Compound, composition, hole transport layer, quantum dot layer, light-emitting element, panel and device

Abstract

The present invention belongs to the technical field of display. Disclosed are a photosensitive compound, a material composition, a hole transport layer, a quantum dot layer, a light-emitting element, a display panel and a display device. The photosensitive compound comprises a parent core structure having hole transport capability and a plurality of cross-linked side chains connected to the parent core structure, and can be cross-linked with a hole transport material under illumination when being applied to a material composition. The photosensitive compound can improve the performance of the hole transport layer.

Description

Compounds, compositions, hole transport layers, quantum dot layers, light-emitting elements, panels, and devices Technical Field

[0001] This disclosure relates to the field of display technology, and more specifically, to a photosensitive compound, a material composition, a hole transport layer, a quantum dot layer, a light-emitting element, a display panel, and a display device. Background Technology

[0002] Thin-film photoelectric conversion devices, such as OLEDs (organic light-emitting diodes), QLEDs (quantum dot light-emitting diodes), and organic photoelectric converters, are increasingly widely used. In the fabrication of thin-film photoelectric conversion devices, the hole transport layer can be prepared using a solution method.

[0003] It should be noted that the information disclosed in the background section above is only used to enhance the understanding of the background of this disclosure, and therefore may include information that does not constitute prior art known to those skilled in the art. Summary of the Invention

[0004] The purpose of this disclosure is to overcome the shortcomings of the prior art and provide a photosensitive compound, a material composition, a hole transport layer, a light-emitting element, a light-emitting panel, and a display device to improve the performance of the hole transport layer.

[0005] According to one aspect of this disclosure, a photosensitive compound is provided, wherein the structural formula of the photosensitive compound is shown in Chemical Formula 1:

[0006] Wherein, A is a core structure with hole transport capability;

[0007] n is a positive integer selected from 2 to 10;

[0008] L a Each occurrence is independently selected from single bond, O, S, N(R1), CH2-N(R1), C(R1)=N, C(O)O, or C(O)N(R1);

[0009] L b Each occurrence is independently selected from single bonds or flexible connecting chains with 1 to 20 carbon atoms;

[0010] L c Each occurrence is independently selected from single bonds, O, S, N(R2), CH2-N(R2), C(R2)=N, C(O)O, or C(O)N(R2);

[0011] Each time L appears a L b and L cNot both are single keys;

[0012] Each time R1 appears, it is independently selected from hydrogen, deuterium, substituted or unsubstituted alkyl groups with 1 to 10 carbon atoms, substituted or unsubstituted cycloalkyl groups with 5 to 10 carbon atoms, substituted or unsubstituted aryl groups with 6 to 18 carbon atoms, and substituted or unsubstituted heteroaryl groups with 5 to 18 carbon atoms.

[0013] Each time R2 appears, it is independently selected from hydrogen, deuterium, substituted or unsubstituted alkyl groups with 1 to 10 carbon atoms, substituted or unsubstituted cycloalkyl groups with 5 to 10 carbon atoms, substituted or unsubstituted aryl groups with 6 to 18 carbon atoms, and substituted or unsubstituted heteroaryl groups with 5 to 18 carbon atoms.

[0014] Ar1 is selected independently each time it appears from aryl groups with 6 to 12 substituted or unsubstituted carbon atoms, or heteroaryl groups with 5 to 12 substituted or unsubstituted carbon atoms.

[0015] According to a second aspect of this disclosure, a material composition is provided, wherein the material composition comprises a hole transport material and the aforementioned photosensitive compound; the photosensitive compound is capable of crosslinking with the hole transport material under light irradiation.

[0016] According to a third aspect of this disclosure, a hole transport layer is provided, wherein the hole transport layer is prepared using the above-described material composition.

[0017] According to a fourth aspect of this disclosure, a material composition is provided, wherein the material composition comprises a ligand-modified quantum dot material and the above-described photosensitive compound; the photosensitive compound is capable of crosslinking with the ligand under light irradiation.

[0018] According to a fifth aspect of this disclosure, a quantum dot layer is provided, wherein the quantum dot layer is prepared using the above-described material composition.

[0019] According to a sixth aspect of this disclosure, a light-emitting element is provided, comprising an anode, a hole transport layer, a light-emitting layer, and a cathode arranged in sequence.

[0020] Wherein, the hole transport layer of the light-emitting element is the hole transport layer described above; and / or, the light-emitting layer of the light-emitting element is the quantum dot layer described above.

[0021] According to a seventh aspect of this disclosure, a light-emitting panel is provided, comprising an array of the aforementioned light-emitting elements; wherein a gap is provided between the hole transport layers of at least two adjacent light-emitting elements.

[0022] According to the eighth aspect of this disclosure, a display device is provided, including the above-described light-emitting panel.

[0023] It should be understood that the above general description and the following detailed description are exemplary and explanatory only, and are not intended to limit this disclosure. Attached Figure Description

[0024] The accompanying drawings, which are incorporated in and form part of this specification, illustrate embodiments consistent with this disclosure and, together with the description, serve to explain the principles of this disclosure. It is obvious that the drawings described below are merely some embodiments of this disclosure, and those skilled in the art can obtain other drawings based on these drawings without any inventive effort.

[0025] Figure 1 is a schematic diagram of the structure of a quantum dot light-emitting diode in one embodiment of this disclosure.

[0026] Figure 2 shows the performance test results of quantum dot light-emitting diodes when compounds 1 and 2 are used to prepare hole transport layers in one embodiment of this disclosure.

[0027] Figure 3 shows the performance test results of quantum dot light-emitting diodes when compounds 3 and 4 are used to prepare hole transport layers in one embodiment of this disclosure. Detailed Implementation

[0028] Exemplary embodiments will now be described more fully with reference to the accompanying drawings. However, these exemplary embodiments can be implemented in many forms and should not be construed as limited to the embodiments set forth herein; rather, they are provided so that this disclosure will be thorough and complete, and will fully convey the concept of the exemplary embodiments to those skilled in the art. The same reference numerals in the drawings denote the same or similar structures, and therefore detailed descriptions of them will be omitted. Furthermore, the drawings are merely illustrative of this disclosure and are not necessarily drawn to scale.

[0029] The terms “a,” “one,” “the,” “the,” and “at least one” are used to indicate the presence of one or more elements / components / etc.; the terms “including” and “having” are used to indicate an open-ended inclusion and to mean that there may be other elements / components / etc. in addition to the listed elements / components / etc.; the terms “first,” “second,” and “third,” etc., are used only as markers and are not a limitation on the number of objects.

[0030] In this disclosure, the term "substituted or unsubstituted" means that the functional group described after the term may or may not have substituents (hereinafter, for ease of description, substituents are collectively referred to as Rc). For example, "substituted or unsubstituted aryl" refers to an aryl group having a substituent Rc or an unsubstituted aryl group. The substituent Rc mentioned above can be, for example, deuterium, halogen groups, cyano, alkyl, alkoxy, alkylthio, haloalkyl, deuteralkyl, cycloalkyl, trialkylsilyl, triphenylsilyl, diarylphosphine oxide, aryloxy, etc. In this disclosure, the "substituted" functional group can be substituted by one or more of the aforementioned substituents Rc.

[0031] In embodiments of this disclosure, the number of carbon atoms in substituted or unsubstituted groups refers to the total number of carbon atoms. For example, if Ar1 is a substituted aryl group with 12 carbon atoms, then the total number of carbon atoms in the aryl group and its substituents is 12.

[0032] The descriptive phrases used in this disclosure, such as "...each independently selected" and "...independently selected each time it appears," can mean that the specific options expressed by the same symbol in different groups do not affect each other, or that the specific options expressed by the same symbol in the same group do not affect each other. For example: in " In this context, each q is independently 0, 1, 2, or 3, and each R is independently selected from the descriptions of hydrogen, fluorine, and chlorine. The meaning is as follows: Formula Q-1 indicates that there are q substituents R on the benzene ring. Each R can be the same or different, and the options for each R do not affect each other. Formula Q-2 indicates that there are q substituents R on each benzene ring of biphenyl. The number q of substituents R on the two benzene rings can be the same or different, and each R can be the same or different. The options for each R do not affect each other.

