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

Abstract

Provided is a novel organic compound. In particular, the present invention provides a novel organic compound capable of improving the element characteristics of a light-emitting element. Provided is a novel light-emitting element having low luminous efficiency, high driving voltage, and good reliability. Provided is an organic compound having an amine skeleton and a benzo [b] naphtho [1, 2-d] furan skeleton. Also provided is a light-emitting element containing the organic compound.

Description

This application is a divisional application of the Chinese patent application titled “Organic compounds, light-emitting elements, light-emitting devices, electronic devices and lighting devices” with national application number 201780056372.8 after the PCT international application with international application number PCT / IB2017 / 055296 and international application date September 4, 2017 entered the Chinese stage. Technical Field

[0001] One embodiment of the present invention relates to a novel organic compound. One embodiment of the present invention also relates to an aromatic amine compound having a benzo[b]naphtho[1,2-d]furan skeleton. In addition, one embodiment of the present invention relates to a light-emitting element, a light-emitting device, an electronic device, and a lighting device containing the organic compound.

[0002] Note that one embodiment of the present invention is not limited to the above-mentioned technical field. One embodiment of the present invention relates to an object, a method or a manufacturing method. In addition, the present invention relates to a process, a machine, a product or a composition. In particular, one embodiment of the present invention relates to a semiconductor device, a light-emitting device, a display device, a lighting device, a light-emitting element or a method for manufacturing them. In addition, one embodiment of the present invention relates to a novel method for synthesizing an aromatic amine compound having a benzonaphthofuran skeleton. For this reason, as specific examples of one embodiment of the present invention disclosed in this specification, light-emitting elements, light-emitting devices, electronic devices and lighting devices containing the organic compound and methods for manufacturing them can be cited. Background Art

[0003] The practical application of light-emitting elements (organic EL elements) that include organic compounds and utilize electroluminescence (EL) is very active. In the basic structure of such a light-emitting element, an organic compound layer (electroluminescent (EL) layer) containing a light-emitting material is provided between a pair of electrodes. By applying a voltage to the element, carriers are injected, and light emission can be obtained from the light-emitting material using the recombination energy of the carriers.

[0004] Because this light-emitting element is a self-luminous light-emitting element, it has advantages such as higher visibility and no need for backlight when used in pixels of a display. Therefore, this light-emitting element is suitable for flat-panel display elements. In addition, a display using this light-emitting element can be made thin and light, which is also a great advantage. Furthermore, an extremely high response speed is also one of the characteristics of this light-emitting element.

[0005] In this light-emitting element, light-emitting layers can be formed two-dimensionally in sequence, thereby obtaining planar light emission. This is a feature that is difficult to obtain in point light sources represented by incandescent lamps or LEDs or line light sources represented by fluorescent lamps. In addition, by selecting materials, the light emission of organic compounds can be made to be light emission without ultraviolet light, thereby having a high utilization value as a surface light source that can be applied to lighting, etc.

[0006] As described above, although displays or lighting devices including light-emitting elements are applicable to various electronic devices, research and development of light-emitting elements with better efficiency and element life are increasingly active. In particular, since organic compounds are mainly used for EL layers, organic compounds have a great influence on improving the element characteristics of light-emitting elements. Therefore, many novel organic compounds have been developed.

[0007] The life and characteristics of a light-emitting element including an organic compound are sometimes greatly affected by the characteristics of a hole transport material. In particular, the life and characteristics of the element vary greatly depending on the type of hole transport material.

[0008] As hole transport materials, compounds in which a π-conjugated system is extended throughout the molecule, such as aromatic compounds, are generally used. In particular, aromatic amine compounds are being developed. The properties of hole transport materials in aromatic amine compounds are largely dependent on the aromatic skeleton.

[0009] Although various aromatic amine compounds having an aromatic skeleton have been disclosed, the properties and reliability of light-emitting elements including these compounds have been improved but are still insufficient to meet the high requirements for various properties including efficiency and durability (for example, Patent Document 1). [References] [Patent Document]

[0010] [Patent Document 1] PCT International Publication No. WO2009 / 145016 Summary of the invention

[0011] In view of the above problems, one of the purposes of one embodiment of the present invention is to provide a novel organic compound. In particular, one of the purposes of one embodiment of the present invention is to provide a novel organic compound with hole transport properties. Another purpose of one embodiment of the present invention is to provide a light-emitting element with good life. Another purpose of one embodiment of the present invention is to provide a light-emitting element with good luminous efficiency. Another purpose of one embodiment of the present invention is to provide a light-emitting element with low driving voltage.

[0012] Another object of one embodiment of the present invention is to provide a light emitting element, a light emitting device, and an electronic device each having high reliability. Another object of one embodiment of the present invention is to provide a light emitting element, a light emitting device, and an electronic device each having low power consumption.

[0013] Note that the description of these purposes does not prevent the existence of other purposes. In one embodiment of the present invention, it is not necessary to achieve all of the above purposes. Purposes other than the above can be known and extracted from the description of the specification, drawings, claims, etc.

[0014] One embodiment of the present invention is an aromatic amine compound having two substituted or unsubstituted benzo[b]naphtho[1,2-d]furan skeletons.

[0015] Therefore, one embodiment of the present invention is an organic compound represented by the following general formula (G0).

[0016]

[0017] In the general formula (G0), Ar 1 ,Ar 2 and Ar 3 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 25 carbon atoms, Ar 4 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms, and n, m, and l each independently represent an integer of 0 or 1. 1 and A 2 Each independently represents a group represented by the following general formula (g0) or (g1).

[0018]

[0019] In the general formulas (g0) and (g1), Ar 5 and Ar 6 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 13 carbon atoms. 1 To R 18 Each independently represents any one of hydrogen, a hydrocarbon group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a cyano group, a halogen, a haloalkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms.

[0020] In the above general formulae (g0) and (g1), preferably R 1 To R 18 Each independently represents hydrogen or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 13 carbon atoms.

[0021] In the above general formulae (g0) and (g1), preferably R6 and R 15 Each independently represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 13 carbon atoms.

[0022] Another embodiment of the present invention is an organic compound as follows: A in the general formula (G0) 1 and A 2 Each is independently represented by the following general formula (g0-a) or general formula (g1-a).

[0023]

[0024] In the general formulas (g0-a) and (g1-a), Ar 5 and Ar 6 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 25 carbon atoms, R 1 represents hydrogen or substituted or unsubstituted phenyl.

[0025] Another embodiment of the present invention is an organic compound represented by the following general formula (G1).

[0026]

[0027] In the general formula (G1), Ar 1 ,Ar 2 ,Ar 3 ,Ar 5 and Ar 6 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 25 carbon atoms, Ar 4 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms, and n, m, and l each independently represent an integer of 0 or 1. 1 To R 18 Each independently represents any one of hydrogen, a hydrocarbon group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a cyano group, a halogen, a haloalkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms.

[0028] In the above general formula (G1), preferably R 1 To R 18 Each independently represents hydrogen or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 13 carbon atoms.

[0029] In the above general formula (G1), preferably R 6 and R 15 Each independently represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 13 carbon atoms.

[0030] Another embodiment of the present invention is an organic compound represented by the following general formula (G2).

[0031]

[0032] In the general formula (G2), Ar 1 ,Ar 2 ,Ar 3 ,Ar 5 and Ar 6 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 25 carbon atoms, Ar 4 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms, wherein n, m and l each independently represent an integer of 0 or 1.

[0033] Another embodiment of the present invention is an organic compound represented by the following general formula (G3).

[0034]

[0035] In the general formula (G3), Ar 1 ,Ar 2 and Ar 3 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 25 carbon atoms, Ar 4 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms, wherein n, m and l each independently represent an integer of 0 or 1.

[0036] Another embodiment of the present invention is an organic compound represented by the following general formula (G4).

[0037]

[0038] In the general formula (G4), Ar 1 ,Ar 2 and Ar 3 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 25 carbon atoms, Ar 4 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms, wherein n, m and l each independently represent an integer of 0 or 1.

[0039] Another embodiment of the present invention is an organic compound represented by the following general formula (G5).

[0040]

[0041] In the general formula (G5), n represents an integer of 0 to 3.

[0042] Another embodiment of the present invention is an organic compound represented by any one of the following structural formulas (102), (103), (106) and (117).

[0043]

[0044] Another embodiment of the present invention is a light-emitting element including any of the above-mentioned organic compounds.

[0045] The light-emitting element in the above embodiment includes an EL layer between the anode and the cathode. The EL layer includes at least one of a light-emitting layer, a hole transport layer, a hole injection layer, an electron transport layer, and an electron injection layer. In the above embodiment, the EL layer preferably includes a light-emitting layer and a hole transport layer. The hole transport layer is preferably located between the anode and the light-emitting layer. Note that the EL layer may also include other functional layers.

[0046] In the above embodiment, the light-emitting layer preferably contains a light-emitting material.

[0047] Another embodiment of the present invention is a display device, which includes: a light-emitting element having any one of the above-mentioned structures; and at least one of a color filter and a transistor. Another embodiment of the present invention is an electronic device, which includes: the above-mentioned display device; and at least one of a frame and a touch sensor. Another embodiment of the present invention is a lighting device, which includes: a light-emitting element having any one of the above-mentioned structures; and at least one of a frame and a touch sensor. One embodiment of the present invention includes not only a light-emitting device having a light-emitting element in its scope, but also an electronic device having a light-emitting device. Therefore, the light-emitting device in this specification refers to an image display device or a light source (including a lighting device). The following modules sometimes also include light-emitting elements: a module in which a connector such as a flexible printed circuit (FPC) or a tape carrier package (TCP) is installed in the light-emitting device; a module in which a printed circuit board is provided on the end of the TCP; or a module in which an integrated circuit (IC) is directly mounted on the light-emitting element by a chip on glass (COG) method.

[0048] According to one embodiment of the present invention, a novel organic compound can be provided. In particular, a novel organic compound having hole transport properties can be provided. According to one embodiment of the present invention, a light-emitting element with good life can be provided. According to one embodiment of the present invention, a light-emitting element with good luminous efficiency can be provided. According to one embodiment of the present invention, a light-emitting element with low driving voltage can be provided.

[0049] According to another embodiment of the present invention, a light emitting element and an electronic device each having high reliability can be provided. According to another embodiment of the present invention, a light emitting element and an electronic device each having low power consumption can be provided.

[0050] Note that the description of these effects does not prevent the existence of other effects. It is not necessary to achieve all of the above effects in one embodiment of the present invention. Effects other than the above can be known and extracted from the description of the specification, drawings, claims, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0051] In the attached picture: Figures 1A to 1C is a schematic diagram of a light-emitting element according to one embodiment of the present invention, Figure 1D shows the correlation of the highest occupied molecular orbital (also called HOMO) energy level and the lowest unoccupied molecular orbital (also called LUMO) energy level of the EL layer; Figure 2A and Figure 2B is a schematic diagram of a light-emitting element according to one embodiment of the present invention, Figure 2C shows the correlation of the energy levels of the light-emitting layer; Figure 3 is a schematic diagram of a light-emitting element according to one embodiment of the present invention; Figure 4A and Figure 4B is a schematic diagram of an active matrix light-emitting device according to an embodiment of the present invention; Figure 5A and Figure 5B is a schematic diagram of an active matrix light-emitting device according to an embodiment of the present invention; Figure 6 is a schematic diagram of an active matrix light-emitting device according to an embodiment of the present invention; Fig. 7A , Figure 7B1 and Figure 7B2 is a schematic diagram of a display device according to an embodiment of the present invention; Figure 8 is a circuit diagram of a display device according to one embodiment of the present invention; Fig.9A and Fig. 9B is a circuit diagram and a schematic diagram of a pixel of a display device according to an embodiment of the present invention; Fig.10 is a schematic diagram of a display device according to an embodiment of the present invention; Fig.11 is a schematic diagram of a display device according to an embodiment of the present invention; FIG. 12A to FIG. 12D Figures each showing an electronic device according to an embodiment of the present invention; Fig.13 A diagram showing a light source device according to an embodiment of the present invention; Fig.14 A diagram showing a lighting device according to an embodiment of the present invention; Fig.15A diagram showing a lighting device according to an embodiment of the present invention; Fig.16 A diagram showing a vehicle-mounted display device and a lighting device according to an embodiment of the present invention; Fig.17A and Fig. 17B The NMR spectra of the compounds of the examples are shown; Fig.18A and Fig.18B The NMR spectra of the compounds of the examples are shown; Fig.19 The absorption and emission spectra of the compounds of the examples are shown; Fig. 20 The absorption and emission spectra of the compounds of the examples are shown; Fig.21A and Fig. 21B The NMR spectra of the compounds of the examples are shown; Fig. 22 The absorption and emission spectra of the compounds of the examples are shown; Fig.23 The absorption and emission spectra of the compounds of the examples are shown; Fig.24 The current efficiency-luminance characteristics of the light-emitting element of the embodiment are shown; Fig.25 The luminance-voltage characteristics of the light-emitting element of the embodiment are shown; Fig.26 The external quantum efficiency-luminance characteristics of the light-emitting element of the embodiment are shown; Fig. 27 The electroemission spectrum of the light-emitting element of the embodiment is shown; Fig.28 A reliability test of the light emitting element of the embodiment is shown; Fig.29A and Fig.29B The NMR spectra of the compounds of the examples are shown; Fig.30 The absorption and emission spectra of the compounds of the examples are shown; Fig.31 The absorption and emission spectra of the compounds of the examples are shown; Fig.32 The current efficiency-luminance characteristics of the light-emitting element of the embodiment are shown; Fig.33 The current density-voltage characteristics of the light-emitting element of the embodiment are shown; Fig.34 The external quantum efficiency-luminance characteristics of the light-emitting element of the embodiment are shown; Fig.35 The electroemission spectrum of the light-emitting element of the embodiment is shown; Fig.36 The reliability test of the light emitting element of the embodiment is shown. DETAILED DESCRIPTION

[0052] The embodiments of the present invention are described below with reference to the accompanying drawings. However, those skilled in the art can easily understand that the methods and details disclosed herein can be transformed into various forms without departing from the purpose and scope of the present invention. Therefore, the present invention should not be interpreted as being limited to the contents described in the embodiments.

[0053] Note that in each of the drawings described in this specification, the size or thickness of the anode, EL layer, intermediate layer, cathode, etc. may be exaggerated for convenience of description. Therefore, the size of each component is not limited to the size shown in the drawings, and the relative size of each component is not limited.

[0054] Note that, in this specification, etc., for the sake of convenience, ordinal numbers such as "first", "second", and "third" are added, but they do not indicate the order of processes or the upper and lower positional relationship, etc. Therefore, for example, "first" can be appropriately replaced with "second" or "third" to explain. In addition, sometimes the ordinal numbers recorded in this specification, etc. are inconsistent with the ordinal numbers used to specify an embodiment of the present invention.

[0055] In the configuration of the present invention described in this specification, the same reference numerals are used in common between different drawings to represent the same parts or parts having the same function, and their repeated descriptions are omitted. In addition, the same hatching is sometimes used to represent parts having the same function without adding a reference numeral in particular.

[0056] In this specification, color is composed of hue (equivalent to the wavelength of monochromatic light), chroma (chroma, In this specification, the color may be defined by only one or two of the above three elements. In this specification, the case where the colors of two lights are different refers to the case where at least one of the above three elements is different, and also includes the case where the shapes of the spectra of the two lights or the distribution of the relative intensity ratios of each peak are different.

[0057] Note that the terms "film" and "layer" may be interchanged depending on the situation or state. For example, the term "conductive layer" may be interchanged with the term "conductive film". Alternatively, the term "insulating film" may be interchanged with the term "insulating layer".

[0058] (Implementation Method 1) In this embodiment, for example, an organic compound which is one embodiment of the present invention is described below.

[0059] The organic compound according to one embodiment of the present invention is represented by the following general formula (G0).

[0060]

[0061] In the general formula (G0), Ar 1 ,Ar 2 ,Ar 3 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 25 carbon atoms, Ar 4 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms, and n, m, and l each independently represent an integer of 0 or 1. 1 and A 2 Each independently represents a group represented by the following general formula (g0) or (g1).

[0062]

[0063] In the general formulas (g0) and (g1), Ar 5 and Ar 6 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 13 carbon atoms. 1 To R 18 Each independently represents any one of hydrogen, a hydrocarbon group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a cyano group, a halogen, a haloalkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms.

[0064] Another embodiment of the present invention is an organic compound as follows: R in the general formula (g0) and (g1) 1 To R 18 Each independently represents hydrogen or a substituted or unsubstituted aromatic hydrocarbon group having 6 to 13 carbon atoms.

[0065] Another embodiment of the present invention is an organic compound as follows: R in the general formula (g0) and (g1) 6 and R 15 Each independently represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 13 carbon atoms.

[0066] Another embodiment of the present invention is an organic compound as follows: A in the general formula (G0) 1 and A 2 Each is independently represented by the following general formula (g0-a) or (g1-a).

[0067]

[0068] In the general formulas (g0-a) and (g1-a), Ar 5 and Ar6 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 25 carbon atoms, R 1 represents hydrogen or substituted or unsubstituted phenyl.

[0069] Another embodiment of the present invention is an organic compound represented by the general formula (G1). In the organic compound, the distribution of the π conjugated system extends to the bulky substituent benzo[b]naphtho[1,2-d]furan skeleton in the organic compound, thereby obtaining high carrier transport properties. By having the above structure, the organic compound can have a high T1 energy level.

[0070]

[0071] In the general formula (G1), Ar 1 ,Ar 2 ,Ar 3 ,Ar 5 and Ar 6 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 25 carbon atoms, Ar 4 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms, and n, m, and l each independently represent an integer of 0 or 1. 1 To R 18 Each independently represents any one of hydrogen, a hydrocarbon group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a cyano group, a halogen, a haloalkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms.

[0072] Another embodiment of the present invention is an organic compound represented by the general formula (G2). In the organic compound, the distribution of the π conjugated system extends to the benzo[b]naphtho[1,2-d]furan skeleton, so the organic compound can have high carrier transport properties. By having the above structure, the organic compound can have a high T1 energy level.

[0073]

[0074] In the general formula (G2), Ar 1 ,Ar 2 ,Ar 3 ,Ar 5 and Ar 6 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 25 carbon atoms, Ar 4 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms, wherein n, m and l each independently represent an integer of 0 or 1.

[0075] Another embodiment of the present invention is an organic compound represented by the general formula (G3). In the organic compound, the distribution of the π conjugated system extends to the large substituent benzo[b]naphtho[1,2-d]furan skeleton in the organic compound, thereby obtaining high carrier transport properties. In addition, in the organic compound represented by the general formula (G3), the amino group is bonded to the 8th position of the benzo[b]naphtho[1,2-d]furan skeleton through a phenylene group, thereby expanding the π conjugation, thereby having a high T1 energy level.

[0076]

[0077] In the general formula (G3), Ar 1 ,Ar 2 and Ar 3 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 25 carbon atoms, Ar 4 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms, wherein n, m and l each independently represent an integer of 0 or 1.

[0078] Another embodiment of the present invention is an organic compound represented by the general formula (G4). In the organic compound, the distribution of the π conjugated system extends to the large substituent benzo[b]naphtho[1,2-d]furan skeleton in the organic compound, thereby obtaining high carrier transport properties. In addition, in the organic compound represented by the general formula (G4), the amino group is bonded to the 8th position of the benzo[b]naphtho[1,2-d]furan skeleton through a phenylene group, thereby expanding the π conjugation, thereby obtaining a high T1 energy level.

[0079]

[0080] In the general formula (G4), Ar 1 ,Ar 2 ,Ar 3 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 25 carbon atoms, Ar 4 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms, wherein n, m and l each independently represent an integer of 0 or 1.

[0081] Another embodiment of the present invention is an organic compound represented by the general formula (G5). In the organic compound, the distribution of the π conjugated system extends to the large substituent benzo[b]naphtho[1,2-d]furan skeleton in the organic compound, thereby obtaining high carrier transport properties. In the organic compound represented by the general formula (G5), the amino group is bonded to the 8th position of the benzo[b]naphtho[1,2-d]furan skeleton through a phenylene group, and the π conjugation is expanded, thereby obtaining a high T1 energy level of the organic compound.

[0082]

[0083] Note that in the general formula (G5), n represents an integer of 0 to 3.

[0084] Another embodiment of the present invention is an organic compound represented by any one of the following structural formulas (102), (103), (106) and (117).

[0085]

[0086] <Examples of Substituents> In the general formulae (G0) to (G4) and (g0) to (g1), as Ar 1 ,Ar 2 ,Ar 3 ,Ar 5 and Ar 6 The aromatic hydrocarbon-diyl represented by can be exemplified by phenylene, naphthylene, biphenyl diyl, 9H-fluorene-diyl, 9,9'-spirobi[9H-fluorene]-diyl. Specifically, the groups represented by the following structural formulas (Ar-1) to (Ar-18) can be used. Note that the groups represented by Ar 1 ,Ar 2 ,Ar 3 ,Ar 5 ,Ar 6 The groups represented are not limited thereto, and may have a substituent.

[0087]

[0088] In the general formulae (G0) to (G4) and (g0) to (g1), as Ar 4 Examples of aromatic hydrocarbon groups represented by include phenyl, naphthyl, and substituents combining phenyl and naphthyl. Specifically, groups represented by the following structural formulas (Ar-19) to (Ar-31) can be used. 4 The groups represented are not limited thereto, and may have a substituent.

[0089]

[0090] In the general formulas (G0), (g0), and (g1), as R 1 To R 18 Examples of the group represented by hydrogen, a hydrocarbon group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a cyano group, a halogen, a haloalkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms include groups represented by the following structural formulas (R-1) to (R-57). Note that R 1 To R 18The basis represented is not limited thereto.

[0091] When Ar 1 To Ar 6 and R 1 To R 18 When there is a substituent, examples of the substituent include groups represented by the following structural formulae (R-1) to (R-57), but the substituent is not limited thereto.

[0092]

[0093]

[0094] <Specific Examples of Compounds> Specific structures of the compounds represented by general formulae (G0) to (G4) include compounds represented by the following structural formulae (101) to (152). Note that the compounds represented by general formulae (G0) to (G4) are not limited to the following examples.

[0095]

[0096]

[0097]

[0098]

[0099]

[0100]

[0101]

[0102]

[0103]

[0104]

[0105]

[0106] In the organic compound of one embodiment of the present invention, the distribution of the π conjugated system extends to the large substituent benzo[b]naphtho[1,2-d]furan skeleton in the organic compound and has high carrier transport properties. Therefore, the light-emitting element including the organic compound can be driven at a low voltage. In addition, since the band gap of the organic compound is wide, the light-emitting element including the organic compound can have high luminous efficiency.

[0107] The life of a light-emitting element including an organic compound is sometimes affected by the characteristics of a hole transport material. In particular, the transport property of the hole transport material has a great influence on the life of the element, and this greatly varies depending on the type of the hole transport material.

[0108] As hole transport materials, compounds whose π conjugated systems are extended over a wide range of molecules, represented by aromatic compounds, are generally used. A typical example of such compounds is an aromatic amine compound. Generally, an aromatic amine compound having a π conjugated system has a negatively charged portion in the molecule, so the aromatic amine compound has good hole transport properties and can be suitably used as a hole transport material. In recent years, a variety of aromatic amine compounds have been developed.

[0109] Note that the redox properties of aromatic amine compounds, the distribution of the π-conjugated system, and the charge density depend on the properties of the aromatic skeleton and the bonding position between the aromatic skeleton and the amine skeleton. Therefore, the selection of the aromatic skeleton and the bonding position is crucial for the development of hole transport materials.

[0110] The present inventors have found that an aromatic amine compound having two benzo[b]naphtho[1,2-d]furan skeletons has a high hole-transporting property and that the life of a light-emitting element using the organic compound for a hole-transporting layer is improved.

[0111] The benzonaphthofuran skeleton is preferably a benzo[b]naphtho[1,2-d]furan skeleton, because the benzonaphthofuran can be synthesized and purified more simply at lower cost.

[0112] In particular, an organic compound having two benzo[b]naphtho[1,2-d]furan skeletons bonded to an arylene group at the 8th position or the 6th position in one molecule and the benzo[b]naphtho[1,2-d]furan skeletons are bonded to an amine skeleton via the arylene group, respectively, in one molecule is preferred. More preferred is an organic compound having two benzo[b]naphtho[1,2-d]furan skeletons bonded to an arylene group at the 8th position in one molecule and the benzo[b]naphtho[1,2-d]furan skeletons are bonded to an amine skeleton via the arylene group, respectively, in one molecule is preferred.

[0113] By adopting the above structure, the distribution of the π-conjugated system is extended to the bulky substituted benzo[b]naphtho[1,2-d]furan skeleton, so that the organic compound has high carrier transport properties, and the light-emitting element using the organic compound can be driven at a low voltage.

[0114] Generally, the HOMO energy level of an organic compound having a triphenylamine skeleton is about -5.3 eV, while the HOMO energy level of an organic compound having two benzo[b]naphtho[1,2-d]furan skeletons bonded to an arylene group at the 8th position in one molecule and the benzo[b]naphtho[1,2-d]furan skeletons bonded to an amine skeleton via the arylene group is about -5.5 eV. This is because the HOMO distribution of the organic compound having the above structure is wider than that of the organic compound having a general triphenylamine skeleton.

