Diarylamine organic compound and organic electroluminescent device prepared from same

Abstract

The invention discloses a bis-arylamine organic compound and an organic electroluminescent device prepared from the bis-arylamine organic compound, and belongs to the technical field of semiconductor materials. The structure of the compound is as shown in a general formula (1): # imgabs0 #. The organic compound has excellent hole transport capability and thermal stability, and when a hole transport material of an organic electroluminescent device is formed by using the bis-arylamine organic compound disclosed by the invention, the effects of improving the efficiency of the device and prolonging the service life of the device can be displayed at the same time; particularly, the high-temperature service life of the device is prolonged.

Description

[0001] This invention application is based on the prior application number: 202111461952.X, the application date is: December 02, 2021, and the invention name is: A diaromatic amine organic compound and an organic electroluminescent device prepared therefrom. Technical Field

[0002] The present invention relates to the technical field of semiconductor materials, in particular to a diarylamine organic compound and an organic electroluminescent device prepared therefrom. Background Art

[0003] The carriers (holes and electrons) in an organic electroluminescent device (OLED) are injected into the device by the two electrodes of the device under the drive of an electric field, and meet in the organic light-emitting layer to recombine and emit light. High-performance organic electroluminescent devices require various organic functional materials to have good photoelectric properties. For example, as a charge transport material, it is required to have good carrier mobility. The injection and transport properties of the hole injection layer materials and hole transport layer materials used in existing organic electroluminescent devices are relatively weak, and the hole injection and transport rates do not match the electron injection and transport rates, resulting in a large offset in the recombination area, which is not conducive to the stability of the device. In addition, the reasonable energy level matching of the hole injection layer material and the hole transport layer material is an important factor in improving the efficiency and life of the device. Therefore, how to adjust the balance between holes and electrons and adjust the recombination area has always been an important topic in this field.

[0004] Blue organic electroluminescent devices have always been the weak point in the development of full-color OLEDs. Up to now, the efficiency and lifespan of blue light devices have been difficult to be comprehensively improved. Therefore, how to improve the performance of such devices remains a crucial issue and challenge facing this field. Most of the blue light host materials currently used on the market are electron-biased hosts. Therefore, in order to adjust the carrier balance of the light-emitting layer, hole transport materials with excellent hole transport properties are required. The better the hole injection and transport, the more the recombination area will be adjusted to shift away from the electron blocking layer, thereby emitting light away from the interface, improving device performance and increasing lifespan. Therefore, the hole transport area material is required to have high hole injectivity, high hole mobility, high electron blocking properties and high electron weather resistance.

[0005] It is well known in the art that in a high-temperature environment, the difference between electron mobility and hole mobility is more obvious, resulting in blue light devices being electron-rich and hole-deficient in high-temperature environments, and the device life is poor. In order to improve the high-temperature life of blue light devices, it is necessary to improve the mobility of hole transport materials, especially the mobility under high-temperature conditions. Summary of the Invention

[0006] To address the aforementioned issues in the prior art, the present inventors have provided a bisarylamine organic compound and an organic electroluminescent device prepared therefrom. The organic compound exhibits excellent hole-transporting ability and thermal stability. When used as a hole-transport material in an organic electroluminescent device, the bisarylamine organic compound exhibits both improved device efficiency and extended device life, particularly at high temperatures.

[0007] The technical solution of the present invention is as follows: a diarylamine organic compound, the structure of which is shown in general formula (1):

[0008]

[0009] In the general formula (1), a and c are independently represented by the numbers 0 or 1, and a+c=1 or 2;

[0010] R1 to R4 are independently represented by a hydrogen atom, a deuterium atom, a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or substituted furyl group, a substituted or unsubstituted thienyl group, a substituted or unsubstituted benzothienyl group, a substituted or unsubstituted dibenzothienyl group, a substituted or unsubstituted benzofuranyl group, or a substituted or unsubstituted dibenzofuranyl group, and R1 to R4 are connected to the general formula (1) in two ways: substitution and cyclization.

[0011] Ar1 to Ar8 are independently represented by a hydrogen atom, a deuterium atom, a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group or a substituted or unsubstituted biphenyl group, and at least one of Ar1 to Ar8 is not represented by a hydrogen atom or a deuterium atom;

[0012] The substituents for the above substitutable groups are selected from deuterium atoms, methyl groups, ethyl groups, tert-butyl groups, phenyl groups, biphenyl groups or naphthyl groups;

[0013] The m, n, p, and q are independently represented by the numbers 0, 1, 2, 3, 4, or 5;

[0014] Said Ar is represented by the general formula (2);

[0015]

[0016] In the general formula (2), It means that it can form a bond or not;

[0017] Said A is represented by the structure shown in general formula (3), general formula (4) or general formula (5);

[0018]

[0019] Said X represents an oxygen atom or a sulfur atom;

[0020] The R0, R a and R b Each independently represents a hydrogen atom, a deuterium atom, a methyl group, an ethyl group, an isopropyl group, a tert-butyl group, a phenyl group, a naphthyl group or a biphenyl group;

[0021] Wherein, "*" indicates that the general formulas (2) to (5) can be combined with the general formula (1). When general formula (3) to general formula (5) are respectively cyclic with general formula (2), the two carbon atoms at the cyclic position cannot be cyclic with Groups connected.

[0022] The present invention also provides an organic electroluminescent device, which comprises an anode, a hole transport region, a light emitting region, an electron transport region and a cathode in sequence, wherein the hole transport region contains the diarylamine organic compound.

[0023] The beneficial technical effects of the present invention are:

[0024] The compounds of the present invention have the following structural features: aryl-substituted phenyl and fluorenyl serve as bridging groups between the biarylamine structures, wherein one arylamine is connected to one side of the fluorenyl group through the aryl-substituted phenyl group, and the other arylamine is directly connected to the other side of the fluorenyl group through a single bond. The unique connection mode of the bridging group gives the compounds of the present invention the following advantages:

[0025] (1) Device verification proves that this connection method enables the compound of the present invention to have excellent hole mobility. The improvement of hole mobility allows more holes to be injected into the main body, and the increase of exciton concentration in the main body increases the TTA efficiency and exciton utilization, thereby improving the device efficiency.

[0026] (2) This connection method enables the compound of the present invention to have a suitable energy level. The reasonable energy level matching makes the injection and conduction of carriers smoother, prevents accumulation at the interface, and is conducive to improving the interface stability. Excellent interface stability is conducive to improving the life of the device.

[0027] (3) This connection method is conducive to increasing the glass transition temperature of the molecule and at the same time lowering the evaporation temperature of the molecule. That is to say, even if the molecular weight of the molecule is relatively high, it can ensure a lower evaporation temperature. This excellent performance is not only conducive to the thermal evaporation of the material, but also controls the thermal decomposition rate of the material, thereby improving the stability of the material in device applications.