[0033] In this disclosure, aryl refers to any optional functional group or substituent derived from an aromatic hydrocarbon ring. The aryl group can be a monocyclic aryl (e.g., phenyl) or a polycyclic aryl; in other words, the aryl group can be a monocyclic aryl, a fused-ring aryl, two or more monocyclic aryl groups conjugated by carbon-carbon bonds, a monocyclic aryl and a fused-ring aryl group conjugated by carbon-carbon bonds, or two or more fused-ring aryl groups conjugated by carbon-carbon bonds. That is, two or more aromatic groups conjugated by carbon-carbon bonds can also be considered as aryl groups in this disclosure. Fused-ring aryl groups may include, for example, bicyclic fused aryl (e.g., naphthyl), tricyclic fused aryl (e.g., phenanthrene, fluorenyl, anthracene), etc. The aryl group does not contain heteroatoms such as B, N, O, S, Se, Si, or P. For example, in this disclosure, biphenyl, terphenyl, etc., are aryl groups. Examples of aryl groups may include phenyl, naphthyl, fluorenyl, anthracene, phenanthryl, biphenyl, terphenyl, tetraphenyl, benzo[9,10]phenanthryl, pyrene, benzofluoranthracene, etc. Indene, etc., but not limited to these.

[0034] In embodiments of this disclosure, the substituted aryl group may be one or more hydrogen atoms of the aryl group that are replaced by groups such as deuterium atoms, halogen groups, -CN, aryl, heteroaryl, trialkylsilyl, alkyl, cycloalkyl, alkoxy, alkylthioyl, etc. Specific examples of heteroaryl-substituted aryl groups include, but are not limited to, dibenzofuranyl-substituted phenyl, dibenzothiopheneyl-substituted phenyl, pyridyl-substituted phenyl, carbazoleyl-substituted phenyl, etc. It should be understood that the number of carbon atoms in the substituted aryl group refers to the total number of carbon atoms of the aryl group and the substituents on the aryl group. For example, a substituted aryl group with 18 carbon atoms means that the total number of carbon atoms of the aryl group and the substituents is 18.

[0035] In embodiments of this disclosure, a heteroaryl group refers to a monovalent aromatic ring or its derivative containing at least one heteroatom, where the heteroatom can be at least one of B, O, N, P, Si, Se, and S. The heteroaryl group can be a monocyclic or polycyclic heteroaryl group; in other words, it can be a single aromatic ring system or a system of multiple aromatic rings conjugated by carbon-carbon bonds, and any aromatic ring system can be a single aromatic monocyclic ring or a fused aromatic ring. For example, heteroaryl groups may include thiophene, furanyl, pyrrole, imidazolyl, thiazolyl, oxazolyl, oxadiazolyl, triazolyl, pyridyl, bipyridyl, pyrimidinyl, triazinyl, acridinel, pyridazinyl, pyrazinyl, quinolinyl, quinazolinyl, quinoxolinyl, phenoxazinyl, phthalazinyl, pyridopyrimidinyl, pyridopyrazinyl, isoquinolinyl, indolyl, carbazole, benzoxazolyl, and benzimidazole. The group includes, but is not limited to, benzothiazolyl, benzocarbazolyl, benzothiophenel, dibenzothiophenel, thienozothiophenel, benzofuranyl, phenanthrolinel, isoxazolyl, thiadiazolyl, benzothiazolyl, phenothiazinyl, silanyl, dibenzofuranyl, and N-arylcarbazolyl (such as N-phenylcarbazolyl), N-heteroarylcarbazolyl (such as N-pyridylcarbazolyl), and N-alkylcarbazolyl (such as N-methylcarbazolyl), etc. Among these, thiophenel, furanyl, and phenanthrolinel are heteroaryl groups of the single aromatic ring type, while N-arylcarbazolyl and N-heteroarylcarbazolyl are heteroaryl groups of the polycyclic system type linked by carbon-carbon conjugation.

[0036] In embodiments of this disclosure, the substituted heteroaryl group may be one or more hydrogen atoms of the heteroaryl group that are replaced by groups such as deuterium atoms, halogen groups, -CN, aryl, heteroaryl, trialkylsilyl, alkyl, cycloalkyl, alkoxy, alkylthioyl, etc. Specific examples of aryl-substituted heteroaryl groups include, but are not limited to, phenyl-substituted dibenzofuranyl, phenyl-substituted dibenzothiophenyl, phenyl-substituted pyridyl, etc. It should be understood that the number of carbon atoms in the substituted heteroaryl group refers to the total number of carbon atoms of the heteroaryl group and the substituents on the heteroaryl group.

[0037] In this embodiment of the disclosure, a non-positioned connecting key refers to a single bond extending from the ring system. This means that one end of the linking bond can connect to any position in the ring system that the bond passes through, and the other end connects to the rest of the compound molecule.

[0038] For example, as shown in equation (f) below, the naphthyl group represented by equation (f) is connected to other positions in the molecule through two non-positional linkages that span the bicyclic ring. This means that any possible connection mode is shown in equations (f-1) to (f-10).

[0039] For another example, as shown in equation (X'), the phenanthrene group represented by equation (X') is connected to other positions in the molecule via a non-positional linker extending from the middle of one side of the benzene ring. This means that any possible connection mode shown in equations (X'-1) to (X'-4) is included.

[0040] In the embodiments of this disclosure, a non-positional substituent refers to a substituent connected by a single bond extending from the center of the ring system, indicating that the substituent can be attached to any possible position in the ring system. For example, as shown in the following formula (Y), the substituent R' group represented by formula (Y) is connected to the quinoline ring by a non-positional linking bond, which means that it includes any possible connection mode shown in formulas (Y-1) to (Y-7).

[0041] Thin-film photoelectric conversion elements are increasingly widely used. For example, thin-film light-emitting elements are widely used in lighting and display fields, while thin-film power-generating elements are widely used in solar cells and photoelectric detection fields. A thin-film photoelectric conversion element generally includes two opposing electrodes, and a hole transport layer, a photoelectric conversion layer, and an electron transport layer stacked sequentially between the two electrodes.

[0042] In the field of thin-film photoelectric conversion element fabrication, solution processing is an important film-forming process. In related technologies, a hole transport layer can be prepared using a film-forming solution containing a hole transport material and a crosslinking agent; during film formation, the hole transport material and the crosslinking agent crosslink. However, the inventors discovered in practice that the performance of the hole transport layer formed after the hole transport material and crosslinking agent crosslink is not as expected, especially its hole transport capacity is weaker than that of the film formed without the addition of a crosslinking agent. Through inspection and testing, the inventors found that the crosslinking agent may disrupt the hole transport path of the hole transport material during the reaction process, leading to a decrease in the hole mobility of the formed hole transport layer. Taking QLED as an example of a thin-film photoelectric conversion element, if a crosslinking agent is added during the preparation of the QLED's hole transport layer, its performance is lower compared to a QLED without a crosslinking agent in the hole transport layer.

[0043] In related technologies, quantum dot layers can be created by reacting ligand-modified quantum dot materials with crosslinking agents, thereby crosslinking the quantum dot materials. However, the organic material formed by the ligands and crosslinking agents restricts hole transport within the quantum dot layer, leading to carrier imbalance and hindering improvements in luminescence efficiency and lifetime. Therefore, this disclosure provides a photosensitive compound that can be used in the preparation of both hole transport layers and quantum dot layers.

[0044] In a first application scenario, a first material composition for forming a hole transport layer can be provided. This first material composition includes a hole transport material and a photosensitive compound, the photosensitive compound being crosslinkable with the hole transport material under light irradiation. In this first material composition, the photosensitive compound acts as a crosslinking agent, reacting with the hole transport material to enable the first material composition to form a hole transport layer. In some embodiments, the first material composition can be a liquid (e.g., an ink or adhesive for forming a hole transport layer). In addition to the hole transport material and the photosensitive compound, the liquid may also include other necessary auxiliary components, such as a solvent.

[0045] In some embodiments, the first material composition can be ink for inkjet printing. Thus, the hole transport layer can be prepared using inkjet printing. For example, after printing the ink into a predetermined area (e.g., a pixel opening), the photosensitive compound therein can be cross-linked with the hole transport material by light irradiation, thereby forming the hole transport layer. When subsequent film layers (e.g., quantum dot layers) are prepared using a solution method, the solvent of the subsequent film layers will have difficulty dissolving the hole transport layer. This facilitates the preparation of subsequent film layers.

[0046] In some embodiments, the first material composition can be an adhesive, such as an adhesive for coating or screen printing. The adhesive can be used to form the desired adhesive layer through processes such as spin coating or printing. Light exposure can be used to crosslink the photosensitive compound in the adhesive layer with the hole transport material, thereby forming a hole transport layer. Similarly, because the hole transport material and the photosensitive compound are crosslinked, the hole transport layer will not be dissolved in subsequent film preparation processes, thus facilitating the preparation of subsequent film layers.

