and 205 are formed on the substrate 351. These transistors can be manufactured using the same materials and processes.

[0324] On the substrate 351, insulating layers 211, 213, 215, and 214 are provided in this order. A portion of insulating layer 211 functions as a gate insulating layer for each transistor. A portion of insulating layer 213 functions as a gate insulating layer for each transistor. Insulating layer 215 is provided covering the transistors. Insulating layer 214 is provided covering the transistors and functions as a planarization layer. The number of gate insulating layers and insulating layers covering the transistors are not limited and may be a single layer or two or more layers, respectively.

[0325] It is preferable to use a material that does not easily allow impurities such as water and hydrogen to diffuse into at least one layer of the insulating layer covering the transistor. This allows the insulating layer to function as a barrier layer. With such a configuration, the diffusion of impurities from the outside into the transistor can be effectively suppressed, thereby improving the reliability of the display device.

[0326] It is preferable to use inorganic insulating films for insulating layer 211, insulating layer 213, and insulating layer 215. Examples of inorganic insulating films that can be used include silicon nitride film, silicon oxynitride film, silicon oxide film, silicon nitride oxide film, aluminum oxide film, or aluminum nitride film. Alternatively, hafnium oxide film, yttrium oxide film, zirconium oxide film, gallium oxide film, tantalum oxide film, magnesium oxide film, lanthanum oxide film, cerium oxide film, and neodymium oxide film may also be used. Furthermore, two or more of the above insulating films may be laminated together.

[0327] An organic insulating layer is preferred for the insulating layer 214, which functions as a planarizing layer. Examples of materials that can be used for the organic insulating layer include acrylic resin, polyimide resin, epoxy resin, polyamide resin, polyimidoamide resin, siloxane resin, benzocyclobutene resin, phenol resin, and precursors of these resins. Alternatively, the insulating layer 214 may have a laminated structure of an organic insulating layer and an inorganic insulating layer. The outermost layer of the insulating layer 214 preferably functions as an etching protection layer. This suppresses the formation of depressions in the insulating layer 214 during processing of the conductive layer 224R, conductive layer 151R, or conductive layer 152R, etc. Alternatively, depressions may be provided in the insulating layer 214 during processing of the conductive layer 224R, conductive layer 151R, or conductive layer 152R, etc.

[0328] Transistors 201 and 205 have a conductive layer 221 that functions as a gate, an insulating layer 211 that functions as a gate insulating layer, conductive layers 222a and 222b that function as source and drain, a semiconductor layer 231, an insulating layer 213 that functions as a gate insulating layer, and a conductive layer 223 that functions as a gate. Here, the same hatching pattern is applied to multiple layers obtained by processing the same conductive film. The insulating layer 211 is located between the conductive layer 221 and the semiconductor layer 231. The insulating layer 213 is located between the conductive layer 223 and the semiconductor layer 231.

[0329] The transistor structure of the display device of this embodiment is not particularly limited. For example, a planar transistor, a staggered transistor, or an inverse staggered transistor can be used. Furthermore, either a top-gate or bottom-gate transistor structure may be used. Alternatively, gates may be provided above and below the semiconductor layer in which the channel is formed.

[0330] Transistors 201 and 205 are configured in which a semiconductor layer on which a channel is formed is sandwiched between two gates. The transistors may be driven by connecting the two gates and supplying them with the same signal. Alternatively, the threshold voltage of the transistors may be controlled by applying a potential to control the threshold voltage to one of the two gates and a potential to drive the other gate.

[0331] The crystallinity of the semiconductor material used in the transistor is not particularly limited; amorphous semiconductors, crystalline semiconductors (microcrystalline semiconductors, polycrystalline semiconductors, single-crystal semiconductors, or semiconductors having a crystalline region in part) may be used. Using a crystalline semiconductor is preferable because it can suppress the degradation of transistor characteristics.

[0332] The semiconductor layer of the transistor preferably has a metal oxide. In other words, the display device of this embodiment preferably uses a transistor (hereinafter referred to as an OS transistor) that uses a metal oxide in the channel formation region.

[0333] Examples of crystalline oxide semiconductors include CAAC (c-axis-aligned crystalline)-OS and nc (nanocrystalline)-OS.

[0334] Alternatively, a transistor using silicon as the channel-forming region (Si transistor) may be used. Examples of silicon include single-crystal silicon, polycrystalline silicon, or amorphous silicon. In particular, a transistor having low-temperature polysilicon (LTPS (Low Temperature Poly Silicon)) in the semiconductor layer (hereinafter also referred to as an LTPS transistor) can be used. LTPS transistors have high field-effect mobility and good frequency characteristics.

[0335] By using Si transistors such as LTPS transistors, circuits that need to be driven at high frequencies (e.g., source driver circuits) can be fabricated on the same board as the display unit. This simplifies the external circuits implemented in the display device, reducing component and mounting costs.

[0336] OS transistors have extremely high field-effect mobility compared to transistors using amorphous silicon. Furthermore, OS transistors exhibit remarkably low source-drain leakage current in the off state, allowing them to retain charge stored in a capacitor connected in series with the transistor for extended periods. Additionally, the application of OS transistors can reduce the power consumption of display devices.

[0337] Furthermore, to increase the luminescence brightness of the light-emitting device included in the pixel circuit, it is necessary to increase the amount of current flowing through the light-emitting device. To achieve this, it is necessary to increase the source-drain voltage of the drive transistor included in the pixel circuit. Compared to Si transistors, OS transistors have a higher breakdown voltage between the source and drain, so a higher voltage can be applied between the source and drain of an OS transistor. Therefore, by using an OS transistor as the drive transistor included in the pixel circuit, the amount of current flowing through the light-emitting device can be increased, thereby increasing the luminescence brightness of the light-emitting device.

[0338] Furthermore, in terms of the saturation characteristics of the current flowing when a transistor operates in the saturation region, OS transistors can supply a more stable current (saturation current) than Si transistors, even when the source-drain voltage gradually increases. Therefore, by using an OS transistor as a driving transistor, a stable current can be supplied to a light-emitting device even if there are variations in the current-voltage characteristics of the light-emitting device. In other words, when operating in the saturation region, the source-drain current remains almost unchanged even when the source-drain voltage is increased, thus stabilizing the luminescence brightness of the light-emitting device.

[0339] As described above, by using OS transistors in the drive transistors included in the pixel circuit, it is possible to achieve "suppression of black level floating," "increase in luminescence brightness," "multi-gradation," and "suppression of variations in light-emitting devices."

[0340] The semiconductor layer preferably comprises, for example, indium, M (where M is one or more 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, it is preferable that M is one or more selected from aluminum, gallium, yttrium, and tin.

[0341] In particular, it is preferable to use an oxide containing indium (In), gallium (Ga), and zinc (Zn) (also written as IGZO) as the semiconductor layer. Alternatively, it is preferable to use an oxide containing indium, tin, and zinc. Alternatively, it is preferable to use an oxide containing indium, gallium, tin, and zinc. Alternatively, it is preferable to use an oxide containing indium (In), aluminum (Al), and zinc (Zn) (also written as IAZO). Alternatively, it is preferable to use an oxide containing indium (In), aluminum (Al), gallium (Ga), and zinc (Zn) (also written as IAGZO). Alternatively, it is preferable to use an oxide containing indium (In) (also written as IO).

[0342] When the semiconductor layer is an In-M-Zn oxide, it is preferable that the atomic ratio of In in the In-M-Zn oxide is equal to or greater than the atomic ratio of M. Examples of atomic ratios of metal elements in such In-M-Zn oxides include compositions where In:M:Zn=1:1:1 or close to it, In:M:Zn=1:1:1.2 or close to it, In:M:Zn=2:1:3 or close to it, In:M:Zn=3:1:2 or close to it, In:M:Zn=4:2:3 or close to it, In:M:Zn=4:2:4.1 or close to it, In:M:Zn=5:1:3 or close to it, In:M:Zn=5:1:6 or close to it, In:M:Zn=5:1:7 or close to it, In:M:Zn=5:1:8 or close to it, In:M:Zn=6:1:6 or close to it, In:M:Zn=5:2:5 or close to it, and so on. Note that "nearby composition" includes a range of ±30% of the desired atomic ratio.

[0343] When the atomic ratio is stated as In:Ga:Zn=4:2:3 or nearby, it includes cases where, with In set to 4, Ga is between 1 and 3, and Zn is between 2 and 4. Furthermore, when the atomic ratio is stated as In:Ga:Zn=5:1:6 or nearby, it includes cases where, with In set to 5, Ga is greater than 0.5 and 2 or less, and Zn is between 5 and 7. Furthermore, when the atomic ratio is stated as In:Ga:Zn=1:1:1 or nearby, it includes cases where, with In set to 1, Ga is greater than 0.5 and 2 or less, and Zn is greater than 0.5 and 2 or less.

[0344] The transistors in circuit 356 and the transistors in pixel unit 177 may have the same structure or different structures. The structures of the multiple transistors in circuit 356 may all be the same or there may be two or more different structures. Similarly, the structures of the multiple transistors in pixel unit 177 may all be the same or there may be two or more different structures.

[0345] All of the transistors in the pixel section 177 may be OS transistors, all of the transistors in the pixel section 177 may be Si transistors, or some of the transistors in the pixel section 177 may be OS transistors and the rest may be Si transistors.

[0346] For example, by using both LTPS transistors and OS transistors in the pixel section 177, a display device with low power consumption and high driving capability can be realized. Furthermore, a configuration combining LTPS transistors and OS transistors is sometimes referred to as LTPO. It is preferable, for example, to use an OS transistor as a switch to control the conduction and non-conductivity of wiring, and an LTPS transistor as a transistor to control current.

[0347] For example, one of the transistors in the pixel section 177 functions as a transistor for controlling the current flowing to the light-emitting device and can be called a drive transistor. One of the source and drain of the drive transistor is electrically connected to the pixel electrode of the light-emitting device. It is preferable to use an LTPS transistor for this drive transistor. This makes it possible to increase the current flowing to the light-emitting device in the pixel circuit.

[0348] On the other hand, the other transistor in the pixel unit 177 functions as a switch to control the selection and deselection of pixels, and can also be called a selection transistor. The gate of the selection transistor is electrically connected to the gate line, and one of the source and drain is electrically connected to the source line (signal line). It is preferable to use an OS transistor for the selection transistor. This allows the pixel gradation to be maintained even when the frame frequency is significantly reduced (e.g., 1 fps or less), and thus power consumption can be reduced by stopping the driver when displaying still images.

[0349] Thus, a display device according to one aspect of the present invention can combine a high aperture ratio, high resolution, high display quality, and low power consumption.

[0350] Furthermore, one embodiment of the present invention is a display device having an OS transistor and a light-emitting device with an MML (metal maskless) structure. This configuration makes it possible to extremely low leakage current that can flow through the transistor and leakage current that can flow between adjacent light-emitting devices (sometimes referred to as lateral leakage current, transverse leakage current, or lateral leakage current). With this configuration, when an image is displayed on the display device, the observer can observe one or more of the following: image sharpness, image clarity, high saturation, and high contrast ratio. Moreover, by having an extremely low leakage current that can flow through the transistor and transverse leakage current between light-emitting devices, it is possible to achieve a display with as little light leakage (so-called black floating) that may occur when displaying black as possible.

[0351] In particular, among MML-structured light-emitting devices, applying the SBS (Side By Side) structure, which involves creating or coating different light-emitting layers, results in a configuration where the layers between light-emitting devices (for example, an organic layer used in common between light-emitting devices, also called a common layer) are separated, thus eliminating or significantly reducing side leakage.

