CN112151682A

CN112151682A - Organic electroluminescent device comprising hole blocking layer and electron transport layer

Info

Publication number: CN112151682A
Application number: CN201910547378.6A
Authority: CN
Inventors: 王静; 夏传军; 邝志远; 庞惠卿
Original assignee: Beijing Xiahe Technology Co ltd
Current assignee: Xiahe Technology Jiangsu Co ltd
Priority date: 2019-06-26
Filing date: 2019-06-26
Publication date: 2020-12-29
Anticipated expiration: 2039-06-26
Also published as: CN112151682B

Abstract

An organic electroluminescent device comprising a hole blocking layer and an electron transport layer is disclosed. The device comprises an anode, a cathode, and an organic layer arranged between the anode and the cathode, wherein the organic layer at least comprises a first organic layer and a second organic layer, and the first organic layer and the second organic layer both comprise compounds with specific structures. The combination of the hole blocking layer containing specific structural materials and the electron transmission layer is selected, so that the concentration of carriers in the light-emitting layer is effectively regulated and controlled to achieve the expected balance, and compared with the prior art, the combination property of the organic electroluminescent device is obviously improved. A display assembly is also disclosed.

Description

Organic electroluminescent device comprising hole blocking layer and electron transport layer

Technical Field

The present invention relates to an organic electronic device. And more particularly, to an organic electroluminescent device comprising a hole blocking layer and an electron transport layer.

Background

Organic electronic devices include, but are not limited to, the following classes: organic Light Emitting Devices (OLEDs), organic field effect transistors (O-FETs), Organic Light Emitting Transistors (OLETs), Organic Photovoltaics (OPVs), dye-sensitized solar cells (DSSCs), organic optical detectors, organic photoreceptors, organic field effect devices (OFQDs), light emitting electrochemical cells (LECs), organic laser diodes, and organic plasma light emitting devices.

Organic light emitting devices have advantages of wide angle, high contrast, and faster response time. Tang and Van Slyke of Issman Kodak in 1987 reported an organic light emitting device with an arylamine hole transport layer and a tris-8-hydroxyquinoline-aluminum layer as an electron transport layer and a light emitting layer (Applied Physics Letters, 1987,51(12): 913-915). Upon biasing the device, green light is emitted from the device. The invention lays a foundation for the development of modern Organic Light Emitting Diodes (OLEDs). Since OLEDs are a self-emissive solid state device, it offers great potential for display and lighting applications. Furthermore, the inherent properties of organic materials, such as their flexibility, may make them well suited for particular applications, such as in the fabrication of flexible substrates.

Organic electroluminescent devices convert electrical energy into light by applying a voltage across the device. In general, an organic electroluminescent device includes an anode, a cathode, and an organic layer between the anode and the cathode. The organic layer of the organic electroluminescent device may include a hole injection layer, a hole transport layer, an electron blocking layer, a light emitting layer, an electron buffer layer, a hole blocking layer, an electron transport layer, an electron injection layer, and the like. Materials constituting the organic layer may be classified into a hole injection material, a hole transport material, an electron blocking material, a light emitting material, an electron buffer material, a hole blocking material, an electron transport material, a hole blocking material, and the like according to the function of the material. When a bias is applied to the device, holes are injected from the anode into the light-emitting layer and electrons are injected from the cathode into the light-emitting layer. The holes and electrons meet to form excitons, which recombine to emit light.

The hole blocking layer and the electron transport layer are important functional layers influencing the performance of the organic electroluminescent device, and the selection and the matching of materials of the hole blocking layer and the electron transport layer seriously influence the driving voltage, the efficiency and the service life of the organic electroluminescent device. It is commercially desirable to obtain an organic electroluminescent device having characteristics of low driving voltage, high efficiency, long service life, etc., and it is very important to develop a novel hole blocking layer and electron transport layer material, and it is also very important to select a suitable hole blocking layer and electron transport layer combination for achieving the above objects.

The inventor of the application notices the matching of the hole blocking materials and specific electron transport materials which also have triazine and other nitrogen heterocycles as basic frameworks, but does not research the matching of the compounds as the hole blocking materials and other specific structure types, particularly silicon heterocycle-containing electron transport materials.

Chinese patent application CN 109671851 a discloses a series of carbazole compounds that can be used as hole blocking materials, but this application only studies the combined use of such compounds with three common electron transport materials, and does not study the coordination of the carbazole compounds as hole blocking materials with electron transport materials of specific structures.

U.S. Pat. No. 4, 9960363, 2 discloses compounds which can be used as hole blocking materials, the basic backbone of which is formed by the combination of a fluorene moiety with a six-membered nitrogen heteroaromatic ring, either directly or via a linking group, but the application is not concerned with the coordination of such compounds as hole blocking materials with electron transport materials of specific structure.

Chinese patent application CN201811235650.9, the entire content of which is incorporated herein by reference, is a prior patent application to the present applicant. Although this application discloses a series of silicon-containing compounds that can be used as electron transport layer materials, this application does not focus on the coordination of the silicon-containing compounds as electron transport layer materials with hole blocking layer materials of specific structures.

Chinese patent application CN201910149767.3, the entire content of which is incorporated herein by reference, is a prior patent application to the present applicant. Although this application discloses a series of organic compounds that can be used as hole blocking layer materials, this application does not focus on the coordination of the organic compounds as hole blocking layer materials with electron transport layer materials of a specific structure.

Through intensive research, the inventor finds that the combination of the compound containing the structure of the formula 1 as a hole blocking layer material and the compound containing the structure of the formula 2 as an electron transport layer material can be applied to an organic electroluminescent device, so that the comprehensive performance of the organic electroluminescent device can be obviously improved.

Disclosure of Invention

An object of the present invention is to provide an organic electroluminescent device comprising: the organic layer at least comprises an organic layer I and an organic layer II;

wherein the first organic layer comprises a compound having a structure represented by formula 1:

in the formula 1, the reaction mixture is,

wherein X is independently selected from NR ', CR "R'", O, S or Se;

wherein R ', R "and R'" are each independently selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted aralkyl groups having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy groups having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy groups having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl groups having 2 to 20 carbon atoms, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine groups having 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, nitriles, isonitriles, thio groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof;

when X is CR "R '", R "and R'" can optionally be joined to form a ring;

wherein X_a1To X_a8Each independently is CR₁Or N; wherein X_a1-X_a8At least one of which is CR₁And R is₁Is represented by formula 1Structure represented by A:

in formula 1A, represents the CR₁In the structure of the formula₁The position of the linkage to C;

wherein L' is a single bond, or is a substituted or unsubstituted arylene group having 6 to 60 carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 60 carbon atoms;

wherein Ar is₁And Ar₂Each independently selected from the group consisting of: substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, and combinations thereof;

wherein X_a1To X_a8The rest of R present in₁Each independently selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted aralkyl groups having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy groups having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy groups having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl groups having 2 to 20 carbon atoms, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine groups having 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, nitriles, isonitriles, thio groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof;

two adjacent substituents R₁Can optionally be linked to form a ring;

wherein the second organic layer comprises a compound having a structure represented by formula 2:

