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

Abstract

The invention belongs to the field of organic electroluminescent materials, and discloses a host material, an organic electroluminescent material containing double hosts and an organic electroluminescent device. The double-host-containing organic electroluminescent material comprises a first host material and a second host material, the first host material is a compound having a structure represented by a general formula (1), and the second host material is a compound having a structure represented by a general formula (2). By changing the molecular configuration of the first host material, a low permanent dipole moment is obtained, and according to the formula P = N [mu] 2E / 3kBT, by controlling the orientation change caused by a smaller dipole moment ([mu]), a smaller dielectric constant and a capacitance reduction result can be obtained, so that the capacitance accumulated in a light-emitting layer is reduced, and a light-emitting diode with a long service life and a low cost is obtained. The invention relates to a low-driving-voltage organic electroluminescent material containing double hosts and an organic electroluminescent device.

Description

Technical Field

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

[0002] Organic electroluminescent devices (OLEDs) can be used to manufacture new display products and new lighting products. The market application prospect is very broad. At present, OLED display technology has been applied to fields such as smart phones and tablet computers. However, compared with the actual product application requirements, the performance of OLEDs such as luminous efficiency and service life still needs to be further improved.

[0003] The OLED structure includes electrode material film layers and organic functional materials sandwiched between different electrode film layers. As a current device, when a voltage is applied to the two electrodes of the OLED, positive and negative charges in the organic layer functional material film layer are separated by the action of an electric field, and the positive and negative charges are further recombined in the light-emitting layer, that is, OLED electroluminescence is generated. Since the radiative transition of triplet excitons in most organic molecules is forbidden and makes little contribution to electroluminescence, by doping with organometallic 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 efficiency of the organic light-emitting device. Therefore, the efficiency of OLEDs can be improved by doping the host and guest in the light-emitting layer. However, triplet-triplet annihilation (TTA) occurs during the transfer of triplet excitons, resulting in energy loss and causing efficiency roll-off of the organic light-emitting device.

[0004] The permanent dipole moment within a molecule is caused by the uneven distribution of electron density due to the difference in electronegativity between atoms within the molecule. Molecules with a large permanent dipole moment will occupy part of the anode and cathode regions. If such a permanent dipole moment exists, it indicates that there are regions with high electron density in the molecule, which will greatly increase the polarity of the molecule. That is, the electric field is affected by the permanent dipole moment and has the effect of strengthening the polarity of the molecule, and can make the dielectric constant higher.

[0005] The permanent dipole moment of organic low molecules has a great influence on the dielectric constant of materials. Some literature points out that by changing the dielectric constant of materials to reduce the capacitance accumulated in the light-emitting layer of devices, it is also very important to obtain products with low capacitance through the design method of molecules with smaller permanent dipole moments. (Reference 1: E. Talebian, M. Talebian*, A general review on the derivation of Clausius–Mossotti relation, Optik 124(2013)2324–2326), (Reference 2: Atkins, Peter; de Paula, Julio, "Chapter 17". Atkins' Physical Chemistry. Oxford University Press. pp. 622–629(2010).)

[0006] Therefore, how to obtain a molecular configuration with a low permanent dipole moment, and then obtain an organic electroluminescent material and an organic electroluminescent device containing a double host with long lifetime and low driving voltage are technical problems that those skilled in the art urgently need to solve. Summary of the Invention

[0007] In view of this, the present invention discloses and provides a host material, an organic electroluminescent material containing a double host, and an organic electroluminescent device. By changing the molecular configuration of the first host material to obtain a low permanent dipole moment, according to the formula P = Nμ 2 E / 3k B T, by controlling the orientation change (Orientational Polarization) caused by a smaller dipole moment (μ), a smaller dielectric constant and a result of capacitance reduction can be obtained, so as to reduce the capacitance accumulated in the light-emitting layer, and obtain an organic electroluminescent material and an organic electroluminescent device containing a double host with long lifetime and low driving voltage.

[0008] In order to achieve the above object, the following technical solutions are adopted:

[0009] The first technical object of the present invention is to provide a host material, and the structural general formula of the host material is shown in formula (1):

[0010]

[0011] Wherein, L is independently selected from a linking bond, a substituted or unsubstituted C6-C12 aryl group;

[0012] R1, R2, and R3 are the same or different from each other, and are each independently selected from a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C3-C30 heterocyclic group, wherein the heteroatom is selected from O, N, S.