[0047] In other embodiments of this disclosure, the first material composition can also be a patternable photosensitive adhesive; the adhesive layer formed by the first material composition can be patterned by exposure and development, that is, the first material composition can be used in photolithography to form a patterned hole transport layer. For example, the adhesive layer formed by the first material composition can be exposed and developed; in the light-irradiated areas, the hole transport material crosslinks with the photosensitive compound, resulting in reduced solubility, and therefore can be retained during development; in the un-light-irradiated areas, the hole transport material fails to crosslink with the photosensitive compound, and therefore can be washed away during development. When the first material composition is used to form a display panel containing light-emitting elements, the limitation of the printing process on resolution can be eliminated, and the formation of a patterned hole transport layer through photolithography can be facilitated, thereby improving the resolution of the display panel.

[0048] In this embodiment of the present disclosure, the photosensitive compound in the first material composition is a compound with high hole mobility. When the photosensitive compound is cross-linked with the hole transport material, it still has a high hole mobility. Therefore, even if some of the hole transport material is damaged during the cross-linking process, resulting in a decrease in hole transport performance, the high hole mobility of the structure formed by the photosensitive compound itself can compensate for the decrease in hole transport capability of some of the hole transport material, thereby ensuring that the hole transport capability of the hole transport layer does not decrease due to the addition of the photosensitive compound.

[0049] In a second application scenario, a second material composition for forming a quantum dot layer can be provided. This second material composition includes a ligand-modified quantum dot material and a photosensitive compound, which is capable of crosslinking with ligands in the ligand-modified quantum dot material under light irradiation. In this second material composition, the photosensitive compound acts as a crosslinking agent, reacting with the ligands to enable the material composition to form a quantum dot layer. In some embodiments, the second material composition can be a liquid (e.g., an ink or adhesive for forming a quantum dot layer), which, in addition to including the ligand-modified quantum dot material and the photosensitive compound, may also include other necessary auxiliary components, such as a solvent.

[0050] In some embodiments, the second material composition can be ink for inkjet printing. Thus, the quantum dot layer can be prepared using inkjet printing. For example, after printing the ink into a predetermined area (e.g., a pixel opening), the photosensitive compound and ligands can be cross-linked by light to form the quantum dot layer. When subsequent film layers (e.g., electron transport layers) are prepared using a solution method, the solvent of the subsequent film layer will have difficulty dissolving the quantum dot layer. This facilitates the preparation of subsequent film layers.

[0051] In some embodiments, the second material composition can be an adhesive, such as an adhesive for coating or screen printing. This adhesive can be used to form the desired adhesive layer through processes such as spin coating or printing. Light exposure can then be used to crosslink the photosensitive compound and ligands in the adhesive layer, thereby forming a quantum dot layer. Similarly, because the ligands and photosensitive compound are crosslinked, the quantum dot layer will not dissolve during subsequent film preparation processes, thus facilitating the preparation of subsequent film layers.

[0052] In other embodiments of this disclosure, the second material composition can also be a patternable photosensitive adhesive; the adhesive layer formed by the second material composition can be patterned by exposure and development, that is, the second material composition can be used in photolithography to form a patterned quantum dot layer. For example, the adhesive layer formed by the material composition can be exposed and developed; in the light-irradiated areas, the ligand-modified quantum dot material crosslinks with the photosensitive compound, resulting in reduced solubility, and therefore can be retained during development; in the un-light-irradiated areas, the ligand-modified quantum dot material fails to crosslink with the photosensitive compound, and therefore can be washed away during development. When this second material composition is used to form a display panel containing light-emitting elements, the limitation of the printing process on resolution can be eliminated, and the formation of a patterned quantum dot layer through photolithography can be facilitated, thereby improving the resolution of the display panel.

[0053] In this embodiment, the photosensitive compound in the second material composition is a compound with high hole mobility; even after the photosensitive compound is cross-linked with the ligand-modified quantum dot material, it still maintains a high hole mobility. Therefore, the organic structure formed by the photosensitive compound and the ligand has high hole mobility, which facilitates hole injection into the quantum dot layer, improves the electron-hole balance in the quantum dot layer, and improves the luminous efficiency of the quantum dot layer; at the same time, it also helps to reduce hole accumulation in the hole transport layer, thus improving the lifespan of the light-emitting element and the display panel. In one embodiment of this disclosure, the structural formula of the photosensitive compound provided in this disclosure is shown in Chemical Formula 1:

[0054] Wherein, A is a core structure with hole transport capability;

[0055] n is a positive integer selected from 2 to 10;

[0056] L a Each occurrence is independently selected from single bond, O, S, N(R1), CH2-N(R1), C(R1)=N, C(O)O, or C(O)N(R1);

[0057] L b Each occurrence is independently selected from single bonds or flexible connecting chains with 1 to 20 carbon atoms;

[0058] L c Each occurrence is independently selected from single bonds, O, S, N(R2), CH2-N(R2), C(R2)=N, C(O)O, or C(O)N(R2);

[0059] Each time L appears a L b and L c Not both are single keys;

[0060] Each time R1 appears, it is independently selected from hydrogen, deuterium, substituted or unsubstituted alkyl groups with 1 to 10 carbon atoms, substituted or unsubstituted cycloalkyl groups with 5 to 10 carbon atoms, substituted or unsubstituted aryl groups with 6 to 18 carbon atoms, and substituted or unsubstituted heteroaryl groups with 5 to 18 carbon atoms.

[0061] Each time R2 appears, it is independently selected from hydrogen, deuterium, substituted or unsubstituted alkyl groups with 1 to 10 carbon atoms, substituted or unsubstituted cycloalkyl groups with 5 to 10 carbon atoms, substituted or unsubstituted aryl groups with 6 to 18 carbon atoms, and substituted or unsubstituted heteroaryl groups with 5 to 18 carbon atoms.

[0062] Ar1 is selected independently each time it appears from aryl groups with 6 to 12 substituted or unsubstituted carbon atoms, or heteroaryl groups with 5 to 12 substituted or unsubstituted carbon atoms.

[0063] In this embodiment, the photosensitive compound includes a parent core structure A and multiple cross-linked side chains. Among them, cross-linked side chains The terminal of the component has an aryl azide group, which can undergo a crosslinking reaction with hole transport materials under light irradiation. The aryl azide group of this crosslinked side chain is connected by a flexible linker. It is connected to the parent nucleus structure A. On the one hand, this The low rigidity breaks or reduces the conjugation between the aryl azide group and the parent structure A to a certain extent. Therefore, the cross-linking reaction of the aryl azide group has little effect on the hole transport capability of the parent structure A. This allows the photosensitive compound to maintain a high hole transport capability after cross-linking, which can effectively compensate for the hole transport capability of the hole transport layer.

[0064] In one embodiment of this disclosure, A is selected from those capable of making Hole mobility greater than 1x10 -4 cm 2 V -1 s -1 The parent nucleus structure, or selected from those capable of making Hole mobility greater than 1x10 -4 cm 2 V -1 s -1 The parent nucleus structure, or selected from those capable of making Hole mobility greater than 1x10 -4 cm 2 V -1 s -1 The parent core structure. In other words, when the cross-linked side chains of the various photosensitive compounds provided in this disclosure... Compounds formed when all are replaced with hydrogen, or compounds formed when all are replaced with methyl, or compounds formed when all are replaced with methoxy, have a concentration greater than 1 x 10⁻⁶. -4 cm 2 V -1 s -1 The hole mobility. Thus, the hole mobility of the photosensitive compound provided in this embodiment is not less than 1 x 102. -4 cm 2 V -1 s -1 .

[0065] In one example of this disclosure, some substituents or hydrogens on a hole transport compound with high hole mobility (which may differ from the hole transport material in the material composition) may be replaced with crosslinked side chains provided in embodiments of this disclosure. This allows these hole transport compounds to be modified into the photosensitive compounds provided in the embodiments of this disclosure. Furthermore, the modified hole transport compound can be referred to as a precursor compound, wherein at least some of the substituents or hydrogen atoms of the precursor compound are replaced by crosslinked side chains to become a photosensitive compound; the hole mobility of the precursor compound corresponding to the photosensitive compound in the material composition is greater than the hole mobility of the hole transport material in the material composition, for example, 2 to 10 times, such as 2, 3, 4, 5, 6, 7, 8, 9, or 10 times.

[0066] In one example, Spiro-MeOTAD or TPD can be used as a precursor compound, which makes the core structure of the photosensitive compound the same as or similar to that of Spiro-MeOTAD or TPD, thereby giving the photosensitive compound the same or similar high hole mobility.

[0067] Of course, in other embodiments of this disclosure, other hole transport materials may also be used as precursor compounds, such as compounds like MeOTTVT or similar compounds.

