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 or a driving method. Composition of Matter. [Background technology]

[0002] A light-emitting device (also known as 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 LED technology, and is thin and lightweight, has high-speed response to input signals, Because of their low power consumption and other characteristics, displays that use 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 electrons injected from each electrode by applying a voltage between a pair of electrodes. The electrons and holes recombine in the EL layer, and the light-emitting material (organic compound) contained in the EL layer is excited. The excited state is then converted to a ground state, at which point light is emitted. In the singlet excited state (S * ) and triplet excited states (T * ) from the singlet excited state The emission from the triplet excited state is called fluorescence, and the emission from the triplet excited state is called phosphorescence. The statistical generation rate of these in * :T * It is believed that the ratio is 1:3. The emission spectrum obtained from a material is specific to that material, and different types of organic compounds By using compounds as luminescent materials, it is possible to obtain light-emitting devices with various luminescent colors. Cut.

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

[0005] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-188671 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] Therefore, in one aspect of the present invention, in the light-emitting layer of a light-emitting device, a host material is converted into a guest material. 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, in an emitting layer of a light-emitting device, a host material is converted into a guest material. In addition, in one embodiment of the present invention, a light-emitting device having 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 present invention to solve all of these problems. The above will be made clear from the description, 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 to use 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 By using a light-emitting material (including an organometallic complex) that satisfies the above requirement, This not only increases the efficiency of energy transfer to the guest material 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 including 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 skeleton. The present invention relates to a compound and a light-emitting device having an organometallic complex 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, T1 level (T G ) is a light-emitting device in which the 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 are each independently 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, or a substituted or unsubstituted carbon represents any one of aryl groups having 6 to 30 prime numbers.)

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

[0017]

number

[0018] In each of the above-mentioned structures, it is more preferable that the T1 level (T H ) and phosphorescence The T1 level of the 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 "light emitting device" 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 light emitting device is connected to a connector, such as an FPC (Flexible Printed Circuit) Switched Circuit) or TCP (Tape Carrier Packet 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 modules in which a light emitting diode (LED) is directly mounted. [Effects of the Invention]

[0021] According to one aspect of the present invention, in the light-emitting layer of a light-emitting device, a transition from a host material to a guest material is Not only does this improve energy transfer efficiency, but it also makes it possible to 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. The embodiment does not necessarily have to have all of these effects. , the specification, drawings, claims, etc., and It is possible to extract other effects from the claims and other statements. It is possible to provide a novel light emitting device that can improve the reliability of the light source. [Brief explanation of the drawings]

[0024] [Figure 1] 1(A) and 1(B) are diagrams showing the structure of a light-emitting device. [Figure 2] 2(A), 2(B), and 2(C) are diagrams illustrating the light emitting device. [Figure 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. [Figure 5] 5(A), 5(B), and 5(C) are diagrams illustrating electronic devices. [Figure 6] 6(A) and 6(B) are diagrams illustrating 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) shows the absorption spectrum of [Ir(dppm)2(acac)], and Fig. 21(B) shows 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). [Figure 23] Fig. 23(A) shows the absorption spectrum of [Ir(ppy)2(mdppy)]. Fig. 23(B) shows an enlarged view of the vicinity of the absorption edge of the absorption spectrum of [Ir(ppy)2(mdppy)]. DETAILED DESCRIPTION OF THE INVENTION

[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 any modifications thereof may be made without departing from the spirit and scope of the present invention. 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 those in the actual embodiment for ease of understanding. Therefore, the disclosed invention may not necessarily represent the actual position, size, range, etc. The position, size, range, etc. are not necessarily limited to those disclosed in the drawings, etc.

[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 according to one embodiment of the present invention will be described with reference to FIGS. 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. A functional layer such as an electron injection layer may be provided as appropriate.

[0029] The light-emitting layer is a layer containing a light-emitting substance (guest material) and also contains a host material. The light-emitting layer contains a plurality of organic compounds (for example, a first organic compound) that function as host materials. 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 ',1':4,5]furo[2,3-b]pyrazine-based organic compounds were used to As a material, a luminescent material (including organometallic complexes) whose T1 level satisfies a certain range. Preferably, by using a luminescent material whose T1 level is 2.5 eV or less, the excited state This can increase the efficiency of energy transfer from the host material to the guest material in the state.

[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, electron The injection layer 115 has a structure in which layers are stacked in order as a functional layer.

[0032] Another example of the structure of a light-emitting device is a 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 resonators (microcavities) can be formed between a pair of electrodes. Light-emitting devices and the like having improved optical properties as a result of this are also included in one aspect of the present invention. When a voltage is applied to 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 electrode has optical properties (transparent electrode, semi-transparent / semi-reflective electrode, 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 reflectance of the semi-transmissive / semi-reflective electrode for visible light is preferably 20% or more and 80% or less. The resistivity of these electrodes is 1×10 -2 Ωcm It is preferable to have the following:

[0034] In the light-emitting device according to one embodiment of the present invention, the first electrode 101 and the second electrode 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 resistivity of this electrode is 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 Metals such as yttrium (Y), neodymium (Nd), and alloys containing these in appropriate combinations are used. In addition, elements belonging to Group 1 or Group 2 of the periodic table that are not listed above can also be used. Elements (e.g., lithium (Li), cesium (Cs), calcium (Ca), strontium rare earth metals such as strontium (Sr), europium (Eu), ytterbium (Yb) and An alloy containing an appropriate combination of these, 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, into the EL layer 103. This layer facilitates injection 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 material, holes are generated in the organic compound. Therefore, quinodimethane derivatives and Electron-withdrawing groups (halogen groups and silyl groups) such as chloranil derivatives and hexaazatriphenylene derivatives 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 and the like 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 is preferred because it has a very high electron-accepting property. -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-cyclopropanetriylidenetris [2,3,4,5,6-pentafluorobenzeneacetonitrile] can be used. Cut.

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

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

[0042] In addition, poly(N-vinyl alcohol), which is a polymer compound (oligomer, dendrimer, polymer, etc.), Poly(4-vinyltriphenylamine) (abbreviation: P VTPA), poly[N-(4-{N'-[4-(4-diphenylamino)phenyl]phenyl]phenyl] (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) / poly(styrenesulfonic acid) Addition of 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 acceptor materials). In this case, a composite material containing an acceptor material can be used. Electrons are extracted from the hole transport material, generating holes in the hole injection layer 111, and the holes are transported to the hole transport layer 11 Holes are injected into the light-emitting layer 113 through the hole-injecting layer 111. Alternatively, the layer may be formed of a single layer of a composite material containing a metal oxide and an acceptor material (electron-accepting material). However, the hole transport material and the acceptor material (electron acceptor material) are stacked in separate layers. It may be formed in layers.

[0044] As for the hole transporting material, the hole transporting property at the square root of the electric field strength [V / cm] of 600 is Mobility is 1×10 -6 cm 2 A material having a hole mobility of 1 / Vs or more is preferred. Any substance other than these can be used as long as it has a higher hole transporting property than the above.

