阅读说明：本技术 一种有机发光材料及有机电致发光器件 (Organic light-emitting material and organic electroluminescent device ) 是由 邢其锋 丰佩川 孙伟 胡灵峰 陈跃 于 2020-05-26 设计创作，主要内容包括：本发明涉及一种有机发光材料,所述的有机发光材料具有如下通式(Ⅰ)所示的结构：<Image he="652" wi="475" file="DDA0002508408170000011.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>所述有机发光材料用作所述有机电致发光器件的空穴传输材料。本发明公开的有机发光材料具有多元化稠杂环芳胺连接的母体结构,原子间的键能高,具有良好的热稳定性,并有利于分子间的固态堆积,空穴的跃迁能力强,用作空穴传输层材料使用能有效降低器件电压,提高材料的寿命。所述有机发光材料为多元化稠杂环的衍生物,在空穴传输层中应用,与相邻层级间具有合适的能级水平,有利于空穴的注入和迁移,能够有效降低启亮电压,同时较高的空穴迁移速率,能够在器件中实现良好的发光效率。(The invention relates to an organic luminescent material, which has a structure shown in the following general formula (I):)

1. An organic light-emitting material, characterized in that the organic light-emitting material has a structure represented by the following general formula (I):

wherein Ar is¹-Ar⁴Selected from C unsubstituted or substituted by Ra₆-C₃₀Aryl of (2), unsubstituted or Ra-substituted C₃-C₃₀The heteroaryl group of (a);

R¹-R²is selected from C₁-C₁₀Alkyl radical, C₁-C₆Cycloalkyl, C unsubstituted or substituted by Ra₆-C₃₀Aryl, C unsubstituted or substituted by Ra₃-C₃₀A heteroaryl group;

R³-R⁶，R⁷-R¹⁰selected from hydrogen, C₁-C₁₀Alkyl radical, C₁-C₆Cycloalkyl, C unsubstituted or substituted by Ra₆-C₃₀Aryl, C unsubstituted or substituted by Ra₃-C₃₀Heteroaryl, and R³-R⁶、R⁷-R¹⁰Adjacent substituents can be connected to form a ring;

L¹，L²selected from C unsubstituted or substituted by Ra₆-C₃₀Aryl, C unsubstituted or substituted by Ra₃-C₃₀A heteroaryl group.

2. The organic light-emitting material according to claim 1, wherein Ar is selected from the group consisting of¹，Ar⁴Any one selected from the following substituted or unsubstituted groups: phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, triphenylene, fluorenyl, pyridyl, benzofuranyl, dibenzofuranyl, aza-dibenzofuranyl, benzothienyl, dibenzothienyl, aza-dibenzothienyl, 9-dimethylfluorenyl, spirofluorenyl, arylamine, carbazolyl.

3. The organic light-emitting material of claim 1, wherein R is¹-R²Selected from methyl, ethyl, cyclopentyl, cyclohexyl, any one of the following unsubstituted or substituted by Ra: phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, triphenylene, fluorenyl, pyridyl, pyridazinyl, pyrimidinyl, pyrazinyl, quinolyl, isoquinolyl, quinazolinyl, quinoxalinyl, cinnolinyl, naphthyridinyl, triazinyl, pyridopyrazinyl, furyl, benzofuryl, dibenzofuryl, aza-dibenzofuryl, thienyl, benzothienyl, dibenzothienyl, aza-dibenzothienyl, 9-dimethylfluorenyl, spirofluorenyl, arylamine, carbazole groups.

4. The method of claim 1An organic light-emitting material, wherein R is³-R⁶And R⁷-R¹⁰Independently of one another, from hydrogen, methyl, ethyl, cyclopentyl, cyclohexyl, any of the following groups which are unsubstituted or substituted by Ra: phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, triphenylene, fluorenyl, pyridyl, pyridazinyl, pyrimidinyl, pyrazinyl, quinolyl, isoquinolyl, quinazolinyl, quinoxalinyl, cinnolinyl, naphthyridinyl, triazinyl, pyridopyrazinyl, furyl, benzofuryl, dibenzofuryl, aza-dibenzofuryl, thienyl, benzothienyl, dibenzothienyl, aza-dibenzothienyl, 9-dimethylfluorenyl, spirofluorenyl, arylamine, carbazole groups.

