Quantum dot inks, methods of making and using the same

Abstract

This application relates to the field of electronic display technology, and in particular to a quantum dot ink, its preparation method, and its application. The quantum dot ink comprises the following components by mass percentage: 10%–30% quantum dots, 20%–50% epoxy resin, 10%–20% acrylic resin, 5%–10% scattering particles, 20%–30% active monomer, 0.1%–2% photoinitiator, and 0.1%–1% dispersant; the photoinitiator includes free radical photoinitiators and cationic photoinitiators; the active monomer includes at least one acrylate compound represented by the following formula, where R1 is hydrogen or methyl, R2 is hydrogen, methyl, or ethyl, and n is an integer from 1 to 4. The above-mentioned quantum dot ink exhibits excellent dispersion stability, light extraction efficiency, and light conversion efficiency.

Description

Technical Field

[0001] This application relates to the field of electronic display technology, and in particular to a quantum dot ink, its preparation method, and its application. Background Technology

[0002] Quantum confinement endows quantum dots with excellent luminescent properties, such as broadband absorption, narrowband emission, and continuously tunable peak positions. As a new generation of luminescent and optoelectronic materials, quantum dots are expected to be applied in many fields such as displays and lighting, lasers, single-photon sources, and biomedical imaging. Especially in the display field, commercial quantum dot display products have already been launched.

[0003] The construction of full-color quantum dot displays relies on the precise patterning of red, green, and blue light-emitting units. Currently, photolithography is the primary process for patterning quantum dots to meet the optoelectronic application requirements. However, the exposure and development processes in photolithography significantly impact quantum dots, easily leading to quenching and deactivation. Inkjet printing, as a non-contact, non-photolithographic, high-resolution printing method, presents a promising approach for quantum dot patterning.

[0004] However, most quantum dot inks currently available for inkjet printing are free radical photocurable systems, which often suffer from the following technical problems during preparation: 1. Poor compatibility between quantum dots and photocurable resin systems. Quantum dots are difficult to disperse uniformly in photocurable resins, and during printing, quantum dots and scattering particles are prone to agglomeration, causing printhead clogging; 2. During photocuring, quantum dots absorb and convert some ultraviolet light, affecting the curing effect of the photocurable resin; 3. Because the ink system contains solvents, it needs to be baked before curing to evaporate the solvents, which can cause thermal damage to the performance of quantum dots; 4. Due to ink curing shrinkage or solvent evaporation, the ink sinks inward in the ink bank, reducing light extraction efficiency and even causing light leakage, resulting in uneven color; 5. The absorption rate (OD@450) of the quantum dot color conversion film for blue light is too low. When the thickness of the quantum dot color conversion film is less than 10μm, the OD is much less than 2 (i.e., blue light absorption rate <99%), which cannot guarantee color gamut and color purity, thus making it difficult to achieve high-quality images. The aforementioned defects in quantum dot inks affect the light extraction efficiency and light conversion efficiency of quantum dot color conversion films. Summary of the Invention

[0005] Therefore, it is necessary to provide quantum dot inks, their preparation methods, and applications that can improve the compatibility between quantum dots and the dispersion matrix, and enhance the dispersion stability, light extraction efficiency, and light conversion efficiency of quantum dot inks.

[0006] In a first aspect, this application provides a quantum dot ink comprising the following components by mass percentage:

[0007] Quantum dots 10%–30%, epoxy resin 20%–50%, acrylic resin 10%–20%, scattering particles 5%–10%, active monomers 20%–30%, photoinitiator 0.1%–2%, and dispersant 0.1%–1%;

[0008] The photoinitiator includes free radical photoinitiators and cationic photoinitiators;

[0009] The active monomer includes at least one of the acrylate compounds represented by Formula I:

[0010]

[0011] In Formula I, R1 is hydrogen or methyl, R2 is hydrogen, methyl or ethyl, and n is an integer from 1 to 4.

[0012] In some embodiments, the scattering particles are nano-metal oxides, including one or more of TiO2, ZnO, SnO2, NiO, MoO, Al2O3, CeO2, and ZrO2.

[0013] In some embodiments, the mass ratio of the scattering particle to the organic ligand is 1:(0.2 to 0.3).

[0014] In some embodiments, the average particle size of the scattering particles is 50 nm to 100 nm.

[0015] In some embodiments, the quantum dots and the scattering particles are chemically modified with the same organic ligand, the organic ligand comprising an active group for chemically modifying the quantum dots and the scattering particles, the active group being selected from carboxyl, mercapto, zinc thiol, or amino groups.

[0016] In some embodiments, the epoxy resin has an epoxy equivalent of 150 g / Eg to 300 g / Eg and a number average molecular weight of 5000 to 10000.

[0017] In some embodiments, the epoxy resin includes one or more of alicyclic epoxy resins, phenolic epoxy resins, and glycidyl ether type epoxy resins.

[0018] In some embodiments, in Formula I, R1 is hydrogen or methyl, R2 is hydrogen, methyl or ethyl, and n is 1; preferably, the active monomer includes one or more of hydroxyethyl methacrylate, hydroxypropyl methacrylate and hydroxybutyl methacrylate.

[0019] In some embodiments, the organic ligand is selected from oleylamine, oleic acid, zinc alkylthiolate, polythiol, or ammonium carboxylate.

[0020] In some embodiments, the dispersant includes one or more of BYK163 dispersant, BYK168 dispersant, BYK180 dispersant, BYK110 dispersant, BYK108 dispersant and BYK103 dispersant.

[0021] In some embodiments, one or more of silicon quantum dots, germanium quantum dots, sulfide quantum dots, selenide quantum dots, telluride quantum dots, phosphide quantum dots, arsenide quantum dots, and copper indium sulfide quantum dots are used; the mass ratio of the quantum dots to the organic ligand is 1:(0.2 to 0.3).

[0022] In some embodiments, the acrylic resin has a viscosity of 1 cps to 5 cps and a number-average molecular weight of ≤3000.

[0023] In some embodiments, the free radical photoinitiator includes one or more of the following: benzoin isobutyl ether, benzoin ethyl ether, 2,4-diethyl acetophenone, 2-isopropyl acetophenone, 2,4,6-trimethylbenzoyl phosphate diethyl ester, 2,4,6-trimethylbenzoyl diphenylphosphine oxide, 6-trimethylbenzoyl diphenylphosphine oxide, 2-phenyl-2,2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, methyl o-benzoylbenzoate, phenyl bis(2,4,6-trimethylbenzoyl)phosphine oxide, bis(2,6-dimethoxybenzoyl)-(4,4-dimethyloctyl-2)phosphine oxide, 2,4-diethylthioxanthraquinone, 2-chlorothioxanthraquinone, and 2-ethylanthraquinone.

[0024] In some embodiments, the cationic photoinitiator includes one or more of diaryl ferric iodide, triaryl sulfide and aryl ferrocene, thioonium hexafluorophosphate, thioonium hexafluoroantimonate, and mixed triaryl sulfioonium hexafluoroantimonate.