[0068] In one example, A is selected from those that enable... Hole mobility greater than 5x10 -4 cm 2 V -1 s -1 The parent nucleus structure, or selected from those capable of making Hole mobility greater than 5x10 -4 cm2 V -1 s -1 The parent nucleus structure, or selected from those capable of making Hole mobility greater than 5x10 -4 cm 2 V -1 s -1 The parent nucleus structure.

[0069] In one embodiment of this disclosure, A has the structure shown in Chemical Formula 2:

[0070] Where m is a positive integer selected from 1 to 6, and n≤m*2;

[0071] Ar2 has At least one of the following: aryl group having 6 to 50 substituted or unsubstituted carbon atoms, and electron-rich heteroaryl group having 5 to 50 substituted or unsubstituted carbon atoms;

[0072] Among them, A1, A2, A3, and A4 are each independently selected from substituted or unsubstituted benzene rings, substituted or unsubstituted furan rings, substituted or unsubstituted thiophene rings, substituted or unsubstituted pyrrole rings, fused aromatic rings with 6 to 20 substituted or unsubstituted carbon atoms, and fused heteroaromatic rings with 6 to 20 substituted or unsubstituted carbon atoms.

[0073] Ar3 is selected independently each time it appears from aryl groups with 6 to 18 substituted or unsubstituted carbon atoms, or heteroaryl groups with 6 to 18 substituted or unsubstituted carbon atoms;

[0074] Each time it appears, it is connected to Ar3, and a maximum of two are connected to each Ar3.

[0075] In this embodiment, Ar2 forms a triarylamine structure with each N(Ar3)2, thus the parent structure A has m triarylamine structures (sharing the Ar2 group), which gives the parent structure A a high hole transport capability. In this embodiment, the cross-linked side chains of the photosensitive compound... The Ar3 atom attached to the triarylamine structure allows the crosslinked side chain to be located as far away from the molecular center of the photosensitive compound as possible, reducing the steric hindrance of the parent structure A on the crosslinked side chain and facilitating crosslinking between the crosslinked side chain and the hole transport material. Furthermore, the crosslinked side chain can effectively expand in the solvent, thereby improving the solubility of the photosensitive compound.

[0076] In one example, m is a positive integer from 2 to 6, such as m being 2, 3, 4, 5, or 6.

[0077] In one example, A1, A2, A3, and A4 are each independently selected from unsubstituted benzene rings, naphthylene rings, benzofuran rings, benzothiophene rings, and benzocarbazole rings. For example, A1, A2, A3, and A4 are all selected from benzene rings. Alternatively, one of A1 and A2 may be a benzene ring and the other may be a naphthylene ring, a benzofuran ring, a benzothiophene ring, or a benzocarbazole ring; A3 may be the same as A1, and A4 may be the same as A2. Thus, the parent structure A has a higher hole mobility, which can more effectively compensate for the hole transport capacity of the hole transport layer.

[0078] In one example, Ar3 is independently selected each time it appears from phenyl, naphthyl, diphenyl, terphenyl, fluorenyl, carbazolyl, dibenzofuranyl, and dibenzothiophene.

[0079] In one embodiment of this disclosure, the parent structure A contains at least one of the following groups: substituted or unsubstituted spirofluorenyl, substituted or unsubstituted fluorenyl, substituted or unsubstituted diphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted carbazole, substituted or unsubstituted dibenzothiophene, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted anthraquinone, substituted or unsubstituted phenanthyl, or substituted or unsubstituted pyrene. Further, Ar2 contains at least one of the following groups: substituted or unsubstituted spirofluorenyl, substituted or unsubstituted fluorenyl, substituted or unsubstituted diphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted carbazole, substituted or unsubstituted dibenzothiophene, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted anthraquinone, substituted or unsubstituted phenanthyl, or substituted or unsubstituted pyrene.

[0080] As an example, Ar2 is selected from unsubstituted spirofluorenyl, unsubstituted fluorenyl, unsubstituted diphenyl, unsubstituted terphenyl, unsubstituted carbazolyl, unsubstituted dibenzothiophene, unsubstituted dibenzofuranyl, unsubstituted anthracenel, unsubstituted phenanthrenel, and unsubstituted pyrenel. This ensures that the parent nucleus structure A has a high hole mobility.

[0081] In one example, each Ar3 is selected from a connection.

[0082] In another example, one of the Ar3 atoms in each N(Ar3)2 is selected from the connection of one And the other Ar3 is not connected.

[0083] In one embodiment of this disclosure, the structure of the photosensitive compound is shown as in one of chemical formulas 1-1 and 1-2;

[0084] Each time E appears, it is independently selected from... Hydrogen, deuterium, alkyl groups having 1 to 6 carbon atoms, alkoxy groups having 1 to 6 carbon atoms, alkylamino groups having 2 to 6 carbon atoms, aryl groups having 6 to 12 carbon atoms, and heteroaryl groups having 5 to 12 carbon atoms;

[0085] In chemical formula 1-1, at least two E's are selected from...

[0086] In chemical formulas 1-2, at least four E's are selected from...

[0087] In chemical formula 1-1, G is selected from empty bond, O, S, N (R3), and C (R4R5);

[0088] R3 is selected from substituted or unsubstituted alkyl groups with 1 to 10 carbon atoms, substituted or unsubstituted cycloalkyl groups with 5 to 10 carbon atoms, substituted or unsubstituted aryl groups with 6 to 18 carbon atoms, and substituted or unsubstituted heteroaryl groups with 5 to 18 carbon atoms.

[0089] R4 and R5 are each independently selected from hydrogen, deuterium, substituted or unsubstituted alkyl groups with 1 to 10 carbon atoms, substituted or unsubstituted cycloalkyl groups with 5 to 10 carbon atoms, substituted or unsubstituted aryl groups with 6 to 18 carbon atoms, substituted or unsubstituted heteroaryl groups with 5 to 18 carbon atoms, or R4 and R5 are connected to each other to form a substituted or unsubstituted aliphatic ring or fluorene ring with 5 to 10 carbon atoms.

[0090] In one example, E is not selected. When, it is selected from hydrogen, deuterium, methyl, methoxy, or phenyl.

[0091] In one example, in formula 1-1, the two E's are selected from cross-linked side chains; for example, in each diphenylamine group, one E' is selected from a cross-linked side chain, and the other is not selected from a cross-linked side chain.

[0092] In one example, in chemical formulas 1-2, all eight E's are selected from cross-linked side chains.

[0093] In one example, in chemical formula 1-1, G is selected from N(R3); where R is selected from methyl or phenyl.

[0094] In one example, in chemical formula 1-1, G is selected from C(R4R5); wherein R4 and R5 are both selected from methyl, or both are selected from phenyl, or R4 and R5 are connected to each other to form a fluorene ring with the carbon atom to which they are connected.

[0095] In one embodiment of this disclosure, the structure of the photosensitive compound is shown in chemical formulas 1-3;

[0096] In chemical formulas 1-3, Ar4, Ar5, Ar6, and Ar7 are each independently selected from substituted or unsubstituted phenyl, substituted or unsubstituted naphthyl, or substituted or unsubstituted anthraceneyl. At least two of Ar4, Ar5, Ar6, and Ar7 contain cross-linked side chains. When Ar4, Ar5, Ar6, and Ar7 have substituents, these substituents can be electron-donating substituents (e.g., methyl, methoxy, amino, ethyl, tert-butyl, etc.) or electron-withdrawing substituents (e.g., nitro, acetoxycarbonyl, etc.).

[0097] As an example, at least one of Ar4, Ar5, Ar6, and Ar7 is selected from methoxyphenyl, nitrophenyl, naphthyl, or anthracene.

[0098] In one example, cross-linked side chains The number is 2 to 8. This ensures effective cross-linking between the photosensitive compound and the hole transport material, and allows control over the degree of cross-linking, thereby controlling the hole mobility of the hole transport layer.

[0099] In one embodiment of this disclosure, the photosensitive compound is selected from compounds represented by the following chemical formulas:

[0100] In one embodiment of this disclosure, in at least one In the middle, L a Selected from single bond, L b Selected from single bond, L c Selected from C(R2)=N, C(O)O, or C(O)N(R2). For example, in each cross-linked side chain of the photosensitive compound, L a Selected from single bond, L b Selected from single bond, L c The group is selected from C(R2)=N, C(O)O, or C(O)N(R2). In this embodiment, Lc is an easily synthesized linking group, which reduces the number of steps in the preparation process of the photosensitive compound, thus improving yield and reducing cost. In one example, in each crosslinked side chain, each Lc... c They are the same, for example, both are ester groups.

[0101] In one embodiment of this disclosure, L a Each occurrence is independently selected from single bonds, CH2-N(R1), C(R1)=N, or C(O)O, for example, independently selected from hydrogen, CH2-NH, CH=N, or C(O)-O. This is beneficial for the synthesis of photosensitive compounds.

