JP4065552B2 - Organic light emitting device - Google Patents

Description

The present invention relates to organic light emitting devices.

  An organic light emitting device has a fluorescent compound or a phosphorescent compound by injecting electrons and holes from each electrode by sandwiching a thin film containing a fluorescent organic compound or a phosphorescent organic compound between an anode and a cathode. This is an element that utilizes the light emitted when the exciton is generated and the exciton returns to the ground state.

In a study of Kodak Company in 1987 (Appl. Phys. Lett. 51, 913 (1987)), ITO was used for the anode and magnesium-silver alloy for the cathode, and an aluminum quinolinol complex was used as the electron transport material and the light emitting material. It is reported that the device has a function separation type two-layer structure using a triphenylamine derivative as a transport material, and emits light of about 1000 cd / m ^{2 at} an applied voltage of about 10V. Related patents include US Pat. No. 4,539,507, US Pat. No. 4,720,432, US Pat. No. 4,885,211 and the like.

  In addition, by changing the type of the fluorescent organic compound, light emission from ultraviolet to infrared is possible, and recently, various compounds have been actively researched. For example, US Pat. No. 5,151,629, US Pat. No. 5,409,783, US Pat. No. 5,382,477, JP-A-2-247278, JP-A-3-255190, JP-A-5-202356. No. 9, JP-A-9-202878, JP-A-9-227576, and the like.

  In recent years, many studies have been made on using phosphorescent compounds as light emitting materials and using triplet state energy for EL light emission. A group of Princeton University has reported that an organic light-emitting device using an iridium complex as a light-emitting material exhibits high luminous efficiency (Nature, 395, 151 (1998)).

  In addition to organic light-emitting elements using low molecular materials as described above, organic light-emitting elements using conjugated polymers have been reported by a group of Cambridge University (Nature, 347, 539 (1990)). Yes. In this report, light emission was confirmed in a single layer by forming a film of polyphenylene vinylene (PPV) in a coating system.

  Related patents for organic light emitting devices using conjugated polymers include US Pat. No. 5,247,190, US Pat. No. 5,514,878, US Pat. No. 5,672,678, and Japanese Patent Laid-Open No. 4-145192. JP, 5-247460, A, etc. are mentioned.

  As described above, recent advances in organic light-emitting devices are remarkable, and their features are high brightness, variety of emission wavelengths, high-speed response, low profile, and light-emitting devices with low applied voltage. Suggests the possibility to.

  However, under the present circumstances, light output with higher brightness or higher conversion efficiency is required. In addition, there are still many problems in terms of durability, such as changes over time due to long-term use and deterioration due to atmospheric gas containing oxygen or moisture. Furthermore, it is necessary to emit blue, green, and red light with good color purity when considering application to a full color display or the like, but these problems are still not sufficient.

  An object of the present invention is to provide a novel fluorene compound.

  Another object of the present invention is to provide an organic light emitting device that uses a specific fluorene compound and has an extremely high efficiency and high luminance light output.

  Another object of the present invention is to provide an extremely durable organic light emitting device.

  It is another object of the present invention to provide an organic light emitting device that is easy to manufacture and can be produced at a relatively low cost.

That is, the organic light emitting device of the present invention is an organic light emitting device having at least a pair of electrodes composed of an anode and a cathode, a light emitting layer composed of an organic compound sandwiched between the pair of electrodes, and a hole transport layer.
The light emitting layer contains a fluorene compound represented by the following structural formula , and the fluorene compound is a kind of a fluorene compound represented by the following general formula [I].

Wherein R ₁ and R ₂ are a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, or a substituted amino group R ₁ and R ₂ bonded to different fluorene groups may be the same or different, and R ₁ and R ₂ bonded to the same fluorene group are the same. R ₃ and R ₄ may be a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic ring. represents a group, together R ₃ which binds to a different fluorene group, R ₄ each other or different be the same, R ₃ and R ₄ bonded to the same fluorene group, the .Ar ₁ and Ar ₂ may be different even a total of three or more substituted or unsubstituted fused polycyclic aromatic group or a benzene ring and a heterocyclic total three or more benzene rings Represents a condensed polycyclic heterocyclic group bonded to a fluorene group with a substituted or unsubstituted carbon, Ar ₁ and Ar ₂ may be the same or different, and n is an integer of 1 to 10, preferably Represents an integer of 1 to 3.)

The organic light-emitting device of the present invention is further characterized in that the hole transport layer is composed of an aminofluorene compound represented by the following structural formula .

  As described above, the organic light-emitting device using the fluorene compound represented by the general formula [I] can emit light with high luminance at a low applied voltage and has excellent durability. In particular, the organic layer containing the condensed polycyclic compound of the present invention is excellent as an electron transport layer and also excellent as a light emitting layer.

  Furthermore, the device can be formed using vacuum deposition, casting method, or the like, and a device with a large area can be easily manufactured at a relatively low cost.

  Hereinafter, the present invention will be described in detail. Hereinafter, the fluorene compound represented by the general formula [I] will be described. 1 is the fluorene compound of the present invention.

  First, the fluorene compound of the present invention will be described.

  The fluorene compound of the present invention is represented by the above general formula [I].

