Photochromic lens and preparation method thereof

Abstract

The present invention provides a photochromic lens and a preparation method thereof. The photochromic lens comprises a lens substrate, a photochromic substrate, a photochromic coating and a protective layer which are arranged in sequence. The color changing effect of the photochromic lens is achieved by two structures, the photochromic substrate and the photochromic coating. The combination of the two structures makes the obtained photochromic lens have the advantages of deep color changing depth and fast fading rate. The lens substrate has more refractive index varieties to choose from, which can meet the wearer's more diverse wearing needs.

Description

Technical Field

[0001] The invention belongs to the technical field of lenses, and in particular relates to a photochromic lens and a preparation method thereof. Background Art

[0002] Photochromism refers to the phenomenon that the optical properties of materials undergo reversible changes under the irradiation of ultraviolet light. Photochromism can change the color and transmittance and this change is reversible. Photochromic lenses can filter out ultraviolet light in sunlight, reduce the intensity of light that hits the eyes outdoors, make the wearer's vision more comfortable outdoors, and reduce ultraviolet rays to ensure the wearer's eye health.

[0003] At present, the existing photochromic lenses mainly achieve the photochromic effect by dissolving the color-changing factor into the lens substrate or preparing the color-changing factor into a coating, applying it on the lens surface and forming it by light curing or heat curing. However, the color depth of the above-mentioned types of photochromic lenses is difficult to deepen, and the fading rate after color change is slow. After the wearer enters the room from the outside, the lens is likely to retain the base color for a long time, affecting the wearing effect. On the other hand, the thickness of the color-changing coating of the photochromic lens is relatively thick and the texture is relatively soft, which is easy to be scratched and left scratches during the wearing process.

[0004] CN108084327A discloses a method for preparing an impact-resistant, fast-fading substrate, wherein a lens having a color-changing ability is obtained by adding a spiropyran or spirooxazine color-changing substance into an acrylic monomer, a styrene solvent, a free radical initiator, and a release agent, and then casting and curing the resulting lens into a film. The photochromic lens described in the invention has advantages such as good mechanical properties and a fast fading rate, but since the color-changing substance is dispersed in the lens substrate, the content of the color-changing substance is required to be high and the concentration is difficult to increase, so the color change depth is shallow and the production cost is high.

[0005] CN103952135A discloses a photochromic material showing an improved fading rate and provides a method for preparing a corresponding photochromic product. The invention synthesizes a spiropyran material without unsaturated groups and adds electron-withdrawing non-conjugated groups and medium to strong electron-donating groups thereto. The photochromic material can achieve rapid mutual conversion from a colorless ground state to a colored active state, thereby enabling the lens to have a faster coloring and fading rate. The invention achieves rapid fading of the lens by modifying the color-changing substance. However, the process for synthesizing the color-changing substance is complicated, difficult, and difficult to produce, and the production cost is high. The compatibility of the color-changing substance with various organic resin substrates is uncertain, and the actual color-changing effect needs further verification.

[0006] Therefore, it is desirable to develop a photochromic lens that has deep color change, fast fading, and excellent mechanical properties. Summary of the invention

[0007] In view of the deficiencies in the prior art, the purpose of the present invention is to provide a photochromic lens and a preparation method thereof. The photochromic lens combines a photochromic substrate and a photochromic coating, so that the obtained photochromic lens has the advantages of deep color change and fast fading, and will not affect the base color of the lens substrate. At the same time, the photochromic substrate is used to separate the photochromic layer from the lens substrate, so that the lens substrate can choose more refractive index varieties to meet the wearer's more diverse wearing needs.

[0008] In order to achieve the purpose of the invention, the present invention adopts the following technical solutions:

[0009] In a first aspect, the present invention provides a photochromic lens, wherein the photochromic lens comprises a lens substrate, a photochromic substrate, a photochromic coating and a protective layer which are arranged in sequence.

[0010] The photochromic lens provided by the present invention comprises a lens substrate, a photochromic substrate, a photochromic coating and a protective layer which are arranged in sequence. When actually worn, the lens substrate is close to the human eye. The color changing effect of the photochromic lens provided by the present invention is achieved by the two structures of the photochromic substrate and the photochromic coating. The combination of the two achieves the effect of improving the color changing depth and fading rate. The photochromic substrate is combined with the lens substrate by pouring and curing, has strong adaptability, and effectively separates the photochromic coating from the lens substrate, avoiding the problem that the photochromic coating cannot be applied to lens substrates of various refractive index materials. This leads to a decrease in the color-changing performance of the photochromic coating (shallow color-changing depth, slow color fading rate, obvious base color, etc.), and also avoids the problem of poor adhesion of the photochromic coating on the lens substrate and inability to adhere firmly. On the one hand, the lens substrate has more refractive index varieties to choose from, meeting the wearer's more diverse wearing needs. On the other hand, the mechanical properties of the surface of the resulting photochromic lens are significantly improved, and the friction resistance, impact resistance, coating firmness and other properties are better. Finally, a protective layer is added to effectively protect the photochromic substrate and photochromic coating, making the photochromic lens more weather-resistant and longer in service life.

[0011] Preferably, the material of the lens substrate includes any one of polyurethane (for example, Mitsui Chemicals MR-7, MR-8, MR-10 or MR174), carbonyl acrylate (CR-39), polymethacrylate (PMMA) or polycarbonate (PC) or a combination of at least two thereof.

[0012] Preferably, the diameter of the lens substrate is 65-80 mm, for example, 67 mm, 69 mm, 71 mm, 73 mm, 75 mm, 77 mm or 79 mm.

[0013] Preferably, the center thickness of the lens substrate is 2-5 mm, for example, 2.5 mm, 3 mm, 3.5 mm, 4 mm or 4.5 mm.

