Multi-functional modified quantum dot composite adhesive material and graphical preparation method thereof

Abstract

The invention provides a multi-functional modified quantum dot composite adhesive material and a graphical preparation method thereof, and the quantum dot composite adhesive material comprises quantum dots, a resin system and a multifunctional ligand, the multifunctional ligand comprises a first ligand, a second ligand and a third ligand; the first ligand contains a long-chain alkyl group, a polar solvent nucleophilic group or a polar solvent nucleophilic group externally connected with the long-chain alkyl group; in the curing process, the first active functional group of the second ligand and / or the second active functional group of the third ligand and a resin monomer are selectively subjected to addition, condensation, copolymerization or ring-opening specific reaction for covalent bonding, so that covalent connection with a resin cross-linked network is constructed on the surface of the quantum dot, and covalent anchoring and embedding of the quantum dot are realized; the reaction mode is dynamically adapted according to the resin system. The problems that in the prior art, QDs are poor in dispersity and insufficient in stability in a resin / glue system, and bonding between the QDs and resin monomers in the resin system is not firm can be solved.

Description

Technical Field

[0001] This invention relates to the field of quantum dot technology and composite materials, and in particular to a multifunctional modified quantum dot composite adhesive material and its patterning preparation method, which can be applied to display devices, optical devices and photolithography preparation. Background Technology

[0002] Quantum dots (QDs) are widely used in display, lighting and photolithography fields due to their excellent properties such as narrow half-width, high brightness and tunable emission wavelength. However, the application of QDs in polymer matrix or photoresist system still faces the following challenges: (1) Insufficient dispersibility: The surface of quantum dots is generally coated with long-chain organic ligands (such as oleic acid), which are prone to agglomeration in polar or highly cross-linked resin matrix, resulting in optical performance degradation; (2) Lack of cross-linking ability: The ligands on the surface of conventional QDs are mostly hydrophobic alkyl groups, which cannot participate in the subsequent photo / thermal curing reaction and only exist in the polymer network in the form of physical filling, resulting in phase separation or migration under long-term thermal and photo-aging; (3) Insufficient compatibility with host resin: Even if ligands with polymeric functional groups (such as acrylic acid and epoxy groups) are introduced, quantum dots mostly participate in cross-linking in a non-selective manner and cannot achieve strong interaction with specific resin monomers, so the stability is still insufficient. Summary of the Invention

[0003] To address the aforementioned technical problems, this invention provides a multifunctional modified quantum dot composite adhesive material and its patterning preparation method, thereby solving the problems of poor dispersibility, insufficient stability, and weak bonding between QDs and resin monomers in the resin system in the prior art.

[0004] To achieve the above objectives, the present invention provides a multifunctional modified quantum dot composite adhesive material, the quantum dot composite adhesive material comprising quantum dots, a resin system, and multifunctional ligands, wherein the resin system comprises resin monomers, and the multifunctional ligands comprise: A first ligand, comprising a long-chain alkyl group, a polar solvent nucleophilic group, or a polar solvent nucleophilic group externally attached with a long-chain alkyl group, is used to promote the uniform dispersion of the quantum dots in the resin system. A second ligand, the second ligand containing a first active functional group, is adapted to the resin system; A third ligand, wherein the third ligand contains a second active functional group and is compatible with the resin system; During the curing process of the quantum dot composite adhesive, the first active functional group carried by the second ligand and / or the second active functional group carried by the third ligand selectively undergo addition, condensation, copolymerization or ring-opening specific reactions with the resin monomer or resin system to form covalent bonds, which are used to build covalent connections between the quantum dot surface and the resin crosslinking network, thereby realizing the covalent anchoring and embedding of the quantum dots. The reaction mode is dynamically adapted according to the resin system.

[0005] As an optional technical solution, the first ligand is selected from one or more of hexadecylphosphonic acid, phosphonic acid-polyethylene glycol segments, carboxyl-dodecane chains, and sulfonic acid derivatives.

[0006] As an optional technical solution, when the resin monomer is a phenolic resin monomer, the first active functional group includes a hydroxymethyl functional group, and the second active functional group includes a phenolic hydroxyl or aldehyde functional group; under the triggering of a catalyst or heating, the hydroxymethyl group can undergo etherification or dehydration condensation with the active site (ortho or para) of the aromatic ring of the phenolic resin monomer or the third ligand to form an ether bond or a methylene bridge, thereby fixing the quantum dots and embedding them into the phenolic resin crosslinking network through the above covalent bonds; When the resin monomer is an acrylic / methacrylic acid resin monomer, the first active functional group includes an acrylic or methacrylate functional group that can participate in addition polymerization, and the second active functional group includes a methacrylate functional group, an allyl functional group, or other copolymerizable unsaturated olefin functional groups. In the presence of photoinitiator, thermal initiator, or free radical initiator, the second ligand, the third ligand, and the acrylic / methacrylic acid resin monomer form a covalent backbone or cross-linked structure through free radical polymerization / copolymerization reaction, thereby covalently embedding and anchoring the quantum dots in the acrylic / methacrylic acid resin cross-linked network in a copolymerization manner. When the resin monomer is an epoxy resin monomer, the first active functional group includes an epoxy functional group, and the second active functional group includes an amino or carboxyl functional group; under catalytic or heating conditions, the amino or carboxyl functional group undergoes ring-opening addition with the epoxy functional group in a nucleophilic manner to form β-hydroxyamine bonds or β-hydroxy ester bonds, respectively, thereby covalently fixing the quantum dots in the epoxy resin crosslinking network by forming addition products; When the resin system is a polyamide resin system containing an amide structure or a resin system involving isocyanate reaction, the first active functional group includes an isocyanate functional group, and the second active functional group includes a hydroxyl functional group or an amino functional group; the isocyanate functional group reacts with the hydroxyl functional group to form a urethane bond, or reacts with the amino functional group to form a urea bond, thereby anchoring the quantum dots in the resin crosslinking network through covalent bonds.

[0007] As an optional technical solution, the third ligand is a silane hydrolysis product, and the general formula of the silane hydrolysis product is Y(CH2). n Si(OH)3, where n is a natural number greater than or equal to 1; Y is a non-hydrolyzable organic functional group that can undergo specific reactions with the resin monomer; the Si(OH)3 functional group in the silane hydrolysis product is retained for binding and protecting the quantum dot material; the resin monomer has an unsaturated functional group with an unsaturation degree of 1, which can undergo an addition reaction with the non-hydrolyzable organic functional group in the silane hydrolysis product to introduce silanol groups onto the resin monomer, while retaining the silanol groups for subsequent quantum dot binding and stabilization protection; The first active functional group of the second ligand is selected from one or more of acrylate, epoxy, vinyl, and isocyanate groups; The resin system includes the silane hydrolysis product, the resin monomer, the first solvent, and the surfactant.

[0008] As an optional technical solution, the unsaturated functional groups of the resin monomer are selected from one or more of carbon-carbon double bonds, carbon-nitrogen double bonds, carbon-oxygen double bonds, and epoxy alkyl groups.

[0009] As an optional technical solution, the resin monomer is selected from one or a mixture of two or more of acrylic resin monomers, epoxy resin monomers, phenolic resin monomers, and polyamide resin monomers.

[0010] As an optional technical solution, the silane hydrolysis product is prepared by hydrolyzing a silane coupling agent under preset temperature and pH conditions, wherein the general formula of the silane coupling agent is Y(CH2). n SiX3, where X is a hydrolytic functional group.

[0011] As an optional technical solution, the silane coupling agent is selected from one or a mixture of two or more of γ-methacryloxypropyltrimethoxysilane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, and glycidyl etheroxypropyltrimethoxysilane.