[0352] A connection portion 204 is provided in the region of substrate 351 where substrate 352 does not overlap. At the connection portion 204, the wiring 355 is electrically connected to the FPC 353 via the conductive layer 166 and the connecting layer 242. The conductive layer 166 is shown as an example of a laminated structure consisting of a conductive film obtained by processing the same conductive film as conductive layers 224R, 224G, and 224B, a conductive film obtained by processing the same conductive film as conductive layers 151R, 151G, and 151B, and a conductive film obtained by processing the same conductive film as conductive layers 152R, 152G, and 152B. On the upper surface of the connection portion 204, the conductive layer 166 is exposed. This allows the connection portion 204 and the FPC 353 to be electrically connected via the connecting layer 242.

[0353] It is preferable to provide a light-shielding layer 157 on the surface of the substrate 352 that faces the substrate 351. The light-shielding layer 157 can be provided between adjacent light-emitting devices, at connection points 140, and in circuits 356, etc. In addition, various optical components can be arranged on the outside of the substrate 352.

[0354] Materials that can be used for substrate 120 can be applied to substrate 351 and substrate 352, respectively.

[0355] As the adhesive layer 142, a material that can be used for the resin layer 122 can be applied.

[0356] As the connecting layer 242, an anisotropic conductive film (ACF) or an anisotropic conductive paste (ACP) can be used.

[0357] [Display device 600C] The display device 600C shown in Figure 6 differs from the display device 600B shown in Figure 5 mainly in that it is a bottom-emission type display device.

[0358] The light emitted by the light-emitting device is projected onto the substrate 351. It is preferable to use a material with high transparency to visible light for the substrate 351. On the other hand, the light transmittance of the material used for the substrate 352 is not a requirement.

[0359] It is preferable to form a light-shielding layer 157 between the substrate 351 and the transistor 201, and between the substrate 351 and the transistor 205. Figure 6 shows an example in which a light-shielding layer 157 is provided on the substrate 351, an insulating layer 153 is provided on the light-shielding layer 157, and transistors 201, 205, etc. are provided on the insulating layer 153.

[0360] The light-emitting device 130R includes a conductive layer 112R, a conductive layer 126R on the conductive layer 112R, and a conductive layer 129R on the conductive layer 126R.

[0361] The light-emitting device 130B includes a conductive layer 112B, a conductive layer 126B on the conductive layer 112B, and a conductive layer 129B on the conductive layer 126B.

[0362] The conductive layers 112R, 112B, 126R, 126B, 129R, and 129B are made of materials with high transmittance to visible light. It is preferable to use a material that reflects visible light for the common layer 155.

[0363] Although the light-emitting device 130G is not shown in Figure 6, it is also provided.

[0364] Furthermore, while Figure 6 and other figures show an example where the upper surface of layer 128 has a flat portion, the shape of layer 128 is not particularly limited.

[0365] This embodiment can be appropriately combined with other embodiments or examples. Furthermore, if multiple configuration examples are shown within a single embodiment in this specification, these configuration examples can be appropriately combined.

[0366] (Embodiment 4) This embodiment describes an electronic device according to one aspect of the present invention.

[0367] The electronic device of this embodiment has a display device according to one aspect of the present invention in its display unit. The display device according to one aspect of the present invention is highly reliable and can be easily made high-definition and high-resolution. Therefore, it can be used in the display units of various electronic devices.

[0368] Examples of electronic devices include television sets, desktop or notebook personal computers, computer monitors, digital signage, large game machines such as pachinko machines, and other electronic devices with relatively large screens, as well as digital cameras, digital video cameras, digital photo frames, mobile phones, portable game consoles, personal digital assistants, and audio playback devices.

[0369] In particular, a display device according to one aspect of the present invention can be used suitably in electronic devices having a relatively small display area because it can increase the resolution. Examples of such electronic devices include wristwatch-type and bracelet-type information terminals (wearable devices), as well as wearable devices that can be worn on the head, such as VR devices such as head-mounted displays, AR devices such as glasses, and MR devices.

[0370] A display device according to one aspect of the present invention preferably has an extremely high resolution such as HD (1280 x 720 pixels), FHD (1920 x 1080 pixels), WQHD (2560 x 1440 pixels), WQXGA (2560 x 1600 pixels), 4K (3840 x 2160 pixels), or 8K (7680 x 4320 pixels). In particular, a resolution of 4K, 8K, or higher is preferred. Furthermore, the pixel density (resolution) of the display device according to one aspect of the present invention is preferably 100 ppi or more, preferably 300 ppi or more, more preferably 500 ppi or more, more preferably 1000 ppi or more, more preferably 2000 ppi or more, more preferably 3000 ppi or more, more preferably 5000 ppi or more, and even more preferably 7000 ppi or more. By using a display device having either high resolution or high detail, or both, it becomes possible to further enhance the sense of presence and depth. Furthermore, there are no particular limitations on the screen ratio (aspect ratio) of the display device according to one embodiment of the present invention. For example, the display device can support various screen ratios such as 1:1 (square), 4:3, 16:9, and 16:10.

[0371] The electronic device of this embodiment may have sensors (including those with functions to measure force, displacement, position, velocity, acceleration, angular velocity, rotational speed, distance, light, liquid, magnetism, temperature, chemical substances, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared radiation).

[0372] The electronic device of this embodiment can have a variety of functions. For example, it can have a function to display various information (still images, videos, text images, etc.) on the display unit, a touch panel function, a function to display a calendar, date or time, a function to execute various software (programs), a wireless communication function, a function to read programs or data recorded on a recording medium, and so on.

[0373] Figures 7(A) and 7(B) illustrate an example of a wearable device that can be worn on the head. These wearable devices have at least one of the following functions: a function to display AR content, a function to display VR content, a function to display SR content, and a function to display MR content. By having an electronic device that has the function to display at least one of the following content types, such as AR, VR, SR, and MR, it is possible to enhance the user's sense of immersion.

[0374] The electronic device 700A shown in Figure 7(A) and the electronic device 700B shown in Figure 7(B) each include a pair of display panels 751, a pair of housings 721, a communication unit (not shown), a pair of mounting units 723, a control unit (not shown), an imaging unit (not shown), a pair of optical members 753, a frame 757, and a pair of nose pads 758.

[0375] A display device according to one embodiment of the present invention can be applied to the display panel 751. Therefore, a highly reliable electronic device can be made.

[0376] Electronic devices 700A and 700B can project an image displayed on the display panel 751 onto the display area 756 of the optical element 753. Because the optical element 753 is translucent, the user can see the image displayed on the display area superimposed on the transmitted image visible through the optical element 753. Therefore, electronic devices 700A and 700B are electronic devices capable of AR display.

[0377] Electronic devices 700A and 700B may be equipped with cameras capable of capturing images of the area in front of them as imaging units. Furthermore, electronic devices 700A and 700B may each be equipped with acceleration sensors such as gyro sensors to detect the orientation of the user's head and display an image corresponding to that orientation in the display area 756.

[0378] The communications unit has a wireless communication device, which can supply, for example, a video signal. Alternatively, instead of the wireless communication device, or in addition to the wireless communication device, it may be equipped with a connector to which a cable for supplying video signals and power potential can be connected.

[0379] Furthermore, electronic devices 700A and 700B are equipped with batteries that can be charged wirelessly, wired, or both.

[0380] The housing 721 may be equipped with a touch sensor module. The touch sensor module has the function of detecting when the outer surface of the housing 721 is touched. The touch sensor module can detect the user's tap or slide operations and perform various processes. For example, a tap operation can be used to pause or resume the video, and a slide operation can be used to fast forward or rewind. Furthermore, by providing a touch sensor module in each of the two housings 721, the range of operations can be expanded.

[0381] Various types of touch sensors can be used in the touch sensor module. For example, various methods such as capacitive, resistive, infrared, electromagnetic induction, surface acoustic wave, or optical sensors can be employed. In particular, it is preferable to apply capacitive or optical sensors to the touch sensor module.

[0382] When using an optical touch sensor, a photoelectric conversion device (also called a photoelectric conversion element) can be used as the light-receiving element. The active layer of the photoelectric conversion device can be made of either an inorganic semiconductor or an organic semiconductor, or both.

[0383] An electronic device according to one aspect of the present invention may have a function for wireless communication with an earphone 750. The earphone 750 has a communication unit (not shown) and has a wireless communication function. The earphone 750 can receive information (e.g., voice data) from the electronic device through its wireless communication function. For example, the electronic device 700A shown in Figure 7(A) has a function for transmitting information to the earphone 750 through its wireless communication function.

[0384] Furthermore, the electronic device may have an earphone section. The electronic device 700B shown in Figure 7(B) has an earphone section 727. For example, the earphone section 727 and the control unit can be connected to each other by a wire. Part of the wiring connecting the earphone section 727 and the control unit may be located inside the housing 721 or the mounting section 723.

[0385] Furthermore, the electronic device may have an audio output terminal to which earphones or headphones can be connected. The electronic device may also have an audio input terminal and / or an audio input mechanism. For example, a microphone or other sound-collecting device can be used as the audio input mechanism. By having an audio input mechanism, the electronic device may be given the function of a so-called headset.

[0386] Furthermore, the electronic device according to one aspect of the present invention is not limited to the glasses type shown in electronic device 700A and electronic device 700B, but a goggle type is also equally suitable.

[0387] Furthermore, an electronic device according to one aspect of the present invention can transmit information to earphones via wired or wireless means.

[0388] The electronic device 6500 shown in Figure 8(A) is a portable information terminal that can be used as a smartphone.

[0389] The electronic device 6500 includes a housing 6501, a display unit 6502, a power button 6503, a button 6504, a speaker 6505, a microphone 6506, a camera 6507, and a light source 6508, etc. The display unit 6502 has a touch panel function.

[0390] A display device according to one embodiment of the present invention can be applied to the display unit 6502. Therefore, a highly reliable electronic device can be made.

[0391] Figure 8(B) is a schematic cross-sectional view of the housing 6501 including the end on the microphone 6506 side.

[0392] A light-transmitting protective member 6510 is provided on the display side of the housing 6501, and the display panel 6511, optical member 6512, touch sensor panel 6513, printed circuit board 6517, and battery 6518 are arranged in the space enclosed by the housing 6501 and the protective member 6510.

[0393] The protective member 6510 is fixed to the display panel 6511, the optical member 6512, and the touch sensor panel 6513 by an adhesive layer (not shown).

[0394] In the area outside the display unit 6502, a portion of the display panel 6511 is folded back, and the FPC 6515 is connected to this folded portion. IC 6516 is mounted on the FPC 6515. The FPC 6515 is connected to terminals provided on the printed circuit board 6517.

[0395] A display device according to one embodiment of the present invention can be applied to the display panel 6511. This makes it possible to realize an extremely lightweight electronic device. Furthermore, because the display panel 6511 is extremely thin, it is possible to incorporate a large-capacity battery 6518 while keeping the thickness of the electronic device low. In addition, by folding back a part of the display panel 6511 and placing the connection part with the FPC 6515 on the back of the pixel section, an electronic device with a narrow bezel can be realized.

[0396] Figure 8(C) shows an example of a television system. The television system 7100 has a display unit 7000 incorporated into a housing 7171. Here, the housing 7171 is shown supported by a stand 7173.

[0397] A display device according to one embodiment of the present invention can be applied to the display unit 7000. Therefore, a highly reliable electronic device can be made.

[0398] The television device 7100 shown in Figure 8(C) can be operated using the operation switches on the housing 7171 and a separate remote control unit 7151. Alternatively, the display unit 7000 may be equipped with a touch sensor, and the television device 7100 can be operated by touching the display unit 7000 with a finger or the like. The remote control unit 7151 may have a display unit that displays information output from the remote control unit 7151. Channels and volume can be controlled and the image displayed on the display unit 7000 can be controlled using the operation keys or touch panel on the remote control unit 7151.

