Organic compounds

Abstract

To provide an organic compound with small refractive index, to provide a novel organic compound with small refractive index and electron donating property, and an EL device with high emission efficiency.SOLUTION: An organic compound having an arylamine skeleton or an acridine skeleton containing a fluorine atom, and an EL device using the organic compound are provided. The EL device preferably has a hole injection layer containing an organic compound having an arylamine skeleton or an acridine skeleton containing a fluorine atom, and a substance that exhibits electron-accepting properties for the organic compound.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] An embodiment of the present invention relates to an organic compound, an EL device, a display module, a lighting module, a display device, a light-emitting device, an electronic device, a lighting device, and an electronic device. Note that an embodiment of the present invention is not limited to the above technical field. The technical field of an embodiment of the invention disclosed in the present specification and the like relates to an object, a method, or a manufacturing method. Alternatively, an embodiment of the present invention relates to a process, a machine, a manufacture, or a composition of matter. Therefore, more specifically, examples of the technical field of an embodiment of the present invention disclosed in the present specification include a semiconductor device, a display device, a liquid crystal display device, a light-emitting device, a lighting device, a power storage device, a storage device, an imaging device, a driving method thereof, or a manufacturing method thereof. [Background technology]

[0002] Electroluminescence (EL) devices (organic EL devices) that use organic compounds are becoming more and more common. The basic structure of these EL devices is a pair of electrodes sandwiching an organic compound layer (EL layer) containing a light-emitting material between them. By applying a voltage to this element, carriers are injected, and the recombination energy of the carriers is utilized to emit light from the light-emitting material.

[0003] Since such EL devices are self-luminous, when used as display pixels, they have advantages such as high visibility and no need for backlighting compared to liquid crystals, making them suitable for use as flat panel display elements. Another major advantage of displays using such EL devices is that they can be made thin and lightweight. Another characteristic is their extremely fast response speed.

[0004] In addition, these EL devices can have a two-dimensional light-emitting layer that is continuously formed, making it possible to obtain surface light emission. This is a feature that is difficult to obtain with point light sources such as incandescent light bulbs and LEDs, or linear light sources such as fluorescent lamps, making them highly valuable as surface light sources for lighting applications.

[0005] Displays and lighting devices using such EL devices can be suitably applied to various electronic devices, and research and development is ongoing to find EL devices with better characteristics.

[0006] One of the problems that often comes up when discussing organic EL devices is their low light extraction efficiency. In particular, attenuation due to reflection caused by differences in refractive index is a major factor in reducing the efficiency of the device, and in order to reduce this effect, a structure has been proposed in which a layer made of a low refractive index material is formed inside the EL layer (for example, see Non-Patent Document 1).

[0007] Although an EL device having this structure can have a higher light-emitting efficiency than an EL device having a conventional structure, it is not easy to form a layer made of a low refractive index material inside the EL layer without adversely affecting other important properties of the EL device. This is because there is a trade-off between a low refractive index and high carrier transportability or reliability when used in an EL device. This is because the carrier transportability and reliability of organic compounds are largely derived from the presence of unsaturated bonds, and organic compounds with many unsaturated bonds tend to have a high refractive index. [Prior art documents] [Patent documents]

[0008] [Non-Patent Document 1] Jaeho Lee and 12 others, "Synergetic electrode architecture for efficient graphene-based flexible organic light-emitting diodes", Nature COMMUNICATIONS, June 2, 2016, DOI:10.1038 / ncomms11791 Summary of the Invention [Problem to be solved by the invention]

[0009] An object of one embodiment of the present invention is to provide a novel organic compound. Alternatively, an object of one embodiment of the present invention is to provide an organic compound having a small refractive index. Alternatively, an object of one embodiment of the present invention is to provide a novel organic compound having a small refractive index and high electron donating property.

[0010] Another object of the present invention is to provide an EL device with high luminous efficiency, or an EL device, a light-emitting device, an electronic device, a display device, and an electronic device with low power consumption.

[0011] Note that the description of these effects does not preclude the existence of other effects. Note that one embodiment of the present invention does not necessarily have all of these effects. Note that effects other than these will become apparent from the description in the specification, drawings, claims, etc., and it is possible to extract effects other than these from the description in the specification, drawings, claims, etc.

[0012] It is sufficient for the present invention to solve any one of the above problems. [Means for solving the problem]

[0013] One embodiment of the present invention is an EL device having an anode, a cathode, and an EL layer located between the anode and the cathode, the EL layer having a first layer containing a first substance and a second substance, the first substance being a substance that exhibits electron donating properties toward the second substance, the first substance having an arylamine skeleton or an acridine skeleton, and the first substance containing a fluorine atom.

[0014] Alternatively, another embodiment of the present invention is an EL device comprising an anode, a cathode, and an EL layer located between the anode and the cathode, the EL layer comprising a first layer containing a first substance and a second substance, the first substance being a substance exhibiting electron donating properties toward the second substance, the first substance having an arylamine skeleton or an acridine skeleton, the first substance having one or more aromatic rings with which the lone electron pair of a nitrogen atom of the arylamine skeleton or the acridine skeleton can be conjugated, and one or two of the aromatic rings having fluorine atoms bonded thereto.

[0015] Another embodiment of the present invention is an EL device having the above structure, in which a fluorine atom is bonded to one of the aromatic rings.

[0016] Another embodiment of the present invention is an EL device having the above structure, in which the first substance has a refractive index of 1.8 or less.

[0017] Alternatively, another aspect of the present invention is an EL device having the above-mentioned structure, wherein the EL layer includes a hole injection layer and a light-emitting layer, the light-emitting layer is provided between the hole injection layer and the cathode, the hole injection layer is provided in contact with the anode, and the first layer is the hole injection layer.

[0018] Alternatively, another embodiment of the present invention is an EL device having the above-mentioned structure, wherein the EL layer has a plurality of light-emitting units and a charge generation layer provided between the plurality of light-emitting units, and the first layer is the charge generation layer.

[0019] Alternatively, another embodiment of the present invention is an EL device having the above-mentioned structure, in which the EL layer further includes a second layer, the second layer includes a third substance and a fourth substance, the third substance is a substance that exhibits electron donating properties toward the fourth substance, the third substance is an organic compound having an arylamine skeleton or an acridine skeleton, and the third substance contains a fluorine atom.

[0020] Alternatively, another embodiment of the present invention is an EL device having the above-mentioned structure, wherein the EL layer further includes a second layer, the second layer including a third substance and a fourth substance, the third substance being a substance exhibiting electron donating properties toward the fourth substance, the third substance being an organic compound having an arylamine skeleton or an acridine skeleton, and the first substance having one or more aromatic rings with which the lone electron pair of a nitrogen atom in the arylamine skeleton or the acridine skeleton can be conjugated, and a fluorine atom is bonded to one or two of the aromatic rings.

[0021] Another embodiment of the present invention is an EL device having the above structure, in which the third substance has a refractive index of 1.8 or less.

[0022] Alternatively, another embodiment of the present invention is an EL device, in which the light-emitting unit closest to the anode among the plurality of light-emitting units has a hole-injection layer in contact with the anode, and the second layer is the hole-injection layer.

[0023] Alternatively, another embodiment of the present invention is an EL device having the above structure, in which the first substance and the third substance are the same substance, and the second substance and the fourth substance are the same substance.

[0024] Another embodiment of the present invention is an EL device having the above structure, in which the organic compound contains five or more fluorine atoms.

[0025] Another embodiment of the present invention is an EL device having the above structure, in which the organic compound contains 7 atomic % or more and 40 atomic % or less of fluorine atoms.

[0026] Another embodiment of the present invention is an EL device having the above structure, in which the aromatic ring to which the fluorine atom is bonded is a benzene ring or a naphthalene ring.

[0027] Alternatively, another embodiment of the present invention is an EL device having the above structure, in which the aromatic ring to which the fluorine atom is bonded is a perfluoroaryl group.

[0028] Alternatively, another embodiment of the present invention is an EL device having the above structure, in which the aromatic ring to which the fluorine atom is bonded is a perfluorophenyl group or a perfluorobiphenyl group.

[0029] Another embodiment of the present invention is an EL device having the above structure, wherein the hole injection layer has a thickness of 20 nm or more.

[0030] Another embodiment of the present invention is an EL device having the above structure, in which the second substance is molybdenum oxide.

[0031] Another embodiment of the present invention is an organic compound represented by the following general formula (G1).

[0032] [ka]

[0033] In the above general formula (G1), R 1 ~R 4 and R 7 ~R 10 are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, and a fluorinated alkyl group having 1 to 6 carbon atoms; R 5 and R 6are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, a fluorinated alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted phenyl group. 13 is either fluorine or a group represented by the following general formula (g1):

[0034] [ka]

[0035] In the above general formula (g1), R 21 ~R 24 and R 27 ~R 30 are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, and a fluorinated alkyl group having 1 to 6 carbon atoms; R 25 and R 26 each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a fluorinated alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted phenyl group.

[0036] Alternatively, another embodiment of the present invention is a method for manufacturing a semiconductor device comprising the steps of: 13 is an organic compound represented by the general formula (g1).

[0037] Another embodiment of the present invention is an organic compound represented by the following general formula (G2).

[0038] [ka]

[0039] In the above general formula (G2), R 1 ~R 4 and R 7 ~R 10 are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, and a fluorinated alkyl group having 1 to 6 carbon atoms; R 5 and R 6are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, a fluorinated alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted phenyl group. 33 is either fluorine or a group represented by the following general formula (g1):

[0040] [ka]

[0041] In the above general formula (g1), R 21 ~R 24 and R 27 ~R 30 are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, and a fluorinated alkyl group having 1 to 6 carbon atoms; R 25 and R 26 each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a fluorinated alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted phenyl group.

[0042] Alternatively, another embodiment of the present invention is a method for manufacturing a semiconductor device comprising the steps of: 33 is an organic compound represented by the general formula (g1).

[0043] Alternatively, another embodiment of the present invention is a method for manufacturing a semiconductor device comprising the steps of: 25 and R 26 is an organic compound in which the phenyl group is

[0044] Alternatively, another embodiment of the present invention is a method for manufacturing a semiconductor device comprising the steps of: 21 ~R 24 and R 27 ~R 30 is an organic compound in which

[0045] Alternatively, another embodiment of the present invention is a method for manufacturing a semiconductor device comprising the steps of: 5 and R 6 is an organic compound in which the phenyl group is

[0046] Another embodiment of the present invention is an organic compound having the above structure and represented by the following structural formula (100):

[0047] [ka]

[0048] Another embodiment of the present invention is an organic compound represented by the following structural formula (200) in the above structure.

[0049] [ka]

[0050] Another embodiment of the present invention is an EL device including any one of the organic compounds described above.

[0051] Another embodiment of the present invention is an EL device including any one of the organic compounds described above as a hole transport material.

[0052] Another embodiment of the present invention is an EL device including any one of the above organic compounds in a hole-injection layer.

[0053] Alternatively, another embodiment of the present invention is an EL device having an anode, a cathode, and an EL layer provided between the anode and the cathode, the EL layer including a hole injection layer and a light-emitting layer, the light-emitting layer being located between the hole injection layer and the cathode, the hole injection layer being provided in contact with the anode, the hole injection layer including any one of the organic compounds described above and a second substance, and the organic compound being a substance that exhibits electron-donating properties to the second substance.

[0054] Another embodiment of the present invention is an EL device having the above structure, in which the organic compound has a refractive index of 1.8 or less.

[0055] Another embodiment of the present invention is an EL device having the above structure, wherein the hole injection layer has a thickness of 20 nm or more.

[0056] Another embodiment of the present invention is an EL device having the above structure, in which the second substance is molybdenum oxide.

[0057] Another embodiment of the present invention is a light-emitting device including any one of the above EL devices and a transistor or a substrate.

[0058] Another embodiment of the present invention is an electronic device including the above-described light-emitting device and a sensor, an operation button, a speaker, or a microphone.

[0059] Another embodiment of the present invention is a lighting device including the above-described light-emitting device and a housing.

[0060] Another embodiment of the present invention is an electronic device including any of the organic compounds described above.

[0061] In this specification, the term "light-emitting device" includes an image display device using an EL device. A module in which a connector, such as an anisotropic conductive film or TCP (Tape Carrier Package), is attached to an EL device, a module in which a printed wiring board is provided at the tip of a TCP, or a module in which an IC (integrated circuit) is directly mounted on an EL device by a COG (Chip On Glass) method may have a light-emitting device. Furthermore, lighting fixtures and the like may have a light-emitting device. Effect of the Invention

[0062] According to one embodiment of the present invention, a novel organic compound can be provided. Alternatively, according to one embodiment of the present invention, an organic compound having a small refractive index can be provided. Alternatively, according to one embodiment of the present invention, an organic compound having a small refractive index and high electron donating property can be provided.

[0063] According to another embodiment of the present invention, an EL device with high emission efficiency can be provided. According to another embodiment of the present invention, an EL device, a light-emitting device, an electronic device, a display device, and an electronic device with low power consumption can be provided.

[0064] Note that the description of these effects does not preclude the existence of other effects. Note that one embodiment of the present invention does not necessarily have all of these effects. Note that effects other than these will become apparent from the description in the specification, drawings, claims, etc., and it is possible to extract effects other than these from the description in the specification, drawings, claims, etc. [Brief description of the drawings]

[0065] [Figure 1] 1A to 1C are schematic diagrams of an EL device. [Diagram 2] 2A and 2B are conceptual diagrams of an active matrix type light emitting device. [Diagram 3] 3A and 3B are conceptual diagrams of an active matrix type light emitting device. [Figure 4] FIG. 4 is a conceptual diagram of an active matrix type light emitting device. [Diagram 5] 5A and 5B are conceptual diagrams of a passive matrix type light emitting device. [Figure 6] 6A and 6B are diagrams illustrating a lighting device. [Figure 7] 7A, 7B1, 7B2 and 7C are diagrams illustrating electronic equipment. [Figure 8] 8A to 8C are diagrams illustrating an electronic device. [Figure 9] FIG. 9 is a diagram illustrating a lighting device. [Figure 10] FIG. 10 is a diagram illustrating a lighting device. [Figure 11] FIG. 11 is a diagram illustrating an in-vehicle display device and a lighting device. [Figure 12] 12A and 12B are diagrams illustrating an electronic device. [Figure 13] 13A to 13C are diagrams illustrating an electronic device. [Figure 14] 14A and 14B are 1H NMR charts of F9BPPad. [Figure 15] 15A and 15B are 19F-NMR charts of F9BPPad. [Figure 16] Figures 16A and 16B are 1H NMR charts of Pad2F8BP. [Figure 17] Figures 17A and 17B are 19F-NMR charts of Pad2F8BP. [Figure 18] FIG. 18 is a graph showing the refractive index of composite materials using F9BPPad, Pad2F8BP, DBT3P-II, and FATPA. [Figure 19] FIG. 19 shows the absorption spectrum and emission spectrum of F9BPPad in a toluene solution. [Figure 20] FIG. 20 shows the absorption spectrum and emission spectrum of Pad2F8BP in a toluene solution. [Figure 21] FIG. 21 shows the luminance vs. current density characteristics of EL Device 1-0, EL Device 2-0, Comparative EL Device 1-0, and Comparative EL Device 2-0. [Figure 22] FIG. 22 shows the current efficiency-luminance characteristics of EL device 1-0, EL device 2-0, comparative EL device 1-0, and comparative EL device 2-0. [Figure 23] FIG. 23 shows the luminance-voltage characteristics of EL Device 1-0, EL Device 2-0, Comparative EL Device 1-0, and Comparative EL Device 2-0. [Figure 24] FIG. 24 shows the current-voltage characteristics of EL Device 1-0, EL Device 2-0, Comparative EL Device 1-0, and Comparative EL Device 2-0. [Diagram 25] FIG. 25 shows the external quantum efficiency-luminance characteristics of EL device 1-0, EL device 2-0, comparative EL device 1-0, and comparative EL device 2-0. [Figure 26]FIG. 26 shows the emission spectra of EL Device 1-0, EL Device 2-0, Comparative EL Device 1-0, and Comparative EL Device 2-0. [Figure 27] FIG. 27 shows the relationship between chromaticity x and external quantum efficiency in the vicinity of 1000 cd / m 2 for the EL device of the example and the EL device of the comparative example. [Figure 28] FIG. 28 shows normalized luminance vs. time change characteristics of the EL device of the embodiment and the EL device of the comparative example. [Figure 29] FIG. 29 is the MS spectrum of F9BPPad. [Diagram 30] Figure 30 is the MS spectrum of Pad2F8BP. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

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

[0067] (Embodiment 1) An organic EL device (hereinafter also referred to as an EL device) usually has a structure in which a layer containing an organic compound (also referred to as an EL layer), which is composed of multiple layers with separate functions such as a light-emitting layer, a carrier transport layer, a carrier injection layer, etc., is sandwiched between a pair of electrodes. A hole injection layer and a hole transport layer are formed between the anode and the light-emitting layer, and play the role of smoothly injecting holes from the electrode to the EL layer and quickly transporting and injecting holes to the light-emitting layer.

