Dicyanonaphthaleneylidene derivatives and organic light-emitting devices using the same

Abstract

This invention provides a dicyanonaphthaleneylidene derivative with excellent thermal stability and low deposition temperature, making it useful as a hole injection material, and an organic light-emitting element using the same. [Solution] A dicyanonaphthaleneylidene derivative represented by general formula (1). In formula (1), Ar is an aryl group having 6 to 60 ring-forming carbon atoms, a pyridyl group, a quinolyl group, an alkyl group having 1 to 50 carbon atoms, a cycloalkyl group having 3 to 50 ring-forming carbon atoms, an aralkyl group having 7 to 50 carbon atoms, an alkoxy group having 1 to 50 carbon atoms, an aryloxy group having 6 to 50 ring-forming carbon atoms, an arylthio group having 6 to 50 ring-forming carbon atoms, an alkoxycarbonyl group having 2 to 50 carbon atoms, an amino group substituted with an aryl group having 6 to 50 ring-forming carbon atoms, a halogen atom, a trifluoromethyl group, a cyano group, a nitro group, a hydroxyl group, or a carboxyl group. R1 to R6 are a hydrogen atom, a halogen atom, a substituted or unsubstituted fluoroalkyl group, or a cyano group. [Formula 1] JPEG2026050117000039.jpg3389

Description

Technical Field

[0001] The present invention relates to an electron-accepting organic material used as a material for an acceptor layer of a photoelectric conversion layer, and an organic light-emitting device using the same.

Background Art

[0002] Organic electroluminescent devices (OLEDs, organic electroluminescent diodes) are self-emitting, have high brightness, a wide viewing angle, faster response, and a simple manufacturing process, and are thus often used in industrial displays. In recent years, with the development and widespread application of electronic products such as mobile phones, personal digital assistants, and notebook computers, the demand for flat display devices that consume less power and occupy less space has been increasing.

[0003] Conventional organic electroluminescent devices generally rely on intrinsic semiconductor materials and have an undoped hole injection layer, and have higher driving voltages and power consumption compared to the same type of liquid crystal display (LCD). To reduce the driving voltage and power consumption of organic electroluminescent diodes, OLEDs having a p-i-n structure are known. Specifically, the OLED has a p-doped hole injection layer.

[0004] Also, p-i-n OLEDs using F4-TCNQ (2,3,5,6-tetrafluoro-7,7,8,8-tetracyano-p-quinodimethane) as a p-dopant and m-MTDATA (4,4’,4”-tris(3-methylphenylphenylamino)-triphenylamine) as a host of the p-doped layer are known.

[0005] Patent Document 1 discloses an image display system including an organic electroluminescent diode in which a hole injection layer contains a compound having an F4-TCNQ structure.

Prior Art Documents

[0006] [Patent Document 1] Japanese Patent Publication No. 2008-244430 [Overview of the project] [Problems that the invention aims to solve]

[0007] However, F4-TCNQ has poor thermal stability and is prone to decomposition during evaporation, which reduces the reliability and performance of OLEDs. Furthermore, because F4-TCNQ has a low deposition temperature, it is difficult to control the amount of F4-TCNQ dopant.

[0008] In view of the above problems, the present invention aims to provide a dicyanonaphthaleneylidene derivative that has excellent thermal stability, a low deposition temperature, and is useful as an acceptor-containing layer, as well as an organic light-emitting element using the same. [Means for solving the problem]

[0009] To achieve the above objective, the first configuration of the present invention is a dicyanonaphthaleneylidene derivative represented by the following general formula (1). [ka] In formula (1), Ar is a substituted or unsubstituted ring-forming aryl group having 6 to 60 carbon atoms, a substituted or unsubstituted pyridyl group, a substituted or unsubstituted quinolyl group, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted ring-forming cycloalkyl group having 3 to 50 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 50 carbon atoms, a substituted or unsubstituted ring-forming aryloxy group having 6 to 50 carbon atoms, a substituted or unsubstituted ring-forming arylthio group having 6 to 50 carbon atoms, a substituted or unsubstituted alkoxycarbonyl group having 2 to 50 carbon atoms, an amino group substituted with a substituted or unsubstituted ring-forming aryl group having 6 to 50 carbon atoms, a halogen atom, a trifluoromethyl group, a cyano group, a nitro group, a hydroxyl group, or a carboxyl group. R1 to R6 may be the same or different from each other, and are a hydrogen atom, a halogen atom, a substituted or unsubstituted fluoroalkyl group, or a cyano group. [Effects of the Invention]