[0399] The television system 7100 is configured to include a receiver and a modem. The receiver can receive general television broadcasts. Furthermore, 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.

[0400] Figure 8(D) shows an example of a notebook personal computer. The notebook personal computer 7200 has a casing 7211, a keyboard 7212, a pointing device 7213, and an external connection port 7214, etc. A display unit 7000 is incorporated into the casing 7211.

[0401] A display device according to one embodiment of the present invention can be applied to the display unit 7000. Therefore, a highly reliable electronic device can be made.

[0402] Figures 8(E) and 8(F) show examples of digital signage that can be used in shop windows and display cases.

[0403] The digital signage 7300 shown in Figure 8(E) comprises a housing 7301, a display unit 7000, and a speaker 7303, etc. Furthermore, it may have LED lamps, operation keys (including a power switch or operation switch), connection terminals, various sensors, a microphone, etc.

[0404] Figure 8(F) shows a digital signage 7400 mounted on a cylindrical column 7401. The digital signage 7400 has a display unit 7000 that is provided along the curved surface of the column 7401.

[0405] In Figures 8(E) and 8(F), a display device according to one embodiment of the present invention can be applied to the display unit 7000. Therefore, a highly reliable electronic device can be made.

[0406] The larger the display area 7000, the more information can be provided at once. Furthermore, a larger display area 7000 is more eye-catching, which can, for example, enhance the effectiveness of advertising.

[0407] In particular, when using a display device according to one aspect of the present invention for advertising using the digital signage 7300 and digital signage 7400 shown in Figures 8(E) and 8(F), the degree of freedom of expression can be increased by using a light-transmitting panel. For example, a light-transmitting display device can be manufactured by using wiring and support members made of a conductive film that transmits visible light and adjusting the distance between pixel electrodes.

[0408] Furthermore, by using a tandem-structured light-emitting device, which is one aspect of the present invention, in addition to the wiring and support members using the conductive film that transmits visible light, it is possible to increase the brightness per pixel. In other words, good display is possible even with a small aperture ratio of the display device, thus increasing the light transmittance of the display section of the display device. Therefore, such a configuration is suitable as a light-transmitting display device, which is one aspect of the present invention.

[0409] Furthermore, as shown in Figures 8(E) and 8(F), it is preferable that the digital signage 7300 or digital signage 7400 can be linked wirelessly with an information terminal 7311 or information terminal 7411 such as a smartphone owned by the user. For example, the advertising information displayed on the display unit 7000 can be displayed on the screen of the information terminal 7311 or information terminal 7411. Also, the display on the display unit 7000 can be switched by operating the information terminal 7311 or information terminal 7411.

[0410] Furthermore, the digital signage 7300 or digital signage 7400 can be used to run games using the screen of the information terminal 7311 or information terminal 7411 as the control device (controller). This allows an unspecified number of users to participate in and enjoy the game simultaneously.

[0411] The electronic equipment shown in Figures 9(A) to 9(G) includes a housing 9000, a display unit 9001, a speaker 9003, operation keys 9005 (including a power switch or operation switch), connection terminals 9006, sensors 9007 (including functions for measuring force, displacement, position, velocity, acceleration, angular velocity, rotational speed, distance, light, liquid, magnetism, temperature, chemical substances, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared radiation), a microphone 9008, etc.

[0412] The electronic devices shown in Figures 9(A) to 9(G) have various functions. For example, they may have functions 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 or time, a function to control processing by various software (programs), a wireless communication function, a function to read and process programs or data recorded on a recording medium, etc. However, the functions of electronic devices are not limited to these and can have various functions. Electronic devices may have multiple display units. Furthermore, electronic devices may be equipped with a camera, etc., and have functions to capture still images or videos and save them to a recording medium (external or built into the camera), a function to display the captured images on a display unit, etc.

[0413] Details of the electronic equipment shown in Figures 9(A) to 9(G) will be explained below.

[0414] Figure 9(A) is a perspective view showing a personal digital assistant (PDA) 9171. The PDA 9171 can be used, for example, as a smartphone. The PDA 9171 may also be equipped with a speaker 9003, a connection terminal 9006, or a sensor 9007. The PDA 9171 can also display text and image information on multiple surfaces. Figure 9(A) shows an example where three icons 9050 are displayed. Information 9051, indicated by a dashed rectangle, can also be displayed on other surfaces of the display unit 9001. Examples of information 9051 include notifications of incoming emails, SNS messages, phone calls, etc., the subject of an email or SNS message, the sender's name, date and time, battery level, signal strength, etc. Alternatively, icons 9050, etc., may be displayed in the location where the information 9051 is displayed.

[0415] Figure 9(B) is a perspective view showing the personal digital assistant (PDA) 9172. The PDA 9172 has the function of displaying information on three or more sides of the display unit 9001. Here, an example is shown in which information 9052, information 9053, and information 9054 are displayed on different sides. For example, a user can check information 9053, which is displayed in a position that can be observed from above the PDA 9172, while the PDA 9172 is stored in the breast pocket of their clothing. The user can check the display without taking the PDA 9172 out of their pocket and decide, for example, whether or not to answer a call.

[0416] Figure 9(C) is a perspective view showing the tablet terminal 9173. The tablet terminal 9173 can run various applications, such as mobile phone calls, email, document viewing and creation, music playback, internet communication, and computer games. The tablet terminal 9173 has a display unit 9001, a camera 9002, a microphone 9008, and a speaker 9003 on the front of the housing 9000. The left side of the housing 9000 has operation keys 9005 as buttons for operation, and the bottom has connection terminals 9006.

[0417] Figure 9(D) is a perspective view showing a wristwatch-type personal information terminal 9200. The personal information terminal 9200 can be used, for example, as a smartwatch (registered trademark). The personal information terminal 9200 may have an operation key 9005 as an operation button on the left side of the housing 9000 and a sensor 9007 on the bottom. As an example, a curved bangle-type housing 9000 is shown, but the housing 9000 may be structured to allow attachment of a belt or the like. The display unit 9001 has a curved display surface and can display along the curved surface. The power storage device 9004 may also have a curved shape that follows the housing 9000. The power storage device 9004 is also flexible and can be bent according to the change in shape when attached or detached. It may also have a charging control IC connected to the power storage device 9004. The personal information terminal 9200 can also make hands-free calls by communicating with, for example, a wireless communication headset. Furthermore, the portable information terminal 9200 can wirelessly transmit data to and from other information terminals, and can also be charged wirelessly. Alternatively, data transmission and charging may be performed via wired connections using a connection terminal 9006 provided on the housing 9000.

[0418] Figures 9(E) to 9(G) are perspective views showing a foldable personal information terminal 9201. Figure 9(E) shows the personal information terminal 9201 in an unfolded state, Figure 9(G) shows it in a folded state, and Figure 9(F) shows a state in between, transitioning from one of Figures 9(E) or 9(G) to the other. The personal information terminal 9201 offers excellent portability in its folded state and excellent readability of the display due to its seamless, wide display area in its unfolded state. The display unit 9001 of the personal information terminal 9201 is supported by three housings 9000 connected by hinges 9055. For example, the display unit 9001 can be bent with a radius of curvature of 0.1 mm to 150 mm.

[0419] This embodiment can be appropriately combined with other embodiments or examples. Furthermore, if multiple configuration examples are shown within a single embodiment in this specification, these configuration examples can be appropriately combined. [Examples]

[0420] <<Synthesis Example 1>> This synthesis example shows the synthesis method and properties of 2-(3-(2,6-dimethylpyridine-3-yl)-{[3',5'-bis(trimethylsilyl)]biphenyl}-5-yl)-4,6-diphenyl-1,3,5-triazine (abbreviation: mmTMSPh-mDMePyPTzn) (structural formula (100)), an organic compound according to one aspect of the present invention.

[0421] [ka]

[0422] <Step 1: Synthesis of 2-[3-(2,6-dimethylpyridine-3-yl)-5-(4,6-diphenyl-1,3,5-triazine)]phenyl-4,4,5,5-tetramethyl-1,3,2-dioxaborolane> 7.0 g (16 mmol) of 2-[3-chloro-5-(2,6-dimethylpyridine-3-yl)phenyl]-4,6-diphenyl-1,3,5-triazine, 5.9 g (23 mmol) of bis(pinacollate)diborone, 4.2 g (43 mmol) of potassium acetate, and 230 mL of 1,4-dioxane were added to a three-necked flask and the mixture was stirred under reduced pressure to degass it. After degassing, 0.14 g (0.28 mmol) of 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl (abbreviation: XPhos) and 32 mg (0.14 mmol) of palladium(II) acetate were added and the mixture was stirred at 100°C for 14 hours. After the reaction was complete, water was added to the resulting reaction mixture to separate it into an organic layer and an aqueous layer. Toluene was added to the aqueous layer for extraction. The toluene layer and the organic layer were mixed, and magnesium sulfate was added to adsorb the water. The mixture was filtered naturally, and the resulting filtrate was concentrated to obtain a pale yellow solid. This solid was purified by silica gel column chromatography using toluene:ethyl acetate in a ratio of 10:1 to 3:1. The resulting solution was concentrated to obtain 8.1 g of the desired pale yellow solid (yield: 96%). The synthesis scheme for Step 1 is shown in formula (a-1) below.

[0423] [ka]

[0424] Nuclear magnetic resonance spectroscopy of the pale yellow solid obtained in step 1 above ( 1 The results of the analysis by 1H-NMR are shown below. 1 Figure 13 shows the 1H-NMR chart, and Figure 14 shows a magnified view of the range from 6.5 ppm to 9.5 ppm in Figure 13. Note that the singlet peak around 2.36 ppm and the multiplet peak around 7.17 to 7.25 ppm are peaks originating from toluene, which was used as the purification solvent.

[0425] 1H-NMR.δ(CDCl3,300MHz):1.42(s,12H), 2.57(s,3H), 2.62(s,3H), 7.11(d,1H,J=7 .5Hz), 7.54-7.63(m,7H), 7.99-8.00(m,1H), 8.77-8.82(m,5H), 9.13-9.14(m,1H).

[0426] <Step 2: Synthesis of mmTMSPh-mDMePyPTzn> In a three-necked flask, 1.3 g (2.4 mmol) of 2-[3-(2,6-dimethylpyridine-3-yl)-5-(4,6-diphenyl-1,3,5-triazine)]phenyl-4,4,5,5-tetramethyl-1,3,2-dioxaborolane obtained in Step 1, 0.66 g (2.2 mmol) of 3,5-bis(trimethylsilyl)bromobenzene, 0.60 g (4.4 mmol) of potassium carbonate, 25 mL of toluene, 5 mL of ethanol, and 3 mL of water were added, and the mixture was stirred under reduced pressure to degass it. After degassing, 90 mg (0.22 mmol) of 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl (SPhos) and 9.8 mg (48 μmol) of palladium(II) acetate were added, and the mixture was reacted at 80°C for 14 hours. After the reaction was complete, the reaction mixture was separated into an organic layer and an aqueous layer. The obtained aqueous layer was extracted with toluene and mixed with the obtained organic layer. Magnesium sulfate was added to adsorb water. The mixture was filtered naturally, and the resulting filtrate was concentrated to obtain a yellow solid. This solid was purified by silica gel column chromatography with the developing solvent varied from toluene:ethyl acetate = 30:1 to 20:1 to obtain 1.19 g of pale yellow solid. This solid was recrystallized with toluene / ethanol to obtain 0.88 g of the target white solid (yield: 58%). 0.87 g of the obtained solid was purified by sublimation using the train sublimation method. The sublimation purification conditions were heating the solid at a pressure of 5.8 Pa and 235 °C for 18 hours. After sublimation purification, 0.77 g of the target white solid (yield: 89%) was obtained. The synthesis scheme for Step 2 is shown below (a-2).

