A polyurethane-based photocured resin lens and a method for manufacturing the same

Abstract

This invention discloses a polyurethane-based photocurable resin lens and its preparation method, relating to the field of optical resin lens technology. It is prepared from the following components in parts by weight: 30-40 parts of fluorosilicone block polyurethane acrylate oligomer, 10-20 parts of polythiol, 1-3 parts of photoinitiator, 0.05-0.1 parts of red pigment, 0.05-0.1 parts of blue pigment, 1-3 parts of additives, 0.5-2.5 parts of functional additives, 20-30 parts of reactive diluent, and 5-8 parts of other monomers; wherein the other monomers are 1,6-hexamethylene diisocyanate and 3,9-divinyl-2,4,8,10-tetraoxaspiro[5.5]undecane compounded in a mass ratio of (3-5):1. This lens, through optimized formulation, achieves a synergistic improvement in optical performance, mechanical properties, and environmental resistance.

Description

Technical Field

[0001] This invention relates to the field of optical resin lens technology, and in particular to a polyurethane-based photocurable resin lens and its preparation method. Background Technology

[0002] With the rapid development of the consumer electronics and optical instrument industries, higher demands are being placed on the performance of lens materials. They not only need excellent light transmittance but also require thinner, lighter, and higher-performance designs. Polyurethane-based resin lenses, due to their good toughness, impact resistance, and processability, have become one of the mainstream types of resin lenses. However, traditional polyurethane resin lenses typically employ thermosetting processes, which suffer from drawbacks such as long curing cycles, high energy consumption, and low production efficiency, making them unsuitable for the rapid prototyping needs of modern industry.

[0003] Photopolymerization technology, with its advantages of high efficiency, environmental friendliness, and low cost, is widely used in the field of material forming. Applying photopolymerization to the fabrication of polyurethane lenses can shorten curing time to the minute level, significantly improving production efficiency. However, existing polyurethane-based photopolymerization resin systems generally suffer from a technical contradiction: increasing the content of reactive diluent to improve curing speed leads to insufficient cross-linking density of the cured resin, resulting in poor lens abrasion resistance, easy surface scratches, and low heat distortion temperature; while excessively increasing the content of functional group monomers to pursue mechanical properties leads to a surge in system viscosity and a significant increase in curing shrinkage, resulting in cracks, warping, or optical distortion in the lenses. In addition, commercially available polyurethane-based photopolymerization resin lenses have more or less problems such as low refractive index, low Abbe number, poor film adhesion, insufficient impact resistance, and yellowing resistance that need further improvement, failing to meet the performance requirements of mid-to-high-end lenses.

[0004] For example, invention patent document CN109054356B discloses a myopia lens and its preparation method, relating to the field of polymer material preparation and application technology. The myopia lens is made of a photocurable material, which includes the following components by weight: 20-50 parts modified polyurethane acrylate, 30-60 parts modified epoxy acrylate, 10-30 parts polyethylene glycol dimethacrylate, and 0.1-0.2 parts UV absorber. The invention also discloses a method for preparing the myopia lens. This invention can quickly obtain the base film for myopia lenses, reducing production capacity, is environmentally friendly and low-polluting, is mold-friendly during production, can extend the service life of molds, reduce production costs, and produces lightweight, high-transparency, and good whiteness myopia lenses. However, this patent still has technical defects such as high curing shrinkage rate, insufficient lens abrasion and impact resistance, and easy yellowing after long-term use, making it difficult to meet the stringent requirements of high-end optical lenses. Summary of the Invention

[0005] In view of the above, the present invention aims to provide a polyurethane-based photocurable resin lens and its preparation method, which achieves a synergistic improvement in the lens's optical performance, mechanical performance, and environmental resistance by optimizing the formulation.

