TWI492941B - Electron transporting compounds and organic electroluminescent devices using the same - Google Patents

Description

Electron transport compound and organic electroluminescent device using the same

The present invention relates to a compound comprising a benzothiophene group attached to a fluoranthene molecular skeleton and an organic electroluminescent device using the same, and in particular to a substituted or unsubstituted dibenzothiophene direct linking substituent Or a compound which does not substitute benzofluoranthene and an organic electroluminescent device using the same.

In order to cater to the application of organic electroluminescent elements, the development of novel organic luminescent materials has gradually attracted attention. The reason for the commercial production of these components is that the high-density pixel display has a manufacturing cost advantage, and the display has the advantages of long life, high brightness, low driving voltage, wide color gamut and the like.

A typical organic electroluminescent device wherein at least one organic light-emitting layer is included between the anode and the cathode. When the current is turned on, the anode is injected into the hole, and the cathode injects electrons into the organic layer. The injected holes and electrons migrate toward the opposite polarity electrodes. When an electron and a hole are localized to the same molecule, an electron-hole pair that is in an excited state and is localized to the same molecule forms an exciton. Excitons emit light through a luminescent mechanism. In order to improve this The charge transfer capability and the luminous efficiency of the components are increased outside the light-emitting layer such as an electron transport layer and/or a hole transport layer, an electron blocking layer, and/or a hole blocking layer. Various literatures have revealed that doping other materials (i.e., guest materials) into the host material of the luminescent layer enhances the performance of such elements and adjusts the chromatogram. Several types of organic electroluminescent materials and element structures disclosed in U.S. Patent Nos. 769,292, issued to U.S. Pat.

The reason why the organic electroluminescent device is fabricated by a multilayer film structure includes the stability between the interface between the electrode layer and the organic layer. In addition, in organic materials, the mobility of electrons and holes is significantly different, and accordingly, if an appropriate hole transport layer and electron transport layer are selected, holes and electrons can be efficiently transferred to the light-emitting layer. If the density of holes and electrons is balanced in the light-emitting layer, the luminous efficiency of such elements can also be improved. Properly combining the above organic layers can improve luminous efficiency and service life. However, it is very difficult to find an organic material that satisfies the various requirements of the actual display application described above.

Tris (8-hydroxyquinoline) aluminum (Alq3) is a widely used electron transport material, however, it has the properties of strong green light and high driving voltage. Therefore, the key is to find an electron transport material that is superior to conventional materials in various implementations, such as high efficiency, low driving voltage, and operational stability.

Organic small molecules with imidazole groups, oxazole groups and thiazole groups are often reported as materials for electron injection and transport layers, such as Chemical Materials Journal 2004. No. 16, p. 4556 (Chem.Mater.2004, No. 16, p. 4556).

U.S. Patent No. 5,645, 948 issued to U.S. Patent No. 5, 645, 948 issued to U.S. Pat. Tris(1-phenyl-1H-benzimidazol-2-yl)benzene, referred to as TPBI). At the 1,3,5 substitution position of the phenyl ring, TPBI has three N-phenyl benzimidazole groups, which serve as materials for electron transport and luminescence functions. However, TPBI has low operational stability.

U.S. Patent No. 6,878, 469 discloses a compound wherein a 2-phenyl benzimidazolyl group is attached to the positions of C-2 and C-6 in the molecular structure of anthracene. An electron transporting material comprising an imidazopyridyl group or a benzimidazolyl group in a molecular skeleton structure, which exhibits a low driving voltage and high efficiency, is disclosed in US Patent No. 20080125593 and Japanese Patent No. 20100007143. . However, the operational stability of these materials is also low.

Fluoranthene derivatives are luminescent compounds commonly used in the art, and are disclosed in Japanese Patent No. 2002069044, Japanese Patent No. 2005320286, Japanese Patent No. 20050243411, WO2008059713, WO2011052186, US Pat. The fused ring fluoranthene is in the electron injecting and electron transporting layer. However, these components do not have all of the properties required for electroluminescent light, namely high illumination, stable operation and low drive voltage.