[0427] [ka]

[0428] Nuclear magnetic resonance spectroscopy of the white solid obtained in step 2 above ( 1 The results of the analysis by 1H-NMR are shown below. 1 Figure 15 shows the 1H-NMR chart, and Figure 16 shows a magnified view of the range from 6.5 ppm to 9.5 ppm in Figure 15. From these results, it was found that in this synthesis example, the organic compound mmTMSPh-mDMePyPTzn, which is one embodiment of the present invention, was obtained.

[0429] 1 H-NMR.δ(CDCl3,300MHz):0.37(s,18H), 2.63(s,3H), 2.65(s,3H), 7.17(d,1H,J=8.1Hz), 7.55-7.65(m,7H) , 7.75-7.76(m,2H), 7.88(d,2H,J=0.9Hz), 8.69(t,1H,J=1.5Hz), 8.77-8.80(m,4H), 9.04(t,1H,J=1.7Hz).

[0430] <Emission and absorption spectrum measurement> Next, Figure 17 shows the absorption and emission spectra of a dichloromethane solution of mmTMSPh-mDMePyPTzn. Figure 18 shows the absorption and emission spectra of a thin film of mmTMSPh-mDMePyPTzn. The thin film was fabricated on a quartz substrate by vacuum deposition. The absorption spectrum of the dichloromethane solution was measured using a UV-Vis spectrophotometer (JASCO V-770DS), and the spectrum measured with only dichloromethane in a quartz cell was subtracted. The absorption spectrum of the thin film was measured using a spectrophotometer (Hitachi High-Technologies Corporation U4100). The emission spectrum was measured using a fluorometer (JASCO FP-8600).

[0431] As shown in Fig. 17, the dichloromethane solution of mmTMSPh-mDMePyPTzn showed a peak at a wavelength of 270 nm in the absorption spectrum and a peak at a wavelength of 390 nm (excitation wavelength 270 nm) in the emission spectrum. Also, as shown in Fig. 18, the thin film of mmTMSPh-mDMePyPTzn showed a peak at a wavelength of 265 nm in the absorption spectrum and a peak at a wavelength of 390 nm (excitation wavelength 310 nm) in the emission spectrum. From Figs. 17 and 18, it was found that mmTMSPh-mDMePyPTzn did not show absorption in the visible region (longer wavelength side than 450 nm).

[0432] <Measurement of refractive index> Fig. 19 shows the results of measuring the refractive index of the film of mmTMSPh-mDMePyPTzn using a spectroscopic ellipsometer (M-2000U manufactured by J. A. Woollam Japan Co., Ltd.). For the measurement, a film formed by vacuum evaporation of the material on a quartz substrate to a film thickness of 50 nm was used. In the figure, the refractive index of the ordinary ray, n, Ordinary, and the refractive index of the extraordinary ray, n, Extra-ordinary, are described.

[0433] From Fig. 19, it was found that the film of mmTMSPh-mDMePyPTzn had an ordinary refractive index in the range of 1.50 or more and 1.75 or less throughout the blue light emission region (wavelength of 455 nm or more and 465 nm or less), and also the ordinary refractive index at a wavelength of 633 nm was in the range of 1.45 or more and 1.70 or less, indicating that it was a film with a low refractive index.

[0434] <Measurement of GSP_slope> Next, the GSP_slope of the vapor-deposited film of mmTMSPh-mDMePyPTzn was measured. The measurement was performed using the method shown in Embodiment 1. The results are shown in Table 3. For comparison, Table 3 also shows the GSP_slope of the vapor-deposited film of 2-{3-(2,6-dimethylpyridine-3-yl)-5-[(3,5-di-tert-butyl)phenyl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: mmtBuPh-mDMePyPTzn). The chemical formula of mmTMSPh-mDMePyPTzn, an organic compound according to one embodiment of the present invention, and the chemical formula of mmtBuPh-mDMePyPTzn, an organic compound for comparison, are shown below.

[0435] [ka]

[0436] [Table 3]

[0437] As shown in Table 3, mmTMSPh-mDMePyPTzn, an organic compound according to one embodiment of the present invention, had a smaller GSP_slope of film than mmtBuPh-mDMePyPTzn, a comparative organic compound. mmTMSPh-mDMePyPTzn has a trisubstituted silyl group in which the quaternary carbon atoms of the two tert-butyl groups of mmtBuPh-mDMePyPTzn are each replaced with silicon atoms. Since silicon atoms have lower electronegativity compared to carbon atoms, mmTMSPh-mDMePyPTzn has a smaller permanent electric dipole moment than mmtBuPh-mDMePyPTzn, and it can be considered that the SOP in the deposited film was smaller, resulting in a smaller GSP_slope.

[0438] <Calculation of Permanent Electric Dipole Moment> Next, the permanent electric dipole moment was analyzed for the stable singlet ground state structure of mmTMSPh-mDMePyPTzn, an organic compound according to one embodiment of the present invention, and mmtBuPh-mDMePyPTzn, a comparative organic compound.

[0439] The calculation method used was Density Functional Theory (DFT). The functional used was B3LYP, and the basis function was 6-311G(d,p). Gaussian16 was used as the calculation program.

[0440] The stable structure of mmTMSPh-mDMePyPTzn used in the calculation is shown in Figure 20(A). Furthermore, a view of the same stable structure from the y-axis direction is shown in Figure 20(B), and a view from the x-axis direction is shown in Figure 20(C). The stable structure of mmtBuPh-mDMePyPTzn used in the calculation is also shown in Figure 21(A). Furthermore, a view of the same stable structure from the y-axis direction is shown in Figure 21(B), and a view from the x-axis direction is shown in Figure 21(C). As can be seen from Figures 20(A) to 21(C), the stable structure of mmTMSPh-mDMePyPTzn used in this calculation and the stable structure of mmtBuPh-mDMePyPTzn have similar conformations. In other words, the stable structure was calculated assuming that the initial structure had the same conformation, except for the trimethylsilyl group and the tert-butyl group. This ensured that the comparison was not based on differences in the conformation of the groups other than the trimethylsilyl group and the tert-butyl group.

[0441] Table 4 shows the magnitudes of the permanent electric dipole moments of mmTMSPh-mDMePyPTzn and mmtBuPh-mDMePyPTzn, which were calculated.

[0442] [Table 4]

[0443] Table 4 confirms that mmTMSPh-mDMePyPTzn has a smaller permanent electric dipole moment than mmtBuPh-mDMePyPTzn. Furthermore, it was confirmed that the same trend is observed when comparing the permanent electric dipole moments of mmTMSPh-mDMePyPTzn and mmtBuPh-mDMePyPTzn with similar conformations, but with different conformations of the stable structures of each substituent as shown in Figures 20 and 21. For example, when comparing the stable structure of mmTMSPh-mDMePyPTzn shown in Figure 20(A), in which the dimethylpyridinyl group is rotated 180° around the bond between the dimethylpyridinyl group and the benzene ring to which it is bonded, with the stable structure of mmtBuPh-mDMePyPTzn shown in Figure 21(A), in which the dimethylpyridinyl group is rotated 180°, mmTMSPh-mDMePyPTzn had a smaller permanent electric dipole moment than mmtBuPh-mDMePyPTzn.

[0444] From the above results, it was found that the reason why the GSP_slope of the mmTMSPh-mDMePyPTzn vapor-deposited film is smaller than that of the mmtBuPh-mDMePyPTzn vapor-deposited film is because mmTMSPh-mDMePyPTzn has a smaller permanent electric dipole moment than mmtBuPh-mDMePyPTzn. Therefore, it was found that the GSP_slope of the vapor-deposited film can be reduced by introducing a trisubstituted silyl group, in which the quaternary carbon atoms of the tert-butyl group are replaced with silicon atoms, into the organic compound instead of the tert-butyl group. [Examples]

[0445] In this example, we fabricated light-emitting devices G-1 and G-4 using the organic compound mmTMSPh-mDMePyPTzn, one embodiment of the present invention whose synthesis method was described in Example 1, and comparative light-emitting devices G-2, G-3, and G-5 using comparative organic compounds, and describe the results of measuring the characteristics of each device. These light-emitting devices exhibit green phosphorescence. The structural formulas of the organic compounds used in each light-emitting device are shown below.

[0446] [ka]

[0447] As shown in Figure 11, each light-emitting device has a structure in which a hole injection layer 911, a hole transport layer 912, a light-emitting layer 913, an electron transport layer (a first electron transport layer 914_1 and a second electron transport layer 914_2), and an electron injection layer 915 are sequentially stacked on a first electrode 901 formed on a glass substrate 900, and a second electrode 902 is stacked on the electron injection layer 915.

[0448] <Method for fabricating the light-emitting device G-1> A first electrode 901 was formed on a glass substrate 900 by sputtering a film of indium tin oxide (ITSO) containing silicon oxide to a thickness of 70 nm. The electrode area was 4 mm². 2 (2mm x 2mm)

[0449] Next, as a pretreatment for forming the light-emitting device on the substrate, the substrate surface was washed with water and fired at 200°C for 1 hour. After that, 1 × 10 -4 The substrate was introduced into a vacuum deposition apparatus where the internal pressure was reduced to approximately Pa, and vacuum firing was performed at 170°C for 30 minutes in the heating chamber within the vacuum deposition apparatus. After that, it was allowed to cool naturally.

[0450] Next, the substrate on which the first electrode 901 is formed is fixed to a substrate holder provided in a vacuum deposition apparatus so that the surface on which the first electrode 901 is formed faces downwards. Then, N-(biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-9,9-dimethyl-9H-fluoren-2-amine (abbreviated as PCBBiF) and an electron acceptor material (OCHD-003) containing fluorine with a molecular weight of 672 are co-deposited on the first electrode 901 in a weight ratio of 1:0.03 (=PCBBiF:OCHD-003) and with a film thickness of 10 nm to form a hole injection layer 911.

[0451] Next, a hole transport layer 912 was formed by depositing PCBBiF onto the hole injection layer 911 to a thickness of 40 nm.

[0452] Next, on the hole transport layer 912, 8-(p-terphenyl-3-yl)-4-[3-(dibenzothiophen-4-yl)phenyl]-[1]benzoflo[3,2-d]pyrimidine (abbreviated as 8mpTP-4mDBtPBfpm), 9-(2-naphthyl)-9'-phenyl-3,3'-bi-9H-carbazole (abbreviated as βNCCP), and [2-d3-methyl-8-(2-pyridinyl-κN)benzoflo[2,3-b]pyrimidine are placed. A light-emitting layer 913 was formed by co-depositing din-κC]bis[2-(5-d3-methyl-2-pyridinyl-κN2)phenyl-κC]iridium(III) (abbreviation: Ir(5mppy-d3)2(mbfpypy-d3)) in a weight ratio of 0.5:0.5:0.1 (=8mpTP-4mDBtPBfpm:βNCCP:Ir(5mppy-d3)2(mbfpypy-d3)) and with a film thickness of 40 nm.

[0453] Next, a first electron transport layer 914_1 was formed on the light-emitting layer 913 by depositing 2-{3-[3-(N-phenyl-9H-carbazole-3-yl)-9H-carbazole-9-yl]phenyl}dibenzo[f,h]quinoxaline (abbreviated as 2mPCCzPDBq) to a thickness of 20 nm. Subsequently, a second electron transport layer 914_2 was formed by co-depositing mmTMSPh-mDMePyPTzn, an organic compound according to one aspect of the present invention, and 8-quinolinolato-lithium (abbreviated as Liq) in a weight ratio of 1:1 (=mmTMSPh-mDMePyPTzn:Liq) and to a thickness of 20 nm.

