An aromatic amine-based organic compound and an organic electroluminescent device comprising the same

Abstract

The application discloses an aromatic amine organic compound and an organic electroluminescent device containing the same, and belongs to the technical field of semiconductor materials. The structure of the aromatic amine organic compound is shown in general formula (1). The aromatic amine organic compound has excellent hole mobility and exciton blocking capacity under high current density. When the aromatic amine organic compound is used to form a light-emitting auxiliary layer material of an organic electroluminescent device, the device efficiency is improved and the device life is prolonged.

Description

Technical Field

[0001] This invention relates to the field of semiconductor materials technology, and more particularly to an aromatic amine compound and an organic electroluminescent device containing the same. Background Technology

[0002] Organic light-emitting diodes (OLEDs) can be used to manufacture novel display products and lighting products, and are expected to replace existing liquid crystal displays and fluorescent lighting, with a very wide range of applications. OLEDs have a sandwich-like structure, consisting of electrode material layers and organic functional materials sandwiched between these layers. These various organic functional materials are stacked together according to their intended use to form the OLED. As a current-carrying device, when a voltage is applied to the two electrodes of the OLED, and an electric field is used to act on the positive and negative charges in the organic functional material layers, these charges recombine in the light-emitting layer, thus generating organic light emission.

[0003] Currently, organic light-emitting diode (OLED) display technology has been applied in smartphones, tablets, and televisions. However, compared with the requirements of actual product applications, the luminous efficiency and lifespan of OLED devices still need further improvement. Research on improving the performance of OLED devices includes reducing the driving voltage, increasing luminous efficiency, and extending lifespan. To continuously improve the performance of OLED devices, it is necessary not only to innovate the structure and manufacturing process of OLED devices, but also to continuously research and innovate organic functional materials to create higher-performance organic functional materials.

[0004] Blue organic light-emitting diodes (OLEDs) have always been a weak point in the development of full-color OLEDs. To date, the efficiency and lifespan of blue light-emitting devices have been difficult to improve comprehensively. Therefore, improving the performance of blue light-emitting devices remains a crucial issue and challenge in this field. Currently, most blue light-emitting host materials used in the market are electron-biased. At low current densities, preferential hole injection alleviates the pressure on the hole transport side to some extent. However, as the current density increases, the amount of electron injection increases, causing the recombination region to shift towards the hole side, increasing the pressure on the hole side. To prevent excitons from being transferred to the hole side, the luminescent auxiliary layer material must effectively block excitons and efficiently transport holes to the luminescent layer. Currently, most luminescent auxiliary layer materials are traditional aromatic amine structures. The electron tolerance of these structures in existing technologies still cannot meet the requirements. The hole mobility at high current densities needs to be improved to ensure carrier balance in the luminescent layer and prevent the recombination region from shifting towards the hole transport side due to insufficient holes, leading to reduced device efficiency and shorter lifespan. Summary of the Invention

[0005] To address the aforementioned problems in the prior art, this invention provides an aromatic amine organic compound and an organic electroluminescent device containing the same. The aromatic amine organic compound of this invention is used as a light-emitting auxiliary layer in an organic electroluminescent device, which can effectively improve the lifespan and efficiency of the organic electroluminescent device.

[0006] The present invention provides the following technical solution: an aromatic amine organic compound, the structure of which is shown in general formula (1):

[0007]

[0008] General formula (1)

[0009] In general formula (1), Ar1 and Ar2 represent C6-C atoms substituted or unsubstituted with substituents, respectively. 30 aryl or C2-C 30 heteroaryl groups;

[0010] L1 and L2 represent a single bond, a phenylene group substituted or unsubstituted with a substituent, a naphthylene group substituted or unsubstituted with a substituent, and a diphenylene group substituted or unsubstituted with a substituent, respectively.

[0011] The substituent is selected from one or more of the following: deuterium atom, methyl, ethyl, tert-butyl, phenyl, naphthyl, and diphenyl.

[0012] Any hydrogen atom in general formula (1) can be replaced by a deuterium atom.

[0013] Furthermore, the structure of the aromatic amine organic compound is shown in any one of general formulas (1A) to (1D):

[0014]

[0015] General Formula (1A) General Formula (1B)

[0016]

[0017] General Formula (1C) General Formula (1D)

[0018] In general formulas (1A) to (1D), the meanings of L1, L2, Ar1 and Ar2 are the same as those defined in general formula (1) above.

[0019] Furthermore, the structure of the aromatic amine organic compound is shown in any one of general formulas (1-1) to (1-12):

[0020] General formula (1-1) General formula (1-2)

[0021] General formula (1-3) General formula (1-4)

[0022] General formula (1-5) General formula (1-6)

[0023] General formula (1-7) General formula (1-8)

[0024] General formula (1-9) General formula (1-10)

[0025] General formula (1-11) General formula (1-12)

[0026] In general formulas (1-1) to (1-12), the meanings of L2 and Ar2 are the same as those defined in general formula (1) above.

[0027] Furthermore, the structure of the aromatic amine organic compound is shown in any one of general formulas (2-1) to (2-12):

[0028] General formula (2-1) General formula (2-2)

[0029] General formula (2-3) General formula (2-4)

[0030] General formula (2-5) General formula (2-6)

[0031] General formula (2-7) General formula (2-8)

[0032] General formula (2-9) General formula (2-10)

[0033] General formula (2-11) General formula (2-12)

[0034] In general formulas (2-1) to (2-12), the meanings of L2 and Ar2 are the same as those defined in general formula (1) above.

