Host material, organic electroluminescent material containing double hosts and organic electroluminescent device

Abstract

The invention provides a main body material, an organic electroluminescent material containing double main bodies and an organic electroluminescent device, and belongs to the field of organic electroluminescent materials, the main body material has a structure shown in a formula (1), the organic electroluminescent material containing double main bodies comprises a first main body material and a second main body material, the first main body material is a main body material with a structure as shown in a formula (1), and the second main body material is a structure as shown in a formula (2). According to the invention, triplet excitons are dispersed on two main bodies by using a double-main-body material, triplet-triplet annihilation is reduced, the driving voltage of the organic electroluminescent device is reduced, the luminous efficiency of the device can be improved, and the service life of the device can be prolonged.

Description

Technical Field

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

[0002] Organic light-emitting diodes (OLEDs) have been widely used in emerging display products (such as smartphones and tablets) and have gradually penetrated into new lighting fields. However, despite the huge market potential, current OLED technology still faces significant challenges in terms of luminous efficiency and service life, and there is still a gap between the actual product application requirements.

[0003] The basic structure of OLED includes an electrode material layer and an organic functional material layer sandwiched between the electrodes. When a voltage is applied to the electrodes at both ends of the OLED, the electric field causes the positive and negative charges in the organic layer to separate, and these charges then recombine in the light-emitting layer to generate electroluminescence. However, since the triplet exciton radiative transition of most organic molecules is forbidden, their contribution to electroluminescence is limited. Therefore, by doping with organic metal complexes such as platinum, iridium, and osmium, the triplet excitons of organic molecules can be transferred to the triplet state of the metal complex, thereby improving the luminescence efficiency of the device. Nevertheless, triplet-triplet annihilation (TTA) may occur during the transfer process of triplet excitons, resulting in energy loss and causing the device efficiency to roll off.

[0004] At present, organic electroluminescent devices still have problems such as too high driving voltage, low luminous efficiency and short life in actual use. These technical bottlenecks limit their application in a wider range of fields. Therefore, the development of a dual-host organic electroluminescent material with long life and low driving voltage, its preparation method and organic electroluminescent device has become a key issue to be solved in current technology research and development. This can not only optimize the performance of existing OLEDs, but also provide technical support for further innovation of new display and lighting products. Summary of the invention

[0005] In view of the shortcomings of the prior art, the object of the present invention is to provide a host material, an organic electroluminescent material containing a double host, and an organic electroluminescent device.

[0006] To achieve this object, the present invention adopts the following technical solutions:

[0007] In one aspect, the present invention provides a host material having a structure as shown in formula (1):

[0008]

[0009] Wherein, R1 and R2 are independently selected from C6-C30 aryl groups which may be substituted or unsubstituted by deuterium, and substituted or unsubstituted C6-C30 arylamine groups;

[0010] The hydrogen in the compound of formula (1) may be completely or partially substituted by deuterium.

[0011] Furthermore, the main material is a compound having any of the following structures:

[0012]

[0013] Furthermore, the main material is a compound having any of the following structures:

[0014]

[0015] R1 and R2 are independently selected from C6-C18 aryl groups which may be substituted or unsubstituted by deuterium or

[0016] Wherein, the attachment site of the group is any substitutable position, and R3-R8 is selected from hydrogen, deuterium, fluorine, phenyl, naphthyl, biphenyl, methyl, ethyl, propyl, butyl;

[0017] Preferably, R1 and R2 are independently selected from phenyl, naphthyl, anthracenyl, phenanthrenyl, biphenyl, terphenyl, pyrenyl, chrysene, phenylnaphthyl, 9,9-dimethylfluorenyl, triphenylene, deuterated phenyl, deuterated terphenyl and any one of the following groups:

[0018]

[0019] The attachment point of the above-mentioned groups is any substitutable position.

