Embedded wafers and wafer coating compositions as optical articles

Abstract

An ophthalmic lens comprising an embedded functional wafer coated with a coating layer on one or both sides, and a method for manufacturing the same. The coating layer may provide adhesion between the functional wafer and the surrounding resin used to form the lens. The coating layer may also protect the functional wafer from degradation during manufacturing, such as chemical attack during thermoforming or exposure to heat. The coating layer may be applied to a flat functional sheet and then molded to a curvature matching the lens, or the coating layer may be applied to a functional wafer that is already curved. The coating layer may comprise a variety of compositions known to provide adhesion, protection from heat, and / or protection from chemicals.

Description

Technical Field

[0001] (Cross - reference to Related Applications) This application claims the benefit and priority of U.S. Provisional Application No. 63 / 494,707, entitled "Optical Articles Having Embedded Wafers and Wafer Coating Compositions", filed on April 6, 2023, which is hereby incorporated by reference in its entirety.

Background Art

[0002] Optical articles such as ophthalmic lenses often desire to have additional functions such as photochromic, electrochromic, mirror, and / or polarization functions. One known method of adding a function to such an optical article is generally to apply a functional coating to the front surface of the lens article surface by a spin - coating process. Another known method of adding a function to such an optical article is to embed a wafer providing the desired function under the front surface of the lens, or to sandwich a functional wafer between the front and back surfaces of the lens.

[0003] Optical articles such as ophthalmic lenses may also include various surface features. Examples of such surface features include bifocal, trifocal, or multifocal segmented lenses. Segmented lenses may also be called by designations such as D28, D35, or a design name. However, such lenses with surface features present a problem in that the spin - coating process of an article with surface features can affect the flow of the coating solution, thereby resulting in coating thickness non - uniformity and thus potentially non - uniform color when activated.

[0004] For example, such optical articles may be manufactured by inserting a functional film layer or wafer into a gasket and mold setup, filling the mold cavity with liquid monomers so that the monomers are on both sides of the functional wafer, and forming a bond between the wafer and the formed optical resin while polymerizing the monomers into an optical resin. Figure 1 shows an example of an ophthalmic lens in which a functional wafer 2 is sandwiched between a first layer 1 and a second layer 3 of lens material.

[0005] U.S. Patent Publication 2007 / 0122626, which is incorporated herein by whole reference in its entirety, describes a method for manufacturing a photochromic cast lens having improved photochromic properties, such as by using a photochromic film having at least one protective layer. The protective layer should have good "compatibility" with the lens casting material in order to provide sufficient adhesion without being damaged by chemicals or other factors during the manufacturing process. Therefore, the protective layer should ideally possess both optical quality and the ability to bond with the lens casting material.

[0006] Obtaining a protective layer of such quality can be difficult. A protective layer with sufficient protective properties and resistance to chemical attack by, for example, lens casting materials may be more inert and therefore may not provide sufficient adhesion to the polymerized casting resin. On the other hand, a protective layer that is well compatible for good bonding with the casting resin may be susceptible to chemical attack by aggressive casting resin monomers, resulting in a cloudy and / or optically opaque finish.

[0007] Proper adhesion between the protective layer and the casting resin is crucial in lens manufacturing, as semi-finished lenses may undergo numerous surfacing and processing steps in the Rx Surfacing Lab, potentially exposing them to different mechanical, chemical, and thermal factors. Without proper adhesion, the protective layer and casting resin may separate under such demanding processing steps and conditions. Furthermore, proper adhesion is essential for the long-term durability of ophthalmic lenses.

[0008] Many photochromic lenses may rely on spin coating technology, where the photochromic coating is applied to the front surface of the lens. The photochromic coating layer often requires a thickness of more than 10 microns for proper photochromic performance. When optical articles have surface features such as segmented lenses, achieving a uniform coating thickness is difficult, and therefore achieving uniform color is difficult. Photochromic lenses with such surface features can also be manufactured by blending a photochromic dye into the lens resin using a process called in-mass photochromism. Lenses manufactured using such a process without control of the host environment for photochromic dye activation may activate to a brighter color and fade at a slower rate when exposed to an activating light source.

[0009] Therefore, an intermediate layer coating is needed between the cast resin and the protective layer of the functional wafer, which provides protection to the functional wafer and / or functions as a good adhesive layer between the cast resin and the functional wafer. Ideally, the intermediate layer coating exhibits both protective and adhesive properties, resulting in uniform coating thickness and uniform color when activated in lenses with surface characteristics. [Overview of the Initiative]

[0010] This specification discloses various embodiments of optical articles, such as ophthalmic lenses, having embedded functional wafers coated with a protective coating layer on one or both sides.

[0011] This specification also discloses various embodiments of optical articles, such as ophthalmic lenses having surface features such as multifocal lenses, in which a functional wafer having a protective coating layer formed on one or both sides is embedded inside.

[0012] In exemplary embodiments, the functional wafer may include polarizing media, decorative media, coloring media, electrochromic media, mirror media, embedded electronic devices, patterned films, planar optics, embedded optical filters, holographic optical elements, and / or photochromic media.

[0013] In an exemplary embodiment, the functional wafer may be substantially flat when the coating layer is applied. In another exemplary embodiment, the functional wafer may be curved when the coating layer is applied.

[0014] In exemplary embodiments, the coating layer may be applied to a functional wafer using a variety of methods, including but not limited to immersion coating, spin coating, spray coating, roll coating, sheet coating, printing, and gravure coating.

[0015] In exemplary embodiments, one or more coating layers may provide improved adhesion between the functional wafer and the surrounding lens material, such as a resin.

[0016] In exemplary embodiments, one or more coating layers may protect the functional wafer from degradation during the lens formation process due to chemical attack or other factors.

[0017] In an exemplary embodiment, only one side of the functional wafer may be coated with a protective coating layer. In another exemplary embodiment, both sides of the functional wafer may be coated with a protective coating layer, with a first surface of the functional wafer being coated with a first coating layer and a second surface of the functional wafer being coated with a second coating layer.

[0018] In exemplary embodiments, the functional wafer and coating layer may have substantially the same curvature as the lens material in which they are embedded.

[0019] In an exemplary embodiment, the coating can function as both a barrier layer of the functional film material and an adhesive layer between the film layer and the surrounding lens resin.

[0020] In an exemplary embodiment, the coating can have crack resistance properties that enable the processing of the functional film from a flat configuration to a curved configuration for lens applications.

[0021] In an exemplary embodiment, the coating can be in a partially cured or in - process - of - curing state on the film to improve the formability during the thermoforming of the wafer.

[0022] In an exemplary embodiment, dual curing of thermal curing and photo - curing can be utilized, and by making the coating in a partially cured state through a thermal process, sufficient adhesion to the film and thermoformability are provided.

[0023] In an exemplary embodiment, after being applied to the film, the coating can be exposed to a photo - curing source such as low - dose UV, LED, or visible light.

[0024] In an exemplary embodiment, the formable coated film can have sufficient flexibility such that no cracks occur in the wafer during or after thermoforming, even when coating a flat film or wafer.

[0025] In an exemplary embodiment, the film thickness can be between about 0.1 millimeter and 2 millimeters.

[0026] In an exemplary embodiment, the coating can have a thickness between about 0.5 micron and 20 microns.

[0027] In an exemplary embodiment, the film can be polycarbonate, and the lens material can be formed from a liquid monomer.

[0028] In an exemplary embodiment, the coated film can be pre - formed before injection molding.

[0029] In an exemplary embodiment, the coating can be applied to the film using methods such as spin coating, roll-to-roll coating (e.g., gravure or slot die coating), and the like, which are not limited thereto.

[0030] In an exemplary embodiment, a UV curable coating having a thickness varying from about 0.8 microns to 1.4 microns can be applied using a gravure coater.

[0031] In an exemplary embodiment, a microgravure cylinder having 150 or 180 lines per inch, having a helical pattern and a 45-degree engraving axis, and capable of transferring a coating volume of about 6.0 to 14.0 cubic centimeters per square meter may be used.

[0032] In an exemplary embodiment, excess coating can be trimmed by a metal or plastic doctor blade or the like.

[0033] In an exemplary embodiment, the thickness of the coating can be uniform across the entire width of the substrate.

[0034] In an exemplary embodiment, after application, the wet coating can be dried and / or UV cured.

[0035] In an exemplary embodiment, the coating can be applied to the film in the form of a flat wafer or a shaped (e.g., curved) wafer.