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

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

[0047] Furthermore, 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 Rubazole, 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) and others.

[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-carbazole) PCBBi1BP), 4-(1-naphthyl-3-yl)triphenylamine -4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBANB), 4,4'-di(1-naphthyl)-4''-(9-phenyl-9H-carbamoyl) 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'-bifluoren-2-amine (abbreviation: PCBASF), 3-[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9-phenyl Nylcarbazole (abbreviation: PCzPCA1), 3,6-bis[N-(9-phenylcarbazole)]

[0043] PCz PCA2), 3-[N-(1-naphthyl)-N-(9-phenylcarbazol-3-yl )amino]-9-phenylcarbazole (abbreviation: PCzPCN1), 3-[N-(4-di 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)phenyl Niline (abbreviation: YGA1BP), N,N'-bis[4-(carbazol-9-yl)phenyl] Nyl]-N,N'-diphenyl-9,9-dimethylfluorene-2,7-diamine (abbreviation :YGA2F), 4,4',4''-tris(carbazol-9-yl)triphenyl Min (abbreviated as TCTA) and others.

[0049] Other carbazole derivatives (compounds with 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-trimethyl- Tris[4-(N-carbazolyl)phenyl]benzene (abbreviation: TCPB), 9-[4-( 10-phenyl-9-anthracenyl)phenyl]-9H-carbazole (abbreviation: CzP A) etc.

[0050] Specific examples of the furan derivatives (compounds having a furan skeleton) include 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-phenyldibenzothiazolinone Compounds with a thiophene skeleton, such as thiophene (abbreviated as 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 phenyl}dibenzofuran (abbreviation: mmDBFFLBi-II), and the like.

[0051] Specific examples of the aromatic amine (a compound having an aromatic amine skeleton) include: ,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( abbreviation: BSPB), 4-phenyl-4'-(9-phenylfluoren-9-yl)triflate phenylamine (abbreviation: BPAFLP), 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) (abbreviated as 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 selected from the group consisting of the 4th group of the periodic table of elements. Oxides of metals belonging to groups 1 to 8 can be used. Specifically, molybdenum oxide , vanadium oxide, niobium oxide, tantalum oxide, chromium oxide, tungsten oxide, ma Among them, molybdenum oxide is particularly stable in the atmosphere. In addition, the organic acceptor described above is used. It is also possible to do so.

[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. The hole transport layer 112 contains a hole transport material. Therefore, the hole transport layer 112 is a layer containing holes that can be used in the hole injection layer 111. As the transporting material, the hole transporting material described above 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 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; ) in the light-emitting layer 113 of the light-emitting device according to one embodiment of the present invention. As a binder 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 fluorine-containing compound. The T1 level (T H : Emission of phosphorescence in the short wavelength region of the phosphorescence spectrum of organic compounds 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). T1 level (T H ) is the T1 level (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 this differs from the above in the aspect.) From this point of view, T H -T G is 0.3 It is more preferable that the value is equal to or less than 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 T G ) more preferably satisfies the following formula (2).

[0061]

number

[0062] By forming the light-emitting layer 113 in this manner, the energy from the host material to the guest material can be This results in a highly reliable light-emitting device with high energy transfer efficiency.

[0063] The T1 level (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 onset is used. On the ridgeline on the short wavelength side, draw a tangent line near the half-value of the peak on the shortest wavelength side, and is the wavelength at which the horizontal axis intersects with the T1 level (T H ) can be done.

[0064] In addition, the T1 level (T G ) is the absorption edge of the guest material's absorption spectrum. The absorption edge of the absorption spectrum is the ridge line on the longest wavelength side of the absorption spectrum. In this case, draw a tangent at the half-value of the peak or shoulder peak on the longest wavelength side. is the wavelength at the point where the tangent 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 fluorescent material. materials that emit phosphorescence (fluorescent materials), materials that exhibit thermally activated delayed fluorescence (phosphorescent materials), Thermally activated delayed fluorescence Fluorescence (TADF) materials and other light-emitting materials can be used. In one aspect of the present invention, as described above, the T1 level (T G ) within a certain range range (preferably, T 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, etc. are particularly preferred. A substance that emits light of a certain color can be used as appropriate. By having a light-emitting layer, a configuration that exhibits different luminescent colors (for example, luminescent colors that are complementary colors) can be obtained. In addition, one emitting layer may be made of different luminescent materials. A configuration having a plurality of these may also be used.

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

[0067] Examples of fluorescent materials 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)-4'-(10-phenyl-9-anthryl)triphenylamine (abbreviation Name: YGAPA), 4-(9H-carbazol-9-yl)-4'-(9,10-diphenyl N,9-diphenyl-2-anthryltriphenylamine (abbreviation: 2YGAPPA) 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'- 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 amine (abbreviation: 2PCAPA), N-[9,10-bis(1,1'-biphenyl-2-yl)] )-2-anthryl]-N,9-diphenyl-9H-carbazol-3-amine (abbreviation: 2PCABPhA), N-(9,10-diphenyl-2-anthryl)-N,N',N' -Triphenyl-1,4-phenylenediamine (abbreviation: 2DPAPA), N-[9,10 -bis(1,1'-biphenyl-2-yl)-2-anthryl]-N,N',N'-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-phenylanthracen-2-amine (abbreviation: 2YGABPhA), 9-Triphenylanthracen-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]quinolizidine] 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 (abbreviation: 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-4-ylidene}propanedinitrile (abbreviation: BisDCJTM), Phenyl-N,N'-(1,6-pyrene-diyl)bis[(6-phenylbenzo[b]naphthyl) 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). 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] Furthermore, examples of phosphorescent materials that can be used as guest materials for 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 Iridium(III) (abbreviation: [Ir(Mpt z)3]), tris[4-(3-biphenyl)-5-isopropyl-3-phenyl-4H -1,2,4-triazolato]iridium(III) (abbreviation: [Ir(iPrptz-3 b) Organometallic iridium complexes with a 4H-triazole skeleton, such as 3), and tris [3-methyl-1-(2-methylphenyl)-5-phenyl-1H-1,2,4-triazol- Zolato]iridium(III) (abbreviation: [Ir(Mptz1-mp)3]), tris(1 -methyl-5-phenyl-3-propyl-1H-1,2,4-triazolato)iridium (III) (abbreviation: [Ir(PrptZ1-Me)3]) 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-Me)3). Bis[2-(4',6'-difluorophenyl)pyridinato-N,C 2’ ]iridium( III) Tetrakis(1-pyrazolyl)borate (abbreviation: FIr6), bis[2-(4' ,6'-difluorophenyl)pyridinato-N,C 2’ ]Iridium(III) picolinate bis(2-[3',5'-bis(trifluoromethyl) fluoride] (abbreviation: FIrpic), Phenyl]pyridinato-N,C 2’}Iridium(III) picolinate (abbreviation: [Ir( CF3ppy)2(pic)]), bis[2-(4',6'-difluorophenyl)pyri[ Ginat-N,C 2’ ]Iridium(III) acetylacetonate (abbreviation: FIraca c) Organometallic iridates with phenylpyridine derivatives having electron-withdrawing groups as ligands These compounds exhibit blue phosphorescence, with wavelengths ranging from 440 nm to 5 It is a compound that has an emission peak at 20 nm.