[0013] Further, L is independently selected from unsubstituted phenyl, biphenyl, and naphthyl.

[0014] Further, the formula (1) preferably has the following structure:

[0015]

[0016] Wherein, the "substituted" group is selected from one of deuterium, fluorine, C1-C10 alkyl, C1-C10 alkoxy, C3-C10 cycloalkyl, and C6-C12 aryl.

[0017] In the present invention, the C6-C12 aryl may be an aryl of C6, C7, C8, C9, C10, C11, or C12; the C1-C10 alkyl may be an alkyl of C1, C2, C3, C4, C5, C6, C7, C8, C9, or C10; the C1-C10 alkoxy may be an alkoxy of C1, C2, C3, C4, C5, C6, C7, C8, C9, or C10; the C6-C30 aryl may be an aryl of C6, C7, C8, C9, C10, C12, C14, C16, C18, C20, C22, C25, C28, or C30; the C3-C30 heterocyclic group may be a heterocyclic group of C3, C4, C5, C6, C7, C8, C9, C10, C12, C14, C16, C18, C20, C22, C25, C28, or C30; the C3-C10 cycloalkyl may be a cycloalkyl of C3, C4, C5, C6, C7, C8, C9, or C10.

[0018] In the above technical solution, the host material is any one of the following structures, but not limited thereto:

[0019]

[0020]

[0021]

[0022]

[0023]

[0024]

[0025]

[0026]

[0027]

[0028]

[0029]

[0030]

[0031]

[0032]

[0033]

[0034]

[0035]

[0036]

[0037]

[0038]

[0039]

[0040]

[0041]

[0042]

[0043]

[0044]

[0045]

[0046] The above are some specific structural forms of the host material, but not limited to the listed chemical structures. All compounds with simple transformations of groups within the defined ranges based on the structural general formula as shown in formula (1) should be included.

[0047] The second technical objective of the present invention is to provide an organic electroluminescent material containing a double host. The organic electroluminescent material containing a double host includes the above-mentioned host material (the first host material) and a second host material, and the mass ratio of the host material (the first host material) to the second host material is 1:1;

[0048] The structural general formula of the second host material is as shown in formula (2):

[0049]

[0050] Among them, D1, D2, and D3 are each independently selected from substituted or unsubstituted C6-C42 aryl groups and substituted or unsubstituted C3-C30 heteroaryl groups; L1 and L2 are selected from a linking bond, substituted or unsubstituted C6-C30 aryl groups.

[0051] Preferably, D1 and D2 are independently selected from substituted or unsubstituted C6-C18 aryl groups; D3 is selected from substituted or unsubstituted C6-C36 aryl groups and substituted or unsubstituted C3-C30 heteroaryl groups; L1 and L2 are selected from a linking bond, substituted or unsubstituted C6-C18 aryl groups.

[0052] Furthermore, D1 is selected from substituted or unsubstituted phenyl, biphenyl, terphenyl; D2 is selected from substituted or unsubstituted phenyl, naphthyl, biphenyl, terphenyl, benzophenanthryl; D3 is selected from substituted or unsubstituted C6-C30 aryl groups and substituted or unsubstituted C3-C30 heteroaryl groups; L1 is a linking bond, and L2 is a linking bond or phenyl, naphthyl;

[0053] The heteroaryl group includes a monocyclic aromatic group and a polycyclic aromatic system containing at least one heteroatom, and the heteroatom includes but is not limited to O, S, N.

[0054] In the second host material, the "substituted" group in the substituted or unsubstituted is selected from deuterium, fluorine, C1-C10 alkyl, deuterium-substituted C1-C10 alkyl, C3-C10 cycloalkyl, and three- to ten-membered heterocycloalkyl, and its heteroatom is selected from O, S, N; and the "substituted" group in the substituted or unsubstituted can also be selected from the following structures:

[0055]

[0056] 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. The substitution means that the hydrogen atom bonded to the carbon atom of the compound becomes another substituent, and there is no restriction on the substitution position 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 can be the same or different from each other.

[0057] In the above technical solution, the second host material is any one of the following structures, but not limited thereto:

[0058]

[0059]

[0060]

[0061]

[0062]

[0063]

[0064]

[0065]

[0066]

[0067]

[0068] The above are some specific structural forms of the second host material, but not limited to the listed chemical structures. All compounds with a structural general formula as shown in formula (2) and simple transformations of the D1, D2, D3, L1, and L2 groups within the previously defined ranges should be included.