[0036] In an exemplary embodiment, a liquid containing a solvent can be applied to the film, and a coating layer can be formed on the film by evaporation of the solvent.

[0037] In some embodiments, the techniques described herein relate to a method for forming a cast ophthalmic lens, comprising forming a coated functional wafer by coating a first surface and a second surface of a functional wafer with a coating composition, placing the coated functional wafer in a mold, applying a resin to the first and second surfaces of the coated functional wafer, and curing the resin and the coated functional wafer to form a cast ophthalmic lens.

[0038] In some embodiments, the techniques described herein relate to methods for bending functional wafers.

[0039] In some embodiments, the techniques described herein relate to methods for ensuring that functional wafers are flat.

[0040] In some embodiments, the techniques described herein further include a method for thermoforming a coated functional wafer to impart curvature to the coated functional wafer.

[0041] In some embodiments, the techniques described herein relate to a method for a coating composition comprising a polymer formed from a combination of one or more hydrolyzed siloxanes having at least three functional groups, and one or more solvents.

[0042] In some embodiments, the techniques described herein relate to a method for which a coating composition further comprises one or more adhesion promoters, UV absorbers, colorants, or bluing agents.

[0043] In some embodiments, the techniques described herein relate to methods in which the polymer is contained in a coating composition at a ratio of 20 to 95% relative to the solids weight.

[0044] In some embodiments, the techniques described herein relate to methods comprising a combination of at least three functional groups, each consisting of a methacrylate and either a hydroxyl or amine functional group.

[0045] In some embodiments, the techniques described herein relate to a method for a coating composition comprising a crosslinked solvent-resistant polymer network formed from at least three functional groups and a flexible film-forming transparent polymer.

[0046] In some embodiments, the techniques described herein relate to a method for selecting at least three functional groups from the group consisting of hydroxyl, amine, imine, and methacrylate.

[0047] In some embodiments, the techniques described herein relate to methods for which a flexible film-forming transparent polymer comprises thermoplastic polyurethane and / or cellulose acetate butyrate.

[0048] In some embodiments, the techniques described herein relate to a method for a coating composition further comprising one or more photochemical initiators, adhesion promoters, UV absorbers, colorants, or bluing agents.

[0049] In some embodiments, the techniques described herein relate to a method for a coating composition comprising an acrylate monomer, a polymer, and one or more solvents.

[0050] In some embodiments, the techniques described herein relate to methods for which the resin comprises polycarbonate.

[0051] In some embodiments, the techniques described herein relate to a method for selecting a functional wafer from the group consisting of photochromic wafers, electrochromic wafers, mirror wafers, polarizing wafers, holographic optical element wafers, patterned film wafers, optical filter wafers, and colored wafers.

[0052] In some embodiments, the techniques described herein relate to a method for forming a cast ophthalmic lens, comprising forming a coated functional wafer by coating a functional wafer with a coating composition using a gravure cylinder, placing the coated functional wafer in a mold, applying a resin to the coated functional wafer, and curing the resin and the coated functional wafer to form a cast ophthalmic lens.

[0053] In some embodiments, the technology described herein relates to a method including a microgravure cylinder in which the gravure cylinder has 150 or 180 lines per inch.

[0054] In some embodiments, the techniques described herein relate to a method by which a gravure cylinder includes a helical pattern.

[0055] In some embodiments, the techniques described herein further include a step of trimming off excess coating to provide uniformity of coating thickness.

[0056] In some embodiments, the techniques described herein relate to coating compositions that promote adhesion and protection to functional wafers, comprising an acrylate monomer, a polymer, and one or more solvents.

[0057] In some embodiments, the techniques described herein relate to coating compositions that promote adhesion and protection to functional wafers, comprising a combination of two or more compounds comprising a silane having formula (I), (II) and a methacrylic acid derivative having formula (III), wherein R is a methyl group, an ethyl group, a propyltrimethoxysilyl group, or a propyltriethoxysilyl group, R1 is a hydrocarbon group having 1 to 4 carbon atoms, X is a hydrolyzable group comprising an alkoxy group, an acyloxy group, a halogen, or an amine, Y is a hydrogen atom or an aminoalkyl group, and Z is a glycidoxy group or an epoxycyclohexyl group, comprising one or more additives and two or more solvents.

[0058] In some embodiments, the techniques described herein relate to coating compositions comprising a solid crosslinkable and solvent-resistant polymer network of 20 to 95% by weight.

[0059] In some embodiments, the techniques described herein relate to coating compositions comprising at least three active functional groups configured to promote covalent bonding of an optical article with an optical resin.

[0060] In some embodiments, the techniques described herein relate to coating compositions comprising an active functional group configured to promote covalent bonding with a resin, which is a hydroxyl group, an amine group, an imine group, or a methacrylate group.

[0061] In some embodiments, the techniques described herein relate to coating compositions in which methacrylate groups are configured to promote covalent bonding with poly(allyl dicarbonate) resins.

[0062] In some embodiments, the techniques described herein relate to coating compositions in which hydroxyl groups or amine groups are configured to promote covalent bonding with urethane resins.

[0063] In some embodiments, the techniques described herein relate to coating compositions comprising one or more additives such as adhesion promoters, UV absorbers, colorants, or bluing agents.

[0064] In some embodiments, the techniques described herein relate to coating compositions comprising one or more additives in an amount of 1 to 5% on a solid weight basis.

[0065] In some embodiments, the technology described herein relates to a coating composition for optical wafers, comprising an acrylate derivative, a transparent polymer, and one or more additives, wherein the coating composition promotes adhesion and protection of optical articles to functional wafers.

[0066] In some embodiments, the techniques described herein relate to coating compositions comprising two or more solvents.

[0067] In some embodiments, the techniques described herein relate to coating compositions comprising an acrylate derivative of 2-hydroxyethyl acrylate or an ester derivative of pentaerythritol.

[0068] In some embodiments, the techniques described herein relate to coating compositions further comprising pentaerythritol ester derivatives, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, pentaerythritol triacrylate, or pentaerythritol tetraacrylate.

[0069] In some embodiments, the techniques described herein relate to coating compositions comprising an acrylate derivative in an amount of 20 to 95% by weight of a solid crosslinked polymer.

[0070] In some embodiments, the techniques described herein relate to coating compositions in which the transparent polymer comprises a thermoplastic polyurethane polymer, a thermoplastic polyester polymer, a cellulose acetate butyrate (CAB) polymer, or a vinyl chloride-vinyl acetate copolymer.

[0071] In some embodiments, the techniques described herein relate to coating compositions comprising a transparent polymer in an amount of 1 to 20% by solids weight.

[0072] In some embodiments, the techniques described herein relate to coating compositions configured such that a transparent polymer forms a flexible film.

[0073] In some embodiments, the techniques described herein relate to coating compositions in which the transparent polymer has a tensile stress of about 20 megapascals or more.

[0074] In some embodiments, the techniques described herein relate to coating compositions comprising one or more additives such as adhesion promoters, UV absorbers, colorants, or bluing agents.

[0075] In some embodiments, the techniques described herein relate to coating compositions further comprising one or more additive initiators that initiate covalent bonding between an acrylate derivative and an optical resin.

[0076] In some embodiments, the techniques described herein relate to coating compositions in which the initiator further comprises a photochemical initiator, a thermal initiator, a blend of photochemical initiators, a blend of photoinitiators, or a blend of photochemical and thermal initiators.

[0077] In some embodiments, the techniques described herein relate to coating compositions that are crack-resistant under stretching.

[0078] In some embodiments, the techniques described herein relate to coating compositions that are suitable for the thermoforming conditions of functional wafers. [Brief explanation of the drawing]

[0079] These and other embodiments, features, and advantages of the present invention are apparent and clarified from the following description of embodiments of the present invention with reference to the accompanying drawings.

[0080] [Figure 1] Figure 1 is a cross-sectional view of a multilayer lens having a functional wafer embedded in a cast resin.

[0081] [Figure 2] Figure 2 is a cross-sectional view of a multilayer lens according to one embodiment of the present invention, having a dual-function coating composition between the top surface of a functional wafer and a cast resin, and between the bottom surface of a functional wafer and a cast resin.

[0082] [Figure 3]Figure 3 is a cross-sectional view of a moldable functional wafer, according to one embodiment of the present invention, in which a coating composition is applied to both sides.