[0454] Next, an electron injection layer 915 was formed on the second electron transport layer 914_2 by depositing lithium fluoride (LiF) to a thickness of 1 nm.

[0455] Next, a second electrode 902 was formed on the electron injection layer 915 by depositing aluminum (Al) to a thickness of 100 nm, thereby fabricating the light-emitting device G-1.

[0456] <Method for fabricating the comparative light-emitting device G-2> Comparative light-emitting device G-2 differs from light-emitting device G-1 in that it replaces mmTMSPh-mDMePyPTzn, an organic compound according to one embodiment of the present invention used in the second electron transport layer 914_2 of light-emitting device G-1, with mmtBuPh-mDMePyPTzn, a comparative organic compound. The other components were fabricated in the same manner as light-emitting device G-1.

[0457] <Method for fabricating the comparative light-emitting device G-3> Comparative light-emitting device G-3 differs from light-emitting device G-1 in that it forms a second electron transport layer 914_2 by depositing the comparative organic compound 2,2'-(1,3-phenylene)bis(9-phenyl-1,10-phenanthroline) (abbreviated as mPPhen2P) to a thickness of 20 nm. The other components were fabricated in the same manner as light-emitting device G-1.

[0458] <Method for fabricating the light-emitting device G-4> Light-emitting device G-4 differs from light-emitting device G-1 in that it forms a first electron transport layer 914_1 by depositing mmTMSPh-mDMePyPTzn, an organic compound according to one aspect of the present invention, to a thickness of 20 nm, and forms a second electron transport layer 914_2 by co-depositing 2-[3-(2,6-dimethyl-3-pyridinyl)-5-(9-phenanthryl)phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviated as mPn-mDMePyPTzn) and Liq in a weight ratio of 1:1 (=mPn-mDMePyPTzn:Liq) to a thickness of 20 nm. The other components were fabricated in the same manner as light-emitting device G-1.

[0459] <Method for fabricating the comparative light-emitting device G-5> Comparative light-emitting device G-5 differs from light-emitting device G-4 in that it replaces mmTMSPh-mDMePyPTzn, an organic compound according to one aspect of the present invention used in the first electron transport layer 914_1 of light-emitting device G-4, with 2mPCCzPDBq, a comparative organic compound. The other components were fabricated in the same manner as light-emitting device G-4.

[0460] Table 5 summarizes the device structures of light-emitting device G-1, comparative light-emitting device G-2, and comparative light-emitting device G-3. Table 6 summarizes the device structures of light-emitting device G-4 and comparative light-emitting device G-5.

[0461] [Table 5]

[0462] [Table 6]

[0463] <Light-emitting device characteristics> The above-mentioned light-emitting device was sealed with a glass substrate in a glove box under a nitrogen atmosphere to prevent exposure to the atmosphere (sealing material was applied around the element, UV treatment was performed during sealing, and heat treatment was performed at 80°C for 1 hour). After this, the characteristics of the light-emitting device were measured.

[0464] Figure 24 shows the luminance-current density characteristics of light-emitting device G-1, comparative light-emitting device G-2, and comparative light-emitting device G-3, Figure 25 shows the luminance-voltage characteristics, Figure 26 shows the current efficiency-luminance characteristics, Figure 28 shows the external quantum efficiency-luminance characteristics, and Figure 29 shows the field emission spectra. In addition, Figure 27 shows the current density-voltage characteristics of light-emitting device G-1 and comparative light-emitting device G-2, and Figure 30 shows the capacitance-voltage characteristics. Furthermore, light-emitting device G-1, comparative light-emitting device G-2, and comparative light-emitting device G-3 are subjected to 2mA (50mA / cm²). 2 Figure 31 shows the change in brightness with respect to driving time when a constant current is applied and the device is driven. Figure 32 shows the brightness-current density characteristics of light-emitting device G-4 and comparative light-emitting device G-5, Figure 33 shows the brightness-voltage characteristics, Figure 34 shows the current efficiency-brightness characteristics, Figure 35 shows the current density-voltage characteristics, Figure 36 shows the external quantum efficiency-brightness characteristics, and Figure 37 shows the field emission spectra. In the legend of Figures 24 to 37, light-emitting device G-1, comparative light-emitting device G-2, comparative light-emitting device G-3, light-emitting device G-4, and comparative light-emitting device G-5 are denoted as Device G-1, Comp. device G-2, Comp. device G-3, Device G-4, and Comp. device G-5, respectively.

[0465] Furthermore, the brightness of each light-emitting device is 1000 cd / m². 2 Table 7 shows the main characteristics of the vicinity. A spectroradiometer (Topcon SR-UL1R) was used to measure luminance, CIE chromaticity, and emission spectrum. The external quantum efficiency was calculated using the luminance and emission spectrum measured with the spectroradiometer, assuming that the light distribution characteristics were Lambertsian.

[0466] [Table 7]

[0467] Figures 24 to 37 and Table 7 clearly show that light-emitting devices G-1 and G-4 are light-emitting devices with good characteristics, exhibiting green light emission originating from Ir(5mppy-d3)2(mbfpypy-d3).

[0468] Figures 25 and 27 show that the light-emitting device G-1 has a lower drive voltage than the comparative light-emitting device G-2 at low brightness or low current density. Furthermore, Figures 26 and 28 show that the light-emitting device G-1 has a higher luminous efficiency than the comparative light-emitting device G-3.

[0469] Furthermore, as shown in Figure 30, the light-emitting device G-1 is V inj It was found that V was low. inj This represents the voltage required to inject electrons from the electron injection layer 915 or the second electrode 902 into the second electron transport layer 914_2. Therefore, it was found that the light-emitting device G-1 can inject electrons into the second electron transport layer 914_2 at a lower voltage than the comparative light-emitting device G-2.

[0470] Furthermore, Figure 31 shows that the light-emitting device G-1 exhibits a brightness change with respect to operating time that is equivalent to that of comparative light-emitting devices G-2 and G-3, indicating that it is a long-life light-emitting device.

[0471] Furthermore, Figures 33 and 35 show that the light-emitting device G-4 has a lower drive voltage than the comparative light-emitting device G-5. Also, Figures 34 and 36 show that the light-emitting device G-4 has a higher luminous efficiency than the comparative light-emitting device G-5.

[0472] Here, the ordinary refractive index (n) of the vapor-deposited films of the main organic compounds used in each light-emitting device. oTable 8 shows the GSP_slope for each organic compound film. In Table 8, the ordinary refractive index is shown at a wavelength of 633 nm. A spectroscopic ellipsometer (M-2000U, manufactured by J.A. Woolam Japan Co., Ltd.) was used to measure the ordinary refractive index, and the sample used for measurement was a film in which each layer material was deposited on a quartz substrate by vacuum deposition to a thickness of 50 nm. In addition, in Table 8, the GSP_slope of each organic compound film was measured by the method shown in Embodiment 1.

[0473] [Table 8]

[0474] As shown in Table 8, mmTMSPh-mDMePyPTzn, an organic compound according to one embodiment of the present invention, is an organic compound that has a lower refractive index than mPPhen2P and 2mPCCzPDBq, and a smaller GSP_slope than mmtBuPh-mDMePyPTzn.

[0475] As mentioned above, the light-emitting device G-1 has a higher V rating than the comparative light-emitting device G-2. inj It was found that electrons could be injected into the second electron transport layer 914_2 at a lower voltage than the comparative light-emitting device G-2. Furthermore, it was found that the light-emitting device G-1 had a lower drive voltage than the comparative light-emitting device G-2 at low brightness or low current density. These results can be explained by the fact that the mmTMSPh-mDMePyPTzn used in the light-emitting device G-1 has a smaller film GSP_slope than the mmtBuPh-mDMePyPTzn used in the comparative light-emitting device G-2, as shown in Table 6. In other words, by using mmTMSPh-mDMePyPTzn with a smaller film GSP_slope for the second electron transport layer 914_2 in the light-emitting device G-1, electrons could be injected into the second electron transport layer 914_2 at a lower voltage. Moreover, because electrons could be injected into the second electron transport layer 914_2 at a lower voltage, the drive voltage of the light-emitting device could be reduced.

[0476] From the above results, it was found that the light-emitting device using the organic compound according to one embodiment of the present invention is a light-emitting device with a low driving voltage and high luminous efficiency. This is because the organic compound according to one embodiment of the present invention is an organic compound with a low refractive index and a small GSP_slope of the film. By using the organic compound according to one embodiment of the present invention in the electron transport layer, the light extraction efficiency from the light-emitting layer in the light-emitting device is improved, and it becomes possible to apply voltage to the light-emitting layer effectively.

[0477] Furthermore, the organic compound according to one embodiment of the present invention has a smaller GSP_slope of film and V in the second electron transport layer of the light-emitting device. inj Because the coefficient of emission can be lowered, the range of material selection for the first electron transport layer 914_1 and the light-emitting layer 913 in a light-emitting device using an organic compound according to one aspect of the present invention is broadened. Therefore, it has been found that the organic compound according to one aspect of the present invention can be suitably used in light-emitting devices of various configurations. Furthermore, it has been found that the organic compound according to one aspect of the present invention is easily used in a carrier transport layer in a display device that uses a carrier transport layer common to multiple pixels with different light emission colors. [Examples]

[0478] In this example, light-emitting devices B-1 and B-3, which use the organic compound mmTMSPh-mDMePyPTzn according to one embodiment of the present invention whose synthesis method was described in Example 1, and comparative light-emitting devices B-2, B-4 to B-6, which use comparative organic compounds, were fabricated, and the results of measuring the characteristics of each device are described. These light-emitting devices are light-emitting devices that exhibit blue fluorescence emission. The structural formulas of the organic compounds used in each light-emitting device are shown below.

[0479] [ka]

[0480] As shown in Figure 12, each light-emitting device has a structure in which a hole injection layer 911, a hole transport layer (first hole transport layer 912_1 and second hole transport layer 912_2), a light-emitting layer 913, an electron transport layer (first electron transport layer 914_1 and second electron transport layer 914_2), and an electron injection layer 915 are sequentially stacked on a first electrode 901 formed on a glass substrate 900.

[0481] <Method for fabricating light-emitting device B-1> A first electrode 901 was formed on a glass substrate 900 by sputtering a film of indium tin oxide (ITSO) containing silicon oxide to a thickness of 55 nm. The electrode area was 4 mm². 2 (2mm x 2mm)

[0482] Next, pre-treatment and vacuum firing were performed to form the light-emitting device on the substrate, similar to the method for fabricating the light-emitting device G-1 shown in Example 2. After that, it was allowed to cool naturally.

[0483] Next, similar to the method for fabricating the light-emitting device G-1 shown in Example 2, a hole injection layer 911 was formed, and then a first hole transport layer 912_1 was formed by depositing PCBBiF to a thickness of 25 nm on the hole injection layer 911. Then, a second hole transport layer 912_2 was formed by depositing N,N-bis[4-(dibenzofuran-4-yl)phenyl]-4-amino-p-terphenyl (abbreviated as DBfBB1TP) to a thickness of 10 nm.

[0484] Next, a light-emitting layer 913 was formed by co-depositing 9-(1-naphthyl)-10-[4-(2-naphthyl)phenyl]anthracene (abbreviated as αN-βNPAnth) and N,N'-diphenyl-N,N'-bis(9-phenyl-9H-carbazole-2-yl)naphtho[2,3-b;6,7-b']bisbenzofuran-3,10-diamine (abbreviated as 3,10PCA2Nbf(IV)-02) on the second hole transport layer 912_2 in a weight ratio of 1:0.015 (=αN-βNPAnth:3,10PCA2Nbf(IV)-02) and with a film thickness of 25 nm.

