An organic-inorganic hybrid optical resin, a preparation method and application thereof

Abstract

The embodiment of the present application relates to the technical field of optical resin forming, and specifically discloses an organic-inorganic hybrid optical resin, a preparation method and application thereof, wherein the organic-inorganic hybrid optical resin comprises the following raw materials: surface-modified core-shell structure zirconia nanoparticles, organic photosensitive monomer, hydrolyzable silane crosslinking agent and photoinitiator. Through reasonable use of various raw materials and in combination with a three-stage UV curing forming process, the embodiment of the present application can effectively reduce the haze and stress of the material, and at the same time, improve the refractive index, thereby solving the problem that the existing organic-inorganic hybrid optical resin cannot simultaneously have high refractive index, ultra-low haze and ultra-low stress when used for producing thick-section optical elements. Moreover, the preparation method provided by the embodiment of the present application adopts a three-stage UV curing forming process, which is easy to implement on the existing 405nm UV equipment and oven, is suitable for mass production of lenses and optical modules, and has a broad market prospect.

Description

Technical Field

[0001] This invention relates to the field of optical resin molding technology, specifically to an organic-inorganic hybrid optical resin, its preparation method, and its application. Background Technology

[0002] With the continuous development of technology, optical resins, as organic polymer materials synthesized to achieve specific optical properties, are widely used in the electronics, automotive, and other industries due to their high refractive index, light transmittance, and low density. Among them, organic-inorganic hybrid optical resins are created by combining organic and inorganic materials at the nanoscale using specific chemical or physical methods. This results in an optical resin material that combines the toughness of organic polymers with the high refractive index and high hardness of inorganic materials, attracting significant attention in fields such as optical lenses and optoelectronic devices.

[0003] However, the existing technical solutions described above have the following drawbacks: organic-inorganic hybrid optical resins prepared using traditional UV curing processes face significant challenges when used to produce optical components with thick cross-sections (typically >1 mm). They often cannot simultaneously possess high refractive index, ultra-low haze, and ultra-low stress, thus affecting the optical performance of the product. Therefore, developing a novel curing process capable of actively controlling nanophase separation and network structure formation during curing, thereby producing optical-grade resins that simultaneously possess high refractive index, ultra-low haze, and ultra-low stress, is a pressing technical challenge in this field. Summary of the Invention

[0004] The purpose of this invention is to provide an organic-inorganic hybrid optical resin to solve the problem mentioned in the background art that the organic-inorganic hybrid optical resin in the prior art usually cannot simultaneously have high refractive index, ultra-low haze and ultra-low stress when used to produce thick cross-section optical elements.

[0005] To achieve the above objectives, the embodiments of the present invention provide the following technical solutions:

[0006] An organic-inorganic hybrid optical resin comprises, by weight, the following raw materials: 30–45 parts of surface-modified core-shell zirconia nanoparticles, 50–65 parts of organic photosensitive monomers, 3–8 parts of hydrolyzable silane crosslinking agent, and 0.5–2 parts of photoinitiator; wherein the surface-modified core-shell zirconia nanoparticles are prepared by coating zirconia nanocrystals with silane coupling agents containing unsaturated double bonds and silane coupling agents containing high refractive index groups, respectively.

[0007] Preferably, the organic-inorganic hybrid optical resin has a haze ≤0.5%, a polarization stress ≤5nm-cm, and a refractive index gradient ≤2×10⁻⁶. -3mm -1 .

[0008] Preferably, the organic-inorganic hybrid optical resin is prepared by three-stage UV curing using surface-modified core-shell structured zirconia nanoparticles, organic photosensitive monomers, hydrolyzable silane crosslinking agents, and photoinitiators as raw materials.

[0009] Preferably, the three-stage UV curing molding includes three steps: UV pre-curing, UV flipping and strengthening, and heat curing.

[0010] Another objective of this invention is to provide a method for preparing an organic-inorganic hybrid optical resin, wherein the method specifically includes the following steps:

[0011] 1) Weigh out the surface-modified core-shell structured zirconia nanoparticles according to the proportion and add them to the organic photosensitive monomer. Disperse them evenly under light-protected conditions, then add the photoinitiator and hydrolyzable silane crosslinking agent and continue stirring until completely dissolved. After degassing, liquid photosensitive resin is obtained for later use.

[0012] 2) The liquid photosensitive resin obtained in step 1) is subjected to three-stage UV curing to obtain the organic-inorganic hybrid optical resin;

[0013] The UV pre-curing is performed by irradiation under a light intensity of 3-5 mW-cm² for 5-8 minutes, the UV flipping and strengthening is performed by irradiation under a light intensity of 15-20 mW-cm² for 20-30 minutes, and the heat curing is performed by heating at 80-100℃ for 1-2 hours.

[0014] Preferably, in the preparation method of the organic-inorganic hybrid optical resin, UV pre-curing, UV flipping strengthening, and thermal curing are all carried out under conditions where the oxygen concentration is less than 500 ppm.

[0015] Another objective of this invention is to provide an organic-inorganic hybrid optical resin prepared using the above-described three-stage UV curing molding process.

[0016] Another objective of this invention is to provide the application of the above-mentioned organic-inorganic hybrid optical resin in the preparation of optical lenses.

[0017] Compared with the prior art, the beneficial effects of the embodiments of the present invention are:

[0018] Compared with existing technologies, the organic-inorganic hybrid optical resin provided in this invention, through the rational use of surface-modified core-shell structured zirconia nanoparticles, organic photosensitive monomers, hydrolyzable silane crosslinking agents, photoinitiators, and other raw materials, and employing a three-stage UV curing process, can effectively reduce the haze and stress of the material while improving the refractive index. Compared with the traditional single-stage UV curing process, it solves the problem that existing organic-inorganic hybrid optical resins, when used to produce thick-section optical components, often cannot simultaneously possess high refractive index, ultra-low haze, and ultra-low stress. Moreover, the preparation method of the organic-inorganic hybrid optical resin provided in this invention is simple. The three-stage UV curing process achieves precise control of the nanophase separation process through low-intensity UV pre-curing, reducing haze by about 65%. The effective release of internal stress through post-heat curing reduces polarization stress by about 68%. The UV flipping reinforcement achieves uniform curing of the upper and lower surfaces of thick components, controlling the refractive index gradient within 2×10⁻⁶. -3 mm -1 The following methods are easily implemented on existing 405nm UV equipment and ovens, suitable for mass production of lenses and optical modules, and have broad market prospects. Attached Figure Description

[0019] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention.

[0020] Figure 1 This is a flowchart of a three-stage UV curing process provided in an embodiment of the present invention.

[0021] Figure 2 This is a schematic diagram showing the nanophase stability (DLS online monitoring) results during the curing process of a three-stage UV curing process provided in an embodiment of the present invention.

[0022] Figure 3 The graph shows the refractive index gradient measurement results of an organic-inorganic hybrid optical resin according to an embodiment of the present invention.

[0023] Figure 4 A comparison chart of haze and polarization stress test results between an organic-inorganic hybrid optical resin and a control group provided in an embodiment of the present invention. Detailed Implementation

[0024] To make the technical problems, technical solutions, and beneficial effects of this invention clearer, the technical solutions in the embodiments of this invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the following embodiments will help those skilled in the art to further understand the embodiments of this invention, but do not limit the embodiments of this invention in any way. It should be noted that those skilled in the art can make several modifications and improvements without departing from the concept of the embodiments of this invention. These all fall within the protection scope of the embodiments of this invention.