[0028] Furthermore, for the biphenylyl, benzofuranyl, benzothiophenyl, or naphthyl groups characterized by the molecular structure of the present invention, optimizing the groups attached to the biphenylyl group can further enhance the material's performance. For example, selecting groups or group derivatives with strong planarity or large structural radii (including similar groups with parallel ring structures or substitution structures) such as biphenylyl, benzofuranyl, benzothiophenyl, or naphthyl can further enhance the material's stability and mobility, while also facilitating precise control of the material's HOMO energy level, thereby achieving excellent device performance.

[0029] The organic functional materials that constitute OLED devices include not only hole injection conductive materials but also electron injection conductive materials and light-emitting layer materials. Good device application effects require a good carrier balance as a guarantee. Therefore, in order to obtain the best device application effects, the biphenylamine materials that match the characteristic structure of the present invention also require specific electronic materials to be matched. Based on the in-depth research of the inventors, the electronic materials are preferably materials containing nitrogen-containing benzene structural characteristics, such as triazine materials, pyridine materials, pyrazine materials, etc. or derivatives containing these characteristic groups. The biphenylamine organic compounds of the present invention are combined with nitrogen-containing benzene ring electron transport materials to make it easy for electrons and holes to obtain an optimal balance state, and have high efficiency while also having excellent lifespan, and are particularly easy to obtain good device high-temperature life effects. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] Figure 1 is a cross-sectional view of the organic electroluminescent device of the present invention.

[0031] In the figure, 1 represents the substrate layer; 2 represents the anode layer; 3 represents the hole injection layer; 4 represents the hole transport layer; 5 represents the electron blocking layer; 6 represents the light-emitting layer; 7 represents the hole blocking layer; 8 represents the electron transport layer; 9 represents the electron injection layer; 10 represents the cathode layer; and 11 represents the covering layer. DETAILED DESCRIPTION

[0032] The following will be combined with the accompanying drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only part of the embodiments of the present invention, rather than all the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is in no way intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0033] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0034] In the present invention, unless otherwise specified, HOMO means the highest occupied molecular orbital of a molecule, and LUMO means the lowest unoccupied molecular orbital of a molecule. In addition, in the present invention, HOMO and LUMO energy levels are expressed in absolute values, and comparison between energy levels also refers to comparison of their absolute values. Those skilled in the art will appreciate that the larger the absolute value of an energy level, the lower the energy of that energy level.

[0035] In the present disclosure, when a layer or element is referred to as being "on" another layer or substrate, the layer or element may be directly on the other layer or substrate, or intervening layers may also be present. Furthermore, it will be understood that when a layer is referred to as being "between" two layers, the layer may be the only layer between the two layers, or one or more intervening layers may also be present. Like reference numerals refer to like elements throughout.

[0036] In the present invention, when describing electrodes, organic electroluminescent devices, and other structures, terms such as "upper," "lower," "top," and "bottom" that indicate orientation refer only to a particular state and do not imply that the structure can exist only in the described orientation. Conversely, if the structure can be repositioned, such as inverted, the orientation of the structure will change accordingly. Specifically, in the present invention, the "bottom" or "lower" side of an electrode refers to the side of the electrode closest to the substrate during fabrication, while the opposite side, farther from the substrate, is the "top" or "upper" side.

[0037] In this specification, the term "substituted" means that one or more hydrogen atoms on a designated atom or group are replaced by a designated group, provided that the normal valency of the designated atom is not exceeded under the existing circumstances.

[0038] Compound represented by general formula (1):

[0039]

[0040] In the general formula (1), a and c are independently represented by the numbers 0 or 1, and a+c=1 or 2;

[0041] R1 to R4 are independently represented by a hydrogen atom, a deuterium atom, a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or substituted furyl group, a substituted or unsubstituted thienyl group, a substituted or unsubstituted benzothienyl group, a substituted or unsubstituted dibenzothienyl group, a substituted or unsubstituted benzofuranyl group, or a substituted or unsubstituted dibenzofuranyl group, and R1 to R4 are connected to the general formula (1) in two ways: substitution and cyclization.

[0042] Ar1 to Ar8 are independently represented by a hydrogen atom, a deuterium atom, a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group or a substituted or unsubstituted biphenyl group, and at least one of Ar1 to Ar8 is not represented by a hydrogen atom or a deuterium atom;

[0043] The substituents for the above substitutable groups are selected from deuterium atoms, methyl groups, ethyl groups, tert-butyl groups, phenyl groups, biphenyl groups or naphthyl groups;

[0044] The m, n, p, and q are independently represented by the numbers 0, 1, 2, 3, 4, or 5;

[0045] Said Ar is represented by the general formula (2);

[0046]

[0047] In the general formula (2), It means that it can form a bond or not;

[0048] Said A is represented by the structure shown in general formula (3), general formula (4) or general formula (5);

[0049]

[0050] Said X represents an oxygen atom or a sulfur atom;

[0051] The R0, R a and R b Each independently represents a hydrogen atom, a deuterium atom, a methyl group, an ethyl group, an isopropyl group, a tert-butyl group, a phenyl group, a naphthyl group or a biphenyl group;

[0052] Wherein, "*" indicates that the general formulas (2) to (5) can be combined with the general formula (1). When general formula (3) to general formula (5) are respectively cyclic with general formula (2), the two carbon atoms at the cyclic position cannot be cyclic with Groups connected.

[0053] In a preferred embodiment, the structure of the compound is shown in the general formula (2-1):

[0054]

[0055] In the general formula (2-1), the meanings of R1-R4, Ar, Ar1-Ar4, m, n, p, and q are the same as those defined in the general formula (1) above, and at least one of Ar1 to Ar4 is not a hydrogen atom or a deuterium atom.

[0056] In a preferred embodiment, the structure of the compound is as shown in general formula (2-2) to general formula (2-3):

[0057]

[0058] In general formula (2-2) and general formula (2-3), Ar1 and Ar2 are independently substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, or substituted or unsubstituted biphenyl, and the meanings of R1-R4, Ar, m, n, p, and q are the same as those defined in general formula (1) above. In a preferred embodiment, the compounds are as shown in general formulas (3-1) to (3-12);

[0059]

[0060]

[0061] In general formulas (3-1) to (3-12), the meanings of R1-R4, Ar, m, n, p, and q are the same as those defined in general formula (1) above. In a preferred embodiment, the compounds are as shown in general formulas (4-1) to (4-4);

[0062]

[0063] In the general formula (4-1) to the general formula (4-4), Ar1 and Ar2 are independently represented by substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl or substituted or unsubstituted biphenyl, and R1-R4, R a , A, m, n, p, and q have the same meanings as defined in the general formula (1) above.

[0064] In a preferred embodiment, the compound is as shown in general formula (5-1) to general formula (5-7);

[0065]

[0066]

[0067] In the general formula (5-1) and the general formula (5-7), Ar1 and Ar2 are independently represented by substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl or substituted or unsubstituted biphenyl, and R1-R4, R a 、R b , m, n, p, and q have the same meanings as defined in the general formula (1) above.

