Hole transport materials, light-emitting devices, display panels and display equipment

Abstract

This application discloses a hole transport material, a light-emitting device, a display panel, and a display apparatus. The hole transport material comprises a compound as shown in formula (1) or a polymer with a structure as shown in formula (1): Ar1, Ar2, and Ar3 are selected from any one of carbazole and its derivatives, fluorene and its derivatives, and triphenylamine and its derivatives; the values ​​of i, m, and n range from 0 to 1, and i+m+n=1; at least one of Ar1, Ar2, and Ar3 contains a substituent R1, and R1 contains at least one hydroxyl group. By introducing hydroxyl groups onto the hole transport material, the interaction force between the hole transport material and the light-emitting material is reduced, the residue of the light-emitting material during development is reduced, the color mixing problem can be improved, and the color accuracy can be increased.

Description

Technical Field

[0001] This application relates to the field of display technology, and in particular to a hole transport material, a light-emitting device, a display panel, and a display equipment. Background Technology

[0002] As a crucial component of information technology and the terminal human-machine interface of the information chain, displays are applied across various aspects of daily life, including industry, transportation, communications, education, aerospace, satellite remote sensing, entertainment, and healthcare, making them a vital pillar of the information industry. Among these, light-emitting diode (LED) display technology boasts advantages such as high color gamut, long potential lifespan, excellent viewing angle, and low cost, making it a highly promising future display technology.

[0003] When using photolithography to fabricate the emitting layer of a light-emitting diode (LED), the emitting material needs to be stripped from the non-display areas after film formation. However, existing hole transport materials and emitting materials have strong van der Waals forces, causing emitting material to remain on the hole transport material, resulting in development residue and leading to color mixing and inaccurate color rendering.

[0004] The above statements are for the purpose of providing background information in relation to this application only and do not necessarily constitute prior art. Summary of the Invention

[0005] The main technical problem addressed by this application is to provide a hole transport material, a light-emitting device, and a display panel that can reduce development residue, improve color mixing, and enhance color accuracy.

[0006] To solve the above-mentioned technical problems, one technical solution adopted in this application is: a hole transport material, comprising a compound as shown in formula (1) or a polymer with a structure as shown in formula (1):

[0007]

[0008] Ar1, Ar2, and Ar3 are selected from any one of carbazole and its derivatives, fluorene and its derivatives, and triphenylamine and its derivatives, respectively; the values ​​of i, m, and n are in the range of 0-1, and i+m+n=1; at least one of Ar1, Ar2, and Ar3 has a substituent R1, and R1 contains at least one alkyl group.

[0009] By introducing hydroxyl groups on the periphery of the hole transport material, the interaction force between the hole transport material and the quantum dots is reduced, thus reducing the residue of quantum dots during development, improving color mixing problems, and enhancing color accuracy.

[0010] In one embodiment, the number-average molecular weight of the polymer is 10,000-100,000. Hole transport materials with the above-mentioned number-average molecular weight form more uniform films and have better film repeatability.

[0011] In one embodiment, the values ​​of i, m, and n range from 0.05 to 0.95. This configuration improves the carrier transport and injection performance of the hole transport material.

[0012] In one embodiment, the hydrocarbon oxygen group includes one or more of alkoxy, aryloxy, and olefinoxy groups. This expands the range of optional hole transport materials.

[0013] In one embodiment, the chemical formula of R1 is -R2-(OR3). a , where 'a' is an integer greater than or equal to 1, -(OR3) a The alkoxy group is an alkoxy group, and one or more of the alkoxy groups are connected to R2 as terminal groups or branched groups. The alkoxy group can reduce the interaction force between the quantum dot and the inner alkyl group of the hole transport material.

[0014] In one embodiment, R2 is selected from a hydrocarbon group, wherein the number of carbon atoms in the hydrocarbon group is 0-16; or, R2 is selected from a heteroatom-substituted hydrocarbon group, wherein the total number of heteroatoms and carbon atoms is 0-16, and the heteroatoms include one or more of oxygen atoms and sulfur atoms. When the number of R2 atoms is within the above range, it is possible to reduce the interaction force between the hole transport material and the quantum dot while maintaining the carrier transport performance of the hole transport material.

[0015] In one embodiment, R2 is selected from hydrocarbon groups, and in the structure shown in formula (1), the total number of oxygen atoms in the R1 substituents is less than or equal to 6; or, R2 is selected from heteroatom-substituted hydrocarbon groups, and in the structure shown in formula (1), the total number of heteroatoms in the R1 substituents is less than or equal to 6. With the above configuration, the solubility of the hole transport material in alcohol solvents can be reduced, and the damage to the hole transport material by the alcohol solvent is reduced when the hole transport layer comes into contact with the alcohol solvent.

[0016] In one embodiment, R2 is selected from hydrocarbon groups, and one or more alkoxy groups are connected to R2 as terminal groups. This configuration further reduces the solubility of the hole transport material in alcohol solvents, minimizing the damage caused by alcohol solvents to the hole transport material when the hole transport layer comes into contact with them.

[0017] In one embodiment, the hydrocarbon group includes any one of alkane, olefin, and aromatic hydrocarbon groups. This expands the range of optional hole transport materials.

[0018] In one embodiment, R2 further includes one or more substituents R4, including cyano groups. R4 is a highly polar group, which can further increase the polarity of R1 and reduce the interaction force between the hole transport material and the quantum dot.

[0019] In one embodiment, R1 includes the following structural formula and its derivatives:

[0020] When R1 includes the above structure and its derivatives, hydroxyl groups are introduced on the periphery of the hole transport material, which reduces the interaction force between the hole transport material and the quantum dots, reduces the residue of quantum dots during development, improves color mixing problems, and enhances color accuracy.

[0021] In one embodiment, in In the figure, the R1 substituent is attached to the nitrogen atom at position 9; and / or in ... In this configuration, one or two R1 substituents are attached to the carbon atom at position 9; and / or in... In this case, the R1 substituent is attached to at least one of the carbon atoms at the 2, 3, or 4 positions of the non-polymerized benzene ring.

[0022] By introducing hydroxyl groups on the periphery of the hole transport material, the interaction force between the hole transport material and the quantum dots is reduced, the quantum dots remain during development, the color mixing problem is improved, and the color accuracy is enhanced.

[0023] In one embodiment, Ar1, Ar2, and Ar3 may also have at least one substituent R5 and / or R6; R5 includes any one of alkyl substituents and aryl substituents; R6 has the chemical formula -R7-R8, where R7 is selected from hydrocarbon groups with 0-16 carbon atoms, and R8 includes cyano groups. Through the above configuration, substituents R5 and / or R6 can cooperate with R1 to adjust the affinity between the hole transport material and quantum dots, thereby improving the adaptability of the hole transport material.

