Vacuum coating process for anti-blue-light anti-yellowing lens

Abstract

The invention discloses an anti-blue-light anti-yellowing lens and a vacuum coating process thereof, belongs to the technical field of optical lens manufacturing, and aims to solve the problems of fixed anti-blue-light rate, short anti-yellowing service life, non-environment-friendly process and poor film stability in the prior art. The process core comprises substrate pretreatment, air plasma activation, adhesion promotion layer deposition, dynamic blue light prevention layer deposition, MXene / MOF composite anti-yellowing layer deposition and post-treatment. The lens structurally comprises a base material, a plasma activation layer, a SiO2-ZrO2 adhesive force layer, a ZrO2-Al2O3-Y2O3-azobenzene dynamic blue light prevention layer and a Ti < 3 > C < 2 > T < X >-UiO-66 anti-yellowing layer from inside to outside. According to the invention, the barrier rate of 415-455nm blue light is dynamically adjusted; the air plasma replaces high-purity gas, the gas cost is reduced by 60%, carbon emission is reduced by 40%, and the air plasma is suitable for PC, CR-39 and glass substrates, can be widely applied to daily goggles, myopia glasses and other scenes and has remarkable technical and industrialization values.

Description

Technical Field

[0001] This invention belongs to the field of optical lens manufacturing technology, specifically, it relates to a vacuum coating process for anti-blue light and anti-yellowing lenses. Background Technology

[0002] With the widespread use of electronic devices, the harmful effects of blue light (especially in the 415-455nm wavelength range) on the human eye have become widely recognized, leading to a surge in demand for blue light blocking lenses. Meanwhile, the yellowing of lenses due to UV exposure and oxidation over long-term use severely impacts light transmittance and lifespan, representing a critical pain point that the industry urgently needs to address.

[0003] The existing technology has the following limitations: Fixed blue light blocking performance: Traditional lenses use a single-layer design with a fixed blue light blocking rate (usually 30%-40%), which cannot adapt to the difference in blue light intensity between indoors and outdoors (200-500μW / cm² indoors). 2 vs Outdoor 1000-2000μW / cm 2 This can lead to "severe indoor color distortion" or "insufficient outdoor protection".

[0004] Short anti-yellowing lifespan: It relies on a single antioxidant such as CeO2. After long-term ultraviolet irradiation, the antioxidant efficiency decreases. After 1000 hours of aging, the yellowing index Δb* often exceeds 1.5, which is especially obvious in resin substrates.

[0005] Poor environmental friendliness of the process: Coating relies on 99.999% high-purity Ar / O2, with gas costs accounting for more than 35%, and the preparation process has high carbon emissions; plasma activation can easily lead to excessive oxidation of the resin substrate.

[0006] Insufficient film adhesion: poor interlayer stress matching, easy to fall off under high temperature and high humidity environment, and the cross-cut test often only reaches level 1 (ISO 2409).

[0007] Therefore, developing a coating process that can dynamically adjust the blue light protection rate, provide long-lasting anti-yellowing, is environmentally friendly, and has high adhesion has significant industrial value. Summary of the Invention

[0008] In view of this, the technical problem to be solved by the present invention is to provide a vacuum coating process for anti-blue light and anti-yellowing lenses, so as to avoid the problem of poor anti-blue light and anti-yellowing effects of previous resin lenses.