[0006] To achieve the above objectives, the technical solution adopted by the present invention is as follows: a polyurethane-based photocurable resin lens, prepared from the following components in parts by weight: 30-40 parts of fluorosilicone block polyurethane acrylate oligomer, 10-20 parts of polythiol, 1-3 parts of photoinitiator, 0.05-0.1 parts of red pigment, 0.05-0.1 parts of blue pigment, 1-3 parts of additives, 0.5-2.5 parts of functional additives, 20-30 parts of reactive diluent, and 5-8 parts of other monomers; wherein the other monomers are 1,6-hexamethylene diisocyanate and 3,9-divinyl-2,4,8,10-tetraoxaspiro[5.5]undecane compounded in a mass ratio of (3-5):1.

[0007] Preferably, there are no special requirements for the source of the fluorosilicone block polyurethane acrylate oligomer. In one embodiment of the present invention, the fluorosilicone block polyurethane acrylate oligomer is prepared according to the preparation method of photosensitive fluorosilicone block polyurethane acrylate oligomer in Example 3 of the invention patent document CN102993404B; before use, the polymerization inhibitor is further removed by vacuum distillation.

[0008] Preferably, the polythiol is polythiol 405.

[0009] Preferably, the photoinitiator is at least one of photoinitiator 819 and photoinitiator XBPO.

[0010] Preferably, the red pigment is Pigment Red 176; the blue pigment is Pigment Blue 15:3.

[0011] Preferably, the additives are antioxidants, light stabilizers, coupling agents, and catalysts compounded in a mass ratio of 1:(0.8-1.2):1:(0.3-0.5).

[0012] Preferably, the antioxidant is at least one of antioxidant 1010 and antioxidant 1076.

[0013] Preferably, the light stabilizer is at least one of light stabilizer 770 and light stabilizer 622.

[0014] Preferably, the coupling agent is at least one of silane coupling agent KH550, silane coupling agent KH560, and silane coupling agent KH570.

[0015] Preferably, the catalyst is dibutyltin dilaurate.

[0016] Preferably, the functional additive is a compound of nano-zirconia and nano-zinc sulfide, with a mass ratio of 1:(0.6-1.0); the particle size of the functional additive is 50-100nm.

[0017] Preferably, the active diluent is a mixture of a monofunctional diluent and a difunctional diluent at a mass ratio of 1:(1.2-1.8); wherein the monofunctional diluent is selected from at least one of dicyclopentyl methacrylate and isobornyl methacrylate; and the difunctional diluent is selected from at least one of tripropylene glycol diacrylate and 1,6-hexanediol diacrylate.

[0018] Another objective of this invention is to provide a method for preparing the polyurethane-based photocurable resin lens, comprising the following steps: mixing each component evenly according to weight parts, vacuum degassing, injecting into an optical lens mold, and curing under a nitrogen protective atmosphere using an ultraviolet light curing device to obtain a preliminary shaped lens; then performing a post-curing treatment, cooling to room temperature, and trimming and cleaning to obtain the polyurethane-based photocurable resin lens.

[0019] Preferably, the ultraviolet light wavelength for ultraviolet irradiation curing is 365–405 nm, and the light intensity is 20–80 mW / cm². 2 The curing time is 30-120 seconds.

[0020] Preferably, the post-curing treatment is performed at a temperature of 50–70°C for 1–3 hours.

[0021] Preferably, the vacuum degree of the vacuum degassing is -0.08 to -0.10 MPa, and the degassing time is 10 to 20 min.