[0025] The specific implementation of the present invention will be described in detail below with reference to specific embodiments.

[0026] First, it should be noted that organic-inorganic hybrid optical resins (such as ORMOSIL) are typically produced by combining organic and inorganic materials at the nanoscale through specific chemical or physical methods. This results in an optical resin material that combines the toughness of organic polymers with the high refractive index and high hardness of inorganic materials, attracting significant attention in fields such as optical lenses and optoelectronic devices. The preparation of organic-inorganic hybrid optical resins usually involves two main steps: first, the preparation of inorganic nanoparticles, which can be achieved through various methods such as sol-gel and precipitation; second, the combination of inorganic nanoparticles and organic resin, a process that requires ensuring compatibility and dispersibility between the two. However, when preparing thick-section (typically >1 mm) optical elements, traditional UV curing processes face the following significant challenges: 1) Scattering and haze issues: During curing, the polymerization rates of the organic phase (such as acrylate) and the inorganic phase (such as nano-ZrO2 particles) are mismatched, easily leading to nanoparticle aggregation and the formation of micron-sized scattering centers, resulting in excessive haze and reduced transparency in the final product. 2) Stress and deformation issues: Traditional single-batch high-intensity UV curing can lead to excessively rapid volume shrinkage, accumulating huge internal stresses within the material, causing product warping, cracking, or significant stress birefringence, affecting optical performance. 3) Uneven curing issues: For thick-section samples, due to the limited light penetration depth, the curing degree of the upper and lower surfaces of the sample differs greatly, resulting in an excessively large refractive index gradient, affecting imaging quality.

[0027] Secondly, it should be noted that existing technologies typically employ simple single-stage UV curing, which struggles to address the aforementioned issues synergistically. The resulting organic-inorganic hybrid optical resins often fail to simultaneously possess high refractive index, ultra-low haze, and ultra-low stress, thus affecting the product's optical performance. In conclusion, developing a novel curing process capable of actively controlling nanophase separation and network structure formation during curing is a pressing technical challenge in this field.

[0028] Therefore, to address the problem that existing organic-inorganic hybrid optical resins, when used to produce thick-section optical elements, typically cannot simultaneously possess high refractive index, ultra-low haze, and ultra-low stress, this invention provides an organic-inorganic hybrid optical resin, specifically an organic-inorganic nano-hybrid optical resin obtained using a three-stage UV curing method. This organic-inorganic hybrid optical resin comprises the following raw materials: surface-modified core-shell structured zirconia nanoparticles, an organic photosensitive monomer, a hydrolyzable silane crosslinking agent, and a photoinitiator; wherein the surface-modified core-shell structured zirconia nanoparticles are prepared by coating zirconia nanocrystals with silane coupling agents containing unsaturated double bonds and silane coupling agents containing high refractive index groups, respectively.

[0029] Preferably, the organic-inorganic hybrid optical resin has a haze ≤0.5%, a polarization stress ≤5 nm-cm, and a refractive index gradient ≤2×10⁻⁶. -3 mm -1 The refractive index and Abbe number have met the design targets.

[0030] As another preferred embodiment of the present invention, the organic-inorganic hybrid optical resin comprises the following raw materials by weight: 30-45 parts of surface-modified core-shell structured zirconia nanoparticles, 50-65 parts of organic photosensitive monomer, 3-8 parts of hydrolyzable silane crosslinking agent, and 0.5-2 parts of photoinitiator; wherein, the surface-modified core-shell structured zirconia nanoparticles are prepared by coating zirconia nanocrystals with silane coupling agents containing unsaturated double bonds and silane coupling agents containing high refractive index groups, respectively.

[0031] In another preferred embodiment of the present invention, the organic-inorganic hybrid optical resin is prepared by three-stage UV curing using surface-modified core-shell structured zirconia nanoparticles, organic photosensitive monomers, hydrolyzable silane crosslinking agents, and photoinitiators as raw materials.

[0032] Specifically, the organic-inorganic hybrid optical resin is prepared by adding surface-modified core-shell structured zirconia nanoparticles to an organic photosensitive monomer, dispersing them uniformly under light-protected conditions, adding a photoinitiator, and continuing stirring until completely dissolved. After degassing, a liquid photosensitive resin is obtained and then subjected to a three-stage UV curing process. This three-stage UV curing process allows the organic network, silicon-oxygen network, and nanoparticle interface to develop simultaneously, resulting in low scattering and high dimensional stability.

[0033] In another preferred embodiment of the present invention, the three-stage UV curing molding includes three steps: UV pre-curing, UV flipping and strengthening, and post-heat curing. Specifically, through these three steps, the resulting 2mm thick sample exhibits a haze ≤0.5%, polarization stress ≤5nm-cm, and a refractive index gradient |dn-dz| ≤2×10⁻⁶. -3 mm -1 The process includes: 1) UV pre-curing (low light intensity) to release volatiles and solvents and complete the initial network; 2) UV re-curing (medium to high light intensity) to complete the main acrylic network; 3) post-heat curing (80–100℃) to promote silicone polycondensation and stress relaxation; 4) stepwise distribution of light intensity and time, with re-curing as necessary.

[0034] In another preferred embodiment of the present invention, the UV pre-curing is performed by irradiation at a light intensity of 3–5 mW-cm² for 5–8 min, the UV flipping strengthening is performed by irradiation at a light intensity of 15–20 mW-cm² for 20–30 min, and the heat curing is performed by heating at 80–100°C for 1–2 h, all under conditions of O2 concentration <500 ppm.

[0035] Preferably, the UV pre-curing conditions are: 395–405 nm, 3–5 mW-cm², 5–8 min. The UV flipping strengthening conditions are: 395–405 nm, 15–20 mW-cm², 20–30 min. The heat curing conditions are: 80–100 °C, 1–2 h, all under O₂ concentration < 500 ppm. DLS online monitoring confirmed no particle size increase (PDI remained < 0.1), and the refractive index gradient |dn-dz| was controlled ≤ 2 × 10⁻⁶. -3 mm -1 .

[0036] As another preferred embodiment of the present invention, the liquid photosensitive resin is referred to as RouteC composition, specifically a pale yellow transparent liquid, wherein surface-modified ZrO2 nanoparticles (total solid content of about 35wt%) are stably dispersed in the photosensitive acrylate matrix, and can be directly used in the subsequent three-stage UV curing molding process.

[0037] In another preferred embodiment of the present invention, the organic photosensitive monomer is a mixture of a pre-mixed, homogeneous multifunctional acrylate monomer and a reactive diluent to adjust the viscosity and refractive index (n≈1.68) of the final resin.

[0038] The multifunctional acrylate monomer is selected as a high-refractive-index main monomer (30-50 parts) containing benzene rings, sulfur atoms, or heterocyclic structures, such as bis(4-(2-acryloyloxyethylthio)phenyl) sulfide (S-DA) or trifunctional aromatic epoxy acrylate. The purpose is to provide a high refractive index >1.65 as the main component of the resin. The reactive diluent (5-15 parts) is selected as a low-viscosity, highly reactive aliphatic or alicyclic acrylate, such as isobornyl acrylate (IBOA) or dicyclopentadienyldimethyl diacrylate (DCPDA). The purpose is to adjust the viscosity of the entire system, facilitating processing and molding; its rigid structure also helps maintain the hardness and dimensional stability of the material.

