JP5072896B2 - Diazafluorene compound, organic light-emitting device and organic light-emitting device using the same - Google Patents

Description

  The present invention relates to a novel organic compound and an organic light-emitting device using the same.

  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 1987, Kodak Research (Non-patent Document 1) used ITO for the anode and magnesium-silver alloy for the cathode, an aluminum quinolinol complex as the electron transport material and the light emitting material, and a triphenylamine derivative as the hole transport material. The device having the function-separated type two-layer structure used has been reported to emit about 1000 cd / m ^{2 at} an applied voltage of about 10V. Examples of related patents include Patent Documents 1 to 3 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, it describes in patent documents 4-11.

  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 reports that an organic light emitting device using an iridium complex as a light emitting material exhibits high luminous efficiency (Non-Patent Document 2).

  Furthermore, in addition to the organic light-emitting device using the low-molecular material as described above, an organic light-emitting device using a conjugated polymer has been reported by a group of Cambridge University (Non-Patent Document 3). In this report, light emission was confirmed in a single layer by forming a film of polyphenylene vinylene (PPV) in a coating system.

  Patents 12 to 16 and the like can be cited as related patents of organic light emitting devices using conjugated polymers.

  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.

  On the other hand, phenanthroline compounds, oxadiazole compounds, or triazole compounds are known as electron transport materials. Examples of using these compounds in organic light-emitting devices include Patent Documents 17 to 19, but the characteristics when used as an electron transport layer or a light-emitting layer are not sufficient.

US Pat. No. 4,539,507 U.S. Pat. No. 4,720,432 US Pat. No. 4,885,211 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 JP-A-9-202878 JP-A-9-227576 US Pat. No. 5,247,190 US Pat. No. 5,514,878 US Pat. No. 5,672,678 JP-A-4-145192 Japanese Patent Application Laid-Open No. 5-247460 JP-A-5-331459 JP-A-4-363891 JP 7-41759 A

Appl. Phys. Lett. 51,913 (1987) Nature, 395, 151 (1998) Nature, 347, 539 (1990)

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

  Another object of the present invention is to provide an organic light-emitting device using a specific diazafluorene compound and having a light output with extremely high efficiency and high luminance.

  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.

（式中、Ｒ₁₃およびＲ₁₄は、置換あるいは無置換の縮合多環芳香族基または置換あるいは無置換の縮合多環複素環基を表わし、同じであっても異なっていてもよい。
Ｒ₁₅およびＲ₁₆は、水素原子、置換あるいは無置換のアルキル基、置換あるいは無置換のアリール基または置換あるいは無置換の複素環基を表わし、同じであっても異なっていてもよい。
前記縮合多環複素環基は次のいずれかである：
カルバゾリル基、フェナントロリル基、アクリジニル基。
前記複素環基は次のいずれかである：
チエニル基、ピロリル基、ピリジル基、オキサゾリル基、オキサジアゾリル基、チアゾリル基、チアジアゾリル基、ターチエニル基。）

That is, the diazafluorene compound of the present invention is characterized by being represented by the following general formulas [I] to [III] (except for the following compound No. 2) . In addition, the compound shown by the following general formula [IV] corresponds to this invention among the compounds shown by the general formula [I]-[III] mentioned later.

(Wherein R ₁₃ and R ₁₄ represent a substituted or unsubstituted condensed polycyclic aromatic group or a substituted or unsubstituted condensed polycyclic heterocyclic group, and may be the same or different.
R ₁₅ and R ₁₆ represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group, and may be the same or different.
The fused polycyclic heterocyclic group is any of the following:
A carbazolyl group, a phenanthroyl group, an acridinyl group.
The heterocyclic group is any of the following:
Thienyl group, pyrrolyl group, pyridyl group, oxazolyl group, oxadiazolyl group, thiazolyl group, thiadiazolyl group, tertenyl group; )

Wherein R ₁ and R ₂ are a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group Represents a substituted or unsubstituted condensed polycyclic heterocyclic group, a substituted amino group, a cyano group or a halogen atom, and may be the same or different, and R ₃ and R ₄ may be a hydrogen atom, substituted or unsubstituted. Represents an alkyl group, a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, and R ₃ and R ₄ bonded to different fluorene groups may be the same or different. R ₃ and R ₄ bonded to the fluorene group may be the same or different.
n represents an integer of 1 to 10. )

Wherein R ₅ and R ₆ are a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group Represents a substituted or unsubstituted condensed polycyclic heterocyclic group, a substituted amino group, a cyano group or a halogen atom, and may be the same or different, and R ₇ and R ₈ may be a hydrogen atom, substituted or unsubstituted. The alkyl group, the substituted or unsubstituted aryl group or the substituted or unsubstituted heterocyclic group, which may be the same or different.

