Light-emitting devices

Abstract

To provide a novel light-emitting device, or to provide a light-emitting device with good luminous efficiency. To provide a light-emitting device with a good lifespan. Or, to provide a light-emitting device with a low drive voltage. We will provide the service. [Solution] The anode has a cathode and an EL layer located between the anode and the cathode, The EL layer has an emissive layer and an electron transport layer, and the electron transport layer is connected to the emissive layer and the cathode. Located between, the electron transport layer has an electron transport material, and the electron transport material has a first skeleton The first organic compound has a second skeleton and a third skeleton, wherein the first skeleton has electrons The second skeleton has a function of transporting, the third skeleton has a function of receiving holes, and the third skeleton has The present invention provides a light-emitting device having a monocyclic and π-electron-deficient heteroaromatic ring.

Description

[Technical Field]

[0001] One aspect of the present invention is a light-emitting device, a light-emitting element, a display module, and a lighting module. The present invention relates to display devices, light-emitting devices, electronic devices, and lighting devices. One aspect of the present invention is as described above. The technical field of one aspect of the invention disclosed herein is not limited to the technical field of products, methods. , or relating to a manufacturing method. Or, one aspect of the present invention relates to a process, machine This relates to the manufacture or composition of matter. There is. Therefore, more specifically, one aspect of the technical field of the present invention disclosed herein is: Semiconductor devices, display devices, liquid crystal display devices, light-emitting devices, lighting devices, energy storage devices, memory devices, imaging devices Examples include devices, methods for driving them, or methods for manufacturing them. . [Background technology]

[0002] Electroluminescence (EL) using organic compounds The practical application of light-emitting devices (organic EL elements) that utilize ence is progressing. The basic configuration of the device involves sandwiching an organic compound layer (EL layer) containing a light-emitting material between a pair of electrodes. That is the case. A voltage is applied to this element to inject carriers and recombine those carriers. By utilizing energy, it is possible to obtain light emission from light-emitting materials.

[0003] Since such light-emitting devices are self-emissive, when used as pixels in a display, they become liquid crystals. Compared to other types, it has advantages such as higher visibility and the elimination of the need for a backlight, and flat panel displays It is suitable as a spray element. Furthermore, a display using such a light-emitting device is 、The ability to be manufactured in a thin and lightweight form is also a significant advantage. Furthermore, it is also one of the characteristics that it has a very high response speed. This is one of the characteristics.

[0004] In addition, since these light-emitting devices can form the light-emitting layer continuously in two dimensions, it is possible to obtain planar light emission. This is a characteristic that is difficult to achieve with point light sources typified by incandescent bulbs and LEDs, or linear light sources typified by fluorescent lamps. Therefore, it has high utility value as a planar light source applicable to lighting and the like.

[0005] Displays and lighting devices using such light-emitting devices are suitable for various electronic devices, but research and development are being advanced to obtain light-emitting devices with better efficiency and lifespan.

[0006] In Patent Document 1, a configuration is disclosed in which a hole-transporting material having a HOMO level between the HOMO level of the hole-injecting layer and the HOMO level of the host material is provided between the hole-transporting layer in contact with the hole-injecting layer and the light-emitting layer.

[0007] The characteristics of light-emitting devices have improved remarkably, but it still has to be said that they are insufficient to meet the high demands for all characteristics, including efficiency and durability.

Prior Art Documents

Patent Documents

[0008]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0009] ​​​​​Therefore, one aspect of the present invention aims to provide a novel light-emitting device. Or, The objective is to provide a light-emitting device with good luminescence efficiency, or a light-emitting device with a good lifespan. The objective is to provide a device, or to provide a light-emitting device with a low drive voltage. The objective is to provide a novel compound. Alternatively, one aspect of the present invention aims to provide a novel compound.

[0010] Alternatively, in another aspect of the present invention, a highly reliable light-emitting device, electronic device, and display device are provided, respectively. The purpose is to provide. Alternatively, in another aspect of the present invention, a light-emitting device with low power consumption. The purpose is to provide a device, electronic equipment, and display device, respectively.

[0011] The present invention only needs to solve one of the above-mentioned problems. [Means for solving the problem]

[0012] One aspect of the present invention comprises an anode, a cathode, and an EL layer located between the anode and the cathode. The EL layer has an emissive layer and an electron transport layer, and the electron transport layer has an emissive layer and an electron transport layer. Located between the poles, the electron transport layer has an electron transport material, and the electron transport material is a first An organic compound having a first skeleton, a second skeleton, and a third skeleton, wherein the first skeleton is The second skeleton has the function of transporting electrons, and the third has the function of receiving holes. The underlying structure is a light-emitting device having a monocyclic, π-electron-deficient heteroaromatic ring.

[0013] Alternatively, another aspect of the present invention comprises an anode, a cathode, and a position located between the anode and the cathode. It has an EL layer, the EL layer has an emissive layer and an electron transport layer, and the electron transport layer is an electron The electron transport material comprises a first skeleton, a second skeleton, and a third skeleton. The organic compound wherein the first skeleton has the function of transporting electrons, and the second skeleton It has the function of accepting holes, and the second skeleton has two or more condensed aromatic hydrocarbon rings The third skeleton has a monocyclic and π-electron-deficient heteroaromatic ring, which is a light-emitting element. It's a vice.

[0014] Alternatively, in another aspect of the present invention, in the above configuration, the second skeleton is formed by condensation of three or more rings This is a light-emitting device having an aromatic hydrocarbon ring.

[0015] Alternatively, in another aspect of the present invention, in the above configuration, the second skeleton is three-ring or four-ring It is a light-emitting device that is a condensed aromatic hydrocarbon ring.

[0016] Alternatively, in another aspect of the present invention, in the above configuration, carbon forming the ring of the skeleton of the aforementioned 2 This is a light-emitting device where the number of elements is 14 or more.

[0017] Alternatively, in another aspect of the present invention, in the above configuration, the condensed aromatic hydrocarbon ring is a 6-membered ring It is a light-emitting device composed solely of [this element].

[0018] Alternatively, in another aspect of the present invention, in the above configuration, the second skeleton is an anthracene ring phenanthrene ring, benzofluorene ring, tetracene ring, chrysene ring, triphenylene This is a light-emitting device that includes either a ring or a pyrene ring.

[0019] Alternatively, in another aspect of the present invention, in the above configuration, the second skeleton is an anthracene ring It is a light-emitting device.

[0020] Alternatively, in another aspect of the present invention, in the above configuration, the electron transport layer is a metal, a metal salt, This is a light-emitting device further comprising a metal oxide or an organometallic salt.

[0021] Alternatively, another aspect of the present invention comprises an anode, a cathode, and a position located between the anode and the cathode. The EL layer has an EL layer, the EL layer has a hole injection layer, an emissive layer, and an electron transport layer, the hole The injection layer is located between the anode and the light-emitting layer, and the electron transport layer is located between the light-emitting layer and Located between the cathode, the hole injection layer comprises a hole transport material and an acceptor material. The electron transport layer comprises an electron transport material and a metal, metal salt, metal oxide, or organometallic salt. The hole transport material has hole transport properties and its HOMO level is -5.7 The acceptor material is an organic compound with an eV of 1 to 5.4 eV, and the hole transport material is the same as the hole transport material. The material is an electron-accepting substance, and the electron transport material comprises a first skeleton and a second skeleton, An organic compound having a third skeleton, wherein the first skeleton has the function of transporting electrons. The second skeleton has the function of receiving holes, and the third skeleton is a single ring and π-electric This is a light-emitting device having a heteroaromatic ring that is deficient in certain components.

[0022] Alternatively, in another aspect of the present invention, in the above configuration, the second skeleton has two to four rings. It is a light-emitting device that is a condensed aromatic hydrocarbon ring.

[0023] Alternatively, in another aspect of the present invention, in the above configuration, the second skeleton is three-ring or four-ring It is a light-emitting device that is a condensed aromatic hydrocarbon ring.

[0024] Alternatively, in another aspect of the present invention, in the above configuration, the second skeleton is a naphthalene ring, Fluorene ring, anthracene ring, phenanthrene ring, tetracene ring, chrysene ring, truffle This is a light-emitting device containing either an enylene ring or a pyrene ring.

[0025] Alternatively, in another aspect of the present invention, in the above configuration, carbon forming the ring of the skeleton of the aforementioned 2 This is a light-emitting device where the number of elements is 14 or more.

[0026] Alternatively, in another aspect of the present invention, in the above configuration, the condensed aromatic hydrocarbon ring is a 6-membered ring It is a light-emitting device composed solely of [this element].

[0027] Alternatively, in another aspect of the present invention, in the above configuration, the second skeleton is an anthracene ring It is a light-emitting device.

[0028] Alternatively, in another aspect of the present invention, in the above configuration, the acceptor material is an organic compound It is a light-emitting device.

[0029] Alternatively, in another aspect of the present invention, in the above configuration, the metal, metal salt, metal oxide, Alternatively, the organometallic salt is a metal complex containing an alkali metal or alkaline earth metal. It's a vice.

[0030] Alternatively, in another aspect of the present invention, in the above configuration, the metal, metal salt, metal oxide, Alternatively, an organometallic salt may contain a ligand with nitrogen and oxygen, and an alkali metal or alkaline earth metal. It is a light-emitting device that is a metal complex having [a specific characteristic].

[0031] Alternatively, in another aspect of the present invention, in the above configuration, the metal, metal salt, metal oxide, Alternatively, organometallic salts combine a ligand containing an 8-hydroxyquinolinate structure with a monovalent metal ion. It is a light-emitting device that is a metal complex.

[0032] Alternatively, in another aspect of the present invention, in the above configuration, the metal, metal salt, metal oxide, Alternatively, an organometallic salt may be a lithium complex having a ligand containing an 8-hydroxyquinolinate structure. It is a light-emitting device.

[0033] Alternatively, in another aspect of the present invention, in the above configuration, the electron transport material is as described in the first This is a light-emitting device in which the first skeleton and the third skeleton are connected via the second skeleton.

[0034] Alternatively, in another aspect of the present invention, in the above configuration, the LUMO in the electron transport material However, these light-emitting devices are mainly distributed within the aforementioned first framework.

[0035] Alternatively, in another aspect of the present invention, in the above configuration, the first skeleton is a nitrogen-containing condensation It is a light-emitting device containing an aromatic ring or a triazine ring.

[0036] Alternatively, in another aspect of the present invention, in the above configuration, the first skeleton is a nitrogen source of two or more nitrogen sources. It is a light-emitting device that has offspring.

[0037] Alternatively, in another aspect of the present invention, in the above configuration, the first skeleton is a quinoxaline ring , dibenzo[h,g]quinoxaline ring, triazine ring and benzoflopyrimidine ring It is a light-emitting device that has a framework that includes a differential.

[0038] Alternatively, in another aspect of the present invention, in the above configuration, the first skeleton is a quinoxaline ring It is a light-emitting device that forms the underlying framework.

[0039] Alternatively, in another aspect of the present invention, in the above configuration, the HOMO in the electron transport material However, these light-emitting devices are mainly distributed within the second framework described above.

[0040] Alternatively, in another aspect of the present invention, in the above configuration, the third skeleton has nitrogen atoms. This is a light-emitting device containing a six-membered heteroaromatic ring.

[0041] Alternatively, in another aspect of the present invention, in the above configuration, the third skeleton is a pyridine ring, It is a light-emitting device that is one of the following: a limidine ring, a pyrazine ring, or a triazine ring.

[0042] Alternatively, in another aspect of the present invention, in the above configuration, the third skeleton is the second skeleton The second skeleton is bonded to the carbon atom such that the β position relative to the bonded carbon is nitrogen. It is a device.

[0043] Alternatively, in another aspect of the present invention, in the above configuration, the third skeleton is replaced at position 3. This light-emitting device is a lysine ring, a pyrimidine ring substituted at the 5th position, or a pyrazine ring.

[0044] Alternatively, in another aspect of the present invention, in the above configuration, the electron transport layer is in contact with the cathode. It is a light-emitting device.

[0045] Alternatively, in another aspect of the present invention, in the above configuration, the light-emitting layer comprises a host material and light-emitting The device comprises a material, and the light-emitting material is a light-emitting device that emits blue fluorescence.

[0046] Alternatively, another aspect of the present invention is a light-emitting device as described above, and a sensor, an operating box It is an electronic device having a tongue, speaker, or microphone.

[0047] Alternatively, another aspect of the present invention is a light-emitting device as described above, and a transistor, Alternatively, it is a light-emitting device having a substrate.

[0048] Alternatively, another aspect of the present invention is a light-emitting device having a housing, the light-emitting device described in any of the above descriptions. It is a lighting device.

[0049] Alternatively, another aspect of the present invention comprises a first frame, a second frame, and a third frame, and A compound used in a electron transport layer, wherein the first skeleton has the function of transporting electrons, The second skeleton has the function of accepting holes, and the third skeleton is monocyclic and π-electron-inclusive. It is a compound that has a heteroaromatic ring with a foot-like structure.

[0050] In this specification, the term "light-emitting device" includes image display devices that use light-emitting devices. Also, connectors, such as anisotropic conductive film or TCP (Tape) may be attached to the light-emitting device. Module with Carrier Package attached, print to TCP A module equipped with a wiring board, or a light-emitting device, with COG (Chip On Glas Modules in which ICs (integrated circuits) are directly mounted using method s) may also be included as light-emitting devices. Yes, they do. Furthermore, lighting fixtures and the like may have light-emitting devices. [Effects of the Invention]

[0051] In one aspect of the present invention, a novel light-emitting device can be provided, or a device with a good lifespan. We can provide light-emitting devices. Or, we can provide light-emitting devices with good luminous efficiency. It is possible.

[0052] Alternatively, in another aspect of the present invention, a highly reliable light-emitting device, electronic device, and display device are provided, respectively. It can be provided. Or, in another aspect of the present invention, a light-emitting device with low power consumption, Electronic devices and display devices can be provided, respectively.

[0053] Furthermore, the description of these effects does not preclude the existence of other effects. The embodiment does not necessarily have to have all of these effects. Furthermore, other effects are... This will become clear from the description in the specification, drawings, claims, etc., and the specification, drawings Furthermore, it is possible to extract other effects from the descriptions in the claims and other documents. [Brief explanation of the drawing]

[0054] [Figure 1] Figures 1(A), 1(B), and 1(C) are schematic diagrams of light-emitting devices. [Figure 2] Figures 2(A) and 2(B) are conceptual diagrams of an active matrix type light-emitting device. [Figure 3] Figures 3(A) and 3(B) are conceptual diagrams of an active matrix type light-emitting device. [Figure 4] Figure 4 is a conceptual diagram of an active matrix type light-emitting device. [Figure 5] Figures 5(A) and 5(B) are diagrams representing lighting devices. [Figure 6] Figures 6(A), 6(B1), 6(B2), and 6(C) are diagrams representing electronic devices. [Figure 7] Figures 7(A), 7(B), and 7(C) are diagrams representing electronic devices. [Figure 8] Figure 8 is a diagram representing a lighting device. [Figure 9] Figure 9 is a diagram representing a lighting device. [Figure 10] Figure 10 shows an in-vehicle display device and lighting system. [Figure 11] Figures 11(A), 11(B), and 11(C) are diagrams representing electronic devices. [Figure 12] Figures 12(A) and 12(B) are diagrams representing electronic devices. [Figure 13] Figure 13 shows the luminance-current density characteristics of light-emitting device 1 and comparison light-emitting device 1. [Figure 14] Figure 14 shows the current efficiency-luminance characteristics of light-emitting device 1 and comparative light-emitting device 1. [Figure 15] Figure 15 shows the luminance-voltage characteristics of light-emitting device 1 and comparison light-emitting device 1. [Figure 16] Figure 16 shows the current-voltage characteristics of light-emitting device 1 and comparison light-emitting device 1. [Figure 17] Figure 17 shows the external quantum efficiency-luminance characteristics of light-emitting device 1 and comparative light-emitting device 1. [Figure 18] Figure 18 shows the emission spectra of light-emitting device 1 and comparison light-emitting device 1. [Figure 19] Figure 19 shows the normalized luminance-time variation characteristics of light-emitting device 1 and comparative light-emitting device 1. [Figure 20] Figure 20 shows the structure of the measuring element. [Figure 21] Figure 21 shows the current density-voltage characteristics of the measuring element. [Figure 22] Figure 22 shows the frequency characteristics of the calculated capacitance C in ZADN:Liq(1:1) at a DC voltage of 7.0V. [Figure 23] Figure 23 shows the frequency characteristics of ZADN:Liq(1:1) at a DC voltage of 7.0V with respect to -ΔB. [Figure 24] Figure 24 shows the electric field strength dependence characteristics of electron mobility in each organic compound. [Figure 25] Figures 25(A) and 25(B) show the 1H NMR spectra of BfpmPPyA. [Figure 26] Figures 26(A) and 26(B) show the 1H NMR spectra of DBqPPyA. [Figure 27] Figures 27(A) and 27(B) show the 1H NMR spectra of NfprPPyA. [Figure 28]Figure 28 shows the luminance-current density characteristics of light-emitting devices 2 to 4. [Figure 29] Figure 29 shows the current efficiency-luminance characteristics of light-emitting devices 2 to 4. [Figure 30] Figure 30 shows the luminance-voltage characteristics of light-emitting devices 2 to 4. [Figure 31] Figure 31 shows the current-voltage characteristics of light-emitting devices 2 to 4. [Figure 32] Figure 32 shows the external quantum efficiency-luminance characteristics of light-emitting devices 2 to 4. [Figure 33] Figure 33 shows the emission spectra of light-emitting devices 2 through 4. [Figure 34] Figure 34 shows the normalized luminance-time variation characteristics of light-emitting devices 2 to 4. [Modes for carrying out the invention]

[0055] The embodiments of the present invention will be described in detail below with reference to the drawings. However, the present invention is as follows Not limited to the description, the form and details thereof may be described without departing from the spirit and scope of the present invention. Those skilled in the art will readily understand that the invention can be modified in various ways. Therefore, the present invention is as follows: This should not be interpreted as being limited to the contents described in the embodiments.

[0056] (Embodiment 1) Figure 1(A) shows a diagram representing a light-emitting device according to one aspect of the present invention. The vice has an anode 101, a cathode 102, and an EL layer 103, and the EL layer is small It also has an emissive layer 113 and an electron transport layer 114.

[0057] In Figure 1(A), the EL layer 103, in addition to the light-emitting layer 113 and the electron transport layer 114, is The hole injection layer 111 and hole transport layer 112 are shown in the diagram, but the structure of the EL layer 103 is as follows: It is not limited. As shown in Figure 1(B), it may have an electron injection layer 115, or holes. The transport layer 112 has a first hole transport layer 112-1 and a second hole transport layer 112-2. It is also possible that the electron transport layer 114 is the first electron transport layer 114-1 and the second electron transport layer 1 It may have 14-2.

[0058] In one embodiment of the present invention, the electron transport material used in the electron transport layer 114 is It has a first skeleton, a second skeleton, and a third skeleton, each performing a different function.

[0059] The first framework is a framework that has the function of transporting electrons. Furthermore, the LUM of the electron transport material... O is mainly distributed in the first skeleton, and the electron transport capacity of this electron transport material is in the first skeleton It is derived from the grade. The first skeleton contains nitrogen in order to exhibit electron transport properties. It is preferable that the first skeleton is a condensed aromatic ring or a triazine skeleton. To distribute electrons (in other words, to increase the electron-accepting ability of the first skeleton and accept more electrons than the third skeleton) To make it easier to remove, the first skeleton contains two or more nitrogen atoms. Preferably, the two or more nitrogen atoms are located on a six-membered aromatic ring. Suitable skeletons for use as the first skeleton include a quinoxaline ring and a gibberellin ring. Examples include the quinoxaline ring, triazine ring, and benzoflopyrimidine ring. These can be, and among them, a skeleton containing a quinoxaline ring is preferred.

[0060] The second skeleton is a skeleton that has the function of receiving holes. Furthermore, the second skeleton has two or more rings. It is preferable that it be a condensed aromatic hydrocarbon ring. Also, in order to accept holes, a second bone The compound more preferably has three or more condensed aromatic hydrocarbon rings. The hydrogen rings are preferably six or fewer in order to maintain sublimation properties and appropriate solubility. From the standpoint of maintaining the energy gap, having four rings or less is preferable. However, if heat resistance is high In order to achieve this, the number of carbon atoms forming the ring of the condensed aromatic hydrocarbon ring must be 14 or more. Preferred. Also, considering stability in the excited state, the condensed aromatic hydrocarbon ring is 6 It is preferable that it consists only of member rings. Furthermore, it can be suitably used as a second skeleton. Examples of condensed aromatic hydrocarbon rings include naphthalene rings, fluorene rings, and anthracite rings. Cen ring, phenanthrene ring, benzofluorene ring, tetracene ring, chrysene ring, triphe Examples include nilen rings and pyrene rings. Among these, moderate hole-receptor capacity is particularly important. Anthracene rings are preferred because they provide chemical stability. Also, the second bone It is preferable that the HOMO of the electron transport material is distributed in the slate.

