Triazinyl compound, OLED (Organic Light Emitting Diode) with same and organic light emitting device

Abstract

The invention relates to the technical field of preparation of organic photoelectric materials, in particular to a triazinyl compound, an OLED with the compound and an organic light-emitting device with the compound. The compound provided by the invention takes a triazine structure as a core, and an aryl group and an alkyl group form fixed substitution collocation on a side chain to be combined with a fluorenyl group, so that the compound has excellent luminous efficiency and relatively good thermal stability; meanwhile, when the triazinyl compound provided by the invention acts on a device, the organic light-emitting device can effectively have lower driving voltage and maintain the stability of the voltage, the light-emitting efficiency is improved, and the working life is obviously prolonged.

Description

Technical Field

[0001] This invention relates to the field of organic optoelectronic material preparation technology, specifically to a triazine compound, an OLED having the compound, and an organic light-emitting device. Background Technology

[0002] Organic light-emitting diodes (OLEDs), also known as organic light-emitting devices, typically include a cathode, anode, light-emitting layer, electron transport layer, and other organic functional material layers. By applying a voltage to the OLED, holes are injected from the anode and electrons from the cathode into the light-emitting layer. The injected holes and electrons then recombine to form excitons, causing light emission. This technique converts electrical energy into light energy through organic light-emitting materials.

[0003] Because the migration rates of hole carriers and electron carriers in most materials are mismatched, the two types of carriers are unlikely to recombine in the light-emitting layer. This leads to a decrease in the device's photoelectric performance, increased leakage current, heat generation, and reduced device lifespan. A common solution is to add a hole-blocking material layer to prevent holes from reaching the electron transport layer.

[0004] However, the existing hole-blocking materials used in devices do not perform well. They are only average in terms of luminous efficiency and lifespan. Even with different combinations of various materials, the display technology still suffers from low luminous efficiency, which seriously affects the further practical application of the technology.

[0005] Therefore, continuous efforts are needed to develop organic light-emitting devices with low voltage drive, high brightness and long lifespan, and to find suitable OLED optoelectronic functional materials for OLED devices to solve the above problems. Summary of the Invention

[0006] To address the aforementioned technical problems, this invention provides a triazine-based compound, an OLED having the compound, and a display or lighting device. The provided triarylamine compound has a triazine structure as its core, with aryl and alkyl groups combined with fluorenyl groups forming side chains. When used in organic electroluminescent devices, the triazine-based compound of this invention enables the device to simultaneously possess high efficiency and a long operating life.

[0007] This invention is achieved through the following technical solution: This invention provides a triazine-based compound having the structure shown in Formula I: ; In Formula I, R1 and R2 are each selected from hydrogen, deuterium, C1-C24 alkyl, and C6-C30 aryl, either the same or different; R3 is independently selected from hydrogen, deuterium, C1-C24 alkyl, and C6-C30 aryl; L1 is independently selected from single bond and C6-C30 arylene; Ar1 ​​and Ar2 are each independently selected from cyano-substituted or unsubstituted C6-C30 aryl; the hydrogen atoms in the structure shown in Formula I may be partially or completely deuterated.

[0008] Preferably, in Formula I, R1 and R2 are each selected from hydrogen, deuterium, methyl, ethyl, propyl, butyl, and phenyl, either the same or different.

[0009] More preferably, in Formula I, R1 and R2 are not simultaneously selected from phenyl.

[0010] Preferably, in Formula I, R3 is independently selected from hydrogen, deuterium, methyl, ethyl, propyl, butyl, or phenyl.

[0011] Preferably, in Formula I, L1 is independently selected from single bond, phenyl, naphthyl, and biphenyl.

[0012] Preferably, in Formula I, Ar1 and Ar2 are each independently selected from the following groups that are cyano-substituted or unsubstituted: phenyl, biphenyl, naphthyl.

[0013] Preferably, formula I is selected from the structure of formula A or formula B: ; The substitution of R1, R2, L1, Ar1, and Ar2 is the same as defined above.

