JP4035499B2 - Organic light emitting device - 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 for the electron transport material and the light emitting material, and a triphenylamine derivative for the hole transport material. It has been reported that light emission of about 1000 cd / m ^{2 at} an applied voltage of about 10 V has been reported with an element having a function separation type two-layer structure. 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, cyclophane compounds are used as charge transport materials and luminescent materials that are excellent in terms of their specific structural characteristics by modifying charge transport substituents and luminescent substituents. Examples of using a cyclophane compound for an organic light-emitting device include Patent Documents 17 to 21 and the like, but an orthocyclophane compound is used for an organic light-emitting device, and characteristics when used as a light-emitting layer material or a charge transport material Is not enough.

US Pat. No. 4,539,507 US 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 2001-196180 A JP 2001-294957 A JP 2001-351785 A JP 2002-173488 A JP 2002-196375 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 specific metacyclophane compound.

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

  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.

The organic light-emitting device of the present invention is a layer containing an organic compound in an organic light-emitting device having at least a pair of electrodes composed of an anode and a cathode, and a layer containing one or a plurality of organic compounds sandwiched between the pair of electrodes. At least one layer contains at least one metacyclophane compound represented by the following general formula [I].

(In the formula, R ₁ to R ₄ is a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, substituted or unsubstituted unsubstituted fused polycyclic aromatic group, a substituted or unsubstituted fused polycyclic heterocyclic group, a substituted amino group, a substituted alkenyl group, a substituted boryl group, at least one of R ₁ or R ₂ is a substituted or unsubstituted An aryl group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group, a substituted or unsubstituted condensed polycyclic heterocyclic group, a substituted amino group, a substituted alkenyl group, or a substituted boryl group R _{1 to} R ₄ may be the same or different, and n represents an integer of 2 to 4.)

In the metacyclophane compound of the present invention, each of R ₁ and R ₂ is a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group, or It is preferably a substituted or unsubstituted condensed polycyclic heterocyclic group.

  The organic light-emitting device using the metacyclophane 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 metacyclophane compound of the present invention is excellent as a charge 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.

  Specific examples of the substituent in the general formula [I] 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 alkoxyl group include a methoxyl group, an ethoxyl group, a propoxyl group, and a phenoxyl group.

  Examples of the heterocyclic group include thienyl group, pyrrolyl group, pyridyl group, bipyridyl 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 substituted alkenyl group include a propenyl group, a butenyl group, and a pentenyl group.

  Examples of the substituted boryl group include a diphenylboryl group, a ditolylboryl group, and a dimesitylboryl 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 thereof include alkoxyl groups such as phenoxyl group, boryl groups such as diphenylboryl group, ditolylboryl group and dimesitylboryl group, cyano groups, halogen atoms such as fluorine, chlorine, bromine and iodine.

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

  The metacyclophane compound of the present invention can be synthesized by a generally known method. Tsuge et al. , Chem. , Express, 7, 469-472 (1992), 2) T .; Yamato et al. , J .; Org. Chem. 57, 395-396 (1992), 3) T .; Yamato et al. , J .; Org. Chem. , 57, 271-275 (1992), etc., a metacyclophane compound intermediate can be obtained. Further, a metacyclophane compound can be obtained by a synthesis method such as Suzuki Coupling method using a palladium catalyst (for example, Chem. Rev. 1995, 95, 2457.).

  The metacyclophane compound of the present invention is a compound having excellent charge transportability and durability compared to conventional compounds, and is useful for a layer containing an organic compound of an organic light emitting device, and also includes a vacuum deposition method, a solution coating method, etc. The layer formed by the method is less susceptible to crystallization 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 metacyclophane compound of the present invention represented by the general formula [I].

  In the organic light emitting device of the present invention, the metacyclophane 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.

  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 it has a single hole transport ability, electron transport ability, and light-emitting performance, or when a compound having each characteristic is mixed.

