A fully chalcogenide optical resin lens and its preparation method

Abstract

This invention discloses a fully sulfur-based optical resin lens and its preparation method, belonging to the field of optical resin material technology. The lens is composed of a polymerizable composition comprising four fully sulfur-based monomers: bis(β-cyclothiopropyl)trisulfide, 2,6-di-tert-butylnaphthalene-1,5-diallyl sulfide, tri(β-cyclothiopropyl)isocyanurate, and bis(β-cyclothiopropyl)disulfide, as well as an organically modified layered double metal hydroxide, zinc dithiocarbamate, dilauryl thiodipropionate, hindered amine light stabilizer, phosphite antioxidant, tetraethyl orthosilicate, and an initiator, which is cured by synergistic anionic ring-opening polymerization and free radical polymerization. By adjusting the ratio of the four monomers, a continuously adjustable refractive index from 1.59 to 1.74 can be achieved within a single all-chalcogenide chemical system. Simultaneously, the Abbe number is no less than 40 and the light transmittance is no less than 96% in the refractive index range of 1.59 to 1.60; the Abbe number is no less than 35 and the light transmittance is no less than 95% in the refractive index range of 1.66 to 1.68; and the Abbe number is no less than 33 and the light transmittance is no less than 95% in the refractive index range of 1.73 to 1.74. The color difference ΔE of the lenses after baking at 180 degrees Celsius for 72 hours is no greater than 0.85. All raw materials are free of rare or toxic elements such as selenium, tellurium, and tin, ensuring a safe and environmentally friendly supply chain.

Description

Technical Field

[0001] This invention belongs to the field of optical resin material technology, specifically relating to an optical resin lens with a full chalcogenide monomer matrix and its preparation method. The lens can be flexibly controlled within the refractive index range of 1.59 to 1.74 by adjusting the ratio of the four monomers, while also possessing high light transmittance, high Abbe number and excellent heat resistance stability. Background Technology

[0002] In the field of optical resin lenses, the priorities for lens performance differ fundamentally depending on the degree of refractive error. For low myopia (below 300 degrees), wearers are less sensitive to lens thickness and more sensitive to visual quality, thus focusing more on Abbe number and light transmittance. For moderate to high myopia (300 to 800 degrees), wearers need to strike a balance between lens thickness and visual quality. For high myopia (above 800 degrees), lens thickness becomes the primary concern, with the aesthetic improvement resulting from thinner lenses receiving the highest priority. This differentiated demand necessitates customized performance combinations for optical resin lenses across different refractive index ranges.

[0003] In existing technologies, achieving lenses with different refractive indices typically relies on different chemical systems. Lenses with refractive indices of 1.50 to 1.56 are mostly based on allyl carbonate or acrylate systems, lenses with refractive indices of 1.60 to 1.67 mostly use polyurethane or polysulfide systems, while lenses with a refractive index of 1.74 almost entirely depend on polyurethane systems containing selenium, tellurium, or high thiol content. Switching between different chemical systems means completely different monomer supply chains, polymerization processes, and quality control standards. Manufacturers need to maintain multiple independent production lines, significantly increasing production complexity and costs.

[0004] More importantly, existing high-refractive-index systems often sacrifice Abbe number and light transmittance in pursuit of high refractive index. Polyurethane lenses with a refractive index of 1.74 typically have an Abbe number of only 28 to 30, resulting in significant dispersion, which some sensitive wearers may perceive at the edges. While high-refractive-index systems containing selenium or tellurium can push the refractive index above 1.75, they involve highly toxic gases and rare elements, making the supply chain fragile and posing high safety risks. Systems containing organotin are subject to strict environmental regulations.

[0005] Therefore, there is an urgent need to develop a method for preparing optical resin lenses that can flexibly cover the refractive index range of 1.59 to 1.74 within a single chemical system through fine-tuning of the formulation, while maintaining high Abbe number, high light transmittance and excellent heat resistance in each refractive index range. Summary of the Invention

[0006] The technical problem to be solved by this invention is: addressing the dual dilemma in existing optical resin lens technology where different refractive indices rely on different chemical systems, and high refractive indices are difficult to simultaneously achieve high Abbe numbers and high light transmittance. This invention provides an optical resin lens and its preparation method that are entirely based on sulfur and hydrocarbon elements, and can cover the refractive index range of 1.59 to 1.74 by adjusting the ratio of four monomers. This results in Abbe numbers of no less than 40 and light transmittance of no less than 96% in the refractive index range of 1.59 to 1.60, no less than 35 and light transmittance of no less than 95% in the refractive index range of 1.66 to 1.68, and no less than 33 and light transmittance of no less than 95% in the refractive index range of 1.73 to 1.74. Furthermore, the color difference ΔE of all three types of lenses after baking at 180 degrees Celsius for 72 hours is no greater than 0.85.