[0039] Preferably, the organic photosensitive monomer is a pre-mixed, uniformly blended mixture of high-refractive-index aromatic acrylate and low-viscosity aliphatic acrylate to adjust the viscosity and refractive index (n≈1.68) of the final resin.

[0040] In another preferred embodiment of the present invention, the specific raw material of the hydrolyzable silane crosslinking agent can be tetraethoxysilane (TEOS) or methyltriethoxysilane (MTEOS). The purpose is to serve as a precursor for the inorganic network, typically added before or after the photoinitiator. During the post-thermal curing stage, they undergo hydrolysis and condensation reactions, generating an inorganic glass network composed of -Si-O-Si- structures "in situ" within the organic network, significantly improving the material's hardness, scratch resistance, and thermal stability.

[0041] In another preferred embodiment of the present invention, the photoinitiator is specifically a composite initiator system, such as a mixture of acylphosphide oxide initiators (e.g., TPO, initiator Irgacure 819) and - or α-hydroxy ketone initiators (e.g., initiator 184, initiator 1173). They are typically mixed in equal weights. This composite photoinitiator system can absorb a wider range of ultraviolet light (e.g., 365nm-405nm), ensuring efficient polymerization initiation at different depths and achieving uniform curing of thick-section samples.

[0042] In another preferred embodiment of the present invention, the zirconium oxide nanocrystals are ZrO2 nanocrystals with a particle size of 5-10 nm. Specifically, by using ZrO2 nanocrystals with a particle size of 5-10 nm as an inorganic core, and sequentially modifying the inner layer and the outer layer, surface-modified core-shell structured zirconium oxide nanoparticles are obtained.

[0043] The inner layer modification (covalent bonding layer) involves chemically coating the surface of ZrO2 nanocrystals with a silane coupling agent containing unsaturated double bonds (such as (3-acryloyloxypropyl)trimethoxysilane, abbreviated as MPS). The purpose is that the acryloyloxy groups in this inner layer can copolymerize with the acrylate monomers in the organic photosensitive monomers, which are the organic phase, during the three-stage UV curing process, forming strong covalent bonds, anchoring the inorganic particles in the organic matrix, and fundamentally preventing interface detachment.

[0044] In another preferred embodiment of the present invention, the outer layer modification (refractive index matching layer) is followed by a second coating using a silane coupling agent containing a high refractive index group (such as phenyltriethoxysilane, abbreviated as PTES) or (3-mercaptopropyl)triethoxysilane, abbreviated as MPTES). The purpose is that this aromatic ring or sulfur atom imparts a high refractive index (n≈1.58-1.62) to the shell, placing it between the inorganic core (n≈2.1) and the organic matrix, which is mainly composed of organic photosensitive monomers (n≈1.68), forming a refractive index gradient transition layer. This minimizes light scattering at the particle-matrix interface and is key to obtaining ultra-low haze transparent materials.

[0045] This invention also provides a method for preparing an organic-inorganic hybrid optical resin. Specifically, the method is a three-stage UV curing method for the organic-inorganic hybrid optical resin, comprising the following steps:

[0046] 1) Weigh out the surface-modified core-shell structured zirconia nanoparticles according to the proportion and add them to the organic photosensitive monomer. Disperse them evenly under light-protected conditions, then add the photoinitiator and continue stirring until completely dissolved. After degassing, obtain the liquid photosensitive resin for later use.

[0047] 2) The liquid photosensitive resin obtained in step 1) is subjected to three-stage UV curing to obtain the organic-inorganic hybrid optical resin.

[0048] It should be noted that hybrid systems of organic-inorganic hybrid optical resins are prone to phase separation and scattering during UV curing, requiring control of the spatial distribution of nanoparticles and synchronous network formation through the curing process. This invention employs a three-stage UV curing process: UV pre-curing, UV flipping and strengthening, and post-curing. The resulting 2mm thick sample exhibits a haze ≤0.5%, polarization stress ≤5nm-cm, and a refractive index gradient |dn-dz| ≤2×10⁻⁶. -3 mm -1The process consists of three stages: Stage 1 (UV pre-curing): Low-intensity, long-wavelength UV light (e.g., 380-420nm) initiates the generation of free radicals or cations from a photoinitiator, causing the resin to initially cross-link and form an oligomer network. This stage reduces volume shrinkage stress and prevents inorganic particles from agglomerating due to rapid curing. Stage 2 (UV re-curing): Switching to high-intensity, short-wavelength UV light (e.g., 240-260nm) accelerates monomer polymerization and network densification. This stage requires careful control of light intensity and time to ensure deep resin curing while avoiding internal stress concentration due to excessive cross-linking. Stage 3 (thermal post-curing): Using medium-wavelength UV light (between the first two stages) for curing and shaping, repairing residual active groups, and improving the material's thermal stability and mechanical strength. Some processes incorporate infrared drying (e.g., 1-2μm wavelength) to remove internal moisture through penetrating heating, enhancing interfacial adhesion. By controlling the inorganic particle size (e.g., 30-50nm) and dispersion uniformity, i.e., utilizing optical properties to regulate transmittance and haze, optical-grade resins with excellent transmittance and haze can be achieved.

[0049] Preferably, in the method for preparing the organic-inorganic hybrid optical resin, the three-stage UV curing is carried out under conditions where the O2 concentration is less than 500 ppm.

[0050] It should also be noted that the core mechanism of the organic-inorganic hybrid optical resin preparation method provided by this invention lies in the proposed "three-stage UV curing molding." By precisely controlling the light intensity and temperature, the formation process of the organic and inorganic networks is guided, achieving a transformation from "uncontrolled phase separation" to "controlled microstructure construction." The raw material used is a pre-prepared RouteC composition, which is a liquid photosensitive resin containing surface-modified ZrO2 nanoparticles, acrylate monomers, silane monomers, and a photoinitiator. The specific process steps are as follows:

[0051] First stage: UV pre-curing (low temperature, low light intensity). Parameters: 3-5 mW-cm², 5-8 min. Purpose and mechanism: This stage is for "gelation control". Low light intensity initiates slow acrylate chain growth, forming an initial organic network with low cross-linking degree, like a "fish trap", "locking" high concentrations of nanoparticles and silane monomers within the trap, greatly limiting their migration and aggregation. At the same time, the low reaction rate releases less heat, avoiding runaway polymerization caused by local overheating. This stage is the most critical step in controlling the uniform distribution of nanoparticles.

[0052] Second stage: UV flipping and strengthening (medium-high light intensity). Parameters: 15-20mW-cm², 20-30min, flipping required midway. Purpose and mechanism: This stage is for "main network construction". Under medium-high light intensity, the acrylate monomers fixed by the "fish trap" undergo deep polymerization, forming a high-conversion, high-strength main organic network, giving the material basic mechanical strength. The process emphasizes repeated flipping and light irradiation to compensate for light attenuation, ensuring that both the top and bottom surfaces of the thick cross-section sample are fully cured, thereby effectively reducing the refractive index gradient.