[0010] According to the first configuration of the present invention, by using the compound represented by formula (1) above as the material for the acceptor-containing layer of the organic light-emitting element, it is possible to form a hole injection layer with excellent thermal stability and a low deposition temperature, and the amount of dopant can be easily controlled. Therefore, the reliability and performance of the organic light-emitting element are improved. [Brief explanation of the drawing]

[0011] [Figure 1] Partial cross-sectional view of an organic electroluminescent element 100 according to the first embodiment of the present invention [Figure 2] Partial cross-sectional view of an organic electroluminescent element 100 according to a second embodiment of the present invention. [Modes for carrying out the invention]

[0012] [1. Configuration of an Organic Electroluminescent Element] First, the organic electroluminescent element using the dicyanonaphthaleneylidene derivative of the present invention will be described. Figure 1 is a partial cross-sectional view of an organic electroluminescent element (hereinafter simply referred to as an organic light-emitting element) 100 according to the first embodiment of the present invention. The organic light-emitting element 100 comprises a substrate 1, an anode 2, a hole injection layer 3, a hole transport layer 4, a light-emitting layer 5, a donor-containing layer 6, an acceptor-containing layer 7, and a light-transmitting cathode 8.

[0013] <Circuit board> The substrate 1 is not particularly limited as long as it can be used for the organic light-emitting element 100. The substrate 1 may be transparent or opaque. Examples of transparent substrates include transparent rigid substrates such as glass like quartz glass or synthetic quartz plates, and transparent flexible substrates such as transparent resin films or optical resin plates. Transparent flexible substrates have advantages such as ease of processing, reduced manufacturing costs, lighter weight, resistance to breakage, and applicability to curved surfaces.

[0014] <Anode> Anode 2 is a hole injection electrode. Examples of materials that can be used as anode 2 include gold (Au), silver (Ag), cobalt (Co), nickel (Ni), platinum (Pt), carbon (C), indium tin oxide (ITO), tin oxide (SnO2), fluorine-doped tin oxide (FTO), and zinc oxide (ZnO).

[0015] Furthermore, the material of the anode 2 is appropriately selected considering whether or not the organic light-emitting element 100 emits light from the side facing the substrate 1. If the substrate 1 is a transparent substrate and light is emitted from the side facing the substrate 1, it is preferable that the anode 2 be a transparent electrode. Examples of materials used when the anode 2 is a transparent electrode include indium zinc oxide (IZO), ITO, FTO, ZnO-Al, and Zn-Sn-O.

[0016] The anode 2 may be a single layer. Also, the anode 2 may be composed of a plurality of layers having different work functions.

[0017] The anode 2 may be formed in a sheet shape over the entire surface of the substrate 1, or may be formed in a pattern on the substrate 1. Also, the shape of the anode 2 may be a flat shape or a concavo-convex shape. Examples of the concavo-convex shape include a texture structure shape, a pyramid structure shape, a waveform structure shape, a comb shape structure shape, and a nanopillar structure shape. The anode 2 is formed by a method such as sputtering, electron beam evaporation, thermal evaporation, or chemical vapor deposition.

[0018] <Hole injection layer> The hole injection layer 3 is laminated between the anode electrode 2 and the hole transport layer 4. The hole injection layer 3 is provided so that holes can be easily injected (moved) from the anode 2 (hole injection electrode) to the hole transport layer 4.