[0115] As described above, the HOMO energy level of an organic compound having two benzo[b]naphtho[1,2-d]furan skeletons bonded to an arylene group at the 8th position in one molecule and the benzo[b]naphtho[1,2-d]furan skeletons bonded to an amine skeleton via the arylene group is lower than the HOMO energy level of an organic compound having a general triphenylamine skeleton. Therefore, when the organic compound of one embodiment of the present invention is used for a hole transport layer of a light-emitting element, the hole injection barrier between the light-emitting layer and the hole transport layer is reduced, and the driving voltage of the light-emitting element can be reduced, so it is preferred.

[0116] It is preferable to bond the arylene group to the benzo[b]naphtho[1,2-d]furan skeleton at the 8th position because the organic compound of one embodiment of the present invention can have a high T1 level.

[0117] When the arylene group connecting the nitrogen atom and the benzo[b]naphtho[1,2-d]furan skeleton is a phenylene group, the nitrogen atom and the benzo[b]naphtho[1,2-d]furan skeleton are preferably bonded at the para position relative to the phenylene group. By adopting the above structure, the distribution of the π conjugated system is extended to the bulky substituent benzo[b]naphtho[1,2-d]furan skeleton, so the organic compound of one embodiment of the present invention has high carrier transport properties.

[0118] As described above, the organic compound of one embodiment of the present invention is an aromatic amine compound and has high hole transport properties. In addition, since the organic compound of one embodiment of the present invention has a wide band gap, a light-emitting element including the organic compound can have high luminous efficiency. The light-emitting element including the organic compound in the hole transport layer has a higher recombination probability (carrier balance) of holes and electrons in the EL layer and can suppress the diffusion of excitons from the light-emitting layer, so a light-emitting element with high luminous efficiency and long element life can be provided.

[0119] Therefore, the organic compound of one embodiment of the present invention is suitable as a material for a hole transport layer of a light-emitting element. In addition, the organic compound can also be used as a host material in a light-emitting layer.

[0120] One of the important properties that organic compounds used in light-emitting elements need to have is heat resistance. When the glass transition temperature (Tg) of the material is used as an indicator, it can be considered that the higher the Tg, the better the heat resistance. Generally speaking, materials with large molecular weight tend to have higher Tg. Therefore, in order to improve the heat resistance of the material, it is necessary to increase the molecular weight.

[0121] The molecular weight of an organic compound can be increased by, for example, introducing aromatic hydrocarbon groups such as phenyl or naphthyl or increasing the number of aromatic condensed rings. However, the above method may cause problems such as a decrease in the T1 energy level of the organic compound and a decrease in carrier transport properties depending on the bonding position of the substituent.

[0122] Although the organic compound of one embodiment of the present invention includes a plurality of aromatic hydrocarbon groups and a benzo[b]naphtho[1,2-d]furan skeleton having a condensed ring structure in the molecule and a large molecular weight, the organic compound has high carrier transport properties and a high T1 energy level.

[0123] In order to obtain the above-mentioned characteristics, it is preferred to have a structure in which two benzo[b]naphtho[1,2-d]furan skeletons are bonded to an arylene group at the 8th position or the 6th position in one molecule, and the benzo[b]naphtho[1,2-d]furan skeletons are bonded to an amine skeleton via the arylene group. It is more preferred to have a structure in which two benzo[b]naphtho[1,2-d]furan skeletons are bonded to an arylene group at the 8th position in one molecule, and the benzo[b]naphtho[1,2-d]furan skeletons are bonded to an amine skeleton via the arylene group.

[0124] Note that when the benzo[b]naphtho[1,2-d]furan skeleton bonded to the arylene group at the 8th position has a substituent, the substituent is preferably bonded to the 6th position. When the substituent is bonded to the 6th position of the benzo[b]naphtho[1,2-d]furan skeleton, the molecular weight can be increased without reducing the carrier transport property and the T1 level.

[0125] Note that generally, organic compounds have a tendency to have a higher glass transition temperature (Tg) as their molecular weight increases. However, due to the improvement of heat resistance, the sublimation temperature or boiling point in the sublimation purification or distillation performed in the purification process also tends to become higher. When only the molecular weight is increased, the sublimation temperature or boiling point also increases. As a result, a higher temperature is required in the film forming process such as evaporation or the purification process such as sublimation purification and distillation, which may cause the decomposition of the organic compound.

[0126] That is, if the molecular weight is simply increased in order to improve the thermal properties of an organic compound, the possibility of decomposition in a purification step or a film formation step increases, and therefore it may be difficult to use a highly purified organic compound in a device.

[0127] However, the organic compound of one embodiment of the present invention has a structure in which two benzo[b]naphtho[1,2-d]furan skeletons are bonded to an arylene group at the 8th or 6th position in one molecule, and the benzo[b]naphtho[1,2-d]furan skeletons are bonded to an amine skeleton via the arylene group, respectively. Therefore, although the molecular weight is large, the decomposition temperature is high. Therefore, it is not easy to decompose in the purification process or the vapor deposition process, and the material with high purity can be used for the element. In other words, a component with high heat resistance and good characteristics can be provided.

[0128] The film of the organic compound according to one embodiment of the present invention can be formed by a method such as a vapor deposition method (including a vacuum vapor deposition method), an inkjet method, a coating method, or a gravure printing method.

[0129] This embodiment mode can be combined with any other embodiment mode as appropriate.

[0130] (Implementation Method 2) In this embodiment, a method for synthesizing an organic compound represented by the general formula (G0) according to one embodiment of the present invention is described.

[0131]

[0132] In the general formula (G0), Ar 1 ,Ar 2 ,Ar 3 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 25 carbon atoms, Ar 4 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms, and n, m, and l each independently represent an integer of 0 or 1. 1 and A 2 Each independently represents a group represented by the following general formula (g0) or (g1).

[0133]

[0134] In the general formulas (g0) and (g1), Ar 5 and Ar 6 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 13 carbon atoms. 1 To R 18 Each independently represents any one of hydrogen, a hydrocarbon group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a cyano group, a halogen, a haloalkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms. This organic compound is useful from the viewpoint of ease of synthesis and synthesis cost.

[0135] When A of the organic compound represented by the general formula (G0) according to one embodiment of the present invention is 1 and A 2 When they have the same structure, they can be synthesized by the following synthesis scheme (a-1). That is, by coupling an aromatic amine compound (Compound 1) with a compound having a benzo[b]naphtho[1,2-d]furanyl group (Compound 2), the target compound (G0-a) can be obtained. The synthesis scheme (a-1) is shown below.

[0136]

[0137] In the synthesis scheme (a-1), Ar 1 To Ar 3 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 25 carbon atoms, Ar 4 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms, n, m, and l each independently represent an integer of 0 or 1, and X 1 represents chloro, bromo, iodo, or trifluoromethanesulfonate. 1 It is a group represented by the following general formula (g0) or (g1).

[0138]

[0139] In the general formulas (g0) and (g1), Ar 5 and Ar 6 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 13 carbon atoms. 1 To R 18 Each independently represents any one of hydrogen, a hydrocarbon group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a cyano group, a halogen, a haloalkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms.

[0140] In the synthesis scheme (a-1), a Buchwald-Hartwig reaction using a palladium catalyst can be performed. When performing this reaction, bis(dibenzylideneacetone)palladium(0), palladium acetate, (II), [1,1-bis(diphenylphosphino)ferrocene]dichloropalladium(II), tetrakis(triphenylphosphine)palladium(0), allylpalladium(II) chloride dimer and other palladium compounds, tri(tert-butyl)phosphine, tri(n-hexyl)phosphine, tricyclohexylphosphine, di(1-adamantyl)-n-butylphosphine, 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl, tri(o-tolyl)phosphine, (S)-(6,6'-dimethoxybiphenyl-2,2'-diyl)bis(diisopropylphosphine) (abbreviation: cBRIDP (registered trademark)) and other ligands. In this reaction, organic bases such as sodium tert-butoxide and inorganic bases such as potassium carbonate, cesium carbonate, sodium carbonate and the like can be used. In addition, in this reaction, toluene, xylene, benzene, tetrahydrofuran, dioxane and the like can be used as solvents. The reagents that can be used in this reaction are not limited to the above reagents.

[0141] When the Ullmann reaction is carried out in the synthesis scheme (a-1), copper or copper compounds can be mentioned as reagents that can be used, and inorganic bases such as potassium carbonate can be mentioned as bases. As solvents that can be used in this reaction, 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)pyrimidone (DMPU), toluene, xylene, benzene, etc. can be mentioned. In the Ullmann reaction, when the reaction temperature is above 100°C, the target product can be obtained in a shorter time and with a high yield, so it is preferred to use DMPU and xylene with a high boiling point. The reaction temperature is more preferably a high temperature of more than 150°C, so it is more preferred to use DMPU. The reagents that can be applied to this reaction are not limited to the above reagents.

[0142] When A of the organic compound represented by the general formula (G0) according to one embodiment of the present invention is 1 and A 2 When the structures of are different, the following synthesis schemes (b-1) and (b-2) can be used to make A 1 or A 2 The compound with the skeleton (Compound 2 or Compound 4) is synthesized by reacting it twice. 1 and A 2 of compounds with different structures.

[0143]

[0144]

[0145] In the synthesis schemes (b-1) and (b-2), Ar 1 To Ar 3 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 25 carbon atoms, Ar 4represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms, n, m, and l each independently represent an integer of 0 or 1, and X 1 and X 2 Each independently represents chlorine, bromine, iodine, or trifluoromethanesulfonate. 1 and A 2 Each represents a group represented by the following general formula (g0) or (g1).

[0146]

[0147] In the general formulas (g0) and (g1), Ar 5 and Ar 6 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 13 carbon atoms. 1 To R 18 Each independently represents any one of hydrogen, a hydrocarbon group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a cyano group, a halogen, a haloalkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms.

[0148] In the above-mentioned synthesis schemes (b-1) and (b-2), the Buchwald-Hartwig reaction or the Ullmann reaction can be carried out. The reagents that can be used in each reaction are the same as those in the synthesis scheme (a-1).

[0149] Different synthesis methods of an organic compound represented by the general formula (G0) according to one embodiment of the present invention are described. The synthesis method for performing an amination reaction is described above, and here, the synthesis method using a triarylamine compound as a raw material is described. The target compound (G0-b) can be obtained by coupling the triaryl compound (compound 5) with a benzo[b]naphtho[1,2-d]furan compound (compound 6) in an amount of 2 equivalents relative to compound 5.

[0150]

[0151] In the synthesis scheme (c-1), Ar 1 To Ar 3 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 25 carbon atoms, Ar 4 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms, n, m, and l each independently represent an integer of 0 or 1, and X 3 To X 5 represents a halogen group, a boronic acid group, an organic boron group or a trifluoromethanesulfonate group. 1 It represents a group represented by the following general formula (g0-1) or (g1-1).

[0152]

[0153] In the general formulas (g0-1) and (g1-1), R 1 To R 18 Each independently represents any one of hydrogen, a hydrocarbon group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a cyano group, a halogen, a haloalkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms.

[0154] In the synthesis scheme (c-1), when the Suzuki-Miyaura coupling reaction using a palladium catalyst is carried out, X 3 To X 5 Each independently represents a halogen, a boronic acid group, an organic boron group or a trifluoromethylsulfonyl group, and the halogen is preferably iodine, bromine or chlorine. In this reaction, bis(dibenzylideneacetone)palladium can be used. (0), palladium acetate (II), [1,1-bis (diphenylphosphino) ferrocene] dichloropalladium (II), tetrakis (triphenylphosphine) palladium (0) and other palladium compounds, tri (tert-butyl) phosphine, tri (n-hexyl) phosphine, tricyclohexyl phosphine, di (1-adamantyl) -n-butyl phosphine, 2-dicyclohexylphosphino-2',6'-dimethoxybiphenyl, tri (o-tolyl) phosphine and other ligands. In this reaction, organic bases such as sodium tert-butoxide and inorganic bases such as potassium carbonate, cesium carbonate, sodium carbonate and the like can be used. In addition, in this reaction, toluene, xylene, benzene, tetrahydrofuran, dioxane, ethanol, methanol, water and the like can be used as solvents. The reagents that can be used for this reaction are not limited to the above reagents.

[0155] The reaction performed in the synthesis scheme (c-1) is not limited to the Suzuki-Miyaura coupling reaction, and the Ueda-Kosugi-Stille coupling reaction using an organic tin compound, the Kumada-Tamao-Corriu coupling reaction using a Grignard reagent, the Negishi coupling reaction using an organic zinc compound, the reaction using copper or a copper compound, etc. can also be used. When the Ueda-Kosugi-Stille coupling reaction is used, when X 3 and X 4 When each represents an organotin group, X 5 represents a halogen, and vice versa. That is, one of compound 5 and compound 6 is an organotin compound and the other is a halide. When the Kumada-Tamo-Corriu coupling reaction is used, when X 3 and X 4 When each represents a magnesium halide 5 represents a halogen, and vice versa. That is, one of compound 5 and compound 6 is a Grignard reagent and the other is a halide. When using the Negishi coupling reaction, when X 3 and X 4 When each represents an organic zinc group, X5 represents a halogen, and vice versa. That is, one of Compound 5 and Compound 6 is an organozinc compound, and the other is a halide.

[0156] When A of the organic compound represented by the general formula (G0) according to one embodiment of the present invention is 1 and A 2 When the structures of are different, the following synthesis schemes (d-1) and (d-2) can be used to make a 1 or a 2 The compound of the skeleton (compound 6 or compound 8) is synthesized by reacting it twice. By reacting it twice, A 1 and A 2 of compounds with different structures.

[0157]

[0158]

[0159] In the synthesis schemes (d-1) and (d-2), Ar 1 To Ar 3 Each independently represents a substituted or unsubstituted aromatic hydrocarbon-diyl group having 6 to 25 carbon atoms, Ar 4 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms, n, m, and l each independently represent an integer of 0 or 1, and X 3 To X 6 represents a halogen group, a boronic acid group, an organic boron group or a trifluoromethanesulfonate group. 1 and a 2 Each is a group represented by the following general formula (g0-1) or (g1-1).

[0160]

[0161] In the general formulas (g0-1) and (g1-1), R 1 To R 18 Each independently represents any one of hydrogen, a hydrocarbon group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a cyano group, a halogen, a haloalkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms.

[0162] In the synthesis schemes (d-1) and (d-2), the Suzuki-Miyaura coupling reaction, the Ueda-Kosugi-Stille coupling reaction, the Kumada-Tamao-Corriu coupling reaction using a Grignard reagent, the Negishi coupling reaction using an organic zinc compound, the reaction using copper or a copper compound, etc. can be utilized in the same manner as in the above-mentioned synthesis scheme (c-1). When the Ueda-Kosugi-Stille coupling reaction is used, when X3 and X 4 When each represents an organotin group, X 5 and X 6 Each represents a halogen, and vice versa. That is, one of compound 5 and compound 6 is an organotin compound, and the other is a halide. In addition, one of compound 7 and compound 8 is an organotin compound, and the other is a halide. When the Kumada-Tamo-Corriu coupling reaction is used, when X 3 and X 4 When each represents a magnesium halide 5 and X 6 Each represents a halogen, and vice versa. That is, one of compound 5 and compound 6 is a Grignard reagent, and the other is a halide. In addition, one of compound 7 and compound 8 is a Grignard reagent, and the other is a halide. When using the Negishi coupling reaction, when X 3 and X 4 When each represents an organic zinc group, X 5 and X 6 Each represents a halogen, and vice versa. That is, one of compound 5 and compound 6 is an organic zinc compound, and the other is a halide. In addition, one of compound 7 and compound 8 is an organic zinc compound, and the other is a halide.

[0163] Note that the synthesis method of the organic compound represented by the general formula (G0) according to one embodiment of the present invention is not limited to the synthesis schemes (a-1) to (d-2).

[0164] (Implementation 3) In this embodiment, refer to Figures 1A to 1D and FIG. 2A to FIG. 2C A structural example of a light-emitting element including the organic compound according to one embodiment of the present invention is described.

[0165] Figure 1A 1 is a cross-sectional view of a light-emitting element 100 according to one embodiment of the present invention. The light-emitting element 100 includes at least a pair of electrodes (electrode 101 and electrode 102) and an EL layer 103 provided between the pair of electrodes.

[0166] The EL layer 103 includes at least a light-emitting layer 113 and a hole-transporting layer 112. The EL layer 103 also includes functional layers such as a hole-injecting layer 111, an electron-transporting layer 114, and an electron-injecting layer 115.

[0167] Although the case where the electrode 101 is used as an anode and the electrode 102 is used as a cathode is described in this embodiment, the structure of the light-emitting element is not limited to this. That is, a structure where the electrode 101 is used as a cathode and the electrode 102 is used as an anode may also be used. In this case, the stacking order is reversed. That is, the hole injection layer, the hole transport layer, the light-emitting layer, the electron transport layer, and the electron injection layer are stacked in sequence from the anode side.

[0168] The structure of the EL layer 103 is not limited thereto, and the EL layer 103 may include a functional layer that can enhance or inhibit the transport of electrons or holes or suppress the diffusion of excitons. Each of the functional layers may be a single layer or a stacked layer.

[0169] In the light-emitting element 100 , at least one layer of the EL layer 103 contains the organic compound of one embodiment of the present invention. Note that the organic compound is preferably contained in the light-emitting layer 113 , and more preferably contained in the hole-transport layer 112 .

[0170] When the organic compound according to one embodiment of the present invention is included in the light-emitting layer 113 , the organic compound can be used as a host material because the organic compound has a high hole-transport property and a wide band gap.

[0171] When the organic compound of one embodiment of the present invention is included in the hole transport layer 112, since the organic compound has high hole transport properties and a wide band gap, a light-emitting element with high luminous efficiency and long element life can be provided. In particular, the organic compound is suitable for the following case: the hole injection layer 111 is provided between the hole transport layer 112 and the electrode 101 and includes an organic compound having an acceptor property that is easy to inject holes from the electrode.

[0172] <Structural Example 1 of Light Emitting Element> When hole injection is performed using an organic compound having an acceptor property, the compound contained in the hole transport layer 112 in contact with the hole injection layer 111 makes it easier to extract electrons from the organic compound having an acceptor property, so it is preferably a hole transport material with a relatively high HOMO energy level. However, hole transport materials with a high HOMO energy level are difficult to inject holes into the light-emitting layer 113. When the light-emitting layer 113 is formed in a manner that contacts the hole transport layer 112 composed of the hole transport material with a high HOMO energy level, carriers accumulate at the interface between the hole transport layer 112 and the light-emitting layer 113, which may lead to a decrease in the life and efficiency of the light-emitting element. Therefore, by providing a layer containing an organic compound according to an embodiment of the present invention between a hole transport material with a high HOMO energy level and the light-emitting layer 113, holes can be smoothly injected into the light-emitting layer, thereby improving the life and efficiency of the light-emitting element.

[0173] Reference Figures 1B to 1D Here, a case where an organic compound having an acceptor property is used as the hole injection material 131 and the LUMO energy level of the hole injection material 131 is lower than the HOMO energy level of the first hole transport material 132 is described. Figure 1D It is a schematic diagram showing the correlation between the HOMO level and the LUMO level of each material at this time. Figure 1C and Figure 1D The records and symbols in are as follows. HIM (131): hole injection material 131; HTM (132): first hole transport material 132; HTM (133): second hole transport material 133; HTM (134): a third hole transport material 134; Host (135): host material 135; and Object material 136.

[0174] like Figure 1B As shown, the hole transport layer 112 may also have a stacked structure of multiple layers. Specifically, the hole transport layer 112 may have the following structure: from the hole injection layer 111 side, it includes a first hole transport layer 112-a containing a first hole transport material 132, and a second hole transport layer 112-b containing a second hole transport material 133. The organic compound of one embodiment of the present invention described above may be used as the second hole transport material 133. In the above structure, the HOMO energy level of the second hole transport material 133 is lower than the HOMO energy level of the first hole transport material 132, and a light-emitting element with a long life and high efficiency can be realized. Note that the HOMO energy level of the first hole transport material 132 is preferably above -5.4 eV, so that electrons can be easily extracted from the hole injection material 131 (refer to Figure 1D ).

[0175] like Figure 1D As shown, when the difference between the HOMO energy level of the first hole transport material 132 and the HOMO energy level of the second hole transport material 133 is preferably 0.3 eV or less, and more preferably 0.2 eV or less, holes can be easily injected from the first hole transport layer 112-a to the second hole transport layer 112-b. The HOMO energy level of the organic compound according to one embodiment of the present invention is about -5.5 eV, so the organic compound can be suitable for the second hole transport material 133.

[0176] The hole transport layer 112 further includes a third hole transport layer 112-c between the second hole transport layer 112-b and the light emitting layer 113. The third hole transport layer 112-c may also include a third hole transport material 134 (see Figure 1B and Figure 1C ). At this time, if Figure 1D As shown, the HOMO energy level of the third hole transport material 134 is preferably lower than the HOMO energy level of the hole transport material of one embodiment of the present invention contained in the second hole transport layer 112-b, and the difference is preferably 0.3 eV or less, and more preferably 0.2 eV or less. Since the organic compound of one embodiment of the present invention has a HOMO energy level of about -5.5 eV, the organic compound can be suitable for the third hole transport material 134.

[0177] The HOMO energy level of the third hole transport material 134 is preferably lower than or equal to the HOMO energy level of the host material 135, so that holes can be properly transported to the light-emitting layer and the light-emitting element has a good life and efficiency.

[0178] Note that although Figure 1D The LUMO energy level of the hole injection material 131 is lower than the HOMO energy level of the host material 135, but the relationship between the two is not limited to this. That is, the LUMO energy level of the hole injection material 131 may also be higher than or equal to the HOMO energy level of the host material 135. In addition, the HOMO energy level of the host material 135 may be higher than the HOMO energy level of the first hole transport material 132, the HOMO energy level of the host material 135 may be higher than the HOMO energy level of the second hole transport material 133, and the HOMO energy level of the host material 135 may be higher than the HOMO energy level of the third hole transport material 134. In addition, the HOMO energy level of the first hole transport material 132 may be lower than the HOMO energy level of the second hole transport material 133. In addition, the HOMO energy level of the second hole transport material 133 may be lower than the HOMO energy level of the third hole transport material 134. In addition, the HOMO energy level of the first hole transport material 132 may be lower than the HOMO energy level of the third hole transport material 134.

[0179] Note that when the HOMO energy level of the guest material 136 is higher than the HOMO energy level of the host material 135, the ratio of holes injected into the guest material 136 increases according to the position of the HOMO energy level of the hole transport layer. Furthermore, the lifetime is sometimes reduced due to the deviation of the light-emitting region where holes are captured by the guest material 136. In the above case, it is preferable to adopt the structure of the light-emitting element of the present invention. As a light-emitting element that can easily have the above structure, a blue fluorescent element can be cited. It is particularly preferable to adopt the structure of the present invention for aromatic diamine compounds that emit good blue fluorescence, especially pyrene diamine compounds, thereby obtaining a light-emitting element with good lifetime, efficiency, and chromaticity.

[0180] The electron transport layer 114 is not limited to Figure 1AThe electron transport layer 114 may be a mixed film formed of multiple materials. Specifically, it may be as follows Figure 1B As shown, the first electron transport layer 114-b and the second electron transport layer 114-a are included from the light emitting layer 113. By adopting the above structure, the electron injection property from the electron injection layer 115 to the electron transport layer 114-a and the electron transport property of the electron transport layer 114-b and the electron transport layer 114-a can be adjusted, so it is preferred.

[0181] <Structural Example 2 of Light Emitting Element> Below, refer to FIG. 2A to FIG. 2C A structural example of the above-mentioned blue fluorescent element will be described.

[0182] Figure 2A The light-emitting element 120 shown contains the organic compound according to one embodiment of the present invention in at least the hole transport layer 112 . Figure 2B A structural example of a material in the light-emitting layer 113 is shown. Figure 2C The correlation between the energy levels of the materials in the light-emitting layer 113 is schematically shown.

[0183] Here, a case where the T1 energy level of the host material 121 is lower than the T1 energy level of the guest material 122 is described. Figure 2C The description and symbols in are as follows. Note that the T1 level of the host material 121 may be higher than the T1 level of the guest material 122 . Host(121): main material 121; Guest (122): guest material 122 (fluorescent material); S FH : S1 energy level of the host material 121; T FH : T1 energy level of the host material 121; S FG : S1 energy level of guest material 122 (fluorescent material); and T FG : T1 energy level of the guest material 122 (fluorescent material).

[0184] The host material 121 preferably has a function of converting triplet excitation energy into singlet excitation energy by triplet-triplet annihilation (TTA), thereby converting a portion of triplet excitation energy generated in the light-emitting layer 113 that is not originally related to fluorescent emission into singlet excitation energy in the host material 121. The singlet excitation energy is transferred to the guest material 122 (see Figure 2CThe fluorescence is extracted by the path E1). Thus, the luminous efficiency of the fluorescent element can be improved. Note that since the fluorescence of TTA is obtained through a triplet excited state with a long lifetime, delayed fluorescence is observed.

[0185] In order to efficiently transfer the singlet excitation energy to the guest material 122 in the light-emitting layer 113, it is preferred that Figure 2C As shown in FIG. 1 , the lowest energy level (S1 energy level) of the singlet excitation energy of the host material 121 is made higher than the S1 energy level of the guest material 122. In addition, the lowest energy level (T1 energy level) of the triplet excitation energy of the host material 121 is preferably lower than the T1 energy level of the guest material 122 (see FIG. 1 ). Figure 2C By adopting the above structure, TTA can be efficiently generated in the light-emitting layer 113.

