Light emitting device

Abstract

An object is to provide a light-emitting element with high emission efficiency by providing a novel fluorene derivative.SOLUTION: The fluorene derivative is represented by general formula (G1). Wherein J, k, m, and n are 0 or 1, provided that at least one of J and k is 1. ) SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to a fluorene derivative, a light-emitting element, a light-emitting device, an electronic device, and a lighting device. . [Background technology]

[0002] In recent years, electroluminescence has been used The basic structure of these light-emitting devices is a pair of A layer containing a light-emitting substance is sandwiched between the electrodes. This allows light emission from the luminescent substance to be obtained.

[0003] These light-emitting elements are self-luminous, so the pixels are more visible than those of LCDs. It has the advantage of being simple and does not require a backlight, making it suitable for use as a flat panel display element. Furthermore, such a light-emitting element can be manufactured to be thin and lightweight. Another major advantage is that it has an extremely fast response time.

[0004] These light-emitting elements can be formed in a film shape, making it possible to form elements with a large area. By forming this, it is possible to easily obtain a surface light emission. This is a feature that is difficult to obtain with point light sources such as D or linear light sources such as fluorescent lamps. It is also highly useful as a surface light source that can be applied to lighting, etc.

[0005] The light-emitting element that utilizes electroluminescence uses an organic compound as the light-emitting substance. They can be broadly classified according to whether they are organic or inorganic compounds, but there are also those that use organic compounds as luminescent materials. In the case of organic EL, when a voltage is applied to the light-emitting element, electrons and holes are emitted from a pair of electrodes. The electrons (holes) are injected into the layers containing the light-emitting organic compounds, and a current flows. These electrons are released from the excited state, where both electrons and holes are generated in the emissive organic molecules. Light is emitted when the carriers (electrons and holes) recombine and return to the ground state.

[0006] Due to this mechanism, such a light-emitting element is called a current-excited light-emitting element. The types of excited states that organic compounds form are singlet excited states and triplet excited states. Light emitted from the singlet excited state is called fluorescence, and light emitted from the triplet excited state is called phosphorescence. It's been discovered.

[0007] In addition to the light emission caused by the recombination of carriers excited by current, Another method is when energy is transferred to another organic compound, causing the organic compound to become excited and emit light. This is because, in general, in organic EL, the luminescent material is dispersed (doped) in the luminescent layer. The material to be dispersed is called the host, and the material being dispersed is called the dopant. This is because when the organic molecules that you want to emit light are concentrated at high concentrations, stacking interactions occur, resulting in poor luminescence efficiency. In order to eliminate this problem, the organic molecule is doped into the host. This increases efficiency by suppressing stacking. The excitation energy is transferred from the excited host to the dopant, causing the dopant to emit light. do.

[0008] This excitation energy transfer must be from a higher excitation energy to a lower energy. Therefore, a host material with a high excited state is desirable.

[0009] In addition, organic EL is composed of multiple layers, and a carrier transport layer is set between the light-emitting layer and the electrode. One of the reasons for this is that the excitation energy in the light-emitting layer is transferred to the electrode. This is to prevent the light from being quenched by the transfer of energy. The adjacent carrier transport layer is also designed to prevent the excitation energy of the light-emitting layer from being transferred. The carrier transport layer is made of a material with higher excitation energy (exciton blocking material) than the light-emitting layer. desirable.

[0010] In organic EL, a carrier injection layer and a carrier transport layer are provided between the light-emitting layer and the electrode. Another reason is to adjust the carrier injection barrier between adjacent layers. This allows for more efficient recombination in the light-emitting layer.

[0011] Regarding such light-emitting devices, there are material-dependent issues in improving the device characteristics. To overcome these problems, improvements to device structures and material development are being carried out (for example, (See Patent Document 1). [Prior art documents] [Patent documents]

[0012] [Patent Document 1] International Publication No. 08 / 062636 Summary of the Invention [Problem to be solved by the invention]

[0013] One embodiment of the present invention provides a novel fluorene derivative as a substance with a high hole-transporting property. Furthermore, by applying the novel fluorene derivative to a light-emitting element, It is an object of one embodiment of the present invention to provide a light-emitting element with high emission efficiency. The present invention aims to provide a light-emitting device, an electronic device, and a lighting device that are low in voltage and power consumption. It shall be one. [Means for solving the problem]

[0014] One embodiment of the present invention is a fluorene derivative represented by the following general formula (G1).

[0015] [ka] (In the formula, R 1 ~R 8 are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a substituted or an unsubstituted phenyl group, or a substituted or unsubstituted biphenyl group. , α 1 ~α 4 each independently represents a substituted or unsubstituted arylene group having 6 to 12 carbon atoms; Also, Ar 1 , Ar 2 are each independently a ring having 6 to 1 carbon atoms. 3 represents any of the aryl groups represented by Ar 3 is an alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted alkyl group. represents an unsubstituted aryl group having 6 to 12 carbon atoms; J, k, m, and n each independently represent 0 or or 1, provided that at least one of J and k is 1.)

[0016] In the above structure, R in general formula (G1) 1 ~R 8 are each independently structured as follows: It is characterized by being any one of the compounds represented by structural formula (R-1) to structural formula (R-9).

[0017] [ka]

[0018] In the above structure, α in general formula (G1) 1 ~α 4 are each independently represented by the structural formula It is characterized by being any one of the compounds represented by structural formulas (α-1) to (α-3).

[0019] [ka]

[0020] In the above structure, Ar in general formula (G1) 1 , Ar 2 are independently constructed It is any one of the structural formulas (Ar-1) to (Ar-6), and Ar 3 is the structural formula It is characterized by being any one of the compounds represented by structural formulas (Ar3-1) to (Ar3-8).

[0021] [ka]

[0022] [ka]

[0023] Another embodiment of the present invention is a compound represented by the following structural formula (101), (151), or (118). It is characterized by being any one of the above.

[0024] [ka]

[0025] [ka]

[0026] [ka]

[0027] Another embodiment of the present invention is a light-emitting element having an EL layer between a pair of electrodes, The light-emitting device has at least a light-emitting layer and a hole-transporting layer, and the hole-transporting layer contains the above-described fluorene derivative. It is characterized by including.

[0028] Furthermore, one embodiment of the present invention is characterized in that the light-emitting element described above is used. Furthermore, a light emitting device is provided, which is characterized by being formed using the light emitting device described above. The present invention also provides a lighting device formed using the light-emitting device described above.

[0029] Further, one embodiment of a light-emitting device of the present invention includes a light-emitting element and a control element for controlling light emission of the light-emitting element. In this specification, the light emitting device includes an image display device, a light emitting device, a The panel also includes a connector, e.g., FP C (Flexible printed circuit) or TAB (Tape Automated Bonding tape or TCP (Tape Carrier) Modules with a printed circuit board (r Package) attached, TAB tape or TCP A module with a wiring board or a light emitting element with COG (Chip On Glass) s) All modules in which ICs (integrated circuits) are directly mounted using this method are also included in the light-emitting device. Let's say.

[0030] Further, electronic devices using one embodiment of the light-emitting device of the present invention as a display portion are also included in the scope of the present invention. Therefore, one embodiment of an electronic device of the present invention has a display portion, and the display portion is The present invention is characterized by including a light emitting device.

[0031] Furthermore, a lighting device using one embodiment of the light-emitting device of the present invention is also included in the scope of the present invention. Therefore, one aspect of the lighting device of the present invention is characterized by including the above-mentioned light-emitting device. . [Effects of the Invention]

[0032] The fluorene derivative of the present invention exhibits high hole transport properties and is therefore mainly used in the EL layer of a light-emitting element. The fluorene derivative of the present invention can be used in a hole transport layer constituting the hole transport layer. By forming a light emitting element using the conductive layer, a light emitting element with high luminous efficiency can be formed. can.

[0033] Furthermore, by using this light-emitting element, a light-emitting device with low power consumption and low driving voltage can be realized. , electronic devices, and lighting devices can be obtained. [Brief explanation of the drawings]

[0034] [Figure 1] 1A and 1B are diagrams illustrating light-emitting elements. [Figure 2] 1A and 1B are diagrams illustrating light-emitting elements. [Figure 3] 1A and 1B are diagrams illustrating light-emitting elements. [Figure 4] 1A and 1B illustrate a light-emitting device. [Figure 5] 1A and 1B illustrate a light-emitting device. [Figure 6] 1A to 1C illustrate electronic devices. [Figure 7] 1A to 1C illustrate electronic devices. [Figure 8] 1A and 1B are diagrams illustrating a lighting device. [Figure 9] 1A and 1B are diagrams illustrating a lighting device. [Figure 10] 1 shows a 1H NMR chart of 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine. [Figure 11] FIG. 1 shows the absorption spectrum of 4-phenyl-4′-(9-phenylfluoren-9-yl)triphenylamine. [Figure 12] FIG. 1 shows the emission spectrum of 4-phenyl-4′-(9-phenylfluoren-9-yl)triphenylamine. [Figure 13] FIG. 1 shows the results of CV measurement of 4-phenyl-4′-(9-phenylfluoren-9-yl)triphenylamine. [Figure 14] 1 shows a 1H NMR chart of 4-phenyl-4'-[4-(9-phenylfluoren-9-yl)phenyl]triphenylamine. [Figure 15] FIG. 1 shows the absorption spectrum of 4-phenyl-4′-[4-(9-phenylfluoren-9-yl)phenyl]triphenylamine. [Figure 16] FIG. 1 shows the emission spectrum of 4-phenyl-4′-[4-(9-phenylfluoren-9-yl)phenyl]triphenylamine. [Figure 17] FIG. 1 shows the results of CV measurement of 4-phenyl-4′-[4-(9-phenylfluoren-9-yl)phenyl]triphenylamine. [Figure 18] 1A to 1C are diagrams illustrating light-emitting elements according to an embodiment. [Figure 19] FIG. 10 shows current density-luminance characteristics of the comparative light-emitting element 1 and the light-emitting element 2. [Figure 20] FIG. 10 shows voltage-luminance characteristics of the comparative light-emitting element 1 and the light-emitting element 2. [Figure 21] FIG. 10 shows luminance-current efficiency characteristics of the comparative light-emitting element 1 and the light-emitting element 2. [Figure 22] FIG. 10 is a graph showing current density-luminance characteristics of Light-emitting element 3. [Figure 23] FIG. 10 is a graph showing voltage-luminance characteristics of the light-emitting element 3. [Figure 24] FIG. 10 shows luminance-current efficiency characteristics of Light-emitting Element 3. [Figure 25] FIG. 10 shows the results of a reliability test on the light-emitting element 3. [Figure 26] FIG. 10 is a graph showing current density-luminance characteristics of Light-emitting Elements 4 and 5. [Figure 27] FIG. 10 shows voltage-luminance characteristics of Light-emitting Elements 4 and 5. [Figure 28] FIG. 10 shows luminance-current efficiency characteristics of Light-emitting Elements 4 and 5. [Figure 29] 10 shows the results of reliability tests on the light-emitting elements 4 and 5. FIG. [Figure 30] 10 shows current density-luminance characteristics of the light-emitting element 6 and the comparative light-emitting element 7. FIG. [Figure 31] FIG. 10 shows voltage-luminance characteristics of the light-emitting element 6 and the comparative light-emitting element 7. [Figure 32] FIG. 10 shows luminance-current efficiency characteristics of the light-emitting element 6 and the comparative light-emitting element 7. [Figure 33] FIG. 10 shows emission spectra of the light-emitting element 6 and the comparative light-emitting element 7. [Figure 34] 10 is a graph showing current density-luminance characteristics of light-emitting elements 8 to 10. FIG. [Figure 35] 10 is a graph showing voltage-luminance characteristics of light-emitting elements 8 to 10. FIG. [Figure 36] FIG. 10 is a graph showing luminance-current efficiency characteristics of Light-emitting Elements 8 to 10. [Figure 37] FIG. 10 shows the results of reliability tests on the light-emitting elements 8 to 10. [Figure 38] FIG. 10 shows current density-luminance characteristics of the light-emitting element 11 and the comparative light-emitting element 12. [Figure 39] FIG. 10 shows voltage-luminance characteristics of the light-emitting element 11 and the comparative light-emitting element 12. [Figure 40] FIG. 10 shows luminance-current efficiency characteristics of the light-emitting element 11 and the comparative light-emitting element 12. [Figure 41] FIG. 10 shows emission spectra of the light-emitting element 11 and the comparative light-emitting element 12. [Figure 42] FIG. 10 is a graph showing current density-luminance characteristics of the light-emitting element 13. [Figure 43] FIG. 10 is a graph showing voltage-luminance characteristics of the light-emitting element 13. [Figure 44] FIG. 10 shows luminance-current efficiency characteristics of the light-emitting element 13. [Figure 45]1 shows a 1H NMR chart of 4-phenyl-3'-(9-phenylfluoren-9-yl)triphenylamine. [Figure 46] FIG. 1 shows the absorption spectrum of 4-phenyl-3′-(9-phenylfluoren-9-yl)triphenylamine. [Figure 47] FIG. 1 shows the emission spectrum of 4-phenyl-3′-(9-phenylfluoren-9-yl)triphenylamine. [Figure 48] FIG. 10 shows current density-luminance characteristics of the light-emitting element 14 and the comparative light-emitting element 15. [Figure 49] FIG. 10 shows voltage-luminance characteristics of the light-emitting element 14 and the comparative light-emitting element 15. [Figure 50] FIG. 10 shows luminance-current efficiency characteristics of the light-emitting element 14 and the comparative light-emitting element 15. DETAILED DESCRIPTION OF THE INVENTION

[0035] Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. The present invention is not limited to the above description, and the embodiments and details thereof may be modified without departing from the spirit and scope of the present invention. It will be readily apparent to those skilled in the art that various modifications can be made to the above. The present invention should not be construed as being limited to the description of the embodiments.

[0036] (Embodiment 1) In this embodiment, a fluorene derivative which is one embodiment of the present invention will be described.

[0037] The fluorene derivative according to one embodiment of the present invention is a fluorene derivative represented by general formula (G1): It is the body.

[0038] [ka]

[0039] (In the formula, R 1 ~R8 are each independently a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, or a substituted or an unsubstituted phenyl group, or a substituted or unsubstituted biphenyl group. , α 1 ~α 4 each independently represents a substituted or unsubstituted arylene group having 6 to 12 carbon atoms; Also, Ar 1 , Ar 2 are each independently a ring having 6 to 1 carbon atoms. 3 represents any of the aryl groups represented by Ar 3 is an alkyl group having 1 to 6 carbon atoms, or a substituted or unsubstituted alkyl group. represents an unsubstituted aryl group having 6 to 12 carbon atoms; J, k, m, and n each independently represent 0 or or 1, provided that at least one of J and k is 1.)

[0040] In addition, R 1 ~R 8 , α 1 ~α 4 , Ar 1 , Ar 2 , Ar 3 When has a substituent, the substituent The substituents include alkyl groups such as methyl, ethyl, propyl, pentyl, and hexyl groups. Examples of the alkyl group include aryl groups such as phenyl, biphenyl, and naphthyl. For example, a methylphenyl group, a dimethylphenyl group, a t tert-butylphenyl group, di-tert-butylphenyl group, etc. The substituents may be linked to each other to form a ring (for example, a biphenyl group may be 1 Ma Or Ar 2 The fluorenyl group of the fluorenyl group forms a ring to form a 9,9'-spirofluorenyl group. Examples include a cyclohexyl group in which a hexyl group forms a ring.

[0041] In addition, when an alkyl group is used in the general formula (G1), the solubility in organic solvents is improved. Therefore, when using this material to create a device using a wet method, the alkyl group The use of certain materials makes it easier to fabricate the element, and is therefore preferable.

[0042] In general formula (G1), R 1 ~R 8 is a hydrogen atom, a methyl group, an ethyl group, or a propyl group. alkyl groups such as pentyl and hexyl groups, substituted or unsubstituted phenyl groups, substituted or unsubstituted phenyl groups, is an aryl group such as an unsubstituted biphenyl group. ) to (R-9) are examples.

[0043] [ka]

[0044] In general formula (G1), α 1 ~α 4 is a substituted or unsubstituted phenylene group. Specific examples include groups represented by structural formulas (α-1) to (α-3).

[0045] [ka]

[0046] In general formula (G1), Ar 1 , Ar 2 represents a substituted or unsubstituted phenyl group, a substituted or unsubstituted phenyl group, Unsubstituted biphenyl group, substituted or unsubstituted naphthyl group, substituted or unsubstituted fluorenyl group and aryl groups such as substituted or unsubstituted spirofluorenyl groups. Examples of the groups include those shown in structural formulas (Ar-1) to (Ar-6). , the biphenyl group is Ar 1or Ar 2 The fluorenyl group of the 9,9'-spiro group forms a ring. This resulted in a fluorenyl group.

[0047] In this case, when a fused ring group is used, as in (Ar-2) or (Ar-3), the carrier transport property is improved. In this case, the condensed ring group and the nitrogen atom are preferably bonded to each other. Ru α 1 or α 2 When is 1, the band gap (Bg) of the molecule is kept wider, which is preferable. In addition, structures using sigma bonds, such as (Ar-5), have a structure where the bond from the nitrogen atom The conjugation is difficult to spread, and the Bg and T1 levels are high. Therefore, this material is suitable for emitting shorter wavelengths. Used in optical devices as a material for a layer adjacent to a light-emitting layer or as a doping material for the light-emitting layer It is considered that this is possible, and is therefore preferred. In addition, (Ar-2), (Ar-3) and (Ar-4) The use of a rigid condensed ring group with a large molecular weight such as Superior and desirable

[0048] [ka]

[0049] In general formula (G1), Ar 3 is a methyl group, an ethyl group, a propyl group, a pentyl group, alkyl groups such as hexyl groups, substituted or unsubstituted phenyl groups, substituted or unsubstituted biphenyl groups, Specifically, examples of the structural formula (Ar3-1) to the structural formula (Ar3-2) include aryl groups such as phenyl groups. Examples include groups shown in (Ar3-8).

[0050] [ka]

[0051] Specific examples of the fluorene derivatives represented by the general formula (G1) include those represented by the structural formulas (100) to (101). The fluorene derivatives shown in structural formula (123), structural formula (150) to structural formula (173) are listed below. However, the present invention is not limited to these.

[0052] [ka]

[0053] [ka]

[0054] [ka]

[0055] [ka]

[0056] [ka]

[0057] [ka]

[0058] [ka]

[0059] [ka]

[0060] As a method for synthesizing the fluorene derivative according to one embodiment of the present invention, various reactions can be applied. For example, by carrying out the synthesis reaction shown below, the compound represented by general formula (G1) can be obtained. A fluorene derivative according to one embodiment of the present invention can be synthesized. The synthesis method of the fluorene derivative is not limited to the following synthesis method.

[0061] <Method 1 for synthesizing fluorene derivative represented by general formula (G1)> As shown in Scheme (A-1), 1-halogenated biphenyl derivative (a1) is converted into lithiated biphenyl derivative (a2). After conversion to a benzoyl derivative (a2), the resulting compound is deoxygenated to a benzoyl derivative (a3). By hydrogenation, the halogenated arylfluorene derivative (a3) ​​is obtained.

[0062] [ka]

[0063] In addition, in the scheme (A-1), an aryl compound having a halogen group is activated. Then, it is reacted with a benzoyl derivative to form a phenol derivative, and then an acid is added to remove the hydroxyl group. This allows the conversion to a fluorene derivative.

[0064] Examples of activation include lithiation with alkyllithium reagents and activated mag. The reaction of converting the alkyl lithium to a Grignard reagent with nesium can be used. -butyllithium, tert-butyllithium, methyllithium, etc. As a solvent, ethers such as diethyl ether or Tetrahydrofuran (THF) can be used, and an anhydrous solvent is used.

[0065] As shown in Scheme (A-2), the halogenated arene derivative (a4) and the aryl Coupling with amine derivative (a5) gives diarylamine derivative (a6). is obtained.

[0066] [ka]

[0067] Then, as shown in Scheme (A-3), a halogenated arylfluorene derivative (a3 ) and diarylamine derivative (a6), to obtain the compound of the general formula (G1 ) is obtained.

[0068] [ka]

[0069] In the above schemes (A-1) to (A-3), X 1 , X 2 represents a halogen and is reactive From the viewpoint of the height of the ion, it preferably represents bromine or iodine, more preferably iodine.

[0070] In the schemes (A-2) and (A-3), an aryl compound having a halogen group is and aryl compounds having amines (primary arylamine compounds, secondary arylamine compounds) There are various reaction conditions for the coupling reaction with the compound, but one example is in the presence of a base. A synthesis method using a metal catalyst can be applied.