[0022] Due to the application of the above technical solution, the present invention has the following beneficial effects: (1) The polyurethane-based photocurable resin lens and its preparation method disclosed in this invention achieve an unexpected comprehensive performance improvement compared with the existing polyurethane photocurable resin lens through the scientific compounding and synergistic effect of each component. In particular, through the synergistic combination of fluorosilicone block polyurethane acrylate oligomer, polythiol and other specific compounded monomers, the technical pain point of the prior art that it is difficult to balance the weather resistance, light transmittance and mechanical strength of the lens is effectively solved. Among them, the fluorosilicone-block polyurethane acrylate oligomer serves as the core film-forming material of the system. The fluorosilicone blocks in its molecular structure not only endow the lens with excellent water resistance, oil resistance, and stain resistance, effectively avoiding the problems of easy dust accumulation and difficulty in cleaning during lens use, but also allow its acrylate groups to fully crosslink with the reactive diluent and other monomers in the system, increasing the resin crosslinking density. After removing the polymerization inhibitor by vacuum distillation, the interference with the photocuring reaction is further reduced, ensuring more complete curing and no residual impurities inside the lens, significantly improving the lens transmittance. The addition of polythiol, in combination with other components, can effectively regulate the photocuring reaction rate, avoiding stress concentration in the system caused by excessively fast reaction, reducing defects such as lens cracking and deformation, and further enhancing the impact resistance and toughness of the lens. This solves the problem of insufficient toughness and easy brittleness of existing polyurethane lenses, achieving a balance between lens hardness and toughness.

[0023] (2) The polyurethane-based photocurable resin lens and its preparation method disclosed in this invention use 1,6-hexanediisocyanate and 3,9-divinyl-2,4,8,10-tetraoxaspiro[5.5]undecane in a specific mass ratio to form a unique synergistic effect with fluorosilicone block polyurethane acrylate oligomer and polythiol, resulting in unexpected technical effects. The spirocyclic structure contained in the molecular structure of 3,9-divinyl-2,4,8,10-tetraoxaspiro[5.5]undecane has excellent rigidity and dimensional stability, which can effectively inhibit shrinkage deformation during resin curing, reduce lens shrinkage, and solve the problems of warping and dimensional deviation that easily occur after existing lenses are cured. At the same time, its vinyl group can undergo synergistic crosslinking reaction with the acrylate group of fluorosilicone block polyurethane acrylate oligomer and the thiol group of polythiol, further improving the crosslinking density of the system and enhancing the mechanical strength and wear resistance of the lens. The synergistic effect of 1,6-hexanediisocyanate and 3,9-divinyl-2,4,8,10-tetraoxaspiro[5.5]undecane ensures the rigidity of the lens while taking into account the flexibility of the resin, so that the lens has high hardness and good impact resistance. This synergistic effect cannot be achieved by a single monomer.

[0024] (3) The polyurethane-based photocurable resin lens and its preparation method disclosed in this invention use nano-zirconia and nano-zinc sulfide with specific particle sizes in a certain proportion as functional additives. The particle size is controlled at 50-100nm and can be uniformly dispersed in the system formed by fluorosilicone block polyurethane acrylate oligomer, reactive diluent and other monomers without affecting the light transmittance of the lens. At the same time, nano-zirconia can improve the refractive index and abrasion resistance of the lens, while nano-zinc sulfide has excellent ultraviolet absorption performance. The two work together to enable the lens to have high refractive index, high abrasion resistance and anti-ultraviolet performance, solving the technical problem that existing lenses cannot achieve high refractive index and anti-ultraviolet and abrasion resistance at the same time. In addition, the molecular chains of nanoparticles and fluorosilicone block polyurethane acrylate oligomers can form physical entanglement, further enhancing the stability of the cross-linking network, improving the weather resistance of the lens, avoiding problems such as yellowing and decreased light transmittance after long-term use of the lens, and extending the service life of the lens. Detailed Implementation

[0025] The following description is intended to disclose the invention and enable those skilled in the art to implement it. The preferred embodiments described below are merely examples, and other obvious variations will occur to those skilled in the art. Example 1

[0026] A polyurethane-based photocurable resin lens is prepared from the following components in parts by weight: 30 parts of fluorosilicone block polyurethane acrylate oligomer, 10 parts of polythiol, 1 part of photoinitiator, 0.05 parts of red pigment, 0.05 parts of blue pigment, 1 part of additives, 0.5 parts of functional additives, 20 parts of reactive diluent, and 5 parts of other monomers; wherein the other monomers are 1,6-hexanediisocyanate and 3,9-divinyl-2,4,8,10-tetraoxaspiro[5.5]undecane compounded in a mass ratio of 3:1.