Here, at least one of Ar ₁ and Ar ₂ is preferably a condensed polycyclic aromatic group represented by the following general formula [II].

(In the formula, R ₅ represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a substituted amino group, or a cyano group. Or represents a halogen atom.)

  Furthermore, it is more preferable that it is represented by any one of the following structural formulas.

Moreover, it is preferable that at least one of Ar ₁ and Ar ₂ is a condensed polycyclic aromatic group represented by any one of the following general formulas [III] to [IX].

Wherein R _{6 to} R ₁₂ are a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, or a substituted amino group. Represents a cyano group or a halogen atom.)

  Specific examples of the substituent in the general formulas [I] to [IX] are shown below.

  Examples of the alkyl group include a methyl group, an ethyl group, an n-propyl group, an iso-propyl group, an n-butyl group, a ter-butyl group, and an octyl group.

  Examples of the aralkyl group include a benzyl group and a phenethyl group.

  Examples of the aryl group include a phenyl group, a biphenyl group, and a terphenyl group.

  Examples of the heterocyclic group include thienyl group, pyrrolyl group, pyridyl group, oxazolyl group, oxadiazolyl group, thiazolyl group, thiadiazolyl group, and tertenyl group.

  Examples of the substituted amino group include a dimethylamino group, a diethylamino group, a dibenzylamino group, a diphenylamino group, a ditolylamino group, and a dianisolylamino group.

  Examples of the halogen atom include fluorine, chlorine, bromine and iodine.

  Examples of the condensed polycyclic aromatic group include a fluorenyl group, a naphthyl group, a fluoranthenyl group, an anthryl group, a phenanthryl group, a pyrenyl group, a tetracenyl group, a pentacenyl group, a triphenylenyl group, and a perylenyl group.

  Examples of the condensed polycyclic heterocyclic group include a carbazolyl group, an acridinyl group, and a phenanthroyl group.

  Examples of the substituent that the substituent may have include an alkyl group such as a methyl group, an ethyl group, and a propyl group, an aralkyl group such as a benzyl group and a phenethyl group, an aryl group such as a phenyl group and a biphenyl group, a thienyl group, Heterocyclic groups such as pyrrolyl group and pyridyl group, amino groups such as dimethylamino group, diethylamino group, dibenzylamino group, diphenylamino group, ditolylamino group, and dianisolylamino group, methoxyl group, ethoxyl group, propoxyl group, Examples include alkoxyl groups such as phenoxyl groups, cyano groups, halogen atoms such as fluorine, chlorine, bromine and iodine.

  Next, typical examples of the fluorene compound of the present invention are listed below, but the present invention is not limited thereto.

  The fluorene compound of the present invention can be synthesized by a generally known method, for example, Suzuki coupling method using a palladium catalyst (for example, Chem. Rev. 1995, 95, 2457-2483), Yamamoto using a nickel catalyst. It can be obtained by a synthesis method such as a method (for example, Bull. Chem. Soc. Jpn. 51, 2091, 1978) or a method for synthesis using an aryltin compound (for example, J. Org. Chem., 52, 4296, 1987). .

  The fluorene compound of the present invention is a compound excellent in electron transport property, light emission property and durability as compared with conventional compounds, and is useful as a layer containing an organic compound of an organic light emitting device, particularly as an electron transport layer and a light emitting layer. In addition, a layer formed by a vacuum deposition method, a solution coating method, or the like is hardly crystallized and has excellent temporal stability.

  Next, the organic light emitting device of the present invention will be described in detail.

  The organic light-emitting device of the present invention includes the organic compound in an organic light-emitting device having at least a layer including a pair of electrodes composed of an anode and a cathode and one or more organic compounds sandwiched between the pair of electrodes. At least one of the layers contains at least one fluorene compound represented by the above general formula [I].

  In the organic light-emitting device of the present invention, it is preferable that at least the electron transport layer or the light-emitting layer in the layer containing an organic compound contains at least one of the fluorene compounds.

  In the organic light emitting device of the present invention, the fluorene compound represented by the general formula [I] is formed between the anode and the cathode by a vacuum deposition method or a solution coating method. The thickness of the organic layer is less than 10 μm, preferably 0.5 μm or less, more preferably 0.01 to 0.5 μm.

  In the organic light-emitting device of the present invention, at least a light-emitting layer among the layers containing an organic compound is represented by at least one fluorene compound represented by the above general formula [I] and the following general formulas [X] to [XIV]. It is preferable that the arylamine compound or the acetylene compound represented by the following general formula [XV] is contained as a preferred embodiment.