[0014] Preferably, Formula I is selected from the structure of Formula 1 or Formula 2: ; The substitution of R3, L1, Ar1, and Ar2 is the same as defined above.

[0015] More preferably, formula I has any structure of formula A-1, A-2, B-1, or B-2: ; The substitution of L1, Ar1, and Ar2 is the same as defined above.

[0016] According to one or more embodiments, the present invention provides a triazine-based compound selected from any of the following chemical structures, where CN represents a cyano group: .

[0017] The present invention also provides the application of the triazine compound described above in the preparation of organic electroluminescent devices.

[0018] The present invention also provides an organic electroluminescent device, the organic electroluminescent device comprising: Substrate layer; A first electrode is located on the substrate; An organic light-emitting functional layer is disposed on the first electrode; The second electrode is located on the organic light-emitting functional layer; The organic light-emitting functional layer includes a triazine-based compound as shown in Formula I above.

[0019] Preferably, at least one of the organic light-emitting functional layers is an electron transport layer or a hole blocking layer, and the electron transport layer or hole blocking layer includes a triazine compound as shown in Formula I above.

[0020] The present invention also provides a composition comprising a triazine compound as described in Formula I.

[0021] The present invention also provides a formulation comprising a triazine compound with the structure shown in Formula I above, or a composition as described above, and at least one solvent. The solvent is not particularly limited and may be any solvent well known to those skilled in the art, such as unsaturated hydrocarbon solvents like toluene, xylene, mesitylene, tetrahydronaphthalene, decahydronaphthalene, dicyclohexane, n-butylbenzene, sec-butylbenzene, tert-butylbenzene, carbon tetrachloride, chloroform, dichloromethane, dichloroethane, chlorobutane, bromobutane, chloropentane, bromopentane, chlorohexane, bromohexane, chlorocyclohexane, bromocyclohexane, etc.; halogenated unsaturated hydrocarbon solvents like chlorobenzene, dichlorobenzene, trichlorobenzene, etc.; ether solvents like tetrahydrofuran, tetrahydropyran, etc.; and ester solvents like alkyl benzoates.

[0022] The organic electroluminescent device of the present invention can be used in OLED lighting or display devices.

[0023] The present invention also provides a display or lighting device comprising one or more of the organic electroluminescent devices described above.

[0024] In summary, compared with the prior art, the present invention has the following beneficial effects: The triazine compound of the present invention has a core segment of fluorenyl group co-substituted with aryl and alkyl groups on one side chain, thereby giving the compound excellent luminous efficiency and good lifespan. At the same time, the triazine compound provided by the present invention can effectively enable organic light-emitting devices to have lower driving voltage and maintain voltage stability, while improving luminous efficiency and achieving better device lifespan. Detailed Implementation

[0025] The technical solutions of the embodiments of the present invention will be clearly and completely described below. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the protection scope of the present invention.

[0026] The aryl group referred to in this invention refers to the general term for a monovalent group remaining after removing a hydrogen atom from the aromatic carbon atom of an aromatic hydrocarbon molecule. It can be a monocyclic aryl or a fused-ring aryl. The aryl group can be an aryl group having 6 to 30 carbon atoms, preferably an aryl group having 6 to 20 carbon atoms, and more preferably an aryl group having 6 to 12 carbon atoms. Examples may include phenyl, biphenyl, terphenyl, triphenylene, tetraphenylene, naphthyl, anthracene, phenanthryl, or pyrene, but are not limited thereto. Aryl or aromatic group – as used herein, considers both non-fused and fused systems. The aryl group can be an aryl group having 6 to 30 carbon atoms, preferably an aryl group having 6 to 20 carbon atoms, and more preferably an aryl group having 6 to 12 carbon atoms. Examples of aryl groups include phenyl, biphenyl, terphenyl, triphenylene, tetraphenylene, naphthalene, anthracene, fen, fluorene, pyrene, perylene, and azulene, with phenyl, biphenyl, terphenyl, triphenylene, fluorene, and naphthalene being preferred. Examples of non-fused aryl groups include phenyl, biphenyl-2-yl, biphenyl-3-yl, biphenyl-4-yl, p-terphenyl-4-yl, p-terphenyl-3-yl, p-terphenyl-2-yl, m-terphenyl-4-yl, m-terphenyl-3-yl, m-terphenyl-2-yl, o-tolyl, m-tolyl, p-tolyl, p-(2-phenylpropyl)phenyl, 4'-methylbiphenyl, 4”-tert-butyl-p-terphenyl-4-yl, o-cumyl, m-cumyl, p-cumyl, 2,3-dimethylyl, 3,4-dimethylyl, 2,5-dimethylyl, mestriylyl, and m-tetraphenyl.