[0027] The fluorosilicone block polyurethane acrylate oligomer is prepared according to the preparation method of photosensitive fluorosilicone block polyurethane acrylate oligomer in Example 3 of invention patent document CN102993404B; before use, the polymerization inhibitor is further removed by vacuum distillation; the polythiol is polythiol 405; the photoinitiator is photoinitiator 819; the red pigment is pigment red 176; the blue pigment is pigment blue 15:3; the additives are antioxidants, light stabilizers, coupling agents, and catalysts compounded in a mass ratio of 1:0.8:1:0.3; the antioxidants are... The antioxidant is antioxidant 1010; the light stabilizer is light stabilizer 770; the coupling agent is silane coupling agent KH550; the catalyst is dibutyltin dilaurate; the functional additive is a compound of nano-zirconia and nano-zinc sulfide in a mass ratio of 1:0.6; the particle size of the functional additive is 50 nm; the reactive diluent is a mixture of a monofunctional diluent and a difunctional diluent in a mass ratio of 1:1.2; wherein the monofunctional diluent is dicyclopentyl methacrylate; and the difunctional diluent is tripropylene glycol diacrylate.

[0028] A method for preparing a polyurethane-based photocurable resin lens includes the following steps: mixing the components evenly according to their weight proportions, vacuum degassing, injecting the mixture into an optical lens mold, and curing under a nitrogen protective atmosphere using an ultraviolet light curing device to obtain a pre-shaped lens; then performing a post-curing treatment, cooling to room temperature, and trimming and cleaning to obtain the polyurethane-based photocurable resin lens; wherein the ultraviolet light wavelength for ultraviolet light curing is 365 nm, and the light intensity is 20 mW / cm². 2 The curing time is 30 seconds; the post-curing temperature is 50°C and the time is 1 hour; the vacuum degree of the vacuum degassing is -0.08 MPa and the degassing time is 10 minutes. Example 2

[0029] A polyurethane-based photocurable resin lens is prepared from the following components in parts by weight: 33 parts of fluorosilicone block polyurethane acrylate oligomer, 13 parts of polythiol, 1.5 parts of photoinitiator, 0.06 parts of red pigment, 0.06 parts of blue pigment, 1.5 parts of additives, 1 part of functional additives, 23 parts of reactive diluent, and 6 parts of other monomers; wherein the other monomers are 1,6-hexanediisocyanate and 3,9-divinyl-2,4,8,10-tetraoxaspiro[5.5]undecane in a mass ratio of 3.5:1; the fluorosilicone block polyurethane acrylate oligomer is prepared according to the preparation method of photosensitive fluorosilicone block polyurethane acrylate oligomer in Example 3 of invention patent document CN102993404B; before use, the polymerization inhibitor is further removed by vacuum distillation.

[0030] The polythiol is polythiol 405; the photoinitiator is photoinitiator XBPO; the red pigment is pigment red 176; the blue pigment is pigment blue 15:3; the additives are antioxidants, light stabilizers, coupling agents, and catalysts compounded in a mass ratio of 1:0.9:1:0.35; the antioxidant is antioxidant 1076; the light stabilizer is light stabilizer 622; the coupling agent is silane coupling agent KH560; the catalyst is dibutyltin dilaurate; the functional additive is a compound of nano-zirconia and nano-zinc sulfide in a mass ratio of 1:0.7; the particle size of the functional additives is 60nm; the reactive diluent is a mixture of monofunctional and difunctional diluents in a mass ratio of 1:1.4; wherein the monofunctional diluent is isobornyl methacrylate; and the difunctional diluent is 1,6-hexanediol diacrylate.

