Triazine compound, organic electroluminescent device and display device

Abstract

The invention provides a triazine compound, an organic electroluminescent device and a display device, and relates to the technical field of organic photoelectric display. By designing the structure of the compound, the obtained triazine compound has excellent performance, and the organic electroluminescent device prepared by taking the triazine compound as a luminescent layer main body material has relatively low driving voltage and relatively high current efficiency.

Description

Technical Field

[0001] This invention belongs to the field of organic optoelectronic display technology, specifically relating to a triazine compound, an organic electroluminescent device, and a display device. Background Technology

[0002] Organic light emitting diodes (OLEDs) are display components that utilize self-emissive properties. They have a wider viewing angle and are thinner, lighter, and faster than liquid crystal displays. They can also achieve flexible displays, making them highly anticipated for use as full-color display components or lighting equipment.

[0003] Organic light emission typically refers to the phenomenon of converting electrical energy into light energy using organic materials. Organic light-emitting devices that utilize organic light emission usually have a structure that includes an anode, a cathode, and an organic layer sandwiched between the anode and the cathode.

[0004] In organic light-emitting elements (OLEDs), the organic layer is often composed of multiple functional layers made of different materials to improve efficiency and stability. For example, it may consist of a hole injection layer, a hole transport layer, a light-emitting layer, an electron transport layer, and an electron injection layer. When a voltage is applied between the two electrodes in this OLED structure, holes from the anode are injected into the organic layer, and electrons from the cathode are also injected into the organic layer. When the injected holes and electrons meet, they form excitons. When these excitons release energy and transition to the ground state, they emit photons, thus producing light. OLEDs are widely recognized for their self-emissive nature, high brightness, high efficiency, low driving voltage, wide viewing angle, high contrast, and high-speed response.

[0005] Currently, research on organic electroluminescent materials has been widely carried out in academia and industry. Among these, the material's transport properties and luminous efficiency restrict the industrialization of light-emitting devices. Therefore, designing and searching for a compound as a novel OLED material to overcome its shortcomings in practical applications is a key focus and future research trend in OLED materials research. Summary of the Invention

[0006] To address the shortcomings of existing technologies, the present invention aims to provide a triazine compound, an organic electroluminescent device, and a display device.

[0007] To achieve this objective, the present invention adopts the following technical solution:

[0008] In a first aspect, the present invention provides a triazine compound having the structure shown in Formula I:

[0009]

[0010] Formula I;

[0011] Ar1 is selected from substituted or unsubstituted triphenylsilyl groups, substituted or unsubstituted C6~C6 groups. 30 aryl, substituted or unsubstituted C3~C 30 Mixed aromatics;

[0012] When the substituted or unsubstituted group contains a substituent, each substituent is independently selected from deuterium, F, cyano, C1~C1. 12 Alkyl, C6~C 30 Aryl or C3~C 30 Mixed aromatics;

[0013] Furthermore, the hydrogen atoms in Formula I can be independently replaced by deuterium, F, cyano, C1~C 12 Alkyl, C6~C 30 Aryl or C3~C 30 It is replaced by heteroaryl compounds.

[0014] Preferably, the C1-C12 alkyl group is selected from methyl, ethyl, n-propyl, isopropyl, n-butyl, tert-butyl, n-pentyl, tert-pentyl, n-hexyl or cyclohexyl; more preferably, the C1-C12 alkyl group is selected from methyl, ethyl, isopropyl or tert-butyl.

[0015] Preferably, the C6-C30 aryl group is selected from phenyl, biphenyl, terphenyl, naphthyl, anthracene, indene, fluorenyl, perylene, phenanthrene, pyrene, fluoranyl, spirodifluorenyl, or benzophenanthrene; more preferably, the C6-C30 aryl group is selected from phenyl, biphenyl, or naphthyl.

[0016] Preferably, the C3-C30 heteroaryl group is selected from pyridyl, benzofuranyl, benzothiophenyl, dibenzofuranyl, dibenzothiophenyl, carbazoleyl, diaryleneamine, benzofuranocarbazoleyl, benzofuranothiophenyl, triazineyl, etc. , or , * represents a connection site.

[0017] Preferably, in Ar1, C6~C 30 The aryl group is selected from phenyl, biphenyl, or naphthyl.