Dibenzothiophenes (DBT), classified as chalcogenophenes, are inexpensive and commercially available and have been reported to be one of the most abundant compounds in LPG. Dibenzothiophene has a high dissociation energy and a broad band gap, and does not exhibit strong absorption in the visible region. The co-planarity of dibenzothiophenes facilitates intermolecular interactions. Korean Patent No. 20110085784 discloses benzodithiophenes applied to light-emitting elements. U.S. Patent No. 20120187381 discloses the use of azadibenzo moieties as an electron transporting material which still requires further improvement in stability and driving voltage.

In order to solve the above problems, there is still a need to develop a compound applied to an organic electroluminescent device.

An object of the present invention is to provide a compound and an organic electroluminescent device which are applied to an electron transport layer or a light-emitting layer of an organic electroluminescent device, so that the device has high luminous efficiency, long service life and low driving voltage. .

To achieve the above object, the present invention provides a benzothiophene attached to a fluoranthene molecular skeleton having the following formula I: Wherein X and Y independently represent an aromatic hydrocarbon or a hetero aromatic hydrocarbon having 5 to 10 carbon atoms; and Ar ₁ to Ar ₇ each independently represent 4 to 12 carbon atoms. Unsubstituted or substituted aromatic hydrocarbon or unsubstituted or substituted condensed polycyclic aromatic hydrocarbon having 4 to 12 carbon atoms, or Ar ₁ to Ar ₇ An annulated or fused aromatic ring system is formed with the adjacent aromatic hydrocarbon as needed.

In a specific embodiment, the compound has a structure selected from the group consisting of Formulas II through XIII:

Wherein X and Y independently represent an aromatic hydrocarbon or a heteroaromatic hydrocarbon having 5 to 10 carbon atoms, and R ₁ to R ₇ are independently selected from hydrogen, deuterium, alkyl, A group consisting of an alkoxy, an amino group, a silyl group, a cyano group, an aryl group, and a heteroaryl group.

In one embodiment, the X and Y lines are selected from the group consisting of phenyl, 2-tolyl, 3-tolyl, 4-tolyl, 4 a group consisting of 4-pyridyl, 1-naphthyl and 2-naphthyl.

The invention further provides a process for the manufacture of a compound selected from the group consisting of Formulas II through XIII.

In one embodiment, the compound is used to form an amorphous film for use in an organic electroluminescent device by vacuum deposition or spin coating.

The present invention further provides an organic electroluminescent device which is a compound represented by the structure of the group consisting of Formulas II to XIII.

In one embodiment, the compound is used as an electron transport layer or an electron injection layer in a single material or a combination of n-type dopant materials.

In one embodiment, the compound is used as a material for one of the light-emitting layer, the hole barrier layer, or the electron blocking layer.

In a specific embodiment, the above compound is used as a material in the light-emitting layer and is used in combination with a fluorescent or phosphorescent emitter.

In one embodiment, the organic electroluminescent device is a fluorescent organic electroluminescent device or a phosphorescent organic electroluminescent device.

The organic electroluminescent device of the present invention has high luminous efficiency, low driving voltage, long service life and better thermal stability. Further, by using the organic compound of the present invention, a high-performance white organic electroluminescent device can be produced.

100, 200, 300‧‧‧ Organic electroluminescent components

110, 210, 310‧‧‧ base

120, 220, 320‧‧‧ anode

130, 230, 330‧‧‧ hole injection layer

140, 240, 340‧‧‧ hole transport layer

150, 250, 350‧‧ ‧ luminescent layer

160, 260, 360‧‧‧ electron transport layer

170, 270, 370‧‧‧ electron injection layer

180, 280, 380‧‧‧ cathode

245, 355‧‧ ‧ exciton blocking layer

The object, spirit and advantages of the preferred embodiments of the present invention will be more apparent from the description and appended claims.

1 is a schematic cross-sectional view showing a specific embodiment of an organic electroluminescence device of the present invention; FIG. 2 is a schematic cross-sectional view showing a specific embodiment of the organic electroluminescence device of the present invention; and FIG. 3 is an organic electroluminescence of the present invention. a schematic cross-sectional view of one embodiment DETAILED DESCRIPTION element; FIG. 4 A1-based hydrogen nuclear magnetic resonance spectrum of the compound ⁽¹ H-NMR spectrum); nuclear magnetic resonance spectra of compound A2 of FIG. 55 system; FIG. 6 compound A5 The nuclear magnetic resonance spectrum is shown in Fig. 7; the electroluminescence spectrum of the organic electroluminescent device of the present invention; and Fig. 8 is a comparison of the luminance and current density of the organic electroluminescent device of the present invention.