5. The organic light-emitting material of claim 1, wherein L is¹，L²Any one of the following subgroups of compounds selected from the group consisting of a bond, or unsubstituted or substituted with Ra: benzene, biphenyl, terphenyl, naphthalene, phenanthrene, triphenylene, fluorene, pyridine, pyridazine, pyrimidine, pyrazine, quinoline, isoquinoline, quinazoline, quinoxaline, cinnoline, naphthyridine, triazine, pyridopyrazine, furan, benzofuran, dibenzofuran, aza-dibenzofuran, thienylene, benzothiophene, dibenzothiophene, aza-dibenzothiophene, 9-dimethylfluorene, spirofluorene, arylamine, carbazole.

6. An organic light-emitting material according to claim 1, wherein the organic light-emitting material is selected from the following compounds represented by a1-a 24:

7. an organic electroluminescent device comprising the organic luminescent material according to any one of claims 1 to 6.

8. An organic electroluminescent device according to claim 7, characterized in that the organic luminescent material is used as a hole transport material of the organic electroluminescent device.

Technical Field

The invention relates to an organic luminescent material and an organic electroluminescent device, belonging to the technical field of luminescent materials.

Background

Electroluminescence (EL) refers to a phenomenon in which a light emitting material emits light when excited by a current and an electric field under the action of an electric field, and is a light emitting process in which electric energy is directly converted into light energy. The organic electroluminescent display (hereinafter referred to as OLED) has a series of advantages of self-luminescence, low-voltage dc driving, full curing, wide viewing angle, light weight, simple composition and process, etc., and compared with the liquid crystal display, the organic electroluminescent display does not need a backlight source, and has a large viewing angle, low power, a response speed 1000 times that of the liquid crystal display, and a manufacturing cost lower than that of the liquid crystal display with the same resolution. Therefore, the organic electroluminescent device has very wide application prospect.

With the continuous advance of the OLED technology in the two fields of lighting and display, people pay more attention to the research on efficient organic materials affecting the performance of OLED devices, and an organic electroluminescent device with good efficiency and long service life is generally the result of the optimized matching of device structures and various organic materials, which provides great opportunities and challenges for chemists to design and develop functional materials with various structures.

Organic electroluminescent materials have many advantages over inorganic luminescent materials, such as: the processing performance is good, a film can be formed on any substrate by an evaporation or spin coating method, and flexible display and large-area display can be realized; the optical property, the electrical property, the stability and the like of the material can be adjusted by changing the structure of molecules, and the selection of the material has a large space. In the most common OLED device structures, the following classes of organic materials are typically included: hole injection materials, hole transport materials, electron transport materials, and light emitting materials (dyes or doped guest materials) and corresponding host materials of each color.

Disclosure of Invention

Aiming at the defects in the prior art, the invention provides an organic light-emitting material and an organic light-emitting device, wherein the organic light-emitting material has good thermodynamic stability when being applied to the organic light-emitting device and has long service life in the device.