[0025] In some embodiments, the mass ratio of the radical photoinitiator to the cationic photoinitiator is 1:(1-2).

[0026] Secondly, this application provides a method for preparing the quantum dot ink described above, comprising the following steps:

[0027] Quantum dots, active monomers, and a first dispersant are mixed to form a first dispersion.

[0028] The scattering particles, acrylic resin, and second dispersant are mixed to form a second dispersion.

[0029] Epoxy resin and photoinitiator are mixed to form a third dispersion; and

[0030] Quantum dot ink is prepared by mixing a first dispersion, a second dispersion, and a third dispersion; wherein the quantum dot ink comprises the following components in the following mass percentages: quantum dots 10%–30%, epoxy resin 20%–50%, acrylic resin 10%–20%, scattering particles 5%–10%, active monomers 20%–30%, photoinitiator 0.1%–2%, a first dispersant, and a second dispersant; the total amount of the first dispersant and the second dispersant accounts for 0.1%–1% of the mass percentage of the quantum dot ink; the photoinitiator includes free radical photoinitiators and cationic photoinitiators;

[0031] The active monomer includes at least one of the acrylate compounds represented by Formula I:

[0032]

[0033] In Formula I, R1 is hydrogen or methyl, R2 is hydrogen, methyl or ethyl, and n is an integer from 1 to 4.

[0034] Thirdly, this application provides a quantum dot color conversion film, which is formed by inkjet printing and curing using ink as raw material, wherein the ink includes the quantum dot ink described above.

[0035] Fourthly, this application provides an electroluminescent device comprising the quantum dot color conversion thin film described above.

[0036] Fifthly, this application provides a display device that includes the electroluminescent device described above.

[0037] In the quantum dot ink provided in this application, the scattering particles can alter the optical path of blue light, improving the utilization rate of blue light by the quantum dots. Furthermore, the scattering particles can reduce the transmittance of blue light, thereby improving the color purity of devices such as color conversion films and achieving a higher external quantum efficiency. Moreover, the active monomer can undergo free radical photocuring reactions, and since it contains hydroxyl groups, it can undergo ring-opening polymerization with epoxy resin in a cationic photocuring system. Therefore, under the action of a photoinitiator, the quantum dot ink provided in this application possesses both free radical and cationic photocuring characteristics. It has low curing energy, resulting in low curing volume shrinkage, with the post-curing shrinkage rate reaching below 2%, and exhibits high blue light absorption and external quantum efficiency. Attached Figure Description

[0038] To more clearly illustrate the technical solutions in the specific embodiments of this application or the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of this application. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0039] Figure 1 This is a schematic diagram of a quantum dot ink preparation method in one embodiment;

[0040] Figure 2 The fluorescence emission spectrum of the green quantum dot color conversion film prepared in Example 1;

[0041] Figure 3 The fluorescence emission spectrum of the red quantum dot color conversion film prepared in Example 2;

[0042] Figure 4 The fluorescence emission spectrum of the green quantum dot color conversion film prepared in Comparative Example 1 is shown.

[0043] Figure 5 The images shown are SEM images of the quantum dot color conversion films prepared in Examples 1 and 2 and Comparative Example 1. Detailed Implementation

[0044] To facilitate understanding of this application, a more complete description will be provided below with reference to the accompanying drawings. Preferred embodiments of this application are shown in the drawings. However, this application can be implemented in many different forms and is not limited to the embodiments described herein. Rather, these embodiments are provided to provide a thorough and complete understanding of the disclosure of this application.

[0045] 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 belongs. The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0046] Furthermore, the terms "first" and "second" are used for descriptive purposes only and should not be construed as indicating or implying relative importance or implicitly specifying the number of technical features indicated.

[0047] Currently available quantum dot inks for inkjet printing typically suffer from poor dispersion stability, unsatisfactory photocuring effects, high post-curing shrinkage, and low blue light absorption, all of which negatively impact the light extraction and conversion efficiency of the quantum dot color conversion film. Therefore, this application provides a quantum dot UV ink that addresses these issues. This quantum dot ink is suitable for both inkjet printing and photocuring, enabling instant drying.

[0048] In a first aspect, this application provides a quantum dot ink comprising the following components by mass percentage:

[0049] Quantum dots 10%–30%, epoxy resin 20%–50%, acrylic resin 10%–20%, scattering particles 5%–10%, active monomers 20%–30%, photoinitiator 0.1%–2%, and dispersant 0.1%–1%;

[0050] Photoinitiators include free radical photoinitiators and cationic photoinitiators;

[0051] The active monomer includes at least one of the acrylate compounds represented by Formula I:

[0052]

[0053] In Formula I, R1 is hydrogen or methyl, R2 is hydrogen, methyl or ethyl, and n is an integer from 1 to 4.

[0054] In the aforementioned quantum dot ink, scattering particles can alter the optical path of blue light, improving the utilization rate of blue light by quantum dots. Furthermore, scattering particles can reduce the transmittance of blue light, thereby improving the color purity of devices such as color conversion films and achieving higher external quantum efficiency. Moreover, the active monomer can undergo free radical photocuring reactions, and since it contains hydroxyl groups, it can undergo ring-opening polymerization with epoxy resin in cationic photocuring systems. Thus, under the action of a photoinitiator, the aforementioned quantum dot ink possesses both free radical and cationic photocuring characteristics. It has low curing energy, resulting in low volume shrinkage after curing, with the shrinkage rate after curing reaching below 2%. It also exhibits high blue light absorption values ​​(the absorption value of red quantum dot color conversion films can be increased to at least OD>2, and the absorption value of green quantum dot color conversion films can be increased to at least OD>1.8) and high external quantum efficiency (the external quantum efficiency (EQE) of red quantum dot color conversion films can reach over 35%, and the external quantum efficiency (EQE) of green quantum dot color conversion films can reach over 40%).

[0055] In some implementations, setting the mass percentage of quantum dots within the aforementioned range (10%–30%) ensures the content of effective luminescent material, provides the desired light color, and enhances the absorption of blue light, thereby increasing the OD value. Setting the mass percentage of scattering particles within the range of 5%–10% alters the blue light path, increasing the absorption of blue light by the quantum dots. Setting the mass percentage of active monomers within the range of 20%–30% adjusts the viscosity of the quantum dot ink to 5 cps–15 cps and the surface tension to 25 dyne / cm–35 dyne / cm to meet printing requirements.

[0056] In some embodiments, the quantum dots and scattering particles are chemically modified with the same organic ligand, which includes an active group for chemically modifying the quantum dots and scattering particles, the active group being selected from carboxyl, mercapto, zinc thiol, or amino groups.