[0018] Preferably, in Ar1, C3~C 30 The heteroaryl group is selected from carbazole, dibenzofuran, pyridyl, , or , * represents a connection site.

[0019] Preferably, when the substituted or unsubstituted group contains a substituent, the substituent is independently selected from deuterium or carbazole.

[0020] Preferably, the hydrogen atoms in Formula I can be independently replaced by deuterium or phenyl.

[0021] Preferably, the triazine compound has the structure shown in Formula I-1 to Formula I-2:

[0022] ;

[0023] In Equations I-1 to I-2, Ar1 has the same defined range as in Equation I;

[0024] The hydrogen atoms in Formulas I-1 to I-2 can be independently replaced by deuterium, F, cyano, C1 to C2. 12 Alkyl, C6~C 30 Aryl or C3~C 30 It is replaced by heteroaryl compounds.

[0025] Preferably, the hydrogen atoms in Formula I-1 to Formula I-2 can be independently replaced by deuterium or phenyl.

[0026] Preferably, the triazine compound is selected from any one of compounds 1 to 42:

[0027] .

[0028] This invention lists some specific structural forms of the triazine compounds, but the triazine compounds described in this invention are not limited to these listed chemical structures. Any structure based on the structure shown in Formula I, where Ar1 satisfies the above-mentioned limiting conditions, should be included.

[0029] In a second aspect, the present invention provides an organic electroluminescent device comprising a triazine compound as described in the first aspect.

[0030] Preferably, the organic electroluminescent device includes a first electrode, a second electrode, and an organic layer disposed between the first electrode and the second electrode; the organic layer includes a light-emitting layer; the light-emitting layer includes the aforementioned triazine compound.

[0031] Preferably, the light-emitting layer comprises a host material, which includes the aforementioned triazine compound.

[0032] Preferably, the light-emitting layer further includes a dopant material.

[0033] Preferably, in the light-emitting layer, the volume percentage of the triazine compound is 60% to 99.9% (for example, it can be 60%, 65%, 70%, 75%, 80%, 85%, 90%, 95%, 98%, or 99.9%).

[0034] Preferably, in the light-emitting layer, the volume percentage of the dopant material is 0.1% to 40% (e.g., 0.1%, 2%, 5%, 10%, 15%, 20%, 25%, 30%, 35%, 40%). This invention does not impose any special restrictions on the specific selection of the dopant material for the light-emitting layer; commonly used dopant materials in the art are applicable.

[0035] Preferably, the light-emitting layer is prepared by vapor deposition.

[0036] Preferably, the organic layer further includes a hole layer, which includes at least one of a hole injection layer, a hole transport layer, and an electron blocking layer. The present invention does not impose any special restrictions on the specific material selection for the hole layer; commonly used hole layer materials in the art are applicable.

[0037] Preferably, the organic layer further includes an electronic layer, which includes at least one of an electron injection layer, an electron transport layer, and a hole blocking layer. The present invention does not impose any special restrictions on the specific material selection for the electronic layer; commonly used electronic layer materials in the art are applicable.

[0038] Thirdly, the present invention provides a display device comprising the organic electroluminescent device as described in the second aspect.

[0039] Compared with the prior art, the present invention has the following beneficial effects:

[0040] This invention designs the structure of triazine compounds, resulting in triazine compounds with excellent luminescent properties. These compounds can be used to prepare organic electroluminescent devices, especially as the main material of the light-emitting layer in organic electroluminescent devices. They can effectively reduce the driving voltage of organic electroluminescent devices and improve the current efficiency of organic electroluminescent devices. Detailed Implementation

[0041] To facilitate understanding of the present invention, the following embodiments are provided. Those skilled in the art should understand that these embodiments are merely illustrative and should not be construed as limiting the scope of the invention.

[0042] Synthesis Example 1

[0043]

[0044] Under nitrogen protection, 200 mL of dry N,N-dimethylformamide, 0.01 mol of compound 1-0, and 0.012 mol of 7H-benzo[KL]acridine were added to a 1000 mL three-necked flask. The mixture was cooled to -5 °C, and 0.055 mol of sodium hydride was slowly added. After the sodium hydride was completely added, the mixture was kept at 0 °C and stirred for 1 h. Then, the temperature was naturally raised to 25 °C and stirred for 4 h. The mixture was then cooled to 0 °C, and a saturated ammonium chloride aqueous solution was slowly added dropwise until the pH was between 6 and 8. 200 mL of water was added to the reaction solution, and the precipitated solid was filtered. The resulting filter cake was recrystallized from the mixture of toluene and ethanol to obtain compound 1. The mass-to-charge ratio (m / z) of compound 1 was measured to be 706.3 by mass spectrometry.