[0009] To address the aforementioned technical problems, this invention discloses a vacuum coating process for anti-blue light and anti-yellowing lenses, comprising the following steps: Step S1: Substrate Pretreatment. This step aims to remove oil, release agent, and minute impurities from the substrate surface, providing a clean surface for subsequent coating. Specifically, it includes: Ultrasonic cleaning: Place the lens substrate (PC, CR-39, or glass) into an ultrasonic cleaning tank, use a neutral cleaning agent (pH 6.5-7.5, main component is fatty alcohol polyoxyethylene ether, concentration 2%), and ultrasonically clean for 10 minutes at 50℃ water temperature, ultrasonic power 300W, frequency 40kHz. These parameters ensure that grease-like impurities are fully removed under cavitation effect without damaging the substrate surface; Pure water rinsing: Transfer the cleaned substrate to a deionized water tank (resistivity ≥18MΩ・cm) and rinse three times, 2 minutes each time, to remove residual cleaning agent. The rinsing water temperature should be controlled at 40℃ to avoid sudden temperature changes that could cause stress release in the substrate. Hot air drying: The substrate surface is dried using clean hot air at 60℃ (wind speed 2m / s) for 5 minutes. During the drying process, the substrate surface temperature is monitored in real time using an infrared thermometer to ensure it does not exceed the heat distortion temperature of the resin substrate (120℃ for PC, 100℃ for CR-39). After drying, a contact angle meter is used to check that the residual water film on the substrate surface is ≤10mg / m², ensuring that no liquid residue will affect subsequent coating.

[0010] Step S2: Air Plasma Activation. This step modifies the substrate surface using plasma, introducing active groups such as hydroxyl (-OH) groups to improve film adhesion. The specific process is as follows: Vacuum chamber preparation: Fix the dried substrate onto the planetary rotating jig (5 rpm) to ensure uniform film thickness during coating. Close the vacuum chamber and use a mechanical pump to roughly evacuate to 5 × 10⁻⁶ mm. -2 Pa, then restart the molecular pump to precisely pump to 5 × 10 -4 Hold the pressure at 100 Pa for 30 minutes to remove any residual gas from the cavity; Air dehydration treatment: Before compressed air is introduced, it is first treated by a molecular sieve dehydration device (4A molecular sieve, regeneration temperature 300℃) to make the water content in the air ≤0.1ppm, so as to avoid water vapor causing bubbles or pinholes in the membrane layer; Plasma activation parameters: Adjust the airflow rate to 25-30 sccm (standard milliliters per minute), turn on the radio frequency (RF) power supply, set the power to 120W, and the processing time to 4 minutes. Under these parameters, O2 and N2 in the air are decomposed into O2. - OH - N2 + Active particles, of which O - / OH - Reaction with carbon chains on the substrate surface to form a hydroxylated layer, N2 + This forms a thin nitride layer (thickness ≤ 5 nm), which together increases the surface energy to ≥ 55 mN / m (water contact angle ≤ 30°).

[0011] Step S3: Adhesion Promotion Layer Deposition. This layer serves as a transition between the substrate and the functional layer, relieving interfacial stress and improving the overall film adhesion. Mid-frequency magnetron sputtering technology is employed, with the following specific parameters: Target material selection: SiO2-ZrO2 composite target (molar ratio 7:3), prepared by vacuum hot pressing sintering (sintering temperature 1200℃, pressure 5MPa), target material density ≥3.8g / cm³, size Φ100×5mm; Deposition conditions: Vacuum degree 2×10 -3 Pa, the deposition temperature is adjusted according to the substrate type (60-70℃ for resin substrates, 100℃ for glass substrates), the target power is 2.5kW, the deposition rate is 2-3nm / min, and the final film thickness is controlled at 50-80nm. Ion beam assisted deposition (IAD): The ion beam source is activated, energy is set to 100 eV, current to 20 mA, and Ar... + Ion bombardment of the film surface eliminates pores and promotes particle diffusion, thereby increasing the film density to ≥95%.

