KR20160095667A - Pentaphenylbenzene derivative compound and organic electroluminescent device using the same - Google Patents

Abstract

The present invention relates to a pentaphenylbenzene derivative compound and an organic electroluminescent device using the same. More specifically, the present invention relates to a novel pentaphenylbenzene derivative compound which has a specific structure including pentaphenylbenzene, thereby exhibiting excellent properties such as light-emitting properties, thermal stability, luminosity with brightness, luminous efficiency, color purity, lifespan properties, and low driving voltage, when used as an organic layer such as light-emitting layers in the organic electroluminescent devices. The present invention further relates to a method for producing the same and an organic electroluminescent device using the same.

Description

TECHNICAL FIELD [0001] The present invention relates to a pentaphenylbenzene derivative compound and an organic electroluminescent device using the same. BACKGROUND ART < RTI ID = 0.0 > PENETAPHENYLBENZENE DERIVATIVE COMPOUND AND ORGANIC ELECTROLUMINESCENT DEVICE USING THE SAME &

The present invention relates to a pentaphenylbenzene derivative compound and an organic electroluminescent device using the same. More particularly, the present invention relates to a pentaphenylbenzene derivative compound having a specific structure including pentaphenylbenzene, To a novel pentaphenylbenzene derivative compound capable of realizing characteristics, thermal stability, light emission luminance, luminous efficiency, color purity and lifetime characteristics and a low driving voltage, a method for producing the same, and an organic electroluminescent device using the same.

As the movement toward the information society accelerates, interest in electronic devices using organic semiconductors is rapidly increasing in the information electronics industry. Therefore, over the last 10 years, development of organic materials having semiconductive properties overcoming the durability problems of organic materials has been actively carried out and various applications have been actively studied. The field of applied research using organic semiconductors such as electromagnetic wave shielding films, organic EL displays, organic thin film transistors, and solar cells continues to expand. Organic semiconductors are expected to be indispensable for future industries as they have the advantages of simple fabrication processes, low cost, breakable by impact, and the ability to implement devices on thin and flexible substrates such as paper. In particular, the development of organic displays capable of meeting these needs is an important research area.

Organic light emitting (EL) devices are attracting attention as color display devices that complement the disadvantages of currently used display devices. Due to their high efficiency, self-luminescence, low temperature processability, ) Display. Particularly, the driving life of the organic light emitting diode (OLED) has been largely solved, and the materials to be used have been diversified.

OLED is a structure in which an organic thin film is stacked between an anode and a cathode by using a characteristic of emitting organic light when a voltage is applied. When a voltage is applied to the electrode, holes injected from the transparent anode and electrons injected from the cathode recombine in the light emitting layer, and light corresponding to the energy gap generated at this time is generated. However, in a simple structure, efficiency becomes low due to a large energy difference between the layers to the light emitting region of holes and electrons. (HIL), a hole transport layer (HTL), an electron injection layer (EIL), and an electron transport layer (Electron Injection Layer) to obtain high efficiency and low driving voltage by generating a large number of excitons. Transfer Layer (ETL). In this case, holes and electrons that do not form excitons will have a leakage current, so a balanced injection is needed. In order to inject holes and electrons from the electrode, it is necessary to go beyond the energy barrier. Therefore, the anode uses ITO having a small work function and the cathode has a low work function metal (Ca / Al, Li: Al, Mg: Ag , LiF / Al, LiF: Al / Al, etc.) is used.

The light emitting material of the organic electroluminescent device OLED is divided into fluorescence and phosphorescence. The method of forming a light emitting layer includes a method of doping a fluorescent host with a dopant, and a method of doping a fluorescent host with a dopant, (DPVBi, Rubrene, DCJTB, etc.) to the light emitting body, and a method of moving the emission wavelength to a long wavelength. Such doping is intended to improve the emission wavelength, efficiency, driving voltage, lifetime, and the like.