[0102] In one embodiment of this disclosure, L bEach time it appears, it is independently selected from single-bonded or straight-chain alkanes with 2 to 18 carbon atoms. Especially when L b When selected from straight-chain alkanes having 2 to 18 carbon atoms, the cross-linked side chains of the photosensitive compound can have greater flexibility; simultaneously, this L b The flexible carbon chain gives the photosensitive compound a high solubility, while the carbon chain is not too long to avoid reducing the film retention rate during film formation.

[0103] In one embodiment of this disclosure, L c Each occurrence is independently selected from single bonds, CH2-N(R2), C(R2)=N, or C(O)O; for example, independently selected from hydrogen, CH2-NH, CH=N, or C(O)-O. This is beneficial for the synthesis of photosensitive compounds.

[0104] In another embodiment of this disclosure, in at least one In the middle, L a Selected from O, S, N(R1), CH2-N(R1), C(R1)=N, C(O)O, or C(O)N(R1); L b Selected from straight-chain alkanes with 2–18 carbon atoms, substituted branched alkanes with 2–18 carbon atoms in the main chain, oxa-straight-chain alkanes with 2–18 carbon atoms, substituted or unsubstituted alkenyl groups with 2–18 carbon atoms in the main chain, and substituted or unsubstituted alkynyl groups with 2–18 carbon atoms in the main chain; L c Selected from O, S, N(R2), CH2-N(R2), C(R2)=N, C(O)O or C(O)N(R2).

[0105] For example, in each cross-linked side chain, L a Selected from O, S, N(R1), CH2-N(R1), C(R1)=N, C(O)O, or C(O)N(R1); L b Selected from straight-chain alkanes with 2–18 carbon atoms, substituted branched alkanes with 2–18 carbon atoms in the main chain, oxa-straight-chain alkanes with 2–18 carbon atoms, substituted or unsubstituted alkenyl groups with 2–18 carbon atoms in the main chain, and substituted or unsubstituted alkynyl groups with 2–18 carbon atoms in the main chain; L c Selected from O, S, N(R2), CH2-N(R2), C(R2)=N, C(O)O or C(O)N(R2).

[0106] In one example, in each crosslinked side chain, each L a They are the same, for example, both are ester groups, or both are CH2-NH.

[0107] In one example, in each crosslinked side chain, each L bThey are the same, for example, all are straight-chain alkanes with 2 to 18 carbon atoms, especially straight-chain alkanes with 4 to 8 carbon atoms. For example, each L... b All are n-butyl, pentyl, hexyl, heptyl, or octyl.

[0108] In one example, in each crosslinked side chain, each L c They are the same, for example, both are ester groups or CH=N.

[0109] In one embodiment of this disclosure, each time Ar1 appears, it is independently selected from aryl groups with 6 to 12 substituted carbon atoms and heteroaryl groups with 5 to 12 substituted carbon atoms; wherein, each time the substituent on Ar1 appears, it is independently selected from deuterium, halogen, and alkyl groups with 1 to 4 carbon atoms; each time Ar1 appears, the number of substituents on Ar1 is one or more, and any two substituents are the same or different.

[0110] In one example, Ar1 is fully substituted each time it appears; at least one substituent on Ar1 is fluorine, and the remaining substituents are selected from deuterium, bromine, iodine, and alkyl groups having 1 to 4 carbon atoms (e.g., methyl, ethyl, isopropyl, tert-butyl).

[0111] In one example, Ar1 is independently selected from tetrasubstituted phenyl groups each time it appears.

[0112] In one example, the Ar1 of each crosslinked side chain is the same.

[0113] In one example, It has the structure shown in chemical formula 3:

[0114] Each R6 is independently selected from deuterium, halogens, or alkyl groups having 1 to 4 carbon atoms; any two R6s may be the same or different.

[0115] In the same group represented by chemical formula 3, 1 to 4 R6s are selected from fluorine.

[0116] As an example, each R6 is fluorine, or two of the R6s are fluorine.

[0117] In one example, in the same group represented by Formula 3, R6 is selected from fluorine or tert-butyl, for example, at least one R6 is selected from tert-butyl. Tert-butyl has strong electron-donating properties and a large volume, which not only makes the photosensitive compound more likely to undergo cross-linking reactions under light, but also helps to improve the solubility of the photosensitive compound. When the material composition needs to be prepared using photolithography to fabricate a patterned hole transport layer, tert-butyl can facilitate development.

[0118] In one example, within the same group represented by Formula 3, two R6 groups are selected from fluorine, and the other two R6 groups are selected from electron-donating substituents, such as methyl, ethyl, tert-butyl, isopropyl, etc. On the one hand, having two alkyl substituents allows for a balance between improving crosslinking efficiency and improving development efficiency. If the number of alkyl substituents is further increased, the steric hindrance around the azide of the photosensitive compound further increases, which is detrimental to the crosslinking reaction. If the number of alkyl groups is further reduced, the solubility of the photosensitive compound decreases, which is detrimental to the elution of uncrosslinked material compositions during development.

[0119] In one embodiment of this disclosure, the photosensitive compound is selected from the group consisting of:

[0120] In one embodiment of this disclosure, the hole transport material in the material composition is selected from at least one of the following materials: a hole transport compound containing a fluorene ring, a hole transport polymer containing a fluorene ring, a hole transport compound containing a carbazole ring, a hole transport polymer containing a carbazole ring, a hole transport compound containing a dibenzofuran ring, a hole transport polymer containing a dibenzofuran ring, a hole transport compound containing a dibenzothiophene ring, and a hole transport polymer containing a dibenzothiophene ring.

[0121] For example, the hole transport material in the material composition is selected from TFB or PBCZCZ.

[0122] This disclosure also provides a light-emitting element, as shown in FIG1. ​​The light-emitting element is a thin-film light-emitting element, which may include an anode 100, a hole transport layer 300, a light-emitting layer and a cathode 600 stacked in sequence.

[0123] In one example, the hole transport layer 300 of the light-emitting element is prepared using the first material composition provided in this disclosure, thus having a high hole migration capability, which can ensure that the light-emitting element has a high luminous efficiency.

[0124] In another example, the light-emitting layer of the light-emitting element is a quantum dot layer prepared using the second material composition provided in this disclosure, which has a high hole migration capability and can ensure that the light-emitting element has a high luminous efficiency.

[0125] In another example, the hole transport layer 300 of the light-emitting element is prepared using the first material composition provided in this disclosure, and the light-emitting layer of the light-emitting element is a quantum dot layer prepared using the second material composition provided in this disclosure. The photosensitive compound in the first material composition may be the same as or different from the photosensitive compound in the second material composition.

[0126] In other examples disclosed herein, the light-emitting layer may also employ other light-emitting materials besides quantum dots, such as organic light-emitting small molecule materials, organic light-emitting polymers, etc. For example, the light-emitting element may be an OLED or a PLED.

[0127] In one example, the light-emitting element may further include a hole injection layer 200 located between the anode 100 and the hole transport layer 300.

[0128] In one example, the light-emitting element may also include an electron transport layer 500 located between the cathode 600 and the light-emitting layer.

[0129] This disclosure may also provide a light-emitting panel having the light-emitting element, the light-emitting panel having an array of light-emitting elements. The light-emitting panel may be a display panel for display, a lighting panel for illumination, a vehicle light panel for marking status, or applied to other scenarios requiring light.

[0130] In one example, the hole transport layer on the light-emitting panel is a single layer, and each light-emitting element can share the same hole transport layer.

[0131] In another example, the hole transport layer on the light-emitting panel is patterned, with gaps between at least some of the hole transport layers of adjacent light-emitting elements. For example, multiple non-connected hole transport layers can be formed on a substrate using the material composition provided in this disclosure and a photolithography process, such as forming hole transport layers corresponding one-to-one with each light-emitting element. Embodiments of this disclosure also provide a display device comprising any of the light-emitting panels described in the above-described light-emitting panel embodiments. This display device can be a smartphone screen, a smartwatch screen, a television screen, a vehicle display screen, or other types of display devices. Since this display device has any of the light-emitting panels described in the above-described light-emitting panel embodiments, it has the same beneficial effects, which will not be repeated here.

[0132] The preparation and performance of the photosensitive compounds provided in this disclosure are illustrated below with reference to several specific embodiments.

