Quantum dot printing ink, preparation method thereof and display device

Abstract

This application provides a quantum dot printing ink, its preparation method, and a display device, relating to the field of display technology. The raw material components of the quantum dot printing ink include: 10wt%-40wt% quantum dot material, 1wt%-5wt% modified hexagonal boron nitride, 20wt%-40wt% organic monomer, and 20wt%-40wt% acrylic resin. The preparation method includes: mixing the quantum dot material and modified hexagonal boron nitride separately with the organic monomer to obtain a quantum dot monomer dispersion and a modified hexagonal boron nitride monomer dispersion; adding the mixed solution of the two dispersions to the acrylic resin and dispersing evenly to obtain the quantum dot printing ink. The quantum dot printing ink of this application can reduce the fluorescence quenching phenomenon of quantum dot material caused by excessive heat accumulation during printing, reduce the possibility of nozzle clogging during printing, improve ink flow smoothness, and increase the utilization rate of printing consumables.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of display, in particular to a quantum dot printing ink, a preparation method thereof and a display device. BACKGROUND

[0002] With the deep pursuit of human beings for display technology, display technology gradually develops in the direction of small size and high resolution. Micro LED is a representative of micro display technology, which is generally defined as an LED display chip with a size of less than 50pm. The pixel array composed of it lays the foundation for future XR display technology. One of the technical routes for Micro LED to realize full-color display is to use color conversion microarrays prepared by color conversion materials and related micro-nano processing technology to convert the blue light emitted by themselves into red and green light. Among them, quantum dot (quantum dot, QD for short) material is a commonly used color conversion material, which has superior photoluminescence performance such as wide absorption, narrow emission, high color purity, high quantum yield, and adjustable emission wavelength; Electro-hydrodynamic (electro-hydrodynamic, EHD for short) jet printing technology can realize extremely high-resolution pixel printing and can be applied to the preparation of super-small size and high-resolution Micro LED color conversion layer.

[0003] The principle of EHD jet printing technology is to form an electric field force between the substrate and the nozzle during the printing process by high-voltage electricity to pull out the printing ink from the nozzle to form a jet. Obviously, in the whole printing process, the QD material will be in the electric field formed by high-voltage electricity for a long time. This is easy to cause various irreversible deteriorations of QD materials, such as material breakdown by high-voltage electricity; the strong polarization effect of high-voltage electric field acting on QD causes the surface ligand to fall off and form agglomeration; the free radicals generated by the excitation of part of the components in the ink by high-voltage electricity will also deteriorate the performance of QD; the QD ink is a hot poor conductor, and the QD ink is excited by high-voltage electricity for a long time, and the heat accumulation generated by the thermal quenching of QD cannot be ignored. Therefore, under the combined influence of the above factors, the QD ink in the EHD jet printing technology often shows a phenomenon that the luminescence performance of QD materials is seriously weakened on a macroscopic scale, and problems such as nozzle blockage, uneven ink discharge, and inability to continuously jet print occur during the printing process. SUMMARY

[0004] In order to solve the above problems, the purpose of the present application is to provide a quantum dot printing ink, a preparation method thereof and a display device, which can solve the problems of incoherent ink discharge, nozzle blockage and performance failure of QD materials after printing process by strengthening the heat conduction and insulation performance of the ink.

[0005] In order to achieve the above purpose, the technical scheme of the present application is as follows:

[0006] In a first aspect, the application provides a quantum dot printing ink, raw material components of which include: 10wt%-40wt% quantum dot material, 1wt%-5wt% modified hexagonal boron nitride, 20wt%-40wt% organic monomer and 20wt%-40wt% acrylic resin.

[0007] Preferably, the quantum dot material satisfies at least one of the following conditions:

[0008] a. The quantum dot material includes any one of II-VI group quantum dots, III-V group quantum dots and perovskite quantum dots;

[0009] b. The particle size of the quantum dot material is 5nm-20nm;

[0010] c. The quantum dot material emits visible light in the wavelength range of 500nm-700nm under blue light irradiation of 450nm-460nm.