[0020] As a preferred technical solution, the main material is any one of the following structures, but not limited thereto:

[0021]

[0022]

[0023]

[0024]

[0025]

[0026]

[0027]

[0028]

[0029]

[0030]

[0031]

[0032]

[0033]

[0034]

[0035]

[0036]

[0037]

[0038]

[0039]

[0040]

[0041]

[0042] The above are some specific structural forms of the main materials, but they are not limited to the listed chemical structures. All compounds with simple changes of groups within the defined range based on the general structural formula as shown in formula (1) should be included.

[0043] The second technical purpose of the present invention is to provide an organic electroluminescent material containing a double host, wherein the organic electroluminescent material containing a double host comprises a first host material and a second host material, wherein the first host material is the host material as described above, and the mass ratio of the first host material to the second host material is 1-5:1-5; for example, 1:1, 2:1, 3:1, 4:1, 5:1, 1:2, 1:3, 1:4, 1:5, 2:3, 2:5, 3:2, 3:4, 3:5, 4:3, 4:5, 5:2, 5:3, 5:4, etc., preferably 1:1;

[0044] The second host material has a structure as shown in formula (2):

[0045]

[0046] Wherein, D1, D2, and D3 are each independently selected from substituted or unsubstituted C6-C42 aryl, substituted or unsubstituted C3-C30 heteroaryl;

[0047] L1 and L2 are a connecting bond, a substituted or unsubstituted C6-C30 aryl group.

[0048] The present invention disperses triplet excitons on two hosts by using a double host material, thereby reducing triplet-triplet annihilation (TTA), thereby reducing the driving voltage of the organic electroluminescent device and improving the luminous efficiency and service life of the device.

[0049] Preferably, D1 and D2 are selected from C6-C18 substituted or unsubstituted aryl groups;

[0050] D3 is selected from substituted or unsubstituted C6-C36 aryl, substituted or unsubstituted C3-C30 heteroaryl;

[0051] L1 and L2 are selected from a connecting bond, a C6-C18 substituted or unsubstituted aryl group.

[0052] Further, D1 is selected from substituted or unsubstituted phenyl, biphenyl, terphenyl;

[0053] D2 is selected from substituted or unsubstituted phenyl, naphthyl, biphenyl, terphenyl, triphenylene;

[0054] D3 is selected from substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl;

[0055] L1 is a connecting bond, and L2 is a connecting bond or a phenyl group, a naphthyl group, or a biphenyl group.

[0056] As a preferred technical solution, the second main material is any one of the following structures, but not limited thereto:

[0057]

[0058]

[0059]

[0060]

[0061]

[0062]

[0063]

[0064]

[0065]

[0066]

[0067]

[0068] The above are some specific structural forms of the second host material, but are not limited to the listed chemical structures. All compounds based on the general structural formula shown in formula (2) and where the D1, D2, L1 and L2 groups are simple changes of the groups within the previously defined range should be included.

[0069] The “heteroaryl” includes monocyclic aromatic groups and polycyclic aromatic systems having at least one heteroatom, and the heteroatoms include but are not limited to O, S, and N.

[0070] Wherein, the "substituted" group is selected from hydrogen, deuterium, fluorine, phenyl, naphthyl, biphenyl, methyl, ethyl, propyl, butyl, C1-C10 alkyl, C1-C10 alkoxy, C3-C10 cycloalkyl, methyl, C6-C12 aryl, three-membered to ten-membered heterocycloalkyl, and its heteroatom is selected from O, S, N, and the substituted or unsubstituted group can also be selected from the following structures:

[0071]

[0072] The dashed lines represent the attachment sites of the groups.

[0073] It should be noted that the substituted or unsubstituted means that the group may not be substituted or may be substituted by one or more substituents, and the substitution means that the hydrogen atom bonded to the carbon atom of the compound is changed into another substituent, and the position of the substitution is not limited, as long as the position is the position where the hydrogen atom is substituted, that is, the position where the substituent can be substituted, and when two or more substituents are substituted, the two or more substituents may be the same as or different from each other.