[0024] In one embodiment, the hole transport material comprises a polymer with the following structure:

[0025]

[0026]

[0027]

[0028]

[0029] The values ​​of i, m, and n range from 0.05 to 0.95.

[0030] The alkyl groups in the hole transport materials mentioned above have high polarity, resulting in a smaller interaction force between the alkyl chain and the alkyl groups, which helps to reduce the residue of quantum dots during development.

[0031] To address the aforementioned technical problems, another technical solution adopted in this application is to provide a light-emitting device, which includes a hole transport layer comprising the hole transport material described in any of the preceding claims. The light-emitting device possesses at least the same advantages as the hole transport material.

[0032] In one embodiment, the light-emitting device includes an anode, a hole transport layer, an emitting layer, an electron transport layer, and a cathode, which are sequentially stacked. The emitting layer includes a quantum dot luminescent material. The light-emitting device has at least the same advantages as hole transport materials.

[0033] To address the aforementioned technical problems, another technical solution adopted in this application is to provide a display panel comprising the light-emitting device described in any of the above claims. The display panel possesses at least the same advantages as the light-emitting device.

[0034] To solve the aforementioned technical problems, another technical solution adopted in this application is to provide a display device, including the aforementioned display panel. The display device has at least the same advantages as the display panel.

[0035] The above description is only an overview of the technical solution of this application. In order to better understand the technical means of this application and to implement it in accordance with the contents of the specification, and to make the above and other objects, features and advantages of this application more obvious and understandable, the following are specific embodiments of this application. Attached Figure Description

[0036] To more clearly illustrate the technical solutions in the embodiments of this application, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of this application. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0037] Figure 1 A schematic diagram of the chemical structure of the hole transport material provided in this application;

[0038] Figure 2 This is a schematic diagram of a light-emitting device in the prior art;

[0039] Figure 3 This is a schematic diagram of a light-emitting device according to one or more embodiments of this application;

[0040] Figure 4 This is a schematic diagram of the structure of a light-emitting device according to one or more embodiments of this application;

[0041] Figure 5 The nuclear magnetic resonance spectrum of the hole transport material in Embodiment 1 of this application;

[0042] Figure 6The nuclear magnetic resonance spectrum of the hole transport material in Embodiment 2 of this application;

[0043] Figure 7 The nuclear magnetic resonance spectrum of the hole transport material in Embodiment 3 of this application;

[0044] Figure 8 The nuclear magnetic resonance spectrum of the hole transport material in Embodiment 4 of this application;

[0045] Figure 9 The nuclear magnetic resonance spectrum of the hole transport material in Embodiment 5 of this application;

[0046] Figure 10 The nuclear magnetic resonance spectrum of the hole transport material in Embodiment 6 of this application;

[0047] Figure 11 The nuclear magnetic resonance spectrum of the hole transport material in Embodiment 7 of this application;

[0048] Figure 12 The nuclear magnetic resonance spectrum of the hole transport material in Embodiment 8 of this application;

[0049] Figure 13 This is the nuclear magnetic resonance spectrum of the hole transport material of Embodiment 9 of this application.

[0050] In the attached image:

[0051] 100. Light-emitting device; 11. Anode; 12. Cathode; 21. Hole transport layer; 22. Electron transport layer; 30. Light-emitting layer. Detailed Implementation

[0052] The embodiments of the technical solution of this application will now be described in detail with reference to the accompanying drawings. These embodiments are only used to more clearly illustrate the technical solution of this application and are therefore merely examples, and should not be used to limit the scope of protection of this application.

[0053] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application pertains; the terminology used herein is for the purpose of describing particular embodiments only and is not intended to limit the application; the terms “comprising” and “having”, and any variations thereof, in the specification, claims, and foregoing description of the drawings are intended to cover non-exclusive inclusion.

[0054] In the description of the embodiments of this application, technical terms such as "first" and "second" are used only to distinguish different objects and should not be construed as indicating or implying relative importance or implicitly specifying the number, specific order, or primary and secondary relationship of the indicated technical features. In the description of the embodiments of this application, "multiple" means two or more, unless otherwise explicitly defined.

[0055] In this document, the term "embodiment" means that a particular feature, structure, or characteristic described in connection with an embodiment may be included in at least one embodiment of this application. The appearance of this phrase in various places throughout the specification does not necessarily refer to the same embodiment, nor is it a separate or alternative embodiment mutually exclusive with other embodiments. It will be explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.

[0056] In the description of the embodiments in this application, the term "and / or" is merely a description of the relationship between related objects, indicating that three relationships can exist. For example, A and / or B can represent: A existing alone, A and B existing simultaneously, and B existing alone. Additionally, the character " / " in this document generally indicates that the preceding and following related objects have an "or" relationship.

[0057] In the description of the embodiments of this application, the term "multiple" refers to two or more (including two), similarly, "multiple sets" refers to two or more (including two sets), and "multiple pieces" refers to two or more (including two pieces).

[0058] As a crucial component of information technology and the terminal human-machine interface of the information chain, displays are applied across various aspects of daily life, including industry, transportation, communications, education, aerospace, satellite remote sensing, entertainment, and healthcare, making them a vital pillar of the information industry. Over the years, display technology has continuously evolved, resulting in various technologies such as liquid crystal displays (LCDs), organic light-emitting diode displays (OLEDs), and quantum dot light-emitting diode displays (QLEDs).

[0059] QLED technology boasts advantages such as high color gamut, long potential lifespan, good viewing angle, and low cost, making it a highly promising future display technology. From a color gamut perspective, due to its extremely narrow half-width and size-adjustable emission wavelength, QLED offers a high color gamut, better presenting natural colors. Regarding contrast, because QLED is a self-emissive technology, it significantly outperforms traditional passively illuminated LCD technologies. In terms of product form, QLED technology allows for ultra-thin and flexible designs. From an energy consumption perspective, QLED technology consumes less energy than LCD and OLED technologies.