[0011] Preferably, the modified hexagonal boron nitride satisfies at least one of the following conditions:

[0012] d. The modified hexagonal boron nitride includes hexagonal boron nitride modified by surface hydroxyl and esterification;

[0013] e. The hexagonal boron nitride includes at least one of zero-dimensional quantum dot structure, two-dimensional nanosheet structure and three-dimensional nanotubular structure;

[0014] f. The particle size of the hexagonal boron nitride is 2nm-500nm.

[0015] Preferably, at least one of the following conditions is also satisfied:

[0016] g. The organic monomer includes acrylic monomer;

[0017] h. The acrylic resin includes reaction crosslinking type acrylic resin;

[0018] i. The raw material components of the quantum dot printing ink further include optical additives;

[0019] j. The mass of the optical additives is 0%-5% of the total mass of the quantum dot printing ink;

[0020] k. The optical additives include at least one of titanium dioxide, zinc oxide, tin oxide, zirconium dioxide, calcium carbonate and barium sulfate;

[0021] l. The particle size of the optical additives is 50nm-500nm.

[0022] Preferably, the quantum dot printing ink is used for electrofluid inkjet printing.

[0023] In a second aspect, the application further provides a preparation method of the quantum dot printing ink of the first aspect, comprising:

[0024] mixing the quantum dot material and the modified hexagonal boron nitride independently with the organic monomer to obtain a quantum dot monomer dispersion and a modified hexagonal boron nitride monomer dispersion, respectively;

[0025] adding the quantum dot monomer dispersion and the modified hexagonal boron nitride monomer dispersion into the acrylic resin, and uniformly dispersing to obtain the quantum dot printing ink.

[0026] Preferably, the preparation method of the modified hexagonal boron nitride comprises:

[0027] surface hydroxyl modification of hexagonal boron nitride with an alkaline compound to obtain hydroxylated hexagonal boron nitride, and then reacting with an unsaturated acid anhydride to obtain the modified hexagonal boron nitride.

[0028] Preferably, when the raw material components of the quantum dot printing ink further comprise an optical additive, the preparation method further comprises:

[0029] adding the optical additive to the acrylic resin before the uniform dispersion.

[0030] Preferably, before obtaining the quantum dot monomer dispersion, the modified hexagonal boron nitride monomer dispersion, and the quantum dot printing ink, a vacuum defoaming treatment is further performed.

[0031] In a third aspect, the application further provides a display device comprising a color conversion layer, which is prepared by printing the quantum dot printing ink of the first aspect.

[0032] The application has the following beneficial effects:

[0033] The quantum dot printing ink of the application adds modified hexagonal boron nitride to the ink raw materials, which greatly improves the heat transfer performance and insulation performance of the quantum dot printing ink due to the high thermal conductivity and excellent electrical insulation performance of the modified hexagonal boron nitride. In the printing process, the heat generated by the long-time high-voltage electric excitation of the ink can be promptly dissipated, reducing the excessive heat-induced fluorescence quenching of the quantum dot material in the ink, improving the reliability of the quantum dot printing ink, and reducing the possibility of ligand drop caused by the strong polarization of the quantum dot material under the high-voltage electric field, the possibility of material breakdown under high-voltage electric field, and the possibility of nozzle blockage in the printing process, improving the smoothness of ink ejection, and further improving the utilization rate of printing consumables.

[0034] The preparation method of the quantum dot printing ink is simple in process, ensures uniform dispersion of raw materials, and enables the prepared ink to be less prone to sedimentation and the like, and can be prepared in large scale. BRIEF DESCRIPTION OF DRAWINGS

[0035] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the following will briefly introduce the drawings needed to be used in the embodiments. It should be understood that the following drawings only show some embodiments of the present application, and therefore should not be regarded as a limitation on the scope of the present application.

[0036] Figure 1 Microscope photo of the tip of the printing needle after printing the ink of Example 1;

[0037] Figure 2 Microscope photo of the tip of the printing needle after printing the ink of Comparative Example 1. DETAILED DESCRIPTION

[0038] As used herein the terms “about” and “substantially” mean approximately or nearly, as in “about 90%” or “substantially parallel.” These terms of approximation can allow for a degree of variance understood by one of ordinary skill in the art.