[0074] The present invention also provides a method for preparing the first host material and the second host material. The specific steps and conditions of the preparation method are as follows:

[0075] 1. Preparation method of intermediate product:

[0076] (1) Under nitrogen atmosphere, 1 eq. of reactant 1, 1 eq. of reactant 2, 2 eq. of potassium carbonate, toluene, ethanol, and water (5:2:1) were added to a round-bottom flask in sequence, and stirred for 10 min. Then, 0.05 eq. of tetrakis(triphenylphosphine)palladium was added, and the temperature was raised to 120° C. and stirred for 18 h. After cooling to room temperature, the organic phase was separated by extraction, dried over anhydrous magnesium sulfate, and distilled under reduced pressure to obtain a crude product. Dichloromethane / petroleum ether was used as an eluent, and the crude product was purified by silica gel column chromatography to obtain intermediate-1 or intermediate-2

[0077]

[0078] (2) Under nitrogen atmosphere, the intermediate-1 or intermediate-2 was dissolved in 60 times dichloromethane, 5 eq. ferric chloride and 2 times nitromethane were added, and after stirring for 1 hour, 10 times methanol was added, and the organic phase was extracted and separated, and dried over anhydrous magnesium sulfate, and distilled under reduced pressure to obtain a crude product. Dichloromethane / petroleum ether was used as an eluent, and the crude product was purified by silica gel column chromatography to obtain intermediate-3 or intermediate-4.

[0079]

[0080] 2. Synthesis of the first main material:

[0081] Under nitrogen atmosphere, weigh 1 eq. of intermediate-3 or intermediate-4, 1 eq. of diarylamine compounds, 2.5 eq. of sodium tert-butoxide, toluene, 0.03 eq. of tris(dibenzylideneacetone)palladium and 0.06 eq. of tricyclohexylphosphine in a three-necked flask, reflux at 120°C under nitrogen protection, cool to 25°C, solid precipitates, filter to obtain a crude product, wash the crude product with toluene and tetrahydrofuran in turn, and dry to obtain formula (1)-1 or formula (1)-2

[0082]

[0083]

[0084] 3. Combination of the Second Main Material

[0085] (1) Under nitrogen atmosphere, 1 eq. 2,4,6-trichloro-1,3,5-triazine, 2-3 eq. arylboronic acid, and 3.5 eq. potassium carbonate were weighed and added to the reaction system in sequence, and then toluene, ethanol, water (2:1:1) and 0.05-0.08 eq. tetrakis(triphenylphosphine)palladium were added. The mixture was refluxed at 90° C. for 24 h under nitrogen protection, cooled to 25° C., and the organic phase was separated by extraction. The phase was dried over anhydrous magnesium sulfate and distilled under reduced pressure to obtain a crude product. Dichloromethane / petroleum ether was used as an eluent, and the crude product was purified by silica gel column chromatography to obtain compound H-1.

[0086]

[0087] (2) Under nitrogen atmosphere, weigh 1 eq. H-1, 1-1.2 eq. arylboronic acid containing D2 substituent, and 3-4 eq. potassium carbonate and add them to the reaction system in sequence, then add toluene, ethanol, water (2:1:1) and 0.05-0.08 eq. tetrakis(triphenylphosphine)palladium. Reflux at 90-100° C. for 24 h under nitrogen protection, cool to 25° C., filter, and purify the crude solid by silica gel column chromatography using dichloromethane / petroleum ether as eluent to obtain compound H-2.

[0088]

[0089] (3) Under nitrogen atmosphere, weigh 1 eq H-2, 1-1.2 eq of reactant containing D3 substituent 2-2, and 3-4 eq of potassium carbonate and add them to the reaction system in sequence, then add toluene, ethanol, water (2:1:1) and 0.05-0.08 eq of tetrakis(triphenylphosphine)palladium. Reflux at 90-100° C. for 24 h under nitrogen protection, cool to 25° C., filter, and purify the crude solid by silica gel column chromatography using dichloromethane / petroleum ether as eluent to obtain compound H.