The invention is illustrated in detail below by means of specific examples. Other advantages and effects based on the disclosure of the present specification will be apparent to those of ordinary skill in the art.

According to the present invention, the compound applied to the organic electroluminescent device is as shown in Formula I. Preferably, the compound of formula I is a compound of formula II to XIII.

In the formulae II to XIII, X and Y independently represent an aromatic hydrocarbon or a heteroaromatic hydrocarbon having 5 to 10 carbon atoms; X and Y may be the same or different; and X and Y may be selected from a phenyl group, a tolyl group, and a pyridine group. a group consisting of a base and a naphthyl group. R ₁ to R ₇ are independently selected from the group consisting of hydrogen, hydrazine, alkyl, alkoxy, amino, methoxyalkyl, cyano, aryl and heteroaryl.

Among the compounds of the above formulae II to XIII, preferred examples are the following formulas A1-A24; B1-B24; C1-C24; D1-D24; E1-E24; F1-F24; G1-G24; H1-H24. , but not limited to this.

Various arylated fluoranthene derivatives can be prepared by the methods described in the following literature, Journal of American Society, 1949, Vol. 71 (6), p1917; Journal of Nanoscience and Nanotechnology (Journal of Nanoscience and Nanotechnology) 2008, Vol. 8 (9), p. 4787.

The preparation of various dibenzothiophene derivatives can be referred to the methods described in the following references.

A typical synthetic route for the exemplified compound A2 is shown below.

In one embodiment of the invention, the above-described compounds of formula I of the invention are applicable to organic layers of organic electroluminescent devices. Accordingly, the organic light-emitting element of the present invention has at least one organic layer disposed between the anode and the cathode on the substrate, wherein the organic layer comprises the compound of formula I. Hereby stated The organic layer may be a light emitting layer, a hole blocking layer, an electron transporting layer, an electron injecting layer or a hole transporting layer. The organic layer comprising the compound of formula I is preferably an electron transport/injection layer and is combined with an electrically implantable dopant (n/p type).

The electrically conductive dopant (i.e., n/p type) for the electron transport layer is preferably an organic alkali/alkaline metal complexes, an oxide, a halide, a carbonate, and at least An alkali metal/alkaline earth metal phosphate selected from the group consisting of lithium and ruthenium. The organometallic complex can be selected from the above patents or other known suitable organometallic complexes and can be used in the present invention.

The content of the foregoing electrical implant dopant in the electron transport layer/electron injection layer is preferably between 25% by weight and 75% by weight.

The compound of the formula I can also be used for the layer between the light-emitting layer and the electron transport layer. The luminescent layer can comprise a fluorescent dopant and a phosphorescent dopant and a fluorescent and phosphorescent emitter corresponding to the fluorescent or phosphorescent dopant.

Further, the compounds of the formulae I to XIII can be used for the electron injecting/transporting layer or the hole blocking layer and/or the electron blocking layer.

The structure of the organic electroluminescent device of the present invention will be described with reference to the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a schematic cross-sectional view showing one embodiment of an organic electroluminescent device of the present invention. The organic electroluminescent device 100 includes a substrate 110, an anode 120, a hole injection layer 130, a hole transport layer 140, a light emitting layer 150, an electron transport layer 160, an electron injection layer 170, and a cathode 180. The organic electroluminescent device 100 can be fabricated by sequentially depositing the above layers. Figure 2 is the hair A schematic cross-sectional view of another embodiment of the organic electroluminescent device of the present invention. The organic electroluminescent device shown in FIG. 2 is similar to FIG. 1, except that an exciton block layer 245 is provided between the hole transport layer 240 and the light-emitting layer 250. Figure 3 is a schematic cross-sectional view showing another embodiment of the organic electroluminescent device of the present invention. The organic electroluminescence element shown in FIG. 3 is also similar to FIG. 1, except that the exciton blocking layer 355 is provided between the light-emitting layer 350 and the electron-transport layer 360.