Wherein R ₉ and R ₁₀ are a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group Represents a substituted or unsubstituted condensed polycyclic heterocyclic group, a substituted amino group, a cyano group or a halogen atom, which may be the same or different.
R ₁₁ and R ₁₂ represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group, and may be the same or different. )

  The organic light-emitting device of the present invention is an organic light-emitting device having at least a layer containing a pair of electrodes composed of an anode and a cathode, and one or a plurality of organic compounds sandwiched between the pair of electrodes. At least one of the containing layers contains at least one of the diazafluorene compounds.

The organic light-emitting device using the diazafluorene compound of the present invention can emit light with high luminance at a low applied voltage and has excellent durability. In particular, the organic layer containing the diazafluorene 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.

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.

  Hereinafter, the present invention will be described in detail.

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

  The diazafluorene compound of the present invention is represented by the above general formulas [I] to [III], and the diazafluorene compound represented by the general formula [I] is a compound represented by the following general formula [IV] Is preferred.

(Wherein R ₁₃ and R ₁₄ represent a substituted or unsubstituted condensed polycyclic aromatic group or a substituted or unsubstituted condensed polycyclic heterocyclic group, and may be the same or different.
R ₁₅ and R ₁₆ represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group, and may be the same or different. )

In the diazafluorene compounds represented by the general formulas [I] to [III], R ₁ , R ₂ , R ₅ , R ₆ , R ₉ , R ₁₀ , R ₁₃ or R ₁₄ is represented by the following general formula [V]. It is preferable that it is a condensed polycyclic aromatic group shown by any of-[X].

(Wherein R ₁₇ represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a substituted amino group, a cyano group or a halogen atom. R ₁₈ And R ₁₉ represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group or a substituted or unsubstituted heterocyclic group, which may be the same or different.

Wherein R _{20 to} R ₂₃ represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a substituted amino group, a cyano group or a halogen atom. .)

Wherein R ₂₄ and R ₂₅ represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a substituted amino group, a cyano group or a halogen atom. , May be the same or different.)

  Specific examples of the substituents in the general formulas [I] to [X] 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 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 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, a phenanthroyl group, and an acridinyl 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 substituent that the substituent may have include an alkyl group such as a methyl group, an ethyl group, and a propyl group, an aryl group such as a phenyl group and a biphenyl group, a heterocyclic group such as a thienyl group, a pyrrolyl group, and a pyridyl group. , Amino groups such as dimethylamino group, diethylamino group, dibenzylamino group, diphenylamino group, ditolylamino group, dianisolylamino group, alkoxyl groups such as methoxyl group, ethoxyl group, propoxyl group, phenoxyl group, cyano group , Halogen atoms such as fluorine, chlorine, bromine and iodine.

Next, typical examples of the diazafluorene compound of the present invention will be given below, but the present invention is not limited thereto. Of the representative examples described below, Exemplified Compound No. 1 , no. 3 to No. 21, no. 24 corresponds to the present invention.

  The diazafluorene compound of the present invention can be synthesized by a generally known method. Am. Chem. Soc. 106, 5876-5879 (1984), J. Am. Org. Chem. , 50, 666-670, (1985), J. Am. Org. Chem. , 49, 2208-2212 (1984) and the like, and a diazafluorene compound intermediate is obtained, and a Suzuki coupling method using a palladium catalyst (for example, Chem. Rev. 1995, 95, 2457-2483) is used. It can be obtained by a synthesis method.

  The diazafluorene compound of the present invention is a compound having excellent electron transport properties 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 or a solution coating method is hardly crystallized and has excellent stability over time.

  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 diazafluorene compound represented by the general formulas [I] to [III].

  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 diazafluorene compounds.

  In the organic light emitting device of the present invention, the diazafluorene compound represented by the above general formulas [I] to [III] 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.

  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 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. It 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 diazafluorene compounds represented by the general formulas [I] to [III] used in the present invention are compounds having excellent electron transport properties and durability as compared with conventional compounds, and any of the forms shown in FIGS. But it can be used.

  In the present invention, the diazafluorene compound represented by the general formulas [I] to [III] is used as a constituent component of the electron transport layer or the light-emitting layer. A compound, an electron transporting compound, or the like can be used together as necessary.