[0061] The third framework is a monocyclic, π-electron-deficient heteroaromatic ring, which provides electron injection from the cathode. It is preferable that the ring has a nitrogen atom in order to provide the desired properties. Specifically, pyridine A ring, pyrimidine ring, pyrazine ring, and triazine ring are preferred. When bonded to the skeleton, the third skeleton has a carbon bonded to the second skeleton. Preferably, the atom located at the β position is nitrogen. That is, the third skeleton is pi It is preferable that the ring is a radin ring, a pyridine ring substituted at position 3, or a pyrimidine ring substituted at position 5. This improves contact with the cathode, reducing the drive voltage at high brightness levels. This is the reason. Furthermore, because the third framework has this configuration, the electron transport layer 114 and the cathode Even without providing an electron injection layer between 102 and the device, a light-emitting device with good characteristics at a low drive voltage can be obtained. It can be obtained.

[0062] Furthermore, if the first and third skeletons are combined, there is a possibility that LUMOs will be distributed in both. Since this increases the likelihood of the problem occurring, it is preferable that these skeletons are connected via a second skeleton.

[0063] The light-emitting layer 113 has a host material and a light-emitting material. It may also contain other materials different from the luminescent material. It may also be a stack of two different layers.

[0064] Whether the light-emitting material is a fluorescent material or a phosphorescent material, it exhibits thermally activated delayed fluorescence (T It may be a material exhibiting ADF (Active Deposition Factor), or any other luminescent material. Also, it may be a single layer. However, it may consist of multiple layers. In one aspect of the present invention, the light-emitting layer 113 is fluorescent A layer that exhibits light emission is more preferable, particularly a layer that exhibits blue fluorescence emission.

[0065] In the light-emitting layer 113, possible materials that can be used as fluorescent light-emitting materials include, for example, 5,6-Bis[4-(10-phenyl-9-antryl)phenyl]-2,2'-bipyri Zin (abbreviation: PAP2BPy), 5,6-bis[4'-(10-phenyl-9-antri [Lu)biphenyl-4-yl]-2,2'-bipyridine (abbreviation: PAPP2BPy), N, N'-diphenyl-N,N'-bis[4-(9-phenyl-9H-fluoren-9-yl] )phenyl]pyrene-1,6-diamine (abbreviation: 1,6FLPAPrn), N,N'-bi Su(3-methylphenyl)-N,N'-bis[3-(9-phenyl-9H-fluorene- 9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6mMemFLPAPrn) ), N,N'-bis[4-(9H-carbazole-9-yl)phenyl]-N,N'-di Phenylstilbene-4,4'-diamine (abbreviation: YGA2S), 4-(9H-carbazo (Abbreviated) 4'-(10-phenyl-9-anthryl)triphenylamine ( Name: YGAPA), 4-(9H-carbazole-9-yl)-4'-(9,10-dife Nyl-2-anthryl)triphenylamine (abbreviation: 2YGAPPA), N,9-diphenyl Nyl-N-[4-(10-phenyl-9-antryl)phenyl]-9H-carbazole -3-amine (abbreviation: PCAPA), perylene, 2,5,8,11-tetra-tert- Butylperylene (abbreviation: TBP), 4-(10-phenyl-9-anthryl)-4'-( 9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBAP) A) N,N''-(2-tert-butylanthracene-9,10-diyldi-4,1 -phenylene)bis[N,N',N'-triphenyl-1,4-phenylenediamine]( Abbreviation: DPABPA), N,9-diphenyl-N-[4-(9,10-diphenyl-2- Anthryl)phenyl]-9H-carbazole-3-amine (abbreviation: 2PCAPPA), N-[4-(9,10-diphenyl-2-anthryl)phenyl]-N,N',N'-to Riphenyl-1,4-phenylenediamine (abbreviation: 2DPAPPA), N,N,N',N ',N'',N'',N''',N'''-Octaphenyldibenzo[g,p]chrysene -2,7,10,15-tetraamine (abbreviation: DBC1), coumarin 30, N-(9,1 0-Diphenyl-2-anthryl)-N,9-Diphenyl-9H-carbazole-3-A Min (abbreviation: 2PCAPA), N-[9,10-bis(1,1'-biphenyl-2-yl] )-2-anthryl]-N,9-diphenyl-9H-carbazole-3-amine (abbreviation: 2PCABPhA), N-(9,10-diphenyl-2-anthryl)-N,N',N' -Triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPA), N-[9,10 -Bis(1,1'-biphenyl-2-yl)-2-anthryl]-N,N',N'-tri Phenyl-1,4-phenylenediamine (abbreviation: 2DPABPhA), 9,10-bis( 1,1'-biphenyl-2-yl)-N-[4-(9H-carbazole-9-yl) [Nyl]-N-phenylanthracene-2-amine (abbreviation: 2YGABPhA), N,N, 9-Triphenylanthracene-9-amine (abbreviation: DPhAPhA), Coumarin 545 T,N,N'-diphenylquinacridone (abbreviation: DPQd), rubren, 5,12-bis (1,1'-biphenyl-4-yl)-6,11-diphenyltetracene (abbreviation: BPT) ), 2-(2-{2-[4-(dimethylamino)phenyl]ethenyl}-6-methyl-4 H-pyran-4-ylidene)propanedinitrile (abbreviation: DCM1), 2-{2-methyl -6-[2-(2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolidine] [-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: D CM2), N,N,N',N'-Tetrakis(4-methylphenyl)tetracene-5,1 1-Diamine (abbreviation: p-mPhTD), 7,14-diphenyl-N,N,N',N'- Tetrakis(4-methylphenyl)acenaphtho[1,2-a]fluorantene-3,10 -Diamine (abbreviation: p-mPhAFD), 2-{2-isopropyl-6-[2-(1,1 ,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij] [Quinoridine-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (Abbreviation: DCJTI), 2-{2-tert-butyl-6-[2-(1,1,7 Tramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolidine 9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DC JTB), 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-teto Lahydro-1H,5H-benzo[ij]quinoridine-9-yl)ethenyl]-4H-pyra N-4-ylidene propanedinitrile (abbreviation: BisDCJ™), N,N'-diphosphate Nyl-N,N'-(1,6-pyrene-diyl)bis[(6-phenylbenzo[b]naphthate [1,2-d]furan)-8-amine](abbreviation: 1,6BnfAPrn-03), 3,1 0-Bis[N-(9-phenyl-9H-carbazol-2-yl)-N-phenylamino ]Naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3,10PCA2Nb f(IV)-02), 3,10-bis[N-(dibenzofuran-3-yl)-N-phenyl Luamino]naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3,10Fr Examples include A2Nbf(IV)-02). In particular, 1,6FLPAPrn and 1,6m Pyridine compounds such as MemFLPAPrn and 1,6BnfAPrn-03 can be substituted. The condensed aromatic diamine compounds shown exhibit high hole-trapping properties and excellent luminescence efficiency and reliability. This is preferable because it is well-maintained.

[0066] In the light-emitting layer 113, when a phosphorescent material is used as the light-emitting central material, Possible materials include, for example, Tris{2-[5-(2-methylphenyl)-4-(2, [6-dimethylphenyl)-4H-1,2,4-triazole-3-yl-κN2]phenyl Iridium(III) (abbreviation: [Ir(mpptz-dmp)3]), Tris (5-methyl-3,4-diphenyl-4H-1,2,4-triazolato)iridium(I II) (abbreviation: [Ir(Mptz)3]), Tris[4-(3-biphenyl)-5-iso [Propyl-3-phenyl-4H-1,2,4-triazolato]iridium(III) (abbreviated) Name: Organic compounds with a 4H-triazole skeleton, such as [Ir(iPrptz-3b)3]) Metallic iridium complexes and tris[3-methyl-1-(2-methylphenyl)-5-phenyl [Ir-1H-1,2,4-Triazolat] Iridium(III) (Abbreviation: [Ir(Mptz 1-mp)3]), Tris(1-methyl-5-phenyl-3-propyl-1H-1,2, 4-Triazolat) Iridium(III) (Abbreviation: [Ir(Prptz1-Me)3]) organometallic iridium complexes having a 1H-triazole skeleton, such as fac-tris[ 1-(2,6-diisopropylphenyl)-2-phenyl-1H-imidazole]iridi Um(III) (abbreviation: [Ir(iPrpmi)3]), Tris[3-(2,6-Dimethicone] Iridium (I)-7-methylimidazo[1,2-f]phenantridinato]iridium II) (Abbreviation: [Ir(dmpimpt-Me)3]) has an imidazole skeleton organometallic iridium complexes and bis[2-(4',6'-difluorophenyl)pyridina To-N,C 2’ Iridium(III) tetrakis(1-pyrazolyl) borate (abbreviation: FIr6), bis[2-(4',6'-difluorophenyl)pyridinate-N,C 2’ ] 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’ Iridium(III) acetylacetate Phenylpyridine derivatives with electron-withdrawing groups, such as tonat (abbreviated as Fir(acac)), are involved. Examples include organometallic iridium complexes with conductor ligands. These exhibit blue phosphorescence. The compound shown has an emission peak between 440 nm and 520 nm.

[0067] Furthermore, as a material that can be used for the light-emitting layer 113, tris(4-methyl-6-pheny Lupirimidinatus iridium(III) (abbreviation: [Ir(mppm)3]), Tris(4 Iridium(III) (abbreviation: [Ir(tB)-t-butyl-6-phenylpyrimidinato) uppm)3]), (acetylacetonato)bis(6-methyl-4-phenylpyrimidina Iridium(III) (abbreviation: [Ir(mppm)2(acac)]), (acetyl Acetonato)bis(6-tert-butyl-4-phenylpyrimidinato)iridium(I II) (Abbreviation: [Ir(tBuppm)2(acac)]), (Acetylacetonate)bi S[6-(2-norbornyl)-4-phenylpyrimidinato]iridium(III) (abbreviated) Name: [Ir(nbppm)2(acac)]), (acetylacetonato)bis[5-meth Lu-6-(2-methylphenyl)-4-phenylpyrimidinato]iridium(III)( Abbreviation: [Ir(mpmppm)2(acac)]), (acetylacetonato)bis(4, 6-Diphenylpyrimidinato) Iridium(III) (Abbreviation: [Ir(dppm)2(a Organometallic iridium complexes having a pyrimidine skeleton such as (cac)), and (acetylated iridium complexes). Setonato)bis(3,5-dimethyl-2-phenylpyradinate)iridium(III) Abbreviation: [Ir(mppr-Me)2(acac)]), (acetylacetonato)bis(5 -Isopropyl-3-methyl-2-phenylpyradinato) Iridium(III) (abbreviation: Organometallic compounds with a pyrazine skeleton, such as [Ir(mppr-iPr)2(acac)]). iridium complexes and tris(2-phenylpyridinato-N,C) 2’ ) Iridium (III ) (Abbreviation: [Ir(ppy)3]), bis(2-phenylpyridinato-N,C) 2’ ) Iri Dium(III) acetylacetonate (abbreviation: [Ir(ppy)2(acac)]), Bis(benzo[h]quinolinate)iridium(III)acetylacetonate (abbreviation: [ Ir(bzq)2(acac)]), Tris(benzo[h]quinolinate) Iridium(I II) (Abbreviation: [Ir(bzq)3]), Tris(2-phenylquinolinato-N,C) 2’ Iridium(III) (abbreviation: [Ir(pq)3]), bis(2-phenylquinolinate) -N,C 2’ ) Iridium(III) acetylacetonate (abbreviation: [Ir(pq)2( In addition to organometallic iridium complexes with a pyridine skeleton such as acac), Tris(A Cetylacetonate) (monophenanthroline) terbium(III) (abbreviation: [Tb(a Examples include rare earth metal complexes such as cac)3(Phen)]). These are mainly green This compound exhibits phosphorescence and has an emission peak in the 500nm to 600nm range. Organometallic iridium complexes with a pyrimidine skeleton are also outstanding in terms of reliability and luminescence efficiency. Therefore, it is particularly preferable.

[0068] Furthermore, (diisobutylylmethanato)bis is a material that can be used for the light-emitting layer 113. [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(5md ppm)2(dpm)]), bis[4,6-di(naphthalene-1-yl)pyrimidinato] (Dipivaloylmethanato) Iridium(III) (Abbreviation: [Ir(d1npm)2(dp Organometallic iridium complexes having a pyrimidine skeleton such as (m)), and (acetylacet Nato)bis(2,3,5-triphenylpyradinato)iridium(III) (abbreviation: [I r(tppr)2(acac)]), bis(2,3,5-triphenylpyradinate)(di Pivaloylmethanato)iridium(III) (abbreviation: [Ir(tppr)2(dpm)]) ), (acetylacetonato)bis[2,3-bis(4-fluorophenyl)quinoxalina to]iridium(III) (abbreviation: [Ir(Fdpq)2(acac)]) and other pyr idine skeleton-containing organometallic iridium complexes, tris(1-phenylisoquinolinato-N ,C 2’ )iridium(III) (abbreviation: [Ir(piq)3]), bis(1-phenyl isoquinolinato-N,C 2’ )iridium(III) acetylacetonate (abbreviation: [I r(piq)2(acac)]) and other pyridine skeleton-containing organometallic iridium complexes In addition to these, platinum complexes such as 2,3,7,8,12,13,17,18-octaethyl-21H,23H-por phyrin platinum(II) (abbreviation: PtOEP), and rare earth metal complexes such as tris(1,3-dif enyl-1,3-propanedionato)(monophenanthroline)europium(III) (abbreviation: [Eu(DBM)3(Phen)]), tris[1-(2-thenoyl)-3,3 ,3-trifluoroacetonato](monophenanthroline)europium(III) (abbre viation: [Eu(TTA)3(Phen)]) can be mentioned. These are compounds that exhibit red phosphorescent emission and have an emission peak at 600 nm to 700 nm . Also, organometallic iridium complexes having a pyrazine skeleton can obtain red emission with good chromaticity .

[0069] In addition to the phosphorescent compounds described above, known phosphorescent luminescent materials can also be selected and used .

[0070] As TADF materials, fullerenes and their derivatives, acridines and their derivatives, eosin Derivatives can be used. Also, magnesium (Mg), zinc (Zn), cadmium (Cd), tin (Sn), platinum (Pt), indium (In), or palladium (P Examples of metal-containing porphyrins include those described in d). For example, the protoporphyrin-tin fluoride complex (SnF2(Pro to IX), mesoporphyrin-tin fluoride complex (SnF2(Meso IX)), Hematoporphyrin-tin fluoride complex (SnF2(Hemato IX)), copropol Filinetetramethyl ester-tin fluoride complex (SnF2(Copro III-4M) e) Octaethylporphyrin-tin fluoride complex (SnF2(OEP)), ethiopropyl Rufirin-tin fluoride complex (SnF2(Etio I)), octaethylporphyrin - Examples include platinum chloride complexes (PtCl2OEP), etc.

[0071] [ka]

[0072] Furthermore, the following structural formula shows 2-(biphenyl-4-yl)-4,6-bis(12-) Enylindoro[2,3-a]carbazole-11-yl)-1,3,5-triazine( Abbreviations: PIC-TRZ) and 9-(4,6-diphenyl-1,3,5-triazine-2- Il)-9'-phenyl-9H,9'H-3,3'-bicarbazole (abbreviation: PCCzT) Zn), 9-[4-(4,6-diphenyl-1,3,5-triazine-2-yl)phenyl [Lu]-9'-phenyl-9H,9'H-3,3'-bicarbazole (abbreviation: PCCzPT) Zn), 2-[4-(10H-phenoxazine-10-yl)phenyl]-4,6-diph Phenyl-1,3,5-triazine (abbreviation: PXZ-TRZ), 3-[4-(5-phenyl -5,10-dihydrophenazine-10-yl)phenyl]-4,5-diphenyl-1, 2,4-Triazole (abbreviation: PPZ-3TPT), 3-(9,9-dimethyl-9H-A Cryzin-10-yl)-9H-xanthen-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 π-electron-rich heteroaromatic rings such as '-anthracene]-10'-one (abbreviated as ACRSA) Heterocyclic compounds having one or both of the π-electron-deficient heteroaromatic rings can also be used. The heterocyclic compound has a π-electron-rich heteroaromatic ring and a π-electron-deficient heteroaromatic ring. It is preferable because it has high electron transport and hole transport properties. In particular, the π-electron-deficient heteroaromatic ring is Among the skeletons it possesses, pyridine skeleton, diazine skeleton (pyrimidine skeleton, pyrazine skeleton, pyr The dazine skeleton and the triazine skeleton are preferred because they are stable and reliable. In particular, Benzoflopyrimidine skeleton, benzothienopyrimidine skeleton, benzoflopyrazine skeleton, ben The zothienopyrazine skeleton is preferred because it has high acceptability and good reliability. Also, π Among skeletons having electron-excess heteroaromatic rings, the acridine skeleton, the phenoxazine skeleton, and fu The phenothiazine skeleton, furan skeleton, thiophene skeleton, and pyrrole skeleton are stable and reliable. For the sake of being good, it is preferable to have at least one of the skeletons. The dibenzofuran skeleton is used for the thiophene skeleton, and the dibenzothiophene skeleton is used for the thiophene skeleton, respectively. Preferred. Also, as pyrrole skeletons, indole skeletons, carbazole skeletons, indole Carbazole skeleton, bicarbazole skeleton, 3-(9-phenyl-9H-carbazole-3) The -yl)-9H-carbazole skeleton is particularly preferred. Substances in which electron-deficient heteroaromatic rings are directly bonded to π-electron-rich heteroaromatic rings have electron-donating properties. The electron-accepting ability of π-electron-deficient heteroatomous rings increases, and the energies of the S1 and T1 levels change. This is particularly preferable because the difference becomes smaller, allowing for efficient acquisition of thermally activated delayed fluorescence. Instead of a π-electron-deficient heteroaromatic ring, an aromatic ring with an electron-withdrawing group such as a cyano group attached is used. They may also be used. In addition, aromatic amine skeletons, phenazine skeletons, etc. can be used as π-electron-rich skeletons. It can be used. In addition, xanthene skeletons and thioxanthene skeletons can be used as π-electron-deficient skeletons. Dioxide skeleton, oxadiazole skeleton, triazole skeleton, imidazole skeleton, Traquinone skeleton, boron-containing skeletons such as phenylborane and volanthrene, benzonitrile and These include aromatic rings or heteroaromatic rings having nitrile or cyano groups such as cyanobenzene, and benzobenzene. Carbonyl skeletons such as phenones, phosphine oxide skeletons, sulfone skeletons, etc. can be used. In this way, at least of the π-electron-deficient heteroaromatic ring and the π-electron-excess heteroaromatic ring Instead of one, a π-electron-deficient skeleton and a π-electron-excess skeleton can be used.

[0073] [ka]

[0074] TADF materials are characterized by a small difference between the S1 and T1 levels, and triple intersystem crossing occurs due to reverse intersystem crossing. A function that can convert energy from singlet excitation energy to singlet excitation energy. It is a material that possesses this property. Therefore, the triplet excitation energy is obtained by a small amount of thermal energy. Upconversion to the multiplet excitation energy (reverse intersystem crossing) is possible, and the singlet excited state can be efficiently converted. It can be generated easily. Furthermore, the triplet excitation energy can be converted into luminescence. .

[0075] Furthermore, an excited complex (exciplex) is formed by two different substances forming an excited state. Exciplex (also called 'x' or 'exciplex') is a state where the difference between the S1 level and the T1 level is extremely small. As a TADF material capable of converting triplet excitation energy to singlet excitation energy, It has the function of being functional.

[0076] Furthermore, phosphorescence observed at low temperatures (e.g., 77K to 10K) can be used as an indicator of the T1 level. A vector can be used. For TADF materials, the short-wavelength tail of its fluorescence spectrum is Draw a tangent line, and set the energy at the wavelength of the extrapolation line as the S1 level, and the phosphorescence spectrum When a tangent is drawn at the tail on the short wavelength side, and the energy at the wavelength of the extrapolation is taken as the T1 level, Preferably, the difference between S1 and T1 is 0.3 eV or less, and preferably 0.2 eV or less. And is even more preferable.

[0077] Furthermore, when using TADF material as the luminescence center material, the S1 level of the host material is TADF. It is preferable that the S1 level of the material is higher than the T level of the host material. Also, the T1 level of the host material is higher than the T level of the TADF material. It is preferable that the level is higher than level 1.

[0078] The host material for the light-emitting layer may be an electron-transporting material or a hole-transporting material, or the above Various carrier transport materials, such as TADF materials, can be used.