[0060] Photolithography is a structural process that uses selective irradiation of photosensitive materials to fabricate complex, high-resolution semiconductor devices over large areas with high precision. It is a particularly useful technique in the fabrication of QLED devices. The photolithography process for QLED devices involves a photoresist development step to remove unwanted quantum dot material from the non-display areas. In QLED devices, the quantum dot emitting layer is typically fabricated on the hole transport layer. Currently, the hole transport material in QLED devices usually has alkyl chains attached to it to improve its solubility in non-polar solvents. Simultaneously, the ligands surrounding the quantum dots generally contain a large number of alkyl chains. Therefore, the van der Waals forces between the quantum dot ligands and the hole transport material are relatively strong. During photolithography development, unwanted quantum dots may remain on the hole transport material, resulting in development residue. Please refer to [link to relevant documentation]. Figure 2 , Figure 2 This is a schematic diagram of a light-emitting device in the prior art. Figure 2 In this process, the hole transport material used is (TFB) In this scheme, quantum dot material residue will remain in the non-display area after development, resulting in color mixing in the display.

[0061] Based on this, this application provides a hole transport material, comprising a compound as shown in formula (1) or a polymer with a structure as shown in formula (1):

[0062]

[0063] Ar1, Ar2, and Ar3 are selected from any one of carbazole and its derivatives, fluorene and its derivatives, and triphenylamine and its derivatives, respectively; the values ​​of i, m, and n are in the range of 0-1, and i+m+n=1; at least one of Ar1, Ar2, and Ar3 has a substituent R1, and R1 contains at least one alkyl group.

[0064] Among Ar1, Ar2, and Ar3, carbazole has the chemical formula […]. Fluorene, chemical formula is Triphenylamine, chemical formula is Derivatives refer to more complex products derived from a simple compound by replacing hydrogen atoms or groups of atoms with other atoms or groups of atoms. In the above embodiments, these are products derived from the substitution of hydrogen atoms in carbazole, fluorene, and triphenylamine by other atoms or groups of atoms. By selecting at least one of carbazole and its derivatives, fluorene and its derivatives, and triphenylamine and its derivatives as the core structure of the hole transport material, the hole transport material can have a high hole mobility, which is beneficial for balancing carrier transport in electroluminescent devices. Furthermore, when the hole transport material is a polymer, it is less susceptible to solvent erosion of the hole transport layer in the light-emitting device.

[0065] In equation (1), i, m, and n represent the molar percentages of Ar1, Ar2, and Ar3 in the polymer, which can be adjusted according to different application requirements. In one embodiment, any one of i, m, and n is 1, and the other two are 0. In this case, the compound molecule contains only one of carbazole and its derivatives, fluorene and its derivatives, and triphenylamine and its derivatives. In one embodiment, any one of i, m, and n is 0, and the other two are not 0. In this case, the compound molecule contains any two of carbazole and its derivatives, fluorene and its derivatives, and triphenylamine and its derivatives. In one embodiment, all of i, m, and n are not 0. In this case, the compound molecule contains carbazole and its derivatives, fluorene and its derivatives, and triphenylamine and its derivatives simultaneously. Preferably, at most one of i, m, and n is 0, that is, the compound molecule contains at least two of carbazole and its derivatives, fluorene and its derivatives, and triphenylamine and its derivatives. In this case, both the hole transport performance and film formation performance of the hole transport material can be taken into account.

[0066] In one embodiment, the values ​​of i, m, and n range from 0.05 to 0.95. In this case, the values ​​of i, m, and n are all non-zero, and the compound molecule shown in equation (1) simultaneously contains distinct Ar1, Ar2, and Ar3. This configuration improves the carrier transport and injection performance of the hole transport material.

[0067] In the above embodiments, at least one of Ar1, Ar2, and Ar3 contains a substituent R1, and R1 contains at least one alkyloxy group. The alkyloxy group (-OR) includes one or more of alkoxy, aryloxy, and olefinoxy groups; for example, the alkyloxy group can be -O-CH3, ... This expands the range of selectable hole transport materials.

[0068] The quantum dot ligands contain numerous alkyl chains with low polarity, while the alkyl groups are highly polar. Therefore, a repulsive force exists between the alkyl chains and the alkyl groups. By introducing alkyl groups around the hole transport material, the interaction force between the hole transport material and the quantum dots is reduced, which can decrease quantum dot residue during development, improve color mixing, and enhance color accuracy. Please refer to [link to relevant documentation]. Figure 3 , Figure 3 This is a schematic diagram of a light-emitting device according to one or more embodiments of this application. As can be seen from the figure, the development residue is significantly reduced after the photolithography and development steps.

[0069] In one embodiment, the hole transport material comprises a polymer with the following structure: Wherein, Ar1 is selected from carbazole and its derivatives, and Ar2 is selected from fluorene and its derivatives; the values ​​of i and m range from 0.05 to 0.95, respectively; Ar1 ​​has a substituent R1; or Ar2 has a substituent R1; or both Ar1 and Ar2 have a substituent R1.

[0070] In one embodiment, the hole transport material comprises a polymer with the following structure: Wherein, Ar1 is selected from carbazole and its derivatives, and Ar3 is selected from triphenylamine and its derivatives; the values ​​of i and n range from 0.05 to 0.95, respectively; Ar1 ​​has a substituent R1; or Ar3 has a substituent R1; or both Ar1 and Ar3 have a substituent R1.

[0071] In one embodiment, the hole transport material comprises a polymer with the following structure: Wherein, Ar1 is selected from carbazole and its derivatives, Ar2 is selected from fluorene and its derivatives, and Ar3 is selected from triphenylamine and its derivatives, and the connection order of Ar1, Ar2, and Ar3 is variable; the values ​​of i, m, and n range from 0.05 to 0.95, respectively; Ar1 ​​has a substituent R1, or Ar2 has a substituent R1, or Ar3 has a substituent R1, or both Ar1 and Ar2 have a substituent R1, or both Ar1 and Ar3 have a substituent R1, or both Ar2 and Ar3 have a substituent R1, or all of Ar1, Ar2, and Ar3 have a substituent R1.

[0072] In the above embodiments, the hole transport materials all contain carbazole and its derivatives. At this time, the material is more rigid, has less electron delocalization in the LUMO (lowest unoccupied molecular orbital) energy level, and even less electron cloud distribution delocalization, which can effectively block electrons.

[0073] In the technical solution provided in this application, by designing the structure of the parent core and substituent R1, the interaction force between the hole transport material and the quantum dot can be reduced, and the quantum dot residue during development can be reduced; at the same time, the solubility of the hole transport material in nonpolar solvents and the carrier transport and injection performance of the hole transport material are taken into account.

[0074] When the structure shown in equation (1) is polymerized as repeating units, polymers with different degrees of polymerization can be obtained. In one embodiment, the number-average molecular weight of the polymer is 10,000-100,000. Hole transport materials with the above-mentioned number-average molecular weight form more uniform films and have better film repeatability.

