Failure self-repairing quantum dot film and preparation method thereof

Abstract

The invention discloses a failure self-repairing quantum dot film and a preparation method thereof, and relates to the field of optical films for display. The failure self-repairing quantum dot film comprises an upper barrier film, a quantum dot adhesive layer and a lower barrier film, by introducing the self-repairing functional monomer, the failure self-repairing quantum dot film has good failure improvement and aging resistance, and has practical value for improving the use reliability and prolonging the service life.

Description

Technical Field

[0001] This invention relates to the field of optical thin films, and mainly to a self-healing quantum dot film and its preparation method. Technical Background

[0002] Quantum dots are low-dimensional semiconductor materials at the nanoscale, with all three dimensions smaller than twice the exciton Bohr radius of the corresponding semiconductor materials. Common examples include II-VI and III-V group compounds such as CdS, CdSe, and InP. Due to the quantum confinement effect, quantum dots possess a discrete energy level structure, can accommodate a small number of electron-hole pairs, and have a charge that is an integer multiple of the elementary charge. Under external light and electrical excitation, the emission wavelength of quantum dots is tunable with size. By controlling the particle size, high-purity luminescence across the entire visible spectrum can be achieved. They also exhibit good stability and long lifetime, making them widely used in displays, bioimaging, and photovoltaics.

[0003] Since the concept of “Vitrimer” was proposed, chemical bonds with dynamic exchange properties have been continuously developed, and more technical solutions for self-healing polymers have been developed.

[0004] CN108440740A discloses a reversible self-healing epoxy resin and its preparation, recycling and remodeling method. The reversible disulfide bond used has a fast exchange reaction rate under mild conditions and can achieve a self-healing efficiency of over 95%.

[0005] CN108586708A discloses a thermally reversible self-healing epoxy resin and its preparation method, which achieves self-repair of epoxy resin through the Diels-Aider reverse reaction.

[0006] CN111499837A discloses a self-healing in-situ fluorescent tracer type heat-resistant and weather-resistant epoxy resin and its preparation method, which achieves self-healing of scratches through dynamic transesterification reaction, and the mechanical property retention rate reaches more than 94%.

[0007] CN118005908A discloses an epoxy resin-based glass polymer and its preparation method. The ester bonds formed by the ring opening of carboxylic acid groups and epoxy groups can undergo transesterification at high temperature, reorganizing the topological network and exhibiting stress relaxation macroscopically.

[0008] While quantum dot films have shown great potential in improving the color gamut of display devices, they still face two key technical challenges in practical applications and long-term reliability. First, the inherent mechanical sensitivity of quantum dot films makes them susceptible to damage. Quantum dot films themselves typically lack high mechanical strength, and are prone to creases and failure under external stress or friction after deposition. Second, the core materials of quantum dots, especially high-performance cadmium-based quantum dots, are extremely sensitive to moisture and oxygen in the environment. The intrusion of water and oxygen triggers oxidation and photochemical degradation on the quantum dot surface, leading to an irreversible decrease in photoluminescence quantum yield, manifested as fluorescence quenching, color gamut shrinkage, and a significant reduction in lifespan. Summary of the Invention

[0009] To address the problem of reduced light efficiency after quantum dot film failure, one objective of this invention is to provide a method for preparing a self-healing functional monomer. The method includes the following steps: uniformly mixing epoxy resin, a curing agent, and a catalyst, followed by a polymerization reaction to obtain the self-healing functional monomer. This self-healing functional monomer can be introduced into the network structure of the quantum dot adhesive layer through an exchange reaction.

[0010] A second objective of this invention is to provide a quantum dot adhesive that, by introducing reversible β-hydroxy ester bonds into the quantum dot adhesive, constructs a dynamically cross-linkable reversible three-dimensional network structure, endowing the quantum dot film with intrinsic self-healing properties. The raw materials for preparing the quantum dot adhesive include the following components: adhesive resin, self-healing functional monomer, photoinitiator, antioxidant, scattering particles, and quantum dots. The self-healing functional monomer, photoinitiator, antioxidant, scattering particles, and quantum dots are dispersed within the adhesive resin and stirred uniformly under inert gas protection to obtain the quantum dot adhesive.

[0011] A third objective of this invention is to provide a method for preparing a quantum dot film. The raw materials for preparing the quantum dot film include the following components: an upper barrier film, a quantum dot adhesive layer, and a lower barrier film. The method for preparing the quantum dot film includes the following steps: uniformly coating the inner surfaces of the upper and lower barrier films with quantum dot adhesive, and then subjecting the coated composite film to rapid UV curing to obtain the finished quantum dot film.

[0012] To achieve the above objectives, the present invention adopts the following technical solution:

[0013] In a first aspect, the present invention provides a self-healing functional monomer, wherein the raw materials for preparing the self-healing functional monomer include: epoxy resin, curing agent and catalyst; wherein the epoxy resin is glycidyl ether; wherein the curing agent is carboxylic anhydride, and the molar ratio of the epoxy resin, curing agent and catalyst is 1:(0.3-0.6):0.05.

