Light-cured resin composition and preparation method thereof

Abstract

The invention belongs to the technical field of materials, and particularly relates to a light-cured resin composition and a preparation method thereof. The light-cured resin composition comprises light-cured resin, a surface-modified metal oxide, a photoinitiator, a solvent and an auxiliary agent. The light-cured resin composition provided by the invention integrates the performance combination of high light transmittance, high thermal stability and storage stability, after the resin is cured, pattern deformation or cracking caused by internal stress release is not easily caused, excellent pattern forming precision is shown in an application scene, and the finally formed pattern is clear in edge and small in size error.

Description

A photocurable resin composition and its preparation method Technical Field

[0001] This invention belongs to the field of materials technology, specifically relating to a photocurable resin composition and its preparation method. Background Technology

[0002] In the field of micro-nano manufacturing, optical adhesives are key materials for achieving high-precision pattern processing. They are widely used in various scenarios requiring precise pattern transfer, such as the production of semiconductor devices, display panels, and optical components. Their performance directly affects the processing accuracy, optical effect, and service life of the final product. For example, in the creation of fine patterns, the transparency, adhesion, and stability of optical adhesives affect the clarity of the pattern and its reliability in long-term use, which is an important foundation for ensuring the smooth progress of micro-nano manufacturing processes.

[0003] Currently, to meet the demands for miniaturization and high performance in optical devices, developing optical adhesives that combine high refractive index with excellent overall performance has become a technological focus. However, existing material systems, while pursuing higher refractive indices, still face a series of key technological bottlenecks. On the one hand, while simply designing organic molecules (such as introducing highly polarizable groups like sulfur and aromatic rings) can increase the refractive index, it is usually difficult to break through the upper limit of 1.8, and compatibility with processes faces challenges. On the other hand, doping inorganic nanoparticles (such as titanium dioxide) into a polymer matrix is ​​an effective way to obtain high refractive indices, reaching 1.67 or even higher. However, the uniform dispersion and long-term stability of nanoparticles, as well as the maintenance of light transmittance and control of haze under high filling amounts, are key challenges restricting their practical application. A more prominent problem is that when the refractive index is increased to 1.9 or higher to meet the requirements of AR / VR devices for a wider field of view, the material often exhibits significant degradation in light resistance, seriously affecting the reliability of optical devices operating in the visible light band for extended periods. In addition, existing high-refractive-index optical adhesives, while ensuring high optical performance, also need to take into account the stringent requirements of nanoimprinting processes on materials such as low viscosity, rapid curing, low curing shrinkage, and good pattern transfer fidelity. How to achieve a balance and synergistic optimization of these properties is a core technical problem that urgently needs to be solved in this field. Summary of the Invention

[0004] To address the shortcomings of existing technologies, this invention provides a photocurable resin composition and its preparation method. The metal oxide in the photocurable resin composition provided by this invention effectively inhibits the catalytic activity of titanium oxide, endowing it with characteristics of high refractive index, high stability, and storage stability in photocuring applications. When combined with photocurable resins, especially those containing copolymer components, it is less prone to reactive crosslinking leading to volume shrinkage during curing, or metal oxide agglomeration causing pattern deformation or cracking. In application scenarios, it exhibits excellent pattern forming accuracy, resulting in patterns with clear edges, small dimensional errors, and excellent film uniformity and optical stability.

[0005] The technical solution provided by this invention is as follows: a photocurable resin composition comprising a photocurable resin, a surface-modified metal oxide, a photoinitiator, a solvent, and an additive; the photocurable resin is selected from: a composition consisting of at least two monomers selected from (meth)acrylate monomers containing aromatic hydrocarbons, (meth)acrylate monomers having substituted or unsubstituted alkyl groups, and (meth)acrylate monomers having substituted or unsubstituted alkyl ether groups, or a copolymer composed of the above at least two monomers, or a mixture of a copolymer composed of the above at least two monomers and at least one monomer; the surface-modified metal oxide is obtained by modifying nano-titanium oxide with a zirconate coupling agent.

[0006] It should be noted that the photocurable resin may be selected from a composition or copolymer formed of at least two monomers of (meth)acrylate monomers containing aromatic hydrocarbons, or a composition or copolymer formed of at least two monomers of (meth)acrylate monomers having substituted or unsubstituted alkyl groups, or a composition or copolymer formed of at least two monomers of (meth)acrylate monomers having substituted or unsubstituted alkyl ether groups, or a composition or copolymer formed of (meth)acrylate monomers containing aromatic hydrocarbons and (meth)acrylate monomers having substituted or unsubstituted alkyl groups, or a composition or copolymer formed of (meth)acrylate monomers containing aromatic hydrocarbons and (meth)acrylate monomers having substituted or unsubstituted alkyl ether groups, or a composition or copolymer formed of (meth)acrylate monomers having substituted or unsubstituted alkyl groups and (meth)acrylate monomers having substituted or unsubstituted alkyl ether groups.

[0007] Furthermore, the (meth)acrylic acid refers to acrylic acid and / or methacrylic acid.

[0008] Furthermore, the number of polymerizable functional groups in the aforementioned (meth)acrylate monomers containing aromatic hydrocarbons, (meth)acrylate monomers having substituted or unsubstituted alkyl groups, and (meth)acrylate monomers having substituted or unsubstituted alkyl ether groups is not particularly limited. For example, (meth)acrylate monomers containing aromatic hydrocarbons may include mono(meth)acrylate monomers containing aromatic hydrocarbons, bis(meth)acrylate monomers containing aromatic hydrocarbons, and poly(meth)acrylate monomers containing aromatic hydrocarbons. (meth)acrylate monomers having unsubstituted alkyl groups and (meth)acrylate monomers having unsubstituted alkyl ether groups may include monofunctional (meth)acrylate alkyl ester monomers, difunctional (meth)acrylate alkyl ester monomers, and polyfunctional (meth)acrylate alkyl ester monomers.