[0071] In the schemes (A-2) and (A-3), the Hartwig-Buchwald reaction The metal catalyst can be a palladium catalyst. As the radium catalyst, a mixture of a palladium complex and its ligand can be used. Palladium complexes include bis(dibenzylideneacetone)palladium(0), palladium acetate, Examples of the ligand include tri(tert-butyl)phosphine(II). Sphines, tri(n-hexyl)phosphine, tricyclohexylphosphine, 1 , 1-bis(diphenylphosphino)ferrocene (abbreviation: DPPF), etc. In addition, examples of substances that can be used as bases include sodium tert-butoxide, etc. Examples of the base include organic bases such as potassium carbonate and inorganic bases such as potassium carbonate. It is preferable to carry out the reaction in a liquid, and examples of the solvent that can be used include toluene, xylene, and benzene. However, the catalyst and its ligand, base, The solvent is not limited to these. The reaction is not carried out in an inert atmosphere such as nitrogen or argon. It is preferable to carry out the process below.

[0072] In the schemes (A-2) and (A-3), the Ullmann reaction is used. A copper catalyst can be used as the metal catalyst, and copper (I) iodide or copper (II) acetate can be used. In addition, examples of substances that can be used as bases include inorganic bases such as potassium carbonate. The reaction is preferably carried out in a solution. The solvent used is 1,3-dimethyl-3,4,5,6-tetrahydro-2(1H)pyrimidinone. Examples of suitable solvents include diisopropyl alcohol (DMPU), toluene, xylene, and benzene. The catalysts, bases, and solvents that can be used are not limited to these. It is preferable to carry out the reaction in an inert atmosphere such as argon.

[0073] In the Ullmann reaction, a reaction temperature of 100°C or higher can achieve the desired product in a shorter time and with a higher yield. Therefore, it is preferable to use a solvent with a high boiling point such as DMPU or xylene. In addition, the reaction temperature is more preferably 150°C or higher, and therefore, DMPU is more preferably used. is used.

[0074] <Method 2 for synthesizing fluorene derivative represented by general formula (G1)> For example, as shown in scheme (B-1), a halogenated fluorene derivative (a3) By coupling with the arylamine derivative (a5), the fluorenyl diaryl The benzoylamine derivative (b1) is obtained.

[0075] [ka]

[0076] Then, as shown in Scheme (B-2), a fluorenyl diarylamine derivative (b 1) and a halogenated arene derivative (a4) are coupled to form the compound of the general formula ( A fluorene derivative represented by G1) is obtained.

[0077] [ka]

[0078] In the above schemes (B-1) and (B-2), X 2 , X 3 represents a halogen and is reactive From the viewpoint of the height of the ion, it preferably represents bromine or iodine, more preferably iodine.

[0079] In the schemes (B-1) and (B-2), an aryl compound having a halogen group and , aryl compounds having amines (primary arylamine compounds, secondary arylamine compounds) There are various reaction conditions for the coupling reaction with methyltrimethylsilyl group, but one example is in the presence of a base. A synthesis method using a metal catalyst can be applied.

[0080] In the schemes (B-1) and (B-2), ) as well as the Hartwig-Buchwald and Ullmann reactions can be used.

[0081] <Method 3 for synthesizing fluorene derivative represented by general formula (G1)> Furthermore, for example, as shown in scheme (C-1), a halogenated arylfluorene derivative (c1) is lithiated or converted into a Grignard reagent, and then reacted with an organic boronic acid to give This gives a fluorenylarylboronic acid derivative (c2) (wherein J represents 1).

[0082] [ka]

[0083] As shown in scheme (C-2), the triarylamine derivative (c3) can be converted to a halogen atom. By converting the halogenated triarylamine derivative (c4), a halogenated triarylamine derivative (c4) can be obtained.

[0084] [ka]

[0085] Then, as shown in Scheme (C-3), a fluorenylarylboronic acid derivative (c 2) is coupled with a halogenated triarylamine derivative (c4) to obtain the above A fluorene derivative represented by the following general formula (G1) is obtained.

[0086] [ka]

[0087] In the schemes (C-2) and (C-3), k represents 1.

[0088] In the above schemes (C-1) to (C-3), X 4 , X 5 represents a halogen and is reactive From the viewpoint of the height of the ion, it preferably represents bromine or iodine, more preferably iodine.

[0089] In addition, in the scheme (C-1), an aryl compound having a halogen group can be converted into a boronic acid group. There are various conditions for the reaction to produce aryl compounds having (or organoboron groups). Keem Medium R 1 ~R 8 represents hydrogen or an alkyl group.

[0090] For example, after lithiation with an alkyllithium reagent, boron reagent is added to produce a boron compound. The alkyllithium reagent can be n-butylated or organoborated. As a boron reagent, trimethyl borate, methyl lithium, etc. can be used. The solvent used may be diethyl ether or isopropyl borate. Any ether or tetrahydrofuran (THF) can be used, and anhydrous solvents are used. In addition, instead of the lithiated reagent, activated magnesium was used to prepare the Grignard reagent. You can also be there.

[0091] In addition, the halogenation reaction in the scheme (C-2) can be carried out under various conditions. A reaction using a halogenating agent in a solvent can be used. -Bromosuccinimide (NBS) and N-iodosuccinimide (NIS), bromine, iodine The halogenating agent can be a bromide, potassium iodide, etc. Furthermore, when iodide is used as the halogenating agent, the resulting When the target compound is used as a raw material for the next reaction (the iodine-substituted portion is more active), In scheme (C-2), k represents 1. The halogenation occurs specifically at the para position relative to the amine.

[0092] In the scheme (C-3), an aryl compound having a halogen group and a boronic acid are The coupling reaction with aryl compounds (arylboronic acids) has various reaction conditions. As an example, a synthesis method using a metal catalyst in the presence of a base can be applied. do.

[0093] In the scheme (C-3), the Suzuki-Miyaura reaction is used. As the catalyst, a palladium catalyst can be used. A mixture of the complex and its ligand can be used. Radium(II), tetrakis(triphenylphosphine)palladium(0), bis(triphenylphosphine)palladium(0), (triphenylphosphine)palladium(II) dichloride, etc. Examples of the phosphine include tri(ortho-tolyl)phosphine, triphenylphosphine, and tricyclophosphine. Further, the substances that can be used as the base include cyclohexylphosphine. Examples include organic bases such as sodium tert-butoxide and inorganic bases such as potassium carbonate. The reaction is preferably carried out in a solution, and the solvents that can be used include Examples include a mixed solvent of toluene and water, a mixed solvent of toluene and alcohol such as ethanol, and water. solvents, mixed solvents of xylene and water, mixed solvents of xylene and alcohol such as ethanol and water, Mixed solvents of benzene and water, mixed solvents of alcohols such as benzene and ethanol, ethylene Examples include a mixed solvent of water and an ether such as glycol dimethyl ether. The catalyst, base, and solvent that can be used are not limited to these. In this system, instead of arylboronic acids, organoboron compounds of aryl derivatives and Aryl aluminum, aryl zirconium, aryl zinc, aryl tin compounds, etc. The reaction is preferably carried out in an inert atmosphere such as nitrogen or argon.

[0094] (Embodiment 2) In this embodiment, the fluorene derivative which is one embodiment of the present invention described in Embodiment 1 is A light-emitting element formed by using the compound as a hole transport layer will be described.

[0095] The light-emitting element in this embodiment has a first electrode functioning as an anode and a second electrode functioning as a cathode. a second electrode formed on the first electrode, and an EL layer provided between the first electrode and the second electrode. In the light emitting element of this embodiment, the first electrode has a higher current density than the second electrode. When a voltage is applied to each of them so that the potential becomes higher, light emission is obtained.

[0096] In addition, the EL layer of the light-emitting element in this embodiment is formed by a first layer (hole injection layer) from the first electrode side. the first layer (hole transport layer), the third layer (light emitting layer), the fourth layer (electron transport layer), the fifth ... The layer (electron injection layer) is included.

[0097] The structure of the light-emitting element in this embodiment will be described with reference to Fig. 1. The substrate 101 is a light-emitting The substrate 101 is used as a support for the element. For example, glass, quartz, plastic, etc. etc. can be used.

[0098] The substrate 101 is a light-emitting device that is a product using a light-emitting element according to one embodiment of the present invention. It may remain in the device or electronic device, but it will not remain in the final product and it is not included in the manufacturing process of the light-emitting element. It may have only the function of a support in the method.

[0099] The first electrode 102 formed on the substrate 101 is made of a material having a large work function (specifically, 4. 0 eV or more) metals, alloys, electrically conductive compounds, and mixtures thereof can be used. Specifically, for example, indium oxide-tin oxide (ITO) is preferable. in Oxide), indium oxide-tin oxide containing silicon or silicon oxide, oxide Indium zinc oxide (IZO), tungsten oxide Indium oxide containing zinc oxide and indium oxide are also included. (Pt), Nickel (Ni), Tungsten (W), Chromium (Cr), Molybdenum (Mo ), iron (Fe), cobalt (Co), copper (Cu), palladium (Pd), titanium (Ti) or nitrides of metal materials (for example, titanium nitride), etc. In this case, the first layer 111 of the EL layer 103 formed in contact with the first electrode 102 is The first electrode 102 is made of a composite material that is easy to inject holes into regardless of the work function. Therefore, the electrode material can be made of a material such as a metal, an alloy, an electrically conductive compound, or and mixtures thereof, including other elements belonging to Groups 1 and 2 of the Periodic Table Any known material can be used.

[0100] These materials are usually deposited by sputtering. Zinc oxide (IZO) is a target material that contains 1 to 20 wt% zinc oxide added to indium oxide. Indium oxide containing tungsten oxide and zinc oxide is The target contains 0.5 to 5 wt% of tungsten oxide and 0.1 to 1 wt% of zinc oxide. By using a nozzle, it can be formed by sputtering. It may be prepared by a coating method, an ink jet method, a spin coating method, or the like.

[0101] In addition, in the EL layer 103 formed on the first electrode 102, the When a layer containing a composite material, which will be described later, is used as the material for the first layer 111 formed by In this case, the material used for the first electrode 102 may be any of various metals and alloys, regardless of the magnitude of the work function. Gold, electrically conductive compounds, and mixtures thereof can be used. Aluminum (Al), silver (Ag), and alloys containing aluminum (AlSi) can also be used. can.

[0102] In addition, materials with a small work function, such as elements belonging to Group 1 or 2 of the periodic table, That is, alkali metals such as lithium (Li) and cesium (Cs), magnesium (Mg) Alkaline earth metals such as calcium (Ca), strontium (Sr), and alloys containing these Rare earth elements such as gold (MgAg, AlLi), europium (Eu), and ytterbium (Yb) Metals and alloys containing these may also be used.

[0103] The first electrode is made of an alkali metal, an alkaline earth metal, or an alloy containing these metals. When forming the layer 102, a vacuum deposition method or a sputtering method can be used. In addition, when using silver paste, the coating method or inkjet method can be used. Cut.

[0104] The EL layer 103 formed on the first electrode 102 can be made of a known material. Both low molecular weight compounds and high molecular weight compounds can be used. The substances that form 3 include not only those that consist of organic compounds but also those that contain inorganic compounds. This also includes configurations that include:

[0105] The EL layer 103 is a hole injection layer containing a substance with high hole injection properties, a material with high hole transport properties, and a a hole transport layer comprising a material having high electron transport properties; a light emitting layer comprising a light emitting material; and an electron injection layer containing a material with high electron injection properties. It is formed by laminating.

[0106] The EL layer 103 shown in FIG. 1A is formed by a hole injection layer from the first electrode 102 side to the first layer (hole injection layer). layer) 111, a second layer (hole transport layer) 112, a third layer (light emitting layer) 113, a fourth layer (electrode A fifth layer (electron transport layer) 114 and a fifth layer (electron injection layer) 115 are laminated in this order.

[0107] The first layer 111, which is a hole-injecting layer, is a hole-injecting layer containing a substance with a high hole-injecting property. Materials with high hole injection properties include molybdenum oxide, titanium oxide, vanadium oxide, Rhenium oxide, ruthenium oxide, chromium oxide, zirconium oxide, hafnium oxide oxide, tantalum oxide, silver oxide, tungsten oxide, manganese oxide, etc. Other low molecular weight organic compounds include phthalocyanine (abbreviated as HPc), Copper (II) phthalocyanine (abbreviation: CuPc), vanadyl phthalocyanine (abbreviation: VOP In addition, the phthalocyanine compounds of the present invention shown in the first embodiment can be used. Fluorene derivatives, which are one embodiment, can also be used in the same manner.

[0108] In addition, the low molecular weight organic compound 4,4',4''-tris(N,N-diphenylamine) N-(3-)triphenylamine (abbreviation: TDATA), 4,4',4''-tris[N-(3- Methylphenyl)-N-phenylamino]triphenylamine (abbreviation: MTDATA), 4,4'-bis[N-(4-diphenylaminophenyl)-N-phenylamino]biphenyl Nyl (abbreviation: DPAB), 4,4'-bis(N-{4-[N'-(3-methylphenyl) -N'-phenylamino]phenyl}-N-phenylamino)biphenyl (abbreviation: DNT PD), 1,3,5-tris[N-(4-diphenylaminophenyl)-N-phenyla 3-[N-(9-phenylcarbazole-3-ylamino]benzene (abbreviation: DPA3B), [N-phenylamino]-9-phenylcarbazole (abbreviation: PCzPCA1), 3 ,6-bis[N-(9-phenylcarbazol-3-yl)-N-phenylamino]-9 -phenylcarbazole (abbreviation: PCzPCA2), 3-[N-(1-naphthyl)-N- (9-phenylcarbazol-3-yl)amino]-9-phenylcarbazole (abbreviation: Also included are aromatic amine compounds such as PCzPCN1). The fluorene derivative of one embodiment of the present invention can also be used in a similar manner.

[0109] Furthermore, polymeric compounds (oligomers, dendrimers, polymers, etc.) can also be used. For example, poly(N-vinylcarbazole) (abbreviation: PVK), poly(4-vinyltriazole) phenylamine) (abbreviation: PVTPA), poly[N-(4-{N'-[4-(4-diphenyl N-(Nylamino)phenyl]phenyl-N'-phenylamino}phenyl)methacrylamide ] (abbreviation: PTPDMA) poly[N,N'-bis(4-butylphenyl)- ... Examples include polymer compounds such as [poly(phenyl)benzidine] (abbreviation: Poly-TPD). In addition, poly(3,4-ethylenedioxythiophene) / poly(styrenesulfonic acid) (PEDOT / PSS), polyaniline / poly(styrene sulfonate) (PAni / PS It is also possible to use a polymer compound to which an acid such as methyl methyl stearate is added.

[0110] In addition, the first layer 111 may be formed by adding an acceptor substance to a substance having a high hole transporting property. A composite material having a high hole transporting property and an acceptor substance can be used. By using a material containing such a material, the material for forming the electrode can be selected regardless of the work function of the electrode. That is, the first electrode 102 can be made of a material having not only a large work function but also a material having a low work function. These composite materials can be used as materials with high hole transport properties. It can be formed by co-evaporating the acceptor material with the ion beam. In this context, composite does not simply mean mixing two materials, but mixing multiple materials. This means that materials can transfer electric charges between them.

[0111] The organic compounds used in the composite materials include aromatic amine compounds, carbazole derivatives, aromatic Aromatic hydrocarbons, polymer compounds (oligomers, dendrimers, polymers, etc.), and various chemical compounds As the organic compound used for the composite material, a hole transporting compound having It is preferable that the organic compound has a high molecular weight. -6 cm 2 / Vs or more However, it is preferable that the material has a higher hole transporting property than an electron transporting property. Other organic materials that can be used in the composite material are listed below. The compounds are specifically listed below.

[0112] Examples of organic compounds that can be used in composite materials include MTDATA and TDAT. A, DPAB, DNTPD, DPA3B, PCzPCA1, PCzPCA2, PCzPC N1,4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation N,N'-bis(3-methylphenyl)-N,N'-diphenyl Aromatic alkyl amines such as phenyl-[1,1'-biphenyl]-4,4'-diamine (abbreviation: TPD) amine compounds, 4,4'-di(N-carbazolyl)biphenyl (abbreviation: CBP), 1,3 ,5-tris[4-(N-carbazolyl)phenyl]benzene (abbreviation: TCPB), 9- [4-(N-carbazolyl)]phenyl-10-phenylanthracene (abbreviation: CzPA ), 1,4-bis[4-(N-carbazolyl)phenyl]-2,3,5,6-tetraphenyl Examples of the carbazole derivatives include carbazole derivatives such as phenylbenzene. The fluorene derivative which is one embodiment of the present invention can also be used for the composite material.

[0113] In addition, 2-tert-butyl-9,10-di(2-naphthyl)anthracene (abbreviation: t -BuDNA), 2-tert-butyl-9,10-di(1-naphthyl)anthracene, 9,10-bis(3,5-diphenylphenyl)anthracene (abbreviation: DPPA), 2- tert-Butyl-9,10-bis(4-phenylphenyl)anthracene (abbreviation: t- BuDBA), 9,10-di(2-naphthyl)anthracene (abbreviation: DNA), 9,10 -Diphenylanthracene (abbreviation: DPAnth), 2-tert-butylanthracene (abbreviation: t-BuAnth), 9,10-bis(4-methyl-1-naphthyl)anthracene DMNA, 9,10-bis[2-(1-naphthyl)phenyl]-2-tert-butyl ether t-Butyl-anthracene, 9,10-bis[2-(1-naphthyl)phenyl]anthracene 2,3,6,7-tetramethyl-9,10-di(1-naphthyl)anthracene, etc. Aromatic hydrocarbon compounds can be mentioned.

[0114] Furthermore, 2,3,6,7-tetramethyl-9,10-di(2-naphthyl)anthracene , 9,9'-bianthryl, 10,10'-diphenyl-9,9'-bianthryl, 10 ,10'-bis(2-phenylphenyl)-9,9'-bianthryl, 10,10'-bi bis[(2,3,4,5,6-pentaphenyl)phenyl]-9,9'-bianthryl, tetracene, rubrene, perylene, 2,5,8,11-tetra(tert- butyl)perylene, pentacene, coronene, 4,4'-bis(2,2-diphenylvinyl ) biphenyl (abbreviation: DPVBi), 9,10-bis[4-(2,2-diphenylvinyl )phenyl]anthracene (abbreviation: DPVPA) and other aromatic hydrocarbon compounds. can be done.

[0115] As an acceptor substance, 7,7,8,8-tetracyano-2,3,5,6 -Tetrafluoroquinodimethane (abbreviation: F4-TCNQ), chloranil and other organic compounds In addition, oxides of transition metals in Groups 4 to 8 of the periodic table can be used. Examples of oxides of metals belonging to the group include vanadium oxide, niobium oxide, Tantalum oxide, chromium oxide, molybdenum oxide, tungsten oxide, manganese oxide, lenium oxide Molybdenum oxide is particularly stable in the atmosphere. It is preferable because it has low hygroscopicity and is easy to handle.

[0116] In addition, the polymer compounds such as PVK, PVTPA, PTPDMA, and Poly-TPD mentioned above A composite material is formed using the above-mentioned acceptor material and used for the first layer 111. Note that the fluorene derivative which is one embodiment of the present invention described in Embodiment 1 may also be A composite material can be formed by combining with an acceptor substance and used for the first layer 111. Cut.

[0117] The second layer 112, which is a hole transport layer, is a layer containing a substance with a high hole transport property. The second layer 112 in this embodiment is made of the material described in the first embodiment of the present invention. The fluorene derivative according to one embodiment of the present invention is Because of its wide band gap, the second layer 112 formed from this fluorene derivative is The exciton energy generated in the adjacent third layer 113 (light-emitting layer) is hardly absorbed, and the excitons are This allows efficient confinement in the light-emitting layer, resulting in a highly efficient light-emitting device.

[0118] In addition, both the first layer 111 and the second layer 112 are provided with one of the materials according to the present invention described in the first embodiment. In this case, the device can be easily fabricated. In addition, the efficiency of material utilization can be improved. Since the energy diagrams of the first layer 111 and the second layer 112 are the same or close to each other, This allows for easy movement of carriers between the electrodes.

[0119] The third layer 113 is a light-emitting layer containing a highly light-emitting substance. The low molecular weight organic compounds listed below can be used. The fluorene derivative, which is one embodiment, also exhibits light-emitting properties and can be used as a light-emitting material.

[0120] Examples of the luminescent substance include a fluorescent compound that emits fluorescence and a phosphorescent compound that emits phosphorescence. can be used.

[0121] Examples of fluorescent materials that can be used in the light-emitting layer 113 include blue-based light-emitting materials. As N,N'-bis[4-(9H-carbazol-9-yl)phenyl]-N,N' -Diphenylstilbene-4,4'-diamine (abbreviation: YGA2S), 4-(9H-calcium (bazol-9-yl)-4'-(10-phenyl-9-anthryl)triphenylamine (Abbreviation: YGAPA) and others.