in the formula 2, the first step is,

wherein n is 1,2, 3 or 4; when n is 2 or more, each group L and B may be the same or different;

wherein L is a single bond, or is a substituted or unsubstituted arylene group having 6 to 60 carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 60 carbon atoms;

wherein B is a substituted or unsubstituted electron deficient heteroaryl group having 2 to 60 carbon atoms;

wherein a is a structure represented by formula 2A:

in the formula 2A, the reaction mixture is,

wherein ring D and ring E each independently represent a substituted or unsubstituted aryl group having 5 to 50 ring atoms, or a substituted or unsubstituted heteroaryl group having 5 to 50 ring atoms;

wherein at least one of ring D and ring E is a fused ring system;

wherein R is₂And R_2AEach independently selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted aralkyl groups having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy groups having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy groups having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl groups having 2 to 20 carbon atoms, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine, acyl, carbonyl, carboxylic acid, ester, nitrile, isonitrile, thio, sulphenylene having 0 to 20 carbon atomsSulfonyl, phosphino, and combinations thereof;

R₂and R_2ACan optionally be linked to form a ring.

The invention also provides a display component comprising the organic electroluminescent device.

In the organic electroluminescent device disclosed by the invention, the organic compound containing the structure of the formula 2 is used as an electron transport layer and the organic compound containing the structure of the formula 1 is used as a hole blocking layer in combination. The combination of the hole blocking layer containing specific structural materials and the electron transmission layer is selected, so that the concentration of carriers in the light-emitting layer is effectively regulated and controlled to achieve the expected balance.

Drawings

Fig. 1 is a schematic view of a conventional organic light emitting device.

Fig. 2 is a schematic diagram of a conventional tandem organic light emitting device.

Fig. 3 is a schematic view of another prior art tandem organic light emitting device.

Detailed Description

OLEDs can be fabricated on a variety of substrates, such as glass, plastic, and metal. Fig. 1 schematically, but without limitation, illustrates an organic light emitting device 100. The figures are not necessarily to scale, and some of the layer structures in the figures may be omitted as desired. The device 100 may include a substrate 101, an anode 110, a hole injection layer 120, a hole transport layer 130, an electron blocking layer 140, an emissive layer 150, a hole blocking layer 160, an electron transport layer 170, an electron injection layer 180, and a cathode 190. The device 100 may be fabricated by sequentially depositing the described layers. The nature and function of the layers, as well as exemplary materials, are described in more detail in U.S. patent US7,279,704B2, columns 6-10, which is incorporated herein by reference in its entirety.

There are more instances of each of these layers. For example, a flexible and transparent substrate-anode combination is disclosed in U.S. Pat. No. 5,844,363, which is incorporated by reference in its entirety. Warp pAn example of a doped hole transport layer is doped with F at a molar ratio of 50:1₄TCNQ m-MTDATA as disclosed in U.S. patent application publication No. 2003/0230980, which is incorporated by reference in its entirety. Examples of host materials are disclosed in U.S. patent No. 6,303,238 to Thompson et al, which is incorporated by reference in its entirety. An example of an n-doped electron transport layer is BPhen doped with Li at a molar ratio of 1:1, as disclosed in U.S. patent application publication No. 2003/0230980, which is incorporated by reference in its entirety. U.S. Pat. Nos. 5,703,436 and 5,707,745, which are incorporated by reference in their entirety, disclose examples of cathodes including composite cathodes having a thin layer of a metal such as Mg: Ag and an overlying layer of transparent, conductive, sputter-deposited ITO. The principles and use of barrier layers are described in more detail in U.S. patent No. 6,097,147 and U.S. patent application publication No. 2003/0230980, which are incorporated by reference in their entirety. Examples of injection layers are provided in U.S. patent application publication No. 2004/0174116, which is incorporated by reference in its entirety. A description of the protective layer may be found in U.S. patent application publication No. 2004/0174116, which is incorporated by reference in its entirety.

The above-described hierarchical structure is provided via non-limiting embodiments. The function of the OLED may be achieved by combining the various layers described above, or some layers may be omitted entirely. It may also include other layers not explicitly described. Within each layer, a single material or a mixture of materials may be used to achieve optimal performance. Any functional layer may comprise several sub-layers. For example, the light emitting layer may have two layers of different light emitting materials to achieve a desired light emission spectrum.

In one embodiment, an OLED may be described as having an "organic layer" disposed between a cathode and an anode. The organic layer may include one or more layers.

In one embodiment, two or more OLED cells can be connected in series to form a series OLED, as shown schematically and without limitation in FIG. 2 for a series OLED device 500. The device 500 may include a substrate 101, an anode 110, a first unit organic light emitting device 100, a charge generation layer 300, a second unit organic light emitting device 200, and a cathode 290. The first unit 100 includes a hole injection layer 120, a hole transport layer 130, an electron blocking layer 140, an emission layer 150, a hole blocking layer 160, and an electron transport layer 170, the second unit 200 includes a hole injection layer 220, a hole transport layer 230, an electron blocking layer 240, an emission layer 250, a hole blocking layer 260, an electron transport layer 270, and an electron injection layer 280, and the charge generation layer 300 includes an N-type charge generation layer 310 and a P-type charge generation layer 320. The device 500 may be fabricated by sequentially depositing the described layers.

The OLED may also be provided with an encapsulation layer, as shown schematically and non-limitingly in fig. 3 for an organic light emitting device 600, which differs from fig. 2 in that an encapsulation layer 102 may also be included over the cathode 290 to protect against harmful substances from the environment, such as moisture and oxygen. Any material capable of providing an encapsulation function may be used as the encapsulation layer, such as glass or a hybrid organic-inorganic layer. The encapsulation layer should be placed directly or indirectly outside the OLED device. Multilayer film encapsulation is described in U.S. patent US7,968,146B2, the entire contents of which are incorporated herein by reference.

Devices manufactured according to embodiments of the present invention may be incorporated into various consumer products having one or more electronic component modules (or units) of the device. Some examples of such consumer products include flat panel displays, monitors, medical monitors, televisions, billboards, lights for indoor or outdoor lighting or signaling, heads-up displays, fully or partially transparent displays, flexible displays, smart phones, tablet computers, tablet handsets, wearable devices, smart watches, laptop computers, digital cameras, camcorders, viewfinders, microdisplays, 3-D displays, vehicle displays, and taillights.

The materials and structures described herein may also be used in other organic electronic devices as previously listed.

As used herein, "top" means furthest from the substrate, and "bottom" means closest to the substrate. Where a first layer is described as being "disposed on" a second layer, the first layer is disposed farther from the substrate. Other layers may be present between the first and second layers, unless it is specified that the first layer is "in contact with" the second layer. For example, a cathode can be described as being "disposed on" an anode even though various organic layers are present between the cathode and the anode.

As used herein, "solution processable" means capable of being dissolved, dispersed or transported in and/or deposited from a liquid medium in the form of a solution or suspension.