[0079] Materials with hole transport properties that can be used as host materials include amine skeletons and π Organic compounds having an electron-rich heteroaromatic ring skeleton are preferred. For example, 4,4'-bis[N -(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB), N,N'-bi Su(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4 '-diamine (abbreviation: TPD), 4,4'-bis[N-(spiro-9,9'-bifluore [N-2-yl)-N-phenylamino]biphenyl (abbreviation: BSPB), 4-phenyl- 4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP) ), 4-phenyl-3'-(9-phenylfluoren-9-yl)triphenylamine ( Abbreviation: mBPAFLP), 4-phenyl-4'-(9-phenyl-9H-carbazole- 3-yl)triphenylamine (abbreviation: PCBA1BP), 4,4'-diphenyl-4' '-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PC) BBi1BP), 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), 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] Aromatic amino acids such as spiro-9,9'-bifluoren-2-amine (abbreviation: PCBASF) Compounds with a 1,3-skeleton skeleton, and 1,3-bis(N-carbazolyl)benzene (abbreviation: mCP) , 4,4'-di(N-carbazolyl)biphenyl (abbreviation: CBP), 3,6-bis(3, 5-diphenylphenyl)-9-phenylcarbazole (abbreviation: CzTP), 3,3'- Carbazole skeletons such as bis(9-phenyl-9H-carbazole) (abbreviation: PCCP) Compounds containing, or 4,4',4''-(benzene-1,3,5-triyl)tri(dibe (Abbreviation: DBT3P-II), 2,8-diphenyl-4-[4-(9- Phenyl-9H-fluoren-9-yl)phenyl]dibenzothiophene (abbreviation: DBT) FLP-III), 4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl Thiophenicols such as ]-6-phenyldibenzothiophene (abbreviation: DBTFLP-IV) Compounds having a specific characteristic, or 4,4',4''-(benzene-1,3,5-triyl)tri(di Benzofuran) (abbreviation: DBF3P-II), 4-{3-[3-(9-phenyl-9H- Fluoren-9-yl)phenyl]phenyl}dibenzofuran (abbreviation: mmDBFFLB) Examples include compounds having a furan skeleton such as i-II). Among those mentioned above, aromatic ami Compounds with a carbazole skeleton or a carbazole skeleton have good reliability, and Furthermore, it is preferable because it has high hole transport properties and contributes to reducing the driving voltage. It can also be used in the following composite materials. As an example of an organic compound that possesses hole transport properties, hole transport materials can also be used. Cut.

[0080] Examples of electron-transporting materials that can be used as host materials include bis( 10-Hydroxybenzo[h]quinolinato)beryllium(II) (abbreviation: BeBq2), Bis(2-methyl-8-quinolinolate)(4-phenylphenolate)aluminum(II) I) (abbreviation: BAlq), bis(8-quinolinolato)zinc(II) (abbreviation: Znq), bi Su[2-(2-benzoxazolyl)phenolate]zinc(II) (abbreviation: ZnPBO), Bis[2-(2-benzothiazolyl)phenolate]zinc(II) (abbreviation: ZnBTZ) Any metal complex or organic compound having a π-electron-deficient heteroaromatic ring skeleton is preferred. Examples of organic compounds having a foot-shaped heteroaromatic ring skeleton include 2-(4-biphenylyl)- 5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD) ), 3-(4-biphenylyl)-4-phenyl-5-(4-tert-butylphenyl) -1,2,4-triazole (abbreviation: TAZ), 1,3-bis[5-(p-tert-br [Tylphenyl)-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), 2,2',2''-(1,3,5-bence Tris(1-phenyl-1H-benzoimidazole) (abbreviation: TPBI), 2-[3-(dibenzothiophen-4-yl)phenyl]-1-phenyl-1H-benzo Heterocyclization of polyazole skeletons such as imidazole (abbreviation: mDBTBIm-II) Compounds and 2-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h] Noxaline (abbreviation: 2mDBTPDBq-II), 2-[3'-(dibenzothiophene- [4-yl]biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBT) BPDBq-II), 2-[3'-(9H-carbazol-9-yl)biphenyl-3- Ildibenzo[f,h]quinoxaline (abbreviation: 2mCzBPDBq), 4,6-bis[ 3-(phenanthren-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm) ), 4,6-bis[3-(4-dibenzothienyl)phenyl]pyrimidine (abbreviation: 4,6 Heterocyclic compounds having a diazine skeleton such as mDBTP2Pm-II, and 3,5-bis[ 3-(9H-carbazole-9-yl)phenyl]pyridine (abbreviation: 35DCzPPy) , 1,3,5-tri[3-(3-pyridyl)phenyl]benzene (abbreviation: TmPyPB) Examples include heterocyclic compounds having a pyridine skeleton, such as the diazine skeleton. Heterocyclic compounds having a pyridine skeleton or heterocyclic compounds having a pyridine skeleton are preferred due to their good reliability. In particular, heterocyclic compounds with a diazine (pyrimidine or pyrazine) skeleton are involved in electron transport. It offers high performance and contributes to reducing the drive voltage.

[0081] As for TADF materials that can be used as host materials, the previously mentioned TADF materials are... The same material can be used. When TADF material is used as the host material, TA The triplet excitation energy generated in the DF material is converted to a singlet excitation energy through reverse intersystem crossing. This is converted to a different material, and then energy is transferred to the light-emitting central material, thereby improving the luminescence efficiency of the light-emitting device. This can enhance the emission. At this time, the TADF material functions as an energy donor and emits light. The central substance functions as an energy acceptor.

[0082] This is very effective when the above-mentioned luminescence center material is a fluorescent material. In order to obtain high luminescence efficiency, the S1 level of the TADF material is the same as the S1 level of the fluorescent material. It is preferable that the T1 level of the TADF material is higher than the S1 level of the fluorescent material. A higher level is preferable. Therefore, the T1 level of the TADF material is the T1 level of the fluorescent material. A level higher than the current level is preferable.

[0083] Furthermore, T exhibits emission that overlaps with the wavelength of the lowest energy absorption band of the fluorescent material. It is preferable to use ADF material. This allows the fluorescent material to be converted from TADF material. This is preferable because it allows for smoother transfer of excitation energy and efficient emission.

[0084] Furthermore, singlet excitation energy is efficiently generated from triplet excitation energy through reverse intersystem crossing. For this to occur, it is preferable that carrier recombination occurs in the TADF material. The triplet excitation energy generated by the DF material is transferred to the triplet excitation energy of the fluorescent material. It is preferable not to do so. To that end, the fluorescent material has a luminescent phosphodiolus ( It is preferable to have a protecting group around the skeleton that causes light emission. The protecting group is a π bond. Substituents that do not have a substituent are preferred, saturated hydrocarbons are preferred, specifically those having 3 to 10 carbon atoms. The alkyl group below, substituted or unsubstituted cycloalkyl groups with 3 to 10 carbon atoms, carbon Examples include trialkylsilyl groups with a number between 3 and 10, and it is even preferable if there are multiple protecting groups. Substituents that do not have a π bond have poor carrier transport function, therefore carrier transport and The distance between the TADF material and the fluorescent material's luminescent phosphate is minimized without affecting carrier recombination. It can keep the distance away. Here, a luminescent group is the substance that causes light emission in a fluorescent substance. This refers to an atomic group (skeleton). The luminescent group preferably has a skeleton with π bonds and contains an aromatic ring. It is preferable that it has a condensed aromatic ring or a condensed heteroaromatic ring. Examples of compound aromatic rings include the phenanthrene skeleton, stilbene skeleton, acridone skeleton, and pheno Examples include xazine skeletons and phenothiazine skeletons. In particular, naphthalene skeletons and anthracene skeletons. Skeleton, fluorene skeleton, chrysene skeleton, triphenylene skeleton, tetracene skeleton, pyrene skeleton It has a perylene skeleton, coumarin skeleton, quinacridone skeleton, and naphthobisbenzofuran skeleton. Fluorescent materials are preferred because they have a high fluorescence quantum yield.

[0085] When using a fluorescent material as the luminescent center material, the host material is an anthracene skeleton. Materials having an anthracene skeleton are preferred as host materials for fluorescent materials. When used in this way, it is possible to realize a light-emitting layer with good luminescence efficiency and durability. As for materials that have an anthracene skeleton, diphenylanthracene skeleton Because substances, especially those with a 9,10-diphenylanthracene skeleton, are chemically stable. It is preferable. Furthermore, if the host material has a carbazole skeleton, the hole injection and transport properties are high. This is preferable, but benzocarbazole bone is formed when a benzene ring is further condensed on carbazole. When a positive charge is present, the HOMO becomes about 0.1 eV shallower than that of carbazole, making it easier for holes to enter. This is preferable because it makes the host material less likely to cause problems. In particular, when the host material contains a dibenzocarbazole skeleton, The HOMO is about 0.1 eV shallower than that of Luvazole, making it easier for holes to enter, and It is suitable because it has excellent transportability and high heat resistance. Therefore, as a host material Preferably, the 9,10-diphenylanthracene skeleton and the carbazole skeleton ( These are substances that simultaneously possess a benzocarbazole skeleton or a dibenzocarbazole skeleton. Furthermore, from the viewpoint of hole injection and transport as described above, the carbazole skeleton has been replaced with benzofluorescein. A 9-fluorene skeleton or a dibenzofluorene skeleton may also be used. An example of such a substance is 9-fluorene. phenyl-3-[4-(10-phenyl-9-antryl)phenyl]-9H-carbazole PCzPA (abbreviation: PCzPA), 3-[4-(1-naphthyl)-phenyl]-9-phenyl-9 H-carbazole (abbreviation: PCPN), 9-[4-(10-phenyl-9-anthraceni [Phenyl]-9H-carbazole (abbreviation: CzPA), 7-[4-(10-phenyl] -9-Anthryl)phenyl]-7H-dibenzo[c,g]carbazole (abbreviation: cgD BCzPA), 6-[3-(9,10-diphenyl-2-anthryl)phenyl]-ben Zo[b]naphtho[1,2-d]furan (abbreviation: 2mBnfPPA), 9-phenyl-10 -{4-(9-phenyl-9H-fluoren-9-yl)biphenyl-4'-yl}an Tracene (abbreviation: FLPPA), 9-(1-naphthyl)-10-[4-(2-naphthyl) Examples include phenylanthracene (abbreviation: BH513), and in particular, CzPA and cgD BCzPA, 2mBnfPPA, and PCzPA exhibit very good characteristics, making them preferred choices. It is a choice.

[0086] Furthermore, the host material may be a mixture of multiple substances, and the mixed host material When used, a mixture of electron-transporting material and hole-transporting material is used. Preferably, by mixing an electron-transporting material with a hole-transporting material. , the transportability of the light-emitting layer 113 can be easily adjusted, and the control of the recombination region can also be easily performed. This is possible. The weight ratio of the content of the material having hole transportability to the material having electron transportability may be hole transportable material: electron transportable material = 1:19 to 19:1.

[0087] In addition, as part of the above mixed materials, a phosphorescent substance can be used. The phosphorescent substance can be used as an energy donor that supplies excitation energy to the fluorescent substance when the fluorescent substance is used as the light-emitting center material.

[0088] Also, an exciplex may be formed between these mixed materials. The exciplex forms an exciplex that exhibits light emission overlapping with the wavelength of the absorption band on the lowest energy side of the light-emitting material. By selecting a combination that can achieve this, energy transfer becomes smooth and efficient light emission can be obtained, which is preferable. Also, since the driving voltage is reduced by using this configuration, it is preferable.

[0089] Note that at least one of the materials forming the exciplex may be a phosphorescent substance. By doing so, triplet excitation energy can be efficiently converted into singlet excitation energy by reverse intersystem crossing.

[0090] As a combination of materials that can efficiently form an exciplex, it is preferable that the HOMO level of the material having hole transportability is higher than the HOMO level of the material having electron transportability. Also, it is preferable that the LUMO level of the material having hole transportability is higher than the LUMO level of the material having electron transportability. The LUMO level and HOMO level of the material are measured by cyclic voltammetry. ​​​​​​​From the electrochemical properties (reduction potential and oxidation potential) of the material measured by CV (coefficient of variation) It can be derived.

[0091] Furthermore, the formation of excited complexes is related to, for example, the emission spectrum of hole-transporting materials and electron-transporting properties. The emission spectrum of a material having the above properties, and the emission spectrum of a mixed film obtained by mixing these materials. In comparison, the emission spectrum of the mixed film is shifted to longer wavelengths than the emission spectra of each individual material. Alternatively, this can be confirmed by observing a phenomenon (which has a new peak on the longer wavelength side). Alternatively, transient photoluminescence (PL) and electron transport of materials with hole transport properties. The transient PL of materials possessing certain properties and the transient PL of a mixed film obtained by mixing these materials are compared, and the mixing The transient PL lifetime of the film has a longer lifetime component than the transient PL lifetime of each material, or a delayed lifetime component. This can be confirmed by observing differences in transient responses, such as an increase in the proportion of the time. Furthermore, the transient PL mentioned above can be interpreted as transient electroluminescence (EL). No. That is, transient EL for hole-transporting materials, transient E for electron-transporting materials. By comparing the transient EL of L and mixed films and observing the differences in transient response, Excitation complex formation can be confirmed.

[0092] A light-emitting device according to one aspect of the present invention having the above configuration is a reliable light-emitting device This allows for the creation of a light-emitting device with a small slope in its degradation curve, and in particular, one that exhibits suppressed long-term degradation. It can be made into S.

[0093] Next, we will explain other layers that can be used in the EL layer 103.

[0094] The hole injection layer 111 is a layer designed to facilitate the injection of holes into the EL layer 103, and hole injection It is constructed using highly durable materials. The hole injection layer 111 is composed solely of an acceptor material. It may be done, but it may contain an acceptor substance and an organic compound that has hole-transporting properties. It is preferable that it be composed of composite materials.

[0095] Acceptor substances are organic compounds with hole-transporting properties contained in hole transport layers or hole injection layers. It is a substance that exhibits electron-accepting properties towards other materials.

[0096] Both inorganic and organic compounds can be used as acceptor substances. However, organic compounds having electron-withdrawing groups (especially halogen groups such as fluoro groups or cyano groups) It is preferable to use such substances. Accepting substances are selected from among such substances for hole transport. Substances that exhibit electron-accepting properties for hole-transporting organic compounds contained in layers or hole-injection layers. You can select the appropriate option.

[0097] Examples of such acceptor-like substances include 7,7,8,8-tetracyano-2, 3,5,6-Tetrafluoroquinodimethane (abbreviation: F4-TCNQ), chloranil, 2, 3,6,7,10,11-Hexacyano-1,4,5,8,9,12-Hexaazatlif Enilen (abbreviation: HAT-CN), 1,3,4,5,7,8-hexafluorotetrasia No-naphthoxinodimethane (abbreviation: F6-TCNNQ), 2-(7-dicyanomethylene-1) ,3,4,5,6,8,9,10-Octafluoro-7H-pyrene-2-ylidene)malo Examples include nonitriles, and in particular, those containing multiple complex atoms, such as HAT-CN. Compounds in which an electron-withdrawing group is bonded to a condensed aromatic ring are thermally stable and preferred. Radialene derivatives having a sub-attracting group (especially a halogen group such as a fluoro group or a cyano group) are preferable because of their very high electron-accepting properties. Specifically, α,α’,α’’-1,2, 3-cyclopropanetriylidene tris[4-cyano-2,3,5,6-tetrafluorobenzeneacetonitrile], α,α’,α’’-1,2,3-cyclopropanetriylidene tris [2,6-dichloro-3,5-difluoro-4-(trifluoromethyl)benzeneacetonitrile], α,α’,α’’-1,2,3-cyclopropanetriylidene tris [2,3,4,5,6-pentafluorobenzeneacetonitrile] and other organic compounds can be mentioned. When the acceptor substance is an inorganic compound, transition metal oxides can also be used. Particularly, oxides of metals belonging to Groups 4 to 8 in the periodic table are suitable. Examples of the oxides of metals belonging to Groups 4 to 8 in the periodic table include vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, molybdenum oxide, tungsten oxide, manganese oxide, rhenium oxide, etc., which are preferable due to their high electron-accepting properties. Among them, molybdenum oxide is preferable because it is stable in the atmosphere, has low hygroscopicity, and is easy to handle. The organic compound having hole-transporting properties used in the composite material is a hole-transporting material, and it preferably has a relatively deep HOMO level with a HOMO level of -5.7 eV or more and -5.4 eV or less. When the organic compound having hole-transporting properties used in the composite material has a relatively deep HOMO level, the induction of holes is moderately suppressed. On the other hand, the injection of the induced holes into the hole-transporting layer 112 becomes easy.

[0098]

[0099] Examples of hole-transporting organic compounds used in composite materials include carbazole skeletons and gibberellin. It has one of the following skeletons: zofuran skeleton, dibenzothiophene skeleton, or anthracene skeleton. It is more preferable to have substitutions including a dibenzofuran ring or a dibenzothiophene ring. Aromatic amines having a group, aromatic monoamines having a naphthalene ring are preferred, or 9 - An aromatic monoamine in which a fluorenyl group is bonded to the nitrogen of the amine via an arylene group. It is also acceptable if these substances have an N,N-bis(4-biphenyl)amino group. Using a material is preferable because it allows for the creation of light-emitting devices with a good lifespan. Examples of such substances include 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 n (abbreviation: BBABnf), 4,4'-bis(6-phenylbenzo[b]naphtho[1,2 -d]Fran-8-yl)-4''-phenyltriphenylamine (abbreviation: BnfBB1) BP), 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: BB) ABnf(II)(4)), N,N-bis[4-(dibenzofuran-4-yl)phenyl ]-4-amino-p-terphenyl (abbreviation: DBfBB1TP), N-[4-(dibenzo Thiophen-4-yl)phenyl]-N-phenyl-4-biphenylamine (abbreviation: Th BA1BP), 4-(2-naphthyl)-4',4''-diphenyltriphenylamine ( Abbreviation: BBAβNB), 4-[4-(2-naphthyl)phenyl]-4',4''-diphenyl Nyltriphenylamine (abbreviation: BBAβNBi), 4,4'-diphenyl-4''-( 6;1'-Binaphthyl-2-yl)triphenylamine (abbreviation: BBAαNβNB), 4 ,4'-diphenyl-4''-(7;1'-binaphthyl-2-yl)triphenylamine (Abbreviation: BBAαNβNB-03), 4,4'-diphenyl-4''-(7-phenyl) Naphthyl-2-yltriphenylamine (abbreviation: BBAPβNB-03), 4,4'-di Phenyl-4''-(6;2'-binaphthyl-2-yl)triphenylamine (abbreviation: B BA(βN2)B), 4,4'-diphenyl-4''-(7;2'-binaphthyl-2-I (L) Triphenylamine (abbreviation: BBA(βN2)B-03), 4,4'-diphenyl- 4''-(4;2'-binaphthyl-1-yl)triphenylamine (abbreviation: BBAβNα) NB), 4,4'-diphenyl-4''-(5;2'-binaphthyl-1-yl)triphen Nylamine (abbreviation: BBAβNαNB-02), 4-(4-biphenylyl)-4'-(2 -Naphthyl)-4''-phenyltriphenylamine (abbreviation: TPBiAβNB), 4- (3-biphenylyl)-4'-[4-(2-naphthyl)phenyl]-4''-phenyl Riphenylamine (abbreviation: mTPBiAβNBi), 4-(4-biphenylyl)-4'- [4-(2-naphthyl)phenyl]-4''-phenyltriphenylamine (abbreviation: TP) BiAβNBi), 4-phenyl-4'-(1-naphthyl)triphenylamine (abbreviation: αNBA1BP), 4,4'-bis(1-naphthyl)triphenylamine (abbreviation: αNB) B1BP), 4,4'-diphenyl-4''-[4'-(carbazole-9-yl)bif [phenyl-4-yl]triphenylamine (abbreviation: YGTBi1BP), 4'-[4-(3 -phenyl-9H-carbazole-9-yl)phenyl]tris(1,1'-biphenyl -4-yl)amine (abbreviation: YGTBi1BP-02), 4-diphenyl-4'-(2- Naphthyl)-4''-{9-(4-biphenylyl)carbazole)}triphenylamine (Abbreviation: YGTBiβNB), N-[4-(9-phenyl-9H-carbazole-3-I) [4-(1-naphthyl)phenyl]-N-[4-(1-naphthyl)phenyl]-9,9'-spirobio(9H- Fluorene)-2-amine (abbreviation: PCBNBSF), N,N-bis(4-biphenylyl) )-9,9'-spirobio[9H-fluorene]-2-amine (abbreviation: BBASF), N, N-bis(1,1'-biphenyl-4-yl)-9,9'-spirobio[9H-fluorene ]-4-amine (abbreviation: BBASF(4)), N-(1,1'-biphenyl-2-yl) -N-(9,9-dimethyl-9H-fluoren-2-yl)-9,9'-spirobio(9H -Fluorene)-4-amine (abbreviation: oFBiSF), N-(4-biphenyl)-N-( Dibenzofuran-4-yl)-9,9-dimethyl-9H-fluoren-2-amine (abbreviation) :FrBiF), N-[4-(1-naphthyl)phenyl]-N-[3-(6-phenyldi Benzofuran-4-yl)phenyl]-1-naphthylamine (abbreviation: mPDBfBNBN ), 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine ( Abbreviation: BPAFLP), 4-phenyl-3'-(9-phenylfluoren-9-yl) Riphenylamine (abbreviation: mBPAFLP), 4-phenyl-4'-[4-(9-phenyl [Fluorene-9-yl)phenyl]triphenylamine (abbreviation: BPAFLBi), 4 -phenyl-4'-(9-phenyl-9H-carbazole-3-yl)triphenylamine (Abbreviation: PCBA1BP), 4,4'-diphenyl-4''-(9-phenyl-9H- Carbazole-3-yl)triphenylamine (abbreviation: PCBBi1BP), 4-(1- Naphthyl)-4'-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBANB), 4,4'-di(1-naphthyl)-4''-(9-phenyl- 9H-carbazole-3-yl)triphenylamine (abbreviation: PCBNBB), N-Fe Nyl-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]spiro 9,9'-Bifluoren-2-amine (abbreviation: PCBASF), N-(1,1'-Bifluoren-2-amine), Nyl-4-yl)-9,9-dimethyl-N-[4-(9-phenyl-9H-carbazole] Examples include -3-yl)phenyl]-9H-fluoren-2-amine (abbreviation: PCBBiF). It is possible to do so.