[0069] The present invention also provides a preparation method of the organic electroluminescent material containing a double host, and the specific steps and conditions of this preparation method are as follows:

[0070] I. Preparation method of intermediate:

[0071] (1) Under a nitrogen atmosphere, 1 eq of a dibenzofuran compound, 1 - 2 eq of bis(pinacolato)diboron, 2 - 2.5 eq of potassium acetate, 0.01 - 0.02 eq of tris(dibenzylideneacetone)dipalladium(0), 0.05 - 0.08 eq of 2 - dicyclohexylphosphino - 2',4',6' - triisopropylbiphenyl, and 1,4 - dioxane are successively added to a round - bottom flask, and the temperature is raised to 80 - 100 °C and stirred for reaction for 12 - 24 h. After cooling to room temperature, pure water is added and stirred for 30 - 60 minutes, and a solid precipitates. After filtration, a crude product is obtained; the crude product is successively washed with distilled water, ethanol, and petroleum ether, and then dried to obtain intermediate compound A1 - D1; its synthetic route is as follows:

[0072]

[0073] (2) Under a nitrogen atmosphere, A1 - D1, 1 - 1.2 eq of 2 - bromo - 2'-iodobiphenyl, 2 - 3 eq of potassium carbonate, 0.01 - 0.03 eq of palladium acetate, 0.05 - 0.1 eq of triphenylphosphine, and a mixed solvent of tetrahydrofuran and water with a volume ratio of 3:1 are successively added to a round - bottom flask, and the temperature is raised to 70 °C and stirred for reaction for 12 - 24 h. After cooling to room temperature, pure water is added, stirred for 30 min, and then left to stand for liquid separation. The liquid separation is carried out, and column chromatography is performed using dichloromethane / petroleum ether as the eluent to obtain A2 - D2; its synthetic route is as follows:

[0074]

[0075] (3) Under nitrogen atmosphere, A2-D2, 0.15-0.2eq tris[3,5-bis(trifluoromethyl)phenyl]phosphine, 2-3eq cesium carbonate, 0.05-0.1eq di(cyanobenzene)palladium dichloride, and 1,4-dioxane were added to a round-bottom flask in sequence, and the temperature was raised to 100°C and stirred for reaction for 12-24h. After cooling to room temperature, purified water was added, stirred for 30min, and then allowed to stand for stratification. The liquids were separated and column chromatography was performed using dichloromethane / petroleum ether as the eluent to obtain A3-D3. The synthetic route thereof is as follows:

[0076]

[0077] 2. Synthesis of main materials:

[0078] (1) Under nitrogen atmosphere, weigh 1 eq of reactant 1 containing R3 substituent, 1-1.2 eq of reactant 2 containing R2 substituent, and 2-3 eq of sodium tert-butoxide, and add toluene, 0.02-0.03 eq of tris(dibenzylideneacetone)palladium, and 0.04-0.06 eq of tri-tert-butylphosphine in turn. Under nitrogen protection, reflux at 100-120° C. for 24-36 h, cool to 25° C., add purified water, stir for 30 min, stand for stratification, separate the liquids, use dichloromethane / petroleum ether as eluent, and perform column chromatography to obtain R-1;

[0079] (2) Under nitrogen atmosphere, weigh 1 eq R-1, 1-1.2 eq reactant 3 containing an L substituent, and 2-3 eq sodium tert-butoxide, and add toluene, 0.02-0.04 eq tris(dibenzylideneacetone)palladium, and 0.04-0.06 eq tri-tert-butylphosphine in turn. Under nitrogen protection, reflux at 100-120° C. for 24-48 h, cool to 25° C., add purified water, stir for 30 min, let stand and separate, separate the layers, use dichloromethane / petroleum ether as eluent, and perform column chromatography to obtain R-2;

[0080] (3) Under nitrogen atmosphere, weigh 1 eq of reactant 4 containing an R1 substituent, 1-1.2 eq of R-2, and 2-3 eq of sodium tert-butoxide are added to a reaction flask in sequence, then toluene is added, 0.02-0.04 eq of tris(dibenzylideneacetone)palladium and 0.04-0.06 eq of tri-tert-butylphosphine are added, and under nitrogen protection, reflux at 100-120° C. for 12-24 h, cool to 25° C., add purified water, stir for 30 min, let stand and separate, separate the layers, use dichloromethane / petroleum ether as eluent, and perform column chromatography to obtain R-3;