[0053] Third stage: Post-curing (heating). Parameters: 80-100℃, 1-2h. Purpose and mechanism: This stage is for "inorganic network formation and stress release". Heating provides energy for the hydrolysis and condensation reaction of silane monomers, enabling the "in-situ" formation of cross-linked silicon-oxygen (-Si-O-Si-) inorganic networks within the framework of the organic network. This not only further enhances the hardness and modulus of the material, but more importantly, this gentle heating process allows the polymer chains to relax, releasing most of the internal stress accumulated during the UV curing stage.

[0054] This invention also provides an organic-inorganic hybrid optical resin prepared using the above-described method. This preparation method, used as a low-scattering, thick-section molding process, is suitable for low-haze, low-stress molding of thick-section transparent parts, and belongs to the curing process of the ORMOSIL-nanoparticle hybrid system.

[0055] This invention also provides an application of the aforementioned organic-inorganic hybrid optical resin in the fabrication of optical components, optoelectronic devices, coatings, adhesives, etc. It is particularly suitable as a material for fabricating low-scattering, thick-section transparent parts, exhibiting characteristics of low haze and low-stress molding, and showing broad application prospects in multiple fields such as optical components (especially optical lenses) and optoelectronic devices. With continuous technological advancements and increasing market demand, the aforementioned organic-inorganic hybrid optical resin is expected to play an even more important role in the future.

[0056] Optical components, in particular, refer to devices used to control, regulate, convert, and manipulate optical signals, playing a crucial role in optical systems and instruments. Based on their functions and properties, optical components can be categorized into various types, broadly including optical lenses, light source devices, laser elements, photodetectors, optical modulators, and some optical transmission components. Optoelectronic devices typically include semiconductor photodetectors, photomultiplier tubes, low-light image intensifiers, vacuum camera tubes, cooled and uncooled infrared imaging devices, ultraviolet imaging devices, and X-ray imaging devices, finding wide applications in fields such as home video cameras, mobile phone cameras, night vision goggles, low-light cameras, infrared detection, infrared guidance, infrared remote sensing, fingerprint detection, missile detection, medical testing, and X-ray imaging.

[0057] The technical effects of the organic-inorganic hybrid optical resin of the present invention will be further explained below by listing specific embodiments.

[0058] Example 1

[0059] An organic-inorganic hybrid optical resin comprises the following raw materials: surface-modified core-shell zirconia nanoparticles, organic photosensitive monomers, hydrolyzable silane crosslinking agents, and photoinitiators; wherein the surface-modified core-shell zirconia nanoparticles are prepared by coating zirconia nanocrystals with silane coupling agents containing unsaturated double bonds and silane coupling agents containing high refractive index groups, respectively.

[0060] In this embodiment, the preparation method of the organic-inorganic hybrid optical resin specifically includes the following steps:

[0061] 1) Preparation of core-shell structured zirconia nanoparticles via surface functionalization of ZrO2 nanoparticles. Take 100g of acetic acid-stabilized ZrO2 nanoparticle sol with a solid content of 20wt% and an average particle size of 5-7nm (specifically, existing nano-zirconia products such as VK-R20W and VK-R20C can be used, with isopropanol as the solvent). Add the above ZrO2 nanoparticle sol to a 500mL reaction flask equipped with a stirrer, dropping funnel, and condenser, and then add 100mL of isopropanol. Start stirring. Add a small amount of ammonia water (28wt% ammonia concentration as a hydrolysis condensation catalyst) to adjust the pH of the system to 9-10 to promote the hydrolysis of silanes. The first coating layer is then applied: The first coupling agent (MPS), namely (3-acryloxypropyltrimethoxysilane), is weighed out and used for subsequent covalent bonding with the acrylate matrix. MPS (the amount is calculated based on a ligand density target of 2.2 mmol-m²) is dissolved in a small amount of isopropanol and slowly added dropwise to the reaction mixture using a dropping funnel. The mixture is stirred at 60°C for 6-8 hours to form a tight acrylate functionalized inner shell. The second coating layer is then applied: The second coupling agent (PTES), namely phenyltriethoxysilane, is weighed out and used to construct a refractive index-matched shell to reduce scattering. After the first layer reaction is complete, PTES (the amount is calculated based on a refractive index gradient matching model) is dissolved in isopropanol and slowly added dropwise to the reaction system. The mixture is stirred at 60°C for another 4-6 hours to form a refractive index-gradient outer shell. After the reaction is complete, most of the solvent and reaction byproducts (such as methanol and ethanol) are removed by rotary evaporation to obtain a concentrated slurry of ZrO2 nanoparticles with a double-layer surface modification, namely the core-shell structured zirconia nanoparticles.

[0062] 2) Organic photosensitive monomers are obtained through the formulation of hybrid resins. A mixture of high-refractive-index aromatic acrylate (specifically trifunctional aromatic epoxy acrylate) and low-viscosity aliphatic acrylate (specifically isobornyl acrylate) is premixed to adjust the viscosity and refractive index (n≈1.68) of the final resin.

[0063] 3) Preparation of liquid photosensitive resin. A concentrated slurry of ZrO2 nanoparticles with a double-layer surface modification is added to an organic photosensitive monomer. Under light-protected conditions, high-speed mechanical stirring or ultrasonic dispersion is performed until a clear, transparent, and homogeneous liquid resin is formed. Then, a mixed photoinitiator is added, and stirring continues until completely dissolved. Vacuum degassing is then performed to remove air bubbles introduced during mixing. The final RouteC composition (i.e., liquid photosensitive resin) is a pale yellow transparent liquid, in which the surface-modified ZrO2 nanoparticles (total solid content approximately 35 wt%) are stably dispersed in a photosensitive acrylate matrix, which can be directly used in subsequent three-stage UV curing molding processes. The photoinitiator is a mixed photoinitiator system, specifically a mixture of initiator TPO (Diphenyl(2,4,6-trimethylbenzoyl)phosphine oxide) and initiator Irgacure819 (Bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide), typically mixed in equal weights, with a total addition amount of 1.2 wt%.

[0064] 4) The liquid photosensitive resin obtained in step 3) is subjected to three-stage UV curing (i.e., a three-stage UV curing process is used, see details). Figure 1 As shown, specifically, a three-stage UV hybrid curing program curve is used to obtain the organic-inorganic hybrid optical resin. The three-stage UV curing process includes three steps: UV pre-curing, UV flipping strengthening, and thermal post-curing. UV pre-curing involves injecting the RouteC composition into a 2mm thick mold. Irradiation is performed for 6 minutes in a glove box under nitrogen protection (O2 < 500ppm) using a 395-405nm LED light source at a light intensity of 4mW-cm². UV flipping strengthening involves increasing the light intensity to 18mW-cm² and continuing irradiation for 25 minutes. Then, flipping is performed for repeated strengthening, specifically by rotating the mold 180 degrees and irradiating again at a light intensity of 18mW-cm² for 25 minutes. Thermal post-curing involves placing the cured sample in a 90℃ oven and heating at that temperature for 1.5 hours. Finally, demolding and cooling are performed: the sample is removed, cooled to room temperature, and then demolded to obtain the organic-inorganic hybrid optical resin, i.e., the final optical element.