  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 luminescent material is either a hole transporting or electron transporting material, or a material having both functions is used for each layer, and it is used in combination with a mere hole transporting material or electron transporting material that does not emit light Useful for. 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 separation of carrier transport and light emission functions. It is used in combination with compounds having hole transport properties, electron transport properties, and light emission properties in a timely manner. Since various compounds having different values can be used, it is possible to diversify the emission hue. 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 structure in which a hole injection layer 7 is inserted on the anode 2 side with respect to FIG. 3, which is effective in improving the adhesion between the anode 2 and the hole transport layer 5 or improving the hole injection property, and is effective in lowering the voltage. Is.

  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 / exciton blocking layer 8) that prevents holes or excitons (excitons) from passing to the cathode 4 side as compared with FIG. 3 and FIG. It is the structure inserted between 6. By using a compound having a very high ionization potential as the hole / exciton blocking layer 8, the structure is effective in improving the light emission efficiency.

  However, FIGS. 1 to 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 interference layer, and the hole transporting layer are composed of two layers having different ionization potentials can be employed.

  The metacyclophane compound of the present invention is a compound having excellent charge transportability and durability as compared with conventional compounds, and can be used in any form of FIGS. In addition, when the organic layer using the metacyclophane of the present invention is formed by a vacuum deposition method or a solution coating method, crystallization hardly occurs and the stability over time is excellent.

  The organic light-emitting device of the present invention uses a metacyclophane compound represented by the general formula [I] as a constituent component of the organic layer, and has heretofore been known hole transporting compounds, luminescent compounds, or electron transports. Sexual compounds and 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 metacyclophane compound represented by the general formula [I] and the layer containing another organic compound are generally applied by vacuum evaporation or dissolved in an appropriate solvent. A thin film is formed by the 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 resin. , Phenol resin, epoxy resin, silicone resin, polysulfone resin, urea resin and the like, 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, a material having a work function as large as possible is good. For example, simple metals such as gold, platinum, nickel, palladium, cobalt, selenium, vanadium or alloys thereof, tin oxide, zinc oxide, indium tin oxide (ITO), A metal oxide 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. . 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 the protective layer include diamond thin films, inorganic material films such as metal oxides and metal nitrides, polymer films such as fluorine resin, polyparaxylene, polyethylene, silicone resin, polystyrene resin, and photo-curing resins. It is done. 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.

<Example 1> [Exemplary Compound No. 1] Synthesis of 2]
In a 500 ml ^three- necked flask, metacyclophane compound [1] ^{* 1) * 2) * 3)} 1.0 g (2.73 mmol), 1-pyreneboronic acid [2] 2.0 g (8.19 mmol), toluene 100 ml and ethanol An aqueous solution of 10 g of sodium carbonate / 50 ml of water was added dropwise with stirring at room temperature in a nitrogen atmosphere, 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 degrees and stirred for 3 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 (white crystals) 1.08 g (yield 65%) was obtained.

* 1) Chem. Express, 7, 469-472 (1992)
* 2) J.A. Org. Chem. , 57, 395-396 (1992)
* 3) J. et al. Org. Chem. , 57, 271-275 (1992)

<Example 2> [Exemplary Compound No. Synthesis of 6]
In a 500 ml three-necked flask, 1.0 g (2.73 mmol) of metacyclophane compound [1], 3.5 g (8.19 mmol) of fluorene boronic acid compound [2], 100 ml of toluene and 50 ml of ethanol were placed in a nitrogen atmosphere at room temperature. Under stirring, an aqueous solution of 10 g of sodium carbonate / 50 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 degrees and stirred for 3 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). 1.6 g (yield 60%) of 6 (white crystals) was obtained.

<Example 3>
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.

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 to 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, Exemplified Compound No. 7 was used to form an electron transport layer 6 having a thickness of 40 nm. 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 the ITO electrode (anode 2) as the positive electrode and the Al-Li electrode (cathode 4) as the negative electrode, a current density of 20.0 mA / cm ² was applied. And green light emission was observed with a luminance of 5300 cd / m ² .