[0035] Furthermore, the structure of the aromatic amine organic compound is shown in any one of general formulas (3-1) to (3-10):

[0036] General formula (3-1) General formula (3-2)

[0037] General formula (3-3) General formula (3-4)

[0038] General formula (3-5) General formula (3-6)

[0039] General formula (3-7) General formula (3-8)

[0040] General formula (3-9) General formula (3-10)

[0041] In general formulas (3-1) to (3-10), X is an oxygen atom or a sulfur atom, and the meanings of L2 and Ar2 are the same as those defined in general formula (1) above.

[0042] Furthermore, the structure of the aromatic amine organic compound is shown in any one of general formulas (4-1) to (4-8):

[0043] General formula (4-1) General formula (4-2)

[0044] General formula (4-3) General formula (4-4)

[0045] General formula (4-5) General formula (4-6)

[0046] General formula (4-7) General formula (4-8)

[0047] In general formulas (4-1) to (4-8), the meanings of L2 and Ar2 are the same as those defined in general formula (1) above.

[0048] Furthermore, the structure of the aromatic amine organic compound is shown in any one of general formulas (5-1) to (5-4):

[0049] General formula (5-1) General formula (5-2)

[0050] General formula (5-3) General formula (5-4).

[0051] Further, Ar1 and Ar2 respectively represent phenyl (substituted or unsubstituted), naphthyl (substituted or unsubstituted), diphenyl (substituted or unsubstituted), dibenzofuranyl (substituted or unsubstituted), dibenzothiopheneyl (substituted or unsubstituted), naphthobenzofuranyl (substituted or unsubstituted), naphthobenzothiopheneyl (substituted or unsubstituted), phenanthreneyl (substituted or unsubstituted), triphenylene (substituted or unsubstituted), and furanyl (substituted or unsubstituted). The group includes thiophene group (substituted or unsubstituted), indol group (substituted or unsubstituted), carbazolyl group (substituted or unsubstituted), benzocarbazolyl group (substituted or unsubstituted), fluorenyl group (substituted or unsubstituted), dimethylfluorenyl group (substituted or unsubstituted), diphenylfluorenyl group (substituted or unsubstituted), spirofluorenyl group (substituted or unsubstituted), silanyl fluorenyl group (substituted or unsubstituted), and spirosilanyl fluorenyl group (substituted or unsubstituted), wherein the substitution of the substituent is either single bond substitution or cyclic substitution.

[0052] L1 and L2 respectively represent a single bond, a phenylene group substituted or unsubstituted with a substituent, a naphthylene group substituted or unsubstituted with a substituent, and a diphenylene group substituted or unsubstituted with a substituent;

[0053] The substituent is selected from one or more of the following: deuterium atom, methyl, ethyl, tert-butyl, phenyl, naphthyl, and diphenyl.

[0054] Furthermore, L1 and L2 represent single bonds or the following structures:

[0055] , , , , , , , , , , Any one of them;

[0056] Ar1 and Ar2 are each independently represented by the following structures:

[0057] , , , , , , , 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 , , , , , , , , , , , , Any one of them; * indicates a connection site.

[0058] Furthermore, the structure of the aromatic amine organic compound is selected from any one of the following structural formulas:

[0059] (1) (2) (3) (4)

[0060] (5) (6) (7) (8)

[0061] (9) (10) (11) (12)

[0062] (13) (14) (15) (16)

[0063] (17) (18) (19) (20)

[0064] (twenty one) (twenty two) (twenty three) (twenty four)

[0065] (25) (26) (27) (28)

[0066] (29) (30) (31) (32)

[0067] (33) (34) (35) (36)

[0068] (37) (38) (39) (40)

[0069] (41) (42) (43) (44)

[0070] (45) (46) (47) (48)

[0071] (49) (50) (51) (52)

[0072] (53) (54) (55) (56)

[0073] (57) (58) (59) (60)

[0074] (61) (62) (63) (64)

[0075] (65) (66) (67) (68)

[0076] (69) (70) (71) (72)

[0077] (73) (74) (75) (76)

[0078] (77) (78) (79) (80)

[0079] (81) (82) (83) (84)

[0080] (85) (86) (87) (88)

[0081] (89) (90) (91) (92)

[0082] (93) (94) (95) (96)

[0083] (97) (98) (99) (100)

[0084] (101) (102) (103) (104)

[0085] (105) (106) (107) (108)

[0086] (109) (110) (111) (112)

[0087] (113) (114) (115) (116)

[0088] (117) (118) (119) (120)

[0089] (121) (122) (123) (124)

[0090] (125) (126) (127) (128)

[0091] (129) (130) (131) (132)

[0092] (133) (134) (135) (136)

[0093] (137) (138) (139) (140)

[0094] (141) (142) (143) (144)

[0095] (145) (146) (147) (148)

[0096] (149) (150) (151) (152)

[0097] (153) (154) (155) (156)

[0098] (157) (158) (159) (160)

[0099] (161) (162) (163) (164)

[0100] (165) (166) (167) (168)

[0101] (169) (170) (171) (172)

[0102] (173) (174) (175) (176)

[0103] (177) (178) (179) (180)

[0104] (181) (182) (183) (184)

[0105] (185) (186) (187) (188)

[0106] (189) (190) (191) (192)

[0107] (193) (194) (195) (196)

[0108] (197) (198) (199) (200)

[0109] (201) (202) (203) (204)

[0110] (205) (206) (207) (208)

[0111] (209) (210).

