Light-emitting device, light-emitting apparatus, electronic device, and lighting apparatus

Abstract

To provide a highly reliable light-emitting device which efficiently transfers energy from a host material to a guest material in a light-emitting layer.SOLUTION: In a light-emitting layer of a light-emitting device, an organic compound having a specific naphthofuropyrazine skeleton is used as the host material, and a light-emitting substance (including an organometallic complex) whose T1 level satisfies a certain range is used as the guest material. Thus, the light-emitting device not only increases the efficiency of energy transfer from the host material to the guest material, but also improves the reliability.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] One embodiment of the present invention relates to a light-emitting device, a light-emitting apparatus, an electronic device, and a lighting apparatus. However, one aspect of the present invention is not limited thereto. That is, one aspect of the present invention is an object, a method, One aspect of the present invention relates to a manufacturing method, a machine, a Composition of matter. [Background technology]

[0002] A light-emitting device (also called an organic EL device or organic EL element) that consists of an EL layer sandwiched between a pair of electrodes. Electroluminescence (EL) is a It is a light-emitting device that uses a thin and lightweight LED light source, and has high-speed response to input signals. Because of their low power consumption and other characteristics, displays using these technologies are expected to become the next generation of flat panel displays. It is attracting attention as a flat panel display.

[0003] A light-emitting device emits light by applying a voltage between a pair of electrodes. The electrons and holes recombine in the EL layer, and the luminescent material (organic compound) contained in the EL layer is excited. The excited state is called the ground state, and light is emitted when the excited state returns to the ground state. In the singlet excited state (S * ) and triplet excited states (T * ) from the singlet excited state Emission from the triplet excited state is called fluorescence, and emission from the triplet excited state is called phosphorescence. The statistical generation ratio of these in S * :T * =1:3. The emission spectrum obtained from a material is specific to that material, and different types of organic compounds By using these compounds as luminescent materials, it is possible to obtain light-emitting devices with a variety of luminescent colors. Cut.

[0004] In order to improve the device characteristics and reliability of such light-emitting devices, Improvements in the structure and development of new materials have been actively pursued (see, for example, Patent Document 1). [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2017-188671 A Summary of the Invention [Problem to be solved by the invention]

[0006] In order to improve the device characteristics and reliability of light-emitting devices, Considering the mechanism of energy transfer between the host and guest materials, It is important to reduce damage caused by driving.

[0007] In one embodiment of the present invention, a host material is converted into a guest material in an emitting layer of a light-emitting device. This not only improves the efficiency of energy transfer to the material, but also provides a highly reliable light-emitting device. In one embodiment of the present invention, a host material is converted into a guest material in an emitting layer of a light-emitting device. In addition, in one embodiment of the present invention, a light-emitting device having a high energy transfer efficiency to a signal To provide a highly reliable light emitting device.

[0008] The description of these problems does not preclude the existence of other problems. It is not necessary for the embodiment to solve all of these problems. The above will become apparent from the description in the specification, drawings, claims, etc. It is possible to extract other issues from the descriptions in the patent, claims, etc. [Means for solving the problem]

[0009] One aspect of the present invention is the use of a specific naphthofuroate as a host material in the light-emitting layer of a light-emitting device. Using an organic compound with a pyrazine skeleton as a guest material, (T G ) is used to obtain a light-emitting material (including an organometallic complex) that satisfies the above requirements. This not only increases the efficiency of energy transfer to guest materials but also improves reliability. It is a light-emitting device.

[0010] One embodiment of the present invention includes an EL layer between a pair of electrodes. The EL layer includes a light-emitting layer, Organic compounds having a naphtho[2',1':4,5]furo[2,3-b]pyrazine skeleton, and a phosphorescent material, and the T1 level (T G ) is 2.5 eV or less (However, T G is derived from the absorption edge of the absorption spectrum of the phosphorescent material. This refers to the T1 level.)

[0011] Another embodiment of the present invention is a liquid crystal display device including an EL layer between a pair of electrodes, the EL layer including a light-emitting layer, The light-emitting layer is an organic compound having a naphtho[2',1':4,5]furo[2,3-b]pyrazine structure. The compounds and light-emitting devices have organometallic complexes having a diazine skeleton.

[0012] In each of the above structures, the diazine skeleton is either a pyrazine skeleton or a pyrimidine skeleton. It is preferable to have one of them.

[0013] Another embodiment of the present invention is a liquid crystal display device including an EL layer between a pair of electrodes, the EL layer including a light-emitting layer, The light-emitting layer contains a first organic compound represented by general formula (G1) and a phosphorescent material. The T1 level of a photoluminescent material (T G ) is 2.5 eV or less. (However, T G refers to the T1 level derived from the absorption edge of the absorption spectrum of the phosphorescent material.

[0014] [ka]

[0015] (In the formula, Q represents oxygen or sulfur. A represents a group having a molecular weight of 1000 or less. R 1 ~R 6 each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 7 carbon atoms, or a substituted or unsubstituted carbon and an aryl group having a prime number of 6 to 30.

[0016] In each of the above structures, the T1 level of the organic compound (T H ) and the T1 level of phosphorescent materials ( T G ) preferably satisfies the following formula (1). G is a phosphorescent material The T1 level is derived from the absorption edge of the absorption spectrum of H The phosphorescence spectrum of organic compounds This refers to the T1 level derived from the emission edge on the short wavelength side of the spectrum.)

[0017]

number

[0018] In each of the above configurations, it is more preferable that the T1 level (T H ) and phosphorescence The T1 level of a substance (T G ) preferably satisfies the following formula (2). G refers to the T1 level derived from the absorption edge of the absorption spectrum of the phosphorescent material, and T H is organic This refers to the T1 level derived from the emission edge on the short wavelength side of the phosphorescence spectrum of the compound.

[0019]

number

[0020] Note that one embodiment of the present invention is a light-emitting device including the above-described light-emitting device (also referred to as a light-emitting element). In addition, electronic devices that use light-emitting devices and light-emitting devices (specifically, light-emitting devices and Electronic equipment having a light-emitting device and a connection terminal or an operation key) and a lighting device (specifically The term also includes a lighting device having a light-emitting device or a light-emitting apparatus and a housing. Therefore, the light-emitting device in this specification is an image display device or a light source (illumination device Also, when a connector is attached to a light emitting device, such as an FPC (Flexible Print Circuit), Integrated Circuit) or TCP (Tape Carrier Packag e) is attached to the module, and the module has a printed wiring board at the end of the TCP Or, the light emitting device is mounted on an IC (integrated circuit) by the COG (Chip On Glass) method. The term "light emitting device" also includes any module in which a light emitting diode (LED) or a light emitting circuit (LCD) is directly mounted. Effect of the Invention

[0021] According to one aspect of the present invention, a light-emitting layer of a light-emitting device is provided that is capable of reacting a host material with a guest material. Not only will this improve the efficiency of energy transfer, but it will also provide highly reliable light-emitting devices. Cut.

[0022] In another embodiment of the present invention, a light-emitting device, an electronic device, and a display device each having high reliability are provided. In another embodiment of the present invention, a light-emitting device with low power consumption can be provided. An electronic device and a display device can each be provided.

[0023] The description of these effects does not preclude the existence of other effects. An embodiment does not necessarily have to have all of these effects. Effects other than these may also be included. The above is self-evident from the description, drawings, claims, etc. Other effects can be extracted from the claims and other descriptions. It is therefore possible to provide a novel light emitting device that can improve the reliability of the light emitting device. [Brief description of the drawings]

[0024] [Figure 1] 1(A) and 1(B) are diagrams showing the structure of a light-emitting device. [Diagram 2] 2(A), 2(B), and 2(C) are diagrams illustrating a light emitting device. [Diagram 3] Fig. 3(A) is a top view illustrating the light emitting device, and Fig. 3(B) is a cross-sectional view illustrating the light emitting device. [Figure 4]FIG. 4(A) is a diagram illustrating a mobile computer. FIG. 4(B) is a diagram illustrating a portable image playback device. FIG. 4(C) is a diagram illustrating a digital camera. FIG. 4(D) is a diagram illustrating a portable information terminal. FIG. 4(E) is a diagram illustrating a portable information terminal. FIG. 4(F) is a diagram illustrating a television device. FIG. 4(G) is a diagram illustrating a portable information terminal. [Diagram 5] 5(A), 5(B), and 5(C) are diagrams for explaining electronic devices. [Figure 6] 6(A) and 6(B) are diagrams for explaining an automobile. [Figure 7] 7(A) and 7(B) are diagrams illustrating the lighting device. [Figure 8] FIG. 8 is a diagram illustrating a light-emitting device. [Figure 9] FIG. 9 is a graph showing the luminance-current density characteristics of the light-emitting device 1 and the comparative light-emitting device 2. As shown in FIG. [Figure 10] FIG. 10 is a graph showing the luminance-voltage characteristics of the light-emitting device 1 and the comparative light-emitting device 2. As shown in FIG. [Figure 11] FIG. 11 is a graph showing the current efficiency-luminance characteristics of the light-emitting device 1 and the comparative light-emitting device 2. As shown in FIG. [Figure 12] FIG. 12 is a graph showing the current-voltage characteristics of the light-emitting device 1 and the comparative light-emitting device 2. As shown in FIG. [Figure 13] FIG. 13 shows the emission spectra of the light-emitting device 1 and the comparative light-emitting device 2. As shown in FIG. [Figure 14] FIG. 14 is a diagram showing the reliability of the light-emitting device 1 and the comparative light-emitting device 2. As shown in FIG. [Figure 15] FIG. 15 is a graph showing the luminance-current density characteristics of the light-emitting device 3. As shown in FIG. [Figure 16] FIG. 16 is a graph showing the luminance-voltage characteristics of the light-emitting device 3. As shown in FIG. [Figure 17] FIG. 17 is a graph showing the current efficiency-luminance characteristics of the light-emitting device 3. As shown in FIG. [Figure 18] FIG. 18 is a graph showing the current-voltage characteristics of the light-emitting device 3. As shown in FIG. [Figure 19] FIG. 19 is a graph showing the emission spectrum of the light-emitting device 3. As shown in FIG. [Figure 20] FIG. 20 is a 1H-NMR chart of 8mDBtBPNfpr(II). [Figure 21] Fig. 21(A) is a diagram showing the absorption spectrum of [Ir(dppm)2(acac)]. Fig. 21(B) is an enlarged view of the vicinity of the absorption edge of the absorption spectrum of [Ir(dppm)2(acac)]. [Figure 22] Fig. 22(A) is a diagram showing the phosphorescence spectrum of 8mDBtBPNfpr(II), and Fig. 22(B) is an enlarged view of the vicinity of the emission edge of the phosphorescence spectrum of 8mDBtBPNfpr(II). [Diagram 23] Fig. 23(A) is a diagram showing the absorption spectrum of [Ir(ppy)2(mdppy)]. Fig. 23(B) is an enlarged view of the vicinity of the absorption edge of the absorption spectrum of [Ir(ppy)2(mdppy)]. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0025] Hereinafter, embodiments of the light-emitting device of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the following description, and the scope of the present invention is not limited to the following description. The present invention can be modified in various ways in form and detail. It should not be construed as being limited to the description of the form.

[0026] In addition, the position, size, range, etc. of each component shown in the drawings are not necessarily the same as in the actual embodiment, for ease of understanding. Therefore, the disclosed invention may not necessarily represent the actual position, size, range, etc. The present invention is not necessarily limited to the position, size, range, etc. disclosed in the drawings.

[0027] In addition, in this specification and the like, when explaining the configuration of the invention using drawings, the same The reference numerals are commonly used even among different drawings.

[0028] (Embodiment 1) In this embodiment, a light-emitting device which is one embodiment of the present invention will be described with reference to FIG. The light-emitting device has a structure in which an EL layer is sandwiched between a pair of electrodes. Both have a light-emitting layer, as well as a hole injection layer, a hole transport layer, and an electron transport layer. In addition, a functional layer such as an electron injection layer may be appropriately provided.

[0029] The light-emitting layer is a layer containing a light-emitting substance (guest material) and also a host material. The light-emitting layer is made of a plurality of organic compounds that function as host materials (for example, a first organic compound and a second organic compound (or a host material and an assist material, etc.). That's fine.

[0030] Light emission from a light-emitting device occurs due to the recombination of carriers (holes and electrons) in the light-emitting layer. Energy transfer occurs from the excited state of the host material to the guest material, and the guest material The light emitting device described in this embodiment is obtained by emitting light. The material is an organic compound having a specific naphthofuropyrazine skeleton, preferably naphtho[2 We used an organic compound with a [',1':4,5]furo[2,3-b]pyrazine skeleton to As a material, a luminescent material (including organometallic complexes) whose T1 level satisfies a certain range. Preferably, the T1 level of the luminescent material is 2.5 eV or less, so that the excited state In this case, the efficiency of energy transfer from the host material to the guest material can be increased.

[0031] <Light-emitting device structure> FIG. 1 shows an example of a light-emitting device having an EL layer including a light-emitting layer between a pair of electrodes. The device has a structure in which an EL layer 103 is sandwiched between a first electrode 101 and a second electrode 102. In addition, when the first electrode 101 is used as an anode, the EL layer 103 receives holes (holes ) injection layer 111, hole transport layer 112, light emitting layer 113, electron transport layer 114, The injection layer 115 serves as a functional layer and has a structure in which the layers are laminated in sequence.

[0032] Another example of the structure of a light-emitting device is a light-emitting device formed by sandwiching a charge generating layer between a pair of electrodes. By using a structure with multiple EL layers (tandem structure), low voltage operation is possible. Light-emitting devices and micro-optical resonator (microcavity) structures formed between a pair of electrodes The present invention also includes light-emitting devices and the like having improved optical properties. When a voltage is applied between the first electrode 101 and the second electrode 102, the charge generating layer It has the function of injecting electrons into one EL layer and injecting holes into the other EL layer.

[0033] At least one of the first electrode 101 and the second electrode 102 of the light-emitting device is transparent. The electrodes have optical properties (transparent electrodes, semi-transparent / semi-reflective electrodes, etc.). In the case of a transparent electrode, the visible light transmittance of the transparent electrode is 40% or more. In the case of a semi-transmissive / semi-reflective electrode, the visible light reflectance of the semi-transmissive / semi-reflective electrode is preferably 20% or more and 80% or less. The resistivity of these electrodes is 1×10 -2 Ωcm It is preferable that:

[0034] In the above-described light-emitting device according to one embodiment of the present invention, When one of the electrodes 102 is a reflective electrode, the reflective electrode The reflectance of visible light is 40% or more and 100% or less, preferably 70% or more and 100% or less. In addition, the electrode has a resistivity of 1×10 -2 It is preferable to set it to Ωcm or less.

[0035] <First Electrode and Second Electrode> The materials for forming the first electrode 101 and the second electrode 102 are selected from those having the above-mentioned functions of both electrodes. If the requirements are met, the following materials can be used in combination. For example, metals, alloys, electrically conductive compounds, and mixtures thereof can be used appropriately. Specifically, In-Sn oxide (also called ITO), In-Si-Sn oxide (IT SO), In-Zn oxide, and In-W-Zn oxide. Aluminum (Al), Titanium (Ti), Chromium (Cr), Manganese (Mn), Iron (Fe), Cobalt (Co), Nickel (Ni), Copper (Cu), Gallium (Ga), Zinc (Zn), Indium (In), Tin (Sn), Molybdenum (Mo), Tantalum (Ta), Tungsten Tin (W), palladium (Pd), gold (Au), platinum (Pt), silver (Ag), yttrium The material used is alloys containing metals such as yttrium (Y), neodymium (Nd), and other suitable combinations. In addition, elements belonging to Group 1 or 2 of the periodic table that are not listed above may be used. Elements (e.g., lithium (Li), cesium (Cs), calcium (Ca), strontium (Sr) Rare earth metals such as strontium (Sr), europium (Eu), and ytterbium (Yb) An alloy containing these in appropriate combination, graphene, etc. may also be used.

[0036] These electrodes can be fabricated by sputtering or vacuum deposition.

[0037] <Hole injection layer> The hole injection layer 111 injects holes from the first electrode 101, which is an anode, to the EL layer 103. This layer is a layer that makes it easy to inject holes, and contains an organic acceptor material or a material with high hole injection properties. do.