[0068] As reported in Non-Patent Document 1, the luminous efficiency of an organic EL device can be improved by providing an internal layer with a lower refractive index than the surrounding materials. As the name suggests, an organic EL device is an EL device that uses an EL layer containing an organic compound, and the refractive index of the organic compound is highly dependent on the atomic refraction of the atoms that make up the organic compound. In other words, an organic compound that has a high ratio of atoms with small atomic refraction among the atoms that make up the organic compound is likely to have a small refractive index, and an organic EL device made using the organic compound can be an EL device with high luminous efficiency.

[0069] Here, fluorine atoms are a representative example of atoms with small atomic refraction. However, because fluorine atoms have a high electron-withdrawing property, organic compounds containing many fluorine atoms are predicted to have a detrimental effect on hole transport properties and electron donating properties, and therefore have rarely been used as hole transport materials or electron donating materials.

[0070] However, the present inventors have found that an organic compound having an arylamine skeleton or an acridine skeleton can be suitably used as an electron donating material even if it contains a fluorine atom in its molecular structure. The organic compound containing fluorine, which has a low atomic refraction, can be made into an organic compound with a low refractive index, and a hole injection layer made using the organic compound can be made into a layer with a small refractive index, making it possible to provide an EL device with high luminous efficiency.

[0071] In organic compounds having an arylamine skeleton or an acridine skeleton, the lone electron pair in the nitrogen of the skeleton contributes to electron donating property, and it was thought that when fluorine is substituted on an aromatic ring in a range where the lone electron pair can be conjugated, the electron withdrawing property is greatly affected, and the electron donating property of the organic compound is further reduced. However, the inventors have found that an organic compound having an arylamine skeleton or an acridine skeleton does not lose its electron donating property significantly even when fluorine is substituted on such an aromatic ring, and can function as an electron donating material when used together with an electron accepting material, and can be suitably used as a hole injection layer of an EL device. This makes it easy to use an organic compound containing more fluorine atoms in the molecule as an electron donating material, and a layer with a lower refractive index can be formed inside the light emitting layer. As a result, it is possible to provide an EL device with better luminous efficiency.

[0072] In the organic compound in which hydrogen in an aromatic ring present within a range in which a lone electron pair in a nitrogen of the arylamine skeleton or acridine skeleton can be conjugated is substituted with fluorine, when multiple aromatic rings are bonded to the nitrogen, it is preferable that a fluorine atom is bonded to one or two aromatic rings rather than a configuration in which fluorine atoms are bonded to all aromatic rings.

[0073] In addition, since the refractive index can be reduced as the proportion of fluorine atoms contained in the organic compound increases, it is preferable that four or more fluorine atoms are bonded to the aromatic ring, and it is even more preferable that fluorine atoms are bonded to all substitutable positions.

[0074] The aromatic ring is preferably a benzene ring or a naphthalene ring, and more preferably a benzene ring.

[0075] In the organic compound, it is preferable that the number of aromatic rings having a fluorine atom within a range in which the lone electron pair on the nitrogen of the arylamine skeleton or acridine skeleton can be conjugated is one, since the electron donating property is not too low.

[0076] In addition, a substituent having a fluorine atom may be bonded to the organic compound outside the range where the lone electron pair in the nitrogen of the arylamine skeleton or acridine skeleton can be conjugated. Examples of the substituent having a fluorine atom include fluorinated alkyl groups and fluorinated aryl groups, and fluorinated aryl groups are more preferable. Among them, an aryl group having 5 or more fluorine atoms, particularly a perfluoroaryl group, is preferable because it has a large number of fluorine atoms and can obtain an organic compound with a lower refractive index. In addition, an organic compound having a fluorine atom in an aromatic ring where the lone electron pair in the nitrogen of the arylamine skeleton or acridine skeleton can be conjugated and also having a fluorine atom outside the range is more preferable because the ratio of fluorine atoms in the molecule is high and the refractive index can be further reduced.

[0077] Another major feature of EL devices using the above organic compounds as electron donating materials is that they have improved luminous efficiency while also maintaining good major characteristics other than luminous efficiency (driving voltage, lifetime, etc.) similar to those of EL devices using organic compounds that do not contain fluorine atoms.

[0078] That is, the present inventors have found an organic compound with a low refractive index that contains many fluorine atoms with high electron-withdrawing properties while maintaining good electron-donating properties, and have realized an EL device with good luminous efficiency using the organic compound. In particular, when the organic compound is used as a first substance and a substance that exhibits electron-donating properties as the second substance, an EL device using a layer containing the first substance and the second substance as a hole injection layer or an intermediate layer (charge generation layer) in a tandem element can be an EL device that not only has improved luminous efficiency, but also has good main characteristics other than luminous efficiency (driving voltage, life, etc.).

[0079] If the ratio of fluorine atoms in the molecule of the organic compound (first substance) exceeds 40 atomic %, the electron donating property becomes too low and the function as a donor material decreases, so the ratio of fluorine atoms is preferably 40 atomic % or less. In order to achieve a low refractive index, it is preferable that the fluorine atoms are contained at 7 atomic % or more.

[0080] Some of the preferred embodiments of the organic compounds (first substances) described above can be expressed as specific examples by the following general formulas.

[0081] [ka]

[0082] In the above general formula (G1), R 1 ~R 4 and R 7 ~R 10 are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, and a fluorinated alkyl group having 1 to 6 carbon atoms; R 5 and R 6 are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, a fluorinated alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted phenyl group. 13 is either fluorine or a group represented by the following general formula (g1):

[0083] [ka]

[0084] In the above general formula (g1), R 21 ~R 24 and R 27 ~R 30 are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, and a fluorinated alkyl group having 1 to 6 carbon atoms; R 25 and R 26each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a fluorinated alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted phenyl group.

[0085] In the organic compound represented by the general formula (G1), R 13 is preferably fluorine since this results in an organic compound with a lower refractive index, and is preferably a group represented by the above general formula (g1) since it imparts stronger electron donating properties.

[0086] The organic compound of one embodiment of the present invention can also be represented by the following general formula (G2).

[0087] [ka]

[0088] In the above general formula (G2), R 1 ~R 4 and R 7 ~R 10 are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, and a fluorinated alkyl group having 1 to 6 carbon atoms; R 5 and R 6 are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, a fluorinated alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted phenyl group. 33 is either fluorine or a group represented by the above general formula (g1).

[0089] [ka]

[0090] In the above general formula (G3), R 1 ~R 4 and R 7 ~R 10 are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, and a fluorinated alkyl group having 1 to 6 carbon atoms; R 5 and R6 are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, a fluorinated alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted phenyl group. 21 ~R 24 and R 27 ~R 30 are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, and a fluorinated alkyl group having 1 to 6 carbon atoms; R 25 and R 26 each independently represents any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, a fluorinated alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted phenyl group.

[0091] In the organic compound represented by the general formula (G2), R 33 is preferably fluorine, since this will result in an organic compound with a lower refractive index. That is, a preferred embodiment of the present invention is an organic compound represented by the following general formula (G4).

[0092] [ka]

[0093] In the above general formula (G4), R 1 ~R 4 and R 7 ~R 10 are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, and a fluorinated alkyl group having 1 to 6 carbon atoms; R 5 and R 6 each independently represents any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, a fluorinated alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted phenyl group.

[0094] In addition, in the organic compound represented by the above general formula (G2), R 33 is preferably an organic compound represented by the above general formula (g1) because it imparts stronger electron donating properties. That is, a preferred embodiment of the present invention is an organic compound represented by the above general formula (G3).

[0095] In the organic compounds represented by the general formulas (G1) to (G4), R 5 and R 6 is preferably a substituted or unsubstituted phenyl group, particularly an unsubstituted phenyl group, in order to improve the glass transition temperature (Tg) and maintain the heat resistance of the EL device. 25 or R 26 is preferably a substituted or unsubstituted phenyl group, particularly preferably an unsubstituted phenyl group, for the same reasons.

[0096] In the organic compounds represented by the general formulas (G1) to (G4), R 2 and R 9 In order to maintain a low refractive index, it is preferable that R is hydrogen. 22 or R 29 is preferably hydrogen for the same reason.

[0097] In the organic compounds represented by the general formulas (G1) to (G4), R 1 ~R 4 and R 7 ~R 10 In order to maintain a low refractive index, it is preferable that R is hydrogen. 21 ~R 24 and R 27 ~R 30 is preferably hydrogen for the same reason.

[0098] In the organic compounds represented by the above general formulae (G1) to (G4), specific examples of the alkyl group having 1 to 6 carbon atoms and the fluorinated alkyl group having 1 to 6 carbon atoms include groups represented by the following formulae (1-1) to (1-23). ​​When the above substituted or unsubstituted phenyl group has a substituent, the substituent may be a fluoro group, a phenyl group, a dibenzothiophenyl group, a carbazolyl group, a fluorenyl group, a dimethylfluorenyl group, a diphenyltriazinyl group, or the like, in addition to the groups represented by the following formulae (1-1) to (1-23).

[0099] [ka]

[0100] Specific examples of organic compounds having the above structure are shown below.

[0101] [ka]

[0102] [ka]

[0103] [ka]

[0104] [ka]

[0105] [ka]

[0106] [ka]

[0107] [ka]

[0108] [ka]

[0109] [ka]

[0110] Next, an example of a method for synthesizing the organic compound represented by the above general formula (G1) or (G2) will be described.

[0111] The organic compound represented by the above general formula (G1) or general formula (G2) can be synthesized by reacting a 9,10-dihydroacridine derivative (g1-1) with a fluorinated benzene derivative (m1) or a fluorinated biphenyl derivative (m2) in the presence of a strong base, as shown in the synthesis scheme below.

[0112] [ka]

[0113] [ka]

[0114] In the above synthesis scheme, R 1 ~R 4 and R 7 ~R 10 are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, and a fluorinated alkyl group having 1 to 6 carbon atoms; R 5 and R 6 are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, a fluorinated alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted phenyl group. 4 or X16 is fluorine or chlorine, R 13 or R 33 is fluorine or a group represented by the following general formula (g1).

[0115] [ka]

[0116] In the above general formula (g1), R 21 ~R 24 and R 27 ~R 30 are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, and a fluorinated alkyl group having 1 to 6 carbon atoms; R 25 and R 26 each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a fluorinated alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted phenyl group.

[0117] When the above synthesis scheme is carried out by an aromatic electrophilic substitution reaction, examples of the base include inorganic bases such as lithium amide, sodium amide, sodium hydroxide, potassium hydroxide, etc., and organic bases such as sodium tert-butoxide, etc. When a solvent is used in the reaction, tetrahydrofuran, 1,4-dioxane, dimethoxyethane, formamide, dimethylformamide, dimethylsulfoxide, etc. can be used.

[0118] The organic compound represented by the above general formula (G1) or general formula (G2) can also be synthesized by reacting a 9,10-dihydroacridine derivative (g1-1) with a fluorinated benzene derivative (m3) or a fluorinated biphenyl derivative (m4) in the presence of a palladium catalyst and a base, as shown in the synthesis scheme below.

[0119] [ka]

[0120] [ka]

[0121] In the above synthesis scheme, R 1 ~R 4 and R 7 ~R 10 are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, and a fluorinated alkyl group having 1 to 6 carbon atoms; R 5 and R 6 are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, a fluorinated alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted phenyl group. 4 or X 16 represents a halogen or a triflate group. The halogen is preferably iodine, bromine, or chlorine. 13 or R 33 is fluorine or a group represented by the following general formula (g1).

[0122] [ka]

[0123] In the above general formula (g1), R 21 ~R 24 and R 27 ~R 30 are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, and a fluorinated alkyl group having 1 to 6 carbon atoms; R 25 and R 26 each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a fluorinated alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted phenyl group.

[0124] In the above synthesis scheme, X 4 or X 16 represents a halogen or a triflate group. As the halogen, iodine, bromine or chlorine is preferred.

[0125] The above synthesis scheme may be carried out as a Buchwald-Hartwig reaction. In this reaction, a palladium catalyst is used that uses a palladium complex or compound such as bis(dibenzylideneacetone)palladium(0) or allylpalladium chloride dimer(II) and a ligand such as tri(tert-butyl)phosphine, di-tert-butyl(1-methyl-2,2-diphenylcyclopropyl)phosphine, or tricyclohexylphosphine. Examples of the base include organic bases such as sodium tert-butoxide and inorganic bases such as potassium carbonate. In addition, when a solvent is used in this reaction, toluene, xylene, 1,3,5-trimethylbenzene, etc. can be used.

[0126] As described above, the organic compound represented by the general formula (G1) or (G2) can be synthesized.

[0127] Here, as described above, an organic compound (first substance) having the above-mentioned arylamine skeleton or acridine skeleton, typically represented by general formula (G1) or general formula (G2), and containing fluorine can be suitably used as a hole injection layer or intermediate layer in an EL device by using the organic compound together with a second substance capable of exhibiting electron donating properties. The first substance and the second substance may be used in a mixed state or may be laminated as thin films of each substance, but it is preferable to use a composite material mixed by co-evaporation.

[0128] In a pair of substances, if one substance exhibits electron donating properties to the other substance, the other substance can be said to exhibit electron accepting properties to the first substance. Therefore, the second substance can be said to have electron accepting properties toward the first substance. Examples of substances having electron accepting properties that can be used as the second substance include molybdenum oxide, vanadium oxide, ruthenium oxide, tungsten oxide, manganese oxide, and the like. Among these, molybdenum oxide is particularly preferred because it is stable in the air, has low hygroscopicity, and is easy to handle.

[0129] In addition to the above-mentioned substances, organic compounds having an electron-withdrawing group (halogen group or cyano group) can be used as electron-accepting substances. Radialene derivatives [3] having an electron-withdrawing group (especially a halogen group such as a fluoro group or a cyano group) have very high electron-accepting properties and can be suitably used as organic compounds having electron-accepting properties. Examples of such organic compounds include 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (abbreviation: F4-TCNQ), 3,6-difluoro-2,5,7,7,8,8-hexacyanoquinodimethane, chloranil, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene (abbreviation: HAT-CN), 1,3,4,5,7,8-hexafluorotetracyano-naphthoquinodimethane (abbreviation: F6-TCNNQ), etc. or α,α',α''-1,2,3-cyclopropane triylidene tris[4-cyano-2,3,5,6-tetrafluorobenzeneacetonitrile], α,α',α''-1,2,3-cyclopropane triylidene tris[2,6-dichloro-3,5-difluoro-4-(trifluoromethyl)benzeneacetonitrile], or α,α',α''-1,2,3-cyclopropane triylidene tris[2,3,4,5,6-pentafluorobenzeneacetonitrile]. As an organic compound having electron accepting properties, a compound in which an electron withdrawing group is bonded to a condensed aromatic ring having a plurality of heteroatoms, such as HAT-CN, is thermally stable and is preferable.

[0130] In addition, phthalocyanine (abbreviation: H 2 Also usable are phthalocyanine complex compounds such as copper(II) phthalocyanine (CuPC) and copper(II) phthalocyanine (CuPC); and aromatic amine compounds such as 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB) and N,N'-bis{4-[bis(3-methylphenyl)amino]phenyl}-N,N'-diphenyl-(1,1'-biphenyl)-4,4'-diamine (abbreviation: DNTPD).

[0131] In addition, by using a composite material obtained by co-evaporating an electron donor material and an electron acceptor material to be mixed as a hole injection layer in contact with an anode, it is possible to select a material for forming an electrode regardless of its work function. In other words, not only a material with a large work function but also a material with a small work function can be used as an anode.

[0132] (Embodiment 2) In this embodiment, a detailed embodiment of the EL device described in Embodiment 1 will be described. FIG. 1 illustrates an EL device according to one embodiment of the present invention. The EL device illustrated in FIG. 1A includes an anode 101, a cathode 102, and an EL layer 103. The EL device according to one embodiment of the present invention includes an organic compound (first substance) having the arylamine skeleton or acridine skeleton described in Embodiment 1 and containing fluorine in the EL layer 103. The first substance preferably forms a first layer together with a second substance in the EL layer 103. Note that the first substance exhibits electron donating properties to the second substance.

[0133] In FIG. 1, the first layer is preferably used as a hole-injection layer 111. The EL layer 103 has various functional layers including a light-emitting layer 113 in addition to the first layer, and may have a hole-transport layer 112, an electron-transport layer 114, an electron-injection layer 115, and the like in addition to the light-emitting layer 113 and the hole-injection layer 111. The light-emitting layer 113 contains a light-emitting material, and the EL device of one embodiment of the present invention obtains light emission from the light-emitting material. The light-emitting layer 113 may contain a host material or other materials. The first substance may be contained in the light-emitting layer 113, the hole-transport layer 112, or the hole-injection layer, or may be contained in any of them. Note that the configuration of the EL device is not limited to these.