[0100] Furthermore, for organic compounds that possess hole-transporting properties, their hole mobility is the square of the electric field strength [V / cm]. If the root is 600, then 1 × 10 -3 cm 2 It is preferable that it is less than or equal to / Vs.

[0101] The ratio of acceptor and hole transporting organic compounds in composite materials is 1:0.0 A ratio of 1 to 1:0.15 (by weight) is preferred. More preferably, 1:0.0 The ratio is 1 to 1:0.1 (by weight).

[0102] The hole injection layer 111 uses the composite material described above, and the hole transporting organic compound is used When using organic compounds with a HOMO level between -5.7eV and -5.4eV, the electron transport As the second framework of the electron transport material in the transport layer 114, condensed aromatic carbon with 2 to 4 rings is used. A hydrogen ring can be used.

[0103] Furthermore, in this case, the electron mobility of the electron transport layer 114 is equal to the square root of the electric field strength [V / cm]. If it is 00, then 1 × 10 -7 cm 2 / Vs or more 5×10 -5 cm 2 / Vs is less than or equal to This is preferable.

[0104] Furthermore, in this case, the electron transport layer 114 contains a metal, a metal salt, a metal oxide, or an organometallic salt. Preferably, the metal, metal salt, metal oxide, or organometallic salt is an alkali metal. It is preferable that the metal complex contains an alkaline earth metal. Preferably, the ligand has nitrogen and oxygen, and the ligand is 8-hydroxyquino It is more preferable that the complex contains a linat structure. Among such metal complexes, monovalent metal ions are preferred. A complex of the following is preferred, specifically, for example, 8-hydroxyquinolinatolithium (abbreviated as L It is preferable that it contains iq, 8-hydroxyquinolinato-sodium (abbreviated as Naq), etc. Lithium complexes are particularly preferred, and Liq is more preferred. If it contains a nolinate structure, its methyl-substituted derivatives (e.g., 2-methyl-substituted derivatives or 5-methyl-substituted derivatives) You can also use words like "body" (or similar).

[0105] As described above, the electron transport layer 114 contains a metal, a metal salt, a metal oxide, or an organometallic salt, and When using multiple transport materials together, the metal, metal salt, metal oxide, or organometallic salt will transport the holes. To assist the receiving function, a condensation of 2 to 4 rings is formed as a second framework for the electron transport material. Aromatic hydrocarbon rings can be suitably used. Suitable configuration as a condensed aromatic hydrocarbon ring. As mentioned above, the condensed aromatic hydrocarbon rings of two to four rings include, for example, naphthalene ring, fluorene ring, anthracene ring, phenanthrene ring, tetracene ring, Examples include lysene rings, triphenylene rings, and pyrene rings. Furthermore, the second skeleton and A condensed aromatic ring with 3 to 4 rings is preferred, and more preferably, an anthracene ring. ru.

[0106] Furthermore, the above-mentioned metal, metal salt, metal oxide, or organometallic salt in the electron transport layer 114 is It is preferable that a concentration difference (including cases where the concentration is 0) exists in the thickness direction. This makes it possible to create light-emitting devices with even better lifespan and reliability.

[0107] Furthermore, the electron transport material used in the electron transport layer 114 has a HOMO level of -6.0 eV. It is preferable that the above conditions are met.

[0108] In a light-emitting device having such a configuration, a drive test under conditions of constant current density is performed. In the resulting luminance degradation curve, if it shows a shape with a maximum value, that is, time In some cases, the shape may have areas where the brightness increases over time. The light-emitting device shown exhibits a rapid degradation during the initial stages of operation, known as initial degradation, which is associated with the increase in brightness. This makes it possible to offset the initial degradation, resulting in low initial degradation and a very good operating life. This makes it possible to create a light-emitting device. Such a light-emitting device is called a Recombi Nation-Site Tailoring Injection Element (ReSTI element) They shall be referred to as children.

[0109] This means that the hole injection layer having the above-described configuration transports hole transport material to deep HOMO levels. Because of this, the induced holes are easily injected into the hole transport layer and the light-emitting layer. In the initial stages of the drive, a small number of holes pass through the light-emitting layer and reach the electron transport layer. It is easy to create a state where the goal is reached.

[0110] Here, electron transport materials and alkali metals or alkaline earth metals in elemental form, compound, or complex form. In a light-emitting device having an electron transport layer, when the light-emitting device is continuously lit, electron transport An improvement in the electron injection and transport properties of the transport layer is observed. On the other hand, as mentioned above, the hole injection layer Because hole induction is moderately suppressed, a large number of holes are supplied to the electron transport layer. It is not possible. As a result, the number of holes that can reach the electron transport layer decreases over time, and the holes remain in the light-emitting layer. This increases the probability of recombination with electrons. In other words, during continuous illumination, recombination occurs more frequently within the light-emitting layer. A shift in career balance occurs, making it more likely for this to happen. This shift can lead to a decline in quality. A light-emitting device with suppressed initial degradation, in which the line has a portion where the brightness increases over time. You can obtain S.

[0111] A light-emitting device according to one aspect of the present invention having the above configuration is a light-emitting device with a very good lifespan. It can be used as a vice, especially in the region where degradation is extremely small, up to around LT95. It is possible to significantly extend the lifespan. Furthermore, as an electron transport material, it can transport electrons. A first skeleton having the ability to accept holes, a second skeleton having the function of accepting holes, and a monoring and π electron-free Luminescence according to one aspect of the present invention using a compound having a third skeleton which is a foot-shaped heteroaromatic ring. The device is a light-emitting device with very little long-term degradation, and furthermore, it is a light-emitting device with a good lifespan. It can be used as a chair.

[0112] Furthermore, the ability to suppress initial degradation is one of the major weaknesses of OLED devices. The issue of seizing, which is still a subject of discussion, and the pre-shipment aging process taken to reduce it. This also significantly reduces the time spent waiting.

[0113] The hole transport layer 112 may be a single layer (Figure 1(A)), but the first hole transport layer 112- It is preferable to have 1 and a second hole transport layer 112-2 (Figure 1(B)). It may have multiple hole transport layers.

[0114] The hole transport layer 112 can be formed using a hole transport material. The hole transport material used in 2 is a hole transport material that can be used as the host material as described above. Alternatively, organic compounds with hole-transporting properties that can be used as composite materials can be employed. Cut.

[0115] When the hole transport layer 112 is formed as multiple layers, the hole transport layers constituting adjacent hole transport layers The HOMO level of the transport material is deeper for the material used in the hole transport layer on the light-emitting layer 113 side. Preferably, the difference is within 0.2 eV.

[0116] Furthermore, if the hole injection layer 111 is formed of a composite material, the positive in contact with the hole injection layer 111 The HOMO level of the hole transport material used in the pore transport layer 112 is the same as the hole transport material used in the composite material. It is preferable that the depth is greater than that of the transportable organic compound, and that the difference is within 0.2 eV. It's nice.

[0117] Because the HOMO levels have the above relationship, holes are smoothly injected into each layer. This prevents an increase in the driving voltage and an insufficient number of holes in the light-emitting layer.

[0118] Furthermore, the hole transport material used in the hole transport layer 112 is a skeleton that has the function of transporting holes. It is preferable to have these. The skeleton having the function of transporting these holes is an organic compound Carbazole skeleton, dibenzofuran skeleton, and dibenzothin Ofen skeletons and anthracene skeletons are preferred, and dibenzofuran skeletons are particularly preferred. Furthermore, between adjacent layers in the hole injection layer 111 and the multiple hole transport layers 112 It is preferable that these skeletons are common because it allows for smoother hole injection. Between adjacent layers in the injection layer 111 and the multiple hole transport layers 112, the same hole Using transport materials is preferable for the same reason.

[0119] When stacking multiple hole transport layers, the first hole transport layer 112-1 is connected to the second hole transport layer 11 It is assumed to be located closer to the anode 101 than 2-2. The second hole transport layer 112-2 is In some cases, it may also simultaneously perform the functions of the electronic block layer.

[0120] A light-emitting device according to one aspect of the present invention having the above configuration provides a light-emitting device with a very good lifespan. It can be used as a vise.

[0121] (Embodiment 2) Next, we will describe the detailed structure and material examples of the light-emitting device described above. It has an EL layer 103 consisting of multiple layers between a pair of electrodes, an anode 101 and a cathode 102. The EL layer 103 has at least the light-emitting layer 113 and electron transport layer 114 from the anode 101 side. The following will be explained using the included configuration as an example. The layers included in the EL layer 103 are the hole injection layer and the hole injection layer. Various layers such as electron injection layers, carrier blocking layers, exciton blocking layers, and charge generation layers. The structure can be applied.

[0122] Anode 101 is a metal, alloy, or conductive compound with a large work function (specifically, 4.0 eV or more). It is preferable to form them using materials and mixtures thereof. Specifically, for example, Indium tin oxide (ITO), silicon, etc. Or silicon dioxide-containing indium oxide-tin oxide, indium oxide-zinc oxide, oxide Examples include indium oxide (IWZO) containing tungsten and zinc oxide. These conductive metal oxide films are usually deposited by sputtering, but the sol-gel method is also used. Any method can be used to manufacture it. An example of a manufacturing method is indium oxide-zinc oxide. Sputtering is performed using a target to which 1-20 wt% zinc oxide has been added to indium oxide. There are methods such as the ring method for formation. Also, it contains tungsten oxide and zinc oxide. Indium oxide (IWZO) is found to be 0.5 to 5 times more tungsten oxide than indium oxide. Using a target containing wt% and 0.1-1 wt% zinc oxide, the sputtering method is used. It can also be formed from gold (Au), platinum (Pt), nickel (Ni), and tungsten. Gusten (W), chromium (Cr), molybdenum (Mo), iron (Fe), cobalt (Co) copper (Cu), palladium (Pd), or nitrides of metallic materials (e.g., titanium nitride), etc. These include graphene, which can also be used. Note that here the work function is large and explicit While representative materials for forming the electrode have been listed, in one aspect of the present invention, the hole injection layer 1 11. An organic compound having hole transport properties and a substance exhibiting electron-accepting properties for said organic compound. Because a composite material containing these elements is used, the electrode material can be selected regardless of the work function.

[0123] Regarding the laminated structure of the EL layer 103, in this embodiment, as shown in Figure 1(B), holes Injection layer 111, hole transport layer 112 (first hole transport layer 112-1, second hole transport layer 11 2-2) Light-emitting layer 113, electron transport layer 114 (first electron transport layer 114-1, second electron A configuration having an electron injection layer 115 in addition to the transport layer 114-2) will be described. The materials used are described below in detail.

[0124] Hole injection layer 111, hole transport layer 112 (first hole transport layer 112-1, second hole transport layer 112-2), light-emitting layer 113 and electron transport layer 114 (first electron transport layer 114-1, the Regarding electron transport layer 2 (114-2), it was described in detail in Embodiment 1, so this is a repetition. The details are omitted. Please refer to the description of Embodiment 1.

[0125] Between the electron transport layer 114 and the cathode 102, an electron injection layer 115 is provided, which is lithium fluoride. Alkaline compounds such as LiF, cesium fluoride (CsF), and calcium fluoride (CaF2) A layer containing a metal or alkaline earth metal or a compound thereof may be provided. Electron injection layer 1 15 is a layer made of an electron-transporting material containing alkali metals or alkaline earth metals or Products containing those compounds or electrides may also be used. Electrides and For example, a substance obtained by adding a high concentration of electrons to a mixed oxide of calcium and aluminum. These are some examples.

[0126] Furthermore, instead of the electron injection layer 115, a charge generation layer is provided between the electron transport layer 114 and the cathode 102. It may be provided. The charge generating layer generates a positive charge on the layer in contact with the cathode side of the layer by applying a potential. A pore is a layer that can inject electrons into the layer in contact with the anode. The charge generation layer is , and includes at least a P-type layer. The P-type layer can constitute the hole injection layer 111 described above. It is preferable to form it using the composite material listed as the material that can be used. Furthermore, the P-type layer is made of a composite material The material consists of a film containing the acceptor material described above and a film containing the hole transport material. It may be constructed in layers. By applying a potential to the P-type layer, electrons are transported to the electron transport layer 114. Then, holes are injected into cathode 102, and the light-emitting device operates.

[0127] In addition to the P-type layer, the charge generation layer consists of one or the other of the electron relay layer and the electron injection buffer layer. It is preferable that both are provided.

[0128] The electron relay layer includes at least an electron-transporting material, and consists of an electron injection buffer layer and a P-type layer. It has the function of preventing interaction with and smoothly transferring electrons. Included in the electron relay layer. The LUMO level of an electron-transporting material is the same as the LUMO level of an electron-accepting material in the P-type layer. The position and the LUMO level of the material contained in the layer in contact with the charge generation layer in the electron transport layer 114. It is preferable that it be between the following. In an electron-transporting material used in an electron relay layer The specific energy level of the LUMO level is -5.0 eV or higher, preferably -5.0 eV or lower. The upper limit should be -3.0 eV or less. Furthermore, the electron relay layer should have electron transport properties. The materials are phthalocyanine-based materials or metal complexes having a metal-oxygen bond and aromatic ligands. Using the body is preferable.

[0129] The electron injection buffer layer contains alkali metals, alkaline earth metals, rare earth metals, and these Compounds (alkali metal compounds (oxides such as lithium oxide, halides, lithium carbonate) (including carbonates such as cesium carbonate), alkaline earth metal compounds (oxides, halides, (including carbonates), or compounds of rare earth metals (including oxides, halides, and carbonates) It is possible to use materials with high electron injection capabilities, such as those mentioned above.

[0130] Furthermore, the electron injection buffer layer is formed by including an electron-transporting material and an electron-donating material. In such cases, alkali metals, alkaline earth metals, rare earth metals, and these compounds (alkali metal compounds (oxides such as lithium oxide, halides, (including carbonates such as lithium carbonate and cesium carbonate), alkaline earth metal compounds (oxides, ha (including chlorosides and carbonates), or compounds of rare earth metals (oxides, halides, carbonates) In addition to salts, it also contains tetratianaphthalene (abbreviation: TTN), nickelosene, and decamethyl Organic compounds such as nickelosene can also be used. Furthermore, as a substance possessing electron transport properties... Therefore, it is formed using the same material as the material that constitutes the electron transport layer 114 described earlier. It is possible.

[0131] As the material that forms cathode 102, gold with a small work function (specifically, 3.8 eV or less) is used. Compounds, alloys, electrically conductive compounds, and mixtures thereof can be used. Specific examples of cathode materials include alkali metals such as lithium (Li) and cesium (Cs). , and elements such as magnesium (Mg), calcium (Ca), and strontium (Sr). Elements belonging to Group 1 or Group 2 of the periodic table, and alloys containing them (MgAg, AlL i) Rare earth metals such as europium (Eu) and ytterbium (Yb), and those containing these Examples include alloys, etc. However, between the cathode 102 and the electron transport layer, an electron injection layer is provided. By providing this, regardless of the magnitude of the work function, Al, Ag, ITO, silicon, or acid Various conductive materials such as indium oxide-tin oxide containing silicon dioxide are used as cathode 102. It is possible to be there. These conductive materials are produced using dry methods such as vacuum deposition and sputtering, as well as inkjet methods. It is possible to deposit films using methods such as spin coating. Furthermore, wet deposition can be performed using the sol-gel method. It may be formed by a mold or by a wet process using a paste of a metallic material.

[0132] Furthermore, various methods can be used to form the EL layer 103, regardless of whether they are dry or wet methods. This can be done using methods such as vacuum deposition, gravure printing, offset printing, and screen printing. You may use methods such as printing, inkjet printing, or spin coating.

[0133] Furthermore, each electrode or layer described above may be formed using different film deposition methods.

[0134] The configuration of the layer provided between the anode 101 and the cathode 102 is not limited to the above. No. However, the proximity of the light-emitting region to the metal used in the electrodes and carrier injection layer can lead to... To suppress the resulting quenching, holes are placed in a location away from the anode 101 and cathode 102. A configuration in which a light-emitting region is provided where electrons and other elements recombine is preferable.

[0135] Furthermore, the hole transport layer and electron transport layer in contact with the light-emitting layer 113, and especially the recombination in the light-emitting layer 113, The carrier transport layer near the region suppresses energy transfer from excitons generated in the light-emitting layer. Therefore, the band gap is the light-emitting material that makes up the light-emitting layer or the light contained in the light-emitting layer. It is preferable to use a material with a band gap larger than that of the material itself.

[0136] Next, we have a light-emitting device (multilayer element, tandem element) with a configuration in which multiple light-emitting units are stacked. The form of the (also called the child) will be explained with reference to Figure 1(C). This light-emitting device is positive This is a light-emitting device having multiple light-emitting units between the electrode and the cathode. The EL layer 103 has a configuration almost identical to that shown in Figure 1(A) or (B). The light-emitting device shown in Figure 1(C) is a light-emitting device having multiple light-emitting units, The light-emitting device shown in Figures 1(A) and 1(B) is a light-emitting device having one light-emitting unit. It can be said that it is a S.

[0137] In Figure 1(C), a first light-emitting unit 511 and a cathode 502 are located between the anode 501 and the cathode 502. A second light-emitting unit 512 is stacked with the first light-emitting unit 511 and the second light-emitting unit A charge generation layer 513 is provided between the knit 512 and the cathode 502. These correspond to the anode 101 and cathode 102 in Figure 1(A), respectively, and are described in the explanation of Figure 1(A). The same thing can be applied as is. Also, the first light-emitting unit 511 and the second light-emitting unit The optical unit 512 may have the same configuration or a different configuration.

[0138] When a voltage is applied to the anode 501 and cathode 502, the charge generation layer 513 generates a light from one of the light-emitting units. It has the function of injecting electrons into one unit and holes into the other light-emitting unit. That is, Figure In 1(C), when a voltage is applied such that the potential of the anode is higher than the potential of the cathode... In addition, the charge generation layer 513 injects electrons into the first light-emitting unit 511 and the second light-emitting unit Any method that injects a hole into T512 will suffice.

[0139] The charge generation layer 513 is preferably formed with the same configuration as the charge generation layer described above. Composite materials of compounds and metal oxides have excellent carrier implantation and carrier transport properties, Low voltage and low current operation can be achieved. Note that the anode side of the light-emitting unit is electrically charged. When in contact with the charge generation layer 513, the charge generation layer 513 acts as the hole injection layer of the light-emitting unit. Since it can also handle the splitting, the light-emitting unit does not need to have a hole injection layer.

[0140] Furthermore, if an electron injection buffer layer is provided in the charge generation layer 513, the electron injection buffer layer In order to play the role of an electron injection layer in the anode-side light-emitting unit, the anode-side light-emitting unit has It is not always necessary to form an electron injection layer.

[0141] Figure 1(C) illustrates a light-emitting device having two light-emitting units, but there are also devices with three or more units. The same method can be applied to light-emitting devices that stack the above light-emitting units. As in the light-emitting device according to this embodiment, multiple light-emitting units are charged between a pair of electrodes. By separating and arranging the elements with the generation layer 513, high-brightness light emission is possible while maintaining a low current density. This enables the realization of even longer-lasting elements. Furthermore, it allows for low-voltage operation and low power consumption of light-emitting elements. The device can be realized.