[0014] The epoxy resin is any one or more of 1,2-cyclohexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,4-cyclohexanediethanol diglycidyl ether, 1,6-hexanediol diglycidyl ether, and 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexanecarbamate, preferably 1,4-cyclohexanediethanol diglycidyl ether.

[0015] The curing agent is a carboxylic anhydride curing agent, such as any one or more of methyl hexahydrophthalic anhydride, hexahydrophthalic anhydride, methyl nadic anhydride, dodecenyl succinic anhydride, phthalic anhydride, and maleic anhydride, preferably methyl hexahydrophthalic anhydride.

[0016] The catalyst is any one of benzyldimethylamine, tris(dimethylaminomethyl)phenol, 2-ethyl-4-methylimidazole, 1-cyanoethyl-2-ethyl-4-methylimidazole, zinc acetylacetone, and boron trifluoride-amine complex, preferably 1-cyanoethyl-2-ethyl-4-methylimidazole.

[0017] The raw materials for preparing the self-healing functional monomers are all commercially available, requiring no special processing and can be used directly.

[0018] The present invention also provides a method for preparing the self-healing functional monomer, comprising: mixing epoxy resin, curing agent and catalyst in a certain molar ratio under stirring conditions, heating and stirring evenly to obtain epoxy prepolymer, removing bubbles from epoxy prepolymer and drying it to obtain self-healing functional monomer.

[0019] Furthermore, the epoxy prepolymer is degassed and cured in an oven to obtain a self-healing functional monomer. The self-healing functional monomer is then ground into uniform particles and placed in a dry environment for later use.

[0020] Furthermore, the molar ratio of the epoxy resin, curing agent, and catalyst is 1:(0.3~0.6):0.05, for example, it can be 1:0.3:0.05, 1:0.35:0.05, 1:0.4:0.05, 1:0.45:0.05, 1:0.5:0.05, 1:0.55:0.05, 1:0.6:0.05, etc.

[0021] Furthermore, the stirring temperature is (60-90)℃, for example, it can be 60℃, 65℃, 70℃, 75℃, 80℃, 85℃, 90℃, etc.

[0022] Furthermore, the heating curing temperature of the epoxy prepolymer is (120-150)℃, for example, it can be 120℃, 125℃, 130℃, 135℃, 140℃, 145℃, 150℃, etc.

[0023] Furthermore, the curing time of the epoxy prepolymer is (2-5) hours, for example, it can be 2 hours, 2.5 hours, 3 hours, 3.5 hours, 4 hours, 4.5 hours, 5 hours, etc.

[0024] Furthermore, the particle size of the self-healing functional monomer is (1~10) μm, for example, it can be 1μm, 2μm, 4μm, 6μm, 8μm, 10μm, etc.

[0025] Secondly, the present invention provides a quantum dot adhesive, wherein the raw materials for preparing the quantum dot adhesive include the following components in parts by mass: 80-90 parts of adhesive resin, 0.5-5 parts of self-healing monomer, 0.2-2 parts of photoinitiator, 0.5-3 parts of antioxidant, 2-5 parts of scattering particles, and 1-4 parts of quantum dots.

[0026] The raw materials used in the preparation of the quantum dot adhesive are all commercially available, requiring no special processing and can be used directly.

[0027] Furthermore, in the raw materials for preparing the quantum dot adhesive, the content of adhesive resin is 80-90 parts, for example, it can be 80 parts, 82 parts, 84 parts, 86 parts, 88 parts, 90 parts, etc., preferably 82 parts.

[0028] Furthermore, in the raw materials for preparing the quantum dot adhesive, the content of the self-healing functional monomer is 0.5 to 5 parts, for example, it can be 0.5 parts, 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, 5 parts, etc., preferably 1.5 to 3 parts.

[0029] Furthermore, in the raw materials for preparing the quantum dot adhesive, the content of photoinitiator is 0.2 to 2 parts, for example, it can be 0.2 parts, 0.5 parts, 0.8 parts, 1 part, 1.2 parts, 1.5 parts, 2 parts, etc., preferably 0.5 to 1.5 parts.

[0030] Furthermore, in the raw materials for preparing the quantum dot adhesive, the content of antioxidant is 0.5 to 3 parts, for example, it can be 0.5 parts, 0.8 parts, 1 part, 1.2 parts, 1.5 parts, 2 parts, 2.5 parts, 3 parts, etc., preferably 1 to 2 parts.

[0031] Furthermore, in the raw materials for preparing the quantum dot adhesive, the content of scattering particles is 2 to 5 parts, for example, it can be 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, 5 parts, etc., preferably 3 to 4 parts.

[0032] Furthermore, in the raw materials for preparing the quantum dot adhesive, the content of quantum dots is 1 to 4 parts, for example, it can be 1 part, 1.5 parts, 2 parts, 2.5 parts, 3 parts, 3.5 parts, 4 parts, 4.5 parts, 5 parts, etc., preferably 3 parts. The content ratio of red quantum dots to green quantum dots is (1:2 to 2:1), for example, it can be 1:2, 1.2:1.8, 1.4:1.6, 1.5:1.5, 1.6:1.4, 1.8:1.2, 2:1, etc., preferably 1.4:1.6.