[0057] It can be understood that chemical modification specifically refers to the formation of coordination links between quantum dots or scattering particles and the active groups of organic ligands. Modification of quantum dots with organic ligands can improve their dispersibility in active monomers, while modification of scattering particles with organic ligands can improve their dispersibility in acrylic resins. Furthermore, the identical organic ligands used to modify the quantum dots and scattering particles ensure that their surfaces carry the same charge, forming steric forces that hinder interparticle orientation (repulsion and steric hindrance). This further improves the dispersion stability of scattering particles and quantum dots in quantum dot inks, preventing aggregation and sedimentation, and preventing fluorescence loss during long-term storage. While ensuring printing stability, this significantly reduces storage costs, facilitating the long-term preservation and printing of large quantities of ink in industrial applications, and laying the foundation for obtaining quantum dot color conversion films with high quantum yields.

[0058] In this application, the quantum dot can be any quantum dot known in the art. In some embodiments, the quantum dot is a red quantum dot or a green quantum dot; wherein, the emission wavelength range of the red quantum dot is 600nm to 650nm, the half-width at half-maximum is <40nm, and the particle size is 6nm to 9nm; the emission wavelength range of the green quantum dot is 500nm to 550nm, the half-width at half-maximum is <30nm, and the particle size is 2nm to 5nm.

[0059] The elemental composition of quantum dots mainly originates from group I elements, such as one or more of II-VI, IV-VI, III-V, and I-VI. As an example, according to the material classification of quantum dots, they can specifically be selected from one or more of silicon quantum dots, germanium quantum dots, sulfide quantum dots, selenide quantum dots, telluride quantum dots, phosphide quantum dots, arsenide quantum dots, and copper indium sulfide quantum dots; among them, sulfide quantum dots include cadmium sulfide quantum dots and lead sulfide quantum dots, selenide quantum dots include cadmium selenide quantum dots, zinc selenide quantum dots, and lead selenide quantum dots, telluride quantum dots are cadmium telluride quantum dots, phosphide quantum dots include indium phosphide quantum dots and cadmium phosphide quantum dots, and arsenide quantum dots are indium arsenide quantum dots. According to the geometric shape of quantum dots, they can specifically be selected from cubic quantum dots, spherical quantum dots, tetrahedral quantum dots, cylindrical quantum dots, disk-shaped quantum dots, box-shaped quantum dots, and field-induced quantum dots. The structure of quantum dots includes those commonly used in the field of quantum dot inks, such as single-core structures, core-single-shell structures, core-multi-shell structures, and alloy structures.

[0060] In some implementations, the mass ratio of quantum dots to organic ligands is 1:(0.2 to 0.3).

[0061] In some embodiments, the epoxy resin has an epoxy equivalent of 150 g / Eg to 300 g / Eg and a number-average molecular weight of 5000 to 10000. By controlling the performance parameters of the epoxy resin within these ranges, the resulting quantum dot ink can possess viscosity and surface tension suitable for inkjet printing processes, ensuring smooth printing and preventing printhead clogging. Furthermore, it ensures stable dispersion of the quantum dot ink, preventing agglomeration and sedimentation, and preventing fluorescence loss during long-term storage.

[0062] In some embodiments, the epoxy resin includes one or more of alicyclic epoxy resins, phenolic epoxy resins, and glycidyl ether type epoxy resins. Phenolic epoxy resins are also known as type F epoxy resins; bisphenol F type epoxy resins are also known as bisphenol F diglycidyl ether, i.e., BPF resins; phenolic epoxy resins include linear phenolic epoxy resins (h type epoxy resins); glycidyl ether type epoxy resins refer to epoxy resins containing a glycidyl ether structure, such as bisphenol A type epoxy resins, bisphenol F type epoxy resins, bisphenol 5 type epoxy resins, and bisphenol AD ​​type epoxy resins. Specifically, alicyclic epoxy resins can be purchased from Daicel CELLOXIDE 2021P, CELLOXIDE 8000, CELLOXIDE 2081, GT401, Dow ERL4221, and Huntsman CY179 and CY184; phenolic epoxy resins can be purchased from Sanmu Chemical SMP101, SMP102, SMP103, SMP104, and SMP105; bisphenol A type epoxy resins can be purchased from Sanmu Chemical SM827, SM828, SM827H, and SM827L, and Nan Ya NPEL-128; and bisphenol F type epoxy resins can be purchased from Nan Ya NPEF-170, and Sanmu Chemical SMF-170 and SMF-175S.

[0063] In some embodiments, the acrylic resin has a viscosity of 1 cps to 5 cps and a number-average molecular weight ≤3000. The acrylic resin can disperse and wet the scattering particles, further ensuring stable dispersion and preventing sedimentation and aggregation. By controlling the performance parameters of the acrylic resin within the above range, the quantum dot ink can possess viscosity and surface tension suitable for inkjet printing, ensuring smooth printing and preventing ink clogging of the printhead. Furthermore, it ensures stable dispersion of the quantum dot ink, preventing aggregation and sedimentation, and preventing fluorescence loss during long-term storage.

[0064] In some embodiments, the scattering particles are nano-metal oxides, including one or more of TiO2, ZnO, SnO2, NiO, MoO, Al2O3, CeO2, and ZrO2.

[0065] In some implementations, the average particle size of the scattering particles is 50 nm to 100 nm. Controlling the average particle size within this range allows the scattering particles to possess advantages such as narrow particle size distribution, regular morphology, good dispersibility, and resistance to aggregation, thereby ensuring the dispersion stability of the quantum dot ink. Furthermore, if the average particle size of the scattering particles is less than 50 nm, it will result in excessively high blue light transmittance and excessively low absorption by the quantum dots; if the average particle size of the scattering particles is greater than 100 nm, it will produce a strong light-blocking effect, affecting the absorption of blue light by the quantum dots and reducing light extraction efficiency and light conversion efficiency.

[0066] In some embodiments, the mass ratio of the scattering particles to the organic ligands is 1:(0.2 to 0.3).

[0067] In some embodiments, in Formula I, R1 is hydrogen or methyl, R2 is hydrogen, methyl or ethyl, and n is 1; further, the active monomer includes, but is not limited to, one or more of hydroxyethyl methacrylate, hydroxypropyl methacrylate and hydroxybutyl methacrylate.

[0068] In this application, the organic ligands are primarily selected based on the presence of carboxyl, thiol, or amino active groups, and their ability to form coordination interactions with quantum dots or scattering particles. In some embodiments, the organic ligands are selected from oleylamine, oleic acid, zinc alkylthiolate, polythiol, or ammonium carboxylate.

[0069] In this application, the dispersant is primarily selected from modified polyurethane. This additive can deflocculate and stabilize quantum dots and scattering particles through steric hindrance, and can further impart the same charge to the quantum dots and scattering particles. The resulting repulsion effect and steric stabilization prevent co-flocculation of quantum dots and scattering particles, thereby further stabilizing the dispersion of the quantum dot ink. In some embodiments, the dispersant includes one or more of BYK163, BYK168, BYK180, BYK110, BYK108, and BYK103 dispersants.