Such a thin film structure formed by a vacuum evaporation method in a general organic electroluminescent device can adjust the moving speed of holes and electrons to balance the density of holes and electrons in the light emitting layer, thereby enhancing the luminous efficiency. In addition, in order to realize practical use and improve the characteristics of the organic electroluminescent device, the device material (for example, a light emitting layer material, a hole transporting material, etc.) must be thermally and electrically stable as well as constituting the device with a multilayer structure as described above. When a voltage is applied, a molecule having a low thermal stability due to heat generated in a device has a low crystal stability and is rearranged. As a result, local crystallization occurs, which causes deterioration and destruction of the device.

In short, development of a new compound capable of harmonizing various performance factors of devices such as excellent luminescence characteristics, thermal stability, light emission luminance, luminous efficiency, long life time characteristics and low driving voltage when applied to an organic material layer of an organic electroluminescent device is continuously This is a required situation.

Korean Patent Publication No. 10-2004-0003199

Disclosure of Invention Technical Problem [8] The present invention has been made to solve the problems of the prior art as described above, and it is an object of the present invention to provide an organic EL device having a high luminous brightness, luminous efficiency and thermal stability, A novel structure compound having a pentaphenylbenzene derivative as a core capable of improving the electron transport efficiency, a method of efficiently and economically synthesizing such compounds, and an organic electroluminescent device using the same.

In order to accomplish the above object, the present invention provides a pentaphenylbenzene derivative compound group having a specific structure.

Also, the pentaphenylbenzene derivative compound is used as an organic material layer material (for example, a light emitting layer material) of an organic electroluminescent device.

Specifically, the pentaphenylbenzene derivative compound is used as a host material of an organic electroluminescent device emitting layer.

In another aspect of the present invention, there is provided a process for preparing a pentaphenylbenzene derivative compound by reacting a precursor reactant substituted with I or Br with phenylacetylene, and then reacting the resultant compound with tetraphenylcyclopentadienone do.

Further, a method of reacting a precursor reactant substituted with I or Br and trimethylsilylacetylene, removing trimethylsilyl group with potassium carbonate, and then reacting the resultant compound with tetraphenylcyclopentadiene again to obtain the pentaphenylbenzene derivative compound .

According to still another aspect of the present invention, there is provided an organic electroluminescent device including a first electrode, a second electrode, and at least one organic material layer disposed between the electrodes, wherein the at least one organic material layer includes a light emitting layer, The present invention provides an organic electroluminescent device comprising the above-described pentaphenylbenzene derivative compound.

In addition, the at least one organic material layer may further include at least one layer selected from the group consisting of a hole injection layer, a hole transport layer, a hole blocking layer, an electron transport layer, and an electron injection layer.

The present invention realizes excellent luminescence characteristics and thermal / electrical stability of a device by applying a novel structure compound including a pentaphenylbenzene derivative to an organic electroluminescent device (for example, as a light emitting layer material of a multi-layered organic electroluminescent device) The light emitting efficiency, the light emission luminance, the power efficiency, the color purity, the driving voltage and the life characteristics can be greatly improved.

Specifically, the pentaphenylbenzene derivative compound according to the present invention is excellent in thermal stability with a high glass transition temperature and thermal decomposition temperature, and is suitable for the production of high performance devices. Commercialization of organic electroluminescent devices requiring high efficiency, high brightness and long life .

1 is a schematic view illustrating a single layer structure of an organic electroluminescent device according to an embodiment of the present invention.
FIG. 2 is a schematic view illustrating a multiple layer structure of an organic electroluminescent device according to another embodiment of the present invention. Referring to FIG.
3 is a graph showing UV (Ultraviolet) spectrum of the pentaphenylbenzene derivative compound 1 according to the present invention.
4 is a graph showing PL (Photoluminescence) spectrum of the pentaphenylbenzene derivative compound 1 according to the present invention.
5 is a graph showing the pyrolysis temperature of the pentaphenylbenzene derivative compound 1 according to the present invention.

Hereinafter, the present invention will be described in detail.

Pentaphenylbenzene derivative compound

The pentaphenylbenzene derivative compound according to the present invention is a novel compound having various electron donor derivatives bonded to a pentaphenylbenzene derivative having a high glass transition temperature and is selected from the group of compounds represented by the following structural formulas. The present inventors have found that when the pentaphenylbenzene derivative compound having such a specific structure is applied as an organic material layer material of an organic electroluminescent device, it realizes excellent luminescence and thermal stability of the device, lowers the driving voltage, and significantly improves the luminous efficiency, color purity and lifetime Respectively.