[0134] Since the first substance is an organic compound with a low refractive index, by using it inside the EL layer, an EL device with good external quantum efficiency can be obtained. In addition, the first layer containing the first substance and the second substance can also be a layer with a low refractive index, and similarly, an EL device having the first layer can be an EL device with good external quantum efficiency. In addition, the first layer functions favorably as a hole injection layer, and an EL device in which the first layer is a hole injection layer can be an EL device with high luminous efficiency such as external quantum efficiency and also with good main performance other than luminous efficiency (driving voltage, life, etc.).

[0135] Next, examples of the detailed structure and materials of the above-mentioned EL device will be described.

[0136] The anode 101 is preferably formed using a metal, alloy, conductive compound, or mixture thereof having a large work function (specifically, 4.0 eV or more). Specific examples include indium oxide-tin oxide (ITO), indium oxide-tin oxide containing silicon or silicon oxide, indium oxide-zinc oxide, and indium oxide containing tungsten oxide and zinc oxide (IWZO). These conductive metal oxide films are usually formed by a sputtering method, but may be formed by applying a sol-gel method or the like. As an example of a method for forming the indium oxide-zinc oxide, there is a method for forming the indium oxide-zinc oxide by a sputtering method using a target containing 1 to 20 wt % zinc oxide added to indium oxide. In addition, indium oxide containing tungsten oxide and zinc oxide (IWZO) can also be formed by a sputtering method using a target containing 0.5 to 5 wt % tungsten oxide and 0.1 to 1 wt % zinc oxide relative to indium oxide. Other examples include gold (Au), platinum (Pt), nickel (Ni), tungsten (W), chromium (Cr), molybdenum (Mo), iron (Fe), cobalt (Co), copper (Cu), palladium (Pd), and nitrides of metal materials (e.g., titanium nitride). Graphene can also be used. By using a composite material described later in the layer in contact with the anode 101 in the EL layer 103, it becomes possible to select an electrode material regardless of the work function.

[0137] The EL layer 103 preferably has a laminated structure, but the laminated structure is not particularly limited, and various layer structures such as a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a carrier block layer, an exciton block layer, and a charge generation layer can be applied. In this embodiment, two types of structures will be described: a structure having an electron transport layer 114 and an electron injection layer 115 in addition to a hole injection layer 111, a hole transport layer 112, and a light-emitting layer 113 as shown in FIG. 1A, and a structure having an electron transport layer 114, an electron injection layer 115, and a charge generation layer 116 in addition to a hole injection layer 111, a hole transport layer 112, and a light-emitting layer 113 as shown in FIG. 1B. The materials constituting each layer are specifically described below.

[0138] The EL device according to one embodiment of the present invention includes a first layer having a low refractive index as described in Embodiment 1, and the first layer is preferably a hole-injection layer 111 .

[0139] In the case where the hole injection layer 111 is not the first layer, it can be formed using a substance having an electron accepting property. As the substance having an electron accepting property, in addition to the substances given as the substances that can be used as the second substance in the embodiment mode 1, polymers such as poly(3,4-ethylenedioxythiophene) / poly(styrenesulfonic acid) (PEDOT / PSS) can also be used. The substance having an electron accepting property can extract electrons from an adjacent hole transport layer (or hole transport material) by application of an electric field, and can inject (generate) holes into the adjacent hole transport layer (or hole transport material) by extracting the electrons.

[0140] Furthermore, a composite material in which a substance having a hole-transporting property contains an electron-accepting substance can also be used as the hole-injection layer 111. Note that by using a composite material in which a substance having a hole-transporting property contains an electron-accepting substance, a material for forming an electrode can be selected regardless of the work function. That is, not only a material with a high work function but also a material with a low work function can be used as the anode 101. As the electron-accepting substance, any of the substances listed in Embodiment 1 that can be used as the second substance can be used.

[0141] As the hole transporting substance used in the composite material, various organic compounds such as aromatic amine compounds, carbazole derivatives, aromatic hydrocarbons, and polymer compounds (oligomers, dendrimers, polymers, etc.) can be used. -6 cm 2 It is preferable that the material has a hole mobility of 1 / Vs or more. Specific examples of organic compounds that can be used as the hole-transporting material in the composite material are listed below.

[0142] Examples of aromatic amine compounds that can be used in the composite material include N,N'-di(p-tolyl)-N,N'-diphenyl-p-phenylenediamine (abbreviation: DTDPPA), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviation: DPAB), N,N'-bis{4-[bis(3-methylphenyl)amino]phenyl}-N,N'-diphenyl-(1,1'-biphenyl)-4,4'-diamine (abbreviation: DNTPD), 1,3,5-tris[N-(4-diphenylaminophenyl)-N-phenylamino]benzene (abbreviation: DPA3B), and 1,1-bis-(4-bis(4-methyl-phenyl)-amino-phenyl)-cyclohexane (abbreviation: TAPC). Specific examples of the carbazole derivative include 3-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3,6-bis[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA2), 3-[N-(1-naphthyl)-N-(9-phenylcarbazol-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCA3), Examples of compounds that can be used include tris[4-(N-carbazolyl)phenyl]benzene (abbreviation: TCPB), 9-[4-(N-carbazolyl)]phenyl-10-phenylanthracene (abbreviation: CzPA), and 1,4-bis[4-(N-carbazolyl)phenyl]-2,3,5,6-tetraphenylbenzene.Examples of aromatic hydrocarbons include 2-tert-butyl-9,10-di(2-naphthyl)anthracene (abbreviation: t-BuDNA), 2-tert-butyl-9,10-di(1-naphthyl)anthracene, 9,10-bis(3,5-diphenylphenyl)anthracene (abbreviation: DPPA), 2-tert-butyl-9,10-bis(4-phenylphenyl)anthracene (abbreviation: t-BuDBA), 9,10-di(2-naphthyl)anthracene (abbreviation: DNA), 9,10-diphenylanthracene (abbreviation: DPAnth), 2-tert-butylanthracene (abbreviation: t-BuAnth), 9,10-bis(4-methyl-1-naphthyl)anthracene (abbreviation: DMNA), 2-tert- Butyl-9,10-bis[2-(1-naphthyl)phenyl]anthracene, 9,10-bis[2-(1-naphthyl)phenyl]anthracene, 2,3,6,7-tetramethyl-9,10-di(1-naphthyl)anthracene, 2,3,6,7-tetramethyl-9,10-di(2-naphthyl)anthracene, 9,9'-bianthryl, 10,10'-diphenyl-9,9'-bianthryl, 10,10'-bis(2-phenylphenyl)-9,9'-bianthryl, 10,10'-bis[(2,3,4,5,6-pentaphenyl)phenyl]-9,9'-bianthryl, anthracene, tetracene, rubrene, perylene, 2,5,8,11-tetra(tert-butyl)perylene, etc. In addition, pentacene, coronene, etc. can also be used. It may have a vinyl skeleton. Examples of aromatic hydrocarbons having a vinyl group include 4,4'-bis(2,2-diphenylvinyl)biphenyl (abbreviation: DPVBi) and 9,10-bis[4-(2,2-diphenylvinyl)phenyl]anthracene (abbreviation: DPVPA).

[0143] In addition, polymer compounds such as poly(N-vinylcarbazole) (abbreviation: PVK), poly(4-vinyltriphenylamine) (abbreviation: PVTPA), poly[N-(4-{N'-[4-(4-diphenylamino)phenyl]phenyl-N'-phenylamino}phenyl)methacrylamide] (abbreviation: PTPDMA), and poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)benzidine] (abbreviation: Poly-TPD) can also be used.

[0144] The hole transport layer 112 is formed by including a material having a hole transport property. -6 cm 2 It is preferable that the hole mobility is 1 / Vs or more.

[0145] Examples of the material having the hole transport property include 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB), N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (abbreviation: TPD), 4,4'-bis[N-(spiro-9,9'-bifluoren-2-yl)-N-phenylamino]biphenyl (abbreviation: BSPB), 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: B PAFLP), 4-phenyl-3'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: mBPAFLP), 4-phenyl-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBA1BP), 4,4'-diphenyl-4''-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBBi1BP), 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: Aromatic amines such as PCBANB), 4,4'-di(1-naphthyl)-4''-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBNBB), 9,9-dimethyl-N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]fluoren-2-amine (abbreviation: PCBAF), and N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]spiro-9,9'-bifluoren-2-amine (abbreviation: PCBASF). Compounds with a carbazole skeleton, such as 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), and 3,3'-bis(9-phenyl-9H-carbazole) (abbreviation: PCCP), and compounds with a carbazole skeleton, such as 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzothiophene) (abbreviation: DBT3P-II), 2,Examples of the compounds include compounds having a thiophene skeleton such as 8-diphenyl-4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]dibenzothiophene (abbreviation: DBTFLP-III) and 4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]-6-phenyldibenzothiophene (abbreviation: DBTFLP-IV), and compounds having a furan skeleton such as 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzofuran) (abbreviation: DBF3P-II) and 4-{3-[3-(9-phenyl-9H-fluoren-9-yl)phenyl]phenyl}dibenzofuran (abbreviation: mmDBFFLBi-II). Among the above, compounds having an aromatic amine skeleton and compounds having a carbazole skeleton are preferable because they have good reliability, high hole transportability, and contribute to reducing the driving voltage. Note that the substances exemplified as the materials having hole transport properties used for the composite material of the hole injection layer 111 can also be suitably used as the material for forming the hole transport layer 112.

[0146] The light-emitting layer 113 is a layer containing a host material and a light-emitting material. The light-emitting material may be a fluorescent material, a phosphorescent material, a material exhibiting thermally activated delayed fluorescence (TADF), or other light-emitting material. The light-emitting layer 113 may be a single layer or may be composed of multiple layers containing different light-emitting materials.

[0147] Examples of materials that can be used as the fluorescent substance in the light-emitting layer 113 include the following: In addition, fluorescent substances other than these can also be used.

[0148] 5,6-bis[4-(10-phenyl-9-anthryl)phenyl]-2,2'-bipyridine (abbreviation: PAP2BPy), 5,6-bis[4'-(10-phenyl-9-anthryl)biphenyl-4-yl]-2,2'-bipyridine (abbreviation: PAPP2BPy), N,N'-diphenyl-N,N'-bis[4-(9-phenyl-9H-fluoren-9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6FLPAPrn), N,N'-bis(3-methylphenyl)-N,N'-bis[3-(9-phenyl-9H-fluoren-9-yl) phenyl]pyrene-1,6-diamine (abbreviation: 1,6mMemFLPAPrn), N,N'-bis[4-(9H-carbazol-9-yl)phenyl]-N,N'-diphenylstilbene-4,4'-diamine (abbreviation: YGA2S), 4-(9H-carbazol-9-yl)-4'-(10-phenyl-9-anthryl)triphenylamine (abbreviation: YGAPA), 4-(9H-carbazol-9-yl)-4'-(9,10-diphenyl-2-anthryl)triphenylamine (abbreviation: 2YGAPPA), N,9-diphenyl-N-[4-(1 0-phenyl-9-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: PCAPA), perylene, 2,5,8,11-tetra(tert-butyl)perylene (abbreviation: TBP), 4-(10-phenyl-9-anthryl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBAPA), 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-carbazol-3-amine (abbreviation: 2PCAPPA), N-[4-(9,10-diphenyl-2-anthryl)phenyl]-N,N',N'-triphenyl-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-(9,10-diphenyl-2-anthryl)-N,9-Diphenyl-9H-carbazol-3-amine (abbreviation: 2PCAPA), N-[9,10-bis(1,1'-biphenyl-2-yl)-2-anthryl]-N,9-diphenyl-9H-carbazol-3-amine (abbreviation: 2PCABPhA), N-(9,10-diphenyl-2-anthryl)-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPA), N-[9,10-bis(1,1'-biphenyl-2-yl)-2-anthryl]-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation: 2DPA BPhA), 9,10-bis(1,1'-biphenyl-2-yl)-N-[4-(9H-carbazol-9-yl)phenyl]-N-phenylanthracen-2-amine (abbreviation: 2YGABPhA), N,N,9-triphenylanthracen-9-amine (abbreviation: DPhAPhA) Coumarin 545T, N,N'-diphenylquinacridone, (abbreviation: DPQd), rubrene, 5,12-bis(1,1'-biphenyl-4-yl)-6,11-diphenyltetracene (abbreviation: BPT), 2-(2-{2-[4-(dimethylamino)phenyl]ethenyl}-6 -methyl-4H-pyran-4-ylidene)propanedinitrile (abbreviation: DCM1), 2-{2-methyl-6-[2-(2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCM2), N,N,N',N'-tetrakis(4-methylphenyl)tetracene-5,11-diamine (abbreviation: p-mPhTD), 7,14-diphenyl-N,N,N',N'-tetrakis(4-methylphenyl)acenaphtho[1,2-a]fluoranthene-3,10-diamine Amine (abbreviation: p-mPhAFD), 2-{2-isopropyl-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTI), 2-{2-tert-butyl-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCJTB), 2-(2,6-bis{2-[4-(dimethylamino)phenyl]ethenyl}-4H-pyran-4-ylidene)propanedinitrile (abbreviation: BisDCM), 2-{2,6-bis[2-(8-methoxy-1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: BisDCJTM), N,N'-(pyren-1,6-diyl)bis[(6,N-diphenylbenzo[b]naphtho[1,2-d]furan)-8-amine] (abbreviation: 1,6BnfAPrn-03), and the like. In particular, condensed aromatic diamine compounds, such as pyrene diamine compounds, such as 1,6FLPAPrn, 1,6mMemFLPAPrn, and 1,6BnfAPrn-03, are preferred because they have high hole trapping properties, excellent luminous efficiency, and excellent reliability.

[0149] Examples of materials that can be used as the phosphorescent material in the light-emitting layer 113 include the following:

[0150] Tris{2-[5-(2-methylphenyl)-4-(2,6-dimethylphenyl)-4H-1,2,4-triazol-3-yl-κN2]phenyl-κC}iridium(III) (abbreviation: [Ir(mpptz-dmp) 3 ]), tris(5-methyl-3,4-diphenyl-4H-1,2,4-triazolato)iridium(III) (abbreviation: [Ir(Mptz) 3 ]), tris[4-(3-biphenyl)-5-isopropyl-3-phenyl-4H-1,2,4-triazolato]iridium(III) (abbreviation: [Ir(iPrptz-3b) 3 ]), and tris[3-methyl-1-(2-methylphenyl)-5-phenyl-1H-1,2,4-triazolato]iridium(III) (abbreviation: [Ir(Mptz1-mp) 3 ]), tris(1-methyl-5-phenyl-3-propyl-1H-1,2,4-triazolato)iridium(III) (abbreviation: [Ir(Prptz1-Me) 3]), and fac-tris[1-(2,6-diisopropylphenyl)-2-phenyl-1H-imidazole]iridium(III) (abbreviation: [Ir(iPrpmi) 3 ]), tris[3-(2,6-dimethylphenyl)-7-methylimidazo[1,2-f]phenanthridinato]iridium(III) (abbreviation: [Ir(dmpimpt-Me 3 ]) and bis[2-(4',6'-difluorophenyl)pyridinato-N,C 2’ ]iridium(III) tetrakis(1-pyrazolyl)borate (abbreviation: FIr6), bis[2-(4',6'-difluorophenyl)pyridinato-N,C 2’ ]iridium(III) picolinate (abbreviation: FIrpic), bis{2-[3',5'-bis(trifluoromethyl)phenyl]pyridinato-N,C 2’}Iridium(III) picolinate (abbreviation: [Ir(CF 3 ppy) 2 (pic)]), bis[2-(4',6'-difluorophenyl)pyridinato-N,C 2’ ] Organometallic iridium complexes with phenylpyridine derivatives having electron-withdrawing groups as ligands, such as iridium(III) acetylacetonate (abbreviated as FIracac), are examples of such compounds that exhibit blue phosphorescence and have emission peaks at 440 nm to 520 nm.

