Organic electroluminescent compound, organic electroluminescent material containing double hosts and organic electroluminescent device

Abstract

The invention provides an organic electroluminescent compound, an organic electroluminescent material containing double hosts and an organic electroluminescent device.The organic electroluminescent compound is of a structure shown in the general formula (1). A first host compound with a specific structure and a second host compound with a specific structure are compounded; wherein the first host material adopts a molecule taking triarylamine as a skeleton, the molecule has relatively high glass transition temperature and molecular thermal stability, proper HOMO and LUMO energy levels and relatively high Eg, and meanwhile, the second host with a triazine structure is matched, so that hole transport and electron transport capabilities can be enhanced at the same time; therefore, when holes are injected into the p-type main body and electrons are injected into the n-type main body, the driving voltage is reduced, and the service life is prolonged.

Description

Technical Field

[0001] The present invention belongs to the field of organic electroluminescent materials, and in particular relates to an organic electroluminescent compound, an organic electroluminescent material containing a double host, and an organic electroluminescent device. Background Art

[0002] Organic electroluminescent devices are self-luminous devices that have attracted widespread attention in the panel display device industry due to their low driving voltage, high resolution, high brightness, fast response time, and flexibility. In addition, the raw materials have low production costs, are easy to process, and have high purity.

[0003] Currently, OLED display technology has been applied in fields such as smartphones and tablets, and will also expand to large-size application fields such as TVs. However, compared with actual product application requirements, OLED's luminous efficiency and service life and other performance still need to be further improved.

[0004] The luminescent material of an organic electroluminescent device (OLED) is the most important factor in determining the device's luminous efficiency. Functionally, it can be divided into a host material and a dopant material. By mixing a host and a dopant, the luminescent material can be used to improve color purity, luminous efficiency, and stability. Devices with excellent electroluminescent (EL) properties typically have a structure in which a luminescent layer is formed by doping a host with a dopant. When using such a dopant / host material system as the luminescent material, the host material significantly affects the efficiency and lifespan of the luminescent device, making the selection of a suitable host material crucial.

[0005] Therefore, the current urgent task is to develop OLEDs with high efficiency and long life characteristics, especially considering the EL characteristics required for medium and large OLED panels, it is urgent to develop light-emitting materials that are superior to conventional light-emitting materials and have excellent performance. Summary of the Invention

[0006] In view of the deficiencies of the prior art, the object of the present invention is to provide an organic electroluminescent compound, an organic electroluminescent material containing a dual host, and an organic electroluminescent device.

[0007] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0008] In one aspect, the present invention provides an organic electroluminescent compound having a structure represented by general formula (1):

[0009]

[0010] Wherein, R1 and R2 are each independently selected from substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C6-C30 heteroaryl; the heteroatom in the heteroaryl is selected from O, N or S;

[0011] X represents O or S;

[0012] Ar1 and Ar2 are each independently selected from substituted or unsubstituted C6-C 30 Aryl, substituted or unsubstituted C6-C 30 Heteroaryl, substituted or unsubstituted C 10 -C 30 wherein the heteroaryl group includes a monocyclic aromatic group or a polycyclic aromatic group containing at least one heteroatom, wherein the heteroatom includes but is not limited to O, S, and N; and Ar1 or Ar2 contains at least one group selected from the following groups:

[0013]

[0014] All hydrogen atoms in the general formula (1) may be completely unsubstituted by deuterium, completely substituted by deuterium, or partially substituted by deuterium.

[0015] According to one embodiment of the present invention, Ar1 is selected from the following groups, and the following groups may be further substituted by deuterium:

[0016]

[0017] Ar2 is selected from the following groups, and the following groups may be further substituted with deuterium:

[0018]

[0019] According to one embodiment of the present invention, R1 and R2 are selected from the following groups, which can be connected at any substitutable site, and the following groups can be further substituted with deuterium:

[0020]

[0021] Where D represents deuterium, Indicates the attachment position of the group.