[0075] In one embodiment, the chemical formula of R1 is -R2-(OR3). a , where 'a' is an integer greater than or equal to 1, -(OR3) a It is an alkoxy group, and one or more alkoxy groups are connected to R2 as terminal groups or branched groups.

[0076] In this group, 'a' can be 1, 2, 3, 4, 5, etc. In alkoxy-OR3, the oxygen atom is bonded to R3, and R3 is an alkyl group, which is a chain-like organic group containing only carbon and hydrogen atoms, such as methyl, ethyl, propyl, isopropyl, cyclopropane, etc.

[0077] R2 is the part of R1 other than the alkoxy group. The alkoxy group (-OR3) can be attached to R2 as a terminal group, for example, when R1 is... When a = 1, the methoxy group is attached to the n-heptyl group of R2 as a terminal group. When the alkoxy group -OR3 is attached to R2 as a terminal group, for example, R1 is... When a = 2, R² is Two methoxy-O-CH3 groups are attached to R2 as terminal groups.

[0078] The alkoxy group -OR3 can be linked to R2 as a branched group, for example, R1 is... When a = 1, the methoxy group is linked to the n-heptyl group as a branched group. When the alkoxy group -OR3 is linked to R2 as a branched group, the interaction force between the quantum dot and the alkyl group inside the hole transport material can be reduced through steric hindrance, further improving the problem of development residue.

[0079] In one embodiment, R2 is selected from a hydrocarbon group, wherein the number of carbon atoms in the hydrocarbon group is 0-16; or, R2 is selected from a heteroatom-substituted hydrocarbon group, wherein the total number of heteroatoms and carbon atoms is 0-16, and the heteroatoms include one or more of oxygen atoms and sulfur atoms.

[0080] A hydrocarbon group is a group formed by removing one or more hydrogen atoms from a hydrocarbon compound composed of carbon and hydrogen atoms. It includes saturated and unsaturated hydrocarbon groups. Heteroatom-substituted hydrocarbon groups are structures where some carbon atoms in the hydrocarbon chain are replaced by heteroatoms. When R2 is selected from hydrocarbon groups with 0-16 carbon atoms, R2 can be... When R2 is selected from a heteroatom-substituted hydrocarbon group, R2 can be... wait.

[0081] In the above embodiment, one end of R2 is connected to... The other end of R2 is connected to an alkoxy group (OR3). a Connection. When the number of carbon atoms in the hydrocarbon group is 0, or when the sum of the number of heteroatoms and carbon atoms in a heteroatom-substituted hydrocarbon group is 0, it refers to alkoxy-(OR3). a It can be directly used as a substituent R1 to connect with at least one of Ar1, Ar2, and Ar3.

[0082] When the number of atoms in R2 is within the aforementioned range, it can reduce the interaction force between the hole transport material and the quantum dot while maintaining the carrier transport performance of the hole transport material. Furthermore, when R2 contains heteroatoms, it can further increase the polarity of the substituent R1, reducing the interaction force between the hole transport material and the quantum dot, thereby further reducing quantum dot residue during development, improving color mixing issues, and enhancing color accuracy.

[0083] In one embodiment, the heteroatom is preferably an oxygen atom. Oxygen atoms have greater polarity, thus resulting in a stronger repulsion between the hole transport material and the quantum dot ligand, which is more conducive to reducing development residue.

[0084] In one embodiment, R2 is selected from hydrocarbon groups, and in the structure shown in formula (1), the total number of oxygen atoms in the R1 substituents is less than or equal to 6; or, R2 is selected from heteroatom-substituted hydrocarbon groups, and in the structure shown in formula (1), the total number of heteroatoms in the R1 substituents is less than or equal to 6. With the above configuration, the solubility of the hole transport material in alcohol solvents can be reduced, and the damage to the hole transport material by the alcohol solvent is reduced when the hole transport layer comes into contact with the alcohol solvent. For example, in the subsequent preparation of the electron transport layer (which can be a ZnO film), the erosion of the hole transport material by the alcohol solvent is reduced.

[0085] In one embodiment, R2 is selected from a hydrocarbon group, and one or more alkoxy groups are connected to R2 as terminal groups. The total number of oxygen atoms in the R1 substituents is less than or equal to 6. That is, the R1 substituents do not contain oxygen atoms internally, contain alkoxy groups at the ends, and have a small number of oxygen atoms. This can further reduce the solubility of the hole transport material in alcohol solvents, and reduce the damage of the hole transport material to the alcohol solvent when the hole transport layer comes into contact with the alcohol solvent.

[0086] In one embodiment, the hydrocarbon group includes any one of alkane, olefin, and aromatic hydrocarbon groups. This expands the range of optional hole transport materials.

[0087] In one embodiment, R2 further includes one or more substituents R4, wherein R4 includes a cyano (-CN).

[0088] The cyano group (-CN) is a highly polar group, which can further increase the polarity of the substituent R1, enhance the mutual repulsion between the hole transport material and the quantum dot, thereby further reducing the residual quantum dot during development, improving color mixing problems, and increasing color accuracy.

[0089] In one embodiment, R1 includes the following structural formula and its derivatives:

[0090]

[0091] In the aforementioned structures of R1 and its derivatives, the left side of R1 is... Connection. Among them, the derivatives of R1 have three meanings: first, the carbon chain or molecular chain containing heteroatoms of R1 can be extended, for example... Derivatives include Secondly, the R2 portion of R1 may also include one or more substituents R4, where R4 includes a cyano group (-CN), for example... Derivatives include Etc.; thirdly, R1 can also have other branches, for example... Derivatives include wait.

[0092] When R1 includes the above structures and their derivatives, hydroxyl groups are introduced into the periphery of the hole transport material, which reduces the interaction force between the hole transport material and the quantum dots, reduces the residue of quantum dots during development, improves color mixing problems, and enhances color accuracy. At the same time, the hole transport material has a variety of structures, which can be selected according to different application requirements.

[0093] In one embodiment, the substituent R1 is located in carbazole In the case of carbazole and its derivatives, the substitution position of R1 can be the carbon atoms at positions 1-8 and the nitrogen atom at position 9. When other substituents are present on carbazole, the substitution position of R1 avoids the substitution positions of other substituents.

[0094] Preferably, the R1 substituent is attached to the nitrogen atom at position 9, i.e.

[0095] In one embodiment, the substituent R2 is located in fluorene. In fluorene and its derivatives, the substitution position of R1 can be any carbon atom from position 1 to 9 of fluorene. When other substituents are present on fluorene, the substitution position of R1 avoids the substitution positions of those other substituents.