A ligand may be referred to as "photoactive" when it is believed that the ligand directly contributes to the photoactive properties of the emissive material. A ligand may be referred to as "ancillary" when it is believed that the ligand does not contribute to the photoactive properties of the emissive material, but the ancillary ligand may alter the properties of the photoactive ligand.

It is believed that the Internal Quantum Efficiency (IQE) of fluorescent OLEDs can be limited by delaying fluorescence beyond 25% spin statistics. Delayed fluorescence can generally be divided into two types, i.e., P-type delayed fluorescence and E-type delayed fluorescence. P-type delayed fluorescence results from triplet-triplet annihilation (TTA).

On the other hand, E-type delayed fluorescence does not depend on collision of two triplet states, but on conversion between triplet and singlet excited states. Compounds capable of producing E-type delayed fluorescence need to have a very small mono-triplet gap in order to switch between energy states. Thermal energy can activate a transition from a triplet state back to a singlet state. This type of delayed fluorescence is also known as Thermally Activated Delayed Fluorescence (TADF). A significant feature of TADF is that the retardation component increases with increasing temperature. If the reverse intersystem crossing (IRISC) rate is fast enough to minimize non-radiative decay from the triplet state, then the fraction of the backfill singlet excited state may reach 75%. The total singlet fraction may be 100%, far exceeding 25% of the spin statistics of the electrogenerated excitons.

The delayed fluorescence characteristic of type E can be found in excited complex systems or in single compounds. Without being bound by theory, it is believed that E-type delayed fluorescence requires the light emitting material to have a small mono-triplet energy gap (Δ Ε)_S-T). Organic non-metal containing donor-acceptor emissive materials may be able to achieve this. General emission of these materialsCharacterized by donor-acceptor Charge Transfer (CT) type emission. Spatial separation of HOMO from LUMO in these donor-acceptor type compounds generally results in small Δ E_S-T. These states may include CT states. Generally, donor-acceptor light emitting materials are constructed by linking an electron donor moiety (e.g., an amino or carbazole derivative) to an electron acceptor moiety (e.g., a six-membered, N-containing, aromatic ring).

Definitions for substituent terms

Halogen or halide-as used herein, includes fluorine, chlorine, bromine and iodine.

Alkyl-comprises both straight and branched chain alkyl groups. Examples of alkyl groups include methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, n-heptadecyl, n-octadecyl, neopentyl, 1-methylpentyl, 2-methylpentyl, 1-pentylhexyl, 1-butylpentyl, 1-heptyloctyl, 3-methylpentyl. In addition, the alkyl group may be optionally substituted. The carbons in the alkyl chain may be substituted with other heteroatoms. Among the above, methyl, ethyl, propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl, n-pentyl and neopentyl are preferable.

Cycloalkyl-as used herein, comprises a cyclic alkyl group. Preferred cycloalkyl groups are those containing 4 to 10 ring carbon atoms and include cyclobutyl, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, 4, 4-dimethylcyclohexyl, 1-adamantyl, 2-adamantyl, 1-norbornyl, 2-norbornyl and the like. In addition, the cycloalkyl group may be optionally substituted. The carbon in the ring may be substituted with other heteroatoms.

Alkenyl-as used herein, encompasses both straight and branched chain olefinic groups. Preferred alkenyl groups are those containing 2 to 15 carbon atoms. Examples of the alkenyl group include a vinyl group, an allyl group, a 1-butenyl group, a 2-butenyl group, a 3-butenyl group, a1, 3-butadienyl group, a 1-methylvinyl group, a styryl group, a 2, 2-diphenylvinyl group, a 1-methylallyl group, a1, 1-dimethylallyl group, a 2-methylallyl group, a 1-phenylallyl group, a 3, 3-diphenylallyl group, a1, 2-dimethylallyl group, a 1-phenyl-1-butenyl group and a 3-phenyl-1-butenyl group. In addition, alkenyl groups may be optionally substituted.

Alkynyl-as used herein, straight and branched alkynyl groups are contemplated. Preferred alkynyl groups are those containing 2 to 15 carbon atoms. In addition, alkynyl groups may be optionally substituted.

Aryl or aromatic-as used herein, encompasses both non-fused and fused systems. Preferred aryl groups are those containing from 6 to 60 carbon atoms, more preferably from 6 to 20 carbon atoms, and even more preferably from 6 to 12 carbon atoms. Examples of aryl groups include phenyl, biphenyl, terphenyl, triphenylene, tetraphenylene, naphthalene, anthracene, phenalene, phenanthrene, fluorene, pyrene, chicory, perylene and azulene, preferably phenyl, biphenyl, terphenyl, triphenylene, fluorene and naphthalene. In addition, the aryl group may be optionally substituted. 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-triphenyl-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 '-methyldiphenyl, 4' -tert-butyl-p-terphenyl-4-yl, o-cumyl, m-cumyl, p-cumyl, 2, 3-xylyl, 3, 4-xylyl, 2, 5-xylyl, mesityl and m-quaterphenyl.

Heterocyclyl or heterocyclic-as used herein, encompasses aromatic and non-aromatic cyclic groups. Heteroaryl also refers to heteroaryl. Preferred non-aromatic heterocyclic groups are those containing 3 to 7 ring atoms, which include at least one heteroatom such as nitrogen, oxygen and sulfur. The heterocyclic group may also be an aromatic heterocyclic group having at least one hetero atom selected from a nitrogen atom, an oxygen atom, a sulfur atom and a selenium atom.

Heteroaryl-as used herein, encompasses non-fused and fused heteroaromatic groups that may contain 1 to 5 heteroatoms. Preferred heteroaryl groups are those containing from 3 to 30 carbon atoms, more preferably from 3 to 20 carbon atoms, more preferably from 3 to 12 carbon atoms. Suitable heteroaryl groups include dibenzothiophene, dibenzofuran, dibenzoselenophene, furan, thiophene, benzofuran, benzothiophene, benzoselenophene, carbazole, indolocarbazole, pyridine indole, pyrrolopyridine, pyrazole, imidazole, triazole, oxazole, thiazole, oxadiazole, bisoxazole, thiadiazole, pyridine, pyridazine, pyrimidine, pyrazine, triazine, oxazine, oxathiazine, oxadiazine, indoline, benzimidazole, indazole, indenozine, benzoxazole, benzisoxazole, benzothiazole, quinoline, isoquinoline, cinnoline, quinazoline, quinoxaline, naphthyridine, phthalazine, pteridine, xanthene, acridine, phenazine, phenothiazine, benzothienopyridine, thienobipyridine, benzothiophenopyridine, cinnolinopyrimidine, selenobenzodipyridine, selenobenzene, preferably dibenzothiophene, dibenzofuran, dibenzoselenophene, carbazole, indolocarbazole, imidazole, pyridine, triazine, benzimidazole, 1, 2-azaborine, 1, 3-azaborine, 1, 4-azaborine, borazole, and aza analogues thereof. In addition, the heteroaryl group may be optionally substituted.

Alkoxy-is represented by-O-alkyl. Examples and preferred examples of the alkyl group are the same as those described above. Examples of the alkoxy group having 1 to 20 carbon atoms, preferably 1 to 6 carbon atoms include methoxy, ethoxy, propoxy, butoxy, pentyloxy and hexyloxy. The alkoxy group having 3 or more carbon atoms may be linear, cyclic or branched.