[0081] (4) Under nitrogen atmosphere, weigh 1 eq of reactant A3-D3, 1-1.2 eq of R-3, and 2-3 eq of sodium tert-butoxide and add them to a reaction flask in sequence, then add toluene, add 0.02-0.03 eq of tris(dibenzylideneacetone)palladium and 0.04-0.06 eq of tri-tert-butylphosphine, reflux at 100-120° C. for 12-24 h under nitrogen protection, cool to 25° C., add purified water, stir for 30 min, let stand to separate, separate the liquids, use dichloromethane / petroleum ether as eluent, and perform column chromatography to obtain the compounds represented by formula (1). The synthesis route thereof is as follows:

[0082]

[0083] 3. Synthesis of the Second Main Material

[0084] (1) Under nitrogen atmosphere, weigh 1 eq of reactant 1, 1-1.2 eq of reactant 2 containing a D1 substituent, 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° C. for 24 h under nitrogen protection, cool to 25° C., filter, and perform solid column chromatography to obtain compound H-1;

[0085] (2) Under nitrogen atmosphere, weigh 1 eq H-1, 1-1.2 eq of reactant 2-1 containing a D2 substituent, and 3-4 eq of potassium carbonate, and add them to the reaction system in sequence, 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 perform solid column chromatography to obtain compound H-2;

[0086] (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, 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 perform solid column chromatography to obtain the compound represented by formula (2). The synthesis route is as follows:

[0087]

[0088] The third technical purpose of the present invention is to provide an application of an organic electroluminescent material containing a double host in the preparation of an organic electroluminescent device.

[0089] The organic electroluminescent device includes a first electrode, an organic electroluminescent material layer, and a second electrode; the organic electroluminescent material layer includes a light-emitting layer, and the light-emitting layer includes a doping material and a dual-host organic electroluminescent material; the mass ratio of the dual-host organic electroluminescent material to the doping material is (1-99):(99-1).

[0090] In the present invention, the organic electroluminescent device includes an anode, a hole transport region, a light-emitting layer, an electron transport region, and a cathode. Specifically,

[0091] The anode material preferably has a material with a large work function to enable holes to 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 not limited thereto.

[0092] The cathode material preferably has a material with a small work function to enable electrons to 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; multi-layer structure materials such as LiF / Al or LiO2 / Al; but not limited thereto.

[0093] 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.

[0094] Among them, the hole injection layer material is a material that receives holes from the anode at a low voltage. 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 materials include metal porphyrins, oligothiophenes, arylamine-based organic materials, hexanitrile hexaazatriphenylene-based organic materials, quinacridone-based organic materials, perylene-based organic materials, anthraquinone, and conductive polymers based on polyaniline and polythiophene.

[0095] The hole transport layer material is a material that can receive holes from the anode or the hole injection layer, transport the holes to the light-emitting layer, and has a high hole mobility. The hole transport layer materials include arylamine-based organic materials, conductive polymers, block copolymers having both a conjugated part and a non-conjugated part, but not limited thereto.

[0096] The electron blocking layer is disposed between the hole transport layer and the light-emitting layer, and the electron blocking layer material includes arylamine-based organic materials.

[0097] 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.

[0098] The electron transport region includes an electron transport layer and an electron injection layer.

[0099] The electron transport layer has the function of promoting electron transport. The electron transport material is a material that receives electrons from the cathode and transports the electrons to the light emitting layer and has a high electron mobility. The electron transport materials include Al complexes of 8-hydroxyquinoline, complexes of Alq3, organic radical compounds, hydroxyflavone-metal complexes, but are not limited thereto. The thickness of the electron transport layer is 1 nm to 50 nm, which can prevent the decline of electron transport characteristics and prevent the increase of driving voltage.

[0100] The electron injection layer has the function of promoting electron injection. The electron injection material is a material that has the ability to transport electrons, 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 has excellent thin film forming ability. The electron injection layer materials include fluorenone, anthraquinone dimethane, biphenylquinone, thiopyran dioxide, oxazole, dioxazole, triazole, imidazole, perylene tetracarboxylic acid, fluoreneylidene methane, anthrone, etc. and their derivatives, metal complexes, nitrogen-containing five-membered ring derivatives, but are not limited thereto.