[0038] The organic acceptor material is an organic compound whose LUMO level and HOMO level are close to each other. By separating charges between the organic compound and the target material, holes are generated in the organic compound. Therefore, quinodimethane derivatives and Electron-withdrawing groups such as chloranil derivatives and hexaazatriphenylene derivatives (halogen groups and silyl groups) Compounds having a 7,7,8,8-tetracyano group can be used. -2,3,5,6-Tetrafluoroquinodimethane (abbreviation: F4-TCNQ), 3,6-di Fluoro-2,5,7,7,8,8-hexacyanoquinodimethane, Chloranil, 2,3, 6,7,10,11-Hexacyano-1,4,5,8,9,12-hexaazatripheny HAT-CN, 1,3,4,5,7,8-Hexafluorotetracyano Naphthoquinodimethane (abbreviation: F6-TCNNQ), 2-(7-dicyanomethylene-1,3 ,4,5,6,8,9,10-Octafluoro-7H-pyren-2-ylidene)malononyl Trill, etc. can be used.

[0039] Among organic acceptor materials, condensed organic compounds with multiple heteroatoms such as HAT-CN are particularly Compounds in which an electron-withdrawing group is bonded to an aromatic ring are preferred because they are thermally stable. [3]Radialene derivatives with withdrawing groups (especially halogen groups such as fluoro groups and cyano groups) The α,α',α''-1,2,3-diamine is preferred because of its high electron-accepting ability. -Cyclopropanetriylidenetris[4-cyano-2,3,5,6-tetrafluorobenzyl] benzeneacetonitrile], α,α',α''-1,2,3-cyclopropanetriylidene Tris[2,6-dichloro-3,5-difluoro-4-(trifluoromethyl)benzene Acetonitrile], α,α',α''-1,2,3-cyclopropanetriylidene tris [2,3,4,5,6-pentafluorobenzeneacetonitrile] etc. can be used. Cut.

[0040] Materials with high hole injection properties include molybdenum oxide, vanadium oxide, ruthenium oxide, and Examples of the transition metal oxide include aluminum oxide, tungsten oxide, manganese oxide, etc. Other phthalocyanine (abbreviation: H2Pc) and copper phthalocyanine (abbreviation: CuPc) phthalocyanine Cyanine compounds, etc. can be used.

[0041] In addition to the above materials, we have developed a low molecular weight compound, 4,4',4''-tris(N,N-diphenylphosphine) phenylamino)triphenylamine (abbreviation: TDATA), 4,4',4''-tris[ N-(3-methylphenyl)-N-phenylamino]triphenylamine (abbreviation: MTD ATA), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamine N-[4-[N'-(3-methylphenyl) phenyl)-N'-phenylamino]phenyl}-N-phenylamino)biphenyl (abbreviation Name: DNTPD), 1,3,5-tris[N-(4-diphenylaminophenyl)-N- 3-[N-(9-phenylamino)benzene (abbreviation: DPA3B), PCzPC A1), 3,6-bis[N-(9-phenylcarbazol-3-yl)-N-phenyla Amino]-9-phenylcarbazole (abbreviation: PCzPCA2), 3-[N-(1-naphthyl -N-(9-phenylcarbazol-3-yl)amino]-9-phenylcarbazol Aromatic amine compounds such as PCzPCN1 (abbreviation: PCzPCN1) can be used.

[0042] In addition, poly(N-vinylidene) compounds, which are polymeric compounds (oligomers, dendrimers, polymers, etc.), Poly(4-vinyltriphenylamine) (abbreviation: P VTPA), poly[N-(4-{N'-[4-(4-diphenylamino)phenyl]phenyl] N-Nyl-N'-phenylamino}phenyl) methacrylamide (abbreviation: PTPDMA), Poly[N,N'-bis(4-butylphenyl)-N,N'-bis(phenyl)benzidine] ] (abbreviation: Poly-TPD), etc. can be used. PEDOT / PSS) Adding acids such as polyaniline / poly(styrene sulfonic acid) (abbreviation: PAni / PSS) Polymer compounds such as those mentioned above can also be used.

[0043] In addition, materials with high hole injection properties include hole transport materials and acceptor materials (electron acceptors). A composite material containing an acceptor material can also be used. In this case, the positive Electrons are extracted from the hole transport material, generating holes in the hole injection layer 111, and the hole transport layer 11 Holes are injected into the light-emitting layer 113 through the hole-injecting layer 111. Alternatively, the insulating layer 12 may be formed of a single layer of a composite material containing a material having a property of accepting an electron and a material having a property of accepting an electron. However, the hole transport material and the acceptor material (electron accepting material) are stacked in separate layers. It may be formed in layers.

[0044] In addition, the hole transport material is a material that has a hole transfer rate of 600 V / cm. Mobility is 1×10 -6 cm 2 A material having a hole mobility of .beta. / Vs or more is preferable. Substances other than these can be used as long as they have a higher hole transporting property than the above.

[0045] As hole transport materials, π-electron-rich heteroaromatic compounds (e.g., carbazole derivatives, Furan derivatives and aromatic amines (compounds with an aromatic amine skeleton) with high hole transport properties A material with low resistance is preferred.

[0046] The carbazole derivative (a compound having a carbazole skeleton) may be, for example, bicarbazole. azole derivatives (e.g., 3,3'-bicarbazole derivatives), aromatic compounds having a carbazolyl group aromatic amines and the like.

[0047] The bicarbazole derivative (for example, 3,3'-bicarbazole derivative) may be Specifically, 3,3'-bis(9-phenyl-9H-carbazole) (abbreviation: PCCP ), 9,9'-bis(1,1'-biphenyl-4-yl)-3,3'-bi-9H-carba 9,9'-bis(1,1'-biphenyl-3-yl)-3,3'-bi-9H-carbazol Rubazol, 9-(1,1'-biphenyl-3-yl)-9'-(1,1'-biphenyl -4-yl)-9H,9'H-3,3'-bicarbazole (abbreviation: mBPCCBP), -(2-naphthyl)-9'-phenyl-9H,9'H-3,3'-bicarbazole (abbreviation :βNCCP) etc.

[0048] Specific examples of the aromatic amine having a carbazolyl group include 4-phenyl- 4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: P CBA1BP), N-(4-biphenyl)-N-(9,9-dimethyl-9H-fluorene -2-yl)-9-phenyl-9H-carbazol-3-amine (abbreviation: PCBiF), N-(1,1'-biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazo (3-yl)phenyl]-9,9-dimethyl-9H-fluoren-2-amine (abbreviation : PCBBiF), 4,4'-diphenyl-4''-(9-phenyl-9H-carbazol PCBBi1BP), 4-(1-naphthyl)triphenylamine -4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBANB), 4,4'-di(1-naphthyl)-4''-(9-phenyl-9H-carbazone) PCBNBB, 4-phenyldiphenyl Nyl-(9-phenyl-9H-carbazol-3-yl)amine (abbreviation: PCA1BP) , N,N'-bis(9-phenylcarbazol-3-yl)-N,N'-diphenylbenzene Zene-1,3-diamine (abbreviation: PCA2B), N,N',N''-triphenyl-N, N',N''-Tris(9-phenylcarbazol-3-yl)benzene-1,3,5- Triamine (abbreviation: PCA3B), 9,9-dimethyl-N-phenyl-N-[4-(9- Phenyl-9H-carbazol-3-yl)phenyl]fluoren-2-amine (abbreviation: PCBAF), N-phenyl-N-[4-(9-phenyl-9H-carbazole-3-yl] (phenyl)phenyl)spiro-9,9'-bifluorene-2-amine (abbreviation: PCBASF), 3-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenyl Nylcarbazole (abbreviation: PCzPCA1), 3,6-bis[N-(9-phenylcarba PCz PCA2), 3-[N-(1-naphthyl)-N-(9-phenylcarbazol-3-yl )amino]-9-phenylcarbazole (abbreviation: PCzPCN1), 3-[N-(4-diphenylcarbazole phenylaminophenyl)-N-phenylamino]-9-phenylcarbazole (abbreviation: PCzDPA1), 3,6-bis[N-(4-diphenylaminophenyl)-N-phenyl 3,6-bis[N- (4-diphenylaminophenyl)-N-(1-naphthyl)amino]-9-phenylcarbamoyl PCzTPN2, 2-[N-(9-phenylcarbazol-3-yl )-N-phenylamino]spiro-9,9'-bifluorene (abbreviation: PCASF), N- [4-(9H-carbazol-9-yl)phenyl]-N-(4-phenyl)phenyla Niline (abbreviation: YGA1BP), N,N'-bis[4-(carbazol-9-yl)phenyl] N,N'-diphenyl-9,9-dimethylfluorene-2,7-diamine (abbreviation :YGA2F), 4,4',4''-tris(carbazol-9-yl)triphenyl Min (abbreviation: TCTA) and others.

[0049] Other carbazole derivatives (compounds having a carbazole skeleton) include 3-[4-( 9-Phenanthryl)-phenyl]-9-phenyl-9H-carbazole (abbreviation: PCP Pn), 3-[4-(1-naphthyl)-phenyl]-9-phenyl-9H-carbazole (abbreviation: PCPN), 1,3-bis(N-carbazolyl)benzene (abbreviation: mCP), 4 ,4'-Di(N-carbazolyl)biphenyl (abbreviation: CBP), 3,6-bis(3,5- Diphenylphenyl)-9-phenylcarbazole (abbreviation: CzTP), 1,3,5-triphenyl Tris[4-(N-carbazolyl)phenyl]benzene (abbreviation: TCPB), 9-[4-( 10-Phenyl-9-anthracenyl)phenyl]-9H-carbazole (abbreviation: CzP A) etc.

[0050] The furan derivative (a compound having a furan skeleton) specifically includes 4,4' ,4''-(benzene-1,3,5-triyl)tri(dibenzothiophene) (abbreviation: D BT3P-II), 2,8-diphenyl-4-[4-(9-phenyl-9H-fluorene -9-yl)phenyl]dibenzothiophene (abbreviation: DBTFLP-III), 4-[4 -(9-phenyl-9H-fluoren-9-yl)phenyl]-6-phenyldibenzothia Compounds with a thiophene skeleton, such as thiophene (abbreviation: DBTFLP-IV), 4,4' ,4''-(Benzene-1,3,5-triyl)tri(dibenzofuran) (abbreviation: DBF 3P-II), 4-{3-[3-(9-phenyl-9H-fluoren-9-yl)phenyl mmDBFFLBi-II, and the like.

[0051] Specific examples of the aromatic amine (a compound having an aromatic amine skeleton) include 4 ,4'-Bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB or α-NPD), N,N'-bis(3-methylphenyl)-N,N'-diphenyl- [1,1'-biphenyl]-4,4'-diamine (abbreviation: TPD), 4,4'-bis[N -(spiro-9,9'-bifluoren-2-yl)-N-phenylamino]biphenyl( Abbreviated name: BSPB), 4-phenyl-4'-(9-phenylfluoren-9-yl)trifluoroacetate 4-phenyl-3'-(9-phenylfluorene) -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-fluorene-7 -yl}phenylamine (abbreviation: DFLADFL), N-(9,9-dimethyl-2-diphenyl (phenylamino-9H-fluoren-7-yl)diphenylamine (abbreviation: DPNF), 2 -[N-(4-diphenylaminophenyl)-N-phenylamino]spiro-9,9'- Bifluorene (abbreviation: DPASF), 2,7-bis[N-(4-diphenylaminophenyl N-phenylamino]spiro-9,9'-bifluorene (abbreviation: DPA2SF) , 4,4',4''-tris[N-(1-naphthyl)-N-phenylamino]triphenyl N,N-diphenylamine (abbreviation: 1'-TNATA), 4,4',4''-tris(N,N-diphenyl amino)triphenylamine (abbreviation: TDATA), 4,4',4''-tris[N-( 3-Methylphenyl)-N-phenylamino]triphenylamine (abbreviation: m-MTDA TA), N,N'-di(p-tolyl)-N,N'-diphenyl-p-phenylenediamine (abbreviation: DTDPPA), 4,4'-bis[N-(4-diphenylaminophenyl)-N -phenylamino]biphenyl (abbreviation: DPAB), N,N'-bis{4-[bis(3- methylphenyl)amino]phenyl}-N,N'-diphenyl-(1,1'-biphenyl )-4,4'-diamine (abbreviation: DNTPD), 1,3,5-tris[N-(4-diphenyl N-phenylaminophenyl]-N-phenylamino]benzene (abbreviation: DPA3B) can be.

[0052] In addition, poly(N-vinylcarbazole) (abbreviation: PVK) is used as a hole transport material. , poly(4-vinyltriphenylamine) (abbreviation: PVTPA), poly[N-(4-{N '-[4-(4-diphenylamino)phenyl]phenyl-N'-phenylamino}phenyl N,N'-bis(4-butyl)methacrylamide] (abbreviation: PTPDMA), poly[N,N'-bis(4-butyl)methacrylamide] (abbreviation: PTPDMA), phenyl)-N,N'-bis(phenyl)benzidine (abbreviation: Poly-TPD), etc. The polymer compounds can be used.

[0053] However, the hole transport material is not limited to the above, and one or more of various known materials may be used. A combination of these may be used as the hole transport material.

[0054] The acceptor material used in the hole injection layer 111 is, for example, a 4th element in the periodic table. The oxide of a metal belonging to Groups 1 to 8 can be used. Specifically, molybdenum oxide , vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, tungsten oxide, manium oxide Among them, molybdenum oxide is particularly stable in the air. In addition, the above-mentioned organic acceptors are used. It is also possible.

[0055] The hole injection layer 111 can be formed by using various known film formation methods. For example, it can be formed by using a vacuum deposition method.

[0056] <Hole transport layer> The hole transport layer 112 transports holes injected from the first electrode 101 by the hole injection layer 111. The hole transport layer 112 is a layer that transports the electrons to the light emitting layer 113. Therefore, the hole transport layer 112 has a hole transporting layer that can be used for the hole injection layer 111. As the transport material, the above-mentioned hole transport material can be used.

[0057] In the light-emitting device according to one embodiment of the present invention, the same organic compound as that of the hole-transport layer 112 is used. The same organic compound may be used for the hole transport layer 112 and the light emitting layer 113. This allows efficient transport of holes from the hole transport layer 112 to the light emitting layer 113. can.

[0058] <Light-emitting layer> In the light-emitting device according to one embodiment of the present invention, the light-emitting layer 113 contains a light-emitting substance (guest material). A layer containing one or more organic compounds (host materials, etc.) in which a light-emitting substance is dispersed. Note that the light-emitting layer 113 in the light-emitting device according to one embodiment of the present invention contains a host As the base material, an organic compound having a specific naphthofuropyrazine skeleton (preferably naphtho[ 2',1':4,5]furo[2,3-b]pyrazine) As a thermal material, its T1 level (T G : Derived from the absorption edge of the absorption spectrum of phosphorescent materials The T1 level (T G ) is 2.5 eV Phosphorescent materials (containing a diazine skeleton (pyrazine skeleton or pyrimidine skeleton)) that satisfy the following criteria: It is particularly preferable to use an organic metal complex having the above-mentioned structure. The T1 level of the host material (T H Phosphorescence in organic compounds at the short wavelength end of the spectrum T1 level derived from the optical edge) and T1 level of the guest material (T G ) and the difference (T H -T G ) preferably satisfies the following formula (1). This is because, in order to satisfy the efficiency and lifespan requirements, The T1 level of the material (T H ) is the T1 level of the guest material (T G ) must be higher than the However, if the temperature is too high, it often impairs the life span. (Conventionally, it has been said that the higher the T1 level of the host material, the better. (Note that the aspect is different from that.) From this point of view, H -T G is 0.3 It is more preferable that the molecular weight is less than or equal to eV.

[0059]

number

[0060] Furthermore, the T1 level (T H Phosphorescence Spectra of Organic Compounds The T1 level derived from the emission edge at the short wavelength side of the TTL) and the T1 level of the guest material ( T G ) more preferably satisfies the following formula (2).

[0061]

number

[0062] In addition, by forming the light-emitting layer 113 in this manner, the energy from the host material to the guest material can be It is possible to obtain a light-emitting device with high energy transfer efficiency and high reliability.

[0063] The T1 level of the host material (T H ) is the emission edge on the short wavelength side of the phosphorescence spectrum of the host material. The value calculated from the spectrum offset is used. On the ridgeline on the short wavelength side, draw a tangent near the half-value of the peak on the shortest wavelength side, and This is the wavelength at which the horizontal axis intersects with the T1 level of the host material (T H ) can be done.

[0064] In addition, the T1 level (T G ) is the absorption edge of the absorption spectrum of the guest material. The absorption edge of the absorption spectrum is the ridge line on the longest wavelength side of the absorption spectrum. Draw a tangent at the half-value of the longest wavelength peak or shoulder peak. This is the wavelength at which the tangent line to the horizontal axis intersects with the T1 level (T G ) It is possible.