[0012] Step S4: Deposition of Dynamic Blue Light Blocking Layer. This layer achieves dynamic adjustment of the blue light blocking rate through photoresponsive materials. The core process is as follows: Target composition: ZrO2-Al2O3-Y2O3-azobenzene derivative composite target, wherein the molar ratio of ZrO2, Al2O3, and Y2O3 is 5:4:1, and the azobenzene derivative (4-hydroxyazobenzene) accounts for 5%. The target is prepared using a spray granulation-sintering process (sintering temperature 1100℃) to ensure uniform dispersion of azobenzene. Deposition parameters: Vacuum degree 1×10 -3 The deposition parameters are: Pa, deposition temperature 70-80℃, target power 3.0kW, deposition rate 1.5-2.0nm / min, and film thickness 130-160nm. This thickness range ensures a basic blocking rate of ≥30% for blue light at 415-455nm. In-situ UV curing: After deposition, immediately turn on the 365nm UV lamp (30W power) and irradiate for 2 minutes to allow the azobenzene molecules to undergo a cross-linking reaction with the oxide lattice, fix the molecular orientation, and prevent loss during use (azobenzene residual rate ≥95% after abrasion resistance test).

[0013] Step S5: Deposition of MXene / MOF composite anti-yellowing layer. This layer achieves long-term anti-yellowing through a dual mechanism. The process parameters are as follows: Target design: Ti3C2T XA composite target of MXene (10%) and Zr-based MOF (UiO-66, 90%), wherein Ce is loaded in the porous structure of UiO-66. 3+ (Loading content 5wt%). MXene was prepared by HF etching of Ti3AlC2, with a sheet thickness of 5-10 nm; UiO-66 was synthesized by a solvothermal method, with a pore size of approximately 0.8 nm; Deposition conditions: Vacuum degree 2×10 -3 The deposition parameters were: Pa, deposition temperature 65-75℃, target power 2.0kW, deposition rate 2.5-3.0nm / min, and film thickness 90-110nm. Low-energy ion beam assistance (80eV, 15mA) was used during deposition to avoid damaging the MXene layered structure. Performance control: The permeability of this layer is ≤0.02g / (m²). 2 •d) (tested using the cup method), forming a physical barrier; simultaneously, UiO-66 slowly releases Ce under ultraviolet stimulation. 3+ It replenishes antioxidants that have been oxidized.

[0014] Step S6: Interlayer processing and post-processing Interlayer stress relief: In steps S3 to S5, after each layer is deposited, Ar gas (10 sccm) is introduced to maintain a vacuum of 2 × 10⁻⁶. -3 Pa, let stand for 5 minutes, and relieve the thermal stress accumulated between layers through gas molecule diffusion; Low-temperature plasma annealing: After all film layers have been deposited, annealing is performed under a vacuum of 1×10⁻⁶. -3 Air is introduced at Pa (flow rate 5 sccm), RF power supply is started (power 50W), and annealing is performed for 10 minutes. This process can promote interlayer atomic diffusion and enhance interfacial bonding. Cooling and removal: Turn off the power and allow to cool naturally for 30 minutes to room temperature, until the vacuum level drops to ≤5×10⁻⁶. -3 When the vacuum is broken at Pa, use clean tweezers to pick up the film to avoid film contamination (contamination rate controlled ≤0.5%).

[0015] Compared with the prior art, the present invention can achieve the following technical effects: 1. By utilizing the photoisomerization properties of azobenzene derivatives, intelligent adjustment of blue light blocking rate is achieved, resolving the contradiction between "indoor color shift" and "insufficient outdoor protection" in traditional lenses.

[0016] 2. Synergistic mechanism of long-lasting anti-yellowing: MXene's two-dimensional nanobarrier and MOF's Ce 3+ The sustained-release system provides dual protection and extends service life.

[0017] 3. The highly stable film structure is achieved through a three-stage stress control process of "ion beam assistance + interlayer static setting + low-temperature annealing", resulting in stable film adhesion.

[0018] Of course, any product implementing this invention does not necessarily need to achieve all of the technical effects described above at the same time. Attached Figure Description

[0019] The accompanying drawings, which are included to provide a further understanding of the invention and form part of this invention, illustrate exemplary embodiments of the invention and are used to explain the invention, but do not constitute an undue limitation of the invention. In the drawings: Figure 1 This is a flow chart of the sintering process of PTFE hollow fiber tube based on the membrane wrapping effect according to an embodiment of the present invention. Detailed Implementation

[0020] The following will describe in detail the implementation of the present invention with reference to the accompanying drawings and embodiments, so that the process of how the present invention uses technical means to solve technical problems and achieve technical effects can be fully understood and implemented accordingly.