[0186] Furthermore, it is preferred that the T1 energy level of the host material 121 is lower than that of the hole transport layer 112 ( Figure 2A The hole transport layer 112-c) in the light emitting layer has a T1 energy level of the material used. That is, the hole transport layer 112 preferably has a function of inhibiting the diffusion of excitons. By adopting this structure, the triplet excitons generated in the light emitting layer 113 can be inhibited from diffusing to the hole transport layer 112, thereby providing a device with high light emitting efficiency.

[0187] The organic compound according to one embodiment of the present invention has a high T1 level and a high hole-transport property and is therefore suitable as a hole-transport material in a light-emitting element using TTA. Note that the organic compound according to one embodiment of the present invention can also be used as the host material 121 .

[0188] The lowest excited singlet energy level of an organic compound can be observed from the absorption spectrum when the organic compound transitions from the singlet ground state to the lowest excited singlet state. Alternatively, the lowest excited singlet energy level can also be estimated from the peak wavelength of the fluorescence emission spectrum of the organic compound. In addition, the lowest excited triplet energy level can be observed from the absorption spectrum when the organic compound transitions from the singlet ground state to the lowest excited triplet state, but since the transition is a forbidden transition, it is sometimes difficult to observe. In this case, the lowest excited triplet energy level can also be estimated from the peak wavelength of the phosphorescence emission spectrum of the organic compound.

[0189] <Material> Next, components of a light-emitting element according to one embodiment of the present invention will be described in detail.

[0190] Luminous Layer In the light-emitting layer 113, the weight ratio of the host material 121 is at least higher than that of the guest material 122, and the guest material 122 (fluorescent material) is dispersed in the host material 121. Note that the host material 121 in the light-emitting layer 113 may be composed of one compound or a plurality of compounds.

[0191] In the light-emitting layer 113, the guest material 122 is not particularly limited, but anthracene derivatives, tetracene derivatives, As the derivatives, phenanthrene derivatives, pyrene derivatives, perylene derivatives, stilbene derivatives, acridone derivatives, coumarin derivatives, phenoxazine derivatives, phenothiazine derivatives and the like, for example, the following materials can be used.

[0192] As examples, there can be mentioned: 5,6-bis[4-(10-phenyl-9-anthracenyl)phenyl]-2,2'-bipyridine (abbreviated as PAP2BPy), 5,6-bis[4'-(10-phenyl-9-anthracenyl)biphenyl-4-yl]-2,2'-bipyridine (abbreviated as PAPP2BPy), N,N'-diphenyl-N,N'-bis[4-(9-phenyl-9H-fluoren-9-yl)phenyl]pyrene-1,6-diamine (abbreviated as 1,6FLPAPrn), N,N'-bis(3-methylphenyl)-N,N'-bis[3-(9-phenyl-9H-fluoren-9-yl)phenyl]pyrene-1,6-diamine (abbreviated as 1,6FLPAPrn), 6mMemFLPAPrn), N,N'-bis[4-(9-phenyl-9H-fluoren-9-yl)phenyl]-N,N'-bis(4-tert-butylphenyl)pyrene-1,6-diamine (abbreviated as: 1,6tBu-FLPAPrn), N,N'-bis[4-(9-phenyl-9H-fluoren-9-yl)phenyl]-N,N'-diphenyl-3,8-dicyclohexylpyrene-1,6-diamine (abbreviated as: ch-1,6FLPAPrn), N,N '-Bis[4-(9H-carbazole-9-yl)phenyl]-N,N'-diphenylstilbene-4,4'-diamine (abbreviated as: YGA2S), 4-(9H-carbazole-9-yl)-4'-(10-phenyl-9-anthracenyl)triphenylamine (abbreviated as: YGAPA), 4-(9H-carbazole-9-yl)-4'-(9,10-diphenyl-2-anthracenyl)triphenylamine (abbreviated as: 2YGAPPA), N,9-diphenyl-N-[4-(10 -phenyl-9-anthracenyl)phenyl]-9H-carbazole-3-amine (abbreviated as: PCAPA), perylene, 2,5,8,11-tetra(tert-butyl)perylene (abbreviated as: TBP), 4-(10-phenyl-9-anthracenyl)-4'-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviated as: PCBAPA), N,N"-(2-tert-butylanthracene-9,10-diyldi-4,1-phenylene)bis[N,N',N'-triphenyl-1,4-phenylenediamine amine] (abbreviated as DPABPA), N,9-diphenyl-N-[4-(9,10-diphenyl-2-anthryl)phenyl]-9H-carbazole-3-amine (abbreviated as 2PCAPPA), N-[4-(9,10-diphenyl-2-anthryl)phenyl]-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviated as 2DPAPPA), N,N,N',N',N",N",N"',N"'-octaphenyldibenzo[g,p] -2,7,10,15-tetramine (abbreviated as DBC1), coumarin 30, N-(9,10-diphenyl-2-anthryl)-N,9-diphenyl-9H-carbazole-3-amine (abbreviated as 2PCAPA), N-[9,10-bis(1,1'-biphenyl-2-yl)-2-anthryl]-N,9-diphenyl-9H-carbazole-3-amine (abbreviated as 2PCABPhA), N-(9,10-diphenyl-2-anthryl)-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviated as 2DPAPA), N-[9,10-bis(1,1'-biphenyl-2-yl)-2-anthryl]-N,9-diphenyl-9H-carbazole-3-amine (abbreviated as 2PCABPhA), -biphenyl-2-yl)-2-anthryl]-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviated as: 2DPABPhA), 9,10-bis(1,1'-biphenyl-2-yl)-N-[4-(9H-carbazole-9-yl)phenyl]-N-phenylanthracen-2-amine (abbreviated as: 2YGABPhA), N,N,9-triphenylanthracen-9-amine (abbreviated as: DPhAPhA), coumarin 6, coumarin 545T, N,N'-diphenylquinacridone (abbreviated as: DPQd), rubrene, 2,8-di-tert-butyl-5,11-bis(4-tert-butylphenyl) )-6,12-diphenyl tetracene (abbreviated as TBRb), Nile Red, 5,12-bis(1,1'-biphenyl-4-yl)-6,11-diphenyl tetracene (abbreviated as BPT), 2-(2-{2-[4-(dimethylamino)phenyl]vinyl}-6-methyl-4H-pyran-4-ylidene)malononitrile (abbreviated as DCM1), 2-{2-methyl-6-[2-(2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)vinyl]-4H-pyran-4-ylidene}malononitrile (abbreviated as DCM2), N,N,N ', N'-tetrakis(4-methylphenyl)tetracene-5,11-diamine (abbreviated as: p-mPhTD), 7,14-diphenyl-N,N,N',N'-tetrakis(4-methylphenyl)acenaphtho[1,2-a]fluoranthene-3,10-diamine (abbreviated as: p-mPhAFD), 2-{2-isopropyl-6-[2-(1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)vinyl]-4H-pyran-4-ylidene}malononitrile (abbreviated as: DCJTI), 2-{2-tert-butyl-6-[2- (1,1,7,7-tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)vinyl]-4H-pyran-4-ylidene}malononitrile (abbreviation: DCJTB), 2-(2,6-bis{2-[4-(dimethylamino)phenyl]vinyl}-4H-pyran-4-ylidene)malononitrile (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)vinyl]-4H-pyran-4-ylidene}malononitrile (abbreviation: BisDCJTM), 5,10,15,20-tetraphenylbisbenzo[5,6]indeno[1,2,3-cd:1',2',3'-lm]perylene, etc.

[0193] Note that the light-emitting layer 113 may include a material other than the host material 121 and the guest material 122 .

[0194] Although there is no particular limitation on the material that can be used for the light-emitting layer 113, examples thereof include tris(8-hydroxyquinoline)aluminum(III) (abbreviated as Alq), tris(4-methyl-8-hydroxyquinoline)aluminum(III) (abbreviated as Almq3), bis(10-hydroxybenzo[h]quinoline)beryllium(II) (abbreviated as BeBq2), bis(2-methyl-8-hydroxyquinoline)(4-phenylphenol)aluminum(III) (abbreviated as BAlq), bis(8-hydroxyquinoline) ) zinc (II) (abbreviated as: Znq), bis[2-(2-benzoxazolyl)phenol] zinc (II) (abbreviated as: ZnPBO), bis[2-(2-benzothiazolyl)phenol] zinc (II) (abbreviated as: ZnBTZ) and other metal complexes; 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviated as: PBD), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazole-2-yl]benzene (abbreviated as: OXD- 7), 3-(4-biphenyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (abbreviation: TAZ), 2,2',2"-(1,3,5-phenyltriyl)tris(1-phenyl-1H-benzimidazole) (abbreviation: TPBI), bathophenanthroline (abbreviation: BPhen), bathocuproin (abbreviation: BCP), 9-[4-(5-phenyl-1,3,4-oxadiazol-2-yl)phenyl]-9H-carbazole (abbreviation: CO11) and other heterocyclic compounds compounds; aromatic amine compounds such as 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviated as NPB or α-NPD), N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (abbreviated as TPD), 4,4'-bis[N-(spiro-9,9'-bifluorene-2-yl)-N-phenylamino]biphenyl (abbreviated as BSPB). In addition, anthracene derivatives, phenanthrene derivatives, pyrene derivatives, Derivatives, dibenzo[g,p] Derivatives and other condensed polycyclic aromatic compounds. Specifically, 9,10-diphenylanthracene (abbreviation: DPAnth), N,N-diphenyl-9-[4-(10-phenyl-9-anthracenyl)phenyl]-9H-carbazole-3-amine (abbreviation: CzA1PA), 4-(10-phenyl-9-anthracenyl)triphenylamine (abbreviation: DPhPA), 4-(9H-carbazole-9-yl)-4'-(10-phenyl-9-anthracenyl)triphenylamine (abbreviation: YGAPA), N,9-diphenyl-N -[4-(10-phenyl-9-anthracenyl)phenyl]-9H-carbazole-3-amine (abbreviated as: PCAPA), N,9-diphenyl-N-{4-[4-(10-phenyl-9-anthracenyl)phenyl]phenyl}-9H-carbazole-3-amine (abbreviated as: PCAPBA), N,9-diphenyl-N-(9,10-diphenyl-2-anthracenyl)-9H-carbazole-3-amine (abbreviated as: 2PCAPA), 6,12-dimethoxy-5,11-diphenyl N,N,N',N',N",N",N"',N"'-octaphenyldibenzo[g,p] -2,7,10,15-tetramine (abbreviation: DBC1), 9-phenyl-3-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviation: PCzPA), 3,6-diphenyl-9-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviation: DPCzPA), 9,10-bis(3,5-diphenylphenyl)anthracene (abbreviation: DPPA), 9,10-di(2-naphthyl) The guest material 122 may be substituted with 1,3,5-tri(1-pyrenyl)benzene or 1,3,5-tri(1-pyrenyl)benzene. The guest material 122 may be substituted with 1,3,5-tri(1-pyrenyl)benzene or 1,3,5-tri(1-pyrenyl)benzene. The guest material 122 may be substituted with 1,3,5-tri(1-pyrenyl)benzene or 1,3,5-tri(1-pyrenyl)benzene. The guest material 122 may be substituted with 1,3,5-tri(1-pyrenyl)benzene or 1,3,5-tri(1-pyrenyl)benzene. The guest material 122 may be substituted with 1,3,5-tri(1-pyrenyl)benzene or 1,3,5-tri(1-pyrenyl)benzene. The guest material 122 may be substituted with 1,3,5-tri(1-pyrenyl)benzene or 1,3,5-tri(1-pyrenyl)benzene.

[0195] Note that the light-emitting layer 113 may have a structure in which two or more layers are stacked. For example, in the case where the light-emitting layer 113 is formed by stacking a first light-emitting layer and a second light-emitting layer in this order from the hole transport layer side, the first light-emitting layer is formed using a substance having a hole transport property as a main material, and the second light-emitting layer is formed using a substance having an electron transport property as a main material.

[0196] Next, Figure 1A The light emitting element 100 and Figure 2A The details of other components of the light emitting element 120 are described below.

[0197] Hole injection layer The hole injection layer 111 has the function of lowering the injection barrier of holes from one of the pair of electrodes (electrode 101 or electrode 102) to promote hole injection, and is formed, for example, using transition metal oxides, phthalocyanine derivatives or aromatic amines. As transition metal oxides, molybdenum oxides, vanadium oxides, ruthenium oxides, tungsten oxides, manganese oxides, etc. can be cited. As phthalocyanine derivatives, phthalocyanine and metal phthalocyanines can be cited. As aromatic amines, benzidine derivatives and phenylenediamine derivatives can be cited. In addition, polymer compounds such as polythiophene or polyaniline can also be used, typically: poly (ethyldioxythiophene) / poly (styrene sulfonic acid) as self-doped polythiophene, etc.

[0198] As the hole injection layer 111, a layer having a composite material composed of a hole transport material and a material having the property of receiving electrons from the hole transport material can be used. Alternatively, a stack of a layer containing an electron accepting material and a layer containing a hole transporting material can also be used. In a steady state or in the presence of an electric field, the transfer of charges can be carried out between these materials. As electron accepting materials, organic acceptors such as quinone dimethane derivatives, tetrachlorobenzoquinone derivatives, and hexaazatriphenylene derivatives can be cited. Specifically, compounds having electron-withdrawing groups (halogen or cyano) such as 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinone dimethane (abbreviated as: F4-TCNQ), chloranil, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene (abbreviated as: HAT-CN) can be cited. In addition, transition metal oxides, such as oxides of metals from Groups 4 to 8, can also be used. Specifically, vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, molybdenum oxide, tungsten oxide, manganese oxide, rhenium oxide, etc. can be used. Molybdenum oxide is particularly preferably used because it is stable even in the atmosphere, has low hygroscopicity, and is easy to handle.

[0199] As the hole transport material, a material having a hole transport property higher than an electron transport property can be used, and preferably a material having a 1×10 -6 cm 2 / Vs or higher. Specifically, aromatic amine compounds, carbazole derivatives, aromatic hydrocarbons, stilbene derivatives, etc. can be used. In addition, the above-mentioned hole transport material can also be a polymer compound.

[0200] As materials with high hole transport properties, for example, as aromatic amine compounds, there can be mentioned 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), etc.

[0201] Specific examples of carbazole derivatives include 3-[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA1), 3,6-bis[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA2), 3,6-bis[N-(4-diphenylaminophenyl)-N-(1-naphthyl)amino]-9-phenylcarbazole (abbreviation: PCzTPN2), 3-[N-(9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3,6-bis[N-(9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA2), and 3-[N-(1-naphthyl)-N-(9-phenylcarbazole-3-yl)amino]-9-phenylcarbazole (abbreviation: PCzPCN1).

[0202] Examples of carbazole derivatives include 4,4'-di(N-carbazolyl)biphenyl (abbreviation: CBP), 1,3,5-tris[4-(N-carbazolyl)phenyl]benzene (abbreviation: TCPB), 9-[4-(10-phenyl-9-anthracenyl)phenyl]-9H-carbazole (abbreviation: CzPA), and 1,4-bis[4-(N-carbazolyl)phenyl]-2,3,5,6-tetraphenylbenzene.

[0203] Examples of the 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'-bianthracene, 10,10'-diphenyl-9,9'-bianthracene, 10,10'-bis(2-phenylphenyl)-9,9'-bianthracene, 10,10'-bis[(2,3,4,5,6-pentaphenyl)phenyl]-9,9'-bianthracene, anthracene, tetracene, rubrene, perylene, 2,5,8,11-tetra(tert-butyl)perylene, and the like. In addition, pentacene, coronene, and the like can also be used. More preferably, a 1×10 -6 cm 2 / Vs or more and an aromatic hydrocarbon having 14 to 42 carbon atoms.

[0204] Aromatic hydrocarbons 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).

[0205] In addition, high molecular weight 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.

[0206] As materials with high hole transport properties, for example, 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviated as NPB or α-NPD), N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl]-4,4'-diamine (abbreviated as TPD), 4,4',4"-tri(carbazol-9-yl)triphenylamine (abbreviated as TCTA), 4,4',4"-tri[N-(1-naphthyl)-N-phenylamino]triphenylamine (abbreviated as 1'-TNATA), 4,4',4"-tri(N,N-diphenylamino)triphenylamine (abbreviated as TDATA), 4,4',4"-tri[N-(3-methylphenyl)-N-phenylamino]triphenylamine (abbreviated as TDATA), 4,4',4"-tri[N-(3-methylphenyl)-N-phenylamino]triphenylamine (abbreviated as TCTA), 4,4',4"-tri[N-(1-naphthyl)-N-phenylamino]triphenylamine (abbreviated as 1'-TNATA), 4,4',4"-tri(N,N-diphenylamino)triphenylamine (abbreviated as TDATA), 4,4',4"-tri[N-(3-methylphenyl)-N-phenylamino]triphenylamine (abbreviated as TCTA), 4,4',4"-tri[N-(1-naphthyl)-N-phenylamino]triphenylamine (abbreviated as 1'-TNATA ... Abbreviation: MTDATA), 4,4'-bis[N-(spiro-9,9'-bifluoren-2-yl)-N-phenylamino]biphenyl (abbreviation: BSPB), 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP), 4-phenyl-3'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: mBPAFLP), N-(9,9-dimethyl-9H-fluoren-2-yl)-N-{9,9-dimethyl-2-[N'-phenyl-N'-(9,9-dimethyl-9H-fluoren-2-yl)amino]-9H-fluoren-7-yl}phenylamine (abbreviation: DFLADFL), N-(9,9-dimethyl-2-diphenylamino-9H-fluoren-7-yl)diphenylamine ( Abbreviation: DPNF), 2-[N-(4-diphenylaminophenyl)-N-phenylamino]spiro-9,9'-bifluorene (abbreviation: DPASF), 4-phenyl-4'-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBA1BP), 4,4'-diphenyl-4"-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBBi1BP), 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBANB), 4,4'-di(1-naphthyl)-4"-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviation: PCBNBB), 4-phenyldiphenyl-(9-phenyl-9H-carbazole-3-yl)triphenylamine oxazol-3-yl)amine (abbreviation: PCA1BP), N,N'-bis(9-phenylcarbazole-3-yl)-N,N'-diphenylbenzene-1,3-diamine (abbreviation: PCA2B), N,N',N"-triphenyl-N,N',N"-tri(9-phenylcarbazole-3-yl)benzene-1,3,5-triamine (abbreviation: PCA3B), N-(4-biphenyl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-9-phenyl-9H-carbazole-3-amine (abbreviation: PCBiF), N-(1,1'-biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-9,9-dimethyl-9H-fluoren-2-amine (abbreviation: PCBBiF), 9,9-dimethyl-N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]fluoren-2-amine (abbreviation: PCBAF), N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]spiro-9,9'-bifluoren-2-amine (abbreviation: PCBASF), 2-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]spiro-9,9'-bifluoren-2-amine (abbreviation: PCASF), 2, Aromatic amine compounds such as 7-bis[N-(4-diphenylaminophenyl)-N-phenylamino]spiro-9,9'-bifluorene (abbreviation: DPA2SF), N-[4-(9H-carbazole-9-yl)phenyl]-N-(4-phenyl)phenylaniline (abbreviation: YGA1BP), N,N'-bis[4-(carbazole-9-yl)phenyl]-N,N'-diphenyl-9,9-dimethylfluorene-2,7-diamine (abbreviation: YGA2F), etc. In addition, 3-[4-(1-naphthyl)-phenyl]-9-phenyl-9H-carbazole (abbreviated as PCPN), 3-[4-(9-phenanthrenyl)-phenyl]-9-phenyl-9H-carbazole (abbreviated as PCPPn), 3,3'-bis(9-phenyl-9H-carbazole) (abbreviated as PCCP), 1,3-bis(N-carbazolyl)benzene (abbreviated as mCP), 3,6-bis(3,5-diphenylphenyl)-9-phenylcarbazole (abbreviated as PCPPn) can be used. : CzTP), 3,6-bis(9H-carbazole-9-yl)-9-phenyl-9H-carbazole (abbreviated as PhCzGI), 2,8-bis(9H-carbazole-9-yl)-dibenzothiophene (abbreviated as Cz2DBT), 4-{3-[3-(9-phenyl-9H-fluorene-9-yl)phenyl]phenyl}dibenzofuran (abbreviated as mmDBFFLBi-II), 4,4',4"-(benzene-1,3,5-triyl)tri(dibenzofuran) Amine compounds, carbazole compounds, thiophene compounds, furan compounds, fluorene compounds, triphenylene compounds, phenanthrene compounds, etc. are used. Among them, compounds having at least one of a pyrrole skeleton, a furan skeleton, a thiophene skeleton and an aromatic amine skeleton are stable and have good reliability, so they are preferred. In addition, compounds having the above skeletons have high hole transport properties and also contribute to reducing the driving voltage. ,

[0207] Hole transport layer The hole transport layer 112 is a layer containing a hole transport material, and the hole transport material exemplified as the material of the hole injection layer 111 can be used. In order for the hole transport layer 112 to have the function of transporting the holes injected into the hole injection layer 111 to the light-emitting layer 113, the HOMO energy level of the hole transport layer 112 is preferably the same as or close to the HOMO energy level of the hole injection layer 111.

[0208] As the hole transport material, it is preferred to use a 1×10 -6 cm 2 / Vs or higher. Note that any substance other than the above substances may be used as long as the hole transport property is higher than the electron transport property. The layer including the substance with high hole transport property is not limited to a single layer, and two or more layers including the above substances may be stacked.

[0209] Alternatively, the organic compound according to one embodiment of the present invention may be used.

[0210] Electron Transport Layer The electron transport layer 114 has a function of transporting electrons injected from the other of the pair of electrodes (electrode 101 or electrode 102) through the electron injection layer 115 to the light-emitting layer 113. As the electron transport material, a material having a higher electron transport property than a hole transport property can be used, and preferably a material having a 1×10 -6 cm 2 / Vs or more of the electron mobility. As a compound that easily receives electrons (a material with electron transport properties), π-electron-deficient heteroaromatic compounds such as nitrogen-containing heteroaromatic compounds or metal complexes can be used. Specifically, metal complexes including quinoline ligands, benzoquinoline ligands, oxazole ligands or thiazole ligands, oxadiazole derivatives, triazole derivatives, benzimidazole derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives, phenanthroline derivatives, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, triazine derivatives, etc. can be cited. Note that as long as the electron transport property is higher than the hole transport property, substances other than the above substances can be used. The electron transport layer 114 is not limited to a single layer, and more than two layers containing the above substances can be stacked.

[0211] Specifically, examples of the metal complex having a quinoline skeleton or a benzoquinoline skeleton include tris(8-hydroxyquinoline)aluminum(III) (abbreviation: Alq), tris(4-methyl-8-hydroxyquinoline)aluminum(III) (abbreviation: Almq3), bis(10-hydroxybenzo[h]quinoline)beryllium(II) (abbreviation: BeBq2), bis(2-methyl-8-hydroxyquinoline)(4-phenylphenol)aluminum(III) (abbreviation: BAlq), bis(8-hydroxyquinoline)zinc(II) (abbreviation: Znq), and the like. In addition, other metal complexes such as bis[2-(2-benzoxazolyl)phenol]zinc(II) (abbreviation: ZnPBO), bis[2- [2-benzothiazolyl)phenol] zinc (II) (abbreviation: ZnBTZ) and other metal complexes having oxazolyl or thiazole ligands. In addition to the metal complexes, 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazole-2-yl]benzene (abbreviation: OXD-7), 9-[4-(5-phenyl-1,3,4-oxadiazole-2-yl)phenyl]-9H-carbazole (abbreviation: CO11), 3-(4-biphenyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (abbreviation: TAZ), 9-[4-(4,5-diphenyl-4H-1,2,4-triazol-3-yl)phenyl]-9H-carbazole can also be used. azole (abbreviated as: CzTAZ1), 2,2',2"-(1,3,5-benzenetriyl)tri(1-phenyl-1H-benzimidazole) (abbreviated as: TPBI), 2-[3-(dibenzothiophen-4-yl)phenyl]-1-phenyl-1H-benzimidazole (abbreviated as: mDBTBIm-II), bathophenanthroline (abbreviated as: BPhen), 2,9-bis(naphthalene-2-yl)-4,7-diphenyl-1,10-phenanthroline (abbreviated as: NBPhen), bathocuproin (abbreviated as: BCP) and other heterocyclic compounds; 2-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviated as: 2mDBTPDBq-II ), 2-[3'-(dibenzothiophene-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviated as: 2mDBTBPDBq-II), 2-[3'-(9H-carbazole-9-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviated as: 2mCzBPDBq), 2-[4-(3,6-diphenyl-9H-carbazole-9-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviated as: 2CzPDBq-III), 7-[3-(dibenzothiophene-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviated as: 7mDBTPDBq-II), 6-[3-(dibenzothiophene-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviated as: 7mDBTPDBq-II), heterocyclic compounds having a diazine skeleton, such as 2-{4-[3-(4-dibenzothienyl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 6mDBTPDBq-II), 2-[3-(3,9'-bi-9H-carbazole-9-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mCzCzPDBq), 4,6-bis[3-(phenanthrene-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm), 4,6-bis[3-(4-dibenzothienyl)phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-II), and 4,6-bis[3-(9H-carbazole-9-yl)phenyl]pyrimidine (abbreviation: 4,6mCzP2Pm); 2-{4-[3-(4-dibenzothienyl)phenyl]pyrimidine (abbreviation: 4,6mDBTP2Pm-II), and 4,6-bis[3-(9H-carbazole-9-yl)phenyl]pyrimidine (abbreviation: 4,6mCzP2Pm); Heterocyclic compounds having a triazine skeleton, such as (N-phenyl-9H-carbazole-3-yl)-9H-carbazole-9-yl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviated as PCCzPTzn); heterocyclic compounds having a pyridine skeleton, such as 3,5-bis[3-(9H-carbazole-9-yl)phenyl]pyridine (abbreviated as 35DCzPPy), 1,3,5-tris[3-(3-pyridyl)phenyl]benzene (abbreviated as TmPyPB); heteroaromatic compounds such as 4,4'-bis(5-methylbenzoxazolyl-2-yl)stilbene (abbreviated as BzOs). Among the above heterocyclic compounds, heterocyclic compounds having at least one of a triazine skeleton, a diazine (pyrimidine, pyrazine, pyridazine) skeleton and a pyridine skeleton are stable and have good reliability, so they are preferred. In addition, heterocyclic compounds having the above skeletons have high electron transport properties, which also helps to reduce the driving voltage. In addition, polymer compounds such as poly(2,5-pyridinediyl) (abbreviated as PPy), poly[(9,9-dihexylfluorene-2,7-diyl)-co-(pyridine-3,5-diyl)] (abbreviated as PF-Py), and poly[(9,9-dioctylfluorene-2,7-diyl)-co-(2,2'-bipyridine-6,6'-diyl)] (abbreviated as PF-BPy) can also be used. The substances described here are mainly polymers with an electron mobility of 1×10 -6 cm 2 / Vs or above.

