Organic compound, light-emitting element, and method for synthesizing organic compound

Abstract

One embodiment of the present invention provides an organic compound, a light-emitting element, and a method for synthesizing the organic compound. The method for synthesizing the organic compound includes reacting an organic material with an amine compound and purifying the organic compound by sublimation. The reaction is performed using a palladium compound.

Description

[0001] This application is a divisional application of the Chinese patent application with national application number 201711129252.4 and titled “Light-emitting element, display device, electronic device and lighting device”. Technical Field

[0002] One embodiment of the present invention relates to a light-emitting element using a combination of organic compounds that form an exciplex, or a display device, an electronic device, and a lighting device including the light-emitting element.

[0003] Note that one embodiment of the present invention is not limited to the aforementioned technical fields. One embodiment of the present invention relates to an object, method, or manufacturing method. Alternatively, the present invention relates to a process, machine, product, or composition of matter. 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, and methods for manufacturing the same. Background Art

[0004] In recent years, research and development of light-emitting devices utilizing electroluminescence (EL) have become increasingly intense. The basic structure of these light-emitting devices consists of a layer containing a light-emitting material (EL layer) sandwiched between a pair of electrodes. Light is emitted from the light-emitting material by applying a voltage between the electrodes.

[0005] Since the light-emitting element is a self-luminous element, a display device using the light-emitting element has advantages such as good visibility, no need for a backlight, and low power consumption. It also has the following advantages: it can be made thin and light; and it has a fast response speed.

[0006] When a light-emitting element (e.g., an organic EL element) is used that uses an organic material as a light-emitting material and has an EL layer containing the light-emitting material disposed between a pair of electrodes, voltage is applied between the pair of electrodes, causing electrons and holes (holes) to be injected from the cathode and anode, respectively, into the light-emitting EL layer, thereby causing current to flow. The injected electrons then recombine with the holes, causing the light-emitting organic material to enter an excited state, thereby allowing light to be emitted from the excited light-emitting organic material.

[0007] As the types of excited states formed in organic materials, there are singlet excited states (S * ) and triplet excited state (T * ), the emission from the singlet excited state is called fluorescence, and the emission from the triplet excited state is called phosphorescence. In addition, in this light-emitting element, the statistical generation ratio of the singlet excited state to the triplet excited state is S * :T* =1:3. Therefore, light-emitting elements using materials that emit phosphorescence (phosphorescent materials) have higher luminous efficiency than light-emitting elements using materials that emit fluorescence (fluorescent materials). Consequently, in recent years, light-emitting elements using phosphorescent materials that can convert triplet excited states into luminescent light have been actively developed (for example, see Patent Document 1).

[0008] The energy required to excite an organic material depends on the energy difference between the highest occupied molecular orbital (Highest Occupied Molecular Orbital, also known as HOMO) energy level and the lowest unoccupied molecular orbital (Lowest Unoccupied Molecular Orbital, also known as LUMO) energy level of the organic material, and the energy difference is roughly equivalent to the energy of the singlet excited state. In a light-emitting element using an organic material that emits phosphorescence, triplet excitation energy can be converted into luminescent energy. Thus, when the energy difference between the singlet excited state and the triplet excited state formed by the organic material is large, the energy required for the organic material to be excited is higher than the luminescent energy, and the higher energy is equivalent to the energy difference. The difference between the energy required for the organic material to be excited and the luminescent energy causes the driving voltage of the light-emitting element to rise and affects the device characteristics, so it is necessary to suppress the method for raising the driving voltage.

[0009] [Patent Document 1] Japanese Patent Application Publication No. 2010-182699

[0010] To reduce the driving voltage, it is necessary to use organic materials with good carrier (electron and / or hole) transport properties in light-emitting elements. However, when using such organic materials, it is sometimes difficult to balance the carriers and make the light-emitting elements emit light efficiently, making it difficult to achieve both good luminous efficiency and low driving voltage at the same time. Summary of the Invention

[0011] In view of the above problems, one object of one embodiment of the present invention is to provide a novel light-emitting element comprising a phosphorescent material, particularly a light-emitting element with high luminous efficiency. Another object of one embodiment of the present invention is to provide a light-emitting element with reduced voltage. Another object of one embodiment of the present invention is to provide a light-emitting element with high reliability.

[0012] Another object of the present invention is to provide a low-power light-emitting element. Another object of one embodiment of the present invention is to provide a novel light-emitting device. Another object of one embodiment of the present invention is to provide a novel display device.

[0013] In addition, the description of the above-mentioned subject does not prevent the existence of other subjects. Note that one embodiment of the present invention does not necessarily achieve all of the above-mentioned purposes. In addition, subjects other than the above-mentioned subject can be known and derived from the description of the specification, etc.

[0014] One embodiment of the present invention is a light-emitting element capable of forming an exciplex capable of efficiently exciting a phosphorescent material.

[0015] Therefore, a light-emitting element of one embodiment of the present invention includes a light-emitting layer between a pair of electrodes, the light-emitting layer containing a first organic compound, a second organic compound and a guest material, the LUMO energy level of the first organic compound is lower than the LUMO energy level of the second organic compound, the difference between the LUMO energy level of the first organic compound and the LUMO energy level of the second organic compound is greater than 0 eV and is less than 0.5 eV, the HOMO energy level of the first organic compound is lower than the HOMO energy level of the second organic compound, the guest material can convert triplet excitation energy into light emission, and the first organic compound and the second organic compound form an exciplex.

[0016] In the above structure, the first organic compound preferably has a first electron-transporting skeleton and a first hole-transporting skeleton, and the second organic compound preferably has a second electron-transporting skeleton and a second hole-transporting skeleton.

[0017] In each of the above structures, the difference between the LUMO energy level of the first organic compound and the LUMO energy level of the second organic compound is preferably greater than 0 eV and 0.3 eV or less.

[0018] In addition, in the above structure, the first electron-transporting skeleton and the second electron-transporting skeleton are preferably any one of a π-electron-deficient aromatic heterocycle, an arylborane skeleton, and a phosphine oxide skeleton, and the first hole-transporting skeleton and the second hole-transporting skeleton are preferably a π-electron-rich aromatic heterocycle or an aromatic amine skeleton.

[0019] In the above structure, the first electron-transporting skeleton is preferably a nitrogen-containing aromatic heterocycle having 8 to 18 carbon atoms, and the second electron-transporting skeleton is preferably a nitrogen-containing aromatic heterocycle having 3 to 8 carbon atoms.

[0020] In each of the above structures, the first hole-transporting skeleton preferably has a π-electron-rich aromatic heterocycle, and the second hole-transporting skeleton preferably has an aromatic amine skeleton (particularly a triarylamine skeleton).

[0021] In addition, in each of the above structures, the second organic compound is preferably an organic compound represented by the following structural formulas (100) to (109).

[0022]

[0023]

[0024]

[0025] In each of the above structures, the exciplex preferably has a function of transferring excitation energy to the guest material.

[0026] In each of the above structures, the guest material preferably contains iridium.

[0027] Another embodiment of the present invention is an organic compound represented by the above structural formulas (100) to (109).

[0028] Another embodiment of the present invention is a light-emitting element comprising one or more of the organic compounds represented by the above structural formulas (100) to (109).

[0029] Another embodiment of the present invention is: a display device including a light-emitting element having each of the above structures, and a color filter, a sealant or a transistor; an electronic device having the display device, and a frame or a touch sensor; a lighting device including a light-emitting element having each of the above structures, and a frame or a touch sensor. In addition, one embodiment of the present invention includes not only a light-emitting device having a light-emitting element, but also an electronic device having a light-emitting device within its scope. Therefore, the light-emitting device in this specification refers to an image display device or a light source (including a lighting device). In addition, the light-emitting device is sometimes included in the following modules: a module in which a connector such as an FPC (Flexible Printed Circuit) or a TCP (Tape Carrier Package) is installed on the light-emitting element; a module in which a printed circuit board is provided in the end of the TCP; or a module in which an IC (integrated circuit) is directly mounted on the light-emitting element by a COG (Chip On Glass) method.

[0030] According to one embodiment of the present invention, a novel light-emitting element comprising a phosphorescent material can be provided. In particular, according to one embodiment of the present invention, a light-emitting element with high luminous efficiency can be provided. According to one embodiment of the present invention, a light-emitting element with reduced voltage can be provided. Furthermore, according to one embodiment of the present invention, a light-emitting element with high reliability can be provided.

[0031] Furthermore, according to one embodiment of the present invention, a low-power-consuming light-emitting element can be provided. Furthermore, according to one embodiment of the present invention, a novel light-emitting device can be provided. Furthermore, according to one embodiment of the present invention, a novel display device can be provided.

[0032] Note that the description of these effects does not preclude the existence of other effects. Furthermore, effects other than these effects may be obvious from the description of the specification, drawings, claims, etc., and may be extracted from the description of the specification, drawings, claims, etc. Furthermore, effects other than the effects described above may be known and inferred from the description of the specification, drawings, claims, etc. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] Figures 1A to 1C 1 is a schematic cross-sectional view illustrating a light-emitting element according to one embodiment of the present invention and a diagram showing the relationship between energy levels;

[0034] Figures 2A to 2C is a diagram illustrating energy level correlation in a light-emitting layer of a light-emitting element according to one embodiment of the present invention;

[0035] Figure 3 is a schematic cross-sectional view of a light-emitting element according to one embodiment of the present invention;

[0036] Figure 4A and Figure 4B is a schematic diagram of an active matrix light-emitting device according to one embodiment of the present invention;

[0037] Figure 5A and Figure 5B is a schematic diagram of an active matrix light-emitting device according to one embodiment of the present invention;

[0038] Figure 6 is a schematic diagram of an active matrix light-emitting device according to one embodiment of the present invention;

[0039] Figure 7A 、 Figure 7B1 and Figure 7B2 is a schematic diagram of a display device according to one embodiment of the present invention;

[0040] Figure 8 is a circuit diagram of a display device according to one embodiment of the present invention;

[0041] Figure 9A and Figure 9B is a circuit diagram of a display device according to one embodiment of the present invention;

[0042] Figure 10 is a schematic diagram of a display device according to one embodiment of the present invention;

[0043] Figure 11 is a schematic diagram of a display device according to one embodiment of the present invention;

[0044] Figure 12 is a schematic diagram of a display device according to one embodiment of the present invention;

[0045] Figures 13A to 13G is a schematic diagram of an electronic device according to one embodiment of the present invention;

[0046] Figures 14A to 14E is a schematic diagram of an electronic device according to one embodiment of the present invention;

[0047] Figures 15A to 15E is a schematic diagram of an electronic device according to one embodiment of the present invention;

[0048] 16A to 16D is a schematic diagram of an electronic device according to one embodiment of the present invention;

[0049] 17A to 17C is a diagram illustrating a lighting device according to one embodiment of the present invention;

[0050] Figure 18 is a diagram illustrating a lighting device according to one embodiment of the present invention;

[0051] Figure 19A and Figure 19B is a diagram illustrating NMR spectra of compounds according to Examples;

[0052] Figure 20 are graphs illustrating absorption and emission spectra of compounds according to Examples;

[0053] Figure 21 are graphs illustrating absorption and emission spectra of compounds according to Examples;

[0054] Figure 22A and Figure 22B is a diagram illustrating NMR spectra of compounds according to Examples;

[0055] Figure 23 are graphs illustrating absorption and emission spectra of compounds according to Examples;

[0056] Figure 24 are graphs illustrating absorption and emission spectra of compounds according to Examples;

[0057] Figure 25A and Figure 25B is a diagram illustrating NMR spectra of compounds according to Examples;

[0058] Figure 26 are graphs illustrating absorption and emission spectra of compounds according to Examples;

[0059] Figure 27 are graphs illustrating absorption and emission spectra of compounds according to Examples;

[0060] Figure 28A and Figure 28Bis a diagram illustrating NMR spectra of compounds according to Examples;

[0061] Figure 29 are graphs illustrating absorption and emission spectra of compounds according to Examples;

[0062] Figure 30 are graphs illustrating absorption and emission spectra of compounds according to Examples;

[0063] Figure 31A and Figure 31B is a diagram illustrating NMR spectra of compounds according to Examples;

[0064] Figure 32 are graphs illustrating absorption and emission spectra of compounds according to Examples;

[0065] Figure 33 are graphs illustrating absorption and emission spectra of compounds according to Examples;

[0066] Figure 34A and Figure 34B is a diagram illustrating NMR spectra of compounds according to Examples;

[0067] Figure 35 are graphs illustrating absorption and emission spectra of compounds according to Examples;

[0068] Figure 36 are graphs illustrating absorption and emission spectra of compounds according to Examples;

[0069] Figure 37A and Figure 37B is a diagram illustrating NMR spectra of compounds according to Examples;

[0070] Figure 38 are graphs illustrating absorption and emission spectra of compounds according to Examples;

[0071] Figure 39 are graphs illustrating absorption and emission spectra of compounds according to Examples;

[0072] Figure 40A and Figure 40B is a diagram illustrating NMR spectra of compounds according to Examples;

[0073] Figure 41 are graphs illustrating absorption and emission spectra of compounds according to Examples;

[0074] Figure 42 are graphs illustrating absorption and emission spectra of compounds according to Examples;

[0075] Figure 43A and Figure 43B is a diagram illustrating NMR spectra of compounds according to Examples;

[0076] Figure 44 are graphs illustrating absorption and emission spectra of compounds according to Examples;

[0077] Figure 45A and Figure 45B is a diagram illustrating NMR spectra of compounds according to Examples;

[0078] Figure 46 are graphs illustrating absorption and emission spectra of compounds according to Examples;

[0079] Figure 47 are graphs illustrating absorption and emission spectra of compounds according to Examples;

[0080] Figure 48 is a schematic diagram of a light emitting element according to an embodiment;

[0081] Figure 49 is a graph illustrating current efficiency-luminance characteristics of a light-emitting element according to an embodiment;

[0082] Figure 50 is a diagram illustrating luminance-voltage characteristics of a light-emitting element according to an embodiment;

[0083] Figure 51 is a graph illustrating current density-voltage characteristics of a light emitting element according to an embodiment;

[0084] Figure 52 is a graph illustrating external quantum efficiency-luminance characteristics of a light-emitting element according to an embodiment;

[0085] Figure 53 is a diagram illustrating an emission spectrum of a light-emitting element according to an embodiment;

[0086] Figure 54 is a diagram illustrating the relationship between the driving voltage and the LUMO energy level difference between the host materials according to the embodiment;

[0087] Figure 55 is a graph illustrating current efficiency-luminance characteristics of a light-emitting element according to an embodiment;

[0088] Figure 56 is a diagram illustrating luminance-voltage characteristics of a light-emitting element according to an embodiment;

[0089] Figure 57 is a graph illustrating current density-voltage characteristics of a light emitting element according to an embodiment;

[0090] Figure 58is a graph illustrating external quantum efficiency-luminance characteristics of a light-emitting element according to an embodiment;

[0091] Figure 59 is a diagram illustrating an emission spectrum of a light-emitting element according to an embodiment;

[0092] Figure 60 is a diagram illustrating the relationship between the driving voltage and the LUMO energy level difference between the host materials according to the embodiment;

[0093] Figure 61 is a diagram illustrating reliability test results of a light emitting element according to an embodiment;

[0094] Figure 62 is a graph illustrating current efficiency-luminance characteristics of a light-emitting element according to an embodiment;

[0095] Figure 63 is a diagram illustrating luminance-voltage characteristics of a light-emitting element according to an embodiment;

[0096] Figure 64 is a graph illustrating current density-voltage characteristics of a light emitting element according to an embodiment;

[0097] Figure 65 is a graph illustrating external quantum efficiency-luminance characteristics of a light-emitting element according to an embodiment;

[0098] Figure 66 is a diagram illustrating an emission spectrum of a light-emitting element according to an embodiment;

[0099] Figure 67 is a graph illustrating current efficiency-luminance characteristics of a light-emitting element according to an embodiment;

[0100] Figure 68 is a diagram illustrating luminance-voltage characteristics of a light-emitting element according to an embodiment;

[0101] Figure 69 is a graph illustrating current density-voltage characteristics of a light emitting element according to an embodiment;

[0102] Figure 70 is a graph illustrating external quantum efficiency-luminance characteristics of a light-emitting element according to an embodiment;

[0103] Figure 71 is a diagram illustrating an emission spectrum of a light-emitting element according to an embodiment;

[0104] Figure 72 is a diagram illustrating reliability test results of a light emitting element according to an embodiment;

[0105] Figure 73 is a graph illustrating current efficiency-luminance characteristics of a light-emitting element according to an embodiment;

[0106] Figure 74 is a diagram illustrating luminance-voltage characteristics of a light-emitting element according to an embodiment;

[0107] Figure 75 is a graph illustrating current density-voltage characteristics of a light emitting element according to an embodiment;

[0108] Figure 76 is a graph illustrating external quantum efficiency-luminance characteristics of a light-emitting element according to an embodiment;

[0109] Figure 77 Graphs illustrating emission spectra of light-emitting elements according to examples.

[0110] The selection diagram of the present invention is Figures 2A to 2C . DETAILED DESCRIPTION

[0111] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Note that the present invention is not limited to the following description, and its embodiments and details may be modified in various forms without departing from the spirit and scope of the present invention. Therefore, the present invention should not be construed as being limited to the contents described in the embodiments shown below.

[0112] Furthermore, for ease of understanding, the positions, sizes, and ranges of various structures shown in the drawings and the like may not necessarily represent their actual positions, sizes, and ranges. Therefore, the disclosed invention is not necessarily limited to the positions, sizes, and ranges disclosed in the drawings and the like.

[0113] In addition, in this specification and other documents, ordinal numbers such as "first" and "second" are used for convenience, but these numbers do not necessarily indicate the order of steps or the order of stacking. Therefore, for example, "first" can be appropriately replaced with "second" or "third" for description. In addition, the ordinal numbers described in this specification and other documents may not be consistent with the ordinal numbers used to designate an embodiment of the present invention.

[0114] Note that in this specification and the like, when describing the configuration of the invention using drawings, reference numerals may be used in common to represent the same components in different drawings.

[0115] In this specification, "film" and "layer" may be interchanged. For example, a "conductive layer" may be referred to as a "conductive film." Also, an "insulating film" may be referred to as an "insulating layer."

[0116] In this specification, the singlet excited state (S *) refers to a singlet state having excitation energy. In addition, the S1 energy level is the lowest energy level of the singlet excitation energy level and refers to the excitation energy level of the lowest singlet excitation state. In addition, the triplet excited state (T * ) refers to a triplet state having excitation energy. In addition, the T1 energy level is the lowest energy level of the triplet excited energy level and refers to the excitation energy level of the lowest triplet excited state. In addition, in this specification, even if it is expressed as "singlet excited state" or "singlet excited energy level", it may refer to the lowest singlet excited state or S1 energy level. In addition, even if it is expressed as "triplet excited state" or "triplet excited energy level", it may refer to the lowest triplet excited state or T1 energy level.

[0117] In this specification, a fluorescent material refers to a material that emits light in the visible light region when returning from a singlet excited state to a ground state. A phosphorescent material refers to a material that emits light in the visible light region at room temperature when returning from a triplet excited state to a ground state. In other words, a phosphorescent material is a material that can convert triplet excitation energy into visible light.

[0118] Furthermore, the phosphorescence energy or triplet excited state energy can be derived from the wavelength of the emission peak (including the shoulder) on the shortest wavelength side of the phosphorescence. Furthermore, the phosphorescence can be observed by time-resolved photoluminescence spectroscopy at low temperatures (e.g., 10K). Furthermore, the emission energy of thermally activated delayed fluorescence can be derived from the wavelength of the emission peak (including the shoulder) on the shortest wavelength side of the thermally activated delayed fluorescence.

[0119] In this specification and the like, room temperature refers to any temperature between 0°C and 40°C.

[0120] In this specification, etc., the blue wavelength region refers to the wavelength region of 400 nm to less than 500 nm, and blue luminescence is luminescence having at least one emission spectrum peak in this region. Furthermore, the green wavelength region refers to the wavelength region of 500 nm to less than 580 nm, and green luminescence is luminescence having at least one emission spectrum peak in this region. Furthermore, the red wavelength region refers to the wavelength region of 580 nm to less than 680 nm, and red luminescence is luminescence having at least one emission spectrum peak in this region.

[0121] In this specification, bipolar materials refer to organic compounds that possess both hole-transporting and electron-transporting properties, and have both an electron-transporting skeleton and a hole-transporting skeleton in a single molecule. Examples of the electron-transporting skeleton include π-electron-deficient aromatic heterocycles, while examples of the hole-transporting skeleton include amine skeletons or π-electron-rich aromatic heterocycles.

[0122] Implementation Method 1

[0123] In this embodiment, referring to Figures 1A to 2BA light-emitting element according to one embodiment of the present invention will be described.

[0124] <Structural Example 1 of Light-Emitting Element>

[0125] First, we will refer to Figure 1A 、 Figure 1B and Figure 1C The structure of a light-emitting element according to one embodiment of the present invention will be described.

[0126] Figure 1A 1 is a schematic cross-sectional view of a light-emitting element 150 according to one embodiment of the present invention.

[0127] The light-emitting element 150 includes a pair of electrodes (electrode 101 and electrode 102 ) and an EL layer 100 provided between the pair of electrodes. The EL layer 100 includes at least a light-emitting layer 140 .

[0128] also, Figure 1A The EL layer 100 shown includes functional layers such as a hole injection layer 111 , a hole transport layer 112 , an electron transport layer 118 , and an electron injection layer 119 in addition to the light-emitting layer 140 .

[0129] Note that although in this embodiment, electrode 101 of a pair of electrodes is described as an anode and electrode 102 as a cathode, the structure of light-emitting element 150 is not limited to this. In other words, electrode 101 may serve as a cathode and electrode 102 as an anode, with the layers stacked in reverse order between the electrodes. In other words, the hole injection layer 111, hole transport layer 112, light-emitting layer 140, electron transport layer 118, and electron injection layer 119 may be stacked in this order from the anode side.

[0130] Note that the structure of the EL layer 100 is not limited to Figure 1A The structure shown may include at least one selected from the group consisting of the hole-injection layer 111, the hole-transport layer 112, the electron-transport layer 118, and the electron-injection layer 119. Alternatively, the EL layer 100 may include a functional layer capable of lowering the injection barrier for holes or electrons, improving the transportability of holes or electrons, hindering the transportability of holes or electrons, or suppressing quenching caused by electrodes. The functional layer may be a single layer or a stack of multiple layers.

[0131] Figure 1B It shows Figure 1A FIG. 1 is a schematic cross-sectional view of an example of the light-emitting layer 140 . Figure 1B The light emitting layer 140 shown includes a host material 141 and a guest material 142. In addition, the host material 141 includes an organic compound 141_1 and an organic compound 141_2.

[0132] Alternatively, a light-emitting organic material can be used as the guest material 142. Examples of the light-emitting organic material include materials that emit fluorescence (hereinafter also referred to as fluorescent materials) and materials that emit phosphorescence (hereinafter also referred to as phosphorescent materials). The following description describes a structure in which a phosphorescent material is used as the guest material 142. Note that the guest material 142 may also be referred to as a phosphorescent material.

[0133] When Figure 1B When two host materials, organic compound 141_1 and organic compound 141_2, are used as the light-emitting layer (co-host), one of the two host materials is typically an electron-transporting material and the other is a hole-transporting material. This structure is preferred because it reduces the hole injection barrier between the hole-transporting layer 112 and the light-emitting layer 140, and the electron injection barrier between the electron-transporting layer 118 and the light-emitting layer 140, thereby lowering the driving voltage.

[0134] <Light Emitting Mechanism of Light Emitting Element>

[0135] Next, the light emitting mechanism of the light emitting layer 140 will be described below.

[0136] The organic compound 141_1 and the organic compound 141_2 included in the host material 141 in the light-emitting layer 140 form an exciplex.

[0137] Figure 1C The energy level correlation of the organic compound 141_1, the organic compound 141_2, and the guest material 142 in the light-emitting layer 140 is shown. Note that Figure 1C The descriptions and symbols in are as follows.

[0138] Host (141_1): Organic compound 141_1 (host material)

[0139] Host (141_2): Organic compound 141_2 (host material)

[0140] Guest (142): Guest material 142 (phosphorescent compound)

[0141] ·S PH1 : S1 energy level of organic compound 141_1 (host material)

[0142] ·T PH1 : T1 level of organic compound 141_1 (host material)

[0143] ·S PH2 : S1 energy level of organic compound 141_2 (host material)

[0144] ·T PH2: T1 energy level of organic compound 141_2 (host material)

[0145] ·S PG : S1 energy level of guest material 142 (phosphorescent compound)

[0146] ·T PG : T1 energy level of guest material 142 (phosphorescent compound)

[0147] ·S PE : S1 energy level of the exciplex

[0148] ·T PE : T1 energy level of the exciplex

[0149] The organic compound 141_1 forms an exciplex with the organic compound 141_2. The S1 energy level (S PE ) and T1 energy level (T PE ) become adjacent energy levels (refer to Figure 1C path E1).

[0150] When one of the organic compound 141_1 and the organic compound 141_2 receives a hole and the other receives an electron, an exciplex is rapidly formed. Alternatively, when one of the organic compounds 141_1 and 141_2 becomes excited, an exciplex is rapidly formed by interacting with the other. As a result, most of the excitons in the light-emitting layer 140 exist as exciplexes. The excitation energy level (S PE or T PE ) than the S1 energy level (S PH1 and S PH2 ) is low, the excited state of the host material 141 can be formed with lower excitation energy. As a result, the driving voltage of the light-emitting element can be reduced.

[0151] Then, by exciplex (S PE ) and (T PE ) is transferred to the T1 level of the guest material 142 (phosphorescent compound) to obtain light emission (refer to Figure 1C Paths E2 and E3).

[0152] The T1 energy level of the exciplex (T PE ) is preferably higher than the T1 energy level (T PG ) is high. Thus, the singlet excitation energy and triplet excitation energy of the generated exciplex can be increased from the S1 energy level (S PE ) and T1 energy level (T PE ) is transferred to the T1 energy level (T PG).

[0153] In order to efficiently transfer the excitation energy from the exciplex to the guest material 142, the T1 energy level (T PE ) is preferably equal to or lower than the T1 level (T PH1 and T PH2 ). As a result, quenching of the triplet excitation energy of the exciplex by each organic compound (the organic compound 141_1 and the organic compound 141_2) is unlikely to occur, and energy transfer from the exciplex to the guest material 142 occurs efficiently.

[0154] When the combination of organic compound 141_1 and organic compound 141_2 is a combination of a compound having hole-transporting properties and a compound having electron-transporting properties, carrier balance can be easily controlled by adjusting their mixing ratio. Specifically, the ratio of hole-transporting compound to electron-transporting compound is preferably in the range of 1:9 to 9:1 (weight ratio). Furthermore, this structure makes it easy to control carrier balance, thereby also making it easy to control the carrier recombination zone.

[0155] In this specification, the processes of the above-mentioned paths E2 and E3 are sometimes referred to as ExTET (Exciplex-Triplet Energy Transfer). In other words, in the light-emitting layer 140, the excitation energy is supplied from the exciplex to the guest material 142. In this case, it is not necessary to transfer energy from T PE To S PE The efficiency of anti-intersystem crossing and the S PE The luminescence quantum yield is high, so more materials can be selected.

[0156] The combination of organic compound 141_1 and organic compound 141_2 can be any combination as long as it is a combination that can form an excimer complex. Preferably, the highest occupied molecular orbital (HOMO) energy level and the lowest unoccupied molecular orbital (LUMO) energy level of one of organic compound 141_1 and organic compound 141_2 are lower than the HOMO energy level and LUMO energy level of the other.

[0157] The above is the technology that ExTET contributes to improving the efficiency and reliability of phosphorescent light-emitting devices and reducing the driving voltage. Since ExTET requires the formation of an exciplex, the selection of organic compounds 141_1 and 141_2 is very important.