[0070] In this application, the selection of radical photoinitiators and cationic photoinitiators is not limited; any photoinitiator commonly used in the art can be selected. In some embodiments, the radical photoinitiator is selected from one or more of azo, peroxide, and redox photoinitiators. Specifically, free radical photoinitiators include, but are not limited to, one or more of the following: benzoin isobutyl ether, benzoin ethyl ether, 2,4-diethyl acetophenone, 2-isopropyl acetophenone, 2,4,6-trimethylbenzoyl phosphate diethyl ester, 2,4,6-trimethylbenzoyl diphenylphosphine oxide, 6-trimethylbenzoyl diphenylphosphine oxide, 2-phenyl-2,2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, methyl o-benzoylbenzoate, phenyl bis(2,4,6-trimethylbenzoyl)phosphine oxide, bis(2,6-dimethoxybenzoyl)-(4,4-dimethyloctyl-2)phosphine oxide, 2,4-diethylthioxanthraquinone, 2-chlorothioxanthraquinone, and 2-ethylanthraquinone.

[0071] In some embodiments, the cationic photoinitiator is selected from one or more of iodonium salts, thiodonium salts, and iron aromatics. Specifically, the cationic photoinitiator includes, but is not limited to, one or more of diarylferric iodide salts, triaryl thiodonium salts and arylferrocene salts, thiodonium hexafluorophosphate salts, thiodonium hexafluoroantimonate salts, and mixed triarylhexafluoroantimonate thiodonium salts.

[0072] In some embodiments, the mass ratio of the radical photoinitiator to the cationic photoinitiator is 1:(1-2).

[0073] In some embodiments, the viscosity of the quantum dot ink is 5 cps to 15 cps, and the surface tension is 25 dyne / cm to 35 dyne / cm.

[0074] Secondly, this application provides a method for preparing the quantum dot ink described in the first aspect of this application, comprising the following steps:

[0075] Quantum dots, active monomers, and a first dispersant are mixed to form a first dispersion.

[0076] The scattering particles, acrylic resin, and second dispersant are mixed to form a second dispersion.

[0077] Epoxy resin and photoinitiator are mixed to form a third dispersion; and

[0078] Quantum dot ink is prepared by mixing a first dispersion, a second dispersion, and a third dispersion. The quantum dot ink comprises the following components in the indicated mass percentages: 10%–30% quantum dots, 20%–50% epoxy resin, 10%–20% acrylic resin, 5%–10% scattering particles, 20%–30% reactive monomers, 0.1%–2% photoinitiator, and a first and a second dispersant. The total mass percentage of the first and second dispersants is 0.1%–1% of the quantum dot ink. The photoinitiator includes both free radical and cationic photoinitiators.

[0079] The active monomer includes at least one of the acrylate compounds represented by Formula I:

[0080]

[0081] In Formula I, R1 is hydrogen or methyl, R2 is hydrogen, methyl or ethyl, and n is an integer from 1 to 4.

[0082] In some embodiments, the mass ratio of the first dispersant to the second dispersant is 1:(0.8 to 1.2).

[0083] The first dispersion and the second dispersion may be the same or different. Specific selection can be found in the first aspect of this application, and will not be repeated here.

[0084] In this application, the mixing method is not limited, as long as it can ensure that the components are evenly dispersed. In some embodiments, the mixing method is magnetic stirring or mixing using strong shear force.

[0085] Thirdly, this application provides a quantum dot color conversion film, which is formed by inkjet printing and curing using ink as the raw material, wherein the ink includes the quantum dot ink described above. The quantum dot color conversion film obtained by printing with the above ink has a high blue light absorption value and external quantum efficiency.

[0086] In some embodiments, the curing is performed by exposure to ultraviolet light with a wavelength of 300 nm to 400 nm, and the exposure energy is 280 mJ / cm². 2 ~350mJ / cm 2 .

[0087] Fourthly, this application provides an electroluminescent device comprising the quantum dot color conversion thin film described above.

[0088] In some implementations, the electroluminescent device is specifically an organic light-emitting diode (OLED), an organic light-emitting cell (OLEEC), an organic light-emitting field-effect transistor, a perovskite light-emitting diode (PeLED), or a quantum dot light-emitting diode (QD-LED).

[0089] Fifthly, this application provides a display device that includes the electroluminescent device described above.

[0090] In some implementations, the display device is specifically any product or component with display function, such as a mobile phone, tablet computer, television, monitor, laptop computer, or navigator, without being overly limited here.

[0091] The present application will be further described in detail below with reference to specific embodiments.

[0092] It should be noted that wt% represents the mass percentage.

[0093] In the following examples and comparative examples, the acrylic resin was purchased from Hypomer Company, brand name Hypomer PE9624;

[0094] The thionium hexafluorophosphate salt was purchased from Yuyang Technology Co., Ltd., and its grade is I-160.

[0095] The triarylhexafluoroantimony thioonium salt was purchased from Wengjiang Reagent Company, with the brand name PB97164.

[0096] The alicyclic epoxy resin was purchased from Dow Chemical Company, brand name ERL 4221, and the linear phenolic epoxy resin was purchased from Miki Chemical Company, brand name SMP 101.

[0097] Among them, the green quantum dots are cadmium selenide quantum dots, and the red quantum dots are cadmium sulfide quantum dots.

[0098] Example 1

[0099] The method for preparing quantum dot ink in this embodiment is as follows: Figure 1 As shown, the specific steps are as follows:

[0100] 1. Preparation of quantum dot UV ink

[0101] 1) 23 wt% green quantum dots with a particle size of 4.3 nm, 20 wt% hydroxyethyl methacrylate, and 0.4 wt% BYK163 dispersant were mixed and dispersed by magnetic stirring to obtain the first dispersion;

[0102] 2) 5 wt% TiO2 with an average particle size of 100 nm, 15 wt% acrylic resin, and 0.6 wt% BYK163 dispersant were mixed and dispersed by magnetic stirring to obtain a second dispersion.

[0103] Both green quantum dots and TiO2 were modified with organic ligands. The surface modification steps were as follows: oleic acid was added to the green quantum dot solution and the TiO2 solution, respectively. The mixture was magnetically stirred at 2500 rpm for 120 min at 70℃~80℃ to obtain carboxyl-modified green quantum dot solution and carboxyl-modified TiO2 solution, respectively. After centrifugation, the lower precipitate was dried at 80℃ to obtain carboxyl-modified green quantum dots and carboxyl-modified TiO2.

[0104] 3) 35wt% of an alicyclic epoxy resin with an epoxy equivalent of 150g / Eg to 170g / Eg and a number average molecular weight of 6000 to 8000 and 1wt% of a photoinitiator were mixed and dispersed by magnetic stirring to obtain a third dispersion; wherein the photoinitiator consisted of 0.4wt% of 2,4-diethylacetophenone and 0.6wt% of thiohexafluorophosphate salt;

[0105] 4) The first dispersion, the second dispersion and the third dispersion are mixed and dispersed by magnetic stirring to obtain green quantum dot UV ink.