[0212] Note that any substance other than the above substances may be used as long as it has a higher electron-transport property than a hole-transport property. The electron-transport layer 114 is not limited to a single layer, and two or more layers including the above substances may be stacked.

[0213] In addition, a layer for controlling the movement of carriers can be provided between the electron transport layer 114 and the light-emitting layer 113. This is a layer formed by adding a small amount of a substance with high electron capture properties to the above-mentioned material with high electron transport properties. By suppressing the movement of carriers, the balance of carriers can be adjusted. This structure has a great effect on suppressing problems caused by electrons passing through the light-emitting layer (such as a decrease in the life of the element).

[0214] In addition, n-type compound semiconductors can also be used, for example, oxides such as titanium oxide, zinc oxide, silicon oxide, tin oxide, tungsten oxide, tantalum oxide, barium titanate, barium zirconate, zirconium oxide, hafnium oxide, aluminum oxide, yttrium oxide, and zirconium silicate; nitrides such as silicon nitride; cadmium sulfide, zinc selenide, and zinc sulfide, etc.

[0215] 《Electron injection layer》 The electron injection layer 115 has the function of lowering the injection barrier of electrons from the electrode 102 to promote electron injection. For example, Group 1 metals, Group 2 metals or their oxides, halides, carbonates, etc. can be used. In addition, a composite material of an electron transport material (described above) and a material that is electron-donating to the electron transport material can also be used. As electron-donating materials, Group 1 metals, Group 2 metals or their oxides, etc. can be cited. Specifically, alkali metals, alkaline earth metals or compounds of these metals such as lithium fluoride, sodium fluoride, cesium fluoride, calcium fluoride and lithium oxide can be used. In addition, rare earth metal compounds such as erbium fluoride can be used. In addition, electron salts can also be used for the electron injection layer 115. As the electron salt, for example, a substance that adds electrons to a mixed oxide of calcium and aluminum at a high concentration can be cited. In addition, substances that can be used for the electron transport layer 114 can also be used for the electron injection layer 115.

[0216] In addition, a composite material formed by mixing an organic compound with an electron donor (donor) can also be used for the electron injection layer 115. This composite material has excellent electron injection and electron transport properties because electrons are generated in the organic compound by the electron donor. In this case, the organic compound is preferably a material with excellent performance in transporting the generated electrons. Specifically, for example, the substance (metal complex, heteroaromatic compound, etc.) forming the electron transport layer 114 as described above can be used. As an electron donor, any substance that exhibits electron donating properties to organic compounds can be used. Specifically, alkali metals, alkaline earth metals and rare earth metals are preferably used, and lithium, sodium, cesium, magnesium, calcium, erbium, ytterbium, etc. can be mentioned. In addition, alkali metal oxides or alkaline earth metal oxides are preferably used, and lithium oxide, calcium oxide, barium oxide, etc. can be mentioned. In addition, Lewis bases such as magnesium oxide can also be used. In addition, organic compounds such as tetrathiafulvalene (abbreviated as: TTF) can also be used.

[0217] Note that the above-mentioned light-emitting layer, hole injection layer, hole transport layer, electron transport layer and electron injection layer can be formed by evaporation (including vacuum evaporation), inkjet, coating, gravure printing, etc. In addition to the above-mentioned materials, inorganic compounds such as quantum dots or high molecular compounds (oligomers, dendrimers, polymers, etc.) can also be used for the above-mentioned light-emitting layer, hole injection layer, hole transport layer, electron transport layer and electron injection layer.

[0218] "Quantum Dot" Quantum dots are semiconductor nanocrystals with a size of several nanometers to tens of nanometers and include 1×10 3 to 1 10 6The energy transfer of quantum dots depends on their size, so even quantum dots made of the same substance have different emission wavelengths depending on their size. Therefore, by changing the size of the quantum dots used, the emission wavelength can be easily changed.

[0219] The peak width of the emission spectrum of quantum dots is narrow, so luminescence with high color purity can be obtained. Furthermore, the theoretical internal quantum efficiency of quantum dots is considered to be almost 100%, that is, it greatly exceeds 25% of organic compounds that exhibit fluorescent luminescence and is equal to organic compounds that exhibit phosphorescent luminescence. Therefore, by using quantum dots as luminescent materials, a light-emitting element with high luminescence efficiency can be obtained. Moreover, quantum dots as inorganic materials are also excellent in substantial stability, so a light-emitting element with a long life can be obtained.

[0220] As materials constituting quantum dots, there can be cited Group 14 elements, Group 15 elements, Group 16 elements, compounds containing multiple Group 14 elements, compounds of elements from Groups 4 to 14 and Group 16 elements, compounds of Group 2 elements and Group 16 elements, compounds of Group 13 elements and Group 15 elements, compounds of Group 13 elements and Group 17 elements, compounds of Group 14 elements and Group 15 elements, compounds of Group 11 elements and Group 17 elements, iron oxides, titanium oxides, chalcogenide spinels, various semiconductor clusters, and the like.

[0221] Specifically, cadmium selenide, cadmium sulfide, cadmium telluride, zinc selenide, zinc oxide, zinc sulfide, zinc telluride, mercury sulfide, mercury selenide, mercury telluride, indium arsenide, indium phosphide, gallium arsenide, gallium phosphide, indium nitride, gallium nitride, indium antimonide, gallium antimonide, aluminum phosphide, aluminum arsenide, aluminum antimonide, lead selenide, lead telluride, lead sulfide, indium selenide, indium telluride, indium sulfide, gallium selenide, arsenic sulfide, arsenic selenide, arsenic telluride, antimony sulfide, antimony selenide, antimony telluride, bismuth sulfide, bismuth selenide, bismuth telluride, silicon, silicon carbide, germanium, tin, selenium, tellurium, boron, carbon, phosphorus, boron nitride, boron phosphide, boron arsenide, aluminum nitride, aluminum sulfide, barium sulfide, barium selenide, barium telluride, calcium sulfide, calcium selenide, calcium telluride, Beryllium sulfide, beryllium selenide, beryllium telluride, magnesium sulfide, magnesium selenide, germanium sulfide, germanium selenide, germanium telluride, tin sulfide, tin sulfide, tin selenide, tin telluride, lead oxide, copper fluoride, copper chloride, copper bromide, copper iodide, copper oxide, copper selenide, nickel oxide, cobalt oxide, cobalt sulfide, ferroferric oxide, iron sulfide, manganese oxide, molybdenum sulfide, vanadium oxide, tungsten oxide, tantalum oxide, titanium oxide, zirconium oxide, silicon nitride, germanium nitride, aluminum oxide, barium titanate, selenium zinc cadmium compound, indium arsenic phosphorus compound, cadmium selenium sulfur compound, cadmium selenium tellurium compound, indium gallium arsenic compound, indium gallium selenide compound, indium selenium sulfur compound, copper indium sulfur compound and their combination, etc., but not limited to this. So-called alloy-type quantum dots whose composition is represented by an arbitrary number can also be used. For example, cadmium-selenium-sulfur alloy quantum dots are one of the effective means for obtaining blue light emission because the emission wavelength can be changed by changing the content ratio of the elements.

[0222] As quantum dots, any one of core-type quantum dots, core-shell quantum dots, core-multi-shell quantum dots, etc. can be used. Note that by using other inorganic materials covering the core and having a wider band gap to form a shell, the influence of defects or dangling bonds present on the surface of the nanocrystal can be reduced. Since the quantum efficiency of luminescence can be greatly improved, it is preferred to use core-shell or core-multi-shell quantum dots. As an example of the material of the shell, zinc sulfide or zinc oxide can be cited.

[0223] Since the proportion of surface atoms of quantum dots is high, the reactivity is high and aggregation is easy to occur. Therefore, the surface of the quantum dots is preferably attached with a protective agent or provided with a protective group. Aggregation can be prevented and the solubility in the solvent can be improved by attaching a protective agent or providing a protective group. Reactivity can also be reduced and electrical stability can be improved. As a protective agent (or protective group), for example, polyoxyethylene alkyl ethers such as lauryl alcohol polyoxyethylene ether, polyoxyethylene stearate, and polyoxyethylene lauryl ether; trialkyl phosphines such as tripropyl phosphine, tributyl phosphine, trihexyl phosphine, and trioctyl phosphine; polyoxyethylene alkyl phenyl ethers such as polyoxyethylene n-octyl phenyl ether and polyoxyethylene n-nonyl phenyl ether; tertiary amines such as tri(n-hexyl)amine, tri(n-octyl)amine, and tri(n-decyl)amine; organic phosphorus compounds such as tripropyl phosphine oxide, tributyl phosphine oxide, trihexyl phosphine oxide, trioctyl phosphine oxide, and tridecyl phosphine oxide; polyethylene glycol dilaurate , polyethylene glycol diesters such as polyethylene glycol distearate; organic nitrogen compounds such as nitrogen-containing aromatic compounds such as pyridine, lutiidine, collidine, quinoline, etc.; aminoalkanes such as hexylamine, octylamine, decylamine, dodecylamine, tetradecylamine, hexadecylamine, octadecylamine, etc.; dialkyl sulfides such as dibutyl sulfide; dialkyl sulfoxides such as dimethyl sulfoxide and dibutyl sulfoxide; organic sulfur compounds such as sulfur-containing aromatic compounds such as thiophene; higher fatty acids such as palmitic acid, stearic acid, oleic acid; ethanol; sorbitan fatty acid esters; fatty acid-modified polyesters; tertiary amine-modified polyurethanes; polyethyleneimines, etc.

[0224] The smaller the size of the quantum dot, the larger the band gap, so the size is appropriately adjusted to obtain the desired wavelength of light. The smaller the crystal size, the more the light emission of the quantum dot migrates to the blue side (i.e., the high energy side), so by changing the size of the quantum dot, the luminescence wavelength can be adjusted to the wavelength region of the spectrum in the ultraviolet region, the visible light region, and the infrared region. The size (diameter) of the commonly used quantum dots is more than 0.5nm and less than 20nm, preferably more than 1nm and less than 10nm. The smaller the size distribution of the quantum dot, the narrower the emission spectrum, so luminescence with high color purity can be obtained. There is no particular restriction on the shape of the quantum dot, which can be spherical, rod-shaped, disc-shaped, etc. The quantum rod as a rod-shaped quantum dot has the function of presenting directional light, so by using the quantum rod as a luminescent material, a light-emitting element with higher external quantum efficiency can be obtained.

[0225] In organic EL elements, the concentration quenching of the luminescent material is usually suppressed by dispersing the luminescent material in the host material, thereby improving the luminous efficiency. The host material needs to have a singlet excitation energy level or a triplet excitation energy level higher than the luminescent material. In particular, when a blue phosphorescent material is used as a luminescent material, a host material with a triplet excitation energy level higher than the blue phosphorescent material and a long service life is required, and the development of such a material is extremely difficult. Here, quantum dots can ensure luminous efficiency even when only quantum dots are used to form a luminescent layer without using a host material, so a luminescent element with a long service life can be obtained. When only quantum dots are used to form a luminescent layer, the quantum dots preferably have a core-shell structure (including a core-multi-shell structure).

[0226] When quantum dots are used as the light-emitting material of the light-emitting layer, the thickness of the light-emitting layer is between 3 nm and 100 nm, preferably between 10 nm and 100 nm, and the ratio of quantum dots contained in the light-emitting layer is between 1 vol.% and 100 vol.%. Note that it is preferred that the light-emitting layer is formed only by quantum dots. In order to form a light-emitting layer in which the quantum dots are used as a light-emitting material and dispersed in a host material, the quantum dots can be dispersed in the host material or the host material and the quantum dots can be dissolved or dispersed in a suitable liquid medium, and a wet method (spin coating, casting, dye coating, blade coating, roller coating, inkjet, printing, spray coating, curtain coating, Langmuir-Brokett method, etc.) is used. In addition to the above-mentioned wet method, a vacuum evaporation method is preferably used for the light-emitting layer using a phosphorescent light-emitting material.

[0227] As the liquid medium used for the wet method, for example, ketones such as methyl ethyl ketone and cyclohexanone; fatty acid esters such as ethyl acetate; halogenated hydrocarbons such as dichlorobenzene; aromatic hydrocarbons such as toluene, xylene, mesitylene, cyclohexylbenzene; aliphatic hydrocarbons such as cyclohexane, decalin, dodecane; organic solvents such as dimethylformamide (DMF) and dimethyl sulfoxide (DMSO).

[0228] A pair of electrodes The electrode 101 and the electrode 102 are used as an anode or a cathode of the light-emitting element. The electrode 101 and the electrode 102 can be formed using a metal, an alloy, a conductive compound, a mixture or a stacked body thereof, or the like.

[0229] One of the electrode 101 and the electrode 102 is preferably formed using a conductive material having a function of reflecting light. As the conductive material, aluminum (Al) and alloys containing Al can be cited. As alloys containing Al, alloys containing Al and L (L represents one or more of titanium (Ti), neodymium (Nd), nickel (Ni) and lanthanum (La)) can be cited, such as alloys containing Al and Ti or alloys containing Al, Ni and La. Aluminum has low resistivity and high light reflectivity. Since aluminum is contained in large quantities in the earth's crust and is not expensive, the use of aluminum can reduce the manufacturing cost of the light-emitting element. In addition, silver (Ag), alloys containing Ag, N (N represents one or more of yttrium (Y), Nd, magnesium (Mg), ytterbium (Yb), Al, Ti, gallium (Ga), zinc (Zn), indium (In), tungsten (W), manganese (Mn), tin (Sn), iron (Fe), Ni, copper (Cu), palladium (Pd), iridium (Ir) and gold (Au) can also be used. As alloys containing silver, for example, the following alloys can be cited: alloys containing silver, palladium and copper; alloys containing silver and copper; alloys containing silver and magnesium; alloys containing silver and nickel; alloys containing silver and gold; and alloys containing silver and ytterbium, etc. In addition to the above materials, transition metals such as tungsten, chromium (Cr), molybdenum (Mo), copper and titanium can be used.

[0230] The light emitted from the light emitting layer is extracted through the electrode 101 and / or the electrode 102. Therefore, at least one of the electrode 101 and the electrode 102 is preferably formed using a conductive material having a light transmitting function. Examples of the conductive material include a material having a visible light transmittance of 40% or more and 100% or less, preferably 60% or more and 100% or less, and a resistivity of 1×10 -2 Conductive materials with a resistance of Ω·cm or less.

[0231] The electrodes 101 and 102 may also be formed using a conductive material having a function of transmitting light and a function of reflecting light. Examples of the conductive material include a material having a visible light reflectance of 20% or more and 80% or less, preferably 40% or more and 70% or less, and a resistivity of 1×10 -2 Conductive materials with a resistance of less than Ω·cm. For example, one or more of conductive metals, alloys and conductive compounds can be used. Specifically, metal oxides such as indium tin oxide (hereinafter referred to as ITO), indium tin oxide containing silicon or silicon oxide (abbreviated as: ITSO), indium oxide-zinc oxide, indium oxide-tin oxide containing titanium, indium-titanium oxide, indium oxide containing tungsten oxide and zinc oxide. A metal film having a thickness that allows light to be transmitted (preferably a thickness of more than 1 nm and less than 30 nm) can be used. As the metal, for example, alloys of Ag, Ag and Al, Ag and Mg, Ag and Au, and Ag and Yb can be used.

[0232] In this specification, etc., the material that allows light to pass can be a material that allows visible light to pass and has conductivity. Examples of such materials include the oxide conductors represented by ITO, oxide semiconductors, or organic conductors containing organic matter. As organic conductors containing organic matter, for example, composite materials containing mixed organic compounds and electron donors (donors), composite materials containing mixed organic compounds and electron acceptors (acceptors), etc. can be cited. In addition, inorganic carbon materials such as graphene can also be used. The resistivity of the material is preferably 1×10 5 Ω·cm or less, more preferably 1×10 4 Ω·cm or less.

[0233] In addition, the electrode 101 and / or the electrode 102 may be formed by stacking a plurality of the above materials.

[0234] In order to improve the light extraction efficiency, a material having a refractive index higher than that of an electrode having the function of transmitting light can be formed in contact with the electrode. Such a material can be a conductive material or a non-conductive material as long as it has the function of transmitting visible light. For example, in addition to the above-mentioned oxide conductors, oxide semiconductors and organic substances can also be cited. As organic substances, for example, materials exemplified as light-emitting layers, hole injection layers, hole transport layers, electron transport layers, or electron injection layers can be cited. In addition, inorganic carbon materials or thin films having a thickness that allows light to be transmitted can also be used. In addition, multiple layers having a thickness of more than a few nm and less than tens of nm can also be used.

[0235] When the electrode 101 or the electrode 102 is used as a cathode, it is preferable to use a material with a small work function (3.8 eV or less). For example, elements belonging to Group 1 or Group 2 of the periodic table (e.g., alkali metals such as lithium, sodium, and cesium, alkaline earth metals such as calcium or strontium, magnesium, etc.), alloys containing the above elements (e.g., Ag and Mg or Al and Li), rare earth metals such as europium (Eu) or Yb, alloys containing the above rare earth metals, alloys containing aluminum and silver, etc. can be used.

[0236] When the electrode 101 or the electrode 102 is used as an anode, it is preferable to use a material having a large work function (4.0 eV or more).

[0237] Alternatively, the electrodes 101 and 102 may be stacked layers of a conductive material having a function of reflecting light and a conductive material having a function of transmitting light. In this case, both the electrodes 101 and 102 may have a function of adjusting the optical distance so that the desired light from each light-emitting layer resonates and enhances its wavelength, so this structure is preferred.

[0238] As a method for forming the electrodes 101 and 102 , sputtering, vapor deposition, printing, coating, molecular beam epitaxy (MBE), CVD, pulse laser deposition, atomic layer deposition (ALD), or the like can be appropriately used.

[0239] Substrate The light-emitting element of one embodiment of the present invention can be formed over a substrate of glass, plastic, etc. The order of stacking layers on the substrate may be stacked sequentially from the electrode 101 side or from the electrode 102 side.

[0240] As a substrate capable of forming a light-emitting element of one embodiment of the present invention, for example, glass, quartz or plastic can be used. Alternatively, a flexible substrate can also be used. A flexible substrate is a substrate that can be bent, such as a plastic substrate made of polycarbonate or polyarylate. In addition, a film, an inorganic vapor-deposited film, etc. can be used. As long as it serves as a support in the manufacturing process of the light-emitting element or optical element, other materials can be used. Other materials that have the function of protecting the light-emitting element and the optical element can also be used.

[0241] For example, in the present invention, various substrates can be used to form light-emitting elements. There is no particular restriction on the type of substrate. As examples of the substrate, for example, semiconductor substrates (for example, single crystal substrates or silicon substrates), SOI substrates, glass substrates, quartz substrates, plastic substrates, metal substrates, stainless steel substrates, substrates with stainless steel foils, tungsten substrates, substrates with tungsten foils, flexible substrates, laminated films, paper containing fibrous materials or substrate films, etc. can be used. As examples of glass substrates, there are barium borosilicate glass, aluminum borosilicate glass, soda-lime glass, etc. As flexible substrates, laminated films, substrate films, etc., the following examples can be cited: plastics represented by polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyether sulfone (PES), and polytetrafluoroethylene (PTFE). Alternatively, as an example, resins such as acrylic resins can be cited. Alternatively, as an example, polypropylene, polyester, polyvinyl fluoride or polyvinyl chloride can be cited. Alternatively, polyamide, polyimide, aramid, epoxy resin, inorganic vapor-deposited film, paper, etc. can be cited as examples.

[0242] In addition, a flexible substrate may be used as a substrate, and a light-emitting element may be directly formed on the flexible substrate. Alternatively, a peeling layer may be provided between the substrate and the light-emitting element. The peeling layer may be used when a part or all of the light-emitting element is manufactured on the peeling layer, and then it is separated from the substrate and transferred to another substrate. In this case, the light-emitting element may also be transferred to a substrate with low heat resistance or a flexible substrate. Note that as the above-mentioned peeling layer, for example, a laminated structure of an inorganic film of a tungsten film and a silicon oxide film or a structure in which a resin film such as polyimide is formed on a substrate may be used.

[0243] That is, a light-emitting element can be formed using one substrate and then transferred to another substrate. As examples of substrates to which light-emitting elements are transferred, in addition to the above-mentioned substrates, there can be cited cellophane substrates, stone substrates, wood substrates, cloth substrates (including natural fibers (silk, cotton, linen), synthetic fibers (nylon, polyurethane, polyester) or regenerated fibers (acetate, cuprammonium, rayon, regenerated polyester), etc.), leather substrates, rubber substrates, etc. By using these substrates, it is possible to form light-emitting elements that are not easily damaged, light-emitting elements with high heat resistance, light-emitting elements that are lightweight, or light-emitting elements that are thin.

[0244] For example, a field effect transistor (FET) may be formed on any of the above substrates, and the light emitting element 110 may be formed on an electrode electrically connected to the FET. Thus, an active matrix display device in which driving of the light emitting element 110 is controlled by the FET can be manufactured.

[0245] In this embodiment, one embodiment of the present invention is described. In other embodiments, another embodiment of the present invention is described. Note that one embodiment of the present invention is not limited to the above example. That is, various modes of the invention are described in this embodiment and other embodiments, and thus one embodiment of the present invention is not limited to a specific mode. For example, although an example of applying one embodiment of the present invention to a light-emitting element is shown, one embodiment of the present invention is not limited to this. For example, depending on the situation or condition, one embodiment of the present invention may not be applied to a light-emitting element.

[0246] The structure described in this embodiment mode can be combined with the structure described in any other embodiment mode as appropriate.

[0247] (Implementation 4) In this embodiment, refer to Figure 3 An embodiment of a light-emitting element having a structure in which a plurality of light-emitting units are stacked (hereinafter also referred to as a stacked element) is described. The light-emitting element has a plurality of light-emitting units between a first electrode and a second electrode. Each light-emitting unit has the same structure as the EL layer 103 described in Embodiment 3. That is, it can be said that the light-emitting element described in Embodiment 3 has one light-emitting unit, while the light-emitting element described in this embodiment has a plurality of light-emitting units.

[0248] <Structural Example 1 of Light Emitting Device> exist Figure 3In the embodiment, a first light-emitting unit 521 and a second light-emitting unit 522 are stacked between the first electrode 510 and the second electrode 502, and a charge generation layer 523 is provided between the first light-emitting unit 521 and the second light-emitting unit 522. The first electrode 510 and the second electrode 502 correspond to the electrode 101 and the electrode 102 in Embodiment 3, respectively, and the materials described in Embodiment 3 can be used. In addition, the first light-emitting unit 521 and the second light-emitting unit 522 can have the same structure or different structures. For example, the first light-emitting unit 521 preferably uses the EL layer 103 described in Embodiment 3.

[0249] The charge generation layer 523 may have a structure in which an acceptor substance serving as an electron acceptor is added to a hole transport material, or a structure in which a donor substance serving as an electron donor is added to an electron transport material. Alternatively, these two structures may be stacked.

[0250] When the charge generation layer 523 includes a composite material of an organic compound and an acceptor substance, the composite material that can be used for the hole injection layer 111 shown in Embodiment 3 can be used as the composite material. As the organic compound, various compounds such as aromatic amine compounds, carbazole compounds, aromatic hydrocarbons, and polymer compounds (oligomers, dendrimers, polymers, etc.) can be used. As the organic compound, it is preferred to use an organic compound having a hole mobility of 1×10 -6 cm 2 / Vs or above. Note that as long as the hole transport property of the substance is higher than the electron transport property, substances other than these can be used. Because the composite material of the organic compound and the acceptor substance has good carrier injection and carrier transport properties, low voltage drive and low current drive can be achieved. Note that when the surface on the anode side of the light-emitting unit contacts the charge generation layer 523, the charge generation layer 523 can also be used as the hole injection layer or hole transport layer of the light-emitting unit, so the hole injection layer or hole transport layer may not be provided in the light-emitting unit. When the surface on the cathode side of the light-emitting unit contacts the charge generation layer 523, the charge generation layer 523 can also be used as the electron injection layer or electron transport layer of the light-emitting unit, so the electron injection layer or electron transport layer may not be provided in the light-emitting unit.

[0251] The charge generation layer 523 may also have a laminated structure of a layer containing a composite material of an organic compound and an acceptor substance and a layer containing other materials. For example, the charge generation layer 523 may also be formed using a layer containing a composite material of an organic compound and an acceptor substance in combination with a layer containing a compound selected from electron-donating substances and a compound with high electron transport properties. In addition, the charge generation layer 523 may also be formed using a layer containing a composite material of an organic compound and an acceptor substance in combination with a layer containing a transparent conductive film.