[0068] In a preferred embodiment, R1-R4 are independently represented by substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, or substituted or unsubstituted biphenyl, and R1-R4 are connected in two ways: substitution and cyclization.

[0069] In a preferred embodiment, m, n, p, and q are represented by the numbers 0 or 1.

[0070] In a preferred embodiment, the specific structure of the compound is any one of the following structures:

[0071]

[0072]

[0073]

[0074]

[0075]

[0076]

[0077]

[0078] organic electroluminescent devices

[0079] The present invention provides an organic electroluminescent device using a diarylamine compound of general formula (1).

[0080] In an exemplary embodiment of the present invention, the organic electroluminescent device comprises an anode, a hole transport region, a light emitting region, an electron transport region and a cathode in sequence, wherein the hole transport region comprises the diarylamine organic compound of formula (1).

[0081] In a preferred embodiment, the hole transport region includes a hole injection layer, a first hole transport layer and a second hole transport layer, and the first hole transport layer and the hole injection layer contain the bisarylamine organic compound;

[0082] Preferably, the hole transport layer comprises the diarylamine organic compound, and the hole injection layer is composed of the diarylamine organic compound and a P-type doping material for the hole injection layer.

[0083] Preferably, the first hole transport layer comprises the bisarylamine organic compound, and the hole injection layer is composed of the bisarylamine organic compound and a P-type doping material for the hole injection layer.

[0084] The organic electroluminescent device of the present invention may be a bottom-emitting organic electroluminescent device, a top-emitting organic electroluminescent device, or a stacked organic electroluminescent device, without particular limitation.

[0085] Any substrate commonly used in organic electroluminescent devices can be used in the organic electroluminescent device of the present invention. Examples include transparent substrates such as glass or transparent plastic substrates; opaque substrates such as silicon substrates; and flexible polyimide (PI) film substrates. Different substrates have varying mechanical strength, thermal stability, transparency, surface smoothness, and water resistance. Depending on the properties of the substrate, its use varies. In the present invention, a transparent substrate is preferably used. The thickness of the substrate is not particularly limited.

[0086] anode

[0087] Preferably, an anode can be formed on a substrate. In the present invention, the anode and the cathode are opposite to each other. The anode can be made of a conductor with a higher work function to facilitate hole injection, and can be, for example, a metal such as nickel, platinum, copper, zinc, silver, or an alloy thereof; a metal oxide such as zinc oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO); a combination of a metal and a metal oxide such as ZnO and Al or ITO and Ag; a conductive polymer such as poly(3-methylthiophene), poly(3,4-(ethylene-1,2-dioxy)thiophene) and polyaniline, but is not limited thereto. The thickness of the anode depends on the material used, and is typically 50-500 nm, preferably 70-300 nm, and more preferably 100-200 nm. In the present invention, a combination of a metal and a metal oxide, ITO and Ag, is preferably used.

[0088] cathode

[0089] The cathode can be made of a conductor with a low work function to facilitate electron injection. Examples include metals or alloys thereof, such as magnesium, calcium, sodium, potassium, titanium, indium, aluminum, silver, tin, and combinations thereof; and multilayer structures such as, but not limited to, LiF / Al, Li2O / Al, and BaF2 / Ca. The thickness of the cathode depends on the material used, but is typically 10-50 nm, preferably 15-20 nm.

[0090] Luminous area

[0091] In the present invention, the light-emitting region may be arranged between the anode and the cathode, and may comprise at least one host material and at least one guest material. As the host material and guest material of the light-emitting region of the organic electroluminescent device of the present invention, light-emitting layer materials for organic electroluminescent devices known in the prior art may be used. The host material may be, for example, a thiazole derivative, a benzimidazole derivative, a polydialkylfluorene derivative or 4,4'-bis(9-carbazolyl)biphenyl (CBP). The host material may use a compound comprising an anthracene group. The guest material may be, for example, quinacridone, coumarin, rubrene, perylene and its derivatives, benzopyran derivatives, rhodamine derivatives or aminostyrene derivatives.

[0092] In a preferred embodiment of the present invention, the light emitting region comprises one or two host material compounds.

[0093] In a preferred embodiment of the present invention, the light-emitting region comprises two host material compounds, and the two host material compounds can form an exciplex.

[0094] In a preferred embodiment of the present invention, the host material of the light-emitting region is selected from one or more of the following compounds BH-1 to BH-11:

[0095]

[0096] In the present invention, the light-emitting region may contain a phosphorescent or fluorescent guest material to improve the fluorescent or phosphorescent properties of the organic electroluminescent device. Specific examples of phosphorescent guest materials include metal complexes of iridium, platinum, etc. For fluorescent guest materials, those commonly used in the art can be used. In a preferred embodiment of the present invention, the guest material of the light-emitting film layer used is selected from one of the following compounds BD-1 to BD-10:

[0097]

[0098]

[0099] In the light-emitting region of the present invention, the ratio of the host material to the guest material used is 99:1 to 70:30, preferably 99:1 to 85:15 and more preferably 97:3 to 87:13, based on mass.

[0100] The thickness of the light emitting region may be 10-50 nm, preferably 15-30 nm, but the thickness is not limited to this range.

[0101] hole transport region

[0102] In the organic electroluminescent device of the present invention, the hole transport region is disposed between the anode and the light emitting region, and includes a hole injection layer, a hole transport layer and an electron blocking layer.

[0103] hole injection layer

[0104] The hole injection material used in the hole injection layer (also called the anode interface buffer layer) is a material that can fully accept holes from the anode at a low voltage, and the highest occupied molecular orbital (HOMO) of the hole injection material is preferably a value between the work function of the anode material and the HOMO of the adjacent organic material layer. In a preferred embodiment of the present invention, the hole injection layer is a mixed film layer of a main organic material and a P-type dopant material. In order to smoothly inject holes from the anode into the organic film layer, the HOMO energy level of the main organic material must have certain characteristics with the P-type dopant material, so that it is possible to realize the charge transfer state between the main material and the dopant material, realize the ohmic contact between the hole injection layer and the anode, and thus realize the efficient injection of holes from the electrode to the hole injection layer. This feature is summarized as: the difference between the HOMO energy level of the main material and the LUMO energy level of the P-type dopant material is ≤0.4eV. Therefore, for hole-type main materials with different HOMO energy levels, different P-type dopant materials need to be selected to match them in order to achieve ohmic contact at the interface and improve the hole injection effect.

[0105] Specific examples of the host organic material preferably include, but are not limited to, metalloporphyrins, oligothiophenes, diarylamine organic materials, hexanitrile hexaazatriphenylene, quinacridone organic materials, perylene organic materials, anthraquinone, polyaniline, and polythiophene conductive polymers. Preferably, the host organic material is a diarylamine organic material.