[0039] “Made from” is synonymous with “comprising.” The terms “comprising,” “including,” “containing,” “having” or any other similar forms are intended to be open-ended inclusive terms. For example, a composition, a step, a method, an article, or an apparatus that comprises a list of elements is not necessarily limited to only those elements but can include other elements not expressly listed, or inherent to such composition, step, method, article, or apparatus.

[0040] The conjunctive term “consisting of’ excludes any element, step, or ingredient not specified. If used in the claims, this phrase shall not be construed to mean that the noted elements or steps are essential to the practice of the claims. The phrase “consisting of’ does not foreclose the addition of additional steps, materials, or components, nor does it exclude components that are not named. When the phrase “consisting of’ follows the introductory material of a claim, it indicates that the scope of the claim is limited to the listed elements, but does not exclude additional elements that are not named.

[0041] When numerical ranges are disclosed, the endpoints of the ranges are included. Unless otherwise indicated, the range is inclusive of the recited endpoints. When the use of “about” is so indicated, the application includes the exact amounts. For example, the range “about 1 to 5” is intended to include “about 1 to about 5,” “about 1 to 5,” “about 1 to about 5,” “about 1 to about 5,” etc. When numerical ranges are disclosed, unless otherwise stated, the range is intended to include all integers and fractions within the range. For example, the range “1 to 5” is intended to include “1, 2, 3, 4, and 5,” as well as fractions of these values, such as, for example, 1.1, 1.2, 1.3, 1.4, 1.5, etc.

[0042] In these embodiments, unless otherwise specified, the portions and percentages are all by weight.

[0043] "Parts by mass" refers to the basic unit of measurement that expresses the mass ratio of multiple components. One part can represent any unit mass, such as 1g or 2.689g. If we say that component A has "a" parts by mass and component B has "b" parts by mass, it means the ratio of the mass of component A to the mass of component B is a:b. Alternatively, it can mean that the mass of component A is aK and the mass of component B is bK (K is any number representing a multiplier). It is important to understand that, unlike the number of parts by mass, the sum of the mass parts of all components is not limited to 100 parts.

[0044] "And / or" is used to indicate that one or both of the described situations may occur, for example, A and / or B includes (A and B) and (A or B).

[0045] In a first aspect, this application provides a quantum dot printing ink, the raw material components of which include: 10wt%-40wt% quantum dot material, 1wt%-5wt% modified hexagonal boron nitride, 20wt%-40wt% organic monomer and 20wt%-40wt% acrylic resin.

[0046] In conjunction with the first aspect, in one feasible implementation, the quantum dot material includes any one of group II-VI quantum dots, group III-V quantum dots, and perovskite quantum dots. The quantum dot material can be a quantum dot that emits red light or a quantum dot that emits green light.

[0047] It should be noted that this application does not specifically limit the structure of quantum dot materials. They can be mononuclear structures, core-shell structures, etc., and further, they can be core-monolayer shell structures or core-multilayer shell structures.

[0048] In one feasible implementation, the particle size of the quantum dot material is 5nm-20nm, for example, it can be 5nm, 8nm, 10nm, 12nm, 15nm, 18nm, 20nm or any value between 5nm and 20nm.

[0049] In one feasible implementation, the quantum dot material emits visible light in the wavelength range of 500nm-700nm when irradiated with blue light at 450nm-460nm.

[0050] In one feasible embodiment, the modified hexagonal boron nitride includes hexagonal boron nitride that has undergone surface hydroxyl modification and esterification modification.

[0051] In one feasible implementation, the hexagonal boron nitride comprises at least one of a zero-dimensional quantum dot structure, a two-dimensional nanosheet structure, and a three-dimensional nanotube structure.

[0052] In one feasible implementation, the particle size of the hexagonal boron nitride is 2nm-500nm, for example, it can be 2nm, 50nm, 100nm, 150nm, 200nm, 300nm, 400nm, 500nm or any value between 2nm and 500nm.