Aryloxy-is represented by-O-aryl or-O-heteroaryl. Examples and preferred examples of aryl and heteroaryl groups are the same as described above. Examples of the aryloxy group having 6 to 40 carbon atoms include a phenoxy group and a biphenyloxy group.

Aralkyl-as used herein, an alkyl group having an aryl substituent. In addition, the aralkyl group may be optionally substituted. Examples of the aralkyl group include benzyl, 1-phenylethyl, 2-phenylethyl, 1-phenylisopropyl, 2-phenylisopropyl, phenyl tert-butyl, α -naphthylmethyl, 1- α -naphthylethyl, 2- α -naphthylethyl, 1- α -naphthylisopropyl, 2- α -naphthylisopropyl, β -naphthylmethyl, 1- β -naphthylethyl, 2- β -naphthylethyl, 1- β -naphthylisopropyl, 2- β -naphthylisopropyl, p-methylbenzyl, m-methylbenzyl, o-methylbenzyl, p-chlorobenzyl, m-chlorobenzyl, o-chlorobenzyl, p-bromobenzyl, m-bromobenzyl, o-bromobenzyl, p-iodobenzyl, m-iodobenzyl, o-iodobenzyl, p-hydroxybenzyl, m-hydroxybenzyl, o-hydroxybenzyl, p-aminobenzyl, m-aminobenzyl, o-aminobenzyl, p-nitrobenzyl, m-nitrobenzyl, o-nitrobenzyl, p-cyanobenzyl, m-cyanobenzyl, o-cyanobenzyl, 1-2-hydroxy-2-phenylisopropyl and 1-chloro-2-phenylisopropyl. Among the above, benzyl, p-cyanobenzyl, m-cyanobenzyl, o-cyanobenzyl, 1-phenylethyl, 2-phenylethyl, 1-phenylisopropyl and 2-phenylisopropyl are preferable.

The term "aza" in aza-dibenzofuran, aza-dibenzothiophene, etc., means that one or more C-H groups in the corresponding aromatic moiety are replaced by a nitrogen atom. For example, azatriphenylenes include dibenzo [ f, h ] quinoxalines, dibenzo [ f, h ] quinolines, and other analogs having two or more nitrogens in the ring system. Other nitrogen analogs of the above-described aza derivatives may be readily envisioned by one of ordinary skill in the art, and all such analogs are intended to be encompassed within the terms described herein.

In this disclosure, unless otherwise defined, when any one of the terms in the group consisting of: substituted alkyl, substituted cycloalkyl, substituted heteroalkyl, substituted aralkyl, substituted alkoxy, substituted aryloxy, substituted alkenyl, substituted aryl, substituted heteroaryl, substituted alkylsilyl, substituted arylsilyl, substituted amine, substituted acyl, substituted carbonyl, substituted carboxylic acid, substituted ester, substituted sulfinyl, substituted sulfonyl, substituted phosphino, meaning alkyl, cycloalkyl, heteroalkyl, aralkyl, alkoxy, aryloxy, alkenyl, aryl, heteroaryl, alkylsilyl, arylsilyl, amine, acyl, carbonyl, carboxylic acid, ester, sulfinyl, sulfonyl and phosphino, any of which groups may be substituted with one or more moieties selected from deuterium, halogen, unsubstituted alkyl having 1 to 20 carbon atoms, unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, unsubstituted heteroalkyl groups having 1 to 20 carbon atoms, unsubstituted aralkyl groups having 7 to 30 carbon atoms, unsubstituted alkoxy groups having 1 to 20 carbon atoms, unsubstituted aryloxy groups having 6 to 30 carbon atoms, unsubstituted alkenyl groups having 2 to 20 carbon atoms, unsubstituted aryl groups having 6 to 30 carbon atoms, unsubstituted heteroaryl groups having 3 to 30 carbon atoms, unsubstituted silyl groups having 3 to 20 carbon atoms, unsubstituted arylsilyl groups having 6 to 20 carbon atoms, unsubstituted amine groups having 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, nitrile groups, isonitrile groups, thio groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof.

It will be understood that when a molecular fragment is described as a substituent or otherwise attached to another moiety, its name may be written depending on whether it is a fragment (e.g., phenyl, phenylene, naphthyl, dibenzofuranyl) or depending on whether it is an entire molecule (e.g., benzene, naphthalene, dibenzofuran). As used herein, these different ways of specifying substituents or linking fragments are considered to be equivalent.

In the compounds mentioned in the present disclosure, a hydrogen atom may be partially or completely replaced by deuterium. Other atoms such as carbon and nitrogen may also be replaced by their other stable isotopes. Substitution of other stable isotopes in the compounds may be preferred because it enhances the efficiency and stability of the device.

In the compounds mentioned in the present disclosure, polysubstitution is meant to encompass disubstituted substitutions up to the maximum range of available substitutions. When a substituent in a compound mentioned in the present disclosure represents multiple substitution (including di-substitution, tri-substitution, tetra-substitution, etc.), that is, it means that the substituent may exist at a plurality of available substitution positions on its connecting structure, and the substituent existing at each of the plurality of available substitution positions may be the same structure or different structures.

In the compounds mentioned in the present disclosure, adjacent substituents in the compounds cannot be linked to form a ring unless specifically defined, for example, adjacent substituents can be optionally linked to form a ring. In the compounds mentioned in the present disclosure, when adjacent substituents can be optionally linked to form a ring, the ring formed may be monocyclic or polycyclic, and alicyclic, heteroalicyclic, aromatic or heteroaromatic rings. In this expression, adjacent substituents may refer to substituents bonded to the same atom, substituents bonded to carbon atoms directly bonded to each other, or substituents bonded to carbon atoms further away. Preferably, adjacent substituents refer to substituents bonded to the same carbon atom as well as substituents bonded to carbon atoms directly bonded to each other.

The expression that adjacent substituents can optionally be linked to form a ring is also intended to mean that two substituents bonded to the same carbon atom are linked to each other by a chemical bond to form a ring, which can be exemplified by the following formula:

the expression that adjacent substituents can optionally be linked to form a ring is also intended to mean that two substituents bonded to carbon atoms directly bonded to each other are linked to each other by a chemical bond to form a ring, which can be exemplified by the following formula:

further, the expression that adjacent substituents can be optionally connected to form a ring is also intended to be taken to mean that, in the case where one of two substituents bonded to carbon atoms directly bonded to each other represents hydrogen, the second substituent is bonded at a position to which the hydrogen atom is bonded, thereby forming a ring. This is exemplified by the following equation:

according to an embodiment of the present invention, there is disclosed an organic electroluminescent device including:

an anode, a cathode, a anode and a cathode,

a cathode electrode, which is provided with a cathode,

and an organic layer disposed between the anode and the cathode, the organic layer comprising at least a first organic layer and a second organic layer;

in the formula 1, the reaction mixture is,

wherein X is independently selected from NR ', CR "R'", O, S or Se;

when X is CR "R '", R "and R'" can optionally be joined to form a ring;

wherein X_a1To X_a8Each independently is CR₁Or N;

wherein X_a1-X_a8At least one of which is CR₁And said R is₁Is a structure represented by formula 1A:

wherein X_a1-X_a8The rest of R present in₁(i.e., R which is not of the structure represented by formula 1A)₁) Each independently selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted aralkyl groups having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy groups having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy groups having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl groups having 2 to 20 carbon atoms, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine groups having 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, nitriles, isonitriles, thio groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof;

two adjacent substituents R₁Can optionally be linked to form a ring;

in the formula 2, the first step is,

wherein a is a structure represented by formula 2A:

in the formula 2A, the reaction mixture is,

wherein at least one of ring D and ring E is a fused ring system;

wherein R is₂And R_2AEach independently selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted aralkyl groups having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy groups having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy groups having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl groups having 2 to 20 carbon atoms, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine groups having 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, nitriles, isonitriles, thio groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof;