[0007] To solve the above-mentioned technical problems, the present invention adopts the following technical solution: A fully chalcogenide optical resin lens, which is formed by the synergistic curing of a polymerizable composition comprising the following components through anionic ring-opening polymerization and free radical polymerization: 23.00 to 52.00 parts by weight of bis-(β-cyclothiopropyl)trisulfide; 7.00 to 21.00 parts of 2,6-di-tert-butylnaphthalene-1,5-diallyl sulfide; Tri-(β-cyclothiopropyl)isocyanurate 16.00 to 44.00 parts; 10.00 to 27.00 parts of bis-(β-cyclothiopropyl) disulfide; 0.09 to 0.18 parts of organically modified layered bimetallic hydroxide; 0.04 to 0.10 parts of zinc dithiocarbamate; 0.02 to 0.06 parts of dilauryl thiodipropionate; 0.02 to 0.04 parts of hindered amine light stabilizer; Phosphite antioxidant, 0.02 to 0.04 parts; 0.020 to 0.040 parts of tetraethyl orthosilicate; Water 0.004 to 0.008 parts; 0.003 to 0.007 parts of alkaline catalyst; 0.15 to 0.25 parts of anionic polymerization initiator; 0.04 to 0.11 parts of free radical polymerization initiator.

[0008] The ratio of the four monomers determines the refractive index of the final lens. The trisulfide bonds of bis-(β-cyclothiopropyl)trisulfide provide high sulfur density and are the main contributor to the refractive index; its dosage is low in low-refractive-index schemes and high in high-refractive-index schemes. The naphthalene ring of 2,6-di-tert-butylnaphthalene-1,5-diallyl sulfide provides additional polarizability; its dosage increases or decreases in tandem with the target refractive index. The isocyanurate ring of tri-(β-cyclothiopropyl)isocyanurate provides a low-dispersion framework; its dosage is high in low-refractive-index schemes to increase the Abbe number and low in high-refractive-index schemes to avoid diluting the refractive index. The disulfide bonds of bis-(β-cyclothiopropyl)disulfide provide crosslinking sites and supplement sulfur density.

[0009] By adjusting the relative proportions of the four monomers mentioned above, a continuously adjustable refractive index from 1.59 to 1.74 can be achieved within the same chemical system, while maintaining a high Abbe number and high light transmittance across all refractive index ranges. This "one system, multiple products" strategy allows manufacturers to flexibly produce lenses with different refractive indices on the same production line by switching formulations, without the need to maintain multiple independent production lines.

[0010] Furthermore, when the target refractive index is 1.59 to 1.60 and the Abbe number is not less than 40, the proportions are as follows: 23.00 to 27.00 parts of bis-(β-cyclothiopropyl)trisulfide, 7.00 to 9.00 parts of 2,6-di-tert-butylnaphthalene-1,5-diallyl sulfide, 40.00 to 44.00 parts of tri-(β-cyclothiopropyl)isocyanurate, and 23.00 to 27.00 parts of bis-(β-cyclothiopropyl)disulfide. The high proportion of isocyanurate ensures the adequacy of the low-dispersion framework, pushing the Abbe number above 40.

[0011] When the target refractive index is 1.66 to 1.68 and the Abbe number is not less than 35, the composition is as follows: 36.00 to 40.00 parts of bis-(β-cyclothiopropyl)trisulfide, 13.00 to 15.00 parts of 2,6-di-tert-butylnaphthalene-1,5-diallyl sulfide, 28.00 to 32.00 parts of tri-(β-cyclothiopropyl)isocyanurate, and 16.00 to 20.00 parts of bis-(β-cyclothiopropyl)disulfide. A moderate increase in the content of trisulfide bonds and naphthalene rings raises the refractive index, while isocyanurate maintains a sufficient proportion to keep the Abbe number above 35.

[0012] When the target refractive index is 1.73 to 1.74 and the Abbe number is not less than 33, the composition is as follows: 48.00 to 52.00 parts of bis-(β-cyclothiopropyl)trisulfide, 19.00 to 21.00 parts of 2,6-di-tert-butylnaphthalene-1,5-diallyl sulfide, 16.00 to 20.00 parts of tri-(β-cyclothiopropyl)isocyanurate, and 10.00 to 14.00 parts of bis-(β-cyclothiopropyl)disulfide. The trisulfide and naphthalene ring contents reach their maximum to push the refractive index to the 1.74 level, while the isocyanurate content, although reduced to a minimum, is still sufficient to maintain an Abbe number above 33.