The technical scheme for solving the technical problems is as follows: an organic light-emitting material having a structure represented by the following general formula (I):

wherein Ar is¹-Ar⁴Selected from C unsubstituted or substituted by Ra₆-C₃₀Aryl of (2), unsubstituted or Ra-substituted C₃-C₃₀The heteroaryl group of (a);

R¹-R²is selected from C₁-C₁₀Alkyl radical, C₁-C₆Cycloalkyl, C unsubstituted or substituted by Ra₆-C₃₀Aryl, C unsubstituted or substituted by Ra₃-C₃₀A heteroaryl group;

R³-R⁶，R⁷-R¹⁰selected from hydrogen, C₁-C₁₀Alkyl radical, C₁-C₆Cycloalkyl, C unsubstituted or substituted by Ra₆-C₃₀Aryl, C unsubstituted or substituted by Ra₃-C₃₀Heteroaryl, and R³-R⁶、R⁷-R¹⁰Adjacent substituents can be connected to form a ring;

L¹，L²selected from C unsubstituted or substituted by Ra₆-C₃₀Aryl, C unsubstituted or substituted by Ra₃-C₃₀A heteroaryl group.

Preferably, Ar is¹,Ar⁴Any one selected from the following substituted or unsubstituted groups: phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, triphenylene, fluorenyl, pyridyl, benzofuranyl, dibenzofuranyl, aza-dibenzofuranyl, benzothienyl, dibenzothienyl, aza-dibenzothienyl, 9-dimethylfluorenyl, spirofluorenyl, arylamine, carbazolyl.

Preferably, said R is¹-R²Selected from methyl, ethyl, cyclopentyl, cyclohexyl, any one of the following unsubstituted or substituted by Ra: phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, triphenylene, fluorenyl, pyridyl, pyridazinyl, pyrimidinyl, pyrazinyl, quinolyl, isoquinolyl, quinazolinyl, quinoxalinyl, cinnolinyl, naphthyridinyl, triazinyl, pyridopyrazinyl, furyl, benzofuryl, dibenzofuryl, aza-dibenzofuryl, thienyl, benzothienyl, dibenzothienyl, aza-dibenzothienyl, 9-dimethylfluorenyl, spirofluorenyl, arylamine, carbazole groups.

Preferably, said R is³-R⁶And R⁷-R¹⁰Independently of one another, from hydrogen, methyl, ethyl, cyclopentyl, cyclohexyl, any of the following groups which are unsubstituted or substituted by Ra: phenyl, biphenyl, terphenyl, naphthyl, phenanthryl, triphenylene, fluorenyl, pyridyl, pyridazinyl, pyrimidinyl, pyrazinyl, quinolyl, isoquinolyl, quinazolinyl, quinoxalinyl, cinnolinyl, naphthyridinyl, triazinyl, pyridopyrazinyl, furyl, benzofuryl, dibenzofuryl, aza-dibenzofuryl, thienyl, benzothienyl, dibenzothienyl, aza-dibenzothienyl, 9-dimethylfluorenyl, spirofluorenyl, arylamine, carbazole groups.

Preferably, said L¹，L²Any one of the following subgroups of compounds selected from the group consisting of a bond, or unsubstituted or substituted with Ra: benzene, biphenyl, terphenyl, naphthalene, phenanthrene, triphenylene, fluorene, pyridine, pyridazine, pyrimidine, pyrazine, quinoline, isoquinoline, quinoline, and naphthalene,Quinazoline, quinoxaline, cinnoline, naphthyridine, triazine, pyridopyrazine, furan, benzofuran, dibenzofuran, aza-dibenzofuran, thienylene, benzothiophene, dibenzothiophene, aza-dibenzothiophene, 9-dimethylfluorene, spirofluorene, arylamine, carbazole.

Preferably, the organic luminescent material is selected from compounds represented by the following A1-A24:

the invention also discloses an organic electroluminescent device which comprises the organic luminescent material.

The organic light-emitting material is used as a hole transport material of the organic electroluminescent device.

The invention has the beneficial effects that:

the organic luminescent material disclosed by the invention has a parent structure connected by diversified fused heterocyclic arylamines, has high bond energy among atoms, good thermal stability, strong hole transition capability and capability of being used as a hole transport layer material, is beneficial to solid accumulation among molecules, and can effectively reduce the voltage of a device and prolong the service life of the material.