In a preferred embodiment, the pentaphenylbenzene derivative compound according to the present invention may be selected from the group of compounds represented by the following structural formulas.

The pentaphenylbenzene derivative compound of the present invention is used as an organic material layer material of an organic electroluminescence device, wherein the organic material layer includes an electroluminescence layer, a hole injection layer, a hole transport layer (Hole Transport Layer) (Hole Blocking Layer), an electron transport layer (Electron Transport Layer), and an electron injection layer (Electron Injection Layer).

Specifically, the pentaphenylbenzene derivative compound according to the present invention exhibits excellent luminescent characteristics and can be suitably used as a luminescent layer material of an organic electroluminescent device, more specifically, as a host material of an organic electroluminescent device luminescent layer.

In addition, the pentaphenylbenzene derivative compound according to the present invention may have various properties depending on the kind of the substituent, besides the light emitting layer material, and perform all the functions such as hole injection, hole transport, electron injection and electron transport according to the substituent And it is expected to contribute greatly to the improvement of the display industry by providing an organic electroluminescent device having high efficiency and excellent color purity.

The pentaphenylbenzene derivative of the present invention can be prepared by reacting a precursor reactant with an acetylenic compound to obtain an intermediate, and reacting it with tetraphenylcyclopentadiene to form a pentaphenylbenzene moiety.

In one embodiment, the compounds 1 to 8 are each substituted with I or Br, and have a precursor reactant necessary for the preparation of each compound, reacting it with phenylacetylene, and then reacting the obtained intermediate compound with tetraphenylcyclopentadiene Followed by final reaction.

In another embodiment, the compound 9 and the compound 10 are substituted with I or Br. The compound 9 and the compound 10 are reacted with trimethylsilylacetylene, followed by removing the trimethylsilyl group with potassium carbonate, And finally reacting the intermediate compound with tetraphenylcyclopentadienone.

3 and 4 are UV (Ultraviolet) / PL (Photoluminescence) spectra of Compound 1 prepared according to the present invention. The UV / PL spectrum is a graph measuring the emission wavelength of each compound in order to characterize the OLED, and measuring the wavelength at which light is most emitted by irradiating light of a wavelength absorbed through UV. The UV / PL spectrum can be obtained through a method known in the art. In the present invention, a solid film prepared by coating a solution containing the compound 1 in Quartz is irradiated with excitation light having a specific wavelength, .

Further, as shown in FIG. 5, the compound 1 prepared according to the present invention has a thermal decomposition temperature of about 382 ° C, which indicates excellent thermal stability.

Meanwhile, the pentaphenylbenzene derivative compound according to the present invention can be used for a flat panel display, a planar light emitting device, a light emitting device for surface emitting OLED for illumination, a flexible light emitting device, a copier, a printer, an LCD backlight, Display plate and the like and can function as a principle similar to that applied to an organic light emitting device in an organic electronic device such as an organic solar cell (OSC), an electronic paper (e-paper), an organic photoconductor (OPC) .

Organic field  Light emitting element

According to another aspect of the present invention, there is provided an organic electroluminescent device comprising the above-described pentaphenylbenzene derivative compound as an organic material layer.

The organic layer of the organic electroluminescent device of the present invention may have a single layer structure of one layer or a multilayer structure of two or more layers including a light emitting layer. Here, in the case where the organic material layer has a multilayer structure, it may be a structure in which a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and the like are stacked. That is, the organic electroluminescent device of the present invention may have the structure shown in FIG. 1 (single layer structure) and FIG. 2 (multiple layer structure), but it is not limited thereto.

Specifically, the present invention comprises a first electrode (02), a second electrode (03) formed on a substrate (01), and at least one organic layer disposed between the electrodes and at least one layer of the organic layer And an organic electroluminescent device comprising the pentaphenylbenzene derivative compound according to the present invention.