[0031] A method for preparing a polyurethane-based photocurable resin lens includes the following steps: mixing the components uniformly according to their weight proportions, vacuum degassing, injecting the mixture into an optical lens mold, and curing under a nitrogen protective atmosphere using an ultraviolet light curing device to obtain a pre-shaped lens; then performing a post-curing treatment, cooling to room temperature, and trimming and cleaning to obtain the polyurethane-based photocurable resin lens; wherein the ultraviolet light wavelength for ultraviolet light curing is 375 nm, and the light intensity is 40 mW / cm². 2 The curing time is 50 seconds; the post-curing temperature is 55°C and the time is 1.5 hours; the vacuum degree of the vacuum degassing is -0.085 MPa and the degassing time is 13 minutes. Example 3

[0032] A polyurethane-based photocurable resin lens is prepared from the following components in parts by weight: 35 parts of fluorosilicone block polyurethane acrylate oligomer, 15 parts of polythiol, 2 parts of photoinitiator, 0.08 parts of red pigment, 0.07 parts of blue pigment, 2 parts of additives, 1.5 parts of functional additives, 25 parts of reactive diluent, and 6.5 parts of other monomers; wherein the other monomers are 1,6-hexamethylene diisocyanate and 3,9-divinyl-2,4,8,10-tetraoxaspiro[5.5]undecane in a mass ratio of 4:1; the fluorosilicone block polyurethane acrylate oligomer is prepared according to the preparation method of photosensitive fluorosilicone block polyurethane acrylate oligomer in Example 3 of invention patent document CN102993404B; before use, the polymerization inhibitor is further removed by vacuum distillation.

[0033] The polythiol is polythiol 405; the photoinitiator is photoinitiator 819; the red pigment is pigment red 176; the blue pigment is pigment blue 15:3; the additives are antioxidants, light stabilizers, coupling agents, and catalysts compounded in a mass ratio of 1:1:1:0.4; the antioxidant is antioxidant 1076; the light stabilizer is light stabilizer 770; the coupling agent is silane coupling agent KH570; the catalyst is dibutyltin dilaurate; the functional additive is a compound of nano-zirconia and nano-zinc sulfide in a mass ratio of 1:0.8; the particle size of the functional additives is 80 nm; the reactive diluent is a mixture of monofunctional and difunctional diluents in a mass ratio of 1:1.5; wherein the monofunctional diluent is dicyclopentyl methacrylate; and the difunctional diluent is 1,6-hexanediol diacrylate.

[0034] A method for preparing a polyurethane-based photocurable resin lens includes the following steps: mixing the components evenly according to their weight proportions, vacuum degassing, injecting the mixture into an optical lens mold, and curing under a nitrogen protective atmosphere using an ultraviolet light curing device to obtain a pre-shaped lens; then performing a post-curing treatment, cooling to room temperature, and trimming and cleaning to obtain the polyurethane-based photocurable resin lens; wherein the ultraviolet light wavelength for ultraviolet light curing is 385 nm, and the light intensity is 50 mW / cm². 2 The curing time is 90s; the post-curing temperature is 60℃ and the time is 2h; the vacuum degree of the vacuum degassing is -0.09MPa and the degassing time is 15min. Example 4

[0035] A polyurethane-based photocurable resin lens is prepared from the following components in parts by weight: 38 parts of fluorosilicone block polyurethane acrylate oligomer, 18 parts of polythiol, 2.5 parts of photoinitiator, 0.09 parts of red pigment, 0.08 parts of blue pigment, 2.5 parts of additives, 2 parts of functional additives, 28 parts of reactive diluent, and 7 parts of other monomers; wherein the other monomers are 1,6-hexanediisocyanate and 3,9-divinyl-2,4,8,10-tetraoxaspiro[5.5]undecane in a mass ratio of 4.5:1; the fluorosilicone block polyurethane acrylate oligomer is prepared according to the preparation method of photosensitive fluorosilicone block polyurethane acrylate oligomer in Example 3 of invention patent document CN102993404B; before use, the polymerization inhibitor is further removed by vacuum distillation.