[0027] The alkyl groups described in this invention include straight-chain and branched alkyl groups. They can be alkyl groups having 1 to 24 carbon atoms, with preferred alkyl groups containing 1 to 4 carbon atoms, including methyl, ethyl, propyl, 1-methylethyl, butyl, 1-methylpropyl, 2-methylpropyl, etc. Furthermore, the alkyl groups may optionally be substituted.

[0028] Throughout this specification, unless explicitly stated otherwise, the term "including" any component will be understood to imply the inclusion of other components, not to exclude any other components. Furthermore, it should be understood that throughout this specification, when an element such as a layer, film, region, or substrate is referred to as being "on" or "above" another element, it may be "directly on" the other element, or there may be intermediate elements present. Additionally, "on" or "above" means located above the target portion, and not necessarily above it in the direction of gravity.

[0029] One object of the present invention is to provide an electroluminescent device, the organic electroluminescent device comprising: a substrate layer; a first electrode on the substrate; an organic light-emitting functional layer on the first electrode; and a second electrode on the organic light-emitting functional layer; wherein the organic light-emitting functional layer comprises a hole blocking layer and an electron transport layer. In one embodiment of the present invention, the hole blocking layer or the electron transport layer in the organic electroluminescent (OLED) device comprises one or more compounds as shown in the above general formula I.

[0030] In a preferred embodiment of the present invention, an OLED is provided, comprising a substrate, an anode, a cathode, and an organic light-emitting functional layer. The organic light-emitting functional layer may include a light-emitting layer, a light-emitting auxiliary layer, a hole transport layer, a hole injection layer, a hole blocking layer, an electron transport layer, an electron injection layer, etc., or may only include a light-emitting layer and one or more other layers. The hole blocking layer or electron transport layer may contain one or more components of the compounds represented by the above general formula I. Optionally, the organic light-emitting device further includes a capping layer, a protective layer, and / or an encapsulation layer.

[0031] The substrate described in this invention can be any substrate typically used in organic light-emitting devices. It can be a glass or transparent plastic substrate, an opaque material such as silicon or stainless steel, or a flexible PI film. Different substrates have different mechanical strengths, thermal stability, transparency, surface smoothness, and water resistance, and their applications vary depending on their properties.

[0032] As for the materials used in the hole injection layer, hole transport layer, electron injection layer, and light-emitting layer, any material can be selected from known materials used in OLED devices.

[0033] The present invention will now be described in detail with reference to specific embodiments. Unless otherwise specified, all raw materials and solvents used in the synthesis embodiments are commercially available. The solvents were used directly without further processing. All intermediates used below were custom-purchased from Shanghai Beixin Technology Development Co., Ltd. .

[0034] Example Example 1: Synthesis of Compound 1 Synthesis route:

[0035] Synthesis method: Add 10 mmol of SM1, 10 mmol of MO-1, and 10 mL of dioxane solution (dioxane:water mass ratio 4:1) to a 50 mL reaction flask and mix. Reflux for 24 hours. Cool to room temperature, then slowly add saturated MgSO4 aqueous solution and ethyl acetate to the solution for extraction three times. Remove the solvent from the organic layer using a rotary evaporator, and then obtain compound 1 by column chromatography.