Materials for the hole injection layer, the hole transport layer, the electron blocking layer, the hole blocking layer, the light emitting layer, and the electron injecting layer may be selected from conventional materials. For example, an electron transporting material forming an electron transporting layer is different from a material forming a light emitting layer, and has a property of transporting a hole, thereby facilitating migration of a hole in the electron transporting layer, and preventing dissociation energy from the light emitting layer and the electron transporting layer. The accumulation of carriers caused by the difference.

In addition, U.S. Patent No. 5,844,363 discloses a flexible transparent substrate incorporating an anode. No. 20030230980 as disclosed by U.S. Patent No., p-type doped hole transport layer of the system in molar ratio of 50: 1 to m-MTDATA doped with F ₄ -TCNQ. The n-doped electron transport layer is doped with Li by a molar ratio of 1:1 at BPhen, as disclosed in U.S. Patent No. 2,030,230,980. The cathode disclosed in U.S. Patent Nos. 5, 703, 436 and 5, 707, 745, the cathode having a thin metal layer, such as magnesium/silver (Mg: Ag), and a transparent conductive layer (ITO layer) covering the metal thin layer by sputtering. The application and principles of the various barrier layers disclosed in U.S. Patent Nos. 6,097,147 and 2,030, 030, 980 are incorporated herein by reference. An example of an injection layer is provided by U.S. Patent No. 2,040,174,116. A description of the protective layer is also found in U.S. Patent No. 2,040,174,116.

Structures and materials not specifically described are also applicable to the present invention, such as organic light-emitting diodes (OLEDs) composed of a polymer material (PLED) as disclosed in U.S. Patent No. 5,247,190. Further, an organic light-emitting diode having a single organic layer or an organic light-emitting diode formed by stacking disclosed in U.S. Patent No. 5,707,745 can be applied to the present invention.

Unless otherwise stated, any of the various embodiments may be deposited using any suitable method. In the case of the organic layer, the preferred method comprises the thermal evaporation method and the printing method disclosed in U.S. Patent Nos. 6,037,982 and 6,087,196; and the organic vapor phase deposition (OVPD) disclosed in U.S. Patent No. 6,337,102 The disclosure by organic vapor jet printing (OVJP) is disclosed in U.S. Patent No. 10/233,470. Other suitable methods include spin coating and solution processing. The preferred solution process is carried out in a nitrogen or inert atmosphere. For other layers, the preferred method involves thermal evaporation. The preferred method of patterning comprises a process of mask deposition and re-cold soldering as disclosed in U.S. Patent Nos. 6,294, 398 and 6, 468, 819, and a method of printing or organic vapor-jet deposition using a pattern. Of course, other methods are also applicable. The above materials can be modified to be compatible with the deposition methods they are used for.

The organic electroluminescent device of the present invention can be applied to a single component, and its structure is an element of an array configuration or an element having an anode and a cathode in an X-Y coordinate of the array. Compared with the conventional components, the present invention can significantly improve the luminous efficiency and driving stability of the organic electroluminescent device, especially in combination with the phosphorescent dopant in the light-emitting layer, and the organic electroluminescent device of the present invention can be applied to full color or The performance of the colorful display panel is good.

The following is explained in detail by way of examples, but the invention is not limited thereto.

Synthesis Example 1 (Synthesis of Compound A1)

Take 6 g of 3-bromo-7,12-diphenylbenzo[k]fluoranthene and 3.2 g of 4-dibenzothiophenyl Boronic acid was placed in 30 ml of toluene and stirred. 0.06 g of tetrakis(triphenylphosphine)palladium, 6.0 g of potassium carbonate and 15 ml of an aqueous ethanol solution were added, and the mixture was refluxed under nitrogen for 6 hours. The reaction was quenched with water and the toluene layer was removed through a celite column.

The organic layer was combined and evaporated to dryness to give a bright yellow solid product Compound A1.

Compound A1 had a melting point of 307 ° C and a glass transition temperature (Tg) of 176 ° C.

The main ultraviolet absorption peak wavelength of the compound A1 was 313 nm, 394 nm and 417 nm.

The photoluminescence spectrum of Compound A1 showed an emission wavelength of 435 nm.

The nuclear magnetic resonance spectrum of Compound A1 is shown in Figure 4.

