An arylamine organic compound and an organic electroluminescence device prepared by the same
By using aromatic amine organic compounds with specific structures as hole transport materials, the problems of insufficient hole injection and transport material performance were solved, carrier balance and high-temperature stability were achieved, and the efficiency and lifetime of organic electroluminescent devices were improved.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Patents(China)
- Current Assignee / Owner
- JIANGSU SUNERA TECH CO LTD
- Filing Date
- 2021-12-13
- Publication Date
- 2026-07-24
AI Technical Summary
The hole injection and transport materials in existing organic electroluminescent devices have relatively weak performance, resulting in a mismatch in carrier mobility, which affects the stability and lifespan of the devices, especially exhibiting the problem of being electron-rich and hole-deficient in high-temperature environments.
Aromatic amine organic compounds are used as hole transport materials. Through specific structural design, including the asymmetric connection and bridging groups of triarylamines, a stable film phase is formed, which improves hole mobility and thermal stability. Specific electronic materials are then used to achieve carrier balance.
It improves the efficiency and lifespan of organic electroluminescent devices, especially extending the device lifespan under high temperature conditions, and reduces the driving voltage.
Smart Images
Figure CN116262702B_ABST
Abstract
Description
Technical Field
[0001] This invention relates to the field of semiconductor materials technology, and in particular to an aromatic amine organic compound and an organic electroluminescent device prepared therefrom. Background Technology
[0002] In organic light-emitting diodes (OLEDs), charge carriers (holes and electrons) are injected into the device through two electrodes under the drive of an electric field, and recombine to emit light in the organic light-emitting layer. High-performance OLEDs require various organic functional materials to possess excellent photoelectric properties. For example, as charge transport materials, they must have good carrier mobility. The hole injection and transport characteristics of the hole injection layer and hole transport layer materials used in existing OLEDs are relatively weak, and the hole injection and transport rates are mismatched with those of electrons, resulting in a large shift in the recombination region and negatively impacting device stability. Furthermore, proper energy level matching between the hole injection layer and hole transport layer materials is crucial for improving device efficiency and lifetime. Therefore, adjusting the balance between holes and electrons and regulating the recombination region has always been an important research topic in this field.
[0003] Blue organic light-emitting diodes (OLEDs) have always been a weak point in the development of full-color OLEDs. To date, the efficiency and lifetime of blue light-emitting devices have been difficult to improve comprehensively. Therefore, improving the performance of these devices remains a crucial issue and challenge in this field. Currently, most blue light-emitting substrates used in the market are electron-biased. Therefore, to regulate the carrier balance of the emitting layer, the hole transport material needs to have excellent hole transport performance. Better hole injection and transport will cause the recombination region to shift away from the electron blocking layer, thus reducing luminescence at the interface and improving device performance and lifetime. Therefore, the hole transport region material is required to have high hole injection capacity, high hole mobility, high electron blocking capacity, and high electron weather resistance.
[0004] As is well known in the art, in high-temperature environments, the difference between electron mobility and hole mobility is more pronounced, resulting in blue light devices exhibiting electron-rich and hole-deficient characteristics and poor device lifetime. In order to improve the high-temperature lifetime of blue light devices, it is necessary to improve the mobility of hole transport materials, especially the mobility under high-temperature conditions. Summary of the Invention
[0005] To address the aforementioned problems in the prior art, the applicant of this invention provides an aromatic amine organic compound and an organic electroluminescent device prepared therefrom. The organic compound of this invention possesses excellent hole transport capability and thermal stability. When the aromatic amine organic compound of this invention is used to form the hole transport material of an organic electroluminescent device, it can simultaneously exhibit the effects of improved device efficiency and extended lifetime, especially extending the high-temperature lifetime of the device.
[0006] The technical solution of the present invention is as follows:
[0007] An aromatic amine organic compound, the structure of which is shown in general formula (1):
[0008] General formula (1)
[0009] In general formula (1), R1-R4 are independently represented by the structure shown in general formula (2), substituted or unsubstituted C6-C. 30 Aryl, substituted or unsubstituted C3-C containing one or more heteroatoms 30 One of the heteroaryl groups, and at least one of them is represented by the structure shown in general formula (2);
[0010] General formula (2)
[0011] In general formula (2), A represents any one of the structures shown in general formula (3) to general formula (6), and any one of the structures shown in general formula (3) to general formula (6) is connected to the main structure of general formula (2) by ab loop;
[0012] General formula (3) General formula (4) General formula (5) General formula (6)
[0013] In general formulas (3) to (6), "*" indicates a site that can be fused into a ring; in general formulas (3) and (5), X represents an oxygen atom or a sulfur atom.
[0014] In general formula (1), R5 and R6 are independently represented as hydrogen atom, deuterium atom, phenyl, naphthyl, biphenyl, furanyl, benzofuranyl or dibenzofuranyl, and R5 and R6 are not simultaneously hydrogen atom and deuterium atom;
[0015] The substituents used for the substituent groups are selected from one or more of the following: deuterium, methyl, ethyl, tert-butyl, adamantyl, phenyl, naphthyl, and biphenyl.
[0016] In a preferred embodiment, the structure of the compound is shown in any one of general formulas (1-1) to (1-2):
[0017] General formula (1-1) General formula (1-2)
[0018] The meanings of R1-R6 and A are the same as those defined above.
[0019] In a preferred embodiment, the structure of the compound is shown in any one of general formulas (2-1) to (2-4):
[0020] General formula (2-1) General formula (2-2)
[0021] General formula (2-3) General formula (2-4)
[0022] The meanings of R1-R6 and A are the same as those defined above.
[0023] In a preferred embodiment, the structure of the compound is shown in any one of general formulas (3-1) to (3-8):
[0024] General formula (3-1) General formula (3-2)
[0025] General formula (3-3) General formula (3-4) General formula (3-5) General formula (3-6)
[0026] General formula (3-7) General formula (3-8)
[0027] The meanings of R1-R6 and X are the same as those defined above.
[0028] In a preferred embodiment, the structure of the compound is shown in any one of general formulas (4-1) to (4-4):
[0029] General formula (4-1) General formula (4-2)
[0030] General formula (4-3) General formula (4-4)
[0031] General formula (4-5) General formula (4-6)
[0032] R1, R2, R3, and R4 are each independently represented as one of the following: substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted diphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted thienyl, substituted or unsubstituted benzothienyl, substituted or unsubstituted dibenzothienyl, substituted or unsubstituted furanyl, substituted or unsubstituted benzofuranyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted phenanthyl, substituted or unsubstituted indole, and substituted or unsubstituted piperonyl.
[0033] X represents an oxygen atom or a sulfur atom;
[0034] R5 and R6 are each independently represented as one of phenyl, naphthyl, and biphenyl;
[0035] The substituents used for the substituent groups are selected from one or more of the following: deuterium, methyl, ethyl, tert-butyl, adamantyl, phenyl, naphthyl, and biphenyl.
[0036] In a preferred embodiment, R1-R4 are each independently represented as one of the following: substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted diphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted thiophene, substituted or unsubstituted benzothiophene, substituted or unsubstituted dibenzothiophene, substituted or unsubstituted furanyl, substituted or unsubstituted benzofuranyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted phenanthyl, substituted or unsubstituted indole, and substituted or unsubstituted piperonyl.