[0013] The organically modified layered bimetallic hydroxide is obtained by organic modification of magnesium-aluminum layered bimetallic hydroxide through sodium stearate intercalation, with a magnesium-aluminum molar ratio of 2:1 and an interlayer spacing of not less than 2.5 nm. The zinc dithiocarbamate irreversibly quenches sulfur free radicals into non-radical products through its zinc ion coordination structure. The above components, together with dilauryl thiodipropionate, hindered amine light stabilizer, and phosphite antioxidant, constitute a quadruple synergistic anti-yellowing system, acting on four nodes: metal catalytic passivation, sulfur free radical quenching, hydroperoxide decomposition, and alkyl free radical capture.

[0014] The present invention also provides a method for preparing the above-mentioned optical resin lens, comprising the following steps: Step 1: Prepare an anionic polymerization initiator solution in an inert atmosphere glove box; Step 2: In an inert atmosphere reactor, the four monomers are mixed in the required proportions for the target refractive index, and tetraethyl orthosilicate, water and alkaline catalyst are added. The mixture is stirred at 35°C (plus or minus 2 degrees Celsius) for 3 hours to obtain a monomer pretreatment solution containing in-situ nano silica dots. Step 3: Under inert atmosphere and vacuum conditions, the pretreatment liquid is mixed evenly with free radical polymerization initiator, hindered amine light stabilizer, phosphite antioxidant, and dilauryl thiodipropionate. Then, zinc dithiocarbamate and organic modified layered bimetallic hydroxide are added and dispersed with ultrasonic field assistance. Step four: The mixed slurry is pressure filtered through a microporous membrane with a pore size of 0.2 micrometers and degassed under vacuum conditions; Step 5: Pour the degassed slurry into a glass mold, inject anionic polymerization initiator solution into the casting head, and complete the polymerization according to the gradient thermosetting procedure; Step six: Anneal the cured lens along with the mold according to the gradient annealing procedure. After demolding, perform UV field post-curing and microwave field stress relief. After cleaning, the lens is obtained.

[0015] Compared with the prior art, the beneficial effects of the present invention are as follows: Firstly, a continuously adjustable refractive index from 1.59 to 1.74 is achieved within a single all-chalcogenide chemical system. All four monomers are all-chalcogenide or sulfur-carbon-hydrogen compounds, free of any toxic heavy metals or rare elements such as selenium, tellurium, tin, and lead. Manufacturers can flexibly produce lenses with different refractive indices on the same production line by adjusting the ratio of the four monomers, significantly reducing equipment investment, supply chain complexity, and switching costs for multiple product lines.

[0016] Secondly, it achieves Abbe numbers higher than existing technologies in the same class across all refractive index ranges. The low refractive index solution achieves an Abbe number of over 40, comparable to CR-39; the medium refractive index solution achieves an Abbe number of over 35, superior to polyurethane lenses in the same class; and the high refractive index solution achieves an Abbe number of over 33, leading the way in the 1.74 refractive index category. A high Abbe number means low dispersion, meaning the wearer will not perceive dispersion in the central visual field.

[0017] Third, it maintains high light transmittance across all refractive index ranges. The low refractive index scheme has a light transmittance of no less than 96%, and the medium-to-high refractive index scheme has a light transmittance of no less than 95%, both superior to existing mainstream products at the same refractive index level. High light transmittance ensures ample brightness reserves in indoor lighting and low-light environments.

[0018] Fourth, all three lenses share the same quadruple synergistic anti-yellowing system. Organically modified layered bimetallic hydroxides passivate the metal catalyst and block oxygen diffusion; zinc dithiocarbamate irreversibly quenches sulfur free radicals; dilauryl thiodipropionate decomposes hydrogen peroxide; and hindered amine light stabilizers and phosphite antioxidants block the propagation of the oxidation chain reaction. This quadruple mechanism covers the entire pathway of high-temperature oxidation of sulfides, ensuring that the color difference ΔE of all three lenses is controlled below 0.85 after 72 hours of extreme baking at 180 degrees Celsius.

[0019] In summary, this invention, through precise molecular optical design and flexible control of quaternary monomer ratios, has for the first time achieved optical resin lenses covering the refractive index range of 1.59 to 1.74 within a single all-chalcogenide chemical system, while maintaining high Abbe numbers, high light transmittance, and excellent heat resistance in each range. This provides a novel systematic solution for the efficient production of a variety of optical resin lenses. Detailed Implementation

[0020] The technical solution of the present invention will be described in detail below through nine embodiments and several comparative examples, but the scope of protection of the present invention is not limited thereto. Example

[0021] A potassium n-butylthiol solution was prepared in an inert atmosphere glove box, and its concentration was standardized to 0.50 mol / L by hydrochloric acid titration. The water content was determined to be 42 ppm by Karl Fischer method. The solution was then sealed and stored in a stainless steel container with a molecular sieve adsorption layer for later use. Azobisisobutyronitrile was recrystallized twice with anhydrous ethanol, dried under vacuum to constant weight, and stored in a sealed, light-protected environment at 4°C.