[0083] [Figure 4] Figure 4 is a cross-sectional view of an exemplary process for forming a coated moldable functional wafer from a coated functional sheet wafer according to one embodiment of the present invention.

[0084] [Figure 5] Figure 5 is a cross-sectional view of an exemplary process for forming a coated moldable functional wafer from two coated protective sheets or layers, according to one embodiment of the present invention.

[0085] [Figure 6] Figure 6 is a table showing the optical properties, adhesion, and environmental test results of examples of coated photochromic wafers and lenses according to a specific embodiment of the present invention.

[0086] [Figure 7] Figure 7 is a table showing specific optical properties, adhesion, and environmental test results for examples of coated polarizing wafers and lenses according to a particular embodiment of the present invention.

[0087] [Figure 8] Figure 8 is a top view showing an example of a multifocal lens according to a specific embodiment of the present invention. [Modes for carrying out the invention]

[0088] Specific embodiments of the present invention will be described with reference to the accompanying drawings. However, the present invention can be carried out in many different forms and should not be construed as being limited to the embodiments described herein. Rather, these embodiments are provided to make this disclosure sufficient and complete and to allow those skilled in the art to fully understand the scope of the invention. The terms used in the detailed description of the embodiments shown in the accompanying drawings are not intended to limit the invention. In the drawings, the same number refers to the same element.

[0089] In this specification, when the terms “approximately,” “around,” or “about” are used in reference to a value, it should be understood that they mean within ±10% of the stated value (both greater and less).

[0090] While different embodiments may be described herein, it is particularly intended that any features of the different embodiments can be combined with each other in any combination. In other words, features of the different embodiments can be mixed and combined with each other. Therefore, even if not explicitly shown, it is the intention of this specification to encompass all combinations of features of the different embodiments.

[0091] This specification discloses various exemplary embodiments of ophthalmic lenses having embedded functional wafers to which a coating may be applied to one or both sides to form a protective layer. The coating can serve a dual function: providing adhesion between the embedded wafer and the surrounding lens material (e.g., resin), and protecting the embedded wafer from degradation or other defects caused by chemicals used during the manufacturing process.

[0092] Functional wafers can provide a wide range of functions for ophthalmic lenses. Examples include polarizing media, decorative media, coloring media, tinting media, photochromic media, photoelectric media, and mirror media. Therefore, it should be understood that the systems, apparatus, and methods shown and / or described herein can be used in combination with a wide range of functional wafers or layers applicable to a wide variety of optical articles.

[0093] The coatings may comprise a variety of compositions that can provide a wide range of benefits, including but not limited to improved adhesion and / or resistance to chemical attack. For example, the coatings may provide optical quality, high clarity, and a lack of haze. The coatings may be formulated to provide good adhesion to a variety of optical films, including but not limited to polycarbonate, PMMA, polyester, and TAC.

[0094] The coating may contain, for example, about 20% to 95% solids by weight of a crosslinked solvent-resistant polymer network formed from at least three or more functional components. The polymer may be inherently thermosetting. The polymer may be formed from hydrolyzed siloxanes, acrylates, methacrylates, etc. The crosslinked polymer may contain active functional groups that promote covalent bonding to the resin, such as functional groups including hydroxyl, amine, imine, and methacrylate.

[0095] In exemplary embodiments, a combination of methacrylate and either a hydroxyl or amine functional group may be used. The methacrylate group helps bond the embedded wafer, while the hydroxyl / amine group promotes bonding to the urethane resin. Such exemplary coatings may also contain about 1% to 5% by solids weight of other additives such as adhesion promoters, UV absorbers, colorants, and bluing agents. Furthermore, a blend of two or more solvents may be added to form a coating solution of about 3% to 20% of the above solid composition, which is then applied to a functional film.

[0096] As another example, the coating may contain approximately 20% to 95% solids by weight of a crosslinked solvent-resistant polymer network formed from at least three functional components, combined with approximately 1% to 20% solids by weight of a flexible film-forming transparent polymer. The polymer may be inherently thermoplastic. The tensile strength of the polymer film may be 20 megapascals or more.

[0097] Exemplary polymers may include thermoplastic polyurethane (PU), thermoplastic polyester, cellulose butyrate esters such as cellulose acetate butyrate (CAB), and vinyl chloride-vinyl acetate copolymers. Such exemplary coatings may also contain approximately 1% to 10% by solids weight of other additives, such as initiators (e.g., in the case of acrylate / methacrylate polymers), adhesion promoters, UV absorbers, colorants, and bluing agents.

[0098] The coating may have properties sufficient to act as a barrier layer, thereby eliminating chemical attack from various optical monomers known to be used in the manufacture of cast lenses. The coating may provide a strong bond or adhesion between the surrounding resin formed from the cast optical monomers and the wafer. The coating may have high surface energy to eliminate the formation of bubbles or other defects on the wafer surface during the casting process. The coating may also provide thermoformability.

[0099] The method of applying a coating to one or both sides of a functional film or wafer may vary in different embodiments. For example, the coating may be applied using various methods such as immersion coating, spin coating, spray coating, roll coating, sheet coating, printing, and gravure coating. The coating may be applied to the functional film or wafer before it is formed, for example, while the functional film or wafer is in a substantially flat configuration, and the resulting coated film or wafer is then formed or shaped into a final shape for use in lenses. Alternatively, the coating may be applied to the functional film or wafer after it has already been shaped (for example, into a curved configuration).

[0100] The coatings may include, but are not limited to, poly(allyl dicarbonate) (commonly known as "ADC" or "CR-39"), and may be formulated to bond with many optical resins commonly used in the optical lens industry. Additional exemplary optical resins to which the coatings may bond include urethane, urea-urethane, and thio-urethane resin systems, which are commercially available under trade names such as "RAVolution," "Trivex," "MR-8," "MR-10," and "MR174." Various other optical resins known in the art may also be used in combination with the systems and methods shown and / or described herein.

[0101] In general, the systems and methods shown and / or described herein may be used to introduce one or more intermediate layers into a lens by embedding a coated wafer beneath the surface of the lens. Thus, the embedded wafer may generally be located beneath the front of the lens. In some embodiments, the embedded wafer may be surrounded on both sides by the lens, with the embedded wafer sandwiched between a front lens layer and a back lens layer. The lens layers may include a cast resin layer formed from a polymer polymerized from a liquid monomer.

[0102] The wafer may have substantially the same curvature as the front surface of the lens, and one or both sides of the wafer may be coated with one or more compositions that form one or more protective layers separating the wafer from the surrounding lens material.

[0103] The method by which ophthalmic lenses, including coated wafers, may be formed may vary in different embodiments. In a first example, the coating composition may be applied to both sides of a functional wafer, previously shaped to conform to the same curvature as the front mold, using a variety of coating methods, including those previously listed herein. In a second example, the coating composition may be applied to both sides of a functional flat sheet using a variety of methods, such as spray coating, roll coating (i.e., wire rod, Meyer rod coating, gravure coating, etc.). In a third example, the coating composition may be applied to one side of an optical protective layer before forming a functional laminate. The protective layer may be in sheet or roll form.

[0104] In embodiments where the coating is applied to a flat or substantially flat wafer or sheet, the coated wafer or sheet can then be formed into a desired shape for stretching from a flat wafer or sheet to a curved wafer or sheet using various methods or processes, such as a thermoforming process. Therefore, the coating composition may be compatible with such thermoforming by exhibiting, for example, crack resistance and / or adhesion recovery.

[0105] Specific exemplary embodiments are described further below. However, it should be understood that any features from any of the embodiments can be mixed and matched with each other in any combination. Therefore, the present invention should not be limited to these embodiments alone, but rather to a broader combination thereof.

[0106] Figures 2–5 show exemplary ophthalmic lenses and methods for forming ophthalmic lenses, including a coated functional layer embedded within the lens body. The coating can provide both protective and adhesive functions. The coating layer can be introduced onto a functional wafer, and the coated functional wafer can be formed into an optical article by embedding it in an optical resin.

[0107] Figure 2 shows an exemplary embodiment of an ophthalmic lens 10, which includes an embedded functional wafer 16 coated with a first coating layer 18 on a first side and a second coating layer 20 on a second side. In the exemplary embodiment shown in Figure 2, it can be seen that the front surface of the wafer 16 may be coated with the first coating layer 18 and the back surface of the wafer 16 may be coated with the second coating layer 20. However, it should be understood that in some embodiments, only one of the surfaces of the wafer 16 may be coated (for example, only the front surface or only the back surface may be coated). As shown in Figure 2, the front and back surfaces of the coated functional wafer 16 may have the same curvature as the front and back surfaces of the lens 10.