[0037] R5 and R6 are each independently represented by one of hydrogen atom, phenyl, naphthyl, and biphenyl, and R5 and R6 do not simultaneously represent hydrogen atom; the substituents used for the substituent groups are selected from one or more of deuterium atom, methyl, ethyl, tert-butyl, adamantyl, phenyl, naphthyl, and biphenyl.
[0038] More preferably, the specific structure of the compound is any one of the following structures:
[0039] (1) (2) (3)
[0040] (4) (5) (6)
[0041] (7) (8) (9)
[0042] (10) （11） （12）
[0043] （13） （14） （15）
[0044] （16） （17） （18）
[0045] （19） （20） （21）
[0046] （22） （23） （24）
[0047] （25） （26） （27）
[0048] （28） （29） （30）
[0049] （31） （32） （33）
[0050] （34） （35） （36）
[0051] （37） （38） （39）
[0052] （40） （41） （42）
[0053] （43） （44） （45）
[0054] （46） （47） （48）
[0055] （49） （50） （51）
[0056] （52） （53） （54）
[0057] （55） （56） （57）
[0058] （58） （59） （60）
[0059] （61） （62） （63）
[0060] （64） （65） （66）
[0061] （67） （68） （69）
[0062] （70） （71） （72）
[0063] （73） （74） （75）
[0064] （76） （77） （78）
[0065] （79） （80） （81）
[0066] （82） （83） （84）
[0067] （85） （86） （87）
[0068] （88） （89） （90）
[0069] （91） （92） （93）
[0070] （94） （95） （96）
[0071] （97） （98） （99）
[0072] （100） （101） （102）
[0073] （103） （104） （105）
[0074] （106） （107） （108）
[0075] （109） （110） （111）
[0076] （112） （113） （114）
[0077] （115） （116） （117）
[0078] （118） （119） （120）
[0079] （121） （122） （123）
[0080] （124） （125） （126）
[0081] （127） （128） （129）
[0082] （130） （131） （132）
[0083] （133） （134） （135）
[0084] （136） （137） （138）
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[0087] （145） （146） （147）
[0088] （148） （149） （150）
[0089] （151） （152） （153）
[0090] （154） （155） （156）
[0091] （157） （158） （159）
[0092] （160） （161） （162）
[0093] （163） （164） （165）
[0094] （166） （167） （168）
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[0097] （175） （176） （177）
[0098] （178） （179） （180）
[0099] （181） （182） （183）
[0100] （184） （185） （186）
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[0113] （223） （224） （225）
[0114] （226） （227） （228）
[0115] （229） （230） （231）
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[0154] （345） （346） （347）
[0155] （348） （349） （350）
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[0198] （477） （478） （479）
[0199] （480） （481） （482）
[0200] （483） （484） （485）
[0201] （486） （487） （488）
[0202] （489） （490） （491）
[0203] （492） （493） （494）
[0204] （495） （496） （497）
[0205] （498） （499） (500)
[0206] (501) (502) (503)
[0207] (504) (505) (506)
[0208] (507) (508) (509)
[0209] (510) (511) (512)
[0210] (513) (514) (515)
[0211] (516).
[0212] An organic electroluminescent device comprises, in sequence, an anode, a hole transport region, a light-emitting region, an electron transport region, and a cathode, wherein the hole transport region contains the aforementioned aromatic amine organic compound.
[0213] In a preferred embodiment, the hole transport region includes a hole injection layer, a hole transport layer, and an electron blocking layer, wherein the hole transport layer and the hole injection layer contain the aforementioned aromatic amine organic compound.
[0214] In a preferred embodiment, the hole transport layer comprises the aforementioned aromatic amine organic compound, and the hole injection layer is composed of the aforementioned aromatic amine organic compound and other P-type doped materials used for the hole injection layer.
[0215] In a preferred embodiment, the electron transport region comprises a nitrogen heterocyclic compound represented by general formula (7):
[0216] General formula (7)
[0217] Ar1, Ar2, and Ar3 are independently selected from substituted or unsubstituted C6-C. 30 Aryl, substituted or unsubstituted C3-C containing one or more heteroatoms 30 One of the heteroaryl groups;
[0218] L1 represents C6-C with a single bond, substitution, or no substitution. 30aryl, substituted or unsubstituted C3-C containing one or more heteroatoms 30 One of the heteroaryl groups;
[0219] X1, X2, and X3 independently represent N or CH, and at least one of X1, X2, and X3 represents N;
[0220] Each heteroatom is independently selected from N, O, or S;
[0221] The substituents used for the substituent groups are one or more of the following: deuterium atom, phenyl, naphthyl, biphenyl, dibenzofuranyl, dibenzothiophenyl, pyridyl, and pyrimidinyl.
[0222] In a preferred embodiment, Ar1, Ar2, and Ar3 are independently represented as one of the following: substituted or unsubstituted phenyl, substituted or unsubstituted biphenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted pyridyl, substituted or unsubstituted pyrimidinyl, substituted or unsubstituted dibenzothiophene, or substituted or unsubstituted quinolinyl.
[0223] L1 is represented as a single bond, phenylene, biphenylene, or naphthylene;
[0224] The substituents used for the substituent groups are one or two of the following: deuterium, phenyl, naphthyl, biphenyl, dibenzofuranyl, dibenzothiophenyl, pyridyl, and pyrimidinyl.
[0225] The beneficial technical effects of this invention are as follows:
[0226] The core technology of this invention lies in the fact that the two triarylamines of the aromatic amine organic compound are connected in the para position, one of the arylamines has a branched spirocyclic derivative, and the bridging group in the middle must have an aryl group as a substituent. This conformation gives the molecule with the characteristics of this invention the following advantages.
[0227] (1) The structure of the aromatic amine organic compounds is asymmetric. This asymmetric structure is beneficial for the molecules to maintain a stable amorphous film phase when forming a film, thereby ensuring the physicochemical stability of the film phase and the stability of the film phase under the action of point formation, which in turn is beneficial to obtaining the lifetime stability of the device.
[0228] (2) Due to the asymmetry of the intermediate bridging group in the structure of aromatic amine organic compounds, it is ensured that energy levels with different carrier conduction are formed in the molecular structure, thereby forming different carrier conduction channels. This is beneficial to carrier injection and conduction between materials with different energy levels, and thus beneficial to obtaining the interface stability between the aromatic amine material and the adjacent material, thereby beneficial to obtaining good high and low temperature driving life of the application device.
[0229] (3) We know that for hole-carrier conductive materials, the more widely HOMO is distributed on the molecule, the higher the proportion of segments on the molecule involved in HOMO conduction, and thus the easier it is to obtain higher hole carrier conduction efficiency. Based on the in-depth research of the inventors, the stereobridging group characterized by the present invention is more conducive to the distribution of HOMO on the entire molecule, thereby making it easier to obtain high carrier mobility of the material, and thus easier to obtain low voltage driving effect of the device.
[0230] (4) The main structural difference between the compound of this application and the compound of the published application CN113402399A is that the connection mode between the diarylamine on one side and the bridging group in the middle is different. By changing the connection mode, the compound of this application has a better high temperature mobility, which is mainly reflected in the better high temperature life when it is made into a device.