[0033] Furthermore, the adhesive resin is an acrylic resin system, which is a general term for polymers of acrylic acid, methacrylic acid and their derivatives.

[0034] Furthermore, the acrylic resin has excellent light transmittance, adhesion, hardness, film-forming properties, and solvent resistance. It has good compatibility with quantum dot surfaces and can be rapidly UV cured.

[0035] The photoinitiator reacts after absorbing ultraviolet light to generate active free radicals, thereby initiating a chain polymerization reaction of unsaturated double bonds in the acrylic resin, which in turn causes the resin to cure rapidly.

[0036] Furthermore, the photoinitiator is any one or a combination of at least two of the following: 2-hydroxy-2-methyl-1-phenyl-1-propanone, 1-hydroxy-cyclohexyl-phenyl ketone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone, and benzophenone.

[0037] The antioxidants are used to inhibit the oxidation reaction in the adhesive. Among them, hindered phenolic antioxidants interrupt the chain oxidation reaction by capturing free radicals; phosphonate antioxidants decompose the hydroperoxides generated during the oxidation process into stable non-free radical products, preventing them from decomposing into new free radicals.

[0038] Furthermore, the antioxidant is any one or a combination of at least two of the following: pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate), 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate n-octadecyl alcohol, 2,6-di-tert-butyl-p-cresol, tris(2,4-di-tert-butylphenyl) phosphite, bis(2,4-di-tert-butylphenyl) pentaerythritol diphosphite, and triphenyl phosphite.

[0039] The scattering particles can increase the utilization rate of blue light through scattering, thereby improving the brightness of the quantum dot film and enhancing the uniformity of the film surface appearance.

[0040] Furthermore, the scattering particles are any one or a combination of at least two of titanium dioxide, silicon dioxide, and organosilicon. The scattering particles have a particle size of 0.2–10 mm and can be uniformly dispersed in the quantum dot adhesive.

[0041] The quantum dots are red and green quantum dots, with cadmium selenide or indium phosphide as the core.

[0042] Furthermore, the red quantum dots can emit red light under blue light irradiation, with a particle size of 5-10 nm and a wavelength of 615-645 nm, such as 615 nm, 620 nm, 625 nm, 630 nm, 635 nm, 640 nm, 645 nm, etc.

[0043] Furthermore, the green quantum dots can emit green light under blue light irradiation, with a particle size of 2-5 nm and a wavelength of 530-555 nm, such as 530 nm, 535 nm, 540 nm, 545 nm, 550 nm, 555 nm, etc.

[0044] Furthermore, the red and green quantum dots can be combined with different wavelengths and proportions according to specific requirements such as color dots and color gamut.

[0045] The present invention also provides a method for preparing the quantum dot adhesive, comprising preparing the following raw materials: 80-90 parts of adhesive resin, 0.5-5 parts of self-healing monomer, 0.2-2 parts of photoinitiator, 0.5-3 parts of antioxidant, 2-5 parts of scattering particles, and 1-4 parts of quantum dots, and mixing the raw materials to obtain the quantum dot adhesive.

[0046] Thirdly, the present invention provides a self-healing quantum dot film, the quantum dot film comprising the following parts: an upper barrier film, a quantum dot adhesive layer, and a lower barrier film.

[0047] The upper and lower barrier films have the same structure, including a back coating layer, a substrate layer, an adhesive layer, a barrier layer, and a top coating layer.

[0048] Furthermore, the water vapor permeability of the upper and lower barrier membranes is less than 0.1 g / (㎡*24h).

[0049] Furthermore, the back coating comprises a resin matrix and transparent particles. The resin matrix is ​​any one or a combination of at least two of epoxy resin, acrylate resin, silicone resin, and polyurethane resin; the transparent particles are any one or a combination of at least two of polyacrylate, polystyrene, polypropylene, polycarbonate, methyl methacrylate-butadiene-styrene terpolymer, and styrene-acrylonitrile copolymer.

[0050] Furthermore, the thickness of the back coating is 1–10 μm, preferably 5–7 μm, and more preferably 6 μm.

[0051] Furthermore, the substrate layer is a transparent polymer, and the material is any one of polyethylene terephthalate, methyl methacrylate, polycarbonate, cellulose triacetate, cyclic olefin polymers, and polyvinyl alcohol.

[0052] Furthermore, the thickness of the substrate layer is 25–200 μm, preferably 50–75 μm, and more preferably 55 μm, 60 μm, 65 μm, or 70 μm.

[0053] Furthermore, the bonding layer comprises an adhesive, a crosslinking agent, and a chelating agent. The adhesive is any one or a combination of at least two of polyester, polyurethane, or polyacrylate; the crosslinking agent is any one or a combination of at least two of polycarbodiimide, aziridine, and methyl methacrylate; and the chelating agent is any one or a combination of at least two of boric acid, sodium borate, sodium acrylate, and titanate.

[0054] Furthermore, the thickness of the bonding layer is 1–10 μm, preferably 2–5 μm, and more preferably 3 μm or 4 μm.

[0055] Furthermore, the barrier layer is a polyvinyl alcohol and an inorganic oxide layer.

[0056] Furthermore, the thickness of the barrier layer is 2–20 μm, preferably 8–12 μm, and more preferably 9 μm or 10 μm.