R₂and R_2ACan optionally be linked to form a ring;

in this embodiment, X in formula 1_a1-X_a8At least one (or more) of them is CR₁And X_a1-X_a8In (b) is presentR₁At least one (or one of them) is satisfied with the structure represented by formula 1A. X_a1-X_a8The rest of R present in₁The structure represented by formula 1A is not required to have, and may each be independently selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted aralkyl groups having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy groups having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy groups having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl groups having 2 to 20 carbon atoms, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine groups having 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, nitriles, isonitriles, thio groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof.

According to one embodiment of the invention, the organic layer arranged between the anode and the cathode further comprises at least one light emitting layer.

According to one embodiment of the invention, the light emitting layer comprises at least one host material and at least one dopant material.

According to one embodiment of the invention, the dopant material is selected from a fluorescent light emitting material, a phosphorescent light emitting material or a thermally excited time-delayed fluorescent material.

According to one embodiment of the invention, wherein the emission wavelength of the device is between 300nm-1200 nm.

According to an embodiment of the present invention, wherein the organic layer is further from the anode than the light emitting layer, the organic layer two is further from the anode than the organic layer one.

According to one embodiment of the invention, the thickness of the first organic layer is between 0.1nm and 40nm, and/or the thickness of the second organic layer is between 0.1nm and 50 nm.

According to an embodiment of the present invention, wherein the second organic layer further comprises at least one further material.

According to one embodiment of the present invention, the second organic layer further comprises at least one other material, the other material is a metal complex, and the metal complex comprises a compound represented by formula L_qLigand L of_q：

Formula L_qIn, Y₁，Y₂，Y₃，Y₄，Y₅And Y₆Each independently selected from CR_YOr N; wherein each R_YEach independently selected from hydrogen, deuterium, alkyl, alkoxy, amino, silyl, cyano, halogen, aryl and heteroaryl;

wherein Z is NH, O, S or Se;

according to an embodiment of the invention, wherein the organic layer two further comprises at least one metal complex selected from the group consisting of 8-hydroxyquinoline-lithium, 8-hydroxyquinoline-sodium, 8-hydroxyquinoline-potassium, bis (8-hydroxyquinoline) -beryllium, bis (8-hydroxyquinoline) -magnesium, bis (8-hydroxyquinoline) -calcium, tris (8-hydroxyquinoline) -boron, tris (8-hydroxyquinoline) -aluminum, and tris (8-hydroxyquinoline) -gallium.

According to one embodiment of the invention, wherein R ', R "and R'" in formula 1 are each independently selected from substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, or substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms.

According to one embodiment of the invention, wherein R ', R "and R'" in formula 1 are each independently selected from the group consisting of: biphenyl, terphenyl, naphthyl, phenanthryl, triphenylene, fluorenyl, dibenzofuranyl.

According to an embodiment of the present invention, in the formula 1, the X_a1-X_a8The rest of R present in₁(i.e., R which is not of the structure represented by formula 1A)₁) Each independentlySelected from the group consisting of: hydrogen, deuterium, substituted or unsubstituted aryl group having 6 to 30 carbon atoms.

According to an embodiment of the present invention, in the formula 1, the X_a1-X_a8The rest of R present in₁(i.e., R which is not of the structure represented by formula 1A)₁) Each independently selected from the group consisting of: hydrogen, deuterium, phenyl, biphenyl and terphenyl.

According to one embodiment of the present invention, X in said formula 1_a7Is CR₁And said R is₁Is a structure represented by formula 1A.

According to an embodiment of the present invention, Ar in the formula 1₁And Ar₂Each independently selected from phenyl, biphenyl or terphenyl.

According to an embodiment of the present invention, in the formula 1, Ar is₁And Ar₂At least one of which is biphenyl or terphenyl.

According to one embodiment of the present invention, the compound of the structure represented by formula 1 is selected from the group consisting of:

in this embodiment of the present invention,

respectively represent

The same is true for the representation of other structures in this embodiment.

According to one embodiment of the invention, wherein the hydrogen in all the specific compounds shown in the previous embodiment can be partially or completely substituted by deuterium.

According to one embodiment of the present invention, in the formula 1, L' is a single bond, or is a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 30 carbon atoms.

According to one embodiment of the invention, at least one of ring D and ring E in formula 2A is a fused ring system, and the fused ring system is at least two aryl and/or heteroaryl rings fused together to form a fused ring system comprising at least 10 carbon atoms, or a fused ring system comprising a total of at least 10 carbon and nitrogen atoms.

According to one embodiment of the invention, at least one of ring D and ring E in formula 2A is a fused ring system, and the fused ring system is at least three aryl and/or heteroaryl rings fused together to form a fused ring system comprising at least 14 carbon atoms, or a fused ring system comprising a total of at least 14 carbon atoms and nitrogen atoms.

According to one embodiment of the present invention, a in formula 2 is selected from the group consisting of formula 3 to formula 33:

wherein T is₁To T₂₂Each independently selected from CR_TC, or N;

wherein each R_TEach independently selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted aralkyl groups having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy groups having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy groups having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl groups having 2 to 20 carbon atoms, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine groups having 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, nitriles, isonitriles, thio groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof;

in formulae 3 to 33, adjacent substituents can optionally be linked to form a ring.

In this embodiment, when T₁To T₂₂Is selected from C, this means that L in formula 2 is attached to A through this position.

According to one embodiment of the invention, A in said formula 2 is independently selected from A₁To A₂₉₈Group (d) of (a). A. the₁To A₂₉₈See claim 14 for specific structures of (a).

According to one embodiment of the invention, L in formula 2 is independently selected from the group consisting of a single bond, and formula 34-formula 58:

wherein R is₃，R₄，R₅And R₆Each independently represents mono-, poly-or unsubstituted; when they represent multiple substitutions, adjacent substitutions can optionally be joined to form a ring;

wherein R is₃,R₄,R₅And R₆Each independently selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted aralkyl groups having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy groups having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy groups having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl groups having 2 to 20 carbon atoms, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine groups having 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, nitriles, isonitriles, thio groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof.