[0065] The light-emitting material (guest material) that can be used in the light-emitting layer 113 is a material that emits fluorescence. substances that emit light (fluorescent substances), substances that emit phosphorescence (phosphorescent substances), and substances that exhibit thermally activated delayed fluorescence Thermally activated delayed fluorescence Materials such as TADF (transparent emitting diode) materials and other light-emitting materials can be used. In one embodiment of the present invention, as described above, the T1 level (T G ) to a certain extent range (preferably T1 level (T G ) is 2.5 eV or less) (including organometallic complexes having a pyrazine skeleton or a pyrimidine skeleton) In addition, blue, purple, blue-purple, green, yellow-green, yellow, orange, red, and other colors are particularly preferable. A substance that emits light of a certain color can be used as appropriate. By having a light layer, a configuration that emits different luminescent colors (for example, luminescent colors that are complementary to each other) can be obtained. In addition, one light-emitting layer may be made of different light-emitting materials. A configuration having a plurality of the above may be used.

[0066] In addition, the one or more organic compounds (host materials, etc.) may include an electron transporting material and a hole transporting material. In addition to the transporting material, various carrier transporting materials such as the above-mentioned TADF materials can be used. In addition, the host material may be a hole transporting material that can be used in the hole transport layer 112. The electron transporting material may be an electron transporting material that can be used for the electron transport layer 114 described later. Specific examples of the hole transporting material and the electron transporting material are described in this specification. The above-mentioned materials or known materials can be used singly or in combination as appropriate.

[0067] Examples of fluorescent substances that can be used as guest materials in the light-emitting layer 113 include the following: Other fluorescent materials may also be used.

[0068] 5,6-Bis[4-(10-phenyl-9-anthryl)phenyl]-2,2'-bipyridine PAP2BPy, 5,6-bis[4'-(10-phenyl-9-anthracene N, N'-diphenyl-N,N'-bis[4-(9-phenyl-9H-fluoren-9-yl] )phenyl]pyrene-1,6-diamine (abbreviation: 1,6FLPAPrn), N,N'-biphenyl Bis(3-methylphenyl)-N,N'-bis[3-(9-phenyl-9H-fluorene 9-yl)phenyl]pyrene-1,6-diamine (abbreviation: 1,6mMemFLPAPrn ), N,N'-bis[4-(9H-carbazol-9-yl)phenyl]-N,N'-di Phenylstilbene-4,4'-diamine (abbreviation: YGA2S), 4-(9H-carbazo 4'-(10-phenyl-9-yl)-triphenylamine (abbreviation Name: YGAPA), 4-(9H-carbazol-9-yl)-4'-(9,10-diphenyl N,9-diphenyl-2-anthryl)triphenylamine (abbreviation: 2YGAPPA), Nyl-N-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole -3-amine (abbreviation: PCAPA), Perylene, 2,5,8,11-tetra-tert- Butylperylene (TBP), 4-(10-phenyl-9-anthryl)-4'-( 9-Phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBAP) A) N,N''-(2-tert-butylanthracene-9,10-diyldi-4,1 -phenylene)bis[N,N',N'-triphenyl-1,4-phenylenediamine]( Abbreviation: DPABPA), N,9-diphenyl-N-[4-(9,10-diphenyl-2- anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: 2PCAPPA), N-[4-(9,10-diphenyl-2-anthryl)phenyl]-N,N',N'-t N,N,N',N-triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPPA) ',N'',N'',N''',N'''-Octaphenyldibenzo[g,p]chrysene -2,7,10,15-tetraamine (abbreviation: DBC1), Coumarin 30, N-(9,1 0-Diphenyl-2-anthryl)-N,9-diphenyl-9H-carbazole-3-a 2PCAPA, N-[9,10-bis(1,1'-biphenyl-2-yl)] )-2-Anthryl]-N,9-diphenyl-9H-carbazol-3-amine (abbreviation: 2PCABPhA), N-(9,10-diphenyl-2-anthryl)-N,N',N' -Triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPA), N-[9,10 -Bis(1,1'-biphenyl-2-yl)-2-anthryl]-N,N',N'-tri Phenyl-1,4-phenylenediamine (abbreviation: 2DPABPhA), 9,10-bis( 1,1'-biphenyl-2-yl)-N-[4-(9H-carbazol-9-yl)phenyl N,N,nyl]-N-phenylanthracene-2-amine (abbreviation: 2YGABPhA), 9-Triphenylanthracene-9-amine (abbreviation: DPhAPhA), Coumarin 545 T, N,N'-Diphenylquinacridone, (abbreviation: DPQd), Rubrene, 5,12-Bi Bis(1,1'-biphenyl-4-yl)-6,11-diphenyltetracene (abbreviation: BP T), 2-(2-{2-[4-(dimethylamino)phenyl]ethenyl}-6-methyl- 4H-pyran-4-ylidene)propanedinitrile (abbreviation: DCM1), 2-{2-methyl 6-[2-(2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolidine] 4H-pyran-4-ylidene}propanedinitrile (abbreviation: DCM2), N,N,N',N'-tetrakis(4-methylphenyl)tetracene-5, 11-diamine (abbreviation: p-mPhTD), 7,14-diphenyl-N,N,N',N' -Tetrakis(4-methylphenyl)acenaphtho[1,2-a]fluoranthene-3,1 0-diamine (abbreviation: p-mPhAFD), 2-{2-isopropyl-6-[2-(1, 1,7,7-Tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij ]Quinolizin-9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitri DCJTI, 2-{2-tert-butyl-6-[2-(1,1,7,7- Tetramethyl-2,3,6,7-tetrahydro-1H,5H-benzo[ij]quinolizine -9-yl)ethenyl]-4H-pyran-4-ylidene}propanedinitrile (abbreviation: D CJTB), 2-(2,6-bis{2-[4-(dimethylamino)phenyl]ethenyl} -4H-pyran-4-ylidene)propanedinitrile (abbreviation: BisDCM), 2-{2 ,6-bis[2-(8-methoxy-1,1,7,7-tetramethyl-2,3,6,7-tetramethyl tetrahydro-1H,5H-benzo[ij]quinolizin-9-yl)ethenyl]-4H-pi {N,N'-diphenyl}propanedinitrile (abbreviation: BisDCJTM), Phenyl-N,N'-(1,6-pyrene-diyl)bis[(6-phenylbenzo[b]naphthalene 1,6BnfAPrn-03, 3, 10-Bis[N-(9-phenyl-9H-carbazol-2-yl)-N-phenylamine 3,10PCA2N bf(IV)-02), 3,10-bis[N-(dibenzofuran-3-yl)-N-phenyl 3,10F rA2Nbf(IV)-02) and others. In particular, 1,6FLPAPrn and 1,6 Pyrene diamine compounds such as mMemFLPAPrn and 1,6BnfAPrn-03 Representative condensed aromatic diamine compounds have high hole trapping properties and are highly effective in luminous efficiency and reliability. It is preferable because it is superior.

[0069] In addition, examples of phosphorescent materials that can be used as guest materials in the light-emitting layer 113 include Examples include the following:

[0070] Tris{2-[5-(2-methylphenyl)-4-(2,6-dimethylphenyl)-4H -1,2,4-triazol-3-yl-κN2]phenyl-κC}iridium(III ) (abbreviation: [Ir(mpptz-dmp)3]), tris(5-methyl-3,4-diphenyl Nyl-4H-1,2,4-triazolato)iridium(III) (abbreviation: [Ir(Mpt z)3]), tris[4-(3-biphenyl)-5-isopropyl-3-phenyl-4H -1,2,4-triazolato]iridium(III) (abbreviation: [Ir(iPrtz-3 b) Organometallic iridium complexes having a 4H-triazole skeleton, such as tris [3-methyl-1-(2-methylphenyl)-5-phenyl-1H-1,2,4-trimethyl [Ir(Mptz1-mp)3], tris(1 -Methyl-5-phenyl-3-propyl-1H-1,2,4-triazolato)iridium (III) (abbreviation: [Ir(Prptz1-Me)3]) Organometallic iridium complexes with fac-tris[(1-2,6-diisopropyl phenyl)-2-phenyl-1H-imidazole]iridium(III) (abbreviation: [Ir (iPrpmi)3]), tris[3-(2,6-dimethylphenyl)-7-methylimide Dazo[1,2-f]phenanthridinato]iridium(III) (abbreviation: [Ir(dmp and organometallic iridium complexes having an imidazole skeleton, such as impt-Me3). Bis[2-(4',6'-difluorophenyl)pyridinato-N,C 2’ ]iridium( III) Tetrakis(1-pyrazolyl)borate (abbreviation: FIr6), bis[2-(4' ,6'-Difluorophenyl)pyridinato-N,C 2’ ]Iridium(III) picolina Fluorocarbon (abbreviation: FIrpic), bis{2-[3',5'-bis(trifluoromethyl)fluorene} Phenyl]pyridinato-N,C 2’}Iridium(III) picolinate (abbreviation: [Ir( CF3ppy)2(pic)]), bis[2-(4',6'-difluorophenyl)pyri Zinat-N,C 2’ ]Iridium(III) acetylacetonate (abbreviation: FIraca c) Organometallic iridates having phenylpyridine derivatives as ligands having electron-withdrawing groups such as These are compounds that exhibit blue phosphorescence, with wavelengths ranging from 440 nm to 5 It is a compound that has an emission peak at 20 nm.

[0071] In addition, tris(4-methyl-6-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mppm)3]), tris(4-t-butyl-6-phenylpyrimidinato)yl Ir(tBuppm)3, diacetylacetonate (6-Methyl-4-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mp pm)2(acac)]), (acetylacetonato)bis(6-tert-butyl-4- Phenylpyrimidinato)iridium(III) (abbreviation: [Ir(tBuppm)2(ac ac)]), (acetylacetonato)bis[6-(2-norbornyl)-4-phenylpiperidinyl [Ir(nbppm)2(acac)]), (acetylacetonato)bis[5-methyl-6-(2-methylphenyl)-4-phenyl [Pyrimidinato]iridium(III) (abbreviation: [Ir(mpmppm)2(acac)] ), (acetylacetonato)bis(4,6-diphenylpyrimidinato)iridium(II I) (abbreviation: [Ir(dppm)2(acac)]) Metal-iridium complexes and (acetylacetonato)bis(3,5-dimethyl-2-phenyl Rupyrazinato)iridium(III) (abbreviation: [Ir(mppr-Me)2(acac) ]), (acetylacetonato)bis(5-isopropyl-3-methyl-2-phenylpyridine Dinato)iridium(III) (abbreviation: [Ir(mppr-iPr)2(acac)]) Organometallic iridium complexes with pyrazine skeletons such as tris(2-phenylpyridinium) Nat-N,C 2’) Iridium(III) (abbreviation: [Ir(ppy)3]), bis(2- Phenylpyridinato-N,C 2’ ) Iridium(III) acetylacetonate (abbreviation: [Ir(ppy)2(acac)]), bis(benzo[h]quinolinato)iridium (I II) Acetylacetonate (abbreviation: [Ir(bzq)2(acac)]), tris(beta Tris[h]quinolinato)iridium(III) (abbreviation: [Ir(bzq)3]) (2-phenylquinolinato-N,C 2’ ) Iridium(III) (abbreviation: [Ir(pq) 3]), bis(2-phenylquinolinato-N,C 2’ ) Iridium(III) acetylated A compound with a pyridine skeleton, such as setonate (abbreviation: [Ir(pq)2(acac)]) In addition to the organometallic iridium complexes, tris(acetylacetonato)(monophenanthroline)tetraacetate Rare earth metals such as rubium(III) (abbreviation: [Tb(acac)3(Phen)]) These are mainly compounds that exhibit green phosphorescence and have wavelengths between 500 nm and 60 The emission peak is at 10 nm. is particularly preferred because it is remarkably excellent in reliability and luminous efficiency.

[0072] Also, (diisobutyrylmethanato)bis[4,6-bis(3-methylphenyl)pyrimidinyl] Nat[Iridium(III) (abbreviation: [Ir(5mdppm)2(dibm)]), bis [4,6-Bis(3-methylphenyl)pyrimidinato](dipivaloylmethanato)irid Ir(III) (abbreviation: [Ir(5mdppm)2(dpm)]), bis[4,6-di( Naphthalen-1-yl)pyrimidinato](dipivaloylmethanato)iridium(III) (abbreviation: [Ir(d1npm)2(dpm)]) iridium complexes of the genus acetylacetonato, bis(2,3,5-triphenylpyrazine) Iridium(III) (abbreviation: [Ir(tppr)2(acac)]), bis(2, 3,5-Triphenylpyrazinato)(dipivaloylmethanato)iridium(III)(abbreviation Name: [Ir(tppr)2(dpm)]), (acetylacetonato)bis[2,3-bis (4-fluorophenyl)quinoxalinato]iridium(III) (abbreviation: [Ir(Fd pq)2(acac)]) and other organometallic iridium complexes with pyrazine skeletons, Tris(1-phenylisoquinolinato-N,C 2’ ) Iridium(III) (abbreviation: [Ir (piq)3]), bis(1-phenylisoquinolinato-N,C 2’ ) Iridium (II I) Pyridyl acetylacetonate (abbreviation: [Ir(piq)2(acac)]) In addition to organometallic iridium complexes with iridium skeletons, 2,3,7,8,12,13,17,18 -Octaethyl-21H,23H-porphyrin platinum(II) (abbreviation: PtOEP) Platinum complexes such as tris(1,3-diphenyl-1,3-propanedionato) (monophenyl Anthroline) europium(III) (abbreviation: [Eu(DBM)3(Phen)]), Tris[1-(2-thenoyl)-3,3,3-trifluoroacetonato](monophenanthate Europium(III) (abbreviation: [Eu(TTA)3(Phen)]) These are compounds that exhibit red phosphorescence and have a wavelength of 600 nm. The emission peak is between 700 nm and 700 nm. The di-nium complex can emit red light with good chromaticity.

[0073] In addition to the above, known phosphorescent materials can also be used.

[0074] In addition, examples of TADF materials that can be used as guest materials for the light-emitting layer 113 include Examples include the following:

[0075] Use of fullerene and its derivatives, acridine and its derivatives, eosin derivatives, etc. In addition, magnesium (Mg), zinc (Zn), cadmium (Cd), tin (Sn ), platinum (Pt), indium (In), or palladium (Pd) Examples of the metal-containing porphyrin include those represented by the following structural formula: The protoporphyrin-tin fluoride complex (SnF2(Proto IX)) shown in Fig. Porphyrin-Tin Fluoride Complex (SnF2(Meso IX)), Hematoporphyrin- Tin fluoride complex (SnF2(Hemato IX)), coproporphyrin tetramethyl Ester-Tin Fluoride Complex (SnF2(Copro III-4Me)), Octaethyl Porphyrin-tin fluoride complex (SnF2(OEP)), etioporphyrin-tin fluoride SnF2(Etio I) complex, octaethylporphyrin-platinum chloride complex (Pt Cl2OEP) and the like.

[0076] [ka]

[0077] In addition, as shown in the structural formula below, 2-(biphenyl-4-yl)-4,6-bis (12-phenylindolo[2,3-a]carbazol-11-yl)-1,3,5-trimethylphenyl Triazine (abbreviation: PIC-TRZ), 2-{4-[3-(N-phenyl-9H-carbazo 4,6-diphenyl- 1,3,5-Triazine (abbreviation: PCCzPTzn), 2-[4-(10H-phenoxazine Diphenyl-4,6-diphenyl-1,3,5-triazine (abbreviation: PXZ-TRZ), 3-[4-(5-phenyl-5,10-dihydrophenazine-10- 4,5-diphenyl-1,2,4-triazole (abbreviation: PPZ-3 TPT), 3-(9,9-dimethyl-9H-acridin-10-yl)-9H-xanthene ACRXTN, bis[4-(9,9-dimethyl-9,10-dihydro- DMAC-DPS, 10-phenyl-1 0H,10'H-spiro[acridine-9,9'-anthracene]-10'-one (abbreviation :ACRSA), 4-(9'-phenyl-3,3'-bi-9H-carbazol-9-yl ) benzofuro[3,2-d]pyrimidine (abbreviation: 4PCCzBfpm), 4-[4-(9 '-Phenyl-3,3'-bi-9H-carbazol-9-yl)phenyl]benzofuro[ 3,2-d]pyrimidine (abbreviation: 4PCCzPBfpm), 9-[3-(4,6-diphenyl Nyl-1,3,5-triazin-2-yl)phenyl]-9'-phenyl-2,3'-biphenyl -9H-carbazole (abbreviation: mPCCzPTzn-02) and other π-electron rich heteroaromatic rings Also usable are heterocyclic compounds having a π-electron deficient heteroaromatic ring.

[0078] [ka]

[0079] Since the heterocyclic compound has a π-electron rich heteroaromatic ring and a π-electron deficient heteroaromatic ring, The electron transporting property and the hole transporting property are both high, and thus the compound is preferable. Among the skeletons that can be used, the pyridine skeleton, the diazine skeleton (pyrimidine skeleton, pyrazine skeleton, pyrida skeleton) The benzene skeleton) and the triazine skeleton are preferred because they are stable and reliable. Zofuropyrimidine skeleton, benzothienopyrimidine skeleton, benzofuropyrazine skeleton, benzo A thienopyrazine skeleton is preferred because it has high acceptor properties and good reliability.