[0022] 25.00 parts of bis-(β-cyclothiopropyl) trisulfide, 8.00 parts of 2,6-di-tert-butylnaphthalene-1,5-diallyl sulfide, 42.00 parts of tri-(β-cyclothiopropyl) isocyanurate, and 25.00 parts of bis-(β-cyclothiopropyl) disulfide were added to a jacketed, temperature-controlled glass reactor. At room temperature, 0.030 parts of tetraethyl orthosilicate, 0.006 parts of deionized water, and 0.005 parts of ammonia were added sequentially. The reactor was sealed and evacuated to 150 Pascals, then purged with high-purity nitrogen to atmospheric pressure, and this process was repeated three times. Under nitrogen protection, the mixture was stirred at 180 rpm and heated to 35°C, and the reaction was maintained at this temperature for 3 hours. Dynamic light scattering analysis showed that the hydrated particle size (D90) of the nanoparticles in the system was 7.5 nm.

[0023] The pretreated solution was transferred to a planetary vacuum mixer, and under nitrogen protection, 0.06 parts of azobisisobutyronitrile (AIBN), 0.03 parts of hindered amine light stabilizer, 0.03 parts of phosphite antioxidant, and 0.04 parts of dilauryl thiodipropionate were added. The mixture was then sealed and evacuated to 80 Pa, and stirred at 35 revolutions per minute and 70 rotations per minute for 40 minutes until completely dissolved. Subsequently, under nitrogen protection, 0.06 parts of zinc dithiocarbamate and 0.12 parts of organically modified layered bimetallic hydroxide were added. X-ray diffraction confirmed that the layered bimetallic hydroxide had an interlayer spacing of 2.7 nm, a magnesium-to-aluminum ratio of 2:1, a median particle size (D50) of 115 nm, and a total iron-nickel-vanadium content of 4.3 ppm. The mixture was then evacuated to 80 Pa and stirred at 20 revolutions per minute and 40 rotations per minute for 20 minutes.

[0024] The premixed slurry was transferred to an ultrasonic liquid dispersion system and treated for 12 minutes at a frequency of 40 kHz and a power density of 50 W / L, with jacket cooling to keep the material temperature no higher than 28 degrees Celsius.

[0025] The slurry was pressurized by 0.3 MPa high-purity nitrogen gas and passed through a 0.2-micron pore size polytetrafluoroethylene membrane. The filtrate was then transferred to a vacuum degassing machine and degassed at 15 revolutions per minute under a 40 Pa vacuum for 50 minutes.

[0026] After degassing, the slurry is injected into a borosilicate glass mold with an inner surface roughness Ra of 0.015 micrometers via an automatic casting machine. A potassium n-butyl mercaptan solution is injected into the casting head at a rate of 0.18 parts (based on pure potassium n-butyl mercaptan), mixed online, and then fed into the mold. The mold is placed in a six-stage gradient curing oven: 50°C for 30 minutes, 70°C for 40 minutes, 88°C for 25 minutes, 100°C for 20 minutes, 110°C for 15 minutes, and 80°C for 10 minutes. It is then placed in a five-stage gradient annealing furnace: 95°C for 16 minutes, 80°C for 16 minutes, 65°C for 16 minutes, and 50°C for 16 minutes, cooling to 30°C at a rate of 1.8°C per minute.

[0027] After annealing, the lens is demolded. It is then irradiated with a 365nm LED array light source for 5 minutes at a light intensity of 100 milliwatts per square centimeter. Next, it is microwaved at 2450 MHz until the lens surface temperature reaches 45 degrees Celsius for approximately 3 minutes. Finally, it is ultrasonically cleaned in 40 kHz deionized water at 40 degrees Celsius for 5 minutes and then dried.

[0028] The refractive index nD² of the obtained lens was measured using an Abbe refractometer. 0 =1.597; the integrated transmittance of visible light, as measured by an integrating sphere spectrophotometer, is 96.8%; the Abbe number νd is 41.5; the root mean square value of the birefringence path difference, as measured by a polarimeter, is 10 nm; after being dried in an oven at 180 degrees Celsius for 72 hours, ΔE, as measured by a CIELAB colorimeter, is 0.72; the residual monomer content, as determined by differential scanning calorimetry, is 0.35%. This lens is suitable for myopia ranging from 200 to 400 degrees. Example

[0029] The difference from Example 1 is that the amounts of bis-(β-cyclothiopropyl) trisulfide were adjusted to 38.00 parts, 2,6-di-tert-butylnaphthalene-1,5-diallyl sulfide to 14.00 parts, tri-(β-cyclothiopropyl) isocyanurate to 30.00 parts, bis-(β-cyclothiopropyl) disulfide to 18.00 parts, azobisisobutyronitrile to 0.08 parts, potassium n-butylthiolate to 0.20 parts, organically modified layered bimetallic hydroxide to 0.12 parts, and zinc dithiocarbamate to 0.06 parts; the gradient curing program was adjusted to 50°C for 35 minutes, 70°C for 42 minutes, 90°C for 28 minutes, 105°C for 22 minutes, 112°C for 15 minutes, and 80°C for 10 minutes. All other conditions remained unchanged.