[0071] Also, tris(4-methyl-6-phenylpyrimidinato)iridium(III) (abbreviation: [Ir(mppm)3]), tris(4-t-butyl-6-phenylpyrimidinato)yl Ir(tBuppm)3), (acetylacetonato)bis(Ir(tBuppm)3) (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)]) Organic metal iridium complexes and (acetylacetonato)bis(3,5-dimethyl-2-phenyl) Rupirazinato)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(benzyl) Tribenzo[h]quinolinato)iridium(III) (abbreviation: [Ir(bzq)3]), tris (2-phenylquinolinato-N,C 2’ ) Iridium(III) (abbreviation: [Ir(pq) 3]), bis(2-phenylquinolinato-N,C 2’ ) Iridium(III) acetylacetone Pyridine skeleton-containing compounds such as setonate (abbreviation: [Ir(pq)2(acac)]) In addition to organometallic iridium complexes, tris(acetylacetonato)(monophenanthroline)tetrahydrogen Rare earth metals such as rubium(III) (abbreviated as [Tb(acac)3(Phen)]) These are mainly compounds that exhibit green phosphorescence, with wavelengths ranging from 500 nm to 60 The emission peak is at 0 nm. is particularly preferred because it is remarkably excellent in reliability and luminous efficiency.

[0072] Also, (diisobutyrylmethanato)bis[4,6-bis(3-methylphenyl)pyrimidinyl] Nato]iridium(III) (abbreviation: [Ir(5mdppm)2(dibm)]), bis [4,6-bis(3-methylphenyl)pyrimidinato](dipivaloylmethanato)iridine Ir(III) (abbreviation: [Ir(5mdppm)2(dpm)]), bis[4,6-di( Naphthalen-1-yl)pyrimidinato](dipivaloylmethanato)iridium(III) Organogold compounds with pyrimidine skeletons, such as [Ir(d1npm)2(dpm)] iridium complexes of the genus acetylacetonatobis(2,3,5-triphenylpyrazine) Iridium(III) (abbreviation: [Ir(tppr)2(acac)]), bis(2, 3,5-triphenylpyrazinate)(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 organometallic iridium complexes with pyrazine skeletons such as Tris(1-phenylisoquinolinato-N,C 2’ ) Iridium(III) (abbreviation: [Ir (piq)3]), bis(1-phenylisoquinolinato-N,C 2’ ) Iridium (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) (Troline) europium(III) (abbreviation: [Eu(TTA)3(Phen)]) These are compounds that exhibit red phosphorescence and are The emission peak is between 100 nm and 700 nm. The di-nium complex emits 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) containing metals 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-trimethyl Triazine (abbreviation: PIC-TRZ), 2-{4-[3-(N-phenyl-9H-carbazo (carbazol-3-yl)-9H-carbazol-9-yl]phenyl}-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- phenyl)-4,5-diphenyl-1,2,4-triazole (abbreviation: PPZ-3 TPT), 3-(9,9-dimethyl-9H-acridin-10-yl)-9H-xanthene 9-(4-(9,9-dimethyl-9,10-dihydro-1,3-dimethyl-2,4 ... 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 and heterocyclic compounds having a π-electron deficient heteroaromatic ring may also be used.

[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, diazine skeleton (pyrimidine skeleton, pyrazine skeleton, pyrida skeleton) The benzophenone skeleton) and triazine skeleton are preferred because they are stable and reliable. Zofuropyrimidine skeleton, benzothienopyrimidine skeleton, benzofuropyrazine skeleton, benzo The 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 these skeletons because of its high reliability. The dibenzofuran skeleton is the most common, and the dibenzothiophene skeleton is the most common. The pyrrole skeleton includes an indole skeleton, a carbazole skeleton, 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 property of the π-electron-rich heteroaromatic ring and the electron-accepting property of the π-electron-deficient heteroaromatic ring are both enhanced. Since the energy difference between the S1 level and the T1 level becomes small, thermally activated delayed fluorescence can be obtained efficiently. In addition, a heteroaromatic ring such as a cyano group may be used instead of the π-electron deficient heteroaromatic ring. An aromatic ring having such an electron-withdrawing group bonded thereto may also 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. A compound having a boron-containing skeleton, a nitrile group such as benzonitrile or cyanobenzene, or a 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] TADF materials have a small difference between the S1 and T1 levels, and triple intersystem crossing occurs due to 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 doublet excited energy (reverse intersystem crossing), and efficiently convert the singlet excited state It is possible to generate triplet excitation energy and convert it into luminescence. .

[0084] In addition, exciplexes (exciplexes) 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 Draw a tangent at the tail of the graph, and the energy of the wavelength of the extrapolated line is taken 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 taken 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 S1 The T level of the host material is preferably higher than the S level of the TADF material. It is preferable that the T1 level is higher than that 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 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 silicon skeleton Using organometallic complexes with diazine skeletons (including pyrazine skeletons or pyrimidine skeletons) 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 skeleton has a high T1 of over 2.5 eV. Therefore, the T1 excitation energy is applied to luminescent materials with a T1 level of 2.5 eV or less. It is possible to move without deactivation. In addition, among naphthofuropyrazine skeletons, In particular, the naphtho[2',1':4,5]furo[2,3-b]pyrazine structure has been shown to be highly phosphorescent. Organometallic compounds with a diazine skeleton (including a pyrazine 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] The naphthofuropyrazine structure (naphtho[2',1':4,5]furo[2,3-b The organic compound having a pyrazine skeleton is an organic compound represented by the following general formula (G1): 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 are each independently hydrogen, a substituted or unsubstituted alkyl group having 1 to 6 carbon atoms, a substituted or an unsubstituted cycloalkyl group having 3 to 7 carbon atoms, or a substituted or unsubstituted carbon and any one of aryl groups having 6 to 30 carbon atoms.

[0091] Specific examples of the alkyl group having 1 to 6 carbon atoms in the general formula (G1) include methyl butyl, sec-butyl, isobutyl, ethyl, propyl, isopropyl, butyl, sec-butyl, isobutyl butyl group, pentyl group, isopentyl group, sec-pentyl group, tert-butyl group t-pentyl group, neopentyl group, hexyl group, isohexyl group, 3-methylpentyl group , 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 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 include an octyl group.

[0093] Specific examples of the aryl group having 6 to 30 carbon atoms in the 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 include an anthracenyl group and a fluoranthenyl group.