[0036] The polythiol is polythiol 405; the photoinitiator is photoinitiator XBPO; the red pigment is pigment red 176; the blue pigment is pigment blue 15:3; the additives are antioxidants, light stabilizers, coupling agents, and catalysts compounded in a mass ratio of 1:1.1:1:0.45; the antioxidant is antioxidant 1010 and antioxidant 1076 compounded in a mass ratio of 1:2; the light stabilizer is light stabilizer 770 and light stabilizer 622 compounded in a mass ratio of 3:5; the coupling agent is silane coupling agent KH550, silane coupling agent KH560, and silane coupling agent KH570 compounded in a mass ratio of 1:1.1:1:0.45. The mixture is formulated with a mass ratio of 1:2:3; the catalyst is dibutyltin dilaurate; the functional additive is a compound of nano-zirconia and nano-zinc sulfide with a mass ratio of 1:0.9; the particle size of the functional additive is 90 nm; the active diluent is a mixture of monofunctional and difunctional diluents with a mass ratio of 1:1.7; wherein the monofunctional diluent is a compound of dicyclopentyl methacrylate and isobornyl methacrylate with a mass ratio of 1:2; and the difunctional diluent is a compound of tripropylene glycol diacrylate and 1,6-hexanediol diacrylate with a mass ratio of 3:5.

[0037] A method for preparing a polyurethane-based photocurable resin lens includes the following steps: mixing the components uniformly according to their weight proportions, vacuum degassing, injecting the mixture into an optical lens mold, and curing under a nitrogen protective atmosphere using an ultraviolet light curing device to obtain a pre-shaped lens; then performing a post-curing treatment, cooling to room temperature, and trimming and cleaning to obtain the polyurethane-based photocurable resin lens; wherein the ultraviolet light wavelength for ultraviolet light curing is 395 nm, and the light intensity is 70 mW / cm². 2 The curing time is 110s; the post-curing temperature is 65℃ and the time is 2.5h; the vacuum degree of the vacuum degassing is -0.095MPa and the degassing time is 18min. Example 5

[0038] A polyurethane-based photocurable resin lens is prepared from the following components in parts by weight: 40 parts of fluorosilicone block polyurethane acrylate oligomer, 20 parts of polythiol, 3 parts of photoinitiator, 0.1 parts of red pigment, 0.1 parts of blue pigment, 3 parts of additives, 2.5 parts of functional additives, 30 parts of reactive diluent, and 8 parts of other monomers; wherein the other monomers are 1,6-hexanediisocyanate and 3,9-divinyl-2,4,8,10-tetraoxaspiro[5.5]undecane compounded in a mass ratio of 5:1; the fluorosilicone block polyurethane acrylate oligomer is prepared according to the preparation method of photosensitive fluorosilicone block polyurethane acrylate oligomer in Example 3 of invention patent document CN102993404B; before use, the polymerization inhibitor is further removed by vacuum distillation.

[0039] The polythiol is polythiol 405; the photoinitiator is photoinitiator 819; the red pigment is pigment red 176; the blue pigment is pigment blue 15:3; the additives are antioxidants, light stabilizers, coupling agents, and catalysts compounded in a mass ratio of 1:1.2:1:0.5; the antioxidant is antioxidant 1010; the light stabilizer is light stabilizer 770; the coupling agent is silane coupling agent KH550; the catalyst is dibutyltin dilaurate; the functional additives are nano-sized... The compound of zirconium oxide and nano zinc sulfide is compounded in a mass ratio of 1:1.0; the particle size of the functional additives is 100 nm; the active diluent is a mixture of monofunctional and difunctional diluents in a mass ratio of 1:1.8; wherein the monofunctional diluent is a compound of dicyclopentyl methacrylate and isobornyl methacrylate in a mass ratio of 1:2; and the difunctional diluent is a compound of tripropylene glycol diacrylate and 1,6-hexanediol diacrylate in a mass ratio of 1:1.

[0040] A method for preparing a polyurethane-based photocurable resin lens includes the following steps: mixing the components evenly according to their weight proportions, vacuum degassing, injecting the mixture into an optical lens mold, and curing under a nitrogen protective atmosphere using an ultraviolet light curing device to obtain a pre-shaped lens; then performing a post-curing treatment, cooling to room temperature, and trimming and cleaning to obtain the polyurethane-based photocurable resin lens; wherein the ultraviolet light wavelength for ultraviolet light curing is 405 nm, and the light intensity is 80 mW / cm². 2 The curing time is 120s; the post-curing temperature is 70℃ and the time is 3h; the vacuum degree of the vacuum degassing is -0.10MPa and the degassing time is 20min.