Wherein R ₁₃ and R ₁₄ represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and are different from each other. R ₁₃ mutually bonded to fluorene group, R ₁₄ to each other may be different even in the same, R ₁₃ and R ₁₄ bonding to the same fluorene group may be different even in the same .R ₁₅ and R _{16 each} represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a cyano group, or a halogen atom. each other R ₁₅ which bonded to different fluorene groups R ₁₆ may be different even in the same, R ₁₅ and R ₁₆ bonding to the same fluorene group, the same der .Ar ₃ may be different even if, Ar _4, Ar ₅ and Ar ₆ are substituted or unsubstituted aromatic group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group Alternatively, it represents a substituted or unsubstituted condensed polycyclic heterocyclic group, and Ar ₃ , Ar ₄ , Ar ₅ and Ar ₆ may be the same or different, and m represents an integer of 1 to 10. )

Wherein R ₁₇ and R ₁₈ represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and are different from each other. each other R ₁₇ to bind to the fluorene group, together R ₁₈ may be different even in the same, R ₁₇ and R ₁₈ bonding to the same fluorene group may be different even in the same .R ₁₉ and R _{20 each} represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a cyano group or a halogen atom. each other R ₁₉ binding to different fluorene group, R ₂₀ to each other may be different even in the same, R ₁₉ and R ₂₀ bonding to the same fluorene group, the same der .Ar ₇ and Ar ₈ may be different even if is a divalent substituted or unsubstituted aromatic group or a substituted or unsubstituted heterocyclic group, Ar ₇ and Ar ₈ may be the same Ar ₉ , Ar ₁₀ , Ar ₁₁ and Ar ₁₂ may be substituted or unsubstituted aromatic group, substituted or unsubstituted heterocyclic group, substituted or unsubstituted condensed polycyclic aromatic group or substituted Alternatively, it represents an unsubstituted condensed polycyclic heterocyclic group, and Ar ₉ , Ar ₁₀ , Ar ₁₁ and Ar ₁₂ may be the same or different, and p represents an integer of 1 to 10.

Wherein R ₂₁ and R ₂₂ represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and are different from each other. each other R ₂₁ to bind to the fluorene group, together R ₂₂ may be different even in the same, R ₂₁ and R ₂₂ bonding to the same fluorene group may be different even in the same .R ₂₃ and R _{24 each} represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a cyano group, or a halogen atom. each other R ₂₃ binding to different fluorene group, R ₂₄ to each other may be different even in the same, R ₂₃ and R ₂₄ bonding to the same fluorene group, the same der Good .Ar ₁₃ and Ar ₁₄ be different even represent a substituted or unsubstituted aromatic group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group or a substituted or unsubstituted Represents a condensed polycyclic heterocyclic group, Ar ₁₃ and Ar ₁₄ may be the same or different, Ar ₁₅ represents a divalent substituted or unsubstituted aromatic group or a substituted or unsubstituted heterocyclic ring; And q represents an integer of 1 to 10.)

(Wherein R ₂₅ and R ₂₆ are a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a cyano group, or R ₂₅ and R ₂₆ bonded to different phenylene groups may be the same or different, and R ₂₅ and R ₂₆ bonded to the same phenylene group may be the same or different. Ar ₁₆ and Ar ₁₇ represent a divalent substituted or unsubstituted aromatic group or a substituted or unsubstituted heterocyclic group, and Ar ₁₆ and Ar ₁₇ may be the same or different. which may .Ar _18, Ar _19, Ar ₂₀ and Ar ₂₁ are a substituted or unsubstituted aromatic group, a substituted or unsubstituted heterocyclic group, there condensed polycyclic aromatic group or substituted substituted or unsubstituted Represents an unsubstituted fused polycyclic heterocyclic _{group, Ar 18, Ar 19, Ar} 20 and Ar ₂₁ are optionally .r be different even in the same represents an integer of 1 to 10.)

Wherein R ₂₇ and R ₂₈ are a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a cyano group or R ₂₇ and R ₂₈ bonded to different phenylene groups may be the same or different, and R ₂₇ and R ₂₈ bonded to the same phenylene group may be the same or different. Ar ₂₂ and Ar ₂₃ are a substituted or unsubstituted aromatic group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group, or a substituted or unsubstituted condensed polycyclic ring. represents a heterocyclic group, Ar ₂₂ and Ar ₂₃ are good .Ar ₂₂ and Ar ₂₃ be different even in the same, the mosquitoes with N which are bonded Ar ₂₂ and Ar ₂₃ bonded to each other Good .Ar ₂₄ be formed Bazoru ring, .s which represents a divalent substituted or unsubstituted aromatic group or a substituted or unsubstituted heterocyclic group represents an integer of 1 to 10.)

(In the formula, Ar ₂₅ and Ar ₂₆ are a substituted or unsubstituted aromatic group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group, or a substituted or unsubstituted condensed polycyclic heterocyclic group, Represents a cyclic group, and Ar ₂₅ and Ar ₂₆ may be the same or different, and t represents an integer of 1 to 5.)

  Specific examples of the substituents in the general formulas [X] to [XV] are the same as those in the general formulas [I] to [IX]. The following are representative examples of the arylamine compounds represented by the general formulas [X] to [XIV] and the acetylene compounds represented by the general formula [XV], but the present invention is not limited thereto.

  1 to 6 show preferred examples of the organic light emitting device of the present invention.

  FIG. 1 is a cross-sectional view showing an example of the organic light emitting device of the present invention. FIG. 1 shows a structure in which an anode 2, a light emitting layer 3 and a cathode 4 are sequentially provided on a substrate 1. The light-emitting element used here is useful when the device itself has a hole transport ability, an electron transport ability, and a light-emitting performance, or when a compound having each characteristic is used in combination.