[0112] The present invention also provides an organic electroluminescent device, comprising a substrate, a first electrode, an organic functional layer, and a second electrode, wherein the organic functional layer contains the aromatic amine organic compound described in the present invention;

[0113] Preferably, the organic functional layer includes a hole transport region, a light-emitting region, and an electron transport region, wherein the hole transport region contains the aromatic amine organic compound described in this invention.

[0114] Furthermore, the hole transport region includes a hole injection layer, a hole transport layer, and a light-emitting auxiliary layer, wherein the light-emitting auxiliary layer contains the aromatic amine organic compound described in this invention.

[0115] Compared with the prior art, the beneficial technical effects of the present invention are as follows:

[0116] The aromatic amine organic compounds of this invention have a combination of specific group types, exhibiting excellent exciton blocking ability and hole mobility at high current density. They are used as light-emitting auxiliary layers in organic electroluminescent devices, thereby improving device efficiency and device lifespan.

[0117] Furthermore, the structural features of the organic compounds in this invention are beneficial for increasing the glass transition temperature of the molecules and for reducing the vapor deposition temperature of the molecules. In other words, even if the molecular weight of the structure is relatively high, it can still ensure a low vapor deposition temperature. This excellent performance is beneficial for the thermal vapor deposition of the material, controlling the thermal decomposition rate of the material, thereby improving the stability of the material in device applications. Attached Figure Description

[0118] Figure 1 This is a schematic diagram of the organic electroluminescent device described in the embodiment;

[0119] Figure 1In the diagram, 1. Glass substrate layer; 2. Anode layer; 3. Hole injection layer; 4. Hole transport layer; 5. Light emission auxiliary layer; 6. Light emission layer; 7. Hole blocking layer; 8. Electron transport layer; 9. Electron injection layer; 10. Cathode layer; 11. CPL layer.

[0120] Figure 2 The image shows the 1H NMR spectrum of compound 115. Detailed Implementation

[0121] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention.

[0122] In this invention, when a layer or element is referred to as being "above" another layer or substrate, the layer or element may be located directly above the other layer or substrate, or there may be intermediate layers. 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 there may be one or more intermediate layers.

[0123] In this invention, the terms "upper," "lower," "top," and "bottom," used to describe electrodes, organic electroluminescent devices, and other structures, indicate orientation only in a specific state and do not imply that the structure can only exist in that orientation. Conversely, if the structure can be repositioned, such as by inverting it, the orientation of the structure changes accordingly. Specifically, in this invention, the "bottom" or "lower" side of the electrode refers to the side of the electrode closer to the substrate during fabrication, while the opposite side farther from the substrate is the "top" or "upper" side.

[0124] In this specification, the term "substitution" means that one or more hydrogen atoms on a specified atom or group are replaced by a specified group, provided that the normal valence of the specified atom is not exceeded under the existing conditions.

[0125] In this specification, hole characteristics refer to the characteristics that allow holes formed in the anode to be easily injected into and transported in the light-emitting layer when an electric field is applied, due to conductivity characteristics at the highest occupied molecular orbital (HOMO) level.

[0126] In this specification, electronic characteristics refer to the characteristics that allow electrons formed in the cathode to be readily injected into and transported in the light-emitting layer when an electric field is applied, and which are attributed to conductivity characteristics based on the lowest unoccupied molecular orbital (LUMO) level.

[0127] The organic electroluminescent device of the present invention can be a bottom-emitting organic electroluminescent device, a top-emitting organic electroluminescent device, or a multilayer organic electroluminescent device, and there is no specific limitation thereto.

[0128] The organic electroluminescent device of the present invention comprises, in sequence, a substrate, a first electrode, an organic functional layer, and a second electrode. The organic functional layer includes a hole transport region, a light-emitting region, and an electron transport region. The hole transport region includes a hole injection layer, a hole transport layer, and a light-emitting auxiliary layer. The electron transport region includes a hole blocking layer, an electron transport layer, and an electron injection layer. Additionally, a CPL layer may be disposed on the second electrode.

[0129] The first electrode can be either an anode or a cathode, and the second electrode can be either a cathode or an anode.

[0130] In the organic electroluminescent device of this invention, any substrate commonly used in organic electroluminescent devices can be used. 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 different mechanical strengths, thermal stability, transparency, surface smoothness, and water resistance. Their application varies depending on their properties. In this invention, a transparent glass substrate is preferred. There are no particular limitations on the thickness of the substrate.

[0131] anode:

[0132] In this invention, an anode can be formed on a substrate. The anode and cathode are opposite each other. The anode can be made of a conductor with a high work function to facilitate hole injection, and can be, for example, a metal such as nickel, platinum, copper, zinc, silver or alloys thereof; a metal oxide such as zinc oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO); a combination of metal and 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, typically 50-500 nm, preferably 70-300 nm, and more preferably 100-200 nm, and in this invention, metallic Ag is preferred.