[0158] The present inventors have discovered that the driving voltage of the light-emitting element can be further reduced by using a combination of organic compounds in which the difference in LUMO energy levels between organic compound 141_1 and organic compound 141_2 is greater than 0 eV and less than 0.5 eV. More preferably, the difference in LUMO energy levels between organic compound 141_1 and organic compound 141_2 is greater than 0 eV and less than 0.3 eV.

[0159] The HOMO and LUMO levels of organic materials are generally estimated using CV (cyclic voltammetry), photoelectron spectroscopy, optical absorption spectroscopy, inverse photoelectron spectroscopy, etc. When comparing values between materials, it is preferable to use values estimated by the same measurement.

[0160] As described above, one of organic compound 141_1 and organic compound 141_2 accepts holes, while the other accepts electrons, rapidly forming an exciplex. In a light-emitting element according to one embodiment of the present invention, preferably both organic compound 141_1 and organic compound 141_2 are bipolar materials. Because bipolar materials have both hole-transporting and electron-transporting backbones within a single molecule, they can improve carrier transport in the light-emitting layer, thereby helping to reduce the driving voltage.

[0161] When both organic compound 141_1 and organic compound 141_2 are bipolar materials, in order for organic compound 141_1 and organic compound 141_2 to form an exciplex, one of them must accept holes and the other must accept electrons. Therefore, in light-emitting layer 140, it is preferable that the hole-accepting bipolar material have a higher HOMO energy level than the electron-accepting bipolar material, and the electron-accepting bipolar material have a lower LUMO energy level than the hole-accepting bipolar material.

[0162] Here, for example, when an electron-transporting material is used as the organic compound 141_1 and a hole-transporting material is used as the organic compound 141_2, the carrier transport properties of electrons or holes in the light-emitting layer may be reduced due to the mixing ratio. In other words, a certain amount of electron-transporting material and hole-transporting material are usually required in the layer to form an exciplex. Since the electron-transporting material hinders hole transport and the hole-transporting material hinders electron transport, this sometimes leads to an increase in the driving voltage. On the other hand, when bipolar materials are used for both the organic compound 141_1 and the organic compound 141_2, since the bipolar materials have both electron-transporting and hole-transporting functions, the driving voltage can be reduced regardless of the mixing ratio.

[0163] <Structural Example 2 of Light-Emitting Element>

[0164] Figures 2A to 2C The energy relationship between the HOMO level and the LUMO level of the organic compound 141_1 and the organic compound 141_2 in the light-emitting layer 140 of the light-emitting element according to one embodiment of the present invention is shown. Figures 2A to 2C In the description, the case where the organic compound 141_1 is a bipolar material that accepts electrons and the organic compound 141_2 is a bipolar material that accepts holes is described.

[0165] Since bipolar materials have both electron transport skeletons and hole transport skeletons in the same molecule, they have good hole transport properties and electron transport properties. In addition, the LUMO energy level of bipolar materials is mostly related to the electron transport skeleton, and the HOMO energy level is mostly related to the hole transport skeleton. Therefore, by selecting a suitable skeleton, the LUMO energy level difference and HOMO energy level difference between the two bipolar materials can be adjusted. Therefore, by selecting a material with a suitable skeleton, the electron injection barrier and hole injection barrier between the two materials can be reduced. As an example, we can cite a material with Figures 2A to 2C Shown are the energy relationships for exciplex formation in combinations of bipolar materials.

[0166] Figure 2A An example of a small LUMO energy level difference between two organic materials using ExTET is shown. The LUMO energy level difference is preferably greater than 0 eV and less than 0.5 eV, and more preferably greater than 0 eV and less than 0.3 eV. Since the LUMO energy level difference is small, the electron injection barrier becomes smaller and the driving voltage can be reduced. In this case, there are no particular restrictions on the hole-transporting skeleton that constitutes the bipolar material, and the range of materials that can be selected is wider, so it is preferred. In addition, since a material with a high HOMO energy level can be selected, even if a guest material with a high HOMO energy level is used for the light-emitting layer, the guest material is not likely to become a hole-trapping material. As a result, the increase in driving voltage can be suppressed.

[0167] In order to utilize ExTET, as described above, it is necessary to make the hole-accepting bipolar material have a higher HOMO energy level than the electron-accepting bipolar material and to make the electron-accepting bipolar material have a lower LUMO energy level than the hole-accepting bipolar material.

[0168] As the electron transport skeleton in the first organic compound and the second organic compound, π-electron-deficient aromatic heterocycle, aryl borane skeleton, phosphine oxide skeleton can be cited. In particular, the π-electron-deficient aromatic heterocycle is preferably a six-membered nitrogen-containing heterocycle, specifically preferably a pyridine ring, pyridazine ring, pyrimidine ring, pyrazine ring or triazine ring. On the other hand, as the hole transport skeleton in the first organic compound and the second organic compound, π-electron-rich aromatic heterocycle or aromatic amine skeleton can be cited. In particular, the π-electron-rich aromatic heterocycle is preferably a five-membered nitrogen-containing heterocycle, specifically preferably a pyrrole ring, furan ring or thiophene ring. In particular, the aromatic amine skeleton is preferably a triarylamine skeleton. In addition, in the first organic compound and the second organic compound, an aromatic ring or aromatic heterocycle such as a benzene ring can be fused to the above-mentioned aromatic heterocycle.

[0169] In one embodiment of the present invention, the above-mentioned skeleton can be appropriately selected to appropriately select a combination of the first organic compound and the second organic compound that can utilize ExTET. Specific examples of the skeleton are given below to illustrate the combination method.

[0170] In the case of using a bipolar material to realize the combination of the material (a combination of materials that can utilize ExTET), it is preferred that the bipolar material for receiving electrons has an electron transport skeleton that is a nitrogen-containing aromatic heterocycle and a hole transport skeleton that is a π-electron-rich aromatic heterocycle. The electron transport skeleton preferably has a nitrogen-containing aromatic heterocycle having a carbon number of 8 to 18, thereby easily lowering the LUMO energy level, but is not limited thereto. In addition, as an electron transport skeleton, a quinoline skeleton, a quinazoline skeleton, a quinoxaline skeleton, a benzofuranopyrimidine skeleton is more preferred, and a dibenzoquinoxaline skeleton is further preferred. In addition, as a hole transport skeleton, a carbazole skeleton, a dibenzothiophene skeleton, and a dibenzofuran skeleton are more preferred. By having the above-mentioned hole transport skeleton, the HOMO energy level can be relatively lowered, and therefore it is preferred. In addition, in order to maintain a low HOMO energy level, it is preferred that the bipolar material for receiving electrons does not have a triarylamine skeleton.

[0171] As a bipolar material for receiving holes when using ExTET, it is preferred to use a material in which the electron transport skeleton is a nitrogen-containing aromatic heterocycle and the hole transport skeleton is an aromatic amine skeleton (especially a triarylamine skeleton). In addition, the bipolar material for receiving holes may also have a π-electron-rich aromatic heterocycle. In addition, the electron transport skeleton preferably has a nitrogen-containing aromatic heterocycle with a carbon number of 3 to 8, which can easily make the LUMO energy level higher, but is not limited to this. More specifically, a triazine skeleton or a diazine skeleton is preferred. As a diazine skeleton, a pyrimidine skeleton, a pyrazine skeleton, a quinoxaline skeleton, a dibenzoquinoxaline skeleton, a quinazoline skeleton, a benzofuranopyrimidine skeleton, etc. can be cited. The electron transport skeleton is preferably a pyrimidine skeleton. The material having the above-mentioned electron transport skeleton has a higher LUMO energy level than the above-mentioned bipolar material for receiving electrons (material with a nitrogen-containing aromatic heterocycle with a carbon number of 8 to 18). On the other hand, materials with aromatic amine skeletons tend to have higher HOMO levels than electron-accepting bipolar materials (materials with π-electron-rich aromatic heterocycles). Therefore, exciplexes can be formed between electron-accepting bipolar materials and hole-accepting bipolar materials.

[0172] As the bipolar material for accepting holes when using ExTET, compounds represented by the following structural formulae (100) to (109) can be used. The bipolar material for accepting holes is not limited to the following materials.

[0173]

[0174]

[0175]

[0176] Figure 2B An example of a small HOMO energy level difference between two organic materials (preferably bipolar materials) using ExTET is shown. The HOMO energy level difference is preferably greater than 0eV and less than 0.5eV, more preferably greater than 0eV and less than 0.3eV. Due to the small HOMO energy level difference, the hole injection barrier becomes smaller and the driving voltage can be reduced. When a bipolar material is used in the above structure, there is no particular restriction on the electron transport skeleton constituting the bipolar material and the range of materials that can be selected is wider, so it is preferred. In addition, since a material with a low LUMO energy level can be selected, even if a guest material with a low LUMO energy level is used for the light-emitting layer, the guest material is not likely to become an electron-trapping material. Therefore, the increase in driving voltage can be suppressed.

[0177] Figure 2CAn example of using ExTET to minimize the HOMO and LUMO energy level differences between two organic materials (preferably bipolar materials) is shown. Small LUMO and HOMO energy level differences lower the electron and hole injection barriers, allowing for lower drive voltages.

[0178] <Materials>

[0179] Next, components of a light-emitting element according to one embodiment of the present invention will be described in detail below.

[0180] Luminous Layer

[0181] In the material weight ratio of light-emitting layer 140, host material 141 accounts for the largest proportion, and guest material 142 (phosphorescent material) is dispersed in host material 141. The T1 energy level of host material 141 (organic compound 141_1 and organic compound 141_2) of light-emitting layer 140 is preferably higher than the T1 energy level of the guest material (guest material 142) of light-emitting layer 140.

[0182] As the organic compound 141_1, a material with a high electron-transporting property can be used, preferably a material with a 1×10 -6 cm 2 / Vs or more electron mobility. As a material that easily receives electrons (material with electron transport properties), nitrogen-containing heteroaromatic compounds and compounds including π-electron-deficient aromatic heterocyclic skeletons and zinc or aluminum metal complexes can be used. In particular, nitrogen-containing aromatic heterocycles are preferred. 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.

[0183] Specifically, examples of metal complexes having a quinoline skeleton or a benzoquinoline skeleton include tris(8-hydroxyquinolinato)aluminum(III) (abbreviated as Alq), tris(4-methyl-8-hydroxyquinolinato)aluminum(III) (abbreviated as Almq3), bis(10-hydroxybenzo[h]quinolinato)beryllium(II) (abbreviated as BeBq2), bis(2-methyl-8-hydroxyquinolinato)(4-phenylphenol)aluminum(III) (abbreviated as BAlq), and bis(8-hydroxyquinolinato)zinc(II) (abbreviated as Znq). Furthermore, metal complexes having oxazolyl or thiazole ligands, such as bis[2-(2-benzoxazolyl)phenol]zinc(II) (abbreviated as ZnPBO) and bis[2-(2-benzothiazolyl)phenol]zinc(II) (abbreviated as ZnBTZ), can also be used. Furthermore, in addition to the metal complex, 2-(4-biphenyl)-5-(4-tert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 1,3-bis[5-(p-tert-butylphenyl)-1,3,4-oxadiazol-2-yl]benzene (abbreviation: OXD-7), 9-[4-(5-phenyl-1,3,4-oxadiazol-2-yl)phenyl]-9H-carbazole (abbreviation: CO11), 3-(4-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 (abbreviated as CzTAZ1), 2,2',2"-(1,3,5-benzenetriyl)tris(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), bathocuproin (abbreviated as BCP), and other heterocyclic compounds;2-[3-(Dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviated as 2mDBTPDBq-II), 2-[3'-(Dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviated as 2mDBTBPDBq-II), 2-[3'-(9H-carbazol-9-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviated as 2mCzBPDBq), 2-[4-(3,6-diphenyl-9H-carbazol-9-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviated as 2mCzBPDBq), phenyl]dibenzo[f,h]quinoxaline (abbreviated as: 2CzPDBq-III), 7-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviated as: 7mDBTPDBq-II), 6-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviated as: 6mDBTPDBq-II), 2-[3-(3,9'-bi-9H-carbazol-9-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviated as: 2mCz CzPDBq), 4,6-bis[3-(phenanthrene-9-yl)phenyl]pyrimidine (abbreviated as: 4,6mPnP2Pm), 4,6-bis[3-(4-dibenzothienyl)phenyl]pyrimidine (abbreviated as: 4,6mDBTP2Pm-II), 4,6-bis[3-(9H-carbazol-9-yl)phenyl]pyrimidine (abbreviated as: 4,6mCzP2Pm); heterocyclic compounds having a diazine skeleton, such as 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H-carbazol-9-yl]pyrimidine (abbreviated as: 4,6mPnP2Pm), 4,6-bis[3-(4-dibenzothienyl)phenyl]pyrimidine (abbreviated as: 4,6mDBTP2Pm-II), and 4,6-bis[3-(9H-carbazol-9-yl)phenyl]pyrimidine (abbreviated as: 4,6mCzP2Pm); ]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviated as: PCCzPTzn) and other heterocyclic compounds having a triazine skeleton; 3,5-bis[3-(9H-carbazol-9-yl)phenyl]pyridine (abbreviated as: 35DCzPPy), 1,3,5-tris[3-(3-pyridyl)phenyl]benzene (abbreviated as: TmPyPB) and other heterocyclic compounds having a pyridine skeleton; 4,4'-bis(5-methylbenzoxazolyl-2-yl)stilbene (abbreviated as: BzOs) and other heteroaromatic compounds. Among the above heterocyclic compounds, heterocyclic compounds having a triazine skeleton, a diazine (pyrimidine, pyrazine, pyridazine) skeleton, and a pyridine skeleton are stable and have good reliability, so they are preferred. In particular, 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 mainly have an electron mobility of 1×10; -6 cm 2Note that any substance other than the above substances may be used as long as it has a high electron-transporting property.

[0184] As the organic compound 141_2, it is preferred to use a substance that can form an exciplex with the organic compound 141_1. Specifically, the organic compound 141_2 preferably includes a skeleton with high donor properties such as a π-electron-rich aromatic heterocyclic skeleton or an aromatic amine skeleton. As compounds including a π-electron-rich aromatic heterocyclic skeleton, heteroaromatic compounds such as dibenzothiophene derivatives, dibenzofuran derivatives, and carbazole derivatives can be cited. At this time, it is preferred to select the organic compound 141_1, the organic compound 141_2, and the guest material 142 (phosphorescent material) in such a manner that the luminescence peak of the exciplex formed by the organic compound 141_1 and the organic compound 141_2 overlaps with the absorption band of the triple MLCT (metal to ligand charge transfer: metal to ligand charge transfer) transition of the guest material 142 (phosphorescent material) (specifically, the absorption band on the longest wavelength side). As a result, a light-emitting element with significantly improved luminous efficiency can be achieved. Note that when a thermally activated delayed fluorescent material is used instead of a phosphorescent material, the absorption band on the longest wavelength side is preferably an absorption band of a singlet state.

[0185] Alternatively, as the organic compound 141_2 , the following materials having a high hole-transporting property can be used.

[0186] As a material with high hole transport properties, it is preferable to use a material having a 1×10 -6 cm 2 The hole transport material may be a material with a hole mobility of 1 / Vs or higher. Specifically, aromatic amines, carbazole derivatives, aromatic hydrocarbons, stilbene derivatives, etc. may be used. The hole transport material may also be a polymer compound.

[0187] As materials with high hole-transporting properties, specifically, as aromatic amine compounds, there can be mentioned N,N'-di(p-tolyl)-N,N'-diphenyl-p-phenylenediamine (abbreviated as: DTDPPA), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl (abbreviated as: DPAB), N,N'-bis{4-[bis(3-methylphenyl)amino]phenyl}-N,N'-diphenyl-(1,1'-biphenyl)-4,4'-diamine (abbreviated as: DNTPD), 1,3,5-tris[N-(4-diphenylaminophenyl)-N-phenylamino]benzene (abbreviated as: DPA3B), etc.

[0188] In addition, specific examples of carbazole derivatives include 3-[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviated as PCzDPA1), 3,6-bis[N-(4-diphenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviated as PCzDPA2), 3,6-bis[N-(4-diphenylaminophenyl)-N-(1-naphthyl)amino]-9-phenylcarbazole (abbreviated as PCzDPA2), and 1-naphthylamino]-3-phenylcarbazole. CzTPN2), 3-[N-(9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviated as: PCzPCA1), 3,6-bis[N-(9-phenylcarbazole-3-yl)-N-phenylamino]-9-phenylcarbazole (abbreviated as: PCzPCA2), 3-[N-(1-naphthyl)-N-(9-phenylcarbazole-3-yl)amino]-9-phenylcarbazole (abbreviated as: PCzPCN1), etc.

[0189] In addition, 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.

[0190] Examples of aromatic hydrocarbons include 2-tert-butyl-9,10-di(2-naphthyl)anthracene (abbreviation: t-BuDNA), 2-tert-butyl-9,10-di(1-naphthyl)anthracene, 9,10-bis(3,5-diphenylphenyl)anthracene (abbreviation: DPPA), 2-tert-butyl-9,10-bis(4-phenylphenyl)anthracene (abbreviation: t-BuDBA), 9,10-di(2-naphthyl)anthracene (abbreviation: DNA), 9,10-diphenylanthracene (abbreviation: DPAnth), 2-tert-butylanthracene (abbreviation: t-BuAnth), 9,10-bis(4-methyl-1-naphthyl)anthracene (abbreviation: DMNA), ), 2-tert-butyl-9,10-bis[2-(1-naphthyl)phenyl]anthracene, 9,10-bis[2-(1-naphthyl)phenyl]anthracene, 2,3,6,7-tetramethyl-9,10-di(1-naphthyl)anthracene, 2,3,6,7-tetramethyl-9,10-di(2-naphthyl)anthracene, 9,9'-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, etc. In addition to these, pentacene, coronene, etc. can also be used. Thus, it is more preferable to use a 1×10 -6 cm 2Aromatic hydrocarbons having a hole mobility of 1 / Vs or higher and 14 to 42 carbon atoms.

[0191] Note that the aromatic hydrocarbon may also have a vinyl skeleton. Examples of aromatic hydrocarbons having a vinyl group include 4,4'-bis(2,2-diphenylvinyl)biphenyl (abbreviated as DPVBi) and 9,10-bis[4-(2,2-diphenylvinyl)phenyl]anthracene (abbreviated as DPVPA).

[0192] 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.

[0193] In addition, as a material with a high hole-transporting property, 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"-tris(carbazol-9-yl)triphenylamine (abbreviated as TCTA), 4,4',4"-tris[N-(1-naphthyl)-N-phenylamino]triphenylamine (abbreviated as 1'-TNATA), 4,4',4"-tris(N,N-diphenylamino)triphenylamine (abbreviated as TDATA), 4,4',4"-tris[N-(3-methylphenyl)-N-phenylamino]triphenylamine amine (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 amine (abbreviated as: DPNF), 2-[N-(4-diphenylaminophenyl)-N-phenylamino]spiro-9,9'-bifluorene (abbreviated as: DPASF), 4-phenyl-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviated as: PCBA1BP), 4,4'-diphenyl-4"-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviated as: PCBBi1BP), 4-(1-naphthyl)-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviated as: PCBANB), 4,4'-di(1-naphthyl)-4"-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviated as: PCNBB), 4-phenyldiphenyl-(9-phenyl-9H- carbazol-3-yl)amine (abbreviation: PCA1BP), N,N'-bis(9-phenylcarbazol-3-yl)-N,N'-diphenylbenzene-1,3-diamine (abbreviation: PCA2B), N,N',N"-triphenyl-N,N',N"-tri(9-phenylcarbazol-3-yl)benzene-1,3,5-triamine (abbreviation: PCA3B), N-(4-biphenyl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-9-phenyl-9H-carbazol-3-amine (abbreviation: PCBiF), N-(1,1'-biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9-dimethyl-9H-fluoren-2-amine (abbreviation: PCBBiF), 9,9-dimethyl-N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]fluoren-2-amine (abbreviated as: PCBAF), N-phenyl-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]spiro-9,9'-bifluoren-2-amine (abbreviated as: PCBASF), 2-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]spiro-9,9'-bifluoren-2-amine (abbreviated as: PCASF), 2,7 -Bis[N-(4-diphenylaminophenyl)-N-phenylamino]-spiro-9,9'-bifluorene (abbreviation: DPA2SF), N-[4-(9H-carbazol-9-yl)phenyl]-N-(4-phenyl)phenylaniline (abbreviation: YGA1BP), N,N'-bis[4-(carbazol-9-yl)phenyl]-N,N'-diphenyl-9,9-dimethylfluorene-2,7-diamine (abbreviation: YGA2F) and other aromatic amine compounds, 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. Abbreviation: CzTP), 3,6-bis(9H-carbazol-9-yl)-9-phenyl-9H-carbazole (abbreviation: PhCzGI), 2,8-bis(9H-carbazol-9-yl)-dibenzothiophene (abbreviation: Cz2DBT), 4-{3-[3-(9-phenyl-9H-fluorene-9-yl)phenyl]phenyl}dibenzofuran (abbreviation: mmDBFFLBi-II), 4,4',4"-(benzene-1,3,5-triyl)tribenzofuran (dibenzofuran) (abbreviation: DBF3P-II), 1,3,5-tris(dibenzothiophene-4-yl)-benzene (abbreviation: DBT3P-II), 2,8-diphenyl-4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]dibenzothiophene (abbreviation: DBTFLP-III), 4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]-6-phenyldibenzothiophene (abbreviation: DBTFLP-IV), 4-[3-(triphenylene-2-yl)phenyl]dibenzothiophene (abbreviation: mDBTPTp-II) and other amine compounds, carbazole compounds, thiophene compounds, furan compounds, fluorene compounds, triphenylene compounds, phenanthrene compounds, etc. Among them, compounds with pyrrole skeletons, furan skeletons, thiophene skeletons, and aromatic amine skeletons are stable and have good reliability, so they are preferred. Compounds with the above skeletons have high hole transport properties and also help to reduce the driving voltage.

[0194] Examples of guest material 142 (phosphorescent material) include organometallic complexes or metal complexes of iridium, rhodium, and platinum. Preferred are organic iridium complexes, such as ortho-metal complexes of iridium. Examples of ortho-metallated ligands include 4H-triazole ligands, 1H-triazole ligands, imidazole ligands, pyridine ligands, pyrimidine ligands, pyrazine ligands, and isoquinoline ligands. Examples of metal complexes include platinum complexes with porphyrin ligands.

[0195] Furthermore, as guest material 142 (phosphorescent material), organic compound 141_1, organic compound 141_2, and guest material 142 (phosphorescent material) are preferably selected so that the LUMO energy level of guest material 142 (phosphorescent material) is lower than the LUMO energy level of organic compound 141_1, and the HOMO energy level of guest material 142 (phosphorescent material) is lower than the HOMO energy level of organic compound 141_2. This allows the manufacture of a light-emitting element that has high luminous efficiency and can be driven at a low voltage.

[0196] As substances having a blue or green emission peak, for example, tris{2-[5-(2-methylphenyl)-4-(2,6-dimethylphenyl)-4H-1,2,4-triazol-3-yl-κN2]phenyl-κC}iridium(III) (abbreviated as Ir(mpptz-dmp)3), tris(5-methyl-3,4-diphenyl-4H-1,2,4-triazole)iridium(III) (abbreviated as Ir(Mpt)3), z)3), tris[4-(3-biphenyl)-5-isopropyl-3-phenyl-4H-1,2,4-triazole]iridium(III) (abbreviated as: Ir(iPrptz-3b)3), tris[3-(5-biphenyl)-5-isopropyl-4-phenyl-4H-1,2,4-triazole]iridium(III) (abbreviated as: Ir(iPr5btz)3), etc. having a 4H-triazole skeleton; tris[3-methyl-1 -(2-methylphenyl)-5-phenyl-1H-1,2,4-triazole]iridium(III) (abbreviated as: Ir(Mptz1-mp)3), tris(1-methyl-5-phenyl-3-propyl-1H-1,2,4-triazole)iridium(III) (abbreviated as: Ir(Prptz1-Me)3), etc. having a 1H-triazole skeleton; fac-tris[1-(2,6-diisopropylphenyl)-2-phenyl-1H-imidazole]iridium(III) (abbreviated as: Ir(iPrpmi)3), tris[3-(2,6-dimethylphenyl)-7-methylimidazo[1,2-f]phenanthridinato]iridium(III) (abbreviated as: Ir(dmpimpt-Me)3), etc. having an imidazole skeleton; and bis[2-(4',6'-difluorophenyl)pyridinium-N,C 2'] iridium (III) tetrakis (1-pyrazolyl) borate (abbreviated as: FIr6), bis [2- (4', 6'-difluorophenyl) pyridinium-N, C 2 '] iridium (III) picolinate (abbreviated as: FIrpic), bis{2-[3', 5'-bis(trifluoromethyl)phenyl]pyridinium-N, C 2 '}iridium (III) picolinate (abbreviated as: Ir(CF3ppy)2(pic)), bis[2-(4',6'-difluorophenyl)pyridinium-N,C 2 Organometallic iridium complexes with phenylpyridine derivatives having electron-withdrawing groups as ligands, such as iridium (III) acetylacetonate (abbreviated as FIr(acac)). Among these metal complexes, organometallic iridium complexes with nitrogen-containing five-membered heterocyclic skeletons, such as 4H-triazole, 1H-triazole, and imidazole, are particularly preferred due to their high triplet excitation energy, excellent reliability, and excellent luminous efficiency.

[0197] Examples of substances having a green or yellow emission peak include tris(4-methyl-6-phenylpyrimidinyl)iridium(III) (abbreviation: Ir(mppm)3), tris(4-tert-butyl-6-phenylpyrimidinyl)iridium(III) (abbreviation: Ir(tBuppm)3), (acetylacetonate)bis(6-methyl-4-phenylpyrimidinyl)iridium(III) (abbreviation: Ir(mppm)2(acac)), (acetylacetonate)bis(6-tert-butyl-4-phenylpyrimidinyl)iridium(III) (abbreviation: Ir(tBuppm)2(acac)), (acetylacetonate)bis(4-(2-norbornyl)-6-phenylpyrimidinyl]iridium(III) (abbreviation: Ir(nbppm)2(acac)), (acetylacetonate)bis[5-methyl-6-(2-methylphenyl)-4-phenylpyrimidinyl]iridium(III) (abbreviation: Ir(mpppm)2(acac)). mppm)2(acac)), (acetylacetonato)bis{4,6-dimethyl-2-[6-(2,6-dimethylphenyl)-4-pyrimidinyl-κN3]phenyl-κC}iridium(III) (abbreviation: Ir(dmppm-dmp)2(acac)), (acetylacetonato)bis(4,6-diphenylpyrimidinyl)iridium(III) (abbreviation: Ir(dppm)2(acac)), organometallic iridium complexes having a pyrazine skeleton such as (acetylacetonato)bis(3,5-dimethyl-2-phenylpyrazine)iridium(III) (abbreviation: Ir(mppr-Me)2(acac)), (acetylacetonato)bis(5-isopropyl-3-methyl-2-phenylpyrazine)iridium(III) (abbreviation: Ir(mppr-iPr)2(acac)), tris(2-phenylpyridinyl-N,C 2') Iridium (III) (abbreviated as: Ir(ppy)3), bis(2-phenylpyridinium-N, C 2 ') iridium (III) acetylacetonate (abbreviated as: Ir(ppy)2(acac)), bis(benzo[h]quinolinol)iridium (III) acetylacetonate (abbreviated as: Ir(bzq)2(acac)), tris(benzo[h]quinolinol)iridium (III) (abbreviated as: Ir(bzq)3), tris(2-phenylquinolinol-N,C 2′ )iridium (III) (abbreviated as: Ir(pq)3), bis(2-phenylquinoline-N, C 2 ') Iridium (III) acetylacetonate (abbreviated as: Ir (pq) 2 (acac)) and other organometallic iridium complexes with pyridine skeleton, bis (2,4-diphenyl-1,3-oxazole-N, C 2 ') iridium (III) acetylacetonate (abbreviated as: Ir(dpo)2(acac)), bis{2-[4'-(perfluorophenyl)phenyl]pyridine-N, C 2 '}Iridium (III) acetylacetonate (abbreviated as: Ir(p-PF-ph)2(acac)), bis(2-phenylbenzothiazole-N, C 2 ') Organometallic iridium complexes such as iridium(III) acetylacetonate (abbreviated as Ir(bt)2(acac)), and rare earth metal complexes such as terbium(III) tris(acetylacetonate)(monophenanthroline) (abbreviated as Tb(acac)3(Phen)). Among these metal complexes, organometallic iridium complexes having a pyrimidine skeleton are particularly preferred due to their excellent reliability and luminous efficiency.