[0142] Furthermore, by making the light-emitting color of each light-emitting unit different, the entire light-emitting device... This allows you to obtain light emission of the desired color. For example, a light emission device having two light emission units In the vise, the first light-emitting unit emits red and green light, and the second light-emitting unit emits blue light. By obtaining color, it is also possible to obtain a light-emitting device that emits white light as a whole. Yes, there is. Furthermore, an example of a light-emitting device configuration in which three or more light-emitting units are stacked is: The first light-emitting unit has a first blue light-emitting layer, and the second light-emitting unit has a yellow or yellowish-green light-emitting layer. The third light-emitting unit has a colored light-emitting layer and a red light-emitting layer, and the third light-emitting unit has a second blue light-emitting layer. This can be a tandem type device. This tandem type device is the above-mentioned light-emitting device Similar to the chair, it can emit white light.

[0143] Furthermore, the EL layer 103, the first light-emitting unit 511, the second light-emitting unit 512 and Each layer, such as the charge generation layer, and the electrodes are, for example, deposited by methods such as vapor deposition (including vacuum deposition) and droplet ejection ( It can be formed using methods such as inkjet printing, coating, and gravure printing. They can be used. Also, they include low molecular weight materials, medium molecular weight materials (including oligomers and dendrimers), and Alternatively, it may contain polymer materials.

[0144] (Embodiment 3) In this embodiment, light emission using the light-emitting device described in Embodiment 1 and Embodiment 2 is demonstrated. Let me explain the device.

[0145] In this embodiment, the light-emitting device described in Embodiment 1 and Embodiment 2 is used for fabrication. The light-emitting device described will be explained using Figure 2. Figure 2(A) shows the light-emitting device. The top view, Figure 2(B), is a cross-sectional view of Figure 2(A) cut along lines AB and CD. This light emission The device controls the light emission of the light-emitting device, and the drive circuit section (source) is shown by the dotted line. It includes a line drive circuit (601), a pixel section (602), and a drive circuit section (gate line drive circuit) (603). Furthermore, 604 is the sealing substrate, and 605 is the sealing material, and the inside surrounded by the sealing material 605 This is space 607.

[0146] The routing wire 608 is input to the source line drive circuit 601 and the gate line drive circuit 603. FPC (Flexible Printed Circuit) is a wiring system for transmitting signals and serves as an external input terminal. (Input circuit) 609 receives video signals, clock signals, start signals, reset signals, etc. Receive. Note that only the FPC is shown in the diagram here, but this FPC has a print distribution A wire substrate (PWB) may be attached. The light-emitting device described herein includes a light-emitting device This includes not only the main unit but also the state in which the FPC or PWB is attached to it. ru.

[0147] Next, the cross-sectional structure will be explained using Figure 2(B). The drive circuit section is located on the element substrate 610. And a pixel section is formed, but here, the source line drive circuit 601 which is the drive circuit section and One pixel in the pixel section 602 is shown.

[0148] The element substrate 610 is a substrate made of glass, quartz, organic resin, metal, alloy, semiconductor, etc. FRP (Fiber Reinforced Plastics), PVF (Polyvinyl Fiber) It is made using a plastic substrate made of fluoride, polyester, or acrylic. That's all you need to do.

[0149] The structure of transistors used in pixels and driving circuits is not particularly limited. For example, inverse staggered It can be a type of transistor or a staggered transistor. Also, top Either a gate-type transistor or a bottom-gate transistor is acceptable. The semiconductor material is not particularly limited, and examples include silicon, germanium, silicon carbide, nitride Gallium can be used, or an In-Ga-Zn metal oxide can be used. An oxide semiconductor containing at least one of the elements, such as zinc, gallium, and zinc, may also be used.

[0150] The crystallinity of semiconductor materials used in transistors is not particularly limited; amorphous semiconductors, Crystalline semiconductors (microcrystalline semiconductors, polycrystalline semiconductors, single-crystal semiconductors, or semiconductors with a crystalline region in part) Any semiconductor having the properties of [the semiconductor material] may be used. If a semiconductor having crystalline properties is used, transients may occur. This is preferable because it suppresses the deterioration of the stanic characteristics.

[0151] Here, in addition to the transistors provided in the pixels and driving circuits mentioned above, the touch sensors and the like described later are also included. It is preferable to use oxide semiconductors for semiconductor devices such as transistors. It is particularly preferable to use oxide semiconductors with a wider band gap than silicon. By using an oxide semiconductor with a wider band gap than Ricon, the off state of the transistor can be controlled. The current in this state can be reduced.

[0152] The above oxide semiconductor preferably contains at least indium (In) or zinc (Zn). It is also In-M-Zn oxides (where M is Al, Ti, Ga, Ge, Y, Zr, Sn, It is an oxide semiconductor containing an oxide (such as a metal like La, Ce, or Hf). It is preferable.

[0153] Herein, an oxide semiconductor that can be used in one aspect of the present invention will be described below. .

[0154] Oxide semiconductors are divided into single-crystal oxide semiconductors and other non-single-crystal oxide semiconductors. As a non-single-crystal oxide semiconductor, for example, CAAC-OS (c-axis ali gned crystalline oxide semiconductor), polycrystalline crystalline oxide semiconductor, nc-OS (nano crystalline oxide sem iconductor), pseudo-amorphous oxide semiconductor (a-like OS: amorph (Amorphous-like oxide semiconductor), and amorphous oxide semiconductor It contains conductors, etc.

[0155] CAAC-OS has c-axis orientation and multiple nanocrystals are linked in the ab-plane direction. Furthermore, it has a distorted crystal structure. Note that distortion refers to the region where multiple nanocrystals are connected. Within the region, between a region with aligned lattice arrangements and another region with aligned lattice arrangements, This refers to the part where the direction has changed.

[0156] Nanocrystals are based on a hexagonal structure, but they are not necessarily regular hexagons; they can also be non-regular hexagonal. Yes, it exists. Furthermore, the distortion may have lattice arrangements such as pentagons and heptagons. Furthermore, in CAAC-OS, even near strain, clear grain boundaries (grain bounds) are present. It is difficult to confirm (also called Dally) the crystal grains. In other words, due to the distortion of the lattice arrangement, It can be seen that the formation of the boundary is suppressed. This is because CAAC-OS is in the ab-plane direction. The oxygen atoms are not densely arranged, and the substitution of metal elements reduces the bond distance between atoms. This is because distortion can be tolerated through changes and other processes.

[0157] Furthermore, CAAC-OS consists of a layer containing indium and oxygen (hereinafter referred to as the In layer), and elements A layered crystalline structure in which layers containing M, zinc, and oxygen (hereinafter referred to as (M,Zn) layers) are stacked. It tends to have a layered structure (also called a structure). Furthermore, indium and element M are substituted for each other. It is possible, and if element M in the (M,Zn) layer is replaced with indium, then (In,M,Zn) It can also be represented as a layer. Furthermore, if the indium in the In layer is substituted with element M, then (In,M It can also be represented as a layer.

[0158] CAAC-OS is a highly crystalline oxide semiconductor. On the other hand, CAAC-OS has a clear bond. Because it is difficult to confirm grain boundaries, a decrease in electron mobility caused by grain boundaries is less likely to occur. It can be said that... Furthermore, the crystallinity of oxide semiconductors decreases due to the inclusion of impurities and the generation of defects. Because this can occur, CAAC-OS may contain impurities or defects (oxygen deficiencies (V O :oxygen It can also be described as an oxide semiconductor with low vacancy (also called CAA). Therefore, CAA Oxide semiconductors containing C-OS exhibit stable physical properties. Therefore, CAAC-OS The oxide semiconductors it possesses are highly heat-resistant and reliable.

[0159] nc-OS is used in minute regions (for example, regions between 1 nm and 10 nm, especially between 1 nm and 3 nm). It has periodicity in the atomic arrangement in the region of less than nm. Furthermore, nc-OS has different nanometers. No regularity in crystal orientation is observed between crystals. Therefore, no orientation is observed throughout the entire film. Therefore, depending on the analysis method, nc-OS can be classified as a-like OS or amorphous oxide semiconductor. It can sometimes be difficult to distinguish between them.

[0160] Furthermore, indium is a type of oxide semiconductor containing indium, gallium, and zinc. Um-gallium-zinc oxide (hereinafter referred to as IGZO) is stable when formed into the nanocrystals described above. It may take on a structure. In particular, IGZO tends to have difficulty growing crystals in the atmosphere. Smaller crystals (for example) are preferable to larger crystals (here, crystals of a few millimeters or a few centimeters). In some cases, using the aforementioned nanocrystal structure may result in greater structural stability.

[0161] a-like OS is an oxide semiconductor having a structure between nc-OS and amorphous oxide semiconductors. It is a conductor. a-like OS has porous or low-density regions. That is, a-li ke OS has lower crystallinity compared to nc-OS and CAAC-OS.

[0162] Oxide semiconductors can take on diverse structures, each possessing different properties. One embodiment of the present invention Oxide semiconductors include amorphous oxide semiconductors, polycrystalline oxide semiconductors, a-like OS, and nc -OS and CAAC-OS may have two or more types.

[0163] In addition to the oxide semiconductors mentioned above, CAC (Cloud-Aligned Comp You may also use osite)-OS.

[0164] CAC-OS refers to a material that possesses both conductive and insulating properties in some parts. Furthermore, the material as a whole possesses semiconductor functionality. Note that CAC-OS is used in transistors. When used in the active layer, the conductive function is to allow electrons (or holes) that act as carriers to flow. The insulating function is the function of preventing the flow of electrons, which act as carriers. By having the insulating function and the switching function work complementaryly, the switching function (O The function to turn on / off can be added to CAC-OS. By separating each function, it is possible to maximize the performance of both.

[0165] Furthermore, CAC-OS has conductive regions and insulating regions. The conductive region is the conductive region described above. It has electrical properties, and the insulating region has the aforementioned insulating properties. Furthermore, in the material In some cases, the conductive region and the insulating region are separated at the nanoparticle level. The electrically conductive region and the insulating region may be unevenly distributed within the material. In some cases, the surrounding area may appear blurred and connected in a cloud-like manner.

[0166] Furthermore, in CAC-OS, the conductive region and the insulating region are each 0.5 nm or greater. In the case where particles are dispersed in the material with a size of 10 nm or less, preferably 0.5 nm to 3 nm. There is a match.

[0167] Furthermore, CAC-OS is composed of components with different band gaps. For example, CAC-OS consists of a component with a wide gap due to the insulating region and a component that occurs in the conductive region. It is composed of a component having a narrow gap due to and . In this configuration, the carrier When flowing, the carrier mainly flows in the component with a narrow gap. Components with gaps act complementaryly with components with wide gaps, and narrow gaps In conjunction with the component having a gap, the carrier also flows to the component having a wide gap. When the above CAC-OS is used in the channel formation region of a transistor, the transistor In the ON state, a high current driving force, i.e., a large ON current and high field effect mobility are obtained. It is possible.

[0168] In other words, CAC-OS is a matrix composite. , or metal matrix composite and It can also be referred to as such.

[0169] By using the aforementioned oxide semiconductor material as the semiconductor layer, fluctuations in electrical properties are suppressed, and reliability This enables the creation of highly reliable transistors.

[0170] Furthermore, due to its low off-current, the transistor having the aforementioned semiconductor layer can be used to... This makes it possible to retain the charge stored in the capacity over a long period of time. By applying a generator to each pixel, the gradation of the image displayed in each display area is maintained while driving It also becomes possible to shut down the circuit. As a result, it is possible to realize electronic devices with extremely reduced power consumption. It can be expressed.

[0171] It is preferable to provide an undercoat to stabilize the characteristics of the transistor. The undercoat may be: Inorganic silicon oxide films, silicon nitride films, silicon oxide-nitride films, silicon nitride-oxide films, etc. It can be fabricated using an insulating film, either as a single layer or in a multilayer configuration. The underlayer is fabricated by sputtering. CVD (Chemical Vapor Deposition) method (Plasma CVD method) , thermal CVD method, MOCVD (Metal Organic CVD) method, ALD ( Formed using methods such as Atomic Layer Deposition, coating, and printing. Yes, it is possible. However, a base coat does not need to be applied unless necessary.

[0172] Note that FET623 is one of the transistors formed in the drive circuit section 601. Furthermore, the drive circuit is formed using various CMOS, PMOS, or NMOS circuits. This is sufficient. Furthermore, in this embodiment, a driver-integrated type in which the drive circuit is formed on the substrate is shown. However, this is not always necessary, and the drive circuit can be formed externally rather than on the circuit board. .

[0173] Furthermore, the pixel section 602 includes a switching FET 611 and a current control FET 612 and its drive It is formed by multiple pixels, including an anode 613 electrically connected to the rain, The pixel section may also be a combination of three or more FETs and a capacitive element.

[0174] Furthermore, an insulator 614 is formed covering the end of the anode 613. Here, a positive type sensor It can be formed by using light-sensitive acrylic.

[0175] Furthermore, in order to ensure good coverage of the EL layer and other layers formed later, the upper end of the insulator 614 is Alternatively, a curved surface with curvature is formed at the lower end. For example, the material of the insulator 614 and When a positive-type photosensitive acrylic is used, the radius of curvature (0.) is only at the upper end of the insulator 614. It is preferable to have a curved surface having a thickness of 2 μm to 3 μm. Also, as the insulator 614, Either a negative-type or positive-type photosensitive resin can be used.

[0176] An EL layer 616 and a cathode 617 are formed on the anode 613, respectively. Therefore, it is desirable to use a material with a large work function for the anode 613. For example, an ITO film, or an indium tin oxide film containing silicon, 2-20 wt% oxidation Indium oxide film containing zinc, titanium nitride film, chromium film, tungsten film, Zn film, Pt In addition to single-layer films such as membranes, lamination of titanium nitride films and films mainly composed of aluminum, titanium nitride A three-layer structure consisting of a film, a film mainly composed of aluminum, and a titanium nitride film can be used. Furthermore, a laminated structure results in low resistance as wiring and good ohmic contact. Furthermore, it can be used as an anode.

[0177] Furthermore, the EL layer 616 was coated using a vapor deposition method with a vapor deposition mask, an inkjet method, and a spin coating method. It is formed by various methods such as the above. The EL layer 616 is formed by Embodiment 1 and Embodiment 2 It includes the configuration described above. Furthermore, other materials constituting the EL layer 616 include: It may be a low molecular weight compound or a high molecular weight compound (including oligomers and dendrimers). .

[0178] Furthermore, the material used for the cathode 617 formed on the EL layer 616 has a small work function. Materials (Al, Mg, Li, Ca, or alloys and compounds thereof (MgAg, MgIn, It is preferable to use AlLi, etc. Furthermore, the light generated in the EL layer 616 is directed to the cathode 617 When allowing light to pass through, the cathode 617 consists of a thin metal film and a transparent conductive film (I TO, indium oxide containing 2-20 wt% zinc oxide, and indium tin containing silicon. It is preferable to use lamination with oxides (such as zinc oxide (ZnO)).

[0179] The anode 613, EL layer 616, and cathode 617 form the light-emitting device. The light-emitting device is the light-emitting device described in Embodiment 1 and Embodiment 2. Oh, the pixel section is made up of multiple light-emitting devices, but the light emission in this embodiment The apparatus includes the light-emitting device described in Embodiment 1 and Embodiment 2, and other components. Both of the light-emitting devices may be included.

[0180] Furthermore, by bonding the sealing substrate 604 to the element substrate 610 with the sealing material 605, A light-emitting device is placed in the space 607 surrounded by the sub-substrate 610, the sealing substrate 604, and the sealing material 605. The structure is equipped with chair 618. Furthermore, the space 607 is filled with filler material. In addition to cases where inert gases (such as nitrogen or argon) are used for filling, there are also cases where sealing materials are used for filling. There are also cases where a recess is formed in the sealing substrate and a desiccant is placed there to prevent deterioration due to moisture. This configuration is preferable because it can suppress oxidation.

[0181] Furthermore, it is preferable to use epoxy resin or glass frit for the sealing material 605. These materials should ideally be as impermeable to moisture and oxygen as possible. In addition to glass substrates and quartz substrates, other materials can be used for the encapsulating substrate 604, such as FRP (Fiber Reinforced Plastic). reinforced plastics, PVF (polyvinyl fluoride), polyester A plastic substrate made of tel or acrylic can be used.

[0182] Although not shown in Figure 2(B), a protective film may be provided on the cathode. The protective film is an organic resin film. It can be formed with an inorganic insulating film. Also, the exposed portion of the sealing material 605 can be covered with A protective film may be formed. The protective film may also be on the surface and sides of the pair of substrates, a sealing layer, and an insulating layer. It can be installed to cover exposed surfaces such as the margin layer.

[0183] The protective film can be made of a material that is impermeable to impurities such as water. This effectively suppresses the diffusion of impurities such as these from the outside to the inside.

[0184] Materials that make up the protective film include oxides, nitrides, fluorides, sulfides, ternary compounds, and metals. Alternatively, polymers can be used, for example, aluminum oxide, hafnium oxide, etc. Phenium silicate, lanthanum oxide, silicon oxide, strontium titanate, tantalum oxide Titanium dioxide, zinc oxide, niobium oxide, zirconium oxide, tin oxide, yttrium oxide cerium oxide, scandium oxide, erbium oxide, vanadium oxide, or indi oxide Materials containing um, etc., as well as aluminum nitride, hafnium nitride, silicon nitride, tantalum nitride, nitrogen Includes titanium dioxide, niobium nitride, molybdenum nitride, zirconium nitride, or gallium nitride, etc. Materials, nitrides containing titanium and aluminum, oxides containing titanium and aluminum oxides containing aluminum and zinc, sulfides containing manganese and zinc, cerium oxides Strontium-containing sulfides, erbium and aluminum-containing oxides, and Materials containing oxides, etc., including lium and zirconium can be used.

[0185] The protective film can be formed using a film deposition method that provides good step coverage. This is preferable. One such method is atomic layer deposition (ALD). There is a deposition method. Protecting materials that can be formed using the ALD method. It is preferable to use it for membranes. By using the ALD method, a dense membrane can be created with cracks and pinholes. A protective film can be formed with reduced defects or with a uniform thickness. Also, This reduces the damage inflicted on the processed material when forming a protective film.

[0186] For example, by forming a protective film using the ALD method, surfaces with complex uneven shapes, or taps can be formed. A uniform and low-defect protective film can be formed on the top, sides, and back surfaces of the panel. .

[0187] As described above, the light-emitting devices described in Embodiments 1 and 2 are used to manufacture the light-emitting devices. A light-emitting device can be obtained.

[0188] The light-emitting device in this embodiment is the same as the light-emitting device described in Embodiment 1 and Embodiment 2. Because it uses a specific material, a light-emitting device with good characteristics can be obtained. Specifically, The light-emitting devices described in Embodiment 1 and Embodiment 2 are long-life light-emitting devices. Therefore, a highly reliable light-emitting device can be made. Also, Embodiment 1 and Embodiment Because the light-emitting device using the light-emitting device described in 2 has good luminous efficiency, it consumes little power. It can be used as an optical device.

[0189] Figures 3(A) and 3(B) show a light-emitting device that emits white light, with a colored layer (color Figure 3(A) shows an example of a light-emitting device that achieves full color by adding filters, etc. It includes a substrate 1001, a base insulating film 1002, a gate insulating film 1003, a gate electrode 1006, 1007, 1008, first interlayer insulating film 1020, second interlayer insulating film 1021, peripheral portion 1 042, pixel section 1040, drive circuit section 1041, anode 1024W, 102 4R, 1024G, 1024B, partition 1025, EL layer 1028, cathode 1 of the light-emitting device 029, the encapsulating substrate 1031, the sealing material 1032, etc. are shown in the diagram.

[0190] Furthermore, Figure 3(A) shows the colored layers (red colored layer 1034R, green colored layer 1034G, blue). The colored layer 1034B is provided on a transparent substrate 1033. Also, the black matrix 1 A 035 layer may be further provided. A transparent substrate 1 having a colored layer and a black matrix. 033 is aligned and fixed to substrate 1001. Note that the colored layer and black matrix Kus 1035 is covered with an overcoat layer 1036. Also, in Figure 3(A) This consists of a light-emitting layer that allows light to escape to the outside without passing through the colored layers, and a layer that allows light to escape to the outside by passing through the colored layers of each color. There is a light-emitting layer, and light that does not pass through the colored layer is white, while light that passes through the colored layer is red, green, and blue. Therefore, images can be represented using four colored pixels.

[0191] Figure 3(B) shows the colored layers (red colored layer 1034R, green colored layer 1034G, blue colored layer Example of forming layer 1034B) between the gate insulating film 1003 and the first interlayer insulating film 1020. This was shown. Thus, the colored layer is provided between the substrate 1001 and the sealing substrate 1031. That's good too.