[0133] cathode:

[0134] The cathode can be made of a conductor with a low work function to facilitate electron injection, and can be, for example, a metal or alloy thereof, such as magnesium, calcium, sodium, potassium, titanium, indium, aluminum, silver, tin, and combinations thereof; multilayer materials, such as LiF / Al, Li₂O / Al, and BaF₂ / Ca, Mg / Ag, but not limited thereto. The thickness of the cathode depends on the material used, typically 10-50 nm, preferably 15-20 nm.

[0135] Emitting area:

[0136] In this invention, the light-emitting region can be disposed between the anode and the cathode, and can include at least one host material and at least one guest material. Both the host material and the guest material of the light-emitting region in the organic electroluminescent device of this invention can be light-emitting layer materials known in the prior art for organic electroluminescent devices.

[0137] In a preferred embodiment of the present invention, the luminescent region contains one or two host material compounds.

[0138] In a preferred embodiment of the present invention, the host material of the luminescent region is selected from one or more of the following compounds BH1-BH6:

[0139] (BH1) (BH2) (BH3)

[0140] (BH4) (BH5) (BH6).

[0141] In this invention, the luminescent region may contain phosphorescent or fluorescent guest materials to improve the fluorescence or phosphorescence properties of the organic electroluminescent device. Specific examples of phosphorescent guest materials include metal complexes of iridium, platinum, etc., while those commonly used in the art can be used for fluorescent guest materials. In a preferred embodiment of this invention, the guest material used in the luminescent film layer is selected from one of the following compounds BD1 to BD7:

[0142] (BD1) (BD2) (BD3)

[0143] (BD4) (BD5) (BD6)

[0144] (BD7)

[0145] In the light-emitting region of the present invention, the ratio of the host material to the guest material is 99:1-70:30, preferably 99:1-85:15 and more preferably 97:3-87:13, based on mass.

[0146] The thickness of the luminescent region can be 10-50 nm, preferably 15-30 nm, but the thickness is not limited to this range.

[0147] Hole transport region:

[0148] In the organic electroluminescent device of the present invention, a hole transport region is disposed between the anode and the light-emitting region, and includes a hole injection layer, a hole transport layer and a light-emitting auxiliary layer.

[0149] Hole injection layer:

[0150] The hole injection material used in the hole injection layer (also known as the anode interface buffer layer) is a material capable of fully accepting holes from the anode at low voltages, 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 invention, the hole injection layer is a mixed film layer of a host organic material and a p-type dopant. For holes to be smoothly injected from the anode into the organic film layer, the HOMO energy level of the host organic material must possess certain characteristics with the p-type dopant to facilitate charge transfer states between the host and dopant materials, achieving ohmic contact between the hole injection layer and the anode, thereby achieving efficient hole injection from the electrode to the hole injection layer. This characteristic is summarized as follows: the difference between the HOMO energy level of the host material and the LUMO energy level of the p-type dopant ≤ 0.4 eV. Therefore, for hole-type host organic 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.

[0151] Preferably, the main organic material is an aromatic amine organic compound, but it is not limited thereto.

[0152] Preferably, the p-type doped material is a charge-conducting compound disclosed in the prior art, and the p-type dopant can be selected from compounds disclosed in the following patent documents: WO2011073149A, EP1968131A1, EP2276085A1, EP2213662A1, EP1722602A1, EP2045848A1, DE102007031220A. 1. US20100181555A1, US20100102709A1, WO2009003455A1, WO2010094378A1, WO2011120709A1, US20100096600A1, DE102012209523A1, CN101728485A and WO2012095143A1, but not limited to these.

[0153] In a preferred embodiment of the present invention, the p-type doped material used is selected from any one of the following compounds HI1 to HI8:

[0154] HI1 HI2 HI3

[0155] HI4 HI5 HI6

[0156] HI7 HI8.

[0157] In one embodiment of the present invention, the ratio of the host organic material to the P-type doped material is 99:1-95:5, preferably 99:1-97:3, based on mass.

[0158] In a preferred embodiment of the present invention, the hole injection layer is a mixed film layer of aromatic amine organic compounds and p-type doped materials.

[0159] The thickness of the hole injection layer of the present invention can be 5-20 nm, preferably 8-15 nm, but the thickness is not limited to this range.

[0160] Hole transport layer:

[0161] In the organic electroluminescent device of the present invention, a hole transport layer may be disposed above a hole injection layer. The hole transport material is a suitable material with high hole mobility, capable of accepting holes from the anode or hole injection layer and transporting the holes to the light-emitting layer. Specific examples include, but are not limited to, aromatic amine organic materials, conductive polymers, and block copolymers having both conjugated and non-conjugated portions. In a preferred embodiment, the hole transport layer comprises the same aromatic amine organic compound as the hole injection layer.

[0162] Preferably, the hole transport layer material of the present invention may be selected from the compounds disclosed in the prior art:

[0163]

[0164] The thickness of the hole transport layer of the present invention can be 80-200 nm, preferably 100-200 nm, more preferably 100-150 nm, but the thickness is not limited to this range.

[0165] Light-emitting auxiliary layer:

[0166] In the organic electroluminescent device of the present invention, an auxiliary light-emitting layer can be disposed between the hole transport layer and the light-emitting layer, and particularly in contact with the light-emitting layer. The auxiliary light-emitting layer is disposed in contact with the light-emitting layer, and therefore, hole transfer at the interface between the light-emitting layer and the hole transport layer can be precisely controlled. In one embodiment of the present invention, the material of the auxiliary light-emitting layer is selected from the aromatic amine organic compounds of general formula (1). The thickness of the auxiliary light-emitting layer can be 5-20 nm, preferably 8-15 nm, but the thickness is not limited to this range.