[0122] Green luminescent materials include N-(9,10-diphenyl-2-anthryl)-N,9 -diphenyl-9H-carbazol-3-amine (abbreviation: 2PCAPA), N-[9,1 0-Bis(1,1'-biphenyl-2-yl)-2-anthryl]-N,9-diphenyl -9H-carbazol-3-amine (abbreviation: 2PCABPhA), N-(9,10-difluoromethyl) (phenyl-2-anthryl)-N,N',N'-triphenyl-1,4-phenylenediamine N-[9,10-bis(1,1'-biphenyl-2-yl)] (abbreviation: 2DPAPA) -2-anthryl]-N,N',N'-triphenyl-1,4-phenylenediamine (abbreviation Name: 2DPABPhA), 9,10-bis(1,1'-biphenyl-2-yl)-N-[ 4-(9H-carbazol-9-yl)phenyl]-N-phenylanthracene-2-a amine (abbreviation: 2YGABPhA), N,N,9-triphenylanthracene-9-amine (abbreviation: DPhAPhA) and others.

[0123] Yellow luminescent materials include rubrene, 5,12-bis(1,1'-biphenyl-4- (yl)-6,11-diphenyltetracene (abbreviation: BPT), etc. As a red luminescent material, N,N,N',N'-tetrakis(4-methylphenyl)tetrakis Helical-5,11-diamine (abbreviation: p-mPhTD), 7,14-diphenyl-N,N ,N',N'-Tetrakis(4-methylphenyl)acenaphtho[1,2-a]fluoran Examples include phen-3,10-diamine (abbreviation: p-mPhAFD).

[0124] Furthermore, examples of phosphorescent compounds that can be used in the light-emitting layer 113 include blue-based phosphorescent compounds. 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 (I II) Picolinate (abbreviation: FIrpic), bis{2-[3',5'-bis(trifluoromethyl)methyl] (Oromethyl)phenyl]pyridinato-N,C 2’}Iridium(III) picolinate( Abbreviation: Ir(CF3ppy)2(pic)), bis[2-(4',6'-difluorophenyl) Nyl)pyridinato-N,C 2’ ]Iridium(III) acetylacetonate (abbreviation: F Ir(acac)) and the like. In addition, tris(2-fluorophenyl) Phenylpyridinato-N,C 2’ ) Iridium(III) (abbreviation: Ir(ppy)3), Su(2-phenylpyridinato-N,C 2’ ) Iridium(III) acetylacetonate (abbreviation: Ir(ppy)2(acac)), bis(1,2-diphenyl-1H-benzoyl) Midazolato)iridium(III) acetylacetonate (abbreviation: Ir(pbi)2(a cac)), bis(benzo[h]quinolinato)iridium(III) acetylacetoner (abbreviation: Ir(bzq)2(acac)). Bis(2,4-diphenyl-1,3-oxazolato-N,C 2’ )iridium( III) Acetylacetonate (abbreviation: Ir(dpo)2(acac)), bis[2-( 4'-perfluorophenylphenyl)pyridinato]iridium(III) acetylacetone Tonanate (abbreviation: Ir(p-PF-ph)2(acac)), bis(2-phenylbenzo[a] Thiazolato-N,C 2’ ) Iridium(III) acetylacetonate (abbreviation: Ir(b In addition, orange light-emitting materials include tris(2- Phenylquinolinato-N,C 2’) Iridium(III) (abbreviation: Ir(pq)3), Bi Su(2-phenylquinolinato-N,C 2’ ) Iridium(III) acetylacetonate (abbreviation: Ir(pq)2(acac)) and the like. Bis[2-(2'-benzo[4,5-α]thienyl)pyridinato-N,C 3’ ]Ili Ir(btp)2(acac) (1-phenylisoquinolinato-N,C 2’ ) Iridium(III) acetylacetoner Ir(piq)2(acac) (acetylacetonato)bis[2,3-bis(acetylacetonato)bis( ... [Fd(4-fluorophenyl)quinoxalinato]iridium(III) (abbreviation: Ir(Fd pq)2(acac)), 2,3,7,8,12,13,17,18-octaethyl-2 Examples include organometallic complexes such as 1H,23H-porphyrin platinum(II) (abbreviation: PtOEP). Also, tris(acetylacetonato)(monophenanthroline)terbium(I II) (abbreviation: Tb(acac)3(Phen)), tris(1,3-diphenyl-1, 3-propanedionato)(monophenanthroline)europium(III)(abbreviation:Eu (DBM)3(Phen)), tris[1-(2-thenoyl)-3,3,3-trifluoromethyl [TTA](monophenanthroline)europium(III) (abbreviation: Eu(TTA) Rare earth metal complexes such as 3(Phen) exhibit luminescence from rare earth metal ions (different multiplicities) Since it is an electron transition between two atoms, it can be used as a phosphorescent compound.

[0125] The third layer 113 has a structure in which the above-described highly light-emitting substance is dispersed in another substance. In the case of dispersion, the concentration of the substance (dopant) to be dispersed may be in the range of 1000 to 10000 by mass ratio. It is preferable that the amount of the luminous material be 20% or less of the total amount. As the host, a known substance can be used, but a light-emitting substance (dopant) ) has a shallower (smaller absolute value) lowest unoccupied molecular orbital level (LUMO level) than the highest occupied molecular orbital level It is preferable to use a substance with a deep HOMO level (large absolute value). The band gap (Bg: the difference between the HOMO level and the LUMO level) of the luminescent dopant B g. When the dopant emits light with fluorescence, the S1 level is preferably higher than the phosphorus level. In the case of photoactivity, it is preferable that the T1 level of the host is higher than that of the dopant.

[0126] Specifically, tris(8-quinolinolato)aluminum(III) (abbreviation: Alq), Tris(4-methyl-8-quinolinolato)aluminum(III) (Almq3) , bis(10-hydroxybenzo[h]quinolinato)beryllium(II) (abbreviation: BeB q2), bis(2-methyl-8-quinolinolato)(4-phenylphenolato)aluminum zinc(III) (abbreviation: BAlq), bis(8-quinolinolato)zinc(II) (abbreviation: Zn q), bis[2-(2-benzoxazolyl)phenolato]zinc(II) (abbreviation: ZnP BO), bis[2-(2-benzothiazolyl)phenolato]zinc(II) (abbreviation: ZnB Metal complexes such as TZ can be used.

[0127] Also, 2-(biphenyl-4-yl)-5-(4-tert-butylphenyl)-1, 3,4-Oxadiazole (abbreviation: PBD), 1,3-bis[5-(p-tert-butyl) phenyl)-1,3,4-oxadiazol-2-yl]benzene (abbreviation: OXD-7 ), 3-(biphenyl-4-yl)-4-phenyl-5-(4-tert-butylphenyl) 2,2',2''-(1,3,5-triazole)-1,2,4-triazole (abbreviation: TAZ), Benzenetriyl)tris(1-phenyl-1H-benzimidazole) (abbreviation: TPB I), bathophenanthroline (abbreviated as BPhen), bathocuproine (abbreviated as BCP) Heterocyclic compounds such as the following can be used.

[0128] Others include 9-[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazo CzPA, 3,6-diphenyl-9-[4-(10-phenyl-9-anthracene] tolyl)phenyl]-9H-carbazole (abbreviation: DPCzPA), 9,10-bis(3 ,5-diphenylphenyl)anthracene (abbreviation: DPPA), 9,10-di(2-naphthyl)anthracene 2-tert-butyl-9,10-di(2-naphthyl)anthracene (abbreviation: DNA), t-BuDNA), 9,9'-Bianthryl (BAN T), 9,9'-(stilbene-3,3'-diyl)diphenanthrene (abbreviation: DPNS ), 9,9'-(stilbene-4,4'-diyl)diphenanthrene (abbreviation: DPNS2 ), 3,3',3''-(benzene-1,3,5-triyl)tripylene (abbreviation: TPB Condensed aromatic compounds such as 3) can also be used.

[0129] In addition, a plurality of materials can be used to disperse the light-emitting material. In order to suppress crystallization, a substance that suppresses crystallization, such as rubrene, may be further added. In order to transfer energy to the luminescent material more efficiently, NPB or Alq Note that the fluorene derivative which is one embodiment of the present invention described in Embodiment 1 may be added. In this way, a structure in which a highly luminescent substance is dispersed in another substance can be used. This can suppress the crystallization of the third layer 113. Concentration quenching due to high concentrations of substances can be suppressed.

[0130] In addition, among the above-mentioned substances, a light-emitting substance is dispersed using a substance with electron transport properties. It is more preferable to form the third layer 113. Specifically, the above-mentioned metal complexes, heterocycles, etc. compounds, condensed aromatic compounds CzPA, DNA, t-BuDNA, and later The polymer compound shown in the table below can be used for the fourth layer 114. It is also possible.

[0131] The third layer 113 may also be made of the following polymer compounds.

[0132] Poly(9,9-dioctylfluorene-2,7-diyl) is a blue-emitting material. (abbreviation: PFO), poly[(9,9-dioctylfluorene-2,7-diyl)-co- (2,5-dimethoxybenzene-1,4-diyl)] (abbreviation: PF-DMOP), poly{ (9,9-dioctylfluorene-2,7-diyl)-co-[N,N'-di-(p-butyl) (Tetrphenyl)-1,4-diaminobenzene] (abbreviation: TAB-PFH) can be.

[0133] Green light-emitting materials include poly(p-phenylene vinylene) (abbreviated as PPV), poly [(9,9-dihexylfluorene-2,7-diyl)-alt-co-(benzo[2, 1,3]thiadiazole-4,7-diyl)] (abbreviation: PFBT), poly[(9,9-di Octyl-2,7-divinylenefluorenylene)-alt-co-(2-methoxy-5- (2-ethylhexyloxy)-1,4-phenylene)].

[0134] Orange to red luminescent materials include poly[2-methoxy-5-(2'-ethylhexyl) (II)-1,4-phenylene vinylene] (abbreviation: MEH-PPV), poly(3-butylthio) phen-2,5-diyl) (abbreviation: R4-PAT), poly{[9,9-dihexyl-2, 7-bis(1-cyanovinylene)fluorenylene]-alt-co-[2,5-bis(N ,N'-diphenylamino)-1,4-phenylene]}, poly{[2-methoxy-5-( 2-ethylhexyloxy)-1,4-bis(1-cyanovinylenephenylene)]-alt -co-[2,5-bis(N,N'-diphenylamino)-1,4-phenylene]}(abbreviation Examples include CN-PPV-DPD.

[0135] The light-emitting layer 113 may be formed of two or more layers. When the light-emitting layer 113 is formed by laminating the first light-emitting layer and the second light-emitting layer in this order from the hole transport layer side, A substance having hole transporting properties is used as a host material for the first light-emitting layer, and a substance having hole transporting properties is used as a host material for the second light-emitting layer. A substance having an electron transporting property can be used. More preferably, the host material of the first light-emitting layer The host material of the second emitting layer is a material with higher hole transporting property than electron transporting property. A material having a high electron transporting property is preferred over a material having a high electron transporting property. The space between the two light-emitting layers becomes the light-emitting site, resulting in a more efficient device.

[0136] When the light-emitting layer having the above structure is made up of multiple materials, it can be formed by vacuum deposition. Co-deposition or mixed solution of It can be prepared by the method such as the PET method.

[0137] The fourth layer 114 is an electron transport layer containing a substance with a high electron transport property. For example, low molecular weight organic compounds include Alq, Almq3, BeBq2, BAlq, Metal complexes such as Znq, ZnPBO, and ZnBTZ can be used. In addition to the benzodiazepines, heterocyclic compounds such as PBD, OXD-7, TAZ, TPBI, BPhen, and BCP are also The substances mentioned here are mainly 10 -6 cm 2 / Vs or more It should be noted that if a substance has a higher electron transporting property than a hole transporting property, The electron transport layer may be formed of a single layer or a multilayer structure. Alternatively, two or more layers made of the above materials may be laminated.

[0138] A polymer compound can also be used for the fourth layer 114. For example, poly[(9,9- dihexylfluorene-2,7-diyl)-co-(pyridine-3,5-diyl)](abbreviation Name: PF-Py), poly[(9,9-dioctylfluorene-2,7-diyl)-co- (2,2'-bipyridine-6,6'-diyl)] (abbreviation: PF-BPy) This can be done.

[0139] The fifth layer 115 is an electron injection layer containing a substance with high electron injection properties. 15 includes lithium fluoride (LiF), cesium fluoride (CsF), calcium fluoride ( Use alkali metals, alkaline earth metals, or their compounds such as CaF2 In addition, the substance having an electron transport property may be an alkali metal, an alkaline earth metal, or or compounds thereof, specifically magnesium (Mg) in Alq In this case, electron injection from the second electrode 104 may be performed. can be done more efficiently.

[0140] The second electrode 104 is made of a metal, alloy, or The cathode material may be an electrically conductive compound or a mixture thereof. A specific example of this is an element belonging to group 1 or 2 of the periodic table, namely lithium ( Alkali metals such as Li and cesium (Cs), as well as magnesium (Mg) and calcium Alkaline earth metals such as (Ca), strontium (Sr), and alloys containing these (M Rare earth metals such as Ag, Al, Li, europium (Eu), ytterbium (Yb) and and alloys containing these.

[0141] The second electrode 104 may be made of an alkali metal, an alkaline earth metal, or an alloy containing these metals. When forming the silver foil, a vacuum deposition method or a sputtering method can be used. When paste or the like is used, a coating method, an ink jet method, or the like can be used.

[0142] By providing the fifth layer 115, it is possible to use Al, Ag, Various conductive materials such as ITO, indium tin oxide containing silicon or silicon oxide The second electrode 104 can be formed using these conductive materials. The film can be formed by a coating method, an ink jet method, a spin coating method, or the like.

[0143] The first layer (hole injection layer) 111, the second layer (hole transport layer) 112, the third layer (light emitting layer) a fourth layer (electron transport layer) 114, and a fifth layer (electron injection layer) 115 are arranged in this order. The EL layer 103 formed by subsequent lamination can be produced by various methods, whether dry or wet. For example, a vacuum deposition method, an ink jet method, or a spin coating method can be used. It is also possible to use a different film formation method for each layer. .

[0144] The second electrode 104 can be formed by not only a dry method such as a sputtering method or a vacuum deposition method, but also a The metal layer can be formed by a wet method such as a sol-gel method using a paste of a metal material.

[0145] The first electrode 102, the first layer (hole injection layer) 111, and the second layer (hole transport layer) Since holes mainly flow between the second layer (light-emitting layer) 112 and the third layer (light-emitting layer) 113, the carrier between the adjacent layers is In order to reduce the injection barrier, the HOMO level (work function in the case of metals) is the same or similar. Similarly, the third layer (light-emitting layer) 113 and the fourth layer (electron transport layer) The gap between the second electrode 104 and the fifth layer (electron injection layer) 114, the fifth layer (electron injection layer) 115, and the second electrode 104 is mainly for passing electrons. Therefore, the LUMO level (or the limit level in the case of metals) is adjusted to reduce the carrier injection barrier between adjacent layers. It is desirable that the difference between the two is within 0.2 eV, and more preferably, More preferably, it is within 0.1 eV.

[0146] In addition, the second layer (hole transport layer) 112 and the third layer (light emitting layer) 113 are intentionally HOMO level, LUMO between the third layer (light-emitting layer) 113 and the fourth layer (electron transport layer) 114 By increasing the difference in levels, carriers can be confined in the light-emitting layer, resulting in a more efficient light-emitting element. However, in this case, if the barrier is too large, the driving voltage will increase, which will cause a burden on the device. Therefore, the difference is preferably within 0.4 eV, more preferably within 0.2 eV. It is preferable that

[0147] The light-emitting element according to one embodiment of the present invention has a first electrode 102 and a second electrode 104. The potential difference between them causes a current to flow, and holes and electrons are recombined in the EL layer 103. This light emission occurs when either the first electrode 102 or the second electrode 104 Therefore, the electric current is taken out through either the first electrode 102 or the second electrode 103. Either one or both of the two electrodes 104 is a light-transmitting electrode.

[0148] In addition, when only the first electrode 102 is a light-transmitting electrode, In this way, light emitted from the EL layer 103 passes through the first electrode 102 and is extracted from the substrate 101 side. In addition, when only the second electrode 104 is a light-transmitting electrode, As shown in FIG. 1, light emitted from the EL layer 103 is emitted to the opposite side of the substrate 101 through the second electrode 104. Furthermore, both the first electrode 102 and the second electrode 104 are transparent. In the case of an electrode having the same structure, as shown in FIG. 2(C), light emitted from the EL layer 103 is through the first electrode 102 and the second electrode 104, are taken from both.

[0149] The structure of the layers provided between the first electrode 102 and the second electrode 104 is the same as that described above. The second layer 112 is a hole transport layer, and the light emitting layer is a light emitting layer. As long as it has a configuration including the third layer 113, other configurations than those described above may also be used.

[0150] As shown in FIG. 1B, a second electrode 104 functioning as a cathode is formed on the substrate 101. The first electrode 102 may be formed by laminating an EL layer 103 and a first electrode 102 that functions as an anode in this order. In this case, the EL layer 103 is formed by forming a fifth layer 115 on the second electrode 104 and a fourth layer 114, the third layer 113, the second layer 112, the first layer 111, and the first electrode 102 are stacked in this order. It has a layered structure.

[0151] By using the light-emitting element of the present invention, a passive matrix light-emitting device or a thin film transistor Active matrix light emitting device in which the driving of light emitting elements is controlled by thin film transistors (TFTs) Optical devices can be fabricated.

[0152] In the case of manufacturing an active matrix type light emitting device, the structure of the TFT is For example, a staggered or inverted staggered TFT may be used as appropriate. In addition, the driving circuit formed on the TFT substrate is also made up of N-type and P-type TFTs. Alternatively, the TFT may be composed of only one of N-type TFTs or P-type TFTs. Furthermore, there is no particular limitation on the crystallinity of the semiconductor film used in the TFT. An amorphous semiconductor film or a crystalline semiconductor film may be used.

[0153] In the light-emitting element described in this embodiment, the second layer (hole-transporting layer) 112 is a Since the device is formed using a fluorene derivative, which is similar to , power consumption can be minimized.

[0154] (Embodiment 3) In this embodiment, a light-emitting element ( The embodiment of the light-emitting element (hereinafter referred to as a stacked element) will be described with reference to FIG. The light emitting device is a stacked type light emitting device having a plurality of light emitting units between a first electrode and a second electrode. The configuration of each light-emitting unit may be the same as that shown in the second embodiment. That is, the light-emitting element described in Embodiment 2 is a light-emitting element having one light-emitting unit. In this embodiment mode, a light-emitting element having a plurality of light-emitting units will be described.

[0155] In FIG. 3A, a first light-emitting unit is disposed between a first electrode 521 and a second electrode 522. The first electrode 521 and the second light-emitting unit 512 are stacked. The electrode 522 can be the same as that in the second embodiment. The first light-emitting unit 511 and the second light-emitting unit 512 may have the same configuration or different configurations. The configuration can be the same as that of the second embodiment.

[0156] When a voltage is applied between the first electrode 521 and the second electrode 522, the charge generating layer 513 generates a A layer that injects electrons into the light-emitting unit on one side and holes into the light-emitting unit on the other side. The structure may be a single layer or a laminate of multiple layers. The layer preferably has a structure in which a layer for injecting holes and a layer for injecting electrons are stacked.

[0157] The hole injection layer is made of molybdenum oxide, vanadium oxide, rhenium oxide, or rhenium oxide. A semiconductor or insulator such as ruthenium can be used. Alternatively, a material with high hole transport properties can be used. Alternatively, an acceptor substance may be added to the hole transport layer. The layer containing the acceptor material contains 7,7,8,8-tetracyano-2, 3,5,6-tetrafluoroquinodimethane (abbreviation: F4-TCNQ) and vanadium oxide Metal oxides such as molybdenum oxide and tungsten oxide are included as materials with high hole transport properties. Examples include aromatic amine compounds, carbazole derivatives, aromatic hydrocarbons, polymer compounds, and oligomers. Various compounds such as copolymers, dendrimers, and polymers can be used. The fluorene derivative according to one embodiment of the present invention shown in Form 1 can also be used in the same manner. As a material with a high hole transporting property, a material with a hole mobility of 10 -6 cm 2 / Vs or more However, if a material has a higher hole transporting property than an electron transporting property, this may be used. A composite material containing a substance with high hole transporting properties and a substance with acceptor properties may also be used. The material has excellent carrier injection and carrier transport properties, allowing for low voltage and low current operation. It can be realized.

[0158] The electron injection layer is made of an insulator such as lithium oxide, lithium fluoride, or cesium carbonate. Alternatively, a donor substance can be added to a substance with high electron transport properties. The donor substance may be an alkali metal or alkaline earth metal. Metals, rare earth metals, or metals belonging to Group 13 of the Periodic Table and their oxides Specifically, lithium (Li), cesium (Cs), magnesium (Mg), and carbonates can be used. Magnesium (Mg), calcium (Ca), ytterbium (Yb), indium (In ), lithium oxide, cesium carbonate, etc. are preferably used. An organic compound such as benzene may be used as the donor substance. For the electron-transporting layer, the materials described in Embodiment 1 can be used. The electron mobility is 10 -6 cm 2 It is preferable to apply a value of 0.1 V or more. However, other substances may be used as long as they have a higher electron transporting property than a hole transporting property. A composite material having a substance with high electron transport properties and a donor substance has carrier injection properties, Because of its excellent transport properties, it can be driven at low voltage and low current.