[0030] The resulting lens has a refractive index of 1.667, a light transmittance of 95.5%, an Abbe number of 35.8, a birefringence RMS of 12 nm, a baking ΔE of 0.75, and a residual monomer content of 0.38%. This lens is suitable for myopia ranging from 400 to 800 degrees. Example

[0031] The difference from Example 1 is that the amounts of bis-(β-cyclothiopropyl) trisulfide were adjusted to 50.00 parts, 2,6-di-tert-butylnaphthalene-1,5-diallyl sulfide to 20.00 parts, tri-(β-cyclothiopropyl) isocyanurate to 18.00 parts, bis-(β-cyclothiopropyl) disulfide to 12.00 parts, azobisisobutyronitrile to 0.09 parts, potassium n-butylthiol to 0.22 parts, organically modified layered bimetallic hydroxide to 0.15 parts, and zinc dithiocarbamate to 0.08 parts; the gradient curing program was adjusted to 50°C for 35 minutes, 70°C for 45 minutes, 90°C for 30 minutes, 105°C for 25 minutes, 115°C for 15 minutes, and 80°C for 10 minutes. All other conditions remained unchanged.

[0032] The resulting lens has a refractive index of 1.738, a light transmittance of 95.8%, an Abbe number of 33.2, a birefringence RMS of 13 nm, a baking ΔE of 0.78, and a residual monomer content of 0.40%. This lens is suitable for myopia ranging from 800 to 1200 degrees. Example

[0033] Based on the low refractive index scheme of Example 1, the tri-(β-cyclothiopropyl) isocyanurate was adjusted to 44.00 parts, the bis-(β-cyclothiopropyl) disulfide was adjusted to 23.00 parts, and other conditions remained unchanged.

[0034] The resulting lens has a refractive index of 1.593, a light transmittance of 97.0%, an Abbe number of 42.0, a birefringence RMS of 9 nm, and a baking ΔE of 0.70. Further increasing the isocyanate content increases the Abbe number to 42, but the refractive index slightly decreases to 1.593, still within the target range. Example

[0035] Based on the refractive index scheme in Example 2, the amounts of bis-(β-cyclothiopropyl) trisulfide were adjusted to 40.00 parts, 2,6-di-tert-butylnaphthalene-1,5-diallyl sulfide to 15.00 parts, tri-(β-cyclothiopropyl) isocyanurate to 28.00 parts, and bis-(β-cyclothiopropyl) disulfide to 17.00 parts, while other conditions remained unchanged.

[0036] The resulting lens has a refractive index of 1.672, a light transmittance of 95.3%, an Abbe number of 35.2, a birefringence RMS of 13 nm, and a baking ΔE of 0.77. The refractive index increased slightly but still met the requirements, and the Abbe number decreased slightly but remained above 35. Example

[0037] Based on the high refractive index scheme of Example 3, the amount of bis-(β-cyclothiopropyl) trisulfide was adjusted to 52.00 parts, the amount of bis-(β-cyclothiopropyl) disulfide was adjusted to 10.00 parts, and other conditions remained unchanged.

[0038] The resulting lens has a refractive index of 1.741, a light transmittance of 95.2%, an Abbe number of 32.9, a birefringence RMS of 14 nm, and a baking ΔE of 0.80. The refractive index was pushed to the upper limit, and the Abbe number was slightly below 33 but still within the allowable fluctuation range. Example

[0039] Based on the refractive index scheme in Example 2, the potassium n-butylthiolate was adjusted to 0.23 parts, the azobisisobutyronitrile was adjusted to 0.10 parts, the temperature of the fourth stage of the gradient curing program was adjusted to 108 degrees Celsius, and other conditions remained unchanged.

[0040] The resulting lens has a refractive index of 1.669, a light transmittance of 95.4%, an Abbe number of 35.6, a birefringence RMS of 13 nm, a baking ΔE of 0.78, and a residual monomer content of 0.35%. Even after minor adjustments to the initiator dosage and curing temperature, the performance remained fully satisfactory. Example

[0041] The same formulation and process as in Example 1 were used, but the UV light field and microwave field post-treatment were omitted after annealing, and only the thermal annealing was retained.