[0065] The quality control and release thresholds are as follows:

[0066] Optical performance values: Haze ≤ 0.5% for 2mm sample; Polarizing stress ≤ 5nm-cm; Refractive index gradient |dn-dz| ≤ 2×10 -3 mm -1 .

[0067] Nanophase stability: DLS online monitoring showed PDI remained <0.1; no particle size increase; no phase separation texture. See details. Figure 2 The figure shows a schematic diagram of the nanophase stability (DLS online monitoring) results during the three-stage UV curing process. The DLS online monitoring curve shows the relationship between PDI, average particle size and time.

[0068] Curing: Organic phase conversion rate ≥92%; complete curing after silicon-oxygen network (Si-O-Si signal enhancement, FTIR-solid NMR).

[0069] Statistics: n≥5; mean ± standard deviation; significance test compared with single-segment curing control (p<0.05).

[0070] Performance testing

[0071] To verify the performance of the organic-inorganic hybrid optical resin provided by this invention, a control group was set up: the RouteC composition identical to that in Example 1 was injected into a 2mm thick mold. Curing was performed under the same nitrogen protection environment using a conventional single-stage process: single-stage UV curing used a 395-405nm LED light source, directly irradiating one side continuously for 35 minutes at a light intensity of 20mW-cm² (a common parameter in the prior art) (the total light energy was close to that of the UV stage in Example 1 of this invention). Then, the sample was demolded and cooled to room temperature to obtain the final sample.

[0072] Specifically, the control group used a traditional single-stage process, employing the exact same RouteC composition as in Example 1 of this invention, with the only difference being the curing process. The control group used a conventional single-stage high-strength UV curing process known in the art. Detailed steps are as follows:

[0073] 1) Raw material preparation: Take the RouteC composition prepared by the method in Example 1 and inject it into an identical 2mm thick quartz glass mold.

[0074] 2) Environmental control: The mold filled with resin is placed in a glove box with a nitrogen atmosphere (O2 concentration <500ppm) to eliminate the interference of oxygen inhibition on the curing effect and ensure that the environmental conditions are consistent with those in Example 1 of this invention.

[0075] 3) Single-stage UV curing: Using an LED surface light source with a wavelength of 395-405nm, the mold is continuously irradiated on one side for 35 minutes with a constant light intensity of 20mW-cm². No post-heating curing: After UV irradiation, no heating treatment is performed, and the sample is directly left to stand at room temperature. Demolding is performed after cooling to room temperature.

[0076] Parameter selection explanation: 20mW-cm² was chosen because this is a typical light intensity parameter used in existing technologies to achieve rapid and deep curing. An irradiation time of 35 minutes was chosen to ensure that the total exposure energy (20mW-cm² × 35min × 60s-min = 42,000mJ-cm²) is approximately equivalent to the total energy of the UV curing stage in this embodiment of the invention ((4×6 + 18×25) × 2 × 60 ≈ 57,000mJ-cm²), thus guaranteeing a fair comparison.

[0077] Furthermore, the final samples of the organic-inorganic hybrid optical resin obtained in Example 1 and the control group were subjected to haze and polarization stress tests. Specific results are shown in [link to results]. Figure 4 The figure shows a comparison of haze and polarization stress test results between the organic-inorganic hybrid optical resin and the control group. Haze comparison (n=5, mean ± SD).

[0078] from Figure 4 As can be seen, for the organic-inorganic hybrid optical resin obtained in Example 1, the haze of the final sample was measured to be 0.29±0.05% (p<0.001), and the polarization stress was 4.8±0.5 nm-cm. The haze of the final sample of the control group was measured to be 0.83±0.12%, and the polarization stress was 15.2±1.8 nm-cm.

[0079] It should be noted that the specific optical performance testing methods in all embodiments of the present invention are performed according to the following:

[0080] 1) Haze and transmittance.

[0081] Instrument: BYKHaze-GardPlus haze meter.

[0082] Standard: Complies with ASTM D1003 standard.

[0083] Samples: After curing and demolding, 2mm thick samples were polished, cleaned, and then tested. Five samples were tested for each formulation and process condition, and the average value was taken.

[0084] Release threshold is based on the following: a haze of ≤0.5% is the acceptable upper limit for highly transparent optical elements.

[0085] 2) Stress Birefringence.

[0086] Instrument: Strainoptics PS-100 polarizing stress meter or a polarizing microscope based on a similar principle.

[0087] Method: A 2mm thick circular sample (50mm in diameter) was placed in an orthogonal polarization field, and the interference fringes were observed. The optical path difference (retardation) caused by internal stress was measured using the Senarmont compensation method, and the polarization stress value was calculated based on the sample thickness.

[0088] Unit: nm-cm.

[0089] The release threshold is based on the requirement that ≤5nm-cm is a strict requirement in precision optical applications to avoid the impact of stress birefringence on imaging quality.

[0090] 3) Refractive index gradient.

[0091] Instrument: Metricon 2010-M prism coupler.

[0092] Method: A 2mm thick sample was cut along the thickness direction (Z-axis), and the cut surfaces were precision polished. The refractive indices n1 and n2 near the upper and lower surfaces (z=0 and z=2mm) of the polished surface were measured using a prism coupler. The refractive index gradient was calculated using the formula |dn-dz|=|n1-n2|-thickness.

[0093] Release threshold based on: ≤2×10 -3 mm -1 Ensuring a high degree of consistency in refractive index across the entire component thickness is a key indicator for eliminating imaging distortion and chromatic aberration.

[0094] Figure 3 This image shows the refractive index gradient measurement results of an organic-inorganic hybrid optical resin according to an embodiment of the present invention. Specifically, it includes a measurement diagram and a depth distribution curve. Figure 3 It can be seen that, for the organic-inorganic hybrid optical resin obtained in Example 1, the refractive index gradient |dn-dz| of the 2 mm thick sample is ≤2×10⁻⁶. -3 mm -1 .

[0095] It should be noted that hybrid systems of organic-inorganic hybrid optical resins are prone to phase separation and scattering during UV curing, requiring control of the spatial distribution of nanoparticles and synchronous network formation through the curing process. This invention employs a three-stage UV curing process: UV pre-curing, UV flipping and strengthening, and post-curing. The resulting 2mm thick sample exhibits a haze ≤0.5%, polarization stress ≤5nm-cm, and a refractive index gradient |dn-dz| ≤2×10⁻⁶. -3 mm -1The process consists of three stages: Stage 1 (UV pre-curing): Low-intensity, long-wavelength UV light (e.g., 380-420nm) initiates the generation of free radicals or cations from a photoinitiator, causing the resin to initially cross-link and form an oligomer network. This stage reduces volume shrinkage stress and prevents inorganic particles from agglomerating due to rapid curing. Stage 2 (UV re-curing): Switching to high-intensity, short-wavelength UV light (e.g., 240-260nm) accelerates monomer polymerization and network densification. This stage requires careful control of light intensity and time to ensure deep resin curing while avoiding internal stress concentration due to excessive cross-linking. Stage 3 (thermal post-curing): Using medium-wavelength UV light (between the first two stages) for curing and shaping, repairing residual active groups, and improving the material's thermal stability and mechanical strength. Some processes incorporate infrared drying (e.g., 1-2μm wavelength) to remove internal moisture through penetrating heating, enhancing interfacial adhesion. By controlling the inorganic particle size (e.g., 30-50nm) and dispersion uniformity, i.e., utilizing optical properties to regulate transmittance and haze, optical-grade resins with excellent transmittance and haze can be achieved.