[0009] Furthermore, in (meth)acrylate monomers having substituted alkyl groups or (meth)acrylate monomers having substituted alkyl ether groups, the substituents are reactive groups selected from one of epoxy, carboxyl, hydroxyl, and amino groups.

[0010] Further examples of the epoxy-substituted alkyl group (meth)acrylate monomer and the epoxy-substituted alkyl ether group (meth)acrylate monomer include glycidyl methacrylate, glycidyl methacrylate (glycidoxy)ethyl methacrylate, and 4-(ethylene oxide-2-ylmethoxy)(meth)acrylate butyl acrylate.

[0011] Further examples of the carboxyl-substituted alkylene group of (meth)acrylate monomers include (meth)acrylic acid, 2-carboxyethyl (meth)acrylate, and 4-(6-((meth)acryloyloxy)hexyloxy)benzoic acid.

[0012] Furthermore, the alkyl group and alkyl ether group have 1-20 carbon atoms; the aromatic hydrocarbon has a structural unit having 1-4 phenyl groups.

[0013] Furthermore, the structural unit having 1-4 phenyl groups includes benzene, biphenyl, naphthalene, diphenylmethane, diphenyl ether, fluorene, and 9,9-diphenylfluorene.

[0014] Furthermore, the poly(meth)acrylate monomer containing aromatic hydrocarbons is a C-type structure with 1-4 phenyl units substituted by single bonds, hydroxyl groups, or unsubstituted. 1-20 Alkyl, hydroxyl-substituted or unsubstituted C 1-20 alkyl ether group, hydroxyl group or unsubstituted C 1-20 Mono(meth)acrylate monomers or bis(meth)acrylate monomers formed by bonding any one of the alkyl ester groups to a (meth)acrylate functional group.

[0015] Examples of the poly(meth)acrylate monomers containing aromatic hydrocarbons include benzyl (meth)acrylate, 3-phenylpropyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, 3-phenoxybenzyl acrylate, 2-(meth)acrylate-2-hydroxy-3-phenoxypropyl acrylate, 4-biphenylmethanol (meth)acrylate, polyethylene glycol o-phenylphenyl ether (meth)acrylate, 3-phenoxybenzyl (meth)acrylate, and 2-[4-(1-methyl-]acrylate. 1-Phenylacetyl)phenoxy]ethyl ester, 2-(meth)acryloyloxy-2-hydroxypropyl phthalate, 2-[4-(1-methyl-1-phenoxy]ethyl acrylate, isophthalamide di(meth)acrylate, isophthalamide dimethacrylate, 4,4'-biphenyl diisobutylene acrylate, bisphenol α di(meth)acrylate, bisphenol α polyethylene glycol diether di(meth)acrylate, diether fluorene acrylate, 2-(2-naphthoxy)-(meth)acrylate ethyl ester.

[0016] The photocurable resin comprises at least a (meth)acrylate monomer containing an aromatic hydrocarbon group, or a copolymer comprising at least a (meth)acrylate monomer containing an aromatic hydrocarbon group; the copolymer is obtained by copolymerizing at least one (meth)acrylate monomer containing an aromatic hydrocarbon group with at least one monomer selected from alkyl (meth)acrylate with an epoxy group substituted with an epoxy group and alkyl ether (meth)acrylate with an epoxy group substituted with an epoxy group, and then subjecting it to a secondary polymerization with one monomer selected from alkyl (meth)acrylate with a carboxyl group substituted with an alkyl group substituted with a carboxyl group and alkyl ether (meth)acrylate with a carboxyl group substituted with an alkyl group substituted with a carboxyl group; the copolymer contains structural units with hydroxyl side chains.

[0017] Examples of alkyl chains with 1-20 carbon atoms in (meth)acrylate monomers having unsubstituted alkyl groups or (meth)acrylate monomers having unsubstituted alkyl ether groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, dibutyl, tert-butyl, fluorenyl, hexyl, heptyl, octyl, and nonyl.

[0018] Examples of (meth)acrylate monomers having unsubstituted alkyl groups and (meth)acrylate monomers having unsubstituted alkyl ether groups include: methyl (meth)acrylate, n-amyl (meth)acrylate, isobutyl (meth)acrylate, isoamyl (meth)acrylate, hexyl (meth)acrylate, isooctyl (meth)acrylate, 1,6-hexanediol di(meth)acrylate, ethylene glycol dimethacrylate, 1-hydroxy-1,2-ethylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, etc. Acrylic esters, 1,6-hexanediol di(meth)acrylate, tripropylene glycol di(meth)acrylate, 1,12-dodecanediol di(meth)acrylate, trimethylolethane tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, ethoxylated pentaerythritol tetra(meth)acrylate, polydipentaerythritol penta(meth)acrylate, polydipentaerythritol hexa(meth)acrylate, ethoxylated trimethylolpropane tri(meth)acrylate, ethoxylated glycerol tri(meth)acrylate, etc.

[0019] The zirconate coupling agent is centered on a zirconium atom and has at least one saturated or unsaturated alkoxy hydrolysate group and other organic groups; the organic group is selected from amino, hydroxyl, and mercapto groups bonded to the central zirconium atom via single bonds, N atoms, O atoms, ester bonds, acyl groups, sulfonate bonds, phosphate ester bonds, pyrophosphate ester bonds, sulfonic acid acyloxy groups, or sulfonic acid acyloxy groups, and is either substituted or unsubstituted C groups. 1-20 Saturated or unsaturated alkyl groups, or C atoms bonded to the central zirconium atom via single bonds, N atoms, O atoms, ester bonds, acyl groups, sulfonate bonds, phosphate ester bonds, pyrophosphate ester bonds, sulfonyloxy groups, or sulfonyloxy groups. 1-20 The alkyl, amino, hydroxyl, thiol-substituted or unsubstituted phenyl group.