[0053] It should be noted that adding hexagonal boron nitride to ink raw materials can improve the thermal conductivity and insulation properties of the ink. However, most insulating / thermal conductive materials are only in bulk form and cannot meet the requirements of micro-nano sizes, making them difficult to use as raw materials in inks for printing. Hexagonal boron nitride, on the other hand, can be matched with the processing scenarios of different types of micro-nano materials. Furthermore, after surface modification treatment, modified cubic boron nitride can be easily dispersed in organic monomer solvents. In contrast, other dense insulating materials such as alumina are difficult to surface modify, making it difficult to disperse uniformly in solvents. Or, although many insulating materials can be modified, the modification is difficult and far less convenient than the modification conditions of hexagonal boron nitride.

[0054] In one feasible embodiment, the organic monomer includes acrylic monomers. Specifically, the acrylic monomers may be acrylic acid, methyl acrylate, ethyl acrylate, butyl acrylate, isobutyl acrylate, hexyl acrylate, isooctyl acrylate, lauryl acrylate, benzyl acrylate, cyclohexyl acrylate, perfluoroalkyl acrylate, hydroxyethyl phosphate acrylate, isobornyl acrylate, tetrahydrofuran methyl acrylate, methacrylic acid, methyl methacrylate, ethyl methacrylate, butyl methacrylate, isobutyl methacrylate, hexyl methacrylate, methyl...

[0055] At least one of lauryl acrylate, isobornyl methacrylate, and cyclohexyl methacrylate. In one feasible embodiment, the acrylic resin comprises a reactive crosslinking acrylic resin.

[0056] It should be noted that the quantum dot printing ink used in this application uses reactive cross-linking acrylic resin primarily so that, under light irradiation, the propylene in the reactive cross-linking acrylic resin...

[0057] The acid resin undergoes internal cross-linking and solidification due to the action of the photoinitiator, fixing the quantum dot material in the formed ink film layer and ensuring the stability of the color conversion layer obtained by printing.

[0058] In one feasible implementation, the raw material components of the quantum dot ink also include optical additives. The mass of the optical additives does not exceed 5% of the total mass of the quantum dot printing ink, for example, it can be 0.1%, 0.5%, 1%, 2%, 3%, 4%, 5%, or any value between 0% and 5%.

[0059] Further preferably, the optical additive includes at least one selected from titanium dioxide, zinc oxide, tin oxide, and zirconium dioxide, and the particle size of the optical additive is 50nm-500nm, for example, it can be 50nm, 100nm, 200nm, 300nm, 400nm, 500nm, or any value between 50nm and 500nm. More preferably, the optical additive is titanium dioxide.

[0060] These optical additives are essentially photocatalytic materials that can promote chemical reactions of other substances without undergoing any changes themselves under light.

[0061] Secondly, this application also provides a method for preparing the aforementioned quantum dot printing ink, including:

[0062] S1. The quantum dot material and the modified hexagonal boron nitride are each independently mixed with the organic monomer to obtain quantum dot monomer dispersion and modified hexagonal boron nitride monomer dispersion, respectively.

[0063] S2. Add the quantum dot monomer dispersion and the modified hexagonal boron nitride monomer dispersion to the acrylic resin and disperse them evenly to obtain the quantum dot printing ink.

[0064] Specifically, during mixing in S1, thorough stirring can be performed first, followed by ultrasonic oscillation to ensure a homogeneous distribution of the mixed solution, especially to ensure that the quantum dot material and modified hexagonal boron nitride can be stably suspended in their respective monomer dispersions.

[0065] In one feasible embodiment, the method for preparing the modified hexagonal boron nitride in S1 includes: mixing hexagonal boron nitride with an alkaline compound to perform surface hydroxylation modification to obtain hydroxylated hexagonal boron nitride, and then mixing the hydroxylated hexagonal boron nitride with an unsaturated acid anhydride to react and obtain modified hexagonal boron nitride.

[0066] Furthermore, the alkaline compound includes at least one of sodium hydroxide and potassium hydroxide, and the unsaturated anhydride includes at least one of maleic anhydride and itaconic anhydride.

[0067] In one feasible implementation, when the raw materials of the quantum dot printing ink also include optical additives, the preparation method of the quantum dot printing ink further includes: adding optical additives to the acrylic resin in S2, and then dispersing them evenly. Specifically, the preparation method in S1 remains unchanged, but in S2, the quantum dot monomer dispersion, the modified hexagonal boron nitride monomer dispersion, the optical additives, and the acrylic resin need to be mixed and then dispersed evenly to obtain the quantum dot printing ink.