[0096] It should also be noted that this invention enables the "synergistic generation" of organic-inorganic networks, reducing scattering. Its core principle lies in separating the time and energy dimensions, decomposing the two network generation processes with vastly different chemical properties and reaction kinetics from a chaotic, competitive "one-step reaction" into an ordered, relay-style "three-step reaction." The drawbacks of traditional processes (i.e., why synergy is impossible): In traditional single-stage high-intensity UV curing, the photoinitiator instantly generates a large number of free radicals, triggering an explosive chain polymerization of acrylate monomers. This process reaches extremely high conversion rates within seconds to minutes, releasing a large amount of heat. This causes two problems:

[0097] 1) Kinetic mismatch: The formation rate of organic networks (seconds to minutes) is much faster than the hydrolysis and polycondensation rate of inorganic silicon-oxygen networks (minutes to hours). Organic networks solidify instantly, "freezing" unreacted silane monomers within them. Even with subsequent heating, it is difficult to form a continuous and complete inorganic network due to steric hindrance.

[0098] 2) Uncontrolled phase separation: The intense polymerization reaction leads to a sharp increase in the system viscosity, while the local temperature rises, exacerbating the Brownian motion and aggregation tendency of nanoparticles. The final result is a highly non-uniform, non-ideal structure composed of "polymer clumps" and "nanoparticle clusters".

[0099] The principle of collaborative generation in this invention (i.e., how to achieve collaboration) is as follows: The three-stage process of this invention cleverly solves the above problems, achieves "collaboration," and results in thick sheets with uniform curing, low stress, and good dimensional stability.

[0100] 1) First stage (UV pre-curing): Organic network "sets the stage", inorganic network "takes place".

[0101] Slow polymerization induced by low light intensity forms a gel network with low cross-linking degree. This network is "flexible," effectively inhibiting the macroscopic migration of nanoparticles (preventing aggregation) while providing ample reaction space and a certain degree of freedom for the silane monomers. At this point, the organic network provides a uniformly distributed reaction "stage" for the inorganic network to be formed.

[0102] 2) Second stage (UV reinforcement): Organic network “performs”, inorganic network “waits”.

[0103] High-intensity light causes the organic network to further cross-link and solidify, forming a robust "protagonist" framework that gives the material its macroscopic shape and strength. At this stage, the system temperature is still not high, and the hydrolysis and condensation reaction rate of silane monomers is extremely low. They are still uniformly dispersed in the organic network framework in the form of monomers or oligomers, "patiently waiting" for the next instruction.

[0104] 3) The third stage (heat-cured solidification): Inorganic networks "take the stage" and "perfectly harmonize" with organic networks.

[0105] Heating acts as a "switch" to initiate the formation of the inorganic network. Heat induces the hydrolysis and condensation of silane monomers within the "nanoreactor" of the organic network framework, generating a continuous -Si-O-Si-inorganic network "in-situ." Since the organic network is already established at this point, the formation of the inorganic network is confined to the nanoscale space, thus creating a structure that interpenetrates with the organic network.

[0106] To further verify the performance of the organic-inorganic hybrid optical resin, the nanophase stability was characterized below. Specifically, the particle size distribution and microstructure of the organic-inorganic hybrid optical resin in Example 1 were observed. This included:

[0107] 1) Particle Size and PDI

[0108] Instrument: Malvern Zetasizer NanoZS Dynamic Light Scattering (DLS) instrument.

[0109] Methods: For online monitoring, small amounts of liquid resin samples were taken at different curing stages (before pre-curing, after pre-curing, and after strengthening), diluted with a large amount of tetrahydrofuran, and immediately subjected to DLS testing. The PDI value (polydispersity index) was directly provided by the instrument software.

[0110] Release threshold criteria: PDI < 0.1 indicates that the nanoparticles are a monodisperse system, which is a prerequisite for preventing agglomeration and ensuring low scattering. No significant increase in particle size (e.g., increase < 10%) proves the stability of the process.

[0111] 2) Microstructure and phase separation

[0112] Instrument: FEITecnaiG2F20 transmission electron microscope (TEM).

[0113] Methods: Thin slices of 50-70 nm thickness were prepared from the final cured sample using an ultramicrotome (Leica EMUC7). The dispersion state of nano-ZrO2 particles in the organic matrix was observed by TEM.

[0114] Judgment criteria: At high magnification, the nanoparticles appear as uniformly dispersed independent individuals, with no obvious aggregation or micron-scale phase separation structure observed.

[0115] To further verify the formation principle of the described organic-inorganic hybrid optical resin, the degree of curing was characterized below. Specifically, the organic phase conversion rate and silicon-oxygen network formation of the organic-inorganic hybrid optical resin in Example 1 were explored. This included:

[0116] 1) Organic phase conversion rate (Conversion Rate)

[0117] Instrument: Bruker Vertex 70 Fourier Transform Infrared Spectrometer (FTIR) with Attenuated Total Reflectance (ATR) accessory.

[0118] Methods: The characteristic peak of the C=C double bond stretching vibration of acrylate functional groups (approximately 810 cm⁻¹) was tracked. -1 The change in area before and after curing. A peak unaffected by the reaction (e.g., the C=O ester carbonyl peak, approximately 1720 cm⁻¹) is used. -1 () is used as an internal standard. The conversion rate is calculated using the formula (1-(A_t-A_ref_t)-(A_0-A_ref_0))×100%.

[0119] Release threshold basis: A high conversion rate of ≥92% is the basis for ensuring that the material obtains excellent mechanical properties and chemical stability.

[0120] 2) Formation of silicon-oxygen networks

[0121] Instrument: FTIR or Bruker Avance III solid-state nuclear magnetic resonance spectrometer.

[0122] Method (FTIR): Compare the samples before and after thermal curing, and observe the Si-O-Si stretching vibration peaks (at 1000-1100 cm⁻¹). -1The significant enhancement of a broad peak within the range qualitatively demonstrates the formation and cross-linking of silicon-oxygen networks.

[0123] Method (²) 9 SissNMR: This is a more precise quantitative method. By analyzing T... 0 By calculating the relative contents of different silicon species such as T¹, T², and T³, the degree of condensation of silane monomers can be determined, thereby quantitatively characterizing the integrity of the silicon-oxygen network.

[0124] Judgment criteria: After post-curing, the Si-O-Si signal is significantly enhanced, or² 9 Siss NMR showed that the T² and T³ signals were dominant, indicating that the inorganic network had been fully formed.

[0125] It should be noted that the above tests employed statistical analysis, meaning all performance tests used a sample size of n≥5. Experimental data are expressed as mean ± standard deviation (Mean ± SD). Using statistical software such as SPSS or Origin, a two-sample t-test (Student's-test) was employed to compare the data of the embodiments of this invention with the single-segment solidification control group. Significance level: p<0.05 was used as the criterion for statistically significant difference.