[0022] According to one embodiment of the present invention, the structural compound represented by the general formula (1) is selected from any one of H1-1 to H1-260:

[0023]

[0024]

[0025]

[0026]

[0027]

[0028]

[0029]

[0030]

[0031]

[0032]

[0033]

[0034]

[0035]

[0036] The above are some specific structural forms of organic electroluminescent compounds, but are not limited to these chemical structures listed. All compounds with simple changes of groups within the defined range based on the general structural formula shown in formula (1) should be included.

[0037] On the other hand, the present invention also provides an organic electroluminescent material containing dual host materials, wherein the organic electroluminescent material comprises a first host material and a second host material, wherein the first host material has a compound having a structure represented by the above general formula (1); and the second host material has a compound having a structure represented by the general formula (2):

[0038]

[0039] wherein L1 to L3 are each independently selected from a connecting bond, a substituted or unsubstituted C6-C 30 Aryl, substituted or unsubstituted C6-C 30 heteroaryl;

[0040] D1 to D3 are each independently selected from substituted or unsubstituted C6-C 30 Aryl, substituted or unsubstituted C6-C 30 Heteroaryl, substituted or unsubstituted C 10 -C 30 wherein the heteroaryl group is a monocyclic aromatic group or a polycyclic aromatic group including at least one heteroatom, and the heteroatom includes but is not limited to O, S, N, P, and Si.

[0041] Further, D1 is selected from C6-C36 Aryl, substituted or unsubstituted C6-C 30 Heteroaryl: A heteroaryl is a monocyclic aromatic group or a polycyclic aromatic group that includes at least one heteroatom, and the heteroatom includes but is not limited to O, S, N, P, and Si.

[0042] According to one embodiment of the present invention, the D1 is selected from the following groups, which can be connected at any substitutable site, and the following groups can be further substituted with deuterium:

[0043]

[0044] Preferably, D2 and D3 are each independently selected from the following substituted or unsubstituted groups:

[0045]

[0046] Preferably, L2 and L3 are each independently selected from a linker, a phenyl group, or a naphthyl group;

[0047] Preferably, L1 is selected from a linker, an unsubstituted (C6-C 18 )aryl, substituted or unsubstituted (C6-C 18 ) heteroaryl, wherein the heteroatom is selected from O, S, N, P, Si.

[0048] The "substituted" is selected from deuterium, cyano, methyl, (C6-C 24 )aryl, (C6-C 24 ) heteroaryl, wherein the heteroatom is selected from O, S, N, P, Si.

[0049] In the present invention, the second host material has any one of the following structures, but is not limited thereto:

[0050]

[0051]

[0052]

[0053]

[0054]

[0055]

[0056]

[0057]

[0058]

[0059]

[0060]

[0061]

[0062] The above is the specific structural formula of the second main material. The present invention prefers the above structure but is not limited to it. All compounds based on the structure shown in general formula (2) and in which L1 to L3 and D1 to D3 groups are simple transformations of groups within all the previously defined ranges should be included.

[0063] The present invention also provides a method for preparing an organic electroluminescent material containing two hosts, which specifically includes a method for preparing the first host material and the second host material, and the specific steps are as follows:

[0064] 1. The synthesis method of the first host material of formula 1 is as follows:

[0065] (1) Reactant 1 (1 eq), reactant 2 (1 eq), and potassium carbonate (2 eq) were added to a reactor and replaced with nitrogen three times. A mixture of water and tetrahydrofuran was added as a solvent and replaced with nitrogen three times. Pd(Ph3)4 (0.01 eq) was then added and replaced with nitrogen three times. The mixture was heated to 80°C under nitrogen protection and reacted for 12 hours. After the reaction was completed, the mixture was cooled to room temperature, and then the solvent was removed under reduced pressure. The crude product was purified by column chromatography to obtain intermediate 1-1.

[0066] (2) The intermediate 1-1 (1 eq), pinacol diboron (1.5 eq), and potassium acetate (2 eq) were added to the reactor and replaced with nitrogen three times. 1,4-dioxane was added as a solvent and replaced with nitrogen three times. Pd2(dba)3 (0.01 eq) and X-phos (0.08 eq) were added and replaced with nitrogen three times. The temperature was raised to 100°C under nitrogen protection and the reaction was carried out for 12 hours. After the reaction was completed, the mixture was cooled to room temperature, and then the solvent was removed under reduced pressure. The crude product was purified by column chromatography to obtain the intermediate 1-2.