  Examples of these compounds are given below.

  In the organic light-emitting device of the present invention, the layer containing the diazafluorene compound represented by the general formulas [I] to [III] and the layer containing another organic compound are generally prepared by a vacuum deposition method or an appropriate solvent. Dissolve to form a thin film by a coating method. 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. Among the examples described below, Synthesis Example 1, Example 1-6, 11-18, 26, 28-30, 41, 42, and 44 to 48 correspond to the present invention.

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

  In a 200 ml three-necked flask, 10.0 g (55.0 mmol) of 4,5-diazafluoren-9-one [1] and 13.4 ml (80%, 220 mmol) of hydrazine monohydrate were added, and the mixture was heated at 160 ° C. for 12 hours. After stirring, water was added, the organic layer was extracted with chloroform, dried over anhydrous sodium sulfate, and then purified with an alumina column (chloroform developing solvent) to obtain 4.8 g (52% yield) of [2] (white crystals). It was.

  Next, 3.0 g (17.8 mmol) of [2] and 70 ml of DMF were placed in a 200 ml three-necked flask, and 2.1 g (39.2 mmol) of sodium methoxide was added with stirring at 0 ° C. in a nitrogen atmosphere. 4.4 ml (71.2 mmol) of methyl chloride was added dropwise. After stirring at room temperature for 12 hours, water was added, and the organic layer was extracted with chloroform, dried over anhydrous sodium sulfate, and then purified with an alumina column (chloroform developing solvent) to obtain 2.8 g of [3] (white crystals) (yield 80 %).

  Further, 5.9 g (18.3 mmol) of 2-iodo-9,9-dimethylfluorene [4] and 50 ml of diethyl ether were placed in a 200 ml three-necked flask, and n-butyllithium was stirred at −78 ° C. in a nitrogen atmosphere. (15% hexane solution) 11.9 ml (18.3 mmol) was added dropwise. After raising the temperature to room temperature and stirring for 1 hour, the mixture was cooled to −20 ° C. and [3] 1.0 g (5.10 mmol) of toluene in 80 ml was added dropwise. After stirring at room temperature for 12 hours, water was added, the organic layer was extracted with chloroform, dried over anhydrous sodium sulfate, and purified with an alumina column (hexane + chloroform mixed developing solvent). 1.6 g (yield 54%) of 1 (yellow crystal) was obtained.

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

  [3] 3.0 g (15.3 mmol) and nitrobenzene 70 ml were placed in a 200 ml three-necked flask, and a solution of bromine 2.4 ml (45.9 mmol) in nitrobenzene 10 ml was added dropwise at 130 ° C. with stirring at 140 ° C. for 5 hours. Stir. The reaction solution was added dropwise to water, and the organic layer was extracted with chloroform, washed with an aqueous sodium thiosulfate solution, dried over anhydrous sodium sulfate, purified with an alumina column (hexane + chloroform mixed developing solvent), and the dibromo compound [5] ( 1.8 g (yield 33%) of white crystals) was obtained.

  Next, a dibromo compound [5] 0.5 g (1.41 mmol), boronic acid [6] 1.3 g (5.65 mmol), toluene 60 ml and ethanol 30 ml were placed in a 200 ml three-necked flask, and at room temperature in a nitrogen atmosphere. Under stirring, an aqueous solution of 6 g of sodium carbonate / 30 ml of water was added dropwise, and then 0.16 g (0.14 mmol) of tetrakis (triphenylphosphine) palladium (0) was added. After stirring at room temperature for 30 minutes, the temperature was raised to 77 ° C. and stirred for 3 hours. After the reaction, the organic layer was extracted with chloroform, dried over anhydrous sodium sulfate, and purified with an alumina column (chloroform developing solvent). 2 (yellow crystal) 0.7g (yield 85%) was obtained.

<Synthesis Example 3> [Exemplary Compound No. Synthesis of 41]

[7] ^*) 3.0 g (11.1 mmol) and DMF 70 ml were placed in a 200 ml three-necked flask, and 1.3 g (24.4 mmol) of sodium methoxide was added with stirring at 0 ° C. in a nitrogen atmosphere. Methyl 2.1 ml (33.3 mmol) was added dropwise. After stirring at room temperature for 12 hours, water was added, and the organic layer was extracted with chloroform, dried over anhydrous sodium sulfate, and purified with an alumina column (chloroform developing solvent), and 2.5 g of [8] (yellow crystals) (yield 76). %).