[0108] Continuing to refer to Figure 2, it can be seen that the functional wafer 16 may be coated with a coating layer 18 on its front surface and a coating layer 20 on its back surface. In some exemplary embodiments, the ophthalmic lens 10 may be formed by embedding the functional wafer 16, which is coated on both the front and back surfaces, beneath the front resin layer 12 of the lens 10. In some examples, the ophthalmic lens 10 may be formed by embedding the functional wafer 16, which is coated on both the front and back surfaces, between the front resin layer 12 and the back resin layer 14 of the lens 10, as shown in Figure 2.

[0109] In some examples, functional wafers may include, but are not limited to, photochromic wafers, photoelectric wafers, electrochromic wafers, holographic optical element wafers, mirror wafers, embedded electronic devices, patterned film wafers, embedded optical filters, and / or polarizing wafers, or combinations thereof. In some examples, additionally or alternatively, functional wafers may have, but are not limited to, other properties such as anti-reflective properties, mirror properties, hydrophobic properties, hydrophilic properties, and / or anti-fogging properties, or any combination of the aforementioned properties.

[0110] The front resin layer 12 and back resin layer 14 of the lens 10 may include cast resin layers formed from polymers polymerized from liquid monomers. In some examples, coating layers 18 and 20 may function as protective layers for the functional wafer 16 and / or as adhesive layers to the functional wafer 16. In some examples, coating layers 18 and 20 may provide adhesion to both the functional wafer 16 and the cast resin layers 12 and 14 of the lens 10.

[0111] Various methods can be used to coat functional wafers with a coating layer. In some examples, a coated functional wafer may be formed by applying a coating layer to one or both sides of a functional wafer having the same front and back surface curvature as the front and back lens molds. In such examples, exemplary coating methods may include, for example, immersion coating, spin coating, printing, gravure coating, or spray coating.

[0112] The functional wafer 16 may be a photochromic and / or polarizing functional wafer, may contain multiple layers, may have the same front and back surface curvature as the front and back lens molds, and coating layers 18 and 20 may be applied to the front and back of the wafer 16. Figure 3 shows an exemplary embodiment of a wafer 16 coated with first and second coating layers 18, 20, where the wafer 16 and layers 18, 20 are each curved before being encapsulated in resin to form the lens 10.

[0113] In other exemplary embodiments, a coated functional wafer may be formed by applying coating compositions 18, 20 to both sides of a functional flat sheet 16. In such exemplary embodiments, the functional flat sheet 16 may be cut and shaped after coating to generate the front and back surface curvatures of the functional wafer 16. In such a process, the coated functional flat sheet 16 may undergo a molding process, such as a thermoforming process, to stretch or otherwise adjust its shape from a flat wafer to a curved wafer 16 having the same front and back surface curvatures as the front and back lens molds.

[0114] In such thermoforming processes, the coating can exhibit strong crack resistance and adhesion recovery when a coated functional flat sheet is transformed from a flat configuration to a curved configuration. In such examples, some non-limiting coating methods may include, for example, spray coating, dip coating, spin coating, printing, gravure coating, or roll coating (commonly known as wire rod or Meyer rod coating).

[0115] Figure 4 shows an exemplary method for first coating a functional wafer 16 in a flat form (e.g., a sheet) and then shaping the resulting coated wafer to a desired curvature. As seen in Figure 4, the functional flat sheet 16 may be coated with coating layers 18, 20 on its front and back surfaces. The coated functional sheet 16 may be cut and shaped to produce the front and back surface curvatures of the coated functional wafer 16. The functional wafer 16 may be a photochromic and / or polarizing functional wafer and may contain multiple layers.

[0116] In some other examples, a coated functional wafer 16 may be formed by first applying a coating composition to the top surface of a first protective layer and the bottom surface of a second protective layer. Next, the protective layers may be laminated with the functional layers to form a functional flat sheet, and then the functional flat sheet may be cut and shaped as needed to generate the front and back surface curvatures of the functional wafer. In such a process, the coated functional flat sheet may be stretched from a flat wafer to a curved wafer having the same front and back surface curvatures as the front and back lens molds through a thermoforming process. In some examples, the protective layers may be in sheet or roll form.

[0117] Some non-limiting coating methods used to coat a protective layer may include, for example, gravure, slot die, and roll coating by flow coating. U.S. Patent Publication 2013 / 0004775, whose entire contents are incorporated into this application, demonstrates the formation of such a photochromic functional wafer.

[0118] In this example, a gravure coater may be used to apply a UV-curable coating to a functional wafer 16. The coating thickness may vary in different examples, ranging from approximately 0.8 microns to 1.4 microns, but not limited to this range. The gravure coater may include a cylinder (e.g., a gravure cylinder) having multiple cells capable of transferring a desired amount of coating onto the substrate.

[0119] The gravure cell pattern, volume, and engraving axis can vary in different examples. In some examples, the gravure cell pattern, volume, and / or engraving axis can be matched to appropriate coating solid content concentration and viscosity to achieve the desired thickness and optical quality.

[0120] For example, a microgravure cylinder may be used that has 150 or 180 lines per inch, has a helical, trihelical, or honeycomb pattern, and has a 45-degree engraving axis. Such a microgravure cylinder may be able to transfer a coating volume of about 6.0 to 14.0 cubic centimeters per square meter. Excess coating may be trimmed with a metal or plastic doctor blade, etc., to achieve uniformity of coating thickness across the entire width of the substrate. If the coating application is successful, the wet coating may be dried and / or UV cured. Such an application method may provide a more economical way to expand the coating applications discussed herein for optical and other purposes, compared to, for example, a spin coating process.

[0121] As shown in Figure 5, the top surface of the first protective layer 22 and the bottom surface of the second protective layer 23 may be coated with coating layers 18 and 20. The coated protective layers 22 and 23 may be laminated with a functional layer to form a functional flat sheet 16, which may be cut and shaped to generate the surface curvature of the front and back surfaces of the functional wafer 16.

[0122] The following paragraphs describe exemplary embodiments of coating compositions, including "Coating Composition A" and "Coating Composition B." However, it should be understood that the systems and methods shown and / or described herein may be used with a wide range of coating compositions, including but not limited to Coating Compositions A and B described below.

[0123] Coating composition A may provide high transparency and cloud-free optical quality. Coating composition A may also provide good adhesion to a variety of plastic optical films, including but not limited to polycarbonate, P-millimeter A, polyester, and TAC. Coating composition A may also have sufficient chemical properties to function as a barrier layer that eliminates chemical attack from different optical monomers used when manufacturing lenses by casting methods.

[0124] Furthermore, coating composition A may provide a strong bond between the wafer and the resin formed from the cast optical monomer. Additionally, coating composition A may have high surface energy to eliminate the formation of bubbles on the wafer surface when casting with the optical monomer. Coating composition A can be used as a wafer coating for manufacturing cast optical lenses with embedded functional wafers. Coating composition A can be applied to molded functional wafers by dipping, spin coating, or spray coating processes, as shown in Figure 3.

[0125] Coating composition B may possess all the properties of coating composition A described in the previous paragraph. However, coating composition B may also possess thermoformability. Therefore, coating composition B having thermoformability may be applied to a flat film surface in coating processes including, but not limited to, roll coating or sheet coating processes, and may also be applied in dipping coating, spin coating, or spray coating processes, and may undergo a thermoforming process without exhibiting cracking. Coating composition B may be used as a wafer coating for manufacturing cast optical lenses having embedded functional wafers. Exemplary wafers that can be prepared with coating composition B are shown in Figures 3-5.

[0126] Therefore, it should be understood that coating composition A may be best suited for coating a pre-formed, curved functional wafer 16, as shown in Figure 3. Coating composition B may be best suited for coating a flat functional sheet 16 that is formed to curvature after coating, as shown in Figures 4-5. However, it should be understood that either coating composition A or coating composition B may be used in any of the processes shown in Figures 3-5.

[0127] Coating compositions A and B may include general-purpose coating compositions for application to wafers and bonding to many optical resins used in the optical lens industry, such as poly(allyl dicarbonate) with a refractive index (RI) of 1.50, commonly known as ADC or CR-39, and urethane, urea-urethane, and thio-urethane resin systems with different refractive indices such as 1.50, 1.53, 1.55, 1.56, 1.60, 1.67, and 1.74. These resins are commercially available under the brand names RAVolution, Trivex, MR-8, MR-10, and MR174.