[0012] As an optional technical solution, the surface of the quantum dot has an initial ligand, which is selected from one or more of the following categories: (A) Straight-chain saturated fatty acids with a carbon chain length of C14~C18; (B) Straight-chain monounsaturated fatty acids with a carbon chain length of C14~C18 and containing one cis double bond; (C) Low molecular weight fatty amines, including tributylamine, tri-n-octylamine and C12~C18 straight-chain primary amines; (D) Straight-chain or branched oleamide derivatives containing amino or alkyl-substituted amine groups, used for quantum dot surface stabilization; The initial ligand forms a coordination bond with the surface of the quantum dot and can be partially replaced or covalently anchored with the second and third ligands.

[0013] As an optional technical solution, the quantum dots are selected from one or a mixture of several of CdSe, CdS, ZnS, CdZnSe, CdZnS, CdZnSeS, ZnSeS, ZnSe, CuInS, CuInSe, InP, and InZnP.

[0014] As an optional technical solution, the curing method of the curing process includes ultraviolet light curing, thermal curing, or catalyst curing.

[0015] As an optional technical solution, the mass ratio of the quantum dot, the first ligand, the second ligand, and the third ligand is (1–20): (0.5–5): (0.5–5): (0.1–3).

[0016] This invention also provides a patterning preparation method for the multifunctional modified quantum dot composite adhesive material as described above, the patterning preparation method comprising the following steps: Step S1, preparation of multi-ligand modified quantum dots: add quantum dots, first ligand, second ligand and third ligand to 50~200mL of second solvent, stir at room temperature for 2~4h, then heat to 45~60℃ and react for 4~10h, centrifuge at 6000~8000rpm and wash 2~3 times to obtain multi-ligand modified quantum dots; Step S2, preparation of composite adhesive: The obtained multi-ligand modified quantum dots are dispersed in the resin system, sonicated for 5-15 min and stirred for 20-30 min to form a uniform composite adhesive; and the mass percentage of the multi-ligand modified quantum dots is 0.1-10 wt%, based on the mass of the composite adhesive. Step S3, film formation and curing: Spin-coating the composite adhesive onto the substrate, the wet film thickness is 10~50μm; curing is carried out according to the resin system using the curing method to obtain the cross-linked cured film layer; Step S4, Photolithography Patterning: Expose using a photolithography mask, develop to remove uncrosslinked areas, and form a patterned quantum dot composite film layer.

[0017] The present invention also provides a quantum dot light-emitting device, the quantum dot light-emitting device comprising a substrate and a quantum dot composite adhesive film layer disposed in cooperation with the substrate, the substrate comprising light-emitting units arranged in an array, the quantum dot composite adhesive film layer being formed on the substrate such that the light-emitting surface of the light-emitting unit is covered by the quantum dot composite adhesive film layer, characterized in that the quantum dot composite adhesive film layer is formed by a patterning preparation method of a multifunctional modified quantum dot composite adhesive material as described above.

[0018] The present invention also provides a display device, the display device comprising the quantum dot light-emitting device as described above.

[0019] Compared with existing technologies, this invention enhances the stability of quantum dots from multiple dimensions through the synergistic effect of a first ligand, a second ligand, and a third ligand: The first ligand provides hydrophobic / resinophilic interface regulation, ensuring uniform dispersion of quantum dots in solvents and resin systems, laying the foundation for subsequent modification; the first active functional group carried by the second ligand and / or the second active functional group carried by the third ligand selectively undergo addition, condensation, copolymerization, or ring-opening specific reactions with the resin monomer or resin system to form covalent bonds, constructing covalent connections between the quantum dot surface and the resin crosslinking network, thereby achieving covalent anchoring and embedding of the quantum dot resin crosslinking network.

[0020] Moreover, through customized ligand strategies, it can be adapted to different resin systems (acrylic, epoxy, phenolic, polyamide, etc.), ensuring that quantum dots still have high fluorescence efficiency and long lifetime in complex environments. At the same time, since the quantum dots are uniformly distributed in the network and are spatially confined, photo-induced / thermal quenching can be effectively reduced, and the uniformity of light emission and pattern clarity can be improved.

[0021] In quantum dot light-emitting devices (QLEDs), triligand-modified quantum dots can be uniformly dispersed in a resin matrix to form a stable covalent network, enabling the device to maintain high luminous efficiency and long lifetime under continuous driving or high-temperature operating conditions. In sensor or optical detection applications, triligand-modified quantum dots, due to their network embedding and interface stability, can maintain fluorescence stability in complex solution environments, improving detection accuracy and reliability. Attached Figure Description

[0022] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in 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 the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0023] Figure 1 This is a schematic flowchart of a patterned preparation method for a multifunctional modified quantum dot composite adhesive material according to an embodiment of the present invention. Figure 2 This is a schematic diagram of the blue light aging test of the patterned quantum dot composite adhesive film layer prepared in Examples 1-4 and Comparative Example 1 of the present invention. Figure 3 This is a schematic diagram of the photolithographic patterning effect of the patterned quantum dot composite adhesive film layer prepared in Examples 1-4 and Comparative Example 1 of the present invention. Detailed Implementation

[0024] To provide a further understanding of the purpose, structure, features, and functions of the present invention, detailed descriptions are provided below with reference to specific embodiments.

[0025] The first aspect of this invention provides a multifunctional modified quantum dot composite adhesive material, comprising quantum dots, a resin system (or adhesive system), and a multifunctional ligand. The resin system comprises a resin monomer, and the multifunctional ligand comprises a first ligand, a second ligand, and a third ligand. The first ligand contains a long-chain alkyl group or a polar solvent nucleophilic group, or the first ligand contains a polar solvent nucleophilic group externally attached to a long-chain alkyl group, for promoting uniform dispersion of the quantum dots in the resin system. The second ligand contains a first active functional group adapted to the resin system. Specifically, the first active functional group is selected from one or more of acrylate, hydroxymethyl, methacrylate, epoxy, vinyl, and isocyanate functional groups. The third ligand contains a second active functional group adapted to the resin system. During the curing process of the quantum dot composite adhesive, the first active functional group carried by the second ligand and / or the second active functional group carried by the third ligand selectively undergo addition, condensation, copolymerization, or ring-opening specific reactions with the resin monomer or resin system to form covalent bonds. This is used to construct covalent connections between the quantum dots and the resin crosslinking network on the quantum dot surface, achieving covalent anchoring and embedding of the quantum dots. The reaction mode dynamically adapts according to the type of resin monomer, ensuring the stability of the binding between the quantum dots and the resin crosslinking network under different resin systems.

[0026] In other words, the core function of the first ligand in this invention is to improve the dispersibility of quantum dots in solvents (such as PGMEA, N-methylpyrrolidone, butyl acetate, etc.) and / or resin systems, inhibiting aggregation and sedimentation at the source and laying the foundation for subsequent crosslinking and anchoring. Specifically, the long-chain alkyl or polar solvent nucleophilic groups introduced by the first ligand, or polar solvent nucleophilic groups externally attached to long-chain alkyl groups, can tightly bind to the surface of the quantum dots, forming a stable protective layer. This protective layer not only increases the interaction force between the quantum dots and surrounding solvent molecules but also effectively prevents the quantum dots from approaching each other through steric hindrance, thereby avoiding aggregation and sedimentation. Furthermore, in polar solvents such as PGMEA (propylene glycol methyl ether acetate), butyl acetate, and NMP (N-methylpyrrolidone), the polar solvent nucleophilic groups of the first ligand (e.g., polyethylene glycol (PEG), sulfonic acid groups, etc.) can form hydrogen bonds or dipole interactions with solvent molecules, enabling the quantum dots to be uniformly dispersed in the solvent, improving the compatibility of the quantum dots with the system, and avoiding phase separation due to polarity differences. The aforementioned polar solvent nucleophilic groups are, for example, strongly polar groups such as carboxyl groups (-COOH), sulfonic acid groups (-SO3H), and phosphonic acid groups (-PO3H2). The polarity and length of the long-chain alkyl segments can be flexibly adjusted according to the target solvent and resin system to achieve "precise matching." The first ligand is, for example, selected from one or more of hexadecylphosphonic acid, phosphonic acid-polyethylene glycol segments, carboxyl-dodecane chains, and sulfonic acid derivatives.