[0231] (5) The main structural difference between the compound of this application and the compound of the published application CN111164778A is the different substituents in the branched chain. Through the above changes, the compound of this application has a higher glass transition temperature. A higher glass transition temperature is beneficial to ensure the stability of the device during the packaging and fabrication process, and to prevent the device from aging and cracking due to high temperature fabrication.
[0232] Furthermore, for the aromatic amine organic compounds described in this invention, in addition to the bis-triarylamine bridging groups, optimizing the ligands attached to the triarylamines is beneficial for further improving the material's performance. For example, selecting groups or group derivatives (containing fused or substituted groups) with strong planarity or large structural radii, such as spirofluorene, diphenylfluorene, carbazole, triphenylene, pyrene, and phenanthrene, is more conducive to improving the material's stability and mobility, and also facilitates precise control of the material's HOMO energy level, thereby achieving good device application results.
[0233] The organic functional materials constituting OLED devices include not only hole injection conducting materials but also electron injection conducting materials and light-emitting layer materials. Good device performance requires a good carrier balance. Therefore, to achieve optimal device performance, specific electronic materials are needed to match the aromatic amine organic compounds described in this invention. Based on the inventors' in-depth research, the electronic materials are preferably materials containing aziridine structural features, such as triazine materials, pyridine materials, pyrazine materials, or derivatives containing these characteristic groups. The aromatic amine organic compounds of this invention, when combined with aziridine ring-based electron transport materials, facilitate the achievement of an optimal balance between electrons and holes, resulting in high efficiency while reducing device voltage and exhibiting excellent lifetime. Attached Figure Description
[0234] Figure 1 This is a cross-sectional view of the organic electroluminescent device of the present invention.
[0235] In the figure, 1 represents the substrate layer; 2 represents the anode layer; 3 represents the hole injection layer; 4 represents the hole transport layer; 5 represents the electron blocking layer; 6 represents the light-emitting layer; 7 represents the hole blocking layer; 8 represents the electron transport layer; 9 represents the electron injection layer; 10 represents the cathode layer; and 11 represents the capping layer.
[0236] Figure 2 This is the NMR spectrum of compound 124. Detailed Implementation
[0237] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit the present invention or its application or use. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.
[0238] It should be noted that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the exemplary embodiments according to this application. As used herein, the singular form is intended to include the plural form as well, unless the context clearly indicates otherwise. Furthermore, it should be understood that when the terms "comprising" and / or "including" are used in this specification, they indicate the presence of features, steps, operations, devices, components, and / or combinations thereof.
[0239] In this invention, unless otherwise stated, HOMO refers to the highest occupied orbital of a molecule, and LUMO refers to the lowest empty orbital of a molecule. Furthermore, in this invention, HOMO and LUMO energy levels are represented by absolute values, and comparisons between energy levels are made by comparing their absolute values. Those skilled in the art know that the larger the absolute value of an energy level, the lower its energy.
[0240] In this invention, when a layer or element is referred to as being "above" another layer or substrate, the layer or element may be located directly above the other layer or substrate, or there may be intermediate layers. Furthermore, it will be understood that when a layer is referred to as being "between" two layers, the layer may be the only layer between the two layers, or there may be one or more intermediate layers. The same reference numerals throughout the drawings denote the same elements.
[0241] In this invention, the terms "upper," "lower," "top," and "bottom," used to describe electrodes, organic electroluminescent devices, and other structures, indicate orientation only in a specific state and do not imply that the structure can only exist in that orientation. Conversely, if the structure can be repositioned, such as by inverting it, the orientation of the structure changes accordingly. Specifically, in this invention, the "bottom" or "lower" side of the electrode refers to the side of the electrode closer to the substrate during fabrication, while the opposite side farther from the substrate is the "top" or "upper" side.
[0242] In this specification, the term "substitution" means that one or more hydrogen atoms on a specified atom or group are replaced by a specified group, provided that the normal valence of the specified atom is not exceeded under the existing conditions.
[0243] In this specification, hole characteristics refer to the characteristics that allow holes formed in the anode to be easily injected into and transported in the light-emitting layer when an electric field is applied, due to conductivity characteristics at the highest occupied molecular orbital (HOMO) level.
[0244] In this specification, electronic characteristics refer to the characteristics that allow electrons formed in the cathode to be readily injected into and transported in the light-emitting layer when an electric field is applied, and which are attributed to conductivity characteristics based on the lowest unoccupied molecular orbital (LUMO) level.
[0245] In this specification, C6-C is substituted or not substituted. 30 aryl and / or substituted or unsubstituted C3-C 30Heteroaryl refers to substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted anthraquinone, substituted or unsubstituted phenanthryl, substituted or unsubstituted tetraphenyl, substituted or unsubstituted pyrene, substituted or unsubstituted biphenyl, substituted or unsubstituted para-triphenyl, substituted or unsubstituted meta-triphenyl, substituted or unsubstituted phenyl, substituted or unsubstituted triphenyl, substituted or unsubstituted peryl, substituted or unsubstituted indole, substituted or unsubstituted furanyl, substituted or unsubstituted thiophene, substituted or unsubstituted pyrrole, substituted or unsubstituted pyrazolyl, substituted or unsubstituted imidazolyl, substituted or unsubstituted triazolyl, substituted or unsubstituted oxazolyl, substituted or unsubstituted thiazolyl, substituted or unsubstituted oxadiazolyl, substituted or unsubstituted thiadiazolyl, substituted or unsubstituted pyridinyl, substituted or unsubstituted... The pyrimidinyl group, substituted or unsubstituted pyrazinyl group, substituted or unsubstituted triazinyl group, substituted or unsubstituted benzofuranyl group, substituted or unsubstituted benzothiophenyl group, substituted or unsubstituted benzimidazolyl group, substituted or unsubstituted indolyl group, substituted or unsubstituted quinolinyl group, substituted or unsubstituted isoquinolinyl group, substituted or unsubstituted quinazolinyl group, substituted or unsubstituted quinolinyl group, substituted or unsubstituted naphridyl group, substituted or unsubstituted benzooxazinyl group, substituted or unsubstituted benzothiazinyl group, substituted or unsubstituted acridineyl group, substituted or unsubstituted benzazinyl group, substituted or unsubstituted benzoxazinyl group, substituted or unsubstituted tyranyl group, substituted or unsubstituted dibenzofuranyl group, substituted or unsubstituted dibenzothiophenyl group, substituted or unsubstituted carbazoleyl group, combinations thereof, or fused rings of the foregoing groups, but not limited thereto.
[0246] In this specification, fluorenyl includes dimethylfluorenyl, diphenylfluorenyl, or spirofluorenyl.
[0247] Organic electroluminescent devices
[0248] The present invention provides an organic electroluminescent device using an aromatic amine compound of general formula (1).
[0249] In one exemplary embodiment of the present invention, the organic electroluminescent device may include an anode, a hole transport region, a light-emitting region, an electron transport region, and a cathode.
[0250] The organic electroluminescent device of the present invention can be a bottom-emitting organic electroluminescent device, a top-emitting organic electroluminescent device, or a multilayer organic electroluminescent device, and there is no specific limitation thereto.
[0251] In the organic electroluminescent device of this invention, any substrate commonly used in organic electroluminescent devices can also be used. Examples include transparent substrates, such as glass or transparent plastic substrates; opaque substrates, such as silicon substrates; and flexible polyimide (PI) film substrates. Different substrates have different mechanical strengths, thermal stability, transparency, surface smoothness, and water resistance. Their application varies depending on their properties. In this invention, a transparent substrate is preferred. There are no particular limitations on the thickness of the substrate.