[0045] Synthesis Example 2

[0046] This embodiment provides a method for synthesizing compound 5, the method being as follows:

[0047]

[0048] Following the synthesis method of Synthesis Example 1, compound 5 can be obtained by replacing compound 1-0 in Synthesis Example 1 with an equimolar amount of compound 5-0, while keeping other conditions unchanged.

[0049] Mass spectrometry analysis of compound 5: The mass spectrum (m / z) was 756.3.

[0050] Synthesis Example 3

[0051] This embodiment provides a method for synthesizing compound 6, the method being as follows:

[0052]

[0053] Following the synthesis method of Synthesis Example 1, compound 6 can be obtained by replacing compound 1-0 in Synthesis Example 1 with an equimolar amount of compound 6-0, while keeping other conditions unchanged.

[0054] Mass spectrometry analysis of compound 6: The mass spectrum (m / z) was 756.3.

[0055] Synthesis Example 4

[0056] This embodiment provides a method for synthesizing compound 14, the method being as follows:

[0057] ,

[0058] Following the synthesis method of Synthesis Example 1, compound 14 can be obtained by replacing compound 1-0 in Synthesis Example 1 with an equimolar amount of compound 14-0, while keeping other conditions unchanged.

[0059] Mass spectrometry analysis of compound 14: The mass spectrum (m / z) was 795.3.

[0060] Synthesis Example 5

[0061] This embodiment provides a method for synthesizing compound 15, the method being as follows:

[0062]

[0063] Following the synthesis method of Synthesis Example 1, compound 15 can be obtained by replacing compound 1-0 in Synthesis Example 1 with an equimolar amount of compound 15-0 while keeping other conditions unchanged.

[0064] Mass spectrometry analysis of compound 15: The mass spectrum (m / z) was 795.3.

[0065] Synthesis Example 6

[0066] This embodiment provides a method for synthesizing compound 16, the method being as follows:

[0067]

[0068] Under nitrogen protection, 200 mL of dry N,N-dimethylformamide, 0.01 mol of compound 16-0, and 0.024 mol of 7H-benzo[KL]acridine were added to a 1000 mL three-necked flask. The mixture was cooled to -5 °C, and 0.055 mol of sodium hydride was slowly added. After the sodium hydride was completely added, the mixture was kept at 0 °C with stirring for 1 h, then naturally heated to 25 °C and stirred for 4 h. The mixture was then cooled to 0 °C, and a saturated ammonium chloride aqueous solution was slowly added dropwise until the pH reached 6-8. 200 mL of water was added to the reaction solution, and the precipitated solid was filtered. The resulting filter cake was recrystallized from a mixed solvent of toluene and ethanol to obtain compound 16.

[0069] Mass spectrometry analysis of compound 16 yielded a mass-to-charge ratio (m / z) of 845.3.

[0070] Synthesis Example 7

[0071] This embodiment provides a method for synthesizing compound 18, the method being as follows:

[0072]

[0073] Following the synthesis method of Synthesis Example 1, compound 18 can be obtained by replacing compound 1-0 in Synthesis Example 1 with an equimolar amount of compound 18-0 while keeping other conditions unchanged.

[0074] Mass spectrometry analysis of compound 18: The mass spectrum (m / z) was 796.3.

[0075] Synthesis Example 8

[0076] This embodiment provides a method for synthesizing compound 29, the method being as follows:

[0077]

[0078] Following the synthesis method of Synthesis Example 1, compound 29 was obtained by replacing compound 1-0 in Synthesis Example 1 with an equimolar amount of compound 29-0, while keeping other conditions unchanged.

[0079] Mass spectrometry analysis of compound 29 yielded a mass spectrum (m / z) of 964.3.