[0192] Furthermore, in the light-emitting device described above, light is taken to the substrate 1001 side on which the FET is formed. Although a light-emitting device with a bottom-emission structure was used, the light emission was taken from the sealing substrate 1031 side. It may also be a light-emitting device with a top-emission structure. A cross-sectional view of the light-emitting device is shown in Figure 4. In this case, the substrate 1001 is a substrate that does not transmit light. This can be done. Until the connecting electrode that connects the FET and the anode of the light-emitting device is fabricated, the bottle It is formed in the same way as a muemission-type light-emitting device. Then, the third interlayer insulating film 1037 is electrically... It is formed covering pole 1022. This insulating film may also play a planarization role. Third layer The interlayer insulating film 1037 is formed using the same material as the second interlayer insulating film, as well as other known materials. It is possible.

[0193] The anodes 1024W, 1024R, 1024G, and 1024B of the light-emitting devices are referred to here as anodes. However, it is also acceptable to form it as a cathode. Furthermore, a top-emission type emission as shown in Figure 4... In the case of an optical device, it is preferable to use the anode as a reflective electrode. The configuration of the EL layer 1028 is as follows: The configuration is as described in Embodiment 1 and Embodiment 2 as the EL layer 103, and The element structure is designed to produce white light emission.

[0194] In the top emission structure shown in Figure 4, the colored layer (red colored layer 1034R, green colored layer) The sealing is performed using a sealing substrate 1031 having a color layer 1034G and a blue colored layer 1034B. This can be done. The encapsulation substrate 1031 has a black matrix positioned between the pixels. 1035 may be provided. Colored layer (red colored layer 1034R, green colored layer 1034G, The blue colored layer (1034B) and the black matrix are formed by the overcoat layer (1036). It may be covered. The sealing substrate 1031 shall be a light-transmitting substrate. Furthermore, while we have shown an example of full-color display using four colors—red, green, blue, and white—this is not particularly limited. Alternatively, full-color display may be performed using four colors: red, yellow, green, and blue, or three colors: red, green, and blue.

[0195] In top-emission type light-emitting devices, a microcavity structure can be suitably applied. A light-emitting device having a microcavity structure has a reflective electrode as the anode and a semi-transparent / semi-reflective cathode. This is obtained by using a ray electrode. Between the reflective electrode and the semitransmissive / semi-reflective electrode, there is at least It has an EL layer and at least an emissive layer that forms an emissive region.

[0196] The reflective electrode has a visible light reflectance of 40% to 100%, preferably 70% to 100%. It is %, and its resistivity is 1 × 10⁻⁶. -2 Assume the membrane is less than Ωcm in diameter. Also, semipermeable... The semi-reflective electrode has a visible light reflectance of 20% to 80%, preferably 40% to 70%. , and its resistivity is 1 × 10 -2 Assume the membrane is less than Ωcm in diameter.

[0197] The light emitted from the light-emitting layer contained in the EL layer is reflected by the reflective electrode and the semi-transmitting / semi-reflective electrode. It is reflected and resonates.

[0198] The light-emitting device changes the thickness of the transparent conductive film, the aforementioned composite material, the carrier transport material, etc. This allows us to change the optical distance between the reflective electrode and the semitransmissive / semi-reflective electrode. Furthermore, the light of the resonant wavelength is amplified between the reflective electrode and the semitransmissive / semi-reflective electrode, causing resonance. It can attenuate light of wavelengths that are not present.

[0199] Furthermore, the light reflected back by the reflective electrode (the first reflected light) is semi-transmitted from the light-emitting layer. • Because it causes significant interference with the light (first incident light) that directly enters the semi-reflecting electrode, the reflective electrode and The optical distance of the light-emitting layer is (2n-1)λ / 4 (where n is a natural number greater than or equal to 1, and λ is amplified). It is preferable to adjust the wavelength of the emitted light. By adjusting the optical distance, the first By aligning the phase of the reflected light and the first incident light, the light emitted from the light-emitting layer can be further amplified. ru.

[0200] Furthermore, in the above configuration, even if the EL layer has a structure with multiple light-emitting layers, a single light-emitting layer The structure may have layers, for example, in combination with the configuration of the tandem light-emitting device described above. In addition, multiple EL layers are provided in a single light-emitting device with a charge generation layer in between, and each EL This can also be applied to configurations in which one or more light-emitting layers are formed in a layer.

[0201] Having a microcavity structure enhances the emission intensity in the front direction at specific wavelengths. This makes it possible to reduce power consumption. Furthermore, the four sub-colors red, yellow, green, and blue are used. In the case of a light-emitting device that displays images as is, in addition to the brightness enhancement effect of yellow light emission, all sub-pixels By applying a microcavity structure tailored to the wavelength of each color, a light-emitting device with excellent characteristics can be produced. It can be placed there.

[0202] The light-emitting device in this embodiment is the same as the light-emitting device described in Embodiment 1 and Embodiment 2. Because it uses a specific material, a light-emitting device with good characteristics can be obtained. Specifically, The light-emitting devices described in Embodiment 1 and Embodiment 2 are long-life light-emitting devices. Therefore, a highly reliable light-emitting device can be made. Also, Embodiment 1 and Embodiment Because the light-emitting device using the light-emitting device described in 2 has good luminous efficiency, it consumes little power. It can be used as an optical device.

[0203] (Embodiment 4) In this embodiment, the light-emitting devices described in Embodiment 1 and Embodiment 2 are used as an illumination device. Examples of its use will be explained with reference to Figures 5(A) and 5(B). Figure 5(B) shows lighting. Figure 5(A) is a top view of the apparatus, and Figure 5(B) is a cross-sectional view of ef.

[0204] In this embodiment, the lighting device has an anode 4 on a translucent substrate 400 which is a support. 01 is formed. The anode 401 corresponds to the anode 101 in Embodiment 2. Anode When light is extracted from the 401 side, the anode 401 is formed from a translucent material.

[0205] A pad 412 for supplying voltage to the cathode 404 is formed on the substrate 400.

[0206] An EL layer 403 is formed on the anode 401. The EL layer 403 is the same as in Embodiment 1 and the actual Configuration of the EL layer 103 in the second form of application, or light-emitting units 511, 512 and charge generation This corresponds to a configuration including layer 513, etc. For details on these configurations, please refer to the relevant description. I want to be treated that way.

[0207] The cathode 404 is formed by covering the EL layer 403. The cathode 404 is the cathode 1 in Embodiment 2. This corresponds to 02. When light is extracted from the anode 401 side, the cathode 404 is made of a material with high reflectivity. It is formed by the cathode 404 being connected to the pad 412, thereby supplying voltage. It can be done.

[0208] The above describes the light-emitting device having an anode 401, an EL layer 403, and a cathode 404 in this embodiment. The lighting device shown is equipped with the light-emitting device. The light-emitting device is a light-emitting device with high luminous efficiency. Therefore, the lighting device in this embodiment can be a lighting device with low power consumption.

[0209] The substrate 400 on which the light-emitting device having the above configuration is formed and the sealing substrate 407 are sealed The lighting device is completed by fixing and sealing it using materials 405 and 406. Either 405 or 406 is acceptable. Also, the inner sealant 406 (Figure 5 (B) (Not shown) A desiccant can also be mixed in, which allows it to absorb moisture. This leads to improved reliability.

[0210] Furthermore, the pad 412 and a portion of the anode 401 are extended outside the sealing materials 405 and 406. This allows it to be used as an external input terminal. Furthermore, a converter or similar device can be mounted on top of it. An IC chip 420 or the like may be provided.

[0211] As described above, the lighting device described in this embodiment has an EL element as described in Embodiment 1 and Embodiment 2. The light-emitting device described is used, resulting in a highly reliable light-emitting device. Furthermore, This allows for a light-emitting device with low power consumption.

[0212] (Embodiment 5) In this embodiment, the light-emitting device described in Embodiments 1 and 2 is used as a part thereof. Examples of electronic devices to be included will be described. The light-emitting devices described in Embodiment 1 and Embodiment 2 The chair is a reliable light-emitting device with a good lifespan. As a result, this embodiment The electronic device described can be an electronic device having a highly reliable light-emitting part.

[0213] Examples of electronic devices to which the above-mentioned light-emitting device is applied include television equipment (televisions, and (Also called a television receiver), monitors for computers, digital cameras, digital cameras Digital video cameras, digital photo frames, mobile phones (both mobile phones and mobile phone devices) (Examples include) portable game consoles, personal digital assistants, audio playback devices, and large game machines such as pachinko machines. These are some examples. Specific examples of these electronic devices are shown below.

[0214] Figure 6(A) shows an example of a television system. The television system has a housing 710 The display unit 7103 is incorporated into part 1. Also, the housing is connected by the stand 7105. This shows the configuration supporting 7101. The display unit 7103 can display video. The display unit 7103 is capable of displaying the light-emitting devices described in Embodiment 1 and Embodiment 2. It is arranged in a matrix.

[0215] The television equipment can be operated using the control switches on the housing 7101 or a separate remote control. This can be done using the device 7110. The remote control device 7110 has an operation key 7109. This allows you to control the channel and volume, and the video displayed on the display unit 7103 It can be operated. Also, the remote control unit 7110 A display unit 7107 that displays the information output from the unit may also be provided.

[0216] The television system shall consist of a receiver, modem, etc. It can receive television broadcasts, and also communicate via wired or wireless connection through a modem. By connecting to a network, one-way (sender to receiver) or two-way (sender to receiver) communication is possible. It is also possible to communicate information between recipients, or between recipients themselves.

[0217] Figure 6(B1) is a computer, consisting of the main unit 7201, the casing 7202, the display unit 7203, and a key - Includes board 7204, external connection port 7205, pointing device 7206, etc. Furthermore, this computer uses the light-emitting devices described in Embodiment 1 and Embodiment 2. It is manufactured by arranging them in a matrix and using them in the display unit 7203. Figure 6(B1) The computer may take the form shown in Figure 6(B2). The second display unit 7 is used instead of the keyboard 7204 and pointing device 7206. 210 is provided. The second display unit 7210 is a touch panel type, and the second Input is performed by operating the input display shown on the display unit 7210 with a finger or a special pen. This can be done. In addition, the second display unit 7210 can display not only input information but also other images. It is also possible to display an image. Furthermore, the display unit 7203 may also be a touch panel. Because the two screens are connected by a hinge, the screens can get scratched when storing or transporting the device. This also prevents problems such as damage from occurring.

[0218] Figure 6(C) shows an example of a mobile terminal. The mobile phone is incorporated into the housing 7401. In addition to the display unit 7402, there are operation buttons 7403, an external connection port 7404, and a speaker 740 5. It is equipped with a microphone 7406, etc. Note that the mobile phone is the same as in Embodiment 1 and the embodiment. The display unit 7402 is made by arranging the light-emitting devices described in Embodiment 2 in a matrix. It is.

[0219] The mobile terminal shown in Figure 6(C) allows users to input information by touching the display unit 7402 with their fingers or other objects. It can also be configured to allow for making phone calls or composing emails. Operations such as this can be performed by touching the display unit 7402 with a finger or the like.

[0220] The display unit 7402 has three main modes. The first is a display that primarily displays images. The first mode is display mode, the second is input mode which is mainly for inputting information such as characters. The third is display mode. This is a display + input mode, which is a combination of two modes: display mode and input mode.

[0221] For example, when making a phone call or composing an email, the display unit 7402 is used for text input. In this case, the primary text input mode should be used, and you should perform the input operation for the characters displayed on the screen. It is preferable to display a keyboard or number buttons on most of the screen of the display unit 7402. It seems so.

[0222] Furthermore, the mobile device has sensors inside that detect tilt, such as a gyroscope and an accelerometer. By installing the device, the orientation of the mobile terminal (portrait or landscape) is determined, and the screen display of the display unit 7402 is displayed accordingly. The display can be set to switch automatically.

[0223] Furthermore, screen modes can be switched by touching the display unit 7402 or by operating the housing 7401. This is done by operating button 7403. Also, the type of image displayed on display unit 7402 Therefore, it is also possible to switch between them. For example, the image signal displayed on the display unit is a video signal. Switch to display mode if it's data, or to input mode if it's text data.

[0224] Furthermore, in input mode, the signal detected by the optical sensor of the display unit 7402 is detected and displayed If there is no input via touch operation on unit 7402 for a certain period of time, the screen mode will be changed to input mode. You may also control the system to switch from that display mode to a different mode.

[0225] The display unit 7402 can also function as an image sensor. For example, the display unit 74 By touching device 02 with the palm or fingers, the user can be authenticated by capturing images of their palm print, fingerprints, etc. Furthermore, the display unit may have a backlight that emits near-infrared light or a sensing light that emits near-infrared light. Using the appropriate source, it is also possible to image finger veins, palmar veins, and other veins.

[0226] The configuration shown in this embodiment is a combination of the configurations shown in Embodiments 1 to 4 as appropriate. They can be used together.

[0227] As described above, the light-emitting device equipped with the light-emitting device described in Embodiment 1 and Embodiment 2 is suitable for Its range of applications is extremely wide, and this light-emitting device can be applied to electronic equipment in all fields. By using the light-emitting devices described in Embodiment 1 and Embodiment 2, reliability can be improved. You can obtain high-end electronic devices.

[0228] Figure 7(A) is a schematic diagram showing an example of a cleaning robot.

[0229] The cleaning robot 5100 has a display 5101 located on the top and multiple displays located on the sides. It has several cameras 5102, brushes 5103, and operation buttons 5104. However, the underside of the 5100 cleaning robot is equipped with wheels, a suction port, etc. The 5100 robot also includes an infrared sensor, ultrasonic sensor, acceleration sensor, and piezo sensor. It is equipped with various sensors such as optical sensors and gyro sensors. Also, the cleaning robot 5 Unit 100 is equipped with wireless communication means.

[0230] The cleaning robot 5100 moves autonomously, detects the dirt 5120, and uses the suction port located on its underside to... It can then vacuum up the dust.

[0231] Furthermore, the cleaning robot 5100 analyzes images captured by the camera 5102, and detects walls, furniture, or It can determine the presence or absence of obstacles such as steps. Furthermore, image analysis can detect wiring and other obstacles. If an object that may become entangled in brush 5103 is detected, the rotation of brush 5103 will be stopped. can.

[0232] The display 5101 displays information such as the battery level and the amount of dust collected. This is possible. The path taken by the cleaning robot 5100 can be displayed on the display 5101. Good. Also, the display 5101 is a touch panel, and the operation buttons 5104 are on the display. It may also be provided at Ray 5101.

[0233] The cleaning robot 5100 can communicate with portable electronic devices 5140 such as smartphones. Yes, it is possible. Images captured by camera 5102 can be displayed on the portable electronic device 5140. Therefore, the owner of the 5100 cleaning robot can know what's happening in the room even when they're away from home. It is possible to display the information on the display 5101 on portable electronic devices such as smartphones. You can also check it there.

[0234] A light-emitting device according to one aspect of the present invention can be used in a display 5101.

[0235] The robot 2100 shown in Figure 7(B) consists of a computing unit 2110, an illuminance sensor 2101, and a microphone. Lophone 2102, upper camera 2103, speaker 2104, display 2105, bottom It is equipped with a camera 2106, an obstacle sensor 2107, and a moving mechanism 2108.

[0236] Microphone 2102 has the function of detecting the user's voice and ambient sounds, etc. Speaker 2104 has the function of emitting sound. Robot 2100 has a microphone Using the 2102 and speaker 2104, communication with the user is possible. It is possible.

[0237] The display 2105 has the function of displaying various information. The robot 2100 is The user can display the desired information on the display 2105. The 2105 may have a touch panel. Also, the display 2105 is removable. It can be an information terminal capable of charging, and by installing it in a fixed position on the robot 2100, And it enables the transfer of data.

[0238] The upper camera 2103 and lower camera 2106 are used to image the area around the robot 2100. It has the ability to detect obstacles. Furthermore, the obstacle sensor 2107 uses the moving mechanism 2108 to detect robot 210 Robot 21 can detect the presence or absence of obstacles in the direction of travel as it moves forward. 00 uses the upper camera 2103, the lower camera 2106 and the obstacle sensor 2107 The light-emitting device according to one aspect of the present invention can recognize its surroundings and move safely. It can be used in display 2105.

[0239] Figure 7(C) shows an example of a goggle-type display. For example, the housing 5000, the display unit 5001, the speaker 5003, the LED lamp 5004, Connection terminal 5006, sensor 5007 (force, displacement, position, velocity, acceleration, angular velocity, rotational speed, Distance, light, liquid, magnetism, temperature, chemicals, sound, time, hardness, electric field, electric current, voltage, power, radiation (including functions for measuring radiation, flow rate, humidity, gradient, vibration, odor, or infrared radiation), It includes a crossphone 5008, a display unit 5002, a support unit 5012, an earphone 5013, and the like.

[0240] The light-emitting device according to one aspect of the present invention can be used in the display unit 5001 and the display unit 5002. .

[0241] Figure 8 shows the light-emitting devices described in Embodiments 1 and 2, which are electrical lighting devices. This is an example of its use in a lamp stand. The lamp stand shown in Figure 8 consists of a housing 2001 and a light source 2002. The light source 2002 may be the lighting device described in Embodiment 3.

[0242] Figure 9 shows the light-emitting devices described in Embodiments 1 and 2, in an indoor lighting device 30 This is an example of use as 01. The light-emitting devices described in Embodiment 1 and Embodiment 2 are Because it is a highly reliable light-emitting device, it can be used to create a highly reliable lighting system. Since the light-emitting devices described in Embodiments 1 and 2 can be made to have a large area, It can be used as an area lighting device. Furthermore, as described in Embodiment 1 and Embodiment 2... Because the light-emitting device is thin, it can be used as a miniaturized lighting device. ru.

[0243] The light-emitting devices described in Embodiments 1 and 2 are used on the windshields and windows of automobiles. It can also be mounted on a dashboard. Figure 10 shows Embodiments 1 and 2. This shows one embodiment of using the light-emitting device on the windshield or dashboard of an automobile. Display areas 5200 to 5203 are light-emitting devices as described in Embodiments 1 and 2. This is a display area provided using a vise.

[0244] Display area 5200 and display area 5201 are in an embodiment provided on the windshield of an automobile. This is a display device equipped with the light-emitting device described in Embodiment 1 and Embodiment 2. Embodiment 1 The light-emitting device described in Embodiment 2 is made by fabricating the anode and cathode with light-transmitting electrodes. This allows the display device to be made transparent, allowing the other side to be seen through, creating a so-called see-through display. Yes, it's possible. If it's a see-through display, it can be installed on a car's windshield. It can be installed without obstructing the view. Note that it requires transistors for operation, etc. When providing an organic transistor, an organic transistor made of organic semiconductor material or a transistor made of oxide semiconductor material may be used. It is advisable to use transistors that are transparent to light, such as transistors.

[0245] The display area 5202 is provided in the pillar portion as described in Embodiments 1 and 2. This is a display device equipped with an optical device. The display area 5202 is an imaging device provided on the vehicle body. By displaying images from the steps, the view obstructed by the pillars can be compensated for. Similarly, the display area 5203 located on the dashboard is obstructed by the vehicle body. The blind spots are compensated for by displaying images from an imaging device mounted on the outside of the vehicle. It can supplement and enhance safety. By projecting images to complement the parts that are not visible, This allows for a more natural and seamless safety check.

[0246] Display area 5203 also displays navigation information, speedometer, tachometer, odometer, fuel gauge, and gear. By displaying status, air conditioning settings, etc., various information can be provided. The display items and layout can be changed as needed to suit the user's preferences. This information can also be provided in display areas 5200 to 5202. Areas 5200 to 5203 can also be used as lighting devices.

[0247] Figures 11(A) to (C) also show a foldable portable information terminal 9310. Figure 11 (A) shows the portable information terminal 9310 in its unfolded state. Figure 11(B) shows the unfolded state or This shows the portable information terminal 9310 in an intermediate state, transitioning from one folded state to the other. Figure 11(C) shows the folded state of the personal digital assistant 9310. Personal digital assistant 9310 It offers excellent portability when folded and a seamless, wide display area when unfolded. This provides excellent readability in the display.

[0248] The display panel 9311 is supported by three housings 9315 connected by hinges 9313. The display panel 9311 is a touch panel equipped with a touch sensor (input device). It may also be an input / output device. In addition, the display panel 9311 is connected via the hinge 9313. By bending the two housings 9315, the mobile information terminal 9310 is unfolded. It can be reversibly transformed from a folded state. A light-emitting device according to one aspect of the present invention It can be used with the display panel 9311.

[0249] Figures 12(A) and (B) also show a foldable portable information terminal 5150. The portable information terminal 5150 consists of a housing 5151, a display area 5152, and a bendable portion 515 It has 3. Figure 12(A) shows the portable information terminal 5150 in its unfolded state. Figure 12( B) shows the portable information terminal 5150 in its folded state. The portable information terminal 5150 is large Despite having a large display area of ​​5152, it folds up compactly and is highly portable.