[0252] anode
[0253] Preferably, the anode can be formed on the substrate. In this invention, the anode and cathode are opposite each other. The anode can be made of a conductor with a high work function to facilitate hole injection, and can be, for example, a metal such as nickel, platinum, copper, zinc, silver or alloys thereof; a metal oxide such as zinc oxide, indium oxide, indium tin oxide (ITO), and indium zinc oxide (IZO); a combination of metal and metal oxide, such as ZnO and Al or ITO and Ag; a conductive polymer such as poly(3-methylthiophene), poly(3,4-(ethylene-1,2-dioxy)thiophene), and polyaniline, but is not limited thereto. The thickness of the anode depends on the material used, typically 50-500 nm, preferably 70-300 nm, and more preferably 100-200 nm. In this invention, a combination of metal and metal oxide, ITO and Ag, is preferred.
[0254] cathode
[0255] The cathode can be made of a conductor with a low work function to facilitate electron injection, and can be, for example, a metal or alloy thereof, such as magnesium, calcium, sodium, potassium, titanium, indium, aluminum, silver, tin, and combinations thereof; multilayer materials, such as LiF / Al, Li₂O / Al, and BaF₂ / Ca, but not limited thereto. The thickness of the cathode depends on the material used, typically 10-50 nm, preferably 15-20 nm.
[0256] Light-emitting area
[0257] In this invention, the light-emitting region can be disposed between the anode and the cathode, and can include at least one host material and at least one guest material. Both the host and guest materials of the light-emitting region in the organic electroluminescent device of this invention can be light-emitting layer materials known in the prior art for organic electroluminescent devices. The host material can be, for example, a thiazole derivative, a benzimidazole derivative, a polydialkylfluorene derivative, or 4,4'-bis(9-carbazolyl)biphenyl (CBP). The host material can be a compound containing anthracene groups. The guest material can be, for example, a quinacridone, coumarin, rubrene, perylene and its derivatives, benzopyran derivatives, rhodamine derivatives, or aminostyrene derivatives.
[0258] In a preferred embodiment of the present invention, the luminescent region contains one or two host material compounds.
[0259] In a preferred embodiment of the present invention, the luminescent region contains two host material compounds, and the two host material compounds form an excitocomplex.
[0260] In a preferred embodiment of the present invention, the host material of the luminescent region is selected from one or more of the following compounds BH-1-BH-11:
[0261] (BH-1) (BH-2) (BH-3)
[0262] (BH-4) (BH-5) (BH-6) (BH-7)
[0263] (BH-8) (BH-9) (BH-10) (BH-11).
[0264] In this invention, the luminescent region may contain phosphorescent or fluorescent guest materials to improve the fluorescence or phosphorescence properties of the organic electroluminescent device. Specific examples of phosphorescent guest materials include metal complexes of iridium, platinum, etc., while those commonly used in the art can be used for fluorescent guest materials. In a preferred embodiment of this invention, the guest material used in the luminescent film layer is selected from one of the following compounds: BD-1 to BD-10.
[0265] (BD-1) (BD-2) (BD-3)
[0266] (BD-4) (BD-5) (BD-6)
[0267] (BD-7) (BD-8) (BD-9) (BD-10).
[0268] In the light-emitting region of the present invention, the ratio of the host material to the guest material is 99:1-70:30, preferably 99:1-85:15 and more preferably 97:3-87:13, based on mass.
[0269] The thickness of the luminescent region can be 10-50 nm, preferably 15-30 nm, but the thickness is not limited to this range.
[0270] Hole transport region
[0271] In the organic electroluminescent device of the present invention, a hole transport region is disposed between the anode and the light-emitting region, and includes a hole injection layer, a hole transport layer and an electron blocking layer.
[0272] Hole injection layer
[0273] The hole injection material used in the hole injection layer (also known as the anode interface buffer layer) is a material capable of fully accepting holes from the anode at low voltages, and the highest occupied molecular orbital (HOMO) of the hole injection material is preferably a value between the work function of the anode material and the HOMO of the adjacent organic material layer. In a preferred embodiment of the invention, the hole injection layer is a mixed film layer of a host organic material and a p-type dopant. For holes to be smoothly injected from the anode into the organic film layer, the HOMO energy level of the host organic material must possess certain characteristics with the p-type dopant to facilitate charge transfer states between the host and dopant materials, achieving ohmic contact between the hole injection layer and the anode, thereby achieving efficient hole injection from the electrode to the hole injection layer. This characteristic is summarized as follows: the difference between the HOMO energy level of the host material and the LUMO energy level of the p-type dopant ≤ 0.4 eV. Therefore, for hole-type host materials with different HOMO energy levels, different p-type dopant materials need to be selected to match them in order to achieve ohmic contact at the interface and improve the hole injection effect.
[0274] Preferably, specific examples of the host organic material include: metalloporphyrins, oligothiophenes, aromatic amine organic materials, hexanitrile hexaazabenzanphenanthrene, quinacridone organic materials, perylene organic materials, anthraquinones, polyanilines, and polythiophene conductive polymers; but are not limited thereto. Preferably, the host organic material is an aromatic amine organic material.
[0275] Preferably, the p-type doped material is a charge-conducting compound selected from quinone derivatives or metal oxides, such as tungsten oxide and molybdenum oxide, but not limited thereto.
[0276] In a preferred embodiment of the present invention, the p-type doped material used is selected from any one of the following compounds P-1 to P-8:
[0277] P-1 P-2 P-3 P-4
[0278] P-5 P-6 P-7 P-8.
[0279] In one embodiment of the present invention, the ratio of the host organic material to the P-type doped material is 99:1-95:5, preferably 99:1-97:3, based on mass.
[0280] In a preferred embodiment of the present invention, the hole injection layer is a mixed film layer of aromatic amine compound and P-type doped material, wherein the aromatic amine compound is an aromatic amine compound of general formula (1).
[0281] The thickness of the hole injection layer of the present invention can be 5-20 nm, preferably 8-15 nm, but the thickness is not limited to this range.
[0282] Hole transport layer
[0283] In the organic electroluminescent device of the present invention, a hole transport layer may be disposed above a hole injection layer. The hole transport material is a suitable material with high hole mobility, capable of accepting holes from the anode or hole injection layer and transporting the holes to the light-emitting layer. Specific examples include, but are not limited to, aromatic amine organic materials, conductive polymers, block copolymers having both conjugated and non-conjugated portions. In a preferred embodiment, the hole transport layer comprises an aromatic amine organic compound of the same general formula (1) as the hole injection layer.
[0284] The thickness of the hole transport layer of the present invention can be 80, 100 or 200 nm, preferably 100-150 nm, but the thickness is not limited to this range.
[0285] Electron blocking layer
[0286] In the organic electroluminescent device of the present invention, an electron blocking layer may be disposed between the hole transport layer and the light-emitting layer, and particularly in contact with the light-emitting layer. By disposing of the electron blocking layer in contact with the light-emitting layer, hole transfer at the interface between the light-emitting layer and the hole transport layer can be precisely controlled. In one embodiment of the present invention, the electron blocking layer material is selected from carbazole-based aromatic amine derivatives. The thickness of the electron blocking layer may be 5-20 nm, preferably 8-15 nm, but the thickness is not limited to this range.