[0080] Synthesis Example 9

[0081] This embodiment provides a method for synthesizing compound 42, the method being as follows:

[0082]

[0083] 0.01 mol of compound 15 was added to a reaction flask, followed by 160 mL of deuterium benzene and 0.05 mol of trifluoromethanesulfonic anhydride. The mixture was heated to 80 °C under nitrogen protection and kept at this temperature for 24 h. After cooling to room temperature, the reaction was quenched with a saturated sodium bicarbonate aqueous solution, washed with water until neutral, dried with anhydrous magnesium sulfate, and passed through a silica gel column. The crude product was recrystallized from the crude product using a mixed solvent of toluene and ethanol to obtain compound 42.

[0084] Mass spectrometry analysis of compound 42: The mass spectrum (m / z) was 832.5.

[0085] Other compounds for which specific synthesis steps are not listed can be prepared using common knowledge in the art, in conjunction with the above examples.

[0086] The specific structures of some of the compounds used in the following device embodiments and device comparative examples are shown below:

[0087] , , , , , .

[0088] In the following device embodiments, triazine compounds provided by the present invention are selected as the main material of the light-emitting layer in the organic electroluminescent device, and the device comparative examples use the above-mentioned ETH-1, ETH-2, and ETH-3 as the main material of the light-emitting layer in the organic electroluminescent device.

[0089] Device Example 1

[0090] This embodiment of the device provides an organic electroluminescent device, using compound 1 provided in the synthesis embodiment 1 of the present invention as the main material of the light-emitting layer; and in this embodiment, the light-emitting layer is prepared by vapor deposition.

[0091] The organic electroluminescent device has the following structure:

[0092] ITO / HT (40nm) / Compound 1: D-1 5% / ET (30nm) / LiF (0.5nm) / Al (150nm).

[0093] The fabrication method of the above-mentioned organic electroluminescent device is as follows:

[0094] The glass substrate coated with an ITO transparent conductive layer (as the anode) was ultrasonically treated in a cleaning agent, then rinsed in deionized water, then ultrasonically degreased in a mixed solvent of acetone and ethanol, then baked in a clean environment until completely dehydrated, cleaned with ultraviolet light and ozone, and bombarded with a low-energy cation beam to improve the surface properties and enhance the bonding ability with the hole injection layer.

[0095] The glass substrate was placed in a vacuum chamber and evacuated to a vacuum level of 1×10⁻⁶. -5 ~9×10 -6 Pa, HT is vacuum-deposited on the anode as a hole transport layer at a deposition rate of 0.1 nm / s and a film thickness of 40 nm;

[0096] A light-emitting layer is vacuum-deposited on top of the hole transport layer at a deposition rate of 0.1 nm / s and a film thickness of 30 nm. The light-emitting layer is composed of a host material and a dopant material. The host material is compound 1 provided by this invention, and the dopant material is compound D-1. 5% refers to the doping ratio of the dopant material, that is, the volume ratio of the host material to the dopant material of the light-emitting layer is 95:5.

[0097] An electron transport layer (ET) was vacuum-deposited on top of the light-emitting layer at a rate of 0.1 nm / s and a film thickness of 30 nm.

[0098] 0.5 nm LiF and 150 nm Al were vacuum-deposited on the electron transport layer as the electron injection layer and cathode, respectively.

[0099] The brightness, driving voltage, current efficiency, and lifetime of the prepared organic electroluminescent device were measured, as detailed in Table 1.

[0100] Device Examples 2-12

[0101] Device Examples 2-12 each provide an organic electroluminescent device, which differs from Device Example 1 only in that the main material of the light-emitting layer is different (see Table 1 for details), while other conditions are the same as those in Device Example 1.

[0102] Device Comparison Examples 1-3

[0103] Comparative Examples 1 to 3 each provide an organic electroluminescent device, which differs from Device Example 1 only in that the main material of the light-emitting layer is different (see Table 1 for details), while other conditions are the same as Device Example 1.

[0104] Performance testing

[0105] The driving voltage, current efficiency, and lifetime (LT90) of the OLED devices provided above were tested. LT90 refers to the time required for the brightness to decrease to 90% of its original brightness while maintaining an initial brightness of 1000 nits at a constant current density. Test items included the brightness, driving voltage, and current efficiency of the organic light-emitting diode. The driving voltage, current efficiency, and LT90 data were all based on a brightness of 1000 cd / m². 2 The relative values ​​at different times (based on ETH-3 test data). The performance test results of the organic electroluminescent devices are shown in Table 1 below.