[0014] Preferably, the edge thickness of the lens substrate is 2-15 mm, for example, 4 mm, 6 mm, 8 mm, 10 mm, 12 mm or 14 mm.

[0015] Preferably, the photochromic substrate has a thickness of 1-2 μm, such as 1.2 μm, 1.4 μm, 1.6 μm or 1.8 μm.

[0016] As a preferred technical solution of the present invention, the purpose of limiting the thickness of the photochromic substrate to 1~2 μm is to ensure that the photochromic substrate has a certain transmittance while having an effective photochromic effect, and will not affect the transmittance and wearing comfort of the lens substrate. If the thickness of the photochromic substrate is too thick, the transmittance of the lens will be lower. If the thickness of the photochromic substrate is too thin, the color change depth of the lens will be shallower.

[0017] Preferably, the raw material for preparing the photochromic substrate is a photochromic substrate solution, and the photochromic substrate solution comprises the following components in parts by weight:

[0018] Resin monomer A 40~45 parts by weight

[0019] Resin monomer B 20~30 parts by weight

[0020] Resin monomer C 20~30 parts by weight

[0021] Color changing liquid 5~20 parts by weight

[0022] Initiator 0.04~0.1 parts by weight;

[0023] The resin monomer A is a Japanese Mitsui Chemicals MR-8A monomer, the resin monomer B is a Japanese Mitsui Chemicals MR-8B1 monomer, and the resin monomer C is a Japanese Mitsui Chemicals MR-8B2 monomer.

[0024] As a preferred technical solution of the present invention, the purpose of selecting the above three resin monomers to be combined as the main resin of the photochromic substrate solution is that the above three resin monomers have good crystallinity, and the combination of the three resin monomers can more effectively stretch the distance between polyurethane molecules, which is beneficial to the uniform distribution of the color-changing substance and the rapid reaction of the color-changing substance therein, making the color change rate faster.

[0025] The resin monomer A may be 40.5 parts by weight, 41 parts by weight, 41.5 parts by weight, 42 parts by weight, 42.5 parts by weight, 43 parts by weight, 43.5 parts by weight, 44 parts by weight or 44.5 parts by weight.

[0026] The resin monomer B may be 22 parts by weight, 24 parts by weight, 26 parts by weight, or 28 parts by weight.

[0027] The resin monomer C may be 22 parts by weight, 24 parts by weight, 26 parts by weight, or 28 parts by weight.

[0028] The color-changing liquid can be 7 parts by weight, 9 parts by weight, 11 parts by weight, 13 parts by weight, 15 parts by weight, 17 parts by weight or 19 parts by weight.

[0029] The initiator may be 0.05 parts by weight, 0.06 parts by weight, 0.07 parts by weight, 0.08 parts by weight, or 0.09 parts by weight.

[0030] Preferably, the color-changing liquid comprises any one or a combination of at least two of spiropyran compounds, spirooxazine compounds, succinic anhydride compounds or naphthopyran compounds; the color-changing liquid may specifically be SunSensors TM -MR-8 TM Color changing fluid.

[0031] Preferably, the initiator includes any one of monomethyltin dichloride, dimethyltin dichloride, trimethyltin monochloride, diethyltin dichloride, dimethyltin dibromide, dibutyltin dichloride or trimethyltin monobromide, or a combination of at least two thereof.

[0032] Preferably, the photochromic substrate solution further comprises any one of an additive, a release agent or a color-correcting agent, or a combination of at least two thereof.

[0033] Preferably, the content of the auxiliary agent added to the photochromic substrate solution is 0.1-0.5 parts by weight, such as 0.6 parts by weight, 0.7 parts by weight, 0.8 parts by weight or 0.9 parts by weight.

[0034] Preferably, the additive comprises any one of a defoamer, an antioxidant or a leveling agent, or a combination of at least two thereof, and specifically may be SSS-MR8 Additive.

[0035] Preferably, the content of the release agent in the photochromic substrate solution is 0.05-0.1 parts by weight, such as 0.06 parts by weight, 0.07 parts by weight, 0.08 parts by weight or 0.09 parts by weight.

[0036] Preferably, the release agent includes any one of isopropyl phosphate, diisopropyl phosphate or butyric acid phosphate or a combination of at least two thereof, and specifically JP-506H can be selected.

[0037] Preferably, the content of the color-correcting agent in the photochromic substrate solution is 0.5-1 part by weight, for example, 0.6 part by weight, 0.7 part by weight, 0.8 part by weight or 0.9 part by weight.

[0038] Preferably, the color-correcting agent includes an organic pigment, which is soluble in an alcohol solvent and is used to adjust the color of the lens. Specifically, MR-8 blue agent can be selected.

[0039] Preferably, the photochromic substrate solution is prepared by the following method, which comprises the following steps:

[0040] (A1) mixing part of the resin monomer A and the initiator to obtain a mixture A; mixing part of the resin monomer A, a color-changing liquid, an optional auxiliary agent and an optional release agent to obtain a mixture B;

[0041] (A2) Mixing the mixture A obtained in step (A1), the mixture B, the resin monomer B, the resin monomer C and an optional color correcting agent to obtain the photochromic substrate solution.

[0042] Preferably, the mixing in step (A2) is performed under vacuum conditions in a water bath.

[0043] Preferably, the mixing temperature in step (A2) is 5-15°C, for example, 6°C, 7°C, 8°C, 9°C, 10°C, 11°C, 12°C, 13°C or 14°C.

[0044] Preferably, the mixing time in step (A2) is 30 to 60 min, for example, 35 min, 40 min, 45 min, 50 min or 55 min.

[0045] Preferably, the thickness of the photochromic coating is 5-8 μm, for example, 5.5 μm, 6 μm, 6.5 μm, 7 μm, 7.5 μm or 8 μm.