[0106] 2. Preparation of color conversion thin films

[0107] The green quantum dot UV ink obtained in step 1 was printed into the pixel pits using inkjet printing technology. The ink was then exposed to a 365nm ultraviolet light source with an exposure energy of 300mJ / cm². 2 A green quantum dot color conversion film with a thickness of 8.6 μm was obtained. The fluorescence emission spectrum of this green quantum dot color conversion film is as follows: Figure 2 As shown.

[0108] Example 2

[0109] 1. Preparation of quantum dot UV ink

[0110] 1) 20 wt% red quantum dots with a particle size of 7 nm, 20 wt% hydroxypropyl methacrylate, and 0.5 wt% BYK180 dispersant were mixed and dispersed by magnetic stirring to obtain the first dispersion.

[0111] 2) 7 wt% ZnO with an average particle size of 70 nm, 17 wt% acrylic resin, and 0.5 wt% BYK180 dispersant were mixed and dispersed by magnetic stirring to obtain a second dispersion.

[0112] Both red quantum dots and ZnO were modified with organic ligands. The surface modification steps were as follows: polythiol was added to the red quantum dot solution and the ZnO solution respectively. The mixture was magnetically stirred at 2500 rpm for 120 min at 70℃~80℃ to obtain thiol-modified red quantum dot solution and thiol-modified ZnO solution respectively. After centrifugation, the lower precipitate was dried at 80℃ to obtain thiol-modified green quantum dots and thiol-modified ZnO.

[0113] 3) 34 wt% of linear phenolic epoxy resin with an epoxy equivalent of 180 g / Eg to 200 g / Eg and a molecular weight of 7500 to 9000 and 1 wt% of photoinitiator were mixed and dispersed by magnetic stirring to obtain a third dispersion; wherein the photoinitiator consisted of 0.5 wt% of diethyl 2,4,6-trimethylbenzoyl phosphate and 0.5 wt% of triarylhexafluoroantimony thionium salt;

[0114] 4) The first dispersion, the second dispersion and the third dispersion are mixed and dispersed by magnetic stirring to obtain red quantum dot UV ink.

[0115] 2. Preparation of color conversion thin films

[0116] The red quantum dot UV ink prepared in step 1 was printed into the pixel pits using inkjet printing technology. The ink was then exposed to a 365nm ultraviolet light source at an exposure energy of 300mJ / cm². 2 A red quantum dot color conversion film with a thickness of 8.9 μm was obtained. The fluorescence emission spectrum of this red quantum dot color conversion film is as follows: Figure 3 As shown.

[0117] Example 3

[0118] 1. Preparation of quantum dot UV ink

[0119] 1) 12 wt% green quantum dots with a particle size of 5.1 nm, 20 wt% hydroxyethyl methacrylate, and 0.3 wt% BYK110 dispersant were mixed and dispersed by magnetic stirring to obtain the first dispersion;

[0120] 2) 6 wt% SnO2 with an average particle size of 110 nm, 20 wt% acrylic resin, and 0.7 wt% BYK110 dispersant were mixed and dispersed by magnetic stirring to obtain a second dispersion.

[0121] Both green quantum dots and SnO2 were modified with organic ligands. The surface modification steps were as follows: ammonium carboxylate was added to the green quantum dot solution and SnO2 solution respectively, and the mixture was magnetically stirred at 2500 rpm for 120 min at 70℃~80℃ to obtain carboxyl-modified green quantum dot solution and carboxyl-modified SnO2 solution respectively. After centrifugation, the lower precipitate was dried at 80℃ to obtain carboxyl-modified green quantum dots and carboxyl-modified SnO2.

[0122] 3) 39.5 wt% of an alicyclic epoxy resin with an epoxy equivalent of 150 g / Eg to 170 g / Eg and a molecular weight of 6000 to 8000 and 1.5 wt% of a photoinitiator were mixed and dispersed by magnetic stirring to obtain a third dispersion; wherein the photoinitiator consisted of 0.6 wt% of 2,4-diethylthioxanthrone and 0.9 wt% of thioonium hexafluorophosphate.

[0123] 4) The first dispersion, the second dispersion and the third dispersion are mixed and dispersed by magnetic stirring to obtain green quantum dot UV ink.

[0124] 2. Preparation of color conversion thin films

[0125] The green quantum dot UV ink obtained in step 1 was printed into the pixel pits using inkjet printing technology. The ink was then exposed to a 365nm ultraviolet light source at an exposure energy of 350mJ / cm². 2 A green quantum dot color conversion film with a thickness of 8.8 μm was obtained.

[0126] Example 4

[0127] 1. Preparation of quantum dot UV ink

[0128] 1) 28 wt% red quantum dots with a particle size of 8.1 nm, 20 wt% hydroxybutyl methacrylate, and 0.5 wt% BYK103 dispersant were mixed and dispersed by magnetic stirring to obtain the first dispersion;

[0129] 2) 5 wt% NiO with an average particle size of 66 nm, 15 wt% acrylic resin and 0.5 wt% BYK103 dispersant were mixed and dispersed by magnetic stirring to obtain a second dispersion.

[0130] Both red quantum dots and NiO were modified with organic ligands. The surface modification steps were as follows: alkyl thiol zinc was added to the red quantum dot solution and NiO solution respectively, and the mixture was magnetically stirred at 2500 rpm for 120 min at 70℃~80℃ to obtain zinc thiol modified red quantum dot solution and zinc thiol modified NiO solution respectively. After centrifugation, the lower precipitate was dried at 80℃ to obtain zinc thiol modified red quantum dots and zinc thiol modified NiO.

[0131] 3) 30 wt% of linear phenolic epoxy resin with an epoxy equivalent of 180 g / Eg to 200 g / Eg and a molecular weight of 7500 to 9000 and 1 wt% of photoinitiator were mixed and dispersed by magnetic stirring to obtain a third dispersion; wherein the photoinitiator consisted of 0.5 wt% of methyl o-benzoylbenzoate and 0.5 wt% of triarylhexafluoroantimony thioonium salt;

[0132] 4) The first dispersion, the second dispersion and the third dispersion are mixed and dispersed by magnetic stirring to obtain red quantum dot UV ink.

[0133] 2. Preparation of color conversion thin films

[0134] The red quantum dot UV ink prepared in step 1 was printed into the pixel pits using inkjet printing technology. The ink was then exposed to a 365nm ultraviolet light source at an exposure energy of 330mJ / cm². 2 A red quantum dot color conversion film with a thickness of 8.5 μm was obtained.