[0485] Next, a first electron transport layer 914_1 was formed on the light-emitting layer 913 by depositing 2mPCCzPDBq to a thickness of 10 nm. Subsequently, a second electron transport layer 914_2 was formed by co-depositing mmTMSPh-mDMePyPTzn, an organic compound according to one aspect of the present invention, and Liq in a weight ratio of 1:1 (=mmTMSPh-mDMePyPTzn:Liq) and to a thickness of 20 nm.

[0486] Next, the electron injection layer 915 and the second electrode 902 were formed in the same manner as the method for fabricating the light-emitting device G-1 shown in Example 2.

[0487] <Method for fabricating comparative light-emitting device B-2> Comparative light-emitting device B-2 differs from light-emitting device B-1 in that it replaces mmTMSPh-mDMePyPTzn, an organic compound according to one embodiment of the present invention used in the second electron transport layer 914_2 of light-emitting device B-1, with mmtBuPh-mDMePyPTzn, a comparative organic compound. The other components were fabricated in the same manner as light-emitting device B-1.

[0488] <Method for fabricating light-emitting device B-3> Light-emitting device B-3 differs from light-emitting device B-1 in that it forms a first electron transport layer 914_1 by depositing mmTMSPh-mDMePyPTzn, an organic compound according to one aspect of the present invention, to a thickness of 10 nm, and forms a second electron transport layer 914_2 by co-depositing mPn-mDMePyPTzn and Liq in a weight ratio of 1:1 (=mPn-mDMePyPTzn:Liq) and to a thickness of 20 nm. The other components were fabricated in the same manner as light-emitting device B-1.

[0489] <Method for fabricating comparative light-emitting device B-4> Comparative light-emitting device B-4 differs from light-emitting device B-3 in that it replaces mmTMSPh-mDMePyPTzn, an organic compound according to one aspect of the present invention used in the first electron transport layer 914_1 of light-emitting device B-3, with mmtBuPh-mDMePyPTzn, a comparative organic compound. The other components were fabricated in the same manner as light-emitting device B-3.

[0490] <Method for fabricating comparative light-emitting device B-5> Comparative light-emitting device B-5 differs from light-emitting device B-3 in that mmTMSPh-mDMePyPTzn, an organic compound according to one aspect of the present invention used in the first electron transport layer 914_1 of light-emitting device B-3, is replaced with a comparative organic compound, 6-(biphenyl-3-yl)-4-[3,5-bis(9H-carbazole-9-yl)phenyl]-2-phenylpyrimidine (abbreviated as 6mBP-4Cz2PPm). The other components were fabricated in the same manner as light-emitting device B-3.

[0491] <Method for fabricating comparative light-emitting device B-6> Comparative light-emitting device B-6 differs from light-emitting device B-3 in that it replaces mmTMSPh-mDMePyPTzn, an organic compound according to one aspect of the present invention used in the first electron transport layer 914_1 of light-emitting device B-3, with 2mPCCzPDBq, a comparative organic compound. The other components were fabricated in the same manner as light-emitting device B-3.

[0492] Table 9 summarizes the device structures of light-emitting device B-1 and comparative light-emitting device B-2. Table 10 summarizes the device structures of light-emitting device B-3 and comparative light-emitting devices B-4 through B-6.

[0493] [Table 9]

[0494] [Table 10]

[0495] <Light-emitting device characteristics> The above-mentioned light-emitting device was sealed with a glass substrate in a glove box under a nitrogen atmosphere to prevent exposure to the atmosphere (sealing material was applied around the element, UV treatment was performed during sealing, and heat treatment was performed at 80°C for 1 hour). After this, the characteristics of the light-emitting device were measured.

[0496] Figure 38 shows the luminance-current density characteristics of light-emitting device B-1 and comparative light-emitting device B-2, Figure 39 shows the luminance-voltage characteristics, Figure 40 shows the current efficiency-luminance characteristics, Figure 41 shows the current density-voltage characteristics, Figure 42 shows the external quantum efficiency-luminance characteristics, Figure 43 shows the blue index-luminance characteristics, and Figure 44 shows the electroluminescence spectra. In addition, light-emitting device B-1 and comparative light-emitting device B-2 were subjected to 2mA (50mA / cm²). 2 Figure 45 shows the change in brightness with respect to the driving time when a constant current is applied and the device is driven. Figure 46 shows the brightness-current density characteristics, Figure 47 shows the brightness-voltage characteristics, Figure 48 shows the current efficiency-brightness characteristics, Figure 49 shows the current density-voltage characteristics, Figure 50 shows the external quantum efficiency-brightness characteristics, Figure 51 shows the blue index-brightness characteristics, and Figure 52 shows the field emission spectra of light-emitting device B-3 and comparative light-emitting devices B-4 to B-6. In the legend of Figures 38 to 52, light-emitting device B-1, comparative light-emitting device B-2, light-emitting device B-3, comparative light-emitting device B-4, comparative light-emitting device B-5, and comparative light-emitting device B-6 are referred to as Device B-1, Comp. device B-2, Device B-3, Comp. device B-4, Comp. device B-5, and Comp. device B-6, respectively.

[0497] The Blue Index (BI) is a value obtained by dividing the current efficiency (cd / A) by the y value of the CIE(x,y) chromaticity, and is one of the indicators that represent the emission characteristics of blue light. Blue light tends to have higher color purity as the chromaticity y value decreases. By using blue light with a small chromaticity y value and high color purity, it becomes possible to express a wide range of blue colors in a display, and the brightness of blue required to express white in the display decreases, resulting in the effect of reducing the power consumption of the display. For this reason, BI, which is a current efficiency that takes into account the chromaticity y value, one of the indicators of blue purity, is sometimes suitably used as a means of representing the efficiency of blue light emission, and it can be said that light-emitting devices with a high BI are more efficient as blue light-emitting devices used in displays.

[0498] Furthermore, the brightness of each light-emitting device is 100 cd / m². 2 Table 11 shows the main characteristics of the vicinity. A spectroradiometer (Topcon SR-UL1R) was used to measure luminance, CIE chromaticity, and emission spectrum. The external quantum efficiency was calculated using the luminance and emission spectrum measured with the spectroradiometer, assuming that the light distribution characteristics were Lambertsian.

[0499] [Table 11]

[0500] Figures 38 to 52 and Table 11 clearly show that the light-emitting device B-1 is a light-emitting device with good characteristics, exhibiting blue light emission originating from 3,10PCA2Nbf(IV)-02.

[0501] Furthermore, Figures 39 and 41 show that light-emitting device B-1 has a lower drive voltage than comparative light-emitting device B-2 at low brightness or low current density. Additionally, Figures 40, 42, and 43 show that light-emitting device B-1 has higher current efficiency, external quantum efficiency, and blue index than comparative light-emitting device B-2.

[0502] Furthermore, Figures 48, 50, and 51 show that light-emitting device B-3 has higher current efficiency, external quantum efficiency, and blue index over a wider brightness range than comparative light-emitting devices B-4 to B-6.

[0503] Here, the ordinary refractive index (n) of the vapor-deposited films of the main organic compounds used in each light-emitting device. o Table 12 shows the GSP_slope for each organic compound film. In Table 12, the ordinary refractive index is shown at a wavelength of 633 nm. A spectroscopic ellipsometer (M-2000U, manufactured by J.A. Woolam Japan Co., Ltd.) was used to measure the ordinary refractive index, and the sample used for measurement was a film in which each layer material was deposited on a quartz substrate by vacuum deposition to a film thickness of 50 nm. In addition, in Table 12, the GSP_slope of each organic compound film was measured by the method shown in Embodiment 1.

[0504] [Table 12]

[0505] As shown in Table 12, mmTMSPh-mDMePyPTzn, an organic compound according to one embodiment of the present invention, is an organic compound in which the refractive index of the film is lower than that of 6mBP-4Cz2PPm and 2mPCCzPDBq, and the GSP_slope of the film is smaller than that of mmtBuPh-mDMePyPTzn.

[0506] From the above results, it was found that the light-emitting device using the organic compound according to one embodiment of the present invention is a light-emitting device with a low driving voltage and high luminous efficiency. This is because the organic compound according to one embodiment of the present invention is an organic compound with a low refractive index and a small GSP_slope of the film. By using the organic compound according to one embodiment of the present invention in the electron transport layer, the light extraction efficiency from the light-emitting layer in the light-emitting device is improved, and it becomes possible to apply voltage to the light-emitting layer effectively. [Examples]

[0507] ≪Synthesis Example 2≫ This synthesis example demonstrates the synthesis method and properties of 2-{[3',5'-bis(trimethylsilyl)]-5-(pyrimidine-5-yl)biphenyl-3-yl}-4,6-diphenyl-1,3,5-triazine (abbreviation: mmTMSPh-mPmPTzn) (structural formula (102)), an organic compound according to one embodiment of the present invention.

[0508] [ka]

[0509] <Step 1: Synthesis of 2-{5-chloro-[3',5'-bis(trimethylsilyl)]biphenyl-3-yl}-4,6-diphenyl-1,3,5-triazine> 7.5 g (18 mmol) of 2-(3-bromo-5-chlorophenyl)-4,6-diphenyl-1,3,5-triazine, 6.8 g (20 mmol) of 2-[3,5-bis(trimethylsilyl)phenyl]-4,4,5,5-tetramethyl-1,3,2-dioxaborolane, 4.9 g (36 mmol) of potassium carbonate, 70 mL of toluene, 35 mL of ethanol (EtOH), and 18 mL of water were added to a three-necked flask and the mixture was degassed. After degassing, 40 mg (0.18 mmol) of palladium(II) acetate (Pd(OAc)2) and 0.22 g (0.71 mmol) of tris(2-methylphenyl)phosphine (P(o-tolyl)3) were added, and the mixture was stirred at 80°C for 11 hours. After the reaction was complete, toluene and water were added to the mixture, and the mixture was separated into an organic layer and an aqueous layer. The aqueous layer was extracted with toluene, and the extract solution and the organic layer were combined and magnesium sulfate was added to adsorb the water. The mixture was filtered naturally, and the resulting filtrate was concentrated to obtain a pale orange solid. This solid was purified by silica gel column chromatography using toluene:hexane = 1:10 as the developing solvent. 10.4 g of a white solid containing the target product was obtained. The synthesis scheme for Step 1 is shown below (a-3).

[0510] [ka]

[0511] <Step 2: Synthesis of mmTMSPh-mPmPTzn> 5.0 g (8.8 mmol) of 2-{5-chloro-[3',5'-bis(trimethylsilyl)]biphenyl-3-yl}-4,6-diphenyl-1,3,5-triazine obtained in Step 1, 2.2 g (18 mmol) of 5-pyrimidylboronic acid, 3.7 g (27 mmol) of potassium carbonate, 50 mL of tetrahydrofuran (THF), and 13 mL of water were added to a three-necked flask and degassed. After degassing, 40 mg (0.18 mmol) of palladium(II) acetate (Pd(OAc)2) and 0.17 g (0.35 mmol) of 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl (XPhos) were added and the mixture was stirred at 65°C for 18 hours. After the reaction was complete, toluene and water were added to the mixture and the mixture was separated into an organic layer and an aqueous layer. The aqueous layer was extracted with toluene, and the extract solution and the organic layer were combined and magnesium sulfate was added to adsorb the water. The mixture was filtered naturally, and the resulting filtrate was concentrated to obtain a yellow solid. This solid was purified by silica gel column chromatography with the developing solvent varied from toluene:ethyl acetate = 10:1 to 5:1 to obtain a pale yellow solid. This solid was recrystallized with toluene / ethanol to obtain 2.6 g of the target white solid (yield: 49%). The obtained 2.6 g of solid was purified by sublimation using the train sublimation method. The sublimation purification conditions were heating the solid at a pressure of 3.3 Pa and 260 °C for 2 hours. After sublimation purification, 1.1 g of the target white solid (yield: 44%) was obtained. The synthesis scheme for Step 2 is shown below (a-4).