[0252] The charge generation layer 523 sandwiched between the first light-emitting unit 521 and the second light-emitting unit 522 may have any structure as long as it injects electrons into one light-emitting unit and injects holes into the other light-emitting unit when a voltage is applied between the first electrode 510 and the second electrode 502. Figure 3 When a voltage is applied so that the potential of the first electrode 510 is higher than the potential of the second electrode 502 , the charge generation layer 523 injects electrons into the first light-emitting unit 521 and injects holes into the second light-emitting unit 522 .

[0253] Note that from the viewpoint of light extraction efficiency, the charge generation layer 523 preferably has visible light transmittance (specifically, visible light transmittance of 40% or more). The charge generation layer 523 functions even if its conductivity is lower than that of the pair of electrodes (electrode 510 and electrode 502).

[0254] By forming the charge generation layer 523 using any of the above materials, an increase in driving voltage when a light-emitting layer is stacked can be suppressed.

[0255] The charge generation layer 523 may also have a laminated structure of a layer containing a composite material of an organic compound and a metal oxide and a layer containing other materials. For example, a layer containing a composite material of an organic compound and a metal oxide and a layer containing a compound selected from electron-donating substances and a compound having high electron transport properties may be combined. In addition, the charge generation layer 523 may also be formed using a layer containing a composite material of an organic compound and a metal oxide in combination with a transparent conductive film.

[0256] The charge generation layer 523 sandwiched between the first light-emitting unit 521 and the second light-emitting unit 522 may have any structure as long as it injects electrons into one light-emitting unit and injects holes into the other light-emitting unit when voltage is applied to the first electrode 510 and the second electrode 502. Figure 3 In the embodiment, the charge generation layer 523 may have a structure that injects electrons into the first light emitting unit 521 and injects holes into the second light emitting unit 522 when a voltage is applied so that the potential of the first electrode 510 is higher than that of the second electrode 502 .

[0257] Although a light-emitting element having two light-emitting units is described in this embodiment, a light-emitting element having three or more light-emitting units stacked may be similarly applied. By arranging a plurality of light-emitting units between a pair of electrodes in a manner separated by a charge generation layer, as in the light-emitting element of this embodiment, the light-emitting element can emit light at high brightness while maintaining a low current density, thereby realizing a light-emitting element with a long life. In addition, a light-emitting device that can be driven at a low voltage and has low power consumption can also be realized.

[0258] By making the emission colors of each light-emitting unit different, the desired color of light can be obtained from the entire light-emitting element. For example, by making the emission colors of the first light-emitting unit and the emission colors of the second light-emitting unit in a light-emitting element having two light-emitting units complementary, a light-emitting element that emits white light from the entire light-emitting element can be realized. Note that "complementary colors" refers to a color relationship in which achromatic colors are obtained when colors are mixed. That is, when light of colors in a complementary color relationship is mixed, white light can be obtained. In addition, the same is true for a light-emitting element having three light-emitting units. For example, when the emission color of the first light-emitting unit is red, the emission color of the second light-emitting unit is green, and the emission color of the third light-emitting unit is blue, white light can be emitted from the entire light-emitting element. In addition, by applying a light-emitting layer using a light-emitting center substance that exhibits phosphorescent emission in one light-emitting unit and applying a light-emitting layer using a light-emitting center substance that exhibits fluorescent emission in another light-emitting unit, both fluorescence and phosphorescence can be efficiently emitted from the light-emitting element. For example, by obtaining red and green phosphorescence from one light-emitting unit and blue fluorescence from another light-emitting unit, white light with high luminous efficiency can be obtained.

[0259] By using an organic compound of one embodiment of the present invention in a light-emitting element, a blue fluorescent element with low driving voltage, high efficiency and long life can be provided. Thus, low driving voltage, high efficiency, long life and color adjustment of the entire light-emitting element can be easily achieved.

[0260] This embodiment mode can be combined with any other embodiment mode as appropriate.

[0261] (Implementation 5) In this embodiment, reference Figure 4A and Figure 4B A light-emitting device using the light-emitting element described in Embodiment Modes 3 and 4 will be described.

[0262] Figure 4A is a top view of the light emitting device, Figure 4B is along Figure 4A AB and CD cut cross-sectional views in FIG. The light-emitting device includes a driving circuit portion (source side driving circuit) 601 for controlling the light emission of the light-emitting element, a pixel portion 602, and a driving circuit portion (gate side driving circuit) 603 indicated by a dotted line. In addition, reference numeral 604 is a sealing substrate, reference numeral 625 is a desiccant, and reference numeral 605 is a sealant. The inner side surrounded by the sealant 605 is a space 607.

[0263] Note that the guide wiring 608 is a wiring for transmitting signals input to the source side driver circuit 601 and the gate side driver circuit 603, and receives a video signal, a clock signal, a start signal, a reset signal, etc. from a flexible printed circuit (FPC) 609 used as an external input terminal. Although only the FPC is shown here, the FPC may also be mounted with a printed wiring board (PWB). The light-emitting device in this specification includes not only the light-emitting device body, but also a light-emitting device mounted with an FPC or a PWB.

[0264] Next, refer to Figure 4B The cross-sectional structure of the light emitting device is described below. A driver circuit section and a pixel section are formed on an element substrate 610. Here, a source side driver circuit 601 as a driver circuit section and one pixel in a pixel section 602 are shown.

[0265] In the source side driver circuit 601, a CMOS circuit combining an n-channel TFT 623 and a p-channel TFT 624 is formed. The driver circuit can also be formed using various CMOS circuits, PMOS circuits, or NMOS circuits. Although the driver integrated type in which the driver circuit is formed on the substrate is shown in this embodiment, the driver circuit does not necessarily need to be formed on the substrate and can also be formed outside the substrate.

[0266] The pixel portion 602 includes a plurality of pixels including a switching TFT 611, a current control TFT 612, and a first electrode 613 electrically connected to the drain of the current control TFT 612. Note that an insulator 614 is formed to cover the end of the first electrode 613. The insulator 614 can be formed using a positive photosensitive resin film.

[0267] In order to improve the coverage of the film formed on the insulator 614, the upper end or the lower end of the insulator 614 is formed into a curved surface having a curvature. For example, when a photosensitive acrylic resin is used as the material of the insulator 614, it is preferred that only the upper end of the insulator 614 has a curved surface. The curvature radius of the curved surface is preferably not less than 0.2 μm and not more than 0.3 μm. As the insulator 614, a negative photosensitive material or a positive photosensitive material can be used.

[0268] An EL layer 616 and a second electrode 617 are formed on the first electrode 613. As the material of the first electrode 613 used as an anode, a material having a large work function is preferably used. 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 wt% or more and 20 wt% or less of zinc oxide, a titanium nitride film, a chromium film, a tungsten film, a Zn film, a Pt film, etc., a stacked film including a titanium nitride film and a film having aluminum as a main component, and a three-layer structure film including a titanium nitride film, a film having aluminum as a main component, and a titanium nitride film can also be used. When a stacked structure is used, wiring resistance is also low, good ohmic contact can be obtained, and it can be used as an anode.

[0269] The EL layer 616 is formed by any of various methods such as vapor deposition using a vapor deposition mask, inkjet, and spin coating. As other materials included in the EL layer 616, low molecular weight compounds or high molecular weight compounds (including oligomers and dendrimers) may be used.

[0270] As a material of the second electrode 617 formed on the EL layer 616 and serving as a cathode, a material having a small work function (such as Al, Mg, Li, Ca, or alloys and compounds thereof, MgAg, MgIn, and AlLi) is preferably used. When light generated in the EL layer 616 is transmitted through the second electrode 617, a stacked layer including a relatively thin metal film and a transparent conductive film (such as ITO, indium oxide containing 2 wt% or more and 20 wt% or less of zinc oxide, indium tin oxide containing silicon, and zinc oxide (ZnO)) is preferably used as the second electrode 617.

[0271] Note that the light-emitting element 618 is formed of the first electrode 613, the EL layer 616, and the second electrode 617. The light-emitting element 618 preferably has a structure described in Embodiment 3 or Embodiment 4. In the light-emitting device of this embodiment, a pixel portion including a plurality of light-emitting elements may include both a light-emitting element having the structure described in Embodiment 3 or Embodiment 4 and a light-emitting element having a different structure.

[0272] The sealing substrate 604 and the element substrate 610 are bonded together by the sealant 605, and a light emitting element 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. The filler may be an inert gas (nitrogen, argon, etc.), a resin, and / or a desiccant.

[0273] As the sealant 605, an epoxy resin or glass powder is preferably used. These materials are preferably materials that do not allow moisture or oxygen to pass through as much as possible. As the sealing substrate 604, a glass substrate, a quartz substrate, or a plastic substrate formed of fiber reinforced plastic (FRP), polyvinyl fluoride (PVF), polyester, or acrylic resin can be used.

[0274] By the above method, a light-emitting device including the light-emitting element described in Embodiment Mode 3 and Embodiment Mode 4 can be obtained.

[0275] <Structural Example 2 of Light Emitting Device> Figure 5A and Figure 5B Each example shows a light-emitting device including a light-emitting element that emits white light and a coloring layer (color filter).

[0276] Figure 5A The substrate 1001, the base insulating film 1002, the gate insulating film 1003, the gate electrodes 1006, 1007, 1008, the first interlayer insulating film 1020, the second interlayer insulating film 1021, the peripheral portion 1042, the pixel portion 1040, the driver circuit portion 1041, the first electrode 1024W of the light emitting element, 1024R, 1024G, 1024B, a partition wall 1026, an EL layer 1028, a second electrode 1029 of a light-emitting element, a sealing substrate 1031, a sealant 1032, and the like.

[0277] exist Figure 5A , Figure 5B In the embodiment, the colored layers (red colored layer 1034R, green colored layer 1034G, blue colored layer 1034B) are provided on the transparent substrate 1033. In addition, a black layer (black matrix) 1035 may be provided. The transparent substrate 1033 provided with the colored layers and the black layer is aligned and fixed on the substrate 1001. Note that the colored layers and the black layer are covered by the cover layer 1036. Figure 5A In the embodiment, light emitted from some light-emitting layers does not pass through the coloring layers, while light emitted from other light-emitting layers passes through the coloring layers. Since light that does not pass through the coloring layers is white and light that passes through any of the coloring layers is red, blue, or green, an image can be presented with pixels of four colors.

[0278] Figure 5B An example is shown in which a red coloring layer 1034R, a green coloring layer 1034G, and a blue coloring layer 1034B are formed between the gate insulating film 1003 and the first interlayer insulating film 1020. Figure 5B As shown, a coloring layer may be provided between the substrate 1001 and the sealing substrate 1031.

[0279] Although the light-emitting device described above has a structure in which light is extracted from the substrate 1001 side where the TFT is formed (bottom emission type), it may have a structure in which light is extracted from the sealing substrate 1031 side (top emission type).

[0280] <Structural Example 3 of Light Emitting Device> Figure 6 1 is a cross-sectional view of a light-emitting device having a top emission structure. In this case, a substrate that does not allow light to pass through can be used as the substrate 1001. The process until the connection electrode for connecting the TFT and the anode of the light-emitting element is manufactured is performed in the same manner as the light-emitting device having a bottom emission structure. Then, a third interlayer insulating film 1037 is formed in a manner covering the electrode 1022. The insulating film may also have a planarization function. The third interlayer insulating film 1037 may be formed using the same material as the second interlayer insulating film 1021 or various other materials.

[0281] Although the lower electrodes 1025W, 1025R, 1025G, and 1025B of the light-emitting element are all anodes here, they may also be cathodes. Figure 6 In the light-emitting device having a top emission structure shown in the figure, the lower electrodes 1025W, 1025R, 1025G, and 1025B are preferably reflective electrodes. Note that the second electrode 1029 preferably has the function of emitting light and transmitting light. It is preferable to use a microcavity structure between the second electrode 1029 and the lower electrodes 1025W, 1025R, 1025G, and 1025B, thereby amplifying light of a specific wavelength. The EL layer 1028 is formed in a manner having the same structure as that described in Embodiment Modes 2 and 3, and is used to obtain white light emission.

[0282] exist Figure 5A , Figure 5B and Figure 6 In the embodiment of the present invention, a structure of an EL layer capable of obtaining white light emission may be realized by using a plurality of light-emitting layers or a plurality of light-emitting units. Note that the structure for obtaining white light emission is not limited to this.

[0283] In adopting Figure 6 In the case of the top emission structure shown, a sealing substrate 1031 provided with a coloring layer (red coloring layer 1034R, green coloring layer 1034G, blue coloring layer 1034B) can be used for sealing. The sealing substrate 1031 can also be provided with a black layer (black matrix) 1035 located between pixels. The coloring layer (red coloring layer 1034R, green coloring layer 1034G, blue coloring layer 1034B) and the black layer (black matrix) can also be covered by a cover layer. Note that a light-transmitting substrate is used as the sealing substrate 1031.

[0284] Although an example of full-color display using four colors of red, green, blue, and white is shown here, it is not limited to this, and full-color display may be performed using three colors of red, green, and blue or four colors of red, green, blue, and yellow.

[0285] By the above method, a light-emitting device including the light-emitting element described in Embodiment Mode 3 and Embodiment Mode 4 can be obtained.

[0286] This embodiment mode can be combined with any other embodiment mode as appropriate.

[0287] (Implementation method 6) In this embodiment, a specific example of a display device including the light-emitting element described in Embodiment 3 and Embodiment 4 is described. The display device described below includes two elements, a reflective liquid crystal element and a light-emitting element. The display device can display in a transmission mode and a reflection mode. As the light-emitting element, the light-emitting element described in Embodiment 3 and Embodiment 4 is preferably used.

[0288] [Structural Example 1 of Display Device] Fig. 7A 362 is a block diagram showing an example of the structure of the display device 400. The display device 400 includes a plurality of pixels 410 arranged in a matrix in the display portion 362. The display device 400 also includes a circuit GD and a circuit SD. In addition, the display device 400 includes a plurality of wirings G1, a plurality of wirings G2, a plurality of wirings ANO, and a plurality of wirings CSCOM electrically connected to the plurality of pixels 410 arranged in the direction R and the circuit GD. In addition, the display device 400 includes a plurality of wirings S1 and a plurality of wirings S2 electrically connected to the plurality of pixels 410 arranged in the direction C and the circuit SD.

[0289] The pixel 410 includes a reflective liquid crystal element and a light emitting element. In the pixel 410, the liquid crystal element and the light emitting element partially overlap each other.

[0290] Figure 7B1 4 shows an example of the structure of the electrode 311b included in the pixel 410. The electrode 311b is used as a reflective electrode of the liquid crystal element in the pixel 410. The electrode 311b has an opening 451.

[0291] exist Figure 7B1 In FIG. 4 , the light emitting element 360 located in the region overlapping with the electrode 311 b is shown by a dotted line. The light emitting element 360 overlaps with the opening 451 included in the electrode 311 b. Thus, the light emitted by the light emitting element 360 is emitted to the display surface side through the opening 451.

[0292] exist Figure 7B1 In the example, adjacent pixels 410 in the direction R correspond to different colors. Figure 7B1As shown, it is preferred that the openings 451 are provided at different positions of the electrode 311b in two pixels adjacent in the direction R so as not to be provided in a row. Thus, the two light-emitting elements 360 can be separately arranged, thereby suppressing the light emitted by the light-emitting element 360 from entering the coloring layer in the adjacent pixel 410 (this phenomenon is also called crosstalk). In addition, since the two adjacent light-emitting elements 360 can be separately arranged, even if the EL layers of the light-emitting elements 360 are manufactured separately using a shadow mask or the like, a high-resolution display device can be realized.

[0293] Alternatively, you can use Figure 7B2 Arrangement shown.

[0294] When the ratio of the total area of ​​the openings 451 to the total area other than the openings is too large, the display using the liquid crystal element becomes dark. When the ratio of the total area of ​​the openings 451 to the total area other than the openings is too small, the display using the light emitting element 360 becomes dark.

[0295] When the area of ​​the opening 451 in the electrode 311 b used as a reflective electrode is too small, the extraction efficiency of light emitted from the light emitting element 360 becomes low.

[0296] The opening 451 may have a polygonal, quadrilateral, elliptical, circular, cross-shaped, stripe-shaped, slit-shaped, or lattice-shaped shape. The opening 451 may be arranged close to adjacent pixels. Preferably, the opening 451 is arranged close to other pixels displaying the same color, thereby suppressing the generation of crosstalk.

[0297] [Circuit structure example] Figure 8 is a circuit diagram showing a structural example of the pixel 410. Figure 8 Two pixels 410 are shown as being adjacent.

[0298] The pixel 410 includes a switch SW1, a capacitor C1, a liquid crystal element 340, a switch SW2, a transistor M, a capacitor C2, a light emitting element 360, etc. The pixel 410 is electrically connected to the wiring G1, the wiring G2, the wiring ANO, the wiring CSCOM, the wiring S1, and the wiring S2. Figure 8 Also shown are a wiring VCOM1 electrically connected to the liquid crystal element 340 and a wiring VCOM2 electrically connected to the light emitting element 360 .

[0299] Figure 8 An example in which transistors are used for the switch SW1 and the switch SW2 is shown.

[0300] The gate of the switch SW1 is connected to the wiring G1. One of the source and the drain of the switch SW1 is connected to the wiring S1, and the other of the source and the drain is connected to one electrode of the capacitor C1 and one electrode of the liquid crystal element 340. The other electrode of the capacitor C1 is connected to the wiring CSCOM. The other electrode of the liquid crystal element 340 is connected to the wiring VCOM1.

[0301] The gate of the switch SW2 is connected to the wiring G2. One of the source and the drain of the switch SW2 is connected to the wiring S2, and the other of the source and the drain is connected to one electrode of the capacitor C2 and the gate of the transistor M. The other electrode of the capacitor C2 is connected to one of the source and the drain of the transistor M and the wiring ANO. The other of the source and the drain of the transistor M is connected to one electrode of the light emitting element 360. The other electrode of the light emitting element 360 is connected to the wiring VCOM2.

[0302] Figure 8 The example in which the transistor M includes two gates connected to each other with a semiconductor sandwiched therebetween is shown. This structure can increase the amount of current that can flow through the transistor M.

[0303] The wiring G1 may be supplied with a signal for controlling the switch SW1 to be in an on / off state. The wiring VCOM1 may be supplied with a predetermined potential. The wiring S1 may be supplied with a signal for controlling the alignment state of the liquid crystal included in the liquid crystal element 340. The wiring CSCOM may be supplied with a predetermined potential.

[0304] The wiring G2 may be supplied with a signal for controlling the switch SW2 to be turned on or off. The wiring VCOM2 and the wiring ANO may be supplied with a potential for generating a potential difference for causing the light emitting element 360 to emit light. The wiring S2 may be supplied with a signal for controlling the conduction state of the transistor M.

[0305] exist Figure 8 In the pixel 410 shown, for example, when displaying in the reflective mode, it can be driven by the signal supplied to the wiring G1 and the wiring S1, and display can be performed by optical modulation of the liquid crystal element 340. When displaying in the transmissive mode, it can be driven by the signal supplied to the wiring G2 and the wiring S2, and display can be performed by causing the light emitting element 360 to emit light. When driving in both modes, it can be driven by the signal supplied to the wiring G1, the wiring G2, the wiring S1, and the wiring S2.

[0306] Although Figure 8 Although an example is shown in which one liquid crystal element 340 and one light emitting element 360 are provided in one pixel 410 , one embodiment of the present invention is not limited to this. Fig.9AAn example is shown in which one liquid crystal element 340 and four light-emitting elements 360 (light-emitting elements 360r, 360g, 360b, and 360w) are provided in one pixel 410. Figure 8 different, Fig.9A The pixel 410 shown can perform full color display using one pixel.

[0307] Apart from Figure 8 In addition to the example, Fig.9A The pixel 410 in is connected to the wiring G3 and the wiring S3.

[0308] exist Fig.9A In the example shown, for example, as the four light emitting elements 360, light emitting elements that respectively emit red (R), green (G), blue (B), and white (W) can be used. In addition, a reflective liquid crystal element that emits white light can be used as the liquid crystal element 340. Thus, when displaying in the reflective mode, white display with high reflectivity can be performed. When displaying in the transmissive mode, display with high color rendering can be performed with low power consumption.

[0309] Fig. 9B 4 shows a structural example of a pixel 410. The pixel 410 includes a light emitting element 360w overlapping with an opening in an electrode 311, and light emitting elements 360r, 360g, and 360b arranged around the electrode 311. The light emitting elements 360r, 360g, and 360b preferably have almost the same light emitting area.

[0310] [Structural Example 2 of Display Device] Fig.10 3 is a perspective view of a display device 300 according to an embodiment of the present invention. In the display device 300, a substrate 351 and a substrate 361 are bonded together. Fig.10 In FIG. 3 , the substrate 361 is indicated by a dotted line.

[0311] The display device 300 includes a display portion 362, a circuit portion 364, wiring 365, a circuit portion 366, wiring 367, and the like. The substrate 351 is provided with, for example, the circuit portion 364, wiring 365, a circuit portion 366, wiring 367, and an electrode 311b used as a pixel electrode. Fig.10 In the embodiment, IC373, FPC372, IC375 and FPC374 are mounted on substrate 351. Fig.10 The structure shown is referred to as a display module including a display device 300 , IC 373 , FPC 372 , IC 375 , and FPC 374 .

[0312] As the circuit portion 364 , for example, a circuit used as a scan line driver circuit can be used.

[0313] The wiring 365 has a function of supplying signals and power to the display portion and the circuit portion 364. The signals and power are input to the wiring 365 from the outside via the FPC 372 or from the IC 373.

[0314] Fig.10 An example of providing IC373 on substrate 351 by using a chip on glass (COG) method or the like is shown. As IC373, for example, an IC having a function such as a scan line driver circuit or a signal line driver circuit can be used. Note that when the display device 300 has a circuit used as a scan line driver circuit or a signal line driver circuit, and the circuit used as a scan line driver circuit or a signal line driver circuit is provided externally and a signal for driving the display device 300 is input through FPC372, IC373 may not be provided. Alternatively, IC373 may be mounted on FPC372 by using a chip on film (COF) method or the like.

[0315] Fig.10 FIG. 1 is an enlarged view of a part of the display portion 362. A plurality of electrodes 311b included in the display element are arranged in a matrix in the display portion 362. The electrodes 311b have a function of reflecting visible light and are used as a reflective electrode of a liquid crystal element 340 described below.

[0316] like Fig.10 As shown, the electrode 311b has an opening. A light emitting element 360 is provided on the side closer to the substrate 351 than the electrode 311b. Light emitted from the light emitting element 360 is emitted to the substrate 361 side through the opening of the electrode 311b.

[0317] Fig.11 Show that Fig.10 The display device shown is an example of a cross-section of a portion of the area including FPC372, a portion of the area including the circuit portion 364, a portion of the area including the display portion 362, a portion of the area including the circuit portion 366, and a portion of the area including FPC374.

[0318] Fig.11 The display device shown has a structure in which a display panel 700 and a display panel 800 are stacked. The display panel 700 includes a resin layer 701 and a resin layer 702. The display panel 800 includes a resin layer 201 and a resin layer 202. The resin layer 702 and the resin layer 201 are bonded by an adhesive layer 50. The resin layer 701 is bonded to the substrate 351 by the adhesive layer 51. The resin layer 202 is bonded to the substrate 361 by the adhesive layer 52.

[0319] [Display panel 700] The display panel 700 includes a resin layer 701, an insulating layer 478, multiple transistors, a capacitor 405, an insulating layer 411, an insulating layer 412, an insulating layer 413, an insulating layer 414, an insulating layer 415, a light-emitting element 360, a spacer 416, an adhesive layer 417, a coloring layer 425, a light-shielding layer 426, an insulating layer 476 and a resin layer 702.

[0320] The circuit portion 364 includes a transistor 401. The display portion 362 includes a transistor 402 and a transistor 403.

[0321] Each transistor includes a gate, an insulating layer 411, a semiconductor layer, a source, and a drain. The gate and the semiconductor layer overlap each other via the insulating layer 411. A portion of the insulating layer 411 is used as a gate insulating layer, and another portion of the insulating layer 411 is used as a dielectric of the capacitor 405. The conductive layer used as the source or drain of the transistor 402 is also used as one electrode of the capacitor 405.

[0322] Fig.11 The transistor shown has a bottom gate structure. The transistor structures may be different in the circuit portion 364 and the display portion 362. The circuit portion 364 and the display portion 362 may each include a plurality of transistors.

[0323] The capacitor 405 includes a pair of electrodes and a dielectric therebetween. The capacitor 405 includes a conductive layer formed using the same material and the same process as a gate of a transistor and a conductive layer formed using the same material and the same process as a source and a drain of a transistor.

[0324] The insulating layer 412, the insulating layer 413, and the insulating layer 414 are respectively provided in a manner of covering the transistors, etc. There is no particular limitation on the number of insulating layers covering the transistors, etc. The insulating layer 414 is used as a planarization layer. It is preferred that at least one of the insulating layer 412, the insulating layer 413, and the insulating layer 414 is formed using a material in which impurities such as water and hydrogen are not easily diffused. The diffusion of impurities from the outside into the transistor can be effectively suppressed, thereby improving the reliability of the display device.