[0106] Preferably, the P-type doping material is a compound having charge conductivity selected from the following: quinone derivatives or metal oxides, such as tungsten oxide and molybdenum oxide, but not limited thereto.

[0107] In a preferred embodiment of the present invention, the P-type dopant material used is selected from any one of the following compounds P-1 to P-8:

[0108]

[0109] In one embodiment of the present invention, the ratio of the host organic material to the P-type dopant material is 99:1-95:5, preferably 99:1-97:3, based on mass.

[0110] In a preferred embodiment of the present invention, the hole injection layer is a mixed film layer of a diarylamine compound and a P-type dopant material, and the diarylamine compound is a diarylamine compound of the general formula (1).

[0111] The thickness of the hole injection layer of the present invention may be 5-20 nm, preferably 8-15 nm, but the thickness is not limited to this range.

[0112] hole transport layer

[0113] In the organic electroluminescent device of the present invention, a hole transport layer may be provided above the hole injection layer. The hole transport material is a suitable material having a high hole mobility, which can accept holes from the anode or the hole injection layer and transport the holes to the light-emitting layer. Specific examples thereof include, but are not limited to, diarylamine organic materials, conductive polymers, block copolymers having both conjugated and non-conjugated portions, and the like. In a preferred embodiment, the hole transport layer comprises a diarylamine organic compound represented by the same general formula (1) as the hole injection layer.

[0114] The thickness of the hole transport layer of the present invention may be 80, 100 or 200 nm, preferably 100-150 nm, but the thickness is not limited to this range.

[0115] electron blocking layer

[0116] In the organic electroluminescent device of the present invention, an electron-blocking layer may be disposed between the hole-transporting layer and the light-emitting layer, and in particular, may be in contact with the light-emitting layer. Positioning the electron-blocking layer in contact with the light-emitting layer allows precise control of hole transfer at the interface between the light-emitting layer and the hole-transporting layer. In one embodiment of the present invention, the electron-blocking layer material is selected from carbazole-based bisarylamine derivatives. The thickness of the electron-blocking layer may be 5-20 nm, preferably 8-15 nm, but is not limited to this range.

[0117] Electron transport region

[0118] In the organic electroluminescent device of the present invention, the electron transport region is disposed between the light emitting region and the cathode, and includes a hole blocking layer, an electron transport layer and an electron injection layer, but is not limited thereto.

[0119] electron injection layer

[0120] The electron injection layer can be arranged between the electron transport layer and the cathode. The electron injection layer material is generally preferably a material with a low work function, so that electrons are easily injected into the organic functional material layer. Preferably, the electron injection layer material is an N-type metal material. As the electron injection layer material of the organic electroluminescent device of the present invention, the electron injection layer materials for organic electroluminescent devices known in the prior art can be used, for example, lithium; lithium salts, such as 8-hydroxyquinoline lithium, lithium fluoride, lithium carbonate or lithium azide; or cesium salts, cesium fluoride, cesium carbonate or cesium azide. The thickness of the electron injection layer of the present invention can be 0.1-5nm, preferably 0.5-3nm and more preferably 0.8-1.5nm, but the thickness is not limited to this range.

[0121] electron transport layer

[0122] The electron transport layer can be disposed on the light-emitting film layer or (if present) the hole blocking layer. The electron transport layer material is a material that easily accepts electrons from the cathode and transfers the received electrons to the light-emitting layer. Preferably, the material has a high electron mobility. As the electron transport layer of the organic electroluminescent device of the present invention, electron transport layer materials for organic electroluminescent devices known in the prior art can be used, for example, metal complexes of hydroxyquinoline derivatives represented by Alq3, BAlq and LiQ, various rare earth metal complexes, triazole derivatives, triazine derivatives such as 2,4-bis(9,9-dimethyl-9H-fluoren-2-yl)-6-(naphthalene-2-yl)-1,3,5-triazine (CAS No.: 1459162-51-6), imidazole derivatives such as 2-(4-(9,10-di(naphthalene-2-yl)anthracene-2-yl)phenyl)-1-phenyl-1H-benzo[d]imidazole (CAS No.: 561064-11-7, commonly known as LG201), oxadiazole derivatives, etc.

[0123] In a preferred organic electroluminescent device of the present invention, the electron transport region comprises a nitrogen heterocyclic compound represented by the general formula (10-1):

[0124]

[0125] In the general formula (10-1), Ar5, Ar6, and Ar7 are independently selected from substituted or unsubstituted C6-C 30 Aryl, substituted or unsubstituted C2-C 30 One of the heterocyclic groups;

[0126] L3 represents a single bond, a substituted or unsubstituted C6-C 30 Arylene, substituted or unsubstituted C2-C 30 A type of heterocyclylene group;

[0127] X1, X2, and X3 independently represent N or CH, and at least one of X1, X2, and X3 represents N;

[0128] The heteroatoms are each independently selected from N, O or S;

[0129] The substituent for the substituted group is one or more of a deuterium atom, a phenyl group, a naphthyl group, a biphenyl group, a dibenzofuranyl group, a dibenzothienyl group, a pyridyl group or a pyrimidyl group.

[0130] Preferably, the substituted or unsubstituted C6-C 30 The aryl group refers to a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or unsubstituted anthracenyl group, a substituted or unsubstituted phenanthrenyl group, a substituted or unsubstituted tetraphenyl group, a substituted or unsubstituted pyrenyl group, a substituted or unsubstituted biphenyl group, a substituted or unsubstituted p-terphenyl group, a substituted or unsubstituted m-terphenyl group, a substituted or unsubstituted triphenylene group, a substituted or unsubstituted perylenyl group, or a substituted or unsubstituted indenyl group.

[0131] The substituted or unsubstituted C2-C 30 Heteroaryl refers to substituted or unsubstituted furyl, substituted or unsubstituted thienyl, substituted or unsubstituted pyrrolyl, substituted or unsubstituted pyrazolyl, substituted or unsubstituted imidazolyl, substituted or unsubstituted triazolyl, substituted or unsubstituted oxazolyl, substituted or unsubstituted thiazolyl, substituted or unsubstituted oxadiazolyl, substituted or unsubstituted thiadiazolyl, substituted or unsubstituted pyridyl, substituted or unsubstituted pyrimidinyl, substituted or unsubstituted pyrazinyl, substituted or unsubstituted triazinyl, substituted or unsubstituted benzofuranyl, substituted or unsubstituted benzothienyl, substituted or unsubstituted unsubstituted benzimidazolyl, substituted or unsubstituted indolyl, substituted or unsubstituted quinolyl, substituted or unsubstituted isoquinolyl, substituted or unsubstituted quinazolinyl, substituted or unsubstituted quinoxalinyl, substituted or unsubstituted naphthyridinyl, substituted or unsubstituted benzoxazinyl, substituted or unsubstituted benzothiazinyl, substituted or unsubstituted acridinyl, substituted or unsubstituted phenanthazinyl, substituted or unsubstituted phenathiazinyl, substituted or unsubstituted phenoxazinyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted dibenzothiophenyl, substituted or unsubstituted carbazolyl.