[0135] Example 5

[0136] The preparation method in this embodiment is basically the same as that in Example 1, except for the average particle size of the scattering particles. The specific steps are as follows:

[0137] 1. Preparation of quantum dot UV ink

[0138] 1) 23 wt% green quantum dots with a particle size of 4.3 nm, 20 wt% hydroxyethyl methacrylate, and 0.4 wt% BYK163 dispersant were mixed and dispersed by magnetic stirring to obtain the first dispersion;

[0139] 2) 5 wt% TiO2 with an average particle size of 140 nm, 15 wt% acrylic resin, and 0.6 wt% BYK163 dispersant were mixed and dispersed by magnetic stirring to obtain a second dispersion.

[0140] Both green quantum dots and TiO2 were modified with organic ligands. The surface modification steps were as follows: oleic acid was added to the green quantum dot solution and the TiO2 solution, respectively. The mixture was magnetically stirred at 2500 rpm for 120 min at 70℃~80℃ to obtain carboxyl-modified green quantum dot solution and carboxyl-modified TiO2 solution, respectively. After centrifugation, the lower precipitate was dried at 80℃ to obtain carboxyl-modified green quantum dots and carboxyl-modified TiO2.

[0141] 3) 35wt% of an alicyclic epoxy resin with an epoxy equivalent of 150g / Eg to 170g / Eg and a molecular weight of 6000 to 8000 and 1wt% of a photoinitiator were mixed and dispersed by magnetic stirring to obtain a third dispersion; wherein the photoinitiator consisted of 0.4wt% of 2,4-diethylacetophenone and 0.6wt% of thiohexafluorophosphate salt;

[0142] 4) The first dispersion, the second dispersion and the third dispersion are mixed and dispersed by magnetic stirring to obtain green quantum dot UV ink.

[0143] 2. Preparation of color conversion thin films

[0144] The green quantum dot UV ink obtained in step 1 was printed into the pixel pits using inkjet printing technology. The ink was then exposed to a 365nm ultraviolet light source with an exposure energy of 300mJ / cm². 2 A green quantum dot color conversion film with a thickness of 8.6 μm was obtained.

[0145] Example 6

[0146] The preparation method in this embodiment is basically the same as that in Example 2, except for the average particle size and type of the scattering particles. The specific steps are as follows:

[0147] 1. Preparation of quantum dot UV ink

[0148] 1) 20 wt% red quantum dots with a particle size of 7.9 nm, 20 wt% hydroxypropyl methacrylate, and 0.5 wt% BYK180 dispersant were mixed and dispersed by magnetic stirring to obtain the first dispersion;

[0149] 2) 7 wt% CeO2 with an average particle size of 50 nm, 17 wt% acrylic resin and 0.5 wt% BYK180 dispersant were mixed and dispersed by magnetic stirring to obtain a second dispersion.

[0150] Both red quantum dots and ZnO were modified with organic ligands. The surface modification steps were as follows: polythiol was added to the red quantum dot solution and the ZnO solution respectively. The mixture was magnetically stirred at 2500 rpm for 120 min at 70℃~80℃ to obtain thiol-modified red quantum dot solution and thiol-modified ZnO solution respectively. After centrifugation, the lower precipitate was dried at 80℃ to obtain thiol-modified green quantum dots and thiol-modified ZnO.

[0151] 3) 34 wt% of linear phenolic epoxy resin with an epoxy equivalent of 180-200 g / Eg and a molecular weight of 7500-9000 and 1 wt% of photoinitiator were mixed and dispersed by magnetic stirring to obtain a third dispersion; wherein the photoinitiator consisted of 0.5 wt% of diethyl 2,4,6-trimethylbenzoyl phosphate and 0.5 wt% of triarylhexafluoroantimony thionium salt;

[0152] 4) The first dispersion, the second dispersion and the third dispersion are mixed and dispersed by magnetic stirring to obtain red quantum dot UV ink.

[0153] 2. Preparation of color conversion thin films

[0154] The red quantum dot UV ink prepared in step 1 was printed into the pixel pits using inkjet printing technology. The ink was then exposed to a 365nm ultraviolet light source with an exposure energy of 340mJ / cm². 2 A red quantum dot color conversion film with a thickness of 8.6 μm was obtained.

[0155] This application utilizes hydroxyl-containing acrylate monomers as active monomers, enabling simultaneous free radical photocuring and cationic photocuring. In the cationic photocuring system, hydroxyl groups act as chain transfer agents during photopolymerization, accelerating the polymerization process. The photocuring rate, curing shrinkage, and film-forming properties of this type of monomer in the mixed photocuring system are superior to those in the single curing system. Combining the two photocuring systems creates a uniform and dense three-dimensional network structure, thereby improving the curing effect of the color conversion film.

[0156] Example 7

[0157] The preparation method of Example 7 is basically the same as that of Example 1, except that the quantum dots and scattering particles are not modified with ligands. The specific steps are as follows:

[0158] 1. Preparation of quantum dot UV ink

[0159] 1) 23 wt% green quantum dots with a particle size of 4.3 nm, 20 wt% hydroxyethyl methacrylate, and 0.4 wt% BYK163 dispersant were mixed and dispersed by magnetic stirring to obtain the first dispersion;

[0160] 2) 5 wt% TiO2 with an average particle size of 100 nm, 15 wt% acrylic resin, and 0.6 wt% BYK163 dispersant were mixed and dispersed by magnetic stirring to obtain a second dispersion.

[0161] 3) 35wt% of an alicyclic epoxy resin with an epoxy equivalent of 150-170 g / Eg and a molecular weight of 6000-8000 and 1wt% of a photoinitiator were mixed and dispersed by magnetic stirring to obtain a third dispersion; wherein the photoinitiator consisted of 0.4wt% of 2,4-diethylacetophenone and 0.6wt% of thiohexafluorophosphate.

[0162] 4) The first dispersion, the second dispersion and the third dispersion are mixed and dispersed by magnetic stirring to obtain green quantum dot UV ink.

[0163] 2. Preparation of color conversion thin films

[0164] The green quantum dot UV ink obtained in step 1 was printed into the pixel pits using inkjet printing technology. The ink was then exposed to a 365nm ultraviolet light source with an exposure energy of 300mJ / cm². 2 A green quantum dot color conversion film with a thickness of 8.7 μm was obtained.

[0165] Example 8

[0166] The preparation method of Example 8 is basically the same as that of Example 1, except that the quantum dots are modified with zinc-based thiol and the scattering particles are modified with carboxyl groups. The specific steps are as follows:

[0167] 1. Preparation of quantum dot ink

[0168] 1) 23 wt% green quantum dots with a particle size of 4.3 nm, 20 wt% hydroxyethyl methacrylate, and 0.4 wt% BYK163 dispersant were mixed and dispersed by magnetic stirring to obtain the first dispersion;

[0169] 2) 5 wt% TiO2 with an average particle size of 100 nm, 15 wt% acrylic resin, and 0.6 wt% BYK163 dispersant were mixed and dispersed by magnetic stirring to obtain a second dispersion.