More specifically, the present invention is an organic electroluminescent device comprising a first electrode (02), a second electrode (03) formed on a substrate (01) and one or more organic layers disposed between the electrodes The organic layer includes the light emitting layer 06 and the light emitting layer 06 comprises the pentaphenylbenzene derivative compound according to the present invention. Here, the one or more organic layers may include at least one layer selected from the group consisting of a hole injection layer 04, a hole transport layer 05, a hole blocking layer (not shown), an electron transport layer 07 and an electron injection layer 08 As shown in FIG. For example, in the organic electroluminescent device of the present invention, the organic material layer includes a hole injecting layer 04, a hole transporting layer 05, a light emitting layer 06, a hole blocking layer (not shown), an electron transporting layer 07, 08, and one or two layers of a hole injection layer 04, a hole transport layer 05, a hole blocking layer (not shown), an electron transport layer 07 and an electron injection layer 08 are formed as needed Can be used in an omitted state.

The organic electroluminescent device of the present invention can be produced by a conventional method and materials for manufacturing an organic electroluminescent device, except that the above-described pentaphenylbenzene derivative compound is used to form one or more organic compound layers.

For example, the organic electroluminescent device according to the present invention may be formed by depositing a metal and a conductive material on the substrate 01 by using a known PVD (Physical Vapor Deposition) method such as sputtering or e-beam evaporation A hole transporting layer 05, a light emitting layer 06, a hole blocking layer (not shown), and an electron transporting layer 07 (not shown) are formed on the anode 02 by depositing a metal oxide or an alloy thereof. And an electron injection layer 08, and then depositing a material usable as the cathode 03 on the organic layer. An organic electroluminescent device may also be manufactured by sequentially depositing a cathode 03 material, an organic material layer, and an anode 02 material on the substrate 01. Herein, the organic material layer may be formed by using a variety of polymer materials, but not by evaporation, but by using a solvent process such as spin coating, dip coating, doctor blading, screen printing, inkjet printing, Can also be produced.

As the anode material, a material having a large work function is preferably used so that hole injection can be smoothly conducted into the organic material layer. Specifically, metals such as vanadium, chromium, copper, zinc, and gold, or alloys thereof; Metal oxides such as zinc oxide, indium oxide, indium tin oxide (ITO), titanium oxide (TiO), and indium zinc oxide (IZO); ZnO: Al or SnO _2: a combination of a metal and an oxide such as Sb; A conductive polymer such as poly (3-methylthiophene), poly [3,4- (ethylene-1,2-dioxy) thiophene] (PEDT), polypyrrole and polyaniline may be used, no.

As the negative electrode material, a material having a small work function is preferably used to facilitate electron injection into the organic material layer. Specifically, metals such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin and lead or alloys thereof; Layer structure materials such as LiAl and LiF / Al or LiO2 / Al, but the present invention is not limited thereto.

As the hole injection layer material, it is preferable that HOMO (Highest Occupied Molecular Orbital) of the hole injection layer material be between the work function of the anode material and the HOMO of the surrounding organic layer . It is also preferable to use a material having a surface adhesion with the anode and a planarizing ability capable of alleviating the surface roughness of the anode. Materials having HOMO and LUMO (Lowest Unoccupied Molecular Orbital) values larger than the band gap of the light emitting layer and materials having high chemical stability and thermal stability are preferable. Specifically, the hole injection layer material may include at least one selected from the group consisting of metal porphyrin, oligothiophene, arylamine-based organic materials, hexanitrile hexaazatriphenylene-based organic materials, quinacridone- Perylene based organic materials, anthraquinone, polyaniline and polythiophene-based conductive polymers, but the present invention is not limited thereto.

As the hole transport layer material, a material capable of transporting holes from the anode or the hole injection layer to the light emitting layer is preferable. Materials having HOMO and LUMO values larger than the band gap of the light emitting layer and materials having high chemical stability and thermal stability are preferable. Specifically, an arylamine-based organic material, a conductive polymer, and a block copolymer having a conjugated portion and a non-conjugated portion together may be used, but the present invention is not limited thereto.