[0132] The substituted or unsubstituted C6-C 30 The arylene group refers to a substituted or unsubstituted phenylene group, a substituted or unsubstituted naphthylene group, a substituted or unsubstituted anthrylene group, or a substituted or unsubstituted phenanthrenyl group.

[0133] The substituted or unsubstituted C2-C 30The heteroarylene group refers to a substituted or unsubstituted furylene group, a substituted or unsubstituted thienylene group, a substituted or unsubstituted pyrrolylene group, a substituted or unsubstituted pyrazolylene group, a substituted or unsubstituted imidazolylene group, a substituted or unsubstituted triazolylene group, a substituted or unsubstituted oxazolylene group, a substituted or unsubstituted thiazolylene group, a substituted or unsubstituted oxadiazolylene group, a substituted or unsubstituted thiadiazolylene group, a substituted or unsubstituted pyridinylene group, a substituted or unsubstituted pyrimidinylene group, a substituted or unsubstituted pyrazinylene group, a substituted or unsubstituted triazinylene group, a substituted or unsubstituted benzofuranylene group, a substituted or unsubstituted benzothienylene group, a substituted or unsubstituted benzimidazolylene, substituted or unsubstituted indolylene, substituted or unsubstituted quinolinylene, substituted or unsubstituted isoquinolinylene, substituted or unsubstituted quinazolinylene, substituted or unsubstituted quinoxalinylene, substituted or unsubstituted naphthyridinylene, substituted or unsubstituted benzoxazinylene, substituted or unsubstituted benzothiazinylene, substituted or unsubstituted acridinylene, substituted or unsubstituted phenazinylene, substituted or unsubstituted phenathiazinylene, substituted or unsubstituted phenoxazinylene, substituted or unsubstituted dibenzofuranylene, substituted or unsubstituted dibenzothiophenylene, or substituted or unsubstituted carbazolylene.

[0134] In a preferred embodiment, Ar5, Ar6, and Ar7 are independently selected from the group consisting of substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted pyridyl, substituted or unsubstituted pyrimidinyl, substituted or unsubstituted dibenzothiophene, and substituted or unsubstituted quinolyl.

[0135] The L3 represents a single bond, a phenylene group, a biphenylene group or a naphthylene group;

[0136] The substituent for the substituent group is one or two of a deuterium atom, a phenyl group, a naphthyl group, a biphenyl group, a dibenzofuranyl group, a dibenzothienyl group, a pyridyl group, and a pyrimidyl group.

[0137] In a preferred embodiment of the present invention, the electron transport layer comprises any one of the following compounds:

[0138]

[0139] In a more preferred embodiment of the present invention, the electron transport layer comprises any one of the following compounds:

[0140]

[0141] In a preferred embodiment of the present invention, in addition to the compound of general formula (4), the electron transport layer further comprises other compounds conventionally used for electron transport layers, for example, Alq3, LiQ, preferably LiQ. In a more preferred embodiment of the present invention, the electron transport layer consists of one of the compounds of general formula (4) and one of the other compounds conventionally used for electron transport layers (preferably LiQ).

[0142] The hole injection and transport rates of the hole transport region containing the bisaromatic amine compound of the present invention can be well matched to the electron injection and transport rates. Preferably, the hole injection and transport rates of the hole transport region containing the bisaromatic amine compound of the present invention can be better matched to the electron injection and transport rates of the electron transport region containing the nitrogen heterocyclic derivative of general formula (4).

[0143] Therefore, in a particular embodiment of the present invention, an electron transport region comprising one or more nitrogen heterocyclic derivatives of the general formula (4) or consisting thereof is used in combination with a hole transport region comprising the diarylamine compound of the present invention to achieve relatively better technical effects.

[0144] The thickness of the electron transport layer of the present invention may be 10-80 nm, preferably 20-60 nm, and more preferably 25-45 nm, but the thickness is not limited to this range.

[0145] Covering

[0146] In order to improve the light extraction efficiency of the organic electroluminescent device, a light extraction layer (i.e., CPL layer, also called cover layer) can be added to the cathode of the device. According to the principles of optical absorption and refraction, the refractive index of the CPL cover layer material should be as high as possible, and the absorption coefficient should be as small as possible. Any material known in the art can be used as the CPL layer material, such as Alq3, or N4,N4'-diphenyl-N4,N4'-di(9-phenyl-3-carbazolyl)biphenyl-4,4'-diamine. The thickness of the CPL cover layer is generally 5-300 nm, preferably 20-100 nm and more preferably 40-80 nm.

[0147] The organic electroluminescent device of the present invention may further include an encapsulation structure. The encapsulation structure may be a protective structure that prevents foreign substances, such as moisture and oxygen, from entering the organic layer of the organic electroluminescent device. The encapsulation structure may be, for example, a can, such as a glass or metal can, or a thin film covering the entire surface of the organic layer.

[0148] Hereinafter, an organic electroluminescent device according to an embodiment of the present invention is described.

[0149] In the accompanying drawings, the thickness of layers, films, substrates, regions, etc., is exaggerated for clarity. Throughout the specification, like reference numerals denote like elements. It should be understood that when an element, such as a layer, film, region, or substrate, is referred to as being "on" another element, it can be directly on the other element or intervening elements may be present. In contrast, when an element is referred to as being "directly on" another element, there are no intervening elements present.

[0150] Figure 1 is a schematic cross-sectional view of an organic electroluminescent device according to an embodiment of the present invention.

[0151] See Figure 1 According to one embodiment of the present invention, the organic electroluminescent device includes an anode 2 and a cathode 10 facing each other, a hole transport region, a light-emitting layer 6 and an electron transport region sequentially arranged between the anode 2 and the cathode 10, and a substrate 1 under the anode 2 and a covering layer 11 above the cathode, wherein the hole transport region includes a hole injection layer 3, a hole transport layer 4 and an electron blocking layer 5, and the electron transport region includes a hole blocking layer 7, an electron transport layer 8 and an electron injection layer 9.

[0152] The present invention also relates to a method for preparing an organic electroluminescent device, comprising sequentially laminating an anode, a hole injection layer, a hole transport layer, an electron blocking layer, an organic film layer, an electron transport layer, an electron injection layer, and a cathode, and optionally a capping layer, on a substrate. In this regard, vacuum deposition, vacuum evaporation, spin coating, casting, LB method, inkjet printing, laser printing, or LITI methods may be used, but are not limited thereto. In the present invention, vacuum evaporation is preferably used to form the various layers. Those skilled in the art can conventionally select the various process conditions in the vacuum evaporation method according to actual needs.