[0020] Furthermore, the zirconate coupling agent has 1-2 saturated or unsaturated alkoxy hydrolyzable groups and 2-3 other organic groups.

[0021] Furthermore, the hydrolyzable group is preferably C. 1-6 Alkyl groups. Alkyl groups can form strong chemical bonds (Zr-O-metal atoms) on the surface of metal oxides after hydrolysis. In particular, high-refractive-index nano-titanium dioxide particles have photocatalytic activity. When a dense coating layer is formed on their surface by a zirconate coupling agent, the nano-titanium dioxide particles have a high refractive index while reducing their absorption of ultraviolet light during photocuring.

[0022] When other organic groups in the zirconate coupling agent coat titanium oxide with strongly polar groups such as N atoms, O atoms, ester bonds, acyl groups, sulfonate bonds, phosphate ester bonds, pyrophosphate ester bonds, sulfonic acid acyloxy groups, etc., they can further form strong anchoring ends and stably bind to the surface of titanium oxide, and capture electron-hole pairs, ensuring that the alkyl chains coated on the surface will not fall off the surface of titanium oxide even under harsh environments, further consolidating the interfacial connection and the stability of titanium dioxide nanoparticles.

[0023] Furthermore, the surface-modified metal oxide is obtained through the following steps: dispersing nano-titanium oxide particles in a solvent to prepare a nano-titanium dioxide particle dispersion, adjusting the nano-titanium dioxide particle dispersion to acidic or neutral conditions, adding a zirconate coupling agent dropwise to the nano-titanium dioxide particle dispersion, stirring the reaction, and vacuum drying to obtain modified nano-titanium oxide particles; the amount of zirconate coupling agent added is 1%-20% of the mass of the nano-titanium oxide.

[0024] As the most preferred option, the nano-titanium oxide is nano-titanium dioxide.

[0025] Preferably, the nanoparticle size range is 10nm-50nm.

[0026] Furthermore, the photoinitiator is selected from any one or more combinations of α-hydroxy ketone initiators, benzoin initiators, acylphosphine oxide initiators, acetophenone initiators, morpholino ketone initiators, and oxime ester photoinitiators.

[0027] In this invention, the functional additives include any one or a combination of at least two of the following: adhesion promoters, dispersants, surfactants, defoamers, stabilizers, and crosslinking agents.

[0028] Furthermore, the surfactant is selected from at least one of polyether-modified polydimethylsiloxane, polyester-modified polydimethylsiloxane containing polyacrylate functional groups, hydroxyl-containing polyether-modified polydimethylsiloxane, and acryloyloxy-modified silane polymers.

[0029] Furthermore, the solvent is selected from one or a mixture of esters, alcohols, ethers, ketones, benzenes. The ester solvents are selected from one or more of the following: ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol mono-n-butyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether acetate, propylene glycol monopropyl ether acetate, propylene glycol monobutyl ether acetate, methoxybutyl acetate, 3-methoxybutyl acetate, methoxypentyl acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol mono-n-butyl ether acetate, dipropylene glycol monomethyl ether acetate, triethylene glycol monomethyl ether acetate, triethylene glycol monoethyl ether acetate, 3-methyl-3-methoxybutyl acetate, ethylene glycol diacetate, 1,3-butanediol diacetate, 1,6-hexanol diacetate, and cyclohexanol acetate; the alcohols are selected from one or more of the following: methanol, ethanol, cyclohexanol, ethylene glycol, propylene glycol, butanediol, diethylene glycol, dipropylene glycol, and triethylene glycol. One or more of the following: ethers are selected from: ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol mono-n-butyl ether, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol mono-n-butyl ether, dipropylene glycol monoethyl ether, dipropylene glycol monomethyl ether, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, diethylene glycol dimethyl ether, diethylene glycol diethyl ether, diethylene glycol dipropyl ether, diethylene glycol dibutyl ether; ketones are selected from: acetone, methyl amyl ketone, methyl isopropyl ketone, methyl isoamyl ketone, diisopropyl ketone, diisobutyl ketone, methyl isobutyl ketone, cyclohexanone, ethyl amyl ketone, methyl butyl ketone, methyl hexyl ketone; benzenes are selected from: toluene, xylene, or any combination of two or more of these.

[0030] The preparation method of the photocurable resin composition is as follows: the photocurable resin, surface-modified metal oxide, photoinitiator, solvent and functional additives are mixed and put into a reaction vessel and stirred. The temperature is controlled between 25℃ and 35℃ and the stirring time is 3-5h to obtain the photocurable resin composition.

[0031] As an embodiment of this application, relative to 100 parts by weight of the photocurable resin composition, the photocurable resin is preferably 5-30 parts by weight, the surface-modified metal oxide is preferably 5-30 parts by weight, the photoinitiator is preferably 0.1-5 parts by weight, the solvent is preferably 40-80 parts by weight, and the functional additive is preferably 0-5 parts by weight.

[0032] When the photocurable resin is selected from copolymers, the following steps are also included: copolymerizing at least one monomer selected from (meth)acrylate monomers containing aromatic hydrocarbons, (meth)acrylates with epoxy-substituted alkyl groups, and (meth)acrylates with epoxy-substituted alkyl ether groups, along with a solvent and a polymerization initiator, in an oil bath at 50-110°C under nitrogen atmosphere for 2-6 hours, preferably 4 hours; after copolymerization, adding one monomer selected from (meth)acrylates with carboxyl-substituted alkyl groups and (meth)acrylates with carboxyl-substituted alkyl ether groups, along with a catalyst and a polymerization inhibitor, in an oil bath at 50-110°C under nitrogen atmosphere for 2-6 hours, preferably 4 hours, to obtain a copolymer with structural units having hydroxyl side chains.