[0133] Example 1

[0134] Preparation of Spiro-MeOTAD carbon chain-linked photosensitive compound (compound 1)

[0135] Under nitrogen protection, 3 g of compound 1a (N2, N2, N2', N2', N7, N7, N7', N7'-octa(4-methoxyphenyl)-9,9'-spiro[fluorene]-2,2',7,7'-tetraamine) was dissolved in dichloromethane (DCM) in a 500 mL three-necked flask. The solution was cooled to -30°C using acetone and dry ice, and 16 mL of boron tribromide dichloromethane solution (1 mol / L) was added dropwise. The mixture was allowed to warm to room temperature and stirred overnight. Post-treatment: 10% potassium hydroxide solution was added dropwise to adjust the pH to 13, and the aqueous phase was extracted with dichloromethane. Then, 10% hydrochloric acid aqueous solution was added dropwise to adjust the pH to 3, accompanied by the precipitation of a large amount of solid. The solution was centrifuged and dried to obtain 1.85 g of compound 1b. The product's 1H NMR spectrum is as follows: 9.45 (s, 8H), 8.32-7.83 (m, 12H), 7.79-7.43 (m, 32H). The product's mass spectrum is MS[M+1] = 1113.38.

[0136] 500 mg of compound 1b was dissolved in 5 mL of DMF (N,N-dimethylformamide) in a 50 mL single-necked flask. 1.1 g of 6-((tert-butyldimethylsilyl)oxy)hexanoyl chloride and 1.2 g of triethylamine were added, and the mixture was reacted overnight at room temperature. Post-treatment: The reaction solution was added to 100 mL of dichloromethane, washed three times with 50 mL of saturated sodium chloride solution, dried over anhydrous sodium sulfate, and evaporated to dryness for further use.

[0137] Add 20 mL of tetrahydrofuran to the crude product from the previous step, and react with 4 mL of TBAF (tetrabutylammonium fluoride) in a tetrahydrofuran solution (1 mol / L) overnight at room temperature. Post-treatment: Add 3 g of silica gel to the reaction solution and perform column chromatography. 454 mg of compound 1c was obtained. The 1H NMR spectrum of the product is as follows: 8.81–7.41 (m, 8H), 8.22–7.84 (m, 36H), 4.73 (s, 8H), 3.63–3.42 (m, 16H), 2.57–2.49 (m, 16H), 1.66–1.48 (m, 32H), 1.24–1.22 (m, 16H). The mass spectra of the product are MS[M+1] = 2027.40.

[0138] 450 mg of compound 1c was dissolved in 5 mL of DMF in a 50 mL single-necked flask, and 1.17 g of 4-azido-2,3,5,6-benzoyl chloride and 1.31 g of triethylamine (TEA) were added. The reaction was carried out overnight at room temperature. Post-treatment: The reaction solution was added to 100 mL of dichloromethane, washed three times with 50 mL of saturated sodium chloride water, dried over anhydrous sodium sulfate, evaporated to dryness, and subjected to column chromatography to obtain compound 1. The 1H NMR spectrum of the product is as follows: 8.81–8.43 (m, 12H), 8.34–8.02 (m, 32H), 3.57–3.39 (m, 16H), 2.54–2.49 (m, 16H), 1.67–1.43 (m, 32H), 1.22–1.13 (m, 16H). The mass spectra of the product are MS[M+1] = 3762.98.

[0139] In the film formation process, the material composition containing Spiro-MeOTAD carbon chain-linked photosensitive compound (compound 1) and TFB (as hole transport material) allows compound 1 to crosslink with TFB, achieving a film retention rate of over 95%. This embodiment also included performance comparison tests, fabricating a control QLED device and a test QLED. The only difference between the control and test QLEDs was that the control QLED's hole transport layer did not contain compound 1 (the hole transport material was TFB) during fabrication, while the test QLED's hole transport layer contained compound 1. Test results showed that the test QLED exhibited improved current efficiency, indicating that compound 1 can compensate for the decreased hole transport capability of the hole transport layer, resulting in a better hole transport capability.

[0140] Example 2

[0141] Preparation of Spiro-MeOTAD ester-linked photosensitive compound (compound 2)

[0142] See Example 1 for preparation of compound 1b.

[0143] 600 mg of compound 1b was dissolved in 6 mL of DMF in a 50 mL single-necked flask, and 1.03 g of 4-azido-2,3,5,6-benzoyl chloride and 1.18 g of triethylamine were added. The reaction was carried out overnight at room temperature. Post-treatment: The reaction solution was added to 100 mL of dichloromethane, washed three times with 50 mL of saturated sodium chloride water, dried over anhydrous sodium sulfate, evaporated to dryness, and subjected to column chromatography, or compound 2. The 1H NMR spectrum of the product is as follows: 7.89–7.71 (m, 12H), 7.68–6.92 (m, 32H). The mass spectra of the product are MS[M+1] = 2850.43.

[0144] In the film formation process, the material composition containing Spiro-MeOTAD ester-linked photosensitive compound (compound 2) and TFB (as a hole transport material) allows compound 2 to crosslink with TFB, achieving a film retention rate of over 95%. This embodiment also included performance comparison tests, fabricating a control QLED device and a test QLED. The only difference between the control and test QLEDs was that the control QLED's hole transport layer did not contain compound 2 (the hole transport material was TFB) during fabrication, while the test QLED's hole transport layer contained compound 2. Test results showed that the test QLED exhibited improved current efficiency, indicating that compound 2 can compensate for the decreased hole transport capability of the hole transport layer, resulting in a better hole transport capability.

[0145] Example 3

[0146] Preparation of compound 3

[0147] Under nitrogen protection, 0.75 g of compound 3a (4-(diphenylamino)benzaldehyde) and 20 mL of dichloromethane were added to a 100 mL three-necked flask. The mixture was cooled to 0°C, and the system remained colorless. 3.4 mL of methanesulfonic acid (MsOH) was added; during the addition of methanesulfonic acid, the system turned red, and the temperature rise was not significant. The mixture was kept at 0°C for 5 minutes, and then 1.35 g of 4-chlorobenzoquinone was added; the system remained red. The mixture was allowed to return to room temperature and stirred overnight at 40°C. Post-processing: TLC monitoring was performed, but some starting material remained. The system was cooled to 0°C, and 15 mL of saturated sodium bicarbonate solution was added. The mixture was separated and dried. Column chromatography was performed to obtain 457 mg of compound 3b. The product's 1H NMR spectrum is as follows: 9.92 (s, 2H), 7.55–7.48 (m, 6H), 7.38–7.31 (m, 8H), 7.38–7.31 (m, 8H), 7.28–7.26 (m, 4H). The product's mass spectrum is ms[M+1] = 545.20.

[0148] Under nitrogen protection, 46.9 mg of compound 3b and 5 mL of ethanol were added to a 50 mL single-necked flask, followed by 47 mg of an amine compound (Boc-protected ethylenediamine) and one drop of acetic acid (catalytic reaction). The temperature was raised to 50°C, and the system turned yellow. Initially, compound 3b showed poor solubility in ethanol, but gradually dissolved as the reaction proceeded. The reaction was maintained at this temperature overnight. Post-treatment: TLC monitoring (using sodium borohydride to quench the reaction) showed no residue, yielding compound 3c. No further treatment was needed; the next reaction was carried out directly.

[0149] Next, 47.8 mg of sodium borohydride was added to the reactor, and the reaction was carried out for 3 hours. The reaction was monitored by TLC until the reactants were fully reacted. Post-treatment: 30 mL of dichloromethane was added to a 100 mL separatory funnel, the reaction mixture was transferred, washed once with 10 mL of water, dried, and evaporated to dryness. 127 mg of compound 3d (crude product) was obtained.

[0150] Under nitrogen protection, compound 3d (crude product) and 5 mL of dichloromethane were added to a 50 mL single-necked flask, followed by the addition of 160 μL of trifluoroacetic acid. The system turned yellow. The reaction was carried out at room temperature for 4 hours. Post-treatment: TLC monitoring showed no remaining material. 30 mL of dichloromethane was added to a 100 mL separatory funnel, the reaction mixture was transferred, and washed with 10 mL of saturated sodium bicarbonate solution and 10 mL of saturated sodium chloride solution. The mixture was dried, evaporated to dryness, and subjected to column chromatography to obtain 77.8 mg of compound 3e (crude product). The 1H NMR spectrum of the product is as follows: 7.57-7.47 (m, 4H), 7.38-7.33 (m, 6H), 7.32-7.30 (m, 8H), 7.28-7.26 (m, 4H), 7.09-7.00 (m, 6H), 4.18 (s, 2H), 3.66-3.61 (m, 4H), 2.63-2.53 (m, 6H), 1.59-1.45 (m, 16H), 1.24 (m, 4H). The mass spectrum of the product is: MS[M+1] = 745.72.