[0057] Furthermore, the surface coating is any one or a combination of at least two of ethylene vinyl acetate, butyl acrylate, butadiene styrene, and vinyl styrene-butadiene.

[0058] Furthermore, the thickness of the surface coating is 1–10 μm, preferably 2–5 μm, and more preferably 3 μm or 4 μm.

[0059] The quantum dot adhesive layer is obtained by coating the inner side of the upper and lower barrier films with quantum dot adhesive and then UV curing.

[0060] Furthermore, the thickness of the quantum dot adhesive layer is 40–100 μm, preferably 50–70 μm, and more preferably 55 μm, 60 μm, or 65 μm.

[0061] This invention also provides a method for preparing the quantum dot film, comprising the following steps:

[0062] (1) Mix the back coating adhesive evenly, apply it to the outer surface of the substrate layer, and then obtain the back coating layer after UV curing.

[0063] The UV curing energy is 300–600 mJ / cm; the UV curing linear velocity is 5–20 m / min.

[0064] (2) Mix the bonding adhesive evenly, apply it to the inner surface of the substrate layer, and heat-cur it while bonding it with the barrier layer.

[0065] (3) Mix the top coat adhesive evenly, apply it to the barrier layer, and then heat-cur it to obtain the top coat.

[0066] (4) After the quantum dot adhesive is mixed and stirred under the protection of inert gas, the quantum dot adhesive is evenly coated on the inner surface (top coating) of the upper and lower barrier films, the upper and lower barrier films are bonded together, and the finished quantum dot film is obtained by UV rapid curing.

[0067] Furthermore, the method for preparing the quantum dot film includes the following steps:

[0068] (1) Mix the back coating adhesive evenly, apply it to the outer surface of the substrate layer, and then cure it with UV to obtain the back coating layer.

[0069] The UV curing energy is 300-600 mj / cm, preferably 500 mj / cm; the UV curing linear speed is 5-20 m / min, preferably 10 m / min; and the coating method is microgravure coating.

[0070] (2) Mix the bonding adhesive evenly and apply it to the inner surface of the substrate layer. Heat cure it while bonding it with the barrier layer.

[0071] The curing temperature is 70-90℃, preferably 80℃; the curing linear speed is preferably 5m / min; the coating method is slot coating; and the bonding method is roll bonding.

[0072] (3) Mix the topcoat adhesive evenly, apply it to the barrier layer, and then heat-cur it to obtain the topcoat layer.

[0073] The curing temperature is 80-100℃, preferably 85℃; the curing linear speed is preferably 8m / min; and the coating method is slot coating.

[0074] (4) After the quantum dot adhesive is mixed and stirred under the protection of inert gas, the quantum dot adhesive is evenly coated on the inner surface (top coating) of the upper and lower barrier films, the upper and lower barrier films are bonded together, and the finished quantum dot film is obtained by UV rapid curing.

[0075] The UV curing energy is 500-800 mj / cm, preferably 700 mj / cm; the UV curing linear speed is preferably 3 m / min; the coating method is slot coating; and the bonding method is roll bonding.

[0076] Fourthly, this invention provides the application of quantum dot adhesive in failed self-healing quantum dot films to restore optical properties.

[0077] The quantum dot film exhibits superior optical performance retention, with a brightness retention rate exceeding 98.6% and a color dot attenuation below 0.0005, meeting the requirements for reusability.

[0078] After aging at 85℃ for 1000 hours, the brightness of the quantum dot film decreased by less than 6%, with slight or no failure points, and it still maintained good optical performance and film appearance.

[0079] This invention provides an optical thin film in which quantum dots are dispersed in a polymer matrix with dynamic and reversible chemical bonds. When the adhesive layer is damaged under external stress, these dynamic bonds can recombine at the damaged site, achieving autonomous improvement of the failure and restoring the physical and optical properties of the adhesive layer, thereby protecting the internal quantum dots.

[0080] The main beneficial effects of this invention are as follows:

[0081] (1) On the one hand, β-hydroxy ester bonds with reversible properties are introduced into the molecular chain to establish a three-dimensional cross-linked network with dynamic configuration. When the quantum dot film is damaged, i.e., the adhesive layer produces failure creases, the movement of the molecular chain segments causes the broken ester carbonyl and hydroxyl groups to collide with each other and rearrange, thereby forming a complete network structure again. Macroscopically, the failure creases are invisible. The quantum dot film can achieve failure improvement through intrinsic self-healing, thereby restoring optical performance, which has practical value for reducing the assembly cost of backlight modules and extending their service life.

[0082] (2) On the other hand, self-healing monomers with saturated alicyclic structures and cyanoethyl groups were introduced into the structure of the quantum dot adhesive layer through molecular design. The rigid saturated alicyclic structure serves as a stable backbone unit, increasing the glass transition temperature of the adhesive layer and suppressing thermal motion; at the same time, the highly polar cyanoethyl groups optimize network stability through their electron-withdrawing effect. The self-healing monomers improve the thermal stability and anti-aging properties of the material, ensuring that it can effectively suppress quantum dot fluorescence quenching and failure under light and heat environments, thereby significantly improving its reliability. Attached Figure Description

[0083] Figure 1 Infrared spectra of quantum dot adhesive layers provided for Example 1 and Comparative Example 1.