[0128] In exemplary embodiments, coating composition A may comprise at least the following components 1 and 2.

[0129] Component 1 of coating composition A may contain 20-95% by solids weight of a crosslinkable, solvent-resistant polymer network formed from three or more functional components. The polymer is inherently thermosetting. Two exemplary resin systems may include polymers formed from hydrolyzed siloxanes and acrylate / methacrylates. The crosslinkable polymer contains active functional groups that promote covalent bonding with monomers added to the mold to form an optical article resin after curing.

[0130] Exemplary functional groups of crosslinked polymers may include hydroxyl, amine, imine, and methacrylate. The most preferred functional groups of crosslinked polymers are combinations of methacrylate and either a hydroxyl or amine functional group. The methacrylate functional group can promote covalent bonding between the embedded wafer and the ADC resin, while the hydroxyl or amine functional groups of the embedded wafer can promote covalent bonding to the urethane resin.

[0131] The siloxane coating composition may consist of the following: 1) Aminoalkylalkoxysilanes (Formulation I) such as N-(trimethoxysilylpropyl)ethylenediamine, N-(dimethoxymethylsilylpropyl)-ethylenediamine, aminopropyltrimethoxysilane, and aminopropyltriethoxysilane, are represented by the following formula (Formulation I). In the formula JPEG2026516602000002.jpg2039, X represents a hydrolyzable group, usually an alkoxy, acyloxy, halogen, or amine, Y is hydrogen or an aminoalkyl group, and R 1 It is a hydrocarbon group having 1 to 4 carbon atoms. 2) Epoxyalkylalkoxysilanes such as γ-glycidoxypropyltrimethoxysilane and γ-glycidoxypropyltriethoxysilane (Formulation II), as shown below. In formula JPEG2026516602000003.jpg1841, X represents a hydrolyzable group, usually an alkoxy, acyloxy, halogen, or amine, Z is a glycidoxy group or epoxycyclohexyl group, and R 1 It is a hydrocarbon group having 1 to 4 carbon atoms. In formulations I and II, the hydrolyzable group X may be partially or completely hydrolyzed when forming the coating solution. 3) Derivatives of methacrylic acid such as 3-(trimethoxysilyl)propyl methacrylate (Formulation III), shown below. In formula JPEG2026516602000004.jpg2729, R may be a methyl, ethyl, propyltrimethoxysilyl, or propyltriethoxysilyl functional group.

[0132] The second component 2 of coating composition A may contain 1 to 5% by solids of other additives such as adhesion promoters, UV absorbers, colorants, or bluing agents.

[0133] A blend of two or more solvents can be added to form a coating solution from coating composition A with a solid content of 3-20%. Coating composition A can be applied in the form of a layer on a functional wafer, as shown in Figure 2.

[0134] Coating composition B may contain at least the following components 3, 4, and 5.

[0135] Component 3 of coating composition B may comprise 20 to 95% by weight of a crosslinked solvent-resistant polymer network formed from three or more functional groups. The polymer may be inherently thermosetting. The polymer may be formed from functional acrylates and methacrylates. The crosslinked polymer may contain active functional groups that promote covalent bonding with monomers added to the mold to form an optical article resin after curing. Functional groups may include hydroxyl, amine, imine, and methacrylate. In preferred exemplary embodiments, a combination of methacrylate and either a hydroxyl or amine functional group may be utilized.

[0136] Methacrylate functional groups can promote covalent bonding between the embedded wafer and the ADC resin, while hydroxyl or amine functional groups of the embedded wafer can promote covalent bonding to the urethane resin. Non-limiting examples of acrylate monomers may include hydroxyacrylates such as 2-hydroxyethyl acrylate, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, pentaerythritol triacrylate, and pentaerythritol tetraacrylate (PETA) esters.

[0137] Component 4 of coating composition B may contain 1 to 20% by weight of a flexible film-forming transparent polymer. The polymer may be intrinsically thermoplastic. The tensile strength of the polymer film may be 20 megapascals or more. Non-limiting examples of these polymers may include, but are not limited to, thermoplastic polyurethane (PU), thermoplastic polyester, cellulose butyrate esters such as cellulose acetate butyrate (CAB), and vinyl chloride-vinyl acetate copolymers. In preferred exemplary embodiments, the thermoplastic polymer may include CAB and PU.

[0138] The CABs used in this application may have a hydroxyl level exceeding 1.5% and a melting point exceeding 130 degrees. CAB-381-20 may have a hydroxyl level of 1.8% and a melting point in the range of 195-205 degrees. CAB-531.1 may have a hydroxyl level of 1.7% and a melting point in the range of 135-150 degrees.

[0139] Component 5 of coating composition B may contain 1 to 10% by solids of other additives, such as initiators, adhesion promoters, UV absorbers, colorants, or bluing agents, in the case of acrylate / methacrylate polymers.

[0140] Examples of initiators that may be used in coating composition B may include photochemical initiators, thermal initiators, blends of photochemical initiators, or blends of photochemical and thermal initiators. Photochemical initiators that may be used in coating composition B may have absorption peaks at UV wavelengths, such as alpha-hydroxyketophenones such as benzophenone, hydroxyacetophenone, phosphine oxides, and bisacylphosphine oxide photoinitiators. Examples of alpha-hydroxyketones may include Irgacure 651, Irgacure 184, Irgancure 2959, and Darocure 1173. Examples of bisacylphosphine oxide initiators may include bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, which is commercially available as Omnirad 819 or Irgacure 819 and is activated in the longer UVA wavelengths of UV light and in the near-visible region above 430 nanometers. Blends of photoinitiators may be used, such as a blend of Irgacure 184 and Darocure 1173, a blend of Irgacure 184 and benzophenone, and a blend of Irgacure 819 and Darocure 1173. In preferred examples, the photoinitiators may be alpha-hydroxy ketones and bisacylphosphine oxides. In another preferred example, the initiator may be an alpha-hydroxy ketone system. In yet another preferred example, Darocure 1173 may be used.

[0141] Thermal initiators may also be used in addition to photoinitiators to provide UV and thermal curing to the coating. One method is to expose the coating to UV for initial curing, and then achieve additional thermal curing by exposing the coating to high temperatures, such as by using an oven. Thermal initiators may include peroxides that are stable at room temperature, such as benzoyl peroxide, dicyclohexyl peroxydicarboxylic acid, tert-butyl peroxybenzoate, and tert-butyl peroxide.

[0142] An exemplary level of photoinitiator used in coating composition B may be between approximately 1% and 10%, for example, between approximately 3% and 5%.

[0143] The following and Figures 6-7 show several synthesis examples illustrating the methods and characteristics of various examples.

[0144] Example 1A

[0145] Photochromic wafer: A laminated photochromic wafer having a polycarbonate film used as a protective layer was cut and formed into a 4-base wafer.

[0146] Coating solution (composition A):

[0147] Component 1: 818 grams of 3-aminopropyltriethoxysilane was combined with 17 grams of deionized water and placed in a reactor flask equipped with a reflux system. The solution was mixed overnight under reflux.

[0148] Component 2: 2000 grams of 3-glycidoxypropyltrimethoxysilane was combined with 411 grams of deionized water and 8.4 grams of 10% hydrochloric acid in a reactor flask equipped with a reflux system. The solution was mixed overnight under reflux.

[0149] In a flask equipped with a thermometer and mixing apparatus, 951 grams of component 1 were mixed with 1261 grams of component 2, and the solution was heated for 30 minutes. Next, 3043 grams of isopropanol alcohol and 650 grams of ethyl alcohol were added to form a coating solution with a solid content of 23.6%.

[0150] The above coating solution was applied to a polycarbonate photochromic wafer using an immersion coating process to a dry coating thickness of 2 microns. The coating was cured in an oven at 115 degrees Celsius for 6 hours (Figure 6, Example-1 in Table 1). The surface energy of the wafer, measured by measuring the contact angle with water and iodine chloride, was 53 megajoules / square meter.

[0151] Monomer solution A: The monomer solution was mixed by adding 0.17 g of dibutyltin dichloride to a mixture of 58.8 g of 2,5 (or 2,6)-diisocyanatomethylbicyclo[2.2.1]heptane and 88.2 g of 1,6-diisocyanatohexane. Subsequently, 198 g of pentaerythritol tetrakis(3-mercaptopropionate) was added. The mixture was thoroughly mixed and then degassed under a vacuum of 5 mmbar for 1 hour. The temperature of the solution was maintained at 10°C.