[0287] Electronic transmission area
[0288] In the organic electroluminescent device of the present invention, the electron transport region is disposed between the light-emitting region and the cathode, and includes, but is not limited to, a hole blocking layer, an electron transport layer and an electron injection layer.
[0289] Electron injection layer
[0290] An electron injection layer may be disposed between the electron transport layer and the cathode. The electron injection layer material is typically preferably a material with a low work function, allowing electrons to be easily injected into the organic functional material layer. Preferably, the electron injection layer material is an N-type metal. As the electron injection layer material for the organic electroluminescent device of the present invention, electron injection layer materials known in the prior art for organic electroluminescent devices can be used, such as lithium; lithium salts, such as lithium 8-hydroxyquinoline, lithium fluoride, lithium carbonate, or lithium azide; or cesium salts, such as cesium fluoride, cesium carbonate, or cesium azide. The thickness of the electron injection layer of the present invention may be 0.1-5 nm, preferably 0.5-3 nm, and more preferably 0.8-1.5 nm, but the thickness is not limited to this range.
[0291] Electron transport layer
[0292] An electron transport layer may be disposed above the light-emitting film layer or (if present) a hole-blocking layer. The electron transport layer material is one that readily receives electrons from the cathode and transfers the received electrons to the light-emitting layer. Materials with high electron mobility are preferred. As the electron transport layer of the organic electroluminescent device of the present invention, electron transport layer materials known in the prior art for organic electroluminescent devices can be used, such as metal complexes of hydroxyquinoline derivatives represented by Alq3, BAlq and LiQ, various rare earth metal complexes, triazole derivatives, triazine derivatives such as 2,4-bis(9,9-dimethyl-9H-fluoren-2-yl)-6-(naphth-2-yl)-1,3,5-triazine (CAS No.: 1459162-51-6), imidazole derivatives such as 2-(4-(9,10-bis(naphth-2-yl)anthracene-2-yl)phenyl)-1-phenyl-1H-benzo[d]imidazole (CAS No.: 561064-11-7, commonly known as LG201), oxadiazole derivatives, etc.
[0293] In a preferred organic electroluminescent device of the present invention, the electron transport layer comprises a nitrogen heterocyclic compound of general formula (7);
[0294] In a preferred embodiment of the invention, the electron transport layer comprises any one of the following compounds:
[0295] (E1) (E2) (E3) (E4)
[0296] (E5) (E6) (E7) (E8)
[0297] (E9) (E10) (E11) (E12)
[0298] (E13) (E14) (E15) (E16)
[0299] (E17) (E18) (E19) (E20)
[0300] (E21) (E22) (E23) (E24)
[0301] (E25) (E26) (E27) (E28)
[0302] (E29) (E30) (E31).
[0303] In a more preferred embodiment of the invention, the electron transport layer comprises any one of the following compounds:
[0304] (E2) (E5) (E12) (E16)
[0305] (E23).
[0306] In a preferred embodiment of the invention, in addition to the compounds of general formula (7), the electron transport layer also includes other compounds conventionally used for electron transport layers, such as Alq3, LiQ, preferably LiQ. In a more preferred embodiment of the invention, the electron transport layer consists of one of the compounds of general formula (7) and another of the compounds conventionally used for electron transport layers (preferably LiQ).
[0307] The hole injection and transport rates of the hole transport region containing the aromatic amine organic compounds of the present invention can be well matched with the electron injection and transport rates. Preferably, the hole injection and transport rates of the hole transport region containing the aromatic amine organic compounds of the present invention can be better matched with the electron injection and transport rates of the electron transport region containing the nitrogen heterocyclic compound of general formula (7).
[0308] Therefore, in a particular embodiment of the present invention, using an electron transport region consisting of one or more nitrogen heterocyclic compounds of general formula (7) or composed thereof, in combination with a hole transport region consisting of an aromatic amine organic compound of the present invention, achieves relatively better technical results.
[0309] The thickness of the electron transport layer of the present invention can be 10-80 nm, preferably 20-60 nm, and more preferably 25-45 nm, but the thickness is not limited to this range.
[0310] Cover layer
[0311] To improve the light extraction efficiency of organic electroluminescent devices, a light extraction layer (CPL layer, also known as a capping layer) can be added to the cathode of the device. According to the principles of optical absorption and refraction, the CPL capping layer material should have a higher refractive index and a lower absorption coefficient. Any material known in the art can be used as the CPL layer material, such as Alq3 or N4,N4'-diphenyl-N4,N4'-di(9-phenyl-3-carbazolyl)biphenyl-4,4'-diamine. The thickness of the CPL capping layer is typically 5-300 nm, preferably 20-100 nm, and more preferably 40-80 nm.
[0312] The organic electroluminescent device of the present invention may further include an encapsulation structure. The encapsulation structure may be a protective structure preventing external substances such as moisture and oxygen from entering the organic layer of the organic electroluminescent device. The encapsulation structure may be, for example, a can, such as a glass or metal can; or a thin film covering the entire surface of the organic layer.
[0313] This invention also relates to a method for fabricating an organic electroluminescent device, comprising sequentially laminating an anode, a hole injection layer, a hole transport layer, an electron blocking layer, an organic film layer, an electron transport layer, an electron injection layer, and a cathode, and optionally a capping layer, on a substrate. In this regard, methods such as vacuum deposition, vacuum evaporation, spin coating, casting, LB method, inkjet printing, laser printing, or LITI can be used, but are not limited thereto. In this invention, vacuum evaporation is preferably used to form the various layers. Those skilled in the art can conventionally select the various process conditions in the vacuum evaporation method according to actual needs.
[0314] In addition, it should be noted that the materials used to form each layer described in this invention can be used as a single layer by forming a film on their own, or they can be used as a single layer by mixing with other materials to form a film. They can also be a stacked structure between layers that are formed on their own, a stacked structure between layers that are formed by mixing, or a stacked structure between layers that are formed on their own and layers that are formed by mixing.
[0315] The present invention also relates to a full-color display device having red, green, and blue three pixels, including the organic electroluminescent device of the present invention, particularly a flat panel display device. The display device may further include at least one thin-film transistor. The thin-film transistor may include a gate electrode, a source electrode, and a drain electrode, a gate insulating layer, and an active layer, wherein one of the source electrode and the drain electrode may be electrically connected to the anode of the organic electroluminescent device. The active layer may include crystalline silicon, amorphous silicon, organic semiconductor, or oxide semiconductor, but is not limited thereto.
[0316] Example 1: Synthesis of intermediate N
[0317]
[0318] Under a nitrogen atmosphere, 0.06 mol of starting material F-1 was added to a 500 mL three-necked flask and dissolved in a mixed solvent (300 mL toluene, 90 mL H2O). The mixture was stirred under nitrogen for 1 hour. Then, 0.05 mol of starting material E-1, 0.1 mol of K2CO3, and 0.005 mol of Pd(PPh3)4 were slowly added. The mixture was heated to 90 °C and reacted for 8 hours. The reaction was observed using thin-layer chromatography (TLC) until complete. After natural cooling to room temperature, water was added to the reaction system for extraction. The mixture was separated, and the organic phase was rotary evaporated under reduced pressure until no fraction remained. The obtained substance was purified by silica gel column chromatography to obtain intermediate N-1. LC-MS: Measured value: 328.01 ([M+H) + ); Precision quality: 327.11.