[0159] In addition, the electrode material shown in Embodiment Mode 2 can also be used for the charge generation layer 513. For example, a layer containing a material with high hole transport properties, a metal oxide, and a transparent conductive film can be combined. From the viewpoint of light extraction efficiency, the charge generation layer 513 is preferably a highly light-transmitting layer. It is preferable that

[0160] In any case, the electrode sandwiched between the first light-emitting unit 511 and the second light-emitting unit 512 When a voltage is applied to the first electrode 521 and the second electrode 522, the charge generation layer 513 generates a Electrons are injected into the light-emitting unit on one side, and holes are injected into the light-emitting unit on the other side. For example, the voltage is set so that the potential of the first electrode is higher than the potential of the second electrode. When a voltage is applied, the charge generating layer 513 injects electrons into the first light-emitting unit 511 and Any configuration may be used as long as it can inject holes into the light-emitting unit 512.

[0161] In this embodiment, a light emitting element having two light emitting units has been described. As shown in FIG. 3(B), the same can be said for a light-emitting element in which three or more light-emitting units are stacked. As in the light-emitting element according to the present embodiment, the light-emitting element can be applied in various ways. By separating and arranging a plurality of light-emitting units with the charge generating layer 513, the current density can be kept low. In addition, when applied to lighting, it is possible to realize a long-life element in the high brightness range. The voltage drop due to the resistance of the electrode material can be reduced, making it possible to emit light uniformly over a large area. Furthermore, a light emitting device that can be driven at a low voltage and consumes low power can be realized.

[0162] In addition, by making the light-emitting color of each light-emitting unit different, the light-emitting element as a whole For example, a light-emitting element having two light-emitting units can be used. In this case, the luminous color of the first luminous unit and the luminous color of the second luminous unit are in a complementary color relationship. By doing so, it is possible to obtain a light emitting element that emits white light as a whole. In addition, complementary colors are colors that become achromatic when mixed. By mixing light from materials that emit light of certain colors, white light can be obtained. The same applies to a light-emitting element having three light-emitting units. For example, the first light-emitting unit The light emitting color of the first light emitting unit is red, the light emitting color of the second light emitting unit is green, and the light emitting color of the third light emitting unit is red. When the emitted light color of the dot is blue, the light emitting element as a whole can emit white light.

[0163] Note that this embodiment mode can be combined with other embodiment modes as appropriate.

[0164] (Fourth embodiment) In this embodiment mode, a light-emitting device having a light-emitting element of the present invention in a pixel portion will be described with reference to FIG. 4A is a top view showing a light-emitting device, and FIG. 4B is a cross-sectional view of FIG. 4A. Cross-sectional views taken along lines A' and B-B'.

[0165] In FIG. 4A, 401 indicated by a dotted line is a driving circuit section (source side driving circuit), 40 2 is a pixel section, 403 is a driving circuit section (gate side driving circuit), and 404 is a sealing substrate. , 405 is a sealing material, and the inside surrounded by the sealing material 405 is a space 407. .

[0166] The lead wiring 408 is connected to the source side driver circuit 401 and the gate side driver circuit 403. The wiring is for transmitting the input signal, and the FPC (flexible printed circuit board) is the external input terminal. Video signal, clock signal, start signal, reset signal from Lint Circuit 409 Although only the FPC is shown here, this FPC has a printed circuit board. A printed wiring board (PWB) may be attached. This includes not only the light-emitting device itself, but also the state in which an FPC or PWB is attached to it. It shall be.

[0167] Next, the cross-sectional structure will be described with reference to FIG. A source side driver circuit 401, which is a driver circuit section, is formed in this example. 4 shows one pixel in the pixel section 402. The source side driver circuit 401 is an N-channel A CMOS circuit is formed by combining a P-channel TFT423 and a P-channel TFT424. The driving circuit can be a variety of CMOS circuits, PMOS circuits, or NMOS circuits. In this embodiment, a driver integrated type in which a driver circuit is formed on a substrate is shown. However, this is not necessarily required, and the drive circuit can be formed externally rather than on the substrate.

[0168] The pixel section 402 includes a switching TFT 411, a current control TFT 412, and The pixel is formed by a plurality of pixels including a first electrode 413 electrically connected to the drain. An insulator 414 is formed to cover the edge of the first electrode 413 .

[0169] In order to improve the covering property, the upper end or the lower end of the insulator 414 is provided with a curvature. For example, the material of the insulator 414 is a positive electrode. By using a photosensitive acrylic mold, the radius of curvature (0.2 μm) was set only at the top end of the insulator 414. In addition, the insulating material 414 can be used to provide a curved surface having a thickness of about 3 μm. Negative type that becomes insoluble in etchant by irradiation with light, or Any positive photosensitive material that is soluble can be used.

[0170] An EL layer 416 and a second electrode 417 are formed on the first electrode 413. Here, the material used for the first electrode 413 may be various metals, alloys, electrically conductive materials, The following compounds and mixtures thereof can be used: The materials shown in the second embodiment as usable for the first electrode can be used. It shall be possible.

[0171] The EL layer 416 can be formed by a deposition method using a deposition mask, an inkjet method, or a spin coating method. The EL layer 416 has the structure shown in Embodiment 2. Other materials constituting the EL layer 416 include low molecular weight compounds or high molecular weight compounds. The material used for the EL layer may be a polymer compound (including an oligomer and a dendrimer). As the material, not only organic compounds but also inorganic compounds may be used.

[0172] The second electrode 417 may be made of various metals, alloys, or electrically conductive materials. The second electrode 417 is used as a cathode. In this case, metals, alloys, and electrodes with small work functions (work functions of 3.8 eV or less) are used. It is preferable to use a conductive compound and a mixture thereof. Elements belonging to Group 1 or 2 of the table, such as lithium (Li) and cesium (Cs) Alkali metals, as well as magnesium (Mg), calcium (Ca), strontium ( Examples include alkaline earth metals such as Sr, and alloys containing these metals (MgAg, AlLi). can be done.

[0173] In addition, in the case where the light generated in the EL layer 416 is transmitted through the second electrode 417, The electrode 417 of the second electrode is a thin metal film and a transparent conductive film (indium oxide-oxide). Tin oxide (ITO), indium oxide containing silicon or silicon oxide, indium tin oxide, Indium-zinc oxide (IZO), indium oxide containing tungsten oxide and zinc oxide It is also possible to use a laminate with a material such as a polyimide.

[0174] Furthermore, by bonding the sealing substrate 404 to the element substrate 410 with the sealing material 405, The light is emitted into a space 407 surrounded by the element substrate 410, the sealing substrate 404, and the sealant 405. The structure is provided with an element 418. The space 407 is filled with a filler. In addition to being filled with an inert gas (nitrogen, argon, etc.), it is also possible to fill it with a sealing material 405. In some cases, this may be the case.

[0175] It is preferable to use an epoxy resin for the sealing material 405. It is desirable that the sealing substrate 404 be made of a material that is as impermeable to moisture and oxygen as possible. Materials used for this include glass substrates, quartz substrates, and FRP (Fiberglass-Reinforced Plastics). Enforced Plastics), PVF (Polyvinyl Fluoride), Polyester Alternatively, a plastic substrate made of acrylic or the like can be used.

[0176] In this manner, an active matrix light emitting device having the light emitting element of the present invention is obtained. It is possible.

[0177] The light-emitting element of the present invention can be used not only in the above-mentioned active matrix light-emitting device but also in a panel light-emitting device. The light-emitting element of the present invention can also be used in a passive matrix light-emitting device. 5A and 5B show a perspective view and a cross-sectional view of a passive matrix light-emitting device. 5(B) is a cross-sectional view of FIG. 5(A) taken along the XY line.

[0178] In FIG. 5, an EL layer is disposed between a first electrode 502 and a second electrode 503 on a substrate 501. The end of the first electrode 502 is covered with an insulating layer 505. A partition layer 506 is provided on the insulating layer 505. The sidewalls of the partition layer 506 are in contact with the substrate surface. As the distance between the side walls approaches , the distance between the side walls becomes narrower. That is, the cross section of the partition layer 506 in the short side direction is trapezoidal, and the bottom side (the surface direction of the insulating layer 505) The side that faces the same direction as the insulating layer 505) faces the upper side (the side that faces the same direction as the insulating layer 505). The side of the partition wall layer 506 is oriented in the same direction as the insulating layer 505 and is shorter than the side of the partition wall layer 506 that is not in contact with the insulating layer 505. By providing the protective film, defects in the light-emitting element due to static electricity or the like can be prevented.

[0179] As a result, a passive matrix light emitting device having the light emitting element of the present invention can be obtained. can.

[0180] Note that the light-emitting device (active matrix type, passive matrix type) shown in this embodiment mode Since both of the above types are formed using the light-emitting element of the present invention with high luminous efficiency, the power consumption is low. A light emitting device with reduced forces can be obtained.

[0181] In the fourth embodiment, the configurations shown in the first to third embodiments are appropriately combined. It may be used.

[0182] (Embodiment 5) In this embodiment mode, an electronic device including the light-emitting device of the present invention shown in Embodiment Mode 4 as a part thereof will be described. The electronic devices include cameras such as video cameras and digital cameras, goggles, etc. display, navigation system, sound reproduction equipment (car audio, audio Ocompo, etc.), computers, game devices, personal digital assistants (mobile computers, mobile telephones, portable game consoles, electronic books, etc.), image playback devices equipped with recording media (specifically, , Digital Versatile Disc (DVD) and other recording media, (Devices equipped with a display device capable of displaying images of the above) An example is shown in Figure 6.

[0183] FIG. 6A illustrates a television device according to one embodiment of the present invention, which includes a housing 611, a support base 612, a display panel, and a display panel. This television device includes a display unit 613, a speaker unit 614, a video input terminal 615, etc. In this case, the light-emitting device of the present invention can be applied to the display portion 613. Since the light emitting device of the present invention has the feature of being able to obtain high light emitting efficiency, This makes it possible to obtain a television device with reduced power consumption.

[0184] FIG. 6B shows a computer according to one embodiment of the present invention, which includes a main body 621, a housing 622, a display display unit 623, keyboard 624, external connection port 625, pointing device 626 In this computer, the light emitting device of the present invention is applied to the display unit 623. The light emitting device of the present invention is characterized in that it can obtain high light emitting efficiency. Therefore, by applying the light emitting device of the present invention, a computer with reduced power consumption can be obtained. This can be done.

[0185] FIG. 6C shows a mobile phone according to one embodiment of the present invention, which includes a main body 631, a housing 632, a display unit 633, an audio input unit 634, an audio output unit 635, operation keys 636, and an external connection port 637 In this mobile phone, the display unit 633 includes a light emitting device according to the present invention. The light emitting device of the present invention has the feature of being able to obtain high light emitting efficiency. Therefore, by applying the light emitting device of the present invention, a mobile phone with reduced power consumption can be obtained. can be obtained.

[0186] FIG. 6D shows a camera according to one embodiment of the present invention, which includes a main body 641, a display unit 642, and a housing 6 43, external connection port 644, remote control receiver 645, image receiver 646, battery 647 , a voice input unit 648, operation keys 649, an eyepiece unit 650, etc. The light emitting device of the present invention can be applied to the display unit 642. Since the light emitting device of the present invention has the characteristic of being able to obtain high luminous efficiency, This makes it possible to obtain a camera with reduced power consumption.

[0187] As described above, the light emitting device of the present invention has a very wide range of applications, and can be used in a variety of fields. By using the light emitting device of the present invention, it is possible to reduce power consumption. Reduced force electronics can be obtained.

[0188] The light emitting device of the present invention can also be used as a lighting device. This is an example of a liquid crystal display device using a light source as a backlight. The device has a housing 701, a liquid crystal layer 702, a backlight 703, and a housing 704. 2 is connected to a driver IC 705. The backlight 703 is a light emitting device according to the present invention. An optical device is used and electrical current is supplied by terminal 706 .

[0189] In this way, by using the light emitting device of the present invention as a backlight for a liquid crystal display device, A backlight with low power consumption can be obtained. In addition, the light emitting device of the present invention is a surface-emitting lighting device. Since the area can be increased, the backlight area can also be increased. It is possible to obtain a liquid crystal display device with a large area.

[0190] FIG. 8 shows an example in which a light emitting device to which the present invention is applied is used as a desk lamp, which is a lighting device. The desk lamp shown in FIG. 8 has a housing 801 and a light source 802. The light emitting device of the present invention is used in the above-described light emitting device. Therefore, it can be used as a low-power desk lamp.

[0191] FIG. 9 shows an example in which a light emitting device to which the present invention is applied is used as an indoor lighting device 901. The light emitting device of the present invention can be made large in area, and therefore can be used as a large-area lighting device. In addition, the light emitting device of the present invention has a light emitting element with high light emitting efficiency, and therefore consumes low power. In this way, the light emitting device to which the present invention is applied can be used as a lighting device with a high power. In the room used as the indoor lighting device 901, the lighting device according to the present invention as described with reference to FIG. 6(A) was installed. A television set 902 can be installed to watch public broadcasts and movies.

[0192] In the fifth embodiment, the configurations shown in the first to fourth embodiments are appropriately combined. It may be used. [Example]

[0193] <Synthesis Example 1> In this example, a full-formula compound, which is one embodiment of the present invention shown in Embodiment 1 as general formula (G1), was used. A synthesis example of a diol derivative is shown below. Specifically, the 4-diol derivative shown in the structural formula (101) of the first embodiment is -phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: The synthesis method of BPAFLP is explained below. The structure of BPAFLP is shown below.

[0194] [ka]

[0195] [Step 1: Synthesis of 9-(4-bromophenyl)-9-phenylfluorene] In a 100 mL three-neck flask, add 1.2 g (50 mmol) of magnesium and dissolve it under reduced pressure for 30 minutes. The mixture was heated and stirred for 1 minute to activate the magnesium. After cooling to room temperature and placing in a nitrogen atmosphere, A few drops of dibromoethane were added and it was confirmed that foaming and heat were generated. 12 g (50 mmol) of 2-bromobiphenyl dissolved in 10 mL of ethanol was slowly added dropwise. After that, the mixture was heated under reflux with stirring for 2.5 hours to form a Grignard reagent.

[0196] 10 g (40 mmol) of 4-bromobenzophenone and 100 g of dehydrated diethyl ether The Grignard reagent synthesized earlier was slowly added to the 500 mL three-neck flask. After the dropwise addition, the mixture was heated under reflux and stirred for 9 hours.

[0197] After the reaction, the mixture was filtered to obtain a residue. The residue was dissolved in 150 mL of ethyl acetate. However, 1N hydrochloric acid was added to the solution until it became acidic, and the mixture was stirred for 2 hours. The part was washed with water and dried by adding magnesium sulfate. The suspension was filtered. The obtained filtrate was concentrated to give a candy-like substance.

[0198] Next, add this syrup, 50 mL of glacial acetic acid, and 1 mL of hydrochloric acid to a 500 mL eggplant flask. The mixture was heated and stirred at 130°C for 1.5 hours under a nitrogen atmosphere to allow the reaction to proceed.

[0199] After the reaction, the reaction mixture was filtered to obtain a residue. The residue was then washed with water, sodium hydroxide, and After washing with water, water, and methanol in that order, the product was dried to obtain a white powder with a yield of 11 g and a yield of 1. The reaction scheme of the above synthesis method is shown in (J-1) below.

[0200] [ka]

[0201] [Step 2: 4-phenyl-4'-(9-phenylfluoren-9-yl)triphenyl Synthesis of BPAFLP] In a 100 mL three-neck flask, add 9-(4-bromophenyl)-9-phenylfluorene. 3.2 g (8.0 mmol), 4-phenyl-diphenylamine 2.0 g (8.0 mmol) ol), sodium tert-butoxide 1.0g (10mmol), bis(dibenzoyl) Add 23 mg (0.04 mmol) of diphenyldiphenylacetone palladium(0) to the flask. The atmosphere was replaced with nitrogen. 20 mL of dehydrated xylene was added to this mixture. After degassing under reduced pressure with stirring, tri(tert-butyl)phosphine (10 wt% 0.2 mL (0.1 mmol) of a hexane solution was added to the mixture. The mixture was heated and stirred at 110°C for 2 hours to cause a reaction.

[0202] After the reaction, 200 mL of toluene was added to the reaction mixture, and the suspension was The solution was filtered through a light filter (Wako Pure Chemical Industries, Ltd., Cat. No. 531-16855). The obtained filtrate was concentrated and purified by silica gel column chromatography (developing solvent: toluene, The resulting fraction was concentrated and purified with acetone and methanol (hexane = 1:4). After adding ethanol and applying ultrasound, recrystallization was performed to obtain the desired white powder in a yield of 4. The reaction scheme of the above synthesis method is shown in (J-2) below.

[0203] [ka]

[0204] Rf values ​​in silica gel thin layer chromatography (TLC) (eluent: ethyl acetate:hexane) The target compound was 0.41, 9-(4-bromophenyl)-9-phenyl Fluorene was 0.51 and 4-phenyl-diphenylamine was 0.27.

[0205] The compound obtained in step 2 above was measured by nuclear magnetic resonance (NMR). The constant data is shown. 1 The 1 H NMR chart is shown in Figure 10. From the measurement results, the above structure The fluorene derivative of the present invention, BPAFLP (abbreviation), represented by the formula (101) was obtained. It was found that

[0206] 1 H NMR(CDCl3,300MHz):δ(ppm)=6.63-7.02(m , 3H), 7.06-7.11(m, 6H), 7.19-7.45(m, 18H), 7. 53-7.55(m, 2H), 7.75(d, J=6.9, 2H).

[0207] In addition, various physical properties of the obtained target substance, BPAFLP (abbreviation), were measured as follows: did.

[0208] The absorption spectrum (measurement range 200 nm to 800 nm) was measured using a UV-visible spectrophotometer (Japan The absorption spectra of the toluene solution and thin film are shown in Figure 11. The horizontal axis represents wavelength (nm) and the vertical axis represents absorption intensity (arbitrary units). The liquid was measured in a quartz cell, and the absorption spectrum of quartz and toluene was subtracted. The absorption spectrum of the thin film was measured by depositing it on a quartz substrate. The spectra from which the absorption peak on the long wavelength side was subtracted are shown. is observed around 324 nm in the toluene solution and around 314 nm in the thin film. I found out that I could see it.

[0209] The emission spectrum was measured using a fluorometer (FS920 manufactured by Hamamatsu Photonics Co., Ltd.). Figure 12 shows the emission spectra of the toluene solution and the thin film. The horizontal axis is wavelength (nm) and the vertical axis is represents the emission intensity (arbitrary unit). The toluene solution was measured in a quartz cell, and the thin film was measured in a quartz cell. The sample deposited on the substrate was measured. From these spectra, the maximum emission wavelength was For solutions, the excitation wavelength is 386 nm (excitation wavelength 330 nm), and for thin films, the excitation wavelength is 400 nm (excitation wavelength It was found that the wavelength was 349 nm.

[0210] The thin film was measured in air by photoelectron spectroscopy (Riken Keiki, AC-2). The absorption edge was -5.63 eV. From the Tauc plot of the absorption spectrum of the thin film, Therefore, the energy gap in the solid state is estimated to be 3.34 eV. This means that the LUMO level is -2.29 eV. BPAFLP (abbreviation) has a relatively deep HOMO level and a wide band gap (Bg ) was found to have

[0211] The redox reaction characteristics were investigated by cyclic voltammetry (CV) measurements. The electrochemical analyzer (manufactured by BAS Co., Ltd., model number: ALS model 600A) or 600C) was used.

[0212] The oxidation reaction characteristics were measured by varying the potential of the working electrode relative to the reference electrode from -0.10 V to 1.50 V. After scanning, the voltage was scanned from 1.50 V to -0.10 V. The oxidation peak was found to be -5.51 eV. This indicates that the repetition of oxidation-reduction between the oxidized and neutral states is favorable. It was found that it exhibits excellent properties.

[0213] The measurement method will be described in detail below.

[0214] (Calculation of potential energy relative to the vacuum level of the reference electrode) First, the reference electrode (Ag / Ag + potential of the electrode relative to the vacuum level The electron energy (eV) was calculated. + The Fermi level of the electrode was calculated. The redox potential of ferrocene in methanol is +0.61 vs. the standard hydrogen electrode. 0 [V vs. SHE] (references; Christian R.Goldsmith et al., J.Am.Chem.Soc., Vol. 124, No.1, 83-96, 2002). On the other hand, the reference electrode used in this example The oxidation-reduction potential of ferrocene in methanol was found to be +0.11 V[ vs. Ag / Ag + Therefore, the potential energy of this reference electrode is It was found that the potential was 0.50 eV lower than that of the standard hydrogen electrode.