[0080] Among the skeletons having a π-electron-rich heteroaromatic ring, acridine skeleton, phenoxazine skeleton, The skeleton, phenothiazine skeleton, furan skeleton, thiophene skeleton, and pyrrole skeleton are stable. It is preferable to have at least one of the furan skeletons because of its high reliability. The dibenzofuran skeleton is the most common, and the dibenzothiophene skeleton is the most common. The pyrrole skeleton is preferably an indole skeleton, a carbazole skeleton, or Indolocarbazole skeleton, bicarbazole skeleton, 3-(9-phenyl-9H-carbazo A 9H-carbazole skeleton is particularly preferred.

[0081] In addition, a substance in which a π-electron rich heteroaromatic ring and a π-electron deficient heteroaromatic ring are directly bonded is The electron donating ability of the π-electron rich heteroaromatic ring and the electron accepting ability of the π-electron deficient heteroaromatic ring are both strong. Since the energy difference between the S1 and T1 levels becomes small, thermally activated delayed fluorescence can be obtained efficiently. In addition, a heteroaromatic ring such as a cyano group is particularly preferred instead of the π-electron deficient heteroaromatic ring. An aromatic ring having such an electron-withdrawing group bonded thereto may be used. Aromatic amine skeletons, phenazine skeletons, etc. can be used. , xanthene skeleton, thioxanthene dioxide skeleton, oxadiazole skeleton, triazo borane skeleton, imidazole skeleton, anthraquinone skeleton, phenylborane, boranthrene, etc. Boron-containing skeleton, nitrile group such as benzonitrile or cyanobenzene, or cyano group Aromatic and heteroaromatic rings, carbonyl skeletons such as benzophenone, and phosphine oxide skeletons , sulfone skeleton, etc. can be used.

[0082] In this way, at least one of a π-electron deficient heteroaromatic ring and a π-electron rich heteroaromatic ring Alternatively, π-electron deficient and π-electron rich backbones can be used.

[0083] In addition, TADF materials have a small difference between the S1 and T1 levels, and can be triple-phased by reverse intersystem crossing. The function of converting energy from first excitation energy to singlet excitation energy Therefore, the triplet excitation energy can be converted to a single state by a small amount of thermal energy. It is possible to upconvert to singlet excited energy (reverse intersystem crossing), and efficiently convert singlet excited states It is possible to generate triplet excitation energy and convert it into luminescence. .

[0084] In addition, exciplexes (complexes) that form excited states with two types of substances The difference between the S1 and T1 levels is extremely small. As a TADF material capable of converting triplet excitation energy into singlet excitation energy, It has all the functions.

[0085] In addition, as an index of the T1 level at this time, The phosphorescence spectrum can be used. For TADF materials, the short wavelength side of the fluorescence spectrum is Draw a tangent at the tail of the line, and define the energy of the wavelength of the extrapolated line as the S1 level. A tangent line was drawn at the base of the short wavelength side of the curve, and the energy of the wavelength of the extrapolated line was set as the T1 level. In this case, the difference between S1 and T1 is preferably 0.3 eV or less, and more preferably 0.2 eV or less. It is even more preferable that

[0086] In addition, when a TADF material is used as the guest material of the light-emitting layer 113, the host material S1 The S1 level of the TADF material is preferably higher than the S1 level of the host material. It is preferably higher than the T1 level of the ADF material.

[0087] The host material of the light-emitting layer 113 may be a hole-transporting material or an electron-transporting material as shown below. In one embodiment of the present invention, a host material can be used as needed. A specific naphthofuropyrazine skeleton (naphtho[2',1':4,5]furo[2,3-b]pyra A luminescent material having a T1 level of 2.5 eV or less using an organic compound having a silyl skeleton. Using organometallic complexes with a diazine skeleton (including a pyrazine skeleton or pyrimidine skeleton) It is preferable to form the light-emitting layer 113 using a naphthofuropyrazine skeleton. The to[2',1':4,5]furo[2,3-b]pyrazine structure has a high T1 of over 2.5 eV. Since the T1 level is 2.5 eV or less, the excitation energy of T1 is It is possible to move without being deactivated. In addition, among naphthofuropyrazine structures, In particular, the naphtho[2',1':4,5]furo[2,3-b]pyrazine structure has been Organometallic compounds with a diazine skeleton (including a pyrazine skeleton or pyrimidine skeleton) The overlap with the MLCT absorption band of the complex is large, and the efficiency of energy transfer is optimal. The stable excitation of the complex improves the durability of the light-emitting device, resulting in a highly reliable light-emitting device. You can get a chair.

[0088] In addition, the above naphthofuropyrazine structure (naphtho[2',1':4,5]furo[2,3-b As the organic compound having a pyrazine skeleton, an organic compound represented by the following general formula (G1) is Things can be used.

[0089] [ka]

[0090] (In the formula, Q represents oxygen or sulfur. A represents a group having a molecular weight of 1000 or less. R 1 ~ R 6 each independently represents a hydrogen atom, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, or an unsubstituted cycloalkyl group having 3 to 7 carbon atoms, or a substituted or unsubstituted carbon aryl groups having 6 to 30 carbon atoms.

[0091] Specific examples of the alkyl group having 1 to 6 carbon atoms in the above general formula (G1) include methyl, butyl, sec-butyl, isobutyl butyl, pentyl, isopentyl, sec-pentyl, tert t-Pentyl, neopentyl, hexyl, isohexyl, 3-methylpentyl , 2-methylpentyl group, 2-ethylbutyl group, 1,2-dimethylbutyl group, 2,3-di Examples include a methylbutyl group and an n-heptyl group.

[0092] Specific examples of the cycloalkyl group having 3 to 7 carbon atoms in the above general formula (G1) include , cyclopropyl group, cyclobutyl group, cyclopentyl group, cyclohexyl group, 1-methyl cyclohexyl group, 2,6-dimethylcyclohexyl group, cycloheptyl group, cyclooctyl group, Examples thereof include an octyl group.

[0093] Specific examples of the aryl group having 6 to 30 carbon atoms in the above general formula (G1) include Phenyl group, o-tolyl group, m-tolyl group, p-tolyl group, mesityl group, o-biphenyl group , m-biphenyl group, p-biphenyl group, 1-naphthyl group, 2-naphthyl group, fluorenyl group fluorenyl group, 9,9-dimethylfluorenyl group, spirofluorenyl group, phenanthrenyl group, Examples thereof include anthracenyl groups and fluoranthenyl groups.

[0094] In addition, the above structure (naphthofuropyrazine skeleton (naphtho[2',1':4,5]furo[2, 3-b] Pyrazine skeleton) is used as a host material, and the T1 level is 2.5 eV or less, and is a compound having a diazine skeleton (including a pyrazine skeleton or a pyrimidine skeleton). In the light-emitting layer 113 having a structure in which an organic metal complex is used as a light-emitting material, The difference between the T1 level of an organic compound and the T1 level of a light-emitting substance (guest material) is 0.2 eV. It is preferable that the n-type ... The to[2',1':4,5]furo[2,3-b]pyrazine structure has a high T1 of over 2.5 eV. Since the T1 level is 2.5 eV or less, the excitation energy of T1 is It is possible to move without being deactivated. In addition, among naphthofuropyrazine structures, In particular, the naphtho[2',1':4,5]furo[2,3-b]pyrazine skeleton is a diazine skeleton (pyrazine The overlap with the MLCT absorption band of organometallic complexes having a rhodidine or pyrimidine skeleton The large difference in the energy transfer efficiency is optimal, and these complexes are excited stably. This improves the durability of the light-emitting device and provides high reliability. The organometallic complex having a radicandine or pyrimidine skeleton is used as a light-emitting material. In the light-emitting layer 113 having the above structure, the T1 level of the organic compound which is the host material and the T2 level of the light-emitting material The difference between the T1 level of the guest material and the T1 level of the These complexes are more stably excited under low temperatures, leading to the realization of more durable light-emitting devices. It can be realized.

[0095] Specific examples of the organic compound represented by the general formula (G1) are shown in the following structural formulas (100) to (103). The formula is shown in (123).

[0096] [ka]

[0097] [ka]

[0098] [ka]

[0099] Other examples of hole transporting materials that can be used as the host material of the light emitting layer 113 include: The hole mobility at a square root of the electric field strength [V / cm] of 600 is 1×10 -6 cm 2 / Vs Substances having the above hole mobility are preferred, and examples thereof include the following:

[0100] 4,4'-Bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NP B) N,N'-bis(3-methylphenyl)-N,N'-diphenyl-[1,1'-biphenyl] phenyl]-4,4'-diamine (abbreviation: TPD), 4,4'-bis[N-(spiro-9 ,9'-Bifluoren-2-yl)-N-phenylamino]biphenyl (abbreviation: BSPB ), 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine ( Abbreviated name: BPAFLP), 4-phenyl-3'-(9-phenylfluoren-9-yl) tetrahydrofuran mBPAFLP, 4-phenyl-4'-(9-phenyl-9 H-Carbazol-3-yl)triphenylamine (abbreviation: PCBA1BP), 4,4' -Diphenyl-4''-(9-phenyl-9H-carbazol-3-yl)triphenyl Amine (abbreviation: PCBBi1BP), 4-(1-naphthyl)-4'-(9-phenyl-9 H-Carbazol-3-yl)triphenylamine (abbreviation: PCBANB), 4,4'- Di(1-naphthyl)-4''-(9-phenyl-9H-carbazol-3-yl)triphenylphosphine PCBNBB, 9,9-dimethyl-N-phenyl-N-[4-( 9-phenyl-9H-carbazol-3-yl)phenyl]fluoren-2-amine (abbreviation Name: PCBAF), N-phenyl-N-[4-(9-phenyl-9H-carbazole-3 -yl)phenyl]spiro-9,9'-bifluorene-2-amine (abbreviation: PCBASF ), and 1,3-bis(N-carbazolyl)benzene mCP, 4,4'-di(N-carbazolyl)biphenyl (CBP), 3,6-Bis(3,5-diphenylphenyl)-9-phenylcarbazole (abbreviation: Cz TP), 3,3'-bis(9-phenyl-9H-carbazole) (abbreviation: PCCP), etc. Compounds with a carbazole skeleton such as 4,4',4''-(benzene-1,3,5-triphenylphosphine) 2,8-diphenyl)tri(dibenzothiophene) (abbreviation: DBT3P-II) -4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]dibenzothiophene Fluorene (abbreviation: DBTFLP-III), 4-[4-(9-phenyl-9H-fluorene- 9-yl)phenyl]-6-phenyldibenzothiophene (abbreviation: DBTFLP-IV) Compounds with thiophene skeletons such as 4,4',4''-(benzene-1,3,5- triyl)tri(dibenzofuran) (abbreviation: DBF3P-II), 4-{3-[3-(9 -phenyl-9H-fluoren-9-yl)phenyl]phenyl}dibenzofuran (abbreviation :mmDBFFLBi-II) and other compounds having a furan skeleton. Among them, compounds with aromatic amine skeletons and compounds with carbazole skeletons have high reliability. In addition, the hole transport property is high, and this contributes to reducing the driving voltage, which is preferable. The organic compounds given as examples of the second organic compound above can also be used.

[0101] In addition, as an electron transport material, the electron transfer rate at the square root of the electric field strength [V / cm] of 600 is Mobility is 1×10 -6 cm 2 A substance having an electron mobility of 0.1 V or more is preferred. For example, The following electron transporting materials are used in the electron transport layer described later. It can also be used for 114.

[0102] A specific example of an electron transport material is bis(10-hydroxybenzo[h]quinolinato)benzamide. Lithium(II) (abbreviation: BeBq2), tris(8-quinolinolato)aluminum(I II) (abbreviation: Alq3), tris(4-methyl-8-quinolinolato)aluminum (abbreviation Name: Almq3), Bis(2-methyl-8-quinolinolato)(4-phenylphenolato) Aluminum(III) (abbreviation: BAlq), bis(8-quinolinolato)zinc(II) ( abbreviation: Znq), bis[2-(2-benzoxazolyl)phenolato]zinc(II) (abbreviation Name: ZnPBO), bis[2-(2-benzothiazolyl)phenolato]zinc(II) (abbreviation Examples of metal complexes include ZnBTZ.

[0103] Another specific example of the electron transport material is 2-(4-biphenylyl)-5-(4-t ert-butylphenyl)-1,3,4-oxadiazole (abbreviation: PBD), 3-(4 -biphenylyl)-4-phenyl-5-(4-tert-butylphenyl)-1,2,4 -Triazole (abbreviation: TAZ), 1,3-bis[5-(p-tert-butylphenyl )-1,3,4-Oxadiazol-2-yl]benzene (abbreviation: OXD-7), 9-[ 4-(5-phenyl-1,3,4-oxadiazol-2-yl)phenyl]-9H-ca Rubazol (abbreviation: CO11), 2,2',2''-(1,3,5-benzenetriyl) Tris(1-phenyl-1H-benzimidazole) (abbreviation: TPBI), 2-[3-( Dibenzothiophene-4-yl)phenyl]-1-phenyl-1H-benzimidazole (abbreviation: mDBTBIm-II) and other heterocyclic compounds having a polyazole skeleton. can be.

[0104] Another specific example of the electron transport material is 2-[3-(dibenzothiophene-4-yl) 2mDBTPDBq-II 2-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[f, h]quinoxaline (abbreviation: 2mDBTBPDBq-II), 2-[3'-(9H-carba 2-(2-phenyl-9-yl)biphenyl-3-yl]dibenzo[f,h]quinoxaline (abbreviation: mCzBPDBq), dibenzoquinoxaline derivatives such as 4,6-bis[3-(phenanthracene 4,6-biphenyl]pyrimidine (abbreviation: 4,6mPnP2Pm), 4,6mDBTP2P m-II), 4-[3-(dibenzothiophen-4-yl)phenyl]-8-(naphthalene 8βN-4mDB tPBfpm), 4,8-bis[3-(dibenzothiophen-4-yl)phenyl]-[ 1]Benzofuro[3,2-d]pyrimidine (abbreviation: 4,8mDBtP2Bfpm), 8- [3'-(dibenzothiophen-4-yl)(1,1'-biphenyl-3-yl)]naphthalene To[1',2':4,5]furo[3,2-d]pyrimidine (abbreviation: 8mDBtBPNfp m), 8-[(2,2'-binaphthalene)-6-yl]-4-[3-(dibenzothiophene 8(βN-4-yl)phenyl-[1]benzofuro[3,2-d]pyrimidine 2)-4mDBtPBfpm) and other pyrimidine derivatives, 3,8-bis[3-(dibenzo Thiophen-4-yl)phenyl]benzofuro[2,3-b]pyrazine (abbreviation: 3,8m DBtP2Bfpr), 9-[(3'-dibenzothiophen-4-yl)biphenyl-3 -yl]naphtho[1',2':4,5]furo[2,3-b]pyrazine (abbreviation: 9mDBt BPNfpr), 8-[(3'-dibenzothiophen-4-yl)biphenyl-3-yl ]naphtho[2',1':4,5]furo[2,3-b]pyrazine (abbreviation: 8mDBtBPN fpr(II)), 12-[(3'-dibenzothiophen-4-yl)biphenyl-3- 12-yl]phenanthro[9',10':4,5]furo[2,3-b]pyrazine (abbreviation: pyrazine derivatives such as mDBtBPPnfpr, etc., Examples include:

[0105] Another specific example of the electron transport material is 3,5-bis[3-(9H-carbazole -9-yl)phenyl]pyridine (abbreviation: 35DCzPPy), 1,3,5-tri[3- (3-pyridyl)phenyl]benzene (abbreviation: TmPyPB) and other compounds with pyridine skeletons Examples of the heterocyclic compounds include

[0106] Among the above, heterocyclic compounds having a diazine skeleton and heterocyclic compounds having a pyridine skeleton are preferred. The material has good reliability and is preferable. In particular, the material has a diazine (pyrimidine or pyrazine) skeleton. The heterocyclic compound has a high electron transporting property and contributes to reducing the driving voltage.

[0107] In addition, the above-mentioned TADF material can also be used as the host material of the light-emitting layer 113. In addition, when a TADF material is used as a host material, the triplet excitation generated in the TADF material The energy is converted to singlet excitation energy by reverse intersystem crossing and further to luminescence centers. By transferring energy to the material, the light-emitting efficiency of the light-emitting device can be increased. The TADF material acts as an energy donor, and the luminescent center acts as an energy acceptor. Therefore, using a TADF material as a host material is This is effective when a fluorescent material is used as the light source. In order to achieve this, the S1 level of the TADF material is preferably higher than the S1 level of the fluorescent material. In addition, the T1 level of the TADF material is preferably higher than the S1 level of the fluorescent emitting material. Therefore, the T1 level of the TADF material is preferably higher than the T1 level of the fluorescent emitting material. stomach.