[0036] The structure of target product compound 1 was tested: the theoretical value was 681.31 and the measured value was 681.77 by liquid chromatography-mass spectrometry (LC-MS).

[0037] Example 2: Synthesis of Compound 8 Following the synthesis steps and reaction conditions of Example 1, compound 8 was synthesized. The difference from Example 1 is that M0-1 was replaced with M1-2, and SM1 was replaced with... The theoretical value was 793.35 and the measured value was 793.79, obtained by liquid chromatography-mass spectrometry (LC-MS).

[0038] Example 3: Synthesis of Compound 12 Following the synthesis steps and reaction conditions of Example 1, compound 12 was synthesized. The difference from Example 1 is that SM1 was replaced with... The theoretical value was 782.34 and the measured value was 782.76, obtained by liquid chromatography-mass spectrometry (LC-MS).

[0039] Example 4: Synthesis of Compound 24 Following the synthesis steps and reaction conditions of Example 1, compound 24 was synthesized. The difference from Example 1 is that MO-1 was replaced with MO-2, and SM1 was replaced with... The theoretical value was 731.33 and the measured value was 731.87, obtained by liquid chromatography-mass spectrometry (LC-MS).

[0040] Example 5: Synthesis of Compound 31 Following the synthesis steps and reaction conditions of Example 1, compound 31 was synthesized. The difference from Example 1 is that SM1 was replaced with... The theoretical value was 757.35 and the measured value was 757.81, obtained by liquid chromatography-mass spectrometry (LC-MS).

[0041] Example 6: Synthesis of Compound 33 Following the synthesis steps and reaction conditions of Example 1, compound 33 was synthesized. The difference from Example 1 is that SM1 was replaced with... The theoretical value was 909.41 and the measured value was 909.97, obtained by liquid chromatography-mass spectrometry (LC-MS).

[0042] Example 7: Synthesis of Compound 37 Following the synthesis steps and reaction conditions of Example 1, compound 37 was synthesized. The difference from Example 1 is that MO-1 was replaced with MO-3. The LC-MS (m / z) analysis by liquid chromatography-mass spectrometry yielded a theoretical value of 681.31 and a measured value of 681.79.

[0043] Example 8: Synthesis of Compound 41 Following the synthesis steps and reaction conditions of Example 1, compound 41 was synthesized. The difference from Example 1 is that MO-1 was replaced with MO-3, and SM1 was replaced with... The theoretical value was 781.35 and the measured value was 781.87, obtained by liquid chromatography-mass spectrometry (LC-MS).

[0044] Example 9: Synthesis of Compound 50 Following the synthesis steps and reaction conditions of Example 1, compound 50 was synthesized. The difference from Example 1 is that SM1 was replaced with... The theoretical value was 833.38 and the measured value was 833.96, obtained by liquid chromatography-mass spectrometry (LC-MS).

[0045] Example 10: Synthesis of Compound 55 Following the synthesis steps and reaction conditions of Example 1, compound 55 was synthesized. The difference from Example 1 is that M0-1 was replaced with M1-1. The LC-MS (m / z) analysis by liquid chromatography-mass spectrometry yielded a theoretical value of 743.33 and a measured value of 743.79.

[0046] Example 11: Synthesis of Compound 63 Following the synthesis steps and reaction conditions of Example 1, compound 63 was synthesized. The difference from Example 1 is that SM1 was replaced with... Analysis by liquid chromatography-mass spectrometry yielded the following LC-MS (m / z) values: theoretical value 833.38, measured value 833.92.

[0047] Example 12: Synthesis of Compound 71 Synthesis route:

[0048] Synthesis method: Add 10 mmol of SM1, 10 mmol of M2-1, and 10 mL of dioxane solution (dioxane:water mass ratio 4:1) to a 50 mL reaction flask and mix. Reflux for 24 hours. Cool to room temperature, then slowly add saturated MgSO4 aqueous solution and ethyl acetate to the solution for extraction three times. Remove the solvent from the organic layer using a rotary evaporator, and then obtain compound 71 by column chromatography.