[0215] Here, the potential energy of the standard hydrogen electrode from the vacuum level is -4.44 eV. It is known that (Reference: Toshihiro Onishi and Tamami Koyama, Polymer EL Materials (Kyoritsu Shuppan) , p.64-67). From the above, the potential of the reference electrode used with respect to the vacuum level is The energy was calculated to be -4.44-0.50=-4.94[eV].

[0216] (CV measurement conditions for the target object) The solution used in the CV measurement was dehydrated dimethylformamide (DMF) (Asahi Chemical Industries, Ltd.). The supporting electrolyte was 0.1% sucrose (manufactured by Rudrich, 99.8%, catalog number: 22705-6). Tetra-n-butylammonium perchlorate (n-Bu4NClO4) (Tokyo Chemical Industry Co., Ltd.) Catalog number: T0836) was dissolved to a concentration of 100 mmol / L, and The measurement target was dissolved to a concentration of 2 mmol / L. A platinum electrode (PTE platinum electrode, manufactured by BAS Co., Ltd.) was used as the electrode, and a platinum electrode (PTE platinum electrode, manufactured by BAS Co., Ltd.) was used as the auxiliary electrode. The electrode (Pt counter electrode (5 cm) for VC-3, manufactured by BAS Co., Ltd.) was used as a reference. Ag / Ag electrodes + Electrode (BAS Co., Ltd., RE7 non-aqueous solvent reference electrode) The measurements were carried out at room temperature (20-25°C). The scan rate was set to 0.1 V / sec.

[0217] Next, the HOMO level was calculated from this CV measurement. The CV measurement results of the oxidation reaction characteristics are shown in Figure 1. As shown in Figure 13, the oxidation peak potential (from the neutral side to the oxidation side) E pa is 0.6 The reduction peak potential (from the oxidation side to the neutral side) E pc was 0.52V Therefore, the half-wave potential (E pa and E pc The intermediate potential between Epa and Epc (Epa+Epc) / 2[V] This means that 0.57 V vs. Ag / Ag + ] Electric As mentioned above, the reference electrode used The potential energy relative to the vacuum level is -4.94 eV, so BPAF The HOMO level of LP (abbreviation) is -4.94-0.57=-5.51[eV] I found out.

[0218] The glass transition temperature was measured using a differential scanning calorimeter (DSC, manufactured by PerkinElmer Co., Ltd.). The measurement results showed that the glass transition temperature was 107°C. It was found that the cellulose exhibited a high glass transition temperature and good heat resistance. No peak was observed, indicating that the substance is difficult to crystallize. [Example]

[0219] <Synthesis Example 2> In this example, a full-formula compound, which is one embodiment of the present invention shown in Embodiment 1 as general formula (G1), was used. A synthesis example of a diol derivative is shown below. Specifically, the 4-diol derivative shown in the structural formula (151) of the first embodiment is -phenyl-4'-[4-(9-phenylfluoren-9-yl)phenyl]tripheny The synthesis method of diphenylamine (abbreviated as BPAFLBi) is explained below. is shown below.

[0220] [ka]

[0221] Step 1: Synthesis of 9-(4'-bromo-4-biphenyl)-9-phenylfluorene Law] Put 5.1 g (22 mmol) of 2-bromobiphenyl into a 500 mL three-neck flask. After replacing the atmosphere in the flask with nitrogen, 20 1.59 mol / L n-butyllithium was added to this mixture and the temperature was kept at -78°C. 14 mL (22 mmol) of hexane solution was added dropwise and stirred for 2.5 hours. Add 6.7 g (20 mmol) of benzoyl-4'-bromobiphenyl and heat at -78°C. The mixture was stirred for 2 hours and then at room temperature for 85 hours.

[0222] After the reaction, 1N diluted hydrochloric acid was added to the reaction solution until it became acidic, and the mixture was stirred for 4 hours. The suspension was washed with water. After washing, magnesium sulfate was added to remove the water. The suspension was filtered. The resulting filtrate was concentrated and purified by silica gel column chromatography (developing solvent: toluene). The resulting fraction was concentrated and purified with methanol. After adding the compound and applying ultrasonic waves, the mixture was recrystallized to obtain a white powder of the desired product.

[0223] Next, add this white powder, 50 mL of glacial acetic acid, and 1.5 mL of hydrochloric acid to a 200 mL recovery flask. The mixture was heated and stirred at 130°C for 2.5 hours under a nitrogen atmosphere to allow the reaction to proceed.

[0224] After the reaction, the reaction mixture was filtered to obtain a residue. The residue was then diluted with 100 mL of toluene. Dissolve in water, wash with water, sodium hydroxide solution, and water in that order, add magnesium sulfate to remove moisture. The suspension was filtered, and the resulting filtrate was concentrated, to which acetone and methanol were added. After applying ultrasonic waves, the target white powder was obtained in an amount of 6.3 g and a yield of 67%. %. The reaction scheme is shown in (J-3) below.

[0225] [ka]

[0226] [Step 2: 4-phenyl-4'-[4-(9-phenylfluoren-9-yl)phenyl] Synthesis of [Nyl]triphenylamine (abbreviation: BPAFLBi) In a 100 mL three-neck flask, add 9-(4'-bromo-4-biphenyl)-9-phenylfluorene. 3.8 g (8.0 mmol) of fluorene and 2.0 g ( 8.0 mmol), sodium tert-butoxide 1.0 g (10 mmol), Add 23 mg (0.04 mmol) of bis(dibenzylideneacetone)palladium(0) The atmosphere in the flask was replaced with nitrogen. 20 mL of dehydrated xylene was added to this mixture. The mixture was degassed under reduced pressure while stirring, and then tri(tert-butyl)phosphine ( 0.2 mL (0.1 mmol) of a 10 wt% hexane solution was added to the mixture. The mixture was heated and stirred at 110°C under atmospheric pressure for 2 hours to carry out the reaction.

[0227] After the reaction, 200 mL of toluene was added to the reaction mixture, and the suspension was The resulting filtrate was concentrated and purified by silica gel column chromatography. The resulting fraction was purified using a developing solvent of toluene:hexane = 1:4. The concentrate was added with acetone and methanol, and after ultrasonic treatment, the desired product was recrystallized. The product was obtained as a white powder in 4.4 g and a yield of 86%. The details are shown in (J-4).

[0228] [ka]

[0229] Rf values ​​in silica gel thin layer chromatography (TLC) (eluent: ethyl acetate:hexane) The target compound was 0.51, 9-(4'-bromo-4-biphenyl)-9 -phenylfluorene was 0.56, and 4-phenyl-diphenylamine was 0.28.

[0230] The compound obtained in step 2 above was measured by nuclear magnetic resonance (NMR). The constant data is shown. 1 The 1 H NMR chart is shown in Figure 14. From the measurement results, it is clear that the above structure The fluorene derivative of the present invention, BPAFLBi (abbreviation), represented by the formula (151) was obtained. It was found that

[0231] 1 H NMR (CDCl3,300MHz): δ(ppm)=7.04(t, J=6. 6, 1H), 7.12-7.49(m, 30H), 7.55-7.58(m, 2H), 7 .77 (d, J = 7.8, 2H).

[0232] In addition, various physical properties of the obtained target substance, BPAFLBi (abbreviation), were measured as follows. It was determined.

[0233] The absorption spectrum (measurement range 200 nm to 800 nm) was measured using a UV-visible spectrophotometer (Japan Spectroscopy) The absorption spectra of the toluene solution and thin film are shown in Figure 15. The horizontal axis represents wavelength (nm) and the vertical axis represents absorption intensity (arbitrary units). Toluene solution is the spectrum measured in a quartz cell, after subtracting the absorption spectra of quartz and toluene. The absorption spectrum of the thin film was measured by measuring a sample deposited on a quartz substrate. The spectra after subtracting the absorption peaks are shown in the figure. In the case of the toluene solution, it is seen around 340 nm, and in the case of the thin film, it is seen around 341 nm. It was found that this could be done.

[0234] The emission spectrum was measured using a fluorometer (FS920 manufactured by Hamamatsu Photonics Co., Ltd.). Figure 16 shows the emission spectra of the toluene solution and the thin film. The horizontal axis is wavelength (nm) and the vertical axis is represents the emission intensity (arbitrary unit). The toluene solution was measured in a quartz cell, and the thin film was measured in a quartz cell. The sample deposited on the substrate was measured. From these spectra, the maximum emission wavelength was 386 nm (excitation wavelength 345 nm) for solutions, 399 and 419 nm for thin films (The excitation wavelength was found to be 348 nm.

[0235] The thin film was measured in air by photoelectron spectroscopy (Riken Keiki, AC-2). The absorption edge was -5.64 eV. From the Tauc plot of the absorption spectrum of the thin film, Therefore, the energy gap in the solid state is estimated to be 3.28 eV. This means that the LUMO level is -2.36 eV. BPAFLBi (abbreviation) has a relatively deep HOMO level and a wide band gap (B g).

[0236] The redox reaction characteristics were investigated by cyclic voltammetry (CV) measurements. The electrochemical analyzer (manufactured by BAS Co., Ltd., model number: ALS model 600A) The measurement method was the same as in Example 1, so the explanation will be omitted. do.

[0237] The oxidation reaction characteristics were measured by varying the potential of the working electrode relative to the reference electrode from -0.10 V to 1.50 V. After scanning, the voltage was scanned from 1.50 V to -0.10 V. The oxidation peak was found to be -5.49 eV. This indicates that the repetition of oxidation-reduction between the oxidized and neutral states is favorable. It was found that it exhibits excellent properties.

[0238] The CV measurement results of the oxidation reaction characteristics are shown in FIG.

[0239] The glass transition temperature was measured using a differential scanning calorimeter (DSC, manufactured by PerkinElmer Co., Ltd.). The measurement results showed that the glass transition temperature was 126°C. It was found that the cellulose exhibited a high glass transition temperature and good heat resistance. No peak was observed, indicating that the substance is difficult to crystallize. [Example]

[0240] In this example, the fluorene derivative 4-phenyl-4'-(9 -phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP) The fabrication method of the formed light-emitting element and the measurement results of the element characteristics are shown.

[0241] The element structure of the light-emitting element in this example is the structure shown in FIG. The hole transport layer 1512 contains the fluorene derivative of the present invention (abbreviation: BPAFLP). The comparative light-emitting element 1 is formed using a hole-transporting layer 151. 2 to 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB) was used to form the light-emitting element 2 on the same substrate in order to make the comparison conditions uniform. A comparative light-emitting element 1 was formed on the substrate and compared with the light-emitting element 2. The structural formula of the organic compound is shown below.

[0242] [ka]

[0243] First, on the substrate 1501, which is a glass substrate, indium oxide-tin oxide containing silicon oxide is formed. The first electrode 1502 was formed by sputtering. The thickness was set to 10 nm and the electrode area was set to 2 mm x 2 mm.

[0244] Next, an EL layer 1503 in which a plurality of layers are stacked is formed on the first electrode 1502. In Example 5, the EL layer 1503 includes a first layer 1511 which is a hole injection layer, a second layer 1512 which is a hole transport layer, and a third layer 1513 which is a hole transport layer. a second layer 1512 which is a light-emitting layer, a third layer 1513 which is a light-emitting layer, and a fourth layer 1514 which is an electron transport layer. 14 and a fifth layer 1515 which is an electron injection layer are laminated in this order.

[0245] The first electrode 1502 is formed so that the surface on which the first electrode 1502 is formed faces downward. The substrate was fixed to a substrate holder installed in a vacuum deposition apparatus, and -4 Reduced to about Pa After the pressure application, 4,4′-bis[N-(1-naphthyl)-N-phenylene] is deposited on the first electrode 1502. co-evaporation of [nylamino]biphenyl (abbreviation: NPB) and molybdenum (VI) oxide The first layer 1511, which is a hole injection layer, was formed by the above method. The weight ratio of B to molybdenum (VI) oxide is 4:1 (NPB: molybdenum oxide). The deposition rate was adjusted so that the deposition rate was 100%. This is a deposition method in which deposition and film formation occur simultaneously.

[0246] Next, a hole transporting material is deposited on the first layer 1511 by a vapor deposition method using resistance heating. The second layer 1512, which is a hole transporting layer, was formed to a thickness of 1000 μm. When forming the light emitting element 1, 4,4'-bis[N-(1-naphthyl)-N-phenyl] When the light-emitting element 2 is formed using 4-fluoro-2-phenyl-4-aminobiphenyl (abbreviation: NPB), Phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: BP AFLP) were used to generate the respective sequences.

[0247] Next, a third layer (a light-emitting layer) is formed on the second layer 1512 by a vapor deposition method using resistance heating. Formation of 1513: 9-[4-(10-phenyl-9-anthryl)phenyl]-9H -carbazole (abbreviation: CzPA) and 4-(10-phenyl-9-anthryl)-4'- (9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBA The third layer 1513 was formed to a thickness of 30 nm by co-evaporation of SiO 2 and PA. The weight ratio of CzPA to PCBAPA was 1:0.10 (CzPA:PCBAPA). The deposition rate was adjusted so that

[0248] Furthermore, tris(8-quinolinol) was deposited on the third layer 1513 by using a vapor deposition method using resistance heating. A 10 nm layer of (tetrahydro)aluminum(III) (abbreviation: Alq) was deposited on it, and bathophenanthro Phosphorus (abbreviation: BPhen) was formed to a thickness of 20 nm, and the fourth electron transport layer was formed. A layer 1514 was formed.

[0249] On the fourth layer 1514, a lithium fluoride (LiF) film is formed to a thickness of 1 nm. In this way, a fifth layer 1515 serving as an electron injection layer was formed.

[0250] Finally, aluminum was evaporated to a thickness of 200 nm using resistance heating. The second electrode 1504 was formed by film deposition, and the comparative light-emitting element 1 and the light-emitting element 2 were fabricated. did.

[0251] The comparative light-emitting element 1 and the light-emitting element 2 were fabricated in the same process except for the second layer 1512. are.

[0252] The comparative light-emitting element 1 and the light-emitting element 2 obtained above were placed in a glove box in a nitrogen atmosphere. After sealing the light-emitting elements in the chamber to prevent them from being exposed to the atmosphere, The operating characteristics of the optical element were measured. The measurements were carried out at room temperature (an atmosphere maintained at 25°C). So I went.

[0253] FIG. 19 shows the current density-luminance characteristics of the comparative light-emitting element 1 and the light-emitting element 2. The luminance characteristics are shown in Figure 20, and the luminance-current efficiency characteristics are shown in Figure 21. degree (cd / m 2 ), and the horizontal axis is the current density (mA / cm 2 ) and in Figure 20, the vertical axis indicates brightness (c d / m 2 ), and the horizontal axis shows voltage (V). In Figure 21, the vertical axis shows current efficiency (cd / A) and the horizontal axis shows to luminance (cd / m 2 ) and 1000cd / cm 2 The voltage of the light-emitting element in the vicinity The chromaticity and current efficiency are shown in Table 1.

[0254] [Table 1]

[0255] Light-emitting element 2 has a luminance of 880 cd / m when the driving voltage is 4.2 V. 2 , the current value is 0.41 mA. It was found that the light-emitting element 2 using BPAFLP (abbreviation) for the layer 1512 had high current efficiency. This is because the carrier balance of Light-emitting element 2 is improved compared to that of Light-emitting element 1. This is because the HOMO level of BPAFLP (abbreviation) is higher than that of NPB. Since the HOMO level is close to that of CzPA (abbreviation), the host material of the optical layer, light is emitted from the hole transport layer. This is thought to be due to the improved hole injection into the layer. Because the LUMO level of PAFLP (abbreviation) is high, electron blocking from the light-emitting layer to the hole transport layer is This is thought to be due to the improved binding ability. The band gap (Bg) of the third layer 1513 (light-emitting layer) is wide, so the excitation current generated in the third layer 1513 The electrons are trapped (not quenched) in the adjacent second layer 1512. This is thought to be because [Example]

[0256] In this example, the fluorene derivative 4-phenyl-4'-(9 -phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP) The fabrication method of the formed light-emitting element and the measurement results of the element characteristics are shown.

[0257] The element structure of the light-emitting element 3 in this example is the structure shown in FIG. 18, and the hole transport The layer 1512 is formed using the fluorene derivative (abbreviation: BPAFLP) of the present invention. The structural formulas of the organic compounds used in this example are shown below.

[0258] [ka]

[0259] First, on the substrate 1501, which is a glass substrate, indium oxide-tin oxide containing silicon oxide is formed. The first electrode 1502 was formed by sputtering. The thickness was set to 10 nm and the electrode area was set to 2 mm x 2 mm.

[0260] Next, an EL layer 1503 in which a plurality of layers are stacked is formed on the first electrode 1502. In the example, the EL layer 1503 comprises a first layer 1511 which is a hole injection layer, a second layer 1512 which is a hole transport layer, and a third layer 1513 which is a hole transport layer. The second layer 1512 is a light-emitting layer, the third layer 1513 is a light-emitting layer, and the fourth layer 1514 is an electron transport layer. 4 and a fifth layer 1515, which is an electron injection layer, are laminated in this order.

[0261] The first electrode 1502 is formed so that the surface on which the first electrode 1502 is formed faces downward. The substrate was fixed to a substrate holder installed in a vacuum deposition apparatus, and -4 Reduced to about Pa After applying pressure, 9-[4-(10-phenyl-9-anthryl)fluoride] is applied to the first electrode 1502. CzPA and molybdenum(VI) oxide were co-evaporated. The first layer 1511, which is a hole injection layer, was formed by this process. The film thickness of the first layer 1511 was 50 nm. The weight ratio of CzPA to molybdenum (VI) oxide was 4:1 (CzPA:molybdenum oxide). The deposition rate was adjusted so that the deposition temperature was 100°C.

[0262] Next, a hole transporting material is deposited on the first layer 1511 by a vapor deposition method using resistance heating. The second layer 1512 was formed as a hole transport layer. When forming the optical element 3, 4-phenyl-4'-(9-phenylfluorene-9-yl) The compound was formed using BPAFLP.

[0263] Next, a third layer (a light-emitting layer) is formed on the second layer 1512 by a vapor deposition method using resistance heating. Formation of 1513: 9-[4-(10-phenyl-9-anthryl)phenyl]-9H -carbazole (abbreviation: CzPA) and 4-(10-phenyl-9-anthryl)-4'- (9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBA The third layer 1513 was formed to a thickness of 30 nm by co-evaporation of SiO 2 and PA. The weight ratio of CzPA to PCBAPA was 1:0.10 (CzPA:PCBAPA). The deposition rate was adjusted so that

[0264] Thereafter, in the same manner as in the comparative light-emitting element 1, a fourth layer serving as an electron transport layer and a fifth layer serving as an electron injection layer were formed. A layer and a second electrode were formed, and Light-emitting element 3 was fabricated.

[0265] The light-emitting element 3 obtained as described above was placed in a glove box with a nitrogen atmosphere. After sealing the element to prevent it from being exposed to the atmosphere, the operating characteristics of the light-emitting element 3 were measured. The measurements were carried out at room temperature (an atmosphere maintained at 25°C).

[0266] FIG. 22 shows the current density-luminance characteristics of the light-emitting element 3. FIG. 23 shows the voltage-luminance characteristics. The luminance-current efficiency characteristics are shown in Figure 24. In Figure 22, the vertical axis shows the luminance (cd / m 2 ),beside The axis shows the current density (mA / cm 2 ) and in Figure 23, the vertical axis shows luminance (cd / m2 ), and the horizontal axis is the voltage In Figure 24, the vertical axis shows the current efficiency (cd / A) and the horizontal axis shows the luminance (cd / m 2 ) Also, 1000cd / m 2 The voltage, chromaticity, and current efficiency of the light-emitting element in the vicinity are shown in Table 2. Shown below.

[0267] [Table 2]

[0268] In this example, a fluorene derivative (abbreviation: BPAFLP) of the present invention was used to form a It was confirmed that the light-emitting element had the characteristics required for a light-emitting element and functioned satisfactorily. The test results showed that even when the light-emitting element was continuously lit, short circuits caused by defects in the film, etc. It was found that no defects occurred and a highly reliable light-emitting element was obtained.

[0269] Regarding the light-emitting element 3, the initial luminance is set to 1000 cd / cm 2 As a result, low current drive The results of the continuous lighting test are shown in Figure 25 (the vertical axis is 1000 cd / cm 2 100% The results in FIG. 25 show that Light-emitting element 3 maintained its initial brightness even after 1000 hours. The brightness of the BPA lamp of the present invention was maintained at 78% of the original brightness, demonstrating its long life. It has been found that by applying FLP (abbreviation), it is possible to obtain a light-emitting element with a long life. It was. [Example]

[0270] In this example, the fluorene derivative 4 of the present invention synthesized in Example 1 and Example 2 was -phenyl-4'-[4-(9-phenylfluoren-9-yl)phenyl]tripheny A light-emitting element formed using 4-phenyl-4'-( 9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP) The fabrication method of the light-emitting element formed by this method and the results of the element characteristics are shown below.