[0084] Figure 2 The quantum dot film failure improvement diagrams provided for Example 1 and Comparative Example 1; Detailed Implementation

[0085] To better understand the structure of the present invention and the functional features and advantages it can achieve, the technical solution will be described in detail and completely below in conjunction with the preferred embodiments of the present invention.

[0086] Example 1

[0087] (1) Preparation of self-healing functional monomers

[0088] This embodiment provides a self-healing functional monomer. The preparation method of the self-healing functional monomer is as follows: under stirring conditions, epoxy resin 1,2-cyclohexanediol diglycidyl ether, curing agent methyl hexahydrophthalic anhydride, and catalyst benzyl dimethylamine are mixed at a molar ratio of 1:0.3:0.05 and stirred evenly at 60°C to obtain an epoxy prepolymer. Subsequently, the epoxy prepolymer is degassed and cured in an oven at 120°C for 5 hours to obtain the self-healing functional monomer. The self-healing functional monomer is ground into uniform particles with a particle size of 2μm and placed in a dry environment for later use.

[0089] (2) Preparation of quantum dot films

[0090] This embodiment provides a method for preparing a self-healing quantum dot film, wherein the raw materials for preparing the quantum dot adhesive include the following components in parts by mass:

[0091]

[0092] The raw materials for preparing the quantum dot film include: an upper barrier film, the quantum dot adhesive provided in Example 1, and a lower barrier film.

[0093] The method for preparing the finished quantum dot film includes the following steps:

[0094] (1) Mix the back coating adhesive evenly and apply it to the outer surface of the substrate layer using a micro-gravure coating process. After UV curing (energy of 500mj / cm, linear speed of 10m / min), the back coating layer is obtained.

[0095] (2) Mix the bonding adhesive evenly and apply it to the inner surface of the substrate layer using a slot coating process. While rolling and bonding with the barrier layer, heat curing is carried out (temperature is 80℃; line speed is 5m / min).

[0096] (3) Mix the topcoat adhesive evenly and apply it to the barrier layer using a slot coating process. After heat curing (temperature 85℃; linear speed 8m / min), the topcoat layer is obtained.

[0097] (4) After the quantum dot adhesive is mixed and stirred under the protection of inert gas, the quantum dot adhesive is evenly coated on the inner surface (top coating) of the upper and lower barrier films using a slit coating process. The upper and lower barrier films are then rolled and bonded together, and the finished quantum dot film is obtained by UV rapid curing (energy of 700mj / cm, linear speed of 3m / min).

[0098] The thickness of the quantum dot adhesive layer is 70 μm, and the thickness of the finished quantum dot film is 220 μm.

[0099] Example 2

[0100] (1) Preparation of self-healing functional monomers

[0101] This embodiment provides a self-healing functional monomer. The preparation method of the self-healing functional monomer is as follows: under stirring conditions, epoxy resin neopentyl glycol diglycidyl ether, curing agent hexahydrophthalic anhydride, and catalyst tris(dimethylaminomethyl)phenol are mixed at a molar ratio of 1:0.35:0.05 and stirred evenly at 65°C to obtain an epoxy prepolymer. Subsequently, the epoxy prepolymer is degassed and cured in an oven at 125°C for 4.5 hours to obtain the self-healing functional monomer. The self-healing functional monomer is ground into uniform particles with a particle size of 4μm and placed in a dry environment for later use.

[0102] (2) Preparation of quantum dot films

[0103] This embodiment provides a method for preparing a self-healing quantum dot film, wherein the raw materials for preparing the quantum dot adhesive include the following components in parts by mass:

[0104] Adhesive resin acrylic resin 82 copies Photoinitiator 1-Hydroxy-cyclohexyl-phenyl ketone 0.8 copies antioxidants 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate n-octadecyl alcohol ester 1.8 copies Scattering particles Titanium dioxide 3.2 copies quantum dots Red quantum dots 1.4 copies quantum dots Green quantum dots 1.6 copies Self-healing function unit Example 2 provides a self-healing functional unit 2.7 copies

[0105] The raw materials for preparing the quantum dot film include: an upper barrier film, the quantum dot adhesive provided in Example 2, and a lower barrier film.

[0106] The preparation method of the finished quantum dot film is the same as in Example 1.

[0107] The thickness of the quantum dot adhesive layer is 70 μm, and the thickness of the finished quantum dot film is 220 μm.

[0108] Example 3

[0109] (1) Preparation of self-healing functional monomers

[0110] This embodiment provides a self-healing functional monomer. The preparation method of the self-healing functional monomer is as follows: under stirring conditions, epoxy resin 1,4-cyclohexanediethanol diglycidyl ether, curing agent methylhexahydrophthalic anhydride, and catalyst 1-cyanoethyl-2-ethyl-4-methylimidazolium are mixed in a molar ratio of 1:0.4:0.05 and stirred evenly at 70°C to obtain an epoxy prepolymer. Subsequently, the epoxy prepolymer is degassed and cured in an oven at 130°C for 4 hours to obtain the self-healing functional monomer. The self-healing functional monomer is ground into uniform particles with a particle size of 5μm and placed in a dry environment for later use.