[0151] In addition, tris(4-methyl-6-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mppm) 3 ]), tris(4-t-butyl-6-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(tBuppm) 3 ]), (acetylacetonato)bis(6-methyl-4-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mppm) 2(acac)]), (acetylacetonato)bis(6-tert-butyl-4-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(tBuppm) 2 (acac)]), (acetylacetonato)bis[6-(2-norbornyl)-4-phenylpyrimidinato]iridium(III) (abbreviation: [Ir(nbppm) 2 (acac)]), (acetylacetonato)bis[5-methyl-6-(2-methylphenyl)-4-phenylpyrimidinato]iridium(III) (abbreviation: [Ir(mpmppm) 2 (acac)]), (acetylacetonato)bis(4,6-diphenylpyrimidinato)iridium(III) (abbreviation: [Ir(dppm) 2 and organometallic iridium complexes with pyrimidine skeletons such as (acetylacetonato)bis(3,5-dimethyl-2-phenylpyrazinate)iridium(III) (abbreviation: [Ir(mppr-Me 2 (acac)]), (acetylacetonato)bis(5-isopropyl-3-methyl-2-phenylpyrazinate)iridium(III) (abbreviation: [Ir(mppr-iPr) 2 Organometallic iridium complexes with pyrazine skeletons such as tris(2-phenylpyridinato-N,C 2’ ) Iridium(III) (abbreviation: [Ir(ppy) 3 ]), bis(2-phenylpyridinato-N,C 2’ ) Iridium(III) acetylacetonate (abbreviation: [Ir(ppy) 2 (acac)]), bis(benzo[h]quinolinato)iridium(III) acetylacetonate (abbreviation: [Ir(bzq) 2 (acac)]), tris(benzo[h]quinolinato)iridium(III) (abbreviation: [Ir(bzq) 3 ]), tris(2-phenylquinolinato-N,C 2’ ) Iridium(III) (abbreviation: [Ir(pq) 3 ]), bis(2-phenylquinolinato-N,C 2’ ) Iridium(III) acetylacetonate (abbreviation: [Ir(pq) 2In addition to organometallic iridium complexes with pyridine skeletons such as tris(acetylacetonato)(monophenanthroline)terbium(III) (abbreviation: [Tb(acac)]), 3 These are compounds that mainly exhibit green phosphorescence, with an emission peak at 500 nm to 600 nm. In addition, organometallic iridium complexes having a pyrimidine skeleton are particularly preferred because they are remarkably excellent in reliability and luminous efficiency.

[0152] Also, (diisobutyrylmethanato)bis[4,6-bis(3-methylphenyl)pyrimidinato]iridium(III) (abbreviation: [Ir(5mdppm) 2 (dibm)]), bis[4,6-bis(3-methylphenyl)pyrimidinato](dipivaloylmethanato)iridium(III) (abbreviation: [Ir(5mdppm) 2 (dpm)]), bis[4,6-di(naphthalen-1-yl)pyrimidinato](dipivaloylmethanato)iridium(III) (abbreviation: [Ir(d1npm) 2 and organometallic iridium complexes with pyrimidine skeletons such as (acetylacetonato)bis(2,3,5-triphenylpyrazinate)iridium(III) (abbreviation: [Ir(tppr) 2 (acac)]), bis(2,3,5-triphenylpyrazinate)(dipivaloylmethanato)iridium(III) (abbreviation: [Ir(tppr) 2 (dpm)]), (acetylacetonato)bis[2,3-bis(4-fluorophenyl)quinoxalinato]iridium(III) (abbreviation: [Ir(Fdpq) 2 Organometallic iridium complexes with pyrazine skeletons such as tris(1-phenylisoquinolinato-N,C 2’ ) Iridium(III) (abbreviation: [Ir(piq) 3 ]), bis(1-phenylisoquinolinato-N,C 2’ ) Iridium(III) acetylacetonate (abbreviation: [Ir(piq) 2In addition to organometallic iridium complexes with pyridine skeletons such as iridium complexes with pyridine skeletons such as 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrin platinum(II) (abbreviation: PtOEP), platinum complexes such as tris(1,3-diphenyl-1,3-propanedionato)(monophenanthroline)europium(III) (abbreviation: [Eu(DBM) 3 (Phen)]), tris[1-(2-thenoyl)-3,3,3-trifluoroacetonato](monophenanthroline)europium(III) (abbreviation: [Eu(TTA) 3 These are compounds that exhibit red phosphorescence, with emission peaks at 600 to 700 nm. In addition, organometallic iridium complexes with a pyrazine skeleton can emit red light with good chromaticity.

[0153] In addition to the phosphorescent compounds described above, known phosphorescent light-emitting materials may be selected and used.

[0154] Examples of TADF materials that can be used include fullerene and its derivatives, acridine and its derivatives, and eosin derivatives. Examples of metal-containing porphyrins that can be used include those containing magnesium (Mg), zinc (Zn), cadmium (Cd), tin (Sn), platinum (Pt), indium (In), or palladium (Pd). Examples of metal-containing porphyrins include protoporphyrin-tin fluoride complex (SnF), which is shown in the following structural formula: 2 (Proto IX)), mesoporphyrin-tin fluoride complex (SnF 2 (Meso IX)), hematoporphyrin-tin fluoride complex (SnF 2 (Hemato IX)), coproporphyrin tetramethyl ester-tin fluoride complex (SnF 2 (Copro III-4Me)), octaethylporphyrin-tin fluoride complex (SnF 2 (OEP)), etioporphyrin-tin fluoride complex (SnF 2 (Etio I)), octaethylporphyrin-platinum chloride complex (PtCl 2OEP) etc.

[0155] [ka]

[0156] In addition, 2-(biphenyl-4-yl)-4,6-bis(12-phenylindolo[2,3-a]carbazol-11-yl)-1,3,5-triazine (abbreviation: PIC-TRZ), 9-(4,6-diphenyl-1,3,5-triazin-2-yl)-9'-phenyl-9H,9'H-3,3'-bicarbazole (abbreviation: PCCzTzn), 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol-9-yl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviation: PCCzPTzn), 2-[4-(10H-phenoxazin-10-yl)phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviation: PCCzPTzn), Heterocyclic compounds having one or both of a π-electron rich heteroaromatic ring and a π-electron deficient heteroaromatic ring, such as 3-[4-(5-phenyl-5,10-dihydrophenazin-10-yl)phenyl]-4,5-diphenyl-1,2,4-triazole (abbreviation: PPZ-3TPT), 3-(9,9-dimethyl-9H-acridin-10-yl)-9H-xanthen-9-one (abbreviation: ACRXTN), bis[4-(9,9-dimethyl-9,10-dihydroacridine)phenyl]sulfone (abbreviation: DMAC-DPS), and 10-phenyl-10H,10'H-spiro[acridin-9,9'-anthracene]-10'-one (abbreviation: ACRSA), can also be used. The heterocyclic compound has a π-electron rich heteroaromatic ring and a π-electron deficient heteroaromatic ring, and therefore has high electron transport and hole transport properties, and is therefore preferred. Among the skeletons having a π-electron deficient heteroaromatic ring, the pyridine skeleton, the diazine skeleton (pyrimidine skeleton, pyrazine skeleton, pyridazine skeleton), and the triazine skeleton are preferred because they are stable and reliable. In particular, the benzofuropyrimidine skeleton, the benzothienopyrimidine skeleton, the benzofuropyrazine skeleton, and the benzothienopyrazine skeleton are preferred because they have high acceptor properties and good reliability. In addition, among the skeletons having a π-electron rich heteroaromatic ring, the acridine skeleton, the phenoxazine skeleton, the phenothiazine skeleton, the furan skeleton, the thiophene skeleton, and the pyrrole skeleton are preferred because they are stable and reliable.In addition, the furan skeleton is preferably a dibenzofuran skeleton, and the thiophene skeleton is preferably a dibenzothiophene skeleton. In addition, the pyrrole skeleton is particularly preferably an indole skeleton, a carbazole skeleton, an indolocarbazole skeleton, a bicarbazole skeleton, or a 3-(9-phenyl-9H-carbazole-3-yl)-9H-carbazole skeleton. In addition, in a substance in which a π-electron rich heteroaromatic ring and a π-electron deficient heteroaromatic ring are directly bonded, both the electron donating property of the π-electron rich heteroaromatic ring and the electron accepting property of the π-electron deficient heteroaromatic ring become strong, and the substance is S. 1 Level and T 1 Since the energy difference between the levels is small, it is particularly preferable because thermally activated delayed fluorescence can be efficiently obtained. In addition, an aromatic ring to which an electron-withdrawing group such as a cyano group is bonded may be used instead of the π-electron-deficient heteroaromatic ring. In addition, an aromatic amine skeleton, a phenazine skeleton, or the like can be used as the π-electron-rich skeleton. In addition, as the π-electron-deficient skeleton, a xanthene skeleton, a thioxanthene dioxide skeleton, an oxadiazole skeleton, a triazole skeleton, an imidazole skeleton, an anthraquinone skeleton, a boron-containing skeleton such as phenylborane or boranthrene, an aromatic ring or a heteroaromatic ring having a nitrile group or a cyano group such as benzonitrile or cyanobenzene, a carbonyl skeleton such as benzophenone, a phosphine oxide skeleton, a sulfone skeleton, or the like can be used. In this way, a π-electron-deficient skeleton and a π-electron-rich skeleton can be used instead of at least one of the π-electron-deficient heteroaromatic ring and the π-electron-rich heteroaromatic ring.

[0157] [ka]

[0158] TADF materials are materials that have a small difference between the S1 and T1 levels and have the function of converting triplet excitation energy to singlet excitation energy by reverse intersystem crossing. Therefore, triplet excitation energy can be upconverted to singlet excitation energy by a small amount of thermal energy (reverse intersystem crossing), and singlet excitation states can be generated efficiently. In addition, triplet excitation energy can be converted into light emission.

[0159] In addition, exciplexes (also called exciplexes), which form an excited state with two types of substances, have an extremely small difference between the S1 level and the T1 level and function as TADF materials that can convert triplet excitation energy into singlet excitation energy.

[0160] As an index of the T1 level, a phosphorescence spectrum observed at low temperatures (for example, 77 K to 10 K) may be used. For a TADF material, when a tangent is drawn at the base of the short wavelength side of the fluorescence spectrum, and the energy of the wavelength of the extrapolated line is taken as the S1 level, and a tangent is drawn at the base of the short wavelength side of the phosphorescence spectrum, and the energy of the wavelength of the extrapolated line is taken as the T1 level, the difference between S1 and T1 is preferably 0.3 eV or less, and more preferably 0.2 eV or less.

[0161] In addition, when a TADF material is used as the emission center material, the S1 level of the host material is preferably higher than the S1 level of the TADF material, and the T1 level of the host material is preferably higher than the T1 level of the TADF material.

[0162] As the host material of the light-emitting layer, various carrier transporting materials such as a material having an electron transporting property, a material having a hole transporting property, or the above-mentioned TADF material can be used.

[0163] As the material having a hole-transporting property, the substances exemplified as the material having a hole-transporting property contained in the hole-transporting layer 112 can be suitably used.

[0164] An example of a material having electron transport properties is bis(10-hydroxybenzo[h]quinolinato)beryllium(II) (abbreviation: BeBq 2), bis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum(III) (abbreviation: BAlq), bis(8-quinolinolato)zinc(II) (abbreviation: Znq), bis[2-(2-benzoxazolyl)phenolato]zinc(II) (abbreviation: ZnPBO), bis[2-(2-benzothiazolyl)phenolato]zinc(II) (abbreviation: ZnBTZ), and other metal complexes. p-tert-butylphenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (abbreviation: TAZ), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene (abbreviation: OXD-7), 9-[4-(5-phenyl-1,3,4-oxadiazol-2-yl)phenyl]-9H-carbazole (abbreviation: CO11), 2,2',2''-(1,3,5-benzenetriyl)tris(1-phenyl-1H-benzimidazole) (abbreviation: TPBI), 2-[3-(dibenzothiophene-4-yl) We have developed heterocyclic compounds with polyazole skeletons such as 2-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTPDBq-II), 2-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II), 2-[3'-(9H-carbazol-9-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2 Examples of heterocyclic compounds having a diazine skeleton include 4,6-bis[3-(phenanthren-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm), and 4,6-bis[3-(4-dibenzothienyl)phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-II), and heterocyclic compounds having a pyridine skeleton include 3,5-bis[3-(9H-carbazol-9-yl)phenyl]pyridine (abbreviation: 35DCzPPy), and 1,3,5-tri[3-(3-pyridyl)phenyl]benzene (abbreviation: TmPyPB).Among the above, heterocyclic compounds having a diazine skeleton and heterocyclic compounds having a pyridine skeleton are preferable because of their high reliability. In particular, heterocyclic compounds having a diazine (pyrimidine or pyrazine) skeleton have high electron transport properties and contribute to reducing the driving voltage.

[0165] When a fluorescent material is used as the light-emitting material, a material having an anthracene skeleton is suitable as the host material. When a material having an anthracene skeleton is used as the host material of the fluorescent material, it is possible to realize a light-emitting layer having both good light-emitting efficiency and durability. Since many materials having an anthracene skeleton have a deep HOMO level, one embodiment of the present invention can be suitably applied. As a material having an anthracene skeleton to be used as a host material, a diphenylanthracene skeleton, particularly a 9,10-diphenylanthracene skeleton, is preferable because it is chemically stable. In addition, when the host material has a carbazole skeleton, it is preferable because the hole injection and transport properties are improved, but when the host material contains a benzocarbazole skeleton in which a benzene ring is further condensed to carbazole, the HOMO is shallower by about 0.1 eV than carbazole, making it easier for holes to enter, which is more preferable. In particular, when the host material contains a dibenzocarbazole skeleton, it is preferable because the HOMO is shallower by about 0.1 eV than carbazole, making it easier for holes to enter, and it also has excellent hole transport properties and high heat resistance. Therefore, more preferable host materials are those having both a 9,10-diphenylanthracene skeleton and a carbazole skeleton (or a benzocarbazole skeleton or a dibenzocarbazole skeleton). From the viewpoint of the hole injection / transport property, a benzofluorene skeleton or a dibenzofluorene skeleton may be used instead of the carbazole skeleton. Examples of such materials include 9-phenyl-3-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviation: PCzPA), 3-[4-(1-naphthyl)-phenyl]-9-phenyl-9H-carbazole (abbreviation: PCPN), 9-[4-(N-carbazolyl)]phenyl-10-phenylanthracene (abbreviation: CzPA), 7-[4-(10-phenyl-9-anthryl)phenyl]-10-phenylanthracene (abbreviation: CzPA), and 7-[4-(10-phenyl-9-anthryl)phenyl]-10-phenylanthracene (abbreviation: CzPA). tolyl)phenyl]-7H-dibenzo[c,g]carbazole (abbreviation: cgDBCzPA), 6-[3-(9,10-diphenyl-2-anthryl)phenyl]-benzo[b]naphtho[1,2-d]furan (abbreviation: 2mBnfPPA), 9-phenyl-10-{4-(9-phenyl-9H-fluoren-9-yl)biphenyl-4'-yl}anthracene (abbreviation: FLPPA), and the like.In particular, CzPA, cgDBCzPA, 2mBnfPPA, and PCzPA are preferred choices since they exhibit very good properties.

[0166] The host material may be a mixture of a plurality of substances, and when a mixture of host materials is used, it is preferable to mix a material having an electron transporting property with a material having a hole transporting property. By mixing a material having an electron transporting property with a material having a hole transporting property, the transporting property of the light-emitting layer 113 can be easily adjusted, and the recombination region can be easily controlled. The content ratio of the material having a hole transporting property to the material having an electron transporting property may be 1:9 to 9:1 (material having a hole transporting property:material having an electron transporting property).

[0167] In addition, these mixed materials may form an exciplex. It is preferable to select a combination that forms an exciplex that emits light that overlaps with the wavelength of the lowest energy absorption band of the light-emitting material, because this makes energy transfer smooth and allows efficient light emission. In addition, the use of this structure is preferable because the driving voltage is reduced.

[0168] The electron transport layer 114 is a layer containing a substance having an electron transport property. As the substance having an electron transport property, any of the substances exemplified above as the substance having an electron transport property that can be used as the host material can be used.

[0169] Between the electron transport layer 114 and the cathode 102, an electron injection layer 115 is formed using a material such as lithium fluoride (LiF), cesium fluoride (CsF), or calcium fluoride (CaF 2 The electron injection layer 115 may be a layer containing an alkali metal or alkaline earth metal or a compound thereof, such as ZnO, ZnSe ...

[0170] Note that a layer containing a fluoride of the above alkali metal or alkaline earth metal in a substance having an electron transporting property (preferably an organic compound having a bipyridine skeleton) at a concentration at which the fluoride is in a microcrystalline state or higher (50 wt % or higher) can be used as the electron-injection layer 115. Since this layer has a low refractive index, it is possible to provide an EL device with better external quantum efficiency.

[0171] Alternatively, a charge generation layer 116 may be provided instead of the electron injection layer 115 (FIG. 1B). The charge generation layer 116 is a layer capable of injecting holes into a layer in contact with the cathode side of the layer and electrons into a layer in contact with the anode side of the layer by applying a potential. The charge generation layer 116 includes at least a P-type layer 117. The P-type layer 117 is preferably formed using the composite material listed above as a material capable of forming the hole injection layer 111. The P-type layer 117 may also be formed by laminating a film containing an acceptor material and a film containing a hole transport material, both of which are materials that constitute the composite material. By applying a potential to the P-type layer 117, electrons are injected into the electron transport layer 114 and holes are injected into the cathode 102, which is the cathode, and the EL device operates. The first layer may also be used as the P-type layer 117. This makes it possible to form a P-type layer 117 with a low refractive index, and an EL device with good external quantum efficiency can be obtained.

[0172] It is preferable that the charge generating layer 116 is provided with either or both of an electron relay layer 118 and an electron injection buffer layer 119 in addition to the P-type layer 117 .