[0167] Electron transmission area:

[0168] 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, but is not limited to, a hole blocking layer, an electron transport layer and an electron injection layer.

[0169] Electron injection layer:

[0170] An electron injection layer may be disposed between the electron transport layer and the cathode. The electron injection layer material is typically preferably a material with a low work function, allowing electrons to be easily injected into the organic functional material layer. Preferably, the electron injection layer material is an N-type metal. As the electron injection layer material for the organic electroluminescent device of the present invention, electron injection layer materials known in the prior art for organic electroluminescent devices can be used, such as lithium; lithium salts, such as lithium 8-hydroxyquinoline, lithium fluoride, lithium carbonate, or lithium azide; or cesium salts, such as cesium fluoride, cesium carbonate, or cesium azide.

[0171] The thickness of the electron injection layer of the present invention can be 0.1-5 nm, preferably 0.5-3 nm and more preferably 0.8-1.5 nm, but the thickness is not limited to this range.

[0172] Electron transport layer:

[0173] An electron transport layer may be disposed above the light-emitting film layer or (if present) a hole-blocking layer. The electron transport layer material is one that readily receives electrons from the cathode and transfers these electrons to the light-emitting layer. A material with high electron mobility is preferred. As the electron transport layer of the organic electroluminescent device of the present invention, electron transport layer materials known in the art for organic electroluminescent devices can be used.

[0174] As the electron transport layer of the organic electroluminescent device of the present invention, the following compounds disclosed in the prior art can be used as electron transport layer materials for the organic electroluminescent device:

[0175]

[0176] The electron transport layer also includes other compounds commonly used in electron transport layers, such as Alq3, Liq, and preferably Liq.

[0177] The thickness of the electron transport layer of the present invention can be 10-80 nm, preferably 20-60 nm, and more preferably 25-45 nm, but the thickness is not limited to this range.

[0178] Cavity barrier

[0179] A hole blocking layer can be disposed between the light-emitting layer and the electron transport layer. The hole blocking layer prevents holes injected from the anode from passing through the light-emitting layer and entering the electron transport layer. As the hole blocking layer of the organic electroluminescent device of the present invention, the following hole blocking layer materials for organic electroluminescent devices disclosed in the prior art can be used:

[0180]

[0181] Overlay:

[0182] To improve the light extraction efficiency of organic electroluminescent devices, a CPL layer (i.e., capping layer, also known as a light extraction layer) can be added to the cathode of the device. Compounds disclosed in the art in the prior art can be used as CPL layer materials:

[0183]

[0184] The thickness of the CPL capping layer is typically 5-300 nm, preferably 20-100 nm, and more preferably 40-80 nm.

[0185] The organic electroluminescent device of the present invention may further include an encapsulation structure. The encapsulation structure may be a protective structure preventing external 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.

[0186] This invention discloses a method for fabricating organic electroluminescent devices, comprising sequentially laminating an anode, a hole injection layer, a hole transport layer, a light-emitting auxiliary layer, a light-emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, and a cathode, and optionally a capping layer, onto a substrate. In this regard, methods such as vacuum deposition, vacuum evaporation, spin coating, casting, LB method, inkjet printing, laser printing, or LITI can be used, but are not limited to these. In this 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.

[0187] In addition, it should be noted that the materials used to form each layer described in this invention can be used as a single layer by forming a film on their own, or they can be used as a single layer by mixing with other materials to form a film. They can also be a stacked structure between layers that are formed on their own, a stacked structure between layers that are formed by mixing, or a stacked structure between layers that are formed on their own and layers that are formed by mixing.

[0188] Preparation Examples

[0189] Preparation of intermediate M-1:

[0190] (1)

[0191] (2)

[0192] (3)

[0193] (1) Under a nitrogen atmosphere, 15 mmol (4.76 g) of raw material D-1 was added to a three-necked flask, and 40 ml of DMSO was added to dissolve it. The mixture was stirred under nitrogen for 1 hour, and then 5 mmol (0.97 g) of raw material C-1 and 12.5 mmol (4.07 g) of Cs2CO3 were slowly added. The mixture was heated to 130 °C and reacted for 24 hours. The reaction was observed by thin-layer chromatography (TLC) until the reaction was complete. The mixture was allowed to cool naturally, filtered, and the filtrate was rotary evaporated and passed through a silica gel column to obtain intermediate J-1.

[0194] (2) Under nitrogen protection, 50 mmol (15.14 g) of intermediate J-1, 52.5 mmol (13.33 g) of raw material B-1, 200 ml of xylene, 0.5 mmol (0.112 g) of palladium acetate, 0.5 mmol (0.238 g) of 2-dicyclohexylphosphine-2',4',6'-triisopropylbiphenyl and 60 mmol (4.92 g) of anhydrous NaOAc were added to a flask equipped with a magnetic stir bar. The resulting mixture was transferred to a preheated oil bath (110°C) and stirred for 17 hours. The reaction mixture was evacuated until all volatiles were distilled off, and the product was then distilled off and placed into a liquid nitrogen trap to obtain intermediate P-1.