[0042] The resulting lens had a light transmittance of 95.5%, a birefringence RMS of 13 nm, and a baking ΔE of 0.79. The light transmittance decreased by approximately 1.3 percentage points compared to Example 1, while the birefringence increased slightly, demonstrating the effectiveness of UV and microwave post-treatment in improving light transmittance and stress. Example

[0043] Based on the low refractive index scheme of Example 1, the zinc dithiocarbamate was adjusted to 0.10 parts, the dilauryl thiodipropionate was adjusted to 0.02 parts, and other conditions remained unchanged.

[0044] The resulting lens had a light transmittance of 96.6%, an Abbe number of 41.3, a birefringence RMS of 10 nm, and a baking ΔE of 0.68. The addition of zinc dithiocarbamate enhanced sulfur radical quenching, and baking further reduced color difference, demonstrating a complementary regulatory space between the anti-yellowing components.

[0045] Comparative Example 1 The difference from Example 3 is that bis-(β-cyclothiopropyl) trisulfide is not used, and 50.00 parts of it are replaced with an equal amount of bis-(β-cyclothiopropyl) sulfide, while other conditions remain unchanged.

[0046] The resulting lens had a refractive index of 1.685 and an Abbe number of 34.5. The absence of trisulfide bonds resulted in insufficient sulfur density, preventing the refractive index from reaching a level above 1.73, demonstrating the irreplaceable role of the trisulfide bond structure in achieving high refractive indices.

[0047] Comparative Example 2 The difference from Example 3 is that 2,6-di-tert-butylnaphthalene-1,5-diallyl sulfide is not used, and its 20.00 parts are replaced with an equal amount of bis-(β-cyclothiopropyl) disulfide, while other conditions remain unchanged.

[0048] The resulting lens had a refractive index of 1.720 and an Abbe number of 35.0. The high polarizability of the naphthalene ring was not utilized, resulting in the inability to achieve the desired refractive index, demonstrating the necessity of the naphthalene ring structure in the all-sulfur system to increase the refractive index.

[0049] Comparative Example 3 The difference from Example 1 is that tri-(β-cyclothiopropyl) isocyanurate is not used, and its 42.00 parts are replaced with an equal amount of bis-(β-cyclothiopropyl) sulfide, while other conditions remain unchanged.

[0050] The resulting lens had a refractive index of 1.605, but the Abbe number dropped to 34.2, far below the target of 40. The absence of the low-dispersion framework of the isocyanurate ring prevented the Abbe number from being maintained above 40, demonstrating the irreplaceable nature of this component for achieving a high Abbe number in the low refractive index scheme.

[0051] Comparative Example 4 The difference from Example 3 is that tri-(β-cyclothiopropyl)isocyanurate is not used, and its 18.00 parts are replaced with an equal amount of bis-(β-cyclothiopropyl) sulfide, while other conditions remain unchanged.

[0052] The resulting lens had a refractive index of 1.745, but the Abbe number dropped to 30.5. Since the isocyanate content was already extremely low, its complete removal prevented the Abbe number from remaining above 33, demonstrating that even in high-refractive-index schemes, the low-dispersion framework of isocyanate remains crucial for maintaining an Abbe number above 33.

[0053] Comparative Example 5 The difference from Example 1 is that zinc dithiocarbamate is not used, while other conditions remain the same.

[0054] The initial properties of the resulting lenses were comparable to those of Example 1, but ΔE increased to 1.55 after baking at 180°C for 72 hours. The loss of sulfur radical quenching function did not interrupt the chain initiation step of thioether oxidation, leading to worsened yellowing. This demonstrates that the core contribution of zinc dithiocarbamate to heat-resistant yellowing applies to all refractive index schemes.

[0055] Comparative Example 6 The difference from Example 3 is that the organically modified layered bimetallic hydroxide is not used, while other conditions remain the same.

[0056] The resulting lens had an initial transmittance of 95.9%, and the ΔE increased to 1.60 after baking. The absence of the layered bimetallic hydroxide did not inhibit metal-catalyzed oxidation, and yellowing was significantly exacerbated, demonstrating that the anti-yellowing function of this component is independent of changes in the refractive index scheme.

[0057] Comparative Example 7 The difference from Example 1 is that zinc dithiocarbamate and organically modified layered bimetallic hydroxide are not used at the same time, while other conditions remain the same.

[0058] The resulting lens exhibited a baking ΔE as high as 2.70. The loss of both sulfur radical quenching and metal passivation functions resulted in yellowing exceeding the sum of their individual losses, demonstrating a positive synergistic effect between the two, and that this synergistic effect is universal across the entire sulfur system.

[0059] Comparative Example 8 The difference from Example 2 is that ultrasonic field dispersion is not used; instead, conventional mechanical stirring is used to disperse the layered bimetallic hydroxide and zinc dithiocarbamate, while other conditions remain unchanged.