[0046] As a preferred technical solution of the present invention, the thickness of the photochromic coating in the photochromic lens provided by the present invention is 5-8 μm, which can ensure a deep color change depth, thereby avoiding the problem that the lens surface is soft and easy to be scratched and leave scratches due to the excessive thickness of the photochromic coating.

[0047] Preferably, the raw material for preparing the photochromic coating is a photochromic coating liquid, and the photochromic coating liquid comprises the following components in parts by weight:

[0048] Polyol 5-15 parts by weight

[0049] Isocyanate 65~75 parts by weight

[0050] Color change factor 5~10 parts by weight

[0051] Light stabilizer 0.5~1 part by weight.

[0052] The polyol may be 6 parts by weight, 7 parts by weight, 8 parts by weight, 9 parts by weight, 10 parts by weight, 11 parts by weight, 12 parts by weight, 13 parts by weight, or 14 parts by weight.

[0053] The isocyanate may be 66 parts by weight, 67 parts by weight, 68 parts by weight, 69 parts by weight, 70 parts by weight, 71 parts by weight, 72 parts by weight, 73 parts by weight, or 74 parts by weight, etc.

[0054] The color change factor can be 6 parts by weight, 7 parts by weight, 8 parts by weight, 9 parts by weight, etc.

[0055] The light stabilizer may be in an amount of 0.6 parts by weight, 0.7 parts by weight, 0.8 parts by weight, 0.9 parts by weight, etc.

[0056] Preferably, the photochromic coating further comprises any one of a solvent, a leveling agent, a first surfactant or an antioxidant, or a combination of at least two thereof.

[0057] Preferably, the content of the solvent in the photochromic coating is 14 to 20 parts by weight, for example, 15 parts by weight, 16 parts by weight, 17 parts by weight, 18 parts by weight or 19 parts by weight.

[0058] Preferably, the content of the leveling agent in the photochromic coating is 0.5-1 part by weight, for example, 0.6 part by weight, 0.7 part by weight, 0.8 part by weight or 0.9 part by weight.

[0059] Preferably, the content of the surfactant in the photochromic coating is 0.2-0.5 parts by weight, such as 0.25 parts by weight, 0.3 parts by weight, 0.35 parts by weight, 0.4 parts by weight or 0.45 parts by weight.

[0060] Preferably, the content of the antioxidant in the photochromic coating is 0.2-0.5 parts by weight, such as 0.25 parts by weight, 0.3 parts by weight, 0.35 parts by weight, 0.4 parts by weight or 0.45 parts by weight.

[0061] Preferably, the photochromic coating is prepared by the following method, which comprises the following steps:

[0062] (B1) dissolving a color-changing factor in a solvent to obtain a color-changing concentrate; mixing an isocyanate, a polyol, a light stabilizer, an optional leveling agent, an optional antioxidant, and an optional first surfactant to obtain a white material;

[0063] (B2) Mixing the color-changing concentrated solution obtained in step (B1) with white material to obtain the photochromic coating solution.

[0064] Preferably, the temperature for dissolving the color-changing factor in the solvent in step (B1) is 50-70°C, for example, 52°C, 54°C, 56°C, 58°C, 60°C, 62°C, 64°C, 66°C or 68°C.

[0065] Preferably, the mixing time in step (B1) is 1 to 2 h, for example, 1.2 h, 1.4 h, 1.6 h or 1.8 h.

[0066] Preferably, the mixing time in step (B2) is 1 to 2 h, for example, 1.2 h, 1.4 h, 1.6 h or 1.8 h.

[0067] Preferably, the protective layer has a thickness of 10-20 μm, for example, 12 μm, 14 μm, 16 μm, 18 μm or 20 μm.

[0068] Preferably, the raw material for preparing the protective layer is a protective coating liquid, and the protective coating liquid comprises the following components in parts by weight:

[0069] Reactive diluent monomer 50~70 parts by weight

[0070] Oligomer 15~25 parts by weight

[0071] The second surfactant 0.5-1 parts by weight

[0072] Photoinitiator 0.2~0.5 parts by weight.

[0073] Wherein, the reactive diluent monomer may be 52 parts by weight, 54 parts by weight, 56 parts by weight, 58 parts by weight, 60 parts by weight, 62 parts by weight, 64 parts by weight, 66 parts by weight or 68 parts by weight, etc.

[0074] The oligomer may be 16 parts by weight, 17 parts by weight, 18 parts by weight, 19 parts by weight, 20 parts by weight, 21 parts by weight, 22 parts by weight, 23 parts by weight, 24 parts by weight, etc.

[0075] The second surfactant may be 0.6 parts by weight, 0.7 parts by weight, 0.8 parts by weight, 0.9 parts by weight, etc.

[0076] The photoinitiator may be 0.25 parts by weight, 0.3 parts by weight, 0.35 parts by weight, 0.4 parts by weight, or 0.45 parts by weight.

[0077] Preferably, the reactive diluent monomer includes any one of trimethylolpropane triacrylate (TMPTA), dimethylolpropane triacrylate (DTMPTTA), neopentyl glycol diacrylate (SR-247), tetrahydrofuran acrylate (THFMA), pentaerythritol triacrylate (PETA) or pentaerythritol tetraacrylate (PETTA) or a combination of at least two thereof.

[0078] Preferably, the oligomer includes any one of bisphenol A epoxy resin, silicone epoxy resin or epoxy acrylate oligomer (specifically, BRO11300 may be selected) or a combination of at least two thereof.

[0079] Preferably, the second surfactant comprises N-methylaminopropyltrimethoxysilane and / or γ-glycidyloxypropyltrimethoxysilane.

[0080] The second surfactant can be any one of SIM6500, BYK-348, BYK-333, RK5345 or A-187.