[0173] The electron relay layer 118 contains at least a substance having electron transport properties, and has a function of preventing interaction between the electron injection buffer layer 119 and the P-type layer 117 and smoothly transferring electrons. The LUMO level of the substance having electron transport properties contained in the electron relay layer 118 is preferably between the LUMO level of the electron accepting substance in the P-type layer 117 and the LUMO level of the substance contained in the layer in contact with the charge generation layer 116 in the electron transport layer 114. The specific energy level of the LUMO level of the substance having electron transport properties used in the electron relay layer 118 is -5.0 eV or more, preferably -5.0 eV or more and -3.0 eV or less. Note that the substance having electron transport properties used in the electron relay layer 118 is preferably a phthalocyanine-based material or a metal complex having a metal-oxygen bond and an aromatic ligand.

[0174] The electron injection buffer layer 119 can be made of a material with high electron injection properties, such as an alkali metal, an alkaline earth metal, a rare earth metal, or a compound thereof (an alkali metal compound (including an oxide such as lithium oxide, a halide, or a carbonate such as lithium carbonate or cesium carbonate), an alkaline earth metal compound (including an oxide, a halide, or a carbonate), or a rare earth metal compound (including an oxide, a halide, or a carbonate)).

[0175] In addition, when the electron-injection buffer layer 119 is formed containing a substance having an electron-transporting property and a donor substance, as the donor substance, an alkali metal, an alkaline earth metal, a rare earth metal, and a compound thereof (an alkali metal compound (including an oxide such as lithium oxide, a halide, or a carbonate such as lithium carbonate or cesium carbonate), an alkaline earth metal compound (including an oxide, a halide, or a carbonate), or a rare earth metal compound (including an oxide, a halide, or a carbonate)), or an organic compound such as tetrathianaphthacene (abbreviation: TTN), nickelocene, or decamethylnickelocene can be used. Note that as the substance having an electron-transporting property, a material similar to the material constituting the electron-transporting layer 114 described above can be used.

[0176] As a material for forming the cathode 102, metals, alloys, electrically conductive compounds, and mixtures thereof having a small work function (specifically, 3.8 eV or less) can be used. Specific examples of such cathode materials include alkali metals such as lithium (Li) and cesium (Cs), elements belonging to Group 1 or Group 2 of the periodic table such as magnesium (Mg), calcium (Ca), and strontium (Sr), and alloys containing these (MgAg, AlLi), rare earth metals such as europium (Eu), ytterbium (Yb), and alloys containing these. However, by providing an electron injection layer between the cathode 102 and the electron transport layer, various conductive materials such as Al, Ag, ITO, indium oxide-tin oxide containing silicon or silicon oxide can be used as the cathode 102 regardless of the magnitude of the work function. These conductive materials can be formed into films using dry methods such as vacuum deposition and sputtering, inkjet methods, spin coating methods, and the like. Also, it may be formed by a wet method using a sol-gel method, or may be formed by a wet method using a paste of a metal material.

[0177] In addition, various methods, whether dry or wet, can be used to form the EL layer 103. For example, a vacuum deposition method, a gravure printing method, an offset printing method, a screen printing method, an inkjet method, or a spin coating method may be used.

[0178] Moreover, the above-mentioned electrodes or layers may be formed using different film formation methods.

[0179] The configuration of the layer provided between the anode 101 and the cathode 102 is not limited to the above. However, a configuration in which a light-emitting region where holes and electrons recombine is provided at a position away from the anode 101 and the cathode 102 is preferable so as to suppress quenching caused by the proximity of the light-emitting region to metals used in the electrodes and the carrier injection layer.

[0180] In addition, the hole transport layer and electron transport layer in contact with the light-emitting layer 113, particularly the carrier transport layer close to the recombination region in the light-emitting layer 113, are preferably composed of a substance having a band gap larger than the band gap of the light-emitting material constituting the light-emitting layer or the light-emitting material contained in the light-emitting layer, in order to suppress energy transfer from excitons generated in the light-emitting layer.

[0181] Next, an embodiment of an EL device having a configuration in which a plurality of light-emitting units are stacked (also called a stacked element or a tandem element) will be described with reference to Fig. 1C. This EL device has a plurality of light-emitting units between an anode and a cathode. One light-emitting unit has a configuration almost similar to that of the EL layer 103 shown in Fig. 1A. In other words, it can be said that the EL device shown in Fig. 1C is an EL device having a plurality of light-emitting units, and the EL device shown in Fig. 1A or 1B is an EL device having one light-emitting unit.

[0182] 1C, a first light-emitting unit 511 and a second light-emitting unit 512 are laminated between an anode 501 and a cathode 502, and a charge generation layer 513 is provided between the first light-emitting unit 511 and the second light-emitting unit 512. The anode 501 and the cathode 502 correspond to the anode 101 and the cathode 102 in FIG. 1A, respectively, and the same as those described in the description of FIG. 1A can be applied. In addition, the first light-emitting unit 511 and the second light-emitting unit 512 may have the same configuration or different configurations.

[0183] Charge generation layer 513 has a function of injecting electrons into one light-emitting unit and injecting holes into the other light-emitting unit when a voltage is applied between anode 501 and cathode 502. That is, when a voltage is applied so that the potential of the anode is higher than the potential of the cathode in FIG. 1C, charge generation layer 513 only needs to inject electrons into first light-emitting unit 511 and inject holes into second light-emitting unit 512.

[0184] The charge generation layer 513 is preferably formed in the same structure as the charge generation layer 116 described in FIG. 1B. A composite material of an organic compound and a metal oxide has excellent carrier injection and carrier transport properties, and therefore can realize low-voltage driving and low-current driving. When the anode side surface of the light-emitting unit is in contact with the charge generation layer 513, the charge generation layer 513 can also play the role of the hole injection layer of the light-emitting unit, so that the light-emitting unit does not need to be provided with a hole injection layer.

[0185] Furthermore, when an electron injection buffer layer 119 is provided in the charge generation layer 513, the electron injection buffer layer 119 plays the role of an electron injection layer in the light-emitting unit on the anode side, so that it is not necessarily necessary to form an electron injection layer in the light-emitting unit on the anode side.

[0186] 1C, an EL device having two light-emitting units has been described, but the present invention can be applied to an EL device having three or more light-emitting units stacked in the same manner. By disposing a plurality of light-emitting units between a pair of electrodes and separating them with a charge generating layer 513 as in the EL device according to the present embodiment, it is possible to realize an element that can emit light with high luminance while keeping the current density low and has a long life. In addition, it is possible to realize a light-emitting device that can be driven at a low voltage and consumes low power.

[0187] In addition, by making the emission colors of the respective light-emitting units different, it is possible to obtain light emission of a desired color from the entire EL device. For example, in an EL device having two light-emitting units, it is possible to obtain an EL device that emits white light from the entire EL device by obtaining red and green emission colors from the first light-emitting unit and blue emission color from the second light-emitting unit.

[0188] In addition, each layer and electrode such as the above-mentioned EL layer 103, the first light-emitting unit 511, the second light-emitting unit 512, and the charge generation layer can be formed by using, for example, a deposition method (including a vacuum deposition method), a droplet discharge method (also called an ink-jet method), a coating method, a gravure printing method, etc. In addition, they may contain a low molecular weight material, a medium molecular weight material (including an oligomer and a dendrimer), or a polymer material.

[0189] (Embodiment 3) In this embodiment mode, a light-emitting device using the EL device described in Embodiment 2 will be described.

[0190] In this embodiment, a light-emitting device manufactured using the EL device described in Embodiment 2 will be described with reference to FIG. 2. FIG. 2A is a top view showing the light-emitting device, and FIG. 2B is a cross-sectional view taken along the lines AB and CD in FIG. 2A. This light-emitting device includes a driver circuit section (source line driver circuit) 601, a pixel section 602, and a driver circuit section (gate line driver circuit) 603, all of which are shown by dotted lines, for controlling the light emission of the EL device. Reference numeral 604 denotes a sealing substrate, 605 denotes a sealant, and the inside surrounded by the sealant 605 defines a space 607.

[0191] The lead wiring 608 is a wiring for transmitting signals input to the source line driving circuit 601 and the gate line driving circuit 603, and receives a video signal, a clock signal, a start signal, a reset signal, and the like from an FPC (flexible printed circuit) 609 serving as an external input terminal. Although only an FPC is shown here, a printed wiring board (PWB) may be attached to this FPC. In this specification, the light emitting device includes not only the light emitting device itself, but also a state in which an FPC or a PWB is attached to it.

[0192] Next, the cross-sectional structure will be described with reference to Fig. 2B. A driver circuit section and a pixel section are formed on an element substrate 610, and here, a source line driver circuit 601, which is the driver circuit section, and one pixel in a pixel section 602 are shown.

[0193] The element substrate 610 may be made of a substrate made of glass, quartz, organic resin, metal, alloy, semiconductor, or a plastic substrate made of FRP (Fiber Reinforced Plastics), PVF (Polyvinyl fluoride), polyester, acrylic resin, or the like.

[0194] The structure of the transistor used in the pixel or the driver circuit is not particularly limited. For example, the transistor may be an inverted staggered type transistor or a staggered type transistor. In addition, the transistor may be a top-gate type transistor or a bottom-gate type transistor. The semiconductor material used for the transistor is not particularly limited, and for example, silicon, germanium, silicon carbide, gallium nitride, or the like may be used. Alternatively, an oxide semiconductor containing at least one of indium, gallium, and zinc, such as an In-Ga-Zn-based metal oxide, may be used.

[0195] The crystallinity of a semiconductor material used for a transistor is not particularly limited, and any of an amorphous semiconductor and a crystalline semiconductor (a microcrystalline semiconductor, a polycrystalline semiconductor, a single crystal semiconductor, or a semiconductor having a crystalline region in a part) may be used. The use of a crystalline semiconductor is preferable because it can suppress deterioration of transistor characteristics.

[0196] Here, in addition to the transistors provided in the pixels and driver circuits, an oxide semiconductor is preferably used for semiconductor devices such as transistors used in touch sensors, which will be described later. In particular, an oxide semiconductor having a wider band gap than silicon is preferably used. By using an oxide semiconductor having a wider band gap than silicon, the current in the off state of the transistor can be reduced.

[0197] The oxide semiconductor preferably contains at least indium (In) or zinc (Zn), and more preferably contains an oxide represented by In-M-Zn oxide (M is a metal such as Al, Ti, Ga, Ge, Y, Zr, Sn, La, Ce, or Hf).

[0198] Here, an oxide semiconductor that can be used in one embodiment of the present invention is described below.

[0199] Oxide semiconductors are classified into single-crystal oxide semiconductors and non-single-crystal oxide semiconductors other than those mentioned above. Examples of non-single-crystal oxide semiconductors include c-axis aligned crystalline oxide semiconductors (CAAC-OS), polycrystalline oxide semiconductors, nano crystalline oxide semiconductors (nc-OS), amorphous-like oxide semiconductors (a-like OS), and amorphous oxide semiconductors.

[0200] CAAC-OS has a c-axis orientation and a distorted crystal structure in which multiple nanocrystals are connected in the ab-plane direction. The distortion refers to a portion where the lattice orientation changes between a region with a uniform lattice arrangement and a region with a different uniform lattice arrangement in the region where multiple nanocrystals are connected.

[0201] Nanocrystals are basically hexagonal, but may be non-regular hexagonal. In addition, the lattice arrangement may be pentagonal or heptagonal due to the distortion. It is difficult to confirm clear grain boundaries in CAAC-OS even near the distortion. In other words, it is found that the formation of grain boundaries is suppressed by the distortion of the lattice arrangement. This is because CAAC-OS can tolerate distortion due to the lack of dense arrangement of oxygen atoms in the ab-plane direction and the change in the bond distance between atoms due to the substitution of metal elements.

[0202] CAAC-OS also tends to have a layered crystal structure (also referred to as a layered structure) in which a layer containing indium and oxygen (hereinafter, In layer) and a layer containing element M, zinc, and oxygen (hereinafter, (M, Zn) layer) are stacked. Note that indium and element M can be substituted for each other, and when element M in an (M, Zn) layer is substituted for indium, it can also be expressed as an (In, M, Zn) layer. When indium in an In layer is substituted for element M, it can also be expressed as an (In, M) layer.

[0203] CAAC-OS is an oxide semiconductor with high crystallinity. On the other hand, it is difficult to identify clear crystal boundaries in CAAC-OS, so it can be said that the decrease in electron mobility caused by crystal boundaries is unlikely to occur. In addition, the crystallinity of oxide semiconductors can be decreased by the introduction of impurities or the generation of defects. Therefore, CAAC-OS is not prone to impurities or defects (oxygen vacancies (V O The oxide semiconductor having the CAAC-OS has stable physical properties. Therefore, the oxide semiconductor having the CAAC-OS has high heat resistance and reliability.

[0204] The nc-OS has periodic atomic arrangement in a microscopic region (for example, a region of 1 nm to 10 nm, particularly a region of 1 nm to 3 nm). In addition, the nc-OS does not show regularity in the crystal orientation between different nanocrystals. Therefore, no orientation is seen throughout the film. Therefore, depending on the analysis method, the nc-OS may be indistinguishable from an a-like OS or an amorphous oxide semiconductor.

[0205] Indium-gallium-zinc oxide (hereinafter, IGZO), a type of oxide semiconductor containing indium, gallium, and zinc, may have a stable structure when made into the above-mentioned nanocrystals. In particular, since IGZO tends to have difficulty in crystal growth in the air, it may be structurally more stable when made into small crystals (for example, the above-mentioned nanocrystals) rather than large crystals (here, crystals of several mm or several cm).

[0206] The a-like OS is an oxide semiconductor having a structure between the nc-OS and an amorphous oxide semiconductor. The a-like OS has a pore or low-density region. That is, the a-like OS has lower crystallinity than the nc-OS and CAAC-OS.

[0207] Oxide semiconductors have a variety of structures and each structure has different characteristics. The oxide semiconductor of one embodiment of the present invention may include two or more of an amorphous oxide semiconductor, a polycrystalline oxide semiconductor, an a-like OS, an nc-OS, and a CAAC-OS.

[0208] As an alternative to the oxide semiconductor, a cloud-aligned composite (CAC)-OS may be used.

[0209] CAC-OS has a conductive function in part of the material and an insulating function in part of the material, and the material as a whole functions as a semiconductor. When CAC-OS is used in the active layer of a transistor, the conductive function is a function of allowing electrons (or holes) to flow as carriers, and the insulating function is a function of not allowing electrons to flow as carriers. By making the conductive function and the insulating function act in a complementary manner, it is possible to give the CAC-OS a switching function (on / off function). By separating the respective functions in CAC-OS, it is possible to maximize both functions.

[0210] The CAC-OS has a conductive region and an insulating region. The conductive region has the above-mentioned conductive function, and the insulating region has the above-mentioned insulating function. In the material, the conductive region and the insulating region may be separated at the nanoparticle level. In addition, the conductive region and the insulating region may be unevenly distributed in the material. In addition, the conductive region may be observed to be connected in a cloud shape with a blurred periphery.

[0211] In addition, in the CAC-OS, the conductive regions and the insulating regions may each be dispersed in the material with a size of 0.5 nm or more and 10 nm or less, preferably 0.5 nm or more and 3 nm or less.

[0212] In addition, the CAC-OS is composed of components having different band gaps. For example, the CAC-OS is composed of a component having a wide gap due to an insulating region and a component having a narrow gap due to a conductive region. In this configuration, when carriers are caused to flow, the carriers mainly flow in the component having the narrow gap. In addition, the component having the narrow gap acts complementarily to the component having the wide gap, and carriers also flow in the component having the wide gap in conjunction with the component having the narrow gap. Therefore, when the above-mentioned CAC-OS is used in the channel formation region of a transistor, a high current driving force, that is, a large on-current and a high field effect mobility can be obtained in the on-state of the transistor.

[0213] That is, CAC-OS can also be called a matrix composite or a metal matrix composite.

[0214] By using the above-described oxide semiconductor material for the semiconductor layer, a change in electrical characteristics can be suppressed, and a highly reliable transistor can be realized.

[0215] In addition, the transistor having the above-mentioned semiconductor layer can hold charge accumulated in a capacitance through the transistor for a long period of time due to its low off-state current. By applying such a transistor to a pixel, it is possible to stop a driver circuit while maintaining the gray level of an image displayed in each display region. As a result, an electronic device with extremely low power consumption can be realized.

[0216] It is preferable to provide an undercoat film in order to stabilize the characteristics of the transistor. The undercoat film can be prepared as a single layer or a multilayer structure using an inorganic insulating film such as a silicon oxide film, a silicon nitride film, a silicon oxynitride film, or a silicon nitride oxide film. The undercoat film can be formed by a sputtering method, a CVD (Chemical Vapor Deposition) method (such as a plasma CVD method, a thermal CVD method, or a MOCVD (Metal Organic CVD) method), an ALD (Atomic Layer Deposition) method, a coating method, a printing method, or the like. Note that the undercoat film need not be provided if it is not necessary.