[0068] In one feasible implementation, after mixing in S1 and after uniform dispersion in S2, each step independently includes: performing vacuum degassing treatment.

[0069] Understandably, ink that has undergone vacuum degassing will flow more smoothly during subsequent printing, and the printed ink layer will be free of air bubbles.

[0070] Thirdly, this application also provides a display device including a color conversion layer, specifically a Micro LED color conversion layer for ultra-small size and high resolution, wherein the color conversion layer is prepared by printing with the aforementioned quantum dot printing ink.

[0071] The embodiments of the present invention will be described in detail below with reference to specific examples. However, those skilled in the art will understand that the following examples are for illustrative purposes only and should not be considered as limiting the scope of the invention. Unless otherwise specified in the examples, conventional conditions or conditions recommended by the manufacturer are followed. Reagents or instruments whose manufacturers are not specified are all commercially available products.

[0072] Example 1

[0073] The quantum dot printing ink of this embodiment is specifically prepared by the following method:

[0074] (1) Preparation of quantum dot (RQD) monomer dispersion: Weigh 3g of red quantum dot (RQD) material. Group II-VI red quantum dot material can be selected. Its microscopic particle size is 12nm. When irradiated with 450nm blue light, the RQD material can emit 622nm red visible light. Weigh 1.5g of methyl acrylate. Mix the two together, stir thoroughly, sonicate, and after complete dissolution, perform vacuum degassing to obtain the RQD monomer dispersion for later use.

[0075] (2) Preparation of hexagonal boron nitride (h-BN) monomer dispersion: Weigh 0.25g of modified hexagonal boron nitride (h-BN) material. The microstructure of this h-BN material is a single-layer lamellar structure. The h-BN material is subjected to surface hydroxylation modification treatment with strong NaOH base, followed by surface esterification modification with maleic anhydride to enable it to have good compatibility with acrylic monomers and resins. Weigh 1.5g of methyl acrylate and mix it with the above modified hexagonal boron nitride. Stir thoroughly, sonicate, and after complete dissolution, perform vacuum degassing to obtain the h-BN monomer dispersion for later use.

[0076] (3) Quantum dot printing ink preparation: Weigh 2g of reactive acrylic resin and 0.1g of TiO2, mix them with the RQD monomer dispersion and h-BN monomer dispersion prepared in steps (1) and (2), stir thoroughly, so that the above components are evenly dispersed by ultrasound, and then perform vacuum degassing to obtain a homogeneous quantum dot printing ink.

[0077] Example 2

[0078] The quantum dot printing ink of this embodiment is specifically prepared by the following method:

[0079] (1) Preparation of quantum dot (PQD) monomer dispersion: Weigh 3g of green perovskite quantum dot (PQD) material with a microscopic particle size of 8nm. When irradiated with 450nm blue light, the PQD material can emit 515nm green visible light. Weigh 1.5g of methyl acrylate, mix the two together, stir thoroughly, sonicate, and after complete dissolution, perform vacuum degassing to obtain the PQD monomer dispersion for later use.

[0080] (2) Preparation of hexagonal boron nitride (h-BN) monomer dispersion: Weigh 0.25g of modified hexagonal boron nitride (h-BN) material. The microstructure of this h-BN material is a single-layer lamellar structure. The h-BN material is subjected to surface hydroxylation modification treatment with strong NaOH base, followed by surface esterification modification with maleic anhydride to enable it to have good compatibility with acrylic monomers and resins. Weigh 1.5g of isobutyl methacrylate and mix it with the above modified hexagonal boron nitride. Stir thoroughly, sonicate, and after complete dissolution, perform vacuum degassing to obtain the h-BN monomer dispersion for later use.

[0081] (3) Quantum dot printing ink preparation: Weigh 2g of reactive acrylic resin and mix it with the PQD monomer dispersion and h-BN monomer dispersion prepared in steps (1) and (2). Stir thoroughly, sonicate to make the above components uniformly dispersed, and then perform vacuum degassing to obtain a homogeneous quantum dot printing ink.