[0153] In addition, it should be noted that the materials used to form each layer described in the present invention can be formed into a film alone and used as a single layer, or can be mixed with other materials to form a film and used as a single layer. It can also be a stacked structure between layers formed into films alone, a stacked structure between layers formed into films after mixing, or a stacked structure between layers formed into films alone and layers formed into films after mixing.

[0154] The present invention also relates to a full-color display device having three pixels (red, green, and blue) comprising the organic electroluminescent device of the present invention, particularly a flat-panel display device. The display device may further include at least one thin-film transistor. The thin-film transistor may include a gate electrode, a source electrode, a drain electrode, a gate insulating layer, and an active layer, wherein one of the source electrode and the drain electrode may be electrically connected to an anode of the organic electroluminescent device. The active layer may include, but is not limited to, crystalline silicon, amorphous silicon, an organic semiconductor, or an oxide semiconductor.

[0155] Preparation Example 1: Synthesis of Compound 27

[0156]

[0157] In a three-necked flask, under nitrogen, 0.01 mol of raw material A1 and 50 ml of tetrahydrofuran were added. The reaction vessel was cooled to -78°C with dry ice, and then n-butyl lithium (1.6 mol / L, 7.5 mL, 0.012 mol) was slowly added dropwise. The reaction was stirred for 1 hour, and 0.012 mol of raw material B1 was added. Stirring continued for 1 hour, and then the system was naturally warmed to room temperature and stirred for 3 hours. The sampling point plate showed no residual raw material A1, indicating complete reaction. The reaction was quenched with distilled water, extracted three times with 50 mL × 3 ether, and dehydrated with anhydrous magnesium sulfate. The filtrate was filtered and rotary evaporated until no fraction remained to obtain intermediate C1. The reaction was then transferred to a three-necked flask, filled with nitrogen, and 50 mL of acetic acid was added. The reaction was heated to 100°C, refluxed and stirred for 1 hour, and cooled naturally to room temperature. 50 mL of concentrated hydrochloric acid was slowly added dropwise until a solid precipitate appeared. The product was extracted with dichloromethane three times, dried over anhydrous magnesium sulfate, filtered, and the filtrate was evaporated to a complete residue. The product was then passed through a neutral silica gel column to obtain intermediate D27. LC-MS: Calculated value: 540.12; Measured value ([M+H] + ):541.33.

[0158] 0.01 mol of intermediate D27 and 0.012 mol of intermediate E1 were added to 120 mL of a mixed solvent of toluene:ethanol = 2:1 (volume ratio), 10 mL of a 2 mol / L sodium carbonate aqueous solution was added, and 5×10 - 5 mol Pd(PPh3)4, heated to 110°C for 6 hours, sampled, and after the reaction of intermediate D27 was complete, cooled naturally and filtered. The filtrate was distilled under reduced pressure to remove the solvent. The crude product was passed through a silica gel column to obtain intermediate F1; LC-MS: theoretical value: 781.35; measured value: 782.45 ([M+H] + ).

[0159] Add 0.01 mol of intermediate F1, 0.012 mol of raw material G1, and 100 mL of toluene and stir to mix. Then add 0.02 mol of sodium tert-butoxide, 1×10 -5 mol Pd2(dba)3,1×10 -5 mol tri-tert-butylphosphine, stirred and heated to 115 ° C, reflux reaction for 5 hours, sampling plate, showed that there was no raw material G1 remaining, the reaction was complete; naturally cooled to room temperature, filtered, the filtrate was vacuum evaporated until there was no fraction, and passed through a neutral silica gel column to obtain compound 27; elemental analysis molecular formula (C 69 H 58N2), theoretical value: C, 90.55; H, 6.39; N, 3.06; found value: C, 90.53; H, 6.35; N, 3.08. LC-MS: theoretical value: 914.46; found value ([M+H] + ):915.41.

[0160] The preparation process in Preparation Example 1 was repeated to synthesize the following target compound; the reaction conditions were the same, except that the intermediate D, intermediate E and raw material G listed in Table 1 below were used; detailed characterization data are shown in Table 1.

[0161] Table 1

[0162]

[0163]

[0164]

[0165]

[0166] Synthesis of intermediate D3

[0167]

[0168] In a three-necked flask, under nitrogen, 0.01 mol of raw material A3 and 50 ml of tetrahydrofuran were added. The reaction vessel was cooled to -78°C with dry ice, and then n-butyl lithium (1.6 mol / L, 7.5 mL, 0.012 mol) was slowly added dropwise. The reaction was stirred for 1 hour, and 0.012 mol of raw material B1 was added. Stirring continued for 1 hour, and then the system was naturally warmed to room temperature and stirred for 3 hours. The sampling point plate showed that there was no residual raw material A3, indicating complete reaction. The reaction was quenched with distilled water, and extracted three times with 50 mL × 3 ether. The water was removed with anhydrous magnesium sulfate, filtered, and the filtrate was rotary evaporated until no fraction was left to obtain intermediate C3. The reaction was then transferred to a three-necked flask, filled with nitrogen, and 50 mL of acetic acid was added. The reaction was heated to 100°C, refluxed and stirred for 1 hour, and cooled to room temperature. 50 mL of concentrated hydrochloric acid was slowly added dropwise until a solid precipitate appeared. The product was extracted with dichloromethane three times, dried over anhydrous magnesium sulfate, filtered, and the filtrate was evaporated to a complete residue. The product was then passed through a neutral silica gel column to obtain intermediate D3. LC-MS: Calculated value: 417.98; Measured value ([M+H] + ):418.87.

[0169] Synthesis of intermediate E6

[0170]

[0171] 0.01 mol of raw material H6 and 0.012 mol of raw material J6 were added to 120 mL of a mixed solvent of toluene:ethanol = 2:1 (volume ratio), 10 mL of a 2 mol / L sodium carbonate aqueous solution was added, and 5×10 -5 mol Pd(PPh3)4, heated to 110°C for 8 hours, sampled, and after the reaction of raw material H6 was complete, cooled naturally and filtered. The filtrate was distilled under reduced pressure to remove the solvent. The crude product was passed through a silica gel column to obtain intermediate K6; LC-MS: theoretical value: 341.98; measured value: 342.84 ([M+H] + ).

[0172] Add 0.01 mol of intermediate K6, 0.012 mol of raw material L6, and 100 mL of toluene and stir to mix. Then add 0.02 mol of sodium tert-butoxide, 1×10 -5 mol Pd2(dba)3,1×10 -5 mol tri-tert-butylphosphine, stirred and heated to 115°C, refluxed for 12 hours, sampled and plated, showing no intermediate K6 remaining, indicating complete reaction; cooled naturally to room temperature, filtered, and the filtrate was evaporated under reduced pressure until no fraction remained, and passed through a neutral silica gel column to obtain intermediate M6; LC-MS: theoretical value: 481.16; measured value: 482.27 ([M+H] + )

[0173] 0.01 mol intermediate M6, 0.02 mol biboric acid pinacol ester (raw material N6), 0.03 mol potassium acetate, 5×10 -5 mol Pd(dppf)Cl2 and 100 mL 1,4-dioxane were stirred and mixed, heated to 80°C, and reacted for 6 hours. A sample plate was taken, indicating that no intermediate M6 remained, indicating that the reaction was complete. The mixture was cooled naturally to room temperature, and solid precipitated after adding water. The solid was filtered, and the filter cake was dried in a vacuum drying oven and then passed through a neutral silica gel column to obtain the boronate intermediate E6. LC-MS: theoretical value: 573.28; measured value ([M+H] + ):574.34.