[0151] Under nitrogen protection, 77.8 mg of compound 3e (crude product) and 5 mL of ethanol were added to a 50 mL single-necked flask, followed by 114 mg of 4-azido-2,3,5,6-benzaldehyde and one drop of acetic acid. The reaction was carried out overnight at room temperature. Post-treatment: TLC monitoring showed no remaining material. The product was evaporated to dryness and subjected to column chromatography. 87.6 mg of compound 3 was obtained. The 1H NMR spectra of the product are as follows: 8.32 (s, 2H), 7.59–7.49 (m, 4H), 7.40–7.35 (m, 8H), 7.28–7.26 (m, 8H), 7.09–7.00 (m, 6H), 4.18 (s, 2H), 3.66–3.61 (m, 4H), 2.63–2.53 (m, 6H), 1.59–1.45 (m, 16H). Product mass spectrometry information: MS[M+1] = 1147.52.

[0152] When the material composition of compound 3 and TFB (as a hole transport material) is used for film formation, compound 3 can crosslink with TFB, achieving a film retention rate of over 95%. This embodiment also included performance comparison tests, preparing a control QLED device and a test QLED. The only difference between the control and test QLEDs was that the control QLED's hole transport layer did not contain compound 3 (the hole transport material was TFB) during preparation, while the test QLED's hole transport layer contained compound 3. Test results showed that the test QLED exhibited improved current efficiency, indicating that compound 3 can compensate for the decrease in hole transport capability of the hole transport layer, resulting in a better hole transport capability.

[0153] Example 4

[0154] Preparation of compound 4

[0155] Under nitrogen protection, 4 g of compound 4a (4-methoxy-N,N-diphenylaniline) and 20 mL of dichloromethane were added to a 100 mL three-necked flask. The mixture was cooled to 0°C, and the system remained colorless. 16 mL of methanesulfonic acid was then added; the system turned red during the addition of methanesulfonic acid, with no significant temperature increase. The mixture was kept at 0°C for 5 minutes, and then 7.8 g of 4-chlorobenzoquinone was added; the system turned blue. The mixture was then allowed to return to room temperature and stirred overnight. Post-processing: TLC monitoring was performed, but some reactants remained. The system was cooled to 0°C, and 50 mL of saturated sodium bicarbonate solution was added. The mixture was separated and dried. Column chromatography was performed to obtain 2.2 g of compound 4b. The 1H NMR spectrum is: 7.55-7.48 (m, 4H), 7.38-7.31 (m, 8H), 7.38-7.31 (m, 8H), 7.09-7.00 (m, 6H), 3.65 (s, 6H).

[0156] Under nitrogen protection, 1 gram of compound 4b and 20 mL of dichloromethane were added to a 100 mL three-necked flask. The mixture was cooled to -30°C, and the system turned blue. 10 mL of boron tribromide was then added dropwise. During the addition of boron tribromide, the system turned red, and the temperature increase was not significant. The mixture was allowed to return to room temperature and stirred overnight. 50 mL of 10% potassium hydroxide solution was added to the reaction mixture to adjust the pH to 14. 100 mL of dichloromethane was then added, and the aqueous phase was extracted. 10% hydrochloric acid was added to the aqueous phase to adjust the pH to 1. The mixture was then extracted twice with 200 mL of dichloromethane and dried to obtain 380 mg of compound 4c.

[0157] 350 mg of compound 4c was dissolved in 6 mL of DMF in a 50 mL single-necked flask, and 920 mg of 4-azido-2,3,5,6-benzoyl chloride and 1.02 g of triethylamine were added. The reaction was carried out overnight at room temperature. Post-treatment: The reaction solution was added to 100 mL of dichloromethane, washed three times with 50 mL of saturated sodium chloride water, dried over anhydrous sodium sulfate, evaporated to dryness, and subjected to column chromatography to obtain compound 4. The 1H NMR spectrum of the product is as follows: 7.55–7.50 (m, 4H), 7.38–7.32 (m, 8H), 7.38–7.29 (m, 8H), 7.28–7.21 (m, 6H). The mass spectra of the product are MS[M+1] = 955.43.

[0158] When the material composition of compound 4 and TFB (as a hole transport material) is used for film formation, compound 4 can crosslink with TFB, achieving a film retention rate of over 95%. This embodiment also included performance comparison tests, preparing a control QLED device and a test QLED. The only difference between the control and test QLEDs was that the control QLED's hole transport layer did not contain compound 4 (the hole transport material was TFB) during preparation, while the test QLED's hole transport layer contained compound 4. Test results showed that the test QLED exhibited improved current efficiency, indicating that compound 4 can compensate for the decrease in hole transport capability of the hole transport layer, resulting in a better hole transport capability.

[0159] After obtaining compounds 1 to 4, QLEDs can be prepared and tested separately. Specifically, control QLEDs, test QLED11, test QLED12, test QLED21, test QLED22, test QLED31, test QLED41, and test QLED42 were prepared.

[0160] The method for preparing any QLED is as follows:

[0161] 1) Perform ultraviolet and ozone treatment on the ITO substrate (ITO layer + glass layer).

[0162] 2) A hole injection layer is formed on the ITO substrate. The hole injection layer is made of PF8CZ and has a thickness of 24nm.

[0163] 3) A hole transport precursor solution containing TFB was spin-coated, and the solution was then irradiated to form a hole transport layer. The TFB content in the hole transport precursor solution was 10% by mass. The thickness of the formed hole transport layer was 20 nm.

[0164] 4) A quantum dot layer is formed on the hole transport layer. The thickness of the quantum dot layer is 25 nm, the emission color is red, and the quantum dot material is CdSe / Zns.

[0165] 5) An electron transport layer was fabricated on the quantum dot layer. The electron transport layer was made of ZnMgO and had a thickness of 28 nm.

[0166] A cathode was fabricated on the electron transport layer. The cathode was made of aluminum and had a thickness of 120 nm.

[0167] The differences between the control QLED, test QLED11, test QLED12, test QLED21, test QLED22, test QLED31, test QLED41, and test QLED42 lie only in the hole transport precursor solution (the photosensitive compound and its concentration in the precursor solution are different); all other parameters are the same. In each embodiment, the feed ratio of each material and the film formation process are fixed during the preparation of the electron transport layer, meaning that the electron transport layers prepared in each embodiment are identical. In ZnMgO, the Mg doping content does not exceed 50%. The hole transport precursor solution used to form the control QLED does not contain any photosensitive compound.

[0168] The hole transport precursor solution used to form the test QLED11 contains 0.05% by mass of compound 1;

[0169] The hole transport precursor solution used to form the test QLED12 contains 0.08% by mass of compound 1;

[0170] The hole transport precursor solution used to form the test QLED21 contains 0.05% by mass of compound 2.

[0171] The hole transport precursor solution used to form the test QLED22 contains 0.08% by mass of compound 2;

[0172] The hole transport precursor solution used to form the test QLED31 contains 0.05% by mass of compound 3;

[0173] The hole transport precursor solution used to form the test QLED41 contains 0.05% by mass of compound 4.

[0174] The hole transport precursor solution used to form test QLED42 contained 0.08% by mass of compound 4. Performance tests were performed on the control QLED, test QLED11, test QLED12, test QLED21, test QLED22, test QLED31, test QLED41, and test QLED42. The test results are shown in Figures 2 and 3.

[0175] Referring to Figures 2 and 3, it can be seen that when the four photosensitive compounds, such as Compound 1 to Compound 4, provided in the embodiments of this disclosure are used to prepare the hole transport layer of QLED, they have a relatively small impact on the turn-on voltage of QLED, but can effectively increase the current density of QLED, which is beneficial to improving the luminous efficiency of QLED.

[0176] Other embodiments of this disclosure will readily occur to those skilled in the art upon consideration of the specification and practice of the invention disclosed herein. This application is intended to cover any variations, uses, or adaptations of this disclosure that follow the general principles of this disclosure and include common knowledge or customary techniques in the art not disclosed herein. The specification and examples are to be considered exemplary only, and the true scope and spirit of this disclosure are indicated by the appended claims.