[0027] During the dispersion stage, the metal atoms (such as Cd and Zn) on the quantum dot surface contain empty orbitals. The first, second, and third ligands provide lone pairs of electrons through coordinating groups such as carboxyl and amino groups, forming stable coordination bonds with the metal atoms and competitively replacing the original weakly bound ligands on the quantum dot surface. Different ligands are orderly adsorbed on the quantum dot surface, and active functional groups are directionally exposed, simultaneously completing the reconstruction of the surface ligand layer and the modification of functional sites, forming multi-ligand modified quantum dots, reserving reactive centers for subsequent covalent cross-linking. Moreover, since the chain segment polarity of the second and third ligands matches that of the first ligand (for example, the acrylate chain segment of the second ligand has a similar polarity to the PEG chain segment of the first ligand), the dispersion effect of the first ligand is not destroyed.

[0028] During the curing process, that is, when the system enters the curing stage, the first active functional group of the second ligand undergoes a copolymerization reaction with the resin monomer to construct a cross-linked network, "locking" the quantum dots into the polymer cross-linked network. For example, the acrylic group of the second ligand can form C-C covalent bonds with the acrylic resin monomer, making the quantum dots one of the "nodes" in the cross-linked network, rather than independent "fillers." This transformation greatly enhances the binding force between the quantum dots and the resin system, making them more stable in the resin system. Moreover, the polar segment of the first ligand still plays a role in the curing stage, and its compatibility with the resin system can reduce the aggregation of quantum dots caused by "phase separation" during the curing process, ensuring that the cross-linking and anchoring reactions occur uniformly. At the same time, during the curing process, the second active functional group of the third ligand undergoes a specific reaction with the resin monomer, achieving precise covalent anchoring of the quantum dots and the resin monomer, transforming the quantum dots from an "encapsulated state" to an "anchored state," further strengthening the binding stability. The first active functional group of the second ligand and the second active functional group of the third ligand can be selected according to the type of resin monomer in the specific resin system, so as to be suitable for different types of resin systems or adhesive systems.

[0029] The curing method described above includes, for example, ultraviolet light curing, thermosetting, or catalyst curing. Photoinitiators include, for example, any one or a combination of two or more of the following: di-tert-butyl peroxide, benzoyl peroxide, ferrocene aramid salts, aryl diazonium salts, macromolecular benzophenone, azobisisobutyronitrile, diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, and trimethylbenzoyl-diphenylphosphine oxide. Thermosetting agents include, for example, triethylenetetramine, and catalysts include, for example, p-toluenesulfonic acid.

[0030] In one embodiment, taking a phenolic resin system as an example, when the resin monomer is a phenolic resin monomer, the first active functional group of the second ligand includes a hydroxymethyl (-CH2OH) functional group, and the second active functional group of the third ligand includes a phenolic hydroxyl or aldehyde (-CHO) functional group; in the presence of a suitable catalyst (e.g., an acidic or basic catalyst) or under heating triggering, the hydroxymethyl group reacts with the aromatic ring active site (ortho or para) of the phenolic resin monomer or the aromatic ring active site of the third ligand. The hydroxymethyl group undergoes etherification or dehydration condensation at the ortho or para position. It undergoes etherification with the aromatic ring, breaking the C-OH bond to form a -CH2-O- ether bond, or undergoes dehydration condensation with the phenolic hydroxyl / aldehyde group to remove H2O, constructing a methylene bridge (-CH2-). This forms an ether bond (-CH2-O-) or a methylene bridge (-CH2-), thereby fixing the quantum dots and embedding them into the phenolic resin crosslinking network through these covalent bonds. This achieves irreversible anchoring of the quantum dots while improving interfacial bonding and network stability. The acidic catalyst is, for example, p-toluenesulfonic acid, and the basic catalyst is, for example, sodium hydroxide. The heating temperature is, for example, 80~120℃.

[0031] In one embodiment, taking an acrylic resin system as an example, when the resin monomer is an acrylic / methacrylic acid resin monomer, the first active functional group of the second ligand includes an acrylic or methacrylate functional group that can participate in addition polymerization, and the second active functional group of the third ligand includes a methacrylate functional group, an allyl functional group, or other copolymerizable unsaturated olefin functional groups. In the presence of a photoinitiator, a thermal initiator, or a free radical initiator, the acrylic / methacrylate functional group of the second ligand, the second active functional group of the third ligand, and the olefin bond of the resin monomer are homolytically cleaved into active free radicals. The second ligand, the third ligand, and the resin monomer form a covalent backbone or cross-linked structure through free radical polymerization / copolymerization, thereby covalently embedding and anchoring the quantum dots in the acrylic resin cross-linked network in a copolymerization manner. The photoinitiator is, for example, benzophenone, and the thermal initiator is, for example, azobisisobutyronitrile (AIB).

[0032] In one embodiment, taking an epoxy resin system as an example, when the resin monomer is an epoxy resin monomer, the first active functional group of the second ligand includes an epoxy functional group, such as a glycidyl epoxy group; the second active functional group of the third ligand includes an amino or carboxyl functional group, such as a primary aminopropyl ester; under catalysis or heating triggering, the amino or carboxyl functional groups undergo ring-opening addition with the epoxy functional group in a nucleophilic manner, forming β-hydroxyamine bonds or β-hydroxy ester bonds respectively, thereby covalently anchoring the quantum dots to the epoxy resin crosslinking network by forming addition products. The catalyst is, for example, triethylamine or imidazole catalyst, and the heating temperature is, for example, 80~120℃.

[0033] In one embodiment, when the resin monomer is a polyamide resin system containing an amide structure or a resin system involving isocyanate reaction, the first active functional group of the second ligand includes an isocyanate (-NCO) functional group, which has high reactivity, and the second active functional group of the third ligand includes a hydroxyl or amino functional group; the isocyanate functional group reacts with the hydroxyl functional group to form a urethane bond (-NH-CO-O-), or reacts with the amino functional group to form a urea bond (-NH-CO-NH-), thereby anchoring the quantum dots and embedding them into the resin crosslinking network through the covalent bond.

[0034] In another embodiment, the third ligand is a silane hydrolysis product with the general formula Y(CH2). nSi(OH)3, where n is a natural number greater than or equal to 1; Y is a non-hydrolyzable organic functional group that can specifically react with the resin monomer; the Si(OH)3 functional group in the hydrolysis product is retained for binding and protecting the quantum dot material. The resin monomer has an unsaturated functional group with an unsaturation degree of 1, which can undergo an addition reaction with the non-hydrolyzable organic functional group in the silane hydrolysis product to introduce silanol groups onto the resin monomer, while retaining the silanol groups for subsequent quantum dot binding and stabilization protection.

[0035] In this embodiment, the first active functional group of the second ligand is selected from one or more of acrylate, epoxy, vinyl, and isocyanate groups, providing a crosslinking group. The resin system includes the above-mentioned silane hydrolysis product, the above-mentioned resin monomer, a first solvent, and a surfactant. The first solvent includes, for example, any one or a combination of two or more of propyl methacrylate, isobornyl acrylate, octadecyl acrylate, dipropylene glycol diacrylate, propoxylated glycerol triacrylate, tripropylene glycol diacrylate, ethylene glycol diacrylate, propylene glycol diacrylate, trimethylolpropane triacrylate, pentaerythritol triacrylate, dipentaerythritol pentaacrylate, propylene glycol methyl ether acetate, N-methylpyrrolidone, and butyl acetate. The surfactant is, for example, polyether-modified dimethylsiloxane. The above-mentioned hydrolysis product and acrylic resin monomer and solvent (e.g., propylene glycol methyl ether acetate) are mixed, and a trace amount of polyether-modified dimethylsiloxane is added. After mixing evenly and reacting at 60°C for 24 hours, a reaction solution is obtained. The reaction solution was rotary evaporated to remove propylene glycol methyl ether acetate until the weight of the reaction solution decreased by about 50%. Then the rotary evaporation was stopped to obtain a composite material (i.e., a resin system).