[0060] The initial transmittance of the resulting lens decreased to 93.8%, the birefringence RMS increased to 17 nm, and the baking ΔE was 1.15. Mechanical stirring could not fully exfoliate the layered bimetallic hydroxide into nanosheets, and the large number of stacked particles led to scattering and stress concentration, proving that ultrasonic field dispersion is irreplaceable for the uniform dispersion of nano-anti-yellowing components.

[0061] Comparative Example 9 The difference from Example 1 is that the curing process is a single temperature of 90 degrees Celsius for 120 minutes, while other conditions remain unchanged.

[0062] The resulting lens had a refractive index of 1.588, a light transmittance of 93.5%, a birefringence RMS of 22 nm, a residual monomer content as high as 1.60%, and a baking ΔE of 1.90. Single-temperature curing completely rendered the dual-initiation path sequential separation strategy ineffective. Anionic ring-opening polymerization and free radical polymerization competed disorderly at the same temperature, resulting in severely uneven crosslinking and a comprehensive deterioration of all indicators. This demonstrates the decisive role of the gradient thermosetting process in product quality.

[0063] As can be seen from the above embodiments and comparative examples, the quaternary monomer flexible formulation system, the four-fold synergistic anti-yellowing system, and the multi-segment gradient energy field synergistic process defined in this invention are closely related. The absence or substitution of any core feature will result in at least one of the following indicators failing to meet requirements: refractive index, transmittance, Abbe number, or baking color difference. Examples 1 to 9 comprehensively demonstrate that this technical solution can stably achieve high-performance indicators in a wide refractive index range of 1.59 to 1.74 through formula fine-tuning. Comparative Examples 1 to 9 systematically verified the necessity of each core feature and the critical significance of specific parameter ranges from nine perspectives: absence of trisulfide bonds, absence of naphthalene rings, absence of low-dispersion framework (low refractive index scheme), absence of low-dispersion framework (high refractive index scheme), absence of sulfur radical quenching, absence of metal passivation, simultaneous absence of dual functions, absence of ultrasonic field, and improper curing procedure.

[0064] Although embodiments of the present invention have been shown and described above, those skilled in the art can make various changes, modifications, substitutions and alterations to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the claims and their equivalents.

Claims

1. A fully chalcogenide optical resin lens, characterized in that, It is formed by the synergistic curing of a polymerizable composition comprising the following components through anionic ring-opening polymerization and free radical polymerization: By weight parts 23.00 to 52.00 parts of bis-(β-cyclothiopropyl)trisulfide; 7.00 to 21.00 parts of 2,6-di-tert-butylnaphthalene-1,5-diallyl sulfide; Tri-(β-cyclothiopropyl)isocyanurate 16.00 to 44.00 parts; 10.00 to 27.00 parts of bis-(β-cyclothiopropyl) disulfide; 0.09 to 0.18 parts of organically modified layered bimetallic hydroxide; 0.04 to 0.10 parts of zinc dithiocarbamate; 0.02 to 0.06 parts of dilauryl thiodipropionate; 0.02 to 0.04 parts of hindered amine light stabilizer; Phosphite antioxidant, 0.02 to 0.04 parts; 0.020 to 0.040 parts of tetraethyl orthosilicate; Water 0.004 to 0.008 parts; 0.003 to 0.007 parts of alkaline catalyst; 0.15 to 0.25 parts of anionic polymerization initiator; 0.04 to 0.11 parts of free radical polymerization initiator; All four monomers are all sulfur-based or sulfur-carbon-based compounds, and do not contain selenium, tellurium, tin, lead, mercury, cadmium, or halogen elements.

2. The all-chalcogenide optical resin lens according to claim 1, characterized in that, When the target refractive index is 1.59 to 1.60 and the Abbe number is not less than 40, the components are 23.00 to 27.00 parts of bis-(β-cyclothiopropyl) trisulfide, 7.00 to 9.00 parts of 2,6-di-tert-butylnaphthalene-1,5-diallyl sulfide, 40.00 to 44.00 parts of tri-(β-cyclothiopropyl) isocyanurate, and 23.00 to 27.00 parts of bis-(β-cyclothiopropyl) disulfide.

3. The all-chalcogenide optical resin lens according to claim 1, characterized in that, When the target refractive index is 1.66 to 1.68 and the Abbe number is not less than 35, the components are 36.00 to 40.00 parts of bis-(β-cyclothiopropyl) trisulfide, 13.00 to 15.00 parts of 2,6-di-tert-butylnaphthalene-1,5-diallyl sulfide, 28.00 to 32.00 parts of tri-(β-cyclothiopropyl) isocyanurate, and 16.00 to 20.00 parts of bis-(β-cyclothiopropyl) disulfide.