[0195] (3) Under a nitrogen atmosphere, 60 mmol (16.97 g) of raw material A-1 was added to a three-necked flask and dissolved in a mixed solvent (100 ml toluene, 50 ml ethanol, 50 ml H2O). The mixture was stirred under nitrogen for 1 hour, and then 50 mmol (19.71 g) of intermediate P-1, 72 mmol (9.95 g) of K2CO3, and 2 mmol (2.31 g) of Pd(PPh3)4 were slowly added. The mixture was heated to 75 °C and reacted for 4 hours. The reaction was observed by thin-layer chromatography (TLC) until the reaction was complete. The mixture was allowed to cool naturally, filtered, and the filtrate was rotary evaporated and passed through a silica gel column to obtain intermediate M-1.

[0196] The synthetic routes for other intermediates M are similar to those for intermediate M-1, and the starting materials required for the reaction are shown in Table 1 below:

[0197] Table 1

[0198]

[0199] Preparation of intermediate R-1:

[0200]

[0201] Under a nitrogen atmosphere, 60 mmol (16.99 g) of starting material H-1 was added to a three-necked flask and dissolved in a mixed solvent (100 ml toluene, 50 ml ethanol, 50 ml H2O). The mixture was stirred under nitrogen for 1 hour. Then, 50 mmol (11.93 g) of starting material K-1, 72 mmol (9.95 g) of K2CO3, and 2 mmol (2.31 g) of Pd(PPh3)4 were slowly added. The mixture was heated to 75 °C and reacted for 5 hours. The reaction was observed by thin-layer chromatography (TLC) until complete. After natural cooling, the mixture was filtered, and the filtrate was rotary evaporated and passed through a silica gel column to obtain intermediate R-1.

[0202]

[0203] The preparation method of intermediate R-2 is similar to that of intermediate R-1, except that raw material H-1 is replaced with raw material H-2.

[0204] Preparation of intermediate N-1:

[0205]

[0206] In a three-necked flask, under nitrogen protection, add 10 mmol (2.79 g) of raw material E-1, 12 mmol (2.03 g) of raw material F-1, and 150 ml of toluene, and stir to mix. Then add 4 × 10⁻⁶ ml of toluene. -2 mmol (0.037g)Pd2(dba)3, 4×10 -20.008 g of tri-tert-butylphosphine and 25 mmol of sodium tert-butoxide were heated under reflux for 14 hours. A sample was taken and spotted onto a TLC plate, showing no remaining starting material E-1, indicating that the reaction was complete. The mixture was allowed to cool naturally to room temperature, filtered, and the filtrate was rotary evaporated until no fraction was obtained. The filtrate was then passed through a silica gel column to obtain intermediate N-1.

[0207] The following intermediate N was prepared using the same method as intermediate N-1, and the raw materials for synthesis are shown in Table 2 below;

[0208] Table 2

[0209]

[0210] Synthesis Example 1: Synthesis of Compound 66

[0211]

[0212] In a three-necked flask, under nitrogen protection, add 10 mmol (4.12 g) of intermediate N-1, 12 mmol (5.08 g) of intermediate M-2, and 150 ml of toluene, and stir to mix. Then add 5 × 10⁻⁶ ml of toluene. -2 mmol (0.046g)Pd2(dba)3, 5×10 -2 0.010 g (mmol) of tri-tert-butylphosphine and 2.88 g (mmol) of sodium tert-butoxide were added and refluxed for 12 hours. TLC sampling showed no residual intermediate N-1, indicating complete reaction. The mixture was allowed to cool naturally to room temperature, filtered, and the filtrate was rotary evaporated until no fraction remained. The filtrate was then passed through a silica gel column to give compound 66. Elemental analysis of the structure (molecular formula C6) is required. 56 H 35 NO2): Elemental analysis results: C, 89.20; H, 4.63; N, 1.89. LC-MS: Measured value: 754.39 ([M+H]). + ).

[0213] The following compounds were prepared using the same method as in Example 1, and the raw materials are shown in Table 3 below;

[0214] Table 3

[0215]

[0216]

[0217]

[0218] The following describes in detail the application effects of the aromatic amine organic compounds of the present invention in the devices through device examples 1-22 and device comparative examples 1-11. The device fabrication process of device examples 1-22 is exactly the same as that of device comparative examples 1-11, and the same substrate material and electrode material are used. The film thickness of the electrode material is also kept consistent. The only difference is that the light-emitting auxiliary layer material in the device is changed.

[0219] Device Comparison Example 1

[0220] The specific preparation process is as follows:

[0221] like Figure 1 As shown, an anode layer 2 (Ag (100nm)) is vacuum-deposited on the glass substrate layer 1. On the anode layer 2, HT1 and HI1 with a thickness of 10nm are deposited using a vacuum evaporation apparatus as a hole injection layer 3, with a mass ratio of HT1 to HI1 of 97:3. Next, a 120nm thick layer of HT1 is deposited as a hole transport layer 4. Following this, a 10nm thick layer of EB-1 is deposited as a light-emitting auxiliary layer 5. After the above light-emitting auxiliary materials are deposited, the light-emitting layer 6 of the organic electroluminescent device is fabricated. The light-emitting layer 6 uses BH1 as the host material and BD1 as the dopant material, with a doping ratio of 3% by weight. The thickness of the light-emitting layer 6 is 20nm. After the light-emitting layer 6, HB1 is deposited with a thickness of 5nm as a hole blocking layer 7. On top of the hole blocking layer 7, ET-1 and Liq are deposited with a mass ratio of ET-1 to Liq of 1:1. The vacuum-deposited film of this material has a thickness of 30nm, and this layer is the electron transport layer 8. On electron transport layer 8, a 1 nm thick LiF layer is fabricated using a vacuum evaporation apparatus; this layer serves as electron injection layer 9. On electron injection layer 9, a 16 nm thick Mg:Ag electrode layer is fabricated using a vacuum evaporation apparatus, with a Mg to Ag mass ratio of 1:9; this layer serves as cathode layer 10. On cathode layer 10, a 65 nm thick CP-1 layer is vacuum-evaporated as CPL layer 11.