[0217] The FET 623 indicates one of the transistors formed in the driving circuit section 601. The driving circuit may be formed of various CMOS circuits, PMOS circuits, or NMOS circuits. Although the present embodiment shows a driver-integrated type in which a driving circuit is formed on a substrate, this is not necessarily required, and the driving circuit may be formed externally instead of on the substrate.

[0218] In addition, the pixel section 602 is formed of a plurality of pixels including a switching FET 611, a current control FET 612, and an anode 613 electrically connected to the drain of the FET 612. However, the present invention is not limited to this, and the pixel section may be formed by combining three or more FETs and a capacitive element.

[0219] An insulator 614 is formed to cover the end of the anode 613. Here, the insulator 614 can be formed by using a positive type photosensitive acrylic resin film.

[0220] In order to improve the covering ability of an EL layer or the like to be formed later, a curved surface having a curvature is formed at the upper end or lower end of the insulator 614. For example, when a positive type photosensitive acrylic resin is used as the material of the insulator 614, it is preferable that only the upper end of the insulator 614 has a curved surface having a radius of curvature (0.2 μm to 3 μm). In addition, either a negative type photosensitive resin or a positive type photosensitive resin can be used as the insulator 614.

[0221] An EL layer 616 and a cathode 617 are formed on the anode 613. Here, it is desirable to use a material with a large work function as the material used for the anode 613 that functions as an anode. For example, in addition to a single layer film such as an ITO film, an indium tin oxide film containing silicon, an indium oxide film containing 2 to 20 wt % zinc oxide, a titanium nitride film, a chromium film, a tungsten film, a Zn film, or a Pt film, a laminated structure of a titanium nitride film and a film mainly composed of aluminum, or a three-layer structure of a titanium nitride film, a film mainly composed of aluminum, and a titanium nitride film can be used. Note that a laminated structure has low resistance as wiring, provides good ohmic contact, and can further function as an anode.

[0222] The EL layer 616 is formed by various methods such as a deposition method using a deposition mask, an inkjet method, a spin coating method, etc. The EL layer 616 includes the configuration described in the embodiment 2. Other materials constituting the EL layer 616 may be low molecular weight compounds or high molecular weight compounds (including oligomers and dendrimers).

[0223] Furthermore, the material used for the cathode 617 formed on the EL layer 616 and functioning as a cathode is preferably a material with a small work function (such as Al, Mg, Li, Ca, or alloys or compounds thereof (MgAg, MgIn, AlLi, etc.)). When light generated in the EL layer 616 is transmitted through the cathode 617, it is preferable to use a laminate of a thin metal thin film and a transparent conductive film (ITO, indium oxide containing 2 to 20 wt % zinc oxide, indium tin oxide containing silicon, zinc oxide (ZnO), etc.) as the cathode 617.

[0224] An EL device 618 is formed by the anode 613, the EL layer 616, and the cathode 617. The EL device 618 is the EL device described in Embodiment 2. Although a pixel portion is formed with a plurality of EL devices, the light-emitting device in this embodiment may include both the EL device described in Embodiment 2 and an EL device having a different structure.

[0225] Furthermore, by bonding the sealing substrate 604 to the element substrate 610 with a sealant 605, an EL device 618 is provided in a space 607 surrounded by the element substrate 610, the sealing substrate 604, and the sealant 605. The space 607 is filled with a filler, and may be filled with an inert gas (nitrogen, argon, etc.) or a sealant. A recess is formed in the sealing substrate, and a desiccant is provided therein to suppress deterioration due to the influence of moisture, which is a preferable configuration.

[0226] It is preferable to use epoxy resin or glass frit for the sealing material 605. It is also preferable that these materials are as impermeable to moisture and oxygen as possible. In addition to glass and quartz substrates, materials that can be used for the sealing substrate 604 include plastic substrates made of FRP (Fiber Reinforced Plastics), PVF (Polyvinyl Fluoride), polyester, acrylic resin, etc.

[0227] Although not shown in Fig. 2, a protective film may be provided on the cathode. The protective film may be formed of an organic resin film or an inorganic insulating film. The protective film may be formed so as to cover the exposed portion of the sealant 605. The protective film may be provided so as to cover the surfaces and side surfaces of the pair of substrates, the exposed side surfaces of the sealing layer, the insulating layer, etc.

[0228] The protective film can be made of a material that is difficult for impurities such as water to permeate, and therefore can effectively prevent impurities such as water from diffusing from the outside to the inside.

[0229] The protective film may be made of an oxide, a nitride, a fluoride, a sulfide, a ternary compound, a metal, a polymer, or the like. For example, a material containing aluminum oxide, hafnium oxide, hafnium silicate, lanthanum oxide, silicon oxide, strontium titanate, tantalum oxide, titanium oxide, zinc oxide, niobium oxide, zirconium oxide, tin oxide, yttrium oxide, cerium oxide, scandium oxide, erbium oxide, vanadium oxide, indium oxide, or the like; a material containing aluminum nitride, hafnium nitride, silicon nitride, tantalum nitride, titanium nitride, niobium nitride, molybdenum nitride, zirconium nitride, gallium nitride, or the like; a nitride containing titanium and aluminum; an oxide containing titanium and aluminum; an oxide containing aluminum and zinc; a sulfide containing manganese and zinc; a sulfide containing cerium and strontium; an oxide containing erbium and aluminum; an oxide containing yttrium and zirconium, or the like.

[0230] The protective film is preferably formed using a film formation method with good step coverage. One such method is the atomic layer deposition (ALD) method. It is preferable to use a material that can be formed using the ALD method for the protective film. By using the ALD method, it is possible to form a dense protective film with reduced defects such as cracks and pinholes, or with a uniform thickness. In addition, it is possible to reduce damage to the processed member when forming the protective film.

[0231] For example, by forming a protective film using the ALD method, it is possible to form a uniform protective film with few defects on surfaces with complex uneven shapes, as well as on the top, side, and back surfaces of a touch panel.

[0232] In the above manner, a light-emitting device manufactured using the EL device described in Embodiment 2 can be obtained.

[0233] A light-emitting device with favorable characteristics can be obtained in the light-emitting device of this embodiment because the EL device described in Embodiment 2 is used. Specifically, since the EL device described in Embodiment 2 has favorable luminous efficiency, a light-emitting device with low power consumption can be obtained.

[0234] Fig. 3 shows an example of a light-emitting device in which an EL device that emits white light is formed and a full color is achieved by providing a colored layer (color filter), etc. Fig. 3A shows a substrate 1001, a base insulating film 1002, a gate insulating film 1003, gate electrodes 1006, 1007, 1008, a first interlayer insulating film 1020, a second interlayer insulating film 1021, a peripheral section 1042, a pixel section 1040, a driving circuit section 1041, anodes 1024W, 1024R, 1024G, 1024B of the EL device, a partition wall 1025, an EL layer 1028, a cathode 1029 of the EL device, a sealing substrate 1031, a sealant 1032, etc.

[0235] In FIG. 3A, the colored layers (red colored layer 1034R, green colored layer 1034G, blue colored layer 1034B) are provided on a transparent base material 1033. A black matrix 1035 may be further provided. The transparent base material 1033 on which the colored layers and black matrix are provided is aligned and fixed to the substrate 1001. The colored layers and black matrix 1035 are covered with an overcoat layer 1036. In FIG. 3A, there are light-emitting layers from which light does not pass through the colored layers and goes out, and light-emitting layers from which light passes through the colored layers of each color and goes out. Light that does not pass through the colored layers is white, and light that passes through the colored layers is red, green, and blue, so that an image can be expressed by four color pixels.

[0236] 3B shows an example in which the colored layers (red colored layer 1034R, green colored layer 1034G, and blue colored layer 1034B) are formed between the gate insulating film 1003 and the first interlayer insulating film 1020. In this manner, the colored layers may be provided between the substrate 1001 and the sealing substrate 1031.

[0237] In the light-emitting device described above, the light-emitting device has a structure (bottom emission type) in which light is extracted on the substrate 1001 side on which the FET is formed, but the light-emitting device may have a structure (top emission type) in which light is extracted on the sealing substrate 1031 side. A cross-sectional view of a top emission type light-emitting device is shown in FIG. 4. In this case, a substrate that does not transmit light can be used as the substrate 1001. The process is performed in the same manner as the bottom emission type light-emitting device until a connection electrode that connects the FET and the anode of the EL device is formed. Then, a third interlayer insulating film 1037 is formed to cover the electrode 1022. This insulating film may play a role of planarization. The third interlayer insulating film 1037 can be formed using the same material as the second interlayer insulating film, as well as other known materials.

[0238] Although the anodes 1024W, 1024R, 1024G, and 1024B of the EL device are anodes here, they may be cathodes. In addition, in the case of a top-emission type light-emitting device as shown in FIG. 4, it is preferable that the anodes are reflective electrodes. The EL layer 1028 has the same configuration as that described for the EL layer 103 in the first embodiment, and has an element structure that can emit white light.

[0239] In the top emission structure as shown in FIG. 4, sealing can be performed with a sealing substrate 1031 provided with colored layers (a red colored layer 1034R, a green colored layer 1034G, and a blue colored layer 1034B). A black matrix 1035 may be provided on the sealing substrate 1031 so as to be located between pixels. The colored layers (the red colored layer 1034R, the green colored layer 1034G, and the blue colored layer 1034B) and the black matrix may be covered with an overcoat layer 1036. Note that a substrate having light transmissivity is used as the sealing substrate 1031. In addition, although an example of full color display using four colors, red, green, blue, and white, is shown here, the present invention is not particularly limited, and full color display using four colors, red, yellow, green, and blue, or three colors, red, green, and blue, may be used.

[0240] In a top-emission type light-emitting device, a microcavity structure can be suitably applied. An EL device having a microcavity structure can be obtained by using a reflective electrode as the anode and a semi-transmissive / semi-reflective electrode as the cathode. At least an EL layer is present between the reflective electrode and the semi-transmissive / semi-reflective electrode, and at least an emitting layer that becomes the light-emitting region is present.

[0241] The reflectance of the reflective electrode to visible light is 40% to 100%, preferably 70% to 100%, and the resistivity is 1×10 -2 The semi-transmitting and semi-reflective electrode has a visible light reflectance of 20% to 80%, preferably 40% to 70%, and a resistivity of 1×10 -2 It is assumed that the film has a resistance of less than Ωcm.

[0242] Light emitted from a light-emitting layer included in the EL layer is reflected by the reflective electrode and the semi-transmissive and semi-reflective electrode, causing resonance.

[0243] In this EL device, the optical distance between the reflective electrode and the semi-transmissive / semi-reflective electrode can be changed by changing the thickness of the transparent conductive film, the above-mentioned composite material, the carrier transport material, etc. This makes it possible to intensify the light of the resonating wavelength between the reflective electrode and the semi-transmissive / semi-reflective electrode and attenuate the light of the non-resonating wavelength.

[0244] In addition, since the light reflected by the reflective electrode and returned (first reflected light) causes significant interference with the light (first incident light) that is directly incident on the semi-transmissive and semi-reflective electrode from the light-emitting layer, it is preferable to adjust the optical distance between the reflective electrode and the light-emitting layer to (2n-1)λ / 4 (where n is a natural number equal to or greater than 1, and λ is the wavelength of the emitted light to be amplified). By adjusting the optical distance, the phase of the first reflected light and the first incident light can be aligned, thereby further amplifying the light emitted from the light-emitting layer.

[0245] In the above configuration, the EL layer may have a structure having multiple light-emitting layers or a structure having a single light-emitting layer. For example, the EL layer may be combined with the above-mentioned tandem EL device configuration, in which multiple EL layers are provided in one EL device with a charge generating layer sandwiched therebetween, and a single or multiple light-emitting layers are formed in each EL layer.

[0246] The microcavity structure makes it possible to increase the emission intensity of a specific wavelength in the front direction, thereby reducing power consumption. In the case of a light-emitting device that displays images using four sub-pixels of red, yellow, green, and blue, in addition to the brightness improvement effect of yellow emission, the microcavity structure that matches the wavelength of each color can be applied to all sub-pixels, resulting in a light-emitting device with good characteristics.

[0247] A light-emitting device with favorable characteristics can be obtained in the light-emitting device of this embodiment because the EL device described in Embodiment 2 is used. Specifically, since the EL device described in Embodiment 2 has favorable luminous efficiency, a light-emitting device with low power consumption can be obtained.

[0248] Up to this point, active matrix type light emitting devices have been described, but from here on, passive matrix type light emitting devices will be described. FIG. 5 shows a passive matrix type light emitting device manufactured by applying the present invention. FIG. 5A is a perspective view showing the light emitting device, and FIG. 5B is a cross-sectional view taken along XY in FIG. 5A. In FIG. 5, an EL layer 955 is provided between an electrode 952 and an electrode 956 on a substrate 951. An end of the electrode 952 is covered with an insulating layer 953. A partition layer 954 is provided on the insulating layer 953. The side walls of the partition layer 954 have an inclination such that the distance between one side wall and the other side wall becomes narrower as the side walls approach the substrate surface. That is, the cross section of the partition layer 954 in the short side direction is trapezoidal, and the bottom side (the side facing the same direction as the surface direction of the insulating layer 953 and in contact with the insulating layer 953) is shorter than the top side (the side facing the same direction as the surface direction of the insulating layer 953 and not in contact with the insulating layer 953). By providing the partition layer 954 in this manner, defects in the EL device due to static electricity or the like can be prevented. In addition, the EL device described in Embodiment 2 is used in a passive matrix light-emitting device, and the light-emitting device can be made to have high reliability or low power consumption.

[0249] The light emitting device described above is capable of individually controlling a large number of minute EL devices arranged in a matrix, and is therefore suitable for use as a display device for displaying images.

[0250] This embodiment mode can be freely combined with other embodiment modes.

[0251] (Embodiment 4) In this embodiment, an example in which the EL device described in Embodiment 2 is used as a lighting device will be described with reference to Fig. 6. Fig. 6B is a top view of the lighting device, and Fig. 6A is a cross-sectional view taken along line ef in Fig. 6B.

[0252] In the lighting device of this embodiment, an anode 401 is formed on a light-transmitting substrate 400 serving as a support. The anode 401 corresponds to the anode 101 in the first embodiment. When light is extracted from the anode 401 side, the anode 401 is formed from a light-transmitting material.

[0253] A pad 412 for supplying a voltage to the cathode 404 is formed on the substrate 400 .

[0254] An EL layer 403 is formed on the anode 401. The EL layer 403 corresponds to the configuration of the EL layer 103 in the embodiment 1, or a combination of the light-emitting units 511 and 512 and the charge generation layer 513. For these configurations, see the description thereof.

[0255] A cathode 404 is formed to cover the EL layer 403. The cathode 404 corresponds to the cathode 102 in the second embodiment. When light is extracted from the anode 401 side, the cathode 404 is formed of a material with high reflectivity. The cathode 404 is connected to a pad 412 to supply a voltage.

[0256] As described above, the lighting device described in this embodiment has an EL device including the anode 401, the EL layer 403, and the cathode 404. Since the EL device has high luminous efficiency, the lighting device in this embodiment can be a lighting device with low power consumption.

[0257] The lighting device is completed by adhering and sealing the substrate 400 on which the EL device having the above-mentioned configuration is formed and the sealing substrate 407 using the sealants 405 and 406. Either the sealant 405 or 406 may be used. Also, a desiccant may be mixed into the inner sealant 406 (not shown in FIG. 6B), which can adsorb moisture and improve reliability.

[0258] Moreover, the pad 412 and a part of the anode 401 can be extended outside the sealing materials 405 and 406 to serve as an external input terminal. Also, an IC chip 420 equipped with a converter or the like may be provided thereon.

[0259] As described above, the lighting device described in this embodiment uses the EL device described in Embodiment 2 as the EL device, and can be a light-emitting device with low power consumption.

[0260] (Embodiment 5) In this embodiment, an example of an electronic device including the EL device described in Embodiment 2 will be described. The EL device described in Embodiment 2 has good luminous efficiency and low power consumption. As a result, the electronic device described in this embodiment can be an electronic device having a light-emitting portion with low power consumption.

[0261] Examples of electronic devices to which the EL devices are applied include television sets (also called televisions or television receivers), computer monitors, digital cameras, digital video cameras, digital photo frames, mobile phones (also called mobile phones or mobile phone devices), portable game machines, personal digital assistants, audio playback devices, large game machines such as pachinko machines, etc. Specific examples of these electronic devices are shown below.

[0262] 7A illustrates an example of a television set. The television set has a display portion 7103 built in a housing 7101. Here, the housing 7101 is supported by a stand 7105. The display portion 7103 can display an image, and is configured such that the EL devices described in Embodiment 2 are arranged in a matrix.

[0263] The television device can be operated using an operation switch provided on the housing 7101 or a separate remote control 7110. Using operation keys 7109 provided on the remote control 7110, the channel and volume can be controlled, and an image displayed on the display portion 7103 can be operated. The remote control 7110 may be provided with a display portion 7107 that displays information output from the remote control 7110.