[0036] In this embodiment, the silane hydrolysis product is prepared by hydrolyzing a silane coupling agent under preset temperature and pH conditions, and the general formula of the silane coupling agent is Y(CH2). n In SiX3, Y is a non-hydrolyzable organic functional group, such as phenyl, vinyl, epoxy, amino, mercapto, etc., which often chemically bonds with the organic functional groups in the adhesive matrix resin; X is a hydrolyzable functional group, such as chloro, methoxy, ethoxy, etc., which are easily hydrolyzed into silanols (silanols) under weakly alkaline (pH 9~12) or weakly acidic (pH 4~6.5) conditions, and react with oxides or hydroxyl groups on the surface of inorganic materials (glass, silica, metal, clay, etc.) to form stable silicon-oxygen bonds.

[0037] The preset pH value is 6~12, and the preset temperature is less than or equal to 80℃.

[0038] Understandably, the silane coupling agent Y(CH2) n SiX3 reacts with water according to the following reaction formula (1).

[0039] Reaction formula (1) Reaction formula (2) As can be seen from reaction formulas (1) and (2), the Y functional group of the hydrolysis product and the unsaturated functional group of the resin monomer, such as C=C, can undergo an addition reaction in a 2:1 ratio to introduce silanol groups onto the resin monomer. In this embodiment, the C=C double bond is taken as an example. In actual reactions, the C=C double bond can also be an unsaturated functional group with an unsaturation degree of 1, such as the C=O double bond, C=N double bond, or epoxy alkyl group.

[0040] In this embodiment, the silane coupling agent is selected from one or a mixture of two or more of γ-methacryloxypropyltrimethoxysilane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, and glycidyl etheroxypropyltrimethoxysilane.

[0041] In this embodiment, the resin monomer is selected from one or a mixture of two or more of acrylic resin monomers, epoxy resin monomers, phenolic resin monomers, and polyamide resin monomers. Furthermore, the acrylic resin monomer, epoxy resin monomer, phenolic resin monomer, and polyamide resin monomer each contain one or more of the following groups: carboxyl, hydroxyl, amino, acyl chloride, and C=C groups.

[0042] Furthermore, in this invention, the quantum dots are selected from one or a mixture of several of CdSe, CdS, ZnS, CdZnSe, CdZnS, CdZnSeS, ZnSeS, ZnSe, CuInS, CuInSe, InP, and InZnP. In one embodiment, the surface of the quantum dots further has an initial ligand, which is selected, for example, from one or a combination of two or more of the following categories: (A) Straight-chain saturated fatty acids with a carbon chain length of C14~C18; (B) Straight-chain monounsaturated fatty acids with a carbon chain length of C14~C18 and containing one cis double bond; (C) Low molecular weight fatty amines, including tributylamine, tri-n-octylamine and C12~C18 straight-chain primary amines; (D) Straight-chain or branched oleamide derivatives containing amino or alkyl-substituted amine groups, used for quantum dot surface stabilization; Furthermore, the initial ligand forms a coordination bond with the quantum dot surface and can be partially replaced or covalently anchored with the second and third ligands.

[0043] Preferably, the mass ratio of the quantum dot, the first ligand, the second ligand, and the third ligand is (1–20): (0.5–5): (0.5–5): (0.1–3), wherein the first ligand promotes uniform dispersion of the quantum dot in the resin system; the second and third ligands form a cross-linked network with the resin system during curing, anchoring the quantum dot at specific nodes of the cross-linked network. Furthermore, the above mass ratio can be appropriately adjusted according to the surface coverage of the quantum dot and the resin system to obtain optimal dispersibility and fluorescence performance.

[0044] Please see Figure 1 , Figure 1 This is a schematic flowchart of a patterned preparation method for a multifunctional modified quantum dot composite adhesive material according to an embodiment of the present invention; a second aspect of the present invention also provides a patterned preparation method for the multifunctional modified quantum dot composite adhesive material as described above, the patterned preparation method comprising the following steps: Step S1, Preparation of multi-ligand modified quantum dots: Quantum dots, along with a first ligand, a second ligand, and a third ligand, are added to a second solvent. The mixture is stirred at room temperature for 2–4 hours, then heated to 45–60°C and reacted for 4–10 hours. The mixture is then centrifuged at 6000–8000 rpm and washed 2–3 times to obtain multi-ligand modified quantum dots. The mass ratio of the quantum dots, the first ligand, the second ligand, and the third ligand is (1–20): (0.5–5): (0.5–5): (0.1–3). The second solvent is, for example, any one of toluene, DCM (dichloromethane), or IPA (isopropanol).

[0045] In step S1, the second solvent dissolves the three ligands and ensures uniform dispersion of the quantum dots, preventing aggregation and providing a homogeneous environment for contact between the ligands and the quantum dot surface. Stirring at room temperature for 2-4 hours allows the first, second, and third ligands to diffuse sufficiently around the quantum dots, making initial contact with the initial ligands on the quantum dot surface (such as oleic acid and thioglycolic acid used in synthesis), thus creating conditions for subsequent ligand exchange. Heating to 45-60℃ significantly accelerates the ligand exchange rate: the coordination bonds of the initial ligands on the quantum dot surface are weakened, while the first, second, and third ligands, due to their stronger coordination ability or higher compatibility with the metal atoms on the quantum dot surface, gradually replace the initial ligands. Centrifugation removes unexchanged free ligands, a small amount of unexchanged initial ligands, and solvent impurities, ensuring that only the target three ligands (first, second, and third ligands) remain on the quantum dot surface, preventing impurities from interfering with subsequent reactions. The purpose of washing 2-3 times is to thoroughly remove impurities, prevent free ligands from interfering with the subsequent composite reaction with the resin system, and at the same time make the surface state of multi-ligand modified quantum dots more uniform, thereby improving the stability of the subsequent composite adhesive.

[0046] Step S1 achieves the substitution modification of the quantum dot surface by the first ligand, the second ligand, and the third ligand through solvent dispersion and temperature control, ultimately forming a stable modified layer with multi-ligand synergistic adsorption.

[0047] In the above steps, the specific volume of the second solvent can be adjusted according to the total mass of the quantum dots and the first, second, and third ligands to ensure a suitable solid-liquid ratio, which guarantees the dispersion effect while avoiding excessive solvent that would increase the centrifugation burden. Preferably, the volume of the second solvent is 50-200 mL.

[0048] Step S2, preparation of composite adhesive: The obtained multi-ligand modified quantum dots are dispersed in the resin system (one of acrylic resin system, phenolic resin system, epoxy resin system or polyamide resin system), sonicated for 5-15 min and stirred for 20-30 min to form a uniform composite adhesive. The mass of the composite adhesive is used as the total mass, and the mass percentage of the multi-ligand modified quantum dots is 0.1-10 wt%. A photoinitiator or catalyst may be added in this step for subsequent curing.

[0049] The mass percentage of multi-ligand modified quantum dots is controlled between 0.1% and 10 wt% to balance dispersion and subsequent performance. Too low a concentration will result in insufficient quantum dot functionality (such as fluorescence and photoelectric properties) in the final film; too high a concentration will cause aggregation or fluorescence quenching due to the close proximity of the quantum dots, while also affecting the flowability and coating performance of the composite solution. Preferably, the mass percentage of multi-ligand modified quantum dots is 0.5 wt% to 5.0 wt%, which achieves a better balance between optical brightness, dispersion stability, and photolithography performance. More preferably, the mass percentage of multi-ligand modified quantum dots is 1.0 wt% to 3.0 wt%, which is suitable for thin-film luminescence / patterning photolithography applications.