According to one embodiment of the invention, L in said formula 2 is independently selected from the group consisting of single bonds L₀And L is₁-L₅₈Group (d) of (a). Wherein L is₁-L₅₈See claim 15 for specific structure of (a).

According to one embodiment of the present invention, B in formula 2 is independently selected from the group consisting of formula 59 to formula 63:

wherein X₁To X₆Each independently selected from CR_xC, O, S, N or NR_x’，

Wherein X₁To X_iIs N, or wherein X is₁To X_iAt least two of (a) are N, or X₁To X_iAt least three of which are N; said X_iCorresponding to the X₁To X₆The largest sequence number among the formulae 59 to 63; for example, for formula 59, the X_iCorresponding to the X₁To X₆X having the largest number in formula 59₃. That is, X in formula 59₁To X₃Is N, or X in formula 59₁To X₃At least two of (a) are N, or X in formula 59₁To X₃Three of which are all N.

Wherein R is₇Each independently represents mono-, poly-or unsubstituted; when they represent multiple substitutions, adjacent substitutions can optionally be joined to form a ring;

wherein R is₇,R_xAnd R_x' each is independently selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted aralkyl groups having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy groups having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy groups having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl groups having 2 to 20 carbon atoms, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine groups having 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups,ester groups, nitriles, isonitriles, thio, sulfinyl, sulfonyl, phosphino, and combinations thereof.

According to one embodiment of the invention, B in said formula 2 is independently selected from the group consisting of B1-B105. Wherein, the specific structure of B1-B105 is shown in claim 16.

According to one embodiment of the invention, the compound has the structure of formula 2, wherein a is selected from the group consisting of a₁-A₂₉₈Each B is independently selected from the group consisting of₁-B₁₀₅Each L is independently selected from the group consisting of L₀-L₅₈Group (d) of (a). A. the₁-A₂₉₈，B₁-B₉₁，L₀-L₅₈See the previous embodiments for specific structures.

According to one embodiment of the present invention, in formula 2, wherein ring D and ring E each independently represent a substituted or unsubstituted aryl or heteroaryl group having a ring atom number of 5 to 40, or wherein ring D and ring E each independently represent a substituted or unsubstituted aryl or heteroaryl group having a ring atom number of 5 to 30, or wherein ring D and ring E each independently represent a substituted or unsubstituted aryl or heteroaryl group having a ring atom number of 5 to 20.

According to an embodiment of the present invention, in formula 2, wherein each L is independently selected from the group consisting of a single bond, a substituted or unsubstituted arylene group having 6 to 50 carbon atoms, a substituted or unsubstituted heteroarylene group having 2 to 50 carbon atoms; or each L is independently selected from the group consisting of a single bond, a substituted or unsubstituted arylene group having 6 to 40 carbon atoms, a substituted or unsubstituted heteroarylene group having 2 to 40 carbon atoms; each L is independently selected from the group consisting of a single bond, a substituted or unsubstituted arylene group having 6 to 30 carbon atoms, a substituted or unsubstituted heteroarylene group having 2 to 30 carbon atoms; each L is independently selected from the group consisting of a single bond, a substituted or unsubstituted arylene group having 6 to 20 carbon atoms, and a substituted or unsubstituted heteroarylene group having 2 to 20 carbon atoms.

According to one embodiment of the present invention, in formula 2, wherein each B is independently selected from a substituted or unsubstituted electron deficient heteroaryl group having 2 to 50 carbon atoms, or each B is independently selected from a substituted or unsubstituted electron deficient heteroaryl group having 2 to 40 carbon atoms, each B is independently selected from a substituted or unsubstituted electron deficient heteroaryl group having 2 to 30 carbon atoms, and each B is independently selected from a substituted or unsubstituted electron deficient heteroaryl group having 2 to 20 carbon atoms.

According to one embodiment of the invention, the substituent R in formula 2A₂And R_2AAre not connected to form a ring.

In the structures represented by formulas 3 to 33, T is₅And T₆Are not connected to form a ring.

According to another embodiment of the present invention, a display assembly is also disclosed, which includes an organic electroluminescent device. The specific structure of the organic electroluminescent device is shown in any one of the above embodiments.

In combination with other materials

The materials described herein for use in particular layers in an organic light emitting device may be used in combination with various other materials present in the device. Combinations of these materials are described in detail in U.S. patent application Ser. No. 0132-0161 of U.S. 2016/0359122A1, the entire contents of which are incorporated herein by reference. The materials described or referenced therein are non-limiting examples of materials that may be used in combination with the materials disclosed herein, and one skilled in the art can readily review the literature to identify other materials that may be used in combination.

Materials described herein as being useful for particular layers in an organic light emitting device can be used in combination with a variety of other materials present in the device. For example, the electron transport layers and hole blocking layers disclosed herein are used in combination with other various transport layers, light emitting layers, blocking layers, injection layers, electrodes, and other layers that may be present. Combinations of these materials are described in detail in U.S. patent application Ser. No. US2015/0349273A1, paragraph 0080-0101, the entire contents of which are incorporated herein by reference. The materials described or referenced therein are non-limiting examples of materials that may be used in combination with the materials disclosed herein, and one skilled in the art can readily review the literature to identify other materials that may be used in combination.

The method of fabricating the organic electroluminescent device is not limited, and the method of fabricating the following examples is only an example and should not be construed as a limitation. The preparation of the following examples can be reasonably modified by those skilled in the art in light of the prior art. For example, the proportion of each material in each organic layer in the organic electroluminescent device is not particularly limited, and those skilled in the art can reasonably select the material within a certain range according to the prior art, for example, in the case of an electron transport layer, the compound having the structure represented by formula 2 may account for 10% to 100% of the total weight of the material; alternatively, the compound having the structure represented by formula 2 may account for 20% to 70%; alternatively, the compound having the structure represented by formula 2 may be present in an amount of 30% to 50%. Illustratively, the thickness of each organic layer in the organic electroluminescent device is not particularly limited, and those skilled in the art can reasonably select the thickness within a certain range according to the prior art, for example, the thickness of the hole blocking layer may be between 0.1nm and 40nm, or may be between 1nm and 30nm, or may be between 2nm and 20 nm. As another example, the thickness of the electron transport layer may be between 0.1nm and 50nm, or may be between 1nm and 45nm, or may be between 5nm and 40 nm. The characteristics of the light emitting devices prepared in the examples were tested using equipment conventional in the art, in a manner well known to those skilled in the art. Since the relevant contents of the above-mentioned device usage, testing method, etc. are known to those skilled in the art, the inherent data of the sample can be obtained with certainty and without being affected, and therefore, the relevant contents are not described in detail in this patent.

Example 1-1: organic electroluminescent devices comprising the material combinations of the invention were prepared.