[0222] The preparation methods of devices 1-22 are the same as those of device comparative example 1, except that the organic material of the light-emitting auxiliary layer 5 uses the aromatic amine organic compound of the present invention. The preparation methods of devices comparative examples 2-11 are the same as those of device comparative example 1, except that the organic material of the light-emitting auxiliary layer 5 uses the comparative compounds EB-2, EB-3, EB-4, EB-5, EB-6, EB-7, EB-8, EB-9, EB-10, and EB-11. The specific structures of devices 1-22 and devices comparative examples 1-11 are detailed in Table 4.

[0223] The molecular structural formulas of the relevant materials are shown below:

[0224] HT1

[0225] ET1 HB1

[0226] EB-1 EB-2 EB-3

[0227] EB-4 EB-5 EB-6

[0228] EB-7 EB-8 EB-9

[0229] EB-10 EB-11.

[0230] Table 4

[0231]

[0232]

[0233]

[0234] In Table 4 above, taking Example 1 as an example, "HI1:HT1=3:97 10nm" in the second column indicates that the material used for the hole injection layer is compound HT1 and P-type doped material HI1, 3:97 refers to the weight ratio of P-type doped material HI1 to compound HT1 is 3:97, and 10nm indicates the thickness of the layer; "66 10nm" in the fourth column indicates that the material used is compound 66, and the thickness of the layer is 10nm, and so on, the meanings in other tables.

[0235] After fabricating the organic electroluminescent device as described above, the cathode and anode were connected using a known driving circuit, and various performance parameters of the device were measured. The performance measurement results of the devices in Examples 1-22 and Comparative Examples 1-11 are shown in Table 5.

[0236] Table 5

[0237]

[0238] Note: Current efficiency and color coordinates were measured using an IVL (current-voltage-luminance) testing system (Suzhou Fushida Scientific Instruments Co., Ltd.), with a current density of 10 mA / cm² during testing. 2 The lifetime testing system is the EAS-62C OLED device lifetime tester from System Technology Inc., Japan; LT95 refers to a current density of 30 mA / cm². 2 Under certain conditions, the time it takes for the device's brightness to decay to 95% of its original brightness.

[0239] As can be seen from the device data results in Table 5, compared with the device comparative examples 1-11, the organic electroluminescent device of the present invention, which uses aromatic amine organic compounds as the light-emitting auxiliary layer, achieves a significant improvement in both efficiency and lifetime compared with organic electroluminescent devices made of known materials.

[0240] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are exhaustively listed. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0241] For those skilled in the art, various modifications and improvements can be made without departing from the concept of the present invention, and these modifications and improvements are all within the scope of protection of the present invention. The scope of protection of the present invention is defined by the appended claims.

Claims

1. An aromatic amine organic compound, characterized in that, The structure of the aromatic amine organic compounds is shown in general formula (1): General formula (1) In general formula (1), Ar1 and Ar2 represent C6-C atoms substituted or unsubstituted, respectively. 30 aryl or C2-C 30 heteroaryl groups; L1 and L2 represent a single bond, a phenylene group substituted or unsubstituted with a substituent, a naphthylene group substituted or unsubstituted with a substituent, and a diphenylene group substituted or unsubstituted with a substituent, respectively. The substituent is selected from one or more of the following: deuterium atom, methyl, ethyl, tert-butyl, phenyl, naphthyl, and diphenyl. Any hydrogen atom in general formula (1) can be replaced by a deuterium atom.

2. The aromatic amine organic compound according to claim 1, characterized in that, The structures of the aromatic amine organic compounds are shown in any one of general formulas (1-1) to (1-12): General formula (1-1) General formula (1-2) General formula (1-3) General formula (1-4) General formula (1-5) General formula (1-6) General formula (1-7) General formula (1-8) General formula (1-9) General formula (1-10) General formula (1-11) General formula (1-12) In formulas (1-1) to (1-12), the meanings of L2 and Ar2 are the same as those defined in formula (1) of claim 1.

3. The aromatic amine organic compound according to claim 1, characterized in that, The structures of the aromatic amine organic compounds are shown in any one of general formulas (2-1) to (2-12): General formula (2-1) General formula (2-2) General formula (2-3) General formula (2-4) General formula (2-5) General formula (2-6) General formula (2-7) General formula (2-8) General formula (2-9) General formula (2-10) General formula (2-11) General formula (2-12) In formulas (2-1) to (2-12), the meanings of L2 and Ar2 are the same as those defined in formula (1) of claim 1.