[0050] Step S3, Thin film formation and curing: The composite adhesive is spin-coated onto a substrate, such as glass, PET, or a silicon wafer, with a wet film thickness of 10-50 μm. A cross-linked cured film is obtained by employing a corresponding curing method based on the resin system. The curing method can be, for example, ultraviolet (UV) curing with parameters such as 365-405 nm and 800-2000 mJ / cm²; or heat curing with parameters such as 50-150 °C and 5-60 min.

[0051] Step S4, photolithography patterning: A patterned quantum dot composite film layer is formed by exposing the film using a photomask and removing uncrosslinked areas using a developing solvent. The developing solvent, for example, is acetone / isopropanol / acetone:IPA in a volume ratio of 3:1.

[0052] Preferably, post-baking (50~100℃, 5~20min) can further promote the reaction of residual incompletely cross-linked active sites, increase the cross-linking density of the film layer, and enhance the adhesion and mechanical strength of the film layer to the substrate, ultimately forming a quantum dot composite film with clear patterns and stable performance.

[0053] Before mixing the quantum dots with the first ligand, the second ligand, and the third ligand, the quantum dots may be dispersed in a first solvent, such as at least one of chloroform, chlorobenzene, toluene, n-hexane, n-octane, tetrahydrofuran, N,N-dimethylformamide, N-methylformamide, formamide, dimethyl sulfoxide, acetonitrile, and acetone.

[0054] The following examples 1-4 will specifically illustrate the patterning preparation process of the multifunctional modified quantum dot composite adhesive material provided by the present invention. Example 1: Patterned quantum dot composite film layer based on acrylic resin monomer

[0055] 1. Experimental materials: CdSe / ZnS red quantum dot raw material (8nm in diameter, with oleic acid as the initial ligand on the surface); First ligand (L1): hexadecylphosphonic acid; Second ligand (L2): methacrylate-mercaptopropionate; Third ligand (L3): glycidyl acrylate; Resin monomer: Acrylic resin monomer; Photoinitiators: Benzophenones.

[0056] 2. Operating Procedures (1) Preparation of multi-ligand modified quantum dots: QDs with oleic acid ligands on their surface, the first ligand, the second ligand and the third ligand were added to 150 ml of isoacetone solvent, wherein the mass ratio of quantum dots, the first ligand, the second ligand and the third ligand was 20: 5: 5: 3. After stirring at room temperature for 3 h, the temperature was raised to 55 °C and reacted for 8 h. The mixture was centrifuged at 7000 rpm and washed 3 times to obtain multi-ligand modified quantum dots. (2) Preparation of composite adhesive: Disperse 1 wt% of multiligand modified quantum dots in PGMEA solvent, add acrylic resin monomer and photoinitiator (benzophenone), sonicate for 10 min and stir for 30 min to degas and form a uniform composite adhesive; (3) Thin film formation and curing: The composite adhesive is spin-coated onto the glass substrate, and the wet film thickness is 30 μm; it is then cured by ultraviolet light, with UV curing parameters such as 385 nm and 1500 mJ / cm², to obtain a cross-linked cured film layer. (4) Photolithography patterning: Expose using a photolithography mask, develop (where the developing solvent is acetone / isopropanol / acetone:IPA with a volume ratio of 3:1) to remove uncrosslinked areas, and then perform post-baking (80℃, 15min) to enhance the mechanical strength of the film layer and form a red light patterned quantum dot composite film layer.

[0057] 3. Reaction Mechanism Photoinitiated free radical generation: After UV irradiation, benzophenone photoinitiators absorb photons and decompose, generating active free radicals (such as benzoyl free radicals). Free radical copolymerization and cross-linking: Active free radicals initiate the free radical copolymerization reaction between the acrylate groups of the second ligand (methacrylic acid-mercaptopropionate) and the third ligand (glycidyl acrylate) and the unsaturated olefin bonds of the acrylic resin monomer, forming a covalent backbone or cross-linked structure. The quantum dots are "anchored" to the resin monomer through the covalent bonds of the ligands and are permanently embedded in the cross-linked network of the acrylic resin.

[0058] 4. Performance Testing The performance of the obtained red-light patterned quantum dot composite film was tested, and the results are as follows: (1) Photoluminescence quantum efficiency (PLQY): 95% retention rate after curing; (2) Heat resistance: After heat treatment at 120℃ for 100h, the luminous intensity retention rate is 100%; (3) Pattern resolution: better than 2μm, with no obvious edge diffusion. Example 2: Patterned quantum dot composite film layer based on epoxy resin monomer

[0059] 1. Experimental materials InP / ZnS green quantum dots (with oleylamine as the initial ligand on the surface); L1: Phosphonic acid group-polyethylene glycol segment; L2: Glycidyl epoxy ligand; L3: Primary aminopropyl amino acid ester; Resin monomer: Bisphenol A type epoxy resin monomer; Curing agent: triethylenetetramine.

[0060] 2. Operating Procedures (1) Preparation of multi-ligand modified quantum dots: InP QDs with oleylamine ligands on the surface, the first ligand, the second ligand and the third ligand were added to 150 ml of isopropanone solvent, wherein the mass ratio of quantum dots, the first ligand, the second ligand and the third ligand was 10:3:3:2. After stirring at room temperature for 4 h, the temperature was raised to 45 °C and reacted for 10 h. After centrifugation at 6000 rpm and washing three times, multi-ligand modified quantum dots were obtained. (2) Preparation of composite adhesive: Disperse 3 wt% multiligand modified quantum dots into epoxy resin system, sonicate for 15 min and stir for 20 min to degas and form a uniform composite adhesive; (3) Thin film formation and curing: The composite adhesive is spin-coated onto the glass substrate, and the wet film thickness is 30 μm; it is then cured by UV-assisted heat curing. The UV curing parameters are: 385 nm, 1500 mJ / cm², and the heat curing parameters are, for example: 120 °C, 60 min, to obtain the cross-linked cured film layer. (4) Photolithography patterning: Expose using a photolithography mask, develop (where the developing solvent is acetone / isopropanol / acetone:IPA in a volume ratio of 3:1) to remove uncrosslinked areas, and then perform post-baking (80℃, 15min) to enhance the mechanical strength of the film layer and form a patterned quantum dot composite film layer.

[0061] 3. Reaction Mechanism UV irradiation can accelerate the rate of nucleophilic ring-opening reaction. The amino group of the curing agent triethylenetetramine and the primary amino group of the third ligand are both nucleophiles, which will actively attack the epoxy group of the second ligand and the epoxy group of the epoxy resin monomer, thus initiating the ring-opening of the epoxy group.

[0062] After the ring-opening reaction, the amine group combines with the epoxy group to form a β-hydroxyamine bond. At the same time, the epoxy resin monomer achieves intermolecular cross-linking through the "epoxy-amine" ring-opening addition, constructing a three-dimensional cross-linking network. The quantum dots are permanently covalently anchored in the epoxy resin cross-linking network through the covalent bonds (β-hydroxyamine bonds) formed by the epoxy group of the second ligand, the primary amine group of the third ligand, and the resin monomer / curing agent.

[0063] 4. Performance Testing The performance of the patterned quantum dot composite film was tested, and the results are as follows: (1) Photoluminescence stability: After being excited by 450nm blue light for 1000h, the attenuation is less than 10%; (2) Heat resistance: After heat treatment at 150℃ for 200h, the luminous intensity retention rate is 95%; (3) Film uniformity: No QDs aggregation phenomenon, and smooth surface. Example 3: Patterned quantum dot composite film layer based on phenolic resin monomer

[0064] 1. Experimental materials CdZnSeS green quantum dots (10nm in diameter); L1: Carboxyl-dodecane chain; L2: Hydroxymethylphenyl ligand; L3: p-Hydroxybenzaldehyde derivative; Resin monomer: Phenolic resin monomer; Catalyst: p-Toluenesulfonic acid.