[0198] In addition, as a substance having a luminescence peak in yellow or red, for example, (diisobutyrylmethane)bis[4,6-bis(3-methylphenyl)pyrimidinyl]iridium(III) (abbreviation: Ir(5mdppm)2(dibm)), bis[4,6-bis(3-methylphenyl)pyrimidinyl](dipivaloylmethane)iridium(III) (abbreviation: Ir(5mdppm)2(dpm)), bis[4,6-di(naphthalene-1-yl)pyrimidinyl](dipivaloylmethane)iridium(III) (abbreviation: Ir(d1npm)2(dpm)), etc. can be cited. Organometallic iridium complexes with a pyrimidine skeleton; (acetylacetonato)bis(2,3,5-triphenylpyrazinato)iridium(III) (abbreviated as: Ir(tppr)2(acac)), bis(2,3,5-triphenylpyrazinato)(dipivaloylmethane)iridium(III) (abbreviated as: Ir(tppr)2(dpm)), (acetylacetonato)bis[2,3-bis(4-fluorophenyl)quinoxaline]iridium(III) (abbreviated as: Ir(Fdpq)2(acac)), etc.; Organometallic iridium complexes with a pyrazine skeleton, such as tris(1-phenylisoquinoline-N,C2’ ) iridium (III) (abbreviated as: Ir(piq)3), bis(1-phenylisoquinoline-N, C 2’ ) iridium (III) acetylacetonate (abbreviated as Ir(piq)2(acac)) and other organometallic iridium complexes with a pyridine skeleton; platinum complexes such as 2,3,7,8,12,13,17,18-octaethyl-21H,23H-porphyrin platinum (II) (abbreviated as PtOEP); and rare earth metal complexes such as tris(1,3-diphenyl-1,3-propanedione)(monophenanthroline)europium(III) (abbreviated as Eu(DBM)3(Phen)) and tris[1-(2-thenoyl)-3,3,3-trifluoroacetone](monophenanthroline)europium(III) (abbreviated as Eu(TTA)3(Phen)). Among the above metal complexes, organometallic iridium complexes with a pyrimidine skeleton are particularly preferred due to their excellent reliability and luminous efficiency. In addition, organometallic iridium complexes with a pyrazine skeleton can provide red luminescence with good chromaticity.

[0199] In addition, among the above-mentioned iridium complexes, organometallic iridium complexes having a pyrimidine skeleton or a pyrazine skeleton tend to have a low LUMO energy level due to the high electron acceptability of their ligands, and are therefore suitable for one embodiment of the present invention. In addition, compounds having electron-withdrawing substituents such as halogen groups such as fluoro groups or cyano groups (e.g., iridium complexes) also tend to have a low LUMO energy level, and are therefore suitable for one embodiment of the present invention.

[0200] As the luminescent material included in the luminescent layer 140, a material capable of converting triplet excitation energy into luminescence can be used. Examples of materials capable of converting triplet excitation energy into luminescence include, in addition to phosphorescent materials, thermally activated delayed fluorescence (TADF) materials. Therefore, the descriptions regarding phosphorescent materials can be considered as descriptions regarding thermally activated delayed fluorescence materials. Note that a thermally activated delayed fluorescence material refers to a material that has a small difference between the triplet excitation energy level and the singlet excitation energy level and has the ability to convert energy from the triplet excited state to the singlet excited state through anti-intersystem crossing. Therefore, it is possible to upconvert the triplet excited state to the singlet excited state (anti-intersystem crossing) using a small amount of thermal energy and efficiently produce luminescence (fluorescence) from the singlet excited state. Furthermore, the conditions for efficiently obtaining thermally activated delayed fluorescence are as follows: the energy difference between the triplet excitation energy level and the singlet excited state emission energy level is greater than 0 eV and less than 0.2 eV, preferably greater than 0 eV and less than 0.1 eV.

[0201] When the thermally activated delayed fluorescent material is composed of one material, for example, the following materials can be used.

[0202] First, there are fullerenes or their derivatives, acridine derivatives such as proflavine, eosin, etc. In addition, there are metal-containing porphyrins containing magnesium (Mg), zinc (Zn), cadmium (Cd), tin (Sn), platinum (Pt), indium (In), or palladium (Pd). Examples of the metal-containing porphyrin include protoporphyrin-tin fluoride complex (SnF2(Proto IX)), mesoporphyrin-tin fluoride complex (SnF2(Meso IX)), hematoporphyrin-tin fluoride complex (SnF2(Hemato IX)), coproporphyrin tetramethyl ester-tin fluoride complex (SnF2(Copro III-4Me)), octaethylporphyrin-tin fluoride complex (SnF2(OEP)), protoporphyrin-tin fluoride complex (SnF2(Etio I)), octaethylporphyrin-platinum chloride complex (PtCl2OEP), and the like.

[0203] In addition, as a thermally activated delayed fluorescent material composed of a single material, a heterocyclic compound having a π-electron-rich aromatic heterocycle and a π-electron-deficient aromatic heterocycle can also be used. Specifically, 2-(biphenyl-4-yl)-4,6-bis(12-phenylindolo[2,3-a]carbazole-11-yl)-1,3,5-triazine (abbreviated as: PIC-TRZ), 2-{4-[3-(N-phenyl-9H-carbazole-3-yl)-9H-carbazole-9-yl]phenyl}-4,6-diphenyl-1,3,5-triazine (abbreviated as: PCCzPTzn), 2-[4-(10H-phenoxazine-10-yl)phenyl]-4,6-diphenyl-1,3,5-triazine (abbreviated as: PXZ-TRZ), Examples include 3-[4-(5-phenyl-5,10-dihydrophenazin-10-yl)phenyl]-4,5-diphenyl-1,2,4-triazole (abbreviated as PPZ-3TPT), 3-(9,9-dimethyl-9H-acridin-10-yl)-9H-xanthene-9-one (abbreviated as ACRXTN), bis[4-(9,9-dimethyl-9,10-dihydroacridinium)phenyl]sulfone (abbreviated as DMAC-DPS), and 10-phenyl-10H,10'H-spiro[acridin-9,9'-anthracenes]-10'-one (abbreviated as ACRSA). These heterocyclic compounds have both π-electron-rich and π-electron-deficient aromatic heterocycles, and therefore exhibit high electron- and hole-transporting properties, making them preferred. In particular, among the skeletons having π-electron-deficient aromatic heterocycles, diazine skeletons (pyrimidine skeletons, pyrazine skeletons, pyridazine skeletons) and triazine skeletons are stable and have good reliability, so they are preferred. In addition, among the skeletons having π-electron-rich aromatic heterocycles, acridine skeletons, phenoxazine skeletons, thiophene skeletons, furan skeletons and pyrrole skeletons are stable and have good reliability, so it is preferred to have any one or more selected from these skeletons. As the pyrrole skeleton, it is particularly preferred to use an indole skeleton, a carbazole skeleton and a 3-(9-phenyl-9H-carbazole-3-yl)-9H-carbazole skeleton. In addition, in the substance in which the π-electron-rich aromatic heterocycle and the π-electron-deficient aromatic heterocycle are directly bonded, the donor property of the π-electron-rich aromatic heterocycle and the acceptor property of the π-electron-deficient aromatic heterocycle are both strong, and the difference between the singlet excitation energy level and the triplet excitation energy level becomes smaller, so it is particularly preferred.

[0204] The light-emitting layer 140 may also be formed of a plurality of layers of more than two layers. For example, in the case where the light-emitting layer 140 is formed by stacking the first light-emitting layer and the second light-emitting layer in sequence from the hole transport layer side, a substance having hole transport properties may be used as the main material of the first light-emitting layer, and a substance having electron transport properties may be used as the main material of the second light-emitting layer. In addition, the light-emitting materials contained in the first light-emitting layer and the second light-emitting layer may be the same or different materials. In addition, the light-emitting materials contained in the first light-emitting layer and the second light-emitting layer may be materials having the function of emitting light of the same color or materials having the function of emitting light of different colors. By using light-emitting materials having the function of emitting light of different colors as the two light-emitting layers, a plurality of light-emitting materials can be obtained at the same time. In particular, it is preferred to select the light-emitting materials used for each light-emitting layer so that white light emission can be obtained by combining the light emitted by the two light-emitting layers.

[0205] Furthermore, the light-emitting layer 140 may contain materials other than the host material 141 and the guest material 142 .

[0206] The light emitting layer 140 can be formed by vapor deposition (including vacuum vapor deposition), inkjet coating, coating, gravure printing, etc. In addition to the above materials, inorganic compounds such as quantum dots or high molecular compounds (oligomers, dendrimers, polymers, etc.) can also be included.

[0207] Hole injection layer

[0208] 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 using, for example, a transition metal oxide, a phthalocyanine derivative, or an aromatic amine. Examples of transition metal oxides include molybdenum oxide, vanadium oxide, ruthenium oxide, tungsten oxide, and manganese oxide. Examples of phthalocyanine derivatives include phthalocyanine or metal phthalocyanine. Examples of aromatic amines include benzidine derivatives or phenylenediamine derivatives. In addition, polymer compounds such as polythiophene or polyaniline may be used, typically poly(ethylenedioxythiophene) / poly(styrenesulfonic acid) as self-doped polythiophene.

[0209] As the hole injection layer 111, a layer of 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 a material having the property of receiving electrons and a layer containing a hole transport material can be used. In a steady state or in the presence of an electric field, charge transfer can be carried out between these materials. As materials having the property of receiving electrons, organic acceptors such as quinone dimethane derivatives, tetrachlorobenzoquinone derivatives, and hexaazatriphenylene derivatives can be cited. Specifically, compounds having electron-withdrawing groups (halogen or cyano groups) such as 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroquinodimethane (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. Molybdenum oxide is particularly preferably used because it is stable in the atmosphere, has low hygroscopicity, and is easy to handle.

[0210] 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 Specifically, aromatic amines, carbazole derivatives, aromatic hydrocarbons, stilbene derivatives, and the like, which are examples of hole-transporting materials that can be used in the light-emitting layer 140, can be used. The hole-transporting materials may also be polymer compounds.

[0211] Hole Transport Layer

[0212] The hole-transporting layer 112 is a layer containing a hole-transporting material, and the hole-transporting materials exemplified as the materials for the hole-injection layer 111 can be used. The hole-transporting layer 112 has the function of transporting holes injected into the hole-injection layer 111 to the light-emitting layer 140. Therefore, the hole-transporting layer 112 preferably has a highest occupied molecular orbital (HOMO) energy level that is the same as or close to that of the hole-injection layer 111.

[0213] In addition, it is preferred to use a 1×10 -6 cm 2 / Vs or higher. However, as long as the hole transport property is higher than the electron transport property, a substance other than the above substances can be used. In addition, the layer including the substance with high hole transport property is not limited to a single layer, and two or more layers composed of the above substances can be stacked.

[0214] Electron Transport Layer

[0215] The electron transport layer 118 has the function of transporting electrons injected from the other of the pair of electrodes (electrode 101 or electrode 102) through the electron injection layer 119 to the light-emitting layer 140. As the electron transport material, a material with a higher electron transport property than a hole transport property can be used, and preferably a material with a 1×10 -6 cm 2 / Vs or more of the electron mobility. As a compound that easily accepts electrons (material with electron transport properties), a π-electron-deficient heteroaromatic compound such as a nitrogen-containing heteroaromatic compound or a metal complex 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. In addition, it is preferably a material with 1×10 -6 cm 2 / Vs or higher. As long as the electron transport property is higher than the hole transport property, substances other than the above substances can be used. In addition, the electron transport layer 118 is not limited to a single layer, and two or more layers composed of the above substances can be stacked.

[0216] Furthermore, a layer for controlling the movement of electron carriers can be provided between the electron-transporting layer 118 and the light-emitting layer 140. This layer is formed by adding a small amount of a substance with high electron-trapping properties to the aforementioned material with high electron-transport properties. By suppressing the movement of electron carriers, the carrier balance can be adjusted. This structure is very effective in suppressing problems caused by electrons passing through the light-emitting layer (such as a reduction in device life).

[0217] Electron injection layer

[0218] The electron injection layer 119 has the function of lowering the potential barrier for electron injection from the electrode 102 and promoting 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 the above-mentioned electron transport material and a material having the property of supplying electrons to the electron transport material can also be used. As materials having electron-donating properties, Group 1 metals, Group 2 metals or their oxides can be cited. Specifically, lithium fluoride (LiF), sodium fluoride (NaF), cesium fluoride (CsF), calcium fluoride (CaF2) and lithium oxide (LiO x) or other alkali metals, alkaline earth metals, or compounds of these metals. In addition, rare earth metal compounds such as erbium fluoride (ErF3) can be used. In addition, an electron salt can also be used for the electron injection layer 119. 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, a substance that can be used for the electron transport layer 118 can also be used for the electron injection layer 119.

[0219] 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 119. 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 substances constituting the electron transport layer 118 as described above (metal complexes, heteroaromatic compounds, etc.) can be used. As an electron donor, any substance that exhibits electron-donating properties to the organic compound 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.

[0220] In addition, 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 method, coating method, gravure printing and the like. In addition, as the above-mentioned light-emitting layer, hole injection layer, hole transport layer, electron transport layer and electron injection layer, 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.

[0221] As quantum dots, colloidal quantum dots, alloy quantum dots, core-shell quantum dots, core-type quantum dots, etc. can be used. In addition, quantum dots containing elements from Group 2 and Group 16, Group 13 and Group 15, Group 13 and Group 17, Group 11 and Group 17, or Group 14 and Group 15 can also be used. Alternatively, quantum dots containing elements such as cadmium (Cd), selenium (Se), zinc (Zn), sulfur (S), phosphorus (P), indium (In), tellurium (Te), lead (Pb), gallium (Ga), arsenic (As), and aluminum (Al) can be used.

[0222] A Pair of Electrodes

[0223] The electrodes 101 and 102 serve as an anode and a cathode of the light-emitting element and can be formed using a metal, an alloy, a conductive compound, a mixture thereof, a stacked structure, or the like.

[0224] One of the electrodes 101 and 102 is preferably formed using a conductive material that has the function of reflecting light. Examples of the conductive material include aluminum (Al) or alloys containing Al. Examples of alloys containing Al include alloys containing Al and L (L represents one or more of titanium (Ti), neodymium (Nd), nickel (Ni), and lanthanum (La)), such as alloys containing Al and Ti or alloys containing Al, Ni, and La. Aluminum has low resistivity and high light reflectivity. In addition, since aluminum is abundant in the earth's crust and inexpensive, using aluminum can reduce the manufacturing cost of the light-emitting element. Alternatively, silver (Ag) or 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. Examples of alloys containing silver include 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. In addition to the above materials, transition metals such as tungsten, chromium (Cr), molybdenum (Mo), copper, and titanium can be used.

[0225] Furthermore, light obtained from the light-emitting layer is extracted through one or both of the electrodes 101 and 102. Therefore, at least one of the electrodes 101 and 102 is preferably formed using a conductive material having a light-transmitting function. Examples of such conductive materials include those 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.

[0226] Alternatively, the electrodes 101 and 102 may be formed using a conductive material having a function of transmitting light and a function of reflecting light. Examples of such conductive materials include those having a visible light reflectivity of 20% or more and 80% or less, preferably 40% or more and 70% or less, and a resistivity of 1×10 -2Ω·cm or less conductive material. For example, one or more 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 zinc oxide (Indium Zinc Oxide), indium oxide-tin oxide containing titanium, indium-titanium oxide, and indium oxide containing tungsten oxide and zinc oxide can be used. In addition, a metal film having a thickness that allows light to pass through (preferably a thickness of 1 nm or more and 30 nm or less) 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.

[0227] Note that in this specification, etc., as a material having a light-transmitting function, a material having a function of transmitting visible light and having conductivity may be used, such as the oxide conductor represented by ITO (Indium Tin Oxide), an oxide semiconductor, or an organic conductor containing an organic substance. As an organic conductor containing an organic substance, for example, a composite material containing a mixed organic compound and an electron donor (donor), a composite material containing a mixed organic compound and an electron acceptor (acceptor), etc. can be cited. Inorganic carbon materials such as graphene can also be used. In addition, the resistivity of the material is preferably 1×10 5 Ω·cm or less, more preferably 1×10 4 Ω·cm or less.

[0228] In addition, one or both of the electrode 101 and the electrode 102 may be formed by stacking a plurality of the above-mentioned materials.

[0229] In order to improve the light extraction efficiency, a material having a refractive index higher than that of an electrode can be formed in contact with an electrode having a function of transmitting light. As such a material, as long as it has the function of transmitting visible light, it can be a conductive material or a non-conductive material. For example, in addition to the above-mentioned oxide conductors, oxide semiconductors and organic substances can also be mentioned. 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 mentioned. In addition, inorganic carbon materials or metal films having a thickness that allows light to pass through can also be used. In addition, a plurality of layers having a thickness of several nm to several tens of nm can also be stacked using these materials with high refractive indexes.

[0230] When the electrode 101 or the electrode 102 is used as a cathode, a material with a small work function (3.8 eV or less) is preferably used. 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 and strontium, magnesium, etc.), alloys containing these elements (e.g., Ag and Mg or Al and Li), rare earth metals such as europium (Eu) and Yb, alloys containing these rare earth metals, alloys containing aluminum and silver, etc. can be used.

[0231] 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 higher).

[0232] Electrodes 101 and 102 may also be formed by stacking a conductive material that reflects light and a conductive material that transmits light. In this case, electrodes 101 and 102 preferably have the function of adjusting the optical distance so that the desired light from each light-emitting layer resonates and amplifies the light of that wavelength.

[0233] As a film forming method for the electrodes 101 and 102 , sputtering, vapor deposition, printing, coating, MBE (Molecular Beam Epitaxy), CVD, pulsed laser deposition, ALD (Atomic Layer Deposition), or the like can be appropriately used.

[0234] Substrate

[0235] The light-emitting element of one embodiment of the present invention can be manufactured over a substrate made of glass, plastic, etc. The layers can be stacked on the substrate in the order of sequentially stacking from the electrode 101 side or from the electrode 102 side.

[0236] In addition, as a substrate capable of forming a light-emitting element according to 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 bendable substrate, such as a plastic substrate made of polycarbonate or polyarylate. In addition, a film, an inorganic vapor-deposited film, etc. can be used. Note that other materials can be used as long as they serve as a support during the manufacturing process of the light-emitting element and the optical element. Alternatively, any material can be used as long as it has the function of protecting the light-emitting element and the optical element.

[0237] The structure described in this embodiment mode can be used in combination with other embodiment modes as appropriate.

[0238] Implementation Method 2

[0239] In this embodiment, referring to Figure 3A 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. This light-emitting element has a plurality of light-emitting units between a first electrode and a second electrode. One of the light-emitting units has the same structure as the EL layer 103 in Embodiment 1. That is, whereas the light-emitting element described in Embodiment 1 has a single light-emitting unit, the light-emitting element in this embodiment has a plurality of light-emitting units.

[0240] <Structural Example 3 of Light-Emitting Element>

[0241] Figure 3 is a schematic cross-sectional view of the light emitting element 250 .

[0242] Figure 3 The light emitting element 250 shown has a plurality of light emitting units ( Figure 3 The light emitting unit 106 and the light emitting unit 108). One of the plurality of light emitting units preferably has Figure 1A and Figure 1B The EL layer 100 has the same structure as shown. Figure 1A and Figure 1B The light-emitting element 150 shown preferably has a single light-emitting unit, while the light-emitting element 250 preferably has a plurality of light-emitting units. Note that in the light-emitting element 250, although the electrode 101 is described as an anode and the electrode 102 is a cathode, the structure of the light-emitting element 250 may also be the opposite.

[0243] In addition, Figure 3 In the light emitting element 250 shown, the light emitting unit 106 and the light emitting unit 108 are stacked, and the charge generation layer 115 is provided between the light emitting unit 106 and the light emitting unit 108. In addition, the light emitting unit 106 and the light emitting unit 108 may have the same structure or different structures. For example, it is preferable to Figure 1A and Figure 1B The EL layer 100 shown is suitable for use in the light emitting unit 108 .

[0244] Furthermore, the light-emitting element 250 includes a light-emitting layer 120 and a light-emitting layer 170. Furthermore, the light-emitting unit 106 includes, in addition to the light-emitting layer 120, a hole injection layer 111, a hole transport layer 112, an electron transport layer 113, and an electron injection layer 114. Furthermore, the light-emitting unit 108 includes, in addition to the light-emitting layer 170, a hole injection layer 116, a hole transport layer 117, an electron transport layer 118, and an electron injection layer 119.

[0245] The charge generation layer 115 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, or both structures may be stacked.

[0246] When the charge generation layer 115 includes a composite material composed of an organic compound and an acceptor substance, the composite material that can be used for the hole injection layer 111 described in Embodiment 1 can be used as the composite material. As the organic compound, various compounds such as aromatic amine compounds, carbazole compounds, aromatic hydrocarbons, and high molecular weight compounds (oligomers, dendrimers, polymers, etc.) can be used. In addition, as the organic compound, it is preferable to use an organic compound having a hole mobility of 1×10 -6 cm 2 / Vs or above. However, as long as the hole transport property is higher than the electron transport property, substances other than these can be used. Because the composite material composed 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. In addition, when the surface on the anode side of the light-emitting unit contacts the charge generation layer 115, the charge generation layer 115 can also have the function of the hole injection layer or hole transport layer of the light-emitting unit, so the light-emitting unit can also have a structure in which no hole injection layer or hole transport layer is provided. Alternatively, when the surface on the cathode side of the light-emitting unit contacts the charge generation layer 115, the charge generation layer 115 can also have the function of the electron injection layer or electron transport layer of the light-emitting unit, so the electron injection layer or electron transport layer can also be not provided in the light-emitting unit.

[0247] Note that the charge generation layer 115 may also have a stacked structure comprising a layer comprising a composite material of an organic compound and an acceptor substance, and a layer comprising another material. For example, a structure may be formed by combining a layer comprising a composite material of an organic compound and an acceptor substance, and a layer comprising one compound selected from electron-donating substances and a compound having high electron-transport properties. Alternatively, a structure may be formed by combining a layer comprising a composite material of an organic compound and an acceptor substance, and a layer comprising a transparent conductive material.

[0248] The charge generation layer 115 sandwiched between the light emitting unit 106 and the light emitting unit 108 only needs to be able to inject electrons into one light emitting unit and inject holes into the other light emitting unit when a voltage is applied between the electrode 101 and the electrode 102. Figure 3 In the embodiment, when a voltage is applied so that the potential of the electrode 101 is higher than the potential of the electrode 102 , the charge generation layer 115 injects electrons into the light-emitting unit 106 and injects holes into the light-emitting unit 108 .

[0249] From the perspective of light extraction efficiency, the charge generation layer 115 preferably has visible light transmittance (specifically, the charge generation layer 115 has a visible light transmittance of 40% or more). Furthermore, the charge generation layer 115 functions even if its conductivity is lower than that of the pair of electrodes (electrode 101 and electrode 102).

[0250] By forming the charge generation layer 115 using the above-mentioned material, an increase in driving voltage when a light-emitting layer is stacked can be suppressed.

[0251] Furthermore, by using bipolar materials for both host materials used in the light-emitting layer 140 or 170 as described in Embodiment 1 and adjusting the LUMO level or HOMO level between the bipolar materials, the driving voltage can be further reduced.

[0252] Note that the charge generation layer 115 may also be formed by employing a stacked-layer structure comprising a layer comprising a composite material of an organic compound and a metal oxide and a layer comprising another material. For example, a layer comprising a composite material of an organic compound and a metal oxide may be combined with a layer comprising a compound selected from electron-donating substances and a compound having a high electron-transporting property. Alternatively, a layer comprising a composite material of an organic compound and a metal oxide may be combined with a transparent conductive film.

[0253] In either case, the charge generation layer 115 sandwiched between the light-emitting unit 106 and the light-emitting unit 108 only needs to be able to inject electrons into one light-emitting unit and inject holes into the other light-emitting unit when a voltage is applied to the first electrode 101 and the second electrode 102. Figure 3 In the embodiment, when a voltage is applied so that the potential of the first electrode 101 is higher than the potential of the second electrode 102 , the charge generation layer 115 only needs to be able to inject electrons into the light-emitting unit 106 and inject holes into the light-emitting unit 108 .

[0254] While this embodiment describes a light-emitting element having two light-emitting units, the same structure can be applied to a light-emitting element having three or more stacked light-emitting units. As shown in the light-emitting element of this embodiment, by arranging multiple light-emitting units between a pair of electrodes, separated by a charge generation layer, it is possible to realize an element that can achieve high-brightness emission while maintaining a low current density and a longer lifetime. Furthermore, a light-emitting device that can be driven with low power consumption can be realized.

[0255] Furthermore, in each of the above-described structures, the guest materials used in light-emitting units 106 and 108 can emit light of the same or different colors. When light-emitting units 106 and 108 include guest materials capable of emitting the same color, light-emitting element 250 preferably emits light with high brightness at a low current. Furthermore, when light-emitting units 106 and 108 include guest materials capable of emitting light of different colors, light-emitting element 250 preferably emits light in multiple colors. In this case, by using multiple light-emitting materials with different emission wavelengths in one or both of light-emitting layers 120 and 170, light having different emission peaks is synthesized, resulting in an emission spectrum exhibiting at least two maxima.

[0256] The above structure is suitable for producing white light. White light can be produced by emitting layers 120 and 170 with complementary colors. It is particularly preferable to select a guest material that produces white light with high color rendering properties or at least red, green, and blue light.

[0257] Alternatively, one or both of the light-emitting layer 120 and the light-emitting layer 170 may be further divided into layers, with each of the divided layers containing a different light-emitting material. That is, one or both of the light-emitting layer 120 and the light-emitting layer 170 may be formed from two or more layers. For example, in the case of forming the light-emitting layer by stacking a first light-emitting layer and a second light-emitting layer in sequence from the hole-transporting layer side, a substance having hole-transporting properties may be used as the host material of the first light-emitting layer, and a substance having electron-transporting properties may be used as the host material of the second light-emitting layer. In this case, the light-emitting materials contained in the first and second light-emitting layers may be the same or different materials. Furthermore, the light-emitting materials contained in the first and second light-emitting layers may be materials capable of emitting light of the same color or materials capable of emitting light of different colors. By employing a structure in which multiple light-emitting materials are capable of emitting light of different colors, white light with high color rendering properties can be obtained, utilizing three primary colors or four or more light-emitting colors.

[0258] In addition, this embodiment mode can be combined with other embodiment modes as appropriate.

[0259] Implementation 3

[0260] In this embodiment, reference is made to Figure 4A and Figure 4B A light-emitting device using the light-emitting element described in Embodiments 1 and 2 will be described.

[0261] Figure 4Ais a top view showing a light emitting device, Figure 4B It is along Figure 4A AB and CD cross-sectional views in FIG. The light-emitting device includes a driver circuit portion (source-side driver circuit) 601 for controlling the light emission of the light-emitting element, a pixel portion 602, and a driver circuit portion (gate-side driver circuit) 603, indicated by dashed lines. Reference numeral 604 denotes a sealing substrate, reference numeral 625 denotes a desiccant, reference numeral 605 denotes a sealant, and the space within the space surrounded by sealant 605 is space 607.

[0262] Furthermore, the lead wiring 608 is used to transmit signals input to the source-side driver circuit 601 and the gate-side driver circuit 603, and receives video signals, clock signals, start signals, reset signals, and the like from an FPC (flexible printed circuit) 609, which serves as an external input terminal. Although only an FPC is shown here, a printed wiring board (PWB) may also be attached to the FPC. The light-emitting device in this specification includes not only the light-emitting device itself but also a light-emitting device attached with an FPC or PWB.