[0019] <Hole transport layer> The hole transport layer 4 is laminated between the hole injection layer 3 and the light-emitting layer 5. The hole transport layer 4 is provided so that holes can be easily injected (moved) from the hole injection layer 3 to the light-emitting layer 5. By laminating the hole injection layer 3 and the hole transport layer 4, the hole injection efficiency from the anode 2 to the light-emitting layer 5 is increased, and the light-emitting efficiency of the organic light-emitting device 100 is improved.

[0020] <Light-emitting layer> The light-emitting layer 5 is laminated between the hole transport layer 4 and the donor-containing layer 6. The light-emitting layer 5 contains a light-emitting material that emits light by the recombination energy of holes injected from the anode 2 and electrons injected from the light-transmissive cathode 8. The light-emitting layer 5 may use the light-emitting material alone or may contain a light-emitting material and a host material. In order for the organic light-emitting device 100 to exhibit high light-emitting efficiency, it is important to confine singlet excitons and triplet excitons generated in the light-emitting material within the light-emitting material. Therefore, it is preferable to add a host material in addition to the light-emitting material in the light-emitting layer 5.

[0021] As the luminescent material, one or more compounds selected from the conventionally known group of compounds can be used. As the host material, an organic compound having at least one of the excitation singlet energy and excitation triplet energy higher than that of the luminescent material can be used. Preferably, the host material is an organic compound that has hole transport ability, electron transport ability, prevents the emission from becoming longer wavelengths, and has a high glass transition temperature. The emission from the luminescent layer 5 originates from the luminescent material contained in the luminescent layer 5. This emission includes both fluorescence emission and delayed fluorescence emission. However, some or partial emission may originate from the host material.

[0022] <Donor-containing layer> The donor-containing layer 6 is laminated between the light-emitting layer 5 and the acceptor-containing layer 7. The donor-containing layer 6 is a layer that extracts electrons from the acceptor-containing layer 7 and injects them into the light-emitting layer 5 (donates electrons). By providing the donor-containing layer 6, the large difference in affinity levels between the light-emitting layer 5 and the acceptor-containing layer 7 can be eliminated, making it easier for the donor-containing layer 6 to accept electrons from the acceptor-containing layer 7.

[0023] <Acceptor-containing layer> The acceptor-containing layer 7 is laminated between the donor-containing layer 6 and the light-transmitting cathode 8. In this embodiment, the acceptor-containing layer 7 is directly laminated to the donor-containing layer 6. That is, the donor-containing layer 6 and the acceptor-containing layer 7 are in contact with each other. The acceptor-containing layer 7 is provided so that electrons can be easily injected (transferred) from the light-transmitting cathode 8 (electron injection electrode) to the donor-containing layer 6. An easily reducible organic compound can be used as the acceptor-containing layer 7. The ease of reduction of a compound can be measured by its reduction potential. In this invention, a compound having a reduction potential of -0.8V or higher, more preferably -0.3V or higher, and particularly preferably a value greater than the reduction potential of tetracyanoquinodimethane (TCNQ) (approximately 0V), is preferred, using a saturated calomel (SCE) electrode as the reference electrode.

[0024] By providing an acceptor-containing layer 7 between the donor-containing layer 6 and the light-transmitting cathode 8, the acceptors contained in the acceptor-containing layer 7 extract electrons from the contact surface between it and the light-transmitting cathode 8. Since the acceptor-containing layer 7 is electron-transporting, electrons are transported from this contact surface into the acceptor-containing layer 7 in the direction of the donor-containing layer 6. Furthermore, electrons are injected from the donor-containing layer 6 in the direction of the light-emitting layer 5. Meanwhile, holes from the anode 2 are injected into the hole injection layer 3 and the hole transport layer 4, and further injected into the light-emitting layer 5. In the light-emitting layer 5, holes and electrons recombine, generating light emission.

[0025] In the organic light-emitting element 100 of this embodiment, by providing an acceptor-containing layer 7 and a donor-containing layer 6 between the light-transmitting cathode 8 and the light-emitting layer 5, the injection (movement) of electrons from the light-transmitting cathode 8 to the light-emitting layer 5 is facilitated, thereby reducing the driving voltage of the organic light-emitting element 100, increasing efficiency, and extending its lifespan.