[0033] As an example of the polymerization initiator in this application, in the preparation process of the photocurable resin as a copolymer, the initiator is a thermal polymerization initiator, which can be selected from azo thermal polymerization initiators and peroxide thermal polymerization initiators, such as azobisisobutyronitrile, benzoyl peroxide, and azobisisoheptanenitrile.

[0034] The catalyst is a phase transfer catalyst, specifically such as tetrabutylammonium bromide, tetrabutylammonium chloride, tetrabutylammonium hydrogen sulfate, triethylamine, and 18-crown-6; the polymerization inhibitor is selected from hydroxyanisole, 2-tert-butylhydroquinone, or hydroquinone.

[0035] As a preferred embodiment of this application, the photocurable resin is selected from at least one monomer among the following: (meth)acrylate monomers containing aromatic hydrocarbons, (meth)acrylates having epoxy-substituted alkyl groups, and (meth)acrylates having epoxy-substituted alkyl ether groups; and (meth)acrylates having carboxyl-substituted alkyl groups and (meth)acrylates having carboxyl-substituted alkyl ether groups, with the respective weight ratio being (20-40):(1-3):(1-3).

[0036] As an application of the photocurable resin composition of the present invention, it is used as a nanoimprint adhesive, encapsulating adhesive or high-refractive-index ink material in OLED, LCD, Micro LED, Mini LED, and AR / VR.

[0037] The surface-modified metal oxide provided by this invention, after surface modification, can form a dense cross-linked network structure with the resin matrix in a photocurable resin system. This structure can spatially restrict the free movement of nanoparticles, effectively suppressing not only the migration, aggregation, and sedimentation of nanoparticles during storage, but also inhibiting the optical activity of high-refractive-index titanium dioxide nanoparticles. This ensures that the photocurable resin maintains excellent dispersion uniformity and guarantees the long-term stability of its optical properties (such as transmittance and refractive index).

[0038] The photocurable resin composition selected in this invention introduces rigid, highly conjugated groups through aryl-containing (meth)acrylate monomers. This not only imparts a high refractive index to the material but also enhances molecular polarity through the conjugation effect, significantly improving the transmittance to over 95% in optical coatings. Furthermore, by reacting the acrylate monomers to form a prepolymer and adding it to the composite material, the UV curing activity of the acrylate groups is preserved. Simultaneously, after the monomers polymerize to form the prepolymer, the content of free acrylate monomers in the molecular structure is significantly reduced, and unsaturated double bonds are transformed into large, photocurable structural units through polymerization. This greatly reduces the amount of acrylate monomers and unsaturated double bonds in the photocurable composite, resulting in a smoother cross-linking shrinkage of the molecular chains during curing. It also effectively suppresses the volatilization loss of acrylate monomers under high-temperature conditions, ultimately significantly reducing the volume shrinkage rate of the cured resin and effectively avoiding problems such as pattern distortion caused by volume shrinkage. Meanwhile, the prepolymer has a larger molecular weight and a higher density of entanglement and cross-linking between molecular chains, which significantly increases the glass transition temperature (Tg) of the resin, further enhancing the thermal stability of the resin, reducing film thickness loss caused by thermal decomposition and thermal softening, ensuring the stability of high aspect ratio (>7:1) and film thickness, and facilitating the precision of film patterning. Detailed Implementation

[0039] The principles and features of the present invention are described below. The embodiments given are only for explaining the present invention and are not intended to limit the scope of the present invention.

[0040] Unless otherwise specified in the examples, the procedures should be performed under standard conditions or conditions recommended by the manufacturer. Reagents or instruments whose manufacturers are not specified are all commercially available products.

[0041] Example 1: S1: 21.7g of nano-titanium dioxide with a particle size of 30nm was dispersed in 20ml of chloroform, sonicated for 25min, and stirred for 25min to obtain a nano-titanium dioxide particle dispersion; hydrochloric acid was added to adjust the pH to 5, and after mixing evenly, 1g of isopropoxytris(dodecylbenzenesulfonyl)zirconate was added dropwise, and the mixture was reacted at 50℃ for 2h. After vacuum drying, modified nano-titanium dioxide particles were obtained.

[0042] S2: 6.3g benzyl acrylate, 5.8g polyethylene glycol o-phenyl phenyl ether acrylate, the above-mentioned modified nano titanium dioxide particles, 0.5g diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, 0.7g polyether-modified polydimethylsiloxane, and 65g propylene glycol methyl ether acetate were added to a reaction vessel and stirred. The mixture was stirred at 25°C for 5 hours. The mixture was then filtered through a filter with a pore size of 0.25μm to obtain the corresponding photocurable resin composition.

[0043] Example 2: S1: 21.7g of nano-titanium dioxide with a particle size of 30nm was dispersed in 20ml of chloroform, sonicated for 25min, and stirred for 25min to obtain a nano-titanium dioxide particle dispersion; hydrochloric acid was added to adjust the pH to 5, and after mixing evenly, 1g of isopropoxytris(dodecylbenzenesulfonyl)zirconate was added dropwise, and the mixture was reacted at 50℃ for 2h. After vacuum drying, modified nano-titanium dioxide particles were obtained.

[0044] S2: 5.3g benzyl acrylate, 5.8g polyethylene glycol o-phenyl phenyl ether acrylate, 1g 1-hydroxy-1,2-ethylene glycol dimethacrylate, the above-mentioned modified nano titanium dioxide particles, 0.5g diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, 0.7g polyether-modified polydimethylsiloxane, and 65g propylene glycol methyl ether acetate were added to a reaction vessel and stirred. The mixture was stirred at 25°C for 5 hours and then filtered through a filter with a pore size of 0.25μm to obtain the corresponding photocurable resin composition.