The light emitting layer material is a material capable of emitting light in the visible light region by transporting holes and electrons from the hole transporting layer and the electron transporting layer, respectively. In the present invention, the pentaphenylbenzene derivative compound as described above is used as the light emitting layer material.

In one preferred embodiment, the light emitting layer in the organic electroluminescent device of the present invention may be dopant doped with the pentaphenylbenzene derivative compound as a host material. In the case of single emission, efficiency and brightness are very low, and the molecules are brought close to each other, so that excimer characteristics other than the intrinsic characteristics of each molecule can be exhibited. As a result, a dopant material is doped on a host material It is preferable to use one light-emitting layer. When the dopant material is doped on the host material, the energy generated by the excited electrons in the host material returning to the base state is absorbed by the dopant material, and the dopant material returns to the base state and emits light. For example, Firpic, Ir (piq) ₃ , Ir (phq) ₂ (acac), Ir (ppy) ₃ and the like can be used as the dopant.

As the hole blocking layer material, a material larger than the HOMO value of the light emitting layer is preferable. Materials having high chemical stability and thermal stability are also desirable. Specifically, TPBi and BCP are mainly used, and CBP, PBD, PTCBI, and BPhen may be used, but the present invention is not limited thereto.

As the electron transport layer and the electron injection layer material, a material capable of injecting electrons from the cathode well and transferring the electrons to the light emitting layer is preferable. Materials with high chemical stability and thermal stability are also suitable. Specifically, Al complex of 8-hydroxyquinoline; Complexes containing Alq ₃ ; Organic radical compounds; Hydroxyflavone-metal complex, and the like may be used, but the present invention is not limited thereto.

The organic electroluminescent device according to the present invention may be a front emission type, a back emission type, or a both-sided emission type, depending on the material used.

Hereinafter, the present invention will be described more specifically by way of Synthesis Examples and Examples. However, these synthesis examples and examples are provided only for the understanding of the present invention, and the scope of the present invention is not limited to these examples in any sense.

Synthesis Example 1: Preparation of compound 1

<Step 1>

A dried round flask was charged with 1 eq. Of 4-iododeneimide iophene (10 g, 32.2 mmol), 0.02 eq of bis (triphenylphosphine) palladium (II) dichloride (0.45 g, 0.644 mmol) mmol) and 0.2 eq of triphenylphosphine (1.69 g, 6.44 mmol) were charged, and nitrogen was sufficiently charged after the decompression. Triethylamine (120 ml) was added and the temperature was raised while stirring. 1.1 eq of phenylacetylene (3.9 ml, 35.4 mmol) was slowly added dropwise at 50 &lt; 0 &gt; C. Followed by stirring at 80 ° C for 24 hours.

The reaction mixture was cooled to room temperature and extracted with dichloromethane and distilled water. The organic layer was dried over anhydrous magnesium sulfate and filtered. The filtered organic layer was concentrated under reduced pressure, and the obtained mixture was purified by column chromatography with dichloromethane / hexane to obtain Compound A (8.3 g, 91%).

<Step 2>

In a dried round flask, 1 eq of the compound A (3 g, 10.5 mmol) obtained in <Step 1> was added with 1.05 eq of tetraphenylcyclopentadienone (4.25 g, 11.07 mmol), and after the decompression, nitrogen was sufficiently charged. Diethyl ether (70 ml) was added, and the mixture was stirred at 225 占 폚 for 24 hours.

Then, the mixture was cooled to room temperature, ethanol was added thereto, and the mixture was stirred for 1 hour or longer. The mixture was filtered, and the powder in the upper layer was washed with alcohol and recrystallized from dichloromethane / ethanol to obtain Compound 1 (4 g, 60%).

FD-MS: m / z = 640.42 (C ₄₈ H ₃₂ S = 640.22)

Synthesis Example 2: Preparation of Compound 2

Compound 2 was prepared in the same manner as in Synthesis Example 1, except that in Step 1, the 2-iododobenzimidophene was used instead of the 4-iododobenzimidophene.