4. The aromatic amine organic compound according to claim 1, characterized in that, The structures of the aromatic amine organic compounds are shown in any one of general formulas (3-1) to (3-10): General formula (3-1) General formula (3-2) General formula (3-3) General formula (3-4) General formula (3-5) General formula (3-6) General formula (3-7) General formula (3-8) General formula (3-9) General formula (3-10) In general formulas (3-1) to (3-10), X is an oxygen atom or a sulfur atom, and the meanings of L2 and Ar2 are the same as those defined in general formula (1) of claim 1.

5. The aromatic amine organic compound according to claim 1, characterized in that, The structures of the aromatic amine organic compounds are shown in any one of general formulas (4-1) to (4-8): General formula (4-1) General formula (4-2) General formula (4-3) General formula (4-4) General formula (4-5) General formula (4-6) General formula (4-7) General formula (4-8) In formulas (4-1) to (4-8), L2 and Ar2 have the same meanings as defined in formula (1) of claim 1.

6. The aromatic amine organic compound according to claim 1, characterized in that, The structures of the aromatic amine organic compounds are shown in any one of general formulas (5-1) to (5-4): General formula (5-1) General formula (5-2) General formula (5-3) General formula (5-4).

7. The aromatic amine organic compound according to any one of claims 1-6, characterized in that, Ar1 and Ar2 respectively represent phenyl (substituted or unsubstituted), naphthyl (substituted or unsubstituted), diphenyl (substituted or unsubstituted), dibenzofuranyl (substituted or unsubstituted), dibenzothiophene (substituted or unsubstituted), naphthobenzofuranyl (substituted or unsubstituted), naphthobenzothiophene (substituted or unsubstituted), phenanthrene (substituted or unsubstituted), triphenylene (substituted or unsubstituted), and furanyl (substituted or unsubstituted). The following are substituents: thiophene group (substituted or unsubstituted), indol group (substituted or unsubstituted), carbazolyl group (substituted or unsubstituted), benzocarbazolyl group (substituted or unsubstituted), fluorenyl group (substituted or unsubstituted), dimethylfluorenyl group (substituted or unsubstituted), diphenylfluorenyl group (substituted or unsubstituted), spirofluorenyl group (substituted or unsubstituted), silanylfluorenyl group (substituted or unsubstituted), and spirosiliconylfluorenyl group (substituted or unsubstituted), wherein the substituents are substituted by single bond substitution or cyclic substitution. L1 and L2 respectively represent a single bond, a phenylene group substituted or unsubstituted with a substituent, a naphthylene group substituted or unsubstituted with a substituent, and a diphenylene group substituted or unsubstituted with a substituent; The substituent is selected from one or more of the following: deuterium atom, methyl, ethyl, tert-butyl, phenyl, naphthyl, and diphenyl. Preferably, L1 and L2 represent single bonds or the following structures: , , , , , , , , , , Any one of them; Ar1 and Ar2 are each independently represented by the following structures: 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 , , , , , , , , , , , , , , , , , , , Any one of them; * indicates a connection site.

8. An aromatic amine organic compound according to claim 1, characterized in that, The structure of the aromatic amine organic compound is selected from any one of the following structural formulas: (1) (2) (3) (4) (5) (6) (7) (8) (9) (10) (11) (12) (13) (14) (15) (16) (17) (18) (19) (20) (21) (22) (23) (24) (25) (26) (27) (28) (29) (30) (31) (32) (33) (34) (35) (36) (37) (38) (39) (40) (41) (42) (43) (44) (45) (46) (47) (48) (49) (50) (51) (52) (53) (54) (55) (56) (57) (58) (59) (60) (61) (62) (63) (64) (65) (66) (67) (68) (69) (70) (71) (72) (73) (74) (75) (76) (77) (78) (79) (80) (81) (82) (83) (84) (85) (86) (87) (88) (89) (90) (91) (92) (93) (94) (95) (96) (97) (98) (99) (100) (101) (102) (103) (104) (105) (106) (107) (108) (109) (110) (111) (112) (113) (114) (115) (116) (117) (118) (119) (120) (121) (122) (123) (124) (125) (126) (127) (128) (129) (130) (131) (132) (133) (134) (135) (136) (137) (138) (139) (140) (141) (142) (143) (144) (145) (146) (147) (148) (149) (150) (151) (152) (153) (154) (155) (156) (157) (158) (159) (160) (161) (162) (163) (164) (165) (166) (167) (168) (169) (170) (171) (172) (173) (174) (175) (176) (177) (178) (179) (180) (181) (182) (183) (184) (185) (186) (187) (188) (189) (190) (191) (192) (193) (194) (195) (196) (197) (198) (199) (200) (201) (202) (203) (204) (205) (206) (207) (208) (209) (210)。 9. An organic electroluminescent device, comprising, in sequence, a substrate, a first electrode, an organic functional layer, and a second electrode, characterized in that, The organic functional layer contains an aromatic amine organic compound as described in any one of claims 1-8; Preferably, the organic functional layer includes a hole transport region, a light-emitting region, and an electron transport region, wherein the hole transport region contains an aromatic amine organic compound as described in any one of claims 1-8.

10. The organic electroluminescent device according to claim 9, wherein the hole transport region comprises a hole injection layer, a hole transport layer and a light-emitting auxiliary layer, and the light-emitting auxiliary layer contains an aromatic amine organic compound according to any one of claims 1-8.

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