[0111] (2) Preparation of quantum dot films

[0112] This embodiment provides a method for preparing a self-healing quantum dot film, wherein the raw materials for preparing the quantum dot adhesive include the following components in parts by mass:

[0113] Adhesive resin acrylic resin 82 copies Photoinitiator 2,4,6-Trimethylbenzoyl-diphenylphosphine oxide 1 copy antioxidants 2,6-Di-tert-butyl-p-cresol 1.6 copies Scattering particles silicon dioxide 3.4 copies quantum dots Red quantum dots 1.4 copies quantum dots Green quantum dots 1.6 copies Self-healing function unit Example 3 provides a self-healing functional unit 2.4 copies

[0114] The raw materials for preparing the quantum dot film include: an upper barrier film, the quantum dot adhesive provided in Example 3, and a lower barrier film.

[0115] The preparation method of the finished quantum dot film is the same as in Example 1.

[0116] The thickness of the quantum dot adhesive layer is 70 μm, and the thickness of the finished quantum dot film is 220 μm.

[0117] Example 4

[0118] (1) Preparation of self-healing functional monomers

[0119] This embodiment provides a self-healing functional monomer. The preparation method of the self-healing functional monomer is as follows: Under stirring conditions, epoxy resin 1,4-cyclohexanediethanol diglycidyl ether, curing agent dodecenylsuccinic anhydride, and catalyst 1-cyanoethyl-2-ethyl-4-methylimidazolium are mixed at a molar ratio of 1:0.45:0.05 and stirred evenly at 75°C to obtain an epoxy prepolymer. Subsequently, the epoxy prepolymer is degassed and cured in an oven at 135°C for 3.5 hours to obtain the self-healing functional monomer. The self-healing functional monomer is ground into uniform particles with a particle size of 6 μm and placed in a dry environment for later use.

[0120] (2) Preparation of quantum dot films

[0121] This embodiment provides a method for preparing a self-healing quantum dot film, wherein the raw materials for preparing the quantum dot adhesive include the following components in parts by mass:

[0122] Adhesive resin acrylic resin 82 copies Photoinitiator Bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide 1.2 portions antioxidants Tris(2,4-di-tert-butylphenyl)phosphite 1.4 copies Scattering particles silicon dioxide 3.6 copies quantum dots Red quantum dots 1.4 copies quantum dots Green quantum dots 1.6 copies Self-healing function unit Example 4 provides a self-healing functional unit 2.1 copies

[0123] The raw materials for preparing the quantum dot film include: an upper barrier film, the quantum dot adhesive provided in Example 4, and a lower barrier film.

[0124] The preparation method of the finished quantum dot film is the same as in Example 1.

[0125] The thickness of the quantum dot adhesive layer is 70 μm, and the thickness of the finished quantum dot film is 220 μm.

[0126] Example 5

[0127] (1) Preparation of self-healing functional monomers

[0128] This embodiment provides a self-healing functional monomer. The preparation method of the self-healing functional monomer is as follows: Under stirring conditions, epoxy resin 1,4-cyclohexanediethanol diglycidyl ether, curing agent phthalic anhydride, and catalyst zinc acetylacetonate are mixed at a molar ratio of 1:0.5:0.05 and stirred evenly at 80°C to obtain an epoxy prepolymer. Subsequently, the epoxy prepolymer is degassed and cured in an oven at 140°C for 3 hours to obtain the self-healing functional monomer. The self-healing functional monomer is ground into uniform particles with a particle size of 8μm and placed in a dry environment for later use.

[0129] (2) Preparation of quantum dot films

[0130] This embodiment provides a method for preparing a self-healing quantum dot film, wherein the raw materials for preparing the quantum dot adhesive include the following components in parts by mass:

[0131]

[0132] The raw materials for preparing the quantum dot film include: an upper barrier film, the quantum dot adhesive provided in Example 5, and a lower barrier film.

[0133] The preparation method of the finished quantum dot film is the same as in Example 1.

[0134] The thickness of the quantum dot adhesive layer is 70 μm, and the thickness of the finished quantum dot film is 220 μm.

[0135] Example 6

[0136] (1) Preparation of self-healing functional monomers

[0137] This embodiment provides a self-healing functional monomer. The preparation method of the self-healing functional monomer is as follows: under stirring conditions, epoxy resin 1,4-cyclohexanediethanol diglycidyl ether, curing agent maleic anhydride, and catalyst 1-cyanoethyl-2-ethyl-4-methylimidazol are mixed at a molar ratio of 1:0.6:0.05 and stirred evenly at 90°C to obtain an epoxy prepolymer. Subsequently, the epoxy prepolymer is degassed and cured in an oven at 150°C for 2 hours to obtain the self-healing functional monomer. The self-healing functional monomer is ground into uniform particles with a particle size of 10 μm and placed in a dry environment for later use.

[0138] (2) Preparation of quantum dot films

[0139] This embodiment provides a method for preparing a self-healing quantum dot film, wherein the raw materials for preparing the quantum dot adhesive include the following components in parts by mass:

[0140]

[0141]

[0142] The raw materials for preparing the quantum dot film include: an upper barrier film, the quantum dot adhesive provided in Example 6, and a lower barrier film.