[0325] When an organic compound is used as the insulating layer 414, there is a concern that impurities such as moisture may enter the light emitting element 360 from outside the display device through the insulating layer 414 exposed at the end of the display device. Deterioration of the light emitting element 360 due to the entry of impurities may cause degradation of the display device. Fig.11 As shown, the insulating layer 414 is preferably not located at the end of the display device. Fig.11 In the structure, since the insulating layer using an organic compound is not located at the end of the display device, it is possible to suppress the entry of impurities into the light-emitting element 360.

[0326] The light-emitting element 360 includes an electrode 421, an EL layer 422, and an electrode 423. The light-emitting element 360 may include an optical adjustment layer 424. The light-emitting element 360 has a top emission structure that emits light toward the coloring layer 425 side.

[0327] By arranging transistors, capacitors, wirings, and the like so as to overlap with the light-emitting region of the light-emitting element 360 , the aperture ratio of the display portion 362 can be increased.

[0328] One of the electrode 421 and the electrode 423 is used as an anode, and the other is used as a cathode. When a voltage higher than the threshold voltage of the light-emitting element 360 is applied between the electrode 421 and the electrode 423, holes are injected from the anode side and electrons are injected from the cathode side into the EL layer 422. The injected electrons and holes are recombined in the EL layer 422, and the light-emitting substance contained in the EL layer 422 emits light.

[0329] The electrode 421 is directly electrically connected to the source or drain of the transistor 403 or is connected to each other through a conductive layer. The electrode 421 is used as a pixel electrode and is provided in each light emitting element 360. Two adjacent electrodes 421 are electrically insulated by an insulating layer 415.

[0330] The electrode 423 used as a common electrode is commonly used by a plurality of light emitting elements 360. The electrode 423 is supplied with a constant potential.

[0331] The light emitting element 360 overlaps with the coloring layer 425 via the adhesive layer 417. The spacer 416 overlaps with the light shielding layer 426 via the adhesive layer 417. Fig.11 4 shows a case where there is a gap between the electrode 423 and the light shielding layer 426, but the electrode 423 and the light shielding layer 426 may be in contact with each other. Fig.11 In the illustrated structure, the spacer 416 is disposed on the substrate 351 side, but the spacer 416 may be disposed on the substrate 361 side (for example, on a side closer to the substrate 361 than the light shielding layer 426 ).

[0332] By using a combination of a color filter (coloring layer 425) and a microcavity structure (optical adjustment layer 424), light with high color purity can be extracted from the display device. The thickness of the optical adjustment layer 424 is changed according to the color of each pixel.

[0333] The colored layer 425 is a colored layer that transmits light in a specific wavelength region. For example, a color filter that transmits light in a red, green, blue, or yellow wavelength region can be used.

[0334] Note that an embodiment of the present invention is not limited to the color filter method, and an independent color development method, a color conversion method, a quantum dot method, etc. may be used.

[0335] The light shielding layer 426 is provided between adjacent coloring layers 425. The light shielding layer 426 shields the light emitted by the adjacent light emitting elements 360, thereby suppressing color mixing between the adjacent light emitting elements 360. Here, by providing the coloring layer 425 in such a manner that its end overlaps with the light shielding layer 426, light leakage can be suppressed. As the light shielding layer 426, a material that shields the light emitted by the light emitting element 360 can be used. Note that by providing the light shielding layer 426 in a region outside the display portion 362 such as the circuit portion 364, unintentional light leakage due to waveguide light or the like can be suppressed, which is preferred.

[0336] An insulating layer 478 is formed on one surface of the resin layer 701. An insulating layer 476 is formed on one surface of the resin layer 702. It is preferable to use a highly moisture-proof film as the insulating layer 476 and the insulating layer 478. By arranging the light-emitting element 360 and the transistor between a pair of highly moisture-proof insulating layers, it is possible to suppress the intrusion of impurities such as water into these elements, thereby improving the reliability of the display device, which is preferable.

[0337] As the insulating film with high moisture resistance, films containing nitrogen and silicon (e.g., silicon nitride film and silicon nitride oxide film) and films containing nitrogen and aluminum (e.g., aluminum nitride film) can be cited. In addition, silicon oxide film, silicon oxynitride film, aluminum oxide film, etc. can also be used.

[0338] For example, the water vapor permeability of a highly moisture-proof insulating film is 1×10 -5 [g / (m 2 ·day)] or less, preferably 1×10 -6 [g / (m 2 ·day)] or less, more preferably 1×10 -7 [g / (m 2 ·day)] or less, more preferably 1×10 -8 [g / (m 2 ·day)] or less.

[0339] The connection portion 406 includes a wiring 365. The wiring 365 can be formed using the same material and the same process as the source and drain of the transistor. The connection portion 406 is electrically connected to an external input terminal that transmits a signal and a potential from the outside to the circuit portion 364. Here, an example of providing an FPC 372 as an external input terminal is shown. The FPC 372 and the connection portion 406 are electrically connected through a connection layer 419.

[0340] The connection layer 419 can be formed using various anisotropic conductive films (ACFs) and anisotropic conductive pastes (ACPs).

[0341] The above is the description of the display panel 700 .

[0342] [Display panel 800] The display panel 800 is a reflective liquid crystal display device that adopts a vertical electric field method.

[0343] The display panel 800 includes a resin layer 201, an insulating layer 578, multiple transistors, a capacitor 505, a wiring 367, an insulating layer 511, an insulating layer 512, an insulating layer 513, an insulating layer 514, a liquid crystal element 529, an orientation film 564a, an orientation film 564b, an adhesive layer 517, an insulating layer 576 and a resin layer 202.

[0344] The resin layer 201 and the resin layer 202 are bonded together by an adhesive layer 517. Liquid crystal 563 is sealed in a region surrounded by the resin layer 201, the resin layer 202, and the adhesive layer 517. A polarizing plate 599 is located on the outer side of the substrate 361.

[0345] The liquid crystal element 529 includes an electrode 311b, an electrode 562, and a liquid crystal 563. The electrode 311b is used as a pixel electrode. The electrode 562 is used as a common electrode. By utilizing the electric field generated between the electrode 311b and the electrode 562, the orientation of the liquid crystal 563 can be controlled. An orientation film 564a is provided between the liquid crystal 563 and the electrode 311b. An orientation film 564b is provided between the liquid crystal 563 and the electrode 562.

[0346] An insulating layer 576, an electrode 562, an alignment film 564b, and the like are provided over the resin layer 202.

[0347] An electrode 311 b , an alignment film 564 a , a transistor 501 , a transistor 503 , a capacitor 505 , a connection portion 506 , a wiring 367 , and the like are provided on the resin layer 201 .

[0348] Insulating layers such as an insulating layer 511 , an insulating layer 512 , an insulating layer 513 , and an insulating layer 514 are provided over the resin layer 201 .

[0349] Note that a portion of the conductive layer which is not electrically connected to the electrode 311b and which serves as a source or a drain of the transistor 503 can also serve as a portion of a signal line. A conductive layer which serves as a gate of the transistor 503 can also serve as a portion of a scan line.

[0350] Fig.11 A structure without a coloring layer is shown as an example of the display portion 362. Thus, the liquid crystal element 529 is an element that performs black and white grayscale display.

[0351] Fig.11 An example of a circuit portion 366 provided with a transistor 501 is shown.

[0352] At least one of the insulating layer 512 and the insulating layer 513 covering each transistor is preferably formed using a material in which impurities such as water and hydrogen are not easily diffused.

[0353] An electrode 311 b is provided over the insulating layer 514 . The electrode 311 b is electrically connected to one of the source and the drain of the transistor 503 through an opening formed in the insulating layer 514 , the insulating layer 513 , the insulating layer 512 , or the like. The electrode 311 b is electrically connected to one electrode of the capacitor 505 .

[0354] Since the display panel 800 is a reflective liquid crystal display device, a conductive material that reflects visible light is used for the electrode 311 b , and a conductive material that transmits visible light is used for the electrode 562 .

[0355] As a conductive material that transmits visible light, for example, a material containing one selected from indium (In), zinc (Zn), and tin (Sn) is preferably used. Specifically, indium oxide, indium tin oxide (ITO), indium zinc oxide, indium oxide containing tungsten oxide, indium zinc oxide containing tungsten oxide, indium oxide containing titanium oxide, indium tin oxide containing titanium oxide, indium tin oxide containing silicon oxide (ITSO), zinc oxide, zinc oxide containing gallium, etc. can be cited. Note that a film containing graphene can also be used. The film containing graphene can be formed, for example, by reducing a film containing graphene oxide.

[0356] As the conductive material reflecting visible light, for example, aluminum, silver or alloys containing these metal materials can be cited. In addition, metal materials such as gold, platinum, nickel, tungsten, chromium, molybdenum, iron, cobalt, copper or palladium or alloys containing these metal materials can be used. In addition, lanthanum, neodymium or germanium can also be added to the above-mentioned metal materials or alloys. In addition, alloys containing aluminum (aluminum alloys) such as aluminum and titanium alloys, aluminum and nickel alloys, aluminum and neodymium alloys, aluminum, nickel and lanthanum alloys (Al-Ni-La), silver and copper alloys, silver, palladium and copper alloys (Ag-Pd-Cu, also denoted as APC) or silver and magnesium alloys can also be used.

[0357] As the polarizer 599, a linear polarizer or a circular polarizer can be used. As the circular polarizer, for example, a stack including a linear polarizer and a quarter-wave phase difference plate can be used. This structure can suppress the reflection of external light. The desired contrast is achieved by adjusting the cell gap, orientation, and drive voltage of the liquid crystal element used for the liquid crystal element 529 according to the type of the polarizer 599.

[0358] The electrode 562 is electrically connected to the conductive layer provided on the resin layer 201 side through the connector 543 near the end of the resin layer 202. Thus, a potential or a signal can be supplied to the electrode 562 from the FPC 374 or IC provided on the resin layer 201 side.

[0359] As the connector 543, for example, conductive particles can be used. As the conductive particles, particles of organic resin or silicon dioxide, etc., whose surfaces are covered with a metal material, can be used. As the metal material, nickel or gold is preferably used because it can reduce the contact resistance. In addition, it is preferable to use particles in which two or more metal materials are layered, such as nickel covered with gold. As the connector 543, it is preferable to use a material that can be elastically deformed or plastically deformed. In this case, the connector 543 of the conductive particles sometimes becomes Fig.11 The flattened shape can increase the contact area between the connection body 543 and the conductive layer electrically connected to the connection body 543, thereby reducing the contact resistance and preventing problems such as poor contact from occurring.

[0360] The connector 543 is preferably disposed so as to be covered by the adhesive layer 517. For example, the connector 543 may be dispersed in advance in the adhesive layer 517 before being cured.

[0361] A connection portion 506 is provided in a region near the end of the resin layer 201. The connection portion 506 is electrically connected to the FPC 374 via a connection layer 519. Fig.11 In the example of the structure shown, the connection portion 506 is formed by laminating a part of the wiring 367 and a conductive layer obtained by processing the same conductive film as the electrode 311b.

[0362] The above is the description of the display panel 800 .

[0363] [Display components] As a display element included in the first pixel located on one side of the display surface, an element that reflects external light for display can be used. Because this element does not include a light source, the power consumption during display can be minimized. As a display element included in the first pixel, a reflective liquid crystal element can be typically used. Alternatively, as a display element included in the first pixel, not only a shutter-type micro-electromechanical system (MEMS) element, an optical interference-type MEMS element can be used, but also elements using a microcapsule method, an electrophoresis method, an electrowetting method, an electronic powder fluid (registered trademark) method, etc. can be used.

[0364] As a display element included in the second pixel located on the opposite side of the display surface, an element that includes a light source and uses the light from the light source for display can be used. Since the brightness and chromaticity of the light emitted by this pixel are not affected by external light, this pixel can display with high color reproducibility (wide color gamut) and high contrast, that is, a vivid display can be performed. As a display element included in the second pixel, for example, a self-luminous light-emitting element such as an organic light-emitting diode (OLED), a light-emitting diode (LED), a quantum dot light-emitting diode (QLED), etc. can be used. Alternatively, as a display element included in the second pixel, a backlight source as a light source and a transmissive liquid crystal element that controls the light transmittance from the backlight source can also be used in combination.

[0365] [Liquid crystal element] As the liquid crystal element, an element using a vertical alignment (VA) mode can be used. As the vertical alignment mode, a multi-quadrant vertical alignment (MVA) mode, a vertical alignment configuration (PVA) mode, an advanced super visual (ASV) mode, etc. can be used.

[0366] As a liquid crystal element, various modes can be used. For example, in addition to the VA mode, liquid crystal elements such as twisted nematic (TN) mode, in-plane switching (IPS) mode, fringe field switching (FFS) mode, axisymmetric microcell (ASM) mode, optically compensated bend (OCB) mode, ferroelectric liquid crystal (FLC) mode, antiferroelectric liquid crystal (AFLC) mode, etc. can be used.

[0367] Liquid crystal elements use the optical modulation effect of liquid crystals to control the transmission or non-transmission of light. The optical modulation effect of liquid crystals is controlled by the electric field (including lateral electric field, longitudinal electric field or tilted electric field) applied to the liquid crystal. As liquid crystals used in liquid crystal elements, thermotropic liquid crystals, low molecular liquid crystals, polymer liquid crystals, polymer dispersed liquid crystals (PDLC), ferroelectric liquid crystals, antiferroelectric liquid crystals, etc. can be used. These liquid crystal materials present cholesteric phases, smectic phases, cubic phases, chiral nematic phases, isotropic phases, etc. depending on the conditions.

[0368] As the liquid crystal material, either positive liquid crystal or negative liquid crystal can be used, and an appropriate liquid crystal material can be adopted according to the applicable mode or design.

[0369] In order to control the orientation of the liquid crystal, an orientation film can be provided. In the case of adopting the transverse electric field method, a liquid crystal exhibiting a blue phase without an orientation film can also be used. The blue phase is a type of liquid crystal phase, which refers to the phase that appears just before the transition from the cholesteric phase to the homogeneous phase when the temperature of the cholesteric liquid crystal is raised. Since the blue phase only appears within a narrow temperature range, a liquid crystal composition in which a chiral agent is mixed at a few wt% or more is used in the liquid crystal layer to expand the temperature range. The liquid crystal composition containing a liquid crystal exhibiting a blue phase and a chiral agent has a fast response speed and is optically isotropic. In addition, the liquid crystal composition containing a liquid crystal exhibiting a blue phase and a chiral agent does not require an orientation treatment and has a small viewing angle dependence. Since there is no need to provide an orientation film and no friction treatment is required, electrostatic damage caused by the friction treatment can be prevented, and defects and damage to the liquid crystal display device in the manufacturing process can be reduced.

[0370] When a reflective liquid crystal element is used, a polarizing plate is disposed on the display surface side. In addition, when a light diffusion plate is additionally disposed on the display surface side, visibility can be improved, which is preferred.

[0371] [Light-emitting element] The light-emitting element can use an element capable of self-luminescence, and the category of the light-emitting element includes an element whose brightness is controlled by current or voltage. For example, an LED, a QLED, an organic EL element, or an inorganic EL element can be used, but it is preferred to use any of the light-emitting elements described in Embodiment Modes 3 and 4.

[0372] In this embodiment, in particular, the light-emitting element preferably has a top emission structure. A conductive film that transmits visible light is used as an electrode on the light extraction side. A conductive film that reflects visible light is preferably used as an electrode on the side that does not extract light. The light-emitting element may be a single element including one EL layer or a tandem element in which a plurality of EL layers are stacked via a charge generation layer.

[0373] The EL layer includes at least a light-emitting layer. In addition to the light-emitting layer, the EL layer may include a layer or multiple layers containing any one of a substance with high hole injection property, a substance with high hole transport property, a hole blocking material, a substance with high electron transport property, a substance with high electron injection property, or a bipolar substance (a substance with high electron transport property and hole transport property).

[0374] The EL layer can use the low molecular weight compounds, high molecular weight compounds, and inorganic compounds listed in Embodiment 3. The layers included in the EL layer can be formed by any of the following methods: vapor deposition (including vacuum vapor deposition), transfer, printing, inkjet, coating, and the like.

[0375] [Adhesive layer] As the adhesive layer, various curing adhesives such as light curing adhesives such as ultraviolet curing adhesives, reaction curing adhesives, heat curing adhesives, anaerobic adhesives, etc. can be used. As these adhesives, epoxy resins, acrylic resins, silicone resins, phenolic resins, polyimide resins, imide resins, polyvinyl chloride (PVC) resins, polyvinyl butyral (PVB) resins, ethylene-vinyl acetate (EVA) resins, etc. can be cited. In particular, it is preferred to use materials with low moisture permeability such as epoxy resins. In addition, two-liquid mixed resins can also be used. In addition, adhesive sheets, etc. can also be used.

[0376] In addition, the above-mentioned resin may also contain a desiccant. For example, a substance that absorbs moisture by chemical adsorption, such as an oxide of an alkaline earth metal (calcium oxide or barium oxide, etc.) may be used. Alternatively, a substance that absorbs moisture by physical adsorption, such as zeolite or silica gel, may be used. When a desiccant is contained in the resin, it is possible to suppress impurities such as moisture from entering the element, thereby improving the reliability of the display panel, so it is preferred.

[0377] In addition, by mixing a filler or a light scattering member having a high refractive index into the above resin, the light extraction efficiency can be improved. For example, titanium oxide, barium oxide, zeolite, zirconium, etc. can be used.

[0378] [Connection Layer] As the connection layer, an anisotropic conductive film (ACF), anisotropic conductive paste (ACP), or the like can be used.

[0379] [Coloring Layer] Examples of materials that can be used for the coloring layer include metal materials, resin materials, and resin materials containing a pigment or a dye.

[0380] [Light-shielding layer] As materials that can be used for the light-shielding layer, carbon black, titanium black, metals, metal oxides, and composite oxides containing a solid solution of multiple metal oxides can be cited. The light-shielding layer can also be a film containing a resin material or a thin film containing an inorganic material such as a metal. In addition, a laminated film of a film containing a material of a coloring layer can also be used for the light-shielding layer. For example, a laminated structure of a film containing a material of a coloring layer for transmitting light of a certain color and a film containing a material of a coloring layer for transmitting light of other colors can be used. By making the material of the coloring layer and the light-shielding layer the same, in addition to being able to use the same equipment, the process can also be simplified, so it is preferred.

[0381] The structure described in this embodiment can be combined with the structure described in other embodiment modes as appropriate.

[0382] (Implementation 7) In this embodiment, an electronic device including the light-emitting element described in Embodiment 3 and Embodiment 4 is described. The light-emitting element described in Embodiment 3 and Embodiment 4 has a compound containing one embodiment of the present invention, and is therefore a light-emitting element with reduced power consumption and high reliability. As a result, the electronic device described in this embodiment can include a display portion with reduced power consumption and high reliability. In addition, since the light-emitting element described in Embodiment 3 and Embodiment 4 is a light-emitting element with a low driving voltage, an electronic device with a low driving voltage can be realized.

[0383] Examples of electronic devices including the light-emitting element include television sets (also referred to as television sets or television receivers), displays for computers, etc., cameras such as digital cameras and digital imagers, digital photo frames, mobile phones (also referred to as mobile phones or mobile phone devices), portable game consoles, portable information terminals, sound reproduction devices, large-scale game consoles such as pinball machines, etc. Specific examples of these electronic devices are shown below.

[0384] Fig. 12A An example of a television device is shown. In the television device, a display portion 7103 is assembled in a frame 7101. In addition, the frame 7101 is supported by a bracket 7105. The display portion 7103 can display an image and includes the same light-emitting elements as those of Embodiment Mode 3 or Embodiment Mode 4 and arranged in a matrix. Since each of the light-emitting elements includes an organic compound of an embodiment of the present invention, it can have high luminous efficiency and low driving voltage. Therefore, the television device including the display portion 7103 formed using the light-emitting element can have low power consumption and low driving voltage.

[0385] The television device can be operated by using an operation switch of the housing 7101 or a remote controller 7110 provided separately. Channels and volume can be controlled by using operation keys 7109 of the remote controller 7110, thereby controlling an image displayed on the display portion 7103. The remote controller 7110 may be provided with a display portion 7107 for displaying data output from the remote controller 7110.

[0386] Note that the television set is equipped with a receiver, a modem, etc. General television broadcasts can be received through the receiver. Furthermore, the television set is connected to a wired or wireless communication network through a modem, and can perform one-way (from a sender to a receiver) or two-way (between a sender and a receiver or between receivers, etc.) information communication.

[0387] Fig. 12B7204, a computer is shown, which includes a main body 7201, a frame 7202, a display portion 7203, a keyboard 7204, an external connection port 7205, a pointing device 7206, and the like. Note that the computer is manufactured by arranging the same light-emitting elements as those in Embodiment 3 or Embodiment 4 in a matrix shape and using them in the display portion 7203. Since the light-emitting elements each contain a compound of one embodiment of the present invention, they can have high luminous efficiency and low driving voltage. Therefore, a computer including a display portion 7203 formed using the light-emitting elements can have low power consumption and low driving voltage.

[0388] Fig. 12C A portable game console is shown, which includes two frames, namely, frame 7301 and frame 7302, and is connected to a connecting portion 7303 so that the portable game console can be opened and closed. A display portion 7304 manufactured by arranging light-emitting elements similar to those of Embodiment Modes 3 and 4 in a matrix is ​​assembled in frame 7301, and a display portion 7305 is assembled in frame 7302. In addition, Fig. 12C The portable game console shown in the figure further includes a speaker portion 7306, a recording medium insertion portion 7307, an LED lamp 7308, an input unit (operation keys 7309, a connection terminal 7310, a sensor 7311 (including a function of measuring the following factors: force, displacement, position, speed, acceleration, angular velocity, number of rotations, distance, light, liquid, magnetism, temperature, chemical substance, sound, time, hardness, electric field, current, voltage, electricity, radiation, flow, humidity, slope, vibration, smell or infrared), a microphone 7312), etc. Of course, the structure of the portable game console is not limited to the above structure, as long as a display portion manufactured by arranging the light-emitting elements shown in embodiments 3 and 4 in a matrix is ​​used in one or both of the display portion 7304 and the display portion 7305, and a structure in which other auxiliary devices are appropriately provided can be adopted. Fig. 12C The portable game machine shown has the following functions: reading out programs or data stored in a recording medium and displaying them on a display unit; and sharing information by wirelessly communicating with other portable game machines. Note that Fig. 12C The portable game console shown is not limited thereto, and the portable game console can have various functions. Since the light-emitting element used for the display portion 7304 includes the compound of one embodiment of the present invention, high luminous efficiency can be achieved, so the portable game console including the display portion 7304 can reduce power consumption. Since the light-emitting element used for the display portion 7304 includes the compound of one embodiment of the present invention, each can be driven at a lower driving voltage, the portable game console can also reduce the driving voltage.

[0389] Fig.12DAn example of a mobile phone is shown. The mobile phone has a display portion 7402, an operation button 7403, an external connection port 7404, a speaker 7405, a microphone 7406, etc., which are assembled in a frame 7401. Note that the mobile phone includes a display portion 7402 having the same light-emitting elements as those shown in Embodiment Modes 3 and 4 and arranged in a matrix. Since each of the light-emitting elements includes a compound of an embodiment of the present invention, it can have high luminous efficiency and low driving voltage. Therefore, a mobile phone including a display portion 7402 formed using the light-emitting element can have low power consumption and low driving voltage.

[0390] when Fig.12D When the display portion 7402 of the mobile phone shown in the figure is touched with a finger or the like, data can be input to the mobile phone. In this case, operations such as making a call or writing an e-mail can be performed by touching the display portion 7402 with a finger or the like.

[0391] The display portion 7402 mainly has three screen modes. The first mode is a display mode mainly for image display. The second mode is an input mode mainly for inputting data such as text. The third mode is a display input mode that combines the display mode and the input mode.

[0392] For example, when making a phone call or writing an e-mail, the text displayed on the screen can be input in a text input mode in which the display portion 7402 is mainly used to input text. In this case, it is preferred that a keyboard or number buttons are displayed on most of the screen of the display portion 7402.

[0393] By providing a detection device having a sensor for detecting inclination such as a gyro sensor or an acceleration sensor inside the mobile phone, the orientation of the mobile phone (whether the mobile phone is placed vertically or horizontally) can be determined and the screen display of the display unit 7402 can be automatically switched.

[0394] The screen mode is switched by touching the display portion 7402 or operating the button 7403 on the frame body 7401. The screen mode may be switched according to the type of image displayed on the display portion 7402. For example, when the image signal displayed on the display portion is a signal of dynamic image data, the screen mode is switched to the display mode. When the signal is a signal of text data, the screen mode is switched to the input mode.

[0395] In addition, when it is found that there is no touch operation input to the display portion 7402 for a certain period of time by detecting a signal detected by the light sensor of the display portion 7402 in the input mode, the screen mode may be controlled to switch from the input mode to the display mode.

[0396] The display portion 7402 can also be used as an image sensor. For example, by touching the display portion 7402 with a palm or a finger, a palm print or a fingerprint can be photographed, thereby enabling personal identification. In addition, by using a backlight emitting near-infrared light or a sensing light source emitting near-infrared light in the display portion, finger veins, palm veins, etc. can also be photographed.

[0397] Note that the structure described in this embodiment can be combined with any of the structures described in Embodiments 1 to 4 as appropriate.

[0398] As described above, the light-emitting device including the light-emitting element of the compound of one embodiment of the present invention described in Embodiment 3 and Embodiment 4 has a very wide range of application, and the light-emitting device can be used in electronic devices in all fields. By using this compound, electronic devices with low power consumption and low driving voltage can be obtained.