FD-MS: m / z = 639.86 (C ₄₈ H ₃₂ S = 640.22)

Synthesis Example 3: Preparation of Compound 3

<Step 1>

To a dried round flask was added 1 eq of 3,6-diiodo-9-phenylcarbazole (10 g, 20.2 mmol), 0.05 eq of bis (triphenylphosphine) palladium (II) dichloride (0.71 g, 1 mmol) (0.38 g, 2 mmol) and 0.1 eq of triphenylphosphine (0.53 g, 2 mmol) were charged, and after the pressure was reduced, nitrogen was sufficiently charged. Triethylamine (130 ml) and benzene (60 ml) were added and the temperature was raised while stirring. At 50 &lt; 0 &gt; C, 2.2 eq of phenylacetylene (4.87 ml, 44.43 mmol) was slowly added dropwise. Followed by stirring at 80 ° C for 24 hours.

The reaction mixture was cooled to room temperature and extracted with dichloromethane and distilled water. The organic layer was dried over anhydrous magnesium sulfate and filtered. The filtrated organic layer was concentrated under reduced pressure, and the obtained mixture was purified by column chromatography with dichloromethane / hexane to obtain Compound C (8.4 g, 85%).

<Step 2>

To a dried round flask was added 1 eq of the compound C (3 g, 6.7 mmol) obtained in <Step 1> together with 2.1 eq of tetraphenylcyclopentadienone (5.46 g, 14.2 mmol), and the pressure was reduced to sufficiently fill with nitrogen. Diethyl ether (100 ml) was added, and the mixture was stirred at 225 占 폚 for 24 hours.

Then, the mixture was cooled to room temperature, ethanol was added thereto, and the mixture was stirred for 1 hour or longer. The mixture was filtered, and the powder in the upper layer was washed with alcohol and recrystallized from dichloromethane / ethanol to obtain Compound 3 (4.4 g, 56%).

FD-MS: m / z = 1156.01 (C ₉₀ H ₆₁ N = 1155.48)

Synthesis Example 4: Preparation of Compound 4

Compound 4 was prepared in the same manner except that 9,10-bis (4-bromophenyl) anthracene was used instead of 3,6-diiodo-9-phenylcarbazole in Step 1 of Synthesis Example 3 Respectively.

FD-MS: m / z = 1243.23 (C ₉₈ H ₆₆ = 1242.52)

Synthesis Example 5: Preparation of Compound 5

<Step 1>

0.5 eq of potassium iodide (0.22 g, 1.32 mmol) and potassium iodate (0.28 g, 1.32 mmol) were added to a dried round flask, followed by stirring at room temperature for 1 hour. eq, and the mixture was stirred at 100 ° C for 24 hours. Then, the mixture was cooled to room temperature, and water and sodium thiosulfate were added thereto. The mixture was stirred for 1 hour or longer. The mixture was filtered, and the powder in the upper layer was washed with alcohol and recrystallized from dichloromethane / ethanol to obtain Compound F (1 g, 55%).

<Steps 2 and 3>

Compound 5 was prepared in the same manner except that the compound F was used in place of the 4-iododobenzyldiophene in < Step 1 > in Synthesis Example 1.

FD-MS: m / z = 1017.11 (C ₇₈ H ₅₂ N ₂ = 1016.41)

Synthesis Example 6: Preparation of Compound 6

Compound 6 was prepared in the same manner except that Compound H was used in place of 3,6-diiodo-9-phenylcarbazole in Step 1 of Synthesis Example 3.

FD-MS: m / z = 1397.88 (C ₁₀₈ H ₇₂ N ₂ = 1396.57)

Synthesis Example 7: Preparation of Compound 7

Compound 4 was prepared in the same manner except that Compound J was used in place of 4-iododobenzyliodophene in < Step 1 > in Synthesis Example 1.

FD-MS: m / z = 882.12 (C ₆₆ H ₄₃ NS = 881.31)

Synthesis Example 8: Preparation of Compound 8

Compound 8 was prepared in the same manner except that the compound L was used instead of the 4-iododobenzoyldiophene in < Step 1 > in Synthesis Example 1.