[0041] Comparative Example 1 A polyurethane-based photocurable resin lens and its preparation method are basically the same as those in Example 5, except that an equal amount of 1,6-hexanediisocyanate is used instead of 3,9-divinyl-2,4,8,10-tetraoxaspiro[5.5]undecane.

[0042] Comparative Example 2 A polyurethane-based photocurable resin lens and its preparation method are basically the same as those in Example 5, except that an equal amount of 3,9-divinyl-2,4,8,10-tetraoxaspiro[5.5]undecane is used instead of 1,6-hexanediisocyanate.

[0043] Comparative Example 3 A polyurethane-based photocurable resin lens and its preparation method are basically the same as those in Example 5, except that an equal amount of fluorosilicone block polyurethane acrylate oligomer is used instead of polythiol.

[0044] Comparative Example 4 A polyurethane-based photocurable resin lens and its preparation method are basically the same as those in Example 5, except that an equal amount of nano-zirconia is used instead of nano-zinc sulfide.

[0045] Comparative Example 5 A polyurethane-based photocurable resin lens and its preparation method are basically the same as those in Example 5, except that an equal amount of nano zinc sulfide is used instead of nano zirconium oxide.

[0046] The polyurethane-based photocurable resin lenses of Examples 5 and Comparative Examples 1-5 were subjected to relevant performance tests using the following experimental methods. The test results are shown in Table 1: (1) Refractive index test: Refer to QB / T 2506-2017 "Spectacle Lenses Optical Resin Lenses", use Abbe refractometer to test the refractive index of the lens at 587.56nm (nitrogen yellow line d). Three points are tested for each sample, and the average value is taken with a tolerance of ±0.005. (2) Dispersion coefficient (Abbe number) test: Refer to QB / T 2506-2017 "Spectacular Lenses - Optical Resin Lenses", calculate the dispersion coefficient based on the refractive index test results, with a tolerance of ±5%; (3) Impact resistance test: The industry-standard falling ball impact test method is adopted. A 16g steel ball is dropped freely from a height of 1.2m and impacts the center of the lens. Five lenses are tested for each sample, and the number of qualified lenses is recorded (no breakage or cracks are considered qualified). (4) Yellowing resistance test: Refer to the light irradiation test method specified in the industry standard QB / T 2506-2017 "Spectacular Lenses Optical Resin Lenses", place the lens in a xenon lamp aging test chamber to simulate the natural light environment and irradiate for 1000h. Test the yellowness value (YI) of the lens before and after aging, and calculate the yellowness change rate (ΔYI). The smaller the ΔYI, the better the yellowing resistance.

[0047] Table 1 Performance test results of polyurethane-based photocurable resin lenses As can be seen from the data in Table 1, Example 5, by using a specific compound monomer, polythiol, and a compound functional additive of nano-zirconia and nano-zinc sulfide, yielded polyurethane-based photocurable resin lenses with significantly superior overall performance. The refractive index reached 1.635, the dispersion coefficient was 40, all impact resistance tests were passed, and the yellowing rate was only 0.5, demonstrating excellent resistance to yellowing. Comparative Examples 1 and 2, by using a single monomer to replace the compound monomer, showed significant decreases in refractive index, dispersion coefficient, and impact resistance, while the yellowing rate increased substantially. Comparative Example 3 used fluorosilicone block copolymer... Replacing polythiol with urethane acrylate oligomers significantly reduced the refractive index to 1.572, resulting in a substantial deterioration in impact resistance; only one piece passed the test, and the yellowing rate increased to 3.0. Comparative Examples 4 and 5 used single nano-zirconia and single nano-zinc sulfide, respectively, to replace the composite nanofillers. The refractive index and dispersion coefficient were lower than those of Example 5, the number of pieces passing the impact resistance test decreased, and the yellowing rate increased significantly. This indicates that the composite of key components in this technical solution has a significant synergistic effect, which can simultaneously achieve high refractive index, suitable dispersion, excellent impact resistance, and high resistance to yellowing.