[0026] In the organic light-emitting element 100 of this embodiment, the acceptor-containing layer 7 contains a dicyanonaphthaleneylidene derivative represented by the following general formula (1). The acceptor-containing layer 7 may contain only the dicyanonaphthaleneylidene derivative represented by general formula (1), or it may further contain additives. Conventional known additives such as interfacial treatment agents can be used as additives.

[0027] [ka]

[0028] In formula (1), Ar is a substituted or unsubstituted ring-forming aryl group having 6 to 60 carbon atoms, a substituted or unsubstituted pyridyl group, a substituted or unsubstituted quinolyl group, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted ring-forming cycloalkyl group having 3 to 50 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 50 carbon atoms, a substituted or unsubstituted ring-forming aryloxy group having 6 to 50 carbon atoms, a substituted or unsubstituted ring-forming arylthio group having 6 to 50 carbon atoms, a substituted or unsubstituted alkoxycarbonyl group having 2 to 50 carbon atoms, an amino group substituted with a substituted or unsubstituted ring-forming aryl group having 6 to 50 carbon atoms, a halogen atom, a trifluoromethyl group, a cyano group, a nitro group, a hydroxyl group, or a carboxyl group. R1 to R6 may be the same or different from each other, and are a hydrogen atom, a halogen atom, a substituted or unsubstituted fluoroalkyl group, or a cyano group.

[0029] Specific examples of dicyanonaphthaleneylidene derivatives represented by general formula (1) include compounds (1-1) to (1-8) represented by the following chemical formulas. Thermophysical property data of compounds (1-1) to (1-8) (vacuum level 5 × 10⁻⁶ -3 Table 1 shows the sublimation temperature at Pa compared to F4-TCNQ.

[0030] [ka]

[0031] [ka]

[0032] [ka]

[0033] [ka]

[0034] [ka]

[0035] [ka]

[0036] [ka]

[0037] [ka]

[0038] [Table 1]

[0039] As shown in Table 1, the deposition temperatures of compounds (1-1) to (1-8) are all above 200°C, which is significantly higher than the deposition temperature of F4-TCNQ (100°C). Therefore, it can be seen that the amount of dopant is easier to control compared to F4-TCNQ.

[0040] By using the compound represented by formula (1) above as the dopant material (electron-accepting material) constituting the hole injection layer 3, the mobility of charge (electrons) can be improved, thereby increasing the luminescence efficiency of the organic light-emitting element 100. Furthermore, the compound represented by formula (1) above has excellent thermal stability and a low deposition temperature, which allows for easy manufacturing of the organic light-emitting element 100 and improves its reliability.

[0041] The compounds represented by formula (1) above exhibit electron-withdrawing properties based on the R1-R6 groups. The more electron-withdrawing groups there are as substituents on the Ar group, the greater the electron-withdrawing properties of the compound itself, and the better its performance as a dopant. For example, compounds (1-7) have no electron-withdrawing substituents on the Ar group, and only the nitrile group and fluorine atom exhibit electron-withdrawing properties. Examples of compounds in which the Ar group does not have electron-withdrawing groups include compounds (1-9)-(1-11) represented by the following chemical formulas.

[0042] [ka]

[0043] [ka]

[0044] [ka]

[0045] Compounds (1-1) to (1-4) have one electron-withdrawing trifluoromethyl, nitrile, or nitro group as a substituent on the Ar group. Examples of compounds in which the Ar group has one electron-withdrawing group include compounds (1-12) to (1-17) represented by the following chemical formulas.

[0046] [ka]

[0047] [ka]

[0048] [ka]

[0049] [ka]

[0050] [ka]

[0051] [ka]

[0052] Compound (1-5) has two electron-withdrawing trifluoromethyl groups as substituents on the Ar group. Examples of compounds in which the Ar group has two electron-withdrawing groups include compounds (1-18) to (1-22) represented by the following chemical formulas.

[0053] [ka]

[0054] [ka]

[0055] [ka]

[0056] [ka]

[0057] [ka]

[0058] Compounds (1-6) and (1-8) have five electron-withdrawing fluorine atoms or nitrile groups as substituents on the Ar group. Examples of compounds in which the Ar group has three or more electron-withdrawing groups include compounds (1-23) to (1-27) represented by the following chemical formulas.