[0045] Example 3: S1: 21.7g of nano-titanium dioxide with a particle size of 30nm was dispersed in 20ml of chloroform, sonicated for 25min, and stirred for 25min to obtain a nano-titanium dioxide particle dispersion; hydrochloric acid was added to adjust the pH to 5, and after mixing evenly, 1g of isopropoxytris(dodecylbenzenesulfonyl)zirconate was added dropwise, and the mixture was reacted at 50℃ for 2h. After vacuum drying, modified nano-titanium dioxide particles were obtained.

[0046] S2: In a three-necked flask, 70 ml of propylene glycol methyl ether acetate was added, followed by 30 g of benzyl methacrylate, 1.5 g of glycidyl methacrylate, and 1.5 g of azobisisobutyronitrile. The mixture was copolymerized in a nitrogen bath at 100°C for 4 hours to obtain a copolymer grafted with terminal epoxy side chains. After cooling to room temperature, 1.5 g of acrylic acid, 0.01 g of tetrabutylammonium bromide, and 0.06 g of p-hydroxyanisole were added. The copolymer was then copolymerized in a nitrogen bath at 100°C for 4 hours, followed by a photocurable resin at 80°C and 0.1 MPa for 2 hours. The resin has a number-average molecular weight (Mn) of 2875 and a polymer molecular weight distribution index (PDI) of 1.99. S3: 6.3g of the above-mentioned photocurable resin, 5.8g of polyethylene glycol o-phenyl phenyl ether acrylate, the above-mentioned modified nano-titanium dioxide particles, 0.5g of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, 0.7g of polyether-modified polydimethylsiloxane, and 65g of propylene glycol methyl ether acetate were added to a reaction vessel and stirred. The mixture was stirred at 25°C for 5 hours and then filtered through a 0.25μm filter to obtain the corresponding photocurable resin composition.

[0047] Example 4: S1: 21.7g of nano-titanium dioxide with a particle size of 30nm was dispersed in 20ml of chloroform, sonicated for 25min, and stirred for 25min to obtain a nano-titanium dioxide particle dispersion; hydrochloric acid was added to adjust the pH to 5, and after mixing evenly, 1g of isopropoxytris(isostearoyl)zirconia ester was added dropwise, and the mixture was reacted at 50℃ for 2h. After vacuum drying, modified nano-titanium dioxide particles were obtained.

[0048] S2: In a three-necked flask, 70 ml of propylene glycol methyl ether acetate was added, followed by 30 g benzyl methacrylate, 1.5 g glycidyl methacrylate, and 1.5 g azobisisobutyronitrile. The mixture was copolymerized in a nitrogen bath at 100°C for 4 hours to obtain a copolymer grafted with terminal epoxy side chains. After cooling to room temperature, 1.5 g acrylic acid, 0.01 g tetrabutylammonium bromide, and 0.06 g p-hydroxyanisole were added. The copolymer was then copolymerized in a nitrogen bath at 100°C for 4 hours, followed by polymerization at 80°C under a negative pressure of 0.1 MPa for 2 hours to obtain the corresponding copolymer resin. The resin has a number-average molecular weight (Mn) of 2875 and a polymer molecular weight distribution index (PDI) of 1.99. S3: 6.3g of the above copolymer resin, 5.8g of polyethylene glycol o-phenyl phenyl ether acrylate, the above modified nano-titanium dioxide particles, 0.5g of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, 0.7g of polyether-modified polydimethylsiloxane, and 65g of propylene glycol methyl ether acetate were added to a reaction vessel and stirred. The mixture was stirred at 25°C for 5 hours and then filtered through a 0.25μm filter to obtain the corresponding photocurable resin composition.

[0049] Example 5: S1: 20.3g of nano-titanium dioxide with a particle size of 30nm was dispersed in 20ml of chloroform, sonicated for 25min, and stirred for 25min to obtain a nano-titanium dioxide particle dispersion; hydrochloric acid was added to adjust the pH to 5, and after mixing evenly, 1g of neoalkoxytris(neodecanoyl)zirconia ester was added dropwise, and the mixture was reacted at 50℃ for 2h. After vacuum drying, modified nano-titanium dioxide particles were obtained.

[0050] S2: 7g of ethyl 3-(2-naphthoxy)-methacrylate, 5.6g of bisphenol α-dimethacrylate, 1.1g of polydipentaerythritol pentaacrylate, the above-mentioned modified nano-titanium dioxide particles, 0.5g of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, 0.5g of polyether-modified polydimethylsiloxane, and 65g of propylene glycol methyl ether acetate were added to a reaction vessel and stirred. The mixture was stirred at 25°C for 5 hours and then filtered through a filter with a pore size of 0.25μm to obtain the corresponding photocurable resin composition.

[0051] Example 6: S1: 20.3g of nano-titanium dioxide with a particle size of 30nm was dispersed in 20ml of chloroform, sonicated for 25min, and stirred for 25min to obtain a nano-titanium dioxide particle dispersion; hydrochloric acid was added to adjust the pH to 5, and after mixing evenly, 1g of neoalkoxytris(dioctylpyrophosphoryloxy)zirconate was added dropwise, and the mixture was reacted at 50℃ for 2h, and then vacuum dried to obtain modified nano-titanium dioxide particles.

[0052] S2: 7g of ethyl 3-(2-naphthoxy)-methacrylate, 5.6g of bisphenol α-dimethacrylate, 1.1g of polydipentaerythritol pentaacrylate, the above-mentioned modified nano-titanium dioxide particles, 0.5g of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, 0.5g of polyether-modified polydimethylsiloxane, and 65g of propylene glycol methyl ether acetate were added to a reaction vessel and stirred. The mixture was stirred at 25°C for 5 hours and then filtered through a filter with a pore size of 0.25μm to obtain the corresponding photocurable resin composition.