First, a glass substrate, having an 80nm thick Indium Tin Oxide (ITO) anode, was cleaned and then treated with UV ozone and oxygen plasma. After the treatment, the substrate was dried in a glove box filled with nitrogen gas to remove moisture, and then the substrate was mounted on a substrate holder and loaded into a vacuum chamber. The organic layer specified below was in a vacuum of about 10 degrees^-8In the case of Torr

The rate of (a) was successively evaporated on the ITO anode by thermal vacuum. Compound HI was used as a Hole Injection Layer (HIL) with a thickness of

The compound HT is used as Hole Transport Layer (HTL) with a thickness of

Compound EB was used as an Electron Blocking Layer (EBL) with a thickness of

The compound Host1 as the Host material and the compound D1 as the dopant are co-deposited to be used as the luminescent layer (EML), and the dopant D1 accounts for 4 percent of the total weight of the luminescent layer material and has the thickness of

On top of the EML, compound 2-2-2 was used as a Hole Blocking Layer (HBL) with a thickness of

On HBL, Compound A₃₀L₀B₅₂Co-depositing with compound EI as Electron Transport Layer (ETL), wherein the compound EI accounts for 60% of the total weight of the electron transport layer material, and the thickness of ETL is

Finally, evaporation

The compound EI is used as Electron Injection Layer (EIL) and evaporated

As a cathode. The device was then transferred back to the glove box and encapsulated with a glass lid to complete the device.

Comparative example 1-1: an organic electroluminescent device comprising only the hole-blocking layer compound of the present invention as a hole-blocking layer, while comprising an electron-transporting layer compound not falling within the specific range of the present invention co-deposited with the compound EI as an electron-transporting layer, was prepared by a method different from that of example 1-1 only in that the electron-transporting layer: co-depositing compound ET and compound EI as Electron Transport Layer (ETL), wherein compound EI is 60% of total weight of electron transport layer material, and ETL has thickness of

Comparative examples 1 to 2: an organic electroluminescent device comprising a hole-blocking layer compound, which is outside the specific range of the present invention, as a hole-blocking layer, while comprising an electron-transporting layer compound of the present invention co-deposited with compound EI as an electron-transporting layer, was prepared by a method different from the preparation method of example 1-1 only in that the hole-blocking layer: the compound HB was used as a hole-blocking layer (HBL) with a thickness of

Comparative examples 1 to 3: an organic electroluminescent device comprising a hole-blocking layer compound not falling within the specified range of the present invention as a hole-blocking layer, while an electron-transporting layer compound not falling within the specified range of the present invention was co-deposited with the compound EI as an electron-transporting layer, and the preparation method thereof was different from that of example 1-1 only in that the hole-blocking layer and the electron-transporting layer: the compound HB was used as a hole-blocking layer (HBL) with a thickness of

Co-depositing compound ET and compound EI as Electron Transport Layer (ETL), wherein compound EI is 60% of total weight of electron transport layer material, and ETL has thickness of

Part of the material structures used in the devices are as follows:

the detailed partial device layer structure, and device data of the examples and comparative examples are shown in table 1. Layers of more than one material are used, with different compounds being doped in the stated weight ratios.

TABLE 1

Table 1 shows that electroluminescent devices comprising different hole blocking layers in combination with an electron transport layer have a current density of 10mA/cm²The test results of (1).

From the color coordinates and half-width data of example 1-1 and comparative examples 1-1 to 1-3, it is understood that the use of the hole blocking layer compound of the present invention and the electron transport layer compound of the present invention has little influence on the color change of the device.

From the comparison results between example 1-1 and comparative examples 1-3, it is understood that the voltage of example 1-1 is almost equivalent and the external quantum efficiency is reduced by 1.1%, but the device lifetime LT95 is greatly improved from 292 hours in comparative examples 1-3 to 663 hours in example 1-1 and the lifetime is improved by 127%.

From the comparison results between example 1-1 and comparative example 1-2, it is understood that the voltage of example 1-1 is slightly higher and the external quantum efficiency is reduced by 1.3%, but the device lifetime LT95 is greatly improved from 429 hours of comparative example 1-2 to 663 hours of example 1-1 and the lifetime is improved by 55%.

From the comparison results between example 1-1 and comparative example 1-1, it is understood that the voltage of example 1-1 is almost equivalent, and the external quantum efficiency is slightly decreased by 0.2%, but the device lifetime LT95 is greatly increased from 600 hours in comparative example 1-1 to 663 hours in example 1-1, and the lifetime is increased by 11%.

Therefore, when the hole blocking layer compound of the present invention and the electron transport layer compound of the present invention are used in combination, the lifetime of the device is significantly improved although the external quantum efficiency of the device is slightly reduced, as compared to the case where both compounds are used alone, and the case where the hole blocking layer compound of the present invention and the electron transport layer compound of the present invention having the structure of formula 2 are used in combination, which highlights the advantage of improving the lifetime of the device when the hole blocking layer compound of the present invention having the structure of formula 1 and the electron transport layer compound of the present invention having the structure of formula 2 are used in combination. For OLED devices where long lifetime is desired, a device structure using the hole blocking layer compound of the present invention in combination with the electron transport layer compound of the present invention is highly advantageous.

In summary, the invention discloses an organic electroluminescent device comprising a hole blocking layer of a compound having a structure of formula 1 and an electron transport layer having a structure of formula 2. By using the specific compound combination, the service life of the device can be greatly prolonged, the voltage and the efficiency are better considered, the comprehensive performance of the device is obviously improved, and the device has more advantages in the commercial application field.

It should be understood that the various embodiments described herein are illustrative only and are not intended to limit the scope of the invention. Thus, the invention as claimed may include variations from the specific embodiments and preferred embodiments described herein, as will be apparent to those skilled in the art. Many of the materials and structures described herein may be substituted with other materials and structures without departing from the spirit of the present invention. It should be understood that various theories as to why the invention works are not intended to be limiting.

Claims

1. An organic electroluminescent device comprising:

an anode, a cathode, a anode and a cathode,

a cathode electrode, which is provided with a cathode,

in the formula 1, the reaction mixture is,

wherein X is independently selected from NR ', CR "R'", O, S or Se;

when X is selected from CR "R '", R "and R'" can optionally be joined to form a ring;

wherein X_a1To X_a8Each independently selected from CR₁Or N; wherein X_a1-X_a8At least one of which is CR₁And R is₁Is a structure represented by formula 1A:

wherein L' is selected from a single bond, a substituted or unsubstituted arylene group having 6 to 60 carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 60 carbon atoms;

wherein X_a1-X_a8The rest of R present in₁Each independently selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted aralkyl groups having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy groups having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy groups having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl groups having 2 to 20 carbon atoms, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine groups having 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, nitriles, isonitriles, thio groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof;

two adjacent substituents R₁Can optionally be linked to form a ring;

in the formula 2, the first step is,

wherein n is selected from 1,2, 3 or 4; when n is 2 or more, each group L and B may be the same or different;

wherein L is selected from a single bond, a substituted or unsubstituted arylene group having 6 to 60 carbon atoms, or a substituted or unsubstituted heteroarylene group having 2 to 60 carbon atoms;

wherein a has a structure represented by formula 2A:

in the formula 2A, the reaction mixture is,

wherein at least one of ring D and ring E is a fused ring system;

R₂and R_2ACan optionally be linked to form a ring.

2. The device of claim 1, the organic layer disposed between the anode and the cathode further comprising at least one light emitting layer; preferably, the light emitting layer comprises at least one host material and at least one dopant material.