FD-MS: m / z = 882.44 (C ₆₆ H ₄₃ NS = 881.31)

Synthesis Example 9: Preparation of Compound 9

In Step 1 of Synthesis Example 1, trimethylsilyl acetylene was used instead of phenylacetylene, and trimethylsilyl group was removed with potassium carbonate to prepare Compound O. Compound 9 was prepared in the same manner except for the above two.

FD-MS: m / z = 565.70 (C ₄₂ H ₂₈ S = 564.74)

Synthesis Example 10: Preparation of Compound 10

Compound Q was prepared by using trimethylsilylacetylene in place of phenylacetylene in Step 1 of Synthesis Example 4 and removing trimethylsilyl group with potassium carbonate. Compound 10 was prepared in the same manner except for the above two.

FD-MS: m / z = 1092.01 (C ₈₆ H ₅₈ = 1091.38)

Example 1: Fabrication of organic electroluminescent device

Before the deposition for the device fabrication, a glass substrate coated with a thin film of ITO (Indium Tin Oxide) at a thickness of 1500Å was cleaned (impurities and fine particles on the surface were deformed by organic substances, deterioration of interfacial properties between ITO and organic materials, A phenomenon in which light is not partially or totally caused due to burning of impurities at the time of contact, defective contact with ITO, and shortening of the lifetime of the device). In order to remove impurities such as organic substances, ionic substances, and metallic substances present on the substrate before the organic material deposition, the substrate was removed by ultrasonic cleaning for 5 minutes at room temperature with acetone, and then 5 parts by IPA (Isopropyl alcohol) Ultrasonic cleaning was performed for a minute and then dried using N ₂ gas.

HAT-CN, a hole injecting layer, was vacuum deposited on the prepared ITO transparent electrode to a thickness of 100 Å and a hole transporting material NPB was vacuum deposited thereon to a thickness of 400 Å. Then, Firpic (10%) was added to the compound 1 obtained in Synthesis Example 1 And BmPyPb was vacuum deposited as an electron transport layer to a thickness of 300 Å. Lithium fluoride (LiF) having a thickness of 5 Å and aluminum having a thickness of 1200 Å were sequentially deposited to form a cathode. Here, the deposition rate of the organic material was 1 Å / sec, the deposition rate of lithium fluoride was 0.1 Å / sec, and the deposition rate of aluminum was 1 Å / sec.

The characteristics of the thus-fabricated organic electroluminescent device at a current density of 10 mA / cm ² , such as driving voltage, luminescence brightness, and luminous efficiency, are shown in Table 1 below.

Example 2: Fabrication of organic electroluminescent device

An organic electroluminescent device was prepared in the same manner as in Example 1, except that Compound 2 obtained in Synthesis Example 2 was used instead of Compound 1 as a light emitting layer material.

The characteristics of the organic electroluminescent device at a current density of 10 mA / cm ² , such as driving voltage, luminescence brightness, and luminous efficiency, are shown in Table 1 below.

Example 3: Fabrication of organic electroluminescent device

An organic electroluminescent device was prepared in the same manner as in Example 1, except that Compound 3 obtained in Synthesis Example 3 was used instead of Compound 1 as a light emitting layer material.

The characteristics of the organic electroluminescent device at a current density of 10 mA / cm ² , such as driving voltage, luminescence brightness, and luminous efficiency, are shown in Table 1 below.

Example 4: Fabrication of organic electroluminescent device

An organic electroluminescent device was prepared in the same manner as in Example 1, except that Compound 4 obtained in Synthesis Example 4 was used instead of Compound 1 as a light emitting layer material.

The characteristics of the organic electroluminescent device at a current density of 10 mA / cm ² , such as driving voltage, luminescence brightness, and luminous efficiency, are shown in Table 1 below.

Example 5: Fabrication of organic electroluminescent device

An organic electroluminescent device was prepared in the same manner as in Example 1, except that Compound 5 obtained in Synthesis Example 5 was used instead of Compound 1 as the light emitting layer material.

The characteristics of the organic electroluminescent device at a current density of 10 mA / cm ² , such as driving voltage, luminescence brightness, and luminous efficiency, are shown in Table 1 below.