[0094] In addition, the above structure (naphthofuropyrazine skeleton (naphtho[2',1':4,5]furo[2, 3-b]pyrazine skeleton) as a host material, and the T1 level is 2.5 eV or less, and 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 a certain organic compound and the T1 level of the luminescent material (guest material) is 0.2 eV. It is preferable that the energy of the naphthofuropyrazine skeleton is 0.4 eV or more. The to[2',1':4,5]furo[2,3-b]pyrazine skeleton has a high T1 of over 2.5 eV. Therefore, the T1 excitation energy is applied to luminescent materials with a T1 level of 2.5 eV or less. It is possible to move without deactivation. In addition, among naphthofuropyrazine skeletons, In particular, naphtho[2',1':4,5]furo[2,3-b]pyrazine skeleton is a diazine skeleton (pyrazine overlap with the MLCT absorption band of organometallic complexes having a hydroxyl or pyrimidine skeleton The large difference in the energy transfer efficiency makes these complexes stable and excitable. Therefore, the durability of the light-emitting device is improved, and high reliability is achieved. An organometallic complex having a rhodidine or pyrimidine skeleton is used as a light-emitting material. In the light-emitting layer 113 having the 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 guest material is within an appropriate range, i.e., 0.2 eV or more and 0.4 eV or more. 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 the following structural formulas (100) to (101). The formula is shown in (123).

[0096] [ka]

[0097] [ka]

[0098] [ka]

[0099] Other 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 ( Abbreviation: BPAFLP), 4-phenyl-3'-(9-phenylfluoren-9-yl)trimethylsilyl 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)triphenyl Phenylamine (abbreviation: PCBNBB), 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]spiro-9,9'-bifluoren-2-amine (abbreviated as 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-thiazolinone) 2,8-diphenyltriyltri(dibenzothiophene) (abbreviation: DBT3P-II) -4-[4-(9-phenyl-9H-fluoren-9-yl)phenyl]dibenzothiof fluorene (abbreviation: DBTFLP-III), 4-[4-(9-phenyl-9H-fluorene- 9-yl)phenyl]-6-phenyldibenzothiophene (abbreviation: DBTFLP-IV) Compounds with a thiophene skeleton, 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 (abbreviated :mmDBFFLBi-II) and other compounds having a furan skeleton. Among these, compounds with aromatic amine skeletons and compounds with carbazole skeletons are highly reliable. In addition, the hole transporting property is high, which contributes to reducing the driving voltage, and is therefore preferable. The organic compounds listed above as examples of the second organic compound can also be used.

[0101] In addition, as an electron transport material, the electron transfer rate at a 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 1 / Vs or more is preferred, and examples thereof include the following: 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)benzyl. 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 include metal complexes such as 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 Rubazole (abbreviation: CO11), 2,2',2''-(1,3,5-benzenetriyl) Tris(1-phenyl-1H-benzimidazole) (abbreviation: TPBI), 2-[3-( Dibenzothiophen-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)- phenyl]dibenzo[f,h]quinoxaline (abbreviation: 2mDBTPDBq-II), 2-[3'-(dibenzothiophen-4-yl)biphenyl-3-yl]dibenzo[f, h]quinoxaline (abbreviation: 2mDBTBPDBq-II), 2-[3'-(9H-carba [f,h]quinoxaline (abbreviation: 2 Dibenzoquinoxaline derivatives such as 4,6-bis[3-(phenanthroline) (Tren-9-yl)phenyl]pyrimidine (abbreviation: 4,6mPnP2Pm), 4,6-biphenyl bis[3-(4-dibenzothienyl)phenyl]pyrimidine (abbreviation: 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)]naphtho To[1',2':4,5]furo[3,2-d]pyrimidine (abbreviation: 8mDBtBPNfp m), 8-[(2,2'-binaphthalen)-6-yl]-4-[3-(dibenzothiophene 8(βN-4-yl)phenyl-[1]benzofuro[3,2-d]pyrimidine (abbreviation: 8(βN 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 (abbreviated as 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-[(2,3-b)-yl]phenanthro[9',10':4,5]furo[2,3-b]pyrazine pyrazine derivatives such as mDBtBPPnfpr, and heterocyclic compounds having a diazine skeleton Things 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 a pyridine skeleton. Examples of heterocyclic compounds include:

[0106] Among the above, heterocyclic compounds having a diazine skeleton and heterocyclic compounds having a pyridine skeleton are preferred. Materials having good reliability are preferred. In particular, those having a diazine (pyrimidine or pyrazine) skeleton are preferred. 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 luminescent centers. By transferring energy to the material, the luminous 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 substance is used as the light source. Therefore, 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 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: is preferable in combination with luminescent materials (fluorescent materials, phosphorescent materials) (Some overlap with the above) The following organic compounds are included:

[0109] When the luminescent material is a fluorescent luminescent material, an organic compound that is preferably combined with the fluorescent luminescent material Examples include anthracene derivatives, tetracene derivatives, phenanthrene derivatives, and pyrene derivatives. condensed polycyclic aromatic compounds such as chrysene derivatives, dibenzo[g,p]chrysene derivatives, etc. It can be obtained.

[0110] Specific examples of organic compounds that are preferably combined with fluorescent substances include 9-phenyl 3-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole ( Abbreviation: PCzPA), 3,6-diphenyl-9-[4-(10-phenyl-9-anthracene phenyl]-9H-carbazole (abbreviation: DPCzPA), 3-[4-(1-naphthyl)phenyl]-9H-carbazole 9,10-[(2-phenyl)-phenyl]-9-phenyl-9H-carbazole (abbreviation: PCPN), 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-dimethacrylate 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-anthylenediamine]-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 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'- Diphenylphenanthrene (abbreviation: DPNS2), 1,3,5-tri(1-pyrenyl)benzyl tetracene (abbreviation: TPB3), 5,12-diphenyltetracene, 5,12-bis(biphenyl) (2-yl)tetracene.

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

[0112] By using this structure, the energy transfer from the exciplex to the luminescent material, Ex Using TET (Exciplex-Triplet Energy Transfer) It is possible to efficiently obtain light emission with high excitation power. A compound that easily forms an electron-transporting complex and easily accepts holes (hole transport material) is preferable. It is particularly preferable to combine it with a compound that readily accepts electrons (electron transporting material).

[0113] When the light-emitting substance is a phosphorescent material, a preferable combination with the phosphorescent material is an organic compound. Compounds (host materials, assist materials) include aromatic amines, carbazole derivatives, diamines, and Benzothiophene derivatives, dibenzofuran derivatives, zinc and aluminum metal complexes, Quinoxadiazole derivatives, triazole derivatives, benzimidazole derivatives, quinoxaline Derivatives, dibenzoquinoxaline derivatives, pyrimidine derivatives, pyrazine derivatives, triazine 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(naphthalen-2-yl)-4,7-diphenyl 1,10-phenanthroline (abbreviation: NBphen), 2-[3-(dibenzothiophene) (4-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-carbazol-1-yl)methyl] 2CzPDBq-I II), 7-[3-(dibenzothiophen-4-yl)phenyl]dibenzo[f,h]ky Noxaline (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-(phenanthrene-9-yl)phenyl]pyrimidine (abbreviated :4,6mPnP2Pm), 4,6-bis[3-(4-dibenzothienyl)phenyl]pi Rimidine (abbreviation: 4,6mDBTP2Pm-II), 4,6-bis[3-(9H-carba pyrimidines such as 4,6mCzP2Pm) derivatives, 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: Triazine derivatives such as mPCCzPTzn-02, 3,5-bis[3-(9H-carba (35DCzPPy), 1,3,5-triphenyl-9-ol 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 (vacuum deposition, coating, printing, etc.) can be used appropriately.