[0053] Example 7: S1: 20.3g of nano-titanium dioxide with a particle size of 30nm was dispersed in 20ml of chloroform, sonicated for 25min, and stirred for 25min to obtain a nano-titanium dioxide particle dispersion; hydrochloric acid was added to adjust the pH to 5, and after mixing evenly, 1g of neoalkoxytris(dioctylpyrophosphoryloxy)zirconia ester was added dropwise, and the mixture was reacted at 50℃ for 2h. After vacuum drying, modified nano-titanium dioxide particles were obtained.

[0054] S2: In a three-necked flask, 70 ml of propylene glycol methyl ether acetate was added, followed by 30 g of ethyl 3-(2-naphthoxy)-methacrylate, 1.5 g of glycidyl methacrylate, and 1.5 g of azobisisobutyronitrile. Polymerization was carried out at 100°C in an oil bath under nitrogen atmosphere for 4 hours to obtain a copolymer with terminal epoxy side chains. After cooling to room temperature, 1.5 g of acrylic acid, 0.01 g of tetrabutylammonium bromide, and 0.06 g of p-hydroxyanisole were added. Polymerization was carried out at 100°C in an oil bath under nitrogen atmosphere for 4 hours, followed by polymerization at 80°C under a negative pressure of 0.1 MPa for 2 hours to obtain the corresponding copolymer resin with a number-average molecular weight (Mn) of 3360. The molecular weight distribution index (PDI) was 2.27. S3: 7g of the above copolymer resin, 5.6g of bisphenol α-dimethacrylate, 1.1g of polydipentaerythritol pentaacrylate, the above modified nano-titanium dioxide particles, 0.5g of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, 0.5g of polyether-modified polydimethylsiloxane, and 65g of propylene glycol methyl ether acetate were added to a reaction vessel and stirred. The mixture was stirred at 25°C for 5 hours and then filtered through a 0.25μm filter to obtain the corresponding photocurable resin composition.

[0055] Example 8: S1: 20.3g of nano-titanium dioxide with a particle size of 30nm was dispersed in 20ml of chloroform, sonicated for 25min, and stirred for 25min to obtain a nano-titanium dioxide particle dispersion; hydrochloric acid was added to adjust the pH to 5, and after mixing evenly, 1g of neoalkoxytris(methacryloyloxy)zirconate was added dropwise, and the mixture was reacted at 50℃ for 2h, and then vacuum dried to obtain modified nano-titanium dioxide particles.

[0056] S2: 5.3g of polyethylene glycol o-phenyl ether acrylate, 7.4g of benzyl methacrylate, 1g of 1-hydroxy-1,2-ethylene glycol dimethacrylate, the above-mentioned modified nano-titanium dioxide particles, 0.5g of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, 0.5g of polyether-modified polydimethylsiloxane, and 65g of propylene glycol methyl ether acetate were added to a reaction vessel and stirred. The mixture was stirred at 25°C for 5 hours and then filtered through a filter with a pore size of 0.25μm to obtain the corresponding photocurable resin composition.

[0057] Example 9: S1: 20.3g of nano-titanium dioxide with a particle size of 30nm was dispersed in 20ml of chloroform, sonicated for 25min, and stirred for 25min to obtain a nano-titanium dioxide particle dispersion; hydrochloric acid was added to adjust the pH to 5, and after mixing evenly, 1g of neoalkoxytris(dioctylpyrophosphoryloxy)zirconia ester was added dropwise, and the mixture was reacted at 50℃ for 2h. After vacuum drying, modified nano-titanium dioxide particles were obtained.

[0058] S2: In a three-necked flask, add 70 ml of propylene glycol methyl ether acetate, then add 15 g of polyethylene glycol o-phenyl ether acrylate, 15 g of benzyl methacrylate, 1.5 g of glycidyl methacrylate, and 1.5 g of azobisisobutyronitrile in sequence. Copolymerize in a nitrogen bath at 100°C for 4 h to obtain a copolymer grafted with terminal epoxy side chains. Cool to room temperature, then add 1.5 g of acrylic acid, 0.01 g of tetrabutylammonium bromide, and 0.06 g of p-hydroxyanisole. Copolymerize in a nitrogen bath at 100°C for 4 h, and then at 80°C under a negative pressure of 0.1 MPa for 2 h to obtain the corresponding copolymer resin with a number average molecular weight Mn of 4671 and a polymer molecular weight distribution index (PDI) of 2.82. S3: Add 12.7 g of the above copolymer resin and 1 g of... 1-Hydroxy-1,2-ethylene glycol dimethacrylate, the above-mentioned modified nano-titanium dioxide particles, 0.5g of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, 0.5g of polyether-modified polydimethylsiloxane, and 65g of propylene glycol methyl ether acetate were added to a reaction vessel and stirred. The mixture was stirred at 25°C for 5 hours and then filtered through a filter with a pore size of 0.25μm to obtain the corresponding photocurable resin composition.

[0059] Example 10: S1: 20.3g of nano-titanium dioxide with a particle size of 30nm was dispersed in 20ml of chloroform, sonicated for 25min, and stirred for 25min to obtain a nano-titanium dioxide particle dispersion; hydrochloric acid was added to adjust the pH to 5, and after mixing evenly, 1g of neoalkoxytris(methacryloyloxy)zirconate was added dropwise, and the mixture was reacted at 50℃ for 2h, and then vacuum dried to obtain modified nano-titanium dioxide particles.