[0065] 2. Operating Procedures (1) Preparation of multi-ligand modified quantum dots: CdZnSeS QDs, the first ligand, the second ligand and the third ligand were added to 200 ml of isopropanone solvent, wherein the mass ratio of quantum dots, the first ligand, the second ligand and the third ligand was 2:1:1:1. After stirring at room temperature for 4 h, the temperature was raised to 60 °C and reacted for 10 h. The mixture was centrifuged at 8000 rpm and washed 3 times to obtain multi-ligand modified quantum dots. (2) Preparation of composite adhesive: 10 wt% of multi-ligand modified quantum dots are dispersed in phenolic resin monomer, p-toluenesulfonic acid catalyst is added, ultrasonication is performed for 10 min and stirring is performed for 30 min to remove bubbles and form a uniform composite adhesive. (3) Thin film formation and curing: The composite adhesive was spin-coated onto the glass substrate, the wet film thickness was 30 μm, and the heat curing was carried out at 120℃ for 60 min to obtain a cross-linked cured film layer; (4) Photolithography patterning: Expose using a photolithography mask, develop (where the developing solvent is acetone / isopropanol / acetone:IPA with a volume ratio of 3:1) to remove uncrosslinked areas, and then perform post-baking (80℃, 15min) to enhance the mechanical strength of the film layer and form a patterned quantum dot composite film layer.

[0066] 3. Reaction Mechanism During the thermosetting process, p-toluenesulfonic acid acts as an acidic catalyst, activating the reactivity of the hydroxymethyl (-CH2OH) group of the second ligand, while simultaneously promoting the dissociation of the active sites (ortho or para) on the aromatic ring of the phenolic resin monomer, thus creating conditions for the reaction.

[0067] The hydroxymethyl group reacts with the active site of the aromatic ring of the phenolic resin monomer, or with the phenolic hydroxyl / aldehyde group of the third ligand, in two ways: one is etherification to form an ether bond (-CH2-O-), and the other is dehydration condensation to form a methylene bridge (-CH2-). These two types of covalent bonds drive the cross-linking between phenolic resin monomer molecules, constructing a three-dimensional cross-linked network. Quantum dots are permanently anchored and embedded in the cross-linked structure of phenolic resin through covalent bonds formed between the ligand and the phenolic resin monomer.

[0068] 4. Performance Testing The performance of the obtained patterned quantum dot composite film was tested, and the results are as follows: (1) Solvent resistance: After soaking in a toluene-ethanol mixture and IPA for 24 h, there was no significant loss of luminescence; (2) Thermal stability: After heat treatment at 200℃ for 20 hours, the strength is maintained at 90%; (3) Photolithography resolution: up to 1μm, suitable for high-resolution display applications. Example 4: Patterned quantum dot composite film layer based on acrylic resin monomer

[0069] 1. Experimental materials CdSe / ZnS red quantum dot raw material (8nm in diameter, with oleic acid as the initial ligand on the surface); First ligand (L1): hexadecylphosphonic acid; Second ligand (L2): methacrylate-mercaptopropionate; Third ligand (L3): Hydrolysis product of silane coupling agent; Resin monomer: Acrylic resin monomer; Photoinitiator: Benzoyl peroxide (BPO).

[0070] 2. Operating Procedures (1) Preparation of multi-ligand modified quantum dots: γ-methacryloxypropyltrimethoxysilane (also known as: KH-570 silane coupling agent) was added to 70% ethanol aqueous solution; stirred evenly to form a mixed solution; the pH of the mixed solution was adjusted to 8; the temperature was 60℃; and the reaction was carried out for 6h. After the reaction was completed, the mixture was allowed to stand, the supernatant was removed, and the mixture of the lower precipitate was centrifuged and filtered at 7500r / min for 15min to obtain a solid hydrolysis product (i.e., L3). CdZnSeS QDs, the first ligand, the second ligand and the third ligand were added to 150ml of isoacetone solvent, wherein the mass ratio of quantum dots, the first ligand, the second ligand and the third ligand was 15: 4: 4: 2. After stirring at room temperature for 3h, the temperature was raised to 55℃ and the reaction was carried out for 8h. The mixture was centrifuged at 7000 rpm and washed 3 times to obtain multi-ligand modified quantum dots. (2) Preparation of composite adhesive: 20 parts by weight of the above hydrolysis product, 20 parts by weight of acrylic resin monomer, and 58 parts by weight of propylene glycol methyl ether acetate (PGMEA) were mixed and 2 parts by weight of polyether modified dimethylsiloxane were added. The mixture was stirred evenly at 60°C for 24 hours to obtain a reaction solution. The reaction solution was rotary evaporated to remove propylene glycol methyl ether acetate until the weight of the reaction solution decreased by about 50%. The rotary evaporation was then stopped to obtain a composite material (i.e., a resin system). 3 wt% of multiligand-modified quantum dots were added to the composite material, and the mixture was sonicated for 10 min and stirred for 30 min to remove bubbles and form a uniform composite adhesive. (3) Thin film formation and curing: The composite adhesive is spin-coated onto the glass substrate, the wet film thickness is 30 μm, and UV curing is performed at 365~405 nm and 800~2000 mJ / cm² to obtain a cross-linked cured film layer; (4) Patterning: Photolithography patterning: Expose using a photolithography mask, develop (where the developing solvent is acetone / isopropanol / acetone:IPA with a volume ratio of 3:1) to remove uncrosslinked areas, and then perform post-baking (80℃, 15min) to enhance the mechanical strength of the film layer and form a patterned quantum dot composite film layer.

[0071] 3. Reaction Mechanism The methacryloyloxy group in γ-methacryloyloxypropyltrimethoxysilane can undergo an addition reaction with acrylic resins via free radical polymerization. Acrylic resins typically contain multiple double bonds of acrylic acid or methacrylic acid, which can copolymerize with the double bonds in γ-methacryloyloxypropyltrimethoxysilane to form a cross-linked structure. These reactions are usually carried out with an initiator (such as a peroxide) and at an appropriate temperature. Examples of the reactions are as follows: Photoinitiation stage (taking benzoyl peroxide (BPO) as an example): BPO → 2C6H5COO· Reaction conditions: UV light 365~405nm, 800~2000mJ / cm², BPO as initiator decomposes to generate active free radicals (benzoyloxy radicals).

[0072] Chain initiation (free radical attack on unsaturated alkene bonds): C6H5COO·+CH2=CH-R→C6H5COO-CH2-CH·R Chain growth (co-aggregation of the main chain): C6H5COO-CH2-CH·R+CH2=CH-R'→ C6H5COO-CH2-CH(R)-CH2-CH·R' Wherein, R and R' can be γ-methacryloyloxypropyltrimethoxysilane or acrylic acid monomer. The methacryloyloxy groups of the second and third ligands undergo free radical copolymerization with the unsaturated olefin bonds of the acrylic resin monomer to form a copolymer backbone. For example, L2 has a copolymer bond of -CH2−C(CH3)-COO- with the acrylic resin monomer, and a copolymer bond of -CH2-CH(COOR)- with the acrylic resin monomer; L3 has a copolymer bond of -CH2-C(CH3)-COO-(CH2)3-Si- with the acrylic resin monomer.

[0073] Chain termination (active chain termination): C6H5COO-CH2-CH·R+C6H5COO-CH2-CH·R'→ C6H5COO-CH2-CH(R)-CH2-CH(R')-C6H5COO Ultimately, a stable acrylic acid copolymer backbone structure is formed.

[0074] Quantum dots are covalently and firmly embedded in the cross-linked network of acrylic resin through the synergistic effect of L2, L3 covalent bonds (copolymer bonds) and siloxane bonds with the resin system. This ensures the stability of the quantum dots and improves the structural density and mechanical strength of the film.