[0152] Casting article: The monomer solution prepared as described above was filled into a mold containing the coated photochromic wafer described above. The monomer came into contact with the coating on both sides of the wafer. Next, the entire mold / wafer / monomer was cured in an oven and monomer polymerization was carried out by a 21-hour ramping cycle reaching a maximum temperature of 120 degrees Celsius in 4 hours. The cured optical article was removed from the mold. The appearance of the cast article was transparent, without bubbles or cloudiness.

[0153] The photochromic properties of the optical material were measured, and the initial transmittance was 95.9%, which changed to 42.9% after 15 minutes of activation.

[0154] Initial lens adhesion: A 5-kilogram iron hammer was dropped onto the optical article from a height of 40 centimeters. The optical article remained intact as a single component. No separation between the photochromic film and the resin was observed.

[0155] Environmental testing: The optical article was placed in an environmental chamber with an air temperature of 65 degrees Celsius and a relative humidity of 95% for 288 hours. A 5-kilogram iron hammer was dropped onto the optical article from a height of 40 centimeters. The optical article remained intact as a single component. No separation between the photochromic film and the resin was observed.

[0156] Examples 1B to 1D:

[0157] For Examples 1B to 1D, the photochromic wafers and coating solutions were prepared in the same manner as described in Example 1A above, except that CR-39 was used as the casting resin in Example 1B, MR-8 in Example 1C, and MR-10 in Example 1D. Table 1 shows the appearance, photochromic activity, initial lens adhesion, and environmental test results of the cast articles from Examples 1A to 1D.

[0158] Example 2:

[0159] Photochromic wafer: A laminated photochromic wafer having a polycarbonate film used as a protective layer was cut and formed into a 4-base wafer.

[0160] Coating solution (composition B):

[0161] Component 3: 150 grams of CAB-531-1 was dissolved in 850 grams of (ethyl 3-ethoxypropionate).

[0162] In a separate flask, 80 grams of dipentaerythritol tetraacrylate (PETA), 10 grams of the above component 3, 450 grams of glycol ether PM, 450 grams of n-propanol, and 10 grams of alpha-chloroacetyldiphenyl oxide (e.g., Darocure 1173) were added to form a coating solution.

[0163] The above coating solution was applied to the above photochromic wafer to a dry coating thickness of 1.1 microns using a spin coating process at a speed of 800 revolutions per minute for 1 minute. The coating was pre-dried in an oven at 50 degrees Celsius for 2 minutes, and then UV-cured with a mercury D bulb at an irradiation dose of 1000 megawatts / cm² using a Fusion UV curing system with a belt speed of 10 feet per minute.

[0164] The coating exhibited good adhesion to the wafer when tested for cross-hatch and tape tensile adhesion before and after boiling the DI for 30 minutes. The haze measurement was 0.2%. Example 2 describes a coating on a stacked photochromic wafer, not on a photochromic lens, therefore a hammer test was not performed for Example 2. The surface energy of the wafer, measured by measuring the contact angle with water and iodine chloride, was 49 megajoules / m².

[0165] Example 3:

[0166] The above coating solution from Example 2 was applied to an 8-inch x 11-inch flat photochromic laminated film using a wire rod to a dry coating thickness of 0.8 microns. The coating was pre-dried in an oven at 50 degrees Celsius for 2 minutes, and then UV-cured with an iron-type D UV bulb at an irradiation dose of 1000 megajoules / cm² using a Fusion UV curing system with a belt speed of 10 feet per minute. The coating was repeated on the opposite side of the film.

[0167] Next, the coated film was cut and formed onto an 8-base photochromic wafer (as shown in Figure 4). The coating exhibited good adhesion to the wafer when tested for cross-hatch and tape tensile adhesion before and after boiling the DI for 30 minutes. The haze measurement was 0.18%. Upon inspection, no cracks were found in the coating on either side of the wafer.

[0168] Examples 3A to 3D:

[0169] For Examples 3A to 3D, photochromic cast articles were prepared from the photochromic wafer prepared in Example 3, but different monomer solutions were used to form the casting resin in each case. In Example 3A, KT56N was used as the casting resin; in Example 3B, CR-39 was used as the casting resin; in Example 3C, MR-8 was used as the casting resin; and in Example 3D, MR-10 was used as the casting resin. Table 1 shows the appearance, photochromic activity, initial lens adhesion, and environmental test results of the cast articles from Examples 3A to 3D.

[0170] Example 4:

[0171] The coating solution from Example 2 was applied to a roll of 10 mil-thick polycarbonate film using a gravure coating process until the dried coating thickness reached 0.8 microns. The coating was pre-dried in an oven at 50 degrees Celsius for 2 minutes before exposure to an iron D-type light bulb with an irradiation dose of 1000 megajoules / cm².

[0172] The coating exhibited good adhesion to the polycarbonate film when tested for cross-hatch and tape tensile adhesion before and after boiling the DI for 30 minutes. The fogging measurement using the fogging guard was less than 0.18%.

[0173] Next, a photochromic laminate sheet was prepared using two rolls of coated polycarbonate film. The photochromic sheet was then cut and formed into an 80 mm diameter 8-base photochromic wafer. Inspection revealed no cracks in the coating on either side of the wafer.

[0174] Examples 4A to 4D:

[0175] For Examples 4A to 4D, photochromic cast articles were prepared from the photochromic wafer prepared in Example 4, but different monomer solutions were used to form the cast lenses in each case, as shown in Table 1 of Figure 6. In Example 4A, aliphatic polyurethane was used as the casting resin; in Example 4B, CR-39 was used as the casting resin; in Example 4C, MR-8 was used as the casting resin; and in Example 4D, MR-10 was used as the casting resin. The appearance, photochromic activity, initial lens adhesion, and environmental test results of the cast articles from Examples 4A to 4D are shown in Table 1 of Figure 6.

[0176] In all of the above Examples 1-4D, functional wafers were prepared using photochromic dye blends A, B, and C. Dye blend A contained 3% total dye and 1.5% stabilizer, with a dye blend fatigue of approximately 3. Dye blend B contained 4.1% total dye and 4.5% stabilizer, with a dye blend fatigue of approximately 2.5. Dye blend C contained 2.27% total dye and 1.5% stabilizer, with a dye blend fatigue of approximately 2.5.

[0177] Examples 4E to 4H:

[0178] For Examples 4E to 4H, photochromic cast articles were prepared from the photochromic wafer prepared in Example 4, but different monomer solutions were used to form the case lenses in each case, as shown in Table-1 in Figure 6. The glass mold used to prepare the cast articles was a multifocal D28 glass mold. The resulting cast articles were semi-finished D28 lenses with the design shown in Figure 8. When the lenses were taken outdoors into sunlight, all samples 4A to 4H were activated to the same gray hue and faded at a similar rate when brought indoors.

[0179] In all of the above Examples 1-4H, functional wafers were prepared using photochromic dye blends A, B, and C. Dye blend A may contain 3% total dye, 1.5% stabilizer, and about 3% dye blend fatigue. Dye blend B may contain 4.1% total dye, 4.5% stabilizer, and about 2.5% dye blend fatigue. Dye blend C may contain about 2.27% total dye, 1.5% stabilizer, and about 2.5% dye blend fatigue.

[0180] Comparative Example 5:

[0181] Photochromic wafers, monomer solutions, and cast articles were prepared in the same manner as in Example 1A, but the wafers were not coated with either coating composition A or B. The cast articles were cloudy. This experiment demonstrates that in the absence of coating composition A or B on a photochromic wafer, the protective layer of the wafer is susceptible to chemical attack by aggressive casting resin monomers, resulting in cloudy or optically opaque products.

[0182] Comparative Example 6 (using coating composition A and added surfactant):

[0183] Coating solution:

[0184] Component 1: 818 grams of 3-aminopropyltriethoxysilane C was combined with 17 grams of deionized water and placed in a reactor flask equipped with a reflux system. The solution was mixed overnight under reflux.

[0185] Component 2: 2000 grams of 3-glycidoxypropyltrimethoxysilane was combined with 411 grams of deionized water and 8.4 grams of 10% hydrochloric acid in a reactor flask equipped with a reflux system. The solution was mixed overnight under reflux.