[0174] The preparation process of intermediate E6 was repeated to synthesize the following target compounds; the reaction conditions were the same except that the starting materials listed in Table 2 below were used; detailed characterization data are shown in Table 2.

[0175] Table 2

[0176]

[0177]

[0178] Preparation method of comparative compound HT-1:

[0179]

[0180] In a three-necked flask, under nitrogen protection, 0.012 mol of intermediate D1, 0.01 mol of raw material G1, and 150 ml of toluene were added and stirred, and then 5×10 -5 mol Pd2(dba)3,5×10 -5 mol tri-tert-butylphosphine, 0.03 mol sodium tert-butoxide, heated to 105°C, refluxed for 24 hours, sampled, and the plate showed no amino compound remaining, indicating complete reaction; cooled naturally to room temperature, filtered, and the filtrate was rotary evaporated until no fraction remained, and passed through a neutral silica gel column to obtain intermediate S1. LC-MS ([M+H] + ): The measured value is 518.22.

[0181] Under nitrogen atmosphere, 0.06 mol of intermediate S1 was added to a three-necked flask, and a mixed solvent (300 ml toluene, 90 ml H2O) was added to dissolve it, and the mixture was stirred for 1 hour under nitrogen. Then, 0.05 mol of raw material S2, 0.1 mol K2CO3, and 0.005 mol Pd(PPh3)4 were slowly added, and the mixture was heated to 90°C and reacted for 8 hours. The reaction was observed by thin layer chromatography (TLC) until the reaction was complete. After naturally cooling to room temperature, water was added to the reaction system for extraction, and the liquid was separated. The organic phase was subjected to reduced pressure rotary evaporation until there was no fraction. The obtained substance was purified by silica gel column to obtain the target product. Elemental analysis structure (molecular formula C 55 H 38 N2): Found: C, 90.87; H, 5.25; N, 3.86. LC-MS ([M+H] + ): The measured value is 727.39.

[0182] The preparation of the comparative compound HT-5 refers to the preparation method of the comparative compound HT-1 above

[0183] Structural characterization of comparative compound HT-5: LC-MS ([M+H] + ): Found value is 803.15; Elemental analysis found value: C, 91.29; H, 5.24; N, 3.47.

[0184] Note: To facilitate the listing of raw materials corresponding to preparation examples and intermediates, the same compound will be represented by different codes in different reaction systems.

[0185] Detection method

[0186] Glass transition temperature Tg: measured by differential scanning calorimetry (DSC, DSC204F1 differential scanning calorimeter, NETZSCH, Germany) with a heating rate of 10°C / min.

[0187] HOMO energy level: tested by ionization energy test system (IPS3) in a vacuum environment.

[0188] Eg energy level: tested by a double-beam UV-visible spectrophotometer (Model: TU-1901). Based on the UV spectrophotometry (UV absorption) baseline of the material single film and the rising side of the first absorption peak, a tangent is drawn and the value of the intersection of the tangent and the baseline is calculated.

[0189] Hole mobility: The material is made into a single-charge device and measured using the space charge limited current method (SCLC).

[0190] Triplet energy level T1: tested by Horiba's Fluorolog-3 series fluorescence spectrometer, the material testing conditions are 2×10 -5 mol / L toluene solution.

[0191] The specific physical property test results are shown in Table 3.

[0192] Table 3

[0193]

[0194] It can be seen from the data in Table 3 above that the compounds of the present invention have suitable HOMO energy levels, higher hole mobility and wider band gap (Eg).

[0195] Preparation of organic electroluminescent devices

[0196] The molecular structures of the materials involved in the following preparation process are shown below:

[0197]

[0198] Device Comparative Example 1

[0199] The organic electroluminescent device was prepared by the following steps:

[0200] like Figure 1As shown, the substrate layer 1 is washed, followed by the anode layer 2 (Ag (100nm)), which is sequentially washed with alkaline, then washed with pure water, and dried. Finally, a UV-ozone wash is performed to remove organic residues from the anode layer surface. On the washed anode layer 2, a 10nm thick layer of HT-1 and P-1 is deposited using a vacuum evaporation apparatus as the hole injection layer 3, with a mass ratio of HT-1 to P-1 of 97:3. HT-1 is then evaporated to a thickness of 117nm as the hole transport layer 4. EB-1 is then evaporated to a thickness of 10nm as the electron blocking layer 5. After the electron blocking material deposition is completed, the light-emitting layer 6 of the OLED light-emitting device is fabricated. Its structure includes BH-1 as the host material and BD-1 as the dopant material, with a dopant ratio of 3% by weight. The light-emitting layer has a thickness of 20nm. Following the light-emitting layer 6, HB1 is evaporated to a thickness of 8nm as the hole blocking layer 7. On top of the hole blocking layer 7, ET-1 and Liq were further evaporated, with the ET-1 and Liq mass ratio being 1:1. The vacuum-evaporated film thickness of this material was 30 nm, and this layer served as the electron transport layer 8. On the electron transport layer 8, a 1 nm thick LiF layer was formed using a vacuum evaporation device. This layer served as the electron injection layer 9. On the electron injection layer 9, a 16 nm thick Mg:Ag electrode layer was formed using a vacuum evaporation device. The Mg:Ag mass ratio was 1:9. This layer served as the cathode layer 10. On the cathode layer 10, 70 nm of CP-1 was vacuum-evaporated as the capping layer 11.

[0201] Device Comparative Examples 2-5

[0202] The method of device comparative example 1 was followed, except that the organic materials in the hole injection layer and the hole transport layer were replaced with the organic materials shown in Table 4, respectively.

[0203] Device Examples 1-24

[0204] The method of device comparative example 1 was followed, except that the organic materials in the hole injection layer, the hole transport layer or the electron transport layer were replaced with the organic materials shown in Table 4, respectively.

[0205] Table 4

[0206]

[0207]

[0208] In the table above, taking Example 1 as an example, the second column "P-1: Compound 1 = 3:97 10 nm" indicates that the hole injection layer is made of P-type dopant material P-1 and Compound 1, 3:97 refers to the weight ratio of the P-type dopant material to Compound 1 being 3:97, and 10 nm represents the thickness of the layer. The third column "Compound 1 117 nm" indicates that the material used is Compound 1 and the thickness of the layer is 117 nm. Similarly, the meanings in other tables can be deduced.