[0067] (3) Intermediate 1-2 (1 eq), reactant 3 (1 eq), and potassium carbonate (2 eq) were added to a reactor and replaced with nitrogen three times. A mixture of water and tetrahydrofuran was added as a solvent and replaced with nitrogen three times. Pd(Ph3)4 (0.01 eq) was then added and replaced with nitrogen three times. The mixture was heated to 80°C under nitrogen protection and reacted for 12 hours. After the reaction was completed, the mixture was cooled to room temperature, and then the solvent was removed under reduced pressure. The crude product was purified by column chromatography to obtain intermediate 1-3.

[0068] (4) The intermediate 1-3 (1 eq), the reactant 4 (1 eq), and sodium tert-butoxide (2 eq) were sequentially added to a reaction vessel, and toluene was added thereto as a reaction solvent. Catalysts Pd2(dba)3 (0.01 eq) and P(t-Bu)3 (0.02 eq) were added thereto under nitrogen protection. The mixture was refluxed at 120°C for 24 hours under nitrogen protection, and then cooled to 25°C. Purified water was added thereto, and the mixture was stirred for 30 minutes, allowed to stand for stratification, separated, and subjected to column chromatography to obtain the final product of the general formula 1.

[0069]

[0070] 2. Synthesis of the second host material

[0071] (1) Reactant (1 eq), reactant 2 (1 eq), and potassium carbonate (2 eq) were weighed and added to a reaction vessel in sequence. Tetrahydrofuran and water were then added as reaction solvents. Catalyst Pd(PPh3)4 (0.02 eq) was added under nitrogen protection. The mixture was refluxed at 80°C for 24 hours under nitrogen protection, then cooled to 25°C, purified water was added, stirred for 30 minutes, allowed to stand, separated, and subjected to column chromatography to obtain intermediate 2-1.

[0072] (2) The intermediate 2-1 (1 eq), the reactant 3 (1 eq), and potassium carbonate (2 eq) were weighed and added to a reaction vessel in sequence, and tetrahydrofuran and water were added thereto as reaction solvents. The catalyst Pd(PPh3)4 (0.02 eq) was added thereto under nitrogen protection, and the mixture was refluxed at 80°C for 24 hours under nitrogen protection, and then cooled to 25°C. Purified water was added thereto, and the mixture was stirred for 30 minutes, allowed to stand for stratification, separated, and subjected to column chromatography to obtain the final product of general formula 2.

[0073]

[0074] The present invention also provides an organic electroluminescent device, which comprises the organic electroluminescent material containing dual hosts.

[0075] In one embodiment of the present invention, the organic electroluminescent device includes a first electrode, a hole injection layer, a hole transport layer, a light-emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer and a second electrode arranged in sequence; the material of the light-emitting layer includes the organic electroluminescent material containing a dual host and also includes a doping material.

[0076] Moreover, in one embodiment of the present invention, the mass ratio of the organic electroluminescent material containing a dual host to the doping material in the light-emitting layer is (5-199):1, for example, 5:1, 10:1, 15:1, 20:1, 30:1, 35:1, 40:1, 45:1, 50:1, 60:1, 70:1, 80:1, 90:1, 100:1, 120:1, 140:1, 160:1, 180:1 or 199:1, preferably (5-100):1, and more preferably (5-15):1.

[0077] In one embodiment of the present invention, the preparation method of the light-emitting layer includes but is not limited to forming the light-emitting layer from the organic electroluminescent material by solution coating and vacuum deposition; herein, solution coating refers to spin coating, dip coating, inkjet printing, screen printing, spraying, etc., but is not limited thereto.

[0078] In one embodiment of the present invention, the first electrode is an anode.

[0079] Anode materials typically have a high work function to facilitate hole injection into the organic layer. Anode materials that can be used in the present invention include, but are not limited to, metals such as vanadium, chromium, copper, zinc, or their alloys; metal oxides such as zinc oxide, indium oxide, indium tin oxide (ITO), or indium zinc oxide (IZO); combinations of metals and oxides such as ZnO / Al or SnO2 / Sb; and conductive polymers such as poly(3-methylthiophene), polypyrrole, or polyaniline. In certain embodiments of the present invention, the anode is an ITO anode.