  FIG. 2 is a cross-sectional view showing another example of the organic light emitting device of the present invention. FIG. 2 shows a configuration in which an anode 2, a hole transport layer 5, an electron transport layer 6 and a cathode 4 are sequentially provided on a substrate 1. In this case, the light emitting material is either a hole transporting property or an electron transporting property, or a material having both functions is used for each layer, and it is combined with a simple hole transporting material or an electron transporting material having no light emitting property. This is useful when used. In this case, the light emitting layer 3 is composed of either the hole transport layer 5 or the electron transport layer 6.

  FIG. 3 is a cross-sectional view showing another example of the organic light emitting device of the present invention. FIG. 3 shows a structure in which an anode 2, a hole transport layer 5, a light emitting layer 3, an electron transport layer 6 and a cathode 4 are sequentially provided on a substrate 1. This is a function that separates the functions of carrier transport and light emission, and is used in combination with compounds having hole transport properties, electron transport properties, and light emission properties in a timely manner, and the degree of freedom of material selection is greatly increased. Since various compounds having different emission wavelengths can be used, the emission hue can be diversified. Further, it is possible to effectively confine each carrier or exciton in the central light emitting layer 3 to improve the light emission efficiency.

  FIG. 4 is a cross-sectional view showing another example of the organic light emitting device of the present invention. FIG. 4 shows a configuration in which a hole injection layer 7 is inserted on the anode 2 side with respect to FIG. 3, and is effective in improving the adhesion between the anode 2 and the hole transport layer 5 or improving the hole injection property. Is effective.

  5 and 6 are cross-sectional views showing other examples of the organic light-emitting device of the present invention. 5 and FIG. 6 show a layer (hole blocking layer 8) that prevents holes or excitons (excitons) from passing to the cathode 4 side as compared with FIGS. 3 and 4, between the light emitting layer 3 and the electron transport layer 6. It is the structure inserted in. By using a compound having a very high ionization potential as the hole blocking layer 8, the structure is effective in improving the light emission efficiency.

  However, FIG. 1 to FIG. 6 are very basic device configurations, and the configuration of the organic light emitting device using the compound of the present invention is not limited thereto. For example, various layer configurations such as providing an insulating layer at the interface between the electrode and the organic layer, providing an adhesive layer or an interference layer, and the hole transport layer including two layers having different ionization potentials can be employed.

  The fluorene compound represented by the general formula [I] used in the present invention is a compound excellent in electron transporting property, light emitting property and durability as compared with conventional compounds, and is used in any form of FIGS. be able to.

  In the present invention, a fluorene compound represented by the general formula [I] is used as a constituent component of an electron transport layer or a light emitting layer, and a hole transport compound, a light emitting compound or an electron transport compound known so far is used. Etc. can be used together if necessary.

  Examples of these compounds are given below.

  In the organic light-emitting device of the present invention, the layer containing the fluorene compound represented by the general formula [I] and the layer containing another organic compound are generally prepared by a vacuum deposition method or a coating method by dissolving in a suitable solvent. A thin film is formed. In particular, when a film is formed by a coating method, the film can be formed in combination with an appropriate binder resin.

  The binder resin can be selected from a wide range of binder resins such as polyvinyl carbazole resin, polycarbonate resin, polyester resin, polyarylate resin, polystyrene resin, acrylic resin, methacrylic resin, butyral resin, polyvinyl acetal resin, diallyl phthalate. Resins, phenol resins, epoxy resins, silicone resins, polysulfone resins, urea resins and the like can be mentioned, but are not limited thereto. Moreover, you may mix these 1 type, or 2 or more types as a single or copolymer polymer.

  As the anode material, one having a work function as large as possible is preferable. For example, simple metals such as gold, platinum, nickel, palladium, cobalt, selenium, vanadium or alloys thereof, tin oxide, zinc oxide, indium tin oxide (ITO) Metal oxides such as zinc indium oxide can be used. In addition, conductive polymers such as polyaniline, polypyrrole, polythiophene, and polyphenylene sulfide can also be used. These electrode materials may be used alone or in combination.

  On the other hand, the cathode material preferably has a small work function, and can be used as a single metal or a plurality of alloys such as lithium, sodium, potassium, cesium, calcium, magnesium, aluminum, indium, silver, lead, tin, and chromium. it can. A metal oxide such as indium tin oxide (ITO) can also be used. Further, the cathode may have a single layer structure or a multilayer structure.

  Although it does not specifically limit as a board | substrate used by this invention, Transparent substrates, such as opaque board | substrates, such as a metal board | substrate and a ceramic board | substrate, glass, quartz, a plastic sheet, are used. It is also possible to control the color light by using a color filter film, a fluorescent color conversion filter film, a dielectric reflection film, or the like on the substrate.

  Note that a protective layer or a sealing layer can be provided on the prepared element for the purpose of preventing contact with oxygen or moisture. Examples of protective layers include diamond thin films, inorganic material films such as metal oxides and metal nitrides, polymer films such as fluororesins, polyparaxylene, polyethylene, silicone resins, and polystyrene resins, and photocurable resins. Can be mentioned. Further, it is possible to cover glass, a gas impermeable film, a metal, etc., and to package the element itself with an appropriate sealing resin.