The organic luminescent material is a derivative of diversified fused heterocycles, is applied to a hole transport layer, has a proper energy level with an adjacent layer, is beneficial to injection and migration of holes, can effectively reduce the starting voltage, has a high hole migration rate, and can realize good luminous efficiency in a device. The organic luminescent material compound provided by the invention has a larger conjugated plane, is beneficial to molecular accumulation, shows good thermodynamic stability and shows a long service life in a device.

Meanwhile, the preparation process of the organic luminescent material is simple and easy to implement, the raw materials are easy to obtain, and the organic luminescent material is suitable for industrial production.

Detailed Description

The present invention will be described in detail with reference to the following embodiments in order to make the aforementioned objects, features and advantages of the invention more comprehensible. In the following description, numerous specific details are set forth in order to provide a thorough understanding of the present invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

The organic luminescent material of the present application can be used as a hole transport material in an organic electroluminescent device.

In the present application, there is no particular limitation on the kind and structure of the organic electroluminescent device as long as the organic light emitting material provided herein can be used. For convenience, the present application is described with an organic light emitting diode as an example, but this is not meant to limit the scope of the present application in any way. It is understood that all organic electroluminescent devices capable of using the organic luminescent material of the present invention are within the scope of the present invention.

In general, an organic light emitting diode includes first and second electrodes on a substrate, and an organic material layer between the electrodes, which may be a multi-layered structure. For example, the organic material layer may include a hole injection layer, a hole transport layer, a light emitting layer, an electron transport layer, an electron injection layer, and the like.

In the present application, the substrate is not particularly limited, and conventional substrates used in organic electroluminescent devices in the related art, for example, glass, polymer materials, and glass and polymer materials with TFT components and the like may be used.

In the present application, the anode material is not particularly limited, and may be Indium Tin Oxide (ITO), Indium Zinc Oxide (IZO), tin dioxide (SnO) known in the art₂) Transparent conductive materials such as zinc oxide (ZnO), metal materials such as silver and its alloys, aluminum and its alloys, organic conductive materials such as PEDOT (poly-3, 4-ethylenedioxythiophene), and multilayer structures of the above materials.

In the present application, the cathode material is not particularly limited, and may be selected from, for example, but not limited to, a magnesium silver mixture, metal such as LiF/Al, ITO, a metal mixture, an oxide, and the like.

In the present application, the organic electroluminescent diode (OLED) may further include a hole injection layer, a hole transport layer, and the like between the light emitting layer and the anode, and these layers may use, but are not limited to, at least one of HT-1 to HT-31 listed below, and these materials may be used alone or in combination of a plurality of them.

In the present application, the device light emitting layer may comprise a host material and a light emitting dye, wherein the host material includes, but is not limited to, one or more combinations of conventional materials as shown in GPH-1 to GPH-80 below.

In a preferred embodiment of the invention, the light-emitting layer employs phosphorescent electroluminescence technology. The light-emitting layer is doped with a phosphorescent dopant, and the phosphorescent dopant can be selected from but not limited to a combination of one or more of RPD-1 to RPD-28 listed below.

The electron transport materials include, but are not limited to, combinations of one or more of the ET-1 through ET-57 materials listed below. The electron transport materials of the present application may be used in combination with one or more of these materials.

In addition, an electron injection layer between the electron transport layer and the cathode can be further included in the OLED device, and the material of the electron injection layer is not particularly limited, and for example, LiQ, LiF, NaCl, CsF, Li in the prior art can be included but not limited thereto₂O、Cs₂CO₃One or a combination of more of materials such as BaO, Na, Li, Ca and the like.

In the present application, a comparative experiment was performed using HT-27 with the organic light emitting material of the present invention.

The method for synthesizing the compound of the present application is not particularly limited, and the synthesis can be carried out by any method known to those skilled in the art. The following illustrates the synthesis of the compounds of the present application.