¹ H NMR (CDCl ₃ , δ): 8.21 (dd, 1H) - 8.20 (dd, 1H); 7.72-7.57 (m, 14H); 7.56-7.54 (m, 3H); 7.48 (d, 1H); - 7.41 (m, 3H); 7.27-7.23 (m, 1H); 6.74 (d, 1H); 6.65 (d, 1H).

Synthesis Example 2 (Synthesis of Compound A2)

Take 10 g of 2-bromo-dibenzo[b,d]thiophene, 5.1 g of phenylboronic acid, 2.2 g of tetrakis(triphenylphosphine)palladium and 18.38 Potassium carbonate was placed in a mixture of 110 ml of toluene, 20 ml of ethanol and 90 ml of water to reflux overnight. The reaction was quenched with water, and the toluene layer was removed through a diatomaceous earth column to evaporate the toluene layer on a rotary evaporator to obtain 5.2 g of 2-phenyldibenzo[b,d]thiophene (2-phenyl-dibenzo[b,d ]thiophene). Under a nitrogen atmosphere, 5.2 g of 2-phenyldibenzo[b,d]thiophene was dissolved in 50 ml of anhydrous tetrahydrofuran, and the solution was cooled to -78 °C. 20.0 ml of n-butyl lithium (n-butyl lithium 1.6 M solution) was added dropwise to the reaction mixture, and stirring was continued until the temperature was equilibrated with room temperature. The reaction mixture was again cooled to -60 ° C, and 5.67 mL of trimethyl borate was added and stirring was continued until overnight. The reaction was quenched with 20% aqueous hydrochloric acid and the organic layer was extracted with ethyl acetate. The ethyl acetate layer was washed with water and dried over anhydrous sodium sulfate. 8-phenyldibenzo[b,d]thiophene-4-boronic acid.

4.63 g of 3-bromo-7,12-diphenylbenzo[k]fluoranthene prepared by a conventional method and 3.5 g of 8-phenyldibenzo[b,d]thiophene-4-boronic acid were placed in 50 ml. Mix in toluene with stirring. 0.553 g of tetrakis(triphenylphosphine)palladium, 4.62 g of potassium carbonate and 50 ml of an aqueous ethanol solution were added, and the mixture was refluxed with nitrogen. Supervised by thin layer chromatography Control the reaction process for 6 hours. The reaction was quenched with water, further extracted with water and chromatographed to afford toluene. The organic layers were combined and evaporated to dryness on a rotary evaporator.

Compound A2 did not exhibit an observable melting point. The visible light-ultraviolet absorption peak wavelength of the compound A2 is at 395 nm and 417 nm, and the photoluminescence spectrum of the photoluminescence spectrum exhibited in tetrahydrofuran is 440 nm.

The nuclear magnetic resonance spectrum of Compound A2 is shown in Figure 5.

¹ H NMR (CDCl ₃ , δ): 8.45-8.39 (m, 1H); 8.25 (dd, 1H); 7.83-7.56 (m, 17H); 7.51-7.36 (m, 8H); 7.27-7.24 (m, 1H); 6.73 (d, 1H); 6.63 (d, 1H).

Synthesis Example 3 (Synthesis of Compound A5)

Take 14 g of 2,8-dibromo-dibenzo[b,d]thiophene, 11.0 g of phenylboronic acid, 3.8 g of tetrakis(triphenylphosphine)palladium and 20 g of potassium carbonate in 110 ml of toluene and 20 ml of ethanol ( A mixture of 20 mL) and 90 mL of water (90 mL) was refluxed overnight. The reaction was quenched with water, and the toluene layer was removed through a diatomaceous earth column to evaporate the toluene layer on a rotary evaporator to obtain 6 g of 2,8-diphenyldibenzo[b,d]thiophene (2,8-diphenyl-). Dibenzo[b,d]thiophene). 6 g of 2,8-diphenyldibenzo[b,d]thiophene was dissolved in 80 ml of anhydrous tetrahydrofuran under a nitrogen atmosphere, and the solution was cooled to -78 °C. 20.0 ml of n-butyl lithium (n-butyl lithium 1.6 M solution) was added dropwise to the reaction mixture, and stirring was continued until the temperature was equilibrated with room temperature. The reaction mixture was again cooled to -60 ° C, and 5.67 mL of trimethyl borate was added and stirring was continued until overnight. The reaction was quenched with 20% aqueous hydrochloric acid and treated with ethyl acetate The organic layer was extracted with an ester, and the extracted ethyl acetate layer was washed with water, dried over anhydrous sodium sulfate and evaporated to dryness to give 4.5 g of 2,8-diphenyldibenzo[b,d]thiophene-4-boronic acid ( 2,8-diphenyldibenzo[b,d]thiophene-4-boronic acid).