[0319] Intermediate N was prepared using a method similar to that in Example 1, as shown in Table 1 below:
[0320] Table 1
[0321]
[0322] Example 2: Synthesis of Intermediate S
[0323]
[0324]
[0325] (1) In a three-necked flask, under nitrogen protection, add 0.01 mol of raw material G-1, 0.012 mol of raw material H-1, and 150 ml of toluene and stir to mix. Then add 5 × 10⁻⁶ ml of toluene. -5 mol Pd2(dba)3, 5×10 -5 0.03 mol of tri-tert-butylphosphine and 0.03 mol of sodium tert-butoxide were heated to 105 °C and refluxed for 24 hours. A sample was spotted onto a TLC plate, showing no remaining amine compounds, indicating a complete reaction. The mixture was allowed to cool naturally to room temperature, filtered, and the filtrate was rotary evaporated until no fraction remained. The filtrate was then passed through a neutral silica gel column to give intermediate R-1. LC-MS: Measured value: 246.03 ([M+H)) + ); Precision quality: 245.12.
[0326] (2) In a three-necked flask, under nitrogen protection, add 0.01 mol of raw material I-1, 0.012 mol of intermediate R-1, and 150 ml of toluene and stir to mix. Then add 5 × 10⁻⁶ ml of toluene. -5 mol Pd2(dba)3, 5×10 -5 0.03 mol of tri-tert-butylphosphine and 0.03 mol of sodium tert-butoxide were heated to 105 °C and refluxed for 24 hours. A TLC sample was taken; no amine compound remained, indicating the reaction was complete. The mixture was allowed to cool naturally to room temperature, filtered, and the filtrate was rotary evaporated until no fraction remained. The filtrate was then passed through a neutral silica gel column to give intermediate S-1. LC-MS: Measured value: 448.11 ([M+H)) + ); Precision quality: 447.24.
[0327]
[0328]
[0329] (1) In a three-necked flask, under nitrogen protection, add 0.01 mol of raw material G-3, 0.012 mol of raw material H-4, and 150 ml of toluene and stir to mix. Then add 5 × 10 -5 mol Pd2(dba)3, 5×10 -5 0.03 mol of tri-tert-butylphosphine and 0.03 mol of sodium tert-butoxide were heated to 105 °C and refluxed for 24 hours. A TLC sample was taken; no amine compound remained, indicating the reaction was complete. The mixture was allowed to cool naturally to room temperature, filtered, and the filtrate was rotary evaporated until no fraction remained. The filtrate was then passed through a neutral silica gel column to give intermediate R-4. LC-MS: Measured value: 406.22 ([M+H)) + ); Precision quality: 405.17.
[0330] (2) 10 mmol of intermediate R-4 and 12 mmol of starting material I-2 were added to a three-necked flask and dissolved in a mixed solvent (70 mL toluene, 35 mL ethanol). Then, 0.1 mmol of Pd(PPh3)4 and 15 mL of 3 mol / L K2CO3 aqueous solution were added. The mixture was heated under nitrogen protection and refluxed for 12 hours. A sample was spotted onto a TLC plate to confirm the completeness of the reaction. After cooling to room temperature, the reaction mixture was filtered through a diatomaceous earth filter, washed with chloroform, and the resulting filtrate was evaporated under vacuum. The residue was purified by column chromatography on silica gel using hexane / toluene as the eluent to obtain intermediate S-4. LC-MS: Measured value: 488.10 ([M+H) + ); Precision quality: 487.23.
[0331] Intermediate S was prepared using a method similar to that in Example 2, as shown in Table 2 below:
[0332] Table 2
[0333]
[0334] Example 3: Synthesis of intermediate Z-1
[0335]
[0336]
[0337]
[0338] (1) Under a nitrogen atmosphere, 0.06 mol of raw material J was added to a 500 mL three-necked flask, and dissolved in a mixed solvent (300 mL toluene, 90 mL H2O). The mixture was stirred under nitrogen for 1 hour, and then 0.05 mol of raw material K-1, 0.1 mol of K2CO3, and 0.005 mol of Pd(PPh3)4 were slowly added. The mixture was heated to 90 °C and reacted for 8 hours. The reaction was observed using thin-layer chromatography (TLC) until complete. After natural cooling to room temperature, water was added to the reaction system for extraction. The mixture was separated, and the organic phase was rotary evaporated under reduced pressure until no fraction remained. The obtained substance was purified by silica gel column chromatography to obtain intermediate M-1. LC-MS: Measured value: 222.85 ([M+H) + ); Precision quality: 221.97.
[0339] (2) In a flask, add 0.06 mol of intermediate M-1 and 300 mL of anhydrous tetrahydrofuran. Cool to -78°C under nitrogen protection. Slowly add 0.06 mol of 2.5 M n-butylhexane solution. Maintain this temperature and stir for 2 h. Then add 0.06 mol of raw material P to this solution. After the addition is complete, react at room temperature for 2 h. Add 1 N hydrochloric acid solution to the reaction solution, extract with dichloromethane, dry, concentrate, add 0.3 mL of acetic acid and 0.1 mL of concentrated hydrochloric acid to the crude product, heat under reflux for 5 h, cool, filter, recrystallize with ethanol and tetrahydrofuran, and dry to obtain intermediate T-1. LC-MS: Measured value: 341.15 ([M+H) + ); Precision quality: 340.07.
[0340] (3) In a 250ml three-necked flask, under nitrogen protection, add 0.01mol of raw material H-1, 0.012mol of intermediate T-1, and 150ml of toluene and stir to mix. Then add 5×10 -5 mol Pd2(dba)3, 5×10 -5 0.03 mol of tri-tert-butylphosphine and 0.03 mol of sodium tert-butoxide were heated to 105 °C and refluxed for 24 hours. A TLC sample was taken; no amine compound remained, indicating the reaction was complete. The mixture was allowed to cool naturally to room temperature, filtered, and the filtrate was rotary evaporated until no fraction remained. The filtrate was then passed through a neutral silica gel column to give intermediate Z-1. LC-MS: Measured value: 398.28 ([M+H)) + ); Precision quality: 397.15.
[0341] Intermediate Z-2 was prepared using a method similar to that in Example 3, as shown in Table 3 below:
[0342] Table 3
[0343]
[0344] Example 4: Synthesis of Compound 4
[0345]
[0346]
[0347]
[0348] (1) Under a nitrogen atmosphere, 0.06 mol of raw material A-1 was added to a 500 mL three-necked flask, and dissolved in a mixed solvent (300 mL toluene, 90 mL H2O). The mixture was stirred under nitrogen for 1 hour, and then 0.05 mol of raw material B-1, 0.1 mol of K2CO3, and 0.005 mol of Pd(PPh3)4 were slowly added. The mixture was heated to 90 °C and reacted for 8 hours. The reaction was observed using thin-layer chromatography (TLC) until complete. After natural cooling to room temperature, water was added to the reaction system for extraction. The mixture was separated, and the organic phase was rotary evaporated under reduced pressure until no fraction remained. The obtained substance was purified by silica gel column chromatography to obtain intermediate X-1. LC-MS: Measured value: 266.81 ([M+H) + ); Precision quality: 265.95.