[0512] [ka]

[0513] Nuclear magnetic resonance spectroscopy of the white solid obtained in step 2 above ( 1 The results of the analysis by 1H-NMR are shown below. 1Figure 53 shows the 1H-NMR chart, and Figure 54 shows a magnified view of the range from 7 ppm to 9.5 ppm in Figure 53. From these results, it was found that in this synthesis example, the organic compound mmTMSPh-mPmPTzn, which is one embodiment of the present invention, was obtained.

[0514] 1 H-NMR.δ(CDCl3,500MHz):0.38(s,18H), 7.58-7.66(m,6H), 7.79(t,1H,J=1.1Hz), 7.88(d,2H,J=1.1Hz), 7.9 9(t,1H,J=1.7Hz), 8.79-8.82(m,4H), 8.97(t,1H,J=1.6Hz), 9.12(t,1H,J=1.6Hz), 9.19(s,2H), 9.32(s,1H).

[0515] <Emission and absorption spectrum measurement> Next, Figure 55 shows the results of measuring the absorption and emission spectra of a dichloromethane solution of mmTMSPh-mPmPTzn, similar to the emission and absorption spectrum measurements in Example 1. Figure 56 also shows the absorption and emission spectra of the thin film.

[0516] Figure 55 shows that the dichloromethane solution of mmTMSPh-mPmPTzn exhibited a peak at 270 nm in its absorption spectrum and a peak at 390 nm (excitation wavelength 270 nm) in its emission spectrum. Figure 56 shows that the thin film of mmTMSPh-mPmPTzn exhibited a peak at 266 nm in its absorption spectrum and a peak at 396 nm (excitation wavelength 300 nm) in its emission spectrum. Figures 55 and 56 indicate that mmTMSPh-mPmPTzn does not exhibit absorption in the visible region (wavelengths longer than 450 nm).

[0517] <Measuring refractive index> Fig. 57 shows the results of measuring the refractive index of the mmTMSPh-mPmPTzn film in the same manner as the measurement of the refractive index in Example 1. From Fig. 57, it was found that the mmTMSPh-mPmPTzn film has an ordinary light refractive index in the range of 1.50 or more and 1.75 or less throughout the blue light emission region (wavelength of 455 nm or more and 465 nm or less), and also has an ordinary light refractive index at a wavelength of 633 nm in the range of 1.45 or more and 1.70 or less, indicating that it is a film with a low refractive index.

[0518] <Measurement of GSP_slope and Pz> Next, the GSP_slope of the mmTMSPh-mPmPTzn vapor-deposited film was measured. The measurement was performed by the method shown in Embodiment 1. Also, the magnitude (Pz) in the direction perpendicular to the substrate surface of the SOP of the mmTMSPh-mPmPTzn vapor-deposited film was calculated. Note that Pz is a value obtained by multiplying the GSP_slope by the dielectric constant of the film. The dielectric constant of the film can be a value obtained by multiplying the square of the ordinary light refractive index n o (value at a wavelength of 633 nm) by the vacuum permittivity. The measurement results are shown in Table 13. For comparison, Table 13 also shows the GSP_slope and Pz of the vapor-deposited film of 2-{3-[(3,5-di-tert-butyl)phenyl]-5-(pyrimidin-5-yl)phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: mmtBuPh-mPmPTzn). The chemical formulas of mmTMSPh-mPmPTzn, which is an organic compound of one aspect of the present invention, and mmtBuPh-mPmPTzn, which is a comparative organic compound, are shown below.

[0519]

Chemical formula

[0520]

Table 13

[0521] As shown in Table 13, mmTMSPh-mPmPTzn, an organic compound according to one embodiment of the present invention, had smaller GSP_slope and Pz values ​​in its film than mmtBuPh-mPmPTzn, a comparative organic compound. mmTMSPh-mPmPTzn has a trisubstituted silyl group in which the quaternary carbon atoms of the two tert-butyl groups of mmtBuPh-mPmPTzn are each replaced with silicon atoms. Since silicon atoms have lower electronegativity compared to carbon atoms, it can be considered that mmTMSPh-mPmPTzn has a smaller permanent electric dipole moment than mmtBuPh-mPmPTzn, resulting in smaller Pz and GSP_slope values ​​in the deposited film. [Examples]

[0522] In this example, we fabricated light-emitting devices G-6 using the organic compound mmTMSPh-mPmPTzn, one embodiment of the present invention whose synthesis method was described in Example 4, and comparative light-emitting devices G-7 and G-8 using comparative organic compounds. The results of measurements of the characteristics of each device are described below. These light-emitting devices exhibit green phosphorescence. The structural formulas of the organic compounds used in each light-emitting device are shown below.

[0523] [ka]

[0524] <Method for fabricating the light-emitting device G-6> Light-emitting device G-6 differs from light-emitting device G-1 in that it forms a first electron transport layer 914_1 by depositing mmTMSPh-mPmPTzn, an organic compound according to one aspect of the present invention, to a thickness of 20 nm, and a second electron transport layer 914_2 by depositing mPPhen2P to a thickness of 20 nm. The other components were fabricated in the same manner as light-emitting device G-1.

[0525] <Method for fabricating the comparative light-emitting device G-7> Comparative light-emitting device G-7 differs from light-emitting device G-6 in that it replaces mmTMSPh-mPmPTzn, an organic compound according to one aspect of the present invention used in the first electron transport layer 914_1 of light-emitting device G-6, with mmtBuPh-mPmPTzn, a comparative organic compound. The other components were fabricated in the same manner as light-emitting device G-6.

[0526] <Method for fabricating the comparative light-emitting device G-8> Comparative light-emitting device G-8 differs from light-emitting device G-6 in that it replaces mmTMSPh-mPmPTzn, an organic compound according to one aspect of the present invention used in the first electron transport layer 914_1 of light-emitting device G-6, with 2mPCCzPDBq, a comparative organic compound. The other components were fabricated in the same manner as light-emitting device G-6.

[0527] Table 14 summarizes the device structures of light-emitting device G-6, comparative light-emitting device G-7, and comparative light-emitting device G-8.

[0528] [Table 14]

[0529] <Light-emitting device characteristics> The above-mentioned light-emitting device was sealed with a glass substrate in a glove box under a nitrogen atmosphere to prevent exposure to the atmosphere (sealing material was applied around the element, UV treatment was performed during sealing, and heat treatment was performed at 80°C for 1 hour). After this, the characteristics of the light-emitting device were measured.

[0530] Figure 58 shows the luminance-current density characteristics of light-emitting device G-6, comparative light-emitting device G-7, and comparative light-emitting device G-8, Figure 59 shows the luminance-voltage characteristics, Figure 60 shows the current efficiency-luminance characteristics, Figure 61 shows the current density-voltage characteristics, Figure 62 shows the external quantum efficiency-luminance characteristics, and Figure 63 shows the field emission spectra. In addition, light-emitting device G-6, comparative light-emitting device G-7, and comparative light-emitting device G-8 are subjected to 2mA (50mA / cm²). 2Figure 64 shows the change in brightness with respect to the operating time when a constant current is applied and the device is driven. In the legend of Figures 58 to 64, the light-emitting device G-6, the comparative light-emitting device G-7, and the comparative light-emitting device G-8 are referred to as Device G-6, Comp. device G-7, and Comp. device G-8, respectively.

[0531] Furthermore, the brightness of each light-emitting device is 1000 cd / m². 2 Table 15 shows the main characteristics of the vicinity. A spectroradiometer (Topcon SR-UL1R) was used to measure luminance, CIE chromaticity, and emission spectrum. The external quantum efficiency was calculated using the luminance and emission spectrum measured with the spectroradiometer, assuming that the light distribution characteristics were Lambertsian.

[0532] [Table 15]

[0533] Figures 58 to 64 and Table 15 clearly show that the light-emitting device G-6 is a light-emitting device with good characteristics, exhibiting green light emission originating from Ir(5mppy-d3)2(mbfpypy-d3).

[0534] Furthermore, Figures 59 and 61 show that the light-emitting device G-6 has a lower drive voltage than the comparative light-emitting device G-7. Also, Figures 60 and 62 show that the light-emitting device G-6 has a higher luminous efficiency than the comparative light-emitting device G-8. Finally, Figure 64 shows that the brightness change with respect to operating time for the light-emitting device G-6 is smaller than that of the comparative light-emitting device G-7 and comparable to that of the comparative light-emitting device G-8, indicating that it is a long-life light-emitting device.

[0535] Here, the ordinary refractive index (n) of the film co-deposited with the same combination of organic compounds and mixing ratio as the first electron transport layer 914_1 and the light-emitting layer 913 of each light-emitting device is determined. oTable 16 shows the values ​​of Pz and GSP_slope for each organic compound film. In Table 16, the ordinary refractive index is shown at a wavelength of 532 nm. A spectroscopic ellipsometer (M-2000U, manufactured by J.A. Woolam Japan Co., Ltd.) was used to measure the ordinary refractive index, and the sample used for measurement was a film in which each layer material was deposited on a quartz substrate by vacuum deposition to a thickness of 50 nm. In addition, in Table 16, the Pz and GSP_slope of each organic compound film were measured by the method shown in Embodiment 1.

[0536] [Table 16]

[0537] As shown in Table 16, mmTMSPh-mPmPTzn, an organic compound according to one embodiment of the present invention, has a lower refractive index than the comparative organic compounds mmtBuPh-mPmPTzn and 2mPCCzPDBq, and has smaller Pz and GSP_slope than mmtBuPh-mPmPTzn. Furthermore, as shown in Table 16, mmTMSPh-mPmPTzn, an organic compound according to one embodiment of the present invention, has a smaller Pz than a film co-deposited with the same combination of organic compounds and mixing ratio as the light-emitting layer 913. On the other hand, mmtBuPh-mPmPTzn, a comparative organic compound, has a larger Pz than a film co-deposited with the same combination of organic compounds and mixing ratio as the light-emitting layer 913.

[0538] As described above, the light-emitting device G-6 has a higher luminous efficiency than the comparative light-emitting device G-8. This result can be explained by the fact that the mmTMSPh-mPmPTzn used in the first electron transport layer 914_1 of the light-emitting device G-6 has a lower refractive index than the 2mPCCzPDBq used in the first electron transport layer 914_1 of the comparative light-emitting device G-8, as shown in Table 16. In other words, in the light-emitting device G-6, using mmTMSPh-mPmPTzn, which has a lower refractive index, in the first electron transport layer 914_1 improved the light extraction efficiency and increased the luminous efficiency.