[0090]

[0091] The present invention conducts a series of palladium-catalyzed coupling reactions, which utilize the difference in activity I>Br>Cl on the one hand, and control the reaction site by controlling the reaction conditions on the other hand, and purify the reaction by column chromatography or silica gel funnel to remove by-products to obtain the target compound.

[0092] For raw materials that are not disclosed, those skilled in the art can use the classic Suzuki coupling reaction, Buchwald–Hartwig coupling reaction, butyl lithium reaction, and apply them to the present invention. In addition, it should be noted that other compounds of the present application can be obtained by referring to the synthesis methods listed above, so they are not listed one by one here.

[0093] The third technical purpose of the present invention is to provide an organic electroluminescent device containing a dual host, wherein the organic electroluminescent device comprises a first electrode, an organic electroluminescent material layer, and a second electrode; the organic electroluminescent material layer comprises a light-emitting layer, and the light-emitting layer comprises a doping material and the organic electroluminescent material containing a dual host as described above.

[0094] Preferably, the mass ratio of the organic electroluminescent material containing a double host to the doping material is (1-99):(99-1), for example, 1:99, 2:98, 5:95, 8:92, 10:90, 15:85, 20:80, 25:75, 30:70, 35:65, 38:62, 40:60, 45:55, 50:50, 55:45, 58:42, 60:40, 65:35, 70:30, 75:25, 80:20, 85:15, 88:12, 90:10, 95:5, 98:2 or 99:1, etc.

[0095] In the present invention, the organic electroluminescent device comprises an anode, a hole transport region, a light emitting layer, an electron transport region and a cathode. Specifically,

[0096] The anode material preferably has a material with a large work function so that holes can be smoothly injected into the organic material layer. The anode material includes: metals: such as vanadium, chromium, copper, zinc and gold, or their alloys; metal oxides, such as zinc oxide, indium oxide, indium tin oxide (ITO) and indium zinc oxide (IZO); combinations of metals and oxides, such as ZnO:Al or SnO2:Sb; conductive polymers, such as poly(3-methylthiophene), poly[3,4-(ethylene-1,2-dioxy)thiophene] (PEDOT), polypyrrole and polyaniline, but are not limited thereto.

[0097] The cathode material preferably has a material with a small work function so that electrons can be smoothly injected into the organic material layer. The cathode material includes: metals: such as magnesium, calcium, sodium, potassium, titanium, indium, yttrium, lithium, gadolinium, aluminum, silver, tin and lead, or their alloys; multilayer structure materials, such as LiF / Al or LiO2 / Al; but not limited to these.

[0098] The hole transport region includes a hole injection layer, a hole transport layer, an electron blocking layer and a hole blocking layer, and the light emitting layer is located between the electron blocking layer and the hole blocking layer.

[0099] Wherein, the hole injection layer material is a material that receives holes from the anode at a low voltage, and the highest occupied molecular orbital (HOMO) of the hole injection material is preferably between the work function of the anode material and the HOMO of the surrounding organic material layer. The hole injection material includes metal porphyrin, oligothiophene, organic materials based on arylamine, organic materials based on hexanitrile hexaazatriphenylene, organic materials based on quinacridone, organic materials based on perylene, anthraquinone, and conductive polymers based on polyaniline and polythiophene.

[0100] The hole transport layer material is a material that can receive holes from the anode or the hole injection layer and transport the holes to the light-emitting layer and has high hole mobility. The hole transport layer material includes an organic material based on arylamine, a conductive polymer, and a block copolymer having both a conjugated part and a non-conjugated part, but is not limited thereto.

[0101] The electron blocking layer is disposed between the hole transport layer and the light emitting layer, and the electron blocking layer material includes an arylamine-based organic material.

[0102] The hole blocking layer is disposed between the hole transport layer and the light emitting layer, and the hole blocking layer material includes a triazine-based compound.