[0271] The element structure of the light-emitting element in this example is the structure shown in FIG. 18, and the hole injection layer The hole transport layer is formed using the fluorene derivative of the present invention. The structural formula of the organic compound used in Example 5 is shown below.

[0272] [ka]

[0273] First, on the substrate 1501, which is a glass substrate, indium oxide-tin oxide containing silicon oxide is formed. The first electrode 1502 was formed by sputtering. The thickness was set to 0 nm and the electrode area was set to 2 mm x 2 mm.

[0274] Next, an EL layer 1503 in which a plurality of layers are stacked is formed on the first electrode 1502. In the example, the EL layer 1503 comprises a first layer 1511 which is a hole injection layer, a second layer 1512 which is a hole transport layer, and a third layer 1513 which is a hole transport layer. The second layer 1512 is a light-emitting layer, the third layer 1513 is a light-emitting layer, and the fourth layer 1514 is an electron transport layer. 4 and a fifth layer 1515, which is an electron injection layer, are laminated in this order.

[0275] The first electrode 1502 is formed so that the surface on which the first electrode 1502 is formed faces downward. The substrate was fixed to a substrate holder installed in a vacuum deposition apparatus, and -4 Reduced to about Pa After the pressure application, a fluorene derivative and a molybdenum oxide film according to one embodiment of the present invention were applied to the first electrode 1502. The first layer 1511, which is a hole injection layer, was formed by co-evaporation with butanol (VI). The film thickness is 50 nm, and the ratio of the fluorene derivative to molybdenum (VI) oxide is The deposition rate was adjusted so that the weight ratio was 4:1 (fluorene derivative:molybdenum oxide). In the case where the light-emitting element 4 is formed, the fluorene derivative is 4-phenylene. Nyl-4'-[4-(9-phenylfluoren-9-yl)phenyl]triphenylamine When the light-emitting element 5 is formed using 4-phenyl-4-phenylpropanol (abbreviation: BPAFLBi), '-(9-Phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP) were formed using

[0276] Next, a hole transport material was deposited on the first layer to a thickness of 10 nm by a vapor deposition method using resistance heating. The second layer 1512, which is a hole transport layer, was formed. When forming the light emitting element 5, BPAFLBi is used. Each was formed using P.

[0277] Next, a third layer (a light-emitting layer) is formed on the second layer 1512 by a vapor deposition method using resistance heating. In this example, the light-emitting layer was formed as two layers. CzPA and 4- (10-phenyl-9-anthryl)-4'-(9-phenyl-9H-carbazole-3 The second A first light-emitting layer was formed on the layer 1512 to a thickness of 15 nm. The weight ratio of CzPA to PA was 1:0.10 = (CzPA:PCBAPA) was adjusted.

[0278] Next, a second light-emitting layer was formed on the first light-emitting layer by a vapor deposition method using resistance heating. -[4-(10-phenyl-9-anthryl)phenyl]-9H-carbazole (abbreviation: CzPA) and 4-(10-phenyl-9-anthryl)-4'-(9-phenyl-9H- carbazol-3-yl)triphenylamine (abbreviation: PCBAPA) Thus, a first light-emitting layer was formed on the second layer 1512 to a thickness of 15 nm. The weight ratio of zPA to PCBAPA was 1:0.05 = (CzPA:PCBAPA). The deposition rate was adjusted so that

[0279] Thereafter, in the same manner as in the comparative light-emitting element 1, a fourth layer serving as an electron transport layer and a fifth layer serving as an electron injection layer were formed. A layer and a second electrode were formed, respectively, to fabricate light-emitting elements 4 and 5.

[0280] The light-emitting elements 4 and 5 are formed by layers other than the first layer 1511 and the second layer 1512. are made in the same process.

[0281] The light-emitting elements 4 and 5 obtained as described above were placed in a glove box under a nitrogen atmosphere. After sealing the light emitting elements in the container to prevent them from being exposed to the atmosphere, The operating characteristics of the device were measured. The measurements were carried out at room temperature (an atmosphere maintained at 25°C). went.

[0282] FIG. 26 shows current density-luminance characteristics of Light-emitting Elements 4 and 5. The characteristics are shown in Figure 27, and the luminance-current efficiency characteristics are shown in Figure 28. In Figure 26, the vertical axis shows the luminance ( cd / m 2 ), and the horizontal axis is the current density (mA / cm2 ) and in Figure 27, the vertical axis shows the luminance (cd / m 2 ), and the horizontal axis shows voltage (V). In Figure 28, the vertical axis shows current efficiency (cd / A) and the horizontal axis shows luminance. degree (cd / m 2 ) and 1000cd / m 2 Voltage and chromaticity of the light-emitting element in the vicinity The current efficiency and external quantum efficiency are shown in Table 3.

[0283] [Table 3]

[0284] In this example, a luminescent element formed using BPAFLBi (abbreviation) and BPAFLP was It was confirmed that the device had the characteristics required for a light-emitting device and functioned satisfactorily. The results show that even when the light-emitting element is continuously lit, short circuits due to defects in the film do not occur. It was found that a highly reliable light-emitting element was obtained without any problem.

[0285] Furthermore, for the light-emitting elements 4 and 5, the initial luminance was 1000 cd / cm 2 As, The results of a continuous lighting test using low current drive are shown in Figure 29 (the vertical axis is 1000 cd / c m 2 The results of FIG. 29 show that the light-emitting element 4 exhibited a luminance of 850 s.p.m. Light-emitting element 5 maintained 74% of its initial brightness even after 850 hours, and light-emitting element 6 maintained 75% of its initial brightness even after 850 hours. Therefore, it was found that the BPAFLBi (abbreviation) and It has been found that by applying BPAFLP (abbreviation), a long-life light-emitting element can be obtained. It was. [Example]

[0286] In this example, the fluorene derivative of the present invention, 4-phenyl-4 '-(9-Phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP) The fabrication method of a light-emitting element formed using the above and the results of the element characteristics are shown below.

[0287] The element structure of the light-emitting element in this example is the structure shown in FIG. 18. The hole transport layer is formed using the fluorene derivative of the present invention. The structural formulae of the organic compounds used in the examples are shown below.

[0288] [ka]

[0289] First, on the substrate 1501, which is a glass substrate, indium oxide-tin oxide containing silicon oxide is formed. The first electrode 1502 was formed by sputtering. The thickness was set to 10 nm and the electrode area was set to 2 mm x 2 mm.

[0290] Next, an EL layer 1503 in which a plurality of layers are stacked is formed on the first electrode 1502. In Example 5, the EL layer 1503 includes a first layer 1511 which is a hole injection layer, a second layer 1512 which is a hole transport layer, and a third layer 1513 which is a hole transport layer. a second layer 1512 which is a light-emitting layer, a third layer 1513 which is a light-emitting layer, and a fourth layer 1514 which is an electron transport layer. 14 and a fifth layer 1515 which is an electron injection layer are laminated in this order.

[0291] The first electrode 1502 is formed so that the surface on which the first electrode 1502 is formed faces downward. The substrate was fixed to a substrate holder installed in a vacuum deposition apparatus, and -4 Reduced to about Pa After the pressure application, 4,4′-bis[N-(1-naphthyl)-N-phenylene] is deposited on the first electrode 1502. co-evaporation of [nylamino]biphenyl (abbreviation: NPB) and molybdenum (VI) oxide The first layer 1511, which is a hole injection layer, was formed by the above method. The weight ratio of B to molybdenum (VI) oxide is 4:2 = (NPB:molybdenum oxide). The deposition rate was adjusted so that the deposition rate was 100%. This is a deposition method in which deposition is carried out simultaneously from

[0292] Next, a hole transporting material is deposited on the first layer 1511 by a vapor deposition method using resistance heating. The second layer 1512 was formed as a hole transport layer. When forming the optical element 6, 4-phenyl-4'-(9-phenylfluorene-9-yl) In the case where comparative light-emitting element 7 is formed using triphenylamine (abbreviation: BPAFLP), The compound contains 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviated as :NPB).

[0293] Next, a third layer (a light-emitting layer) is formed on the second layer 1512 by a vapor deposition method using resistance heating. 1513 was formed. 3-phenyl-9-[4-(5-phenyl-1,3,4-oxazolidinyl]-2-methyl-2-(2-methyl- ... Azol-2-yl)phenyl]-9H-carbazole (abbreviation: CO11II) and (2- Phenylpyridinato-N,C 2’ ) Iridium(III) acetylacetonate (abbreviation: The third layer 913 was formed to a thickness of 40 nm by co-evaporation with Ir(ppy)2acac. Here, the weight ratio of CO11II to Ir(ppy)2acac was 1:0. The evaporation rate was adjusted so that O8 = (CO11II:Ir(ppy)2acac). .

[0294] Furthermore, bis(2-methyl-8-phenylene ether) was deposited on the third layer 1513 by using a vapor deposition method using resistance heating. -quinolinolato)(4-phenylphenolato)aluminum(III) (abbreviation: BAlq ) to a thickness of 10 nm, and then bathophenanthroline (abbreviation: BPhen) was applied to a thickness of 20 nm. A fourth layer 1514 serving as an electron transporting layer was formed.

[0295] Thereafter, in the same manner as in the comparative light-emitting element 1, a fourth layer serving as an electron transport layer and a fifth layer serving as an electron injection layer were formed. A layer and a second electrode were formed, and thus the light-emitting element 6 and the comparative light-emitting element 7 were fabricated.

[0296] The light-emitting element 6 and the comparative light-emitting element 7 were fabricated in the same process except for the second layer 1512. There are.

[0297] The light-emitting element 6 and the comparative light-emitting element 7 obtained above were placed in a glove box with a nitrogen atmosphere. After sealing the light emitting elements in the container to prevent them from being exposed to the atmosphere, The operating characteristics of the device were measured. The measurements were carried out at room temperature (an atmosphere maintained at 25°C). went.

[0298] 30 shows current density-luminance characteristics of the light-emitting element 6 and the comparative light-emitting element 7. The characteristics are shown in Figure 31, and the luminance-current efficiency characteristics are shown in Figure 32. In Figure 30, the vertical axis shows the luminance ( cd / m 2 ), and the horizontal axis is the current density (mA / cm 2 ) and in Figure 31, the vertical axis shows the luminance (cd / m 2 ), and the horizontal axis shows voltage (V). In Figure 32, the vertical axis shows current efficiency (cd / A) and the horizontal axis shows luminance. degree (cd / m 2 ) and 1000cd / m 2 Voltage and chromaticity of the light-emitting element in the vicinity The current efficiency and external quantum efficiency are shown in Table 4.

[0299] [Table 4]

[0300] FIG. 33 shows emission spectra of the light-emitting element 6 and the comparative light-emitting element 7.

[0301] As shown in FIG. 33, in the comparative light-emitting element 7, in addition to the light emission from the dopant, The emission wavelengths originating from NPB were observed. This indicates that NPB has the ability to block electrons. This indicates that some recombination occurs even in NPBs with low internal quantum efficiency. As a result, the current efficiency and external quantum efficiency are thought to be low. Because of its low energy, triplet excitation energy in the emitting layer is transferred to NPB On the other hand, in the case of Light-emitting Device 6, the current efficiency and external quantum efficiency were reduced. Only the dopant-derived light emission in the light-emitting layer was observed, and the BPAFLP (abbreviation) in the hole-transporting layer Therefore, BPAFLP has a high electron blocking ability. Furthermore, it is suggested that the triplet excitation energy is also large. The electrons are mainly consumed by the phosphorescent dopant in the light-emitting layer and become light, resulting in high current efficiency. In this way, it can be said that BPAFLP (abbreviation), which is one embodiment of the present invention, is used as the hole transport layer. It was found that a highly efficient device can be obtained by using this. [Example]

[0302] In this Example 7, the fluorene derivative 4-phenyl-4'-( 9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP) The fabrication method of the light-emitting element formed by the above process and the measurement results of the element characteristics are shown below.

[0303] The element structures of the light-emitting elements 8 to 10 in this Example 7 are shown in FIG. 18. The light-emitting element 9 has the above-described present invention in the hole transport layer, and the light-emitting element 10 has the above-described present invention in the hole injection layer and hole transport layer. The organic compounds used in this Example 7 were prepared using the fluorene derivatives. The structural formula of the compound is shown below.

[0304] [ka]

[0305] First, on the substrate 1501, which is a glass substrate, indium oxide-tin oxide containing silicon oxide is formed. The first electrode 1502 was formed by sputtering. The thickness was set to 0 nm and the electrode area was set to 2 mm x 2 mm.

[0306] Next, an EL layer 1503 in which a plurality of layers are stacked is formed on the first electrode 1502. In the example, the EL layer 1503 comprises a first layer 1511 which is a hole injection layer, a second layer 1512 which is a hole transport layer, and a third layer 1513 which is a hole transport layer. The second layer 1512 is a light-emitting layer, the third layer 1513 is a light-emitting layer, and the fourth layer 1514 is an electron transport layer. 4 and a fifth layer 1515, which is an electron injection layer, are laminated in this order.

[0307] The first electrode 1502 is formed so that the surface on which the first electrode 1502 is formed faces downward. The substrate was fixed to a substrate holder installed in a vacuum deposition apparatus, and -4 Reduced to about Pa After pressing, a hole injection material was formed on the first electrode 1502 to a thickness of 50 nm. The first layer 1511, which is a hole injection layer, was formed. In the case of formation, 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl Hole injection was achieved by co-evaporating phenyl (abbreviation: NPB) and molybdenum (VI) oxide. The first layer 1511 was formed as a 50 nm thick layer. The ratio of NPB to molybdenum oxide was 4:2 by weight. In addition, when forming the light-emitting element 10, 4-phenyl-4'-(9- (Phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP) and molybdenum oxide The first layer 1511, which is a hole injection layer, is formed by co-evaporating fluoride (VI) and fluoride (VI). The film thickness was 50 nm, and the ratio of BPAFLP to molybdenum (VI) oxide was 100% by weight. The deposition rate was adjusted so that the ratio of BPAFLP to molybdenum oxide was 4:1.

[0308] Next, a hole transporting material is deposited on the first layer 1511 by a vapor deposition method using resistance heating. The second layer 1512 was formed as a hole transport layer. When forming the optical element 8, 4-phenyl-4'-(9-phenyl-9H-carbazole) The light-emitting element 9 and When forming the light emitting element 10, 4-phenyl-4'-(9-phenylfluorene- 9-yl)triphenylamine (abbreviation: BPAFLP), respectively.

[0309] Next, a third layer, which is a light-emitting layer, is formed on the second layer by a vapor deposition method using resistance heating. In this example, 3-phenyl-9-[4-(5-phenyl-1,3,4-oxadiazol-2-yl]methyl]

[0112] -9H-carbazole (abbreviation: CO11II) and 4-phenyl Nyl-4'-(9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation PCBA1BP) and bis{2-(4-fluorophenyl)-3,5-dimethylpyrazine {Nato}(picolinato)iridium(III) (abbreviation: Ir(dmFppr)2pic) and The third layer was formed to a thickness of 40 nm by co-evaporation of CO11II and The weight ratio of PCBA1BP to Ir(dmFppr)2pic was 1:0.15:0.1 = (CO11II:PCBA1BP:Ir(dmFppr)2pic) The rate was adjusted.

[0310] Thereafter, in the same manner as in the comparative light-emitting element 1, a fourth layer serving as an electron transport layer and a fifth layer serving as an electron injection layer were formed. A layer and a second electrode were formed to fabricate light-emitting elements 8 to 10.

[0311] In addition, the light-emitting elements 8 to 10 are made of a material other than the first layer 1511 and the second layer 1512. They are made in the same process.

[0312] The light-emitting devices 8 to 10 obtained as described above were placed in a glove box with a nitrogen atmosphere. After sealing the light emitting elements so that they are not exposed to the atmosphere, The operating characteristics of the device were measured. The measurements were carried out at room temperature (an atmosphere maintained at 25°C). Ta.

[0313] The current density-luminance characteristics of the light-emitting elements 8 to 10 are shown in FIG. The luminance vs. current efficiency characteristics are shown in Figure 35 and Figure 36, respectively. d / m 2 ), and the horizontal axis is the current density (mA / cm 2 ) and in Figure 35, the vertical axis shows luminance (cd / m 2), and the horizontal axis shows voltage (V). In Figure 36, the vertical axis shows current efficiency (cd / A) and the horizontal axis shows brightness. (cd / m 2 ) and 1000cd / m 2 The voltage, chromaticity, and The current efficiency and external quantum efficiency are shown in Table 5.

[0314] [Table 5]

[0315] Although high luminous efficiency was obtained from all the elements, comparing Light-emitting element 8 and Light-emitting element 9 It was found that the light-emitting device 9, which uses BPAFLP for the hole transport layer, has a higher current efficiency. Furthermore, when comparing the light-emitting element 9 with the light-emitting element 10, the hole injection layer and the hole transport layer In both cases, it was found that the current efficiency of the light-emitting element 10 using BPAFLP was higher.

[0316] Furthermore, for the light-emitting elements 8 to 10, the initial luminance was set to 1000 cd / cm 2 As low The results of a continuous lighting test using current drive are shown in Figure 37 (the vertical axis is 1000 cd / cm 2 The results of FIG. 37 show that the light-emitting element 8 was Even after 500 hours, the light-emitting element 9 maintained 64% of its initial brightness. The luminance of the light-emitting element 10 was 71% of the initial luminance even after 500 hours. Therefore, when BPAFLP (abbreviation) according to one embodiment of the present invention was applied, It was found that a light-emitting element with a long life can be obtained by using this method. [Example]

[0317] Here, the fluorene derivative according to one embodiment of the present invention is suitable as a hole transport material. Simulation results suggesting this are shown below.

[0318] The structural formulas of the organic compounds used in the simulation are shown below.

[0319] [ka]

[0320] First, structural formula (101) (abbreviation: BPAFLP), structural formula (109), structural formula (114) ), (Structural formula 151) (abbreviation: BPAFLBi), structural formula (164) and NPB singlet The most stable structures in the triplet and triplet states were calculated using density functional theory. The chemical calculation program is Gaussian03. The basis functions are H, C, and N atoms. , 6-311G(d,p) was used. The functional used was B3LYP.

[0321] Next, using the most stable structures of the singlet and triplet states obtained by the above calculations, Using the density functional theory, structural formula (101) (abbreviation: BPAFLP), structural formula (109), Structural formula (114), structural formula (151) (abbreviation: BPAFLBi), structural formula (164), and The excitation energies of NPB were calculated using the same basis functions and functionals as above.

[0322] The highest occupied molecular orbital (High Occ) of the most stable structure of the singlet state obtained by the calculation above The energy level of the Homotropic Molecular Orbital (HOMO) is The results are shown in Table 6.

[0323] [Table 6]

[0324] From the results in Table 6, the fluorene derivatives have a higher HOMO energy level than NPB. Therefore, when the above fluorene derivative is used as a hole transport material, Compared to NPB, it has been found to have superior hole injection properties to the light-emitting layer with a deeper HOMO. Ta.

[0325] In addition, the first excitation energy (1) of the most stable structure of the singlet state obtained by TDDFT calculation The results for the doublets are shown in Table 7.

[0326] [Table 7]

[0327] From the results in Table 7, when the above fluorene derivatives were used as hole transport materials, the In comparison, it is difficult for singlet excitons to escape to the hole transport layer at the boundary between the light emitting layer and the hole transport layer. I found out.

[0328] Next, the first excitation energy of the most stable triplet state obtained by TDDFT calculation (triplet The results for the items are shown in Table 8.

[0329] [Table 8]

[0330] From the results in Table 8, it can be seen that the above fluorene derivatives have a higher conductivity than NPB when used as hole transport materials. In contrast, triplet excitons escape from the light-emitting layer to the hole-transporting layer at the boundary between the light-emitting layer and the hole-transporting layer. Furthermore, when the above fluorene derivatives were used as phosphorescent host materials, It was found that the guest material is easily excited. [Example]

[0331] In this Example 9, the fluorene derivative 4-phenyl-4'-( 9-phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP) The fabrication method of the light-emitting element formed by the above process and the measurement results of the element characteristics are shown below.

[0332] The element structures of the light-emitting element 11 and the comparative light-emitting element 12 in Example 9 are shown in FIG. The light-emitting element 11 has a structure shown in FIG. 1, and the hole injection layer and the hole transport layer are made of the above-described fullerene of the present invention. It was formed using an oleic acid derivative.

[0333] First, on the substrate 1501, which is a glass substrate, indium oxide-tin oxide containing silicon oxide is formed. The first electrode 1502 was formed by sputtering. The thickness was set to 0 nm and the electrode area was set to 2 mm x 2 mm.