Example 6: Fabrication of organic electroluminescent device

An organic electroluminescent device was fabricated in the same manner as in Example 1, except that Compound 6 obtained in Synthesis Example 6 was used instead of Compound 1 as a light emitting layer material.

The characteristics of the organic electroluminescent device at a current density of 10 mA / cm ² , such as driving voltage, luminescence brightness, and luminous efficiency, are shown in Table 1 below.

Example 7: Fabrication of organic electroluminescent device

An organic electroluminescent device was prepared in the same manner as in Example 1, except that Compound 7 obtained in Synthesis Example 7 was used instead of Compound 1 as a light emitting layer material.

The characteristics of the organic electroluminescent device at a current density of 10 mA / cm ² , such as driving voltage, luminescence brightness, and luminous efficiency, are shown in Table 1 below.

Example 8: Fabrication of organic electroluminescent device

An organic electroluminescent device was prepared in the same manner as in Example 1, except that Compound 8 obtained in Synthesis Example 8 was used instead of Compound 1 as a light emitting layer material.

The characteristics of the organic electroluminescent device at a current density of 10 mA / cm ² , such as driving voltage, luminescence brightness, and luminous efficiency, are shown in Table 1 below.

Example 9: Fabrication of organic electroluminescent device

An organic electroluminescent device was prepared in the same manner as in Example 1, except that Compound 9 obtained in Synthesis Example 9 was used instead of Compound 1 as the light emitting layer material.

The characteristics of the organic electroluminescent device at a current density of 10 mA / cm ² , such as driving voltage, luminescence brightness, and luminous efficiency, are shown in Table 1 below.

Comparative Example 1: Fabrication of organic electroluminescent device

(Carbazole-9-yl) biphenyl (CBP) represented by the following chemical formula was used instead of Compound 1 as the light emitting layer material, an organic electroluminescent device was fabricated in the same manner as in Example 1.

The characteristics of the organic electroluminescent device at a current density of 10 mA / cm ² , such as driving voltage, luminescence brightness, and luminous efficiency, are shown in Table 1 below.

[Table 1]

As shown in Table 1, when the pentaphenylbenzene derivative compound according to the present invention is used, an organic electroluminescent device with low voltage, high efficiency, and high brightness based on its excellent hole transporting and electron transporting ability can be manufactured, and excellent thermal stability is also obtained .

01: substrate
02: anode (or first electrode)
03: cathode (or second electrode)
04: Hole injection layer
05: Hole transport layer
06: light emitting layer
07: Electron transport layer
08: Electron injection layer

Claims (9)

A pentaphenylbenzene derivative compound selected from the group of compounds represented by the structural formula:

.
The method according to claim 1,
Wherein the pentaphenylbenzene derivative compound is selected from the group of compounds represented by the following structural formulas:

.
The method according to claim 1,
Wherein the pentaphenylbenzene derivative compound is used as an organic material layer material of an organic electroluminescent device.
The method of claim 3,
Wherein the pentaphenylbenzene derivative compound is used as a light emitting layer material of an organic electroluminescent device.
5. The method of claim 4,
Wherein the pentaphenylbenzene derivative compound is used as a host material of the light emitting layer of the organic electroluminescent device.
I or Br is reacted with phenylacetylene and then the obtained compound is reacted with tetraphenylcyclopentadiene again to prepare a pentaphenylbenzene derivative compound of any of Compounds 1 to 8 according to Claim 2 How to.
I or Br is reacted with trimethylsilylacetylene, the trimethylsilyl group is removed with potassium carbonate, and the obtained compound is further reacted with tetraphenylcyclopentadienone to obtain the compound 9 according to the second aspect or the penta Phenylbenzene derivative compound.
1. An organic electroluminescent device comprising a first electrode, a second electrode, and at least one organic material layer disposed between the electrodes,
Wherein the one or more organic layers include a light emitting layer,
Wherein the light emitting layer comprises the pentaphenylbenzene derivative compound according to any one of claims 1 to 5.
9. The method of claim 8,
Wherein the at least one organic material layer further comprises at least one layer selected from the group consisting of a hole injection layer, a hole transport layer, a hole blocking layer, an electron transport layer, and an electron injection layer.

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