[0080] In one embodiment of the present invention, the material of the hole injection layer is selected from one or more of metalloporphyrins, oligothiophenes, arylamine-based organic materials, benzonitrile-based organic materials, quinacridone-based organic materials, polyaniline-based and polythiophene-based conductive polymers.

[0081] The hole injection layer is a material that receives holes from the anode at a low voltage, and the highest occupied molecular orbital (HOMO) of the hole injection layer is preferably between the work function of the anode material and the HOMO of the surrounding organic material layer.

[0082] In one embodiment of the present invention, the material of the hole transport layer is selected from one or more of an organic material based on arylamine, a conductive polymer, and a block copolymer having both conjugated and non-conjugated portions. The material of the hole transport layer is capable of receiving holes from the anode or the hole injection layer and transporting the holes to the light-emitting layer, and has high hole mobility.

[0083] In one embodiment of the present invention, the electron transport layer is selected from one or more of an Al complex of 8-hydroxyquinoline and an organic free radical compound, but is not limited thereto.

[0084] In one embodiment of the present invention, the thickness of the electron transport layer is 1 nm to 50 nm, for example, 1 nm, 2 nm, 4 nm, 6 nm, 8 nm, 10 nm, 15 nm, 20 nm, 25 nm, 30 nm, 35 nm, 40 nm, 45 nm, or 50 nm.

[0085] The electron transport layer prevents a decrease in electron transport properties and an increase in driving voltage caused by an excessively thick electron transport layer, thereby promoting electron transport. The material of the electron transport layer receives electrons from the cathode and transfers them to the light-emitting layer, exhibiting high electron mobility.

[0086] In one embodiment of the present invention, the electron injection layer is selected from one or more of fluorenone, anthraquinone dimethane, diphenoquinone, thiopyran dioxide, imidazole, perylene tetracarboxylic acid, fluorenylene methane, anthrone or its derivatives, metal complexes, and nitrogen-containing five-membered ring derivatives, but is not limited thereto.

[0087] The electron injection layer can promote electron injection, and the electron injection material preferably has the ability to transport electrons, has an electron injection effect from the cathode, has an excellent electron injection effect on the light-emitting layer or the light-emitting material, prevents the excitons generated in the light-emitting layer from migrating to the hole injection layer, and in addition has excellent thin film forming ability.

[0088] In one embodiment of the present invention, the second electrode is a cathode.

[0089] To facilitate electron injection into the organic layer, cathode materials are typically preferably those with a low work function. Specific examples of cathode materials include, but are not limited to, metals such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin, and lead, or their alloys; and multilayered structures such as LiF / Al or LiO2 / Al. In certain embodiments of the present invention, the cathode material is Al.

[0090] In one embodiment of the present invention, the organic electroluminescent device may be a top emission type, a bottom emission type, or a double-side emission type.

[0091] The numerical range described in the present invention includes not only the point values ​​listed above, but also any point values ​​between the above numerical ranges that are not listed. Due to space limitations and for the sake of simplicity, the present invention no longer exhaustively lists the specific point values ​​included in the range.

[0092] Compared with the prior art, the present invention has the following beneficial effects:

[0093] The present invention provides an organic electroluminescent material having two host materials, wherein the organic electroluminescent material comprises a first host material and a second host material, wherein the first host material is a compound having a structure represented by general formula (1), and the second host material is a compound having a structure represented by general formula (2). By using a specific combination of compounds as host materials in an organic electroluminescent device, the luminous efficiency and service life of the device can be effectively improved.