[0060] S2: In a three-necked flask, add 70 ml of propylene glycol methyl ether acetate, then add 15 g of polyethylene glycol o-phenyl ether acrylate, 15 g of benzyl methacrylate, 1.5 g of glycidyl methacrylate, and 1.5 g of azobisisobutyronitrile (AIBN). Copolymerize in a nitrogen bath at 100°C for 4 hours to obtain a copolymer grafted with terminal epoxy side chains. Cool to room temperature, then add 1.5 g of acrylic acid, 0.01 g of tetrabutylammonium bromide, and 0.06 g of p-hydroxyanisole. Copolymerize in a nitrogen bath at 100°C for 4 hours, and then at 80°C under a negative pressure of 0.1 MPa. The corresponding copolymer resin was obtained after 2 hours, with a number-average molecular weight (Mn) of 3258 and a polymer molecular weight distribution index (PDI) of 2.16. S3: 6.3g of the above copolymer resin, 7.4g of benzyl methacrylate, the above modified nano-titanium dioxide particles, 0.5g of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, 0.5g of polyether-modified polydimethylsiloxane, and 65g of propylene glycol methyl ether acetate were added to a reaction vessel and stirred. The mixture was stirred at 25°C for 5 hours, and then filtered through a 0.25μm filter to obtain the corresponding photocurable resin composition.

[0061] Comparative Example 1: 6.3g benzyl acrylate, 5.8g polyethylene glycol o-phenyl phenyl ether acrylate, 21.7g nano-titanium dioxide particles with a particle size of 30nm, 0.5g diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, 0.7g polyether-modified polydimethylsiloxane, and 65g propylene glycol methyl ether acetate were added to a reaction vessel and stirred. The mixture was stirred at 25°C for 5 hours and then filtered through a filter with a pore size of 0.25μm to obtain the corresponding photocurable resin composition.

[0062] Comparative Example 2: S1: 21.7g of nano-titanium dioxide with a particle size of 30nm was dispersed in 20ml of chloroform, sonicated for 25min, and stirred for 25min to obtain a nano-titanium dioxide particle dispersion; hydrochloric acid was added to adjust the pH to 5, and after mixing evenly, 1g of 3-(methacryloyloxy)propyltrimethoxysilane was added dropwise, and the mixture was reacted at 50℃ for 2h. After vacuum drying, silane coupling agent modified nano-titanium dioxide particles were obtained.

[0063] S2: 6.3g benzyl acrylate, 5.8g polyethylene glycol o-phenyl phenyl ether acrylate, the above-mentioned modified nano titanium dioxide particles, 0.5g diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, 0.7g polyether-modified polydimethylsiloxane, and 65g propylene glycol methyl ether acetate were added to a reaction vessel and stirred. The mixture was stirred at 25°C for 5 hours. The mixture was then filtered through a filter with a pore size of 0.25μm to obtain the corresponding photocurable resin composition.

[0064] Comparative Example 3: S1: 5.3g of polyethylene glycol o-phenyl ether acrylate, 7.4g of benzyl methacrylate, 1g of 1-hydroxy-1,2-ethylene glycol dimethacrylate, 20.3g of 30nm nano-zirconia particles, 0.5g of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, 0.5g of polyether-modified polydimethylsiloxane, and 65g of propylene glycol methyl ether acetate were added to a reaction vessel and stirred. The mixture was stirred at 25°C for 5 hours and then filtered through a 0.25μm filter to obtain the corresponding photocurable resin composition.

[0065] Comparative Example 4: S1: 20.3g of 30nm nano-zirconia was dispersed in 20ml of chloroform, sonicated for 25min, and stirred for 25min to obtain a nano-zirconia particle dispersion; hydrochloric acid was added to adjust the pH to 5, and after mixing evenly, 1g of neoalkoxytris(dioctylpyrophosphoryloxy)zirconia ester was added dropwise, and the reaction was carried out at 50℃ for 2h. After vacuum drying, modified nano-zirconia particles were obtained.

[0066] S2: 5.3g of polyethylene glycol o-phenyl ether acrylate, 7.4g of benzyl methacrylate, 1g of 1-hydroxy-1,2-ethylene glycol dimethacrylate, the above-mentioned modified nano-zirconia particles, 0.5g of diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide, 0.5g of polyether-modified polydimethylsiloxane, and 65g of propylene glycol methyl ether acetate were added to a reaction vessel and stirred. The mixture was stirred at 25°C for 5 hours and then filtered through a filter with a pore size of 0.25μm to obtain the corresponding photocurable resin composition.

[0067] Performance testing: Spin-coating was performed on a silicon wafer, baked in an 80°C oven for 5 minutes, and then irradiated with an LED lamp at 1500 mJ / cm² in an N2 environment. 2 Curing yields a 1μm thick film.

[0068] 1. Refractive Index: The refractive index of the cured film at 589 nm, measured using an ellipsometer (RI, 300-800 nm), is denoted as n. 2. Stability: The photocurable resin composition is diluted to 0.5 mg / mL. The hydrodynamic diameter of the colloid is determined using DLS (Dynamic Light Scattering) method, and the relative standard deviation of the three particle sizes is calculated, denoted as RSD. 3. High-Temperature Film Thickness Loss: (Film thickness after initial baking - film thickness after baking at 180℃ for 30 min) / film thickness after initial baking * 100%. 4. Transmittance Test: A transparent glass is placed on a UV-Vis spectrophotometer (UV-5500) and zeroed. Spin-coating is then performed on this glass, baked in an 80℃ oven for 5 min, and then irradiated with an LED lamp at 1500 mJ / cm² in a N2 environment. 2 The film was cured to obtain a 1 μm thick film. The transmittance was measured using a UV-Vis spectrophotometer (UV-5500), and the average transmittance in the 780-380 nm range was calculated and denoted as AVG.