[0539] Furthermore, as mentioned above, the light-emitting device G-6 has a lower driving voltage and a longer lifespan than the comparative light-emitting device G-7. This result can be explained by the fact that, as shown in Table 16, the mmTMSPh-mPmPTzn used in the first electron transport layer 914_1 of the light-emitting device G-6 has a smaller Pz than the film co-deposited with the same combination of organic compounds and mixing ratio as the light-emitting layer 913, while the mmtBuPh-mPmPTzn used in the comparative light-emitting device G-7 has a larger Pz than the film co-deposited with the same combination of organic compounds and mixing ratio as the light-emitting layer 913. In other words, in the light-emitting device G-6, by using mmTMSPh-mPmPTzn, a film with a Pz value smaller than that of the light-emitting layer 913, as the first electron transport layer 914_1, a positive virtual interfacial charge is generated at the interface between the light-emitting layer 913 and the first electron transport layer 914_1, thereby improving the electron injection from the first electron transport layer 914_1 to the light-emitting layer 913. Furthermore, the carrier balance of the light-emitting device is improved, resulting in a longer lifespan. [Explanation of symbols]

[0540] 101 First electrode 102 Second electrode 103 EL layer 103a EL layer 103b EL layer 103B EL layer 103G EL layer 103R EL layer 106 Charge generation layer 106a Charge generation layer 106b Charge generation layer 110B subpixel 110G sub-pixels 110R sub-pixel 110 subpixels 111 Hole injection layer 111a Hole injection layer 111b Hole injection layer 112 Hole transport layer 112a Hole transport layer 112b Hole transport layer 112B Conductive layer 112R conductive layer 113 Emitting layer 113a Light-emitting layer 113b Emitting layer 113c emissive layer 114 Electron transport layer 114a Electron transport layer 114b Electron transport layer 115 Electron injection layer 115a Electron injection layer 115b Electron injection layer 120 circuit boards 122 Resin layer 125 Inorganic insulating layer 126B Conductive layer 126R conductive layer 127 Insulating layer 128 layers 129R conductive layer 129B Conductive layer 130B Light-emitting device 130G Light-emitting Device 130R Light-emitting Device 130 Light-emitting devices 135 Protective layer 136B Colored layer 136G colored layer 136R colored layer 140 Connection part 151B Conductive layer 151C conductive layer 151G conductive layer 151R conductive layer 151 Conductive layer 152B Conductive layer 152C conductive layer 152G conductive layer 152R conductive layer 152 Conductive layer 153 Insulating layer 155 Common layer 156B Insulating layer 156C insulating layer 156G insulating layer 156R Insulating Layer 156 Insulating layer 158R Sacrifice Layer 158G Sacrifice Layer 158B Sacrifice Layer 166 Conductive layer 174 Insulating layer 175 Insulating layer 177 pixel section 201 Transistors 204 Connection part 205 transistors 211 Insulating layer 213 Insulating layer 214 Insulating layer 215 Insulating layer 221 Conductive layer 222a conductive layer 222b Conductive layer 223 Conductive layer 224R conductive layer 224B Conductive layer 224G conductive layer 224C conductive layer 240 capacity 241 Conductive layer 243 Insulating layer 245 Conductive layer 254 Insulating layer 255 Insulating layer 256 plug 261 Insulating layer 271 Plug 280 Display Modules 281 Display section 282 Circuit section 283a Pixel Circuit 283 Pixel Circuit Section 284a pixels 284 pixel section 285 Terminal section 286 Wiring section 290 FPC 291 circuit boards 292 circuit boards 301 circuit board 310 transistors 311 Conductive layer 312 Low resistance region 313 Insulating layer 314 Insulating layer 315 element isolation layer 351 circuit board 352 circuit boards 353 FPC 354 IC 355 Wiring 600A display device 600B display device 600C display unit 700A electronic equipment 700B Electronic equipment 721 cabinet 723 Mounting part 727 Earphone section 750 Earphones 751 Display Panel 753 Optical components 756 Display area 757 frames 758 Nose pads 900 glass substrate 901 First electrode 902 Second electrode 911 Hole injection layer 912 Hole transport layer 913 Emitting layer 914_1 First electron transport layer 914_2 Second electron transport layer 915 Electron injection layer 950 Glass Substrate 951 Anode 952 layers 953 layers 954 layers 955 layers 956 layers 957 Cathode 6500 Electronic equipment 6501 enclosure 6502 Display section 6503 Power button 6504 button 6505 Speaker 6506 Mike 6507 Camera 6508 Light source 6510 Protective component 6511 Display Panel 6512 Optical components 6513 Touch Sensor Panel 6515 FPC 6516 IC 6517 Printed circuit board 6518 Battery 7000 Display 7100 Television equipment 7151 Remote control unit 7171 enclosure 7173 Stand 7200 Notebook Personal Computer 7211 enclosure 7212 Keyboard 7213 Pointing device 7214 External connection port 7300 Digital Signage 7301 enclosure 7303 Speaker 7311 Information terminal 7400 Digital Signage 7401 pillars 7411 Information terminal 9000 cabinets 9001 Display section 9002 Camera 9003 Speaker

Claims

1. An organic compound represented by the general formula (G1). 【Chemistry 1】 (In general formula (G1), Q １ to Q ３ each independently represents N or CH (including CD), and at least two of Q １ to Q ３ are N, R １ to R ３ each independently represents an alkyl group having 1 to 6 carbon atoms or a phenyl group, n represents an integer of 2 or more and 5 or less, and R １０ represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms, and R １１ to R ２４ each independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a substituted or unsubstituted aryl group having 6 or more and 30 or less carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 or more and 30 or less carbon atoms, and at least one of R １１ to R ２４ is a substituted or unsubstituted heteroaryl group having 3 or more and 30 or less carbon atoms. A plurality of R １ may be the same or different. A plurality of R ２ may be the same or different. A plurality of R ３ may be the same or different. When 5 - n is 2 or more, a plurality of R １０ may be the same or different.)

2. An organic compound represented by the general formula (G2). 【Chemistry 2】 (In the general formula (G2), Q １ ~Q ３ Each independently represents N or CH (including CD), and Q １ ~Q ３ At least two of them are N, and R １ ~R ３ Each independently represents an alkyl group or phenyl group having 1 to 6 carbon atoms, n represents an integer between 2 and 5, and R １０ R represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms. １２ ~R ２４ Each of the following independently represents hydrogen (including deuterium), a C1 to C6 alkyl group, a C3 to C10 cycloalkyl group, or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, and Hy represents a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms. １ They may be the same or different. Multiple R ２ They may be the same or different. Multiple R ３ They may be the same or different. If 5-n is 2 or more, there may be multiple R １０ They may be the same or different.

3. In claim 1 or claim 2, The substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms is an organic compound containing nitrogen.

4. In claim 1 or claim 2, An organic compound wherein one or more atoms constituting the aromatic ring of the substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms are nitrogen atoms.

5. In claim 1 or claim 2, The substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms is an organic compound in which the heteroaryl group is a substituted or unsubstituted pyridinyl group, a substituted or unsubstituted pyrimidinyl group, or a substituted or unsubstituted pyrazinyl group.

6. In claim 5, The substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms is an organic compound having at least one of an alkyl group having 1 to 6 carbon atoms and a cycloalkyl group having 3 to 10 carbon atoms.

7. An organic compound represented by the general formula (G3). 【Transformation 3】 (In the general formula (G3), Q １ ~Q ３ Each independently represents N or CH (including CD), and Q １ ~Q ３ At least two of them are N, and R １ ~R ３ Each independently represents an alkyl group or phenyl group having 1 to 6 carbon atoms, n represents an integer between 2 and 5, and R １０ R represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms. １２ ~R ２４ Each independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, R ２５ ~R ２８ Each of these independently represents hydrogen (including deuterium), a C1-C6 alkyl group, or a C3-C10 cycloalkyl group. １ They may be the same or different. Multiple R ２ They may be the same or different. Multiple R ３ They may be the same or different. If 5-n is 2 or more, there may be multiple R １０ They may be the same or different.

8. An organic compound represented by the general formula (G4). 【Chemistry 4】 (In the general formula (G4), Q １ ~Q ３ Each independently represents N or CH (including CD), and Q １ ~Q ３ At least two of them are N, and R １ ~R ３ Each independently represents an alkyl group or phenyl group having 1 to 6 carbon atoms, n represents an integer between 2 and 5, and R １０ R represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms. １２ ~R ２４ Each independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, R ２５ ~R ２８ Each of these independently represents hydrogen (including deuterium), a C1-C6 alkyl group, or a C3-C10 cycloalkyl group. １ They may be the same or different. Multiple R ２ They may be the same or different. Multiple R ３ They may be the same or different. If 5-n is 2 or more, there may be multiple R １０ They may be the same or different.

9. In any one of claims 1, 2, 7, and 8, An organic compound in which n is 2 or 3.

10. In any one of claims 1, 2, 7, and 8, An organic compound in which n is 2.

11. An organic compound represented by the general formula (G5). 【Transformation 5】 (In the general formula (G5), Q １ ~Q ３ Each independently represents N or CH (including CD), and Q １ ~Q ３ At least two of them are N, and R １ ~R ６ Each independently represents an alkyl group or phenyl group having 1 to 6 carbon atoms, R ８ ~R １０ Each independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, or a cycloalkyl group having 3 to 10 carbon atoms, R １２ ~R ２４ Each independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, or a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, R ２５ ~R ２８ Each of these independently represents hydrogen (including deuterium), a C1-C6 alkyl group, or a C3-C10 cycloalkyl group.

12. In any one of claims 7, 8, and 11, R ２５ ~R ２８ An organic compound in which at least one of the elements is an alkyl group having 1 to 6 carbon atoms or a cycloalkyl group having 3 to 10 carbon atoms.

13. In any one of claims 1, 2, 7, 8 and 11, Q １ ~Q ３ However, these are all organic compounds where the element is N.

14. An organic compound represented by structural formula (100). 【Transformation 6】

15. A light-emitting device having an organic compound according to any one of claims 1, 2, 7, 8, and 11.

16. It comprises a first electrode, a second electrode, and an EL layer located between the first electrode and the second electrode, The EL layer comprises an emissive layer and an electron transport layer. The electron transport layer is located between the light-emitting layer and the second electrode. The distance between the electron transport layer and the second electrode is 5 nm or less. The electron transport layer comprises an organic compound according to any one of claims 1, 2, 7, 8, and 11, in a light-emitting device.

17. It comprises a first electrode, a second electrode, and an EL layer located between the first electrode and the second electrode, The EL layer comprises an emissive layer and an electron transport layer. The electron transport layer is located between the light-emitting layer and the second electrode. The electron transport layer is a mixed layer having a first organic compound and a metal complex. The first organic compound is a light-emitting device having a π-electron-deficient heteroaromatic ring and a trialkylsilyl group having 3 to 18 carbon atoms.

18. A light-emitting device according to claim 17, wherein the π-electron-deficient heteroaromatic ring is a pyrimidine ring or a triazine ring.

19. It comprises a first electrode, a second electrode, and an EL layer located between the first electrode and the second electrode, The EL layer comprises an emissive layer and an electron transport layer. The electron transport layer is located between the light-emitting layer and the second electrode. The electron transport layer is a mixed layer having a first organic compound and a metal complex. The first organic compound is an organic compound represented by general formula (G0), and the device is a light-emitting device. 【Transformation 7】 (In the general formula (G0), Q １ ~Q ３ Each independently represents N or CH, and Q １ ~Q ３ At least two of them are N, and R １ ~R ３ Each independently represents an alkyl group or phenyl group having 1 to 6 carbon atoms, n represents an integer between 1 and 5, and R １０ ~R ２４ Each of these independently represents hydrogen (including deuterium), an alkyl group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 10 carbon atoms, a trisubstituted silyl group having 3 to 18 carbon atoms, a substituted or unsubstituted aryl group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms. When n is 2 or more, multiple R １ They may be the same or different. Multiple R ２ They may be the same or different. Multiple R ３ They may be the same or different. If 5-n is 2 or more, there may be multiple R １０ They may be the same or different.

20. In any one of claims 17 to 19, A light-emitting device in which the distance between the electron transport layer and the second electrode is 5 nm or less.

21. In any one of claims 17 to 19, The aforementioned metal complex contains an alkali metal, and is a light-emitting device.

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