[0101] In the present invention, the organic electroluminescent device can be a top emission type, a bottom emission type or a double-sided emission type.

[0102] The organic electroluminescent device can be used in organic solar cells, electronic papers, organic photoreceptors or organic thin film transistors.

[0103] Through the above technical solutions, compared with the prior art, the present invention has the following beneficial effects:

[0104] A host organic electroluminescent material disclosed in the present invention is a hole property host material prepared by using a molecular design method with a reduced congenital permanent dipole moment. By adjusting the furan position, the compound is made to have a low permanent dipole moment, and when applied to a device structure, a device structure with a reduced capacitance can be obtained. When applied to an organic electroluminescent device structure, the driving voltage can be effectively reduced, and at the same time, the luminous efficiency and service life of the device can be improved. BRIEF DESCRIPTION OF THE DRAWINGS

[0105] In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required for the description of the embodiments or the prior art. Obviously, the drawings in the following description are only the embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained according to the provided drawings without creative efforts.

[0106] Figure 1 1H NMR spectrum of compound R001 provided in the embodiments of the present invention.

[0107] Figure 2 Comparison chart of dipole moment values between compound R001 provided in the embodiments of the present invention and E-1 provided in Comparative Example 1. Detailed implementation manners

[0108] Next, the technical solutions of the present invention will be clearly and completely described in conjunction with the embodiments of the present invention and the relevant drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative efforts shall fall within the protection scope of the present invention.

[0109] The present invention specifically discloses a host material, an organic electroluminescent material containing a double host, and an organic electroluminescent device.

[0110] It should be noted that the values given in the following embodiments are as accurate as possible. However, those skilled in the art understand that due to inevitable measurement errors and experimental operation problems, each number should be understood as an approximate number rather than an absolutely accurate value.

[0111] Example 1: Preparation of intermediate product A3

[0112] (1) Under a nitrogen atmosphere, 1 eq of 1-bromo-9-chloro-dibenzofuran (CAS: 2179279-83-3), 1.2 eq of bis(pinacolato)diboron (CAS: 73183-34-3), 2 eq of potassium acetate, 0.01 eq of tris(dibenzylideneacetone)dipalladium, 0.08 eq of 2-dicyclohexylphosphino-2',4',6'-triisopropylbiphenyl, and 1,4-dioxane were successively added to a round-bottom flask, and the temperature was raised to 100 °C and stirred for 24 h. After cooling to room temperature, pure water was added and stirred for 30 minutes to precipitate a solid. After filtration, a crude product was obtained. The crude product was successively washed with distilled water, ethanol, and petroleum ether, and then dried to obtain intermediate compound A1. The synthetic route is as follows:

[0113]

[0114] (2) Under nitrogen atmosphere, 1 eq A1, 1.2 eq 2-bromo-2'-iodobiphenyl (CAS: 39655-12-4), 2 eq potassium carbonate, 0.01 eq palladium acetate, 0.05 eq triphenylphosphine, tetrahydrofuran, and water (3:1) were added to a round-bottom flask in sequence, and the temperature was raised to 70°C and stirred for 12 h. After cooling to room temperature, purified water was added, stirred for 30 min, and then allowed to stand for stratification. The liquids were separated and column chromatography was performed using dichloromethane / petroleum ether as the eluent to obtain A2. The synthetic route is as follows:

[0115]

[0116] (3) Under nitrogen atmosphere, 1 eq A2, 0.15 eq tris[3,5-bis(trifluoromethyl)phenyl]phosphine (CAS: 175136-62-6), 2 eq cesium carbonate, 0.1 eq di(cyanobenzene)palladium dichloride, and 1,4-dioxane were added to a round-bottom flask in sequence, and the temperature was raised to 100°C and stirred for reaction for 24 hours. After cooling to room temperature, purified water was added, stirred for 30 minutes, and then allowed to stand for stratification. The liquids were separated and column chromatography was performed using dichloromethane / petroleum ether as eluent to obtain A3 (test value: 352.94, 13.6 g, yield 52%). Its HPLC purity was greater than 99%, and its synthetic route was as follows:

[0117]