[0103] The electron transport region includes an electron transport layer and an electron injection layer.

[0104] The electron transport layer has the function of promoting electron transport. The electron transport material is a material with high electron mobility that receives electrons from the cathode and transports the electrons to the light-emitting layer. The electron transport material includes an Al complex of 8-hydroxyquinoline, a complex of Alq3, an organic free radical compound, and a hydroxyflavone-metal complex, but is not limited thereto. The thickness of the electron transport layer is 1 nm to 50 nm, which can prevent the electron transport characteristics from decreasing and prevent the driving voltage from increasing.

[0105] The electron injection layer has the function of promoting electron injection, and the electron injection material is a material that has the ability to transport electrons, has 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 has excellent thin film forming ability. The electron injection layer material includes fluorenone, anthraquinone dimethane, diphenoquinone, thiopyran dioxide, azole, diazole, triazole, imidazole, perylene tetracarboxylic acid, fluorenyl methane, anthrone, etc. and their derivatives, metal complexes, nitrogen-containing five-membered ring derivatives, but is not limited thereto.

[0106] In the present invention, the organic electroluminescent device may be a top emission type, a bottom emission type or a double-side emission type.

[0107] The organic electroluminescent device can be used in organic solar cells, electronic paper, organic photoreceptors or organic thin film transistors.

[0108] Compared with the prior art, the present invention has the following beneficial effects:

[0109] In the main material disclosed in the present invention, when the triarylamine compound is at the 3rd or 4th position of the furan ring, the structure tends to be planar, resulting in the lowest T1 energy and slower mobility; so that the prepared device has low driving voltage, long life and high luminous efficiency.

[0110] The invention discloses an organic electroluminescent material containing a double host, comprising a first host material and a second host material. By using the double host material, triplet excitons can be dispersed on two hosts, thereby reducing triplet-triplet annihilation (TTA). When applied to an organic electroluminescent device, the driving voltage can be effectively reduced, while the luminous efficiency and service life of the device can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0111] Figure 1 This is the hydrogen NMR spectrum of R045. DETAILED DESCRIPTION

[0112] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0113] 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.

[0114] Example 1: Preparation of intermediate product A2

[0115] Under a nitrogen atmosphere, 160.3 mmol 2-bromo-4-chloro-1,1'-biphenyl, 160.3 mmol 2-(dibenzofuran-2-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane, 320.6 mmol potassium carbonate, 500 ml toluene, 250 ml ethanol, and 100 ml water were added to a round-bottom flask in sequence. After stirring for 10 min, 8 mmol tetrakis(triphenylphosphine)palladium was added, the temperature was raised to 120 ° C, and the reaction was stirred for 18 h. After cooling to room temperature, the organic phase was separated by extraction, dried over anhydrous magnesium sulfate, and distilled under reduced pressure to obtain a crude product. Dichloromethane / petroleum ether was used as the eluent, and the volume ratio of DCM:PE was 1:4. The crude product was purified by silica gel column chromatography to obtain 16.18 g of the intermediate compound A2-1 product with a yield of 25.3%.

[0116]

[0117] Under nitrogen atmosphere, the intermediate compound A2-1 was dissolved in 970 ml of dichloromethane, and 202.7 mmol of ferric chloride and 33 ml of nitromethane were added. After stirring for 1 h, 162 ml of methanol was added, and the organic phase was extracted and separated, dried over anhydrous magnesium sulfate, and distilled under reduced pressure to obtain a crude product. Dichloromethane / petroleum ether was used as eluent, and the volume ratio of DCM:PE was 1:5. The crude product was purified by silica gel column chromatography to obtain intermediate compound A2, 8.69 g of product, and a yield of 54.1%.

[0118]

[0119] Example 2: Preparation of intermediate products A1, A3, A4

[0120] The synthesis methods of intermediate products A1, A3, and A4 are the same as that of A2. The raw material compounds 1 and 2 used and the corresponding product structures are shown in Table 1.