[0143] The preparation method of the quantum dot film is the same as in Example 1.

[0144] The thickness of the quantum dot adhesive layer is 70 μm, and the thickness of the finished quantum dot film is 220 μm.

[0145] Comparative Example 1

[0146] The preparation method of Example 1 was repeated according to the specified proportions of each component, but without adding the self-healing functional monomer.

[0147] Comparative Example 2

[0148] The preparation method of Example 2 was repeated according to the specified proportions of each component, but without adding the self-healing monomer.

[0149] Comparative Example 3

[0150] The preparation method of Example 3 was repeated according to the specified proportions of each component, but without adding the self-healing functional monomer.

[0151] Comparative Example 4

[0152] The preparation method of Example 4 was repeated according to the specified proportions of each component, but without adding the self-healing functional monomer.

[0153] The performance testing methods for the quantum dot films in the examples and comparative examples are as follows:

[0154] Test 1: Optical Test.

[0155] Test instrument: CS2000 spectroradiometer, 32-inch blue backlight.

[0156] Test samples: Finished quantum dot films provided in the examples and comparative examples.

[0157] Test method: The quantum dot film was cut into A4 size and placed in the center of a 32-inch blue backlight. Two brightness enhancement films were placed on top of the quantum dot film as the module structure. The optical performance was tested using a CS2000 spectroradiometer.

[0158] Test 2: Aging test.

[0159] Testing instruments: high temperature environmental chamber, CS2000 spectroradiometer, 32-inch blue backlight.

[0160] Test samples: Finished quantum dot films provided in the examples and comparative examples.

[0161] Test method: The quantum dot film was aged at 85℃ for 1000h, and the changes in optical properties before and after aging were compared.

[0162] Test 3: Failure Improvement Test.

[0163] Testing instruments: high temperature environmental chamber, CS2000 spectroradiometer, 32-inch blue backlight.

[0164] Test samples: Finished quantum dot films provided in the examples and comparative examples.

[0165] Test method: The quantum dot film was artificially folded and then covered with a glass slide and baked under static pressure for 3 hours at 85°C. The changes in the appearance and optical properties of the film before and after baking were compared.

[0166] Test 4: Infrared test.

[0167] Test instrument: FTIR Invenio R Fourier transform infrared spectrometer.

[0168] Test samples: Finished quantum dot films provided in the examples and comparative examples.

[0169] Test method: Remove the top and bottom barrier layers of the finished quantum dot film and test the quantum dot adhesive layer using the ATR method.

[0170] The structures of the quantum dot adhesive layers provided in Example 1 and Comparative Example 1 were characterized by infrared spectroscopy, and the spectra are shown below. Figure 1 As shown. Compared to the spectrum of Comparative Example 1, the spectrum of Example 1 at 3500 cm⁻¹... -1 The peak at 1720 cm⁻¹ exhibits a distinct characteristic peak of free hydroxyl (OH) groups. -1A stronger characteristic peak of ester carbonyl (C=O) was observed at this location. The above analysis indicates that the ester carbonyl and hydroxyl groups in the self-healing monomers are introduced into the cross-linking network of the quantum dot adhesive layer.

[0171] Table 1 shows a comparison of failure improvement test data between the examples and the comparative examples.

[0172]

[0173] The failure improvement test data for the examples and comparative examples are shown in Table 1. After being intentionally damaged, the quantum dot films experienced a brightness loss of 37.1%–43.8%. After static pressure baking at 85°C for 3 hours, the quantum dot films provided in Comparative Examples 1–4 showed no improvement in failure and could not be used further. The quantum dot films provided in Examples 1–6 exhibited superior optical performance retention, with a brightness retention rate higher than 98.6% and a color point attenuation lower than 0.0005, meeting the requirements for reusability. Figure 2 As shown, the quantum dot film provided in Example 1, after baking, showed effective improvement in failure creases, which became invisible under blue light conditions; the quantum dot film provided in Comparative Example 1 still showed clearly visible creases, resulting in a poor film appearance. Under thermal stimulation, the molecular network reorganized through dynamic ester exchange, macroscopically manifested as the healing of the adhesive layer damage, and the optical properties at that location were restored.

[0174] Table 2 shows a comparison of aging test data between the examples and the comparative examples.

[0175]

[0176] The aging test data for the examples and comparative examples are shown in Table 2. After aging at 85°C for 1000 hours, the quantum dot films provided in Comparative Examples 1-4 showed a brightness decrease of over 12%, with obvious failure points appearing on the film surface. In contrast, the quantum dot films provided in Examples 1-6 showed a brightness decrease of less than 6%, with slight or no failure points, maintaining good optical performance and film appearance. The introduction of self-healing monomers containing highly stable structures (saturated alicyclic structures and cyanoethyl groups) effectively improved the aging resistance of the quantum dot films, thereby enhancing the reliability of the backlight module.