4. The all-chalcogenide optical resin lens according to claim 1, characterized in that, When the target refractive index is 1.73 to 1.74 and the Abbe number is not less than 33, the components are 48.00 to 52.00 parts of bis-(β-cyclothiopropyl) trisulfide, 19.00 to 21.00 parts of 2,6-di-tert-butylnaphthalene-1,5-diallyl sulfide, 16.00 to 20.00 parts of tri-(β-cyclothiopropyl) isocyanurate, and 10.00 to 14.00 parts of bis-(β-cyclothiopropyl) disulfide.

5. The all-chalcogenide optical resin lens according to claim 1, characterized in that, The organically modified layered bimetallic hydroxide is obtained by organic modification of magnesium-aluminum layered bimetallic hydroxide by intercalation with sodium stearate, with a magnesium-aluminum molar ratio of 2:1, an interlayer spacing of not less than 2.5 nanometers, a median particle size D50 of 80 to 150 nanometers, a specific surface area of ​​not less than 80 square meters per gram, and a total iron-nickel-vanadium content of not more than 5 ppm.

6. The all-chalcogenide optical resin lens according to claim 1, characterized in that, The zinc dithiocarbamate has a purity of not less than 98.0%, a median particle size (D50) of 1 to 3 micrometers, and a zinc content of 16.0% to 18.5%.

7. The all-chalcogenide optical resin lens according to claim 1, characterized in that, The anionic polymerization initiator is potassium n-butylthiol, the free radical polymerization initiator is azobisisobutyronitrile, and the alkaline catalyst is ammonia.

8. A method for preparing a full chalcogenide optical resin lens as described in any one of claims 1 to 7, characterized in that, Includes the following steps: Step 1: Prepare an anionic polymerization initiator solution in an inert atmosphere glove box, ensuring that the moisture content is not higher than 50 ppm; Step 2: In an inert atmosphere reactor, bis-(β-cyclothiopropyl) trisulfide, 2,6-di-tert-butylnaphthalene-1,5-diallyl sulfide, tri-(β-cyclothiopropyl) isocyanurate and bis-(β-cyclothiopropyl) disulfide are mixed in proportion, and tetraethyl orthosilicate, water and alkaline catalyst are added. The mixture is stirred at 35°C (plus or minus 2°C) for 2 to 4 hours to obtain a monomer pretreatment solution containing in-situ nano-silica dots. Step 3: Under inert atmosphere and vacuum conditions, the pretreatment liquid is mixed evenly with free radical polymerization initiator, hindered amine light stabilizer, phosphite antioxidant, and dilauryl thiodipropionate. Then, zinc dithiocarbamate and organic modified layered bimetallic hydroxide are added and dispersed with ultrasonic field assistance to obtain a mixed slurry. Step four: The mixed slurry is pressure filtered through a microporous membrane with a pore size of 0.2 micrometers and degassed under vacuum conditions; Step 5: Pour the degassed slurry into a glass mold, inject anionic polymerization initiator solution into the casting head, and complete the polymerization according to the gradient thermosetting procedure; Step six: Anneal the cured lens along with the mold according to the gradient annealing procedure. After demolding, perform UV field post-curing and microwave field stress relief. After cleaning, the lens is obtained.

9. The preparation method according to claim 8, characterized in that, The gradient thermosetting process employs a six-stage gradient temperature control: the first stage maintains 50 ± 1 degrees Celsius for 30 to 35 minutes; the second stage maintains 70 ± 1 degrees Celsius for 40 to 45 minutes; the third stage maintains 88 to 90 ± 1 degrees Celsius for 25 to 30 minutes; the fourth stage maintains 100 to 105 ± 1 degrees Celsius for 20 to 25 minutes; the fifth stage maintains 110 to 115 ± 1 degrees Celsius for 15 minutes; and the sixth stage maintains 80 ± 1 degrees Celsius for 10 minutes. The ultraviolet light field uses a 365 nm LED array light source with a light intensity of 100 ± 10 milliwatts per square centimeter and an irradiation time of 5 ± 2 minutes. The microwave field uses 2450 MHz industrial microwaves to process the lens surface until it reaches 45 ± 2 degrees Celsius, with a duration of 1 to 5 minutes.

10. The preparation method according to claim 8, characterized in that, The gradient annealing process employs a five-stage gradient temperature control: the first stage maintains 95 degrees Celsius plus or minus 1 degree Celsius for 16 to 18 minutes; the second stage maintains 80 degrees Celsius plus or minus 1 degree Celsius for 16 to 18 minutes; the third stage maintains 65 degrees Celsius plus or minus 1 degree Celsius for 16 to 18 minutes; the fourth stage maintains 50 degrees Celsius plus or minus 1 degree Celsius for 16 to 18 minutes; and the fifth stage cools to 30 degrees Celsius plus or minus 2 degrees Celsius at a rate not exceeding 2 degrees Celsius per minute.