[0121] Table 1

[0122]

[0123]

[0124] Example 3: Preparation of intermediate product B3

[0125] Under nitrogen atmosphere, 160.3mmol 1,4-dibromobiphenyl, 160.3mmol 2-(dibenzofuran-3-yl)-4,4,5,5-tetramethyl-1,3,2-dioxaborolane, 320.6mmol potassium carbonate, 500ml toluene, 250ml ethanol, and 100ml water were added to a round-bottom flask in sequence. After stirring for 10min, 8mmol tetrakis(triphenylphosphine)palladium was added, the temperature was raised to 120°C and stirred for 18h. After cooling to room temperature, the organic phase was separated by extraction, dried over anhydrous magnesium sulfate, and distilled under reduced pressure to obtain a crude product. Dichloromethane / petroleum ether was used as the eluent, and the volume ratio of DCM:PE was 1:5. The crude product was purified by silica gel column chromatography to obtain 17.6g of the intermediate compound B3-1 product with a yield of 27.2%.

[0126]

[0127] Under nitrogen atmosphere, the intermediate compound B3-1 was dissolved in 1.05L dichloromethane, 220.6mmol ferric chloride and 36ml nitromethane were added, and after stirring for 1h, 176ml methanol was added, and the organic phase was extracted and separated, dried over anhydrous magnesium sulfate, and distilled under reduced pressure to obtain a crude product. Dichloromethane / petroleum ether was used as eluent, and the volume ratio of DCM:PE was 1:5. The crude product was purified by silica gel column chromatography to obtain 8.35g of the intermediate compound B3 product with a yield of 47.6%.

[0128]

[0129] Example 4: Preparation of intermediate products B1, B2, B4

[0130] The synthesis methods of intermediate products B1, B2, and B4 are the same as that of B3-2. The raw material compounds 1 and 2 used and the corresponding product structures are shown in Table 2.

[0131] Table 2

[0132]

[0133]

[0134] Example 5: Preparation of Compound R045

[0135]

[0136] Under nitrogen atmosphere, 19.67 mmol of A3, 19.67 mmol of diphenylamine, 49.17 mmol of sodium tert-butoxide, 110 ml of toluene, 0.59 mmol of tris(dibenzylideneacetone)palladium and 1.18 mmol of tricyclohexylphosphine were weighed and added into a three-necked flask in sequence. Under nitrogen protection, the mixture was refluxed at 120°C and cooled to 25°C. Solid precipitated and was filtered to obtain a crude product. The crude product was washed with toluene and acetone in sequence and dried to obtain compound R045; yield: 7.4 g, yield: 77.76%, HPLC purity greater than 99%.

[0137] Mass spectrometry test value: 485.28.

[0138] The H NMR spectrum of R045 is as follows Figure 1 shown.

[0139] Example 6: Preparation of Compound H001

[0140]

[0141] Under nitrogen atmosphere, 271.14 mmol triazine, 813.43 mmol phenylboric acid, and 813.43 mol potassium carbonate were weighed into the reaction system, and 500 ml toluene, 250 ml ethanol, 250 ml water, and 13.56 mmol catalyst tetrakis(triphenylphosphine)palladium were added. The mixture was refluxed at 90° C. for 24 h under nitrogen protection, and then cooled to 25° C., filtered, and subjected to solid column chromatography to obtain the compound H001 with a yield of 62.2% and an HPLC purity of more than 99%.

[0142] Mass spectrometry test value: 309.45.

[0143] The following compounds were synthesized by referring to the synthesis method of the embodiment of the present invention, and their molecular formula and mass spectrum are shown in Table 3. The mass spectrometer model used for mass spectrometry in this application is Waters XEVO TQD, low precision, ESI source test.