[0082] Example 3

[0083] Similar to Example 1, except that: in step (1), 3g of green II-VI group quantum dot (GQD) material was weighed, with a micro-particle size of 10nm. When irradiated with 450nm blue light, the GQD material can emit 535nm green visible light; in step (2), the microstructure of the h-BN material is a three-dimensional nanotube structure; and 1.5g of isobornyl methacrylate was weighed.

[0084] Example 4

[0085] The quantum dot printing ink of this embodiment is specifically prepared by the following method:

[0086] (1) Preparation of quantum dot (QD) monomer dispersion: Weigh 3g of green quantum dot (GQD) material and 0.8g of red quantum dot (RQD) material, both of which belong to group II-VI quantum dots. Their micro-particle size is G: 10nm and R: 12nm. Under 450nm blue light irradiation, GQD and RQD materials can emit green / red visible light of 535nm and 622nm respectively. Weigh 1.5g of isobornyl acrylate and mix them. Stir thoroughly and sonicate. After complete dissolution, vacuum degassing is performed to obtain QD monomer dispersion for later use. Its appearance is yellow-green.

[0087] (2) Preparation of hexagonal boron nitride (h-BN) monomer dispersion: Weigh 0.25g of modified hexagonal boron nitride (h-BN) material. The microstructure of this h-BN material is a single-layer lamellar structure. The h-BN material is subjected to surface hydroxylation modification treatment with strong NaOH base, followed by surface esterification modification with maleic anhydride to enable it to have good compatibility with acrylic monomers and resins. Weigh 1.5g of isobornyl acrylate and mix it with the above-mentioned modified hexagonal boron nitride. Stir thoroughly, sonicate, and after complete dissolution, perform vacuum degassing to obtain the h-BN monomer dispersion for later use.

[0088] (3) Quantum dot printing ink preparation: Weigh 2g of reactive acrylic resin and 0.1g of TiO2, mix them with the QD monomer dispersion and h-BN monomer dispersion prepared in steps (1) and (2), stir thoroughly, so that the above components are evenly dispersed by ultrasonication, and then perform vacuum degassing to obtain a homogeneous quantum dot printing ink.

[0089] The quantum dot color conversion layer prepared using this ink, when combined with a Micro LED chip array, can realize the fabrication of a Micro LED white light panel.

[0090] Comparative Example 1

[0091] The quantum dot printing ink used in this comparative example is prepared using the following specific methods:

[0092] (1) Preparation of quantum dot (RQD) monomer dispersion: Weigh 3g of red quantum dot (RQD) material. Group II-VI red quantum dot material can be selected. Its micro-particle size is 12nm. When irradiated with 450nm blue light, the RQD material can emit 622nm red visible light. Weigh 3g of methyl acrylate, mix the two together, stir thoroughly, sonicate, and after complete dissolution, perform vacuum degassing to obtain RQD monomer dispersion for later use.

[0093] (2) Quantum dot printing ink preparation: Weigh 2g of reactive acrylic resin and 0.1g of TiO2, mix with the RQD monomer dispersion prepared in step (1), stir thoroughly, so that the above components are evenly dispersed by ultrasound, and then perform vacuum degassing to obtain a homogeneous quantum dot printing ink.

[0094] Printing tests were conducted on the inks prepared in Examples 1-4 and Comparative Example 1, respectively. The tests were performed on the same printer with the same printing parameters.

[0095] The settings for the EHD printing equipment include:

[0096] Voltage parameters:

[0097] (1) Waveform: Square wave

[0098] (2) V1 voltage: 0.6kV

[0099] (3) V2 voltage: -0.6kV

[0100] (4) Pulse width: 10ms

[0101] In addition, the thermal conductivity of the printed color conversion layer was tested using an HS-DR-5 transient planar thermal conductivity meter.

[0102] Table 1 lists the quantum dot inks prepared in Example 1 and Comparative Example 1, as well as the experimental results after printing tests.

[0103] Table 1

[0104]

[0105] Figure 1 The image provided shows a photograph of the inkjet nozzle tip under a 6X microscope after printing with the ink prepared in Example 1. Figure 2 The images show photographs of the inkjet nozzle tip after printing with the ink prepared in Comparative Example 1, taken under a microscope at the same magnification. It is clear from the images that the nozzle tip of Example 1 is free of blockages, while the nozzle tip of Comparative Example 1 is blocked.