[0108] In addition to the above organic compounds, the following organic compounds can be used in the light-emitting layer 113: From the viewpoint that it is preferable to combine it with a luminescent substance (fluorescent substance, phosphorescent substance) The organic compounds shown below (some overlap with the above) are included.

[0109] When the luminescent material is a fluorescent luminescent material, the organic compound preferably used in combination with the fluorescent luminescent material Examples include anthracene derivatives, tetracene derivatives, phenanthrene derivatives, and pyrene derivatives. These include condensed polycyclic aromatic compounds such as chrysene derivatives, dibenzo[g,p]chrysene derivatives, etc. Can be obtained.

[0110] A specific example of an organic compound that is preferably combined with a fluorescent substance is 9-phenyl 3-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole ( Abbreviation: PCzPA), 3,6-diphenyl-9-[4-(10-phenyl-9-anthracene 3-[4-(1-naphthyl)phenyl]-9H-carbazole (abbreviation: DPCzPA), PCPN, 9,10- Diphenylanthracene (abbreviation: DPAnth), N,N-diphenyl-9-[4-(1 0-Phenyl-9-anthryl)phenyl]-9H-carbazol-3-amine (abbreviation: CzA1PA), 4-(10-phenyl-9-anthryl)triphenylamine (abbreviation: DPhPA), YGAPA, PCAPA, N,9-diphenyl-N-{4-[4-(10 -Phenyl-9-anthryl)phenyl]phenyl}-9H-carbazol-3-amine (abbreviation: PCAPBA), N-(9,10-diphenyl-2-anthryl)-N,9-di Phenyl-9H-carbazol-3-amine (abbreviation: 2PCAPA), 6,12-dimeth Oxy-5,11-diphenylchrysene, N,N,N',N',N'',N'',N''' ,N'''-Octaphenyldibenzo[g,p]chrysene-2,7,10,15-tetra Amine (abbreviation: DBC1), 9-[4-(10-phenyl-9-anthracenyl)phenyl 7-[4-(10-phenyl-9-anthylene]-9H-carbazole (abbreviation: CzPA), tolyl)phenyl]-7H-dibenzo[c,g]carbazole (abbreviation: cgDBCzPA ), 6-[3-(9,10-diphenyl-2-anthryl)phenyl]-benzo[b]na 2mBnfPPA, 9-phenyl-10-{4-( 9-Phenyl-9H-fluoren-9-yl)-biphenyl-4'-yl}-anthracene (abbreviation: FLPPA), 9,10-bis(3,5-diphenylphenyl)anthracene (abbreviation: DPPA), 9,10-di(2-naphthyl)anthracene (abbreviation: DNA), 2 -tert-Butyl-9,10-di(2-naphthyl)anthracene (abbreviation: t-BuDN A), 9,9'-bianthryl (abbreviation: BANT), 9,9'-(stilbene-3,3' -diyl)diphenanthrene (abbreviation: DPNS), 9,9'-(stilbene-4,4'- Diphenyl)phenanthrene (abbreviation: DPNS2), 1,3,5-tri(1-pyrenyl)be benzene (abbreviation: TPB3), 5,12-diphenyltetracene, 5,12-bis(biphenyl) nyl-2-yl)tetracene and the like.

[0111] In addition, when the luminescent material is a phosphorescent material, a combination with the phosphorescent material is preferable. The compound is the triplet excitation energy (energy between the ground state and the triplet excited state) of the luminescent material. It is necessary to select an organic compound with triplet excitation energy larger than the energy difference between the excited states. A plurality of organic compounds (e.g., a first host material and a second host material) are mixed together to form an oxidative complex. A light-emitting material is used in combination with a light-emitting material. In this case, it is preferable to use a mixture of these organic compounds with a phosphorescent material. .

[0112] With this structure, the energy transfer from the exciplex to the luminescent material, Ex Using TET (Exciplex-Triplet Energy Transfer) In addition, the combination of multiple organic compounds can be used as the excitation light source. Compounds that easily form electron-emitting complexes and easily accept holes (hole transport materials) are preferred. It is particularly preferable to combine it with a compound that easily accepts electrons (electron transporting material).

[0113] In addition, when the light-emitting substance is a phosphorescent light-emitting substance, a combination with the phosphorescent light-emitting substance is preferably Compounds (host materials, assist materials) include aromatic amines, carbazole derivatives, diphenyl ethers, and Benzothiophene derivatives, dibenzofuran derivatives, zinc and aluminum metal complexes, Quinoxadiazole derivatives, triazole derivatives, benzimidazole derivatives, quinoxaline Derivatives, dibenzoquinoxaline derivatives, pyrimidine derivatives, pyrazine derivatives, triazines derivatives, pyridine derivatives, bipyridine derivatives, phenanthroline derivatives, etc. .

[0114] Specific examples of these include 2-(4-biphenylyl)-5-(4-tert-butyl) phenyl)-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-oxadiazole-2 -yl)phenyl]-9H-carbazole (abbreviation: CO11), 3-(4-biphenylyl) )-4-Phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (Abbreviation: TAZ), 3-(4-tert-butylphenyl)-4-(4-ethylphenyl )-5-(4-biphenylyl)-1,2,4-triazole (abbreviation: p-EtTAZ), etc. The triazole derivative, 2,2',2''-(1,3,5-benzenetriyl)tris( 1-phenyl-1H-benzimidazole) (abbreviation: TPBI), 2-[3-(dibenzo Thiophen-4-yl)phenyl]-1-phenyl-1H-benzimidazole (abbreviation: mDBTBIm-II), 4,4'-bis(5-methylbenzoxazol-2-yl) Stilbene (abbreviation: BzOs), bathophenanthroline (abbreviation: Bphen), bathocu Proine (abbreviation: BCP), 2,9-bis(naphthalene-2-yl)-4,7-diphenyl 1,10-phenanthroline (abbreviation: NBphen), 2-[3-(dibenzothiophene 2m-phenyl-4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTPDB q-II), 2-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]di Benzo[f,h]quinoxaline (abbreviation: 2mDBTBPDBq-II), 2-[3'-( 9H-carbazol-9-yl)biphenyl-3-yl]dibenzo[f,h]quinoxalate 2mCzBPDBq, 2-[4-(3,6-diphenyl-9H-carbazolyl] 2CzPDBq-I II), 7-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]ky Noxalin (abbreviation: 7mDBTPDBq-II) and 6-[3-(dibenzothiophene -4-yl)phenyl]dibenzo[f,h]quinoxaline (abbreviation: 6mDBTPDBq- II) and other quinoxaline derivatives, or dibenzoquinoxaline derivatives.

[0115] Furthermore, 4,6-bis[3-(phenanthren-9-yl)phenyl]pyrimidine (abbreviation : 4,6mPnP2Pm), 4,6-bis[3-(4-dibenzothienyl)phenyl]pi Rimidine (abbreviation: 4,6mDBTP2Pm-II), 4,6-bis[3-(9H-carba pyrimidine (abbreviation: 4,6mCzP2Pm) Derivatives of 2-{4-[3-(N-phenyl-9H-carbazol-3-yl)-9H- Carbazol-9-yl]phenyl}-4,6-diphenyl-1,3,5-triazine ( Abbreviation: PCCzPTzn), 9-[3-(4,6-diphenyl-1,3,5-triazine -2-yl)phenyl]-9'-phenyl-2,3'-bi-9H-carbazole (abbreviation: mPCCzPTzn-02) and other triazine derivatives, 3,5-bis[3-(9H-carba 35DCzPPy, 1,3,5-Triphenylpyridine (abbreviation: 35DCzPPy), Pyridine derivatives such as [3-(3-pyridyl)phenyl]benzene (abbreviation: TmPyPB) , etc.

[0116] In addition, poly(2,5-pyridinediyl) (abbreviation: PPy), poly[(9,9-dihexyl Fluorene-2,7-diyl)-co-(pyridine-3,5-diyl)] (abbreviation: PF- Py), poly[(9,9-dioctylfluorene-2,7-diyl)-co-(2,2' -bipyridine-6,6'-diyl) (abbreviation: PF-BPy) You can also be there.

[0117] The above materials may be used in combination with low molecular weight materials or high molecular weight materials. For this purpose, known methods (such as vacuum deposition, coating, and printing) can be appropriately used.

[0118] <Electron transport layer> The electron transport layer 114 is a layer that transports electrons injected from the second electrode 102 to the light emitting layer 113. In addition, between the electron transport layer 114 and the second electrode 102, an electron injection layer 1 The electron transport layer 114 may include an electron transport material. In addition to the conductive material, the material contains either a metal, a metal salt, a metal oxide, or a metal complex. In particular, it is preferable to use a metal complex having an alkali metal or an alkaline earth metal. In addition, when these metals, metal salts, metal oxides, or metal complexes are contained, the electron transport For example, the electron transport layer 114 may be formed in a laminate structure. In the case where the light-emitting layer 113 is in contact with the light-emitting layer 113, the light-emitting layer 113 may be in contact with the light-emitting layer 113. The electron transport layer 114 (in the case of a laminated structure, the layer in contact with the light-emitting layer) is used. The LUMO level of the electron transporting material is lower than the LUMO level of the host material used in the light-emitting layer 113. The difference is 0.15 eV or more and 0.40 eV or less, or The value is preferably 0.20 eV or more and 0.40 eV or less, and more preferably 0.20 eV or more and 0.35 eV or less. This is more preferable.

[0119] The electron transporting material used in the electron transport layer 114 is an electron transport material having a HOMO level of −6.0 eV or higher. The electron transport material having a HOMO level of -6.0 eV or more is preferably an electric field The electron mobility at a square root of 600 V / cm is 1×10 -7 cm 2 / Vs or later top 1×10 -5 cm 2 / Vs or less is preferable, but 1×10 -7 cm 2 / Vs or more 5 ×10 -5 cm 2 It is more preferable that the HOMO level is -6.0 eV / Vs or less. The above electron transporting materials preferably have an anthracene skeleton. It is more preferable that the aryl group contains a cyclic skeleton and a heterocyclic skeleton.

[0120] The organic compound used in the electron transport layer 114 is a compound having an aromatic ring in a furan ring of a furodiazine skeleton. Organic compounds having a condensed structure, metal complexes having a quinoline skeleton, benzoquinoline skeletons Metal complexes having an oxazole skeleton, and metal complexes having a thiazole skeleton. In addition to the above, oxadiazole derivatives, triazole derivatives, imidazole derivatives, oxadiazole derivatives, azole derivatives, thiazole derivatives, phenanthroline derivatives, quinoline ligand-containing quinoline derivatives Quinoline derivatives, benzoquinoline derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives Compounds, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, and other nitrogen-containing heteroaromatic compounds Materials with high electron transport properties, such as π-electron deficient heteroaromatic compounds, including Specifically, the above-mentioned light-emitting layer 113 can be used as a host material. or a host material in combination with the above fluorescent material. The materials listed as materials that can be used in the present invention can be used. Other substances having a high transporting property can be used. (114, 114a, 114b) can function as a single layer, but can also be stacked with two or more layers as necessary. By adopting this structure, the device characteristics can be improved.

[0121] Examples of metals, metal salts, metal oxides, or metal complexes that can be used in the electron transport layer 114 include In addition, the following substances may be used as necessary.

[0122] Metals include alkali metals, alkaline earth metals, and rare earth metals. Examples of these include Li, Na, K, Rb, Cs, Mg, Ca, Sr, and Ba.

[0123] Examples of metal salts include halides of the above metals and carbonates of the above metals. Specifically, LiF, NaF, KF, RbF, CsF, MgF2, CaF2, SrF2 , BaF2, LiCl, NaCl, KCl, RbCl, CsCl, MgCl2, CaCl 2, SrCl2, BaCl2, Li2CO3, Cs2CO3, etc.

[0124] Examples of metal oxides include oxides of the above metals. Specifically, Li2O, Examples include Na2O, Cs2O, MgO, CaO, etc.

[0125] The metal complex includes a ligand containing an 8-quinolinolato structure, a monovalent metal ion, and The ligand containing the 8-quinolinolato structure is preferably a metal complex having the following structure: 8-quinolinolato and methyl-substituted 8-quinolinolato (e.g., 2-methyl-substituted, 5-methyl substituted compound). The 8-quinolinolato structure is a substituted or This refers to the structure in which the proton of the -OH group in unsubstituted 8-quinolinol has been removed.

[0126] Therefore, the metal complexes having the above-mentioned alkali metals or alkaline earth metals include 8- 8-(quinolinolato)lithium, a lithium complex containing a quinolinolato structure Liq (abbreviation: Liq) is a sodium complex containing a ligand containing an 8-quinolinolato structure. 8-(quinolinolato) sodium (abbreviation: Naq), a compound containing the 8-quinolinolato structure Potassium complexes with ligands, such as 8-(quinolinolato)potassium (Kq), 8- A magnesium complex having a ligand containing a quinolinolato structure, (8-quinolinolato) Magnesium (abbreviation: Mgq2) and other metal complexes have the 8-quinolinolato structure. Zinc complexes with ligands containing 8-quinolinolatozinc (abbreviation: Znq2), etc. Examples include:

[0127] <Electron injection layer> The electron injection layer 115 is a layer for increasing the efficiency of injection of electrons from the second electrode (cathode) 102. and the work function value of the material of the cathode 102 and the LUMO It is preferable to use a material with a small difference (0.5 eV or less) between the values ​​of the energy levels. Therefore, the electron injection layer 115 may contain lithium, cesium, lithium fluoride (LiF), Cesium fluoride (CsF), calcium fluoride (CaF2), 8-(hydroxyquinolinate) Lithium (abbreviation: Liq), 2-(2-pyridyl)phenolatolithium (abbreviation: Li PP), 2-(2-pyridyl)-3-pyridinolatrium (abbreviation: LiPPy), 4- Phenyl-2-(2-pyridyl)phenolatolithium (abbreviation: LiPPP), lithium oxide Chemical compound (LiO x ), alkali metals such as cesium carbonate, alkaline earth metals, or the like These compounds can be used. Also, rare earth elements such as erbium fluoride (ErF3) can be used. Metallo-metal compounds can be used.

[0128] In addition, as shown in FIG. 1B, the two EL layers (103a, 103b) By providing a charge generating layer 104 between the electrodes, a structure in which multiple EL layers are laminated between a pair of electrodes is obtained. In this embodiment, the structure shown in FIG. ) described above, a hole injection layer (111), a hole transport layer (112), a light emitting layer (113), an electron The transport layer (114) and the electron injection layer (115) each function as a hole injection layer, as described in FIG. 1(B). Entry layers (111a, 111b), hole transport layers (112a, 112b), light emitting layers (113a, 113b), electron transport layer (114a, 114b), electron injection layer (115a, 115b) The functions and materials used are the same for each.

[0129] <Charge generation layer> In addition, the charge generating layer 104 in the light emitting device of FIG. 1(B) is a first electrode (anode) 10 When a voltage is applied between the first electrode 1, which is an anode, and the second electrode (cathode) 102, Electrons are injected into the EL layer 103a on the 01 side, and the EL layer 103 on the second electrode 102 side, which is the cathode, is The charge generating layer 104 has a function of injecting holes into the hole transporting material b. Even in a structure where an acceptor is added (P-type layer), the electron transport material is not donated to the electron The layer may have a structure in which a donor is added (N-type layer). The P-type layer may be laminated with the electron relay layer and the electron injection buffer layer described later. The above-mentioned materials may be used in combination with one or both of the layers. By forming the charge generating layer 104 using The voltage rise can be suppressed.

[0130] In the charge generating layer 104, a structure in which an electron acceptor is added to a hole transporting material (P-type layer) In this case, the material shown in this embodiment mode can be used as the hole transporting material. In addition, 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroethylene is used as an electron acceptor. Examples of the fluoroquinodimethane (abbreviation: F4-TCNQ), chloranil, etc. Further examples include oxides of metals belonging to groups 4 to 8 of the periodic table. Specifically, vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, molybdenum oxide, Examples include tungsten oxide, manganese oxide, and rhenium oxide.

[0131] In addition, in the charge generating layer 104, a structure in which an electron donor is added to an electron transporting material (N-type In the case of forming a layer (electron transporting layer), the material shown in this embodiment mode can be used as the electron transporting material. The electron donor may be an alkali metal, an alkaline earth metal, or a rare earth metal. Metals belonging to the 2nd and 13th groups of the periodic table and their oxides and carbonates are used. Specifically, lithium (Li), cesium (Cs), magnesium ( Mg), calcium (Ca), ytterbium (Yb), indium (In), lithium oxide It is preferable to use cesium carbonate or cesium carbonate. An organic compound may be used as the electron donor.