[0264] The television device is configured to include a receiver, a modem, etc. The receiver can receive general television broadcasts, and by connecting to a wired or wireless communication network via the modem, it is also possible to perform one-way (from sender to receiver) or two-way (between sender and receiver, or between receivers, etc.) information communication.

[0265] FIG. 7B1 shows a computer, which includes a main body 7201, a housing 7202, a display portion 7203, a keyboard 7204, an external connection port 7205, a pointing device 7206, and the like. Note that this computer is manufactured by using the EL devices described in embodiment 2 arranged in a matrix for the display portion 7203. The computer in FIG. 7B1 may have a form as shown in FIG. 7B2. The computer in FIG. 7B2 is provided with a second display portion 7210 instead of the keyboard 7204 and the pointing device 7206. The second display portion 7210 is a touch panel type, and input can be performed by operating the display for input displayed on the second display portion 7210 with a finger or a dedicated pen. The second display portion 7210 can display not only the display for input but also other images. The display portion 7203 may also be a touch panel. The two screens are connected by a hinge, which can prevent the screens from being scratched or damaged during storage or transportation.

[0266] 7C shows an example of a mobile terminal. The mobile phone includes a display portion 7402 built into a housing 7401, operation buttons 7403, an external connection port 7404, a speaker 7405, a microphone 7406, and the like. Note that the mobile phone has the display portion 7402 in which the EL devices described in Embodiment 2 are arranged in a matrix.

[0267] 7C can be configured so that information can be input by touching the display portion 7402 with a finger or the like. In this case, operations such as making a call or composing an e-mail can be performed by touching the display portion 7402 with a finger or the like.

[0268] The screen of the display unit 7402 has three main modes. The first is a display mode that is mainly for displaying images, the second is an input mode that is mainly for inputting information such as characters, and the third is a display + input mode that combines the display mode and the input mode.

[0269] For example, when making a call or composing an e-mail, the display portion 7402 may be set to a character input mode mainly for inputting characters, and the character input operation may be performed by inputting characters displayed on the screen. In this case, it is preferable to display a keyboard or number buttons on most of the screen of the display portion 7402.

[0270] In addition, by providing a detection device having a sensor for detecting tilt, such as a gyro or an acceleration sensor, inside the mobile terminal, the orientation of the mobile terminal (portrait or landscape) can be determined and the screen display of the display portion 7402 can be automatically switched.

[0271] The screen mode can be switched by touching the display portion 7402 or by operating operation buttons 7403 on the housing 7401. The mode can also be switched depending on the type of image displayed on the display portion 7402. For example, if the image signal to be displayed on the display portion is moving image data, the mode is switched to the display mode, and if it is text data, the mode is switched to the input mode.

[0272] In addition, in the input mode, a signal detected by an optical sensor of the display portion 7402 may be detected, and if there is no input by a touch operation on the display portion 7402 for a certain period of time, the screen mode may be controlled to be switched from the input mode to the display mode.

[0273] The display portion 7402 can also function as an image sensor. For example, personal authentication can be performed by touching the display portion 7402 with a palm or a finger to capture an image of a palm print, a fingerprint, or the like. In addition, finger veins, palm veins, or the like can be captured by using a backlight that emits near-infrared light or a sensing light source that emits near-infrared light for the display portion.

[0274] Note that the structure described in this embodiment mode can be used by appropriately combining the structures described in any of Embodiment Modes 1 to 4.

[0275] As described above, the light-emitting device including the EL device described in Embodiment 2 has a very wide range of application, and can be applied to electronic devices in a variety of fields. By using the EL device described in Embodiment 2, electronic devices with low power consumption can be obtained.

[0276] FIG. 8A is a schematic diagram showing an example of a cleaning robot.

[0277] The cleaning robot 5100 has a display 5101 arranged on the top surface, a plurality of cameras 5102 arranged on the side surface, a brush 5103, and an operation button 5104. Although not shown, the bottom surface of the cleaning robot 5100 is provided with tires, a suction port, and the like. The cleaning robot 5100 also has various sensors such as an infrared sensor, an ultrasonic sensor, an acceleration sensor, a piezoelectric sensor, an optical sensor, and a gyro sensor. The cleaning robot 5100 also has wireless communication means.

[0278] The cleaning robot 5100 can move by itself, detect dirt 5120, and suck up the dirt from a suction port provided on the bottom surface.

[0279] In addition, the cleaning robot 5100 can analyze the image captured by the camera 5102 and determine the presence or absence of obstacles such as walls, furniture, steps, etc. Furthermore, when an object that may become entangled in the brush 5103, such as a wire, is detected by image analysis, the rotation of the brush 5103 can be stopped.

[0280] The remaining battery level, the amount of sucked up dirt, etc. can be displayed on the display 5101. The route traveled by the cleaning robot 5100 may be displayed on the display 5101. The display 5101 may be a touch panel, and an operation button 5104 may be provided on the display 5101.

[0281] The cleaning robot 5100 can communicate with a portable electronic device 5140 such as a smartphone. Images captured by the camera 5102 can be displayed on the portable electronic device 5140. Therefore, the owner of the cleaning robot 5100 can know the state of the room even when he or she is away from home. Also, the display on the display 5101 can be confirmed on a portable electronic device such as a smartphone.

[0282] The light-emitting device according to one embodiment of the present invention can be used for the display 5101 .

[0283] The robot 2100 shown in FIG. 8B includes a computing device 2110, an illuminance sensor 2101, a microphone 2102, an upper camera 2103, a speaker 2104, a display 2105, a lower camera 2106, an obstacle sensor 2107, and a movement mechanism 2108.

[0284] The microphone 2102 has a function of detecting the user's voice, environmental sounds, etc. The speaker 2104 has a function of emitting sound. The robot 2100 can communicate with the user using the microphone 2102 and the speaker 2104.

[0285] The display 2105 has a function of displaying various information. The robot 2100 can display information desired by the user on the display 2105. The display 2105 may be equipped with a touch panel. The display 2105 may also be a removable information terminal, and by installing it in a fixed position on the robot 2100, charging and data transfer are possible.

[0286] The upper camera 2103 and the lower camera 2106 have a function of capturing images of the surroundings of the robot 2100. In addition, the obstacle sensor 2107 can detect the presence or absence of an obstacle in the moving direction when the robot 2100 moves forward using the moving mechanism 2108. The robot 2100 can recognize the surrounding environment and move safely using the upper camera 2103, the lower camera 2106, and the obstacle sensor 2107. The light-emitting device of one embodiment of the present invention can be used for the display 2105.

[0287] 8C is a diagram showing an example of a goggle-type display. The goggle-type display includes, for example, a housing 5000, a display unit 5001, a speaker 5003, an LED lamp 5004, a connection terminal 5006, a sensor 5007 (including a function for measuring force, displacement, position, speed, acceleration, angular velocity, rotation speed, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared), a microphone 5008, a display unit 5002, a support unit 5012, and an earphone 5013.

[0288] The light-emitting device of one embodiment of the present invention can be used for the display portion 5001 and the second display portion 5002 .

[0289] 9 shows an example in which the EL device described in Embodiment 2 is used in a desk lamp, which is a lighting device. The desk lamp shown in FIG. 9 has a housing 2001 and a light source 2002, and the lighting device described in Embodiment 3 may be used as the light source 2002.

[0290] FIG. 10 shows an example in which the EL device described in embodiment 2 is used as an indoor lighting device 3001. Since the EL device described in embodiment 2 has high luminous efficiency, it can be used as a lighting device with low power consumption. In addition, since the EL device described in embodiment 2 can be made large, it can be used as a large-area lighting device. In addition, since the EL device described in embodiment 2 is thin, it can be used as a thin lighting device.

[0291] The EL device described in Embodiment 2 can also be mounted on a windshield or dashboard of an automobile. FIG 11 shows an example in which the EL device described in Embodiment 2 is used on a windshield or dashboard of an automobile. Display regions 5200 to 5203 are provided using the EL device described in Embodiment 2.

[0292] A display region 5200 and a display region 5201 are display devices equipped with the EL device described in embodiment 2, which is provided on the windshield of an automobile. The EL device described in embodiment 2 can be a so-called see-through display device, in which the opposite side can be seen through, by fabricating the anode and cathode with light-transmitting electrodes. If the display is in a see-through state, the display device can be installed on the windshield of an automobile without interfering with the view. When a transistor for driving is provided, it is preferable to use a light-transmitting transistor, such as an organic transistor made of an organic semiconductor material or a transistor using an oxide semiconductor.

[0293] A display area 5202 is a display device provided on a pillar and equipped with the EL device described in Embodiment 2. By displaying an image from an imaging means provided on the vehicle body in the display area 5202, the view blocked by the pillar can be complemented. Similarly, a display area 5203 provided on the dashboard can complement the view blocked by the vehicle body by displaying an image from an imaging means provided on the outside of the vehicle, thereby compensating for blind spots and improving safety. By displaying an image to complement the invisible parts, safety can be confirmed more naturally and without discomfort.

[0294] The display area 5203 can also provide various information by displaying navigation information, a speedometer, a tachometer, mileage, a fuel gauge, gear status, air conditioner settings, etc. The display items and layout can be changed as appropriate to suit the user's preferences. This information can also be displayed in the display areas 5200 to 5202. The display areas 5200 to 5203 can also be used as lighting devices.

[0295] 12A and 12B show a foldable mobile information terminal 5150. The foldable mobile information terminal 5150 has a housing 5151, a display area 5152, and a bending portion 5153. Fig. 12A shows the mobile information terminal 5150 in an unfolded state. Fig. 12B shows the mobile information terminal 5150 in a folded state. Although the mobile information terminal 5150 has a large display area 5152, it is compact and highly portable when folded.

[0296] The display area 5152 can be folded in half by the bending portion 5153. The bending portion 5153 is composed of an expandable member and a plurality of support members, and when folding, the expandable member stretches. The bending portion 5153 is folded with a curvature radius of 2 mm or more, preferably 3 mm or more.

[0297] Note that the display region 5152 may be a touch panel (input / output device) equipped with a touch sensor (input device). The light-emitting device of one embodiment of the present invention can be used for the display region 5152.

[0298] 13A to 13C show a foldable mobile information terminal 9310. Fig. 13A shows the mobile information terminal 9310 in an unfolded state. Fig. 13B shows the mobile information terminal 9310 in a state in which it is changing from one of the unfolded state and the folded state to the other. Fig. 13C shows the mobile information terminal 9310 in a folded state. The mobile information terminal 9310 has excellent portability in the folded state, and has excellent viewability of the display due to a seamless, wide display area in the unfolded state.

[0299] The display panel 9311 is supported by three housings 9315 connected by hinges 9313. Note that the display panel 9311 may be a touch panel (input / output device) equipped with a touch sensor (input device). The display panel 9311 can be reversibly transformed from an unfolded state of the mobile information terminal 9310 to a folded state by bending the two housings 9315 via the hinges 9313. The light-emitting device of one embodiment of the present invention can be used for the display panel 9311. EXAMPLES

[0300] <Synthesis Example 1> In this example, a method for synthesizing organic compounds according to one embodiment of the present invention, 10-(2,2',3,3',4',5,5',6,6'-nonafluoro-4-biphenylyl)9,9-diphenyl-9H,10H-acridine (abbreviation: F9BPPad) and 10,10'-(2,2',3,3',5,5',6,6'-octafluorobiphenylene-4,4'-diyl)bis(9,9-diphenyl-9H,10H-acridine) (abbreviation: Pad2F8BP), will be described. The structures of F9BPPad and Pad2F8BP are shown below.

[0301] [ka]

[0302] <Step 1: Synthesis of 10-(2,2',3,3',4',5,5',6,6'-nonafluoro-4-biphenylyl)9,9-diphenyl-9H,10H-acridine and 10,10'-(2,2',3,3',5,5',6,6'-octafluorobiphenylene-4,4'-diyl)bis(9,9-diphenyl-9H,10H-acridine)> 0.41g (16.5mmol) of lithium amide was placed in a three-neck flask, and the flask was once decompressed and replaced with nitrogen. 15mL of dehydrated THF was added to the flask and stirred. 45mL of a THF solution of 5.0g (15mmol) of 9,9-diphenyl-10H-acridine was dropped into the suspension using a syringe. The mixed suspension was stirred at room temperature for about 3 hours and reacted. The mixture was cooled to -78°C. After cooling, 15mL of a THF solution of 5.0g (15mmol) of decafluorobiphenyl was dropped into the mixture using a syringe and reacted for about 2 hours. The mixture was warmed to room temperature and stirred overnight. After stirring, about 50mL of water was added to the mixture and the mixture was separated. The obtained aqueous layer was extracted with ethyl acetate. The organic layer obtained by separation and the ethyl acetate obtained by extraction were mixed, washed with a saturated aqueous sodium bicarbonate solution, and separated. The obtained organic layer was dried using magnesium sulfate, filtered, and the solvent was removed using an evaporator. The obtained mixture was separated and purified by silica gel column chromatography to obtain two types of white solids. One of the two types of white solids obtained was 10-(2,2',3,3',4',5,5',6,6'-nonafluoro-4-biphenylyl)9,9-diphenyl-9H,10H-acridine (abbreviation: F9BPPad) 3.2g (4.95mmol) (yield 33%), and the other was 10,10'-(2,2',3,3',5,5',6,6'-octafluorobiphenylene-4,4'-diyl)bis(9,9-diphenyl-9H,10H-acridine) (abbreviation: Pad2F8BP) 3.1g (3.20mmol), (yield 43%). The synthesis scheme of step 1 is shown below.

[0303] [ka]

[0304] The white solid obtained in step 1 above was analyzed by nuclear magnetic resonance spectroscopy ( 1 H-NMR and 19 The numerical data are shown below. 1 The H-NMR charts are shown in Fig. 14A and Fig. 14B. 19 F-NMR charts of Pad2F8BP are shown in Fig. 15A and Fig. 15B. 1 The H-NMR charts are shown in Fig. 16A and Fig. 16B. 19 The F-NMR charts are shown in Figures 17A and 17B. From these results, it was confirmed that 10-(2,2',3,3',4',5,5',6,6'-nonafluoro-4-biphenylyl)9,9-diphenyl-9H,10H-acridine and 10,10'-(2,2',3,3',5,5',6,6'-octafluorobiphenylene-4,4'-diyl)bis(9,9-diphenyl-9H,10H-acridine) were synthesized by the synthesis method of step 1.

[0305] F9BPPad 1 H-NMR.δ(CDCl 3 ):7.17-7.28(m,8H),6.94-7.04(m,8H),6.48(d,2H,J=7.5Hz). 19 F-NMR.δ(CDCl 3 ):-159.9,-149.3,-141.7,-136.9,-136.3.

[0306] Pad2F8BP 1 H-NMR.δ(CDCl 3 ):7.18-7.29(m,16H),6.95-7.05(m,16H),6.50(d,4H,J=8.0Hz). 19 F-NMR.δ(CDCl 3 ):-141.0,-136.0.

[0307] Next, the obtained solid was purified by train sublimation. Sublimation purification was performed using 3.1 g of F9BP Pad solid at a pressure of 3.0 Pa and an argon flow rate of 17.9 mL / min, and at 195°C. 2.9 g of white crystalline solid was obtained at a recovery rate of 94%. Sublimation purification was performed using 3.0 g of Pad2F8BP solid at a pressure of 3.0 Pa and an argon flow rate of 18.8 mL / min, and at 290°C. 2.6 g of white solid was obtained at a recovery rate of 89%.

[0308] Next, the absorption spectrum and emission spectrum of F9BPPad in a toluene solution are shown in FIG. 19, and the absorption spectrum and emission spectrum of Pad2F8BP in a toluene solution are shown in FIG.

[0309] Next, F9BPPad and Pad2F8BP obtained in this example were analyzed by liquid chromatography mass spectrometry (abbreviation: LC / MS analysis).

[0310] In the LC / MS analysis, LC (liquid chromatography) separation was performed using an Ultimate 3000 manufactured by Thermo Fisher Scientific, and MS analysis (mass spectrometry) was performed using a Q Exactive manufactured by Thermo Fisher Scientific.

[0311] For LC separation, an arbitrary column was used, the column temperature was set to 40° C., and the solvent was appropriately selected as the liquid delivery condition. The sample was prepared by dissolving F9BPPad and Pad2F8BP at arbitrary concentrations in an organic solvent, and the injection volume was set to 5.0 μL.

[0312] By PRM, the MS of m / z=648.13, which is an ion derived from F9BPPad, 2Measurements were performed. The PRM settings were set to a mass range of the target ion of m / z = 648.13 ± 2.0 (isolation window = 4), and detection was performed in positive mode. The energy NCE (Normalized Collision Energy) for accelerating the target ion in the collision cell was set to 20. The obtained MS spectrum is shown in Figure 29.