[0059] [ka]

[0060] [ka]

[0061] [ka]

[0062] [ka]

[0063] [ka]

[0064] <Light transparent cathode> The light-transmitting cathode 8 is an electron injection electrode laminated on the acceptor-containing layer 7. The light-transmitting cathode 8 is positioned opposite the anode 2. In this embodiment, the light-transmitting cathode 8 is directly laminated on the acceptor-containing layer 7. That is, the acceptor-containing layer 7 and the light-transmitting cathode 8 are in contact with each other. The light-transmitting cathode 8 is not particularly limited as long as it is conductive. The material of the light-transmitting cathode 8 is appropriately selected, for example, taking into consideration the material of the acceptor-containing layer 7.

[0065] Examples of materials used as the material for the light-transmitting cathode 8 include indium tin oxide (ITO), tin oxide (SnO2), fluorine-doped tin oxide (FTO), and zinc oxide (ZnO).

[0066] The light-transmitting cathode 8 may be a single layer. The second electrode 6 may also be composed of multiple layers having different work functions. The light-transmitting cathode 8 may be formed in a sheet shape over the entire surface of the acceptor-containing layer 7, or it may be formed in a pattern shape on the acceptor-containing layer 7.

[0067] <Other components> The organic light-emitting element 100 may further comprise other components in addition to the substrate 1, anode 2, hole injection layer 3, hole transport layer 4, light-emitting layer 5, donor-containing layer 6, acceptor-containing layer 7, and light-transmitting cathode 8 described above, as needed. Examples of other components include a protective sheet layer, filler layer, barrier layer, protective hard coat layer, strength support layer, anti-fouling layer, high light reflectivity layer, ultraviolet blocking layer, infrared blocking layer, and sealing layer. Furthermore, adhesive layers may be laminated between each layer of the organic light-emitting element 100, as needed.

[0068] The organic light-emitting element 100 of this embodiment is not limited to the configuration shown in Figure 1. For example, the hole injection layer 3 and the hole transport layer 4 are arbitrary layers and can be omitted, and an electron transport layer or the like can be laminated between the light-emitting layer 5 and the donor-containing layer 6. The hole injection layer 3, the hole transport layer 4, the light-emitting layer 5, the electron transport layer, etc. correspond to the organic thin film layers in the organic light-emitting element 100 of this embodiment.

[0069] The configuration of the organic light-emitting element 100 of the present invention has been described above using the organic light-emitting element 100 of the first embodiment shown in Figure 1 as an example. However, the present invention is not limited to the configuration of the organic light-emitting element 100 of the first embodiment. For example, a stacked type multi-photon emission element (MPE element) may be used in which two or more light-emitting units are sandwiched between an anode 2 and a light-transmitting cathode 8, and a charge generation layer is stacked between the light-emitting units.

[0070] Figure 2 is a schematic cross-sectional view of an organic light-emitting element 100 according to a second embodiment of the present invention. The organic light-emitting element 100 of this embodiment comprises, in this order, an anode 2, a first light-emitting unit 10, a charge generation layer 11, a second light-emitting unit 12, a donor-containing layer 6, an acceptor-containing layer 7, and a light-transmitting cathode 8 on a substrate 1. The two light-emitting units 10 and 12 each have a single-layer or multilayer structure having at least a light-emitting layer. For example, it is preferable that the light-emitting units 10 and 12 have a multilayer structure in which a hole transport layer, a light-emitting layer, and an electron transport layer are stacked from the anode 2 side.

[0071] The organic light-emitting element 100 has the same configuration as the organic light-emitting element 100 of the first embodiment shown in Figure 1, except that it has two light-emitting units. In other words, the organic light-emitting element 100 of the first embodiment has an element configuration having one light-emitting unit consisting of a hole injection layer 3, a hole transport layer 4, and a light-emitting layer 5.