[0021] Example 1: Preparation of PC substrate blue light blocking and anti-yellowing lenses This embodiment provides a vacuum coating process for anti-blue light and anti-yellowing lenses. PC resin lenses are selected as the substrate. The substrate has a diameter of 70mm, a thickness of 1.5mm, a light transmittance of 91%, and a haze of 0.3%. Figure 1 As shown, it includes the following steps: S1: Pretreatment. First, the substrate is placed in an ultrasonic cleaning tank using a neutral cleaning agent with a pH of 7.0, and ultrasonically cleaned for 10 minutes at 50°C. Then, it is transferred to a deionized water tank with a resistivity of 18.2 MΩ·cm and rinsed three times, each time for 2 minutes. Finally, the substrate surface is dried with hot air at 60°C for 5 minutes. After drying, the surface water residue is measured to be 8 mg / m³. 2 .

[0022] S2: Air plasma activation, first evacuate the vacuum chamber to 5×10 -4 The vacuum level was set to Pa and maintained for 30 minutes. Then, dehydrated air was introduced at a flow rate of 28 sccm. The radio frequency power supply was started and the power was set to 120W. The treatment lasted for 4 minutes. After activation, the substrate surface was tested and found to have a strength of 58 mN / m and a water contact angle of 28°.

[0023] S3: Adhesion-enhancing layer deposition, using a SiO2-ZrO2 composite target (molar ratio 7:3), under a vacuum of 2×10⁻⁶.- 3 Under the conditions of Pa and temperature of 65℃, the target power was set to 2.5kW, the deposition rate to 2.5nm / min, and the deposition thickness to 65nm. Ion beam assisted deposition was used during the deposition process, with an ion beam energy of 100eV and a current of 20mA.

[0024] S4: Dynamic blue light protection layer deposition, using a ZrO2-Al2O3-Y2O3-azobenzene derivative composite target, at a vacuum degree of 1×10 -3 In an environment with a pressure of 75°C and a target power of 3.0 kW, a deposition rate of 1.8 nm / min, and a deposition thickness of 145 nm, the material was immediately irradiated with a 365 nm wavelength, 30 W UV lamp for 2 minutes for in-situ curing after deposition.

[0025] S5: MXene / MOF composite anti-yellowing layer deposition, using Ti3C2T X A composite target with UiO-66 (ratio 10:90) at a vacuum of 2×10⁻⁶ -3 Under the conditions of Pa and temperature of 70℃, the target power is 2.0kW, the deposition rate is 2.8nm / min, the deposition thickness is 100nm, and the energy of ion beam assisted deposition during the deposition process is 80eV and the current is 15mA.

[0026] S6: Post-processing, at a vacuum level of 1×10⁻⁶ -3 Air was introduced at 5 sccm under pressure, the RF power supply was started and set to 50W, and low-temperature plasma annealing was performed for 10 minutes, followed by natural cooling for 30 minutes. When the vacuum level dropped to 3 × 10⁻⁶ Pa, the annealing was continued. -3 The vacuum was broken and the lens removed at Pa. Performance test results showed that the lens had a 32% blocking rate for 415-455nm blue light indoors and 43% outdoors, with a response time of 8 seconds; after 1500 hours of xenon lamp aging test, the yellowing index Δb was 0.7, and Ce... 3+ The residue rate is 72%; the visible light transmittance at 550nm is 93.1% and the color difference value ΔE is 1.3; the adhesion in the cross-cut test reaches level 0, and there is no peeling after boiling in water at 80℃ for 2 hours; after being placed at 40℃ and 90% relative humidity for 6 months, the blue light blocking rate decreases by only 4%.