Synthetic examples

Synthesis example 1: synthesis of Compound A1

Under the protection of nitrogen, dissolving anthraquinone (100mmol, 1.0eq) in 500ml tetrahydrofuran, adding methyl magnesium bromide (200mmol, 2.0eq) dropwise at 0 ℃, controlling the temperature, naturally heating after the dropwise addition is finished, and reacting for 12 hours. After the reaction, water was added to the reaction solution, and the organic phase was separated, dried and concentrated to obtain intermediate M1.

Under nitrogen protection, M1(100mmol, 1.0eq) and triphenylamine (200mmol, 2.0eq) were dissolved in 500ml of glacial acetic acid, heated to reflux, and reacted for 12 h. After the reaction, water was added to the reaction solution to precipitate a solid, which was then filtered, dried, and recrystallized from toluene to obtain A1.

¹H NMR(400MHz,Chloroform)7.50-7.36(m,4H),7.24(d,J＝8.4Hz,4H),7.21–7.15(m,6H),7.08-7.00(m,4H),2.28(s,3H).

M/Z is theoretical value, 694.92; experimental value, 694.5.

Synthesis example 2: synthesis of Compound A4

Under the protection of nitrogen, dissolving anthraquinone (100mmol, 1.0eq) in 500ml tetrahydrofuran, dropping methyl magnesium bromide (100mmol, 1.0eq) at 0 ℃, controlling the temperature, naturally heating after dropping, and reacting for 12 hours. After the reaction, water was added to the reaction solution, and the organic phase was separated, dried and concentrated to obtain intermediate M1.

Under the protection of nitrogen, dissolving M1(100mmol, 1.0eq) in 500ml of tetrahydrofuran, adding cyclohexyl magnesium bromide (100mmol, 1.0eq) dropwise at 0 ℃, controlling the temperature, naturally heating after dropwise addition, and reacting for 12 hours. After the reaction, water was added to the reaction solution, and the organic phase was separated, dried and concentrated to obtain intermediate M2.

Under nitrogen protection, M2(100mmol, 1.0eq) and triphenylamine (200mmol, 2.0eq) were dissolved in 500ml of glacial acetic acid, heated to reflux, and reacted for 12 h. After the reaction, water was added to the reaction solution to precipitate a solid, which was then filtered, dried, and recrystallized from toluene to obtain A4.

¹H NMR(400MHz,Chloroform)7.75-7.62(m,6H),7.49(d,J＝8.4Hz,4H),7.35(d,J＝8.0Hz,6H),7.17(dd,J＝12.4,8.4Hz,12H),7.06-6.98(m,8H),1.80(s,3H),1.69(d,J＝10.0Hz,6H),1.31-1.03(m,5H).

M/Z is theoretical value, 763.04; experimental value, 762.8.

Synthetic example 3: synthesis of Compound A10

Under the protection of nitrogen, dissolving anthraquinone (100mmol, 1.0eq) in 500ml tetrahydrofuran, adding methyl magnesium bromide (200mmol, 2.0eq) dropwise at 0 ℃, controlling the temperature, naturally heating after the dropwise addition is finished, and reacting for 12 hours. After the reaction, water was added to the reaction solution, and the organic phase was separated, dried and concentrated to obtain intermediate M1.

Under the protection of nitrogen, M1(100mmol, 1.0eq) and 4-biphenyl-diphenylamine (100mmol, 1.0eq) are dissolved in 500ml of glacial acetic acid, and the mixture is heated to reflux and reacted for 12 hours. After the reaction, water was added to the reaction solution to precipitate a solid, which was then filtered, dried, and recrystallized from toluene to obtain M2.

Under the protection of nitrogen, M2(100mmol, 1.0eq) and 2- (9, 9-dimethylfluorene) -diphenylamine (100mmol, 1.0eq) were dissolved in 500ml of glacial acetic acid, heated to reflux and reacted for 12 h. After the reaction, water was added to the reaction solution to precipitate a solid, which was then filtered, dried, and recrystallized from toluene to obtain A10.