3.8 g of 3-bromo-7,12-diphenylbenzo[k]fluoranthene prepared by a conventional method and 3.5 g of 2,8-diphenyldibenzo[b,d]thiophene-4-boronic acid were placed. Mix in 50 ml of toluene. 0.5 g of tetrakis(triphenylphosphine)palladium, 3.8 g of potassium carbonate and 50 ml of an aqueous ethanol solution were added, and the mixture was refluxed with nitrogen. The progress of the reaction was monitored by thin layer chromatography for 6 hours. The reaction was quenched with water, further extracted with water and chromatographed to afford toluene. The organic layers were combined and evaporated to dryness on a rotary evaporator.

The glass transition temperature of Compound A5 was 194 °C. The visible light-ultraviolet absorption peak wavelength of the compound A5 is 397 nm and 419 nm, and the photoluminescence spectrum of the compound A5 has an emission wavelength of 446 nm.

The nuclear magnetic resonance spectrum of Compound A5 is shown in Figure 6.

¹ H NMR (CDCl ₃ , δ): 8.46-8.42 (m, 2H); 7.807.56 (m, 20H); 7.51-7.36 (m, 9H); 7.29-7.24 (m, 1H); 6.74 (d, 1H); 6.63 (d, 1H).

Element Example 1 (Preparation of Organic Electroluminescent Device)

Before the substrate is loaded into the evaporation system, the substrate is degreased by solvent and ultraviolet ozone. Thereafter, the substrate is transferred to a vacuum deposition chamber where all layers forming the elements are deposited. The substrate is placed on a heated vapor deposition boat at a vacuum of about 10-6 Torr, and the layers as shown in Fig. 2 are sequentially deposited: a) hole injection layer, thickness 30 nm, HAT-CN; b) hole transport layer, thickness 110 nm, N, N'-di-1-naphthyl-N, N'-diphenyl-4 , 4'-diaminobiphenyl (N, N'-di-1-naphthyl-N, N'-diphenyl-4, 4'-diaminobiphenyl, NPB); c) luminescent layer, thickness 30 nm, containing BH mixed with 3 vol% BD, (BH and BD are trade names of Taiwan 昱Ra photoelectric Technology Co., Ltd.); d) electron transport layer, thickness 15 nm, containing compound A1; e) electron injection layer, thickness 1 Nano, lithium fluoride (LiF); and f) cathode, about 150 nm thick, containing compound A1.

The structure of the element example 1 can be expressed as follows: ITO/HAT-CN (30 nm) / NPB (110 nm) / BH - 3% BD (30 nm) / compound A1 (15 nm) / LiF ( 1 nm) / Compound A1 (150 nm).

After deposition to form the above layers, the device is transferred from the deposition chamber to a dry box and then encapsulated with a UV-cured epoxy resin and a glass cover containing a moisture absorbent. The organic electroluminescent device has a light-emitting area of 3 square millimeters. After connecting an external power source, the organic electroluminescent element is used in direct current Operating under voltage, the nature of its illumination is shown in Table 2 below.

The luminescent properties of all fabricated organic electroluminescent elements were measured using a constant current (KEITHLEY 2400 Source Meter, made by Keithley Instruments, Inc., Cleveland, Ohio) and a photometer (PHOTO RESEARCH SpectraScan PR 650, made by Photo Research, Inc., Chatsworth, Calif.) was measured at room temperature.

The lifetime (or stability) of the component is tested using a constant current at room temperature and at different initial luminosities depending on the color of the luminescent layer. The color of light is represented by the CIE coordinates set by the International Commission on Illumination.