[0049] The structure of the target product compound 71 was tested: the theoretical value was 743.33 and the measured value was 743.81 by liquid chromatography-mass spectrometry (LC-MS).

[0050] Example 13: Synthesis of Compound 78 Following the synthesis steps and reaction conditions of Example 12, compound 78 was synthesized. The difference from Example 12 is that M2-1 was replaced with M3, and SM1 was replaced with... Analysis by liquid chromatography-mass spectrometry yielded the following LC-MS (m / z) values: theoretical value 855.36, actual value 855.92.

[0051] Example 14: Synthesis of Compound 101 Following the synthesis steps and reaction conditions of Example 12, compound 101 was synthesized. The difference from Example 12 is that M2-1 was replaced with M2-2, and SM1 was replaced with... The theoretical value was 819.36 and the measured value was 819.94, obtained by liquid chromatography-mass spectrometry (LC-MS).

[0052] The following are several examples of applications of the triazine compounds described in this invention in OLED devices to further illustrate the beneficial effects of the compounds of this invention. The materials used in the examples were either commercially available or synthesized in-house.

[0053] Manufacturing of OLED devices: As a reference fabrication method for one embodiment of the device, the present invention involves depositing a 50-500 nm layer of ITO / Ag / ITO (ITO / Ag / ITO weight ratio of 1:(10-20):1) as the anode on an alkali-free glass substrate. On the anode, a hole injection layer (5-20 nm), a hole transport layer (50-150 nm), a light-emitting auxiliary layer (5-120 nm), a light-emitting layer (20-50 nm), a hole blocking layer (5-20 nm), an electron transport layer (20-80 nm), and an electron injection layer (0.5-10 nm) are sequentially deposited. Then, Mg and Ag (weight ratio 1:9, 10-50 nm) are co-deposited to form a semi-transparent cathode, followed by the deposition of a capping compound (30-90 nm). Finally, the light-emitting device is encapsulated using epoxy resin adhesive under a nitrogen atmosphere.

[0054] In a preferred embodiment, the OLED device provided by the present invention has the following structure: first, an alkali-free glass substrate is washed with isopropanol for 15 minutes using an ultrasonic cleaner, and then subjected to UV ozone washing treatment in the air for 30 minutes. The prepared substrate was deposited using a vacuum evaporation method. First, an ITO / Ag / ITO layer (ITO / Ag / ITO weight ratio of 1:10:1, 100nm) was deposited as the anode. Then, a hole injection layer (HT:PD weight ratio of 97:3, 10nm), a hole transport layer (HT, 135nm), a light-emitting auxiliary layer (BP, 5nm), a blue light-emitting layer (compound BH:compound BD weight ratio of 98:2, 20nm), a hole blocking layer (compound 1, 5nm), an electron transport layer (compound ET: Liq = 1:1, 30nm), and an electron injection layer (Yb, 10nm) were deposited sequentially. Mg and Ag (weight ratio of 1:9, 14nm) were then co-deposited to form a semi-transparent cathode. Finally, compound CPL (70nm) was deposited as a capping layer. The light-emitting device was then encapsulated using epoxy resin adhesive under a nitrogen atmosphere, as described in Application Example 1. The molecular structural formulas of the relevant materials are shown below (particularly preferably selected from the following structures, but this does not mean that the invention is limited to the following structures): .

[0055] Application Examples 2-14 and Comparative Example 1 were prepared using the method described in Application Example 1 above, with the only difference being that compounds listed in Table 1 were used as hole-blocking materials instead of compound 1 in Application Example 1. The structure of Ref-1 used in the Comparative Example is as follows: .