[0132] The electron relay layer, which is preferably combined with the P-type layer, is an electron injection buffer. By providing it between the a-type layer and the P-type layer, the interaction between the electron injection buffer layer and the P-type layer is prevented. The electron relay layer has a function of smoothly transferring electrons. The LUMO level of the electron transport material in the electron relay layer is The LUMO level of the electron-accepting material and the LUMO level of the material contained in the electron-injecting buffer layer The LUMO of the electron transport material used in the electron relay layer is preferably between The specific energy level of the level is -5.0 eV or more, preferably -5.0 eV or more to -3. The electron-transporting material used in the electron-relay layer is preferably a lid It is possible to use cyanine-based materials or metal complexes with metal-oxygen bonds and aromatic ligands. preferable.

[0133] The electron injection buffer layer may include alkali metals, alkaline earth metals, rare earth metals, and their corresponding Compounds of alkali metal compounds (oxides such as lithium oxide, halides, lithium carbonate, etc.) and carbonates such as cesium carbonate), alkaline earth metal compounds (oxides, halides, carbonates), or compounds of rare earth metals (including oxides, halides, and carbonates) It is possible to use a substance having a high electron injection property such as the above.

[0134] In addition, when the electron injection buffer layer is formed containing an electron transport material and an electron donor material, The electron donating substances include alkali metals, alkaline earth metals, rare earth metals, and These compounds (alkali metal compounds (oxides such as lithium oxide, halides, lithium carbonate, etc.) Alkaline earth metal compounds (including oxides, halides, etc.) compounds of rare earth metals (including oxides, halides, carbonates) )), tetrathianaphthacene (abbreviation: TTN), nickelocene, decamethylnickelocene, As the electron transporting material, an organic compound such as benzene can be used. The second insulating layer 11 can be formed using the same material as that for forming the electron transport layer.

[0135] In FIG. 1B, the EL layer 103 is configured to have two layers stacked. A stacked structure of three or more EL layers may be formed by providing a charge generating layer between the layers.

[0136] The charge generating layer may be used in place of the electron injection layer. In this case, the electron injection buffer layer, the electron relay layer, and the P-type layer are stacked in this order from the anode side. It is preferable.

[0137] <Substrate> The light-emitting device shown in this embodiment mode can be formed over various substrates. The type of the substrate is not limited to a specific one. An example of the substrate is a semiconductor substrate (e.g. For example, single crystal substrate or silicon substrate), SOI substrate, glass substrate, quartz substrate, plastic Substrate, metal substrate, stainless steel substrate, substrate with stainless steel foil, Tungsten substrate, substrate with tungsten foil, flexible substrate, lamination film Examples of the material include paper containing fibrous materials, and base films.

[0138] Examples of the glass substrate include barium borosilicate glass and aluminoborosilicate glass. Glass or soda lime glass. Flexible substrates, lamination films, etc. Examples of base films include polyethylene terephthalate (PET), polyethylene Plastics such as polyolefin naphthalate (PEN) and polyethersulfone (PES) Synthetic resins such as acrylic resin, polypropylene, polyester, polyvinyl fluoride, Or polyvinyl chloride, polyamide, polyimide, aramid resin, epoxy resin, inorganic vapor deposition Examples of the material include films and papers.

[0139] Note that the light-emitting device shown in this embodiment mode can be manufactured by a vacuum process such as an evaporation method or a spin Solution processes such as the ink-jet method and the deposition method can be used. In this case, sputtering, ion plating, ion beam deposition, and molecular beam deposition are used. , physical vapor deposition (PVD) method such as vacuum deposition method, chemical vapor deposition (CVD) method, etc. In particular, the functional layer (hole injection layer (111, 111a)) included in the EL layer of the light-emitting device can be formed. , 111b), hole transport layer (112, 112a, 112b), light emitting layer (113, 113a) , 113b), electron transport layer (114, 114a, 114b), electron injection layer (115, 11 5a, 115b) and the charge generating layer (104) are formed by deposition (vacuum deposition, etc.); Coating method (dip coating, die coating, bar coating, spin coating, spray coating) printing method (inkjet method, screen (stencil printing) method, offset (lithographic printing method, etc.) printing method, flexography (letterpress printing) method, gravure method, microcontact method, nanoimprinting method The film can be formed by a method such as a coating method.

[0140] The EL layers (103, 103a, 103b) of the light-emitting device shown in this embodiment are Each functional layer (hole injection layer (111, 111a, 111b), hole transport layer (112, 11 2a, 112b), light emitting layer (113, 113a, 113b), electron transport layer (114, 11 4a, 114b), electron injection layer (115, 115a, 115b) and charge generation layer (104) The materials are not limited to those mentioned above, and other materials may be used as long as they fulfill the functions of each layer. As an example, a polymer compound (oligomer) can be used in combination. mers, dendrimers, polymers, etc.), medium molecular weight compounds (compounds in the intermediate range between low molecular weight and high molecular weight compounds) (molecular weight: 400 to 4000), inorganic compounds (quantum dot materials, etc.), etc. can be used. The quantum dot materials include colloidal quantum dot materials and alloy quantum dot materials. , core-shell type quantum dot materials, core type quantum dot materials, etc. can be used.

[0141] The structure described in this embodiment mode can be used in appropriate combination with structures described in other embodiments. It is possible.

[0142] (Embodiment 2) In this embodiment, a light-emitting device according to one embodiment of the present invention will be described. The light emitting device shown in FIG. 2 comprises a transistor (FET) 202 and a light emitting device on a first substrate 201. (203R, 203G, 203B, 203W) are electrically connected to each other. A light emitting device of a light emitting type, which has a plurality of light emitting devices (203R, 203G, 203B, 20 3W) has a common EL layer 204, and each light-emitting device is divided into two layers according to the color of the light emitted by each light-emitting device. The device has a microcavity structure with tuned optical distance between electrodes. The light emitted from the layer 204 is reflected by a color filter (206R, The light emitting device is a top emission type in which light is emitted through the respective light sources 206G and 206B.

[0143] In the light-emitting device shown in FIG. 2A, the first electrode 207 is formed so as to function as a reflective electrode. The second electrode 208 is formed to have a light (visible light or near infrared light) transparency and The electrode is formed so as to function as a semi-transmissive and semi-reflective electrode having both a transmissive and reflective function. In other embodiments, the electrode material for forming the first electrode 207 and the second electrode 208 may be The above description can be referred to and used appropriately.

[0144] In FIG. 2A, for example, the light-emitting device 203R is a red light-emitting device, The light emitting device 203G is a green light emitting device, the light emitting device 203B is a blue light emitting device, When the light emitting device 203W is a white light emitting device, as shown in FIG. 03R is such that the optical distance between the first electrode 207 and the second electrode 208 is 200R. The light emitting device 203G is adjusted so that the optical distance between the first electrode 207 and the second electrode 208 is The distance between the first electrode 207 and the second electrode 208 is adjusted to 200G. The optical distance between the pole 208 and the optical axis 200B is adjusted. Then, in the light-emitting device 203R, a conductive layer 210R is laminated on the first electrode 207, and the light-emitting device By laminating a conductive layer 210G in the device 203G, optical adjustment can be performed. Cut.

[0145] Color filters (206R, 206G, 206B) are formed on the second substrate 205. Color filters allow certain wavelengths of visible light to pass through and block certain wavelengths. Therefore, as shown in FIG. 2A, the filter overlaps with the light-emitting device 203R. A color filter 206R that transmits only the red wavelength region is provided at a position corresponding to the Red light can be obtained from the optical device 203R. A color filter 206G that transmits only the green wavelength region is provided at a position corresponding to the Green light can be obtained from the optical device 203G. By providing a color filter 206B that transmits only the blue wavelength range at a position corresponding to the Blue light can be obtained from the optical device 203B. However, the light-emitting device 203W is White light can be obtained without the use of a color filter. A black layer (black matrix) 209 may be provided on the end of the filter. The color filters (206R, 206G, 206B) and the black layer 209 are made of transparent materials. It may be covered with an overcoat layer used.

[0146] In FIG. 2A, a structure (top emission type) in which light is extracted on the second substrate 205 side is used. A light emitting device is shown, but as shown in FIG. 2(C), a first substrate on which a FET 202 is formed The light emitting device may have a structure in which light is extracted from the 201 side (bottom emission type). In the case of a bottom emission type light emitting device, the first electrode 207 is a semi-transmissive and semi-reflective electrode. The first electrode 206 is formed to function as a reflecting electrode, and the second electrode 208 is formed to function as a reflecting electrode. The first substrate 201 is at least a light-transmitting substrate. (206R', 206G', 206B') are light-emitting devices (2 It is sufficient to provide them on the first substrate 201 side relative to the first and second electrodes 203R, 203G, and 203B.

[0147] In addition, in FIG. 2(A), the light emitting devices are a red light emitting device, a green light emitting device, and a blue light emitting device. Although the cases of a color light-emitting device and a white light-emitting device have been described, The device is not limited to this configuration, and may be a yellow light-emitting device or an orange light-emitting device. In order to manufacture these light-emitting devices, an EL layer (light-emitting layer) may be used. layer, hole injection layer, hole transport layer, electron transport layer, electron injection layer, charge generation layer, etc.) For details, refer to the descriptions of other embodiments and use them as appropriate. It is necessary to select a color filter appropriately according to the emission color of the light emitting device.

[0148] By adopting the above-mentioned configuration, a light emitting device having light emitting devices that emit light of a plurality of colors can be obtained. You can get a position.

[0149] Note that the structure described in this embodiment mode may be used in appropriate combination with structures described in other embodiments. It is possible to do so.

[0150] (Embodiment 3) In this embodiment, a light-emitting device which is one embodiment of the present invention will be described.

[0151] By applying the device configuration of the light-emitting device according to one embodiment of the present invention, A light-emitting device of an anode type or a cathode type can be manufactured. An active matrix type light emitting device combines a light emitting device and a transistor (FET). Therefore, the passive matrix type light emitting device and the active matrix type light emitting device are Any of the above-mentioned light-emitting devices is included in one embodiment of the present invention. The light emitting device described in the other embodiments can be applied to the device.

[0152] In this embodiment mode, an active matrix light emitting device will be described with reference to FIG.

[0153] 3A is a top view showing the light emitting device, and FIG. 3B is a top view showing the light emitting device along the dashed line AA in FIG. The active matrix type light emitting device has a first substrate 301 and a second substrate 302. A pixel portion 302, a driver circuit portion (source line driver circuit) 303, and a driver circuit portion (gate The pixel section 302 and the driver circuit section (304a, 304b) are connected to the pixel section 302. The first substrate 301 and the second substrate 302 are connected by a seal material 305. It is sealed between the plate 306 .

[0154] Moreover, on the first substrate 301, a lead wiring 307 is provided. The driver is electrically connected to the FPC 308, which is an external input terminal. An external signal (e.g., a video signal, a clock signal, etc.) is input to the driving circuit unit (303, 304a, 304b). The FPC308 also transmits signals such as the lock signal, start signal, and reset signal, as well as electrical potential. A printed wiring board (PWB) may be attached. Note that these FPCs and PWBs The state in which the light emitting device is attached is included in the light emitting device.

[0155] Next, a cross-sectional structure is shown in FIG.

[0156] The pixel section 302 includes a FET (switching FET) 311 and a FET (current control FET). 312, and a plurality of pixels having a first electrode 313 electrically connected to the FET 312. The number of FETs in each pixel is not particularly limited, and may be any number. It can be provided appropriately as needed.

[0157] The FETs 309, 310, 311, and 312 are not particularly limited, and may be, for example, staggered. In addition, top-gate and bottom-gate transistors can be used. The transistor may have a structure such as a Tom-gate type.

[0158] The semiconductors that can be used for these FETs 309, 310, 311, and 312 are The crystallinity is not particularly limited, and may be an amorphous semiconductor, a semiconductor having crystallinity (a microcrystalline semiconductor, Any of polycrystalline semiconductors, single crystal semiconductors, and semiconductors having crystalline regions in some parts may be used. By using a crystalline semiconductor, deterioration of transistor characteristics can be suppressed. This is preferable because it is possible to

[0159] In addition, these semiconductors include, for example, Group 14 elements, compound semiconductors, and oxide semiconductors. , organic semiconductors, etc. can be used. Representative examples include semiconductors containing silicon, gallium, etc. A semiconductor containing arsenic, an oxide semiconductor containing indium, or the like can be used.

[0160] The driving circuit section 303 includes an FET 309 and an FET 310. is formed by a circuit containing transistors of one polarity (either N-type or P-type only). Alternatively, the transistor may be formed of a CMOS circuit including an N-type transistor and a P-type transistor. Also, a configuration having an external driving circuit may be used.

[0161] The end of the first electrode 313 is covered with an insulator 314. , negative photosensitive resin, positive photosensitive resin (acrylic resin), and other organic compounds, Inorganic compounds such as silicon, silicon oxynitride, and silicon nitride can be used. It is preferable that the upper or lower end of the object 314 has a suitable curvature. This allows the coating properties of the film formed on the upper layer of the border 314 to be good.

[0162] An EL layer 315 and a second electrode 316 are stacked on the first electrode 313. 315 is a light-emitting layer, a hole injection layer, a hole transport layer, an electron transport layer, an electron injection layer, a charge generation layer, etc. Yes.

[0163] The configuration of the light-emitting device 317 shown in this embodiment is the same as that described in the other embodiments. Although not shown here, the second electrode 316 is an external It is electrically connected to the FPC 308 which is the input terminal.

[0164] In addition, although only one light-emitting device 317 is shown in the cross-sectional view shown in FIG. In the display unit 302, a plurality of light emitting devices are arranged in a matrix. The element 302 is provided with three light emitting devices capable of selectively emitting light of three colors (R, G, B). In addition, it is possible to form a light-emitting device capable of full color display. In addition to light-emitting devices that can emit white (W), yellow (Y), It is also possible to form a light emitting device that emits light of blue, magenta (M), cyan (C), etc. For example, a light-emitting device that emits three types of light (R, G, B) can emit several of the above-mentioned types of light. By adding a light-emitting device that can be used in a wide range of applications, the color purity can be improved and power consumption can be reduced. In addition, full color display is possible by combining with a color filter. The light emitting device may be a light emitting device having a color filter of red (R), green (G), Blue (B), cyan (C), magenta (M), yellow (Y), etc. can be used.

[0165] The FETs (309, 310, 311, 312) on the first substrate 301 and the light emitting device 31 7 is a process for bonding the second substrate 306 and the first substrate 301 with a seal material 305. As a result, a space 3 surrounded by the first substrate 301, the second substrate 306, and the sealant 305 is formed. The space 318 is filled with an inert gas (such as nitrogen or argon). ) or an organic material (including a sealant 305).

[0166] The sealing material 305 can be made of epoxy resin or glass frit. It is preferable to use a material that is as impermeable to moisture and oxygen as possible for the insulating material 305. The second substrate 306 may be made of the same material as the first substrate 301. Therefore, it is possible to use various substrates described in other embodiments as appropriate. The substrates used are glass and quartz, as well as FRP (Fiber-Reinforced Plastics). d Plastics), PVF (Polyvinyl fluoride), polyester or acrylic A plastic substrate made of a plastic resin or the like can be used. When using a glass substrate, the first substrate 301 and the second substrate 306 are preferably made of glass from the viewpoint of adhesiveness. It is preferably a substrate.

[0167] In this manner, an active matrix light emitting device can be obtained.

[0168] In addition, when an active matrix type light emitting device is formed on a flexible substrate, The FET and the light emitting device may be directly formed, or the FET and the light emitting device may be formed on a separate substrate having a release layer. After forming the optical device, the FET and the light-emitting device are separated by applying heat, force, laser irradiation, etc. The substrate may be peeled off at a peeling layer and then transferred onto a flexible substrate. Examples of the insulating layer include a laminate of inorganic films such as a tungsten film and a silicon oxide film, and a laminate of a functional film such as polyimide. A flexible substrate may be used for forming a transistor. In addition to the substrates that can be used, paper substrates, cellophane substrates, aramid film substrates, polyimide substrates, Film substrate, cloth substrate (natural fibers (silk, cotton, linen), synthetic fibers (nylon, polyurethane, polyester) polyester) or regenerated fibers (acetate, cupra, rayon, regenerated polyester) The substrates include a leather substrate, a rubber substrate, etc. This allows for excellent durability and heat resistance, as well as lighter weight and thinner construction.