¹H NMR(400MHz,Chloroform)8.12–8.04(m,3H),7.85(s,1H),7.74(d,J＝8.8Hz,3H),7.62-7.50(d,J＝8.0Hz,6H)7.44(dd,J＝8.6,6.8Hz,4H),7.37(dd,J＝8.0,6.4Hz,6H),7.32–7.22(m,9H),7.19–7.06(m,14H),6.98(d,J＝12.4Hz,6H),2.28(s,6H),1.69(s,6H).

M/Z is theoretical value, 887.18; experimental value, 886.9.

Synthetic example 4: synthesis of Compound A17

Under the protection of nitrogen, dissolving naphthonaphthonaphthoquinone (100mmol, 1.0eq) in 500ml tetrahydrofuran, adding methyl magnesium bromide (200mmol, 2.0eq) dropwise at 0 ℃, controlling the temperature, naturally heating after dropwise addition, and reacting for 12 h. After the reaction, water was added to the reaction solution, and the organic phase was separated, dried and concentrated to obtain intermediate M1.

Under the protection of nitrogen, M1(100mmol, 1.0eq) and 4-biphenyl-diphenylamine (100mmol, 1.0eq) are dissolved in 500ml of glacial acetic acid, and the mixture is heated to reflux and reacted for 12 hours. After the reaction, water was added to the reaction solution to precipitate a solid, which was then filtered, dried, and recrystallized from toluene to obtain A17.

¹H NMR(400MHz,Chloroform)7.85-7.78(m,4H),7.63–7.50(m,8H),7.44–7.30(m,9H),7.26–7.14(m,12H),7.12(d,J＝10.0Hz,4H),7.06(d,J＝8.6Hz,6H),7.00(s,1H),6.52(s,1H),2.34(s,6H).

M/Z is theoretical value, 897.18; experimental value, 896.7.

Synthesis example 5: synthesis of Compound A21

Under the protection of nitrogen, dissolving anthraquinone (100mmol, 1.0eq) in 500ml tetrahydrofuran, dropping cyclohexyl magnesium bromide (200mmol, 2.0eq) at 0 ℃, controlling the temperature, naturally heating after dropping, and reacting for 12 hours. After the reaction, water was added to the reaction solution, and the organic phase was separated, dried and concentrated to obtain intermediate M1.

Under the protection of nitrogen, dissolving M1(100mmol, 1.0eq) in 500ml of tetrahydrofuran, adding phenyl magnesium bromide (200mmol, 2.0eq) dropwise at 0 ℃, controlling the temperature, naturally heating after dropwise addition, and reacting for 12 hours. After the reaction, water was added to the reaction solution, and the organic phase was separated, dried and concentrated to obtain intermediate M2.

Under the protection of nitrogen, M2(100mmol, 1.0eq) and 2-dibenzothiophene-diphenylamine (100mmol, 1.0eq) are dissolved in 500ml of glacial acetic acid, and the mixture is heated to reflux and reacted for 12 hours. After the reaction, water was added to the reaction solution to precipitate a solid, which was then filtered, dried, and recrystallized from toluene to obtain M3.

Under nitrogen protection, M3(100mmol, 1.0eq) and triphenylamine (100mmol, 1.0eq) were dissolved in 500ml of glacial acetic acid, and the mixture was heated to reflux and reacted for 12 hours. After the reaction, water was added to the reaction solution to precipitate a solid, which was then filtered, dried, and recrystallized from toluene to obtain A21.

¹H NMR(400MHz,Chloroform)7.94-7.85(m,5H),7.64–7.51(m,11H),7.30(s,1H),7.19(dt,J＝13.6,9.6Hz,8H),7.08(d,J＝10.0Hz,8H),7.00(dd,J＝10.8,7.6Hz,6H),6.93-6.75(m,4H),1.92(s,1H),1.69(d,J＝10.0Hz,2H),1.31-1.03(m,8H).

M/Z is theoretical value, 931.25; experimental value, 931.1.