[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. Between the electron transport layer 114 and the second electrode 102, an electron injection layer 114 (described later) is provided. The electron transport layer 114 may have an electron transporting 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 containing an alkali metal or an alkaline earth metal. In addition, when these metals, metal salts, metal oxides, or metal complexes are contained, electron transport The electron transport layer 114 may be present in any region of the layer 114. For example, In the case where the light-emitting layer 113 has a fluorine-containing compound, the fluorine-containing compound may be present in any of the layers. The electron transport layer 114 (in the case of a laminated structure, the layer in contact with the light-emitting layer) The LUMO level of the electron transporting material is higher 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. 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 electron transport material having a HOMO level of -6.0 eV or more. 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 x10 -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 preferred that the compound contains a cyclic skeleton and a heterocyclic skeleton.

[0120] The organic compound used in the electron transport layer 114 is a compound having a furan ring in a furodiazine skeleton and an aromatic ring. Organic compounds with condensed structures, metal complexes with quinoline skeletons, benzoquinoline skeletons a metal complex having an oxazole skeleton, a metal complex having a thiazole skeleton, In addition to compounds such as oxadiazole derivatives, triazole derivatives, imidazole derivatives, oxadiazole derivatives, azole derivatives, thiazole derivatives, phenanthroline derivatives, quinoline-containing chiral quinone derivatives Quinoline derivatives, benzoquinoline derivatives, quinoxaline derivatives, dibenzoquinoxaline derivatives Compounds, pyridine derivatives, bipyridine derivatives, pyrimidine derivatives, and other nitrogen-containing heteroaromatics Highly electron-transporting materials such as π-electron-deficient heteroaromatic compounds including π-electron-deficient heteroaromatic compounds (electron-transporting materials) 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 can be used. Other substances can be used as long as they have a high transporting property. (114, 114a, 114b) can function as a single layer, but can also be stacked as needed with two or more layers. 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: For this purpose, the following substances may be used as needed.

[0122] Metals include alkali metals, alkaline earth metals, and rare earth metals. Examples of elements 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. Specific examples include Li2O, Examples include Na2O, Cs2O, MgO, and CaO.

[0125] The metal complex may comprise 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 compounds). The 8-quinolinolato structure is a substituted or This refers to the structure of unsubstituted 8-quinolinol in which the proton of the -OH group has been removed.

[0126] Therefore, the metal complexes having the alkali metal or alkaline earth metal include 8- 8-(quinolinolato)lithium, a lithium complex containing a quinolinolato structure. Lithium (abbreviation: Liq), a sodium complex containing a ligand containing an 8-quinolinolato structure. 8-(quinolinolato) sodium (abbreviation: Naq), a compound containing the 8-quinolinolato structure 8-(quinolinolato)potassium (abbreviation: Kq), a potassium complex with the ligand A magnesium complex containing a quinolinolato structure, (8-quinolinolato) Magnesium (abbreviated as Mgq2) and other metal complexes have the 8-quinolinolato structure. Zinc complexes with ligands containing quinolinolato (8-quinolinolato) zinc (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 of the material used in the electron injection layer 115 are 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 contains lithium, cesium, lithium fluoride (LiF), Cesium fluoride (CsF), calcium fluoride (CaF2), 8-(hydroxyquinolinol) tri)lithium (abbreviation: Liq), 2-(2-pyridyl)phenolatolithium (abbreviation: Li PP), 2-(2-pyridyl)-3-pyridinolatolithium (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 These compounds can also be used. Metalloid compounds can be used.

[0128] In addition, as shown in FIG. 1(B), the two EL layers (103a, 103b) By providing a charge generating layer 104 between the electrodes, a structure in which multiple EL layers are stacked between a pair of electrodes is obtained. In this embodiment, the structure shown in FIG. ) described in the above, the hole injection layer (111), the hole transport layer (112), the light emitting layer (113), the electron The transport layer (114) and the electron injection layer (115) are formed by the hole injection layer 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> 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 101 and the second electrode (cathode) 102, the first electrode 102, which is the anode, Electrons are injected into the EL layer 103a on the cathode side, and the EL layer 103a on the cathode side is The charge generation layer 104 has a function of injecting holes into the hole transport material. Even in a structure where an acceptor is added (P-type layer), electrons are donated to the electron transport material. 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 generation layer 104, a structure in which an electron acceptor is added to a hole transport material (P-type layer) In this case, the material shown in this embodiment mode can be used as the hole transporting material. The electron acceptor is 7,7,8,8-tetracyano-2,3,5,6-tetrafluoroethylene. Examples include 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 generation layer 104, an electron donor is added to the electron transport 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 Groups 2 and 13 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 electron injection buffer layer and the P-type layer, interaction between the electron injection buffer layer and the P-type layer is prevented. The electron relay layer has the function of smoothly transferring electrons. The LUMO level of the electron transport material contained 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 is -5.0 eV or higher, preferably -5.0 eV or higher to -3. The electron transport material used in the electron relay layer is preferably a lid Cyanine-based materials or metal complexes with metal-oxygen bonds and aromatic ligands can be used. preferable.

[0133] The electron injection buffer layer may contain alkali metals, alkaline earth metals, rare earth metals, and their derivatives. Compounds of alkali metal compounds (oxides such as lithium oxide, halides, lithium carbonate 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 high electron injection properties, such as the following.

[0134] In addition, when the electron injection buffer layer is formed containing an electron transporting material and an electron donating 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) or compounds of rare earth metals (including oxides, halides, carbonates) )), as well as tetrathianaphthacene (abbreviation: TTN), nickelocene, decamethylnickelocene, As the electron transporting material, organic compounds such as benzene can also be used. The electron transport layer can be formed using the same material as that of the electron transport layer.

[0135] Although FIG. 1B shows a configuration in which two EL layers 103 are stacked, different EL layers may be 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 can also be used in place of the electron injection layer. In this case, the electron injection buffer layer, electron relay layer, and 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 Substrates, metal substrates, stainless steel substrates, substrates with stainless steel foil, Tungsten substrate, substrate with tungsten foil, flexible substrate, lamination film Examples of the substrate include paper, 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, etc. Flexible substrates, lamination films, etc. Examples of base films include polyethylene terephthalate (PET), polyethylene terephthalate (PE ... Plastics such as polyethylene 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 film and paper.