[0075] 4. Performance Testing The performance of the patterned quantum dot composite film was tested, and the results are as follows: (1) Solvent resistance: After soaking in a toluene-ethanol mixture and IPA for 24 h, there was no significant loss of luminescence; (2) Thermal stability: After heat treatment at 200℃ for 20 hours, the strength is maintained at 90%; (3) Photolithography resolution: up to 2μm, suitable for high-resolution display applications. Comparative Example 1:

[0076] Objective: To prepare composite photoresists containing quantum dots modified with a single organic ligand and to verify the feasibility of film formation and patterning.

[0077] 1. Materials: Quantum dots (QDs, CdSe / ZnS with surface modified by a single oleic acid / oleylamine ligand, solid dispersion in toluene, solid content 10 wt%) Acrylic photoresist (preparation solution, solid content 20wt%, suitable for spin coating); Reactive diluent (IBOA, optional) Photoinitiator (Irgacure 819 or BAPO, add according to the resin's recommended dosage) Solvent: Toluene or methyl ethyl ketone (compatible with photoresist) Developer: Acetone or isopropanol (according to photoresist instructions) Formulation (example per 100g total): Acrylic photoresist stock solution (20wt% solids): 80.0g, Quantum dot dispersion (10wt% QDs in toluene): 10.0g (equivalent to approximately 1.0wt% QDs in the final system), Reactive diluent (IBOA): 9.0g (for adjusting viscosity), Photoinitiator (Irgacure 819): 1.0g.

[0078] 2. Preparation steps: (1) Slowly add 10g of quantum dot dispersion (10wt%) to the equivalent amount of 20g of acrylic solid solution (pre-mix a small portion of photoresist mother liquor) while stirring and adding dropwise to reduce the risk of agglomeration caused by local concentration abrupt changes.

[0079] (2) Stir magnetically for 30 minutes (500 rpm), then place in an ice bath and sonicate for 5-10 minutes (intermittently to avoid temperature rise) to promote dispersion.

[0080] (3) Add the remaining photoresist mother liquor and reactive diluent, and continue mechanical stirring for 20 minutes to ensure uniformity.

[0081] (4) Degassing: Degas for 10-20 minutes under reduced pressure to avoid pinholes during spin coating.

[0082] (5) Use immediately after filtration (0.45μm PTFE filter) or store in an inert atmosphere for a short period of time (avoid oxygen and light to prevent prepolymerization or quenching).

[0083] 3. Film formation and photolithography process: (1) Spin-coat composite adhesive onto a clean silicon / glass substrate: 3000 rpm, 30 s (a ~1 μm film can be obtained).

[0084] (2) Soft baking: 60℃, 2min (to remove solvent and avoid prolonged high temperature).

[0085] (3) Exposure: UV (385nm), dose 150–300mJ / cm².

[0086] (4) Development: Development (where the development solvent is acetone / isopropanol / acetone:IPA in a volume ratio of 3:1) removes the uncrosslinked areas, washes with water and dries with nitrogen.

[0087] (5) Post-baking / curing: 80℃, 15min.

[0088] 4. Performance Testing The performance of the patterned quantum dot composite film was tested, and the results are as follows: (1) Solvent resistance: After immersion in a toluene-ethanol mixture and IPA for 24 hours, the light decay was 30%; (2) Thermal stability: After heat treatment at 200℃ for 20 hours, the strength is maintained at 50%; (3) Photolithography resolution: up to 2μm, suitable for high-resolution display applications.

[0089] Please see below. Figure 2 and Figure 3 , Figure 2 This is a schematic diagram of the blue light aging test of the patterned quantum dot composite adhesive film layer prepared in Examples 1-4 and Comparative Example 1 of the present invention. Figure 3 These are schematic diagrams illustrating the photolithographic patterning effects of the patterned quantum dot composite adhesive film layers prepared in Examples 1-4 and Comparative Example 1 of the present invention, wherein... Figure 3 The four images in the first row correspond to Examples 1-4 from left to right, and the images in the second row correspond to Example 1.

[0090] As can be seen from the performance test results of Examples 1-4 and Comparative Example 1, the quantum dot composite adhesive film prepared by the patterning preparation method of the multifunctional modified quantum dot composite adhesive material of the present invention not only has high photoluminescence quantum efficiency (PLQY), high solvent resistance, and high thermal stability, but also has high photolithographic resolution.

[0091] Furthermore, a third aspect of the present invention provides a quantum dot light-emitting device, the quantum dot light-emitting device comprising a substrate and a quantum dot composite adhesive film layer disposed in cooperation with the substrate, the substrate comprising light-emitting units arranged in an array, the quantum dot composite adhesive film layer being formed on the substrate such that the light-emitting surface of the light-emitting units is covered by the quantum dot composite adhesive film layer, the quantum dot composite adhesive film layer being formed using the patterned preparation method of the multifunctional modified quantum dot composite adhesive material described above.

[0092] A fourth aspect of the present invention also provides a display device, the display device comprising the light-emitting device as described above.

[0093] In summary, this invention enhances the stability of quantum dots from multiple dimensions through the synergistic effect of a first ligand, a second ligand, and a third ligand. The first ligand provides hydrophobic / resinophilic interface regulation, ensuring uniform dispersion of quantum dots in solvents and resin systems, laying the foundation for subsequent modification. The first active functional group carried by the second ligand and / or the second active functional group carried by the third ligand selectively undergo addition, condensation, copolymerization, or ring-opening specific reactions with resin monomers or resin systems to form covalent bonds, constructing covalent connections between the quantum dot surface and the resin crosslinking network, thereby achieving covalent anchoring and embedding of the quantum dot resin crosslinking network. Moreover, through a customized ligand strategy, it can be adapted to different resin systems (acrylic resin system, epoxy resin system, phenolic resin system, polyamide resin system, etc.), ensuring that the quantum dots still maintain high fluorescence efficiency and long lifetime under complex environments. At the same time, because the quantum dots are uniformly distributed in the network and spatially confined, photo-induced / thermal quenching can be effectively reduced, improving luminescence uniformity and pattern clarity.

[0094] In practical applications, the advantages of the triligand synergistic modification strategy have been fully demonstrated. In quantum dot light-emitting devices (QLEDs), triligand-modified quantum dots can be uniformly dispersed in the resin matrix, forming a stable covalent network, enabling the device to maintain high luminous efficiency and long lifetime under continuous driving or high-temperature operating conditions. In sensor or optical detection applications, triligand-modified quantum dots, due to network embedding and interface stability, can maintain fluorescence stability in complex solution environments, improving detection accuracy and reliability.

[0095] The present invention has been described by the above-described embodiments; however, these embodiments are merely examples for implementing the present invention. Furthermore, the technical features involved in the different embodiments of the present invention described above can be combined with each other as long as they do not conflict with each other. It must be pointed out that the disclosed embodiments do not limit the scope of the present invention. On the contrary, any modifications and refinements made without departing from the spirit and scope of the present invention are within the scope of patent protection of the present invention.

Claims

1. A multifunctional modified quantum dot composite adhesive material, characterized in that, The quantum dot composite adhesive material includes quantum dots, a resin system, and multifunctional ligands. The resin system includes resin monomers, and the multifunctional ligands include: A first ligand, comprising a long-chain alkyl group, a polar solvent nucleophilic group, or a polar solvent nucleophilic group externally attached with a long-chain alkyl group, is used to promote the uniform dispersion of the quantum dots in the resin system. A second ligand, the second ligand containing a first active functional group, is adapted to the resin system; A third ligand, wherein the third ligand contains a second active functional group and is compatible with the resin system; During the curing process of the quantum dot composite adhesive, the first active functional group carried by the second ligand and / or the second active functional group carried by the third ligand selectively undergo addition, condensation, copolymerization or ring-opening specific reactions with the resin monomer or resin system to form covalent bonds, which are used to build covalent connections between the quantum dot surface and the resin crosslinking network, thereby realizing the covalent anchoring and embedding of the quantum dots. The reaction mode is dynamically adapted according to the resin system.