[0263] Next, refer to Figure 4B The cross-sectional structure of the light emitting device is described below. A driver circuit portion and a pixel portion are formed on an element substrate 610. Here, a source-side driver circuit 601 serving as the driver circuit portion and one pixel in the pixel portion 602 are shown.

[0264] In addition, a CMOS circuit combining an n-channel TFT 623 and a p-channel TFT 624 is formed in the source-side driver circuit 601. Alternatively, the driver circuit may be formed using various CMOS circuits, PMOS circuits, or NMOS circuits. Furthermore, while this embodiment shows a driver-integrated type in which the driver circuit is formed on the substrate, this configuration is not required, and the driver circuit may also be formed externally rather than on the substrate.

[0265] The pixel portion 602 is formed of a pixel 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. Furthermore, 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.

[0266] Furthermore, to improve the coverage of the film formed on the insulator 614, the upper or lower end of the insulator 614 is formed into a curved surface. For example, when a photosensitive acrylic resin is used as the material for the insulator 614, it is preferable to form a curved surface only on the upper end of the insulator 614. The radius of curvature of this curved surface is 0.2 μm or more and 3 μm or less. The insulator 614 can be made of either a negative-type photosensitive material or a positive-type photosensitive material.

[0267] An EL layer 616 and a second electrode 617 are formed over the first electrode 613. A material having a high work function is preferably used as the material for the first electrode 613, which serves as the anode. For example, in addition to single-layer films such as an ITO film, an indium tin oxide film containing silicon, an indium oxide film containing 2% to 20% by weight of zinc oxide, a titanium nitride film, a chromium film, a tungsten film, a Zn film, and a Pt film, a stacked film composed of a titanium nitride film and a film primarily composed of aluminum, and a three-layer structure composed of a titanium nitride film, a film primarily composed of aluminum, and a titanium nitride film can also be used. Note that a stacked structure also reduces wiring resistance, achieving good ohmic contact and enabling the use of the anode.

[0268] The EL layer 616 is formed by various methods such as vapor deposition using a vapor deposition mask, inkjet, and spin coating. A low molecular weight compound or a high molecular weight compound (including an oligomer and a dendrimer) may be used as a material constituting the EL layer 616.

[0269] The material of the second electrode 617, which is formed on the EL layer 616 and serves as a cathode, is preferably a material having a low work function (e.g., Al, Mg, Li, Ca, or alloys or compounds thereof, MgAg, MgIn, AlLi, etc.). Note that, in order to allow light generated in the EL layer 616 to pass through the second electrode 617, it is preferable to use a stacked-layer structure composed of a thin metal film with a reduced film thickness and a transparent conductive film (e.g., ITO, indium oxide containing 2 wt% to 20 wt% zinc oxide, indium tin oxide containing silicon, zinc oxide (ZnO), etc.) as the second electrode 617.

[0270] Furthermore, a light-emitting element 618 is formed of a first electrode 613, an EL layer 616, and a second electrode 617. The light-emitting element 618 preferably has the structure described in Embodiment 1 or 2. Furthermore, the pixel portion includes a plurality of light-emitting elements, and the light-emitting device of this embodiment may include both light-emitting elements having the structures described in Embodiment 1 or 2 and light-emitting elements having other structures.

[0271] Furthermore, the sealing substrate 604 and the element substrate 610 are bonded together using 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, which may be filled with a resin, a dry material, or both a resin and a dry material in addition to an inert gas (nitrogen, argon, etc.).

[0272] Epoxy resin or glass powder is preferably used as the sealant 605. These materials are preferably materials that are as impermeable to moisture and oxygen as possible. Furthermore, as a material for the sealing substrate 604, in addition to glass substrates and quartz substrates, plastic substrates made of FRP (Fiber Reinforced Plastics), PVF (Polyvinyl Fluoride), polyester, or acrylic resin can also be used.

[0273] By the above method, a light-emitting device using the light-emitting element described in Embodiment Mode 1 and Embodiment Mode 2 can be obtained.

[0274] <Structural Example 1 of Light Emitting Device>

[0275] exist Figure 5A and Figure 5B , a light-emitting device including a light-emitting element that emits white light and a colored layer (color filter) is shown as an example of a display device.

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

[0277] In addition, 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 to the substrate 1001. In addition, the colored layers and the black layer are covered by a covering layer 1036. Figure 5AIt shows that light does not pass through the colored layer but passes through the external luminescent layer, and light passes through the colored layers of each color and passes through the external luminescent layer. The light that does not pass through the colored layer becomes white light, and the light that passes through the colored layer becomes red light, blue light, and green light, so that an image can be presented with pixels of four colors.

[0278] Figure 5B 1034B) is 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] In addition, although the light-emitting device described above has a structure in which light is emitted from the substrate 1001 side where the TFT is formed (bottom emission type), a light-emitting device may also have a structure in which light is emitted from the sealing substrate 1031 side (top emission type).

[0280] <Structural Example 2 of Light Emitting Device>

[0281] Figure 6 A cross-sectional view of a top-emitting light-emitting device is shown. In this case, a substrate that does not transmit light can be used as substrate 1001. The steps up to the formation of the connection electrode connecting the TFT and the anode of the light-emitting element are carried out in the same manner as for a bottom-emitting light-emitting device. A third interlayer insulating film 1037 is then formed to cover the electrode 1022. This third interlayer insulating film 1037 may also have a planarizing function. The third interlayer insulating film 1037 can be formed using the same material as the second interlayer insulating film 1021 or various other materials.

[0282] Although the lower electrodes 1025W, 1025R, 1025G, and 1025B of the light emitting element are all anodes here, they can also be cathodes. Figure 6 In the top-emission light-emitting device shown, the lower electrodes 1025W, 1025R, 1025G, and 1025B are preferably reflective electrodes. Furthermore, the second electrode 1029 preferably has both light-emitting and light-transmitting functions. Furthermore, a microcavity structure is preferably employed between the second electrode 1029 and the lower electrodes 1025W, 1025R, 1025G, and 1025B to amplify light of a specific wavelength. The structure of the EL layer 1028 is similar to that described in Embodiment Mode 2, and employs an element structure capable of producing white light emission.

[0283] exist Figure 5A 、 Figure 5B and Figure 6In the embodiment of the present invention, a structure of an EL layer capable of obtaining white light emission can be realized by using multiple light-emitting layers or multiple light-emitting units. Note that the structure for obtaining white light emission is not limited to this.

[0284] In adopting Figure 6 In the case of the top emission structure shown, sealing can be performed using a sealing substrate 1031 provided with colored layers (red colored layer 1034R, green colored layer 1034G, blue colored layer 1034B). A black layer (black matrix) 1035 can be provided between pixels on the sealing substrate 1031. The colored layers (red colored layer 1034R, green colored layer 1034G, blue colored layer 1034B) and the black layer (black matrix) can also be covered with a cover layer. A light-transmitting substrate is used as the sealing substrate 1031.

[0285] In addition, although the example of full-color display using four colors of red, green, blue, and white is shown here, the present invention is not limited to this, and full-color display can also be performed using three colors of red, green, and blue. In addition, full-color display can also be performed using four colors of red, green, blue, and yellow.

[0286] By the above method, a light-emitting device using the light-emitting element described in Embodiment Mode 1 and Embodiment Mode 2 can be obtained.

[0287] In addition, this embodiment mode can be combined with other embodiment modes as appropriate.

[0288] Implementation 4

[0289] This embodiment describes a specific example of a display device using the light-emitting element described in Embodiments 1 and 2. The display device described below includes both a reflective liquid crystal element and a light-emitting element and is capable of displaying in both a transmissive mode and a reflective mode. The light-emitting element described in Embodiments 1 and 2 is preferably used as the light-emitting element.

[0290] <Structural Example 1 of Display Device>

[0291] Figure 7A is a block diagram illustrating an example of the structure of a display device 400. Display device 400 includes a plurality of pixels 410 arranged in a matrix in a display portion 362. Display device 400 also includes a circuit GD and a circuit SD. Furthermore, display device 400 includes a plurality of wirings G1, G2, ANO, and CSCOM electrically connected to the plurality of pixels 410 and circuit GD arranged in a direction R. Furthermore, display device 400 includes a plurality of wirings S1 and S2 electrically connected to the plurality of pixels 410 and circuit SD arranged in a direction C.

[0292] 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 have a portion overlapping each other.

[0293] Figure 7B1 1 shows an example of the structure of the electrode 311b included in the pixel 410. The electrode 311b functions as a reflective electrode of the liquid crystal element in the pixel 410. An opening 451 is formed in the electrode 311b.

[0294] exist Figure 7B1 In FIG. 3 , 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, light emitted by the light emitting element 360 passes through the opening 451 and is emitted to the display surface side.

[0295] exist Figure 7B1 , the pixels 410 adjacent to each other in the direction R are pixels corresponding to different colors. Figure 7B1 As shown, it is preferred that the openings 451 in two adjacent pixels in the direction R be provided at different positions on the electrode 311b, rather than being arranged in a single column. This allows the two light-emitting elements 360 to be arranged separately, thereby suppressing the phenomenon (also known as crosstalk) of light emitted by the light-emitting elements 360 entering the colored layer included in the adjacent pixel 410. Furthermore, since the two adjacent light-emitting elements 360 can be arranged separately, a high-resolution display device can be achieved even if the EL layers of the light-emitting elements 360 are manufactured separately using a shadow mask or the like.

[0296] Alternatively, you can use Figure 7B2 Arrangement shown.

[0297] If the ratio of the total area of the openings 451 to the total area of the non-openings is too large, the display using the liquid crystal element will become dark. If the ratio of the total area of the openings 451 to the total area of the non-openings is too small, the display using the light-emitting element 360 will become dark.

[0298] In addition, when the area of the opening 451 provided in the electrode 311 b serving as a reflective electrode is too small, the extraction efficiency of light emitted from the light emitting element 360 becomes low.

[0299] The shape of the opening 451 can be, for example, a polygon, a quadrilateral, an ellipse, a circle, or a cross. Alternatively, it can be a long, narrow strip, a slit, or a grid. Furthermore, the opening 451 can be arranged close to adjacent pixels. Preferably, the opening 451 is arranged close to other pixels displaying the same color. This can suppress crosstalk.

[0300] [Circuit Structure Example]

[0301] Figure 8 is a circuit diagram showing a structural example of the pixel 410 . Figure 8 Two adjacent pixels 410 are shown.

[0302] The pixel 410 includes a switch SW1, a capacitor C1, a liquid crystal element 340, a switch SW2, a transistor M, a capacitor C2, and a light emitting element 360. In addition, the wiring G1, the wiring G2, the wiring ANO, the wiring CSCOM, the wiring S1, and the wiring S2 are electrically connected to the pixel 410. Figure 8 The wiring VCOM1 electrically connected to the liquid crystal element 340 and the wiring VCOM2 electrically connected to the light emitting element 360 are shown.

[0303] Figure 8 An example is shown in which transistors are used for the switch SW1 and the switch SW2.

[0304] In switch SW1, the gate is connected to wiring G1, one of the source and drain is connected to wiring S1, and the other of the source and drain is connected to one electrode of capacitor C1 and one electrode of liquid crystal element 340. The other electrode of capacitor C1 is connected to wiring CSCOM. The other electrode of liquid crystal element 340 is connected to wiring VCOM1.

[0305] In switch SW2, the gate is connected to wiring G2, one of the source and drain is connected to wiring S2, and the other of the source and drain is connected to one electrode of capacitor C2 and the gate of transistor M. In capacitor C2, the other electrode is connected to one of the source and drain of transistor M and wiring ANO. In transistor M, the other of the source and drain is connected to one electrode of light-emitting element 360. In light-emitting element 360, the other electrode is connected to wiring VCOM2.

[0306] Figure 8 The example in which the transistor M includes two gates connected to each other with a semiconductor sandwiched therebetween is shown. This can increase the amount of current that can flow through the transistor M.

[0307] Wiring G1 can be supplied with a signal for controlling switch SW1 to be conductive or non-conductive. Wiring VCOM1 can be supplied with a predetermined potential. Wiring S1 can be supplied with a signal for controlling the alignment of liquid crystal in liquid crystal element 340. Wiring CSCOM can be supplied with a predetermined potential.

[0308] Wiring G2 can be supplied with a signal for controlling switch SW2 to be conductive or non-conductive. Wiring VCOM2 and wiring ANO can each be supplied with a potential that generates a potential difference for causing light-emitting element 360 to emit light. Wiring S2 can be supplied with a signal for controlling the conductive state of transistor M.

[0309] Figure 8 For example, when displaying in the reflective mode, the pixel 410 shown can be driven by signals supplied to the wiring G1 and the wiring S1, and display can be performed by optical modulation of the liquid crystal element 340. Alternatively, when displaying in the transmissive mode, the pixel 410 can be driven by signals supplied to the wiring G2 and the wiring S2, and display can be performed by emitting light from the light-emitting element 360. Furthermore, when driving in both modes, the pixel 410 can be driven by signals supplied to the wiring G1, the wiring G2, the wiring S1, and the wiring S2, respectively.

[0310] Note that although Figure 8 An example is shown in which one pixel 410 includes one liquid crystal element 340 and one light-emitting element 360 , but the present invention is not limited thereto. Figure 9A 4 shows an example in which one pixel 410 includes one liquid crystal element 340 and four light-emitting elements 360 (light-emitting elements 360r, 360g, 360b, and 360w). Figure 8 different, Figure 9A The illustrated pixel 410 can perform full color display using one pixel.

[0311] exist Figure 9A In addition to Figure 8 In addition to the structural example, wiring G3 and wiring S3 are connected to pixel 410.

[0312] exist Figure 9A In the example shown, for example, the four light-emitting elements 360 can each emit red (R), green (G), blue (B), and white (W). Furthermore, a reflective liquid crystal element that emits white can be used as the liquid crystal element 340. This allows for high-reflectivity white display when displaying in reflective mode. Furthermore, when displaying in transmissive mode, high color rendering can be achieved with low power consumption.

[0313] in addition, Figure 9B The following shows an example structure of a pixel 410. Pixel 410 includes a light-emitting element 360w overlapping an opening included in electrode 311, and light-emitting elements 360r, 360g, and 360b arranged around electrode 311. Light-emitting elements 360r, 360g, and 360b preferably have substantially the same light-emitting area.

[0314] <Structural Example 2 of Display Device>

[0315] Figure 10 FIG2 is a perspective view of a display device 300 according to one embodiment of the present invention. The display device 300 has a structure in which a substrate 351 and a substrate 361 are bonded together. Figure 10In FIG, the substrate 361 is indicated by a dotted line.

[0316] The display device 300 includes a display portion 362 , a circuit portion 364 , wiring 365 , a circuit portion 366 , a wiring 367 , and the like. Over the substrate 351 , for example, the circuit portion 364 , wiring 365 , a circuit portion 366 , a wiring 367 , and an electrode 311 b serving as a pixel electrode are provided. Figure 10 An example is shown in which IC373, FPC372, IC375 and FPC374 are mounted on substrate 351. Figure 10 The structure shown is referred to as a display module including a display device 300 , an IC 373 , an FPC 372 , an IC 375 , and an FPC 374 .

[0317] As the circuit portion 364 , for example, a circuit used as a scan line driver circuit can be used.

[0318] The wiring 365 has a function of supplying signals or power to the display portion and the circuit portion 364. The signals or power are input to the wiring 365 from the outside via the FPC 372 or the IC 373.

[0319] in addition, Figure 10 The following illustrates an example of IC 373 being provided on substrate 351 using a COG (Chip On Glass) method or the like. IC 373 can be, for example, an IC having a function such as a scan line driver circuit or a signal line driver circuit. Alternatively, IC 373 may not be provided if display device 300 includes a circuit serving as a scan line driver circuit or a signal line driver circuit, or if the circuit serving as a scan line driver circuit or a signal line driver circuit is externally provided and signals for driving display device 300 are input via FPC 372. Alternatively, IC 373 can be mounted on FPC 372 using a COF (Chip On Film) method or the like.

[0320] Figure 10 An enlarged view of a portion of the display portion 362 is shown. 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 reflective electrodes for the liquid crystal element 340 described below.

[0321] In addition, if Figure 10 As shown, the electrode 311b has an opening. In addition, a light emitting element 360 is provided on the side closer to the substrate 351 than the electrode 311b. Light from the light emitting element 360 is emitted to the substrate 361 side through the opening of the electrode 311b.

[0322] Figure 11 Show that Figure 10An example of a cross section of the display device shown when 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 are cut separately.

[0323] Figure 11 The display device shown has a structure in which display panel 700 and display panel 800 are stacked. Display panel 700 includes resin layers 701 and 702. Display panel 800 includes resin layers 201 and 202. Resin layers 702 and 201 are bonded together by adhesive layer 50. Resin layer 701 is bonded to substrate 351 by adhesive layer 51. Resin layer 202 is bonded to substrate 361 by adhesive layer 52.

[0324] [Display panel 700]

[0325] 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.

[0326] The circuit portion 364 includes a transistor 401 . The display portion 362 includes a transistor 402 and a transistor 403 .

[0327] Each transistor includes a gate, an insulating layer 411, a semiconductor layer, a source, and a drain. The gate and the semiconductor layer overlap with each other via the insulating layer 411. A portion of the insulating layer 411 functions as a gate insulating layer, while another portion functions as a dielectric for the capacitor 405. The conductive layer that serves as the source or drain of the transistor 402 also serves as one electrode of the capacitor 405.

[0328] Figure 11 A transistor with a bottom-gate structure is shown. The circuit portion 364 and the display portion 362 may have different transistor structures. The circuit portion 364 and the display portion 362 may each include multiple types of transistors.

[0329] For example, Figure 12 shown Figure 11As in the modified example of FIG. 2 , the elements constituting the transistors 205 and 206 and the connection portion 207 can be formed using a light-transmitting conductor. Light emitted from the light-emitting element 360 can pass through a portion of or the entirety of the transistors 205 and 206 and the connection portion 207. In addition, light that enters from the substrate 361 side and passes through the liquid crystal 312 can be reflected by the conductive layer 193 b. In order to improve the reliability of the transistors 205 and 206, a non-light-transmitting material such as a metal can be used for one or both of the conductive layer serving as the gate electrode and the conductive layer serving as the back gate electrode.

[0330] exist Figure 11 In the embodiment, 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 process as the gate of the transistor and a conductive layer formed using the same material and process as the source and drain of the transistor.

[0331] Insulating layer 412, insulating layer 413, and insulating layer 414 each cover transistors, etc. There is no particular limit on the number of insulating layers covering transistors, etc. Insulating layer 414 functions as a planarizing layer. Preferably, at least one of insulating layer 412, insulating layer 413, and insulating layer 414 is made of a material that is not susceptible to diffusion of impurities such as water or hydrogen. This effectively prevents impurities from diffusing into the transistors, thereby improving the reliability of the display device.

[0332] 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 lead to degradation of the display device. Figure 11 As shown, the insulating layer 414 is preferably not located at the end of the display device. Figure 11 In the structure, since the insulating layer using the organic compound is not located at the end portion of the display device, entry of impurities into the light-emitting element 360 can be suppressed.

[0333] The light-emitting element 360 includes an electrode 421, an EL layer 422, and an electrode 423. The light-emitting element 360 may also include an optical adjustment layer 424. The light-emitting element 360 has a top emission structure in which light is emitted toward the coloring layer 425 side.

[0334] By arranging transistors, capacitors, wiring, 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.

[0335] One of the electrode 421 and the electrode 423 functions as an anode, and the other functions 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 recombine in the EL layer 422, causing the light-emitting substance contained in the EL layer 422 to emit light.

[0336] Electrode 421 is electrically connected to the source or drain of transistor 403. These components can be directly connected or connected to each other through other conductive layers. Electrode 421 serves as a pixel electrode and is provided in each light-emitting element 360. Two adjacent electrodes 421 are electrically insulated by insulating layer 415.

[0337] The electrode 423 serves as a common electrode and is arranged across the plurality of light emitting elements 360. A constant potential is supplied to the electrode 423.

[0338] 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. Figure 11 Although the case where there is a gap between the electrode 423 and the light shielding layer 426 is shown, they may be in contact with each other. Figure 11 Although the structure in which the spacer 416 is provided on the substrate 351 side is shown, the spacer 416 may be provided on the substrate 361 side (for example, on a side closer to the substrate 361 than the light shielding layer 426 ).

[0339] By combining a color filter (colored layer 425) with 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.

[0340] The colored layer 425 is a colored layer that transmits light in a specific wavelength range. For example, a color filter that transmits light in a red, green, blue, or yellow wavelength range can be used.

[0341] Furthermore, one 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, or the like may be employed.

[0342] Light-shielding layer 426 is provided between adjacent colored layers 425. Light-shielding layer 426 blocks light emitted by adjacent light-emitting elements 360, thereby suppressing color mixing between adjacent light-emitting elements 360. Here, by arranging colored layer 425 so that its end overlaps with light-shielding layer 426, light leakage can be suppressed. Light-shielding layer 426 can be made of a material that blocks light emitted by light-emitting element 360. Furthermore, by arranging light-shielding layer 426 in an area outside of display portion 362, such as circuit portion 364, unintentional light leakage due to waveguide light, etc., can be suppressed, which is preferable.

[0343] 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. Highly moisture-resistant films are preferably used for the insulating layers 476 and 478. Placing the light-emitting element 360, transistors, and the like between a pair of highly moisture-resistant insulating layers is preferred because the intrusion of impurities such as water into these elements can be suppressed, thereby improving the reliability of the display device.

[0344] Examples of highly moisture-resistant insulating films include films containing nitrogen and silicon, such as silicon nitride films and silicon oxynitride films, and films containing nitrogen and aluminum, such as aluminum nitride films. Silicon oxide films, silicon oxynitride films, and aluminum oxide films may also be used.

[0345] 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 below.

[0346] Connecting portion 406 includes wiring 365. Wiring 365 can be formed using the same material and process as the source and drain of the transistor. Connecting portion 406 is electrically connected to an external input terminal that transmits an external signal or potential to circuit portion 364. Here, an example of using FPC 372 as an external input terminal is shown. FPC 372 and connecting portion 406 are electrically connected via a connecting layer 419.

[0347] As the connection layer 419 , various anisotropic conductive films (ACF: Anisotropic Conductive Film) and anisotropic conductive paste (ACP: Anisotropic Conductive Paste) can be used.

[0348] The above is the description of the display panel 700 .

[0349] [Display panel 800]

[0350] The display panel 800 is a reflective liquid crystal display device that adopts a vertical electric field method.

[0351] 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.

[0352] The resin layer 201 and the resin layer 202 are bonded together via 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 surface of the substrate 361.

[0353] Liquid crystal element 529 includes electrode 311b, electrode 562, and liquid crystal 563. Electrode 311b serves as a pixel electrode. Electrode 562 serves as a common electrode. The orientation of liquid crystal 563 can be controlled by utilizing the electric field generated between electrode 311b and electrode 562. An alignment film 564a is provided between liquid crystal 563 and electrode 311b. An alignment film 564b is provided between liquid crystal 563 and electrode 562.

[0354] An insulating layer 576 , an electrode 562 , an alignment film 564 b , and the like are provided over the resin layer 202 .

[0355] 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 .

[0356] 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 .

[0357] Here, a conductive layer that is not electrically connected to the electrode 311b in the source and drain of the transistor 503 can also serve as part of a signal line. Alternatively, a conductive layer serving as the gate of the transistor 503 can also serve as part of a scan line.

[0358] exist Figure 11 , a structural example in which a transistor 501 is provided as an example of the circuit portion 366 is shown.

[0359] 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 unlikely to diffuse.

[0360] An electrode 311b is provided over the insulating layer 514. The electrode 311b is electrically connected to one of the source and drain of the transistor 503 through an opening formed in the insulating layer 514, the insulating layer 513, the insulating layer 512, and the like. The electrode 311b is also electrically connected to one electrode of the capacitor 505.

[0361] 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 .

[0362] 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, examples include 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, and zinc oxide containing gallium. Furthermore, a film containing graphene can also be used. A film containing graphene can be formed, for example, by reducing a film containing graphene oxide.

[0363] 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 alloys of aluminum and titanium, alloys of aluminum and nickel, alloys of aluminum and neodymium, alloys of aluminum, nickel and lanthanum (Al-Ni-La), alloys of silver and copper, alloys of silver, palladium and copper (Ag-Pd-Cu, also referred to as APC) or alloys of silver and magnesium can also be used.

[0364] Here, as the polarizer 599, a linear polarizer or a circular polarizer can be used. As the circular polarizer, for example, a polarizer formed by laminating a linear polarizer and a quarter-wave phase difference plate can be used. This can suppress the reflection of external light. In addition, the desired contrast can be 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 polarizer 599.

[0365] 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.

[0366] 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 metal materials, 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. In addition, 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 Figure 11 By having this shape, the contact area between the connector 543 and the conductive layer electrically connected to the connector can be increased, thereby reducing contact resistance and suppressing problems such as poor contact.

[0367] The connector 543 is preferably disposed so as to be covered by the adhesive layer 517. For example, the connector 543 may be pre-dispersed in the adhesive layer 517 before being cured.

[0368] A connection portion 506 is provided in a region near an end portion of the resin layer 201 . The connection portion 506 is electrically connected to the FPC 374 via a connection layer 519 .

[0369] The above is the description of the display panel 800 .

[0370] [Display components]

[0371] As the 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 the display element included in the first pixel, a reflective liquid crystal element can typically be used. Alternatively, as the display element included in the first pixel, not only a shutter-type MEMS (Micro Electro Mechanical System) element or 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.

[0372] In addition, as a display element included in the second pixel located on the side opposite to the display surface, an element that includes a light source and uses the light from the light source to perform display can be used. Since the brightness and chromaticity of the light emitted by such a pixel are not affected by external light, such a pixel can perform a display with high color reproducibility (wide color gamut) and high contrast, that is, a vivid display can be performed. As the display element included in the second pixel, for example, self-luminous light-emitting elements such as OLED (Organic Light Emitting Diode), LED (Light Emitting Diode), and QLED (Quantum-dot Light Emitting Diode) can be used. Alternatively, as the display element included in the second pixel, a backlight source as a light source and a transmissive liquid crystal element that controls the transmittance of light from the backlight source can be combined for use.

[0373] [Liquid crystal element]

[0374] As the liquid crystal element, an element using the VA (Vertical Alignment) mode can be used. As the vertical alignment mode, an MVA (Multi-Domain Vertical Alignment) mode, a PVA (Patterned Vertical Alignment) mode, an ASV (Advanced SuperView) mode, etc. can be used.

[0375] Liquid crystal elements using various modes can be used. For example, in addition to the VA mode, liquid crystal elements using the TN (Twisted Nematic) mode, IPS (In-Plane-Switching) mode, FFS (Fringe Field Switching) mode, ASM (Axially Symmetric Aligned Micro-cell) mode, OCB (Optically Compensated Birefringence) mode, FLC (Ferroelectric Liquid Crystal) mode, and AFLC (Anti-Ferroelectric Liquid Crystal) mode can be used.

[0376] Liquid crystal elements are elements that control the transmission or non-transmission of light by utilizing the optical modulation effect of liquid crystals. The optical modulation effect of liquid crystals is controlled by the electric field (including transverse electric field, longitudinal electric field, or tilt electric field) applied to the liquid crystals. Liquid crystals used in liquid crystal elements can be thermotropic liquid crystals, low molecular liquid crystals, high molecular liquid crystals, polymer dispersed liquid crystals (PDLC: Polymer Dispersed Liquid Crystal), ferroelectric liquid crystals, antiferroelectric liquid crystals, guest-host liquid crystals, etc. These liquid crystal materials exhibit cholesteric phase, smectic phase, cubic phase, chiral nematic phase, isotropic phase, etc. depending on the conditions.

[0377] In addition, 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 applied mode or design.