[0334] Next, an EL layer 1503 in which a plurality of layers are stacked is formed on the first electrode 1502. In the example, the EL layer 1503 comprises a first layer 1511 which is a hole injection layer, a second layer 1512 which is a hole transport layer, and a third layer 1513 which is a hole transport layer. The second layer 1512 is a light-emitting layer, the third layer 1513 is a light-emitting layer, and the fourth layer 1514 is an electron transport layer. 4 and a fifth layer 1515, which is an electron injection layer, are laminated in this order.

[0335] The first electrode 1502 is formed so that the surface on which the first electrode 1502 is formed faces downward. The substrate was fixed to a substrate holder installed in a vacuum deposition apparatus, and -4 Reduced to about Pa After pressing, a hole injection material was formed on the first electrode 1502 to a thickness of 50 nm. In the case of forming the light-emitting element 11, the first layer 1511, which is a hole injection layer, was formed. -phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: The hole injection layer was formed by co-evaporating BPAFLP and molybdenum(VI) oxide. A first layer 1511 was formed. Its thickness was set to 50 nm and it was made of BPAFLP and molybdenum oxide. The ratio of (VI) was 4:2 (BPAFLP:molybdenum oxide) by weight. In addition, when forming the comparative light-emitting element 12, the deposition rate was adjusted. '-Tris(carbazol-9-yl)triphenylamine (abbreviation: TCTA) and oxidation model The first layer 1511, which is a hole injection layer, is formed by co-evaporating bismuth (VI) and bismuth (VI). The film thickness was 50 nm, and the weight ratio of TCTA to molybdenum (VI) oxide was The deposition rate was adjusted to 4:2 (TCTA:molybdenum oxide).

[0336] Next, a hole transporting material is deposited on the first layer 1511 by a vapor deposition method using resistance heating. The second layer 1512 was formed as a hole transport layer. When forming the optical element 11, 4-phenyl-4'-(9-phenylfluorene-9- Comparative light-emitting element 12 was formed using phenyl)triphenylamine (abbreviation: BPAFLP). In this case, 4,4',4''-tris(carbazol-9-yl)triphenylamine ( Each was formed using TCTA.

[0337] Next, a third layer, which is a light-emitting layer, is formed on the second layer by a vapor deposition method using resistance heating. In this example, 9-[4-(4,5-diphenyl-4H-1,2,4-triazole] -3-yl)phenyl]-9H-carbazole (abbreviation: CzTAZI) and bis[2-(4 ',6'-difluorophenyl)pyridinato-N,C 2’ ]Iridium(III) picolinate The third layer was formed to a thickness of 30 nm by co-evaporation of FIrpic (abbreviation: FIrpic). Here, the weight ratio of CzTAZI to FIrpic was 1:0.06 = (CzTA The deposition rate was adjusted so that the SiO2 concentration was 1:1 (ZI:Frpic).

[0338] Furthermore, 3-(4-biphenylyl)-2-methyl-1,3-diphenyl-2-benzophenone (3-(4-biphenylyl)-2 ...))))))))))))))))))))))))))))))))))))))) )-4-phenyl-5-(4-tert-butylphenyl)-1,2,4-triazole (abbreviation: TAZ01) 10 nm, and on top of that, bathophenanthroline (abbreviation: BPhen) A fourth layer 1514 serving as an electron transporting layer was formed by depositing a film of SiO 2 to a thickness of 20 nm.

[0339] Thereafter, a fifth layer, which is an electron injection layer, and a second electrode are formed in the same manner as in the comparative light-emitting element 1. A light-emitting element 11 and a comparative light-emitting element 12 were fabricated.

[0340] The light-emitting element 11 and the comparative light-emitting element 12 have a first layer 1511 and a second layer 151 All but 2 are made using the same process.

[0341] The light-emitting element 11 and the comparative light-emitting element 12 obtained above were placed in a globe box in a nitrogen atmosphere. After sealing the light emitting elements in the box to prevent them from being exposed to the atmosphere, The operating characteristics of the light-emitting device were measured. I went there with a feeling of excitement.

[0342] FIG. 38 shows current density-luminance characteristics of the light-emitting element 11 and the comparative light-emitting element 12. The voltage-luminance characteristics are shown in Figure 39, and the luminance-current efficiency characteristics are shown in Figure 40. to luminance (cd / m 2 ), and the horizontal axis is the current density (mA / cm 2 ) and in Figure 39, the vertical axis indicates brightness. (cd / m 2 ), the horizontal axis shows voltage (V), and in Figure 40, the vertical axis shows current efficiency (cd / A), The horizontal axis shows the luminance (cd / m 2 ) and 1000cd / m 2 The power of the light-emitting element in the vicinity The voltage, chromaticity, current efficiency, and external quantum efficiency are shown in Table 9.

[0343] [Table 9]

[0344] BPAFLP (abbreviation), which is a fluorene derivative of the present invention, is applied to the first layer 1511 and the second layer 1512. The light-emitting element 11 used in the layer 1512 had a luminance of 910 cd / m when the driving voltage was 5.2 V. 2 The current value was 0.18mA. The comparative light-emitting element 12 used had a luminance of 850 cd / m when the driving voltage was 5.2 V. 2 , current value This indicates that the first layer 1511 and the second layer 1512 are made of BPA. The light-emitting element 11 using FLP (abbreviation) has higher current efficiency than the comparative light-emitting element 12. Therefore, it was found that BPAFLP (abbreviation) according to one embodiment of the present invention was used as a hole injection layer and By applying this to the hole transport layer, a highly efficient light emitting device can be obtained. Understood.

[0345] FIG. 41 shows emission spectra of the light-emitting element 11 and the comparative light-emitting element 12.

[0346] Both the light-emitting element 11 and the comparative light-emitting element 12 contain a phosphorescent dopant material, FIr The emission spectrum from pic (abbreviation) was observed, and the emission spectrum from the third layer 1513 and the adjacent layer No light emission was observed. This indicates that the carriers in the third layer 1513 were The recombination of the carriers was good, and light emission was possible with a good carrier balance. Since the light-emitting element 11 exhibits higher current efficiency than the comparative light-emitting element 12, FLP (abbreviation) has better carrier balance (blocking electrons from the third layer 1513) and triplet excitation energy (In this case, the BPAFLP (abbreviation) according to one embodiment of the present invention The LUMO level is almost the same as that of TCTA (abbreviation) (-2.30 eV), and the band The gap (Bg) is narrower than that of TCTA (abbreviation) (3.40 eV). Since BPAFLP (abbreviation) according to one embodiment of the present invention is a material with higher hole transport properties, light emission It is believed that the higher efficiency was achieved due to the efficient recombination of carriers in the layer. can be obtained.) [Example]

[0347] In this example, the fluorene derivative 4-phenyl-4'-(9 -phenylfluoren-9-yl)triphenylamine (abbreviation: BPAFLP) The fabrication method of the formed light-emitting element and the measurement results of the element characteristics are shown.

[0348] The element structure of the light-emitting element 13 in this example is the structure shown in FIG. 18, and hole injection The fluorene derivative (abbreviation: BPAFLP) of the present invention is used for the hole injection layer and the hole transport layer. The structural formula of the organic compound used in this example is shown below.

[0349] First, on the substrate 1501, which is a glass substrate, indium oxide-tin oxide containing silicon oxide is formed. The first electrode 1502 was formed by sputtering. The thickness was set to 10 nm and the electrode area was set to 2 mm x 2 mm.

[0350] Next, an EL layer 1503 in which a plurality of layers are stacked is formed on the first electrode 1502. In the example, the EL layer 1503 comprises a first layer 1511 which is a hole injection layer, a second layer 1512 which is a hole transport layer, and a third layer 1513 which is a hole transport layer. The second layer 1512 is a light-emitting layer, the third layer 1513 is a light-emitting layer, and the fourth layer 1514 is an electron transport layer. 4 and a fifth layer 1515, which is an electron injection layer, are laminated in this order.

[0351] The first electrode 1502 is formed so that the surface on which the first electrode 1502 is formed faces downward. The substrate was fixed to a substrate holder installed in a vacuum deposition apparatus, and -4 Reduced to about Pa After pressing, a hole injection material was formed on the first electrode 1502 to a thickness of 50 nm. In the case of forming the light-emitting element 13, the first layer 1511, which is a hole injection layer, was formed. -phenyl-4'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: The hole injection layer was formed by co-evaporating BPAFLP and molybdenum(VI) oxide. A first layer 1511 was formed. Its thickness was set to 50 nm and it was made of BPAFLP and molybdenum oxide. The ratio of (VI) was 4:2 (BPAFLP:molybdenum oxide) by weight. The arrival rate was adjusted.

[0352] Next, a hole transporting material is deposited on the first layer 1511 by a vapor deposition method using resistance heating. The second layer 1512 was formed as a hole transport layer. When forming the optical element 13, 4-phenyl-4'-(9-phenylfluorene-9- The compound was formed using (phenyl)triphenylamine (abbreviation: BPAFLP).

[0353] Next, a third layer (a light-emitting layer) is formed on the second layer 1512 by a vapor deposition method using resistance heating. Formation of 1513: 4-[3-(triphenylen-2-yl)phenyl]dibenzothio Phen (abbreviation: mDBTPTp-II) and tris(2-phenylpyridinato-N,C 2’ ) iridium (III) (abbreviation: Ir(ppy)3), and the third The layer 1513 was formed to a thickness of 40 nm. The weight ratio of mDBTPTp-II to Ir(ppy)3 is 1:0.08 = (mDBTPTp-II:Ir(ppy)3). The deposition rate was adjusted so that

[0354] Furthermore, mDBTPTp-II was deposited on the third layer 1513 by using a vapor deposition method using resistance heating. 10 nm, and then bathophenanthroline (abbreviation: BPhen) is applied on top to a thickness of 20 nm. A fourth layer 1514 serving as an electron transporting layer was formed in this manner.

[0355] Thereafter, a fifth layer, which is an electron injection layer, and a second electrode are formed in the same manner as in the comparative light-emitting element 1. A light-emitting device 13 was fabricated.

[0356] The light-emitting device 13 obtained as described above was placed in a glove box with a nitrogen atmosphere. After sealing the element 13 so that it is not exposed to the atmosphere, the operating characteristics of the light emitting element 13 are The measurements were carried out at room temperature (in an atmosphere maintained at 25°C).

[0357] The current density-luminance characteristics of the light-emitting element 13 are shown in FIG. 42. The voltage-luminance characteristics are shown in FIG. 43. The luminance-current efficiency characteristics are shown in Figure 44. In Figure 42, the vertical axis shows the luminance (cd / m 2 ), The horizontal axis shows the current density (mA / cm 2 ) and in Figure 43, the vertical axis shows the luminance (cd / m 2 ), on the horizontal axis In Figure 44, the vertical axis represents the current efficiency (cd / A) and the horizontal axis represents the luminance (cd / m 2 ) and 1000cd / m 2 The voltage, chromaticity, and current efficiency of the light-emitting element in the vicinity Shown in Figure 7.

[0358] [Table 10]

[0359] In this example, a fluorene derivative (abbreviation: BPAFLP) of the present invention was used to form a It was confirmed that the light-emitting element 13 obtained the characteristics required for a light-emitting element and functioned satisfactorily. The results of reliability tests have shown that even when the light-emitting element is continuously lit, there is no degradation due to defects in the film. It was found that a highly reliable light-emitting element was obtained without the occurrence of short circuits.

[0360] Regarding the light-emitting element 13, the initial luminance is set to 1000 cd / cm 2 As a result, low current drive The results showed that the light-emitting element 13 maintained the initial luminance even after 1900 hours. The brightness was maintained at 86%, demonstrating a long life. By applying BPAFLP (abbreviation) as a hole transport layer, a long-life light-emitting device can be realized. I found that I could get it. [Example]

[0361] <Synthesis Example 3> In this example, a full-formula compound, which is one embodiment of the present invention shown in Embodiment 1 as general formula (G1), was used. A synthesis example of a diol derivative is shown below. Specifically, the 4-diol derivative shown in the structural formula (118) of the first embodiment is -phenyl-3'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: The synthesis method of mBPAFLP is explained below. The structure of mBPAFLP is shown below.

[0362] [ka]

[0363] [Step 1: Synthesis of 9-(3-bromophenyl)-9-phenylfluorene] In a 200 mL three-neck flask, add 4.2 g (18 mmol) of 2-bromobiphenyl and dehydrate 30 mL of HF solution was added and stirred at -78°C. 11 mL (18 mmol) of the hexane solution was added dropwise and stirred for 2.5 hours. Add 40 mL of a solution of 3.9 g (15 mmol) of bromobenzophenone in dehydrated THF dropwise, and After stirring for 1 hour, the mixture was stirred at room temperature for 16 hours.

[0364] After the reaction, 1N aqueous hydrochloric acid was added to the mixture and stirred for 1 hour. The resulting organic phase was concentrated to give a candy-like substance.

[0365] In a 200 mL eggplant flask, add this syrup, 20 mL of glacial acetic acid, and 1.0 mL of hydrochloric acid. The mixture was heated and stirred at 130°C for 2 hours under a nitrogen atmosphere to allow the reaction to proceed.

[0366] After the reaction, the reaction mixture was added dropwise to 150 mL of ice-cold water. The supernatant was removed by decantation. The caramel-like solid was dissolved in 1 mL of toluene. Dissolve in 00 mL of saturated sodium bicarbonate solution and add while stirring until no more bubbles form. After washing the organic layer with water, silica gel was added to adsorb the water. The filtrate obtained by filtering the mixture was concentrated, and methanol was added. The mixture was then cooled on ice and subjected to ultrasonic waves. The resulting solid was collected by filtration. The target product, a white powder, was obtained in an amount of 4.9 g and a yield of 83%. The reaction scheme of the synthesis method is shown below in (J-5).

[0367] [ka]

[0368] [Step 2: 4-phenyl-3'-(9-phenylfluoren-9-yl)triphenyl Synthesis of mBPAFLP In a 200 mL three-neck flask, add 9-(3-bromophenyl)-9-phenylfluorene. 2.4 g (6.0 mmol), 4-phenyl-diphenylamine 1.5 g (6.0 mmol) ol), sodium tert-butoxide 1.0g (10mmol), bis(dibenzoyl) Add 3.0 mg (0.005 mmol) of diphenyldiphenylacetone palladium(0) to the flask. The atmosphere inside the container was replaced with nitrogen. 25 mL of dehydrated xylene was added to this mixture. The mixture was degassed under reduced pressure with stirring, and then tri(tert-butyl)phosphine (10w 0.2 mL (0.1 mmol) of a hexane solution (t% hexane solution) was added. The mixture was then cooled under a nitrogen atmosphere. The mixture was heated and stirred at 130°C for 2.5 hours to react.

[0369] After the reaction, 200 mL of toluene was added to the reaction mixture, and the suspension was Lumina, Celite (Wako Pure Chemical Industries, Ltd., Catalog No.: 531-16855) The filtrate was concentrated and purified by silica gel column chromatography (developing solvent The resulting fraction was concentrated and purified with toluene:hexane (1:4). After adding acetone and methanol and applying ultrasonic waves, the desired white powder was obtained by recrystallization. The compound was obtained in an amount of 3.2 g and a yield of 97%. The reaction scheme of the above synthesis method is shown below in (J-6). Shown below.

[0370] [ka]

[0371] Rf values ​​in silica gel thin layer chromatography (TLC) (eluent: ethyl acetate:hexane) The target compound was 0.5, 1, 9-(3-bromophenyl)-9-phenyl. The values ​​for difluorene were 0.62 and 4-phenyl-diphenylamine were 0.39.

[0372] The compound obtained in step 2 above was measured by nuclear magnetic resonance (NMR). The constant data is shown. 1 The 1 H NMR chart is shown in Figure 45. From the measurement results, it is clear that the above structure The fluorene derivative of the present invention, mBPAFLP (abbreviation), represented by the formula (118) was obtained. It was found that

[0373] 1 H NMR (CDCl3,300MHz): δ(ppm)=6.72(d, J=8. 4, 1H), 6.92-7.36(m, 22H), 7.40-7.44(m, 4H), 7 .54-7.57(m, 2H), 7.72-7.75(m, 2H).

[0374] The molecular weight of the compound obtained in step 2 was measured using a GC / MS detector (Thermo Measurements were performed using a Fisher ITQ1100 ion trap GCMS system. This resulted in the detection of a main peak with a molecular weight of 561.3 (mode EI+), and the target It was confirmed that the product mBPAFLP (abbreviation) was obtained.

[0375] In addition, various physical properties of the obtained target substance, mBPAFLP (abbreviation), were measured as follows. It was determined.

[0376] The absorption spectrum (measurement range 200 nm to 800 nm) was measured using a UV-visible spectrophotometer (Japan The absorption spectra of the toluene solution and thin film are shown in Figure 46. The horizontal axis represents wavelength (nm) and the vertical axis represents absorption intensity (arbitrary units). The liquid was measured in a quartz cell, and the absorption spectrum of quartz and toluene was subtracted. The absorption spectrum of the thin film was measured by depositing it on a quartz substrate. The spectra from which the absorption peak on the long wavelength side was subtracted are shown. In the case of the toluene solution, the peaks are observed around 310 nm and 325 nm, while in the case of the thin film, the peaks are observed around 31 It was found to be found around 2 nm and 329 nm.

[0377] The emission spectrum was measured using a fluorometer (FS920 manufactured by Hamamatsu Photonics Co., Ltd.). Figure 47 shows the emission spectra of the toluene solution and thin film. The horizontal axis is wavelength (nm) and the vertical axis is represents the emission intensity (arbitrary unit). The toluene solution was measured in a quartz cell, and the thin film was measured in a quartz cell. The sample deposited on the substrate was measured. From these spectra, the maximum emission wavelength was For solutions, the excitation wavelength is 382 nm (excitation wavelength 340 nm), and for thin films, the excitation wavelength is 393 nm (excitation wavelength It was found that the wavelength was 343 nm.

[0378] The thin film was measured in air by photoelectron spectroscopy (Riken Keiki, AC-2). The absorption edge was -5.73 eV. From the Tauc plot of the absorption spectrum of the thin film, Therefore, the energy gap in the solid state is estimated to be 3.34 eV. This means that the LUMO level is -2.39 eV. mBPAFLP (abbreviation) has a relatively deep HOMO level and a wide band gap (B g).

[0379] The redox reaction characteristics were investigated by cyclic voltammetry (CV) measurements. The electrochemical analyzer (manufactured by BAS Co., Ltd., model number: ALS model 600A) or 600C) was used.

[0380] The oxidation reaction characteristics were measured by running the potential of the working electrode relative to the reference electrode from 0.38 V to 0.69 V. After the voltage was measured, the potential was scanned from 0.69 V to 0.38 V. As a result, the HOMO level was The oxidation peak was found to be -5.53 eV. This indicates that the oxidized and neutral states are repetitively oxidized and reduced. It was found to show sexuality.

[0381] The melting point was also measured and was found to be 211-212°C. [Example]

[0382] In this example, the fluorene derivative 4-phenyl-3'-(9 -phenylfluoren-9-yl)triphenylamine (abbreviation: mBPAFLP) The fabrication method of the light-emitting element formed by the above process and the measurement results of the element characteristics are shown below.

[0383] The element structure of the light-emitting element in this example is the structure shown in FIG. 4 is a compound in which the fluorene derivative ( It was formed using mBPAFLP (abbreviation: mBPAFLP).

[0384] First, on the substrate 1501, which is a glass substrate, indium oxide-tin oxide containing silicon oxide is formed. The first electrode 1502 was formed by sputtering. The thickness was set to 10 nm and the electrode area was set to 2 mm x 2 mm.

[0385] Next, an EL layer 1503 in which a plurality of layers are stacked is formed on the first electrode 1502. In Example 5, the EL layer 1503 includes a first layer 1511 which is a hole injection layer, a second layer 1512 which is a hole transport layer, and a third layer 1513 which is a hole transport layer. a second layer 1512 which is a light-emitting layer, a third layer 1513 which is a light-emitting layer, and a fourth layer 1514 which is an electron transport layer. 14 and a fifth layer 1515 which is an electron injection layer are laminated in this order.

[0386] The first electrode 1502 is formed so that the surface on which the first electrode 1502 is formed faces downward. The substrate was fixed to a substrate holder installed in a vacuum deposition apparatus, and -4 Reduced to about Pa After pressing, a hole injection material was formed on the first electrode 1502 to a thickness of 50 nm. In the case of forming the light-emitting element 14, the first layer 1511, which is a hole injection layer, was formed. -phenyl-3'-(9-phenylfluoren-9-yl)triphenylamine (abbreviation: The hole injection layer was formed by co-evaporating mBPAFLP and molybdenum(VI) oxide. The first layer 1511 was formed with a thickness of 50 nm, and consisted of mBPAFLP (abbreviation) and acid. The weight ratio of molybdenum(VI) oxide to mBPAFLP is 4:2 = (mBPAFLP:molybdenum oxide) The deposition rate was adjusted so that: 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NP B) and molybdenum (VI) oxide were co-deposited to form the first layer 1, which is a hole injection layer. The film thickness was 50 nm, and the ratio of NPB to molybdenum (VI) oxide was The deposition rate was adjusted so that the weight ratio was 4:2 (NPB:molybdenum oxide).