[0349] (2) Under a nitrogen atmosphere, 0.06 mol of intermediate X-1 was added to a 500 mL three-necked flask, and dissolved in a mixed solvent (300 mL toluene, 90 mL H2O). The mixture was stirred under nitrogen for 1 hour, then 0.05 mol of raw material C-1, 0.1 mol of K2CO3, and 0.005 mol of Pd(PPh3)4 were slowly added. The mixture was heated to 90 °C and reacted for 8 hours. The reaction was observed using thin-layer chromatography (TLC) until complete. After natural cooling to room temperature, water was added to the reaction system for extraction. The mixture was separated, and the organic phase was rotary evaporated under reduced pressure until no fraction remained. The obtained substance was purified by silica gel column chromatography to obtain intermediate Y-1. LC-MS: Measured value: 432.23 ([M+H) + ); Precision quality: 431.14.
[0350] (3) In a 250ml three-necked flask, under nitrogen protection, add 0.01mol of raw material D-1, 0.012mol of intermediate Y-1, and 150ml of toluene and stir to mix. Then add 5×10 -5 mol Pd2(dba)3, 5×10 -5 0.03 mol of tri-tert-butylphosphine and 0.03 mol of sodium tert-butoxide were heated to 105 °C and refluxed for 24 hours. A TLC sample was taken, showing no remaining amine compounds, indicating a complete reaction. The mixture was allowed to cool naturally to room temperature, filtered, and the filtrate was rotary evaporated until no fraction remained. The filtrate was then passed through a neutral silica gel column to give compound 4. Elemental analysis of the structure (molecular formula C...) 61 H 42 N2): Theoretical values: C, 91.24; H, 5.27; N, 3.49; Measured values: C, 91.26; H, 5.23; N, 3.51. LC-MS: Measured value: 803.12 ([M+H]) + ); Precision quality: 802.33.
[0351] The following compounds were prepared using a method similar to that in Example 4, as shown in Table 4 below:
[0352] Table 4
[0353]
[0354]
[0355]
[0356] Detection methods
[0357] Glass transition temperature Tg: Measured by differential scanning calorimetry (DSC, Netzsch DSC204F1 differential scanning calorimeter, Germany), with a heating rate of 10℃ / min. HOMO level: Measured using an ionization energy testing system (IPS3) in a vacuum environment. Eg level: Measured using a double-beam UV-Vis spectrophotometer (model: TU-1901), calculated by drawing a tangent between the baseline of the UV spectrophotometry (UV absorption) of the material's single film and the rising side of the first absorption peak, using the value at the intersection of the tangent and the baseline. Hole mobility: Measured using the space charge confined current method (SCLC) after fabricating the material into a single-charge device. Triplet level T1: Measured using a Horiba Fluorolog-3 series fluorescence spectrometer, with a test condition of 2×10⁻⁶. - 5 A mol / L toluene solution.
[0358] See Table 5 for specific physical property test results.
[0359] Table 5
[0360]
[0361] As shown in Table 5 above, the compounds of the present invention have suitable HOMO energy levels, high hole mobility and wide band gap (Eg), which can realize organic electroluminescent devices with high efficiency, low voltage and long lifetime.
[0362] Figure 2 The NMR spectrum of compound 124 of this invention is obtained from... Figure 2 It can be seen that, 1H NMR (400 MHz, Chloroform-d) δ7.78 (d, 2H),7.73(d,1H),7.68(d,1H),7.37–7.33(m,3H), .24 –7.17(m, 6H), 7.16 – 7.11 (m, 6H), 7.10 – 7.06 (m, 2H), 7.05 – 7.00 (m, 6H), 6.99 – 6.93 (m, 4H), 6.91 –6.79 (m, 9H), 6.72 (d, 1H), 6.65 (d, 1H).
[0363] Fabrication of organic electroluminescent devices
[0364] The molecular structures of the materials involved in the following preparation process are shown below:
[0365] EB-1
[0366]
[0367] HT-1 HT-2 HT-3
[0368] HT-4 HT-5 HT-6
[0369] Device Comparison Example 1
[0370] Organic electroluminescent devices are prepared according to the following steps:
[0371] like Figure 1As shown, substrate layer 1 is used to wash anode layer 2 (Ag (100nm)), which involves sequentially performing alkaline washing, pure water washing, drying, and then ultraviolet-ozone washing to remove organic residues from the surface of the anode layer. After the above washing, a hole injection layer 3 (HT-1 and P-1 with a mass ratio of 97:3) is deposited on anode layer 2 using a vacuum evaporation apparatus, with a thickness of 10nm. Next, a hole transport layer 4 (HT-1 with a thickness of 117nm) is deposited. Following this, an electron blocking layer 5 (EB-1 with a thickness of 10nm) is deposited. After the electron blocking material deposition, the light-emitting layer 6 of the OLED light-emitting device is fabricated. Its structure includes BH-1 as the host material and BD-1 as the dopant material, with a doping ratio of 3% by weight, and a light-emitting layer thickness of 20nm. After the light-emitting layer 6, HB1 is deposited with a thickness of 8nm as the hole blocking layer 7. Above the hole-blocking layer 7, ET-1 and Liq are further deposited by vacuum evaporation, with an ET-1 to Liq mass ratio of 1:1. The vacuum-deposited film thickness of this material is 30 nm, and this layer serves as the electron transport layer 8. On the electron transport layer 8, a LiF layer with a thickness of 1 nm is fabricated using a vacuum evaporation apparatus; this layer serves as the electron injection layer 9. On the electron injection layer 9, a Mg:Ag electrode layer with a thickness of 16 nm is fabricated using a vacuum evaporation apparatus, with a Mg to Ag mass ratio of 1:9; this layer serves as the cathode layer 10. On the cathode layer 10, CP-1 with a thickness of 70 nm is vacuum-deposited as a capping layer 11.
[0372] Device Comparison Examples 2-6
[0373] The method was carried out according to the device comparison example 1, except that the organic materials in the hole injection layer and the hole transport layer were replaced with the organic materials shown in Table 5.
[0374] Device Examples 1-27
[0375] The method was carried out according to the device comparison example 1, except that the organic materials in the hole injection layer, hole transport layer or electron transport layer were replaced with the organic materials shown in Table 6.
[0376] Table 6
[0377]
[0378]
[0379] Taking Example 1 as an example in the table above, "P-1:4=3:97 10nm" in the second column indicates that the material used for the hole injection layer is compound 4 and p-type dopant P-1, 3:97 refers to the weight ratio of p-type dopant to compound 4 as 3:97, and 10nm represents the thickness of the layer; "4 117nm" in the third column indicates that the material used is compound 4, and the thickness of the layer is 117nm. The meanings in the other tables can be deduced similarly.
[0380] After fabricating the OLED light-emitting device as described above, the cathode and anode were connected using a known driving circuit, and various performance parameters of the device were measured. The performance measurement results of the devices in Examples 1-27 and Comparative Examples 1-6 are shown in Table 7.
[0381] Table 7
[0382]
[0383] Note: LT95 refers to the time it takes for the device's brightness to decay to 95% of its original brightness when the brightness is 1500 nits.
[0384] Voltage, current efficiency, and color coordinates were measured using an IVL (current-voltage-luminance) testing system (Suzhou Fushida Scientific Instruments Co., Ltd.); the current density was 10 mA / cm². 2 ;
[0385] The lifetime testing system is the EAS-62C OLED lifetime testing system from Japan Systems Research Co., Ltd.