[0144] Table 3

[0145]

[0146]

[0147] Application example: Preparation of organic electroluminescent devices

[0148] Device Example 1:

[0149] ITO anode: The coating thickness is The ITO (indium tin oxide) glass substrate was cleaned twice in distilled water, ultrasonically cleaned for 30 minutes, and then repeatedly cleaned twice with distilled water and ultrasonically cleaned for 10 minutes. After washing, it was ultrasonically cleaned with methanol, acetone, and isopropanol for 5 minutes in sequence, dried, and then transferred to a plasma cleaning machine for washing for 5 minutes to obtain an ITO anode.

[0150] HIL (hole injection layer): 4,4',4'-tris(N-3-methylphenyl-N-phenylamino)triphenylamine (m-MTDATA) was vacuum-deposited on the ITO anode in a vapor deposition machine. A hole injection layer is formed.

[0151] HTL (hole transport layer): vacuum evaporation of NPB (i.e. N, N'-diphenyl-N, N'-(1-naphthyl)-1, 1'-biphenyl-4, 4'-diamine) on the hole injection layer A hole transport layer is formed.

[0152] Light-emitting layer: The light-emitting layer includes a first host material R025, a second host material H001 and a guest dopant. After the hole injection layer and the hole transport layer are formed, the light-emitting layer is formed on the hole transport layer.

[0153] The first host compound organic electroluminescent device and the second host compound organic electroluminescent device were introduced as hosts into two small chambers of a vacuum vapor deposition device respectively, and compound Z1 was introduced as a dopant into another small chamber; the two host materials were evaporated at the mass specific gravity in Table 4, and the dopant material was evaporated simultaneously at different rates, and a doping amount of 3wt% based on the total amount of the host and the dopant was deposited to form a light-emitting layer with a thickness of 40nm on the hole transport layer.

[0154] HBL (hole blocking layer): Vacuum evaporation of bis(2-methyl-8-hydroxyquinoline-N1,O8)-(1,1'-biphenyl-4-hydroxy)aluminum (BAlq) on the light-emitting layer A hole blocking layer is formed.

[0155] ETL (Electron Transport Layer): Vacuum evaporation of 8-hydroxyquinoline aluminum (Alq3) on the hole blocking layer An electron transport layer is formed.

[0156] EIL (Electron Injection Layer): Vacuum deposition on the electron transport layer An electron injection layer is formed.

[0157] Cathode: Evaporation on the electron injection layer Al is added to form a cathode to obtain an organic electroluminescent device.

[0158] Referring to the organic electroluminescent device and its preparation method provided in Device Application Example 1, the compounds of the present invention are selected to replace the first host compound organic electroluminescent device and the second host compound organic electroluminescent device for evaporation of the host material to prepare organic electroluminescent devices of the corresponding compounds.

[0159] The structure of the red light doping material (Z1) is as follows:

[0160]

[0161] Device Examples 2-20, Comparative Examples 1-9 and Device Examples 1-8:

[0162] The device manufacturing processes of device embodiments 2-20, comparison examples 1-9 and device embodiments 1-8 are exactly the same, and the same substrate materials and electrode materials are used. The film thickness of the electrode materials is also consistent. The difference is that the two main materials are different, and the corresponding first main compound and second main compound in Table 1 are selected respectively. The specific parameters are shown in Table 4.

[0163] Table 4

[0164]

[0165]

[0166] The material structures involved in the comparative examples are shown in Table 5 below.

[0167] Table 5

[0168]

[0169]

[0170]

[0171] Performance testing: The driving voltage, luminous efficiency and life of the organic electroluminescent devices obtained in the above-mentioned comparative examples 1-9, parallel examples 1-8 and device embodiments 1-20 were characterized at a brightness of 15000 (nits). The test results are shown in Table 6 below.

[0172] Table 6

[0173]

[0174]

[0175] It can be seen from Table 4 that the driving voltage of the organic electroluminescent devices provided by device embodiments 1-20 of the present invention and parallel examples 1-8 is significantly lower than the driving voltage of comparative examples 1-9, and the luminous efficiency and lifespan are significantly improved compared with comparative examples 1-9.