[0096] Preferably, one or both of the R1 substituents are attached to the carbon atom at position 9, i.e. Among them, multiple R1s can be substituents with the same structure or substituents with different structures.

[0097] In one embodiment, the substituent R2 is located on triphenylamine. In the case of triphenylamine and its derivatives, the substitution position of R1 can be the carbon atoms at positions 1-5 of the non-polymerized benzene ring. When other substituents are present on the non-polymerized benzene ring of triphenylamine, the substitution position of R1 avoids the substitution positions of those other substituents. Here, the non-polymerized benzene ring of triphenylamine refers to the ring that does not participate in the polymerization process. The benzene ring with intermediate bonding.

[0098] Preferably, the R1 substituent is attached to at least one of the carbon atoms at positions 2, 3, and 4 of the non-polymerized benzene ring of triphenylamine, for example, it can be... etc. Among them, multiple R1s can be substituents with the same structure or substituents with different structures.

[0099] By introducing hydroxyl groups on the periphery of the hole transport material, the interaction force between the hole transport material and the quantum dots is reduced, the quantum dots remain during development, the color mixing problem is improved, and the color accuracy is enhanced.

[0100] In one embodiment, when there are multiple R1 substituents, the structures of the multiple R1 substituents may be the same or different.

[0101] When there are multiple R1 substituents in the compound shown in formula (1), the structures of the multiple R1 substituents can be completely the same; or some of the R1 substituents can have the same structure, while the structures of the other R1 substituents can be different; or multiple R1 substituents on the same parent nucleus can have the same structure, while R1 substituents on different parent nuclei can be different; or the structures of the multiple R1 substituents can all be different.

[0102] In some implementations, Ar1, Ar2, and Ar3 may also have other substituents besides the R1 substituent.

[0103] In one embodiment, Ar1, Ar2, and Ar3 may also have at least one substituent R5 and / or R6.

[0104] R5 includes any one of alkyl substituents and aryl substituents.

[0105] The chemical formula for R6 is -R7-R8, where R7 is selected from hydrocarbon groups with 0-16 carbon atoms, and R8 includes cyano groups.

[0106] When substituent -R5 is an alkyl substituent, it can be methyl, ethyl, propyl, isopropyl, etc.; when substituent -R5 is an aryl substituent, it can be phenyl. benzyl Methylphenyl The lower polarity of substituent R5 is beneficial for improving the solubility of hole transport materials in nonpolar solvents; at the same time, it works in conjunction with substituent R1 to adjust the affinity between hole transport materials and quantum dots, thereby improving the adaptability of hole transport materials.

[0107] In the substituent -R6, -R8 includes a cyano group (-CN). These groups are highly polar, which can further increase the polarity of the hole transport material, reduce the interaction force between the hole transport material and the quantum dot, thereby further reducing the quantum dot residue during development, improving color mixing problems, and enhancing color accuracy.

[0108] -R7 is selected from hydrocarbon groups with 0-16 carbon atoms, which can reduce the interaction force between hole transport materials and quantum dots while taking into account the carrier transport performance of hole transport materials.

[0109] In one embodiment, the hole transport material comprises a polymer with the following structure:

[0110]

[0111]

[0112]

[0113] The values ​​of i, m, and n range from 0.05 to 0.95.

[0114] The hydroxyl groups in the aforementioned hole transport materials are highly polar, resulting in weak interaction between the alkyl chains and the hydroxyl groups. By introducing hydroxyl groups onto the periphery of the hole transport material, the interaction between the hole transport material and the quantum dots is reduced, decreasing quantum dot residue during development, thus improving color mixing and enhancing color accuracy.

[0115] Furthermore, hole transport materials containing cyano groups and other polar substituents exhibit enhanced polarity, which can further reduce the interaction force between the hole transport material and the quantum dot.

[0116] This application also provides a light-emitting device, which includes a hole transport layer, and the hole transport layer includes the hole transport material described above.

[0117] Please see Figure 4 , Figure 4 This is a schematic diagram of a light-emitting device according to one or more embodiments. In one embodiment, the light-emitting device 100 includes an anode 11, a hole transport layer 21, a light-emitting layer 30, an electron transport layer 22, and a cathode 12 stacked sequentially, wherein the light-emitting layer includes a quantum dot light-emitting material.

[0118] The interaction force between the hole transport layer and the quantum dot material is relatively small. During the process of fabricating light-emitting devices using photolithography, it can reduce the residue of quantum dots in the hole transport layer during development, improve the color mixing problem of light-emitting devices, and enhance color accuracy.

[0119] In one embodiment, the light-emitting device 100 further includes a hole injection layer (not shown) located between the anode and the hole transport layer.

[0120] This application also provides a display panel, including the aforementioned light-emitting device 100. The display panel has high color accuracy.

[0121] This application also provides a display device, including the aforementioned display panel.

[0122] Display devices can be any product or component with a display function, such as mobile phones, tablets, televisions, monitors, laptops, digital photo frames, and navigators.

[0123] The beneficial effects of this application are further illustrated below with reference to the embodiments.

[0124] To make the technical problems, technical solutions, and beneficial effects solved by the embodiments of this application clearer, the following will provide a more detailed description in conjunction with the embodiments and accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of this application, and not all of them. The following description of at least one exemplary embodiment is merely illustrative and is in no way intended to limit this application or its applications. Based on the embodiments of this application, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of this application.

[0125] I. Synthesis and Characterization of Hole Transport Materials:

[0126] 1. Synthesis of Hole Transport Materials in Example 1

[0127] (1) 1 mmol of 2,7-dibromofluorene and 1.2 mmol of p-toluenesulfonyl glycol monomethyl ether were placed in a three-necked flask, followed by 10 mL of 50% NaOH aqueous solution and 5 mmol of tetrabutylammonium bromide. Toluene was added, and the mixture was heated to 60 °C and stirred for 12 h. The reaction solution was separated by extraction and column chromatography to obtain compound 1.

[0128] (2) Take 1 mmol of compound 1 and dissolve it in tetrahydrofuran. Replace it with a nitrogen atmosphere, cool it to -78°C, add 1.2 mmol of n-butyllithium, react for 2 h, add 2 mmol of trimethylboronic acid dropwise, stir the reaction to room temperature, add hydrochloric acid to quench, and extract the mixture to obtain compound 2.