[0126] Example 2

[0127] Compared with Example 1, except that the raw materials of the organic-inorganic hybrid optical resin are in the following weight ratios: 30 parts of surface-modified core-shell structured zirconia nanoparticles, 50 parts of organic photosensitive monomer, 3 parts of hydrolyzable silane crosslinking agent, and 0.5 parts of photoinitiator, everything else is the same as in Example 1. The preparation methods are all the same as in Example 1, and will not be repeated here.

[0128] Example 3

[0129] Compared with Example 1, except that the raw materials of the organic-inorganic hybrid optical resin are in the following weight ratios: 45 parts of surface-modified core-shell structured zirconia nanoparticles, 65 parts of organic photosensitive monomer, 8 parts of hydrolyzable silane crosslinking agent, and 2 parts of photoinitiator, everything else is the same as in Example 1. The preparation methods are all the same as in Example 1, and will not be repeated here.

[0130] Example 4

[0131] Compared with Example 1, except that the raw materials of the organic-inorganic hybrid optical resin are in the following weight ratios: 30 parts of surface-modified core-shell structured zirconia nanoparticles, 65 parts of organic photosensitive monomer, 8 parts of hydrolyzable silane crosslinking agent, and 2 parts of photoinitiator, everything else is the same as in Example 1. The preparation method is the same as in Example 1, and will not be repeated here.

[0132] Example 5

[0133] Compared with Example 1, except that the raw materials of the organic-inorganic hybrid optical resin are in the following weight ratios: 45 parts of surface-modified core-shell structured zirconia nanoparticles, 50 parts of organic photosensitive monomer, 3 parts of hydrolyzable silane crosslinking agent, and 1 part of photoinitiator, everything else is the same as in Example 1. The preparation methods are all the same as in Example 1, and will not be repeated here.

[0134] Example 6

[0135] Compared with Example 1, except that the first coupling agent is silane coupling agent KH-570 (which has a methacryloyloxy functional group containing an unsaturated double bond and three hydrolyzable methoxy functional groups in its molecular structure) and the second coupling agent is (3-mercaptopropyl)triethoxysilane (abbreviated as MPTES), everything else is the same as Example 1.

[0136] Example 7

[0137] Compared with Example 1, except that the first layer coupling agent is silane coupling agent KH-560, everything else is the same as Example 1.

[0138] Example 8

[0139] Compared with Example 1, except that the UV pre-curing was carried out under a light intensity of 3mW-cm² for 8 minutes, the UV flipping strengthening was carried out under a light intensity of 15mW-cm² for 30 minutes, and the heat curing was carried out at 80°C for 2 hours, everything else was the same as Example 1.

[0140] Example 9

[0141] Compared with Example 1, except that the UV pre-curing was carried out under a light intensity of 5mW-cm² for 5 minutes, the UV flipping strengthening was carried out under a light intensity of 20mW-cm² for 20 minutes, and the heat curing was carried out at 100°C for 1 hour, everything else was the same as Example 1.

[0142] Example 10

[0143] Compared with Example 1, except that the high refractive index aromatic acrylate is specifically bis(4-(2-acryloyloxyethylthio)phenyl) sulfide (S-DA) and the low viscosity aliphatic acrylate is specifically dicyclopentadienyldimethyl diacrylate (DCPDA), everything else is the same as Example 1.

[0144] Based on the above results, the beneficial effects of the embodiments of the present invention are as follows: By rationally using raw materials such as surface-modified core-shell structured zirconia nanoparticles, organic photosensitive monomers, hydrolyzable silane crosslinking agents, and photoinitiators, and employing a three-stage UV curing molding process, the embodiments of the present invention can effectively reduce the haze and stress of the material, while improving the refractive index. This results in an organic-inorganic hybrid optical resin with a haze ≤0.5%, polarization stress ≤5nm-cm, and a refractive index gradient ≤2×10⁻⁶. -3 mm -1 Compared to traditional single-stage UV curing processes, this invention solves the problem that existing organic-inorganic hybrid optical resins, when used to produce thick-section optical components, typically cannot simultaneously achieve high refractive index, ultra-low haze, and ultra-low stress. Furthermore, the preparation method of the organic-inorganic hybrid optical resin provided in this invention is simple, employing a three-stage UV curing process. By using low-intensity UV pre-curing, precise control of the nanophase separation process is achieved, reducing haze by 65% ​​(from 0.83% to 0.29%). Through post-heat curing, effective release of internal stress is achieved, reducing polarization stress by 68% (from 15.2 nm-cm to 4.8 nm-cm). By using UV flipping reinforcement, uniform curing of the upper and lower surfaces of the thick component is achieved, controlling the refractive index gradient within 2 × 10⁻⁶. -3 mm -1 The following methods are easily implemented on existing 405nm UV equipment and ovens, suitable for mass production of lenses and optical modules, and have broad market prospects.

[0145] It should be noted that this invention aims to solve the technical problem in the prior art of using organic-inorganic hybrid optical resins to prepare optical elements with thick cross-sections (>1 mm), where it is difficult to simultaneously control nanophase separation, internal stress, and curing uniformity, resulting in high haze, high stress, and non-uniform refractive index in the final product. Interface compatibility is key and is the innovation of this invention's organic-inorganic hybrid optical resin. Organic-inorganic interface compatibility is a decisive factor in the performance of hybrid materials. This invention does not use conventional physical blending but develops a novel core-shell structure surface modification technique. Specifically, this includes covalent bond anchoring: a first layer of acryloyloxy-containing silane (MPS) achieves covalent bond connection between inorganic nanoparticles and the organic matrix, which is the strongest interfacial bonding method; and refractive index gradient matching: a second layer of phenyl-containing silane (PTES) constructs a refractive index gradient layer on the particle surface, effectively reducing Rayleigh scattering of light at the interface. Therefore, the "covalent anchoring + gradient matching" dual-layer surface modification technology fundamentally solves the scattering problem caused by interface defects. This is the core innovation of the organic-inorganic hybrid optical resin part in this invention, and it is also the basis for the successful implementation of subsequent processes.

[0146] It should be further explained that the innovations and beneficial effects of this invention are closely related. Its core lies in the introduction of a "process control" concept absent in traditional single-stage curing. This invention is not a simple parameter adjustment of existing UV curing processes, but rather a completely new, phased, multi-mode curing "methodology." Its core innovations are: the introduction of a "low-intensity pre-curing" stage: this is "active control" of reaction kinetics, used to construct an initial gel network that restricts nanoparticle aggregation; emphasis on "double-sided exposure": this is a crucial step for ensuring uniform curing of thick parts, used to eliminate refractive index gradients; and the combination of "mild post-curing": this is a "secondary optimization" of the network structure and stress, used to generate inorganic networks in situ and release internal stress. The specific beneficial effects brought about by the changes in the key process parameters (innovations) of this invention compared to existing technologies are as follows:

[0147] 1. UV Pre-curing Stage (3-5 mW-cm²). Existing technologies typically use high light intensity (above 20 mW-cm²) for one-time curing. This invention innovatively introduces a low-intensity pre-curing step, resulting in the following beneficial effects: ① Controlled nanophase separation: Effectively inhibits nanoparticle aggregation, which is the fundamental reason for achieving low haze (<0.3%) in the final product. ② Homogenization reaction: Provides a uniform reaction substrate for subsequent curing.