[0386] High-temperature life refers to the lifespan of a device at 80°C and a current density of 10 mA / cm². 2 The time it takes for the device's brightness to decrease to 80% of its original brightness;
[0387] As can be seen from the results in Table 7 (Comparative Examples 1-5 and Device Examples 1-27), using the aromatic amine organic compounds of the present invention as hole injection and hole transport layer materials effectively reduces device voltage and improves device efficiency and lifetime due to their high carrier transport rate. Compared to Comparative Example 6, Device Examples 1-22 effectively improve the high-temperature lifetime of the device. Furthermore, in particular, the combination of the structure of the present invention with specific electron transport layer materials in Examples 23-27 significantly reduces device voltage.
Claims
1. An aromatic amine organic compound, characterized in that, The structure of the compound is shown in any one of general formulas (3-7) to (3-8): General formula (3-7) General formula (3-8) In general formula (3-7), R2-R3 are independently represented as one of substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, or substituted or unsubstituted diphenyl; R4 represents one of the following: substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted diphenyl, substituted or unsubstituted benzofuranyl, substituted or unsubstituted dibenzofuranyl, or substituted or unsubstituted benzothiopheneyl. R5 and R6 are independently represented as hydrogen atom, deuterium atom, and phenyl, respectively, and R5 and R6 are not simultaneously hydrogen atom and deuterium atom; The substituents used for the substituent groups are selected from one or more of deuterium atoms, phenyl groups, and naphthyl groups; In general formula (3-8), R1 and R4 are independently represented as one of substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, or substituted or unsubstituted diphenyl; R2 represents one of the following: substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, substituted or unsubstituted diphenyl, substituted or unsubstituted benzofuranyl, substituted or unsubstituted dibenzofuranyl, or substituted or unsubstituted benzothiopheneyl. R5 and R6 are independently represented as hydrogen atom, deuterium atom, and phenyl, respectively, and R5 and R6 are not simultaneously hydrogen atom and deuterium atom; The substituents used for the substituent groups are selected from one or more of deuterium, phenyl, and naphthyl groups.
2. The aromatic amine organic compound according to claim 1, characterized in that, In general formulas (3-7), R2-R4 are each independently represented as one of substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, or substituted or unsubstituted diphenyl. R5 and R6 are independently represented as either a hydrogen atom or a phenyl group, and R5 and R6 are not both hydrogen atoms at the same time; The substituents used for the substituent groups are selected from one or more of deuterium atoms, phenyl groups, and naphthyl groups; In general formula (3-8), R1, R2, and R4 are each independently represented as one of substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, or substituted or unsubstituted diphenyl. R5 and R6 are independently represented as either a hydrogen atom or a phenyl group, and R5 and R6 are not both hydrogen atoms at the same time; The substituents used for the substituent groups are selected from one or more of deuterium, phenyl, and naphthyl groups.
3. The aromatic amine organic compound according to claim 1, characterized in that, The specific structure of the compound is any one of the following structures: （1） （2） （3） （4） （5） （6） （7） （8） （9） （10） （11） （12） （13） （14） （15） （16） （17） （18） （19） （20） （21） （22） （23） （24） （25） （26） （27） （28） （41） （42） （43） （44） （45） （46） （47） （48） （57） （58） （59） （60） （61） （62） （63） （64） （65） （66） （67） （68） （69） （70） （71） （72） （73） （74） （75） （76） （77） （78） （79） （80） （81） （82） （83） （84） （97） （98） （99） （100） （101） （102） （103） （104） （113） （114） （115） （116） （117） （118） （119） （120） （121） （122） （123） （124） （125） （126） （127） （128） （129） （130） （131） （132） （133） （134） （135） （136） （137） （138） （139） （140） （141） （142） （143） （144） （145） （146） （147） （148） （161） （162 ） （163） （164） （165） （166） （167） （168） （177） （178） （179） （180） （181） （182） （183） （184） （185） （186） （187） （188） （189） （190） （191） （192） （193） （194） （195） （196） （197） （198） （199） （200） （201） （202） （203） （204） （217） （218） （219） （220） （221） （222） （223） （224） （233） （234） （235） （236） （237） （238） （239） （240） （241） （242） （243） （244） （245） （246） （247） （248） （249） （250） （251） （252） （253） （254） （255） （256） （257） （258） （259） （260） （261） （262） （263） （264） （265） （266） （267） （280） （281） （282） （283） （284） （285） （286） （287） （296） （297） （298） （299） （300） （301） （302） （303） （304） （305） （306） （307） （308） （309） （310） （311） （312） （313） （314） （315） （316） （317） （318） （319） （320） （321） （322） （323） （324） （337） （338） （339） （340） （341） （342） （343） （344） （353） （354） （355） （356） （357） （358） （359） （360） （361） （362） （363） （364） （365） （366） （367） （368） （369） （370） （371） （372） （373） （374） （375） （376） （377） （378） （379） （380） （381） （382） （383） （384） （385） （386） （387） （388） （401） （402） （403） （404） （405） （406） （407） （408） （417） （418） （419） （420） （421） （422） （423） （424） （425） （426） （427） （428） （429） （430） （431） （432） （433） （434） （435） （436） （437） （438） （439） （440） （441） （442） （443） （444） （457） （458） （459） （460） （461） （462） （463） （464） （473） （474） （475） （476） （477） （478） （479） （480） （481） （483） （486） （489） （504）。 4. An aromatic amine organic compound, characterized in that, The specific structure of the compound is any one of the following structures: （228） （271） （392） （499） （503）。 5. An organic electroluminescent device, comprising, in sequence, an anode, a hole transport region, a light-emitting region, an electron transport region, and a cathode, characterized in that, The hole transport region comprises any one of the aromatic amine organic compounds according to claims 1-4.
6. The organic electroluminescent device according to claim 5, characterized in that, The hole transport region includes a hole injection layer, a hole transport layer, and an electron blocking layer, wherein the hole transport layer and the hole injection layer comprise any one of the aromatic amine organic compounds according to claims 1-4.
7. The organic electroluminescent device according to claim 6, characterized in that, The hole transport layer comprises an aromatic amine organic compound as described in any one of claims 1-4, and the hole injection layer is composed of an aromatic amine organic compound as described in any one of claims 1-4 and other P-type doped materials used for the hole injection layer.
8. The organic electroluminescent device according to claim 5, characterized in that, The electron transport region comprises nitrogen heterocyclic compounds represented by general formula (7): General formula (7) Ar1, Ar2, and Ar3 are independently selected from substituted or unsubstituted C6-C. 30 Aryl, substituted or unsubstituted C3-C containing one or more heteroatoms 30 One of the heteroaryl groups; L1 represents C6-C with a single bond, substitution, or no substitution. 30 aryl, substituted or unsubstituted C3-C containing one or more heteroatoms 30 One of the heteroaryl groups; X1, X2, and X3 independently represent N or CH, and at least one of X1, X2, and X3 represents N; Each heteroatom is independently selected from N, O, or S; The substituents used for the substituent groups are one or more of the following: deuterium atom, phenyl, naphthyl, biphenyl, dibenzofuranyl, dibenzothiophenyl, pyridyl, and pyrimidinyl.