[0048] The above embodiments are only for illustrating the technical concept and features of the present invention. Their purpose is to enable those skilled in the art to understand the content of the present invention and implement it accordingly. They should not be used to limit the scope of protection of the present invention. Any modifications, equivalent substitutions and improvements made within the spirit and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A polyurethane-based photocurable resin lens, characterized in that it is prepared from the following components in parts by weight: 30-40 parts of fluorosilicone block polyurethane acrylate oligomer, 10-20 parts of polythiol, 1-3 parts of photoinitiator, 0.05-0.1 parts of red pigment, 0.05-0.1 parts of blue pigment, 1-3 parts of additives, 0.5-2.5 parts of functional additives, 20-30 parts of reactive diluent, and 5-8 parts of other monomers; wherein the other monomers are 1,6-hexamethylene diisocyanate and 3,9-divinyl-2,4,8,10-tetraoxaziro[5.5]undecane compounded in a mass ratio of (3-5):

1.

2. The polyurethane-based photocurable resin lens according to claim 1, characterized in that, The polythiol is polythiol 405; the photoinitiator is at least one of photoinitiator 819 and photoinitiator XBPO.

3. The polyurethane-based photocurable resin lens according to claim 1, characterized in that, The red pigment is Pigment Red 176; the blue pigment is Pigment Blue 15:

3.

4. The polyurethane-based photocurable resin lens according to claim 1, characterized in that, The additives are antioxidants, light stabilizers, coupling agents, and catalysts compounded in a mass ratio of 1:(0.8-1.2):1:(0.3-0.5).

5. The polyurethane-based photocurable resin lens according to claim 4, characterized in that, The antioxidant is at least one of antioxidant 1010 and antioxidant 1076; the light stabilizer is at least one of light stabilizer 770 and light stabilizer 622; the coupling agent is at least one of silane coupling agent KH550, silane coupling agent KH560 and silane coupling agent KH570; and the catalyst is dibutyltin dilaurate.

6. The polyurethane-based photocurable resin lens according to claim 1, characterized in that, The functional additive is a compound of nano-zirconia and nano-zinc sulfide, with a mass ratio of 1:(0.6-1.0); the particle size of the functional additive is 50-100nm.

7. The polyurethane-based photocurable resin lens according to claim 1, characterized in that, The active diluent is a mixture of a monofunctional diluent and a difunctional diluent at a mass ratio of 1:(1.2-1.8); wherein the monofunctional diluent is selected from at least one of dicyclopentyl methacrylate and isobornyl methacrylate; and the difunctional diluent is selected from at least one of tripropylene glycol diacrylate and 1,6-hexanediol diacrylate.

8. A method for preparing a polyurethane-based photocurable resin lens according to any one of claims 1-7, characterized in that, The process includes the following steps: after mixing each component evenly according to the weight parts, vacuum degassing is performed, and the mixture is injected into an optical lens mold. Under a nitrogen protective atmosphere, ultraviolet light is used to irradiate and cure the mixture to obtain a preliminary shaped lens. Then, post-curing treatment is performed, and after cooling to room temperature, the lens is trimmed and cleaned to obtain the polyurethane-based photocurable resin lens.

9. The method for preparing a polyurethane-based photocurable resin lens according to claim 8, characterized in that, The ultraviolet light used for curing by ultraviolet irradiation has a wavelength of 365–405 nm and a light intensity of 20–80 mW / cm². 2 The curing time is 30-120 seconds; the post-curing treatment temperature is 50-70℃ and the time is 1-3 hours.

10. The method for preparing a polyurethane-based photocurable resin lens according to claim 8, characterized in that, The vacuum degree of the vacuum degassing is -0.08 to -0.10 MPa, and the degassing time is 10 to 20 minutes.

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