[0170] The green quantum dots and scattering particles were modified with organic ligands. The surface modification steps for the green quantum dots were as follows: alkyl thiol zinc was added to the green quantum dot solution, and the mixture was magnetically stirred at 2500 rpm for 120 min at 70℃~80℃ to obtain a zinc thiol-modified red quantum dot solution. After centrifugation, the lower precipitate was dried at 80℃ to obtain zinc thiol-modified green quantum dots. The surface modification steps for the scattering particles were as follows: oleic acid was added to the TiO2 solution, and the mixture was magnetically stirred at 2500 rpm for 120 min at 70℃~80℃ to obtain a carboxyl-modified TiO2 solution. After centrifugation, the lower precipitate was dried at 80℃ to obtain carboxyl-modified TiO2.

[0171] 3) 35wt% of an alicyclic epoxy resin with an epoxy equivalent of 150-170 g / Eg and a molecular weight of 6000-8000 and 1wt% of a photoinitiator were mixed and dispersed by magnetic stirring to obtain a third dispersion; wherein the photoinitiator consisted of 0.4wt% of 2,4-diethylacetophenone and 0.6wt% of thiohexafluorophosphate.

[0172] 4) The first dispersion, the second dispersion and the third dispersion are mixed and dispersed by magnetic stirring to obtain green quantum dot UV ink.

[0173] 2. Preparation of color conversion thin films

[0174] The green quantum dot UV ink obtained in step 1 was printed into the pixel pits using inkjet printing technology. The ink was then exposed to a 365nm ultraviolet light source with an exposure energy of 300mJ / cm². 2 A green quantum dot color conversion film with a thickness of 8.9 μm was obtained.

[0175] Comparative Example 1

[0176] In this comparative example, the quantum dot UV ink is cured using free radical photocuring. The specific steps are as follows:

[0177] 1. Preparation of quantum dot UV ink

[0178] Green quantum dot UV ink was obtained by magnetically stirring and dispersing 23 wt% green quantum dots, 20 wt% isobornyl methacrylate, 51 wt% acrylic resin, 5 wt% TiO2, and 1 wt% 2,4,6-trimethylbenzoyl diphenylphosphine oxide. Both the green quantum dots and TiO2 were modified with oleic acid ligands. The surface modification steps were as follows: oleic acid was added to the green quantum dot solution and the TiO2 solution, respectively, and the mixture was magnetically stirred at 2500 rpm for 120 min at 70℃~80℃ to obtain green quantum dot solution and TiO2 solution with oleic acid ligands, respectively. After centrifugation, the lower precipitate was dried at 80℃ to obtain green quantum dots and TiO2 with oleic acid ligands.

[0179] 2. Preparation of color conversion thin films

[0180] The green quantum dot UV ink prepared in step 1 was printed into the pixel pits using inkjet printing, and exposed to a 365nm ultraviolet light source with an exposure energy of 400mJ / cm². 2 A green quantum dot color conversion film with a thickness of 7.7 μm was obtained. The fluorescence emission spectrum of this green quantum dot color conversion film is as follows: Figure 4 As shown.

[0181] The dispersibility tests of the quantum dot UV inks prepared in each embodiment and comparative example are shown in Table 1.

[0182] Table 1

[0183]

[0184]

[0185] The test results above show that the quantum dot UV ink provided in this application has excellent dispersion performance and excellent printing effect. After continuous printing for 5 hours, the printhead is not clogged and the ink droplet trajectory is not deviated. After being stored at room temperature (25°C) in the dark for 2 months, it can still print smoothly for at least 5 hours. Compared with Comparative Example 1, Example 1 uses a dual-curing system formed by free radical and cationic photocuring, which can improve the dispersion stability of quantum dot UV ink. Compared with Example 7, Example 1 uses surface modification of quantum dots and scattering particles, which can ensure better dispersibility and stability in quantum dot UV ink, enabling stable printing for a long time. The cured color conversion film has a higher OD value and EQE. Compared with Example 8, the quantum dots and scattering particles in Example 1 undergo the same surface modification treatment and have the same surface ligands, which can ensure that their surfaces carry the same charge. This can form a steric hindrance effect between particles and a steric hindrance effect, thereby further improving the dispersion stability of scattering particles and quantum dots in quantum dot ink. There will be no aggregation or sedimentation. After being stored at room temperature (25°C) in the dark for 2 months, it can still print smoothly for 5 hours.

[0186] SEM images of the color conversion films prepared in Examples 1 and 2 and Comparative Example 1 after curing are shown below. Figure 5 As shown. By Figure 5 It can be seen that the quantum dot color conversion film prepared in Comparative Example 1 exhibits numerous shrinkage points and poor printability, with a volume shrinkage exceeding 10% calculated using the hydrometer bottle method. In contrast, the quantum dot color conversion films prepared in Examples 1 and 2 are printed uniformly without shrinkage, with a volume shrinkage of less than 2% calculated using the hydrometer bottle method. Based on printing the same volume of ink, after curing, the film thickness of Example 1 is 8.6 μm, the film thickness of Example 2 is 8.9 μm, and the film thickness of Comparative Example 1 is only 7.7 μm. This demonstrates that the quantum dot ink provided in this application exhibits no shrinkage during curing, and the ink does not form depressions in the bank, thus improving the light extraction efficiency of the quantum dot color conversion film, preventing light leakage, and ensuring uniform color.

[0187] The quantum dot color conversion films prepared in Examples 1-8 and Comparative Example 1 were tested for optical properties. The test results are shown in Table 2 below.

[0188] The test conditions for each performance test item are as follows:

[0189] 1) The absorption of 450nm blue light by the quantum dot color conversion film was tested using an ultraviolet spectrophotometer;

[0190] 2) The wavelength, full width at half maximum (FWHM), and external quantum efficiency of quantum dot color conversion films were tested using the integrating sphere method.

[0191] Table 2

[0192]

[0193] As shown in Table 2 above, with the same thickness of quantum dot color conversion film, the quantum dot color conversion films prepared in Examples 1-6 have better OD and EQE. For the green quantum dot color conversion film, the OD and EQE of Example 1 are far superior to those of Examples 7 and 8 and Comparative Example 1; among them, the external quantum efficiency (EQE) of the red quantum dot color conversion film can reach 35%, and the external quantum efficiency (EQE) of the green quantum dot color conversion film can reach 40%, that is, the light extraction efficiency and light conversion efficiency of the quantum dot color conversion film are relatively high.

[0194] Therefore, it can be seen that the quantum dot ink provided in this application can achieve an OD greater than 2 (i.e., blue light absorption rate > 99%) when the thickness of the quantum dot color conversion film is less than 10μm, which can ensure a high color gamut and color purity, thereby ensuring the realization of high-quality images.