[0139] Note that the light-emitting device shown in this embodiment mode can be manufactured by a vacuum process such as evaporation or a spin process. Solution processes such as the ink-jet method and the vapor deposition method can be used. In this case, sputtering, ion plating, ion beam deposition, and molecular beam deposition are used. , physical vapor deposition (PVD) methods such as vacuum deposition, chemical vapor deposition (CVD) methods, 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 methods (dip coating, die coating, bar coating, spin coating, spray coating) printing methods (inkjet method, screen printing method, offset printing method, etc.), printing), flexography (relief printing), gravure, microcontact, nanoimprint The film can be formed by a method such as a lithography method.

[0140] The EL layers (103, 103a, 103b) of the light-emitting device shown in this embodiment are The functional layers (hole injection layers (111, 111a, 111b), hole transport layers (112, 113)) 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) 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 shall be 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 type having a plurality of light-emitting devices (203R, 203G, 203B, 20 3W) has a common EL layer 204 and each light-emitting device is individually controlled according to the light-emitting color of each light-emitting device. The device has a microcavity structure with an tuned optical distance between the electrodes. The light emitted from the layer 204 is filtered through a color filter (206R, 206G, 206B).

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

[0144] In addition, in FIG. 2(A), 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, and the light emitting device When the device 203W is a white light emitting device, the light emitting device 203W is 03R is set so 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 specific wavelength ranges of visible light to pass through and block specific wavelength ranges. Therefore, as shown in FIG. 2(A), the filter overlaps with the light-emitting device 203R. By providing a color filter 206R that passes only the red wavelength region at a position corresponding to the Red light can be emitted from the optical device 203R. By providing a color filter 206G that passes only the green wavelength region at a position corresponding to the wavelength of the light, Green light can be obtained from the optical device 203G. By providing a color filter 206B that transmits only the blue wavelength region at a position Blue light can be obtained from the optical device 203B. However, the light-emitting device 203W has the following characteristics: White light can be obtained without using a color filter. A black layer (black matrix) 209 may be provided on the edge 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. 2(A), a structure (top emission type) in which light is extracted to the second substrate 205 side is used. The light emitting device is shown, but as shown in FIG. 2(C), the first substrate on which the FET 202 is formed is 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 closer to the first substrate 201 than the other 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 depending on the emission color of the light emitting device.

[0148] By adopting the above-described 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 shall be 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 arc type or a passive matrix type can be manufactured. An active matrix light-emitting device combines a light-emitting device and a transistor (FET). Therefore, it is possible to use a passive matrix light emitting device, an active matrix light emitting device, Any of these types of 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. 3A. The active matrix light emitting device is 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 sealing material 305. It is sealed between the plate 306 .

[0154] Furthermore, lead wiring 307 is provided on the first substrate 301. is electrically connected to the FPC 308, which is an external input terminal. An external signal (for example, a video signal, a clock signal) is input to the driving circuit unit (303, 304a, 304b). The FPC308 also transmits signals such as lock signals, start signals, and reset signals, as well as electrical potentials. A printed wiring board (PWB) may be attached. 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, 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 that each pixel has is not particularly limited, and It can be provided 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 structure may be a Tom-gate type or the like.

[0158] The semiconductor crystals 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 crystalline semiconductor (microcrystalline semiconductor, Any of polycrystalline semiconductors, single-crystalline semiconductors, and semiconductors having crystalline regions in part may be used. Note that the use of a crystalline semiconductor can suppress the deterioration of transistor characteristics. This is preferable because it is possible to

[0159] In addition, these semiconductors include, for example, elements of Group 14, compound semiconductors, and oxide semiconductors. , organic semiconductors, etc. can be used. Typically, semiconductors containing silicon, gallium, 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, it may be formed by a CMOS circuit including N-type and P-type transistors. Alternatively, 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 insulating material 314 to be improved.

[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. Has.

[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 may be made of an external material. 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 of FIG. 3(B), In the unit 302, a plurality of light emitting devices are arranged in a matrix. The element 302 has three light emitting devices that can emit light of three kinds (R, G, B). In addition, three types of light emitting devices (R, In addition to light-emitting devices that can emit light in the colors white (W), yellow (Y), A light-emitting device that emits light of blue, magenta (M), cyan (C), or the like may be formed. For example, a light-emitting device that emits three types of light (R, G, B) can emit several of the above types of light. By adding a light-emitting device that can be used in a variety of applications, it is possible to improve color purity and reduce power consumption. In addition, full color display is possible when combined with a color filter. The light emitting device may be a light emitting device. Blue (B), cyan (C), magenta (M), yellow (Y), etc. can be used.

[0165] FETs (309, 310, 311, 312) on the first substrate 301 and light-emitting devices 31 7 is a process for bonding the second substrate 306 and the first substrate 301 together with a sealing material 305. As a result, the space 3 surrounded by the first substrate 301, the second substrate 306, and the sealing material 305 is The space 318 is filled with an inert gas (nitrogen, argon, etc.). ) or organic matter (including the 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 as described in other embodiments as appropriate. In addition to glass and quartz substrates, FRP (Fiber-Reinforced Plastics) is also used as the substrate. d Plastics), PVF (Polyvinyl Fluoride), Polyester or Acrylic A plastic substrate made of a glass frit or the like can be used as a sealing material. When using a glass substrate, the first substrate 301 and the second substrate 306 are preferably made of glass from the viewpoint of adhesiveness. Preferably it is a substrate.

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

[0168] In addition, when an active matrix light emitting device is formed on a flexible substrate, The FET and the light emitting device may be formed directly, 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. For example, inorganic films such as a tungsten film and a silicon oxide film may be laminated, or a material such as polyimide may be used. A flexible substrate may be formed on the substrate. In addition to the substrates that can be used, paper substrates, cellophane substrates, aramid film substrates, polyimide film substrates, Film substrate, cloth substrate (natural fibers (silk, cotton, linen), synthetic fibers (nylon, polyurethane, polyester) polyester) or recycled fibers (acetate, cupra, rayon, recycled polyester) The substrates include leather and rubber. This allows for superior durability and heat resistance, as well as lighter weight and thinner construction.

[0169] The light-emitting devices in the active matrix light-emitting device are driven by the light-emitting devices. A structure that emits light in pulses (for example, using frequencies such as kHz or MHz) and is used for display. The light-emitting device formed using the organic compound has excellent frequency characteristics. Therefore, the driving time of the light emitting device can be shortened, and power consumption can be reduced. In addition, heat generation is suppressed as the driving time is shortened, 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] (Fourth embodiment) 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 light-emitting devices with chairs. 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 FIGS. 4A to 4E includes a housing 7000, a display portion 7001, a speaker, and a 7003, LED lamp 7004, operation key 7005 (power switch or operation switch ), connection terminal 7006, sensor 7007 (force, displacement, position, velocity, acceleration, angular velocity , rotation speed, distance, light, liquid, magnetism, temperature, chemicals, sound, time, hardness, electric field, current, voltage , including the ability to measure power, radiation, flow rate, humidity, gradient, vibration, odor, or infrared rays. ), a microphone 7008, etc.