[0081] Preferably, the photoinitiator comprises diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide and / or bisacryloylphosphine oxide.

[0082] The photoinitiator may be any one of diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide LUCIRIN TPO, DAROCUR4265, DAROCUR1173 or bisacryloylphosphine oxide IGACURE819.

[0083] Preferably, the protective coating liquid further comprises a solvent.

[0084] Preferably, the content of the solvent in the protective coating liquid is 10-15 parts by weight, for example, 11 parts by weight, 12 parts by weight, 13 parts by weight or 14 parts by weight.

[0085] Preferably, the solvent includes any one of xylene, N,N-dimethylformamide or methylpyrrolidone, or a combination of at least two thereof.

[0086] Preferably, the protective liquid is prepared by the following method, which comprises: mixing a reactive diluent monomer, an oligomer, a photoinitiator, a second surfactant and optionally a solvent to obtain the protective liquid;

[0087] Preferably, the mixing time is 1 to 2 h, for example, 1.2 h, 1.4 h, 1.6 h or 1.8 h.

[0088] Preferably, the photochromic lens comprises a first strengthening layer, a lens substrate, a photochromic substrate, a photochromic coating, a protective layer and a second strengthening layer which are arranged in sequence.

[0089] As a preferred technical solution of the present invention, a strengthening layer is provided on the inner side of the lens substrate (the side close to the human eye) and the outer side of the protective layer (the side away from the human eye), which can improve the mechanical properties of the photochromic lens.

[0090] Preferably, the thickness of the first strengthening layer and the second strengthening layer are independently 2-4 μm, for example, 2.2 μm, 2.4 μm, 2.6 μm, 2.8 μm, 3 μm, 3.2 μm, 3.4 μm, 3.6 μm or 3.8 μm.

[0091] Preferably, the raw materials for preparing the first strengthening layer and the second strengthening layer are organic silicone resin coating liquid.

[0092] Preferably, the photochromic lens comprises a first anti-reflection film, a first strengthening layer, a lens substrate, a photochromic substrate, a photochromic coating, a protective layer, a second strengthening layer and a second anti-reflection film which are arranged in sequence.

[0093] As a preferred technical solution of the present invention, an anti-reflection film may be further evaporated on the strengthening layer to further improve the transmittance and friction resistance of the photochromic lens.

[0094] In a second aspect, the present invention provides a method for preparing the photochromic lens according to the first aspect, the method comprising the following steps:

[0095] (1) Using the lens substrate as the lower mold of the mold and combining it with the glass upper mold to form a mold, pouring the prepared raw materials of the photochromic substrate into the mold, curing and forming, removing the glass upper mold, and obtaining a lens with the photochromic substrate attached;

[0096] (2) coating the raw materials for preparing the photochromic coating on the photochromic substrate of the lens attached with the photochromic substrate obtained in step (1), and curing and forming the lens to obtain a lens coated with the photochromic layer;

[0097] (3) coating the raw materials for preparing the protective layer on the photochromic layer of the lens coated with the photochromic layer obtained in step (2), and UV curing to obtain the photochromic lens.

[0098] Preferably, the pouring temperature in step (1) is 15-20°C, for example, 15.5°C, 16°C, 16.5°C, 17°C, 17.5°C, 18°C, 18.5°C, 19°C or 19.5°C.

[0099] Preferably, the curing time in step (1) is 10 to 20 hours, such as 12 hours, 14 hours, 16 hours or 18 hours.

[0100] Preferably, the curing temperature in step (1) is 110-130°C, for example, 112°C, 114°C, 116°C, 118°C, 120°C, 122°C, 124°C, 126°C or 128°C.

[0101] Preferably, before the coating in step (2), the step of pre-treating the surface of the lens attached with the photochromic substrate obtained in step (1) is also included.

[0102] Preferably, the surface pretreatment comprises: soaking the lens with the photochromic substrate obtained in step (1) in a sodium hydroxide solution, and then washing it in an alkaline detergent and water in sequence to complete the surface pretreatment.

[0103] Preferably, the mass percentage of sodium hydroxide in the sodium hydroxide solution is 20-30%, for example, 22%, 24%, 26% or 28%.

[0104] Preferably, the soaking is performed under ultrasonic conditions.

[0105] Preferably, the power of the ultrasound is 20-90 mV, for example, 30 mV, 40 mV, 50 mV, 60 mV, 70 mV or 80 mV, etc.

[0106] Preferably, the soaking time is 5 to 20 min, for example, 7 min, 9 min, 11 min, 13 min, 15 min, 17 min or 19 min, etc.

[0107] Preferably, the curing temperature in step (2) is 110-130°C, for example, 112°C, 114°C, 116°C, 118°C, 120°C, 122°C, 124°C, 126°C or 128°C.

[0108] Preferably, the curing time in step (2) is 1 to 2 h, for example, 1.2 h, 1.4 h, 1.6 h, 1.8 h or 2 h.

[0109] Preferably, the UV curing time in step (3) is 2 to 5 s, for example, 2.5 s, 3 s, 3.5 s, 4 s or 4.5 s.

[0110] Preferably, the power of the UV curing in step (3) is 400-600 mW / cm 2 , for example 420 mW / cm 2 , 440 mW / cm 2 , 460 mW / cm 2 , 480 mW / cm 2 , 500 mW / cm 2 , 520 mW / cm 2 , 540 mW / cm 2 , 560 mW / cm 2 or 580 mW / cm 2 wait.

[0111] Preferably, after the UV curing in step (3), the step further includes coating a silicone resin coating on the surface of the formed protective layer and the surface of the lens substrate, respectively, and curing and forming the coating.

[0112] Preferably, the curing time is 2 to 3 h, for example, 2.2 h, 2.4 h, 2.6 h or 2.8 h.