[0069] 5. Yellowing Stability Test: The cured film was placed in a UV aging test chamber and exposed for 48 hours under the conditions of UV wavelength 340nm, irradiance 0.76W / m², temperature 60°C, and humidity 80% RH. The color difference ΔE value of the cured film before and after aging was measured using a colorimeter. The test results are shown in Table 1 below: Table 1 As shown in the table above, the zirconate coupling agent-modified nano-titanium oxide imparts a higher refractive index to the photocurable resin. Simultaneously, the modified titanium oxide exhibits more stable optical properties and dispersibility. In the resin matrix, especially in the resin matrix after copolymerization of epoxy-containing acrylate monomers and carboxyl-containing acrylate monomers, it effectively avoids problems such as migration and sedimentation of nanoparticles in the photocurable resin composition. This ensures that the photosensitive resin maintains good uniformity in the colloidal system and exhibits excellent anti-aging (yellowing) properties after curing. Overall, the photocurable resin composition provided in this application demonstrates good storage stability, low yellowing performance, and low high-temperature film thickness loss, meeting the development direction of existing optical adhesives towards higher precision, higher efficiency, and longer service life.

[0070] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A photocurable resin composition, characterized in that, The product comprises a photocurable resin, a surface-modified metal oxide, a photoinitiator, a solvent, and functional additives; the photocurable resin is selected from: a composition of at least two monomers selected from (meth)acrylate monomers containing aromatic hydrocarbon groups, (meth)acrylate monomers having substituted or unsubstituted alkyl groups, and (meth)acrylate monomers having substituted or unsubstituted alkyl ether groups, or a copolymer of the above at least two monomers, or a mixture of a copolymer of the above at least two monomers and at least one monomer; the surface-modified metal oxide is obtained by modifying nano-titanium oxide with a zirconate coupling agent.

2. The photocurable resin composition according to claim 1, characterized in that, The substituents in the alkyl groups of the (meth)acrylate monomers with substituents and the alkyl ether groups of the (meth)acrylate monomers with substituents are reactive groups, and the reactive groups are selected from one of epoxy, carboxyl, hydroxyl, and amino groups; the number of carbon atoms in the alkyl groups or alkyl ether groups is 1-20; and the aromatic hydrocarbon groups are structural units having 1-4 phenyl groups.

3. The photocurable resin composition according to claim 2, characterized in that, The photocurable resin has at least one (meth)acrylate monomer containing an aromatic hydrocarbon group, or is a copolymer of at least one (meth)acrylate monomer containing an aromatic hydrocarbon group; the copolymer is obtained by copolymerizing at least one (meth)acrylate monomer containing an aromatic hydrocarbon group with at least one of (meth)acrylate monomers having an epoxy-substituted alkyl group or an epoxy-substituted alkyl ether group, and then further polymerizing it with one of (meth)acrylate monomers having a carboxyl-substituted alkyl group or a carboxyl-substituted alkyl ether group. The copolymer contains structural units with hydroxyl groups on their side chains.

4. The photocurable resin composition according to claim 1, characterized in that, Zirconate coupling agents are centered around a zirconium atom and have at least one saturated or unsaturated alkoxy hydrolysate group and other organic groups; said organic group is selected from amino, hydroxyl, and mercapto groups bonded to the central zirconium atom via single bonds, N atoms, O atoms, ester bonds, acyl groups, sulfonate bonds, phosphate ester bonds, pyrophosphate ester bonds, sulfonic acid acyloxy groups, or sulfonic acid acyloxy groups, and can be substituted or unsubstituted C groups. 1-20 Saturated or unsaturated alkyl groups, or C atoms bonded to the central zirconium atom via single bonds, N atoms, O atoms, ester bonds, acyl groups, sulfonate bonds, phosphate ester bonds, pyrophosphate ester bonds, sulfonyloxy groups, or sulfonyloxy groups. 1-20 The alkyl, amino, hydroxyl, thiol-substituted or unsubstituted phenyl group.

5. The photocurable resin composition according to claim 4, characterized in that, The zirconate coupling agent has 1-2 saturated or unsaturated alkoxy hydrolysate groups and 2-3 other organic groups.

6. The photocurable resin composition according to claim 1, characterized in that, The surface-modified metal oxide is obtained through the following steps: dispersing nano-titanium oxide particles in a solvent to prepare a nano-titanium dioxide particle dispersion; adjusting the nano-titanium dioxide particle dispersion to acidic or neutral conditions; adding a zirconate coupling agent dropwise to the nano-titanium dioxide particle dispersion; stirring the reaction; and vacuum drying to obtain modified nano-titanium oxide particles; the amount of zirconate coupling agent added is 1%-20% of the mass of the nano-titanium oxide.

7. The photocurable resin composition according to claim 1, characterized in that, The functional additives include any one or a combination of two or more of the following: adhesion promoters, dispersants, surfactants, defoamers, stabilizers, and crosslinking agents.

8. A method for preparing a photocurable resin composition according to any one of claims 1 to 7, characterized in that, The photocurable resin, surface-modified metal oxide, photoinitiator, solvent and functional additives are mixed and put into a reaction vessel and stirred. The temperature is controlled between 25℃ and 35℃ and the stirring time is 3-5 hours to obtain the photocurable resin composition.

9. The method for preparing a photocurable resin composition according to claim 8, characterized in that, When the photocurable resin is selected from copolymers, the following steps are also included: copolymerizing at least one of (meth)acrylate monomers containing aromatic hydrocarbons, (meth)acrylate monomers having epoxy-substituted alkyl groups, and (meth)acrylate monomers having epoxy-substituted alkyl ether groups, along with a solvent and a polymerization initiator, in an oil bath nitrogen environment at 50-110°C; then adding one of (meth)acrylate monomers having carboxyl-substituted alkyl groups and (meth)acrylate monomers having carboxyl-substituted alkyl ether groups, along with a catalyst and a polymerization inhibitor, in an oil bath nitrogen environment at 50-110°C to obtain a copolymer with structural units having hydroxyl side chains, which is used as a photocurable resin.

10. The application of a photocurable resin composition according to any one of claims 1 to 7, characterized in that, It can be used as a nanoimprint adhesive, encapsulating adhesive, or high-refractive-index ink material in OLED, LCD, Micro LED, Mini LED, AR, or VR.

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