[0169] In addition, the driving of the light emitting device included in the active matrix type light emitting device is performed by the light emitting device A structure that emits light in a pulsed form (for example, using a frequency of kHz or MHz) and is used for display. The light-emitting device formed using the organic compound has excellent frequency characteristics. Therefore, the time for driving the light-emitting device can be shortened, and power consumption can be reduced. In addition, the reduction in operating time reduces heat generation, which reduces the deterioration of the light-emitting device. It is also possible.

[0170] Note that the structure shown in this embodiment mode may be used in appropriate combination with structures shown in other embodiment modes. It is possible.

[0171] (Embodiment 4) In this embodiment, a light-emitting device according to one embodiment of the present invention We will explain examples of various electronic devices and automobiles that have been completed using a light-emitting device with a seat. The light-emitting device is mainly applied to a display portion in the electronic device described in this embodiment mode. It can be used.

[0172] The electronic device shown in FIG. 4A to FIG. 4E includes a housing 7000, a display portion 7001, a speaker 7003, LED lamp 7004, operation key 7005 (power switch or operation switch ), a connection terminal 7006, a sensor 7007 (force, displacement, position, velocity, acceleration, angular velocity , rotation speed, distance, light, liquid, magnetism, temperature, chemicals, sound, time, hardness, electric field, current, voltage , power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared measurement functions. ), a microphone 7008, etc.

[0173] FIG. 4A shows a mobile computer, which includes, in addition to the above, a switch 7009, a red It may have an outside line port 7010, etc.

[0174] FIG. 4B shows a portable image reproducing device (for example, a DVD reproducing device) equipped with a recording medium. In addition to the above, it has a second display unit 7002, a recording medium reading unit 7011, etc. This can be done.

[0175] Figure 4(C) shows a digital camera with a television receiving function, which, in addition to the above, has an antenna 7014, a shutter button 7015, an image receiving unit 7016, etc.

[0176] FIG. 4D shows a portable information terminal. The portable information terminal displays information on three or more screens of a display unit 7001. In this example, information 7052, information 7053, and information 7054 are For example, the user may carry a mobile information terminal in his / her breast pocket. Information displayed in a position that can be observed from above the mobile information terminal when the terminal is stored. The user can check the display without taking the mobile information terminal out of his pocket. and can decide, for example, whether to answer the phone or not.

[0177] FIG. 4E shows a portable information terminal (including a smartphone), in which a display unit 7000 is mounted on a housing 7000. 001, operation keys 7005, etc. The portable information terminal may have a speaker, 9003, a connection terminal 7006, a sensor 9007, etc. may be provided. It can display text and image information on its multiple sides. Here, three icons are shown. 50 is displayed on the display unit 7001. It can also be displayed on other surfaces. Examples of information 7051 include email, SNS, Notifications of incoming calls, emails, SNS messages, sender name, date, time, battery The remaining battery power, antenna reception strength, etc. Or, the information 7051 is displayed. An icon 7050 or the like may be displayed at the location.

[0178] Figure 4(F) shows a large television set (also called a television or television receiver). The electronic device may have a housing 7000, a display unit 7001, and the like. The housing 7000 is supported by a support 7018. The operation of the display unit 7111 can be performed by a separate remote control unit 7111. The display unit 7001 may be provided with a touch sensor, and the operation can be performed by touching the display unit 7001 with a finger or the like. The remote control unit 7111 may output information The remote control 7111 may have a display unit that displays the operation keys or buttons. The channel and volume can be controlled by the touch panel, and the display unit 7001 displays The image displayed can be manipulated.

[0179] The electronic devices shown in FIGS. 4A to 4F can have various functions. For example, , the function to display various information (still images, videos, text images, etc.) on the display unit, Functions such as displaying calendars, dates, or times, and various software (programs) The function of controlling processing by the wireless communication function, It has a function to connect to a data network, and a wireless communication function to transmit or receive various data. The function of reading out the program or data recorded on the recording medium and displaying it on the display unit. Furthermore, in an electronic device having a plurality of display units, One display section is used primarily to display image information, and the other display section is used primarily to display text information. Or, a function to display images that take parallax into account on multiple displays to create a stereoscopic image. Furthermore, in electronic devices having an image receiving unit, Functions for taking still images, shooting videos, and automatically or manually correcting captured images Function, function to save the captured image to a recording medium (external or built-in to the camera), function to save the captured image The display unit can have a function of displaying the above-mentioned information on the display unit. The functions that the electronic device shown in the figure can have are not limited to these, and the electronic device may have a variety of functions. can be done.

[0180] FIG. 4(G) shows a wristwatch-type mobile information terminal that can be used, for example, as a smart watch. This wristwatch-type mobile information terminal is made up of a housing 7000, a display unit 7001, and operation buttons. Tan 7022, 7023, Connection terminal 7024, Band 7025, Microphone 7026 The display unit 7001 has a curved display surface. This allows the display to be displayed along the curved display surface. For example, hands-free conversation is possible by communicating with a wireless headset. In addition, the connection terminal 7024 can be used to transmit data to and from other information terminals. Charging can also be performed by wireless power supply.

[0181] A display unit 7001 mounted on a housing 7000 that also serves as a bezel has a non-rectangular display area. The display unit 7001 has an icon 7027 representing the time, other icons 702 8, etc. The display unit 7001 is equipped with a touch sensor (input device). The display may be a touch panel (input / output device) mounted thereon.

[0182] The smart watch shown in FIG. 4G can have various functions. For example, , the function to display various information (still images, videos, text images, etc.) on the display unit, Functions such as displaying calendars, dates, or times, and various software (programs) The function of controlling processing by the wireless communication function, It has a function to connect to a data network, and a wireless communication function to transmit or receive various data. The function of reading out the program or data recorded on the recording medium and displaying it on the display unit. It may have the function of

[0183] In addition, a speaker, a sensor (force, displacement, position, velocity, acceleration, angular velocity, degree, rotation speed, distance, light, liquid, magnetism, temperature, chemicals, sound, time, hardness, electric field, current, Includes functions to measure pressure, power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared rays. ), a microphone, etc.

[0184] Note that the light-emitting device which is one embodiment of the present invention can be used for each display portion of the electronic devices described in this embodiment. This makes it possible to realize electronic devices with long life.

[0185] As an electronic device to which the light-emitting device is applied, a folding type as shown in FIG. A foldable mobile information terminal is an example. Figure 5(A) shows a mobile information terminal in an unfolded state. 9310. Also, FIG. 5(B) shows the state of the device from either the unfolded or folded state. FIG. 5C shows a portable information terminal 9310 in the process of changing to the other state. The portable information terminal 9310 is in a folded state. When folded, it is highly portable, and when unfolded, it has a seamless, large display area for easy viewing of all the information. Excellent performance.

[0186] The display unit 9311 is supported by three housings 9315 connected by hinges 9313. The display unit 9311 is a touch panel (input / output) equipped with a touch sensor (input device). The display unit 9311 may be connected to two housings via a hinge 9313. By bending the gap between the terminals 9315, the portable information terminal 9310 can be folded from the unfolded state. The light-emitting device of one embodiment of the present invention can be reversibly transformed into a display state. The display portion 9311 can be used as a display unit. In addition, a long-life electronic device can be realized. The display area 9312 in FIG. 1 is located on the side of the portable information terminal 9310 in the folded state. The display area 9312 displays information icons and frequently used apps and programs. You can display shortcuts to programs, check information, and launch apps. It can be done smoothly.

[0187] In addition, an automobile to which the light emitting device is applied is shown in FIG. 6(A) and FIG. 6(B). That is, the light emitting device can be integrated with the automobile. The exterior lights 5101 (including the rear of the car), the wheels 5102, and the doors 5103, or the whole of the vehicle shown in FIG. A display unit 5104 on the inside, a steering wheel 5105, a shift lever 5106, and a seat 510 7. It can be applied to inner rear view mirror 5108, windshield 5109, etc. It may also be applied to other parts of glass windows.

[0188] In this manner, an electronic device or an automobile to which the light-emitting device according to one embodiment of the present invention is applied can be obtained. In this case, it is possible to realize an electronic device with a long life. The sub-devices and automobiles are not limited to those shown in this embodiment, but can be applied in various fields. It is possible.

[0189] Note that the structure described in this embodiment mode may be used in appropriate combination with structures described in other embodiment modes. It is possible.

[0190] (Embodiment 5) In this embodiment, a light-emitting device which is one embodiment of the present invention or a light-emitting device which is a part thereof will be described. The structure of a lighting device manufactured by applying the above will be described with reference to FIG.

[0191] 7(A) and 7(B) are cross-sectional views of an example of a lighting device. This is a bottom emission type lighting device that extracts light from the plate side. It is a top-emission lighting device that extracts light from the inside.

[0192] The lighting device 4000 shown in FIG. 7A has a light-emitting device 4002 on a substrate 4001. The light-emitting device 400 further includes a substrate 4003 having projections and recesses on the outer side of the substrate 4001. 2 has a first electrode 4004 , an EL layer 4005 , and a second electrode 4006 .

[0193] The first electrode 4004 is electrically connected to the electrode 4007, and the second electrode 4006 is electrically connected to the electrode 4008. 008. An auxiliary wiring electrically connected to the first electrode 4004. An insulating layer 4010 may be formed on the auxiliary wiring 4009. There are.

[0194] The substrate 4001 and the sealing substrate 4011 are bonded together with a sealant 4012. A desiccant 4013 is provided between the sealing substrate 4011 and the light emitting device 4002. It is preferable that the substrate 4003 has a concave and convex shape as shown in FIG. This can improve the efficiency of extracting light generated in the chair 4002.

[0195] A lighting device 4200 in FIG. 7B includes a light-emitting device 4202 on a substrate 4201. The optical device 4202 includes a first electrode 4204, an EL layer 4205, and a second electrode 4206. has.

[0196] The first electrode 4204 is electrically connected to the electrode 4207, and the second electrode 4206 is electrically connected to the electrode 4208. 208. The auxiliary wiring 4 is electrically connected to the second electrode 4206. An insulating layer 4210 may be provided under the auxiliary wiring 4209. stomach.

[0197] The substrate 4201 and the sealing substrate 4211 having projections and recesses are bonded with a sealant 4212. In addition, a barrier film 4213 and a planarization film 4214 are provided between the sealing substrate 4211 and the light emitting device 4202. Note that the sealing substrate 4211 has projections and recesses as shown in FIG. Therefore, the extraction efficiency of the light generated in the light emitting device 4202 can be improved.

[0198] An example of the application of these lighting devices is a ceiling light for indoor lighting. There are two types of ceiling lights: ceiling-mounted and ceiling-embedded. Such an illumination device is constructed by combining a light-emitting device with a housing or a cover.

[0199] Other applications include footlights that can illuminate the floor and increase safety at your feet. It is also possible to use a footlight in a bedroom, on stairs, or in a hallway. In the case of , the size and shape can be changed appropriately according to the size and structure of the room. It is also possible to combine the device with a support stand to create a stationary lighting device. .

[0200] It can also be used as a sheet-shaped lighting device (sheet-shaped lighting). The lighting is attached to the wall, so it doesn't take up much space and can be used for a wide range of purposes. It is also easy to make it larger. It can also be used on curved walls and housings.

[0201] In addition to the above, a light-emitting device according to one embodiment of the present invention may be attached to a part of furniture in a room. The light-emitting device is a part of this, and it is used to create a lighting device that also functions as furniture. can be done.

[0202] As described above, various lighting devices using the light-emitting device can be obtained. is included in one aspect of the present invention.

[0203] The structure shown in this embodiment mode may be used in appropriate combination with structures shown in other embodiment modes. It is possible. EXAMPLES

[0204] In this example, a light-emitting device 1 was fabricated as a light-emitting device according to one embodiment of the present invention. The device structure, fabrication method, and characteristics of the device are described. A comparative light-emitting device 2 was fabricated and the two were compared. The chair structure is shown in FIG. 8, and the specific configuration is shown in Table 1. The chemical formula is shown below.

[0205] [Table 1]

[0206] [ka]

[0207] <Creating light-emitting devices> The light emitting device shown in this embodiment has a first electrode formed on a substrate 900 as shown in FIG. On the substrate 901, a hole injection layer 911, a hole transport layer 912, a light emitting layer 913, an electron transport layer 914, and an electrode A second electrode 903 is laminated on the electron injection layer 915. It has a structure.

[0208] First, a first electrode 901 was formed on a substrate 900. The electrode area was 4 mm 2 (2mm x 2 The thickness of the first electrode 901 was 1 mm. The substrate 900 was a glass substrate. , Indium tin oxide containing silicon oxide (ITSO) was sputtered to a thickness of 70 nm. The film was formed to a thickness of .

[0209] As a pretreatment, the surface of the substrate is washed with water, baked at 200°C for 1 hour, and then UV-treated. The treatment was carried out for 370 seconds. Then, 1 × 10 -4 Vacuum steaming with the inside pressure reduced to about Pa The substrate was introduced into the vacuum deposition apparatus, and the substrate was vacuum baked at 170°C for 30 minutes in the heating chamber of the vacuum deposition apparatus. After the formation, the substrate was allowed to cool for about 30 minutes.

[0210] Next, a hole injection layer 911 was formed on the first electrode 901. The hole injection layer 911 was formed by vacuum evaporation. 1×10 -4 After depressurizing to 100 Pa, 1,3,5-tri(dibenzothiophene-4 -yl)benzene (abbreviation: DBT3P-II) and molybdenum oxide, : Molybdenum oxide = 2:1 (mass ratio) and formed by co-evaporation to a film thickness of 60 nm did.

[0211] Next, a hole transport layer 912 was formed on the hole injection layer 911. The hole transport layer 912 was made of N-( 1,1'-biphenyl-4-yl)-N-[4-(9-phenyl-9H-carbazole- 3-yl)phenyl]-9,9-dimethyl-9H-fluoren-2-amine (abbreviation: PC The film was formed by vapor deposition using BBiF to a thickness of 20 nm.

[0212] Next, a light-emitting layer 913 was formed on the hole-transporting layer 912 .

[0213] In the case of the light-emitting device 1, the light-emitting layer 913 is 8-[(3′-dibenzothiophene-4-yl)phenyl] (2,3-b)biphenyl-3-yl]naphtho[2',1':4,5]furo[2,3-b]pyrazine In addition to (abbreviation: 8mDBtBPNfpr(II)) and PCBBiF, guest materials ( Phosphorescent material: Bis(4,6-diphenylpyrimidinato)iridium(III) (abbreviation: [Ir(dppm)2(acac)]), with a weight ratio of 8mDBtBPNf pr(II):PCBBiF:[Ir(dppm)2(acac)]=0.75:0.2 The thickness of the film was 40 nm. In the case of optical device 2, 12-[(3'-dibenzothiophen-4-yl)biphenyl- 3-yl]phenanthro[9',10':4,5]furo[2,3-b]pyrazine (abbreviation: In addition to 12mDBtBPPnfpr) and PCBBiF, guest materials (phosphorescent materials ) is [Ir(dppm)2(acac)], and the weight ratio is 12mDBtBPPn fpr:PCBBiF:[Ir(dppm)2(acac)]=0.75:0.25:0 The film thickness was 40 nm.

[0214] Next, an electron transport layer 914 was formed on the light emitting layer 913 .

[0215] In the case of the light-emitting device 1, the electron transport layer 914 is made of 8mDBtBPNfpr(II) having a thickness of 25 nm, 2,9-bis(naphthalene-2-yl)-4,7-diphenyl-1,10- Phenanthroline (NBphen) was evaporated in order to form a film with a thickness of 15 nm. In the case of the comparative light-emitting device 2, the thickness of the 12mDBtBPPnfpr film was 25 The film was formed by sequential deposition so that the thickness of the thin film was 15 nm and that of NBphen was 15 nm.

[0216] Next, the electron injection layer 915 was formed on the electron transport layer 914. The electron injection layer 915 was made of fluoride. Lithium (LiF) was used and the film was formed by vapor deposition to a thickness of 1 nm.

[0217] Next, a second electrode 903 was formed on the electron injection layer 915. The second electrode 903 was made of aluminum. The aluminum was deposited by vapor deposition to a thickness of 200 nm. Thus, the second electrode 903 functions as a cathode.

[0218] Through the above steps, a light-emitting device having an EL layer 902 sandwiched between a pair of electrodes is formed on the substrate 900. The hole injection layer 911, the hole transport layer 912, and the light emitting layer 913 were formed. The organic electroluminescent layer 913, the electron transport layer 914, and the electron injection layer 915 constitute an EL layer in one embodiment of the present invention. In addition, the deposition process in the above-mentioned manufacturing method is all performed by resistance heating. The deposition method was used.