[0113] Preferably, the curing temperature is 100-130°C, for example, 102°C, 104°C, 106°C, 108°C, 110°C, 112°C, 114°C, 116°C, 118°C, 120°C or 125°C.

[0114] Compared with the prior art, the present invention has the following beneficial effects:

[0115] (1) The photochromic lens provided by the present invention comprises a lens substrate, a photochromic substrate, a photochromic coating and a protective layer arranged in sequence. The photochromic substrate and the photochromic coating are matched and the above two structures are used to jointly achieve the color change of the photochromic lens, so that the photochromic lens can show the base color of the lens substrate indoors and turn black after being exposed to outdoor light. It has the advantages of deep color change and fast fading rate, and will not affect the base color of the lens substrate.

[0116] (2) The lens substrate of the photochromic lens provided by the present invention is in contact with the photochromic substrate, and the lens substrate is separated from the photochromic coating, thereby avoiding the problem that the photochromic coating cannot be applied to lens substrates of various refractive index materials, which leads to a decrease in the color change performance of the photochromic coating (shallow color change depth, slow color fading rate, obvious base color, etc.), and also avoids the problem that the photochromic coating has poor adhesion to the lens substrate and cannot be firmly attached, so that the lens substrate has a wider range of refractive index varieties to choose from, meeting the wearer's more diverse wearing needs;

[0117] (3) The thickness of the photochromic coating in the photochromic lens provided in the present application is thinner, so that the photochromic lens has higher transmittance and better surface mechanical properties. DETAILED DESCRIPTION

[0118] The technical solution of the present invention is further described below by specific implementation methods. It should be understood by those skilled in the art that the embodiments are only to help understand the present invention and should not be regarded as specific limitations of the present invention.

[0119] Some of the raw material information involved in the specific implementation method is shown in Table 1:

[0120] Table 1

[0121]

[0122] Example 1

[0123] A photochromic lens, which is composed of a first strengthening layer, a lens substrate, a photochromic substrate, a photochromic coating, a protective layer and a first strengthening layer arranged in sequence;

[0124] The lens substrate is made of carbonyl acrylate (CR-39), with a diameter of 70 mm, a center thickness of 4 mm, and an edge thickness of 8 mm.

[0125] The thickness of the photochromic substrate is 1.5 μm, and the raw material for preparation is a photochromic substrate solution, which includes the following components in parts by weight: 42 parts by weight of resin monomer A, 25 parts by weight of resin monomer B, 25 parts by weight of resin monomer C, 15 parts by weight of color-changing liquid, 0.05 parts by weight of initiator, 0.05 parts by weight of release agent, 0.7 parts by weight of color-correcting agent and 0.3 parts by weight of additive;

[0126] The preparation method of the photochromic substrate solution comprises the following steps:

[0127] (A1) Mixing part of the resin monomer A and the initiator for 30 minutes to obtain a mixture A; mixing the remaining part of the resin monomer A, the color-changing liquid, the auxiliary agent and the release agent at room temperature for 30 minutes to obtain a mixture B, wherein the mass ratio of the mixture A to the mixture B is 4:6;

[0128] (A2) Mixture A, mixture B, resin monomer B, resin monomer C and color correcting agent obtained in step (A1) are stirred for 50 min under low temperature of 10° C. and vacuumed in a water bath, and then allowed to stand for 50 min under vacuumed water bath to obtain the photochromic substrate solution.

[0129] The thickness of the photochromic coating is 7 μm, and the raw material for its preparation is a photochromic coating liquid, which includes the following components in parts by weight: 10 parts by weight of polyol, 70 parts by weight of isocyanate, 8 parts by weight of color change factor, 0.8 parts by weight of light stabilizer, 18 parts by weight of solvent, 0.8 parts by weight of leveling agent, 0.3 parts by weight of surfactant and 0.3 parts by weight of antioxidant;

[0130] The preparation method of the photochromic coating liquid comprises the following steps:

[0131] (B1) dissolving the color-changing factor in a solvent at 60°C and stirring for 30 min to obtain a color-changing concentrate; mixing isocyanate, polyol, light stabilizer, leveling agent, antioxidant and surfactant at room temperature for 1.5 h to obtain a white material;

[0132] (B2) The color-changing concentrated solution obtained in step (B1) and the white material are mixed at room temperature for 1.5 hours to obtain the photochromic coating solution.

[0133] The thickness of the protective layer is 15 μm, and the raw material for preparing the protective layer is a protective coating liquid, which includes the following components in parts by weight: 60 parts by weight of active diluent monomer, 20 parts by weight of oligomer, 0.7 parts by weight of surfactant, 0.3 parts by weight of photoinitiator and 12 parts by weight of xylene;

[0134] The preparation method of the protective liquid comprises: mixing a reactive diluent monomer, an oligomer, a photoinitiator, a second surfactant and xylene for 1.5 hours at room temperature in a light-proof condition to obtain the protective liquid.

[0135] The first strengthening layer and the second strengthening layer are both 3 μm thick and are silicone resin coatings.

[0136] The method for preparing the photochromic lens provided in this embodiment comprises the following steps:

[0137] (1) Using the lens substrate as the lower mold of the mold and combining it with the glass upper mold to form a mold, pouring the photochromic substrate solution into the mold at 20°C, curing it at 120°C for 20 h, removing the glass upper mold, and obtaining a lens with the photochromic substrate attached;

[0138] (2) Soaking the lens with the photochromic substrate obtained in step (1) in a NaOH solution (25%) at an ultrasonic power of 80 mV for 10 min, then cleaning it in an alkaline detergent for 8 min, rinsing it with clean water, and drying it to obtain a pretreated lens with the photochromic substrate;

[0139] (3) coating the photochromic coating liquid on the photochromic substrate of the lens attached with the photochromic substrate pretreated in step (2), heating in an oven at 120° C. for 1.5 h to cure and form a lens coated with a photochromic layer;

[0140] (4) coating the protective liquid on the photochromic layer of the lens coated with the photochromic layer obtained in step (2) and irradiating the lens with an ultraviolet light power of 500 mW / cm 2 UV curing for 3 s, with the oxygen content in the air lower than 6%, to obtain the primary photochromic lens

[0141] (5) Coating silicone resin on both sides of the primary photochromic lens obtained in step (4), heating in an oven at 120° C. for 2.5 h to cure and form the primary photochromic lens, thereby obtaining the photochromic lens.