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. In addition, the Example regarding the fluorene compound of this invention is the synthesis example 1, Example 2 3 thru | or 27, 33, 35 thru | or 37, 39, 41, 46 thru | or 50, 52, 54, 55, 59, 61 thru | or 63, 67. 70 and 73 through a through 7 5.

  <Synthesis Example 1> [Exemplary Compound No. 1] Synthesis of 1]

  In a 500 ml three-necked flask, 2.0 g (5.68 mmol) of 2,7-dibromo-9,9-dimethylfluorene [1], 4.2 g (17.0 mmol) of pyrene-1-boronic acid [2], 120 ml of toluene and 60 ml of ethanol was added, and an aqueous solution of 24 g of sodium carbonate / 120 ml of water was added dropwise with stirring in a nitrogen atmosphere at room temperature, and then 0.33 g (0.28 mmol) of tetrakis (triphenylphosphine) palladium (0) was added. After stirring at room temperature for 30 minutes, the temperature was raised to 77 degrees and stirred for 5 hours. After the reaction, the organic layer was extracted with chloroform, dried over anhydrous sodium sulfate, and purified with a silica gel column (hexane + toluene mixed developing solvent). 1 (white crystals) 3.0 g (yield 89%) was obtained.

  <Synthesis Example 2> [Exemplary Compound No. 2] Synthesis of 6]

  A 500 ml three-necked flask was charged with 3.0 g (5.49 mmol) of dibromofluorene compound [3], 4.0 g (16.5 mmol) of pyrene-1-boronic acid [2], 100 ml of toluene and 50 ml of ethanol. While stirring at room temperature, an aqueous solution of 20 g of sodium carbonate / 100 ml of water was added dropwise, and then 0.33 g (0.28 mmol) of tetrakis (triphenylphosphine) palladium (0) was added. After stirring at room temperature for 30 minutes, the temperature was raised to 77 degrees and stirred for 5 hours. After the reaction, the organic layer was extracted with chloroform, dried over anhydrous sodium sulfate, and purified with a silica gel column (hexane + toluene mixed developing solvent). 3.4 g (yield 79%) of 6 (white crystals) was obtained.

  <Synthesis Example 3> [Exemplary Compound No. Synthesis of 7]

  A 500 ml three-necked flask was charged with 3.0 g (4.07 mmol) of dibromofluorene compound [4], 3.0 g (12.2 mmol) of pyrene-1-boronic acid [2], 100 ml of toluene and 50 ml of ethanol. While stirring at room temperature, an aqueous solution of 16 g of sodium carbonate / 80 ml of water was added dropwise, and then 0.23 g (0.20 mmol) of tetrakis (triphenylphosphine) palladium (0) was added. After stirring at room temperature for 30 minutes, the temperature was raised to 77 degrees and stirred for 5 hours. After the reaction, the organic layer was extracted with chloroform, dried over anhydrous sodium sulfate, and purified with a silica gel column (hexane + toluene mixed developing solvent). 2.7 g (68% yield) of 7 (white crystals) was obtained.

  <Synthesis Example 4> [Exemplary Compound No. Synthesis of 28]

  A 500 ml three-necked flask is charged with 3.0 g (6.74 mmol) of diborate fluorene [5], 6.7 g (20.2 mmol) of 3-bromoperylene [6], 140 ml of toluene and 70 ml of ethanol at room temperature in a nitrogen atmosphere. While stirring, an aqueous solution of 26 g of sodium carbonate / 130 ml of water was added dropwise, and then 0.39 g (0.34 mmol) of tetrakis (triphenylphosphine) palladium (0) was added. After stirring at room temperature for 30 minutes, the temperature was raised to 77 degrees and stirred for 10 hours. After the reaction, the organic layer was extracted with chloroform, dried over anhydrous sodium sulfate, and purified with a silica gel column (hexane + toluene mixed developing solvent). Thus, 3.1 g (yield 66%) of 28 (white crystals) was obtained.

<Example 1>
An element having the structure shown in FIG. 2 was produced.

  What formed indium tin oxide (ITO) as an anode 2 with a film thickness of 120 nm on a glass substrate as a substrate 1 by a sputtering method was used as a transparent conductive support substrate. This was ultrasonically washed successively with acetone and isopropyl alcohol (IPA), then boiled and washed with IPA, and then dried. Furthermore, what was UV / ozone cleaned was used as a transparent conductive support substrate.

  A hole transport layer 5 was formed by depositing a chloroform solution of a compound represented by the following structural formula on a transparent conductive support substrate with a film thickness of 30 nm by spin coating.

Furthermore, Exemplified Compound No. The fluorene compound represented by 1 was formed into a film with a thickness of 50 nm by a vacuum deposition method, and the electron transport layer 6 was formed. The degree of vacuum at the time of vapor deposition was 1.0 × 10 ⁻⁴ Pa, and the film formation rate was 0.2 to 0.3 nm / sec.

Next, a metal layer film having a thickness of 50 nm is formed on the organic layer by a vacuum deposition method using a deposition material composed of aluminum and lithium (lithium concentration: 1 atomic%) as the cathode 4, and further a vacuum deposition method. Thus, an aluminum layer having a thickness of 150 nm was formed. The degree of vacuum at the time of vapor deposition was 1.0 × 10 ⁻⁴ Pa, and the film formation rate was 1.0 to 1.2 nm / sec.