2. The quantum dot composite adhesive material with multiple functional modifications as described in claim 1, characterized in that, The first ligand is selected from one or more of hexadecylphosphonic acid, phosphonic acid-polyethylene glycol segments, carboxyl-dodecane chains, and sulfonic acid derivatives.

3. The quantum dot composite adhesive material with multiple functional modifications as described in claim 1, characterized in that, When the resin monomer is a phenolic resin monomer, the first active functional group includes a hydroxymethyl functional group, and the second active functional group includes a phenolic hydroxyl or aldehyde functional group; under the action of a catalyst or heating, the hydroxymethyl group can undergo etherification or dehydration condensation with the active site of the aromatic ring of the phenolic resin monomer or the third ligand to form an ether bond or a methylene bridge, thereby fixing the quantum dots and embedding them into the phenolic resin crosslinking network through the above covalent bonds; When the resin monomer is an acrylic / methacrylic acid resin monomer, the first active functional group includes an acrylic or methacrylate functional group that can participate in addition polymerization, and the second active functional group includes a methacrylate functional group, an allyl functional group, or other copolymerizable unsaturated olefin functional groups. In the presence of photoinitiator, thermal initiator, or free radical initiator, the second ligand, the third ligand, and the acrylic / methacrylic acid resin monomer form a covalent backbone or cross-linked structure through free radical polymerization / copolymerization reaction, thereby covalently embedding and anchoring the quantum dots in the acrylic / methacrylic acid resin cross-linked network in a copolymerization manner. When the resin monomer is an epoxy resin monomer, the first active functional group includes an epoxy functional group, and the second active functional group includes an amino or carboxyl functional group; under catalytic or heating conditions, the amino or carboxyl functional group undergoes ring-opening addition with the epoxy functional group in a nucleophilic manner to form β-hydroxyamine bonds or β-hydroxy ester bonds, respectively, thereby covalently fixing the quantum dots in the epoxy resin crosslinking network by forming addition products; When the resin system is a polyamide resin system containing an amide structure or a resin system involving isocyanate reaction, the first active functional group includes an isocyanate functional group, and the second active functional group includes a hydroxyl functional group or an amino functional group; the isocyanate functional group reacts with the hydroxyl functional group to form a urethane bond, or reacts with the amino functional group to form a urea bond, thereby anchoring the quantum dots in the resin crosslinking network through covalent bonds.

4. The quantum dot composite adhesive material with multiple functional modifications as described in claim 1, characterized in that, The third ligand is a silane hydrolysis product, and the general formula of the silane hydrolysis product is Y(CH2). n Si(OH)3, where n is a natural number greater than or equal to 1; Y is a non-hydrolyzable organic functional group that can undergo specific reactions with the resin monomer; the Si(OH)3 functional group in the silane hydrolysis product is retained for binding and protecting the quantum dot material; the resin monomer has an unsaturated functional group with an unsaturation degree of 1, which can undergo an addition reaction with the non-hydrolyzable organic functional group in the silane hydrolysis product to introduce silanol groups onto the resin monomer, while retaining the silanol groups for subsequent quantum dot binding and stabilization protection; The first active functional group of the second ligand is selected from one or more of acrylate, epoxy, vinyl, and isocyanate groups; The resin system includes the silane hydrolysis product, the resin monomer, the first solvent, and the surfactant.

5. The quantum dot composite adhesive material with multiple functional modifications as described in claim 4, characterized in that, The unsaturated functional groups of the resin monomer are selected from one or more of carbon-carbon double bonds, carbon-nitrogen double bonds, carbon-oxygen double bonds, and epoxy alkyl groups.

6. The quantum dot composite adhesive material with multiple functional modifications as described in claim 4, characterized in that, The resin monomer is selected from one or a mixture of two or more of acrylic resin monomers, epoxy resin monomers, phenolic resin monomers, and polyamide resin monomers.

7. The quantum dot composite adhesive material with multiple functional modifications as described in claim 4, characterized in that, The silane hydrolysis product is prepared by hydrolyzing a silane coupling agent under preset temperature and pH conditions, wherein the general formula of the silane coupling agent is Y(CH2). n SiX3, where X is a hydrolytic functional group.

8. The quantum dot composite adhesive material with multiple functional modifications as described in claim 7, characterized in that, The silane coupling agent is selected from one or a mixture of two or more of γ-methacryloxypropyltrimethoxysilane, γ-(2,3-epoxypropoxy)propyltrimethoxysilane, γ-mercaptopropyltriethoxysilane, and glycidyl etheroxypropyltrimethoxysilane.

9. The multifunctional modified quantum dot composite adhesive material as described in claim 1, characterized in that, The surface of the quantum dot has an initial ligand, which is selected from one or more of the following categories: (A) Straight-chain saturated fatty acids with a carbon chain length of C14~C18; (B) Straight-chain monounsaturated fatty acids with a carbon chain length of C14~C18 and containing one cis double bond; (C) Low molecular weight fatty amines, including tributylamine, tri-n-octylamine and C12~C18 straight-chain primary amines; (D) Straight-chain or branched oleamide derivatives containing amino or alkyl-substituted amine groups, used for quantum dot surface stabilization; The initial ligand forms a coordination bond with the surface of the quantum dot and can be partially replaced or covalently anchored with the second and third ligands.

10. The multifunctional modified quantum dot composite adhesive material as described in claim 1, characterized in that, The quantum dots are selected from one or a mixture of several of CdSe, CdS, ZnS, CdZnSe, CdZnS, CdZnSeS, ZnSeS, ZnSe, CuInS, CuInSe, InP, and InZnP.

11. The multifunctional modified quantum dot composite adhesive material as described in claim 1, characterized in that, The curing process includes ultraviolet light curing, thermal curing, or catalyst curing.

12. The multifunctional modified quantum dot composite adhesive material as described in claim 1, characterized in that, The mass ratio of the quantum dot, the first ligand, the second ligand, and the third ligand is (1–20): (0.5–5): (0.5–5): (0.1–3).

13. A method for patterning a multifunctional modified quantum dot composite adhesive material as described in any one of claims 1-12, characterized in that, The patterning preparation method includes the following steps: Step S1, preparation of multi-ligand modified quantum dots: add quantum dots, first ligand, second ligand and third ligand to 50~200 mL of second solvent, stir at room temperature for 2~4 h, then heat to 45~60℃ and react for 4~10 h, centrifuge at 6000~8000 rpm and wash 2~3 times to obtain multi-ligand modified quantum dots; Step S2, preparation of composite adhesive: The obtained multi-ligand modified quantum dots are dispersed in the resin system, sonicated for 5-15 min and stirred for 20-30 min to form a uniform composite adhesive; and the mass percentage of the multi-ligand modified quantum dots is 0.1-10 wt%, based on the mass of the composite adhesive. Step S3, film formation and curing: Spin-coating the composite adhesive onto the substrate, the wet film thickness is 10~50μm; curing is carried out according to the resin system using the curing method to obtain the cross-linked cured film layer; Step S4, Photolithography Patterning: Expose using a photolithography mask, develop to remove uncrosslinked areas, and form a patterned quantum dot composite film layer.

14. A quantum dot light-emitting device, characterized in that, The quantum dot light-emitting device includes a substrate and a quantum dot composite adhesive film layer disposed in conjunction with the substrate. The substrate includes light-emitting units arranged in an array. The quantum dot composite adhesive film layer is formed on the substrate such that the light-emitting surface of the light-emitting unit is covered by the quantum dot composite adhesive film layer. The quantum dot composite adhesive film layer is characterized in that it is formed by the patterning preparation method of the multifunctional modified quantum dot composite adhesive material as described in claim 13.

15. A display device, characterized in that, The display device includes the quantum dot light-emitting device as described in claim 14.

Images