[0072] In this embodiment, for example, by changing the material of the light-emitting layer constituting each light-emitting unit 10, 12 to produce different light-emitting colors, an organic light-emitting element 100 that emits white light can be obtained.

[0073] The organic light-emitting element 100 of this embodiment is not limited to the configuration shown in Figure 2. For example, in each light-emitting unit 10, 12 of the organic light-emitting element 100 of this embodiment, the donor-containing layer and acceptor-containing layer described above may be laminated between the light-emitting layer and the charge-generating layer. Specifically, the first light-emitting unit 10 may have a configuration in which a hole transport layer, a light-emitting layer, a donor-containing layer, and an acceptor-containing layer are laminated from the anode 2 side.

[0074] Furthermore, the present invention is not limited to the embodiments described above, and various modifications are possible without departing from the spirit of the invention. For example, in the embodiments described above, an example was given in which the dicyanonaphthaleneylidene derivative of the present invention was used in the acceptor-containing layer 7 of the organic light-emitting element 100, but it can also be used, for example, as the acceptor layer of an organic solar cell. The effects of the present invention will be described in more detail below with reference to examples. [Examples]

[0075] [Example of synthesis of intermediate product (b-1)] Under a nitrogen atmosphere, at 0°C, 30 mL of anhydrous tetrahydrofuran solution containing 2.81 g (15.2 mmol) of p-trifluoromethylbenzylnitrile (compound B) was added dropwise to 0.75 g (19 mmol) of 60% sodium hydride solution and the mixture was stirred for 1 hour. 2.04 g (7.5 mmol) of octafluoronaphthalene (compound A) was added dropwise to the reaction mixture and the mixture was heated to 80°C and stirred under reflux for 5 hours. After returning to room temperature, the reaction mixture was poured into water, acidified with hydrochloric acid, and the precipitated solid was filtered off. The solid was washed with water to obtain 2.10 g of intermediate product (b-1) (yield 47%). The synthesis scheme is shown below.

[0076] [ka]

[0077] [Example of synthesis of dicyanonaphthaleneylidene derivative (1-1)] Under a nitrogen atmosphere, 1.20 g (2 mmol) of intermediate product (b-1) was dissolved in 20 mL of anhydrous acetonitrile. After cooling the solution to 0°C, 32 g (8 mmol) of 2% bromine water was added dropwise, and the mixture was stirred for 1 hour while returning to room temperature. The reaction mixture was poured into water, the precipitated solid was filtered off, washed twice with water and twice with ether, and dried to obtain 0.60 g of compound (1-1) (yield 50%, H-NMR 600 MHz; 7.7(d,2H), 7.8(d,2H)d6-DMSO). The synthesis scheme is shown below.

[0078] [ka] [Examples]

[0079] [Examples of synthesis of dicyanonaphthaleneylidene derivatives (1-2) to (1-8)] Dicyanonaphthaleneylidene derivatives (1-2) to (1-8) were synthesized in the same manner as in Example 1, except that compounds (A) and (B) were changed. The yields of the intermediate products (b-2) to (b-8) and the dicyanonaphthaleneylidene derivatives (1-2) to (1-8) are shown in Table 2.

[0080] [Table 2] *H-NMR 600MHz 1-3;8.3(d,2H),7.8(d,2H)d6-DMSO [Examples]

[0081] [Example of manufacturing an organic electroluminescent device using a dicyanonaphthalene ilidene derivative as a dopant material] A mixed layer (luminescent layer) of SPIRO-MeOTAD as the host material and compounds (1-1) to (1-5) and (1-8) obtained in Examples 1 and 2 as dopant materials was laminated onto a glass substrate by mixed thermal evaporation in a high vacuum chamber to form Inventions 1 to 6. In addition, a mixed layer (luminescent layer) of SPIRO-MeOTAD and F4-TCNQ was laminated onto a glass substrate to form a comparative example.

[0082] The doping concentration was 5 mol%, and the thin film thickness was 50 nm. The glass substrate had two ITO (indium tin oxide) strips as electrodes for the thin film. These two ITO strips were spaced 1 mm apart. The conductivity of the mixed layer was measured from the current-voltage characteristics of the thin film. The results are shown in Table 3.