[0250] The display area 5152 can be folded in half by the bending portion 5153. Bending portion 515 3 consists of an expandable member and multiple support members, and when folded, the expandable The member stretches, and the bent portion 5153 has a radius of curvature of 2 mm or more, preferably 3 mm or more. It folds up.

[0251] Note that the display area 5152 is a touch panel (input / output) equipped with a touch sensor (input device). It may also be a device. The light-emitting device according to one aspect of the present invention can be used in the display area 5152. Cut. [Examples]

[0252] In this embodiment, a light-emitting device 1, which is a light-emitting device according to one aspect of the present invention, and a comparative light-emitting device The fabrication method and characteristics of comparative light-emitting device 1 are shown. In light-emitting device 1, electron A first skeleton with transport properties, a second skeleton that accepts holes, and a monocyclic and π-electron-deficient compound As an electron transport material having a third skeleton which is an aromatic ring, 2-phenyl-3-{4-[ 10-(3-pyridyl)-9-antryl]phenyl}quinoxaline (abbreviation: PyA1P) Q) is a light-emitting device having an electron transport layer. For comparison, PyA1 Replace PQ with 2-{4-[9,10-di(naphthalene-2-yl)-2-antryl]f Luminescent light using phenyl-1-phenyl-1H-benzimidazole (abbreviation: ZADN) This is a vise. The structural formula of the material used in this embodiment is shown below.

[0253] [ka]

[0254] ≪Method for fabricating light-emitting device 1≫ First, indium tin oxide (ITSO) containing silicon oxide is sputtered onto a glass substrate. A film was deposited using the 3D method to form the anode 101. The film thickness was 70 nm, and the electrode area was 4 mm 2 (2mm x 2mm)

[0255] Next, as a pretreatment for forming a light-emitting device on the substrate, the substrate surface is washed with water, and 2 After firing at 0°C for 1 hour, UV ozone treatment was performed for 370 seconds.

[0256] Then, 10 -4 A substrate is introduced into a vacuum deposition apparatus where the internal pressure is reduced to approximately Pa, and then vacuum deposition is performed. After vacuum firing at 170°C for 30 minutes in the heating chamber of the apparatus, the substrate is left for approximately 30 minutes. It was allowed to cool.

[0257] Next, the substrate on which the anode 101 is formed is turned so that the surface with the anode 101 is facing downwards. The substrate is fixed to a substrate holder provided inside the vapor deposition apparatus, and vapor deposition is carried out on the anode 101 using resistance heating. N,N-bis(4-biphenyl)-6-phenyl represented by the above structural formula (i) is obtained by the bonding method. Benzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf) and AL D-MP001Q (Analysis Workshop Co., Ltd., Material serial number: 1S20180314) , such that the weight ratio is 1:0.1 (=BBABnf:ALD-MP001Q), 10n A hole injection layer 111 was formed by co-deposition. Note that ALD-MP001Q is an acceptor. It is an organic compound having [a certain characteristic].

[0258] Next, BBABnf is added to the hole injection layer 111 as the first hole transport layer 112-1. After deposition to a size of nm, the second hole transport layer 112-2 is formed using the above structural formula (ii). Represented as 3,3'-(naphthalene-1,4-diyl)bis(9-phenyl-9H-cal) A hole transport layer 112 is formed by depositing a bazole (abbreviated as PCzN2) to a thickness of 10 nm. Success. Furthermore, the second hole transport layer 112-2 also functions as an electron blocking layer.

[0259] Next, the 9-(1-naphthyl)-10-[4-(2-naphthyl] represented by the above structural formula (iii) [Phthyl)phenyl]anthracene (abbreviation: αN-βNPAnth) and the above structural formula (iv) Represented by 3,10-bis[N-(9-phenyl-9H-carbazol-2-yl)-N -phenylamino]naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3, 10PCA2Nbf(IV)-02) and a weight ratio of 1:0.015 (=αN-βNPAn A 25nm co-deposited layer was created so that the th:3,10PCA2Nbf(IV)-02) would form the emissive layer. Formed 113.

[0260] Subsequently, on the light-emitting layer 113, 2-phenyl-3-{4-[1 0-(3-pyridyl)-9-antryl]phenyl}quinoxaline (abbreviation: PyA1PQ) ) and 8-hydroxyquinolinato-lithium (abbreviated as Liq) represented by the above structural formula (vi). After co-depositing ) and 12.5 nm with a weight ratio of 1:2 (=PyA1PQ:Liq) Co-deposited at 12.5 nm with a weight ratio of 2:1 (=PyA1PQ:Liq), and electron transport A transport layer 114 was formed.

[0261] After forming the electron transport layer 114, aluminum is deposited to a thickness of 200 nm. By doing so, the cathode 102 was formed and the light-emitting device 1 of this embodiment was fabricated.

[0262] ≪Method for fabricating comparative light-emitting device 1≫ Comparative light-emitting device 1 uses PyA1PQ in light-emitting device 1 as shown in structural formula (vii) above. Represented as 2-{4-[9,10-di(naphthalene-2-yl)-2-anthryl]fer The only change made was to 'nyl'-1-phenyl-1H-benzimidazole (abbreviation: ZADN). It was fabricated in the same manner as optical device 1.

[0263] The device structures of light-emitting device 1 and comparative light-emitting device 1 are summarized in the table below.

[0264] [Table 1]

[0265] These light-emitting devices are placed in a glove box under a nitrogen atmosphere, and the light-emitting devices are exposed to the atmosphere. The process of sealing the element with a glass substrate to prevent exposure to sunlight (applying a sealing material around the element and sealing it) After UV treatment and heat treatment at 80°C for 1 hour (at the stop), the light-emitting device 1 and the comparison light-emitting device are subjected to UV treatment and heat treatment at 80°C for 1 hour. The initial characteristics and reliability of device 1 were measured. The measurements were performed at room temperature.

[0266] Figure 13 shows the luminance-current density characteristics of light-emitting device 1 and comparative light-emitting device 1, and the current efficiency-luminance characteristics. The luminance characteristics are shown in Figure 14, the luminance-voltage characteristics in Figure 15, and the current-voltage characteristics in Figure 16. External quantum effects The rate-luminance characteristics are shown in Figure 17, and the emission spectrum is shown in Figure 18. Also, the light-emitting device 1 and Comparative light-emitting device 1: 1000 cd / m² 2 Table 2 shows the main characteristics of the vicinity.

[0267] [Table 2]

[0268] As shown in Figures 13 to 18 and Table 2, the light-emitting device 1, which is one embodiment of the present invention, has good initial characteristics. It was found to be a blue light-emitting device with properties.

[0269] Furthermore, the current density is 50 mA / cm². 2 The graph shows the change in brightness with respect to operating time. As shown in Figure 19, a light-emitting device 1 is a light-emitting device according to one aspect of the present invention. Compared to comparative light-emitting device 1, the long-term slope after the initial changes have subsided is smaller. It was found to be a light-emitting device with a good lifespan and minimal long-term degradation.

[0270] Furthermore, the light-emitting device 1 and the comparative light-emitting device 1 have a hole injection layer that has hole transport properties, H BBABnf with an OMO level between -5.7eV and -5.4eV, and BBABnf It has an electron-accepting ALD-MP001Q, and also has a metal, metal salt, and gold in its electron transport layer. It contains Liq, which is a group oxide or organometallic salt.

[0271] As a result, the brightness of light-emitting device 1 and comparison light-emitting device 1 increases after operation, and the initial brightness It shows a higher brightness than that and then gradually decreases. This means that the initial brightness is particularly based on This significantly extends the time it takes for the battery to degrade by 2-5% (initial operating life).

[0272] As mentioned above, the light-emitting device 1 exhibits a very good lifespan due to its minimal long-term degradation. It was found to be a light-emitting device. [Examples]

[0273] <<Synthesis Example 1>> In this synthesis example, it is possible to use it as an electron transport material for a light-emitting device according to one embodiment of the present invention. The compound 4-{4-[10-(3-pyridyl)-9-anthryl]phenyl}[1] This article explains the synthesis method of benzoflo[3,2-d]pyrimidine (abbreviated as BfpmPPyA). Let me clarify. The structure of BfpmPPyA is shown below.

[0274] [ka]

[0275] Step 1: 4-(4-chlorophenyl)[1]benzoflo[3,2-d]pyrimidine Synthesis of > 4-Chloro[1]benzoflo[3,2-d]pyrimidine 2.0g (9.7 mmol), 4 - 1.8g (12 mmol) of chlorophenylboronic acid, tri(ortho-tolyl)phosphine 0.30g (0.97 mmol) of potassium carbonate and 2.7g (19 mmol) of potassium carbonate are mixed in three mouthfuls. I put it in a container. To this mixture, I added 100 mL of toluene, 20 mL of ethanol, and 10 mL of water. Then, the mixture was stirred under reduced pressure to remove air. Finally, 0.044 g of palladium(II) acetate was added to the mixture. (0.19 mmol) was added and the mixture was stirred at 80°C for 6 hours. Furthermore, palladium acetate (II) was added. 0.027g (0.097 mmol), tri(ortho-tolyl)phosphine 0.20g (0.44 mmol) was added and the mixture was stirred at 80°C for 2 hours.

[0276] After stirring, water was added to the mixture, the aqueous layer was separated, and the organic layer was filtered. Furthermore, the aqueous layer was... Extraction was performed with Luen. The obtained extract solution and the previous filtrate were combined and washed with water, and the organic layer was treated with sulfate. It was dried with magnesium. This mixture was filtered by natural filtration, and the filtrate was concentrated. The solid was then subjected to silica gel column chromatography (eluent: toluene:ethyl acetate = 9 The product was purified by :1) and a pale yellow solid of the target product was obtained in a yield of 2.5 g and 92%. The reaction scheme for step 1 is shown below.

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[0278] <Step 2: 4-[4-(4,4,5,5-tetramethyl-[1,3,2]dioxabond Synthesis of loran-2-yl)phenyl][1]benzoflo[3,2-d]pyrimidine 4-(4-chlorophenyl)[1]benzoflo[3,2-d]pyrimidine 2.5g (8. 9 mmol), bispinacholate diborone 2.7 g (11 mmol), potassium acetate 2. 6 g (27 mmol) and 45 mL of xylene were placed in a three-necked flask and purged with nitrogen. The compound contains [1,1'-bis(diphenylphosphino)ferrocene]palladium(II) dik Lorid dichloromethane adduct (abbreviation: Pd(dppf)Cl2) · CH2Cl2)0.3 6g (0.44 mmol) was added and stirred at 120°C for 17 hours.

[0279] After stirring, toluene and water were added to the mixture, and the solution was filtered. The organic layer of the resulting filtrate was removed. The aqueous layer was then extracted with toluene. The resulting extract and the organic layer were washed together with water, and the organic layer was then removed. The layers were dried with magnesium sulfate. This mixture was filtered by natural filtration, and the filtrate was concentrated. The obtained solid was dissolved in toluene and filtered through Celite, Fluorizil, and alumina. The mixture was passed through (solvent:toluene:ethyl acetate = 4:1). The filtrate was concentrated, and the resulting solid was silica. Purification by gel column chromatography (eluent: toluene:ethyl acetate = 3:1) Then, the target yellow solid was obtained in a yield of 2.6 g and 79%. Synthesis scheme of Step 2 The following is shown.

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[0281] <Step 3: 4-{4-[10-(3-pyridyl)-9-anthryl]phenyl}[1 Synthesis of benzoflo[3,2-d]pyrimidine (abbreviation: BfpmPPyA) 1.6 g of 3-(10-bromo-9-anthryl)pyridine in a 200 mL three-necked flask. 4.8 mmol) and 4-[4-(4,4,5,5-tetramethyl-[1,3,2]dioxy Saborolan-2-yl)-phenyl]-[1]benzofloflo[3,2-d]pyrimidine 2. 0g (5.3 mmol), tri(o-tolyl)phosphine 0.15g (0.48 mmol) ), 1.3 g (9.6 mmol) of potassium carbonate was added and the flask was purged with nitrogen. This mixture Add 50 mL of toluene, 10 mL of ethanol, and 5 mL of water to the mixture and stir under reduced pressure. The mixture was degassed. 22 mg (0.096 mmol) of palladium(II) acetate was added to this mixture. The mixture was then stirred under a nitrogen stream at 80°C for 11 hours. After the specified time had elapsed, water was added to the mixture. The precipitated solid was recovered by suction filtration and washed with water and methanol. Silica gel column chromatography (eluent: toluene:ethyl acetate = 9:1) After purification and recrystallization with toluene, 1.4 g (2.8 mm) of the target solid was obtained. (ol), obtained in 57% yield. The synthesis scheme for Step 3 is shown below.

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[0283] The obtained solid (1.3 g) was purified by sublimation using the train sublimation method. Sublimation purification was performed using the train sublimation method. The procedure was performed under conditions of a pressure of 3.0 Pa, an argon flow rate of 5 mL / min, and a temperature of 275°C. After sublimation purification, 1.2 g of BfpmPPyA powder was obtained with a recovery rate of 91%.

[0284] Nuclear magnetic resonance spectroscopy of the obtained compound ( 1 The measurement results by H-NMR are shown in Figure 25(A)(B)(B). The numerical data is shown below. 1 1H NMR (CDCl3, 300MHz): δ=7. 36-7.44(m,4H), 7.54-7.69(m,4H), 7.73-7.89( m,7H), 8.37(d,J=7.7Hz,1H), 8.77(dd,J=2.2Hz ,0.7Hz,1H), 8.83-8.91(m,3H), 9.36(s,1H). This This indicates that BfpmPPyA was obtained in this synthesis example. [Examples]

[0285] ≪Synthesis Example 2≫ In this synthesis example, it is possible to use it as an electron transport material for a light-emitting device according to one embodiment of the present invention. The compound is 2-{4-[10-(3-pyridyl)-9-anthryl]phenyl}dibene This document describes the synthesis method of zo[f,h]quinoxaline (abbreviation: DBqPPyA). The structure of qPPyA is shown below.

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[0287] <Step 1: 2-{4-[10-(3-pyridyl)-9-anthryl]phenyl}dibe Synthesis of nz[f,h]quinoxaline (abbreviation: DBqPPyA) 1.1 g of 3-(10-bromo-9-anthryl)pyridine in a 150 mL three-necked flask. 3.2 mmol) and 2-(4,4,5,5-tetramethyl-1,3,2-dioxavorola) (2-yl)dibenzo[f,h]quinoxaline 1.5g (3.5mmol), tri(o Lutotril)phosphine 96mg (0.32 mmol), potassium carbonate 0.87g (6 Add 0.3 mmol) and purge the flask with nitrogen. Add 30 mL of toluene and ethanol to this mixture. 6.0 mL of NOL and 3.0 mL of water were added, and the mixture was degassed by stirring under reduced pressure. Add 14 mg (0.063 mmol) of palladium(II) acetate to the mixture and, under a nitrogen stream, 8 The mixture was stirred at 0°C for 21 hours. After the specified time, water was added to the mixture, and the solid was removed by suction filtration. The material was recovered. Toluene was added to the obtained solid, and after irradiation with ultrasound, the solid was recovered.

[0288] The obtained solid is subjected to silica gel column chromatography (eluent: chloroform). After purification and recrystallization in a mixed solvent of toluene and ethanol, the target solid was obtained at 0 0.96 g was obtained in 55% yield. The synthesis scheme for Step 1 is shown below.

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[0290] The obtained solid 0.96 g was purified by sublimation using the train sublimation method. The procedure was performed under conditions of a pressure of 2.9 Pa, an argon flow rate of 5 mL / min, and a temperature of 305°C. After sublimation purification, 0.80 g of DBqPPyA powder was obtained with a recovery rate of 82%.

[0291] Nuclear magnetic resonance spectroscopy of the obtained compound ( 1 The measurement results by H-NMR are shown in Figure 26(A)(B) The numerical data is shown below. 1 1H NMR (CDCl3, 300MHz): δ=7. 38-7.45(m,4H), 7.57-7.69(m,3H), 7.72-7.91( m,9H), 8.63(d,J=8.1Hz,2H), 8.70(d,J=7.7Hz, 2H), 8.77-8.80(m,1H), 8.85(dd,J=1.5Hz,4.8H z,1H), 9.28-9.32(m,1H), 9.49-9.54(m,1H), 9. 57(s,1H). This shows that DBqPPyA was obtained in this synthesis example. . [Examples]

[0292] ≪Synthesis Example 3≫ In this synthesis example, it is possible to use it as an electron transport material for a light-emitting device according to one embodiment of the present invention. The compound is (9-{4-[10-(3-pyridyl)-9-anthryl]phenyl}naph To[1',2':4,5]fl[2,3-b]pyrazine) (abbreviation: NfprPPyA) The synthesis method will be explained. The structure of NfprPPyA is shown below.

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[0294] <Step 1: 9-[4-(4,4,5,5-tetramethyl-[1,3,2]dioxabond [Rolan-2-yl)-phenyl]naphtho[1',2':4,5]flo[2,3-b]pyra Synthesizing gin > 9-(4-chlorophenyl)-naphtho[1',2':4,5]flo[2,3-b]pyrazi 3.2g (9.7mmol), bispinacholate diborone 3.0g (12mmol), Place 2.9 g (29 mmol) of potassium acetate and 50 mL of xylene in a three-necked flask and reduce the pressure. The mixture was stirred and degassed below. [1,1'-bis(diphenylphosphin)ferro [Cen] Palladium(II) dichloromethane adduct (abbreviation: Pd(dppf)Cl2) 0. 40g (0.49 mmol) was added and stirred at 120°C for 19 hours.

[0295] After a predetermined time had elapsed, toluene was added to this mixture. The solution was then treated with Celite, Florizil, The solution was filtered through alumina (solvent toluene:ethyl acetate = 1:1), and the filtrate was concentrated. The obtained solid was subjected to silica gel column chromatography (eluent: toluene:ethyl acetate). The mixture was purified using a 3:1 ratio to obtain a yellow solid. Hexane was added to the obtained solid, and ultrasound was applied. When the solid was collected by suction filtration, the yield of the target yellow solid was 3.7 g, and the yield was... It was obtained with 89% accuracy. The synthesis scheme for Step 1 is shown below.

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[0297] <Step 2: (9-{4-[10-(3-pyridyl)-9-anthryl]phenyl}na Phtho[1',2':4,5]phlo[2,3-b]pyrazine) (abbreviation: NfprPPyA) Synthesis of > 1.4 g of 3-(10-bromo-9-anthryl)pyridine in a 200 mL three-necked flask. 4.1 mmol) and 3-[4-(4,4,5,5-tetramethyl-[1,3,2]dioxy Saborolan-2-yl)-phenyl]naphtho[1',2':4,5]flo[2,3-b] Pyrazine 1.9g (4.5 mmol), Tri(o-tolyl)phosphine 0.13g (0. Add 41 mmol of potassium carbonate (1.1 g, 8.3 mmol) and purge the flask with nitrogen. To this mixture, add 40 mL of toluene, 8 mL of ethanol, and 4 mL of water, and stir under reduced pressure. The mixture was degassed by stirring. 19 mg (0.083 mg) of palladium(II) acetate was added to this mixture. mmol was added and stirred at 80°C for 10 hours under a nitrogen stream. After the predetermined time had elapsed, this mixture Water was added to the substance, and the precipitated solid was recovered by suction filtration. The obtained solid was mixed with water and methanol. The mixture was washed with [a specific solvent]. The resulting solid was subjected to silica gel column chromatography (eluent: toluene). The target product was purified using ethyl acetate (9:1 ratio) and then recrystallized in toluene. 1.3 g (2.4 mmol) of solid was obtained in a yield of 58%. The synthesis scheme of Step 2 was used. See below.

[0298] [ka]

[0299] The obtained solid 1.3 g was purified by sublimation using the train sublimation method. Sublimation purification was performed under pressure. The procedure was performed under conditions of 3.3 Pa, argon flow rate of 15 mL / min, and 320°C. After sublimation purification, 0.94 g of NfprPPyA powder was obtained with a recovery rate of 73%.

[0300] Nuclear magnetic resonance spectroscopy of the obtained compound ( 1 The measurement results by H-NMR are shown in Figure 27(A)(B) The numerical data is shown below. 1 1H NMR (CDCl3, 300MHz): δ=7. 36-7.45(m,4H), 7.56-7.74(m,6H), 7.78-7.91( m,5H), 8.08(d,J=8.1Hz,1H), 8.13(d,J=8.8Hz, 1H), 8.45(d,J=8.4Hz,2H), 8.76-8.78(m,1H), 8 .85(dd,J=4.4Hz,1.5Hz,1H), 9.21(d,J=8.4Hz, 1H), 9.42(s,1H). This yielded NfprPPyA in this synthesis example. It was discovered that... [Examples]

[0301] In this embodiment, light-emitting devices 2 to 4 are light-emitting devices according to one aspect of the present invention. The manufacturing method and characteristics are shown. Light-emitting devices 2 to 4 have electron transport layers containing electrons A first skeleton with transport properties, a second skeleton that accepts holes, and a monocyclic and π-electron-deficient compound It has an electron transport material having a third skeleton which is an aromatic ring. Specifically, the light-emitting device 2 is 4-{4-[10-(3-pyridyl)-9-antryl ]phenyl}[1]benzofl[3,2-d]pyrimidine (abbreviation: BfpmPPyA), Light-emitting device 3 is 2-{4-[10-(3-pyridyl)-9-antryl]phenyl}di Benzo[f,h]quinoxaline (abbreviation: DBqPPyA), light-emitting device 4 is (9-{ 4-[10-(3-pyridyl)-9-anthryl]phenyl}naphtho[1',2':4, This example contains 5) flu[2,3-b]pyrazine) (abbreviated as NfprPPyA). The structural formulas of the materials used are shown below.