[0094] Specifically, the present invention adopts a compound of a first host compound with a specific structure and a second host compound with a specific structure, wherein the first host material adopts a molecule with a triarylamine skeleton, which has a high glass transition temperature and molecular thermal stability, suitable HOMO and LUMO energy levels, and a high Eg. At the same time, it is matched with a second host with a triazine structure, which has the ability to simultaneously enhance hole transport and electron transport. Therefore, when holes are injected into the p-type host and electrons are injected into the n-type host, the driving voltage is reduced while the lifespan is also enhanced. BRIEF DESCRIPTION OF THE DRAWINGS

[0095] Figure 1 This is the hydrogen nuclear magnetic resonance spectrum of compound H1-6 provided in the examples of the present invention. DETAILED DESCRIPTION

[0096] The technical solution of the present invention is further described below by way of specific embodiments. It should be understood by those skilled in the art that the embodiments are merely to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0097] It should be noted that the numerical values ​​given in the following examples are as accurate as possible, but those skilled in the art understand that due to unavoidable measurement errors and experimental operation problems, each number should be understood as an approximate number rather than an absolutely accurate value.

[0098] The features and performance of the present invention will be further described in detail below with reference to the embodiments.

[0099] Example 1: Preparation of the first host compound H1-6

[0100] (1) 2-Bromo-7-chlorobenzo[d]oxazole (1 eq), 2-(dibenzo[b,d]furan-1-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane (1 eq), and potassium carbonate (2 eq) were added to a reactor and replaced with nitrogen three times. A mixture of water and tetrahydrofuran was added as a solvent and replaced with nitrogen three times. Pd(PPh3)4 (0.02 eq) was then added and replaced with nitrogen three times. The mixture was heated to 80°C under nitrogen protection and reacted for 12 hours. After the reaction was completed, the mixture was cooled to room temperature, and then the solvent was removed under reduced pressure. The crude product was purified by column chromatography to obtain intermediate H1-6-a (yield: 71%).

[0101] (2) The intermediate H1-6-a (1 eq), N,N-diphenyl-2-(4,4,5,5-tetramethyl-1,3,2-dioxaborol-2-yl)aniline (1 eq), and potassium carbonate (2 eq) were added to a reactor and replaced with nitrogen three times. A mixture of water and tetrahydrofuran was added as a solvent and replaced with nitrogen three times. Pd(PPh3)4 (0.02 eq) was then added and replaced with nitrogen three times. The mixture was heated to 80°C under nitrogen protection and reacted for 12 hours. After the reaction was completed, the mixture was cooled to room temperature, and then the solvent was removed under reduced pressure. The crude product was purified by column chromatography to obtain the final product H1-6 (yield: 62%, HPLC>99%, mass spectrometry test value: 528.83).

[0102]

[0103] Example 2: Preparation of the first host compound H1-67

[0104] (1) 4-Bromo-2-(phenyl-D5)benzo[D]oxazole (1 eq), pinacol diboron (1.5 eq), and potassium acetate (2 eq) were added to a reactor and replaced with nitrogen three times. 1,4-dioxane was added as a solvent and replaced with nitrogen three times. Pd2(dba)3 (0.01 eq) and X-phos (2-dicyclohexylphosphine-2',4',6'-triisopropylbiphenyl, 0.08 eq) were added and replaced with nitrogen three times. The mixture was heated to 100°C under nitrogen protection and reacted for 12 hours. After the reaction was completed, the mixture was cooled to room temperature, and then the solvent was removed under reduced pressure. The crude product was purified by column chromatography to obtain intermediate H1-67-a (yield 75%).

[0105] (2) The intermediate H1-67-a (1 eq), 3-bromo-7-chloro-1-phenyldibenzo[b,d]furan (1 eq), and potassium carbonate (2 eq) were added to a reactor and replaced with nitrogen three times. A mixture of water and tetrahydrofuran was added as a solvent and replaced with nitrogen three times. Pd(PPh3)4 (0.02 eq) was then added and replaced with nitrogen three times. The mixture was heated to 80°C under nitrogen protection and reacted for 12 hours. After the reaction was completed, the mixture was cooled to room temperature, and then the solvent was removed under reduced pressure. The crude product was purified by column chromatography to obtain the intermediate H1-67-b (yield: 68%).