[0118] Example 2: Preparation of Compound R001

[0119] Under nitrogen atmosphere, weigh 1eq A3, 1eq N,N,N-triphenyl-1,4-phenylenediamine (cas: 19606-98-5), 2eq sodium tert-butoxide and put them into the reaction system, add toluene, 0.02eq tris(dibenzylideneacetone)palladium and 0.04eq tri-tert-butylphosphine, reflux at 120°C for 24h under nitrogen protection, then cool to 25°C, add purified water, stir for 30min, stand for stratification, separate, column chromatography, and obtain the compound R001 shown (test value: 652.47, 10.0g, yield 76%). Its HPLC purity is greater than 99%, and the synthetic route is as follows:

[0120]

[0121] Example 3: Preparation of Compound R094

[0122] Under nitrogen atmosphere, weigh 1eq C3, 1eq N,N,N-triphenyl-1,4-phenylenediamine (cas: 19606-98-5), 2eq sodium tert-butoxide and put them into the reaction system, add toluene, 0.03eq tris(dibenzylideneacetone)palladium and 0.06eq tri-tert-butylphosphine, reflux at 120°C for 12h under nitrogen protection, then cool to 25°C, add purified water, stir for 30min, stand for stratification, separate, column chromatography, and obtain the compound R094 (test value: 652.38, 8.2g, yield 62.4%). Its HPLC purity is greater than 99%, and the synthesis route is as follows:

[0123]

[0124] Example 4: Preparation of Compound H001

[0125] Under nitrogen atmosphere, weigh 271.14mmol of reactant 1 (CAS: 108-77-0), 813.43mmol of reactant 2 (CAS: 98-80-6), and 813.43mmol of potassium carbonate into the reaction system, add 500ml of toluene, 250ml of ethanol, 250ml of water, and 13.56mmol of tetrakis(triphenylphosphine)palladium, reflux at 90°C for 24h under nitrogen protection, then cool to 25°C, filter, and solid column chromatography to obtain the compound H001 (test value: 309.37, 83.9g, yield 62.2%). Its HPLC purity is greater than 99%, and the synthetic route is as follows:

[0126]

[0127] The synthesis methods of other compounds are the same as those in the above embodiments and are not described in detail here.

[0128] Device Example 1: Preparation of organic electroluminescent device

[0129] 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.

[0130] 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.

[0131] HTL (Hole Transport Layer): Vacuum deposit NPB (i.e., N, N'-diphenyl-N, N'-(1-naphthyl)-1,1'-biphenyl-4,4'-diamine) on the hole injection layer to form the hole transport layer.

[0132] Light-emitting layer: The light-emitting layer includes a first host material R001, 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.

[0133] Introduce the first host compound organic electroluminescent device and the second host compound organic electroluminescent device as hosts into two chambers of a vacuum vapor deposition device respectively, and introduce compound Z1 as a dopant into another chamber; evaporate the two host materials at a rate of 1:1, and simultaneously evaporate the dopant material at different rates, and deposit based on a doping amount of 3 wt% of the total amount of the host and the dopant to form a light-emitting layer with a thickness of 40 nm on the hole transport layer.

[0134] HBL (Hole Blocking Layer): Vacuum deposit bis(2-methyl-8-hydroxyquinolinato-N1,O8)-(1,1'-biphenyl-4-olato)aluminum (BAlq) on the light-emitting layer to form the hole blocking layer.

[0135] ETL (Electron Transport Layer): Vacuum deposit tris(8-hydroxyquinolinato)aluminum (Alq3) on the hole blocking layer to form the electron transport layer.

[0136] EIL (Electron Injection Layer): Vacuum deposit LiF on the electron transport layer to form the electron injection layer.

[0137] Cathode: Evaporate Al on the electron injection layer to form the cathode, and thus an organic electroluminescent device can be obtained.

[0138] Referring to the preparation method of the organic electroluminescent device provided in Device Example 1, respectively select the compounds of the present invention to replace the first host material R001 and the second host material H001 for the evaporation of the host materials, and prepare the organic electroluminescent devices of the corresponding compounds.