[0027] Example 2: Preparation of anti-blue light and anti-yellowing lenses on glass substrates High borosilicate glass was selected as the substrate, with a diameter of 65 mm, a thickness of 1.0 mm, and a surface roughness Ra of 0.01 μm. During the fabrication process, except for the following parameter adjustments, the remaining steps were consistent with Example 1: the deposition temperature of the adhesion-promoting layer was set to 100℃, the deposition thickness of the dynamic blue light blocking layer was 150 nm, and the deposition thickness of the MXene / MOF composite anti-yellowing layer was 105 nm. Performance test results showed that the lens achieved a 31% blocking rate for 415-455 nm blue light indoors and 44% outdoors, with a response time of 7 seconds; after 1500 hours of xenon lamp aging testing, the yellowing index Δb was 0.6, and the Ce... 3+ The residual rate is 75%; the visible light transmittance at 550nm is 94.2%, and the color difference value ΔE is 1.2; after the Taber abrasion test (using a CS-10 grinding wheel, 500g load), the haze change is 0.2%; after 30 cycles of hot and cold cycling from -40℃ to 60℃, no cracks are generated in the lens.

[0028] Comparative Example 1: Traditional Fixed Barrier Rate Process The lens was manufactured using a traditional process, specifically employing a SiO2-TiO2 blue light blocking layer (fixed blocking rate of 35%) and a SiO2-CeO2 anti-yellowing layer, with other process parameters similar to those in Example 1. Test results showed that the lens maintained a fixed blue light blocking rate of 35%, with a color difference value ΔE of 1.8 in an indoor environment (indicating a noticeable yellow tint), and insufficient protection in an outdoor environment. After 1500 hours of xenon lamp aging testing, the yellowing index Δb reached 2.1 (exceeding industry standards). The gas cost per batch was 280 yuan, 2.5 times that of the process described in this invention. The cross-cut adhesion test only achieved level 1, indicating localized detachment.

[0029] Comparative Example 2: Anti-yellowing layer without MXene The process is similar to that in Example 1, but the anti-yellowing layer uses pure UiO-66 loaded with Ce. 3+ No MXene was added. Test results showed that after 1500 hours of xenon lamp aging test, the yellowing index Δb* of this lens was 1.4 (higher than 0.7 in Example 1 of this invention); the water permeability of the anti-yellowing layer was 0.05 g / (m 2 •d), is 2.5 times that of Embodiment 1 of the present invention; Ce 3+ The residual rate was 45%, which is lower than 72% in Example 1 of this invention.

[0030] The foregoing description illustrates and describes several preferred embodiments of the present invention. However, as previously stated, it should be understood that the present invention is not limited to the forms disclosed herein and should not be construed as excluding other embodiments. It can be used in various other combinations, modifications, and environments, and can be altered within the scope of the inventive concept described herein through the foregoing teachings or techniques or knowledge in related fields. Any modifications and variations made by those skilled in the art that do not depart from the spirit and scope of the present invention should be within the protection scope of the appended claims.