  Further, a protective glass plate was placed in a nitrogen atmosphere and sealed with an acrylic resin adhesive.

When a direct current voltage of 10 V was applied to the device obtained in this manner with the ITO electrode (anode 2) as the positive electrode and the Al-Li electrode (cathode 4) as the negative electrode, a current density of 12.5 mA / cm ² was applied. And blue light emission was observed at a luminance of 8500 cd / m ² .

Further, when a voltage was applied for 100 hours with the current density kept to 10.0 mA / cm ^2, after the initial luminance 7200cd / m ² 100 hours 6800cd / m ² and luminance degradation was small.

<Examples 2 to 10>
Exemplified Compound No. A device was prepared in the same manner as in Example 1 except that the one shown in Table 1 was used instead of 1, and the same evaluation was performed. The results are shown in Table 1.

<Comparative Examples 1-3>
Exemplified Compound No. A device was prepared in the same manner as in Example 1 except that a compound represented by the following structural formula was used instead of 1, and the same evaluation was performed. The results are shown in Table 1.

<Example 11>
An element having the structure shown in FIG. 3 was prepared.

  In the same manner as in Example 1, a hole transport layer 5 was formed on a transparent conductive support substrate.

Furthermore, Exemplified Compound No. The fluorene compound represented by 2 was formed into a film with a thickness of 20 nm by a vacuum deposition method to form the light emitting layer 3. The degree of vacuum at the time of vapor deposition was 1.0 × 10 ⁻⁴ Pa, and the film formation rate was 0.2 to 0.3 nm / sec.

Furthermore, aluminum triskinolinol was formed into a film with a thickness of 40 nm by a vacuum deposition method, and the electron transport layer 6 was formed. The degree of vacuum at the time of vapor deposition was 1.0 × 10 ⁻⁴ Pa, and the film formation rate was 0.2 to 0.3 nm / sec.

  Next, the cathode 4 was formed in the same manner as in Example 1 and then sealed.

When a direct current voltage of 8 V was applied to the device thus obtained with the ITO electrode (anode 2) as the positive electrode and the Al—Li electrode (cathode 4) as the negative electrode, a current density of 12.0 mA / cm ² was applied. And blue light emission was observed at a luminance of 16000 cd / m ² .

Further, when a voltage was applied for 100 hours while maintaining the current density at 10.0 mA / cm ² , the luminance deterioration was small, from the initial luminance of 14000 cd / m ² to 13000 cd / m ² after 100 hours.

<Examples 12 to 22>
Exemplified Compound No. A device was prepared in the same manner as in Example 11 except that the materials shown in Table 2 were used in place of 7, and the same evaluation was performed. The results are shown in Table 2.

<Comparative Examples 4-6>
Exemplified Compound No. In place of the comparative compound No. 7 A device was prepared in the same manner as in Example 11 except that 1 to 3 were used, and the same evaluation was performed. The results are shown in Table 2.

<Example 23>
An element having the structure shown in FIG. 3 was prepared.

  On a transparent conductive support substrate similar to that of Example 1, a chloroform solution of a compound represented by the following structural formula was formed into a film with a thickness of 20 nm by a spin coating method to form a hole transport layer 5.

Furthermore, Exemplified Compound No. No. 1 and exemplified compound No. 1 The light-emitting layer 3 was formed by depositing an arylamine compound represented by AA-6 (weight ratio 100: 1) with a film thickness of 20 nm by a vacuum deposition method. The degree of vacuum at the time of vapor deposition was 1.0 × 10 ⁻⁴ Pa, and the film formation rate was 0.2 to 0.3 nm / sec.

Furthermore, aluminum triskinolinol was formed into a film with a thickness of 40 nm by a vacuum deposition method, and the electron transport layer 6 was formed. The degree of vacuum at the time of vapor deposition was 1.0 × 10 ⁻⁴ Pa, and the film formation rate was 0.2 to 0.3 nm / sec.

Next, the cathode 4 was formed in the same manner as in Example 1 and then sealed. When a direct current voltage of 8 V was applied to the device thus obtained with the ITO electrode (anode 2) as the positive electrode and the Al—Li electrode (cathode 4) as the negative electrode, a current density of 13.0 mA / cm ² was applied. And blue light emission was observed at a luminance of 32000 cd / m ² .

Further, when a voltage was applied for 100 hours while maintaining the current density at 10.0 mA / cm ² , the luminance deterioration was small, from the initial luminance of 25000 cd / m ² to 22000 cd / m ² after 100 hours.

<Examples 24-77>
Exemplified fluorene compound no. 1 and Exemplified Arylamine Compound No. 1 A device was prepared in the same manner as in Example 23 except that AA-6 was changed to that shown in Tables 3 to 5, and the same evaluation was performed. The results are shown in Tables 3-5.

<Comparative Examples 7-9>
Exemplified Compound No. In place of Comparative Compound No. 1 A device was prepared in the same manner as in Example 23 except that 1 to 3 were used, and the same evaluation was performed. The results are shown in Table 5.

<Example 78>
An element having the structure shown in FIG. 3 was prepared.