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[0303] ≪Method for fabricating light-emitting device 2≫ First, indium tin oxide (ITSO) containing silicon oxide is sputtered onto a glass substrate. A film was deposited using the 3D method to form the anode 101. The film thickness was 70 nm, and the electrode area was 4 mm 2 (2mm x 2mm)

[0304] Next, as a pretreatment for forming a light-emitting device on the substrate, the substrate surface is washed with water, and 2 After firing at 0°C for 1 hour, UV ozone treatment was performed for 370 seconds.

[0305] Then, 10 -4 A substrate is introduced into a vacuum deposition apparatus where the internal pressure is reduced to approximately Pa, and then vacuum deposition is performed. After vacuum firing at 170°C for 30 minutes in the heating chamber of the apparatus, the substrate is left for approximately 30 minutes. It was allowed to cool.

[0306] Next, the substrate on which the anode 101 is formed is turned so that the surface with the anode 101 is facing downwards. The substrate is fixed to a substrate holder provided inside the vapor deposition apparatus, and vapor deposition is carried out on the anode 101 using resistance heating. N,N-bis(4-biphenyl)-6-phenyl represented by the above structural formula (i) is obtained by the bonding method. Benzo[b]naphtho[1,2-d]furan-8-amine (abbreviation: BBABnf) and AL D-MP001Q (Analysis Workshop Co., Ltd., Material serial number: 1S20180314) , such that the weight ratio is 1:0.1 (=BBABnf:ALD-MP001Q), 10n A hole injection layer 111 was formed by co-deposition. Note that ALD-MP001Q is an acceptor. It is an organic compound having [a certain characteristic].

[0307] Next, BBABnf is added to the hole injection layer 111 as the first hole transport layer 112-1. After deposition to a size of nm, the second hole transport layer 112-2 is formed using the above structural formula (ii). Represented as 3,3'-(naphthalene-1,4-diyl)bis(9-phenyl-9H-cal) A hole transport layer 112 is formed by depositing a bazole (abbreviated as PCzN2) to a thickness of 10 nm. Success. Furthermore, the second hole transport layer 112-2 also functions as an electron blocking layer.

[0308] Next, the 9-(1-naphthyl)-10-[4-(2-naphthyl] represented by the above structural formula (iii) [Phthyl)phenyl]anthracene (abbreviation: αN-βNPAnth) and the above structural formula (iv) Represented by 3,10-bis[N-(9-phenyl-9H-carbazol-2-yl)-N -phenylamino]naphtho[2,3-b;6,7-b']bisbenzofuran (abbreviation: 3, 10PCA2Nbf(IV)-02) and a weight ratio of 1:0.015 (=αN-βNPAn A 25nm co-deposited layer was created so that the th:3,10PCA2Nbf(IV)-02) would form the emissive layer. Formed 113.

[0309] Subsequently, on the light-emitting layer 113, 4-{4-[10-(3 [-pyridyl)-9-antryl]phenyl}[1]benzoflo[3,2-d]pyrimidine (Abbreviation: BfpmPPyA) and 8-hydroxyquinolinate represented by the above structural formula (vi) -The weight ratio of lithium (abbreviated as Liq) to Lithium is 1:2 (=BfpmPPyA:Liq). A 25nm co-deposited layer was used to form an electron transport layer 114.

[0310] After forming the electron transport layer 114, aluminum is deposited to a thickness of 200 nm. By doing so, the cathode 102 was formed and the light-emitting device 2 of this embodiment was fabricated.

[0311] ≪Method for fabricating light-emitting device 3≫ Light-emitting device 3 uses BfpmPPyA in light-emitting device 2 with the above structural formula (ix) The expressed 2-{4-[10-(3-pyridyl)-9-anthryl]phenyl}dibenzo[ Aside from being changed to quinoxaline (abbreviation: DBqPPyA) in f,h, it is the same as light-emitting device 2. I made it.

[0312] ≪Method for fabricating light-emitting device 4≫ The light-emitting device 4 represents the electron transport layer 114 in the light-emitting device 2 using the above structural formula (x). (9-{4-[10-(3-pyridyl)-9-anthryl]phenyl}naphtho[1 ',2':4,5]Flo[2,3-b]pyrazine) (abbreviation: NfprPPyA) and Liq The two materials were co-deposited at a 12.5 nm thickness with a weight ratio of 1:2 (=NfprPPyA:Liq). Next, a 12.5nm co-deposit was performed so that the weight ratio was 2:1 (=NfprPPyA:Liq). Aside from the formation process, it was fabricated in the same manner as light-emitting device 2.

[0313] The device structures of light-emitting devices 2 through 4 are summarized in the table below.

[0314] [Table 3]

[0315] These light-emitting devices are placed in a glove box under a nitrogen atmosphere, and the light-emitting devices are exposed to the atmosphere. The process of sealing the element with a glass substrate to prevent exposure to sunlight (applying a sealing material around the element and sealing it) After UV treatment and heat treatment at 80°C for 1 hour, the light-emitting device 2 or light-emitting device The initial characteristics and reliability of S4 were measured. The measurements were taken at room temperature.

[0316] Figure 28 shows the luminance-current density characteristics of light-emitting devices 2 to 4, and the current efficiency-luminance characteristics. The properties are shown in Figure 29, the brightness-voltage characteristics in Figure 30, the current-voltage characteristics in Figure 31, and the external quantum efficiency- The luminance characteristics are shown in Figure 32, and the emission spectrum is shown in Figure 33. Furthermore, the light-emitting devices 2 to light-emitting devices Vice 4 1000 cd / m 2 Table 4 shows the main characteristics of the vicinity.

[0317] [Table 4]

[0318] Figures 28 to 33 and Table 4 show one embodiment of the present invention: Light-emitting device 2 to Light-emitting device Device 4 was found to be a blue light-emitting device with good initial characteristics.

[0319] Furthermore, the current density is 50 mA / cm². 2 The graph shows the change in brightness with respect to operating time. As shown in Figure 34, a light-emitting device 2 is a light-emitting device according to one aspect of the present invention. Alternatively, the light-emitting device 4 has a small long-term slope after the initial changes have subsided, and exhibits little long-term degradation. It was found to be a high-quality light-emitting device with an excellent lifespan.

[0320] Furthermore, the light-emitting devices 2 to 4 have a hole injection layer that has hole transport properties, and HOMO A BBABnf with an energy level between -5.7eV and -5.4eV, and an electron-receiving BBABnf. It has ALD-MP001Q which exhibits tolerance, and also has a metal, metal salt, and metal oxide in the electron transport layer. It contains Liq, which is a substance or an organometallic salt.

[0321] As a result, the brightness of the light-emitting device 3 increases after being driven, and then gradually decreases. This results in a time (initial operating life) during which the brightness deteriorates by 2-5% relative to the initial brightness. It can be significantly increased.

[0322] (Reference example 1) In this reference example, the HOMO level, LUMO level, and electron transfer of the organic compounds used in each example are shown. I will now explain how to calculate the degree of motion.

[0323] HOMO and LUMO levels are calculated based on cyclic voltammetry (CV) measurements. It is possible.

[0324] The measuring device used is an electrochemical analyzer (manufactured by BAS Corporation, model number: ALS model). A 600A or 600C was used. The solution used in the CV measurement was dehydrated dimethyl as the solvent. Aldrich Formamide (DMF) (manufactured by Aldrich Co., Ltd., 99.8%, catalog number; 227) Using 05-6), the supporting electrolyte is tetra-n-butylammonium perchlorate (nB u4NClO4) (manufactured by Tokyo Chemical Co., Ltd., catalog number: T0836) 100 mmol / Dissolve to a concentration of L, and then dissolve the sample to be measured to a concentration of 2 mmol / L. It was prepared by dissolving it. Furthermore, a platinum electrode (manufactured by BAS Corporation, PT) was used as the working electrode. E Platinum electrode) is used as an auxiliary electrode, and platinum electrode (manufactured by B.A.S. Co., Ltd., for VC-3 P A counter electrode (5 cm) is used, and an Ag / Ag+ electrode (B.A.A.E.) is used as the reference electrode. A RE7 non-aqueous solvent reference electrode manufactured by S Corporation was used. The measurements were taken at room temperature (20°C). The measurements were performed at 25°C. The scan speed during CV measurement was standardized to 0.1V / sec. The oxidation potential Ea [V] and reduction potential Ec [V] were measured relative to the irradiated electrode. Ea is the oxidation- The intermediate potential of the reduction wave was used, and Ec was set as the intermediate potential of the reduction-oxidation wave. Here, the values ​​used in this embodiment The potential energy of the reference electrode relative to the vacuum level is -4.94 [eV]. Since it is known that the HOMO level [eV] = -4.94 - Ea, the LUMO level [eV The HOMO level and LUMO level can be determined from the equation ] = -4.94 - Ec. It is possible.

[0325] Electron mobility is measured by impedance spectroscopy. It can be measured using the IS method.

[0326] The carrier mobility of EL materials is measured using transient photocurrent (Time-of-flight:T) spectroscopy. OF method and space-charge-limited current Methods such as the SCLC method, which is derived from the IV characteristics of nt (SCLC), have been known for a long time. The TOF method requires a sample with a considerably thicker film thickness compared to actual organic EL elements. The LC method has drawbacks such as not being able to obtain the electric field strength dependence of carrier mobility. Because the thickness of the organic film required for measurement is thin, around several hundred nanometers, even a relatively small amount of EL material can be used. Its key features include the ability to deposit thin films and measure mobility with film thicknesses close to those of actual EL elements. Therefore, the electric field strength dependence of carrier mobility can also be obtained.

[0327] In the IS method, a small sinusoidal voltage signal (V=V0[exp(jωt)]) is applied to the EL element. The current amplitude of the response current signal (I=I0exp[j(ωt+φ)]) and the phase of the input signal From the difference, we can find the impedance of the EL element (Z=V / I). Low frequency voltage from high frequency voltage. By changing it to this extent and applying it to the element, it has various relaxation times that contribute to the impedance. The components can be separated and measured.

[0328] Here, the admittance Y (=1 / Z), which is the reciprocal of impedance, is given by the following equation (1): It can be expressed in terms of conductance G and susceptance B.

[0329]

number

[0330] Furthermore, the single-charge injection model shows that, respectively, Equations (2) and (3) can be calculated. Here, g (equation (4)) is the differential conductor. This is tance. In the formula, C is capacitance, θ is ωt, and the travel angle is... ω represents the angular frequency. t is the travel time. The analysis involves the current equation, Poisson's equation, and current continuity. The equation used ignores the existence of diffusion current and trap levels.

[0331]

number

[0332] The -ΔB method is a method for calculating mobility from the frequency characteristics of capacitance. The ωΔG method is a method for calculating mobility from the frequency characteristics of a device.

[0333] In practice, first, a measuring element is fabricated for the material whose electron mobility is to be determined. The measuring element is made of a ki Designed so that only electrons flow as a carrier. In this specification, the frequency characteristics of capacitance are Next, we will explain the method for calculating mobility (-ΔB method). A schematic diagram of the measuring element used is shown in Figure 20. show.

[0334] The structure of the measuring element fabricated for this measurement is as shown in Figure 20, consisting of an anode 201 and a cathode 2 Between 02 there are a first layer 210, a second layer 211, and a third layer 212. Electron mobility The desired material can be used as the material for the second layer 211. In this case, ZADN and Liq 1 This will be explained using an example of measuring the electron mobility of a co-evaporated film with a weight ratio of :1. Typical configuration examples are summarized in the table below.

[0335] [Table 5]

[0336] Current density of a measuring element fabricated with a co-evaporated film of ZADN and Liq as the second layer 211. The pressure characteristics are shown in Figure 21.

[0337] Impedance measurement is performed by applying a DC voltage in the range of 5.0V to 9.0V while simultaneously measuring the AC voltage. Measurements were taken under the conditions of 70mV and a frequency of 1Hz to 3MHz. The impedance obtained here Capacitance is calculated from admittance (equation (1) above), which is the reciprocal of dance. Figure 22 shows the frequency characteristics of the calculated capacitance C at an applied voltage of 7.0V.

[0338] The frequency characteristics of capacitance C are determined by the spatial charge of carriers injected by a small voltage signal. This is obtained when the load cannot fully follow the minute AC voltage, resulting in a phase difference in the current. Here, the travel time of the carriers in the membrane is the time T it takes for the injected carriers to reach the counter electrode. It is defined and expressed by the following equation (5).

[0339]

number

[0340] The negative susceptance change (-ΔB) is the value obtained by multiplying the capacitance change -ΔC by the angular frequency ω (-ωΔ). This corresponds to C). Its lowest frequency peak frequency is f'. max (=ω max ( / 2π) and run From equation (3), the following relationship (6) can be derived between row time T and row time.

[0341]

number

[0342] Figure 2 shows the frequency characteristics of -ΔB calculated from the above measurements (i.e., when the DC voltage is 7.0V). As shown in 3, the lowest frequency peak frequency f' can be determined from Figure 23. max This is indicated by the arrow in the diagram. did.

[0343] f' obtained from the above measurements and analysis max Therefore, the travel time T can be determined (using the above formula ( 6) See also), from equation (5) above, we can determine the electron mobility at a voltage of 7.0V in this case. This can be done. By performing similar measurements in the DC voltage range of 5.0V to 9.0V, each voltage can be determined. Since electron mobility can be calculated at (electric field strength), the dependence of mobility on electric field strength can also be measured.

[0344] Using the calculation methods described above, the final electron mobility of each organic compound depends on the electric field strength. Figure 24 shows the values, and the square root of the electric field strength [V / cm] read from the figure is 600 [V / cm]. 1 / 2 Table 6 shows the electron mobility values ​​for each of these conditions.

[0345] [Table 6]

[0346] As described above, it is possible to calculate electron mobility. For detailed measurement methods, please refer to the following. Takayuki Okachi et al. "Japanese Journal of Applied Physics” Vol. 47, No. 12, 2008, Please refer to pp. 8965-8972.

[0347] (Reference example 2) <<Synthesis Example 4>> In this reference example, the 2-phenyl-3-{4-[10-(3-pyridinyl) used in Example 1 Regarding the synthesis method of [Lu-9-antryl]phenyl}quinoxaline (abbreviation: PyA1PQ) Let me explain. The structure of PyA1PQ is shown below.

[0348] [ka]

[0349] 0.74g of 3-(10-bromo-9-anthryl)pyridine (2) in a 50mL three-necked flask. 0.2 mmol), tri(ortho-tril)phosphine 0.26 g (0.85 mmol), 4-(3-phenylquinoxaline-2-yl)phenylboronic acid 0.73g (2.3mm) 1.3g (9.0 mmol) potassium carbonate aqueous solution, ethylene glycol dimethyl Add 40 mL of ether (DME) and 4.4 mL of water. Stir this mixture under reduced pressure. The flask was then degassed and the contents were replaced with nitrogen.

[0350] Add 65 mg (0.29 mmol) of palladium(II) acetate to the mixture in this flask. The mixture was stirred at 80°C for 11 hours under a nitrogen stream. After stirring, water was added to the mixture in the flask. Extraction was performed with Luen. The resulting extract was washed with saturated saline solution and dried with magnesium sulfate. This was then filtered naturally, and the filtrate was concentrated to obtain an oily substance. The obtained oily substance was then placed in silica gel. Column chromatography was performed twice, once with chloroform and once with toluene:ethyl acetate in a 5:1 ratio. The product was purified and recrystallized with toluene / hexane to obtain a yellow solid of the target product in a yield of 0.43 g and 36% yield. It was obtained as a percentage. The synthesis scheme is shown in the following formula.

[0351] [ka]

[0352] The resulting yellow solid (0.44 g) was purified by sublimation using the train sublimation method. Purification was performed at a pressure of 10 Pa, an argon flow rate of 5.0 mL / min, and 260°C for 18 hours. The procedure was carried out under thermal conditions. After sublimation purification, 0.35 g of the target substance was obtained as a yellow solid with a recovery rate of 79%.

[0353] Furthermore, nuclear magnetic resonance spectroscopy of the yellow solid obtained from the above reaction ( 1 Analysis results by 1H-NMR The results are shown below. From these results, in this embodiment, PyA1PQ represented by the above structural formula It was found that this was obtained.

[0354] 1 H NMR(CDCl3,300MHz):δ=7.37-7.50(m,9H), 7 .56-7.78(m,9H), 7.82-7.86(m,3H), 8.24-8.30 (m,2H), 8.75(dd,J=1.8Hz,0.9Hz,1H), 8.84(dd (J=4.8Hz, 1.8Hz, 1H). [Explanation of Symbols]

[0355] 101 Anode 102 Cathode 103 EL layer 111 Hole injection layer 112 Hole transport layer 112-1 First hole transport layer 112-2 Second hole transport layer 113 Emitting layer 114 Electron transport layer 114-1 First electron transport layer 114-2 Second electron transport layer 115 Electron injection layer 201 Anode 202 Cathode 210 First layer 211 Second Layer 212 The third layer 400 circuit boards 401 Anode 403 EL layer 404 Cathode 405 sealant 406 Sealant 407 Sealing substrate 412 pads 420 IC chips 501 Anode 502 Cathode 511 First light-emitting unit 512 Second light-emitting unit 513 Charge generation layer 601 Drive circuit section (source line drive circuit) 602 pixel section 603 Drive circuit section (gate wire drive circuit) 604 Sealing substrate 605 Sealant 607 Space 608 Wiring 609 FPC (Flexible Printed Circuit) 610 element substrate 611 Switching FET 612 Current-Controlled FET 613 Anode 614 Insulators 616 EL layer 617 Cathode 618 Light-emitting devices 1001 circuit board 1002 Underlying insulating film 1003 Gate Insulator 10:06 Guard Station 1007 🙏 1008 Gate 1020 First interlayer insulating film 1021 Second interlayer insulating film 1022 Electrode 1024W anode 1024R Anode 1024G anode 1024B Anode 1025 Bulkhead 1028 EL layer 1029 Cathode 1031 Sealing substrate 1032 Sealant 1033 Transparent base material 1034R Red colored layer 1034G Green colored layer 1034B Blue colored layer 1035 Black Matrix 1036 Overcoat layer 1037 Third interlayer insulating film 1040 pixel section 1041 Drive circuit section 1042 Peripheral area 2001 cabinet 2002 light source 2100 Robots 2110 Arithmetic equipment 2101 Illuminance Sensor 2102 Microphone 2103 Top camera 2104 Speaker 2105 Display 2106 Lower Camera 2107 Obstacle Sensor 2108 Moving mechanism 3001 Lighting device 5000 cabinets 5001 Display section 5002 Display section 5003 Speaker 5004 LED Lamp 5006 Connection terminal 5007 Sensor 5008 Microphone 5012 Support part 5013 Earphones 5100 Cleaning Robot 5101 Display 5102 Camera 5103 Brush 5104 Operation Buttons 5150 Mobile Information Terminal 5151 enclosure 5152 Display area 5153 Bent section 5120 Garbage 5200 display area 5201 Display area 5202 Display area 5203 Display area 7101 enclosure 7103 Display section 7105 Stand 7107 Display section 7109 Operation Keys 7110 Remote Control Unit 7201 Main Unit 7202 enclosure 7203 Display section 7204 Keyboard 7205 External connection port 7206 Pointing device 7210 Second display unit 7401 enclosure 7402 Display section 7403 Operation Buttons 7404 External connection port 7405 Speaker 7406 Microphone 9310 Mobile Information Terminal 9311 Display Panel 9313 Hinge 9315 enclosure

Claims

[Claim 1] It has an anode, a cathode, and an EL layer located between the anode and the cathode. The EL layer has an emissive layer and an electron transport layer, The electron transport layer is located between the light-emitting layer and the cathode. The electron transport layer comprises an electron transport material, The electron transport material is an organic compound having a first skeleton, a second skeleton, and a third skeleton. The first skeleton described above has the function of transporting electrons, The second skeleton described above has the function of receiving holes, The third framework is a light-emitting device having a monocyclic and π-electron-deficient heteroaromatic ring.

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