[0399] A light-emitting element including the compound of one embodiment of the present invention can be used in a light source device. Fig.13 One embodiment is described. Note that the light source device includes a light-emitting element including a compound of one embodiment of the present invention as a means for irradiating light and includes at least an input / output terminal portion for supplying current to the light-emitting element. In addition, the light-emitting element is preferably isolated from the external atmosphere by a sealing means.

[0400] Fig.13 An example of a liquid crystal display device in which a light-emitting element including a compound according to one embodiment of the present invention is used as a backlight is shown. Fig.13 The liquid crystal display device shown includes a frame 901, a liquid crystal layer 902, a backlight 903, and a frame 904. The liquid crystal layer 902 is connected to a driver IC 905. The backlight 903 uses a light-emitting element containing the above compound, and current is supplied to the backlight 903 through a terminal 906.

[0401] By using the light-emitting element containing the above-mentioned compound in the backlight of the liquid crystal display device, a backlight with reduced power consumption can be obtained. In addition, by using the light-emitting element containing the above-mentioned compound, a surface-emitting lighting device can be manufactured, and a large-area surface-emitting lighting device can also be realized. Thus, the large-area backlight source and the large-area liquid crystal display device can be realized. Furthermore, the backlight source using the light-emitting element containing the above-mentioned compound can make the thickness of the light-emitting device smaller than the existing light-emitting device, so the thinning of the display device can also be realized.

[0402] Fig.14 An example in which a light-emitting element including a compound according to one embodiment of the present invention is used in a desk lamp as a lighting device is shown. Fig.14The desk lamp shown includes a housing 2001 and a light source 2002 , and the above-mentioned lighting device containing the compound is used as the light source 2002 .

[0403] Fig.15 An example of using a light-emitting element containing a compound of one embodiment of the present invention for an indoor lighting device 3001 is shown. The light-emitting element containing the above-mentioned compound is a light-emitting element with reduced power consumption, so that a lighting device with reduced power consumption can be realized. In addition, since the light-emitting element containing the above-mentioned compound can be realized in a large area, it can be used in a lighting device with a large area. In addition, since the thickness of the light-emitting element containing the above-mentioned compound is small, a lighting device that has been thinned can be manufactured. Fig.15 An example in which a light-emitting element including a compound according to one embodiment of the present invention is used in the display device 3002 is also shown.

[0404] The light-emitting element including the compound according to one embodiment of the present invention can also be mounted on a windshield or an instrument panel of a car. Fig.16 One embodiment of using a light-emitting element including the above compound for a windshield or a dashboard of a car is shown. Display regions 5000 to 5005 each include a light-emitting element including the above compound.

[0405] Display area 5000 and display area 5001 are display devices provided on the windshield of a car and equipped with a light-emitting element containing the above-mentioned compound. By using a light-transmitting electrode to form a first electrode and a second electrode, the light-emitting element containing the above-mentioned compound can be formed into a so-called perspective display device that can see the opposite side. When a perspective display is adopted, even if the perspective display device is provided on the windshield of a car, the field of view is not obstructed. Note that in the case of providing a transistor for driving, it is preferred to use a light-transmitting transistor, such as an organic transistor using an organic semiconductor material or a transistor using an oxide semiconductor.

[0406] Display area 5002 is a display device provided on a column portion and equipped with a light-emitting element including the above-mentioned compound. By displaying an image from an imaging unit provided on the vehicle body on display area 5002, the field of view blocked by the column can be supplemented. Similarly, display area 5003 provided on the instrument panel portion can compensate for the blind spot of the field of view blocked by the vehicle body by displaying an image from an imaging unit provided on the outside of the vehicle, thereby improving safety. By displaying an image to compensate for the invisible part of the driver, safety can be confirmed more naturally and simply.

[0407] Display area 5004 and display area 5005 can provide navigation data, speedometer, tachometer, driving distance, fueling amount, gear status, air conditioning settings and other various information. The user can change the display content and layout appropriately. Note that this information can also be displayed on display area 5000 to display area 5003. In addition, display area 5000 to display area 5005 can also be used as a lighting device.

[0408] The compound of one embodiment of the present invention can be used in electronic devices such as organic thin-film solar cells. Specifically, since the compound has carrier transport properties, it can be used in a carrier transport layer or a carrier injection layer. Since the compound can be photoexcited, it can be used in a power generation layer. [Example 1]

[0409] In this example, the synthesis method of N,N-bis[4-(6-phenylbenzo[b]naphtho[1,2-d]furan-8-yl)phenyl]-4-amino-p-terphenyl (abbreviated as: BnfBB1TP) (structural formula (103)), one of the organic compounds of one embodiment of the present invention, and the physical properties of the compound are described.

[0410] <Synthesis example 1> (Step 1: Synthesis of 4-(4-biphenylyl)triphenylamine) Into a 1000mL three-necked flask, 28g (85mmol) of 4-bromotriphenylamine, 17g (85mmol) of 4-biphenylboric acid, 0.92g (3.0mmol) of tri(o-tolyl)phosphine, 340mL of toluene, 85mL of ethanol and 100mL of potassium carbonate aqueous solution (2.0mol / L) were poured. The mixture was degassed under reduced pressure, and then nitrogen was continuously passed through the system. The mixture was heated to 60°C. Then 0.22g (1.0mmol) of palladium (II) anhydride was added, and the mixture was stirred at 80°C for 5.5 hours. After stirring, the mixture was cooled to room temperature, the precipitated solid was recovered by suction filtration, and washed with water, ethanol and toluene, thereby obtaining 29g of the target product as a light brown solid with a yield of 86%. The synthesis scheme of step 1 is shown in the following formula (A-1).

[0411]

[0412] (Step 2: Synthesis of N,N-bis(4-bromophenyl)-4-amino-p-terphenyl) 12 g (30 mmol) of 4-(4-biphenyl)triphenylamine and 1.5 L of ethyl acetate were added to a 2 L conical flask. The mixture was heated and stirred to fully dissolve the 4-(4-biphenyl)triphenylamine. After visually confirming the dissolution, 11 g (60 mmol) of N-bromosuccinimide (NBS) was added and the solution was stirred at room temperature for two days. The solution obtained after stirring was washed with water and saturated brine, and magnesium sulfate was added for drying. The mixture was gravity filtered, and 12 g of the target white solid was obtained with a yield of 73% by concentrating the filtrate. The synthesis scheme of step 2 is shown in the following formula (A-2).

[0413]

[0414] The obtained solid was subjected to nuclear magnetic resonance spectroscopy ( 1 H NMR), and the analysis results are shown below. 1 H NMR (chloroform-d, 500MHz): δ=7.0 (d, J=9.0Hz, 4H), 7.13 (d, J=8.5Hz, 2H), 7.37 (d, J =8.5Hz, 5H), 7.46 (t, J = 8.0Hz, 2H), 7.54 (d, J = 8.0Hz, 2H), 7.63-7.68 (m, 6H).

[0415] Fig.17A and Fig. 17B The obtained solid 1 H NMR spectrum. Note that Fig. 17B yes Fig.17A The enlarged view of the range from 6.5 ppm to 8.0 ppm. The measurement results showed that the target N,N-bis(4-bromophenyl)-4-amino-p-terphenyl was obtained.

[0416] (Step 3: Synthesis of N,N-bis[4-(6-phenylbenzo[b]naphtho[1,2-d]furan-8-yl)phenyl]-4-amino-p-terphenyl (abbreviation: BnfBB1TP)) 1.4 g (2.5 mmol) of N, N-bis (4-bromophenyl) -4-amino-p-terphenyl, 1.7 g (5.0 mmol) of 6-phenylbenzo [b] naphtho [1, 2-d] furan-8-boric acid, 0.11 g (0.40 mmol) of tri (o-tolyl) phosphine, 20 mL of toluene, 5 mL of ethanol and 5 mL of potassium carbonate aqueous solution (2.0 mol / L) were added to a 200 mL three-necked flask. The mixture was degassed under reduced pressure, and then nitrogen was continuously passed through the system. The mixture was heated to 60 ° C. Then, 50 mg (0.20 mmol) of palladium (II) anhydride was added and stirred at 80 ° C for 1.5 hours. After stirring, the precipitated solid was collected by suction filtration, washed with toluene, water and ethanol, and 1.0 g of brown powder was obtained with a yield of 41%. The synthesis scheme of step 3 is shown in the following formula (A-3).

[0417]

[0418] The obtained 1.0 g brown powder was purified by sublimation using a gradient sublimation method. The sublimation purification was carried out at a pressure of 3.2×10 -2 The brown powder was heated at 430°C for 15 hours under the conditions of 1.5% Pa. After sublimation purification, 0.65 g of the desired product as a pale yellow solid was obtained at a recovery rate of 63%.

[0419] The obtained solid was subjected to nuclear magnetic resonance spectroscopy ( 1 H NMR), and the analysis results are shown below. 1 H NMR (dichloromethane-d2, 500 MHz): δ = 7.34-7.39 (m, 7H), 7.41 (t, J = 7.5 Hz, 2H), 7.46 (t, J = 7.5 Hz, 2H), 7.53 (t, J = 7.5 Hz, 4H), 7.58-7.63 (m, 4H), 7.65-7.68 (m, 4H), 7.72-7.78 (m, 8H), 7.97 (d, J = 9.0 Hz, 4H), 8.06 (d, J = 7.5 Hz, 4H), 8.11 (t, J = 4.0 Hz, 4H), 8.43 (d, J = 8.0 Hz, 2H), 8.71 (d, J = 8.0 Hz, 2H).

[0420] Fig.18A and Fig.18B The obtained solid 1 H NMR spectrum. Note that Fig.18B yes Fig.18A The enlarged view of the range from 7.0 ppm to 9.0 ppm in FIG.

[0421] <Properties of BnfBB1TP> Fig.19 The absorption spectrum and emission spectrum of BnfBB1TP in toluene solution are shown. Fig. 20 The absorption spectrum and emission spectrum of the thin film of BnfBB1TP are shown. A solid thin film is formed on a quartz substrate by vacuum evaporation. The absorption spectrum of the toluene solution is measured using an ultraviolet-visible spectrophotometer (manufactured by JASCO Corporation, model V550). Fig.19 The absorption spectrum of BnfBB1TP in the toluene solution shown is obtained by the following method: subtracting the absorption spectrum of toluene measured by placing only toluene in a quartz cell from the absorption spectrum of BnfBB1TP in the toluene solution. In the measurement of the absorption spectrum of the thin film, a spectrophotometer (Spectrophotometer U4100 manufactured by Hitachi High-Technologies) is used. The emission spectrum is measured using a fluorescence spectrophotometer (FS920 manufactured by Hamamatsu Photonics K.K.).

[0422] From Fig.19 it can be seen that absorption peaks of BnfBB1TP in toluene solution are observed near 370 nm, 352 nm, and 324 nm, and the peak of the emission wavelength is at 416 nm (excitation wavelength 370 nm). From Fig. 20 it can be seen that absorption peaks of the thin film of BnfBB1TP are observed near 383 nm, 360 nm, 332 nm, and 266 nm, and the peak of the emission wavelength is near 446 nm (excitation wavelength 365 nm). It is confirmed that BnfBB1TP emits blue light. The compound of one embodiment of the present invention can be used as a host material for a luminescent substance or a host material for a fluorescent luminescent substance in the visible region.

[0423] The thin film of BnfBB1TP is not easily aggregated in the atmosphere, has little morphological change, and has good film quality.

[0424] The HOMO energy level and LUMO energy level of BnfBB1TP are measured and obtained by cyclic voltammetry (CV). The calculation method is as follows.

[0425] As a measuring device, an electrochemical analyzer (ALS model 600A or 600C manufactured by BAS Corporation) was used. The solution for CV measurement was prepared as follows: as a solvent, dehydrated dimethylformamide (DMF) (manufactured by Aldrich Co., Ltd., 99.8%, catalog number: 22705-6) was used, and tetra-n-butylammonium perchlorate (n-Bu4NClO4) (manufactured by Tokyo Chemical Industry Co., Ltd., catalog number: T0836) was dissolved at a concentration of 100 mmol / L as a supporting electrolyte. In addition, the measurement object was dissolved at a concentration of 2 mmol / L for preparation. A platinum electrode (manufactured by BAS Corporation, PTE platinum electrode) was used as a working electrode, a platinum electrode (manufactured by BAS Corporation, Pt counter electrode for VC-3 (5 cm)) was used as an auxiliary electrode, and Ag / Ag was used as a reference electrode. + Electrode (manufactured by BAS Corporation, RE7 non-aqueous solvent type reference electrode). Note that the measurement is carried out at room temperature (above 20°C and below 25°C). The scanning speed during CV measurement is unified to 0.1V / sec, and the oxidation potential Ea[V] and reduction potential Ec[V] relative to the reference electrode are measured. Note that Ea is the middle potential between oxidation-reduction waves, and Ec is the middle potential between reduction-oxidation waves. Here, it is known that the potential energy of the reference electrode used in this embodiment relative to the vacuum energy level is -4.94[eV], so the HOMO energy level [eV] = -4.94-Ea, LUMO energy level [eV] = -4.94-Ec are used to calculate the HOMO energy level and the LUMO energy level, respectively.

[0426] Furthermore, CV measurement was repeated 100 times, and the oxidation-reduction wave in the 100th measurement was compared with the oxidation-reduction wave in the first measurement to investigate the electrical stability of the compound.

[0427] The results show that in the measurement of the oxidation potential Ea [V] of BnfBB1TP, the HOMO energy level is -5.50 eV. On the other hand, the LUMO energy level is -2.52 eV. When the oxidation-reduction wave is repeatedly measured, in the Ea measurement, the peak intensity of the oxidation-reduction wave after the 100th cycle maintains 79% of the peak intensity of the oxidation-reduction wave in the first cycle, and in the Ec measurement, the peak intensity of the oxidation-reduction wave after the 100th cycle maintains 69% of the peak intensity of the oxidation-reduction wave in the first cycle. Therefore, it can be seen that BnfBB1TP has very high oxidation and reduction resistance.

[0428] In addition, differential scanning calorimetry (DSC measurement) of BnfBB1TP was performed using Pyris 1DSC manufactured by PerkinElmer, Inc. In the differential scanning calorimetry, the temperature was increased from -10°C to 320°C at a temperature increase rate of 40°C / min, and then the temperature was decreased from 320°C to -10°C at a temperature decrease rate of 50°C / min after being maintained at 320°C for 1 minute. This operation was performed twice in succession.

[0429] The DSC measurement results of the second cycle show that the glass transition temperature of BnfBB1TP is 163° C., the crystallization temperature is 215° C., and the melting point is 307° C., that is, BnfBB1TP has very high heat resistance.

[0430] In addition, thermogravimetric detection-differential thermal analysis (TG-DTA) of BnfBB1TP was performed. When measuring, a high vacuum differential thermogravimetric analyzer (TG-DTA2410SA manufactured by BrukerAXS KK) was used. The measurement was performed at a heating rate of 10°C / min under a nitrogen flow (flow rate of 200 mL / min) and atmospheric pressure. In thermogravimetric-differential thermal analysis, the temperature (decomposition temperature) at which the weight obtained by thermogravimetric measurement is reduced by 5% of the weight at the start of the measurement is above 500°C, indicating that BnfBB1TP has high heat resistance. [Example 2]

[0431] In this example, the synthesis method of 4,4'-bis(6-phenylbenzo[b]naphtho[1,2-d]furan-8-yl)-4"-phenyltriphenylamine (abbreviated as: BnfBB1BP) (structural formula (102)), one of the organic compounds of one embodiment of the present invention, and the physical properties of the compound are described.

[0432] <Synthesis example 2> (Step 1: Synthesis of 4,4'-bis(6-phenylbenzo[b]naphtho[1,2-d]furan-8-yl)-4"-phenyltriphenylamine (abbreviation: BnfBB1BP)) Into a 200 mL three-necked flask were poured 1.4 g (3.0 mmol) of 4,4'-dibromo-4"-phenyltriphenylamine, 2.0 g (6.0 mmol) of 6-phenylbenzo[b]naphtho[1,2-d]furan-8-boric acid, 0.31 g (1.0 mmol) of tri(o-tolyl)phosphine, 12 mL of toluene, 3 mL of ethanol and 5 mL of potassium carbonate aqueous solution (2.0 mol / L). The mixture was degassed under reduced pressure and then Nitrogen gas is continuously flowing through the system. The mixture is heated to 60°C. Then, 73 mg (0.32 mmol) of palladium (II) anhydride is added, and then stirred at 80°C for 6.5 hours. After stirring, the precipitated solid is collected by suction filtration, washed with toluene, water, and ethanol, and purified by high-speed liquid chromatography (mobile phase: chloroform) to obtain 1.1 g of the target product as a light yellow solid with a yield of 42%. The synthesis scheme is shown in the following formula (B-1).

[0433] 1.0 g of the obtained solid was sublimated and purified by gradient sublimation method. The solid was heated at 420° C. for 15 hours under a pressure of 3.6 Pa. After sublimation purification, 0.93 g of the target light yellow solid was obtained with a yield of 81%.

[0434]

[0435] The obtained solid was subjected to nuclear magnetic resonance spectroscopy ( 1 H NMR), and the analysis results are shown below. 1 H NMR (dichloromethane-d2, 500MHz): δ=7.33-7.38 (m, 7H), 7.41 (t, J=7.5Hz, 2H), 7.46 (t, J=7.5Hz, 2H), 7.52 (t, J=7.5Hz, 4H), 7.58-7.62 (m, 6H), 7.65 (d, J= 7.5Hz, 2H), 7.74-7.78 (m, 4H), 7.97 (d, J=9.0Hz, 4H), 8.05 (d, J=8.0Hz, 4H), 8.11 (t, J=4.0Hz, 4H), 8.43 (d, J=8.0Hz, 2H), 8.71 (d, J=8.0Hz, 2H).

[0436] Fig.21A and Fig. 21B The obtained solid 1 H NMR spectrum. Note that Fig. 21B yes Fig.21A The enlarged view of the range from 7.0 ppm to 9.0 ppm in FIG.

[0437] <Properties of BnfBB1BP> Next, Fig. 22 The absorption spectrum and emission spectrum of BnfBB1BP in toluene solution are shown. Fig.23 The absorption spectrum and emission spectrum of the thin film of BnfBB1BP are shown. The measurement method is the same as that of Example 1 shown above.

[0438] From Fig. 22 it can be seen that absorption peaks of BnfBB1BP in toluene solution are observed near 370 nm, 350 nm, and 324 nm, and the peak of the emission wavelength is at 404 nm (excitation wavelength 360 nm). From Fig.23 it can be seen that absorption peaks of the thin film of BnfBB1BP are observed near 382 nm, 355 nm, 330 nm, 278 nm, 257 nm, and 207 nm, and the peak of the emission wavelength is near 450 nm (excitation wavelength 370 nm). It is confirmed that BnfBB1BP emits blue light. The compound of one embodiment of the present invention can be used as a host material for a luminescent substance or a host material for a fluorescent luminescent substance in the visible region.

[0439] The thin film of BnfBB1BP is not easily aggregated under the atmosphere, has little morphological change, and has good film quality.

[0440] Next, the HOMO energy level and LUMO energy level of BnfBB1BP are obtained by cyclic voltammetry (CV) measurement. The calculation method is the same as that of Example 1.

[0441] In addition, CV measurement is repeated 100 times, and the oxidation-reduction wave in the 100th measurement is compared with the oxidation-reduction wave in the 1st measurement to investigate the electrical stability of the compound.

[0442] The results show that in the measurement of the oxidation potential Ea [V] of BnfBB1BP, the HOMO energy level is -5.51 eV. On the other hand, the LUMO energy level is -2.50 eV. When the oxidation-reduction wave is repeatedly measured, in the Ea measurement, the peak intensity of the oxidation-reduction wave after the 100th cycle maintains 79% of the peak intensity of the oxidation-reduction wave in the 1st cycle, and in the Ec measurement, the peak intensity of the oxidation-reduction wave after the 100th cycle maintains 77% of the peak intensity of the oxidation-reduction wave in the 1st cycle. Therefore, it can be known that the oxidation resistance and reducibility of BnfBB1BP are very high.

[0443] In addition, differential scanning calorimetry (DSC measurement) is performed on BnfBB1BP. The measurement method is the same as that of Example 1 shown above. From the DSC measurement results of the second cycle, it can be known that the glass transition temperature of BnfBB1BP is 155 °C, that is, BnfBB1BP has very high heat resistance.

[0444] In addition, thermogravimetric detection-differential thermal analysis (TG-DTA) of BnfBB1BP was performed. The measurement method was the same as that of Example 1 shown above. In the thermogravimetric-differential thermal analysis, the temperature (decomposition temperature) at which the weight obtained by thermogravimetric measurement decreased by 5% of the weight at the start of the measurement was 500°C or more, indicating that BnfBB1TP has high heat resistance. [Example 3]

[0445] In this example, a method for synthesizing N,N-bis[4-(dibenzofuran-4-yl)phenyl]-4-amino-p-terphenyl (abbreviated as DBfBB1TP), which is synthesized as a comparative substance of an organic compound according to one embodiment of the present invention, and the physical properties of the compound are described.

[0446] <Synthesis example 3> (Synthesis of N,N-bis[4-(dibenzofuran-4-yl)phenyl]-4-amino-p-terphenyl (abbreviation: DBfBB1TP) (structural formula (500))) Into a 200 mL three-necked flask, 2.8 g (5.0 mmol) of N, N-bis (4-bromophenyl) -4-amino-p-terphenyl, 2.1 g (10 mmol) of dibenzofuran-4-boric acid, 0.63 g (2.0 mmol) of tri (o-tolyl) phosphine, 20 mL of toluene, 5 mL of ethanol and 10 mL of potassium carbonate aqueous solution (2.0 mol / L) were poured. The mixture was degassed under reduced pressure, and then nitrogen was continuously flowed through the system. The mixture was heated to 60 ° C. Then, 97 mg (0.40 mmol) of palladium (II) anhydride was added, and then stirred at 80 ° C for 8.5 hours. After stirring, the precipitated solid was collected by suction filtration and washed with toluene, water, and ethanol. The organic layer of the filtrate was washed with water and saturated brine in turn, and magnesium sulfate was added to dry it. The mixture was gravity filtered and the filtrate was concentrated to obtain a solid. This solid was purified together with the solid recovered after the reaction by high performance liquid chromatography (mobile phase: chloroform) to obtain 1.8 g of the target product as a pale yellow solid with a yield of 48%. The synthesis scheme is shown in the following formula (C-1).

[0447]

[0448] The obtained solid of 1.8 g was purified by sublimation using a gradient sublimation method. The solid was heated at 436° C. for 15 hours under a pressure of 3.7 Pa. After the sublimation purification, 1.6 g of a light yellow solid was obtained with a yield of 91%.

[0449] The obtained solid was subjected to nuclear magnetic resonance spectroscopy ( 11H NMR), and the analysis results are shown below. 1 1H NMR (chloroform-d, 500 MHz): δ = 7.35 - 7.39 (m, 5H), 7.40 (d, J = 9.0 Hz, 4H), 7.44 (t, J = 7.5 Hz, 2H), 7.48 (q, J = 7.5 Hz, 4H), 7.64 (t, J = 7.5 Hz, 7H), 7.67 - 7.73 (m, 5H), 7.91 - 7.94 (m, 6H), 8.01 (d, J = 7.0 Hz, 2H).

[0450] <Properties of DBfBB1TP> The HOMO and LUMO energy levels of DBfBB1TP were measured by cyclic voltammetry (CV). The calculation method is the same as that in Example 1.

[0451] In the measurement of the oxidation potential Ea [V] of DBfBB1TP, the HOMO energy level was -5.49 eV, and the LUMO energy level was -2.31 eV. The LUMO energy levels of BnfBB1TP and BnfBB1BP are both about -2.5 eV. It can be seen that a substance with a lower LUMO energy level than the dibenzofuran (DBf) skeleton can be obtained by having a benzo[b]naphtho[1,2-d]furan skeleton.

[0452] DSC measurement and TG-DTA measurement were carried out on DBfBB1TP in the same manner as in Example 1. From the measurement results, the glass transition temperature was 124 °C, the melting point was 258 °C, and the decomposition temperature was 483 °C. From this result, Example 1 and Example 2, it can be seen that compared with DBfBB1TP having a dibenzofuran skeleton, BnfBB1TP and BnfBB1BP having a benzo[b]naphtho[1,2-d]furan skeleton of the present invention have higher heat resistance. In addition, it can be seen that the compounds of the present invention have a high recovery rate, high heat resistance and high sublimability in sublimation purification. [Example 4]

[0453] In this example, an example of manufacturing a light-emitting element containing an organic compound of an embodiment of the present invention and the characteristics of the light-emitting element will be described. The cross-sectional view of the light-emitting element manufactured in this example is the same as Figure 1B the same. Table 1 shows the detailed element structure. In addition, the structures and abbreviations of the compounds used here are shown below. Note that for other compounds, reference can be made to the descriptions in the above examples.

[0454]

[0455] [Table 1]

[0456] <Manufacturing of Light Emitting Element> 《Manufacturing of Light Emitting Element 1》 A 70 nm thick ITSO film was formed on a glass substrate by sputtering as an electrode 101. The electrode area of ​​the electrode 101 was 4 mm 2 (2 mm × 2 mm). Next, as a pretreatment for forming a light-emitting element on the substrate, the substrate surface was washed with water, dried at 200°C for 1 hour, and subjected to UV ozone treatment for 370 seconds. -4 The substrate was baked at 170° C. for 30 minutes in a vacuum evaporation apparatus with a vacuum degree of about Pa. Then, the substrate was cooled for about 30 minutes.