[0173] FIG. 4(A) shows a mobile computer, which includes the above-mentioned components, a switch 7009, a red It may have an outside line port 7010, etc.

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

[0175] Figure 4(C) is a digital camera with a TV receiving function, and in addition to the above, it also 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 portion 7001. Here, information 7052, information 7053, and information 7054 are respectively For example, the user may have a mobile information terminal in his / her breast pocket. When the terminal is stored, information 7053 is displayed in a position that can be observed from above the mobile information terminal. Users can check the display without taking the mobile information terminal out of their pocket. and can decide, for example, whether to answer the call or not.

[0177] FIG. 4E shows a portable information terminal (including a smartphone), in which a display unit 7 is mounted in 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 used. 70. The example shows information 7051 shown in a dashed rectangle on the display unit 7001. Examples of information 7051 include email, SNS, Notifications of incoming calls, etc., subject lines of emails and SNS messages, sender names, date and time, battery status, etc. The remaining battery power, antenna reception strength, etc. Or, 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 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 device 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 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, Functions such as calendar, date or time display, various software (programs) It has the functions of controlling processing by wireless communication, and It has the function of connecting to a data network, and the function of transmitting or receiving various data using wireless communication. 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 multiple display units, One display mainly displays image information, and the other mainly displays text information. or the ability to display images that take parallax into account on multiple displays to create a three-dimensional image. Furthermore, in an electronic device 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), It should be noted that the functions shown in FIGS. 4(A) to 4(F) can be implemented by the following methods. The functions that the electronic device shown in the figure can have are not limited to these, and it may have various functions. can be done.

[0180] FIG. 4(G) shows a wristwatch-type mobile information terminal that can be used as a smart watch, for example. This wristwatch-type portable 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 , a sensor 7029, a speaker 7030, etc. 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 calling is possible by communicating with a wireless headset. The connection terminal 7024 allows data to be transmitted to and from other information terminals. Charging can also be performed by wireless power supply.

[0181] The display unit 7001 mounted on the housing 7000, which also serves as a bezel, has a non-rectangular display area. The display unit 7001 has an icon 7027 that indicates 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, Functions such as calendar, date or time display, various software (programs) It has the functions of controlling processing by wireless communication, and It has the function of connecting to a data network, and the function of transmitting or receiving various data using wireless communication. The function of reading out the program or data recorded on the recording medium and displaying it on the display unit. It can have functions such as:

[0183] In addition, a speaker, a sensor (force, displacement, position, velocity, acceleration, angular velocity) Degrees, rotation speed, distance, light, liquid, magnetism, temperature, chemical substances, sound, time, hardness, electric field, current, electricity Includes functions to measure pressure, power, radiation, flow rate, humidity, gradient, vibration, odor or infrared. ), 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, folding devices as shown in FIGS. 5(A) to 5(C) are also available. A foldable mobile information terminal is an example. Figure 5(A) shows a mobile information terminal in an unfolded state. 9310. Also, in FIG. 5(B), the 5C shows the mobile information terminal 9310 in the process of changing to the other state. The portable information terminal 9310 is shown in a folded state. When unfolded, it has a seamless, large display area, allowing you to see the entire display at a glance. 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 space 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 931 can be used for the display unit 9311. 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 is a display area where information icons and frequently used apps and programs are displayed. You can display shortcuts for programs, check information, and launch apps. It can be done smoothly.

[0187] Also, 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 provided integrally with the automobile. The exterior lights 5101 (including the rear of the car), the wheels 5102, the doors 5103. The inner display unit 5104, the steering wheel 5105, the shift lever 5106, the seat 510 7. Can be applied to inner rearview mirrors 5108, windshields 5109, etc. It may also be applied to other glass window parts.

[0188] In this manner, an electronic device or an automobile to which the light-emitting device of 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 all 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 according to 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 an uneven surface 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 an uneven surface as shown in FIG. This can improve the extraction efficiency of light generated in the chair 4002.

[0195] A lighting device 4200 in FIG. 7B has 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. It 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 4206 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 formed between the sealing substrate 4211 and the light-emitting device 4202. 7B, the sealing substrate 4211 may have a recess and a groove. 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: direct ceiling mounted and recessed ceiling lights. Such a lighting device is constructed by combining a light-emitting device with a housing and a cover.

[0199] Other applications include footlights that can illuminate the floor and increase safety underfoot. It is also possible to use a foot lamp in a bedroom, on stairs, or in a hallway. In this case, 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-type lighting device (sheet-type 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, and it can be used on curved walls and enclosures.

[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 installed in a room. By applying a light-emitting device, which is a part of the design, we aim 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 described in this embodiment mode may be used in appropriate combination with structures described in other embodiments. It is possible. [Example]

[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 will be explained. A comparative light-emitting device 2 was fabricated and the two were compared. The chair structure is shown in Figure 8, and the specific configuration is shown in Table 1. The chemical formula is shown below:

[0205] [Table 1]

[0206] [ka]

[0207] <Fabrication of light-emitting devices> The light-emitting device shown in this example has a first electrode formed on a substrate 900 as shown in FIG. On the layer 901, a hole injection layer 911, a hole transport layer 912, a light emitting layer 913, an electron transport layer 914, and an electron A structure in which 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 / 2 mm. , indium tin oxide containing silicon oxide (ITSO) was deposited by sputtering to a thickness of 70 nm. The film was formed to a thickness of .

[0209] Here, as a pretreatment, the surface of the substrate is washed with water, baked at 200°C for 1 hour, and then UV- The treatment was carried out for 370 seconds. -4 Vacuum steaming with the inside pressure reduced to about Pa The substrate was introduced into the vacuum deposition apparatus, and 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 x 10 -4 After reducing the pressure to 100 Pa, 1,3,5-tri(dibenzothiophene-4 -yl)benzene (abbreviation: DBT3P-II) and molybdenum oxide to form DBT3P-II : 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 BBiF) was vapor deposited 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 light-emitting device 1, light-emitting layer 913 is 8-[(3'-dibenzothiophene-4-yl)-2-(4-methylphenyl)-2-propanediol]. (I)biphenyl-3-yl]naphtho[2',1':4,5]furo[2,3-b]pyrazine (abbreviation: 8mDBtBPNfpr(II)) and PCBBiF, as well as the guest material ( 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 film thickness was 40 nm. For 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 ) as [Ir(dppm)2(acac)], and the weight ratio was 12mDBtBPPn fpr:PCBBiF:[Ir(dppm)2(acac)]=0.75:0.25:0 The film was co-evaporated to a thickness of 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 formed of 8mDBtBPNfpr(II) with a thickness of 1000 nm. 2,9-bis(naphthalen-2-yl)-4,7-diphenyl-1,10- Phenanthroline (NBphen) was deposited in layers to a thickness of 15 nm. In the case of comparative light-emitting device 2, the film thickness of 12mDBtBPPnfpr was 25 The film was formed by sequential deposition so that the thickness of the NBphen was 15 nm.