[0177] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structure made using the contents of the present invention specification and drawings, or directly or indirectly applied to other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A self-healing functional monomer, wherein the raw materials for preparing the self-healing functional monomer include: Epoxy resin, curing agent, and catalyst; The epoxy resin is glycidyl ether; The curing agent is a carboxylic anhydride, and the molar ratio of the epoxy resin, curing agent and catalyst is 1:(0.3~0.6):0.

05.

2. The self-healing functional unit according to claim 1, characterized in that, The epoxy resin is any one or more of 1,2-cyclohexanediol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,4-cyclohexanediethanol diglycidyl ether, 1,6-hexanediol diglycidyl ether, and 3,4-epoxycyclohexylmethyl-3',4'-epoxycyclohexanecarboxylate; the curing agent is any one or more of methylhexahydrophthalic anhydride, hexahydrophthalic anhydride, methylnadic anhydride, dodecenylsuccinic anhydride, phthalic anhydride, and maleic anhydride; the catalyst is any one of benzyl dimethylamine, tris(dimethylaminomethyl)phenol, 2-ethyl-4-methylimidazolium, 1-cyanoethyl-2-ethyl-4-methylimidazolium, zinc acetylacetonate, and boron trifluoride-amine complex.

3. A method for preparing the self-healing functional monomer of claim 1 or 2, comprising: Under stirring conditions, epoxy resin, curing agent and catalyst are mixed in a certain molar ratio, heated and stirred evenly to obtain epoxy prepolymer. The epoxy prepolymer is degassed and dried to obtain self-healing functional monomer.

4. The method for preparing the self-healing functional monomer according to claim 3, characterized in that, The stirring temperature is (60-90)℃, and the heating curing temperature of the epoxy prepolymer is (120-150)℃.

5. The method for preparing the self-healing functional monomer according to claim 3 or 4, characterized in that, The curing time of the epoxy prepolymer is (2-5) h.

6. The method for preparing the self-healing functional monomer according to claim 3 or 4, characterized in that, The particle size of the self-healing functional monomer is (1-10) μm.

7. A quantum dot adhesive, wherein the raw materials for preparing the quantum dot adhesive comprise the following components by mass parts: 80-90 parts of adhesive resin, 0.5-5 parts of the self-healing functional monomer as described in claim 1 or 2, 0.2-2 parts of photoinitiator, 0.5-3 parts of antioxidant, 2-5 parts of scattering particles, and 1-4 parts of quantum dots.

8. A quantum dot adhesive, wherein the raw materials for preparing the quantum dot adhesive comprise the following components by mass parts: 80-90 parts of adhesive resin, 0.5-5 parts of self-healing functional monomer prepared by the preparation method of any one of claims 3 to 6, 0.2-2 parts of photoinitiator, 0.5-3 parts of antioxidant, 2-5 parts of scattering particles, and 1-4 parts of quantum dots.

9. The quantum dot adhesive according to claim 7 or 8, characterized in that, The adhesive resin is an acrylic resin, and the photoinitiator is any one or a combination of at least two of the following: 2-hydroxy-2-methyl-1-phenyl-1-propanone, 1-hydroxy-cyclohexyl-phenyl ketone, 2,4,6-trimethylbenzoyl-diphenylphosphine oxide, bis(2,4,6-trimethylbenzoyl)phenylphosphine oxide, 2-methyl-1-[4-(methylthio)phenyl]-2-morpholino-1-propanone, and benzophenone; the antioxidant is any one or a combination of at least two of the following: pentaerythritol tetrakis(3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate), octadecyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate, 2,6-di-tert-butyl-p-cresol, tris(2,4-di-tert-butylphenyl) phosphite, bis(2,4-di-tert-butylphenyl)pentaerythritol diphosphite, and triphenyl phosphite.

10. A self-healing quantum dot film, the quantum dot film comprising: an upper barrier film, a quantum dot adhesive layer, and a lower barrier film, wherein the quantum dot adhesive layer is formed of the quantum dot adhesive of any one of claims 7 to 9.

11. A method for preparing the quantum dot film of claim 10, comprising the following steps: (1) Mix the back coating adhesive evenly, apply it to the outer surface of the substrate layer, and then obtain the back coating layer after UV curing. The UV curing energy is 300–600 mJ / cm; the UV curing linear velocity is 5–20 m / min. (2) Mix the bonding adhesive evenly, apply it to the inner surface of the substrate layer, and heat-cur it while bonding it with the barrier layer. (3) Mix the top coat adhesive evenly, apply it to the barrier layer, and then heat-cur it to obtain the top coat. (4) After the quantum dot adhesive is mixed and stirred under the protection of inert gas, the quantum dot adhesive is evenly coated on the inner surface (top coating) of the upper and lower barrier films, the upper and lower barrier films are bonded together, and the finished quantum dot film is obtained by UV rapid curing.

12. The application of the quantum dot adhesive of any one of claims 7 to 9 in a failed self-healing quantum dot film to restore optical properties; The quantum dot film exhibits superior optical performance retention, with a brightness retention rate exceeding 98.6% and a color point attenuation below 0.0005, meeting the requirements for repeated use. After aging at 85°C for 1000 hours, the brightness attenuation of the quantum dot film is less than 6%, with slight or no failure points, maintaining good optical performance and film appearance.

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