[0378] In addition, an orientation film can be provided to control the orientation of the liquid crystal. When a transverse electric field method is used, liquid crystals exhibiting a blue phase can also be used without an orientation film. The blue phase is a type of liquid crystal phase, and 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. Because the blue phase only appears within a narrow temperature range, a liquid crystal composition containing a chiral agent of several 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 low viewing angle dependence. In addition, since an orientation film is not required, a friction treatment is not required, thereby preventing electrostatic damage caused by the friction treatment and reducing defects and damage to the liquid crystal display device during the manufacturing process.

[0379] When a reflective liquid crystal cell is used, a polarizing plate is placed on the display surface side. In addition, it is preferable to place a light diffusion plate on the display surface side because visibility can be improved.

[0380] [Light-emitting element]

[0381] The light-emitting element can be any element capable of self-luminescence, and includes elements whose brightness is controlled by current or voltage. For example, LEDs, QLEDs, organic EL elements, and inorganic EL elements can be used, and the light-emitting elements described in Embodiments 1 and 2 are preferably used.

[0382] In this embodiment, a top-emitting light-emitting element is particularly preferred as the light-emitting element. A conductive film that transmits visible light is used as the electrode on the light-extracting side. Alternatively, a conductive film that reflects visible light is preferably used as the electrode on the side that does not extract light. Furthermore, the light-emitting element may be a single element consisting of a single EL layer or a tandem element comprising multiple EL layers stacked with a charge generation layer interposed therebetween.

[0383] The EL layer includes at least a light-emitting layer. In addition to the light-emitting layer, the EL layer may further include a layer containing a substance with high hole-injecting properties, a substance with high hole-transporting properties, a hole-blocking material, a substance with high electron-transporting properties, a substance with high electron-injecting properties, or a bipolar substance (a substance with high electron-transporting properties and hole-transporting properties).

[0384] The EL layer can use the low molecular weight compounds, high molecular weight compounds, and inorganic compounds listed in Embodiment 1. The layers constituting the EL layer can be formed by methods such as vapor deposition (including vacuum vapor deposition), transfer, printing, inkjet, and coating.

[0385] [Adhesive layer]

[0386] As the adhesive layer, various curing adhesives such as light-curing adhesives such as ultraviolet curing adhesives, reaction-curing adhesives, heat-curing adhesives, and anaerobic adhesives can be used. Examples of these adhesives include epoxy resins, acrylic resins, silicone resins, phenolic resins, polyimide resins, imide resins, PVC (polyvinyl chloride) resins, PVB (polyvinyl butyral) resins, and EVA (ethylene-vinyl acetate) resins. In particular, materials with low moisture permeability such as epoxy resins are preferably used. Alternatively, two-liquid mixed resins can be used. Alternatively, adhesive sheets can be used.

[0387] Furthermore, the resin may also contain a desiccant. For example, a substance that absorbs water by chemical adsorption, such as an alkaline earth metal oxide (calcium oxide or barium oxide, etc.), may be used. Alternatively, a substance that absorbs water by physical adsorption, such as zeolite or silica gel, may be used. Including a desiccant in the resin is preferred because it can inhibit the entry of impurities such as water into the components, thereby improving the reliability of the display panel.

[0388] Furthermore, light extraction efficiency can be improved by mixing a filler or light scattering member having a high refractive index into the above resin. For example, titanium oxide, barium oxide, zeolite, zirconium, etc. can be used.

[0389] [Connection layer]

[0390] As the connection layer, an anisotropic conductive film (ACF), anisotropic conductive paste (ACP), or the like can be used.

[0391] [Coloring Layer]

[0392] Examples of materials that can be used for the colored layer include metal materials, resin materials, and resin materials containing pigments or dyes.

[0393] [Light-shielding layer]

[0394] As materials that can be used for the light-shielding layer, carbon black, titanium black, metals, metal oxides, or 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 containing a film of a material containing a coloring layer can also be used for the light-shielding layer. For example, a laminated structure can be used in which a film containing a material for a coloring layer that allows light of a certain color to pass through and a film containing a material for a coloring layer that allows light of another color to pass through can be used. By making the coloring layer and the light-shielding layer of the same material, in addition to being able to use the same equipment, the process can also be simplified, which is preferred.

[0395] As described above, the structure described in this embodiment can be implemented in combination with the structures described in other embodiment modes as appropriate.

[0396] Implementation 5

[0397] This embodiment describes an electronic device partially including the light-emitting element described in Embodiments 1 and 2. The light-emitting element described in Embodiments 1 and 2 includes a light-emitting element containing a compound according to one embodiment of the present invention. Therefore, the light-emitting element has low driving voltage, high luminous efficiency, 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.

[0398] <Notes on electronic devices>

[0399] Figures 13A to 13G9001, a speaker 9003, operation keys 9005 (including a power switch or an operation switch), connection terminals 9006, sensors 9007 (capable of measuring force, displacement, position, velocity, acceleration, angular velocity, rotational speed, distance, light, liquid, magnetism, temperature, chemical substances, sound, time, hardness, electric field, current, voltage, power, radiation, flow rate, humidity, inclination, vibration, odor, or infrared rays), microphone 9008, and the like. Sensor 9007 may also have a function of measuring biometric information, such as a pulse sensor or fingerprint sensor.

[0400] Figures 13A to 13G The electronic device shown can have various functions. For example, it can have the following functions: the function of displaying various information (static images, dynamic images, text images, etc.) on the display unit; the function of a touch sensor; the function of displaying a calendar, date, or time, etc.; the function of controlling processing by using various software (programs); the function of wireless communication; the function of connecting to various computer networks by using wireless communication functions; the function of sending or receiving various data by using wireless communication functions; the function of reading programs or data stored in a storage medium and displaying them on the display unit; etc. Note that Figures 13A to 13G The functions that the electronic device shown in the figure may have are not limited to the above functions, but may have various functions. Figures 13A to 13G Although not shown in the figure, the electronic device may include multiple display units. In addition, the electronic device may be provided with a camera or the like to enable the electronic device to have the following functions: a function of capturing still images; a function of capturing moving images; a function of storing the captured images in a storage medium (an external storage medium or a storage medium built into the camera); a function of displaying the captured images on a display unit; etc.

[0401] Below, we will explain in detail Figures 13A to 13G Electronic devices shown.

[0402] Figure 13A This is a perspective view of a portable information terminal 9100. The display portion 9001 included in the portable information terminal 9100 is flexible. Therefore, the display portion 9001 can be assembled along the curved surface of the curved housing 9000. Furthermore, the display portion 9001 includes a touch sensor, allowing operation by touching the screen with a finger or a stylus. For example, by touching an icon displayed on the display portion 9001, an application can be launched.

[0403] Figure 13BThis is a perspective view showing a portable information terminal 9101. The portable information terminal 9101 has one or more functions of, for example, a telephone, an electronic notebook, and an information reader. Specifically, it can be used as a smartphone. Note that the speaker 9003, the connection terminal 9006, the sensor 9007, etc. are not shown in the portable information terminal 9101, but can be provided in a manner similar to the embodiment of the present invention. Figure 13A The portable information terminal 9101 is located at the same position as that of the portable information terminal 9100 shown. In addition, the portable information terminal 9101 can display text or image information on multiple surfaces thereof. For example, three operation buttons 9050 (also referred to as operation icons or simply icons) can be displayed on one surface of the display unit 9001. In addition, information 9051 represented by a dotted rectangle can be displayed on another surface of the display unit 9001. In addition, as an example of information 9051, a display indicating that a message from an email, SNS (Social Networking Services), or phone call has been received can be cited; the title of the email or SNS; the name of the sender of the email or SNS; the date; the time; the remaining battery level; and the strength of the received signal such as radio waves can be given. Alternatively, the operation buttons 9050 can be displayed in the position where the information 9051 is displayed instead of the information 9051.

[0404] As the material of the frame 9000, for example, alloys, plastics, ceramics, etc. can be used. As plastic, reinforced plastic can also be used. Carbon fiber reinforced plastics (CFRP), which is a type of reinforced plastic, has the advantages of being lightweight and non-corrosive. In addition, as other reinforced plastics, reinforced plastics using glass fibers and reinforced plastics using aramid fibers can be cited. As alloys, aluminum alloys or magnesium alloys can be cited. Among them, amorphous alloys (also called metallic glass) containing zirconium, copper, nickel, and titanium are excellent in terms of elastic strength. The amorphous alloy is an amorphous alloy having a glass transition region at room temperature, also called a bulk-solidifying amorphous alloy, and is essentially an alloy having an amorphous atomic structure. By utilizing a solidification casting method, the alloy material is cast into a mold of at least a portion of the frame and solidified, and a portion of the frame is formed using a bulk-solidifying amorphous alloy. In addition to zirconium, copper, nickel, and titanium, amorphous alloys may also contain beryllium, silicon, niobium, boron, gallium, molybdenum, tungsten, manganese, iron, cobalt, yttrium, vanadium, phosphorus, carbon, and the like. In addition, the method for forming an amorphous alloy is not limited to the solidification casting method, and vacuum evaporation, sputtering, electroplating, electroless plating, and the like may also be used. In addition, as long as the amorphous alloy maintains a state without long-range order (periodic structure) as a whole, it may contain microcrystals or nanocrystals. Note that alloys include both complete solid solution alloys having a single solid phase structure and partial solutions having two or more phases. By using an amorphous alloy to form the frame 9000, a frame with high elasticity can be achieved. Therefore, if the frame 9000 is an amorphous alloy, even if the portable information terminal 9101 falls and is temporarily deformed at the moment of impact, it can be restored to its original shape, so the impact resistance of the portable information terminal 9101 can be improved.

[0405] Figure 13C 9001. The portable information terminal 9102 has a function of displaying information on three or more surfaces of the display unit 9001. Here, an example is shown in which information 9052, information 9053, and information 9054 are displayed on different surfaces. For example, the user of the portable information terminal 9102 can confirm its display (here, information 9053) while placing the portable information terminal 9102 in a jacket pocket. Specifically, the phone number or name of the caller is displayed in a position where such information can be viewed from above the portable information terminal 9102. The user can confirm this display without having to remove the portable information terminal 9102 from their pocket, thereby being able to decide whether to answer the call.

[0406] Figure 13D: is a perspective view showing a watch-type portable information terminal 9200. The portable information terminal 9200 can execute various applications such as mobile phones, e-mails, article reading and editing, music playback, network communications, computer games, etc. In addition, the display surface of the display portion 9001 is curved, and display can be performed on the curved display surface. In addition, the portable information terminal 9200 can perform short-range wireless communications that are standardized by communications. For example, by communicating with a headset that can perform wireless communications, a hands-free call can be made. In addition, the portable information terminal 9200 includes a connection terminal 9006, which can directly exchange data with other information terminals through a connector. In addition, charging can also be performed through the connection terminal 9006. In addition, the charging operation can also be performed using wireless power supply instead of through the connection terminal 9006.

[0407] Figures 13E to 13G 1 is a perspective view showing a foldable portable information terminal 9201. Figure 13E is a perspective view of the portable information terminal 9201 in the unfolded state, Figure 13F is a perspective view of the portable information terminal 9201 in the middle of changing from one of the unfolded state and the folded state to the other state, Figure 13G This is a perspective view of a portable information terminal 9201 in a folded state. The portable information terminal 9201 offers excellent portability in the folded state, while in the unfolded state, its display is easily viewable due to its large, seamless display area. The display portion 9001 included in the portable information terminal 9201 is supported by three frames 9000 connected by hinges 9055. By bending the two frames 9000 together using the hinges 9055, the portable information terminal 9201 can be reversibly changed from its unfolded state to its folded state. For example, the portable information terminal 9201 can be bent to a radius of curvature of at least 1 mm and no more than 150 mm.

[0408] Examples of electronic devices include: television devices (also called televisions or television receivers); display screens for computers, etc.; digital cameras; digital imagers; digital photo frames; mobile phones (also called mobile phones or mobile phone devices); goggle-type display devices (helmet displays); portable game consoles; portable information terminals; sound reproduction devices; large-scale game consoles such as pinball machines, etc.

[0409] An electronic device according to one embodiment of the present invention may include a secondary battery, and the secondary battery is preferably charged by contactless power transmission.

[0410] Examples of secondary batteries include lithium ion secondary batteries such as lithium polymer batteries using a gel electrolyte (lithium ion polymer battery), lithium ion batteries, nickel hydrogen batteries, nickel cadmium batteries, organic radical batteries, lead storage batteries, air secondary batteries, nickel zinc batteries, and silver zinc batteries.

[0411] The electronic device of one embodiment of the present invention may also include an antenna. By receiving signals through the antenna, an image or information can be displayed on the display unit. In addition, when the electronic device includes a secondary battery, the antenna can be used for contactless power transmission.

[0412] Figure 14A A camera is shown, which includes a housing 7701, a housing 7702, a display portion 7703, operation keys 7704, a lens 7705, a connector 7706, and the like. Operation keys 7704 and lens 7705 are disposed within housing 7701, and display portion 7703 is disposed within housing 7702. Housing 7701 and housing 7702 are connected by connector 7706, and the angle between housing 7701 and housing 7702 can be changed by connector 7706. The image displayed on display portion 7703 can also be switched according to the angle formed between housing 7701 and housing 7702 by connector 7706.

[0413] Figure 14B The present invention shows a notebook personal computer including a housing 7121, a display portion 7122, a keyboard 7123, a pointing device 7124, and the like. Furthermore, because the display portion 7122 has a very high pixel density and high definition, even though the display portion 7122 is small or medium-sized, it can display 8K images, thereby providing very clear images.

[0414] also, Figure 14C The external appearance of the head-mounted display 7200 is shown.

[0415] The head-mounted display 7200 includes a mounting portion 7201 , a lens 7202 , a main body 7203 , a display portion 7204 , a cable 7205 , and the like. Furthermore, a battery 7206 is built into the mounting portion 7201 .

[0416] Power is supplied from a battery 7206 to the main body 7203 via a cable 7205. The main body 7203 is equipped with a wireless receiver and the like, and can display received image information such as image data on the display portion 7204. Furthermore, by capturing the movement of the user's eyeballs and eyelids with a camera provided in the main body 7203 and calculating the coordinates of the user's viewpoint based on this information, the user's viewpoint can be used as an input method.

[0417] In addition, a plurality of electrodes may be provided at the position of the mounting portion 7201 that is touched by the user. The main body 7203 may also have a function of identifying the user's viewpoint by detecting the current flowing through the electrodes according to the movement of the user's eyeballs. In addition, the main body 7203 may have a function of monitoring the user's pulse by detecting the current flowing through the electrodes. The mounting portion 7201 may have various sensors such as a temperature sensor, a pressure sensor, and an acceleration sensor, and may also have a function of displaying the user's biological information on the display portion 7204. In addition, the main body 7203 may also detect the movement of the user's head, etc., and change the image displayed on the display portion 7204 in synchronization with the movement of the user's head, etc.

[0418] also, Figure 14D 1 shows the appearance of a camera 7300. The camera 7300 includes a housing 7301, a display portion 7302, operation buttons 7303, a shutter button 7304, a coupling portion 7305, and the like. The camera 7300 may also be equipped with a lens 7306.

[0419] The coupling portion 7305 includes electrodes and can be connected to a flash device or the like in addition to the viewfinder 7400 described later.

[0420] Here, the camera 7300 has a structure that allows the lens 7306 to be removed from the housing 7301 and replaced. Alternatively, the lens 7306 and the housing 7301 may be integrally formed.

[0421] Image capture can be performed by pressing the shutter button 7304. Note that the display portion 7302 includes a touch sensor, so that image capture can also be performed by operating the display portion 7302.

[0422] The display device or touch sensor according to one embodiment of the present invention can be applied to the display portion 7302 .

[0423] Figure 14E An example is shown in which a camera 7300 is equipped with a viewfinder 7400 .

[0424] The viewfinder 7400 includes a housing 7401 , a display portion 7402 , a button 7403 , and the like.

[0425] The housing 7401 includes a connection portion that fits with the connection portion 7305 of the camera 7300, allowing the viewfinder 7400 to be attached to the camera 7300. The connection portion also includes electrodes, allowing the display portion 7402 to display images received from the camera 7300 via the electrodes.

[0426] A button 7403 is used as a power button. By using the button 7403, the display portion 7402 can be switched between display and non-display.

[0427] In addition, Figure 14D and Figure 14E In the embodiment, the camera 7300 and the viewfinder 7400 are separate and detachable electronic devices, but a viewfinder having a display device or a touch sensor according to one embodiment of the present invention may be built into the housing 7301 of the camera 7300 .

[0428] Figures 15A to 15E 1 and 2 are diagrams showing the appearance of helmet displays 7500 and 7510.

[0429] The helmet display 7500 includes a housing 7501 , two display units 7502 , operation buttons 7503 , and a belt-shaped fixing tool 7504 .

[0430] The head-mounted display 7500 has two display units in addition to the functions of the head-mounted display 7200 described above.

[0431] By including two display units 7502, the user can observe one display unit with one eye and the other display unit with the other eye. This allows high-resolution images to be displayed even when performing three-dimensional displays utilizing parallax. In addition, the display unit 7502 is curved in an arc shape approximately centered on the user's eyes. This ensures that the user's eyes are equidistant from the display surface of the display unit, allowing the user to see more natural images. Furthermore, since the user's eyes are located in the normal direction to the display surface of the display unit, even if the brightness and chromaticity of the light from the display unit change depending on the viewing angle, the effect is essentially negligible, allowing for the display of more realistic images.

[0432] The operation button 7503 has a function of a power button, etc. In addition, buttons other than the operation button 7503 may be included.

[0433] In addition, the helmet display 7510 includes a housing 7501 , a display portion 7502 , a belt-shaped fixing tool 7504 , and a pair of lenses 7505 .

[0434] The user can see the display on the display portion 7502 through the lens 7505. Preferably, the display portion 7502 is arranged in a curved manner. By arranging the display portion 7502 in a curved manner, the user can experience a high sense of reality.

[0435] The display portion 7502 can employ a display device according to one embodiment of the present invention. Since the display device according to one embodiment of the present invention can improve resolution, even if Figure 15E By using lens 7505 for enlargement, the user cannot perceive the pixels, thereby displaying a more realistic image.

[0436] Figure 16A10 shows an example of a television set. In a television set 9300, a display portion 9001 is incorporated into a housing 9000. Here, a structure in which the housing 9000 is supported by a stand 9301 is shown.

[0437] The operation can be performed by using the operation switch provided by the frame 9000 and the remote control unit 9311 provided separately. Figure 16A The television set 9300 shown in FIG. Alternatively, the display portion 9001 may be provided with a touch sensor so that the display portion 9001 can be operated by touching the display portion 9001 with a finger or the like. Furthermore, the remote controller 9311 may be provided with a display portion for displaying data output from the remote controller 9311. Using the operation keys or touch panel provided on the remote controller 9311, the channel and volume can be controlled, and the image displayed on the display portion 9001 can be manipulated.

[0438] The television set 9300 is configured to include a receiver and a modem. The receiver can receive standard television broadcasts. Furthermore, the modem connects the television set to a wired or wireless communication network, enabling one-way (from a sender to a receiver) or two-way (between a sender and a receiver, or between receivers) information communication.

[0439] Furthermore, since the electronic device or lighting device of one embodiment of the present invention is flexible, it can be assembled along the curved surfaces of the inner or outer walls of houses and buildings, or the interior or exterior decoration of automobiles.

[0440] Figure 16B The exterior appearance of automobile 9700 is shown. Figure 16C The driver's seat of a car 9700 is shown. The car 9700 includes a body 9701, wheels 9702, an instrument panel 9703, a lamp 9704, and the like. A display device or a light-emitting device according to one embodiment of the present invention can be used in a display unit or the like of the car 9700. For example, a display device or a light-emitting device according to one embodiment of the present invention can be provided in Figure 16C Display portions 9710 to 9715 are shown.

[0441] The display portion 9710 and the display portion 9711 are display devices disposed on the windshield of a car. By using a light-transmitting conductive material to manufacture electrodes or wiring in a display device or a light-emitting device, etc., a display device or a light-emitting device according to one embodiment of the present invention can be made into a so-called transparent display device or light-emitting device that allows viewing from the opposite side. The display portion 9710 and the display portion 9711 of the transparent display device do not obstruct the field of vision even when driving the car 9700. Therefore, the display device or the light-emitting device according to one embodiment of the present invention can be disposed on the windshield of the car 9700. In addition, when a transistor or the like is provided in the display device or the light-emitting device for driving the display device or the input / output device, it is preferable to use a light-transmitting transistor such as an organic transistor using an organic semiconductor material or a transistor using an oxide semiconductor.

[0442] Display unit 9712 is a display device provided in the pillar portion. For example, by displaying an image from an imaging unit provided in the vehicle body on display unit 9712, the field of view blocked by the pillar can be supplemented. Display unit 9713 is a display device provided in the instrument panel portion. For example, by displaying an image from an imaging unit provided in the vehicle body on display unit 9713, the field of view blocked by the instrument panel can be supplemented. In other words, by displaying an image from an imaging unit provided on the outside of the vehicle, blind spots can be supplemented, thereby improving safety. In addition, by displaying supplementary images of parts that cannot be seen, safety can be confirmed more naturally and comfortably.

[0443] Figure 16D The interior of a vehicle is shown, using a bench seat as both the driver's and passenger seats. Display unit 9721 is a display device mounted on the vehicle door. For example, by displaying images from an imaging unit mounted on the vehicle body on display unit 9721, it is possible to supplement the field of view obstructed by the vehicle door. Display unit 9722 is a display device mounted on the steering wheel. Display unit 9723 is a display device mounted in the center of the bench seat. Furthermore, by mounting the display device on the seat surface or backrest, for example, it can be used as a seat heater, using the display device as a heat source.

[0444] Display unit 9714, display unit 9715, or display unit 9722 can provide navigation information, a speedometer, a tachometer, distance traveled, fuel level, gear status, air conditioning settings, and other various information. Furthermore, the user can appropriately change the display content and layout displayed on the display unit. Furthermore, display units 9710 to 9713, display unit 9721, and display unit 9723 can also display the aforementioned information. Display units 9710 to 9715, and display units 9721 to 9723 can also function as lighting devices. Furthermore, display units 9710 to 9715, and display units 9721 to 9723 can also function as heating devices.

[0445] The electronic device described in this embodiment includes a display portion for displaying certain information. Note that a light-emitting element according to one embodiment of the present invention can also be applied to an electronic device that does not include a display portion. Furthermore, although this embodiment shows a structure in which the display portion of the electronic device is flexible and can display on a curved display surface or a structure in which the display portion can be folded, the present invention is not limited thereto and a structure in which the display portion is not flexible and displays on a flat surface can also be used.

[0446] The structure described in this embodiment can be used in combination with the structures described in other embodiment modes as appropriate.

[0447] Implementation Method 6

[0448] In this embodiment, referring to Figures 17A to 18 Examples of cases where the light-emitting element of one embodiment of the present invention is applied to various electronic devices and lighting devices will be described.

[0449] By forming the light-emitting element of one embodiment of the present invention on a flexible substrate, an electronic device or a lighting device including a light-emitting region having a curved surface can be realized.

[0450] Furthermore, a light-emitting device to which the light-emitting element of one embodiment of the present invention is applied can also be applied to automobile lighting provided on a windshield, a ceiling, or the like.

[0451] Figure 17A A perspective view showing one side of the multi-function terminal 3500 is shown. Figure 17B This figure shows a perspective view of another side of the multifunction terminal 3500. In the multifunction terminal 3500, a display portion 3504, a camera 3506, a lighting fixture 3508, and the like are incorporated into a housing 3502. The light-emitting element of one embodiment of the present invention can be used for the lighting fixture 3508.

[0452] Illumination 3508, which includes a light-emitting element according to one embodiment of the present invention, functions as a surface light source. Therefore, unlike point light sources such as LEDs, it can produce light with low directivity. For example, when using illumination 3508 in combination with camera 3506, it is possible to simultaneously illuminate or flash illumination 3508 while using camera 3506 to capture images. Because illumination 3508 functions as a surface light source, it is possible to obtain images that appear as if they were taken under natural light.

[0453] Notice, Figure 17A and Figure 17B The multifunctional terminal 3500 shown is Figures 13A to 13G The electronic devices shown may likewise have a variety of functions.

[0454] Furthermore, a speaker, a sensor (the sensor having the function of measuring the following factors: force, displacement, position, speed, acceleration, angular velocity, rotational speed, distance, light, liquid, magnetism, temperature, chemical substances, sound, time, hardness, electric field, current, voltage, electricity, radiation, flow rate, humidity, inclination, vibration, odor, or infrared rays), a microphone, etc. may be provided within the housing 3502. Furthermore, by providing a detection device having a sensor for detecting inclination, such as a gyroscope and an accelerometer, within the multi-function terminal 3500, the orientation (portrait or landscape) of the multi-function terminal 3500 can be determined and the screen display of the display unit 3504 can be automatically switched.

[0455] The display portion 3504 can also be used as an image sensor. For example, by touching the display portion 3504 with a palm or finger, palm prints or fingerprints can be captured, enabling personal identification. Furthermore, by providing a backlight or sensing light source that emits near-infrared light in the display portion 3504, finger veins, palm veins, and the like can also be captured. Note that the light-emitting element of one embodiment of the present invention can be applied to the display portion 3504.

[0456] Figure 17C A perspective view of a security light 3600 is shown. The security light 3600 includes an illumination 3608 outside a housing 3602, and a speaker 3610 and the like are incorporated into the housing 3602. The light-emitting element of one embodiment of the present invention can be used for the illumination 3608.

[0457] Safety light 3600 illuminates when, for example, lighting 3608 is grasped or held. Furthermore, an electronic circuit capable of controlling the lighting pattern of safety light 3600 may be provided within housing 3602. This electronic circuit may, for example, be a circuit capable of emitting light once or intermittently, or a circuit capable of adjusting the amount of light emitted by controlling the current flowing therein. Furthermore, a circuit capable of emitting a loud alarm sound from speaker 3610 simultaneously with the illumination 3608 may be incorporated.

[0458] Since the security light 3600 can emit light in all directions, it can emit light or emit light and sound to frighten criminals, etc. In addition, the security light 3600 can include a camera such as a digital still camera with a camera function.

[0459] Figure 18 This is an example of using a light-emitting element in an indoor lighting device 8501. In addition, since the light-emitting element can be large-area, a large-area lighting device can also be formed. In addition, a lighting device 8502 having a curved light-emitting area can be formed by using a frame having a curved surface. The light-emitting element shown in this embodiment is in the form of a thin film, so the design freedom of the frame is high. Therefore, a lighting device that can correspond to various designs can be formed. In addition, a large lighting device 8503 can also be installed on the wall of the room. Touch sensors can also be provided in the lighting devices 8501, 8502, and 8503 to start or turn off the power.

[0460] Furthermore, by using light-emitting elements on the surface side of a table, a lighting device 8504 having the function of a table can be provided. Furthermore, by using light-emitting elements on a part of other furniture, a lighting device having the function of furniture can be provided.

[0461] As described above, by applying the light-emitting element of one embodiment of the present invention, a lighting device and an electronic device can be obtained. Note that the light-emitting device is not limited to the lighting device and electronic device described in this embodiment, and can be applied to electronic devices in various fields.

[0462] The structure described in this embodiment can be implemented in combination with the structures described in other embodiment modes as appropriate.

[0463] Example 1

[0464] In this embodiment, the synthesis method of N-(biphenyl-4-yl)-N-{4-[6-(biphenyl-4-yl)pyrimidin-4-yl]phenyl}-9,9-dimethyl-9H-fluorene-2-amine (abbreviation: 6BP-4FBiPPm) (structural formula (100)), which is one of the organic compounds according to one embodiment of the present invention, and the physical properties of the compound are described.