[0142] Example 2

[0143] A photochromic lens, which differs from Example 1 only in that the first strengthening layer and the second strengthening layer are not provided, and other structures, materials and preparation methods are the same as those of Example 1.

[0144] Example 3

[0145] A photochromic lens, which is different from Example 1 only in that the thickness of the photochromic coating is 5 μm, and the other structures, materials and preparation methods are the same as those of Example 1.

[0146] Example 4

[0147] A photochromic lens, which is different from Example 1 only in that the thickness of the photochromic coating is 8 μm, and the other structures, materials and preparation methods are the same as those of Example 1.

[0148] Example 5

[0149] A photochromic lens, which is different from Example 1 only in that the thickness of the photochromic coating is 3 μm, and the other structures, materials and preparation methods are the same as those of Example 1.

[0150] Example 6

[0151] A photochromic lens, which is different from Example 1 only in that the thickness of the photochromic coating is 10 μm, and other structures, materials and preparation methods are the same as those of Example 1.

[0152] Example 7

[0153] A photochromic lens, which differs from Example 1 only in that resin monomer A is not added to the photochromic substrate solution as a raw material for preparing the photochromic substrate, the added amount of resin monomer B is 46 parts by weight, and the added amount of resin monomer C is 46 parts by weight. Other structures, materials and preparation methods are the same as those in Example 1.

[0154] Example 8

[0155] A photochromic lens, which differs from Example 1 only in that resin monomer B is not added to the photochromic substrate solution as a raw material for preparing the photochromic substrate, the added amount of resin monomer A is 57 parts by weight, and the added amount of resin monomer C is 35 parts by weight. Other structures, materials and preparation methods are the same as those in Example 1.

[0156] Example 9

[0157] A photochromic lens, which differs from Example 1 only in that no resin monomer C is added to the photochromic substrate solution as a raw material for preparing the photochromic substrate, the added amount of resin monomer A is 57 parts by weight, and the added amount of resin monomer B is 35 parts by weight. Other structures, materials and preparation methods are the same as those in Example 1.

[0158] Comparative Example 1

[0159] A photochromic lens, which differs from Example 1 only in that it is composed of a first strengthening layer, a lens substrate, a photochromic coating, a protective layer and a first strengthening layer arranged in sequence, and other materials, parameters and preparation methods are the same as those in Example 1.

[0160] Comparative Example 2

[0161] A photochromic lens, which differs from Example 1 only in that it is composed of a first strengthening layer, a lens substrate, a photochromic substrate, a protective layer and a first strengthening layer arranged in sequence, and other materials, parameters and preparation methods are the same as those in Example 1.

[0162] Comparative Example 3

[0163] A conventional lens, which is different from Example 1 in that a photochromic substrate, a photochromic coating and a protective layer are not provided, and other materials, parameters and preparation methods are the same as those of Example 1.

[0164] Performance Test:

[0165] (1) Color change depth: The transmittance of the lens after being exposed to ultraviolet light for 2 minutes is measured by an instrument and expressed in %. The smaller the value, the deeper the color change.

[0166] (2) Fading rate: the time it takes for the lens to fade from the darkest color to half of its transmittance after being tinted, expressed in seconds;

[0167] (3) Light transmittance: The percentage of incident light flux passing through the lens, measured by HunterLab ultrascanpro colorimeter;

[0168] (4) Friction resistance: According to the haze test method in GB / T2410, 000# steel wool is rubbed repeatedly on the lens surface for 1000 times under a gravity of 750 g. The haze value of the lens before and after friction is tested. If the change in haze value is ≤0.8, it is considered qualified, otherwise it is unqualified;

[0169] (5 Impact resistance: A steel ball impacts the lens surface three times from a height of 2 m, and observe whether the lens has cracks. If there are no obvious cracks, it is considered qualified, otherwise it is unqualified.

[0170] The lenses provided in Examples 1 to 9 and Comparative Examples 1 to 3 were tested according to the above test method. The test results are shown in Table 2:

[0171] Table 2

[0172]

[0173] It can be seen from the data in Table 2 that the photochromic lens provided by the present invention has the advantages of deep color change and fast fading rate, and will not affect the base color of the lens substrate.

[0174] Specifically, the color change depth of the photochromic lenses obtained in Examples 1 to 4 is 3.9 to 5.5%, which is a relatively deep color change depth; the fading rate is 68 to 75 seconds, which is a relatively fast fading speed; and the light transmittance is 90.5 to 92.3%. Comparing the data of Comparative Examples 1 to 2 with that of Example 1, it can be seen that the color change depth of the photochromic lenses obtained without the photochromic substrate (Comparative Example 1) and the photochromic lenses obtained without the photochromic coating (Comparative Example 2) are both relatively shallow.

[0175] Comparing the data of Comparative Example 3 and Example 1, it can be seen that conventional lenses do not have a color-changing effect.

[0176] Further comparison of the data of Example 1 and Examples 5-6 shows that if the thickness of the photochromic coating is too high, the fading rate of the photochromic lens will be slower, while if the thickness of the photochromic coating is too low, the discoloration depth of the photochromic lens will be shallower.