[0209] After the OLED light-emitting device is prepared as described above, the cathode and anode are connected using a known driving circuit, and various performances of the device are measured.

[0210] The device performance measurement results of Examples 1-24 and Comparative Examples 1-4 are shown in Table 5.

[0211] Table 5

[0212]

[0213]

[0214] Note: LT95 refers to the time it takes for the device brightness to decay to 95% of its original brightness when the brightness is 1500nits.

[0215] The voltage, current efficiency, and color coordinates were measured using an IVL (current-voltage-luminance) test system (Suzhou Fushida Scientific Instrument Co., Ltd.); the current density was 10 mA / cm 2 ;

[0216] The life test system is the EAS-62C OLED life test system produced by Japan System Research Co., Ltd.

[0217] High temperature life refers to the device's life at 80°C and a current density of 10mA / cm 2 The time it takes for the device brightness to decay to 80% of its original brightness under irradiance;

[0218] From the results of Comparative Examples 2-4 and Device Examples 1-24 in Table 5, it can be seen that the use of the diaromatic amine organic compounds of the present invention as hole injection and hole transport layer materials has a higher carrier transfer rate, which effectively reduces the voltage of the device and improves the device efficiency and device life. Compared with Comparative Examples 1 and 5, the efficiency of Device Examples 1-24 is improved by more than 4% while maintaining a certain life and high-temperature life. In particular, in Examples 21-24, the structure of the present invention is used in combination with a specific electron transport layer material. This combination significantly improves the high-temperature life of the device.

Claims

1. A diarylamine organic compound, characterized in that: The structure of the compound is shown in general formula (1): In the general formula (1), a and c are independently represented by the numbers 0 or 1, and a+c=1 or 2; R1 to R4 are independently represented by a hydrogen atom, a deuterium atom, a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group, a substituted or substituted furyl group, a substituted or unsubstituted thienyl group, a substituted or unsubstituted benzothienyl group, a substituted or unsubstituted dibenzothienyl group, a substituted or unsubstituted benzofuranyl group, or a substituted or unsubstituted dibenzofuranyl group, and R1 to R4 are connected to the general formula (1) in two ways: substitution and cyclization. Ar1 to Ar8 are independently represented by a hydrogen atom, a deuterium atom, a substituted or unsubstituted phenyl group, a substituted or unsubstituted naphthyl group or a substituted or unsubstituted biphenyl group, and at least one of Ar1 to Ar8 is not represented by a hydrogen atom or a deuterium atom; The substituents for the above substitutable groups are selected from deuterium atoms, methyl groups, ethyl groups, tert-butyl groups, phenyl groups, biphenyl groups or naphthyl groups; The m, n, p, and q are independently represented by the numbers 0, 1, 2, 3, 4, or 5; Said Ar is represented by the general formula (2); In the general formula (2), the "---" indicates no bond; Said A is represented by the structure shown in general formula (3), general formula (4) or general formula (5); Said X represents an oxygen atom or a sulfur atom; The R0, R a and R b Each independently represents a hydrogen atom, a deuterium atom, a methyl group, an ethyl group, an isopropyl group, a tert-butyl group, a phenyl group, a naphthyl group or a biphenyl group; Wherein, "*" indicates that the general formulas (2) to (5) can be combined with the general formula (1). When general formula (3) to general formula (5) are respectively cyclic with general formula (2), the two carbon atoms at the cyclic position cannot be cyclic with Groups connected.

2. The diarylamine organic compound according to claim 1, characterized in that The structure of the compound is shown in general formula (2-1): In the general formula (2-1), the meanings of R1-R4, Ar, Ar1-Ar4, m, n, p, and q are the same as those defined in claim 1, and at least one of Ar1 to Ar4 is not a hydrogen atom or a deuterium atom.

3. The diarylamine organic compound according to claim 1, characterized in that The structures of the compounds are shown in general formula (2-2) to general formula (2-3): In general formula (2-2) and general formula (2-3), Ar1 and Ar2 are independently represented by substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl or substituted or unsubstituted biphenyl, and the meanings of R1-R4, Ar, m, n, p, and q are the same as those defined in claim 1.

4. The diarylamine organic compound according to claim 1, characterized in that The compounds are shown in general formulas (3-1) to (3-12); In general formula (3-1) to general formula (3-12), the meanings of R1-R4, Ar, m, n, p, and q are the same as those defined in claim 1.

5. The diarylamine organic compound according to claim 1, characterized in that The compounds are shown in general formula (4-1) to general formula (4-4); In the general formula (4-1) to the general formula (4-4), Ar1 and Ar2 are independently represented by substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl or substituted or unsubstituted biphenyl, and R1-R4, R a , A, m, n, p, q have the same meanings as those defined in claim 1.

6. The diarylamine organic compound according to claim 1, characterized in that The compounds are shown in general formula (5-2), general formula (5-4) and general formula (5-7); In the general formula (5-2), the general formula (5-4) and the general formula (5-7), Ar1 and Ar2 are independently represented by substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl or substituted or unsubstituted biphenyl, and R1-R4, R a 、R b , m, n, p, q have the same meanings as those defined in claim 1.

7. The diarylamine organic compound according to claim 1, characterized in that The specific structure of the compound is any one of the following structures:

8. An organic electroluminescent device comprising, in sequence, an anode, a hole transport region, a light emitting region, an electron transport region, and a cathode, characterized in that: The hole transport region comprises the bisarylamine organic compound according to any one of claims 1 to 7.

9. The organic electroluminescent device according to claim 8, characterized in that: The hole transport region comprises a hole injection layer, a first hole transport layer and a second hole transport layer, wherein the first hole transport layer and the hole injection layer comprise the diarylamine organic compound according to any one of claims 1 to 7; Preferably, the hole transport layer comprises the diarylamine organic compound according to any one of claims 1 to 7, and the hole injection layer consists of the diarylamine organic compound according to any one of claims 1 to 7 and a P-type doping material for the hole injection layer.

10. The organic electroluminescent device according to claim 8, characterized in that: The electron transport region comprises a nitrogen heterocyclic compound represented by the general formula (10-1): In the general formula (10-1), Ar5, Ar6, and Ar7 are independently selected from substituted or unsubstituted C6-C 30 Aryl, substituted or unsubstituted C2-C 30 One of the heterocyclic groups; L3 represents a single bond, a substituted or unsubstituted C6-C 30 Arylene, substituted or unsubstituted C2-C 30 A heterocyclylene group; X1, X2, and X3 independently represent N or CH, and at least one of X1, X2, and X3 represents N; The heteroatoms are each independently selected from N, O or S; The substituent for the substituted group is one or more of a deuterium atom, a phenyl group, a naphthyl group, a biphenyl group, a dibenzofuranyl group, a dibenzothienyl group, a pyridyl group or a pyrimidyl group.

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