Further, when a voltage was applied for 100 hours while keeping the current density at 6.0 mA / cm ² , the luminance degradation was small, 1010 cd / m ² after 100 hours from the initial luminance of 1200 d / m ² .

<Examples 4 to 8>
Exemplified Compound No. A device was prepared in the same manner as in Example 3 except that the exemplified compounds shown in Table 1 were used in place of 7, and the same evaluation was performed. The results are shown in Table 1.

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

<Example 9>
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. 1 was used to form a light emitting layer 3 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, the phenanthroline compound shown by the following structural formula was formed into a film with a film thickness of 40 nm by the vacuum evaporation method, 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, in the same manner as in Example 3, a cathode 4 was formed and sealed with a protective glass plate.

When a 10V 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, the current flowed at a current density of 250 mA / cm ^2. A blue light emission was observed at a luminance of 10,000 cd / m ² .

Further, when a voltage was applied for 100 hours while keeping the current density at 200 mA / cm ² , the luminance deterioration was small, from the initial luminance of 9000 cd / m ² to 6000 cd / m ² after 100 hours.

<Examples 10 to 13>
Exemplified Compound No. A device was prepared in the same manner as in Example 9 except that the exemplified compounds shown in Table 2 were used in place of 1, and the same evaluation was performed. The results are shown in Table 2.

<Comparative Examples 3-4>
Exemplified Compound No. In place of Comparative Compound No. 1 A device was prepared in the same manner as in Example 9 except that 3 and 4 were used, and the same evaluation was performed. The results are shown in Table 2.

<Example 14>
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.

Further, Coumarin 6 and Exemplified Compound No. 2 (polymerization ratio 1:20) was formed into a film with a thickness of 20 nm by a vacuum evaporation 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, an electron transport layer 6 was formed in the same manner as in Example 9.

  Next, in the same manner as in Example 3, a cathode 4 was formed and sealed with a protective glass plate.

When a 10V 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 generated at a current density of 1000 mA / cm ^2. And emission of green light was observed at a luminance of 60000 cd / m ² .

Further, when a voltage was applied for 100 hours while maintaining the current density at 200 mA / cm ² , the luminance deterioration was small, from an initial luminance of 10,000 cd / m ² to 8400 cd / m ² after 100 hours.

<Examples 15 to 22>
Exemplified Compound No. A device was prepared in the same manner as in Example 14 except that the exemplified compounds shown in Table 3 were used instead of 2, and the same evaluation was performed. The results are shown in Table 3.

<Comparative Examples 5-6>
Exemplified Compound No. In place of Comparative Compound No. 2 A device was prepared in the same manner as in Example 14 except that 3 and 4 were used, and the same evaluation was performed. The results are shown in Table 3.

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 (2)

In an organic light-emitting element having at least one layer including an anode and a cathode and a layer including one or more organic compounds sandwiched between the pair of electrodes, at least one of the layers including the organic compound has the following general formula [ the organic light emitting device characterized in that it contains at least one indicated by I] Rume data cyclophane compounds.

(In the formula, R ₁ to R ₄ is a hydrogen atom, a substituted or unsubstituted alkyl group, a substituted or unsubstituted alkoxy group, a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, substituted or unsubstituted unsubstituted fused polycyclic aromatic group, a substituted or unsubstituted fused polycyclic heterocyclic group, a substituted amino group, a substituted alkenyl group, a substituted boryl group, at least one of R ₁ or R ₂ is a substituted or unsubstituted An aryl group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group, a substituted or unsubstituted condensed polycyclic heterocyclic group, a substituted amino group, a substituted alkenyl group, or a substituted boryl group R _{1 to} R ₄ may be the same or different, and n represents an integer of 2 to 4.) Each of R ₁ and R ₂ is a substituted or unsubstituted aryl group, a substituted or unsubstituted heterocyclic group, a substituted or unsubstituted condensed polycyclic aromatic group, or a substituted or unsubstituted condensed polycyclic heterocycle. The organic light-emitting device according to claim 1, wherein the organic light-emitting device is a cyclic group.

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