[0139] Red light doping material (Z1)

[0140]

[0141] Device Examples 2-20, Comparative Examples 1-9 and Parallel Examples 1-8:

[0142] The device manufacturing processes of Device Example 2-20, Comparative Example 1-9, and Parallel Example 1-8 are exactly the same, and the same substrate material and electrode material are used, and the film thickness of the electrode material is also kept consistent. The differences are as follows: The two host materials are different, and the corresponding first host material and second host material in Table 1 are selected respectively. The specific parameters are as follows:

[0143] Table 1

[0144]

[0145]

[0146] The structure of the comparative example is as follows:

[0147]

[0148]

[0149] Performance detection: At a brightness of 5000 (nits), the driving voltage, luminous efficiency, and lifetime of the organic light-emitting devices obtained from the above Comparative Example 1-9, Parallel Example 1-8, and Device Example 1-20 are characterized. The test results are shown in Table 2 below.

[0150] Table 2

[0151]

[0152]

[0153] It can be seen from Table 2 that the Device Examples 1-20 provided by the present invention have the advantages of low driving voltage, high luminous efficiency, and long lifetime compared with Parallel Examples 1-8 and Comparative Examples 1-9.

[0154] From this, it can be known that the organic light-emitting material containing a double host provided by the present invention can effectively reduce the driving voltage and improve the luminous efficiency and service life of the device after being applied to the organic light-emitting device.

[0155] The above description of the disclosed embodiments enables those skilled in the art to implement or use the present invention. Various modifications to these embodiments will be obvious to those skilled in the art, and the general principles defined herein can be implemented in other embodiments without departing from the spirit or scope of the present invention. Therefore, the present invention will not be limited to these embodiments shown herein, but will be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. A main body material, characterized in that, The structural general formula of the host material is shown in Formula (1): Wherein, L is independently selected from a linking bond, a substituted or unsubstituted C6-C12 aryl group; R1, R2, and R3 are the same as or different from each other, and are each independently selected from a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C3-C30 heterocyclic group, wherein the heteroatom is selected from O, N, S.

2. The main material according to claim 1, characterized in that, The host material is selected from the following structures:

3. The main material according to claim 1 or 2, characterized in that, L is independently selected from an unsubstituted phenyl group, a biphenyl group, and a naphthyl group.

4. The main material according to claim 1, characterized in that, The host material includes, but is not limited to, any one of the following compounds:

5. An organic electroluminescent material containing a dual host, characterized in that, The organic electroluminescent material containing a double host includes a first host material and a second host material, and the mass ratio of the first host material to the second host material is 1:1; The first host material is the host material as described in Claim 1, and the structural general formula of the second host material is shown in Formula (2): Wherein, D1, D2, and D3 are each independently selected from a substituted or unsubstituted C6-C42 aryl group, a substituted or unsubstituted C3-C30 heteroaryl group; L1 and L2 are selected from a linking bond, a substituted or unsubstituted C6-C30 aryl group.

6. The organic electroluminescent material containing a dual host according to claim 5, characterized in that, D1 and D2 are independently selected from a substituted or unsubstituted C6-C18 aryl group; D3 is selected from a substituted or unsubstituted C6-C36 aryl group, a substituted or unsubstituted C3-C30 heteroaryl group; L1 and L2 are selected from a linking bond, a substituted or unsubstituted C6-C18 aryl group.

7. The dual-host organic electroluminescent material according to claim 6, wherein D1 is selected from a substituted or unsubstituted phenyl group, a biphenyl group, and a terphenyl group; D2 is selected from a substituted or unsubstituted phenyl group, a naphthyl group, a biphenyl group, a terphenyl group, and a benzophenanthryl group; D3 is selected from a substituted or unsubstituted C6-C30 aryl group, a substituted or unsubstituted C3-C30 heteroaryl group; L1 is a linking bond, and L2 is a linking bond or a phenyl group or a naphthyl group; The heteroaryl group includes a monocyclic aromatic group and a polycyclic aromatic system containing at least one heteroatom, and the heteroatom includes, but is not limited to, O, S, N.

8. The organic electroluminescent material containing a dual host according to claim 5, characterized in that, The structure of the second host material includes, but is not limited to, any one of the following compounds:

9. An organic electroluminescent device, characterized in that, The organic electroluminescent device contains the organic electroluminescent material containing a double host as described in Claim 5.

10. The organic electroluminescent device according to claim 9, characterized in that, The organic electroluminescent device includes a first electrode, an organic electroluminescent material layer, and a second electrode; and, the organic electroluminescent material layer includes a light-emitting layer; the light-emitting layer includes a doping material and the organic electroluminescent material containing a double host; the mass ratio of the light-emitting material to the doping material is (1-99):(99-1).

Images