Claims

1. A photosensitive compound, wherein, The structural formula of the photosensitive compound is shown in Chemical Formula 1: Wherein, A is a core structure with hole transport capability; n is a positive integer selected from 2 to 10; L a Each occurrence is independently selected from single bond, O, S, N(R1), CH2-N(R1), C(R1)=N, C(O)O, or C(O)N(R1); L b Each occurrence is independently selected from single bonds or flexible connecting chains with 1 to 20 carbon atoms; L c Each occurrence is independently selected from single bonds, O, S, N(R2), CH2-N(R2), C(R2)=N, C(O)O, or C(O)N(R2); Each time L appears a L b and L c Not both are single keys; Each time R1 appears, it is independently selected from hydrogen, deuterium, substituted or unsubstituted alkyl groups with 1 to 10 carbon atoms, substituted or unsubstituted cycloalkyl groups with 5 to 10 carbon atoms, substituted or unsubstituted aryl groups with 6 to 18 carbon atoms, and substituted or unsubstituted heteroaryl groups with 5 to 18 carbon atoms. Each time R2 appears, it is independently selected from hydrogen, deuterium, substituted or unsubstituted alkyl groups with 1 to 10 carbon atoms, substituted or unsubstituted cycloalkyl groups with 5 to 10 carbon atoms, substituted or unsubstituted aryl groups with 6 to 18 carbon atoms, and substituted or unsubstituted heteroaryl groups with 5 to 18 carbon atoms. Ar1 is selected independently each time it appears from aryl groups with 6 to 12 substituted or unsubstituted carbon atoms, or heteroaryl groups with 5 to 12 substituted or unsubstituted carbon atoms.

2. The photosensitive compound according to claim 1, wherein, A is selected from those that enable... Hole mobility greater than 1x10 -4 cm 2 V -1 s -1 The parent nucleus structure, or selected from those capable of making Hole mobility greater than 1x10 -4 cm 2 V -1 s -1 The parent nucleus structure, or selected from those capable of making Hole mobility greater than 1x10 -4 cm 2 V -1 s -1 The parent nucleus structure.

3. The photosensitive compound according to claim 1, wherein, The A has the structure shown in Chemical Formula 2: Where m is a positive integer selected from 1 to 6, and n≤m*2; Ar2 has At least one of the following: aryl group having 6 to 50 substituted or unsubstituted carbon atoms, and electron-rich heteroaryl group having 5 to 50 substituted or unsubstituted carbon atoms; Among them, A1, A2, A3, and A4 are each independently selected from substituted or unsubstituted benzene rings, substituted or unsubstituted furan rings, substituted or unsubstituted thiophene rings, substituted or unsubstituted pyrrole rings, fused aromatic rings with 6 to 20 substituted or unsubstituted carbon atoms, and fused heteroaromatic rings with 6 to 20 substituted or unsubstituted carbon atoms. Ar3 is selected independently each time it appears from aryl groups with 6 to 18 substituted or unsubstituted carbon atoms, or heteroaryl groups with 6 to 18 substituted or unsubstituted carbon atoms; Each time it appears, it is connected to Ar3, and a maximum of two are connected to each Ar3.

4. The photosensitive compound according to claim 3, wherein, The A group contains at least one of the following groups: substituted or unsubstituted spirofluorenyl, substituted or unsubstituted fluorenyl, substituted or unsubstituted diphenyl, substituted or unsubstituted terphenyl, substituted or unsubstituted carbazolyl, substituted or unsubstituted dibenzothiophene, substituted or unsubstituted dibenzofuranyl, substituted or unsubstituted anthracene, substituted or unsubstituted phenanthryl, or substituted or unsubstituted pyrene.

5. The photosensitive compound according to claim 1, wherein, The structure of the photosensitive compound is shown in one of chemical formulas 1-1 and 1-2; Each time E appears, it is independently selected from... Hydrogen, deuterium, alkyl groups having 1 to 6 carbon atoms, alkoxy groups having 1 to 6 carbon atoms, alkylamino groups having 2 to 6 carbon atoms, aryl groups having 6 to 12 carbon atoms, and heteroaryl groups having 5 to 12 carbon atoms; In chemical formula 1-1, at least two E's are selected from... In chemical formulas 1-2, at least four E's are selected from... In chemical formula 1-1, G is selected from empty bond, O, S, N (R3), and C (R4R5); R3 is selected from substituted or unsubstituted alkyl groups with 1 to 10 carbon atoms, substituted or unsubstituted cycloalkyl groups with 5 to 10 carbon atoms, substituted or unsubstituted aryl groups with 6 to 18 carbon atoms, and substituted or unsubstituted heteroaryl groups with 5 to 18 carbon atoms. R4 and R5 are each independently selected from hydrogen, deuterium, substituted or unsubstituted alkyl groups with 1 to 10 carbon atoms, substituted or unsubstituted cycloalkyl groups with 5 to 10 carbon atoms, substituted or unsubstituted aryl groups with 6 to 18 carbon atoms, substituted or unsubstituted heteroaryl groups with 5 to 18 carbon atoms, or R4 and R5 are connected to each other to form a substituted or unsubstituted aliphatic ring or fluorene ring with 5 to 10 carbon atoms.

6. The photosensitive compound according to claim 1, wherein, The photosensitive compound is selected from compounds with the following chemical formulas:

7. The photosensitive compound according to any one of claims 1 to 6, wherein, In at least In the middle, L a Selected from single bond, L b Selected from single bond, L c Selected from C(R2)=N, C(O)O, or C(O)N(R2).

8. The photosensitive compound according to any one of claims 1 to 6, wherein, In at least middle, L a Selected from O, S, N(R1), CH2-N(R1), C(R1)=N, C(O)O, or C(O)N(R1); L b Selected from straight-chain alkanes with 2 to 18 carbon atoms, substituted branched alkanes with 2 to 18 carbon atoms in the main chain, oxa-straight-chain alkanes with 2 to 18 carbon atoms, substituted or unsubstituted alkenyl groups with 2 to 18 carbon atoms in the main chain, and substituted or unsubstituted alkynyl groups with 2 to 18 carbon atoms in the main chain. L c Selected from O, S, N(R2), CH2-N(R2), C(R2)=N, C(O)O or C(O)N(R2).

9. The photosensitive compound according to any one of claims 1 to 6, wherein, L a Each occurrence is independently selected from single bonds, CH2-N(R1), C(R1)=N, or C(O)O; L b Each time it appears, it is independently selected from single-bonded or straight-chain alkanes with 2 to 18 carbon atoms; L c Each occurrence is independently selected from single bonds, CH2-N(R2), C(R2)=N, or C(O)O.

10. The photosensitive compound according to any one of claims 1 to 6, wherein, Each time Ar1 appears, it is independently selected from aryl groups with 6 to 12 substituted carbon atoms and heteroaryl groups with 5 to 12 substituted carbon atoms; wherein, each time the substituent on Ar1 appears, it is independently selected from deuterium, halogen, and alkyl groups with 1 to 4 carbon atoms; Each time Ar1 appears, the number of substituents on Ar1 is one or more, and any two substituents are the same or different.

11. The photosensitive compound according to claim 10, wherein, Ar1 is fully substituted each time it appears; at least one substituent on Ar1 is fluorine, and the remaining substituents are selected from deuterium, bromine, iodine, and alkyl groups having 1 to 4 carbon atoms.

12. The photosensitive compound according to any one of claims 1 to 6, wherein, It has the structure shown in chemical formula 3: Each R6 is independently selected from deuterium, halogens, or alkyl groups having 1 to 4 carbon atoms; any two R6s may be the same or different. In the same group represented by chemical formula 3, 1 to 4 R6s are selected from fluorine.

13. The photosensitive compound according to claim 1, wherein, The photosensitive compound is selected from the group consisting of the following compounds:

14. A material composition, wherein, The material composition comprises a hole transport material and a photosensitive compound according to any one of claims 1 to 13; the photosensitive compound is capable of crosslinking with the hole transport material under light irradiation.

15. The material composition according to claim 14, wherein, The hole transport material is selected from at least one of the following materials: hole transport compounds containing a fluorene ring, hole transport polymers containing a fluorene ring, hole transport compounds containing a carbazole ring, hole transport polymers containing a carbazole ring, hole transport compounds containing a dibenzofuran ring, hole transport polymers containing a dibenzofuran ring, hole transport compounds containing a dibenzothiophene ring, and hole transport polymers containing a dibenzothiophene ring.

16. A hole transport layer, wherein, The hole transport layer is prepared using the material composition described in claim 14 or 15.

17. A material composition, wherein, The material composition comprises ligand-modified quantum dot materials and the photosensitive compound according to any one of claims 1 to 13; the photosensitive compound is capable of crosslinking with the ligand under light irradiation.

18. A quantum dot layer, wherein, The quantum dot layer is prepared using the material composition of claim 17.

19. A light-emitting element, comprising an anode, a hole transport layer, a light-emitting layer, and a cathode stacked sequentially; in, The hole transport layer of the light-emitting element is the hole transport layer of claim 16; and / or, the light-emitting layer of the light-emitting element is the quantum dot layer of claim 18.

20. A light-emitting panel comprising an array of light-emitting elements as described in claim 19; wherein, There is a gap between the hole transport layers of at least two adjacent light-emitting elements.

21. A display device comprising the light-emitting panel of claim 20.

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