[0106] (3) The intermediate H1-67-b (1 eq), diphenylamine (1 eq), and sodium tert-butoxide (2 eq) were placed in a reaction flask, toluene was added, and catalysts Pd2(dba)3 (0.01 eq) and P(t-Bu)3 (0.02 eq) were added under nitrogen protection. The mixture was refluxed at 120°C for 24 hours under nitrogen protection, then cooled to 25°C, purified water was added, stirred for 30 minutes, and then allowed to stand for stratification. The mixture was separated and subjected to column chromatography to obtain the product H1-67 (yield 71%, HPLC>99%, mass spectrometry value 609.98)

[0107]

[0108] Example 3: Preparation of the first host compound H2-1

[0109] (1) B-1- Boric acid (1 eq), 2-chloro-4-(dibenzo[b,d]furan-1-yl)-6-phenyl-1,3,5-triazine (1 eq) and potassium carbonate (2 eq) were added to a reactor and the nitrogen atmosphere was replaced three times. A mixture of water and tetrahydrofuran was added as a solvent and the nitrogen atmosphere was replaced three times. Pd(PPh3)4 (0.01 eq) was then added and the nitrogen atmosphere was replaced three times. The temperature was raised to 80°C under nitrogen protection and the reaction was carried out for 12 hours. After the reaction was completed, the mixture was cooled to room temperature, and then the solvent was removed under reduced pressure. The crude product was purified by column chromatography to obtain the final product H2-1 (yield: 68%, HPLC>99%, mass spectrometry test value: 549.85).

[0110]

[0111] Example 4: Preparation of the first host compound H2-230

[0112] (4-(Dibenzo[b,d]furan-1-yl)naphthalene-1-yl)boric acid (1 eq), 2-([1,1'-biphenyl]-2-yl)-4-chloro-6-(dibenzo[b,d]furan-3-yl)-1,3,5-triazine (1 eq), and potassium carbonate (2 eq) were added to a reactor and replaced with nitrogen three times. A mixture of water and tetrahydrofuran was added as a solvent and replaced with nitrogen three times. Pd(PPh3)4 (0.01 eq) was added and replaced with nitrogen three times. The temperature was raised to 80°C under nitrogen protection and the reaction was reacted for 12 hours. After the reaction was completed, the mixture was cooled to room temperature, and then the solvent was removed under reduced pressure. The crude product was purified by column chromatography to obtain the final product H2-230 (yield 65%, HPLC>99%, mass spectrometry test value 691.92).

[0113]

[0114] Preparation of organic electroluminescent devices

[0115] The preparation method of the organic electroluminescent device is as follows:

[0116] (1) A 1500 angstrom thick ITO (indium tin oxide) glass substrate was cleaned twice in distilled water, ultrasonically cleaned for 30 minutes, and then repeatedly cleaned twice in distilled water, ultrasonically cleaned for 10 minutes. After washing, it was ultrasonically cleaned in methanol, acetone, and isopropyl alcohol (5 minutes each time), dried, and then transferred to a plasma cleaner for washing for 5 minutes to obtain an ITO anode.

[0117] (2) In an evaporation machine, HIL is vacuum-evaporated on the surface of the ITO anode obtained in step (1) to a thickness of 700 angstroms to obtain a hole injection layer.

[0118] (3) HTL is vacuum evaporated on the surface of the hole injection layer obtained in step (2), and the thickness of HTL1 and HTL2 is 50 angstroms to reach 700 angstroms to form a hole transport layer.

[0119] (4) Evaporating a light-emitting layer material on the surface of the hole transport layer using a multi-source co-evaporation method for linear gradient co-evaporation to a thickness of 300 angstroms to obtain a light-emitting layer. The light-emitting layer material includes a dual host material and a dopant material. The mass ratio of the first host compound to the second host compound in the dual host material is 60:40, and the mass ratio of the dual host material to the dopant material is 10:1. The dual host materials are the host materials provided in device Examples 1-28, Comparative Examples 1-7, and Parallel Comparative Examples 1-10.

[0120] (5) HBL is evaporated on the surface of the light-emitting layer obtained in step (4) to a thickness of 100 angstroms to form a hole blocking layer.

[0121] (6) Vacuum-evaporating an ETL with a thickness of 300 angstroms on the surface of the hole blocking layer obtained in step (5) to obtain an electron transport layer.