  Further, 3.9 g (12.1 mmol) of 2-iodo-9,9-dimethylfluorene [4] and 50 ml of diethyl ether were placed in a 200 ml three-necked flask, and n-butyllithium was stirred at −78 ° C. in a nitrogen atmosphere. 7.8 ml (12.1 mmol) (15% hexane solution) was added dropwise. After warming to room temperature and stirring for 1 hour, it cooled to -20 degreeC and the 80 ml toluene dispersion liquid of [8] 1.0g (3.36 mmol) was dripped. After stirring at room temperature for 12 hours, water was added, the organic layer was extracted with chloroform, dried over anhydrous sodium sulfate, and purified with an alumina column (hexane + chloroform mixed developing solvent). Thus, 1.1 g (yield 48%) of 41 (yellow crystals) was obtained.

<Example 1>
An element having the structure shown in FIG. 3 was prepared.

  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, Ir complexes represented by the following structural formulas and Exemplified Compound Nos. The diazafluorene compound (weight ratio 5: 100) shown by No. 1 was formed into a film with a film thickness of 20 nm by a vacuum evaporation method, and the light emitting layer 3 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.

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, 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 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 21.0 mA / cm ² was applied. And green light emission was observed at a luminance of 6000 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 2000 cd / m ² to 1500 cd / m ² after 100 hours.

<Examples 2 to 10>
Exemplified Compound No. A device was prepared in the same manner as in Example 1 except that the exemplified compounds shown in Table 1 were used in place 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, arylamino compounds represented by the following structural formulas and exemplified compound Nos. The diazafluorene compound (polymerization ratio 1:20) shown by 4 was formed into a film with a film thickness of 20 nm by a vacuum evaporation method, and the light emitting layer 3 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.

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 6V DC voltage 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, the current flowed at a current density of 120 mA / cm ^2. A blue light emission was observed at a luminance of 9500 cd / m ² .

Further, when a voltage was applied for 100 hours while maintaining the current density at 100 mA / cm ² , the luminance deterioration was small, from an initial luminance of 7500 cd / m ² to 6000 cd / m ² after 100 hours.

<Examples 12 to 25>
Exemplified Compound No. A device was prepared in the same manner as in Example 11 except that the exemplified compounds shown in Table 2 were used in place of 4, and the same evaluation was performed. The results are shown in Table 2.

<Comparative Examples 4-6>
Exemplified Compound No. In place of Comparative Compound No. 4 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 26>
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, coumarin and aluminum triskinolinol (polymerization ratio 1:20) were formed into a film with a thickness of 20 nm by a vacuum evaporation method, and the light emitting layer 3 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.

Furthermore, Exemplified Compound No. The diazafluorene compound shown by 1 was formed into a film with a film thickness of 40 nm, and the electron carrying 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 6V DC voltage 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 was applied at a current density of 190 mA / cm ^2. And emission of green light was observed at a luminance of 17000 cd / m ² .

Further, when a voltage was applied for 100 hours while maintaining the current density at 150 mA / cm ² , the luminance deterioration was small, from the initial luminance of 8000 cd / m ² to 6000 cd / m ² after 100 hours.

<Examples 27 to 40>
Exemplified Compound No. A device was prepared in the same manner as in Example 26 except that the exemplified compounds shown in Table 3 were used instead of 1, and the same evaluation was performed. The results are shown in Table 3.

<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 26 except that 1 to 3 were used, and the same evaluation was performed. The results are shown in Table 3.

<Example 41>
An element having the structure shown in FIG. 3 was prepared.

On the same transparent conductive support substrate as in Example 1, an arylamine compound represented by the following structural formula was formed into a film with a thickness of 40 nm by a vacuum deposition method to form a hole transport layer 5. 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, an Ir complex represented by the following structural formula and a carbazole compound (polymerization ratio 5: 100) represented by the following structural formula were formed into a film with a thickness of 20 nm by a vacuum deposition method, whereby the light emitting layer 3 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.

Furthermore, Exemplified Compound No. The diazafluorene compound represented by No. 11 was formed to a thickness of 40 nm to form the electron transport layer 6. 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 10 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 24.0 mA / cm ² was applied. And green light emission was observed at a luminance of 9000 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 3500 cd / m ² to 2500 cd / m ² after 100 hours.

<Examples 42 to 55>
Exemplified Compound No. A device was prepared in the same manner as in Example 41 except that the exemplified compounds shown in Table 4 were used in place of 11, and the same evaluation was performed. The results are shown in Table 4.