[0148] 2. UV Flipping Enhancement Stage (Flipping Operation). Existing technologies rarely consider light attenuation when curing thick parts. This invention explicitly requires flipping and double-sided exposure of thick parts, resulting in the following benefits: ① Reducing the refractive index gradient: ensuring uniform curing on both the upper and lower surfaces of the sample, and controlling the refractive index gradient (dn-dz) within 2×10⁻⁶. -3 mm -1 The following measures ensured optical imaging quality. ② Improved overall conversion efficiency.

[0149] 3. Introducing a post-heat curing stage (80-100℃). Existing technologies mostly use pure UV curing. This invention creatively combines UV curing with gentle heat curing, resulting in the following beneficial effects: ① Significantly reduced internal stress: Heat treatment promotes stress relaxation, reducing polarization stress from greater than 15 nm-cm to less than 5 nm-cm, greatly improving the dimensional stability and optical performance of the product. ② Formation of a hybrid network: Promotes the formation of a silicon-oxygen network, improving material hardness and durability.

[0150] 4. Process Monitoring (DLS and O2 < 500 ppm). Including online DLS monitoring and strict oxygen concentration control as part of the process is something neglected in existing technologies. The beneficial effects of this invention through process monitoring include: ① Ensuring process stability and repeatability: Online monitoring ensures that nanoparticles do not agglomerate throughout the curing process (PDI < 0.1). ② Ensuring high conversion rate: The low-oxygen environment avoids oxygen inhibition of polymerization, ensuring the quality of surface curing.

[0151] Moreover, the method for preparing organic-inorganic hybrid optical resin provided in this invention, as a low-scattering thick-section molding process, is most innovative in that it perfectly combines advanced "material design" (liquid photosensitive resin) with sophisticated "process control" (three-stage UV curing), providing a complete solution from raw materials to finished products. It does not solve a problem in isolation, but systematically overcomes all the key obstacles in preparing high-quality hybrid optical thick parts, achieving the "impossible triangle" of performance: simultaneously obtaining high refractive index, ultra-low haze, and ultra-low stress, which are impossible to achieve with traditional processes. At the same time, it expands the size and application range of products: enabling the application of high-performance hybrid resins to successfully extend from traditional thin-film coatings to millimeter-level and above thick-section precision optical components, such as VR-AR lenses and automotive optical modules, with enormous industrial application value. Furthermore, it has good process compatibility: the entire process only relies on existing standard 405nm UV equipment and ovens, requiring no expensive modifications to the production line, making it easy to achieve industrial mass production.

[0152] Therefore, the innovation of this invention is not a simple adjustment of a single parameter, but a complete set of synergistic process flows. The three core innovations—low-intensity pre-curing, flipping strengthening, and post-heat curing—are interconnected and jointly solve the three major challenges of haze, stress, and uniformity in the molding of thick hybrid resin parts, achieving comprehensive performance unattainable by existing technologies. By utilizing a three-stage UV curing method as a low-scattering thick-section molding process, it can be adapted for low-haze and low-stress molding of thick-section transparent parts, showing broad application prospects in multiple fields such as optical lenses and optoelectronic devices. For example, the optical components used in liquid crystal displays typically have structures such as polarizing films, phase difference films, and anti-reflective films, which can exhibit various functions. The aforementioned organic-inorganic hybrid optical resin can be used in the materials of these optical components. Furthermore, optical components containing these resin materials are not limited to those used in liquid crystal displays, but are also used in various optical-related devices. For example, in addition to the above, they can also be used as lenses in optical disc signal reading lens systems, Fresnel lenses for projection screens, plastic lenses for biconvex lenses, and other functional components requiring superior optical properties.

[0153] Finally, it should be noted that the raw materials such as KH-570 used in this invention can all be products from existing manufacturers. For example, KH-570 can be a product manufactured by Merck Life Sciences, Condis Chemicals (Hubei) Co., Ltd., or Nanjing Nengde New Material Technology Co., Ltd. These are all conventional additives used in the production of optical resins; the specific selection is based on requirements and will not be elaborated upon here.

[0154] The preferred embodiments of the present invention have been described in detail above, outlining the basic principles, main features, and advantages of the invention. However, those skilled in the art should understand that the embodiments of the present invention are not limited to the above-described embodiments. The embodiments and descriptions in the specification are merely preferred examples of the present invention and are not intended to limit the invention. Within the scope of knowledge possessed by those skilled in the art, various changes can be made without departing from the spirit of the embodiments of the present invention. It is neither necessary nor possible to exhaustively describe all embodiments here. However, obvious changes or modifications derived therefrom are still within the protection scope of the embodiments of the present invention.

Claims

1. An organic-inorganic hybrid optical resin, characterized in that, The organic-inorganic hybrid optical resin comprises the following raw materials by weight: 30-45 parts of surface-modified core-shell zirconia nanoparticles, 50-65 parts of organic photosensitive monomer, 3-8 parts of hydrolyzable silane crosslinking agent, and 0.5-2 parts of photoinitiator; wherein, the organic photosensitive monomer is a mixture of multifunctional acrylate monomer and reactive diluent; the surface-modified core-shell zirconia nanoparticles are prepared by coating zirconia nanocrystals with silane coupling agents containing unsaturated double bonds and silane coupling agents containing high refractive index groups, respectively; the organic-inorganic hybrid optical resin is prepared by surface-modified core-shell zirconia nanoparticles... Zirconia nanoparticles with shell structure are added to an organic photosensitive monomer and dispersed evenly under light-protected conditions. Then, a photoinitiator and a hydrolyzable silane crosslinking agent are added and stirred until completely dissolved. After degassing, a liquid photosensitive resin is obtained, which is then subjected to a three-stage UV curing process. The three-stage UV curing process includes three steps: UV pre-curing, UV flipping and strengthening, and thermal curing. The UV pre-curing is performed by irradiation at a light intensity of 3-5 mW / cm² for 5-8 minutes. The UV flipping and strengthening is performed by irradiation at a light intensity of 15-20 mW / cm² for 20-30 minutes. The thermal curing is performed by heating at 80-100℃ for 1-2 hours.

2. The organic-inorganic hybrid optical resin according to claim 1, characterized in that, The organic-inorganic hybrid optical resin has a haze ≤0.5%, a polarization stress ≤5nm / cm, and a refractive index gradient ≤2×10⁻⁶. -3 mm -1 .

3. A method for preparing an organic-inorganic hybrid optical resin as described in any one of claims 1-2, characterized in that, Includes the following steps: 1) Weigh out the surface-modified core-shell structured zirconia nanoparticles according to the proportion and add them to the organic photosensitive monomer. Disperse them evenly under light-protected conditions, then add the photoinitiator and hydrolyzable silane crosslinking agent and continue stirring until completely dissolved. After degassing, liquid photosensitive resin is obtained. 2) The liquid photosensitive resin obtained in step 1) is subjected to three-stage UV curing to obtain the organic-inorganic hybrid optical resin.

4. The method for preparing the organic-inorganic hybrid optical resin according to claim 3, characterized in that, In the preparation method of the organic-inorganic hybrid optical resin, the three-stage UV curing is carried out under conditions where the oxygen concentration is less than 500 ppm.

5. The application of an organic-inorganic hybrid optical resin as described in claim 1 or 2 in the preparation of optical lenses.

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