[0177] Finally, by comparing the data of Example 1 and Examples 7 to 9, it can be seen that the photochromic substrate preparation raw materials using only two resin monomers will also affect the color change depth and color change rate of the final photochromic lens.

[0178] The applicant declares that the present invention illustrates a photochromic lens and a method for preparing the same through the above-mentioned embodiments, but the present invention is not limited to the above-mentioned process steps, that is, it does not mean that the present invention must rely on the above-mentioned process steps to be implemented. Those skilled in the art should understand that any improvement to the present invention, equivalent replacement of the raw materials used in the present invention, addition of auxiliary components, selection of specific methods, etc., all fall within the protection scope and disclosure scope of the present invention.

Claims

1. A photochromic lens with a light transmittance of 90.5-92.3%, characterized in that: The photochromic lens comprises a first strengthening layer, a lens substrate, a photochromic substrate, a photochromic coating, a protective layer and a second strengthening layer which are arranged in sequence; The thickness of the photochromic substrate is 1-2 μm; The thickness of the photochromic coating is 5-8 μm; The thickness of the first strengthening layer and the second strengthening layer are independently 2-4 μm; The material of the lens substrate is acrylic acid; The raw material for preparing the photochromic substrate is a photochromic substrate solution, and the photochromic substrate solution includes the following components in parts by weight: Resin monomer A 40~45 parts by weight Resin monomer B 20~30 parts by weight Resin monomer C 20~30 parts by weight Color changing liquid 5~20 parts by weight Initiator 0.04~0.1 parts by weight; The color-changing liquid is SunSensors TM -MR-8 TM ; The resin monomer A is a Japanese Mitsui Chemicals MR-8A monomer, the resin monomer B is a Japanese Mitsui Chemicals MR-8B1 monomer, and the resin monomer C is a Japanese Mitsui Chemicals MR-8B2 monomer; The raw material for preparing the photochromic coating is a photochromic coating liquid, and the photochromic coating liquid comprises the following components in parts by weight: Polyol 5-15 parts by weight Isocyanate 65~75 parts by weight Color change factor 5~10 parts by weight Light stabilizer 0.5~1 parts by weight; The color changing factor is spiropyran; The raw material for preparing the protective layer is a protective coating liquid, and the protective coating liquid includes the following components in parts by weight: Reactive diluent monomer 50~70 parts by weight Oligomer 15~25 parts by weight The second surfactant 0.5-1 parts by weight Photoinitiator 0.2-0.5 parts by weight; The second surfactant includes N-methylaminopropyltrimethoxysilane and / or γ-glycidyloxypropyltrimethoxysilane; The raw materials for preparing the first strengthening layer and the second strengthening layer are both silicone resin coating liquid; The photochromic lens is prepared by the following method, which comprises the following steps: (1) Using the lens substrate as the lower mold of the mold and combining it with the glass upper mold to form a mold, pouring the photochromic substrate solution into the mold, curing and forming it, removing the glass upper mold, and obtaining a lens with the photochromic substrate attached; (2) coating the photochromic coating liquid on the photochromic substrate of the lens attached with the photochromic substrate obtained in step (1), and curing and forming the lens to obtain a lens coated with a photochromic layer; (3) coating the protective coating liquid on the photochromic layer of the lens coated with the photochromic layer obtained in step (2), and UV curing to obtain the photochromic lens; Step (3) after the UV curing, further comprises the steps of coating the surface of the formed protective layer and the surface of the lens substrate with a silicone resin coating solution, and curing and forming the coating solution.

2. The photochromic lens according to claim 1, characterized in that: The diameter of the lens substrate is 65-80 mm.

3. The photochromic lens according to claim 1, characterized in that: The center thickness of the lens substrate is 2-5 mm.

4. The photochromic lens according to claim 1, characterized in that: The edge thickness of the lens substrate is 2-15 mm.

5. The photochromic lens according to claim 1, characterized in that: The initiator includes any one of monomethyltin dichloride, dimethyltin dichloride, trimethyltin monochloride, diethyltin dichloride, dimethyltin dibromide, dibutyltin dichloride or trimethyltin monobromide, or a combination of at least two thereof.

6. The photochromic lens according to claim 1, characterized in that: The photochromic substrate solution also includes any one of an additive, a release agent or a color-correcting agent, or a combination of at least two thereof.

7. The photochromic lens according to claim 6, characterized in that: The content of the auxiliary agent added to the photochromic substrate solution is 0.1-0.5 parts by weight.

8. The photochromic lens according to claim 6, characterized in that: The additive comprises any one of a defoamer, an antioxidant or a leveling agent, or a combination of at least two of them.

9. The photochromic lens according to claim 6, characterized in that: The content of the release agent in the photochromic substrate solution is 0.05-0.1 parts by weight.

10. The photochromic lens according to claim 6, characterized in that: The release agent includes any one of isopropyl phosphate, diisopropyl phosphate or butyric acid phosphate or a combination of at least two thereof.

11. The photochromic lens according to claim 6, characterized in that: The content of the color-correcting agent in the photochromic substrate solution is 0.5 to 1 part by weight.

12. The photochromic lens according to claim 6, characterized in that: The color-correcting agent is an organic pigment.

13. The photochromic lens according to claim 1, characterized in that: The photochromic substrate solution is prepared by the following method, which comprises the following steps: (A1) mixing part of the resin monomer A and the initiator to obtain a mixture A; mixing the remaining part of the resin monomer A, the color-changing liquid, an optional auxiliary agent and an optional release agent to obtain a mixture B; (A2) Mixing the mixture A obtained in step (A1), the mixture B, the resin monomer B, the resin monomer C and an optional color correcting agent to obtain the photochromic substrate solution.

14. The photochromic lens according to claim 13, characterized in that: The mixing in step (A2) is performed under vacuum conditions.