[0216] Next, an electron injection layer 915 was formed on the electron transport layer 914. The electron injection layer 915 was made of a fluoride Lithium (LiF) was used and was formed by vapor deposition to a film 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 film was formed by vapor deposition so as to have a thickness of 200 nm. Thus, the second electrode 903 functions as a cathode.

[0218] By 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 electron transport layer 913, the electron injection layer 915, and the electron transport layer 914 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] <Operating 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. Figure 9 shows the voltage-luminance characteristics, Figure 10 shows the luminance-current efficiency characteristics, Figure 11 shows the voltage-current characteristics, 12 respectively.

[0221] Also, 1000 cd / 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 values ​​shown in FIGS. 9 to 12 or Table 2. In terms of characteristics, it was found that the device exhibited better luminous efficiency than the comparative light-emitting device 2.

[0224] Furthermore, the light-emitting device 1 and the comparative light-emitting device 2 were 2 Current at a current density of The emission spectrum when the light emitting device 1 and the light emitting device 2 were flowed 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 around 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 conducted on the light-emitting device 1 and the comparative light-emitting device 2. The results of the experiment are shown in Figure 14. In Figure 14, the vertical axis represents the normalized value when the initial luminance is set to 100%. The horizontal axis shows the brightness (%), and the horizontal axis shows 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) [Ir(dppm)2(acac )] in dichloromethane solution is shown in Figure 21(A). An enlarged view of the absorption edge of each of the fluorescein-based fluorescein ... 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), phosphorescence emission with a T1 level of 2.5 eV or less was observed. As a substance, the T1 level is 2.22 eV (from 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 in light-emitting device 1, [Ir(dppm)2(acac)]. It is.

[0227] Therefore, the light emitting device 1 of this example has better initial characteristics 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 can be said to be a result of the fact that

[0228] In addition, in Figure 22(A), the naphtho[2',1':4,5]furo[2,3-b]pyrazine skeleton is 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 Using RAM HR-PL (Horiba Ltd.), 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. Therefore, T H -T G is 0.30 eV, and the value of 0.1 eV≦ T H -T G The condition of ≦0.4 eV is met. [Example]

[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 measurements of the characteristics are shown below.

[0230] The element structure of the light-emitting device 3 fabricated in this example was the same as that shown in FIG. 8 in Example 1. The specific structure of each layer that makes up the device 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. 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, the guest material (phosphorescent material) is [2-(4-methyl -5-phenyl-2-pyridinyl-κN)phenyl-κC]bis[2-(2-pyridinyl [-κN)phenyl-κC]iridium (abbreviation: [Ir(ppy)2(mdppy)]) Used.

[0234] <Operating characteristics of light-emitting device 3> The operating characteristics of the fabricated light-emitting device 3 were measured. The measurements were carried out 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. 17. The rate characteristics are shown in Figure 17, and the voltage-current characteristics are shown in Figure 18.

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

[0237] [Table 4]

[0238] In addition, 2.5 mA / cm 2The emission spectrum when a current is applied at a current density of The emission spectrum of the light-emitting device is shown in Figure 19. As shown in Figure 19, the emission spectrum of the light-emitting device is 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 )] in dichloromethane solution is shown in Figure 23(A). An enlarged view of the absorption edge of each of the fluorescein-based fluorescein ... 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 obtained. Therefore, the present invention uses [Ir(ppy)2(mdppy)] as the 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 [Ir(ppy)2(mdppy)]. It can be said that this is the case.

[0240] (Reference synthesis example 1) The organic compound used in Examples 1 and 2, 8-[(3'-dibenzothiophene-4- (yl)biphenyl-3-yl)naphtho[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 benzophenone-2-boronic acid, 11 mL of 2 M aqueous sodium carbonate solution, and 22 mL of toluene were added. The contents were placed in a three-necked flask equipped with a reflux condenser, and the inside of the flask was replaced with nitrogen. After degassing, tetrakis(triphenylphosphine)palladium(0) (abbreviated 0.10 g of Pd(PPh3)4 was added, and the mixture was stirred at 110°C for 15 hours to allow the reaction to proceed.

[0243] After a predetermined time had passed, extraction with toluene was carried out. Purify 1 by silica gel column chromatography using 1 as a developing solvent to obtain the desired pyrazine. 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-methoxynaphthalen-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 the inside of the flask was replaced with nitrogen. 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 passed, 200 mL of water was added to the resulting suspension, and the suspension was filtered by suction to obtain the target pipette. The azithrazine derivative was obtained (yellowish white solid, 0.69 g, yield 81%). 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 aqueous potassium carbonate solution Put 7.0 mL of the solution, 47 mL of toluene, and 4.7 mL of ethanol into a three-neck flask. The atmosphere in the flask was replaced with nitrogen. After degassing by stirring under reduced pressure, palladium acetate (II ) (abbreviation: Pd(OAc)2) 0.15 g, triphenylphosphine 0.56 g were added, The mixture was stirred at 90°C for 11 hours to react.

[0248] After a certain time had passed, extraction with toluene was carried out. The product was purified by gel column chromatography to obtain the desired pyrazine derivative (a 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 of uronic acid, 3.14g of potassium phosphate tripotassium, 0.91g of tert-butyl alcohol g, and 27 mL of diethylene glycol dimethyl ether (abbreviation: diglyme) was poured into a three-port tube. 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) 0.12 g of n-butylphosphine (abbreviation: CataCXium A) was added and the mixture was heated at 140°C. The mixture was stirred at room temperature for 40.5 hours to react.

[0251] After a predetermined time had passed, 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 target product was obtained by recrystallization with toluene (yellowish white solid, yield 0.01%). 0.99g, 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 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. The synthesis scheme for 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 generation 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 substrate 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 substrate 307 Wiring 308 FPC 309 FET 310 FET 311 FET 312 FET 313 First electrode 314 Insulators 315 EL layer 316 Second electrode 317 Light-emitting devices 318 Space 900 boards 901 First electrode 902 EL layer 903 Second electrode 911 Hole injection layer 912 Hole transport layer 913 Light-emitting layer 914 Electron transport layer 915 Electron injection layer 4000 lighting equipment 4001 board 4002 Light-emitting devices 4003 board 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 Circuit Board 4202 Light-emitting devices 4204 First electrode 4205 EL layer 4206 Second electrode 4207 Electrode 4208 Electrode 4209 Auxiliary wiring 4210 Insulation 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 rearview 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 chassis

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 (T Ｈ ) and the T1 level (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】 (wherein Q represents oxygen or sulfur, A represents a group having a molecular weight of 1000 or less, and 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. [Equation 1]

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

3. The 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 part, 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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