  On a transparent conductive support substrate similar to that of Example 1, a chloroform solution of a compound represented by the following structural formula was formed into a film with a thickness of 20 nm by a spin coating method to form a hole transport layer 5.

Furthermore, Exemplified Compound No. A fluorene compound represented by 20 and a compound represented by the following structural formula (weight ratio: 100: 5) were formed into a film with a thickness of 20 nm by a vacuum deposition method to form the light emitting layer 3. The degree of vacuum at the time of vapor deposition was 1.0 × 10 ⁻⁴ Pa, and the film formation rate was 0.2 to 0.3 nm / sec.

Further, bathophenanthroline (BPhen) was formed into a film with a thickness of 40 nm by a vacuum deposition method, and the electron transport layer 6 was formed. The degree of vacuum at the time of vapor deposition was 1.0 × 10 ⁻⁴ Pa, and the film formation rate was 0.2 to 0.3 nm / sec.

Next, the cathode 4 was formed in the same manner as in Example 1 and then sealed. When a direct current voltage of 8 V was applied to the element obtained in this manner with an ITO electrode (anode 2) as a positive electrode and an Al-Li electrode (cathode 4) as a negative electrode, a current density of 10.0 mA / cm ² was applied. And green light emission was observed at a luminance of 11000 cd / m ² .

Further, when a voltage was applied for 100 hours while keeping the current density at 7.0 mA / cm ² , the luminance deterioration was small, from the initial luminance of 8000 cd / m ² to 6500 cd / m ² after 100 hours.

<Examples 79 to 87>
Exemplified Compound No. A device was prepared in the same manner as in Example 78 except that the materials shown in Table 6 were used in place of 20, and the same evaluation was performed. The results are shown in Table 6.

<Comparative Examples 10-12>
Exemplified Compound No. In place of the comparative compound No. 20, A device was prepared in the same manner as in Example 78 except that 1 to 3 were used, and the same evaluation was performed. The results are shown in Table 6.

<Example 88>
An element having the structure shown in FIG. 1 was prepared.

  On the transparent conductive support substrate similar to Example 1, Exemplified Compound No. A film obtained by dissolving 0.050 g of the fluorene compound represented by 1 and 1.00 g of poly-N-vinylcarbazole (weight average molecular weight = 63,000) in 80 ml of chloroform is a film having a thickness of 120 nm by spin coating (rotation speed = 2000 rpm). A thick film was formed to form an organic layer (light emitting layer 3).

Next, the cathode 4 was formed in the same manner as in Example 1 and then sealed. When a direct current voltage of 10 V was applied to the device thus obtained with a positive electrode of the ITO electrode (anode 2) and a negative electrode of the Al-Li electrode (cathode 4), a current density of 8.5 mA / cm ² was applied. And blue light emission was observed at a luminance of 3200 cd / m ² .

Further, when a voltage was applied for 100 hours while maintaining the current density at 5.0 mA / cm ² in a nitrogen atmosphere, the luminance degradation was small, from the initial luminance of 2500 cd / m ² to 2100 cd / m ² after 100 hours.

<Examples 89 to 92>
Exemplified Compound No. A device was prepared in the same manner as in Example 88 except that the materials shown in Table 6 were used instead of 1, and the same evaluation was performed. The results are shown in Table 7.

<Comparative Examples 13-15>
Exemplified Compound No. In place of Comparative Compound No. 1 A device was prepared in the same manner as in Example 88 except that 1 to 3 were used, and the same evaluation was performed. The results are shown in Table 7.

It is sectional drawing which shows an example of the organic light emitting element in this invention. It is sectional drawing which shows the other example of the organic light emitting element in this invention. It is sectional drawing which shows the other example of the organic light emitting element in this invention. It is sectional drawing which shows the other example of the organic light emitting element in this invention. It is sectional drawing which shows the other example of the organic light emitting element in this invention. It is sectional drawing which shows the other example of the organic light emitting element in this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Substrate 2 Anode 3 Light emitting layer 4 Cathode 5 Hole transport layer 6 Electron transport layer 7 Hole injection layer 8 Hole / exciton blocking layer

Claims (7)

In an organic light emitting device having at least a pair of electrodes composed of an anode and a cathode, a light emitting layer composed of an organic compound sandwiched between the pair of electrodes, and a hole transport layer ,
The light emitting layer contains a fluorene compound represented by the following structural formula ,

and
The organic light-emitting device, wherein the hole transport layer comprises an aminofluorene compound represented by the following structural formula .

Before SL onset photic layer, and the fluorene compound, an organic light emitting device according to claim 1, characterized in that it contains an arylamine compound represented by the following general formula [X].

Wherein R ₁₃ and R ₁₄ represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and are different from each other. R ₁₃ mutually bonded to fluorene group, R ₁₄ to each other may be different even in the same, R ₁₃ and R ₁₄ bonding to the same fluorene group may be different even in the same .R ₁₅ and R _{16 each} represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a cyano group, or a halogen atom. each other R ₁₅ which bonded to different fluorene groups R ₁₆ may be different even in the same, R ₁₅ and R ₁₆ bonding to the same fluorene group, the same der .Ar ₃ may be different even if, Ar _4, Ar ₅ and Ar ₆ are substituted or unsubstituted aromatic group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group Alternatively, it represents a substituted or unsubstituted condensed polycyclic heterocyclic group, and Ar ₃ , Ar ₄ , Ar ₅ and Ar ₆ may be the same or different, and m represents an integer of 1 to 10. ) Before SL onset photic layer, and the fluorene compound, an organic light emitting device according to claim 1, characterized in that it contains an arylamine compound represented by the following general formula [XI].