[0129] (3) Take 1 mmol of compound 2, 1.05 mmol of compound 3, 0.1 mmol of tetrakis(triphenylphosphine)palladium, and 2 mmol of sodium carbonate (Na2CO3), dissolve them in toluene, heat to 80°C, stir and react for 12 h. After extraction and multiple sedimentation, the hole transport material S1 of Example 1 is obtained, with the smallest repeating unit being... The number-average molecular weight is 28,100, and its nuclear magnetic resonance spectrum is as follows: Figure 5 As shown, the synthesis steps are as follows:

[0130]

[0131] 2. Synthesis of Hole Transport Materials in Example 2

[0132] The steps for synthesizing compound 2 are the same as in Example 1, except that:

[0133] (3) Take 1 mmol of compound 2, 1.05 mmol of compound 4, 0.1 mmol of tetrakis(triphenylphosphine)palladium, and 2 mmol of sodium carbonate (Na2CO3), dissolve them in toluene, heat to 80°C, stir and react for 12 h. After extraction and multiple sedimentation, the hole transport material S2 of Example 2 is obtained, with the smallest repeating unit being... The number-average molecular weight is 32,000, and its nuclear magnetic resonance spectrum is as follows: Figure 6 As shown, the synthesis steps are as follows:

[0134]

[0135] 3. Synthesis of Hole Transport Materials in Example 3

[0136] The steps for synthesizing compound 2 are the same as in Example 1, except that:

[0137] (3) Take 1 mmol of compound 2, 0.55 mmol of compound 3, 0.55 mmol of compound 4, and 0.1 mmol of tetrakis(triphenylphosphine)palladium, and 2 mmol of sodium carbonate (Na2CO3), dissolve them in toluene, heat to 80°C, and stir for 12 h. After extraction and multiple sedimentation, the hole transport material S3 of Example 3 is obtained, with the smallest repeating unit being... The number-average molecular weight is 53,100, and its nuclear magnetic resonance spectrum is as follows: Figure 7 As shown, the synthesis steps are as follows:

[0138]

[0139] 4. Synthesis of Hole Transport Materials in Example 4

[0140] The steps for synthesizing compound 2 are the same as in Example 1, except that:

[0141] (3) Take 1 mmol of compound 2, 1.05 mmol of compound 5, 0.1 mmol of tetrakis(triphenylphosphine)palladium, and 2 mmol of sodium carbonate (Na2CO3), dissolve them in toluene, heat to 80°C, stir and react for 12 h. After extraction and multiple sedimentation, the hole transport material S4 of Example 4 is obtained, with the smallest repeating unit being... The number-average molecular weight is 31,600, and its nuclear magnetic resonance spectrum is as follows: Figure 8 As shown, the synthesis steps are as follows:

[0142]

[0143] 5. Synthesis of Hole Transport Materials in Example 5

[0144] The steps for synthesizing compound 2 are the same as in Example 1, except that:

[0145] (3) Take 1 mmol of compound 6, 1.05 mmol of compound 7, 0.1 mmol of tetrakis(triphenylphosphine)palladium, and 2 mmol of sodium carbonate (Na2CO3), dissolve them in toluene, heat to 80°C, stir and react for 12 h. After extraction and multiple sedimentation, the hole transport material S5 of Example 5 is obtained, with the smallest repeating unit being... The number-average molecular weight is 43,600, and its nuclear magnetic resonance spectrum is as follows: Figure 9 As shown, the synthesis steps are as follows:

[0146]

[0147] 6. Synthesis of Hole Transport Materials in Example 6

[0148] The steps for synthesizing compound 2 are the same as in Example 1, except that:

[0149] (3) Take 1 mmol of compound 6, 1.05 mmol of compound 8, 0.1 mmol of tetrakis(triphenylphosphine)palladium, and 2 mmol of sodium carbonate (Na2CO3), dissolve them in toluene, heat to 80°C, stir and react for 12 h. After extraction and multiple sedimentation, the hole transport material S6 of Example 6 is obtained, with the smallest repeating unit being... The number-average molecular weight is 38,400, and its nuclear magnetic resonance spectrum is as follows: Figure 10 As shown, the synthesis steps are as follows:

[0150]

[0151] 7. Synthesis of Hole Transport Materials in Example 7

[0152] The steps for synthesizing compound 2 are the same as in Example 1, except that:

[0153] (3) Take 1 mmol of compound 9, 1.05 mmol of compound 8, 0.1 mmol of tetrakis(triphenylphosphine)palladium, and 2 mmol of sodium carbonate (Na2CO3), dissolve them in toluene, heat to 80°C, stir and react for 12 h. After extraction and multiple sedimentation, the hole transport material S7 of Example 7 is obtained, with the smallest repeating unit being... The number-average molecular weight is 36,900, and its nuclear magnetic resonance spectrum is as follows: Figure 11 As shown, the synthesis steps are as follows:

[0154]

[0155] 8. Synthesis of Hole Transport Materials in Example 8

[0156] The steps for synthesizing compound 2 are the same as in Example 1, except that:

[0157] (3) Take 1 mmol of compound 10, 1.05 mmol of compound 11, 0.1 mmol of tetrakis(triphenylphosphine)palladium, and 2 mmol of sodium carbonate (Na2CO3), dissolve them in toluene, heat to 80°C, stir and react for 12 h. After extraction and multiple sedimentation, the hole transport material S8 of Example 5 is obtained, with the smallest repeating unit being... The number-average molecular weight is 23600, and its nuclear magnetic resonance spectrum is as follows: Figure 12 As shown, the synthesis steps are as follows:

[0158]

[0159] 9. Synthesis of Hole Transport Materials in Example 9

[0160] The steps for synthesizing compound 2 are the same as in Example 1, except that:

[0161] (3) Take 1 mmol of compound 12, 1.05 mmol of compound 13, 0.1 mmol of tetrakis(triphenylphosphine)palladium, and 2 mmol of sodium carbonate (Na2CO3), dissolve them in toluene, heat to 80°C, stir and react for 12 h. After extraction and multiple sedimentation, the hole transport material S9 of Example 9 is obtained, with the smallest repeating unit being... The number-average molecular weight is 22300, and its nuclear magnetic resonance spectrum is as follows: Figure 13 As shown, the synthesis steps are as follows:

[0162]

[0163] 10. Analysis of the nuclear magnetic resonance spectra of hole transport materials in Examples 1-9

[0164] (1) Example 1

[0165] Please see Figure 5 1H NMR spectrum 1 ¹H NMR (test frequency 300 MHz, sample solvent dimethyl sulfoxide DMSO): chemical shift δ = 8.09 (d, J = 2.3 Hz, 1H), 7.89–7.90 (d, 2H), 7.78 (d, J = 2.6 Hz, 1H), 7.55 (d, J = 1.9 Hz, 2H), 7.38 (s, 1H), 7.00–7.27 (d, 11H), 3.52–3.55 (t, 8H), 3.35–3.40 (m, 10H), 2.55 (t, 1H), 2.02 (s, 4H), 1.52 (s, 2H), 1.16 (t, 3H), 0.76 (t, 3H).