3. The device of claim 2, wherein the organic layer is further from the anode than the light emitting layer, and the organic layer two is further from the anode than the organic layer one.

4. The device of claim 1, wherein the device has an emission wavelength between 300nm-1200 nm.

5. The device of claim 1, wherein the first organic layer has a thickness between 0.1nm and 40nm, and/or the second organic layer has a thickness between 0.1nm and 50 nm.

6. The device of claim 1, wherein the second organic layer further comprises at least one other material;

preferably, the other material is a metal complex, and the metal complex comprises a compound represented by formula L_qLigand L of_q：

wherein Z is selected from N, O, S or Se;

preferably, wherein the metal complex is 8-hydroxyquinoline-lithium, 8-hydroxyquinoline-sodium, 8-hydroxyquinoline-potassium, bis (8-hydroxyquinoline) -beryllium, bis (8-hydroxyquinoline) -magnesium, bis (8-hydroxyquinoline) -calcium, tris (8-hydroxyquinoline) -boron, tris (8-hydroxyquinoline) -aluminum, or tris (8-hydroxyquinoline) -gallium.

7. The device of claim 1, wherein R ', R ", and R'" in formula 1 are each independently selected from a substituted or unsubstituted aryl group having 6-30 carbon atoms, or a substituted or unsubstituted heteroaryl group having 3-30 carbon atoms; preferably, R ', R "and R'" are each independently selected from the group consisting of: biphenyl, terphenyl, naphthyl, phenanthryl, triphenylene, fluorenyl, dibenzofuranyl.

8. The device of claim 1, X in said formula 1_a1-X_a8The rest of R present in₁Each independently selected from the group consisting of: hydrogen, deuterium, substituted or unsubstituted aryl group having 6 to 30 carbon atoms; preferably, X_a1-X_a8The rest of R present in₁Each independently selected from the group consisting of: hydrogen, deuterium, phenyl, biphenyl and terphenyl.

9. The device of claim 1, X in said formula 1_a7Is CR₁And said R is₁Is a structure represented by formula 1A.

10. The device of claim 1 or 9, Ar in formula 1₁And Ar₂Each independently selected from phenyl, biphenyl or terphenyl; preferably, Ar is₁And Ar₂At least one of which is biphenyl or terphenyl.

11. The device of claim 1, wherein the compound of the structure of formula 1 is selected from the group consisting of:

12. the device of claim 11, wherein the hydrogen in all particular compounds from compound 1-1-1 to compound 20-10-4 can be partially or fully substituted with deuterium.

13. The device of claim 1, wherein at least one of ring D and ring E in formula 2A is a fused ring system, and the fused ring system is at least two aryl and/or heteroaryl rings fused together to form a fused ring system comprising at least 10 carbon atoms, or a fused ring system comprising a total of at least 10 carbon atoms and nitrogen atoms;

alternatively, at least one of ring D and ring E in formula 2A is a fused ring system, and the fused ring system is at least three aryl and/or heteroaryl rings fused together to form a fused ring system comprising at least 14 carbon atoms, or a fused ring system comprising a total of at least 14 carbon atoms and nitrogen atoms.

14. The device of claim 1, a in formula 2 is selected from the group consisting of formula 3 to formula 33:

wherein T is₁To T₂₂Each independently selected from CR_TC, or N;

wherein each R_TEach independently selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl groups having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted aralkyl groups having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy groups having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy groups having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl groups having 2 to 20 carbon atoms, substituted or unsubstituted aryl groups having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl groups having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl groups having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl groups having 6 to 20 carbon atoms, substituted or unsubstituted amine groups having from 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, nitriles, isonitriles, thio groups, sulfinyl groups, sulfonyl groups,a phosphine group, and combinations thereof; in formulae 3 to 33, adjacent substituents can optionally be linked to form a ring;

preferably, said A is independently selected from A₁-A₂₉₈Group consisting of:

15. the device of claim 1 or 14, wherein L in formula 2 is selected from the group consisting of a single bond and formulae 34 to 58:

wherein R is₃,R₄,R₅And R₆Each independently represents mono-, poly-or unsubstituted; when they represent multiple substitutions, adjacent substitutions can optionally be joined to form a ring;

wherein R is₃,R₄,R₅And R₆Each independently selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl having 1 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 ring carbon atoms, substituted or unsubstituted heteroalkyl having 1 to 20 carbon atoms, substituted or unsubstituted aralkyl having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl having 2 to 20 carbon atoms, substituted or unsubstituted aryl having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl having 3 to 20 carbon atoms, substituted or unsubstituted alkyl having 6 to 20 carbon atoms, substituted or unsubstituted cycloalkyl having 3 to 20 carbon atoms, or substituted cycloalkyl having 3 to 20 carbon atomsSubstituted or unsubstituted amine groups having 0 to 20 carbon atoms, acyl groups, carbonyl groups, carboxylic acid groups, ester groups, nitriles, isonitriles, thio groups, sulfinyl groups, sulfonyl groups, phosphino groups, and combinations thereof;

preferably, each L is independently selected from the group consisting of single bond L₀And L is₁To L₅₈Group consisting of:

16. the device of claim 1 or 15, wherein B in formula 2 is selected from the group consisting of formula 59 to formula 63:

Wherein X₁To X_iIs N, or wherein X is₁To X_iAt least two of (a) are N, or X₁To X_iAt least three of which are N; said X_iCorresponding to the X₁To X₆The largest sequence number among formulae 59 to 63;

wherein R is₇,R_xAnd R_x' each is independently selected from the group consisting of: hydrogen, deuterium, halogen, substituted or unsubstituted alkyl groups having 1 to 20 carbon atoms, substituted or unsubstituted alkyl groups having 3 to 20 ring carbon atomsSubstituted or unsubstituted heteroalkyl group having 1 to 20 carbon atoms, substituted or unsubstituted aralkyl group having 7 to 30 carbon atoms, substituted or unsubstituted alkoxy group having 1 to 20 carbon atoms, substituted or unsubstituted aryloxy group having 6 to 30 carbon atoms, substituted or unsubstituted alkenyl group having 2 to 20 carbon atoms, substituted or unsubstituted aryl group having 6 to 30 carbon atoms, substituted or unsubstituted heteroaryl group having 3 to 30 carbon atoms, substituted or unsubstituted alkylsilyl group having 3 to 20 carbon atoms, substituted or unsubstituted arylsilyl group having 6 to 20 carbon atoms, substituted or unsubstituted amine group having 0 to 20 carbon atoms, acyl group, carbonyl group, carboxylic acid group, ester group, nitrile, isonitrile, thio group, sulfinyl group, sulfonyl, phosphino, and combinations thereof;

preferably, each B is independently selected from the group consisting of B1 to B105:

17. the device of claim 16, wherein the compound of the structure of formula 2, wherein a is selected from the group consisting of a₁-A₂₉₈Each B is independently selected from the group consisting of₁-B₁₀₅Each L is independently selected from the group consisting of L₀-L₅₈Group (d) of (a).

18. A display assembly comprising the organic electroluminescent device of any one of claims 1 to 17.