Wherein R ₁₇ and R ₁₈ represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and are different from each other. each other R ₁₇ to bind to the fluorene group, together R ₁₈ may be different even in the same, R ₁₇ and R ₁₈ bonding to the same fluorene group may be different even in the same .R ₁₉ and R _{20 each} represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a cyano group or a halogen atom. each other R ₁₉ binding to different fluorene group, R ₂₀ to each other may be different even in the same, R ₁₉ and R ₂₀ bonding to the same fluorene group, the same der .Ar ₇ and Ar ₈ may be different even if is a divalent substituted or unsubstituted aromatic group or a substituted or unsubstituted heterocyclic group, Ar ₇ and Ar ₈ may be the same Ar ₉ , Ar ₁₀ , Ar ₁₁ and Ar ₁₂ may be substituted or unsubstituted aromatic group, substituted or unsubstituted heterocyclic group, substituted or unsubstituted condensed polycyclic aromatic group or substituted Alternatively, it represents an unsubstituted condensed polycyclic heterocyclic group, and Ar ₉ , Ar ₁₀ , Ar ₁₁ and Ar ₁₂ may be the same or different, and p represents an integer of 1 to 10. Before SL onset photic layer, and the fluorene compound, an organic light emitting device according to claim 1, characterized in that it contains an arylamine compound represented by the following general formula [XII].

Wherein R ₂₁ and R ₂₂ represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and are different from each other. each other R ₂₁ to bind to the fluorene group, together R ₂₂ may be different even in the same, R ₂₁ and R ₂₂ bonding to the same fluorene group may be different even in the same .R ₂₃ and R _{24 each} represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a cyano group, or a halogen atom. each other R ₂₃ binding to different fluorene group, R ₂₄ to each other may be different even in the same, R ₂₃ and R ₂₄ bonding to the same fluorene group, the same der Good .Ar ₁₃ and Ar ₁₄ be different even represent a substituted or unsubstituted aromatic group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group or a substituted or unsubstituted Represents a condensed polycyclic heterocyclic group, Ar ₁₃ and Ar ₁₄ may be the same or different, Ar ₁₅ represents a divalent substituted or unsubstituted aromatic group or a substituted or unsubstituted heterocyclic ring; And q represents an integer of 1 to 10.) Before SL onset photic layer, and the fluorene compound, an organic light emitting device according to claim 1, characterized in that it contains an arylamine compound represented by the following general formula [XIII].

(Wherein R ₂₅ and R ₂₆ are a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a cyano group, or R ₂₅ and R ₂₆ bonded to different phenylene groups may be the same or different, and R ₂₅ and R ₂₆ bonded to the same phenylene group may be the same or different. Ar ₁₆ and Ar ₁₇ represent a divalent substituted or unsubstituted aromatic group or a substituted or unsubstituted heterocyclic group, and Ar ₁₆ and Ar ₁₇ may be the same or different. which may .Ar _18, Ar _19, Ar ₂₀ and Ar ₂₁ are a substituted or unsubstituted aromatic group, a substituted or unsubstituted heterocyclic group, there condensed polycyclic aromatic group or substituted substituted or unsubstituted Represents an unsubstituted fused polycyclic heterocyclic _{group, Ar 18, Ar 19, Ar} 20 and Ar ₂₁ are optionally .r be different even in the same represents an integer of 1 to 10.) Before SL onset photic layer, and the fluorene compound, an organic light emitting device according to claim 1, characterized in that it contains an arylamine compound represented by the following general formula [XIV].

Wherein R ₂₇ and R ₂₈ are a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aralkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a cyano group or R ₂₇ and R ₂₈ bonded to different phenylene groups may be the same or different, and R ₂₇ and R ₂₈ bonded to the same phenylene group may be the same or different. Ar ₂₂ and Ar ₂₃ are a substituted or unsubstituted aromatic group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group, or a substituted or unsubstituted condensed polycyclic ring. represents a heterocyclic group, Ar ₂₂ and Ar ₂₃ are good .Ar ₂₂ and Ar ₂₃ be different even in the same, the mosquitoes with N which are bonded Ar ₂₂ and Ar ₂₃ bonded to each other Good .Ar ₂₄ be formed Bazoru ring, .s which represents a divalent substituted or unsubstituted aromatic group or a substituted or unsubstituted heterocyclic group represents an integer of 1 to 10.) Before SL onset photic layer, the fluorene compound, an organic light emitting device according to claim 1, characterized by containing an acetylene compound represented by the following general formula [XV].

(In the formula, Ar ₂₅ and Ar ₂₆ are a substituted or unsubstituted aromatic group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group, or a substituted or unsubstituted condensed polycyclic heterocyclic group, Represents a cyclic group, and Ar ₂₅ and Ar ₂₆ may be the same or different, and t represents an integer of 1 to 5.)

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