Other compounds of the present application can be synthesized by selecting suitable starting materials according to the methods described in examples 1 to 5 above, or by selecting any other suitable methods and starting materials.

The application also provides an organic electroluminescent device which comprises the organic luminescent material provided by the application.

In the present application, the method of manufacturing the OLED device is not particularly limited, and may be manufactured using any method known in the art.

Application example 1

Carrying out ultrasonic treatment on the glass plate coated with the ITO transparent conductive layer in a commercial cleaning agent, washing in deionized water, carrying out ultrasonic oil removal in an acetone-ethanol mixed solvent, baking in a clean environment until the water is completely removed, cleaning by using ultraviolet light and ozone, and bombarding the surface by using low-energy solar beams;

placing the glass substrate with the anode in a vacuum chamber, and vacuumizing to less than 10 DEG^-5In the torr, HT-11 is evaporated in vacuum on the anode layer film to be used as a hole injection layer, the evaporation rate is 0.1nm/s, and the evaporation film thickness is 10 nm;

vacuum evaporating an A1 material on the hole injection layer to form a hole transport layer, wherein the evaporation rate is 0.1nm/s, and the total film thickness is 80 nm;

a light-emitting layer of the device is vacuum evaporated on the hole transport layer, the light-emitting layer comprises a main material GHP-16 and a dye material RPD-1, evaporation is carried out by using a multi-source co-evaporation method, the evaporation rate of the main material GHP-16 is adjusted to be 0.1nm/s, the evaporation rate of the dye RPD-1 is 3% of the evaporation rate of the main material, and the total thickness of the evaporation film is 30 nm;

vacuum evaporating an electron transport layer on the light emitting layer, wherein an ET42 material is selected as an electron transport material, the evaporation rate is 0.1nm/s, and the total film thickness of evaporation is 30 nm;

LiF with the thickness of 0.5nm is vacuum-evaporated on the Electron Transport Layer (ETL) to be used as an electron injection layer, and an Al layer with the thickness of 150nm is used as a cathode of the device.

The organic electroluminescent device prepared by the above process was subjected to the following performance measurement:

the organic electroluminescent devices obtained in examples and comparative examples were measured for driving voltage and current efficiency and lifetime at the same luminance using a digital source meter and a luminance meter, and specifically, the luminance of the organic electroluminescent devices reached 5000cd/m when the voltage was increased at a rate of 0.1V/sec²The current density is measured at the same time as the driving voltage; the ratio of the brightness to the current density is the current efficiency; the life test of LT95 is as follows: using a luminance meter at 5000cd/m²The luminance drop of the organic electroluminescent device was measured to be 4750cd/m by maintaining a constant current at luminance²Time in hours.

Application examples 2 to 6

The organic light emitting materials a5, a12, and a23 of the present invention were used as hole transporting materials, respectively, and the rest was the same as in example 1. The test results are shown in Table 1.

Comparative examples of application

The same as in application example 1 was repeated except that HT27 was used as a hole transport material, and the results of the tests are shown in Table 1.

Table 1 organic electroluminescent device performance results

As can be seen from the data in the table 1, the novel organic material prepared by the invention is used for the hole transport material of the organic electroluminescent device, can effectively reduce the rise-fall voltage, improve the current efficiency and prolong the service life of the device, and is a hole transport material with good performance.

The technical features of the embodiments described above may be arbitrarily combined, and for the sake of brevity, all possible combinations of the technical features in the embodiments described above are not described, but should be considered as being within the scope of the present specification as long as there is no contradiction between the combinations of the technical features.

The above-mentioned embodiments only express several embodiments of the present invention, and the description thereof is more specific and detailed, but not construed as limiting the scope of the invention. It should be noted that, for a person skilled in the art, several variations and modifications can be made without departing from the inventive concept, which falls within the scope of the present invention. Therefore, the protection scope of the present patent shall be subject to the appended claims.