[0387] Next, a hole transporting material is deposited on the first layer 1511 by a vapor deposition method using resistance heating. The second layer 1512 was formed as a hole transport layer. When forming the optical element 14, 4-phenyl-3'-(9-phenylfluorene-9- Comparative light-emitting element 15 was formed using mBPAFLP. In this case, 4,4'-bis[N-(1-naphthyl)-N-phenylamino]biphenyl (abbreviation: NPB) were used to form the respective films.

[0388] Next, a third layer (a light-emitting layer) is formed on the second layer 1512 by a vapor deposition method using resistance heating. Formation of 1513: 9-[4-(10-phenyl-9-anthryl)phenyl]-9H -carbazole (abbreviation: CzPA) and 4-(10-phenyl-9-anthryl)-4'- (9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBA The third layer 1513 was formed to a thickness of 30 nm by co-evaporation of SiO 2 and PA. The weight ratio of CzPA to PCBAPA was 1:0.075=(CzPA:PCBAPA) The deposition rate was adjusted so that

[0389] Furthermore, tris(8-quinolinol) was deposited on the third layer 1513 by using a vapor deposition method using resistance heating. A 10 nm layer of (tetrahydro)aluminum(III) (abbreviation: Alq) was deposited on it, and bathophenanthro Phosphorus (abbreviation: BPhen) was formed to a thickness of 20 nm, and the fourth electron transport layer was formed. A layer 1514 was formed.

[0390] On the fourth layer 1514, a lithium fluoride (LiF) film is formed to a thickness of 1 nm. In this way, a fifth layer 1515 serving as an electron injection layer was formed.

[0391] Finally, aluminum was evaporated to a thickness of 200 nm using resistance heating. The second electrode 1504 is formed by film deposition, and the light-emitting element 14 and the comparative light-emitting element 15 are formed. It was made.

[0392] The light-emitting element 14 and the comparative light-emitting element 15 have a first layer 1511 and a second layer 15 All but 12 are made using the same process.

[0393] The light-emitting element 14 and the comparative light-emitting element 15 obtained above were placed in a globe box in a nitrogen atmosphere. After sealing the light emitting elements in the box to prevent them from being exposed to the atmosphere, The operating characteristics of the light-emitting device were measured. I went there with a feeling of excitement.

[0394] FIG. 48 shows current density-luminance characteristics of the light-emitting element 14 and the comparative light-emitting element 15. The voltage-luminance characteristics are shown in Figure 49, and the luminance-current efficiency characteristics are shown in Figure 50. to luminance (cd / m 2 ), and the horizontal axis is the current density (mA / cm 2 ) and in Figure 49, the vertical axis indicates brightness. (cd / m 2 ), the horizontal axis shows voltage (V), and in Figure 50, the vertical axis shows current efficiency (cd / A), The horizontal axis shows the luminance (cd / m 2 ) and 1000cd / cm 2 of light-emitting elements in the vicinity The voltage, chromaticity, and current efficiency are shown in Table 11.

[0395] [Table 11]

[0396] The light-emitting element 14 has a luminance of 1100 cd / m when the driving voltage is 3.4 V. 2 , the current value is 0. The current consumption was 72 mA. The light-emitting element 14 using BPAFLP (abbreviation) for the second layer 1512 has high current efficiency. This is because the carrier balance of the light-emitting element 14 is lower than that of the comparative light-emitting element 15. This is thought to be due to the improvement of BPAFLP (abbreviation) (compared to NPB). The HOMO level is close to that of CzPA (abbreviation), the host material of the light-emitting layer, so This is thought to be due to the improved hole injection from the hole transport layer to the light emitting layer. Because the LUMO level of BPAFLP (abbreviation) is higher than that of BPAFLP, hole transport from the emitting layer This is thought to be due to the improved electron blocking properties of the layer. Because the band gap (Bg) of BPAFLP (abbreviation) is wide, the third layer 1513 (light emitting layer) to the adjacent second layer 1512 (without being quenched). )This is thought to be due to the fact that they were confined.

[0397] Furthermore, for the light-emitting element 14 and the comparative light-emitting element 15, the initial luminance was 1000 cd / cm 2 The test was conducted with low current drive and continuous lighting was performed with the current set to 100%. The light-emitting element 14 maintained 80% of the initial luminance, and the comparative light-emitting element 15 maintained 72% of the initial luminance. Therefore, it was found that the mBPAFLP (abbreviation) of the present invention is suitable for It was found that a light-emitting element with a long life can be obtained by using this.

[0398] (Reference example 1) The 4-(10-phenyl-9-anthryl)-4'-( 9-phenyl-9H-carbazol-3-yl)triphenylamine (abbreviation: PCBAP) The synthesis method of A) will be specifically explained.

[0399] [ka]

[0400] 4-(10-phenyl-9-anthryl)-4'-(9-phenyl-9H-carbazole) Synthesis of PCBAPA The scheme is shown below (X-1).

[0401] [ka]

[0402] 9-(4-bromophenyl)-10-phenylanthracene 7.8g (12mmol) , 4-(9-phenyl-9H-carbazol-3-yl)diphenylamine (abbreviation: PC BA) 4.8 g (12 mmol), sodium tert-butoxide 5.2 g (52 m mol) was placed in a 300 mL three-neck flask, and the atmosphere in the flask was replaced with nitrogen. 60 mL of toluene, 0 mL of tri(tert-butyl)phosphine (10 wt% hexane solution) The mixture was degassed under reduced pressure with stirring. After degassing, bis(dibenzyl) 136 mg (0.24 mmol) of (phenylideneacetone)palladium(0) was added to this. The mixture was stirred at 100°C for 3 hours. After stirring, about 50 mL of toluene was added to the mixture. Celite (Wako Pure Chemical Industries, Ltd., Catalog No.: 531-16855), alumina , through Florisil (Wako Pure Chemical Industries, Ltd., catalog number: 540-00135) The resulting filtrate was concentrated to give a yellow solid. The solution was recrystallized at 100°C for 1 hour to obtain 6.6 g of a pale yellow solid of PCBAPA, the target product, in a yield of 75%.

[0403] The resulting pale yellow powdery solid (3.0 g) was purified by train sublimation. The sublimation purification conditions were a pressure of 8.7 Pa and argon gas flow rate of 3.0 mL / min. Then, PCBAPA was heated at 350°C. After purification by sublimation, the pale yellow solid PCBAPA was obtained. 7g was obtained with a recovery rate of 90%.

[0404] The resulting compound was analyzed by nuclear magnetic resonance ( 1 The measurement data is shown below. show.

[0405] 1 H NMR(CDCl3,300MHz):δ=7.09-7.14(m,1H), 7.28-7.72(m,33H),7.88(d,J=8.4Hz,2H),8.19 (d,J=7.2Hz,1H),8.37(d,J=1.5Hz,1H).

[0406] The measurement results showed that 4-(10-phenyl-9-anthryl)-4'-(9-phenyl-9 H-carbazol-3-yl)triphenylamine (abbreviation: PCBAPA) was obtained. I found out that...

[0407] The above-mentioned 4-(10-phenyl-9-anthryl)-4'-(9-phenyl-9H-chlor) By using PCBAPA, Light-emitting elements 1 to 5 shown in the examples can be formed.

[0408] (Reference example 2) The 3-phenyl-9-[4-(5-phenyl-1,3 ,4-oxadiazol-2-yl)phenyl]-9H-carbazole (abbreviation: CO11 The synthesis method II) will be specifically explained.

[0409] [ka]

[0410] 3-phenyl-9-[4-(5-phenyl-1,3,4-oxadiazol-2-yl] The synthesis scheme of 9H-phenyl-9H-carbazole (abbreviation: CO11II) is shown in (Y-1). Shown below.

[0411] [ka]

[0412] 2-(4-iodophenyl)-5-phenyl-1,3,4-oxadiazole 2.3g (6.6 mmol), 3-phenyl-9H-carbazole 1.6 g (6.6 mmol), 1.4 g (15 mmol) of sodium tert-butoxide was placed in a 100 mL three-neck flask. The mixture was poured into a flask and the inside of the flask was replaced with nitrogen. Add 0.2 mL of a 10% hexane solution of t-butylphosphine and heat the flask. The mixture was degassed by reducing the pressure with a spirator, and the atmosphere in the flask was replaced with nitrogen. To this mixture was added 0.058 g (0. 10 mmol) was added and stirred at 80°C for 15 hours under a nitrogen stream. Toluene was added, and the suspension was washed with saturated aqueous sodium carbonate solution and saturated brine in that order. After washing, magnesium sulfate was added to the organic layer to absorb water. The filtrate was filtered through a filter and filtered over Celite (Wako Pure Chemical Industries, Ltd., catalog number The filtrate was filtered through a filter (540-16855) and the filtrate was concentrated to give The compound was purified by silica gel column chromatography. First, toluene was used as the developing solvent, and then a mixed solvent of toluene:ethyl acetate = 4:1 was used. The resulting fraction was concentrated to give a solid. Acetone was added to the mixture, and the mixture was washed by ultrasonic irradiation. The mixture was suction filtered to recover the solid. The recovered solid was recrystallized in a mixed solvent of chloroform and hexane, resulting in a powdery white The solid was obtained in an amount of 2.0 g and a yield of 64%.

[0413] The resulting white solid (1.1 g) was purified by train sublimation. The purification was carried out at 240°C for 16 hours under a reduced pressure of 3.0 Pa with an argon flow rate of 5 mL / min. The yield was 0.98 g, which was 89%.

[0414] The obtained compound was measured by nuclear magnetic resonance (1H NMR). The measurement data are as follows: show.

[0415] 1 H NMR(CDCl3,300MHz):δ=7.30-7.76(m,13H) , 7.79(d,J=8.3Hz,2H), 8.14-8.24(m,3H), 8.35 (sd,J=1.5Hz,1H), 8.39(d,J=8.8Hz,2H).

[0416] The measurement results showed that 3-phenyl-9-[4-(5-phenyl-1,3,4-oxadiazo (2-yl)phenyl]-9H-carbazole (abbreviation: CO11II) was obtained. You can see that.

[0417] The above-mentioned 3-phenyl-9-[4-(5-phenyl-1,3,4-oxadiazole-2 -yl)phenyl]-9H-carbazole (abbreviation: CO11II) The light-emitting elements 6 to 10 shown in the examples can be formed.

[0418] (Reference example 3) 4-phenyl-4'-(9-phenyl-9H-carbazole-3 -yl)triphenylamine (abbreviation: PCBA1BP) synthesis method do.

[0419] [ka]

[0420] 4-phenyl-4'-(9-phenyl-9H-carbazol-3-yl)triphenyl The synthesis scheme of the amine (abbreviation: PCBA1BP) is shown in (Z-1).

[0421] [ka]

[0422] 4-(9-phenyl-9H-carbazol-3-yl)diphenylamine 2.0g (4 0.9mmol), 4-bromobiphenyl 1.1g (4.9mmol), sodium te Place 2.0 g (20 mmol) of rt-butoxide into a 100 mL three-neck flask. The atmosphere was replaced with nitrogen. To this mixture, 50 mL of toluene and tri(tert-butyl)phosphine were added. 0.30 mL of vin (10 wt % hexane solution) was added.

[0423] This mixture was degassed under reduced pressure while stirring, and after degassing, bis(dibenzylideneacetone) 0.10 g of palladium(0) was added. Then, the mixture was heated and stirred at 80° C. for 5 hours. After the reaction, toluene was added to the reaction mixture, and the resulting suspension was placed in a ceramic bath. Ito (Wako Pure Chemical Industries, Ltd., Catalog No.: 531-16855), alumina, fluorine Suction filtration through Zeal (Wako Pure Chemical Industries, Ltd., catalog number: 540-00135) The filtrate was washed with saturated aqueous sodium carbonate and saturated saline in this order. Magnesium sulfate was added to the organic layer to absorb water. After drying, the mixture was suction filtered. The magnesium sulfate was removed to obtain a filtrate.

[0424] The obtained filtrate was concentrated and purified by silica gel column chromatography. Silica gel column chromatography is first developed using a mixed solvent of toluene:hexane = 1:9. A mixture of toluene and hexane (3:7) is used as the developing solvent. The obtained fraction was concentrated, and the solid was extracted with chloroform and hexane. The yield of the white powdery solid was 2.3 g, and the yield was 84%. there were.

[0425] The resulting white solid (1.2 g) was purified by train sublimation. The purification was carried out at 280°C for 20 hours under a reduced pressure of 7.0 Pa with an argon flow rate of 3 mL / min. The yield was 1.1 g, or 89%.

[0426] The resulting compound was analyzed by nuclear magnetic resonance ( 1 The measurement data is shown below. show.

[0427] 1 H NMR(DMSO-d6,300MHz):δ(ppm)=7.05-7.20 (m,7H),7.28-7.78(m,21H),8.34(d,J=7.8Hz,1 H), 8.57(s,1H)

[0428] The measurement results showed that 4-phenyl-4'-(9-phenyl-9H-carbazol-3-yl ) triphenylamine (abbreviation: PCBA1BP) was obtained.

[0429] The above-mentioned 4-phenyl-4'-(9-phenyl-9H-carbazol-3-yl)triflate By using phenylamine (abbreviation: PCBA1BP), the light-emitting element 8 shown in the previous example can be obtained. The light emitting element 10 can be formed.

[0430] (Reference example 4) 4-phenyl-4'-(9-phenyl-9H-carbazole-3- Another synthesis method for PCBA1BP is specifically explained. This synthesis method is preferable because it is simple and produces the target product in high yield with high purity.

[0431] [ka]

[0432] Step 1: Synthesis of 3-(4-bromophenyl)-9-phenyl-9H-carbazole Law] The synthesis scheme of 3-(4-bromophenyl)-9-phenyl-9H-carbazole (Z -2).

[0433] [ka]

[0434] In a 300 mL three-neck flask, 14 g (50 mmol) of 4-bromoiodobenzene and 9 -phenyl-9H-carbazole-3-boronic acid 14g (50mmol), palladium acetate 110 mg (0.5 mmol) of ammonium phosphate (II), 300 mg ( 1.0 mmol), toluene 50 mL, ethanol 10 mL, 2 mol / L potassium carbonate A mixture of 25 mL of aqueous solution was degassed under reduced pressure while stirring, and then heated at 80°C under a nitrogen atmosphere. The mixture was heated and stirred for 6 hours to react.

[0435] After the reaction, 200 mL of toluene was added to the reaction mixture, and the suspension was Wako Pure Chemical Industries, Ltd., Catalog No.: 540-00135), Celite (Wako Pure Chemical Industries, Ltd. The resulting filtrate was washed with water. The suspension was washed, and magnesium sulfate was added to absorb the water. The suspension was filtered to obtain a filtrate. The obtained filtrate was concentrated and purified by silica gel column chromatography. When using a mixed solvent of toluene and hexane (toluene The obtained fraction was concentrated, hexane was added, and the mixture was subjected to ultrasonic After washing, the mixture was recrystallized to obtain 15 g of the desired white powder in 75% yield. .

[0436] Rf values ​​in silica gel thin layer chromatography (TLC) (eluent: ethyl acetate:hexane) The HCl concentration of the target compound was 0.32, and that of 4-bromoiodobenzene was 0.74. .

[0437] In addition, the by-product, 1,4-bis(9-phenyl-9H-carbazol-3-yl)benzyl The Rf value of benzene (developing solvent ethyl acetate:hexane = 1:10) was 0.23, but Only a faint spot was observed on TLC in the reaction suspension. The dihalide 4-bromoiodobenzene used in the experiment had the iodine moiety replaced by bromine. Because it is more reactive than the 9-phenyl moiety, it is selectively (preferentially) converted to the boron compound -9H-carbazole-3-boronic acid (i.e., dihalogenation The compound reacted with the boron compound in a ratio of approximately 1:1. Since the Rf value of the product is sufficiently different, the target product and by-products can be separated in the column purification described above. The items could be easily separated.

[0438] The compound obtained in step 1 above was measured by nuclear magnetic resonance (NMR). The constant data is shown.

[0439] 1 H NMR(CDCl3,300MHz):δ(ppm)=7.24-7.32(m ,1H), 7.40-7.64(m,13H), 8.17(d,J=7.2,1H), 8 .29(s,1H).

[0440] The measurement results showed that the target substance, 3-(4-bromophenyl)-9-phenyl-9H-carbamate, It was confirmed that bazol was obtained.

[0441] The molecular weight of the above compound was measured using a GC-MS detector (Thermo Fisher, ITQ1 The molecular weight was measured using a GCMS system with a molecular weight of 397.13 (Mo. The main peak was detected as EI+, and the measurement results identified the target compound, 3-(4-bromo-3-methyl-2-phenyl-2-propanol). It was confirmed that (bromophenyl)-9-phenyl-9H-carbazole was obtained.

[0442] In addition, this GC-MS detection also revealed the by-product 1,4-bis(9-phenyl-9H-carboxylate). No peaks derived from (rubazol-3-yl)benzene (molecular weight 560.2) were detected. Therefore, by carrying out the reaction in step 1, the target product can be obtained easily and with high purity in a very high yield. You can see what you've gained.

[0443] [Step 2: 4-phenyl-4'-(9-phenyl-9H-carbazol-3-yl) Synthesis of triphenylamine (abbreviated as PCBA1BP) 4-phenyl-4'-(9-phenyl-9H-carbazol-3-yl)triphenyla The synthesis scheme of PCBA1BP is shown in (Z-3).

[0444] [ka] 4-Phenyl-diphenylamine and 3-(4-bromophenyl)-9-phenyl-9 H-carbazole using a palladium catalyst, a ligand for the palladium catalyst, and a base, The mixture was heated and stirred in an organic solvent to cause a reaction.

[0445] After the reaction, the reaction mixture was purified to obtain the target product as a white powder.

[0446] The resulting compound was analyzed by nuclear magnetic resonance ( 1 1 H NMR). As in Example 3, the target compound, 4-phenyl-4'-(9-phenyl-9H-carbazole-3 It was found that the compound obtained was (-yl)triphenylamine (abbreviation: PCBA1BP).

[0447] From the above, the synthesis method shown in Reference Example 4 can easily obtain the target product with high purity and good yield. It was found that... [Explanation of symbols]

[0448] 101 Substrate 102 first electrode 103 EL layer 104 Second electrode 111 layers 112 layers 113 layers 114 layers 115 layers 301 Electrode 302 Electrode 303 EL layer 304 EL layer 305 Charge generation layer 401 Source side drive circuit 402 Pixel section 403 Gate side drive circuit 404 Sealing substrate 405 Sealing material 407 Space 408 Wiring 409 FPC (Flexible Printed Circuit) 410 Element substrate 411 Switching TFT 412 Current control TFT 413 First electrode 414 Insulators 416 EL layer 417 Second Electrode 418 Light-emitting element 423 N-channel TFT 424 P-channel TFT 501 PCB 502 first electrode 503 Second electrode 504 EL layer 505 Insulation Layer 506 Partition layer 511 First Light Emitting Unit 512 Second Light Emitting Unit 513 Charge generation layer 521 First electrode 522 Second electrode 611 Case 612 Support stand 613 Display section 614 Speaker section 615 Video input terminal 621 Main Unit 622 Case 623 Display section 624 keyboard 625 External connection port 626 Pointing Device 631 Main Unit 632 Case 633 Display section 634 Audio Input Unit 635 Audio output section 636 Operation Key 637 External connection port 638 Antenna 641 Main Unit 642 Display section 643 Case 644 external connection port 645 Remote control receiver 646 Image receiving unit 647 Battery 648 Audio Input Unit 649 Operation Key 650 Eyepiece 701 Case 702 Liquid crystal layer 703 Backlight 704 Case 705 Driver IC 706 terminal 801 Case 802 light source 901 Lighting equipment 902 Television equipment 913 layers 1501 Circuit Board 1502 First electrode 1503 EL layer 1504 Second electrode 1511 layers 1512 layers 1513 layers 1514 layers 1515 layers

Claims

[Claim 1] A fluorene derivative represented by general formula (G1): 【Chemistry 1】 (In the formula, R １ ~R ８ each independently represents a hydrogen atom, an alkyl group having 1 to 6 carbon atoms, a substituted or unsubstituted phenyl group, or a substituted or unsubstituted biphenyl group. １ ~α ４ each independently represents a substituted or unsubstituted arylene group having 6 to 12 carbon atoms. １ , Ar ２ each independently represents an aryl group having 6 to 13 carbon atoms forming a ring, Ar ３ represents an alkyl group having 1 to 6 carbon atoms or a substituted or unsubstituted aryl group having 6 to 12 carbon atoms. J, k, m, and n each independently represent 0 or 1, provided that at least one of J and k is 1.

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