[0176] The applicant declares that the present invention illustrates the process method of the present invention through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned process steps, that is, it does not mean that the present invention must rely on the above-mentioned process steps to be implemented. Those skilled in the art should understand that any improvement of the present invention, equivalent replacement of the raw materials selected by the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A main material, characterized in that: The main material has a structure as shown in formula (1): Wherein, R1 and R2 are independently selected from C6-C30 aryl groups which are substituted or unsubstituted by deuterium, and C6-C30 arylamine groups which are substituted or unsubstituted; and hydrogen in the compound of formula (1) is not substituted by deuterium, is fully substituted by deuterium, or is partially substituted by deuterium.

2. The main body material according to claim 1, characterized in that The main material is a compound having any of the following structures:

3. The main body material according to claim 1, characterized in that The main material is a compound having any of the following structures: Wherein, R1 and R2 are independently selected from C6-C18 aryl groups substituted or unsubstituted by deuterium or Wherein, the connection site of the group is any substitutable position, and R3-R8 is selected from hydrogen, deuterium, fluorine, phenyl, naphthyl, biphenyl, methyl, ethyl, propyl, and butyl.

4. The main body material according to any one of claims 1 to 3, characterized in that R1 and R2 are independently selected from phenyl, naphthyl, anthracenyl, phenanthrenyl, biphenyl, terphenyl, pyrenyl, chrysene, phenylnaphthyl, 9,9-dimethylfluorenyl, triphenylene, deuterated phenyl, deuterated terphenyl and any one of the following groups: The attachment point of the above-mentioned groups is any substitutable position.

5. The main body material according to claim 1, characterized in that The main material is any one of the following compounds:

6. An organic electroluminescent material containing a double host, characterized in that: The organic electroluminescent material containing two hosts comprises a first host material and a second host material, wherein the first host material is the host material according to any one of claims 1 to 5, and the mass ratio of the first host material to the second host material is 1-5:1-5; The second host material has a structure as shown in formula (2): Wherein, D1, D2, and D3 are each independently selected from substituted or unsubstituted C6-C42 aryl, substituted or unsubstituted C3-C30 heteroaryl; L1 and L2 are a connecting bond, a substituted or unsubstituted C6-C30 aryl group.

7. The organic electroluminescent material containing a double host according to claim 6, characterized in that: D1 and D2 are selected from C6-C18 substituted or unsubstituted aryl groups; D3 is selected from substituted or unsubstituted C6-C36 aryl, substituted or unsubstituted C3-C30 heteroaryl; L1 and L2 are selected from a connecting bond, a C6-C18 substituted or unsubstituted aryl group.

8. The organic electroluminescent material containing a double host according to claim 7, characterized in that: D1 is selected from substituted or unsubstituted phenyl, biphenyl, terphenyl; D2 is selected from substituted or unsubstituted phenyl, naphthyl, biphenyl, terphenyl, triphenylene; D3 is selected from substituted or unsubstituted C6-C30 aryl, substituted or unsubstituted C3-C30 heteroaryl; L1 is a connecting bond, and L2 is a connecting bond or a phenyl group, a naphthyl group, or a biphenyl group.

9. The organic electroluminescent material containing a double host according to claim 6, characterized in that: The second host material is any one of the following compounds:

10. An organic electroluminescent device containing a double host, characterized in that: The organic electroluminescent device comprises a first electrode, an organic electroluminescent material layer, and a second electrode; the organic electroluminescent material layer comprises a light-emitting layer, and the light-emitting layer comprises a doping material and the organic electroluminescent material containing a dual host according to any one of claims 6 to 9; The mass ratio of the organic electroluminescent material containing the dual host and the doping material is (1-99):(99-1); The organic electroluminescent material layer further comprises a hole transport region and an electron transport region; The hole transport region includes a hole injection layer, a hole transport layer, an electron blocking layer and a hole blocking layer, and the light emitting layer is located between the electron blocking layer and the hole blocking layer; The electron transport region includes an electron transport layer and an electron injection layer.

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