[0122] (7) Vacuum-evaporating Liq on the surface of the electron transport layer obtained in step (6) to a thickness of 15 angstroms to obtain an electron injection layer.

[0123] (8) 1200 angstroms of Al is evaporated on the surface of the electron injection layer obtained in step (7) to form a cathode, thereby obtaining the organic electroluminescent device.

[0124] Materials used in each functional layer of the device:

[0125]

[0126] Device Examples 1-46, Comparative Examples 1-13, Parallel Comparative Examples 1-12:

[0127] Device embodiments 1 to 46 use the dual-host material of the present invention, and the combination of the dual-host material is shown in Table 2. Among them, for the scheme in which the dual-host material includes a compound of the first host material and a compound of the second host material, the mass ratio of the compound of the first host material and the compound of the second host material is 60:40.

[0128] Comparative Examples 1 to 13 use a compound having the structure shown in Table 1, or having the general formula (1) or (2) as a single host material.

[0129] In parallel comparative examples 1-12, a host material compound having a structure represented by general formula (2) of the present invention and a compound having a structure represented by Table 1 were respectively used for mutual matching.

[0130] In Table 2, “-” indicates that the host material does not contain the compound; the structure of E is shown below. Comparative examples are shown in Table 1 below.

[0131] Table 1

[0132]

[0133]

[0134] The driving voltage, luminous efficiency, and the time taken for the brightness to decrease from 100% to 95% (lifespan; T95) of the organic electroluminescent device at a brightness of 15,000 nits were tested. The test results are shown in Table 2.

[0135] Table 2

[0136]

[0137]

[0138]

[0139]

[0140] It can be seen from device examples 1-36 that when the main material of the light-emitting layer is compounded with the compound of the first main material and the compound of the second main material of the present invention, the application in the device can greatly improve the luminous efficiency and service life.

[0141] From the performance comparison of the devices prepared in device examples 1-46 and parallel comparative examples 1-12, it can be seen that the efficiency of the organic electroluminescent device prepared in parallel comparative example 1-12 is 34.5-36.3 cd / A, the driving voltage is 3.41-3.55 V, and the lifespan is 471-478 h; while the organic electroluminescent device prepared in device example 1-46 of the present invention using a dual host material has a luminous efficiency of 43.4-46.9 cd / A, which is significantly higher than the luminous efficiency of the device in parallel comparative example 1-12; the driving voltage of device example 1-46 of the present invention is 3.12-3.27 V, which is significantly lower than the driving voltage of the device in parallel comparative example 1-12; the lifespan of the device in device example 1-46 of the present invention is 605-638 h, which is much higher than the service life of the device in parallel comparative example 1-12.

[0142] The organic compound structure of the present invention contains benzoxazole or thiazole connected to other dibenzo pentacyclic rings as a parent core structure, and the parent core is connected to an aromatic amine group, and the resulting compound can be used as a hole transport type first host material. The benzoxazole or thiazole compound in the parent core structure inherently has a high electronegativity and an electron-rich group, so that the compound disclosed herein promotes intermolecular charge transition, and at the same time connects other dibenzo pentacyclic rings, which is conducive to enhancing intermolecular stacking and more easily achieving horizontal molecular orientation, thereby enabling the realization of fast electronic current characteristics. In addition, the parent core has a larger conjugated system, and after connecting it to aromatic amine, it can enhance the intermolecular force and improve the compound carrier mobility. When the organic compound of the present invention is used as a hole transport type host material in a hybrid host material, the carrier balance in the organic light-emitting layer can be improved, the carrier recombination region can be widened, the exciton generation and utilization efficiency can be improved, and the device luminous efficiency and life can be improved.

[0143] While the present invention uses the above-described embodiments to illustrate the organic electroluminescent compounds, dual-host-containing organic electroluminescent materials, and organic electroluminescent devices of the present invention, the present invention is not limited to these embodiments, nor does it necessarily rely on these embodiments for implementation. Those skilled in the art will appreciate that any improvements to the present invention, equivalent substitutions for the raw materials used, additions of auxiliary components, and selection of specific methods, etc., fall within the scope of protection and disclosure of the present invention.