[0186] In a flask equipped with a thermometer and mixing apparatus, 951 grams of component 1 were mixed with 1261 grams of component 2, and the solution was heated for 30 minutes. Next, 0.5 grams of Byk 333, 3043 grams of isopropanol alcohol, and 650 grams of ethyl alcohol were added to form a coating solution with a solid content of 23.6%.

[0187] The above coating solution was applied to a polycarbonate photochromic wafer (a laminated photochromic wafer with a polycarbonate film used as a protective layer was cut and formed into a 4-base wafer) using an immersion coating process until the dry coating thickness reached 2 microns. The coating was cured in an oven at 115 degrees Celsius for 6 hours. The surface energy of the wafer, measured by measuring the contact angle with water and iodine chloride, was 38 megajoules / square meter.

[0188] In Comparative Example 6, a photochromic wafer coated with the above coating solution was converted into a cast article in a mold using the same monomer solution previously described in Example 1A. The cast article was transparent and free of cloudiness, but many bubbles were formed.

[0189] Comparative Example 6 shows that the presence of the surfactant Byk 333 in the coating composition reduces the surface energy of the coating composition, and therefore bubbles are formed on the wafer surface when the wafer is cast with the resin.

[0190] Comparative Examples 7 to 9D:

[0191] In Examples 7-9D, polarizing wafers and polarizing lenses coated with coating composition A or coating composition B were prepared according to the same method as previously described in Examples 1-4D.

[0192] Examples 7 and 7A-7D are the same as Examples 1 and 1B-1D, except that the wafers used in Examples 7 and 7A-7D were dark gray D-polarized wafers instead of the photochromic wafers used in Examples 1 and 1B-1D.

[0193] Examples 8A to 8D are the same as Examples 3A to 3D, except that the wafers used in Examples 8A to 8D were brown E-polarized wafers instead of the photochromic wafers used in Examples 3A to 3D.

[0194] Examples 9A to 9D are the same as Examples 4A to 4D, except that the wafers used in Examples 9A to 9D were gray F-polarized wafers instead of the photochromic wafers used in Examples 4A to 4D.

[0195] The appearance, photochromic activity, initial lens adhesion, and environmental test results of polarizing wafers and cast articles from Examples 7-9D are shown in Table 2 of Figure 7.

[0196] Comparative Example 10.

[0197] A 60% UV-curable coating solution containing a mixture of multifunctional acrylate monomers and oligomers in 35% methyl isoamyl ketone and 5% toluene is available from PCI Labs as VG-509. The solution was diluted with a solvent mixture in a coating-to-solvent ratio of 1:4. The coating solution was applied to one side of a 12 mil thick polycarbonate roll using a gravure coating process to a dry coating thickness of 1.2 microns. The coating was pre-dried in an oven at 50 degrees before exposure to a metal halide lamp with an irradiation dose of 1400 megajoules / cm².

[0198] The coating exhibited good adhesion to the polycarbonate film when tested for cross-hatch and tape tensile adhesion before and after boiling the DI for 30 minutes. The haze measurement was 0.18%.

[0199] Next, a photochromic laminate sheet was prepared using two rolls of coated polycarbonate film with the procedure and formulation described in Laminate Example L6 of U.S. Patent No. 9,081,130, the entire sheet of which is incorporated herein by reference. The photochromic sheet was then cut and formed into 80 mm diameter single-focus 4-base and single-focus 8-base photochromic wafers. Upon inspection, no cracks were found in the coating on either side of the wafers.

[0200] As shown in Table-1 of Figure 6, photochromic cast articles were prepared from photochromic wafers prepared using a monomer mixture from allyl diglycol carbonate, available under trade name TOM 1500, to form cast lenses. The glass mold used to prepare the cast articles was a multifocal D28 glass mold. The resulting cast articles were semi-finished 4-base D28 lenses and semi-finished 8-base D28 lenses with the designs shown in Figure 8.

[0201] Next, the 8B-based semi-finished lens was processed in a typical Rx surfacing lab to obtain a finished +6.00 diopter photochromic D28 lens. Then, the 4B-based semi-finished lens was processed in a typical Rx surfacing lab to obtain a finished -4.00 diopter photochromic D28 lens. Finally, both lenses were coated with scratch-resistant and anti-reflective coatings in a typical Rx optics lab to obtain coated finished lenses.

[0202] In some cases, this application discloses the use of dual curing, such as thermocuring and photocuring. By partially curing the coating through a thermal process, sufficient adhesion to the film and thermoformability can be provided.

[0203] In some examples, this application discloses the use of photocurable coatings that are exposed to low doses of photocuring sources, including but not limited to UV, LED, or visible light, after being applied to a functional wafer or film.

[0204] In some cases, the wafer thickness can range from 0.1 millimeters to 2 millimeters.

[0205] In some cases, the coating thickness can range from 0.5 microns to 20 microns.

[0206] In some examples of this application, coated flat functional sheets or wafers are pre-formed by undergoing a thermoforming process before injection molding or casting with lens resin.

[0207] In some examples of this application, a liquid coating composition containing a solvent may be applied to a functional wafer, and the solvent may evaporate to form a coating layer on the functional wafer.

[0208] Clauses:

[0209] Examples are provided in the numbered clauses below.

[0210] Clause 1. A method for forming a cast ophthalmic lens, comprising: forming a coated functional wafer by coating a first surface and a second surface of a functional wafer with a coating composition; placing the coated functional wafer in a mold; applying a resin to the first surface and the second surface of the coated functional wafer; and curing the resin and the coated functional wafer to form a cast ophthalmic lens.

[0211] Clause 2. The method of Clause 1, wherein the functional wafer is curved.

[0212] Clause 3. The method of Clause 1, wherein the functional wafer is flat.

[0213] Clause 4. The method of Clause 3, further comprising thermoforming a coated functional wafer to impart curvature to the coated functional wafer.

[0214] Clause 5. The method of Clause 1, wherein the coating composition comprises a polymer formed from a combination of one or more hydrolyzed siloxanes having at least three functional groups, and one or more solvents.

[0215] Clause 6. The method of Clause 5, wherein the coating composition further comprises one or more of the following: an adhesion promoter, a UV absorber, a colorant, or a bluing agent.

[0216] Clause 7. The method of Clause 5, wherein the polymer is present in an amount of 20-95% relative to the solids weight of the coating composition.

[0217] Clause 8. The method of Clause 5, wherein at least three functional groups are a combination of a methacrylate and either a hydroxyl or amine functional group.

[0218] Clause 9. The method of Clause 1, wherein the coating composition comprises a crosslinked solvent-resistant polymer network formed from at least three functional groups and a flexible film-forming transparent polymer.

[0219] Clause 10. The method of Clause 9, wherein at least three functional groups are selected from the group consisting of hydroxyl, amine, imine, and methacrylate.

[0220] Clause 11. The method of Clause 9, wherein the flexible film-forming transparent polymer comprises thermoplastic polyurethane and / or cellulose acetate butyrate.

[0221] Clause 12. The method of Clause 9, wherein the coating composition further comprises one or more photochemical initiators, adhesion promoters, UV absorbers, colorants, or bluing agents.

[0222] Clause 13. The method of Clause 1, wherein the coating composition comprises an acrylate monomer, a polymer, and one or more solvents.

[0223] Clause 14. The method of Clause 1, wherein the resin comprises polycarbonate.

[0224] Clause 15. The method of Clause 1, wherein the functional wafer is selected from the group consisting of photochromic wafers, electrochromic wafers, mirror wafers, polarizing wafers, holographic optical element wafers, patterned film wafers, optical filter wafers, and colored wafers.

[0225] Clause 16. A method for forming a cast ophthalmic lens, comprising forming a coated functional wafer by coating a functional wafer with a coating composition using a gravure cylinder, placing the coated functional wafer in a mold, applying a resin to the coated functional wafer, and curing the resin and the coated functional wafer to form a cast ophthalmic lens.

[0226] Clause 17. The method of Clause 16, comprising a microgravure cylinder having 150 or 180 lines per inch.

[0227] Clause 18. The method of Clause 16, wherein the gravure cylinder includes a helical pattern.

[0228] Clause 19. The method of Clause 16, further comprising the step of trimming off excess coating to provide uniformity of coating thickness.