[0313] By PRM, the MS of m / z=961.28, which is an ion derived from Pad2F8BP, was detected. 2 Measurements were performed. The PRM settings were set to a mass range of the target ion of m / z = 961.28 ± 2.0 (isolation window = 4), and detection was performed in positive mode. The energy NCE (Normalized Collision Energy) for accelerating the target ion in the collision cell was set to 30. The obtained MS spectrum is shown in Figure 30. EXAMPLES

[0314] Example 1 In this example, an EL device according to one embodiment of the present invention described in the embodiment and a comparative EL device will be described. The structural formulae of organic compounds used in this example are shown below.

[0315] [ka]

[0316] (Method of Fabricating EL Device 1-0) First, indium tin oxide containing silicon oxide (ITSO) was formed into a film on a glass substrate by sputtering to form the anode 101. The film thickness was 70 nm, and the electrode area was 2 mm×2 mm.

[0317] Next, as a pretreatment for forming an EL device on the substrate, the substrate surface was washed with water, baked at 200° C. for 1 hour, and then subjected to UV ozone treatment for 370 seconds.

[0318] Then, 10 -4The substrate was introduced into a vacuum deposition apparatus whose inside had been reduced in pressure to about Pa, and vacuum baking was carried out at 170° C. for 30 minutes in a heating chamber in the vacuum deposition apparatus, and then the substrate was allowed to cool for about 30 minutes.

[0319] Next, the substrate on which the anode 101 was formed was fixed to a substrate holder provided in a vacuum deposition apparatus so that the surface on which the anode 101 was formed was facing downward. Then, 10-(2,2',3,3',4',5,5',6,6'-nonafluoro-4-biphenylyl)9,9-diphenyl-9H,10H-acridine (abbreviation: F9BPPad) represented by the above structural formula (100) and molybdenum oxide (VI) were co-deposited on the anode 101 to a thickness of 50 nm in a weight ratio of 2:0.5 (=F9BPPad:MoOx) by a deposition method using resistance heating to form a hole injection layer 111.

[0320] Next, N-(1,1'-biphenyl-4-yl)-9,9-dimethyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9H-fluoren-2-amine (abbreviation: PCBBiF) represented by the above structural formula (i) was evaporated onto the hole injection layer 111 to a thickness of 20 nm to form a hole transport layer 112.

[0321] Next, 2-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II) represented by the above structural formula (ii), PCBBiF, and (acetylacetonato)bis(4,6-diphenylpyrimidinato)iridium(III) (abbreviation: [Ir(dppm) 2 (acac)]) in a weight ratio of 0.7:0.3:0.06 (=2mDBTBPDBq-II:PCBBiF:[Ir(dppm) 2 After co-evaporation of 20 nm to give a ratio of 0.8:0.2:0.06 (=2mDBTBPDBq-II:PCBBiF:[Ir(dppm) 2 The light-emitting layer 113 was formed by co-evaporation to a thickness of 20 nm so as to have a thickness of 20 nm (acac).

[0322] Then, 2mDBTBPDBq-II was evaporated onto the light-emitting layer 113 to a thickness of 30 nm, and then 2,9-bis(naphthalene-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviation: NBPhen) represented by the above structural formula (iv) was evaporated onto the light-emitting layer 113 to a thickness of 10 nm to form the electron-transporting layer 114.

[0323] After forming the electron transport layer 114, lithium fluoride (LiF) was evaporated to a thickness of 1 nm to form the electron injection layer 115, and then aluminum was evaporated to a thickness of 200 nm to form the cathode 102, thereby producing the EL device 1-0 of this example.

[0324] (Method of Fabricating EL Devices 1-1 to 1-3) EL device 1-1 was fabricated in the same manner as EL device 1-0, except that the hole injection layer 111 in EL device 1-0 was formed by co-evaporating F9BPPad and molybdenum oxide (VI) to a thickness of 50 nm so as to give a weight ratio of 2:0.5 (=F9BPPad:molybdenum oxide), and then co-evaporating 4,4',4''-(benzene-1,3,5-triyl)tri(dibenzothiophene) (abbreviation: DBT3P-II) represented by the above structural formula (v) and molybdenum oxide (VI) to a thickness of 5 nm so as to give a weight ratio of 2:0.5 (=DBT3P-II:molybdenum oxide).

[0325] EL device 1-2 was fabricated in the same manner as EL device 1-1, except that the layer formed by co-evaporating DBT3P-II and molybdenum oxide in EL device 1-1 was formed to a thickness of 10 nm.

[0326] EL device 1-3 was fabricated in the same manner as EL device 1-1, except that the layer formed by co-evaporating DBT3P-II and molybdenum oxide in EL device 1-1 was formed to a thickness of 15 nm.

[0327] (Method of Fabricating EL Devices 2-0 to 2-3) EL device 2-0 was fabricated in the same manner as EL device 1-0, except that F9BPPad used in the hole injection layer 111 in EL device 1-0 was changed to 10,10'-(2,2',3,3',5,5',6,6'-octafluorobiphenylene-4,4'-diyl)bis(9,9-diphenyl-9H,10H-acridine) (abbreviation: Pad2F8BP) represented by the above structural formula (200).

[0328] EL device 2-1, EL device 2-2, and EL device 2-3 were prepared by replacing F9BPPad in EL device 1-1, EL device 1-2, and EL device 1-3 with Pad2F8BP, respectively.

[0329] (Method of Fabricating Comparative EL Devices 1-0 to 1-3) Comparative EL device 1-0 was fabricated in the same manner as EL device 1-0, except that F9BPPad used in hole-injection layer 111 in EL device 1-0 was changed to DBT3P-II.

[0330] Comparative EL device 1-1, comparative EL device 1-2, and comparative EL device 1-3 were prepared by replacing F9BPPad in EL device 1-1, EL device 1-2, and EL device 1-3 with DBT3P-II, respectively.

[0331] (Method of Fabricating Comparative EL Devices 2-0 to 2-3) Comparative EL device 2-0 was fabricated in the same manner as EL device 1-0, except that F9BPPad used in the hole injection layer 111 in EL device 1-0 was changed to 4,4,8,8,12,12-hexa-p-tolyl-4H-8H-12H-12C-aza-dibenzo[cd,mn]pyrene (abbreviation: FATPA) represented by the above structural formula (vi).

[0332] Comparative EL device 2-1, comparative EL device 2-2, and comparative EL device 2-3 were prepared by replacing F9BPPad in EL device 1-1, EL device 1-2, and EL device 1-3 with FATPA.

[0333] The element structures of EL devices 1-0 to 1-3, EL devices 2-0 to 2-3, comparative EL devices 1-0 to 1-3, and comparative EL devices 2-0 to 2-3 are summarized in the following table.

[0334] [Table 1]

[0335] These EL devices were sealed with glass substrates in a nitrogen atmosphere glove box to prevent the EL devices from being exposed to the atmosphere (sealing material was applied around the elements, and UV treatment was performed during sealing, followed by heat treatment at 80°C for 1 hour), and then the initial characteristics of these EL devices were measured. Note that no special measures were taken to improve extraction efficiency for the glass substrates on which the EL devices were fabricated.

[0336] FIG. 18 shows the results of measuring the refractive index of a composite material using F9BPPad, Pad2F8BP, DBT3P-II, and FATPA. The refractive index n includes n ordinary, which is the refractive index of ordinary light, n extra-ordinary, which is the refractive index of extraordinary light, and n average, which is the average value of both. In this specification, when the term "refractive index" is used, it may be read as n average if anisotropic analysis is not performed, and as n ordinary if anisotropic analysis is performed. The value obtained by multiplying the value of n ordinary by two and the sum of the value of n extra-ordinary divided by 3 is n average. DBT3P-II is a material that can obtain good characteristics by using it as an electron donor material in the hole injection layer.

[0337] 18, the composite material using F9BPPad and Pad2F8BP has a low refractive index, and the EL device of one embodiment of the present invention has a hole-transport layer formed using the composite material, so that the EL device has a hole-transport layer with a low refractive index. Note that the refractive index of other organic compounds used in the EL device is about 1.70 to 1.90.

[0338] The luminance-current density characteristics of EL device 1-0, EL device 2-0, comparative EL device 1-0, and comparative EL device 2-0 are shown in FIG. 21, their current efficiency-luminance characteristics in FIG. 22, their luminance-voltage characteristics in FIG. 23, their current-voltage characteristics in FIG. 24, their external quantum efficiency-luminance characteristics in FIG. 25, and their emission spectra in FIG. 26.

[0339] In addition, the optical transmittance of EL Devices 1-0 to 1-3, EL Devices 2-0 to 2-3, Comparative EL Devices 1-0 to 1-3, and Comparative EL Devices 2-0 to 2-3 at 1000 cd / m 2 The main characteristics in this region are shown in Table 2. A color luminance meter (Topcon Corporation, BM-5A) was used to measure the luminance and CIE chromaticity, and a multichannel spectrometer (Hamamatsu Photonics KK, PMA-11) was used to measure the emission spectrum.

[0340] [Table 2]

[0341] 21 to 26 show that the EL devices 1-0 and 2-0, which are EL devices according to one embodiment of the present invention, have driving performance similar to that of the comparative EL devices 1-0 and 2-0 and have good emission efficiency.

[0342] In this embodiment, since the EL devices are fabricated using materials with different refractive indices, even if each EL device is formed with the same film thickness, the optical distance between the electrodes will be different. In addition, since it is difficult to precisely control the film thickness when fabricating an EL device by vapor deposition, the element may not be fabricated with the film thickness expected in advance.

[0343] In the EL device of this embodiment, the cathode is aluminum, so the reflection at the cathode is large, and the anode also reflects light to a certain extent due to the difference in refractive index, so that the structure is such that light is amplified or attenuated by interference. In principle, which wavelength of light is interfered with or amplified depends on the optical distance between the electrodes.

[0344] Since a substance has its own emission spectrum, if the light is amplified at a wavelength with high emission intensity, the amplification is efficient and the luminous efficiency is high. On the other hand, if light with a wavelength with low emission intensity is amplified, the efficiency is lower than in the above case. In other words, the luminous efficiency increases or decreases depending on the optical distance between the electrodes.

[0345] As described above, in this embodiment, materials with different refractive indices are used, and precise control of the film thickness is difficult, so that the optical distances between the electrodes are different, and therefore a strict comparison of the luminous efficiency cannot be made in FIG. 25.

[0346] FIG. 27 shows the luminance distribution at 1000 cd / m for EL devices 1-0 to 1-3, EL devices 2-0 to 2-3, comparative EL devices 1-0 to 1-3, and comparative EL devices 2-0 to 2-3. 2 The graph shows the relationship between chromaticity x and external quantum efficiency in the vicinity of the x-axis.

[0347] The horizontal axis represents chromaticity x because, although the interference effect is determined by the optical distance between the electrodes, light that is subjected to the same interference effect using the same luminescent material will have a similar emission spectrum, and therefore light of the same chromaticity is subjected to the same interference effect, and it is possible to consider the optical distance between the electrodes to be the same.

[0348] In other words, by using Figure 27, it is possible to cancel the differences in refractive index of the materials mentioned above and the differences in optical distance resulting from the deposition operation, and to verify the effect of improving luminous efficiency purely by using a layer with a low refractive index.

[0349] 27, EL devices 2-0 to 2-3 using Pad2F8BP and FATPA, which have similar refractive indices, and comparative EL devices 2-0 to 2-3 show similar external quantum efficiency at the same chromaticity. Also, EL devices 1-0 to 1-3 using F9BP Pad, which has a lower refractive index, show higher external quantum efficiency than EL devices 2-0 to 2-3 and comparative EL devices 2-0 to 2-3, and can achieve an efficiency improvement of up to 15% compared to comparative EL devices 1-0 to 1-3 using DBT3P-II, which has a normal refractive index as an organic compound used as an organic compound in EL devices.

[0350] As can be seen from Table 2, the EL device according to one embodiment of the present invention is an EL device that does not experience significant deterioration in the driving voltage and has good driving characteristics.

[0351] 28 shows the change in luminance versus drive time when EL device 1-0, EL device 1-2, EL device 2-0, EL device 2-2, comparative EL device 1-0, comparative EL device 1-2, comparative EL device 2-0, and comparative EL device 2-2 were driven at a constant current of 2 mA. As shown in FIG. 28, there was no significant difference in the change in luminance among the EL devices, and it was found that the EL device of one embodiment of the present invention is an EL device that exhibits good luminous efficiency while maintaining a good lifetime. [Explanation of symbols]

[0352] 101: anode, 102: cathode, 103: EL layer, 111: hole injection layer, 112: hole transport layer, 113: light emitting layer, 114: electron transport layer, 115: electron injection layer, 116: charge generation layer, 117: P-type layer, 118: electron relay layer, 119: electron injection buffer layer, 400: substrate, 401: anode, 403: EL layer, 404: cathode, 405: sealing material, 406: sealing material, 407: sealing substrate, 412: pad, 420: IC chip, 501: anode, 502: cathode, 511: first light emitting unit, 512: second light emitting unit, 513: charge generation layer, 601: driving circuit section ( source line driving circuit), 602: pixel section, 603: driving circuit section (gate line driving circuit), 604: sealing substrate, 605: sealing material, 607: space, 608: wiring, 609: FPC (flexible printed circuit), 610: element substrate, 611: switching FET, 612: current control FET, 613: anode, 614: insulator, 616: EL layer, 617: cathode, 618: EL device, 951: substrate, 952: electrode, 953: insulating layer, 954: partition layer, 955: EL layer, 956: electrode, 1001: substrate, 1002: base insulating film, 1003: gate insulating film, 1 006: gate electrode, 1007: gate electrode, 1008: gate electrode, 1020: first interlayer insulating film, 1021: second interlayer insulating film, 1022: electrode, 1024W: anode, 1024R: anode, 1024G: anode, 1024B: anode, 1025: partition wall, 1028: EL layer, 1029: cathode, 1031: sealing substrate, 1032: sealing material, 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 unit, 1041: drive circuit unit, 1042: peripheral unit, 2001: housing, 2002: light source, 2100: robot, 2110: computing device, 2101: illuminance sensor, 2102: microphone, 2103: upper camera, 2104: speaker, 2105: display, 2106: lower camera, 2107: obstacle sensor, 2108: moving mechanism, 3001: lighting device, 5000: housing, 5001: display unit, 5002: second display unit, 5003: speaker, 5004: LED lamp, 5006: connection terminal, 5007: sensor, 5008: microphone, 5012: support unit,5013: Earphones, 5100: Cleaning robot, 5101: Display, 5102: Camera, 5103: Brush, 5104: Operation button, 5150: Mobile information terminal, 5151: Housing, 5152: Display area, 5153: Bend, 5120: Dust, 5200: Display area, 5201: Display area, 5202: Display area, 5203: Display area, 7101: Housing, 7103: Display unit, 7105: Stand, 7107: Display unit, 7109: Operation key, 71 10: remote control operation device, 7201: main body, 7202: housing, 7203: display unit, 7204: keyboard, 7205: external connection port, 7206: pointing device, 7210: second display unit, 7401: housing, 7402: display unit, 7403: operation button, 7404: external connection port, 7405: speaker, 7406: microphone, 9310: mobile information terminal, 9311: display panel, 9312: display area, 9313: hinge, 9315: housing,

Claims

1. An organic compound represented by the following general formula (G1): 【Chemistry 1】 (However, in the above general formula (G1), R １ ~R ４ and R ７ ~R １０ are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, and a fluorinated alkyl group having 1 to 6 carbon atoms; R ５ and R ６ R are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, a fluorinated alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted phenyl group. １３ is either fluorine or a group represented by the following general formula (g1): 【Chemistry 2】 (However, in the above general formula (g1), R ２１ ~R ２４ and R ２７ ~R ３０ are each independently any one of a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and a fluorinated alkyl group having 1 to 6 carbon atoms, and R 25 and R 26 are each a phenyl group.

2. In claim 1, R １３ is a group represented by general formula (g1).

3. In claim 1, R １３ An organic compound in which the atom is fluorine.

4. An organic compound represented by the following general formula (G2): 【Chemistry 3】 (However, in the above general formula (G2), R １ ~R ４ and R ７ ~R １０ are each independently any one of hydrogen, an alkyl group having 1 to 6 carbon atoms, and a fluorinated alkyl group having 1 to 6 carbon atoms; R ５ and R ６ R are each independently any one of a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a fluorinated alkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted phenyl group. ３３ is either fluorine or a group represented by the following general formula (g1): 【Chemistry 4】 (However, in the above general formula (g1), R ２１ ~R ２４ and R ２７ ~R ３０ are each independently any one of a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, and a fluorinated alkyl group having 1 to 6 carbon atoms, and R 25 and R 26 are each a phenyl group.

5. In claim 4, R ３３ is an organic compound represented by general formula (g1).

6. In claim 4, R ３３ An organic compound in which the atom is fluorine.

7. In any one of claims 1 to 6, R ２１ ~R ２４ and R ２７ ~R ３０ are organic compounds in which each is hydrogen.

8. In any one of claims 1 to 7, R ５ and R ６ are organic compounds in which each is a phenyl group.

9. An organic compound represented by the following structural formula (100) or structural formula (200). 【Chemistry 5】 【Chemistry 6】

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