[0465] <Synthesis example 1>

[0466] Step 1: Synthesis of N-(biphenyl-4-yl)-N-{4-[6-(biphenyl-4-yl)pyrimidin-4-yl]phenyl}-9,9-dimethyl-9H-fluoren-2-amine (abbreviated as: 6BP-4FBiPPm)

[0467] Into a 200 mL three-necked flask were poured 1.2 g (4.5 mmol) of 4-(4-biphenyl)-6-chloropyrimidine, 2.2 g (4.5 mmol) of 4-[N-(biphenyl-4-yl)-N-(9,9-dimethyl-9H-fluoren-2-yl)amino]phenylboronic acid, 1.9 g (13.5 mmol) of potassium carbonate, and 55 mg (0.18 mmol) of tri(2-methylphenyl)phosphine. To this mixture were added 25 mL of toluene, 10 mL of ethanol, and 7 mL of water. The mixture was stirred and degassed under reduced pressure. To this mixture was added 20 mg (0.090 mmol) of palladium(II) anhydride, and the mixture was stirred at 90°C under a nitrogen stream for 6 hours. After stirring, the aqueous layer of the mixture was extracted with toluene, and the extract and the organic layer were combined and washed with water and saturated brine. The organic layer was dried over magnesium sulfate. The mixture was gravity filtered, and the filtrate was concentrated to obtain a solid. The solid was purified by silica gel column chromatography (developing solvent: toluene, followed by toluene:ethyl acetate 4:1) to obtain a solid. Purification was performed using silica gel (Kanto Chemical Co., Ltd., Japan, catalog number: 37560-84). The resulting solid was recrystallized from toluene / ethanol to obtain 2.7 g of a yellow solid in an 89% yield. The synthesis scheme for Step 1 is shown below in Formula (A-1).

[0468] (A-1)

[0469]

[0470] 2.7 g of the obtained solid was purified by sublimation using a gradient sublimation method. The solution was heated at 305° C. under a pressure of 2.8 Pa and an argon flow rate of 15 mL / min. After sublimation purification, 2.3 g of a yellow solid was obtained at a recovery rate of 88%.

[0471] The nuclear magnetic resonance spectroscopy of the obtained solid is shown below ( 1 1H NMR) analytical data.

[0472] 1 H NMR (DMSO-d6, 300MHz): δ=1.43 (s, 6H), 7.12-7.18 (m, 3H), 7.26 (d, J1=8.7Hz, 2 H), 7.30-7.38(m, 3H), 7.40-7.56(m, 7H), 7.68-7.73(m, 4H), 7.80(dd, J1=7.2Hz , J2=1.5Hz, 3H), 7.85 (d, J1=8.1Hz, 1H), 8.89 (d, J1=8.4Hz, 2H), 8.34 (d, J1=8. 7Hz, 2H), 8.46 (d, J1=8.1Hz, 2H), 8.58 (d, J1=1.5Hz, 1H), 9.24 (d, J1=1.5Hz, 1H)

[0473] in addition, Figure 19A and Figure 19B The obtained solid 1 H NMR spectrum. Figure 19B yes Figure 19A The measurement results show that 6BP-4FBiPPm was obtained.

[0474] <Characteristics of 6BP-4FBiPPm>

[0475] Figure 20 The absorption spectrum and emission spectrum of the toluene solution of 6BP-4FBiPPm are shown. Figure 21 The absorption and emission spectra of the thin film are shown. The solid thin film was formed on a quartz substrate by vacuum evaporation. The absorption spectrum of the toluene solution was measured using an ultraviolet-visible spectrophotometer (V550, manufactured by JASCO Corporation). Figure 20 The absorption spectrum of the toluene solution of 6BP-4FBiPPm shown was obtained by subtracting the absorption spectrum of toluene measured by placing only toluene in a quartz dish from the absorption spectrum of the toluene solution of 6BP-4FBiPPm. In the measurement of the absorption spectrum of the film, a spectrophotometer (spectrophotometer U4100 manufactured by Hitachi High-Technologies Corporation) was used. The emission spectrum was measured using a fluorescence spectrophotometer (FS920 manufactured by Hamamatsu Photonics Co., Ltd., Japan).

[0476] Depend on Figure 20 It can be seen that the absorption peaks of 6BP-4FBiPPm toluene solution are observed near 395nm, 356nm, and 310nm. Figure 20 It can be seen that the peak of the luminescence wavelength is 468nm (excitation wavelength 393nm). Figure 21 It can be seen that the absorption peaks of the 6BP-4FBiPPm film are observed near 402nm, 362nm, 313nm, 265nm, and 204nm. Figure 21 The peak emission wavelength is near 497 nm (excitation wavelength 402 nm), and 6BP-4FBiPPm is confirmed to emit 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 substance in the visible region.

[0477] In addition, the 6BP-4FBiPPm film is not easy to aggregate in the atmosphere, has little morphological change, and has good film quality.

[0478] The HOMO and LUMO levels of 6BP-4FBiPPm were calculated by cyclic voltammetry (CV) measurement. The calculation method is shown below.

[0479] As a measuring device, an electrochemical analyzer (ALS model 600A or 600C manufactured by BAS Inc.) was used. In addition, a solution for CV measurement was prepared as follows: dehydrated dimethylformamide (DMF) (manufactured by Aldrich Co., Ltd., 99.8%, catalog number: 22705-6) was used as a solvent, and tetra-n-butylammonium perchlorate (n-Bu4NClO) was used as a supporting electrolyte. 4) The sample was prepared by dissolving a 100 mmol / L solution of 1% dapoxetine (manufactured by Tokyo Chemical Industry Co., Ltd., catalog number: T0836) and dissolving the sample to be measured at a concentration of 2 mmol / L. A platinum electrode (manufactured by BAS Inc., PTE platinum electrode) was used as the working electrode, a platinum electrode (manufactured by BAS Inc., Pt counter electrode for VC-3 (5 cm)) was used as the auxiliary electrode, and an Ag / Ag electrode was used as the reference electrode. + Electrode (manufactured by BAS Inc., RE7 non-aqueous solvent type reference electrode). In addition, the measurement was carried out at room temperature (above 20°C and below 25°C). The scanning speed during CV measurement was unified to 0.1V / sec, and the oxidation potential Ea[V] and reduction potential Ec[V] relative to the reference electrode were measured. Ea is the intermediate potential between the oxidation-reduction wave, and Ec is the intermediate potential between the reduction-oxidation wave. 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.

[0480] 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.

[0481] The results showed that the HOMO energy level of 6BP-4FBiPPm, measured as the oxidation potential Ea [V], was -5.48 eV, while the LUMO energy level was -2.79 eV. Furthermore, a comparison of the waveforms from the first and 100th repeated measurements of the redox wave revealed that 92% of the peak intensity was retained in the Ea measurement, and 87% of the peak intensity was retained in the Ec measurement, demonstrating that 6BP-4FBiPPm exhibits very high resistance to oxidation and reduction.

[0482] Example 2

[0483] In this embodiment, the synthesis method of 4-[6-(biphenyl-4-yl)pyrimidin-4-yl]-4'-phenyl-4"-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviated as: 6BP-4PCBBiPPm) (structural formula (101)), which is one of the organic compounds according to one embodiment of the present invention, and the physical properties of the compound are described.

[0484] <Synthesis example 2>

[0485] Step 1: Synthesis of 4-[6-(biphenyl-4-yl)pyrimidin-4-yl]-4'-phenyl-4"-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviated as 6BP-4PCBBiPPm)

[0486] Into a 200 mL three-necked flask were placed 1.7 g (5.0 mmol) of 4-(4-biphenyl)-6-(4-chlorophenyl)pyrimidine, 2.7 g (5.5 mmol) of N-biphenyl-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]amine, 1.5 g (15 mmol) of sodium tert-butoxide, and 90 mg (0.25 mmol) of di(1-adamantane)-n-butylphosphine. To this mixture was added 25 mL of toluene and stirred under reduced pressure for degassing. To this mixture was added 29 mg (0.050 mmol) of bis(dibenzylideneacetone)palladium(0), and the mixture was heated and stirred at 110°C under a nitrogen stream for 23.5 hours. After stirring, toluene was added to the mixture and suction filtered through magnesium silicate (Wako Pure Chemical Industries, Ltd., Japan, Catalog No. 540-00135), diatomaceous earth (Wako Pure Chemical Industries, Ltd., Japan, Catalog No. 531-16855), and alumina to obtain a filtrate. The filtrate was concentrated to obtain a solid. The resulting solid was recrystallized from toluene to obtain 3.3 g of a light yellow solid in an 82% yield. The synthesis scheme for Step 1 is shown in Formula (A-2) below.

[0487] (A-2)

[0488]

[0489] 3.2 g of the obtained light yellow solid was purified by sublimation using a gradient sublimation method. The mixture was heated at 380° C. under a pressure of 2.9 Pa and an argon flow rate of 15 mL / min. After sublimation purification, 2.8 g of a yellow solid was obtained at a recovery rate of 88%.

[0490] The nuclear magnetic resonance spectroscopy of the obtained solid is shown below ( 1 1H NMR) analytical data.

[0491] 1H NMR (1,1,2,2-Tetrachloroethane-d2, 300MHz): δ=7.31-7.41(m, 8H), 7.43-7.54(m, 9H), 7.61-7.75(m, 13H), 7.81 (d, J1=8.4Hz, 1H), 8, 11-8.14 (m, 3H), 8, 21-8.28 (m, 3H), 8.39 (d, J1=0.9Hz, 2H), 9.30 (s, 1H)

[0492] in addition, Figure 22A and Figure 22B The obtained solid 1 H NMR spectrum. Figure 22B yes Figure 22A The measurement results show that 6BP-4PCBBiPPm was obtained.

[0493] <Characteristics of 6BP-4PCBBiPPm>

[0494] then, Figure 23 The absorption spectrum and emission spectrum of the toluene solution of 6BP-4PCBBiPPm are shown. Figure 24 The absorption spectrum and emission spectrum of the thin film are shown. The measurement method is the same as that of Example 1 shown above.

[0495] Depend on Figure 23 It can be seen that the absorption peaks of 6BP-4PCBBiPPm toluene solution are observed near 394nm, 347nm, 324nm, 302nm, and 282nm. Figure 23 It can be seen that the peak of the luminescence wavelength is 468nm (excitation wavelength 396nm). Figure 24 It can be seen that the absorption peaks of the 6BP-4PCBBiPPm film are observed near 400nm, 355nm, 332nm, 304nm, 282nm, and 244nm. Figure 24 It is found that the peak emission wavelength is around 512 nm (excitation wavelength 413 nm). The compound of one embodiment of the present invention can be used as a host material for a light-emitting substance or a host material for a fluorescent substance in the visible region.

[0496] In addition, the 6BP-4PCBBiPPm film is not easy to agglomerate in the atmosphere, has little morphological change, and has good film quality.

[0497] Next, the HOMO and LUMO energy levels of 6BP-4PCBBiPPm were calculated using cyclic voltammetry (CV) measurements. The calculation method was the same as in Example 1.

[0498] The results show that the HOMO energy level of 6BP-4PCBBiPPm, measured as the oxidation potential Ea [V], was -5.48 eV, and the LUMO energy level was -2.82 eV. Furthermore, a comparison of the waveforms from the first and 100th measurements of the repeated oxidation-reduction wave revealed that 79% of the peak intensity was retained in the Ea measurement, while 94% of the peak intensity was retained in the Ec measurement. This demonstrates that 6BP-4PCBBiPPm has very high resistance to oxidation and reduction.

[0499] Example 3

[0500] In this embodiment, the synthesis method of N-(biphenyl-4-yl)-N-{3-[6-(biphenyl-4-yl)pyrimidin-4-yl]phenyl}-9,9-dimethyl-9H-fluorene-2-amine (abbreviation: 6BP-4mFBiPPm) (structural formula (102)), which is one of the organic compounds according to one embodiment of the present invention, and the physical properties of the compound are described.

[0501] <Synthesis example 3>

[0502] Step 1: Synthesis of N-(biphenyl-4-yl)-N-{3-[6-(biphenyl-4-yl)pyrimidin-4-yl]phenyl}-9,9-dimethyl-9H-fluoren-2-amine (abbreviated as: 6BP-4mFBiPPm)

[0503] Into a 200 mL three-necked flask were poured 2.1 g (6.0 mmol) of 4-(4-biphenyl)-6-(3-chlorophenyl)pyrimidine, 2.4 g (6.6 mmol) of N-(biphenyl-4-yl)-9,9-dimethyl-9H-fluoren-2-amine, 1.73 g (18.0 mmol) of sodium tert-butoxide, and 107 mg (0.30 mmol) of di(1-adamantane)-n-butylphosphine. 30 mL of toluene was added to the mixture, and the mixture was stirred under reduced pressure for degassing. 34 mg (0.060 mmol) of bis(dibenzylideneacetone)palladium(0) was added to the mixture, and the mixture was heated and stirred at 110°C under a nitrogen stream for 35 hours. After stirring, toluene was added to the mixture, and the mixture was filtered using magnesium silicate, diatomaceous earth, and alumina to obtain a filtrate. The filtrate was concentrated to obtain a solid. The solid was purified by silica gel column chromatography (developing solvent: toluene, followed by toluene:ethyl acetate 100:3) to obtain a solid. The resulting solid was recrystallized from toluene / ethanol to obtain 3.9 g of a pale yellow solid in a 97% yield. The synthesis scheme for Step 1 is shown below in Formula (A-3).

[0504] (A-3)

[0505]

[0506] 3.8 g of the obtained light yellow solid was purified by sublimation using a gradient sublimation method. The mixture was heated at 300° C. under a pressure of 2.7 Pa and an argon flow rate of 15 mL / min. After sublimation purification, 3.2 g of a light yellow solid was obtained at a recovery rate of 84%.

[0507] The nuclear magnetic resonance spectroscopy of the obtained solid is shown below ( 1 1H NMR) analytical data.

[0508] 1 H NMR (DMSO-d6, 300MHz): δ=1.40 (s, 6H), 7.09 (dd, J1=7.8Hz, J2=2.1Hz, 1H), 7.19 (d, J1=8.7Hz, 2H), 7.26-7.58 (m, 12H), 7.66-7.70 (m, 4H), 7.76-7.82 (m, 4H), 7.87 (d, J1 = 8.7Hz, 2H), 8.12 (d, J1 = 7.8Hz, 1H), 8.18 (t, J1 = 2.1Hz, 1H), 8.45 (d, J1=8.4Hz, 2H), 8.64 (d, J1=0.9Hz, 1H), 9.22 (d, J1=0.9Hz, 1H)

[0509] in addition, Figure 25A and Figure 25B The obtained solid 1 H NMR spectrum. Figure 25B yes Figure 25A The measurement results show that 6BP-4mFBiPPm was obtained.

[0510] <Characteristics of 6BP-4mFBiPPm>

[0511] Figure 26 The absorption spectrum and emission spectrum of the toluene solution of 6BP-4mFBiPPm are shown. Figure 27 The absorption and emission spectra of the thin film are shown. The absorption and emission spectra of the solution and the absorption spectrum of the thin film were measured in the same manner as in Example 1. The emission spectrum of the thin film was measured using a microscopic PL device (LabRAM HR-PL manufactured by Horiba, Ltd., Japan).

[0512] Depend on Figure 26 It can be seen that the absorption peaks of 6BP-4mFBiPPm toluene solution are observed near 352nm and 327nm. Figure 26 It can be seen that the peak of the luminescence wavelength is 496nm (excitation wavelength 354nm). Figure 27It can be seen that the absorption peaks of the 6BP-4mFBiPPm film are observed near 365nm, 327nm, 264nm, and 204nm. Figure 27 It is found that the peak emission wavelength is around 496 nm (excitation wavelength 410 nm). The compound of one embodiment of the present invention can be used as a host material for a light-emitting substance or a host material for a fluorescent substance in the visible region.

[0513] In addition, the 6BP-4mFBiPPm film is not easily aggregated in the atmosphere, has little morphological change, and has good film quality.

[0514] Next, the HOMO and LUMO energy levels of 6BP-4mFBiPPm were calculated using cyclic voltammetry (CV) measurements. The calculation method was the same as in Example 1.

[0515] The results show that the HOMO energy level of 6BP-4mFBiPPm, measured as the oxidation potential Ea [V], was -5.46 eV, and the LUMO energy level was -2.83 eV. Furthermore, a comparison of the waveforms from the first and 100th measurements of the repeated oxidation-reduction wave revealed that 91% of the peak intensity was maintained in the Ea measurement, and 90% of the peak intensity was maintained in the Ec measurement, demonstrating that 6BP-4mFBiPPm has very high resistance to oxidation and reduction.

[0516] Example 4

[0517] In this embodiment, the synthesis method of 3-[6-(biphenyl-4-yl)pyrimidin-4-yl]-4'-phenyl-4"-(9-phenyl-9H-carbazole-3-yl)triphenylamine (abbreviated as: 6BP-4mPCBBiPPm) (structural formula (103)), which is one of the organic compounds according to one embodiment of the present invention, and the physical properties of the compound are described.

[0518] <Synthesis example 4>

[0519] Step 1: Synthesis of 3-[6-(biphenyl-4-yl)pyrimidin-4-yl]-4'-phenyl-4"-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviated as: 6BP-4mPCBBiPPm)

[0520] Into a 200 mL three-necked flask were poured 1.7 g (5.0 mmol) of 4-(4-biphenyl)-6-(3-chlorophenyl)pyrimidine, 2.7 g (5.5 mmol) of N-biphenyl-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]amine, 1.45 g (15.1 mmol) of sodium tert-butoxide, and 90 mg (0.25 mmol) of di(1-adamantane)-n-butylphosphine. 25 mL of toluene was added to the mixture, and the mixture was stirred while reducing pressure to degas. 29 mg (0.050 mmol) of bis(dibenzylideneacetone)palladium(0) was added to the mixture, and the mixture was heated and stirred at 110° C. under a nitrogen flow for 35 hours. After stirring, toluene was added to the mixture, and the mixture was filtered using magnesium silicate, diatomaceous earth, and alumina to obtain a filtrate. The filtrate was concentrated to obtain a solid. The solid was purified by silica gel column chromatography (developing solvent: toluene, followed by toluene:ethyl acetate = 100:1) to obtain a solid. The resulting solid was reprecipitated with ethyl acetate / ethanol to obtain 3.3 g of a yellow solid in an 83% yield. The synthesis scheme for Step 1 is shown below in Formula (A-4).

[0521] (A-4)

[0522]

[0523] 3.3 g of the obtained yellow solid was purified by sublimation using a gradient sublimation method. The solution was heated at 370° C. under a pressure of 3.0 Pa and an argon flow rate of 15 mL / min. After sublimation purification, 2.7 g of a yellow solid was obtained at a recovery rate of 83%.

[0524] The nuclear magnetic resonance spectroscopy of the obtained solid is shown below ( 1 1H NMR) analytical data.

[0525] 1 H NMR (DMSO-d6, 300MHz): δ=7.24 (dd, J1=8.7Hz, J2=14.7Hz, 4H), 7.29-7.62 (m, 13H), 7.65-7.82 (m, 13H), 7.88 (d, J1=8.4Hz, 2H), 8. 15 (d, J1=7.8Hz, 1H), 8.19 (s, 1H), 8.35 (d, J1=7.2Hz, 1H), 8.47 (d, J1=8.4Hz, 2H), 8.60 (d, J1=1.5Hz, 1H), 8.66 (s, 1H), 9.25 (s, 1H)

[0526] in addition, Figure 28A and Figure 28B The obtained solid 1 H NMR spectrum. Figure 28B yes Figure 28AThe measurement results show that 6BP-4mPCBBiPPm was obtained.

[0527] <Characteristics of 6BP-4mPCBBiPPm>

[0528] Figure 29 The absorption spectrum and emission spectrum of the toluene solution of 6BP-4mPCBBiPPm are shown. Figure 30 The absorption and emission spectra of the thin film are shown. The absorption and emission spectra of the solution and the absorption spectrum of the thin film were measured using the same method as in Example 1. The emission spectrum of the thin film was measured using a microscopic PL device (Labram HR-PL manufactured by Horiba, Ltd., Japan).

[0529] Depend on Figure 29 It can be seen that the absorption peaks of 6BP-4mPCBBiPPm toluene solution are observed near 392nm and 282nm. Figure 29 It can be seen that the peak of the luminescence wavelength is 498nm (excitation wavelength 332nm). Figure 30 It can be seen that the absorption peaks of 6BP-4mPCBBiPPm film are observed near 363nm, 330nm, 285nm, and 251nm. Figure 30 It is found that the peak emission wavelength is around 494 nm (excitation wavelength 410 nm). The compound of one embodiment of the present invention can be used as a host material for a light-emitting substance or a host material for a fluorescent substance in the visible region.

[0530] In addition, the 6BP-4mPCBBiPPm film is not easy to agglomerate in the atmosphere, has little morphological change, and has good film quality.

[0531] Next, the HOMO and LUMO energy levels of 6BP-4mPCBBiPPm were calculated using cyclic voltammetry (CV) measurements. The calculation method was the same as in Example 1.

[0532] The results show that the HOMO energy level of 6BP-4mPCBBiPPm, measured as the oxidation potential Ea [V], was -5.45 eV, and the LUMO energy level was -2.84 eV. Furthermore, a comparison of the waveforms from the first and 100th repeated measurements of the oxidation-reduction wave revealed that 89% of the peak intensity was retained in the Ea measurement, while 90% of the peak intensity was retained in the Ec measurement. This demonstrates that 6BP-4mPCBBiPPm has very high resistance to oxidation and reduction.

[0533] Example 5

[0534] In this embodiment, the synthesis method of 4,6-bis{4-[N-(biphenyl-4-yl)-N-(9,9-dimethyl-9H-fluoren-2-yl)]aminophenyl}pyrimidine (abbreviation: 4,6FBiP2Pm) (structural formula (104)), which is one of the organic compounds according to one embodiment of the present invention, and the physical properties of the compound are described.

[0535] <Synthesis example 5>

[0536] Step 1: Synthesis of 4,6-bis{4-[N-(biphenyl-4-yl)-N-(9,9-dimethyl-9H-fluoren-2-yl)]aminophenyl}pyrimidine (abbreviation: 4,6FBiP2Pm)

[0537] Into a 200 mL three-necked flask were poured 1.3 g (4.2 mmol) of 4,6-bis(4-chlorophenyl)pyrimidine, 3.8 g (11 mmol) of N-(biphenyl-4-yl)-9,9-dimethyl-9H-fluoren-2-amine, 0.15 g (0.42 mmol) of di(1-adamantane)-n-butylphosphine, and 2.43 g (25 mmol) of sodium tert-butoxide. 40 mL of toluene was added to the mixture. The mixture was stirred while degassing under reduced pressure. 48 mg (0.084 mmol) of bis(dibenzylideneacetone)palladium(0) was added to the mixture, and the mixture was stirred at 110°C for 14.5 hours under a nitrogen stream. After stirring, toluene was added to the mixture, and the mixture was filtered using magnesium silicate, diatomaceous earth, and alumina to obtain a filtrate. The obtained filtrate was concentrated to obtain a solid. The solid was purified by silica gel column chromatography (developing solvent: toluene, followed by toluene:ethyl acetate = 50:1) to obtain a solid. The solid was purified by silica gel column chromatography (developing solvent: toluene, followed by toluene:ethyl acetate = 500:1) to obtain a solid. The obtained solid was recrystallized from toluene / ethanol to obtain a yellow solid. The obtained solid was recrystallized again from toluene / ethanol to obtain 2.9 g of a yellow solid in a yield of 71%. The synthesis scheme for Step 1 is shown below in Formula (A-5).

[0538] (A-5)

[0539]

[0540] The nuclear magnetic resonance spectroscopy of the obtained solid is shown below ( 1 1H NMR) analytical data.

[0541] 1H NMR (DMSO-d6, 300MHz): δ=1.42 (s, 12H), 7.10-7.16 (m, 6H), 7.23 (d, J1=8.7Hz, 4H), 7.27-7.37 (m, 8H), 7.41-7.50 (m, 6 H), 7.64-7.67 (m, 8H), 7.74 (d, J1=7.8Hz, 2H), 7.79 (d, J1=8.4Hz, 2H), 8.22 (d, J1=8.1Hz, 4H), 8.31 (s, 1H), 9.12 (s, 1H)

[0542] in addition, Figure 31A and Figure 31B The obtained solid 1 H NMR spectrum. Figure 31B yes Figure 31A The enlarged view of the range from 7.0 ppm to 9.5 ppm in FIG. 4,6 FBiP2Pm was obtained from the measurement results.

[0543] <4.6FBiP2Pm Characteristics>

[0544] then, Figure 32 The absorption spectrum and emission spectrum of the toluene solution of 4,6FBiP2Pm are shown. Figure 33 The absorption spectrum and emission spectrum of the thin film are shown. The measurement method is the same as that of Example 1 shown above.

[0545] Depend on Figure 32 It can be seen that the absorption peaks of the toluene solution of 4,6FBiP2Pm are observed near 403nm, 356nm, and 282nm. Figure 32 It can be seen that the peak of the luminescence wavelength is 457nm (excitation wavelength 408nm). Figure 33 It can be seen that the absorption peaks of the 4,6FBiP2Pm film are observed near 407nm, 360nm, 335nm, 290nm, 261nm, and 208nm. Figure 33 It is found that the peak emission wavelength is around 488 nm (excitation wavelength 400 nm). The compound of one embodiment of the present invention can be used as a host material for a light-emitting substance or a host material for a fluorescent substance in the visible region.

[0546] In addition, the 4,6FBiP2Pm film is not easy to aggregate in the atmosphere, has little morphological change, and has good film quality.

[0547] Next, the HOMO and LUMO energy levels of 4,6FBiP2Pm were calculated using cyclic voltammetry (CV) measurements. The calculation method was the same as in Example 1.

[0548] The results show that the HOMO energy level of 4,6FBiP2Pm, measured as the oxidation potential Ea [V], was -5.49 eV, and the LUMO energy level was -2.72 eV. Furthermore, a comparison of the waveforms from the first and 100th measurements of the repeated oxidation-reduction wave shows that 93% of the peak intensity was maintained in the Ea measurement, while 70% of the peak intensity was maintained in the Ec measurement. This demonstrates that 4,6FBiP2Pm has very high resistance to oxidation and reduction.

[0549] Example 6

[0550] In this embodiment, the synthesis method of 4,6-bis{3-[N-(biphenyl-4-yl)-N-(9,9-dimethyl-9H-fluorene-2-yl)]aminophenyl}pyrimidine (abbreviation: 4,6mFBiP2Pm) (structural formula (105)), which is one of the organic compounds according to one embodiment of the present invention, and the physical properties of the compound are described.

[0551] <Synthesis example 6>

[0552] Step 1: Synthesis of 4,6-bis{3-[N-(biphenyl-4-yl)-N-(9,9-dimethyl-9H-fluoren-2-yl)]aminophenyl}pyrimidine (abbreviated as: 4,6mFBiP2Pm)

[0553] Into a 200 mL three-necked flask were poured 1.3 g (4.2 mmol) of 4,6-bis(3-chlorophenyl)pyrimidine, 3.8 g (11 mmol) of N-(biphenyl-4-yl)-9,9-dimethyl-9H-fluorene-2-amine, 151 mg (0.42 mmol) of di(1-adamantane)-n-butylphosphine, and 2.4 g (25 mmol) of sodium tert-butoxide. 40 mL of toluene was added to the mixture. The mixture was stirred while degassing under reduced pressure. 48 mg (0.084 mmol) of bis(dibenzylideneacetone)palladium(0) was added to the mixture and stirred at 110°C for 34.5 hours under a nitrogen stream. After stirring, toluene was added to the mixture and suction filtered using magnesium silicate, diatomaceous earth, and alumina to obtain a filtrate. The obtained filtrate was concentrated to obtain a solid. The solid was purified by silica gel column chromatography (developing solvent: hexane:toluene = 2:1, followed by toluene) to obtain a solid. The solid was then purified by high-performance liquid chromatography using chloroform as the developing solvent. The resulting fraction was concentrated to obtain a solid. Hexane was added to the resulting solid, ultrasonically irradiated, and filtered to obtain 1.6 g of a yellow solid in a 41% yield. The synthesis scheme for Step 1 is shown below in Formula (A-6).

[0554] (A-6)

[0555]

[0556] 1.4 g of the obtained solid was purified by sublimation using a gradient sublimation method. The solution was heated at 355° C. under a pressure of 2.9 Pa and an argon flow rate of 15 mL / min. After sublimation purification, 1.3 g of a yellow solid was obtained at a recovery rate of 91%.