[0229] Clause 20. A coating composition that promotes adhesion and protection to a functional wafer, comprising a combination of two or more compounds comprising a silane having formula (I), (II) and a methacrylic acid derivative having formula (III), wherein R is a methyl group, an ethyl group, a propyltrimethoxysilyl group, or a propyltriethoxysilyl group, R1 is a hydrocarbon group having 1 to 4 carbon atoms, X is a hydrolyzable group including an alkoxy group, an acyloxy group, a halogen, or an amine, Y is a hydrogen atom or an aminoalkyl group, Z is a glycidoxy group or an epoxycyclohexyl group, comprising one or more additives and two or more solvents.

[0230] Clause 21. A coating composition according to Clause 20, wherein the coating composition comprises 20 to 95% by weight of a solid crosslinked solvent-resistant polymer network.

[0231] Clause 22. A coating composition according to Clause 20, wherein the coating composition comprises at least three active functional groups configured to promote covalent bonding of an optical article with an optical resin.

[0232] Clause 23. A coating composition according to Clause 22, wherein the active functional group configured to promote covalent bonding with the resin comprises a hydroxyl group, an amine group, an imine group, or a methacrylate group.

[0233] Clause 24. A coating composition according to Clause 23, wherein the methacrylate group is configured to promote covalent bonding with the poly(allyl dicarbonate) resin.

[0234] Clause 25. A coating composition according to Clause 23, wherein the hydroxyl group or amine group is configured to promote covalent bonding with the urethane resin.

[0235] Clause 26. A coating composition according to Clause 20, wherein one or more additives include an adhesion promoter, a UV absorber, a colorant, or a bluing agent.

[0236] Clause 27. A coating composition according to Clause 20, comprising one or more additives in an amount of 1-5% on a solid weight basis.

[0237] Clause 28. A coating composition for optical wafers comprising an acrylate derivative, a transparent polymer, and one or more additives, wherein the coating composition promotes adhesion and protection of optical articles to functional wafers.

[0238] Clause 29. A coating composition according to Clause 28, wherein the composition further comprises two or more solvents.

[0239] Clause 30. A coating composition according to Clause 28, wherein the acrylate derivative comprises 2-hydroxyethyl acrylate or an ester derivative of pentaerythritol.

[0240] Clause 31. A coating composition according to Clause 30, further comprising a pentaerythritol ester derivative, pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, pentaerythritol triacrylate, or pentaerythritol tetraacrylate.

[0241] Clause 32. A coating composition according to Clause 28, wherein the acrylate derivative comprises 20 to 95% by weight of the solid crosslinked polymer.

[0242] Clause 33. A coating composition according to Clause 28, wherein the transparent polymer comprises a thermoplastic polyurethane polymer, a thermoplastic polyester polymer, a cellulose acetate butyrate (CAB) polymer, or a vinyl chloride-vinyl acetate copolymer.

[0243] Clause 34. A coating composition according to Clause 33, comprising 1-20% of a transparent polymer on a solid weight basis.

[0244] Clause 35. A coating composition according to Clause 33, wherein the transparent polymer is configured to form a flexible film.

[0245] Clause 36. A coating composition according to Clause 33, wherein the transparent polymer contains a tensile stress of about 20 megapascals or more.

[0246] Clause 37. A coating composition according to Clause 28, wherein one or more additives include an adhesion promoter, a UV absorber, a colorant, or a bluing agent.

[0247] Clause 37. A coating composition according to Clause 28, further comprising one or more additives that initiate covalent bonding between an acrylate derivative and an optical resin.

[0248] Clause 38. A coating composition according to Clause 37, wherein the initiator further comprises a photochemical initiator, a thermal initiator, a blend of photochemical initiators, a blend of photoinitiators, or a blend of photochemical and thermal initiators.

[0249] Clause 39. A coating composition according to Clause 28, wherein the coating composition is crack-resistant under stretching.

[0250] Clause 40. A coating composition according to Clause 28, wherein the coating composition is compatible with the conditions for thermoforming a functional wafer.

[0251] Clause 41. A coating composition that promotes adhesion and protection to a functional wafer, comprising an acrylate monomer, a polymer, and one or more solvents.

[0252] Clause 42. An ophthalmic lens comprising an outer lens layer, an inner lens layer, a functional wafer embedded between the outer lens layer and the inner lens layer, a first coating layer on a first surface of the functional wafer, and a second coating layer on a second surface of the functional wafer, wherein the first coating layer and the second coating layer are configured to adhere the functional wafer to the outer lens layer and the inner lens layer, respectively.

[0253] Clause 43. A coating composition that promotes adhesion and protection to a functional wafer, comprising a polymer formed from a combination of one or more hydrolyzed siloxanes having at least three functional groups, and one or more solvents.

[0254] Clause 44. A coating composition that promotes adhesion and protection to a functional wafer, comprising an acrylate monomer, a polymer, and one or more solvents.

[0255] Clause 45. A method for forming a cast ophthalmic lens, comprising: forming a functional wafer having protective layers on both sides; forming a coating composition and applying the coating composition to the protective layers on both sides of the functional wafer to form a coated functional wafer; placing the coated functional wafer in a mold and adding a resin monomer composition to both sides of the coated functional wafer; and curing the resin monomer composition and the coated functional wafer to form a cast ophthalmic lens.

[0256] While the present invention has been described in relation to specific embodiments and uses, those skilled in the art can generate additional embodiments and modifications in light of this teaching without departing from or exceeding the spirit or scope of the claimed invention. Accordingly, it should be understood that the drawings and description herein are provided as examples to facilitate understanding of the invention and should not be construed as limiting its scope.

Claims

1. A coating composition that promotes adhesion and protection to functional wafers, A combination of multiple compounds comprising silanes having formulas (I) and (II) and methacrylic acid derivatives having formula (III), In the formula, R is a methyl group, an ethyl group, a propyltrimethoxysilyl group, or a propyltriethoxysilyl group, １ X is a hydrocarbon group having 1 to 4 carbon atoms, X is a hydrolyzable group including an alkoxy group, an acyloxy group, a halogen, or an amine, Y is a hydrogen atom or an aminoalkyl group, and Z is a glycidoxy group or an epoxycyclohexyl group. Additives and A solvent, including Coating composition.

2. A coating composition according to claim 1, comprising 20 to 95% by weight of a solid crosslinkable solvent-resistant polymer network.

3. A coating composition according to claim 1, comprising at least three active functional groups configured to promote covalent bonding between an optical article and an optical resin.

4. A coating composition according to claim 3, wherein the active functional group configured to promote covalent bonding with the resin comprises a hydroxyl group, an amine group, an imine group, or a methacrylate group.

5. A coating composition according to claim 4, wherein the methacrylate group is configured to promote covalent bonding with a poly(allyl dicarbonate) resin.

6. A coating composition according to claim 4, wherein the hydroxyl group or the amine group is configured to promote covalent bonding with the urethane resin.

7. A coating composition according to claim 1, wherein the additive comprises an adhesion promoter.

8. A coating composition according to claim 1, wherein the additive is present in an amount of 1 to 5% on a solid weight basis.

9. A coating composition for optical wafers, Acrylate derivatives and Transparent polymer and It contains additives, A coating composition characterized by promoting adhesion and protection of optical articles to functional wafers.

10. A coating composition according to claim 9, wherein the composition further comprises a plurality of solvents.

11. A coating composition according to claim 9, wherein the acrylate derivative comprises 2-hydroxyethyl acrylate or an ester derivative of pentaerythritol.

12. A coating composition according to claim 11, wherein the ester derivative of pentaerythritol further comprises pentaerythritol trimethacrylate, pentaerythritol tetramethacrylate, pentaerythritol triacrylate, or pentaerythritol tetraacrylate.

13. A coating composition according to claim 9, wherein the acrylate derivative comprises 20 to 95% by weight of the solid crosslinked polymer.

14. A coating composition according to claim 9, wherein the transparent polymer comprises a thermoplastic polyurethane polymer, a thermoplastic polyester polymer, a cellulose acetate butyrate (CAB) polymer, or a vinyl chloride-vinyl acetate copolymer.

15. A coating composition according to claim 14, comprising 1 to 20% of the transparent polymer on a solid weight basis.

16. A coating composition according to claim 14, wherein the transparent polymer is configured to form a flexible film.

17. A coating composition according to claim 14, wherein the transparent polymer contains a tensile stress of at least about 20 megapascals.

18. A coating composition according to claim 9, wherein the additive comprises a UV absorber.

19. A coating composition according to claim 9, further comprising an initiator that initiates covalent bonding between the acrylate derivative and the optical resin.

20. A coating composition according to claim 19, wherein the initiator comprises a photochemical initiator.

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