[0083] [Table 3]

[0084] As is clear from Table 3, Inventions 1 to 6, which used compounds (1-1) to (1-5) and (1-8) as dopant materials, showed conductivity equal to or better than that of the comparative example using F4-TCNQ as the dopant material. In particular, Inventions 2, 3, and 6, which used compounds (1-2), (1-3), and (1-8), showed higher conductivity than the comparative example. From these results, it was confirmed that the OLED properties were improved by using dicyanonaphthalene ilidene derivatives as dopant materials. [Industrial applicability]

[0085] The present invention is applicable to dicyanonaphthaleneylidene derivatives used as hole transport layer materials, and to organic light-emitting devices using the same. By utilizing the present invention, it is possible to provide dicyanonaphthaleneylidene derivatives that have excellent thermal stability and low deposition temperatures, making them useful as hole transport layers, and organic light-emitting devices using the same. [Explanation of Symbols]

[0086] 1 circuit board 2 Anode 3. Hole injection layer 4. Hole transport layer 5. Emitting layer 6. Donor-containing layer 7. Acceptor-containing layer 8 Light-transparent cathode 10. First light-emitting unit 11 Charge generation layer 12. Second light-emitting unit 100 Organic electroluminescent elements (organic light-emitting devices)

Claims

1. A dicyanonaphthaleneylidene derivative represented by the following general formula (1). 【Chemistry 1】 (In formula (1), Ar is an unsubstituted ring-forming aromatic ring having 6 to 24 carbon atoms, an unsubstituted heterocycle having 5 to 24 carbon atoms, a substituted ring-forming aryl group having 6 to 60 carbon atoms, a pyridyl group, a quinolyl group, a substituted or unsubstituted alkyl group having 1 to 50 carbon atoms, a substituted or unsubstituted cycloalkyl group having 3 to 50 carbon atoms, a substituted or unsubstituted aralkyl group having 7 to 50 carbon atoms, a substituted or unsubstituted alkoxy group having 1 to 50 carbon atoms, a substituted or unsubstituted aryloxy group having 6 to 50 carbon atoms, a substituted or unsubstituted aryl thio group having 6 to 50 carbon atoms, a substituted or unsubstituted alkoxycarbonyl group having 2 to 50 carbon atoms, an amino group substituted with a substituted or unsubstituted ring-forming aryl group having 6 to 50 carbon atoms, a halogen atom, a trifluoromethyl group, a cyano group, a nitro group, a hydroxyl group, or a carboxyl group. 1 ~R 4 These elements may be identical or different from each other, and are a hydrogen atom, a halogen atom, a substituted or unsubstituted fluoroalkyl group, or a cyano group.

2. The dicyanonaphthaleneylidene derivative according to claim 1, characterized in that the general formula (1) is any of the following chemical formulas (1-2), (1-3), or (1-8). 【Transformation 3】 【Chemistry 4】 【Chemistry 9】

3. circuit board and Anode stacked on the aforementioned substrate, One or more organic thin film layers, including a light-emitting layer, are stacked on the anode, A donor-containing layer laminated on the aforementioned organic thin film layer, An acceptor-containing layer is laminated on the donor-containing layer, A light-transmitting cathode laminated on the acceptor-containing layer, Equipped with, The donor-containing layer and the acceptor-containing layer are in contact with each other, and the acceptor-containing layer and the light-transmitting cathode are in contact with each other. An organic electroluminescent element wherein the acceptor-containing layer comprises the dicyanonaphthaleneylidene derivative described in claim 1 or claim 2.

4. The organic electroluminescent element according to claim 3, wherein one or more organic thin film layers including the light-emitting layer constitute two or more light-emitting units stacked via a charge-generating layer.

5. The organic electroluminescent element according to claim 4, wherein at least one material constituting the light-emitting layer of the light-emitting unit is different from the material constituting the light-emitting layer of the other light-emitting units.

6. The organic electroluminescent element according to claim 3, wherein the light-emitting layer emits white light.

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