[0557] The nuclear magnetic resonance spectroscopy of the obtained solid is shown below ( 1 1H NMR) analytical data.

[0558] 1 H NMR (DMSO-d6, 300MHz): δ=1.38 (s, 12H), 7.05 (dd, J1=8.1Hz, J2=1.8Hz, 2H), 7.16 (d, J1=8.7Hz, 4H), 7.24-7.36 (m, 10H), 7 .42-7.54(m, 8H), 7.64-7.68(m, 8H), 7.77(t, J1=8.1Hz, 4H), 8.03(d, J1=7.8Hz, 2H), 8.10(s, 2H), 8.51(s, 1H), 9.11(s, 1H)

[0559] in addition, Figure 34A and Figure 34B The obtained solid 1 H NMR spectrum. Figure 34B yes Figure 34A The enlarged view of the range from 7.0 ppm to 9.5 ppm in FIG. 4 shows that 4,6 mFBiP2Pm was obtained from the measurement results.

[0560] <4.6mFBiP2Pm Characteristics>

[0561] then, Figure 35 The absorption and emission spectra of the toluene solution of 4,6mFBiP2Pm are shown. Figure 36 The absorption spectrum and emission spectrum of the thin film are shown. The measurement method is the same as that of Example 1 shown above.

[0562] Depend on Figure 35 It can be seen that the absorption peak of the toluene solution of 4,6mFBiP2Pm is observed near 364nm. Figure 35 It can be seen that the peak of the luminescence wavelength is 498nm (excitation wavelength 348nm). Figure 36 It can be seen that the absorption peaks of the 4,6mFBiP2Pm film are observed near 450nm, 348nm, 305nm, 275nm, 249nm, and 207nm. Figure 36It is found that the peak emission wavelength is around 512 nm (excitation wavelength 400 nm). The compound of one embodiment of the present invention can be used as a host material for a light-emitting substance or a host material for a fluorescent substance in the visible region.

[0563] In addition, the 4,6mFBiP2Pm film is not easy to aggregate in the atmosphere, has little morphological change, and has good film quality.

[0564] Next, the HOMO and LUMO energy levels of 4,6mFBiP2Pm were calculated using cyclic voltammetry (CV) measurements. The calculation method was the same as in Example 1.

[0565] The results show that the HOMO energy level of 4,6mFBiP2Pm, measured as the oxidation potential Ea [V], was -5.46 eV, and the LUMO energy level was -2.80 eV. Furthermore, a comparison of the waveforms from the first and 100th measurements of the repeated oxidation-reduction wave shows that 97% of the peak intensity was maintained in the Ea measurement, while 70% of the peak intensity was maintained in the Ec measurement. This demonstrates that 4,6mFBiP2Pm has very high resistance to oxidation and reduction.

[0566] Example 7

[0567] In this example, the synthesis method of N-(4-biphenyl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-4-[3-(dibenzo[f,h]quinoxaline-2-yl)phenyl]phenylamine (abbreviation: 2mpFBiBPDBq) (structural formula (106)), which is one of the organic compounds according to one embodiment of the present invention, and the physical properties of the compound are described.

[0568] <Synthesis Example 7>

[0569] Step 1: Synthesis of N-(4-biphenyl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-4-[3-(dibenzo[f,h]quinoxalin-2-yl)phenyl]phenylamine (abbreviated as: 2mpFBiBPDBq)

[0570] Into a 200 mL three-necked flask were placed 2.0 g (3.9 mmol) of N-(4-bromophenyl)-N-(4-biphenyl)-9,9-dimethyl-9H-fluoren-2-amine, 1.7 g (3.9 mmol) of 4,4,5,5-tetramethyl-2-[3-(dibenzo[f,h]quinoxalin-2-yl)phenyl]-1,3,2-dioxaborolane, 24 mg (0.078 mmol) of tri(o-tolyl)phosphine, and 1.1 g (7.8 mmol) of potassium carbonate. The atmosphere in the flask was purged with nitrogen. To this mixture were added 15 mL of toluene, 4.5 mL of ethanol, and 4.0 mL of water, and the mixture was degassed with stirring under reduced pressure. After degassed, 8.8 mg (0.078 mmol) of palladium(II) anhydride was added, and the mixture was stirred at approximately 80°C for 7 hours. After stirring, the mixture was filtered to obtain a solid. The obtained solid was dissolved in about 30 mL of heated toluene, and the solid was purified by silica gel column chromatography (developing solvent: hexane: toluene = 9:1) to obtain a solid. The obtained solid was purified by high-speed liquid chromatography (HPLC) to obtain a solid. The obtained solid was recrystallized using toluene / hexane to obtain 1.7 g of the target product as a light yellow solid with a yield of 59%. The synthesis scheme of step 1 is shown in the following formula (A-7).

[0571]

[0572] The nuclear magnetic resonance spectroscopy of the obtained solid is shown below ( 1 1H NMR) analytical data.

[0573] 1 H NMR (CDCl3, 500MHz): δ=1.47 (s, 6H), 7.17 (dd, J1=8.5Hz, J2=2.0Hz, 1H), 7.27- 7.35 (m, 8H), 7.41-7.46 (m, 3H), 7.56 (d, J=9.0Hz, 2H), 7.61-7.69 (m, 7H), 7.76 -7.84 (m, 5H), 8.28, (d, J = 8.0Hz, 1H), 8.60 (s, 1H), 8.66 (d, J = 8.0Hz, 2H), 9.25 (dd, J1=8.0Hz, J2=2.0Hz, 1H), 9.44 (dd, J1=8.0Hz, J2=2.0Hz, 1H), 9.46 (s, 1H)

[0574] in addition, Figure 37A and Figure 37B The obtained solid 1 H NMR spectrum. Figure 37B yes Figure 37AThe measurement results show that 2mpFBiBPDBq was obtained.

[0575] <Features of 2mpFBiBPDBq>

[0576] then, Figure 38 The absorption spectrum and emission spectrum of 2mpFBiBPDBq in toluene are shown. Figure 39 The absorption spectrum and emission spectrum of the thin film are shown. The measurement method is the same as that of Example 1 shown above.

[0577] Depend on Figure 38 It can be seen that the absorption peak of the toluene solution of 2mpFBiBPDBq is observed near 361nm. Figure 38 It can be seen that the peak of the luminescence wavelength is 466nm (excitation wavelength 366nm). Figure 39 It can be seen that the absorption peaks of the 2mpFBiBPDBq film are observed near 366nm, 311nm, 260nm, and 211nm. Figure 39 It is found that the peak emission wavelength is around 513 nm (excitation wavelength 384 nm). The compound of one embodiment of the present invention can be used as a host material for a light-emitting substance or a host material for a fluorescent substance in the visible region.

[0578] In addition, the thin film of 2mpFBiBPDBq is not easily aggregated in the atmosphere, has little morphological change, and has good film quality.

[0579] Next, the HOMO and LUMO levels of 2mpFBiBPDBq were calculated using cyclic voltammetry (CV) measurements. The calculation method was the same as in Example 1.

[0580] These results show that the HOMO level of 2mpFBiBPDBq, measured as its oxidation potential Ea [V], was -5.42 eV, and its LUMO level was -2.93 eV. Furthermore, a comparison of the waveforms from the first and 100th measurements of the repeated oxidation-reduction wave revealed that 91% of the peak intensity was retained in the Ea measurement, while 86% of the peak intensity was retained in the Ec measurement. This demonstrates that 2mpFBiBPDBq exhibits very high resistance to oxidation and reduction.

[0581] 2mpFBiBPDBq was also subjected to thermogravimetry-differential thermal analysis (TG-DTA). A high-vacuum differential thermogravimetric analyzer (TG-DTA2410SA, manufactured by Bruker AXS K.K.) was used for the measurement. Measurements were performed under a nitrogen flow (flow rate of 200 mL / min) and atmospheric pressure at a heating rate of 10°C / min. The relationship between weight and temperature (thermogravimetric analysis) revealed that the 5% weight loss temperature of 2mpFBiBPDBq was above 500°C. This indicates that 2mpFBiBPDBq has excellent heat resistance.

[0582] Example 8

[0583] In this embodiment, the synthesis method of N-(4-biphenyl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-(4-{3-[6-(9,9-dimethyl-9H-fluoren-2-yl)pyrimidin-4-yl]phenyl}phenyl)amine (abbreviation: 6FL-4mpFBiBPPm) (structural formula (107)), which is one of the organic compounds according to one embodiment of the present invention, and the physical properties of the compound are described.

[0584] <Synthesis example 8>

[0585] Step 1: Synthesis of 4-chloro-6-(9,9-dimethyl-9H-fluoren-2-yl)pyrimidine

[0586] A 200 mL three-necked flask was charged with 13.0 g (87 mmol) of 4,6-dichloropyrimidine, 13 g (40 mmol) of 4,4,5,5-tetramethyl-2-(9,9-dimethyl-9H-fluorene-2-yl)-1,3,2-dioxaborolane, and 13.0 g (120 mmol) of sodium carbonate, and the flask was purged with nitrogen. 200 mL of 1,4-dioxane and 60 mL of water were added to the flask, and the mixture was stirred under reduced pressure to degas. After degassing, 0.3 g (0.40 mmol) of bis(triphenylphosphine)palladium(II) dichloride was added to the mixture, and microwave irradiation was performed for 8 hours at 400 W. After irradiation for a predetermined time, the mixture was filtered, and the aqueous layer of the filtrate was extracted with toluene, and then the organic layer and the mixture were washed with saturated brine. Utilize magnesium sulfate to dry this solution, and this mixture is gravity filtered to obtain filtrate.The oily matter obtained by concentrating the filtrate obtained is added 20mL of toluene, and utilize diatomaceous earth · alumina · magnesium silicate to carry out suction filtration to this solution.Utilize high-speed liquid chromatography (HPLC) to purify the oily matter obtained by concentrating the filtrate obtained, and obtain oily matter by concentrating the obtained fraction. The obtained oily matter is dried under reduced pressure to obtain 7.3g of light brown oily matter of target object with a yield of 60%.By repeating twice above-mentioned series of operations, obtain 15g of light brown oily matter of 4-chloro-6-(9,9-dimethyl-9H-fluorene-2-yl) pyrimidine of target object.The synthetic scheme of step 1 is shown in following formula (A-8).

[0587] (A-8)

[0588]

[0589] Step 2: Synthesis of 4-(3-chlorophenyl)-6-(9,9-dimethyl-9H-fluoren-2-yl)pyrimidine

[0590] Into a 200 mL three-necked flask were poured 10 g (32 mmol) of 4-chloro-6-(9,9-dimethyl-9H-fluoren-2-yl)pyrimidine, 5.0 g (32 mmol) of 3-chlorophenylboronic acid, 0.19 g (0.64 mmol) of tri(o-o-tolyl)phosphine, and 8.8 g (64 mmol) of potassium carbonate, and the atmosphere in the flask was purged with nitrogen. 140 mL of toluene, 20 mL of ethanol, and 32 mL of water were added to the mixture, and the mixture was degassed while stirring under reduced pressure. After degassing, 72 mg (0.32 mmol) of palladium (II) anhydride was added to the mixture, and the mixture was stirred at approximately 80°C for 27 hours. After stirring, the aqueous layer of the mixture was extracted with toluene, and then the aqueous layer and the organic layer were washed with saturated brine. The solution was dried over magnesium sulfate, and the mixture was gravity filtered to obtain a filtrate. The obtained filtrate is concentrated to obtain an oily substance, and 20 mL of toluene is added, and the solution is filtered using diatomaceous earth, alumina, and magnesium silicate. The oily substance obtained by concentrating the obtained filtrate is purified using high-speed liquid chromatography (HPLC), and the oily substance is obtained by concentrating the obtained fraction. The obtained oily substance is dried under reduced pressure to obtain 6.0 g of a light brown oily substance of 4-(3-chlorophenyl)-6-(9,9-dimethyl-9H-fluorene-2-yl) pyrimidine of the target substance in a yield of 50%. The synthesis scheme of step 2 is shown in the following formula (A-9).

[0591] (A-9)

[0592]

[0593] Step 3: Synthesis of 4,4,5,5-tetramethyl-2-{3-[6-(9,9-dimethyl-9H-fluoren-2-yl)pyrimidin-4-yl]phenyl}-1,3,2-dioxaborolane

[0594] In a 200 mL three-necked flask, 6.0 g (15 mmol) of 4-(3-chlorophenyl)-6-(9,9-dimethyl-9H-fluoren-2-yl)pyrimidine, 5.0 g (20 mmol) of bis(valeryl)diboron, 0.14 g (0.40 mmol) of bis(1-adamantane)-n-butylphosphine, and 3.9 g (40 mmol) of potassium oxalate were placed, and the atmosphere was purged with nitrogen. 80 mL of xylene was added to the mixture, and the mixture was degassed while stirring under reduced pressure. The mixture was heated to 40°C, and 0.16 g (0.20 mmol) of [1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium(II) dichloromethane adduct was added. The mixture was stirred at 140°C for 17 hours under a nitrogen stream. After stirring, the mixture was suction filtered, and the filtrate was concentrated to obtain an oil. The resulting oil was purified by silica gel column chromatography (developing solvent: hexane:toluene = 2:1) to yield an oil. The resulting oil was dried under reduced pressure to yield 2.9 g of the target compound, 4,4,5,5-tetramethyl-2-{3-[6-(9,9-dimethyl-9H-fluoren-2-yl)pyrimidin-4-yl]phenyl}-1,3,2-dioxaborolane, as a pale yellow oil in a 41% yield. The synthesis scheme for Step 3 is shown in Formula (A-10).

[0595]

[0596] Step 4: Synthesis of N-(4-biphenyl)-N-(9,9-dimethyl-9H-fluoren-2-yl)-(4-{3-[6-(9,9-dimethyl-9H-fluoren-2-yl)pyrimidin-4-yl]phenyl}phenyl)amine (abbreviated as: 6FL-4mpFBiBPPm)

[0597] Into a 100 mL three-necked flask were placed 1.5 g (3.0 mmol) of N-(4-bromophenyl)-N-(4-biphenyl)-9,9-dimethyl-9H-fluoren-2-amine, 1.4 g (3.0 mmol) of 4,4,5,5-tetramethyl-2-{3-[6-(9,9-dimethyl-9H-fluoren-2-yl)pyrimidin-4-yl]phenyl}-1,3,2-dioxaborolane, 18 mg (0.060 mmol) of tri(o-tolyl)phosphine, and 0.83 g (6.0 mmol) of potassium carbonate. The atmosphere in the flask was purged with nitrogen. To this mixture were added 12 mL of toluene, 3.0 mL of ethanol, and 3.0 mL of water, and the mixture was degassed with stirring under reduced pressure. After degassing, 6.7 mg (0.039 mmol) of palladium (II) anhydride was added to the mixture and stirred at about 80°C for 8 hours. After stirring, the aqueous layer of the mixture was extracted with toluene, and the aqueous layer and the organic layer were washed with saturated brine. The solution was dried over magnesium sulfate, and the mixture was gravity filtered to obtain a filtrate. The filtrate was concentrated by silica gel column chromatography (developing solvent: toluene) to obtain an oily substance. The obtained oily substance was purified by high-speed liquid chromatography (HPLC) to obtain a solid. The obtained solid was washed with hexane to obtain 0.89 g of the target substance as a light yellow solid with a yield of 37%. The synthesis scheme of step 4 is shown in the following formula (A-11).

[0598] (A-11)

[0599]

[0600] 0.82 g of the resulting pale yellow solid was purified by gradient sublimation. Sublimation purification conditions were a pressure of 10 Pa, an argon gas flow rate of 5.0 mL / min, and heating the pale yellow solid at 320°C. After sublimation purification, 0.65 g of a yellow solid containing 6 FL-4 mpFBi BPPm was obtained with a yield of 79%.

[0601] The nuclear magnetic resonance spectroscopy of the obtained solid is shown below ( 1 1H NMR) analytical data.

[0602] 1H NMR (CDCl3, 500MHz): δ=1.46 (s, 6H), 1.59 (s, 6H), 7.14 (dd, J1=8.5Hz, J2=2.0Hz, 1H), 7.25-7.53 (m, 14H), 7.54 (d, J=9.0Hz, 2H), 7.61-7.68 (m, 7H), 7.77-7.81 (m, 2H), 7.87 , (d, J=8.0Hz, 1H), 8.10, (d, J=8.0Hz, 1H), 8.14 (dd, J1=8.0Hz, J2=2.0Hz, 1H), 8.22, ( d, J=1.5Hz, 1H), 8.29, (d, J=1.5Hz, 1H), 8.41 (t, J=1.5Hz, 1H), 9.36, (d, J=1.5Hz, 1H)

[0603] in addition, Figure 40A and Figure 40B The obtained solid 1 H NMR spectrum. Figure 40B yes Figure 40A The measurement results show that 6FL-4mpFBiBPPm was obtained.

[0604] <Characteristics of 6FL-4mpFBiBPPm>

[0605] then, Figure 41 The absorption spectrum and emission spectrum of the toluene solution of 6FL-4mpFBiBPPm are shown. Figure 42 The absorption spectrum and emission spectrum of the thin film are shown. The measurement method is the same as that of Example 1 shown above.

[0606] Depend on Figure 41 It can be seen that the absorption peak of 6FL-4mpFBiBPPm toluene solution is observed near 346nm. Figure 41 It can be seen that the peak of the luminescence wavelength is 445nm (excitation wavelength 346nm). Figure 42 It can be seen that the absorption peaks of the 6FL-4mpFBiBPPm film are observed near 380nm, 348nm, 277nm, 215nm, and 207nm. Figure 42 It is found that the peak emission wavelength is around 490 nm (excitation wavelength 376 nm). The compound of one embodiment of the present invention can be used as a host material for a light-emitting substance or a host material for a fluorescent substance in the visible region.

[0607] In addition, the 6FL-4mpFBiBPPm film is not easily aggregated in the atmosphere, has little morphological change, and has good film quality.

[0608] Next, the HOMO and LUMO energy levels of 6FL-4mpFBiBPPm were calculated using cyclic voltammetry (CV) measurements. The calculation method was the same as in Example 1.

[0609] These results show that the HOMO level of the 6FL-4mpFBiBPPm oxidation potential (Ea [V]) was -5.42 eV, and the LUMO level was -2.80 eV. Furthermore, a comparison of the waveforms from the first and 100th repeated measurements of the oxidation-reduction wave revealed that 93% of the peak intensity was retained in the Ea measurement, while 83% of the peak intensity was retained in the Ec measurement. This demonstrates that 6FL-4mpFBiBPPm exhibits very high resistance to oxidation and reduction.

[0610] Example 9

[0611] In this embodiment, the synthesis method of N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-N-(9,9-dimethyl-9H-fluorene-2-yl)-(4-{3-[6-(9,9-dimethyl-9H-fluorene-2-yl)pyrimidin-4-yl]phenyl}phenyl)amine (abbreviation: 6FL-4mpPCBFBPPm) (structural formula (108)), which is one of the organic compounds according to one embodiment of the present invention, and the physical properties of the compound are described.

[0612] <Synthesis Example 9>

[0613] Synthesis of (N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-N-(9,9-dimethyl-9H-fluoren-2-yl)-(4-{3-[6-(9,9-dimethyl-9H-fluoren-2-yl)pyrimidin-4-yl]phenyl}phenyl)amine (abbreviated as: 6FL-4mpPCBFBPPm))

[0614] Into a 100 mL three-necked flask were placed 1.7 g (2.7 mmol) of N-(4-chlorophenyl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9-dimethyl-9H-fluoren-2-amine, 1.3 g (2.7 mmol) of 4,4,5,5-tetramethyl-2-{3-[6-(9,9-dimethyl-9H-fluoren-2-yl)pyrimidin-4-yl]phenyl}-1,3,2-dioxaborolane, 1.9 g (9.0 mmol) of tripotassium phosphate, and 22 mg (0.060 mmol) of bis(1-adamantane)-n-butylphosphine, and the atmosphere was purged with nitrogen. To this mixture were added 15 mL of 1,4-dioxane and 0.67 g (9.0 mmol) of tert-butanol. The mixture was stirred while reducing the pressure to degas. After degassing, 6.7 mg (0.030 mmol) of palladium (II) anhydride was added to the mixture and stirred at about 80°C for 14 hours. After stirring, the mixture was filtered, and the filtrate was concentrated by silica gel column chromatography (developing solvent: toluene) to obtain an oily substance. The obtained oily substance was washed with hexane to obtain 1.4 g of the target substance as a yellow solid with a yield of 54%. The synthesis scheme of step 1 is shown in the following formula (A-12).

[0615]

[0616] The nuclear magnetic resonance spectroscopy of the obtained solid is shown below ( 1 1H NMR) analytical data.

[0617] 1 H NMR (CDCl3, 300MHz): δ=1.47 (s, 6H), 1.59 (s, 6H), 7.17 (dd, J1=8.4Hz, J2=1.8Hz, 1H), 7.28- 7.51 (m, 15H), 7.60-7.69 (m, 13H), 7.77-7.82 (m, 2H), 7.87 (d, J=8.4Hz, 1H), 8.11 (d, J=7.8H z, 1H), 8.15 (dd, J1=7.8Hz, J2=1.5Hz, 1H), 8.20, (d, J=7.5Hz, 1H), 8.22, (d, J=1.5Hz, 1H), 8 .29, (d, J=1.5Hz, 1H), 8.37, (d, J=1.5Hz, 1H), 8.42 (t, J=1.5Hz, 1H), 9.37, (d, J=0.9Hz, 1H)

[0618] in addition, Figure 43A and Figure 43B The obtained solid 1H NMR spectrum. Figure 43B yes Figure 43A The measurement results show that 6FL-4mpPCBFBPPm was obtained.

[0619] <Characteristics of 6FL-4mpPCBFBPPm>

[0620] then, Figure 44 The absorption spectrum and emission spectrum of a toluene solution of 6FL-4mpPCBFBPPm are shown.

[0621] Depend on Figure 44 It can be seen that the absorption peak of 6FL-4mpPCBFBPPm toluene solution is observed near 346nm. Figure 44 It is found that the peak emission wavelength is 448 nm (excitation wavelength 346 nm). The compound of one embodiment of the present invention can be used as a host material for a light-emitting substance or a host material for a fluorescent substance in the visible region.

[0622] Next, the HOMO and LUMO energy levels of 6FL-4mpPCBFBPPm were calculated using cyclic voltammetry (CV) measurements. The calculation method was the same as in Example 1.

[0623] From these results, it was found that the HOMO energy level of 6FL-4mpPCBFBPPm was -5.37 eV and the LUMO energy level was -2.81 eV in the measurement of the oxidation potential Ea [V].

[0624] Example 10

[0625] In this embodiment, the synthesis method of N-[4-(9-phenyl-9H-carbazole-3-yl)phenyl]-N-{4-[6-(9,9-dimethyl-9H-fluorene-2-yl)pyrimidin-4-yl]phenyl}-1,1'-biphenyl-4-amine (abbreviation: 6FL-4PCBBiPPm) (structural formula (109)), which is one of the organic compounds according to one embodiment of the present invention, and the physical properties of the compound are described.

[0626] <Synthesis example 10>

[0627] Step 1: Synthesis of N-(4-chlorophenyl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-1,1'-biphenyl-4-amine

[0628] Pour 2.92 g (6.0 mmol) of N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-1,1'-biphenyl-4-amine, 1.73 g (18 mmol) of sodium tert-butoxide, 1.50 g (6.3 mmol) of 4-chloroiodobenzene and 30 mL of toluene into the reaction vessel. Stir the mixture while reducing pressure to degas, and replace the reaction vessel with nitrogen. Then, add 34.5 mg (0.06 mmol) of bis(dibenzylideneacetone)palladium(0) and 0.36 mL (0.12 mmol) of tri(tert-butyl)phosphine (10 wt% hexane solution). The mixture is stirred at 85°C for 5 hours under a nitrogen stream. Then, the mixture is cooled to room temperature and 350 ml of toluene is added and stirred, and then the solid is filtered out by suction. The filtrate obtained by concentration obtains about 100 mL of a brown liquid. The brown liquid is purified using diatomaceous earth, alumina and magnesium silicate. The resulting filtrate was concentrated and recrystallized with ethanol to yield 3.60 g of a pale yellow solid. This pale yellow solid was heated with ethanol and stirred, then filtered to yield 2.29 g of the desired compound as a pale yellow powder in a 64% yield. The synthesis scheme for Step 1 is shown in Formula (A-13).

[0629]

[0630] Step 2: Synthesis of N-[4-(4,4,5,5-tetramethyl-1,3,2-dioxaborolane-2-yl)phenyl]-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-1,1'-biphenyl-4-amine

[0631] A reaction vessel was charged with 1.49 g (2.5 mmol) of N-(4-chlorophenyl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-1,1'-biphenyl-4-amine, 0.95 g (3.75 mmol) of bis(valeryl)diboron, 0.74 g (7.5 mmol) of potassium oxalate, and 30 mL of ethylene glycol dimethyl ether. The mixture was degassed while stirring under reduced pressure, and the atmosphere in the reaction vessel was purged with nitrogen. The reaction vessel was then heated and stirred to approximately 60°C, followed by the addition of 20.4 mg (0.025 mmol) of [1,1'-bis(diphenylphosphino)ferrocene]dichloropalladium(II) dichloromethane adduct and 20.5 mg (0.050 mmol) of 2-dichlorohexylphosphino-2',6'-dimethoxybiphenyl. The mixture was heated under reflux and stirred for 19 hours under a nitrogen stream. Then, the mixture was cooled to room temperature and concentrated with toluene to obtain approximately 50 mL of a brown liquid. The brown liquid was purified using diatomaceous earth and silica gel. The resulting filtrate was concentrated and recrystallized with ethanol to obtain 1.34 g of a yellow powder of the desired product in a yield of 78%. The synthesis scheme of step 2 is shown in the following formula (A-14).

[0632]

[0633] Step 3: Synthesis of N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-N-{4-[6-(9,9-dimethyl-9H-fluoren-2-yl)pyrimidin-4-yl]phenyl}-1,1'-biphenyl-4-amine (abbreviated as 6FL-4PCBBiPPm)

[0634] A reaction vessel was charged with 1.38 g (2.0 mmol) of N-(4-chlorophenyl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-1,1'-biphenyl-4-amine, 0.61 g (2.0 mmol) of 4-chloro-6-(9,9-dimethyl-9H-fluoren-2-yl)pyrimidine, 1.27 g (6.0 mmol) of tripotassium phosphate, and 20 mL of diethylene glycol dimethyl ether (diglyme). The mixture was stirred under reduced pressure to deaerate, and the atmosphere in the reaction vessel was purged with nitrogen. The reaction vessel was then heated and stirred at approximately 60°C, followed by the addition of 4.5 mg (0.02 mmol) of palladium(II) anhydride and 14.3 mg (0.04 mmol) of bis(1-adamantyl)-n-butylphosphine. The mixture was heated to 120°C and stirred under a nitrogen stream for 24 hours. The mixture was then cooled to room temperature and extracted and washed with toluene and water to obtain a black solution. Magnesium sulfate was added to the solution, the water was removed by filtration, and a black solution was obtained by concentration. The solution was subjected to column purification using silica gel using a mixed solvent of toluene:ethyl acetate = 100:1 as the developing solvent. The obtained solution was concentrated and then recrystallized by adding ethanol to obtain 1.10 g of the target compound as a yellow powder with a yield of 66%. The synthesis scheme of step 3 is shown in the following formula (A-15).

[0635]

[0636] 1.10 g of the obtained yellow powder was purified by gradient sublimation. The yellow powder was heated at 370°C under a pressure of 3.23 Pa and an argon flow rate of 15 mL / min. After sublimation purification, 0.48 g of the target substance was obtained as a pale yellow solid with a recovery rate of 43%.

[0637] The nuclear magnetic resonance spectroscopy of the obtained solid is shown below ( 1 1H NMR) analytical data.