[0106] Table 1

[0107] Main materials <![CDATA[Required luminance / (cd / m 2 )]]> Drive voltage Current efficiency LT90 lifespan Device Comparison Example 1 ETH-1 1000 1.23 0.74 0.98 Device Comparison Example 2 ETH-2 1000 1.17 0.92 0.95 Device Comparison Example 3 ETH-3 1000 1 1 1 Device Example 1 Compound 1 1000 0.97 1.16 1.14 Device Example 2 Compound 5 1000 0.91 1.25 1.22 Device Example 3 Compound 6 1000 0.83 1.19 1.18 Device Example 4 Compound 14 1000 0.79 1.31 1.28 Device Example 5 Compound 15 1000 0.75 1.35 1.38 Device Example 6 Compound 16 1000 0.64 1.28 1.41 Device Example 7 Compound 18 1000 0.87 1.49 1.25 Device Example 8 Compound 29 1000 0.91 1.17 1.79 Device Example 9 Compound 42 1000 0.76 1.34 2.11

[0108] As can be seen from the above, the present invention, through structural design, obtains a compound suitable as the main material of the light-emitting layer. The organic electroluminescent device prepared thereby has a lower driving voltage, higher current efficiency, and longer service life.

[0109] The present invention has been illustrated with the above embodiments to describe the detailed process flow of the present invention. However, the present invention is not limited to the above detailed process flow, that is, it does not mean that the present invention must rely on the above detailed process flow to be implemented. Those skilled in the art should understand that any improvements to the present invention, equivalent substitutions of the raw materials of the product of 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 triazine compound, characterized in that, The triazine compounds have the structure shown in Formula I: Formula I; Ar1 is selected from substituted or unsubstituted triphenylsilyl groups, substituted or unsubstituted C6~C6 groups. 30 Aryl, substituted or unsubstituted C3~C 30 Mixed aromatics; When the substituted or unsubstituted group contains a substituent, each substituent is independently selected from deuterium, F, cyano, C1~C1. 12 Alkyl, C6~C 30 Aryl or C3~C 30 Mixed aromatics; Furthermore, the hydrogen atoms in Formula I can be independently converted by deuterium, F, cyano, C1~C 12 Alkyl, C6~C 30 Aryl or C3~C 30 It is replaced by heteroaryl compounds.

2. The triazine compound according to claim 1, characterized in that, In Ar1, C6~C 30 The aryl group is selected from phenyl, biphenyl, or naphthyl; Preferably, in Ar1, C3~C 30 The heteroaryl group is selected from carbazole, dibenzofuran, pyridyl, , or , * represents a connection site.

3. The triazine compound according to claim 1, characterized in that, When the substituted or unsubstituted group contains a substituent, each substituent is independently selected from deuterium or carbazole.

4. The triazine compound according to claim 1, characterized in that, In Formula I, each hydrogen atom can be independently replaced by either deuterium or phenyl.

5. The triazine compound according to claim 1, characterized in that, The triazine compounds have structures as shown in Formula I-1 to Formula I-2: ； In Equations I-1 to I-2, Ar1 has the same defined range as in Equation I; The hydrogen atoms in Formulas I-1 to I-2 can be independently replaced by deuterium, F, cyano, C1 to C2. 12 Alkyl, C6~C 30 Aryl or C3~C 30 It is replaced by heteroaryl compounds.

6. The triazine compound according to claim 1, characterized in that, The triazine compound is selected from any one of compounds 1 to 42: 。 7. An organic electroluminescent device, characterized in that, The organic electroluminescent device comprises a triazine compound as described in any one of claims 1 to 6.

8. The organic electroluminescent device according to claim 7, characterized in that, The organic electroluminescent device includes a first electrode, a second electrode, and an organic layer disposed between the first electrode and the second electrode; the organic layer includes a light-emitting layer; the light-emitting layer includes the triazine compound.

9. The organic electroluminescent device according to claim 8, characterized in that, The light-emitting layer includes a host material, which includes the aforementioned triazine compound.

10. A display device, characterized in that, The display device includes an organic electroluminescent device as described in any one of claims 7 to 9.

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