Element Example 2 (Preparation of Organic Electroluminescent Device)

The manufacturing method of the element example 2 was similar to that of the element example 1, except that the compound A1 of the electron transporting layer in the element example 1 was doped with an n-type doped lithium quinolate in a ratio of 1:1. The structure of the element example 2 can be expressed as: ITO/HAT-CN (30 nm) / NPB (110 nm) / BH - 3% BD (30 nm) / Compound A1 doped with Liq (15 nm) ) / LiF (1 nm) / compound A1 (150 nm).

Comparative Example 1 (Preparation of organic electroluminescent device)

The manufacturing method of Comparative Example 1 was similar to that of the device example 1, except that the compound A1 of the electron transporting layer in the element example 1 was replaced with Alq ₃ . The structure of Comparative Example 1 can be expressed as follows: ITO/HAT-CN (30 nm) / NPB (110 nm) / BH - 3% BD (30 nm) / Alq ₃ (15 nm) / LiF (1 Nano) / Compound A1 (150 nm).

The luminescence spectrum, maximum luminous efficiency, driving voltage, and power efficiency of the organic electroluminescent device fabricated in the device examples are shown in Table 2. The luminescence spectrum of the element example 1-2 is as shown in Fig. 7, and the luminance and voltage contrast diagrams of the organic electroluminescence element are as shown in Fig. 8.

(industrial use)

As described above, the organic electroluminescent device comprising the compound of the present invention can fully realize characteristics of high luminous efficiency, thermal stability, extremely low driving voltage, and long service life. Therefore, the organic electroluminescent device of the present invention is suitable for use as a display for a flat panel display or a mobile communication device, and uses the characteristics of the surface illuminator as a light source and a marker plate, and has extremely high technical value.

Although the present invention has been disclosed and described with respect to the specific embodiments thereof, it will be apparent to those skilled in the art Therefore, the scope of protection of the present invention is attached to the present case. The scope defined in the scope of application for patent application shall prevail.

Claims (8)

A compound of formula I: Wherein X and Y independently represent an aromatic hydrocarbon or a heteroaromatic hydrocarbon having 5 to 10 carbon atoms, wherein the aromatic hydrocarbon is optionally substituted with 1 to 3 methyl groups; and Ar ₁ to Ar ₅ each independently represent hydrogen, An unsubstituted or substituted aromatic hydrocarbon having 4 to 12 carbon atoms or an unsubstituted or substituted condensed polycyclic aromatic hydrocarbon having 4 to 12 carbon atoms, each of Ar ₆ to Ar ₇ independently having 4 to 12 An unsubstituted or substituted aromatic hydrocarbon having one carbon atom, or an unsubstituted or substituted condensed polycyclic aromatic hydrocarbon having 4 to 12 carbon atoms, or Ar ₁ to Ar ₇ optionally forming a ring with the adjacent aromatic hydrocarbon A fused or fused aromatic ring system. The compound of claim 1, wherein the compound is selected from the group consisting of Groups II to XIII: Wherein X and Y independently represent an aromatic hydrocarbon or a heteroaromatic hydrocarbon having 5 to 10 carbon atoms, wherein the aromatic hydrocarbon is optionally substituted with 1 to 3 methyl groups, and R ₁ to R ₇ are independently selected from hydrogen a group consisting of hydrazine, an alkyl group, an alkoxy group, an amino group, a methoxyalkyl group, a cyano group, an aryl group, and a heteroaryl group. The compound according to claim 1 or 2, wherein X and Y are selected from the group consisting of phenyl, 2-tolyl, 3-tolyl, 4-tolyl, 4-pyridyl, 1-naphthyl and A group consisting of 2-naphthyl groups. An organic electroluminescent device is a compound represented by a structure of a group consisting of Formulas II to XIII. The organic electroluminescent device according to claim 4, wherein the compound is used as an electron transport layer or an electron injection layer in a single material or a combination of n-type dopant materials. The organic electroluminescent device of claim 4, wherein the compound is used as a material of one of a light-emitting layer, a hole blocking layer or an electron blocking layer. The organic electroluminescent device according to claim 4, wherein the compound is used as a material in the light-emitting layer and is used in combination with a fluorescent or phosphorescent emitter. The organic electroluminescent device according to claim 4, which is a fluorescent organic electroluminescent device or a phosphorescent organic electroluminescent device.