Claims

1. A vacuum coating process for anti-blue light and anti-yellowing lenses, characterized in that, Includes the following steps: S1: Substrate pretreatment: The lens substrate is sequentially ultrasonically cleaned, rinsed with pure water, and dried with hot air, and then placed on a planetary rotating fixture in a vacuum chamber. S2: Air plasma activation, vacuum chamber evacuated to 5×10⁻⁶. -4 Pa and hold pressure for 30 min, then introduce dehydrated compressed air, and perform plasma activation through radio frequency power supply with an air flow rate of 25-30 sccm, radio frequency power of 120W, and a processing time of 4 min, so that the surface energy of the substrate is ≥55mN / m; S3: Adhesion promoting layer deposition. Mid-frequency magnetron sputtering technology was used with a SiO2-ZrO2 composite target as the target material. A 50-80 nm thick adhesion promoting layer was deposited under the conditions of vacuum degree 2×10-3 Pa, deposition temperature 60-100℃, and target power 2.5kW. Ion beam assisted deposition was used during the deposition process with ion beam energy of 100eV and current of 20mA. S4: Dynamic blue light protection layer deposition, employing mid-frequency magnetron sputtering technology, using a ZrO2-Al2O3-Y2O3-azobenzene derivative composite target as the target material, at a vacuum degree of 1×10⁻⁶. -3 A 130-160nm thick blue light blocking layer was deposited under the conditions of Pa, deposition temperature of 70-80℃, and target power of 3.0kW. After deposition, in-situ UV curing was performed at a curing wavelength of 365nm, a power of 30W, and a time of 2min. S5: MXene / MOF composite anti-yellowing layer deposition, using mid-frequency magnetron sputtering technology, with Ti3C2T X A 90-110 nm thick anti-yellowing layer was deposited using an MXene and Zr-based MOF composite target as the target material under the conditions of a vacuum degree of 2×10⁻³ Pa, a deposition temperature of 65-75℃, and a target power of 2.0 kW. The composite target contained 10% MXene, 90% MOF, and was loaded with Ce. 3+ ; S6: Post-processing, at a vacuum level of 1×10⁻⁶ -3 Air was introduced at a flow rate of 5 sccm under Pa conditions for low-temperature plasma annealing at a power of 50 W for 10 minutes. The plasma was then allowed to cool naturally to room temperature before being removed.

2. The vacuum coating process for anti-blue light and anti-yellowing lenses according to claim 1, characterized in that, The ultrasonic cleaning in step S1 uses a neutral cleaning agent with a pH value of 6.5-7.5, a cleaning temperature of 50°C, and a time of 10 minutes. The hot air drying temperature is 60°C, the air velocity is 2 m / s, and the time is 5 minutes.

3. The vacuum coating process for anti-blue light and anti-yellowing lenses according to claim 1, characterized in that, The compressed air in step S2 is treated by a molecular sieve dehydration device, and the water content is ≤0.1ppm. The rotation speed of the planetary self-rotating clamp is 5rpm.

4. The vacuum coating process for anti-blue light and anti-yellowing lenses according to claim 1, characterized in that, In step S3, the molar ratio of SiO2 to ZrO2 in the SiO2-ZrO2 composite target is 7:3, the deposition rate is 2-3 nm / min, and the deposition temperature is 60-70℃ for resin substrates and 100℃ for glass substrates.

5. The vacuum coating process for anti-blue light and anti-yellowing lenses according to claim 1, characterized in that, The azobenzene derivative mentioned in step S4 is 4-hydroxyazobenzene, the molar ratio of ZrO2-Al2O3-Y2O3 is 5:4:1, the deposition rate is 1.5-2.0 nm / min, the energy of ion beam assisted deposition is 120 eV, and the current is 25 mA.

6. The vacuum coating process for anti-blue light and anti-yellowing lenses according to claim 1, characterized in that, The Zr-based MOF mentioned in step S5 is UiO-66, with a deposition rate of 2.5-3.0 nm / min, an ion beam assisted deposition energy of 80 eV, a current of 15 mA, and a water permeability of the formed anti-yellowing layer ≤ 0.02 g / (m²). 2 •d).

7. The vacuum coating process for anti-blue light and anti-yellowing lenses according to claim 1, characterized in that, In steps S3 to S5, after each film layer is deposited, Ar gas is introduced at 10 sccm to maintain a vacuum of 2 × 10⁻⁶. -3 Pa, let stand for 5 minutes before depositing the next layer.

8. The vacuum coating process for anti-blue light and anti-yellowing lenses according to claim 1, characterized in that, The targets used in each step are all vacuum hot-pressed sintered composite targets with a target size of Φ100×5mm and a target-substrate distance of 150mm. Before deposition, the targets are preheated to 100℃ and held for 30min.

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