15. The photochromic lens according to claim 13, characterized in that: The mixing temperature in step (A2) is 5-15°C.

16. The photochromic lens according to claim 13, characterized in that: The mixing time in step (A2) is 30 to 60 minutes.

17. The photochromic lens according to claim 1, characterized in that: The photochromic coating liquid further includes any one of a solvent, a leveling agent, a first surfactant or an antioxidant, or a combination of at least two of them.

18. The photochromic lens according to claim 17, characterized in that: The content of the solvent in the photochromic coating liquid is 14 to 20 parts by weight.

19. The photochromic lens according to claim 17, characterized in that: The content of the leveling agent in the photochromic coating liquid is 0.5 to 1 part by weight.

20. The photochromic lens according to claim 17, characterized in that: The content of the surfactant in the photochromic coating liquid is 0.2-0.5 parts by weight.

21. The photochromic lens according to claim 17, characterized in that: The content of the antioxidant in the photochromic coating liquid is 0.2-0.5 parts by weight.

22. The photochromic lens according to claim 1, characterized in that: The photochromic coating liquid is prepared by the following method, which comprises the following steps: (B1) dissolving a color-changing factor in a solvent to obtain a color-changing concentrate; mixing an isocyanate, a polyol, a light stabilizer, an optional leveling agent, an optional antioxidant, and an optional first surfactant to obtain a white material; (B2) Mixing the color-changing concentrated solution obtained in step (B1) with white material to obtain the photochromic coating solution.

23. The photochromic lens according to claim 22, characterized in that: The temperature for dissolving the color-changing factor in the solvent in step (B1) is 50-70°C.

24. The photochromic lens according to claim 22, characterized in that: The mixing time in step (B1) is 1 to 2 h.

25. The photochromic lens according to claim 22, characterized in that: The mixing time in step (B2) is 1 to 2 h.

26. The photochromic lens according to claim 1, characterized in that: The thickness of the protective layer is 10-20 μm.

27. The photochromic lens according to claim 1, characterized in that: The reactive diluent monomer includes any one of trimethylolpropane triacrylate, trimethylolpropane triacrylate, neopentyl glycol diacrylate, tetrahydrofuran acrylate, pentaerythritol triacrylate or pentaerythritol tetraacrylate, or a combination of at least two thereof.

28. The photochromic lens according to claim 1, characterized in that: The oligomer includes any one of bisphenol A epoxy resin, silicone epoxy resin or epoxy acrylate oligomer or a combination of at least two thereof.

29. The photochromic lens according to claim 1, characterized in that: The photoinitiator includes diphenyl (2,4,6-trimethylbenzoyl) phosphine oxide and / or bisacryloylphosphine oxide.

30. The photochromic lens according to claim 1, characterized in that: The protective coating liquid also includes a solvent.

31. The photochromic lens according to claim 30, characterized in that: The content of the solvent in the protective coating liquid is 10 to 15 parts by weight.

32. The photochromic lens according to claim 30, characterized in that: The solvent includes any one of xylene, N,N-dimethylformamide or methyl pyrrolidone, or a combination of at least two thereof.

33. The photochromic lens according to claim 1, characterized in that: The protective coating liquid is prepared by the following method, which comprises: mixing a reactive diluent monomer, an oligomer, a photoinitiator, a second surfactant and optionally a solvent to obtain the protective coating liquid.

34. The photochromic lens according to claim 33, characterized in that: The mixing time is 1 to 2 h.

35. The photochromic lens according to claim 1, characterized in that: The photochromic lens comprises a first anti-reflection film, a first strengthening layer, a lens substrate, a photochromic substrate, a photochromic coating, a protective layer, a second strengthening layer and a second anti-reflection film which are arranged in sequence.

36. The photochromic lens according to claim 1, characterized in that: The pouring temperature in step (1) is 15-20°C.

37. The photochromic lens according to claim 1, characterized in that: The curing time in step (1) is 10 to 20 hours.

38. The photochromic lens according to claim 1, characterized in that: The curing temperature in step (1) is 110-130°C.

39. The photochromic lens according to claim 1, wherein: Before the coating in step (2), the step also includes a step of pre-treating the surface of the lens with the photochromic substrate attached thereto obtained in step (1).

40. The photochromic lens according to claim 39, wherein: The surface pretreatment comprises: soaking the lens with the photochromic substrate obtained in step (1) in a sodium hydroxide solution, and then washing it in an alkaline detergent and water in sequence to complete the surface pretreatment.

41. The photochromic lens according to claim 40, characterized in that: The mass percentage of sodium hydroxide in the sodium hydroxide solution is 20-30%.

42. The photochromic lens according to claim 40, characterized in that: The immersion is performed under ultrasonic conditions.

43. The photochromic lens according to claim 42, characterized in that: The power of the ultrasound is 20-90 mV.

44. The photochromic lens according to claim 40, characterized in that: The soaking time is 5 to 20 min.

45. The photochromic lens according to claim 1, characterized in that: The curing temperature in step (2) is 110-130°C.

46. ​​The photochromic lens according to claim 1, wherein: The curing time in step (2) is 1 to 2 hours.

47. The photochromic lens according to claim 1, wherein: The UV curing time in step (3) is 2 to 5 s.

48. The photochromic lens according to claim 1, wherein: The power of the UV curing in step (3) is 400-600 mW / cm 2 .

49. The photochromic lens according to claim 1, wherein: The curing time after applying the silicone resin coating in step (3) is 2 to 3 hours.

50. The photochromic lens according to claim 1, wherein: The curing temperature after applying the organic silicone resin coating liquid in step (3) is 100-130°C.

51. A method for preparing a photochromic lens, characterized in that: The method is used for preparing the photochromic lens as described in any one of claims 1 to 50.

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