[0056] Performance evaluation of OLED devices: The current of the OLED device at different voltages was measured using a Keithley 2365A digital nanovoltmeter, and then the current density of the OLED device at different voltages was obtained by dividing the current by the emitting area. The brightness and radiant energy flux density of the OLED device at different voltages were measured using a Konicaminolta CS-2000 spectroradiometer. Based on the current density and brightness of the OLED device at different voltages, the current density (10 mA / cm²) at the same voltage was obtained. 2 The operating voltage (Volt) and current efficiency (cd / A) are given by BI = E / CIEy, which refers to the Blue Index in blue light and is also a parameter measuring the luminous efficiency of blue light. E refers to the current efficiency, and CIEy refers to the ordinate color point obtained by substituting the wavelength of the device's emission half-peak into the CIE1930 software. The test data are shown in Table 1.

[0057] Table 1. Examples of hole-blocking materials, their applications, and electron luminescence properties.

[0058] As shown in Table 1, compared with Comparative Example 1, Application Examples 1 to 14 exhibit lower operating voltage, higher BI luminous efficiency, and longer lifespan. The performance improvement in each application example is based on the fact that the triazine group of the present invention forms a specific substitution on the fluorene group with a phenyl group and an alkyl group on one side, thereby improving the luminous efficiency of the device, achieving better balance in electron and hole transport and exciton conversion efficiency, and reducing the power consumption of the device.

[0059] This specific embodiment is merely an explanation of the present invention and is not intended to limit the invention. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they are within the scope of the claims of the present invention.

Claims

1. A triazine-based compound, characterized in that, It has the structure shown in Equation I: ； In Formula I, R1 and R2 are each selected from hydrogen, deuterium, C1-C24 alkyl, and C6-C30 aryl, either the same or different; R3 is independently selected from hydrogen, deuterium, C1-C24 alkyl, and C6-C30 aryl; L1 is independently selected from single bond and C6-C30 arylene; Ar1 ​​and Ar2 are each independently selected from cyano-substituted or unsubstituted C6-C30 aryl; the hydrogen atoms in the structure shown in Formula I may be partially or completely deuterated.

2. The triazine compound according to claim 1, characterized in that, In Formula I, R1 and R2 are each selected from hydrogen, deuterium, methyl, ethyl, propyl, butyl, and phenyl, either the same or different; R3 is independently selected from hydrogen, deuterium, methyl, ethyl, propyl, butyl, or phenyl; L1 is independently selected from single bond, phenyl, naphthyl, and biphenyl; Ar1 ​​and Ar2 are each independently selected from the following groups that are cyano-substituted or unsubstituted: phenyl, biphenyl, and naphthyl.

3. The triazine compound according to claim 1, characterized in that, Formula I is selected from either Formula A or Formula B: ； The substitutions of R1, R2, L1, Ar1, and Ar2 are as defined in claim 1.

4. The triazine compound according to claim 1, characterized in that, Formula I is selected from the structure of Formula 1 or Formula 2: ； The substitutions of R3, L1, Ar1, and Ar2 are as defined in claim 1.

5. The triazine compound according to claim 1, characterized in that, Equation I is represented by any structure of Equation A-1, A-2, B-1, or B-2: ； The substitutions of L1, Ar1, and Ar2 are as defined in claim 1.

6. The triazine compound according to claim 1, characterized in that, Choose any one of the chemical structures shown below, where CN represents cyano: 。 7. A composition, characterized in that, The composition comprises a triazine compound as described in any one of claims 1-6.

8. A formulation, characterized in that, The formulation comprises a triazine compound as described in any one of claims 1-6 and at least one solvent.

9. The use of the triazine compound according to any one of claims 1-6 in the preparation of organic electroluminescent devices.

10. An organic electroluminescent device, characterized in that, The organic electroluminescent device includes: Substrate layer; A first electrode is located on the substrate; An organic light-emitting functional layer is disposed on the first electrode; The second electrode is located on the organic light-emitting functional layer; The organic light-emitting functional layer includes a triazine compound as described in any one of claims 1-6.

11. The organic electroluminescent device according to claim 10, characterized in that, At least one of the organic light-emitting functional layers is an electron transport layer or a hole blocking layer, and the electron transport layer or hole blocking layer includes a triazine compound as described in any one of claims 1-6.

12. A display or lighting device, characterized in that, The device includes an organic electroluminescent device as described in any one of claims 10-11.

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