Claims

1. An organic electroluminescent compound, characterized in that The organic electroluminescent compound has a structure shown in general formula (1): Wherein, R1 and R2 are each independently selected from substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C6-C30 heteroaryl; the heteroatom in the heteroaryl is selected from O, N or S; X represents O or S; Ar1 and Ar2 are each independently selected from substituted or unsubstituted C6-C 30 Aryl, substituted or unsubstituted C6-C 30 Heteroaryl, substituted or unsubstituted C 10 -C 30 wherein the heteroaryl group includes a monocyclic aromatic group or a polycyclic aromatic group containing at least one heteroatom, wherein the heteroatom includes O, S, and N; and Ar1 or Ar2 contains at least one group selected from the following groups: All hydrogen atoms in the general formula (1) may be completely unsubstituted by deuterium, completely substituted by deuterium, or partially substituted by deuterium.

2. The organic electroluminescent compound according to claim 1, characterized in that The Ar1 is selected from the following groups, and the following groups may be further substituted by deuterium: Ar2 is selected from the following groups, and the following groups may be further substituted with deuterium:

3. The organic electroluminescent compound according to claim 1, characterized in that The R1 and R2 are selected from the following groups, and the following groups may be further substituted by deuterium: Where D represents deuterium, Indicates the attachment position of the group.

4. The organic electroluminescent compound according to claim 1, characterized in that The organic electroluminescent compound of general formula (1) is selected from any one of H1-1 to H1-260:

5. An organic electroluminescent material containing a dual host material, characterized in that: The organic electroluminescent material comprises a first host material and a second host material, wherein the first host material is the organic electroluminescent compound according to any one of claims 1 to 4; and the second host material has a compound having a structure represented by general formula (2): wherein L1 to L3 are each independently selected from a connecting bond, a substituted or unsubstituted C6-C 30 Aryl, substituted or unsubstituted C6-C 30 heteroaryl; D1 to D3 are each independently selected from substituted or unsubstituted C6-C 30 Aryl, substituted or unsubstituted C6-C 30 Heteroaryl, substituted or unsubstituted C 10 -C 30 wherein the heteroaryl group is a monocyclic aromatic group or a polycyclic aromatic group including at least one heteroatom, and the heteroatom includes but is not limited to O, S, N, P, and Si.

6. The organic electroluminescent material containing dual host materials according to claim 5, characterized in that: D1 is selected from C6-C 36 Aryl, substituted or unsubstituted C6-C 30 Heteroaryl: A heteroaryl is a monocyclic aromatic group or a polycyclic aromatic group that includes at least one heteroatom, and the heteroatom includes but is not limited to O, S, N, P, and Si.

7. The organic electroluminescent material containing dual host materials according to claim 5, characterized in that: The D1 is selected from the following groups, which can be connected at any substitutable site, and the following groups can be further substituted by deuterium: D2 and D3 are each independently selected from the following substituted or unsubstituted groups: L2 and L3 are each independently selected from a linker, a phenyl group, and a naphthyl group; L1 is selected from the group consisting of a linker, an unsubstituted C6-C 18 Aryl, substituted or unsubstituted C6-C 18 Heteroaryl, wherein the heteroatom is selected from O, S, N, P, Si. The "substituted" is selected from deuterium, cyano, methyl, C6-C 24 Aryl, C6-C 24 Heteroaryl, wherein the heteroatom is selected from O, S, N, P, Si.

8. The organic electroluminescent material containing dual host materials according to claim 5, characterized in that: The second host material has any one of the following structures:

9. An organic electroluminescent device, characterized in that: The organic electroluminescent device comprises the organic electroluminescent material containing a double host according to any one of claims 5 to 8.

10. The organic electroluminescent device according to claim 9, characterized in that: The organic electroluminescent device comprises a first electrode, a hole injection layer, a hole transport layer, a light-emitting layer, a hole blocking layer, an electron transport layer, an electron injection layer, and a second electrode arranged in sequence; the material of the light-emitting layer comprises the organic electroluminescent material containing a dual host according to any one of claims 5 to 8, and further comprises a doping material; The mass ratio of the organic electroluminescent material containing the dual hosts to the doping material in the light-emitting layer is (5-199):1.

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