[0166] (2) Example 2

[0167] Please see Figure 6 , 1 H NMR (300MHz, DMSO: δ=8.86(d,J=3.3Hz,1H),8.19-8.22(t,J=2.5Hz,2H),8.09(d,J=2.3Hz,1H),7.89-7.90(d,2H) ,7.74-7.78(d,J=2.6Hz,2H),7.20-7.58(d,8H),3.52-3.55(t,8H),3.35-3.40(m,10H),2.02(s,4H),1.33(t,9H).

[0168] (3) Example 3

[0169] Please see Figure 7 , 1 H NMR (300MHz, DMSO): δ=8.86 (d, J=3.3Hz, 1H), 8.19-8.22 (t, J=2.5Hz, 2H), 8.09 (d, J=2.3Hz, 1H), 7.89-7.90 (d, 2H), 7.74-7.78 (d, J=2.6Hz, 2 H),7.06-7.58(d,18H),3.52-3.55(t,8H),3.35-3.40(m,10H),2.55(t ,1H),2.02(s,4H),1.52(s,2H),1.33(t,9H)1.16(t,3H),0.76(t,3H).

[0170] (4) Example 4

[0171] Please see Figure 8 , 1 H NMR (300MHz, DMSO): δ=8.86 (d, J=3.3Hz, 1H), 8.19-8.22 (t, J=2.5Hz, 2H), 8.09 (d, J=2.3Hz, 1H), 7.89-7.91 (d,4H),7.74-7.78(d,J=2.6Hz,3H),7.20-7.58(d,4H),3.52-3.55(t,8H),3.35-3.40(m,10H),2.02(s,4H).

[0172] (5) Example 5

[0173] Please see Figure 9 , 1H NMR (300MHz, DMSO): δ = 8.86 (d, J = 3.3Hz, 1H), 8.19-8.22 (t, J = 2.5Hz, 2H), 8.09 (d, J = 2.3Hz, 1H), 7.89-7.90 (d, 2H), 7.74-7.78 (d, J = 2.6Hz, 2H) ,7.20-7.58(d,4H),6.68(d,J=6.3Hz,2H),6.35(d,J=6.34Hz,1H),3.81 (s,6H), 3.77(s,1H).3.52-3.55(t,4H),3.35-3.40(m,5H),2.02(s,2H).

[0174] (6) Example 6

[0175] Please see Figure 10 , 1 H NMR (300MHz, DMSO): δ=8.09(d,J=2.3Hz,1H),7.89-7.90(d,2H),7.78(d,J=2.6Hz,1H),7.55(d,J=1.9Hz,2H),7.38(s,1H),7.00 -7.27(d,7H),6.50(d,J=6.1Hz,2H),3.83(m,6H),3.77(s,1H),3.71(t,3H),3.52-3.55(t,4H),3.35-3.40(m,5H),2.02(s,2H).

[0176] (7) Example 7

[0177] Please see Figure 11 , 1 H NMR (300MHz, DMSO): δ=8.09(d,J=2.3Hz,1H),7.89-7.90(d,2H),7.78(d,J=2.6Hz,1H),7.55(d,J=1.9Hz,2H),7.38(s,1H),7.00 -7.27(d,7H),6.50(d,J=6.1Hz,2H),3.83(m,6H),3.77(s,1H),3.71(t,3H),2.81(s,4H),2.60(m,2H),2.28(s,2H),2.07(s,3H).

[0178] (8) Example 8

[0179] Please see Figure 12 , 1H NMR (300MHz, DMSO): δ=7.23-7.57(d,J=4.6Hz,5H),7.08(d,J=3.2Hz,2H),7.00(d,J=3.7Hz,2H),6.92-6.95(d,J=2.9Hz,3H),6.8 2(d,J=2.9Hz,1H),6.76(d,J=1.9Hz,1H),6.60(d,J=2.2Hz,1H),6.02(s,6H),3.79(s,6H),3.30(s,6H),1.95(m,2H),0.93(t,3H).

[0180] (9) Example 9

[0181] Please see Figure 13 , 1 H NMR (300MHz, DMSO): δ=8.34-8.39(d,J=2.3Hz,2H),8.24(d,J=2.5Hz,1H),7.77(d,J=3.3Hz,1H),7. 57(d,1H),7.51(d,J=2.6Hz,1H),7.34(d,J=2.5Hz1H),7.23(m,J=2.7Hz,1H),7.00-7.14(d,J=3.5Hz 2H),5.00(t,1H),4.16(m,2H),3.79(s,6H),3.52(m,8H),3.46(m,4H),3.35(d,10H),2.02(m,4H),1.74(m,2H),1.57(m,H),1.05(t,6H).

[0182] II. QLED fabrication:

[0183] The hole transport materials S1-S9 prepared in Examples 1-9 were used as the hole transport layers of the QLED devices described below. The specific fabrication steps of the QLEDs are as follows:

[0184] On an indium tin oxide (ITO) substrate (anode), after UV ozone treatment for 5 min, a hole injection layer with a thickness of 40 nm was obtained by spin-coating poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) onto a substrate and annealing at 120 °C for 30 min. Then, a hole transport layer with a thickness of 50 nm was obtained by spin-coating with the hole transport material solution from Examples 1-9 and annealing at 150 °C for 1 h. Finally, a red quantum dot solution was used for spin-coating to target the red light region. The process involves exposure and development with n-octane, followed by spin-coating with a green quantum dot solution. The green region is then exposed and developed with n-octane, and annealed at 100°C for 30 min to obtain a 20 nm thick red quantum dot emitting layer and a 15 nm thick green quantum dot emitting layer. Next, a 50 nm thick electron transport layer is obtained by spin-coating with a zinc oxide (ZnO) solution and annealing at 80°C for 30 min. Finally, a 100 nm thick aluminum (Al) electrode is deposited as the cathode. The resulting light-emitting devices are labeled Q1-Q9.