[0195] The technical features of the above embodiments can be combined in any way. For the sake of brevity, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0196] The embodiments described above are merely illustrative of several implementation methods of this application, and while the descriptions are relatively specific and detailed, they should not be construed as limiting the scope of the invention patent. It should be noted that those skilled in the art can make various modifications and improvements without departing from the concept of this application, and these all fall within the protection scope of this application. Therefore, the protection scope of this patent application should be determined by the appended claims, and the specification and drawings can be used to interpret the scope of the claims.

Claims

1. A quantum dot ink, characterized in that, It contains the following components by mass percentage: Quantum dots 10%~30%, epoxy resin 20%~50%, acrylic resin 10%~20%, scattering particles 5%~10%, active monomers 20%~30%, photoinitiator 0.1%~2%, and dispersant 0.1%~1%; The photoinitiator includes a free radical photoinitiator and a cationic photoinitiator, and the mass ratio of the free radical photoinitiator to the cationic photoinitiator is 1:(1~2). The active monomer includes at least one of the acrylate compounds represented by Formula I: Formula I, In Formula I, R1 is hydrogen or methyl, R2 is hydrogen, methyl or ethyl, and n is an integer from 1 to 4; The curing volume shrinkage rate of the quantum dot ink is ≤2%; The quantum dots include one or more of silicon quantum dots, germanium quantum dots, sulfide quantum dots, selenide quantum dots, telluride quantum dots, phosphide quantum dots, arsenide quantum dots, and copper indium sulfide quantum dots; The scattering particles are nano-metal oxides, including one or more of TiO2, ZnO, SnO2, NiO, MoO, Al2O3, CeO2 and ZrO2; The quantum dots and the scattering particles are chemically modified with the same organic ligand, which includes an active group for chemically modifying the quantum dots and the scattering particles, the active group being selected from carboxyl, mercapto, zinc thiol or amino groups.

2. The quantum dot ink as described in claim 1, characterized in that, The mass ratio of the scattering particles to the organic ligand is 1:(0.2~0.3).

3. The quantum dot ink as described in claim 1, characterized in that, The average particle size of the scattering particles is 50 nm to 100 nm.

4. The quantum dot ink as described in claim 1, characterized in that, The epoxy resin has an epoxy equivalent of 150 g / Eq to 300 g / Eq and a number average molecular weight of 5000 to 10000.

5. The quantum dot ink as described in claim 4, characterized in that, The epoxy resin includes one or more of alicyclic epoxy resins, phenolic epoxy resins, and glycidyl ether type epoxy resins.

6. The quantum dot ink according to any one of claims 1 to 5, characterized in that, The quantum dot ink has at least one of the following characteristics: 1) In formula I, R1 is hydrogen or methyl, R2 is hydrogen, methyl or ethyl, and n is 1; 2) The organic ligand is selected from oleylamine, oleic acid, zinc alkylthiolate, polythiol or ammonium carboxylate; 3) The dispersant includes one or more of BYK163 dispersant, BYK168 dispersant, BYK180 dispersant, BYK110 dispersant, BYK108 dispersant and BYK103 dispersant; 4) The mass ratio of the quantum dot to the organic ligand is 1:(0.2~0.3).

7. The quantum dot ink according to claim 6, characterized in that, The active monomer includes one or more of hydroxyethyl methacrylate, hydroxypropyl methacrylate, and hydroxybutyl methacrylate.

8. The quantum dot ink according to any one of claims 1 to 5, characterized in that, The acrylic resin has a viscosity of 1 cps to 5 cps and a number-average molecular weight of ≤3000.

9. The quantum dot ink according to any one of claims 1 to 5, characterized in that, The photoinitiator has at least one of the following characteristics: 1) The free radical photoinitiator includes one or more of the following: benzoin isobutyl ether, benzoin ethyl ether, 2,4-diethyl acetophenone, 2-isopropyl acetophenone, 2,4,6-trimethylbenzoyl phosphate diethyl ester, 2,4,6-trimethylbenzoyl diphenylphosphine oxide, 6-trimethylbenzoyl diphenylphosphine oxide, 2-phenyl-2,2-dimethylamino-1-(4-morpholinophenyl)-1-butanone, methyl o-benzoylbenzoate, phenyl bis(2,4,6-trimethylbenzoyl)phosphine oxide, bis(2,6-dimethoxybenzoyl)-(4,4-dimethyloctyl-2)phosphine oxide, 2,4-diethylthioxanthraquinone, 2-chlorothioxanthraquinone, and 2-ethylanthraquinone; 2) The cationic photoinitiator includes one or more of the following: diaryliodomonium salt, triarylthiomonium salt, arylferrocene salt, hexafluorophosphate thiomonium salt, hexafluoroantimony thiomonium salt, and mixed triarylhexafluoroantimony thiomonium salt.

10. A method for preparing quantum dot ink, characterized in that, Includes the following steps: Quantum dots, active monomers, and a first dispersant are mixed to form a first dispersion. The scattering particles, acrylic resin, and second dispersant are mixed to form a second dispersion. Epoxy resin and photoinitiator are mixed to form a third dispersion; and Quantum dot ink is prepared by mixing a first dispersion, a second dispersion, and a third dispersion; wherein the quantum dot ink comprises the following components in the following mass percentages: quantum dots 10%~30%, epoxy resin 20%~50%, acrylic resin 10%~20%, scattering particles 5%~10%, active monomers 20%~30%, photoinitiator 0.1%~2%, a first dispersant, and a second dispersant; the total amount of the first dispersant and the second dispersant accounts for 0.1%~1% of the mass percentage of the quantum dot ink; the photoinitiator includes a free radical photoinitiator and a cationic photoinitiator, and the mass ratio of the free radical photoinitiator to the cationic photoinitiator is 1:(1~2). The active monomer includes at least one of the acrylate compounds represented by Formula I: Equation I, In Formula I, R1 is hydrogen or methyl, R2 is hydrogen, methyl or ethyl, and n is an integer from 1 to 4; The curing volume shrinkage rate of the quantum dot ink is ≤2%; The quantum dots include one or more of silicon quantum dots, germanium quantum dots, sulfide quantum dots, selenide quantum dots, telluride quantum dots, phosphide quantum dots, arsenide quantum dots, and copper indium sulfide quantum dots; The scattering particles are nano-metal oxides, including one or more of TiO2, ZnO, SnO2, NiO, MoO, Al2O3, CeO2 and ZrO2; The quantum dots and the scattering particles are chemically modified with the same organic ligand, which includes an active group for chemically modifying the quantum dots and the scattering particles, the active group being selected from carboxyl, mercapto, zinc thiol or amino groups.

11. A quantum dot color conversion thin film, characterized in that, It is made by inkjet printing and curing using ink as raw material, wherein the ink includes the quantum dot ink as described in any one of claims 1 to 9.

12. An electroluminescent device, characterized in that, Includes the quantum dot color conversion film as described in claim 11.

13. A display device, characterized in that, Including the electroluminescent device as described in claim 12.

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