[0106] Combined with the data in Table 1, it is shown that the quantum dot printing ink of this application significantly reduces the possibility of nozzle clogging during printing and improves the smoothness of ink output after printing with electrohydrodynamic printing equipment. Moreover, after the quantum dot material undergoes the printing process, the color conversion layer emits higher brightness after being excited by blue light, thus solving the problem of quantum dot performance failure after printing.

[0107] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, and not to limit them; although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art should understand that modifications can still be made to the technical solutions described in the foregoing embodiments, or equivalent substitutions can be made to some or all of the technical features; and these modifications or substitutions do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

[0108] Furthermore, those skilled in the art will understand that although some embodiments herein include certain features included in other embodiments but not others, combinations of features from different embodiments are meant to be within the scope of the invention and form different embodiments. For example, in the foregoing claims, any of the claimed embodiments can be used in any combination. The information disclosed in this background section is intended only to enhance the understanding of the general background of the invention and should not be construed as an admission or in any way implying that such information constitutes prior art known to those skilled in the art.

Claims

1. A quantum dot printing ink, characterized in that, The raw material components of the quantum dot printing ink include: 10wt%-40wt% quantum dot material, 1wt%-5wt% modified hexagonal boron nitride, 20wt%-40wt% organic monomer and 20wt%-40wt% acrylic resin; The particle size of the quantum dot material is 5nm-20nm; The quantum dot material emits visible light in the range of 500nm-700nm when irradiated with blue light at 450nm-460nm. The modified hexagonal boron nitride includes hexagonal boron nitride that has undergone surface hydroxyl modification and esterification modification; The hexagonal boron nitride includes at least one of a zero-dimensional quantum dot structure, a two-dimensional nanosheet structure, and a three-dimensional nanotube structure. The particle size of the hexagonal boron nitride is 2nm-500nm; The organic monomers include acrylic monomers; The acrylic resin includes a reactive crosslinking acrylic resin.

2. The quantum dot printing ink as described in claim 1, characterized in that, The quantum dot material includes any one of group II-VI quantum dots, group III-V quantum dots, and perovskite quantum dots.

3. The quantum dot printing ink as described in claim 1, characterized in that, At least one of the following conditions must be met: i. The raw material components of the quantum dot printing ink also include optical additives; j. The mass of the optical additive is 0-5% of the total mass of the quantum dot printing ink; k. The optical additive includes at least one of titanium dioxide, zinc oxide, tin oxide, zirconium dioxide, calcium carbonate, and barium sulfate; l. The particle size of the optical additive is 50nm-500nm.

4. The quantum dot printing ink according to any one of claims 1-3, characterized in that, The quantum dot printing ink is used for electrofluid inkjet printing.

5. A method for preparing quantum dot printing ink as described in any one of claims 1-4, characterized in that, include: The quantum dot material and the modified hexagonal boron nitride are each independently mixed with the organic monomer to obtain quantum dot monomer dispersion and modified hexagonal boron nitride monomer dispersion, respectively. The quantum dot monomer dispersion and the modified hexagonal boron nitride monomer dispersion are added to the acrylic resin and dispersed evenly to obtain the quantum dot printing ink.

6. The preparation method according to claim 5, characterized in that, The method for preparing the modified hexagonal boron nitride includes: Hexagonal boron nitride is surface-hydroxylated with an alkaline compound to obtain hydroxylated hexagonal boron nitride, which is then reacted with an unsaturated acid anhydride to obtain the modified hexagonal boron nitride.

7. The preparation method according to claim 5, characterized in that, When the raw material components of the quantum dot printing ink further include optical additives, the preparation method further includes: Before the dispersion is uniform, the optical additive is added to the acrylic resin.

8. The preparation method according to any one of claims 5-7, characterized in that, Before obtaining the quantum dot monomer dispersion, the modified hexagonal boron nitride monomer dispersion, and the quantum dot printing ink, the process further includes: performing vacuum degassing treatment.

9. A display device, characterized in that, The display device includes a color conversion layer, which is prepared by printing with the quantum dot printing ink according to any one of claims 1-4.

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