<Comparative Examples 10-12>
Exemplified Compound No. In place of Comparative compound No. 11 A device was prepared in the same manner as in Example 41 except that 1 to 3 were used, and the same evaluation was performed. The results are shown in Table 4.

<Example 56>
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 solution prepared by dissolving 0.050 g of the diazafluorene compound represented by 25 and 1.00 g of poly-N-vinylcarbazole (weight average molecular weight = 63,000) in 80 ml of chloroform was spin-coated to 120 nm by a spin coating method (rotation speed = 2000 rpm). The organic layer (light emitting layer 3) was formed.

  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 1500 cd / m ² .

Furthermore, when a voltage was applied for 100 hours while maintaining the current density at 8.0 mA / cm ² in a nitrogen atmosphere, the luminance degradation was small, from the initial luminance of 1300 cd / m ² to 1100 cd / m ² after 100 hours.

<Examples 57 to 60>
Exemplified Compound No. A device was prepared in the same manner as in Example 56 except that the exemplified compounds shown in Table 5 were used instead of 25, and the same evaluation was performed. The results are shown in Table 5.

<Comparative Examples 13-15>
Exemplified Compound No. In place of the comparative compound No. 25, A device was prepared in the same manner as in Example 56 except that 1 to 3 were used, and the same evaluation was performed. The results are shown in Table 5.

  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)

A diazafluorene compound represented by the following general formula [IV] (excluding the following compound No. 2) .

(Wherein R ₁₃ and R ₁₄ represent a substituted or unsubstituted condensed polycyclic aromatic group or a substituted or unsubstituted condensed polycyclic heterocyclic group, and may be the same or different.
R ₁₅ and R ₁₆ represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group, and may be the same or different.
The fused polycyclic heterocyclic group is any of the following:
A carbazolyl group, a phenanthroyl group, an acridinyl group.
The heterocyclic group is any of the following:
Thienyl group, pyrrolyl group, pyridyl group, oxazolyl group, oxadiazolyl group, thiazolyl group, thiadiazolyl group, tertenyl group; )

2. The diazafluorene compound according to claim 1, wherein R ₁₃ or R ₁₄ is a condensed polycyclic aromatic group represented by any one of the following general formulas [V] to [X].

(Wherein R ₁₇ represents a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a substituted amino group, a cyano group, or a halogen atom.
The heterocyclic group is any of the following:
Thienyl group, pyrrolyl group, pyridyl group, oxazolyl group, oxadiazolyl group, thiazolyl group, thiadiazolyl group, tertenyl group;
R ₁₈ and R ₁₉ represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, or a substituted or unsubstituted heterocyclic group, and may be the same or different.
The heterocyclic group is any of the following:
Thienyl group, pyrrolyl group, pyridyl group, oxazolyl group, oxadiazolyl group, thiazolyl group, thiadiazolyl group, tertenyl group; )

Wherein R _{20 to} R ₂₃ represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a substituted amino group, a cyano group or a halogen atom. .
The heterocyclic group is any of the following:
Thienyl group, pyrrolyl group, pyridyl group, oxazolyl group, oxadiazolyl group, thiazolyl group, thiadiazolyl group, tertenyl group; )

Wherein R ₂₄ and R ₂₅ represent a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a substituted amino group, a cyano group or a halogen atom. , May be the same or different.
The heterocyclic group is any of the following:
Thienyl group, pyrrolyl group, pyridyl group, oxazolyl group, oxadiazolyl group, thiazolyl group, thiadiazolyl group, tertenyl group; ) It is shown by a following formula, The diazafluorene compound of Claim 1 or 2 characterized by the above-mentioned.

In the organic light emitting device having at least one layer including an anode and a cathode, and at least one layer including one or more organic compounds sandwiched between the pair of electrodes, at least one of the layers including the organic compound is defined in claim 1. 3. An organic light-emitting device comprising at least one diazafluorene compound according to any one of 3 above.   5. The organic light-emitting device according to claim 4, wherein at least an electron transport layer or a light-emitting layer among the layers containing the organic compound contains at least one of the diazafluorene compounds. An organic light emitting device having a substrate and the organic light emitting element according to claim 4,
The organic light-emitting device, wherein the substrate is an opaque substrate. An organic light emitting device having a substrate and the organic light emitting element according to claim 4,
The organic light-emitting device, wherein the substrate is a transparent substrate.

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