[0457] Next, 2,3,6,7,10,11-hexacyano-1,4,5,8,9,12-hexaazatriphenylene (abbreviation: HAT-CN) was deposited on the electrode 101 to a thickness of 5 nm as the hole injection layer 111 .

[0458] Next, 4,4′-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB) was deposited on the hole injection layer 111 to a thickness of 10 nm as the first hole transport layer 112 - a .

[0459] Next, a 10 nm thick organic compound N,N-bis[4-(6-phenylbenzo[b]naphtho[1,2-d]furan-8-yl)phenyl]-4-amino-p-terphenyl (abbreviated as: BnfBB1TP) which is an embodiment of the present invention is vapor deposited on the first hole transport layer 112-a as the second hole transport layer 112-b.

[0460] Next, 3,6-bis[4-(2-naphthyl)phenyl]-9-phenyl-9H-carbazole (abbreviated as βNP2PC) was vapor-deposited to a thickness of 10 nm on the second hole transport layer 112 - b as the third hole transport layer 112 - c .

[0461] Next, as the light-emitting layer 113, 7-[4-(10-phenyl-9-anthracenyl)phenyl]-7H-dibenzo[c,g]carbazole (abbreviated as: cgDBCzPA) and N,N'-bis(3-methylphenyl)-N,N'-bis[3-(9-phenyl-9H-fluorene-9-yl)phenyl]pyrene-1,6-diamine (abbreviated as: 1,6mMemFLPAPrn) were co-evaporated on the third hole transport layer 112-c, and the weight ratio of cgDBCzPA to 1,6mMemFLPAPrn was 1:0.03 and the thickness was 25nm. In the light-emitting layer 113, cgDBCzPA is the main material and 1,6mMemFLPAPrn is the light-emitting material.

[0462] Next, cgDBCzPA was deposited to a thickness of 10 nm as the first electron transport layer 114 - b on the light emitting layer 113. Then, bathophenanthroline (abbreviated as BPhen) was deposited to a thickness of 15 nm as the second electron transport layer 114 - a on the first electron transport layer 114 - b.

[0463] Next, as the electron injection layer 115 , lithium fluoride (LiF) was deposited on the second electron transport layer 114 - a to a thickness of 1 nm.

[0464] As the electrode 102 , aluminum (Al) was deposited on the electron injection layer 115 to a thickness of 200 nm.

[0465] Next, in a glove box with a nitrogen atmosphere, the glass substrate on which the light-emitting element 1 is formed is fixed to the substrate (counter substrate) using an organic EL sealant to seal the light-emitting element 1. Specifically, a desiccant is attached to the counter substrate, and then the counter glass substrate on which the sealant is applied around the formation range of the opposite light-emitting element and the substrate on which the light-emitting element is formed are attached. Then, the light-emitting element 1 is sealed with 6 J / cm 2 The ultraviolet light having a wavelength of 365 nm was irradiated, and a heat treatment was performed at 80° C. for 1 hour. The light-emitting element 1 was obtained through the above steps.

[0466] 《Manufacturing of Light Emitting Element 2》 The light-emitting element 2 is different from the light-emitting element 1 only in the process of forming the second hole transport layer 112 - b , and the other processes are the same as the manufacturing method of the light-emitting element 1 .

[0467] As the second hole transport layer 112 - b of the light-emitting element 2 , BnfBB1BP was evaporated to a thickness of 10 nm.

[0468] 《Manufacturing of Comparative Light Emitting Element 3》 The only difference between the light-emitting element 3 and the light-emitting element 1 is the step of forming the second hole transport layer 112 - b , and the other steps are the same as the manufacturing method of the light-emitting element 1 .

[0469] As the second hole transport layer 112 - b of the comparative light-emitting element 3, DBfBB1TP was evaporated to a thickness of 10 nm.

[0470] <Characteristics of Light Emitting Element> Next, the characteristics of the light-emitting element 1, light-emitting element 2, and comparative light-emitting element 3 manufactured as described above were measured. The brightness and CIE chromaticity were measured using a colorimeter (BM-5A manufactured by Topcon Technohouse). The electroemission spectrum was measured using a multi-channel spectrum analyzer (PMA-11 manufactured by Hamamatsu Photonics Co., Ltd., Japan).

[0471] Fig.24The current efficiency-luminance characteristics of Light-Emitting Element 1, Light-Emitting Element 2, and Comparative Light-Emitting Element 3 are shown. Fig.25 Brightness-voltage characteristics are shown. Fig.26 The external quantum efficiency-luminance characteristics are shown. The measurement of each light-emitting element was performed at room temperature (atmosphere maintained at 23° C.).

[0472] Table 2 shows the 2 Element characteristics of nearby light-emitting element 1, light-emitting element 2, and comparison light-emitting element 3.

[0473] [Table 2]

[0474] Fig. 27 Shown at 12.5 mA / cm 2 Electroemission spectra when current of a current density of 200 Å is passed through light-emitting element 1, light-emitting element 2, and comparison light-emitting element 3.

[0475] like Fig.24 , Fig.26 As shown in Table 2, Light Emitting Element 1, Light Emitting Element 2, and Comparative Light Emitting Element 3 each have high current efficiency and external quantum efficiency. The maximum values ​​of the external quantum efficiency of Light Emitting Element 1, Light Emitting Element 2, and Comparative Light Emitting Element 3 are all above 11%, which are extremely good values ​​for fluorescent elements.

[0476] The probability of generating a singlet exciton generated by the recombination of carriers (holes and electrons) injected from a pair of electrodes is 25%, so when the light extraction efficiency to the outside is 25%, the theoretical value of the external quantum efficiency of the fluorescent element is 6.25% at most. The external quantum efficiencies of light-emitting element 1, light-emitting element 2, and comparative light-emitting element 3 are each above 11%, that is, they all exceed the theoretical limit. The reason for this is considered to be as follows: in light-emitting element 1, light-emitting element 2, and comparative light-emitting element 3, in addition to the light emission from the singlet exciton generated by the recombination of carriers injected from a pair of electrodes, the triplet excitons partially converted into singlet excitons due to the TTA shown in embodiment 3 contribute to the fluorescence emission. Although not illustrated in this example, delayed fluorescence was observed from light-emitting element 1, light-emitting element 2, and comparative light-emitting element 3 by transient fluorescence measurement. It can be seen from this that light-emitting element 1, light-emitting element 2, and comparative light-emitting element 3 obtained external quantum efficiencies above the theoretical limit due to TTA.

[0477] As shown in Table 2, the light emitting element 1, the light emitting element 2, and the comparative light emitting element 3 have a brightness of 1000 cd / m 2 The driving voltage in the vicinity is 3.5 V or less, and has high power efficiency.

[0478] Depend on Fig. 27It can be seen that the electroemission spectra of Light-emitting Element 1, Light-emitting Element 2 and Comparative Light-emitting Element 3 have spectral peaks near 465nm, and the full width at half maximum is about 40nm. Light-emitting Element 1, Light-emitting Element 2 and Comparative Light-emitting Element 3 exhibit good blue light emission.

[0479] <Reliability of Light Emitting Components> Next, a driving test was performed on the light-emitting element 1, the light-emitting element 2, and the comparative light-emitting element 3 at a constant current of 2 mA. Fig.28 The results are shown in Figure 2. Fig.28 It can be seen that the LT of light emitting element 1, light emitting element 2, and comparative light emitting element 3 70 (30% brightness reduction time) is more than 250 hours and has high reliability. Fig.28 It can be seen that the Light-emitting Element 1 and the Light-emitting Element 2 have higher reliability than the Comparative Light-emitting Element 3. This shows that the benzo[b]naphtho[1,2-d]furan skeleton can obtain higher reliability than the dibenzofuran skeleton. [Example 5]

[0480] In this example, the synthesis method of N,N-bis[4-(benzo[b]naphtho[1,2-d]furan-6-yl)phenyl]-4-amino-p-terphenyl (abbreviated as: Bnf(6)BB1TP) (structural formula (106)), which is one of the organic compounds of one embodiment of the present invention, and the physical properties of the compound are described.

[0481] <Synthesis example 4> (Step 1: Synthesis of N,N-bis[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-4-amino-p-terphenyl) 1.7 g (3.0 mmol) of N, N-bis (4-bromophenyl) -4-amino-p-terphenyl, 1.4 g (3.0 mmol) of bis (valeryl) diboron, 0.10 g (0.20 mmol) of 2-di-tert-butylphosphino-2', 4', 6' triisopropylbiphenyl (abbreviated as: tBuXphos) and 1.3 g (12 mmol) of potassium acetate were added to a 200 mL three-necked flask. Then, the air in the system was replaced with nitrogen. 30 mL of xylene was added to the mixture, and then the mixture was degassed under reduced pressure, and then nitrogen was continuously passed through the system. After heating the mixture to 60°C, 88 mg (0.10 mmol) of [1,1'-bis (diphenylphosphino) ferrocene] dichloropalladium (II) was added, and then stirred at 120°C for 7.5 hours. After confirming the disappearance of the raw materials by thin layer chromatography, the next step of the reaction was carried out. The synthesis scheme of step 1 is shown in the following formula (D-1).

[0482]

[0483] (Step 2: Synthesis of Bnf(6)BB1TP) To the mixture obtained in step 1, 2.1 g (6.0 mmol) of 6-iodobenzo[b]naphtho[1,2-d]furan, 85 mg (0.20 mmol) of tBuXphos, and 4.1 g (12 mmol) of cesium carbonate were added. The mixture was degassed under reduced pressure, and then nitrogen was continuously passed through the system. After the mixture was heated to 60°C, 86 mg (0.10 mmol) of [1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium(II) was added, and then stirred at 120°C for 15 hours. After stirring, the obtained mixture was washed with water and saturated brine and dried with magnesium sulfate. The obtained mixture was gravity filtered and the filtrate was concentrated to obtain a solid. The obtained solid was purified by high-speed liquid chromatography (HPLC) to obtain 1.0 g of the target object as a light yellow solid with a yield of 60%. The synthesis scheme of step 2 is shown in the following formula (D-2).

[0484]

[0485] The obtained 0.89 g solid was sublimated and purified by gradient sublimation method. In the sublimation purification, argon was introduced at a flow rate of 15 mL / min and the solid was heated at 410° C. for 15 hours under a pressure of 3.1 Pa. After sublimation purification, 0.59 g of the target light brown solid was obtained with a yield of 67%.

[0486] The obtained solid was subjected to nuclear magnetic resonance spectroscopy ( 1 H NMR), and the analysis results are shown below. 1 H NMR (chloroform-d, 500 MHz): δ = 7.35-7.60 (m, 14H), 7.65-7.77 (m, 12H), 7.84 (d, J = 8.5 Hz, 1H), 7.95-8.09 (m, 8H), 8.39 (d, J = 8.5 Hz, 1H), 8.46-8.50 (m, 1H), 8.68 (t, J = 8.5 Hz, 2H).

[0487] Fig.29A and Fig.29B The obtained solid 1 H NMR spectrum. Note that Fig.29B yes Fig.29A The enlarged view of the range from 7.0 ppm to 9.0 ppm in FIG.

[0488] The MS spectrum of the obtained solid was measured using laser desorption ionization method (LDI-TOFMS). The LDI-TOFMS measurement was carried out using an ultra-high resolution MALDI-TOFMS system manufactured by JEOL Ltd. This measurement was performed by dropping a chloroform solution of Bnf(6)BB1TP at any concentration onto the target plate in the cationic spiral mode. As a result of setting the laser power to 40 and accumulating more than 200 times, m / z 829.3 was confirmed, from which it can be known that Bnf(6)BB1TP (the target substance) was obtained.

[0489] <Properties of Bnf(6)BB1TP> Next, Fig.30 The absorption spectrum and emission spectrum of Bnf(6)BB1TP in toluene solution are shown. Fig.31 The absorption spectrum and emission spectrum of the thin film of Bnf(6)BB1TP are shown. The measurement method is the same as that in Example 1 above.

[0490] It can be seen from Fig.30 that Bnf(6)BB1TP in toluene solution observes an absorption peak near 367 nm, and the peak of the emission wavelength is at 424 nm (excitation wavelength 366 nm). It can be seen from Fig.31 that the thin film of Bnf(6)BB1TP observes absorption peaks near 374 nm, 350 nm, and 256 nm, and the peak of the emission wavelength is near 451 nm (excitation wavelength 380 nm). It was confirmed that Bnf(6)BB1TP emits blue light. The compound of one embodiment of the present invention can be used as a luminescent substance or a host material for a fluorescent luminescent substance in the visible region.

[0491] The thin film of Bnf(6)BB1TP is not easily aggregated in the atmosphere, has little morphological change, and has good film quality.

[0492] Next, the HOMO energy level and LUMO energy level of Bnf(6)BB1TP were obtained by cyclic voltammetry (CV) measurement. The calculation method is the same as that in Example 1.

[0493] In addition, CV measurement was repeated 100 times, and the oxidation-reduction wave in the 100th measurement was compared with the oxidation-reduction wave in the 1st measurement to investigate the electrical stability of the compound.

[0494] The results show that in the measurement of the oxidation potential Ea [V] of Bnf (6) BB1TP, the HOMO energy level is -5.50 eV. On the other hand, the LUMO energy level is -2.51 eV. When the oxidation-reduction wave is repeatedly measured, in the Ea measurement, the peak intensity of the oxidation-reduction wave after the 100th cycle maintains 88% of the peak intensity of the oxidation-reduction wave in the first cycle, and in the Ec measurement, the peak intensity of the oxidation-reduction wave after the 100th cycle maintains 99% of the peak intensity of the oxidation-reduction wave in the first cycle. Therefore, it can be seen that Bnf (6) BB1TP has very high oxidation and reduction resistance.

[0495] In addition, differential scanning calorimetry (DSC) was performed on Bnf(6)BB1TP. The measurement method was the same as that of Example 1 described above. From the DSC measurement results of the second cycle, it was found that the glass transition temperature of Bnf(6)BB1TP was 163°C, that is, it had very high heat resistance.

[0496] In addition, thermogravimetric detection-differential thermal analysis (TG-DTA) of Bnf(6)BB1TP was performed. The measurement method was the same as in Example 1. In the thermogravimetric-differential thermal analysis, the temperature (decomposition temperature) at which the weight obtained by thermogravimetric measurement decreased by 5% of the weight at the start of the measurement was 500°C or higher, indicating that Bnf(6)BB1TP had high heat resistance. [Example 6]

[0497] In this example, the synthesis method of N,N-bis[4-(benzo[b]naphtho[1,2-d]furan-8-yl)phenyl]-4-amino-p-terphenyl (abbreviated as: Bnf(8)BB1TP) (structural formula (117)), one of the organic compounds of one embodiment of the present invention, and the physical properties of the compound are described.

[0498] <Synthesis example 5> (Step 1: Synthesis of N,N-bis[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)phenyl]-4-amino-p-terphenyl) Into a 200 mL three-necked flask, 0.56 g (1.0 mmol) of N, N-bis (4-bromophenyl) -4-amino-p-terphenyl, 0.52 g (2.0 mmol) of bis (valeryl) diboron, 0.85 g (0.20 mmol) of 2-di-tert-butylphosphino-2', 4', 6' triisopropylbiphenyl (abbreviated as: tBuXphos) and 0.39 g (4.0 mmol) of potassium acetate were poured. Then, the air in the system was replaced with nitrogen. 10 mL of xylene was added to the mixture, and then the mixture was degassed under reduced pressure, and then nitrogen was continuously passed through the system. After the mixture was heated to 60°C, 87 mg (0.10 mmol) of [1,1'-bis (diphenylphosphino) ferrocene] dichloropalladium (II) was added, and then stirred at 120°C for 6 hours. After confirming the disappearance of the raw materials by thin layer chromatography, the next step of the reaction was carried out. The synthesis scheme of step 1 is shown in the following formula (E-1).

[0499]

[0500] (Step 2: Synthesis of Bnf(8)BB1TP) To the mixture obtained in step 1, 0.51 g (2.0 mmol) of 8-chlorobenzo[b]naphtho[1,2-d]furan, 83 mg (0.20 mmol) of tBuXphos and 1.4 g (4.0 mmol) of cesium carbonate were added. The mixture was degassed under reduced pressure, and then nitrogen was continuously passed through the system. After the mixture was heated to 60°C, 82 mg (0.10 mmol) of [1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium(II) was added, and then stirred at 120°C for 15 hours. After stirring, the obtained mixture was filtered using diatomaceous earth (Wako Pure Chemical Industries, Ltd., catalog number: 537-02305), magnesium silicate (Wako Pure Chemical Industries, Ltd., catalog number: 066-05265) and alumina. The obtained filtrate was concentrated to obtain the target object as a light yellow solid. The synthesis scheme of step 2 is shown in the following formula (E-2).

[0501]

[0502] The MS spectrum of the obtained solid was measured by LDI-TOFMS. The measurement method was the same as in Example 5. m / z 829.3 was observed by the above measurement, which showed that Bnf(8)BB1TP (the target compound) was obtained. [Example 7]

[0503] In this example, a light-emitting element using Bnf(6)BB1TP, an organic compound according to one embodiment of the present invention, as the hole transport layer 112-b is described. The light-emitting element manufactured in this example is the same as that in Example 4, so the description of its manufacturing method is omitted. The cross-sectional view of the structure of the light-emitting element manufactured in this example is similar to that of Example 4. Figure 1B The detailed element structure is shown in Table 3. In addition, the structures and abbreviations of the compounds used are shown below. Note that for other compounds, reference can be made to the description of the above examples.

[0504]

[0505] [Table 3]

[0506] <Hole Transport Layer 112-c of Light Emitting Element> On the hole transport layer 112 - b of the light emitting element 4 and the comparative light emitting element 5, 3,3′-(naphthalene-1,4-diyl)bis(9-phenyl-9H-carbazole) (abbreviated as PCzN2) was vapor-deposited to a thickness of 10 nm as the hole transport layer 112 - c.

[0507] <Characteristics of Light Emitting Element> Next, the characteristics of the light-emitting element 4 and the comparative light-emitting element 5 manufactured as described above were measured. The measurement was performed in the same manner as in Example 4.

[0508] Fig.32 The current efficiency-luminance characteristics of the light-emitting element 4 and the comparative light-emitting element 5 are shown. Fig.33 The current density-voltage characteristics are shown. Fig.34 The external quantum efficiency-luminance characteristics are shown.

[0509] Table 4 shows 1000 cd / m 2 Element characteristics of the nearby light-emitting element 4 and the comparative light-emitting element 5.

[0510] [Table 4]

[0511] Fig.35 Shown at 12.5 mA / cm 2 Electroemission spectra when a current of a current density of 200 Å is passed through light-emitting element 4 and comparison light-emitting element 5.

[0512] like Fig.32 , Fig.34As shown in Table 4, Light-emitting Element 4 and Comparative Light-emitting Element 5 each have high current efficiency and external quantum efficiency. The maximum values ​​of the external quantum efficiency of Light-emitting Element 4 and Comparative Light-emitting Element 5 are both above 11%, which are extremely good values ​​as fluorescent elements. As with the light-emitting element described in Example 4, Light-emitting Element 4 and Comparative Light-emitting Element 5 obtain external quantum efficiencies above the theoretical limit due to TTA.

[0513] As shown in Table 4, the light emitting element 4 and the comparative light emitting element 5 have a brightness of 1000 cd / m 2 The driving voltage in the vicinity is all below 3.2 V and has good power efficiency.

[0514] Depend on Fig.35 It can be seen that the emission spectrum of each of Light-emitting Element 4 and Comparative Light-emitting Element 5 has a spectral peak near 465 nm and a full width at half maximum of about 35 nm, so Light-emitting Element 4 and Comparative Light-emitting Element 5 exhibit good blue light emission.

[0515] <Reliability of Light Emitting Components> Next, a driving test was performed on the light-emitting element 4 and the comparative light-emitting element 5 at a constant current of 2 mA. Fig.36 The results are shown in Figure 2. Fig.36 It can be seen that the LT of the light emitting element 4 90 (Brightness 10% reduction time) exceeds 100 hours and has good reliability. Fig.36 It can be seen that the light-emitting element 4 has higher reliability than the comparative light-emitting element 5. This shows that the benzo[b]naphtho[1,2-d]furan skeleton can obtain higher reliability than the dibenzofuran skeleton. Explanation of symbols

[0516] 50: Adhesive layer, 51: Adhesive layer, 52: Adhesive layer, 100: Light-emitting element, 101: Electrode, 102: Electrode, 103: EL layer, 110: Light-emitting element, 111: Hole injection layer, 112: Hole transport layer, 112-a: Hole transport layer, 112-b: Hole transport layer, 112-c: Hole transport layer, 113: Light-emitting layer, 114: Electron transport layer, 114-a: Electron transport layer, 114-b: Electron transport layer, 115: Electron injection layer, 120: Light-emitting element, 121: Host material, 122: Guest material, 131: Hole injection material, 132: Hole transport material, 133: Hole transport material, 134: Hole transport material, 135: Host material, 1 36: guest material, 150: light-emitting element, 201: resin layer, 202: resin layer, 300: display device, 311: electrode, 311b: electrode, 340: liquid crystal element, 351: substrate, 360: light-emitting element, 360b: light-emitting element, 360g: light-emitting element, 360r: light-emitting element, 360w: light-emitting element, 361: substrate, 362: display part, 364: circuit part, 365: wiring, 366: circuit part, 367: wiring, 372: FPC, 373: IC, 374: FPC, 375: IC, 400: display device, 401: transistor, 402: transistor, 403: transistor, 405: capacitor, 406: connection part, 410: Pixel, 411: insulating layer, 412: insulating layer, 413: insulating layer, 414: insulating layer, 415: insulating layer, 416: spacer, 417: adhesive layer, 419: connecting layer, 421: electrode, 422: EL layer, 423: electrode, 424: optical adjustment layer, 425: coloring layer, 426: light shielding layer, 451: opening, 476: insulating layer, 478: insulating layer, 501: transistor, 502: electrode, 503: transistor, 505: capacitor, 506: connecting portion, 510: electrode, 511: insulating layer, 512: insulating layer, 513: insulating layer, 514: insulating layer, 517: adhesive layer, 519: connecting layer, 521: light emitting unit, 522: light emitting unit, 523: Charge generation layer, 529: Liquid crystal element, 543: Connector, 562: Electrode, 563: Liquid crystal, 564a: Orientation film, 564b: Orientation film, 576: Insulation layer, 578: Insulation layer, 599: Polarizer, 601: Source side driving circuit, 602: Pixel portion, 603: Gate side driving circuit, 604: Sealing substrate, 605: Sealing agent, 607: Space, 608: Wiring, 610: Element substrate, 611: Switching TFT, 612: Current control TFT, 613: Electrode, 614: Insulator, 616: EL layer, 617: Electrode, 618: Light emitting element, 623: n-channel TFT, 624: p-channel TFT, 700: Display panel,701: resin layer, 702: resin layer, 800: display panel, 901: frame, 902: liquid crystal layer, 903: backlight, 904: frame, 905: driver IC, 906: terminal, 1001: substrate, 1002: base insulating film, 1003: gate insulating film, 1006: gate electrode, 1007: gate electrode, 1008: gate electrode, 1020: interlayer insulating film, 1021: interlayer insulating film, 1022: electrode, 1025B: lower electrode, 1024B: electrode, 1025G: Lower electrode, 1024G: electrode, 1025R: lower electrode, 1024R: electrode, 1026: partition wall, 1028: EL layer, 1029: electrode, 1031: sealing substrate, 1032: sealant, 1033: base material, 1034B: coloring layer, 1034G: coloring layer, 1034R: coloring layer, 1035: black layer (black matrix), 1036: cover layer, 1037: interlayer insulating film, 1040: pixel portion, 1041: driving circuit portion, 1042: peripheral portion, 2001: Frame, 2002: Light source, 3001: Illuminating device, 3002: Display device, 5000: Display area, 5001: Display area, 5002: Display area, 5003: Display area, 5004: Display area, 5005: Display area, 7101: Frame, 7103: Display unit, 7105: Bracket, 7107: Display unit, 7109: Operation key, 7110: Remote control unit, 7201: Main body, 7202: Frame, 7203: Display unit, 7204: Keyboard, 7205: External Connection port, 7206: pointing device, 7301: housing, 7302: housing, 7303: connection part, 7304: display part, 7305: display part, 7306: speaker part, 7307: recording medium insertion part, 7308: LED light, 7309: operation key, 7310: connection terminal, 7311: sensor, 7312: microphone, 7401: housing, 7402: display part, 7403: operation button, 7404: external connection port, 7405: speaker, 7406: microphone. This application is based on Japanese Patent Application No. 2016-179489 filed with the Japan Patent Office on September 14, 2016, the entire contents of which are incorporated herein by reference.

Claims

1. An organic compound represented by the general formula (G0): in, Ar 1 ,Ar 2 and Ar 3 each independently represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms, Ar 4 represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms, n, m and l each independently represent an integer of 0 or 1, A 1 represents the general formula (g0) or the general formula (g1), A 2 represents the general formula (g0) or the general formula (g1), Ar 5 and Ar 6 each independently represents a substituted or unsubstituted aromatic hydrocarbon group having 6 to 13 carbon atoms, And, R 1 To R 18 Each independently represents any one of hydrogen, a hydrocarbon group having 1 to 6 carbon atoms, a cycloalkyl group having 3 to 6 carbon atoms, an alkoxy group having 1 to 6 carbon atoms, a cyano group, a halogen, a haloalkyl group having 1 to 6 carbon atoms, and a substituted or unsubstituted aromatic hydrocarbon group having 6 to 25 carbon atoms.

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