[0219] The light-emitting device fabricated as described above is sealed with another substrate (not shown). When sealing using another substrate (not shown), the device is sealed in a glove box with a nitrogen atmosphere. In the above, another substrate (not shown) coated with a sealant that is hardened by ultraviolet light is placed on the substrate 900. The substrate 900 is fixed on the substrate 900 so that the sealant adheres to the periphery of the light emitting device formed on the substrate 900. The plates were bonded together. During sealing, 365 nm ultraviolet light was applied at 6 J / cm. 2 Irradiate the sealant to harden it. The sealant was stabilized by heating at 80° C. for 1 hour.

[0220] <Operation characteristics of light-emitting devices> The operating characteristics of each light-emitting device were measured. The current density-luminance characteristics were also measured as a result of the operating characteristics of each light-emitting device. Fig. 9 shows the voltage-luminance characteristics, Fig. 10 shows the luminance-current efficiency characteristics, and Fig. 11 shows the voltage-current characteristics. 12 respectively.

[0221] Also, 1000cd / m 2 The main initial characteristics of each light-emitting device in the vicinity are shown in Table 2 below. show.

[0222] [Table 2]

[0223] From the above results, the light emitting device 1 shown in this example has the initial In terms of characteristics, it was found that the device exhibited better luminous efficiency than the comparative light-emitting device 2.

[0224] In addition, the light-emitting device 1 and the comparative light-emitting device 2 were 2 Current at current density of The emission spectrum when the light emitting device 1 and the light emitting device 2 were passed through the light emitting device 1 is shown in FIG. The emission spectra of the comparative light-emitting device 1 and the comparative light-emitting device 2 have a peak at about 589 nm. This is due to the emission of [Ir(dppm)2(acac)] contained in the light-emitting layer 913. This suggests that

[0225] Next, a reliability test was carried out on the light-emitting device 1 and the comparative light-emitting device 2. The results of the experiment are shown in Fig. 14. In Fig. 14, the vertical axis shows the normalized value when the initial luminance is set to 100%. The horizontal axis indicates the brightness (%), and the horizontal axis indicates the device operating time (h). 1000cd / cm 2 The results shown in Figure 14 show that the It was found that the optical device 1 exhibited higher reliability than the comparative light-emitting device 2.

[0226] Here, the guest material (phosphorescent material) used is [Ir(dppm)2(acac The absorption spectrum of )] in dichloromethane solution is shown in Figure 21(A). An enlarged view of the absorption edge of each of the fluorescein fluorine-containing ... The T1 level (T G : Absorption of phosphorescent materials The T1 level derived from the absorption edge of the spectrum is 2.22 eV (= 559 nm). Therefore, in the light-emitting layer 913 of the light-emitting device 1 shown in this example, As an organic compound having a naphtho[2',1':4,5]furo[2,3-b]pyrazine skeleton, Using 8mDBtBPNfpr(II), we obtained phosphorescence with a T1 level of 2.5 eV or less. As a substance, the T1 level is 2.22 eV (based on the absorption spectrum measured in dichloromethane solution). The calculation is based on [Ir(dppm)2(acac)]. The light-emitting layer 913 of the light-emitting device 2 contains naphtho[2',1':4,5]furo[2,3-b] As an organic compound that does not have a pyrazine skeleton, 12mDBtBPPnfp The luminescent material used was the same as that used for the luminescent device 1, [Ir(dppm)2(acac)]. It is.

[0227] Therefore, the light emitting device 1 of this example has a better initial characteristic than the comparative light emitting device 2. Not only did the device show good luminous efficiency, but it also showed improved reliability, which is one aspect of the present invention. In the light-emitting layer 913 of the light-emitting device 1 having a certain configuration, 8mDBtBPN in an excited state The efficiency of energy transfer from fpr(II) to [Ir(dppm)2(acac)] is increased. This result can be said to be due to the fact that

[0228] In addition, in FIG. 22(A), a naphtho[2',1':4,5]furo[2,3-b]pyrazine skeleton is shown. The phosphorescence spectrum of 8mDBtBPNfpr(II), an organic compound having the formula 22(B) is an enlarged view of the vicinity of the emission edge. The phosphorescence spectrum was measured using a micro PL microscope (Lab The measurement temperature was 10K. The measurement was performed by time-resolved measurement using a laser shutter. The T1 level (T H :Organic host material The T1 level derived from the emission edge on the short wavelength side of the phosphorescence spectrum of the compound is 2. 52 eV (= 492 nm). Therefore, T H -T G is 0.30 eV, and 0.1 eV≦ T H -T G The condition of ≦0.4 eV is met. EXAMPLES

[0229] In this example, a light-emitting device 3 was fabricated as a light-emitting device according to one embodiment of the present invention. The results of measuring the characteristics are shown below.

[0230] The element structure of the light-emitting device 3 produced in this example is the same as that shown in FIG. 8 in Example 1. The specific configuration of each layer that constitutes the element structure is as shown in Table 3. The chemical formulas of the materials used in this example are shown below.

[0231] [Table 3]

[0232] [ka]

[0233] The hole transport layer 912 is formed of 4,4'-diphenyl-4''-(9-phenyl-9H- Carbazol-3-yl)triphenylamine (abbreviation: PCBBi1BP) was used. In addition, the light-emitting layer 913 contains 8-[(3′-dibenzothiophen-4-yl)biphenyl-3 -yl]naphtho[2',1':4,5]furo[2,3-b]pyrazine (abbreviation: 8mDBt BPNfpr(II)), and 3,3'-bis(9-phenyl-9H-carbazole) In addition to PCCP, we also use [2-(4-methylphenyl)-2-phenylpropene (PCCP)] as a guest material (phosphorescent material). -5-phenyl-2-pyridinyl-κN)phenyl-κC]bis[2-(2-pyridinyl [Ir(ppy)2(mdppy)] Used.

[0234] <Operation characteristics of light-emitting device 3> The operating characteristics of the fabricated light-emitting device 3 were measured. The measurements were performed at room temperature (25° C.). The event was held in a relaxed atmosphere.

[0235] The current density-luminance characteristics of the light-emitting device 3 are shown in FIG. 15, the voltage-luminance characteristics in FIG. 16, and the luminance-current efficiency in FIG. The rate characteristics are shown in FIG. 17 and the voltage-current characteristics are shown in FIG.

[0236] Also, 1000cd / m 2 The main initial characteristics of light-emitting devices in the vicinity are shown in Table 4 below. vinegar.

[0237] [Table 4]

[0238] In addition, 2.5 mA / cm2 was applied to the light-emitting device 3. 2Emission spectrum when current is applied at a current density of The emission spectrum of the light-emitting device is shown in FIG. The peak is near the peak of [Ir(ppy)2(mdppy It is suggested that this is due to the emission of

[0239] Here, the guest material (phosphorescent material) [Ir(ppy)2(mdppy The absorption spectrum of )] in dichloromethane solution is shown in Figure 23(A). An enlarged view of the absorption edge of each of the fluorescein fluorine-containing ... The T1 level (T G : Absorption of phosphorescent materials The T1 level derived from the absorption edge of the spectrum is 2.44 eV (= 509 nm). Therefore, in the light-emitting layer 913 of the light-emitting device 3 shown in this example, As an organic compound having a naphtho[2',1':4,5]furo[2,3-b]pyrazine skeleton, Using 8mDBtBPNfpr(II), a luminescent material with a T1 level of 2.5 eV or less was [Ir(ppy)2(mdppy)] is used as the ion exchange coefficient. The fact that the optical device 3 exhibited good luminous efficiency indicates that the optical device 3 has a configuration according to one embodiment of the present invention. In the emissive layer 913 of Device 3, the excited state of 8mDBtBPNfpr(II) was converted to [ This result is due to the increased efficiency of energy transfer to the It can be said that.

[0240] (Reference synthesis example 1) The organic compound used in Examples 1 and 2, 8-[(3'-dibenzothiophene-4- 2',1':4,5]furo[2,3-b]pyrazine The synthesis method of 8mDBtBPNfpr(II) is explained below. The structural formula of DBtBPNfpr(II) is shown below.

[0241] [ka]

[0242] <Step 1; 5-chloro-3-(1-methoxynaphthalen-2-yl)pyrazine-2- Synthesis of amines> First, 0.92 g of 3-bromo-5-chloropyrazine-2-amine and 1-methoxynaphthalene 0.96 g of 2-boronic acid, 11 mL of 2M aqueous sodium carbonate solution, and 22 mL of toluene were added. The contents of the flask were stirred under reduced pressure. After degassing, tetrakis(triphenylphosphine)palladium(0) (abbreviation 0.10 g of Pd(PPh3)4 was added, and the mixture was stirred at 110°C for 15 hours to react.

[0243] After a certain time had elapsed, extraction was performed with toluene. The desired pyrazine was obtained by purifying 1 by silica gel column chromatography using 1 as a developing solvent. The derivative was obtained (yellow-white solid, yield 0.97 g, 77%). Synthesis scheme of step 1 is shown in the following formula (a-1).

[0244] [ka]

[0245] Step 2: 8-chloronaphtho[2',1':4,5]furo[2,3-b]pyrazine Synthesis> Next, 5-chloro-3-(1-methoxynaphthalene-2-yl) 0.96 g of pyrazin-2-amine, 17 mL of dehydrated tetrahydrofuran, and 17 mL of glacial acetic acid The flask was cooled to -10°C and then nitrous acid was added. 1.2 mL of ert-butyl was added dropwise, and the mixture was stirred at -10°C for 1 hour and at 0°C for 3.5 hours. After the time had elapsed, 200 mL of water was added to the resulting suspension, and the suspension was filtered by suction to obtain the desired pipette. The radin derivative was obtained (yellow-white solid, 0.69 g, 81% yield). The scheme is shown in (a-2) below.

[0246] [ka]

[0247] Step 3: 8-(3-chlorophenyl)naphtho[2',1':4,5]furo[2,3 -b]Synthesis of pyrazine> Next, 8-chloronaphtho[2',1':4,5]furo[2,3-b ] Pyrazine 1.24g, 3-chlorophenylboronic acid 0.81g, 2M potassium carbonate in water Put 7.0 mL of the solution, 47 mL of toluene, and 4.7 mL of ethanol into a three-neck flask and The atmosphere in the flask was replaced with nitrogen. After degassing by stirring under reduced pressure, palladium acetate (II ) (abbreviation: Pd(OAc)2) 0.15g, triphenylphosphine 0.56g were added, The mixture was reacted at 90° C. for 11 hours with stirring.

[0248] After a certain time had passed, extraction with toluene was performed. The product was purified by column chromatography to obtain the desired pyrazine derivative (yellow-white solid). The synthesis scheme of step 3 is shown below in (a-3). .

[0249] [ka]

[0250] <Step 4: Synthesis of 8mDBtBPNfpr(II)> Furthermore, the 8-(3-chlorophenyl)naphtho[2',1':4,5 ]furo[2,3-b]pyrazine 1.12g, 3-(4-dibenzothiophene)phenylborate 1.69g ronic acid, 3.14g potassium phosphate, 0.91g tert-butyl alcohol g, 27 mL of diethylene glycol dimethyl ether (abbreviation: diglyme) was added to a three-port filter. The flask was then placed in a flask and the inside of the flask was replaced with nitrogen. The contents of the flask were degassed by stirring under reduced pressure, and then Palladium(II) acetate (abbreviation: Pd(OAc)2) 37 mg, di(1-adamantyl) Add 0.12 g of n-butylphosphine (abbreviation: CataCXium A) and heat at 140°C. The mixture was stirred at room temperature for 40.5 hours to react.

[0251] After a predetermined time had elapsed, the resulting suspension was filtered by suction and washed with water and ethanol. The body was dissolved in toluene and passed through a filter aid consisting of layers of Celite, alumina, and Celite. After filtering, the product was recrystallized from toluene to obtain the target product (yellowish white solid, yield 0.01%). .99g, 54% yield).

[0252] The resulting yellowish white solid (0.99 g) was purified by train sublimation. The purification conditions were a pressure of 2.7 Pa and argon gas at a flow rate of 10.5 mL / min. The solid was heated at 310° C. After purification by sublimation, the target yellowish white solid was obtained in an amount of 0.81 g and a yield of The synthesis scheme of step 4 is shown below in (a-4).

[0253] [ka]

[0254] The yellow-white solid obtained in step 4 was analyzed by nuclear magnetic resonance spectroscopy ( 1 H-NMR The analysis results are shown below. 1 The H-NMR chart is shown in Figure 20. In the reference synthesis example, the organic compound 8mDBtBPNfpr(II) was obtained. It was.

[0255] 1 H-NMR.δ(CDCl3):7.47-7.49(m,2H),7.60-7.6 2(m,2H),7.66-7.88(m,8H),7.91(d,1H),8.05( d,1H),8.13-8.14(m,2H),8.20-8.23(m,2H),8. 29(d,1H),8.48(s,1H),8.55(d,1H),8.91(s,1H ). [Explanation of symbols]

[0256] 101 First electrode 102 Second electrode 103 EL layer 103a, 103b EL layer 104 Charge generating layer 111, 111a, 111b Hole injection layer 112, 112a, 112b hole transport layer 113, 113a, 113b Light-emitting layer 114, 114a, 114b electron transport layer 115, 115a, 115b electron injection layer 200R, 200G, 200B optical distance 201 First Substrate 202 Transistor (FET) 203R, 203G, 203B, 203W Light Emitting Devices 204 EL layer 205 Second Board 206R, 206G, 206B Color Filters 206R', 206G', 206B' Color filters 207 First Electrode 208 Second Electrode 209 Black layer (black matrix) 210R, 210G conductive layer 301 First Substrate 302 Pixel section 303 Driver circuit section (source line driver circuit) 304a, 304b Drive circuit section (gate line drive circuit) 305 Sealing material 306 Second Board 307 Wiring 308 FPC 309 FET 310 FET 311 FET 312 FET 313 First electrode 314 Insulation 315 EL layer 316 Second Electrode 317 Light Emitting Devices 318 Space 900 Substrate 901 First electrode 902 EL layer 903 Second electrode 911 Hole injection layer 912 Hole transport layer 913 Emitting layer 914 Electron transport layer 915 Electron injection layer 4000 Lighting Equipment 4001 Board 4002 Light-emitting devices 4003 Substrate 4004 First electrode 4005 EL layer 4006 Second electrode 4007 Electrode 4008 Electrode 4009 Auxiliary wiring 4010 Insulation layer 4011 Sealing substrate 4012 Sealing material 4013 Desiccant 4015 Diffuser 4200 Lighting Equipment 4201 Substrate 4202 Light-emitting devices 4204 First electrode 4205 EL layer 4206 Second electrode 4207 Electrode 4208 Electrode 4209 Auxiliary wiring 4210 Insulating layer 4211 Sealing substrate 4212 Sealing material 4213 Barrier film 4214 Planarization film 4215 Diffuser 5101 Light 5102 Wheels 5103 Door 5104 Display section 5105 Handle 5106 Shift lever 5107 Seat 5108 Inner rear view mirror 5109 Windshield 7000 Chassis 7001 Display section 7002 2nd display section 7003 Speaker 7004 LED Lamp 7005 Operation key 7006 Connection terminal 7007 Sensor 7008 Microphone 7009 Switch 7010 Infrared port 7011 Recording medium reading unit 7012 Support part 7013 Earphones 7014 Antenna 7015 Shutter button 7016 Image receiving unit 7018 Stand 7020 Camera 7021 External connection part 7022, 7023 Operation buttons 7024 Connection terminal 7025 band, 7026 Microphone 7027 Time Icon 7028 Other Icons 7029 Sensor 7030 Speaker 7052, 7053, 7054 Information 9310 Mobile Information Terminal 9311 Display section 9312 Display area 9313 Hinge 9315 Case

Claims

1. A light-emitting layer is disposed between a pair of electrodes, the light-emitting layer contains an organic compound represented by general formula (G1) and a phosphorescent material, The phosphorescent material is an organometallic complex having a diazine skeleton, and has a T1 level (T Ｇ ) is 2.5 eV or less, The T1 level of the organic compound (T Ｈ ) and the T1 level of the phosphorescent material (T Ｇ ) satisfies the following formula (1): (However, T Ｇ indicates the T1 level derived from the absorption edge of the absorption spectrum of the phosphorescent material, and T Ｈ indicates the T1 level derived from the emission edge on the short wavelength side of the phosphorescence spectrum of the organic compound. 【number】 (In the formula, Q represents oxygen or sulfur. A represents a group having a molecular weight of 1000 or less. R １ ~R ６ each independently represents any one of hydrogen, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 7 carbon atoms, and a substituted or unsubstituted aryl group having 6 to 30 carbon atoms. [0010]

2. A light emitting device according to claim 1; A light emitting device having an FPC.

3. A light emitting device according to claim 2; An electronic device having at least one of a microphone, a camera, an operation button, an external connection unit, or a speaker.

4. A light emitting device according to claim 1; and at least one of a housing or a cover.

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