[0638] 1 H NMR (CDCl3, 500MHz): δ=1.58 (s, 6H), 7.31-7.40 (m, 10H), 7.44-7.50 (m, 7H), 7.57-7.71 (m, 11H), 7.80 (dd, J1=8.7Hz, J2=2.4Hz, 1 H), 7.87 (d, J=8.1Hz, 1H), 8.10-8.13 (m, 4H), 8.20 (d, J=8.4Hz, 1H), 8.26, (d, J=1.2Hz, 1H), 8.37, (s, 1H), 9.29, (d, J=1.2Hz, 1H)

[0639] in addition, Figure 45A and Figure 45BThe obtained solid 1 H NMR spectrum. Figure 45B yes Figure 45A The measurement results show that 6FL-4PCBBiPPm was obtained.

[0640] <Characteristics of 6FL-4PCBBiPPm>

[0641] then, Figure 46 The absorption spectrum and emission spectrum of the toluene solution of 6FL-4PCBBiPPm are shown. Figure 47 The absorption spectrum and emission spectrum of the thin film are shown. The measurement method is the same as that of Example 1 shown above.

[0642] Depend on Figure 46 It can be seen that the absorption peaks of 6FL-4PCBBiPPm toluene solution are observed near 394nm and 338nm. Figure 46 It can be seen that the peak of the luminescence wavelength is 467nm (excitation wavelength 394nm). Figure 47 It can be seen that the absorption peaks of the 6FL-4PCBBiPPm film are observed near 400nm, 335nm, 309nm, 287nm, 242nm, and 207nm. Figure 47 It is found that the peak emission wavelength is around 505 nm (excitation wavelength 410 nm). The compound of one embodiment of the present invention can be used as a host material for a light-emitting substance or a host material for a fluorescent substance in the visible region.

[0643] In addition, the 6FL-4PCBBiPPm film is not easy to agglomerate in the atmosphere, has little morphological change, and has good film quality.

[0644] Next, the HOMO and LUMO energy levels of 6FL-4PCBBiPPm were calculated using cyclic voltammetry (CV) measurements. The calculation method was the same as in Example 1.

[0645] The results show that the HOMO energy level of 6FL-4PCBBiPPm, measured as the oxidation potential Ea [V], was -5.48 eV, and the LUMO energy level was -2.80 eV. Furthermore, a comparison of the waveforms from the first and 100th measurements of the repeated oxidation-reduction wave shows that 81% of the peak intensity was retained in the Ea measurement, while 86% of the peak intensity was retained in the Ec measurement. This demonstrates that 6FL-4PCBBiPPm has very high resistance to oxidation and reduction.

[0646] Example 11

[0647] In this example, examples of manufacturing Light-Emitting Elements 2 to 5, which are light-emitting elements according to one embodiment of the present invention, and Comparative Light-Emitting Element 1 are shown. In Comparative Light-Emitting Element 1 and Light-Emitting Elements 2 to 5, two host materials and one guest material are used in the light-emitting layer. Two bipolar materials are used as the host materials. The electron-accepting bipolar material (the one with the lower LUMO energy level) in the light-emitting layer is 2-[3'-(dibenzothiophene-4-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviated as 2mDBTBPDBq-II), as shown below. The hole-accepting bipolar material (the one with the higher HOMO energy level) is different in each element, allowing comparison of their device characteristics. Figure 48 Table 1 shows a schematic cross-sectional view of the light-emitting element fabricated in this example. Details of the element structure are provided in Table 1. Table 2 shows the LUMO energy level difference estimated by CV measurements between the two bipolar materials used in the light-emitting layer of each element. The structures and abbreviations of the compounds used are shown below. The structures and abbreviations of other compounds can be found in the above examples.

[0648]

[0649] [Table 1]

[0650]

[0651] [Table 2]

[0652]

[0653] <Manufacturing of Light-Emitting Element>

[0654] Manufacturing of Comparative Light-Emitting Element 1

[0655] A 70 nm thick ITSO film is formed on the substrate 200 as the electrode 101. The electrode 101 has an electrode area of 4 mm 2 (2mm×2mm).

[0656] Next, as a hole injection layer 111, 4,4',4"-(benzene-1,3,5-triyl)tris(dibenzothiophene) (abbreviated as DBT3P-II) and molybdenum oxide (MoO3) were co-evaporated on the electrode 101 in a weight ratio (DBT3P-II:MoO3) of 1:0.5 and a thickness of 60 nm.

[0657] Next, 4-phenyl-4′-(9-phenylfluoren-9-yl)triphenylamine (BPAFLP) was deposited on the hole injection layer 111 to a thickness of 20 nm to form the hole transport layer 112 .

[0658] Next, 2mDBTBPDBq-II, N-(1,1'-biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazol-3-yl)phenyl]-9,9-dimethyl-9H-fluorene-2-amine (abbreviated as PCBBiF), bis[2-(6-tert-butyl-4-pyrimidinyl-κN- 3 )phenyl-κC](2,4-pentanedionato-κ 2 In the light-emitting layer 160, 2mDBTBPDBq-II is a bipolar material that accepts electrons, PCBBiF is a bipolar material that accepts holes, and Ir(tBuppm)2(acac) is a guest material (phosphorescent material).

[0659] Next, 2mDBTBPDBq-II was vapor-deposited to a thickness of 20 nm on the light-emitting layer 160 as the electron-transporting layer 118(1). Next, bathophenanthroline (BPhen) was vapor-deposited to a thickness of 10 nm as the electron-transporting layer 118(2). Next, lithium fluoride (LiF) was vapor-deposited to a thickness of 1 nm on the electron-transporting layer 118 as the electron-injecting layer 119.

[0660] Next, aluminum (Al) was formed to a thickness of 200 nm as the electrode 102 on the electron injection layer 119 .

[0661] Next, in a nitrogen atmosphere glove box, the substrate 220 was fixed to the substrate 200 on which the organic material was formed using an organic EL sealant, thereby sealing the comparative light-emitting element 1. Specifically, the sealant was applied to the edge of the substrate 220, and the substrate 220 and the substrate 200 on which the organic material was formed were attached. 2 The film was irradiated with ultraviolet light having a wavelength of 365 nm, and heat treated at 80° C. for 1 hour. Comparative Light-Emitting Element 1 was obtained through the above steps.

[0662] Manufacturing of Light-Emitting Element 2

[0663] The light emitting element 2 is the same as the comparative light emitting element 1 except that the material of the light emitting layer 160 is different. Other processes are the same as those of the comparative light emitting element 1.

[0664] That is, it is preferred that the light-emitting layer 160 of the light-emitting element 2 be co-evaporated with 40 nm of 2mDBTBPDBq-II, 6BP-4FBiPPm and Ir(tBuppm)2(acac) in a weight ratio of 0.6:0.4:0.05 (2mDBTBPDBq-II:6BP-4FBiPPm:Ir(tBuppm)2(acac)).

[0665] Manufacturing of Light-Emitting Element 3

[0666] The light emitting element 3 is the same as the comparative light emitting element 1 except that the material of the light emitting layer 160 is different. Other processes are the same as those of the comparative light emitting element 1.

[0667] That is, the light-emitting layer 160 of the light-emitting element 3 is co-deposited with 40 nm of 2mDBTBPDBq-II, 6BP-4PCBBiPPm and Ir(tBuppm)2(acac) in a weight ratio of 0.6:0.4:0.05 (2mDBTBPDBq-II:6BP-4PCBBiPPm:Ir(tBuppm)2(acac)).

[0668] Manufacturing of Light-Emitting Element 4

[0669] As the light-emitting layer 160 of the light-emitting element 4, 40 nm of 2mDBTBPDBq-II, 6BP-4mFBiPPm and Ir(tBuppm)2(acac) were co-deposited in a weight ratio (2mDBTBPDBq-II:6BP-4mFBiPPm:Ir(tBuppm)2(acac)) of 0.6:0.4:0.05.

[0670] Manufacturing of Light-Emitting Element 5

[0671] As the light-emitting layer 160 of the light-emitting element 5, 40 nm of 2mDBTBPDBq-II, 6BP-4mPCBBiPPm and Ir(tBuppm)2(acac) were co-deposited in a weight ratio (2mDBTBPDBq-II:6BP-4mPCBBiPPm:Ir(tBuppm)2(acac)) of 0.6:0.4:0.05.

[0672] <Characteristics of Light-Emitting Element>

[0673] Next, the characteristics of the comparative light-emitting elements 1, 2, to 5 manufactured above were measured. A colorimeter (BM-5A manufactured by Topcon Technohouse) was used for luminance and CIE chromaticity measurements. A multi-channel optical spectrum analyzer (PMA-11 manufactured by Hamamatsu Photonics Co., Ltd.) was used for electroemission spectrum measurements.

[0674] Figure 49 The current efficiency-luminance characteristics of the comparative light-emitting element 1, light-emitting element 2 to light-emitting element 5 are shown. Figure 50 The brightness-voltage characteristics are shown. Figure 51 shows the current density-voltage, Figure 52 The external quantum efficiency-brightness characteristics are shown. Figure 53 Shown at 2.5 mA / cm 2 The emission spectra when the current density is such that the current flows through the light-emitting element 1, the light-emitting element 2 to the light-emitting element 5 are compared.

[0675] In addition, Table 3 shows that 1000 cd / m 2 Element characteristics of the nearby comparative light-emitting elements 1, 2 to 5.

[0676] [Table 3]

[0677]

[0678] like Figure 53 As shown, the peak wavelength of the electric field emission spectra of the comparative light-emitting element 1, light-emitting element 2 to light-emitting element 5 is near 546 nm, and the full width at half maximum is 57 nm to 65 nm, respectively, showing green light emission.

[0679] like Figure 52 As shown in Table 3, the maximum external quantum efficiency of the comparative light-emitting element 1 is 26%, while the maximum external quantum efficiency of light-emitting elements 2 to 5 is above 28%, which are very high external quantum efficiencies.

[0680] in addition, Figure 54 The difference in LUMO energy level between the host materials of each device and 10mA / cm 2 The relationship between the driving voltage and the Figure 54 It can be seen that Light-emitting Element 2 to Light-emitting Element 5 exhibit lower driving voltages than Comparative Light-emitting Element 1. This is because the LUMO energy level difference between the two host materials used in the light-emitting layer is less than 0.5 eV and both host materials are bipolar materials.

[0681] Example 12

[0682] This example shows the fabrication of Light-Emitting Element 7, Light-Emitting Element 8, and Comparative Light-Emitting Element 6, which are light-emitting elements according to one embodiment of the present invention. In Comparative Light-Emitting Element 6, Light-Emitting Element 7, and Light-Emitting Element 8, two host materials and one guest material were used in the light-emitting layer. Two bipolar materials were used as the host materials. The electron-accepting bipolar material (lower LUMO level) in the light-emitting layer was 2mDBTBPDBq-II, while the hole-accepting bipolar material (higher HOMO level) in the light-emitting layer was different in each element, allowing for comparison of device characteristics. Figure 48 Table 4 shows a schematic cross-sectional view of the light-emitting element fabricated in this example. Table 5 shows the LUMO energy difference estimated by CV measurements between the two bipolar materials used in the light-emitting layer of each element. The structures and abbreviations of the compounds used are shown below. The structures and abbreviations of other compounds can be found in the above examples.

[0683]

[0684] [Table 4]

[0685]

[0686] [Table 5]

[0687]

[0688] <Manufacturing of Light-Emitting Element>

[0689] Comparative Manufacturing of Light-Emitting Element 6

[0690] The comparative light-emitting element 6 is the same as the comparative light-emitting element 1 except that the material of the light-emitting layer 160 is different. Other processes are the same as those of the comparative light-emitting element 1.

[0691] That is, the light-emitting layer 160 of the comparative light-emitting element 6 was co-deposited with 40 nm of 2mDBTBPDBq-II, PCBBiF, and bis[2-(6-phenyl-4-pyrimidinyl-κN]-1-yl ... 3 )phenyl-κC](2,4-pentanedionato-κ 2 O, O') iridium (III) (abbreviation: Ir(dppm)2(acac)).

[0692] Manufacturing of Light-Emitting Element 7

[0693] The light emitting element 7 is the same as the comparative light emitting element 1 except that the material of the light emitting layer 160 is different. Other processes are the same as those of the comparative light emitting element 1.

[0694] That is, the light-emitting layer 160 of the light-emitting element 7 is co-deposited with 40 nm of 2mDBTBPDBq-II, 6BP-4FBiPPm and Ir(dppm)2(acac) in a weight ratio of 0.6:0.4:0.05 (2mDBTBPDBq-II:6BP-4FBiPPm:Ir(dppm)2(acac)).

[0695] Manufacturing of Light-Emitting Element 8

[0696] The light emitting element 8 is the same as the comparative light emitting element 1 except that the material of the light emitting layer 160 is different. Other processes are the same as those of the comparative light emitting element 1.

[0697] That is, the light-emitting layer 160 of the light-emitting element 8 is co-deposited with 40 nm of 2mDBTBPDBq-II, 6BP-4PCBBiPPm and Ir(dppm)2(acac) in a weight ratio of 0.6:0.4:0.05 (2mDBTBPDBq-II:6BP-4PCBBiPPm:Ir(dppm)2(acac)).

[0698] <Characteristics of Light-Emitting Element>

[0699] Next, the characteristics of the comparative light-emitting element 6, the light-emitting element 7, and the light-emitting element 8 manufactured above were measured. The measurement method was the same as that of Example 11.

[0700] Figure 55 The current efficiency-luminance characteristics of the comparative light-emitting element 6, the light-emitting element 7, and the light-emitting element 8 are shown. Figure 56 The brightness-voltage characteristics are shown. Figure 57 The current density-voltage characteristics are shown. Figure 58 The external quantum efficiency-brightness characteristics are shown. Figure 59 Shown at 2.5 mA / cm 2 The emission spectra when the current density is such that the current flows through the comparison light-emitting element 6, the light-emitting element 7, and the light-emitting element 8.

[0701] In addition, Table 6 shows that 1000 cd / m 2 Element characteristics of nearby comparative light-emitting elements 6, 7, and 8.

[0702] [Table 6]

[0703]

[0704] like Figure 59 As shown, the peak wavelength of the electric field emission spectra of comparative light-emitting element 6, light-emitting element 7, and light-emitting element 8 is near 586 nm, and they each exhibit orange light emission with a full width at half maximum of 69 nm to 73 nm.

[0705] like Figure 58 As shown in Table 6, the maximum external quantum efficiency of the comparative light-emitting element 6 is 30%, while the maximum external quantum efficiency of the light-emitting element 7 and the light-emitting element 8 are both above 31%, which are very high external quantum efficiencies. Figure 58 It can be seen that Light-emitting Element 7 and Light-emitting Element 8 have higher external quantum efficiencies than Comparative Light-emitting Element 6. This is because the LUMO energy level difference between the two host materials used in the light-emitting layers of Light-emitting Element 7 and Light-emitting Element 8 is less than 0.5 eV, and both host materials are bipolar materials. This shows that Light-emitting Element 7 and Light-emitting Element 8 have better carrier balance than Comparative Light-emitting Element 6.

[0706] in addition, Figure 60 The difference in LUMO energy level between the host materials of each device and 10mA / cm 2 The relationship between the driving voltage and the Figure 60 It can be seen that Light-emitting Element 7 and Light-emitting Element 8 exhibit lower driving voltages than Comparative Light-emitting Element 6. This is because the LUMO energy level difference between the two host materials used in the light-emitting layer is less than 0.5 eV and both host materials are bipolar materials.

[0707] <Reliability of Light-Emitting Element>

[0708] Next, the initial luminance of the light emitting element 6, the light emitting element 7, and the light emitting element 8 is 5000 cd / m 2 The constant current drive test was carried out under the conditions of . Figure 61 The result is shown in . Figure 61 It can be seen that Light-emitting Element 7 and Light-emitting Element 8 have better reliability than Comparative Light-emitting Element 6. This is because the LUMO energy level difference between the two host materials used in the light-emitting layers of Light-emitting Element 7 and Light-emitting Element 8 is smaller than that of Comparative Light-emitting Element 6, resulting in a smaller electron injection barrier.

[0709] Example 13

[0710] This example shows the fabrication of Light-Emitting Elements 9 and 10, which are light-emitting elements according to one embodiment of the present invention. In Light-Emitting Elements 9 and 10, two host materials and one guest material are used in the light-emitting layer. Two bipolar materials are used as the host materials. The electron-accepting bipolar material (lower LUMO level) in the light-emitting layer is 2mDBTBPDBq-II, while the hole-accepting bipolar material (higher HOMO level) in the light-emitting layer is different in each element, allowing comparison of device characteristics. Figure 48Table 7 shows a schematic cross-sectional view of the light-emitting device fabricated in this example. Table 8 shows the LUMO energy difference estimated by CV measurements between the two bipolar materials used in the light-emitting layer of each device. The structures and abbreviations of the compounds used in this example can be found in the previous examples.

[0711] <Manufacturing of Light-Emitting Element>

[0712] Manufacturing of Light-Emitting Element 9

[0713] The light emitting element 9 is the same as the comparative light emitting element 1 except that the material of the light emitting layer 160 is different. Other processes are the same as those of the comparative light emitting element 1.

[0714] [Table 7]

[0715]

[0716] [Table 8]

[0717]

[0718] That is, the light-emitting layer 160 of the light-emitting element 9 is co-evaporated with 40 nm of 2mDBTBPDBq-II, 4,6mFBiP2Pm and Ir(dppm)2(acac) in a weight ratio of 0.6:0.4:0.05 (2mDBTBPDBq-II:4,6mFBiP2Pm:Ir(dppm)2(acac)).

[0719] <Manufacturing of Light-Emitting Element 10>

[0720] The light emitting element 10 is the same as the comparative light emitting element 1 except that the material of the light emitting layer 160 is different. Other processes are the same as those of the comparative light emitting element 1 .

[0721] That is, the light-emitting layer 160 of the light-emitting element 10 is co-evaporated with 40 nm of 2mDBTBPDBq-II, 4,6mFBiP2Pm and Ir(dppm)2(acac) in a weight ratio of 0.6:0.4:0.05 (2mDBTBPDBq-II:4,6mFBiP2Pm:Ir(dppm)2(acac)).

[0722] <Characteristics of Light-Emitting Element>

[0723] Next, the characteristics of the light-emitting elements 9 and 10 manufactured above were measured. The measurement method was the same as that of Example 11.

[0724] Light emitting element 9, Figure 62 The current efficiency-luminance characteristics of the light-emitting element 10 are shown. Figure 63 The brightness-voltage characteristics are shown. Figure 64 The current density-voltage characteristics are shown. Figure 65 The external quantum efficiency-brightness characteristics are shown. Figure 66 Shown at 2.5 mA / cm 2 The emission spectrum when the current density causes current to flow through light-emitting element 9 and light-emitting element 10.

[0725] In addition, Table 9 shows that 1000 cd / m 2 Element characteristics of nearby light-emitting elements 9 and 10.

[0726] [Table 9]

[0727]

[0728] like Figure 66 As shown, the peak wavelength of the electric field emission spectrum of light-emitting element 9 and light-emitting element 10 is around 579 nm, and each emits orange light with a full width at half maximum of about 67 nm.

[0729] like Figure 65 As shown in Table 9, the maximum value of the external quantum efficiency of Light-emitting Element 9 and Light-emitting Element 10 is 25% or more, and they have very high external quantum efficiency.

[0730] In addition, by Figure 63 As shown in Table 9, the light emitting element 9 and the light emitting element 10 have a brightness of about 1000 cd / m 2 The driving voltage is 2.7 V, which is a very low value. This is because the LUMO energy level difference between the two host materials used in the light-emitting layer is less than 0.5 eV and both host materials are bipolar materials.

[0731] Example 14

[0732] This example shows the fabrication of Light-Emitting Element 11 and Light-Emitting Element 12, which are light-emitting elements according to one embodiment of the present invention. In Light-Emitting Element 11 and Light-Emitting Element 12, two host materials and one guest material are used in the light-emitting layer. Two bipolar materials are used as the host materials. The electron-accepting bipolar material (lower LUMO energy level) in the light-emitting layer is 2mDBTBPDBq-II, while the hole-accepting bipolar material (higher HOMO energy level) in the light-emitting layer is different in each element, allowing comparison of device characteristics. Figure 48 Table 10 shows a schematic cross-sectional view of the light-emitting device fabricated in this example. Table 10 shows the device structure details. Table 11 also shows the LUMO energy level difference estimated by CV measurements between the two bipolar materials used in the light-emitting layer of each device. The structures and abbreviations of the compounds used in this example can be found in the previous examples.

[0733] [Table 10]

[0734]

[0735] [Table 11]

[0736]

[0737] <Manufacturing of Light-Emitting Element>

[0738] <Manufacturing of Light-Emitting Element 11>

[0739] The light emitting element 11 is the same as the comparative light emitting element 1 except that the material of the light emitting layer 160 is different. Other processes are the same as those of the comparative light emitting element 1.

[0740] That is, as the light-emitting layer 160 of the light-emitting element 11, 2mDBTBPDBq-II, 2mpFBiBPDBq and Ir(dppm)2(acac) with a weight ratio of 0.6:0.4:0.05 (2mDBTBPDBq-II:2mpFBiBPDBq:Ir(dppm)2(acac)) are first co-evaporated to a thickness of 20 nm, and then 2mDBTBPDBq-II, 2mpFBiBPDBq and Ir(dppm)2(acac) with a weight ratio of 0.8:0.2:0.05 (2mDBTBPDBq-II:2mpFBiBPDBq:Ir(dppm)2(acac)) are co-evaporated to a thickness of 20 nm.

[0741] <Manufacturing of Light-Emitting Element 12>

[0742] The light emitting element 12 is the same as the comparative light emitting element 1 except that the material of the light emitting layer 160 is different. Other processes are the same as those of the comparative light emitting element 1.

[0743] That is, as the light-emitting layer 160 of the light-emitting element 12, 2mDBTBPDBq-II, 6FL-4mpFBiBPPm and Ir(dppm)2(acac) with a weight ratio of 0.6:0.4:0.05 (2mDBTBPDBq-II:6FL-4mpFBiBPPm:Ir(dppm)2(acac)) are first co-evaporated to a thickness of 20 nm, and then 2mDBTBPDBq-II, 6FL-4mpFBiBPPm and Ir(dppm)2(acac) with a weight ratio of 0.8:0.2:0.05 (2mDBTBPDBq-II:6FL-4mpFBiBPPm:Ir(dppm)2(acac)) are co-evaporated to a thickness of 20 nm.

[0744] Next, the characteristics of the light-emitting element 11 and the light-emitting element 12 manufactured above were measured. The measurement method was the same as that of Example 11.

[0745] Light emitting element 11, Figure 67 The current efficiency-luminance characteristics of the light-emitting element 12 are shown. Figure 68 The brightness-voltage characteristics are shown. Figure 69 The current density-voltage characteristics are shown. Figure 70 The external quantum efficiency-brightness characteristics are shown. Figure 71 Shown at 2.5 mA / cm 2 The emission spectrum when the current density causes current to flow through the light-emitting element 11 and the light-emitting element 12.

[0746] In addition, Table 12 shows that 1000 cd / m 2 The device characteristics of the nearby light-emitting elements 11 and 12.

[0747] [Table 12]

[0748]

[0749] like Figure 71 As shown, the peak wavelength of the electric field emission spectrum of the light emitting element 11 and the light emitting element 12 is around 588 nm, and each emits orange light with a full width at half maximum of about 75 nm.

[0750] like Figure 70 As shown in Table 12, the maximum value of the external quantum efficiency of Light-emitting Element 11 and Light-emitting Element 12 is 31% or more, which means they have very high external quantum efficiency.

[0751] In addition, by Figure 68 As shown in Table 12, the light emitting element 11 and the light emitting element 12 have a brightness of about 1000 cd / m 2 The driving voltages at 3.0 V and 2.9 V are very low values, respectively. This is because the LUMO energy level difference between the two host materials used in the light-emitting layer is less than 0.5 eV and both host materials are bipolar materials.

[0752] <Reliability of Light-Emitting Element>

[0753] Next, the light emitting element 11 and the light emitting element 12 are set at an initial brightness of 5000 cd / m 2 The constant current drive test was carried out under the conditions of . Figure 72 The result is shown in . Figure 72 It can be seen that the time for the brightness of the light emitting element 11 and the light emitting element 12 to decrease by 10% (LT 90 ) is more than 740 hours and has good reliability. In particular, the LT of the light emitting element 12 90 It is more than 1100 hours and has very good reliability.

[0754] Example 15

[0755] This example shows an example of manufacturing Light-Emitting Element 13, which is a light-emitting element according to one embodiment of the present invention. In Light-Emitting Element 13, two host materials and one guest material are used in the light-emitting layer. Two bipolar materials are used as the host materials: 2mDBTBPDBq-II is used as the electron-accepting bipolar material (lower LUMO energy level) in the light-emitting layer, and 6FL-4PCBBiPPm is used as the hole-accepting bipolar material (higher HOMO energy level) in the light-emitting layer. Figure 48 Table 13 shows a schematic cross-sectional view of the light-emitting device fabricated in this example. Table 14 also shows the LUMO energy difference estimated by CV measurements between two bipolar materials used in the light-emitting layer of this device. The structures and abbreviations of the compounds used in this example can be found in the previous examples.

[0756] [Table 13]

[0757]

[0758] [Table 14]

[0759]

[0760] <Manufacturing of Light-Emitting Element>

[0761] 》Manufacturing of Light-Emitting Element 13》

[0762] The light emitting element 13 is the same as the comparative light emitting element 1 except that the material of the light emitting layer 160 is different. Other processes are the same as those of the comparative light emitting element 1.

[0763] That is, as the light-emitting layer 160 of the light-emitting element 13, 2mDBTBPDBq-II, 6FL-4PCBBiPPm and Ir(dppm)2(acac) with a weight ratio of 0.7:0.3:0.05 (2mDBTBPDBq-II:6FL-4PCBBiPPm:Ir(dppm)2(acac)) are first co-evaporated to a thickness of 20 nm, and then 2mDBTBPDBq-II, 6FL-4PCBBiPPm and Ir(dppm)2(acac) with a weight ratio of 0.8:0.2:0.05 (2mDBTBPDBq-II:6FL-4PCBBiPPm:Ir(dppm)2(acac)) are co-evaporated to a thickness of 20 nm.

[0764] Next, the characteristics of the light-emitting element 13 manufactured above were measured. The measurement method was the same as that of Example 11.

[0765] Figure 73 The current efficiency-luminance characteristics of the light-emitting element 13 are shown. Figure 74The brightness-voltage characteristics are shown. Figure 75 The current density-voltage characteristics are shown. Figure 76 The external quantum efficiency-brightness characteristics are shown. Figure 77 Shown at 2.5 mA / cm 2 The emission spectrum when the current density causes the current to flow through the light-emitting element 13.

[0766] In addition, 1000cd / m 2 Table 15 shows the device characteristics of the nearby light emitting device 13.

[0767] [Table 15]

[0768]

[0769] Figure 77 As shown, the peak wavelength of the electric field emission spectrum of the light emitting element 13 is 581 nm, and the full width at half maximum is 69 nm, exhibiting orange light emission.

[0770] like Figure 76 As shown in Table 15, the maximum value of the external quantum efficiency of the light-emitting element 13 is 29% or more, which is a very high external quantum efficiency.

[0771] In addition, by Figure 74 Table 15 shows that the light emitting element 13 has a power of about 1000 cd / m 2 The driving voltage at this time is a very low value of 2.8 V. This is because the LUMO energy level difference between the two host materials used in the light-emitting layer is less than 0.5 eV and both host materials are bipolar materials.

[0772] This shows that by making the LUMO energy level difference between the two host materials used in the light-emitting layer less than 0.5 eV and using bipolar materials for both host materials, the driving voltage can be reduced, the luminous efficiency can be improved, and high reliability can be achieved.

Claims

1. An organic compound represented by any one of the following structural formulas (100) to (109).

2. A light-emitting element comprising the organic compound according to claim 1.

3. An organic compound represented by the general formula (I-1): in, One of X and Y represents chlorine, and the other represents hydrogen.

Images