[0185] Comparative example:

[0186] On an indium tin oxide (ITO) substrate (anode), after UV ozone treatment for 5 min, a hole injection layer with a thickness of 40 nm was obtained by spin-coating poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) and annealing at 120 °C for 30 min. Then, a hole transport layer with a thickness of 50 nm was obtained by spin-coating with TFB solution and annealing at 150 °C for 1 h. Next, a red quantum dot solution was used for spin-coating and developed with n-octane, followed by a green quantum dot solution for spin-coating and development with n-octane, and then annealing at 100 °C for 30 min to obtain a red quantum dot emitting layer with a thickness of 20 nm and a green quantum dot emitting layer with a thickness of 15 nm. Then, a zinc oxide (ZnO) solution was used for spin-coating and annealing at 80 °C for 30 min to obtain an electron transport layer with a thickness of 50 nm. Finally, an aluminum (Al) electrode with a thickness of 100 nm was deposited as the cathode.

[0187] III. Performance Testing of Light-Emitting Devices

[0188] 1. CIE1931

[0189] CIE 1931 refers to a color space standard established by the International Commission on Illumination (CIE) in 1931. It is based on human visual perception of color and describes color using three coordinates: X, Y, and Z. The Z-axis represents luminance, while the X and Y axes provide the chromaticity coordinates. In this case, the X and Y axis values ​​are used to express color accuracy, as shown in Table 1 as coordinates (X, Y). The testing method is as follows: The prepared substrate is placed in a darkroom, and the device is voltage-scanned using an IVL testing system. The changes in chromaticity, luminance, and current with voltage are recorded.

[0190] 2. EQE

[0191] EQE refers to External Quantum Efficiency, which describes the efficiency of an optoelectronic device in converting incident light into current. It is defined as the number of "emitted photons" per unit time converted from the number of injected electrons per unit time. The testing method is as follows: The prepared substrate is placed in a dark room, and the device is voltage-scanned using an IVL testing system. The changes in chromaticity, brightness, and current with voltage are recorded. The tested brightness is the light emitted perpendicular to the emitting plane, and is calculated based on the cosine decay of brightness (Lambertian distribution), combined with the spectrum and input current density.

[0192] The test results are shown in Table 1.

[0193] Table 1 Test parameters for each embodiment and comparative example

[0194]

[0195] IV. Analysis of Performance Test Results of Light-Emitting Devices

[0196] In the CEI1931 test results, for red light, a larger X and a smaller Y indicate a purer color; for green light, a smaller X and a larger Y indicate a purer color. Therefore, compared to Comparative Example 1, the hole transport material provided in Examples 1-4 enables the light-emitting device to exhibit higher color accuracy.

[0197] Meanwhile, in the EQE test results, compared with Comparative Example 1, the hole transport material provided by this application in Examples 1-4 enabled the light-emitting device to exhibit higher external quantum efficiency, indicating that its luminous efficiency has also been improved.

[0198] The above description is merely an embodiment of this application and does not limit the patent scope of this application. Any equivalent structural or procedural transformations made using the content of this application's specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of this application.

Claims

1. A hole transporting material, characterized by, Including compounds as shown in formula (1) or polymers with structures as shown in formula (1): Ar1, Ar2, and Ar3 are selected from any one of carbazole and its derivatives, fluorene and its derivatives, and triphenylamine and its derivatives, respectively. The values ​​of i, m, and n are in the range of 0-1, and i+m+n=1; At least one of Ar1, Ar2, and Ar3 contains a substituent R1, wherein R1 contains at least one alkyl group.

2. The hole transport material as described in claim 1, characterized in that, The number average molecular weight of the polymer is 10,000-100,000.

3. The hole transport material as described in claim 1, characterized in that, The values ​​of i, m, and n range from 0.05 to 0.

95.

4. The hole transport material as described in claim 1, characterized in that, The hydrocarbon oxygen group includes one or more of alkoxy, aryloxy, and olefin oxygen groups.

5. The hole transport material as described in claim 1, characterized in that, said R1 has the formula -R2-(OR3) a , a has a value of an integer greater than or equal to 1, -(OR3) a is an alkoxy group, one or more of said alkoxy groups being attached to R2 as a terminal group or as a branched group.

6. The hole transport material as described in claim 5, characterized in that, The R2 is selected from a hydrocarbon group, wherein the hydrocarbon group has 0-16 carbon atoms; or... R2 is selected from heteroatom-substituted hydrocarbon groups, the total number of heteroatoms and carbon atoms is 0-16, and the heteroatoms include one or more of oxygen atoms and sulfur atoms.

7. The hole transport material as described in claim 6, characterized in that, R2 is selected from hydrocarbon groups, and in the structure shown in formula (1), the total number of oxygen atoms in the R1 substituents is less than or equal to 6; or, R2 is selected from heteroatom-substituted hydrocarbon groups, and in the structure shown in formula (1), the total number of heteroatoms of the R1 substituents is less than or equal to 6.

8. The hole transport material as described in claim 6, characterized in that, The hydrocarbon group includes any one of alkane group, olefin group, and aromatic hydrocarbon group.

9. The hole transport material as described in claim 5, characterized in that, The R2 also includes one or more substituents R4, wherein the R4 includes a cyano group.

10. The hole transport material according to any one of claims 1-9, characterized in that, R1 includes the following structural formulas and their derivatives:

11. The hole transport material as described in claim 1, characterized in that, In In particular, the R1substituent is attached to the nitrogen atom at position 9; and / or exist In this configuration, one or both of the R1 substituents are attached to the carbon atom at position 9; and / or exist In this embodiment, the R1 substituent is attached to at least one of the carbon atoms at the 2, 3, and 4 positions of the non-polymerized benzene ring.

12. The hole transport material as described in claim 1, characterized in that, Ar1, Ar2, and Ar3 may also have at least one substituent R5 and / or R6; R5 includes any one of alkyl substituents and aryl substituents; The chemical formula of R6 is -R7-R8, where R7 is selected from hydrocarbon groups with 0-16 carbon atoms, and R8 includes cyano groups.

13. The hole transport material as described in claim 1, characterized in that, The hole transport material comprises a polymer with the following structure: The values ​​of i, m, and n range from 0.05 to 0.

95.

14. A light-emitting device, characterized in that, The light-emitting device includes a hole transport layer, which includes a hole transport material as described in any one of claims 1-13.

15. The light-emitting device as described in claim 14, characterized in that, The light-emitting device includes an anode, a hole transport layer, a light-emitting layer, an electron transport layer, and a cathode stacked sequentially, wherein the light-emitting layer includes quantum dot light-emitting material.

16. A display panel, characterized in that, Includes the light-emitting device as described in any one of claims 14 or 15.

17. A display device, characterized in that, Includes the display panel as described in claim 16.

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