CN1214007A - Optical Lens Preforms - Google Patents

Abstract

The invention relates to an optical preform (10) consisting of an optical article, such as a single-vision lens, and an adjacent partially cured resin layer (20). The adjacent layer (20) may be fitted to a mold (30) and further hardened to improve the optical properties of the preform (10) as described above. Further, the partially cured resin layer (20) may be placed on the optical article (10) before the optical article is placed in and against the mold (30), or the partially cured resin layer (20) may be placed on the surface of the mold (30) in advance before the optical article (10) is placed in and against the mold (30).

Description

Optical Lens Preforms

Technical Field of the Invention

The present invention relates to optical preforms, more particularly optical preforms having an adjacent layer of partially cured resin, which are used to make optical products.

Technical Background of the Invention

Optical components are usually produced by direct molding of polymerizable resins or by grinding blanks of semi-finished products previously made of polymerizable resins into required products, e.g. ophthalmic Lenses used etc. Optical elements can also be prepared as multilayer assemblies by plasma polymerization, centrifugal spin casting, sequential casting or photolithography. In any case, the prepared optical components must meet certain optical technical requirements.

In many applications, such as ophthalmic lens applications, the number of types of optical properties that need to be changed is so great that it may not be economically feasible to prefabricate all optical elements that may be required. Therefore, in the manufacture of multifocal ophthalmic lenses, two steps are usually taken: 1) molding the semi-finished blank, and 2) grinding the above-mentioned unfinished surface to form the final intended product.

The process of making ophthalmic lenses is very time consuming and expensive. As a result, many process technologies for making lenses have emerged. For example, Blum (US Pat. No. 5,219,497) proposes casting a thin layer of polymerizable resin on the outer surface of a single image (vision) lens or semi-finished blank that provides additional magnification on the lens. Typically, a distance specification including any required toric correction is included in the single image lens, and the resin layer molded on the single image (vision) lens retains the distance correction in the lens region provided by the lens blank. Greshes (US Patent, US 4,190,621) describes a molding method that involves holding a lens blank in a jig and placing a mold of matching curvature (degrees) under the lens, with the mold between the mold and the lens preform intervene in layers of liquid resin. Verhoeven (US Pat. No. 4,623,496) discloses a method in which a thin layer of resin is molded onto an optical preform having a spherical geometry. Ito (US Pat. No. 4,536,267) describes a photo-synthesizable resin in combination with a photoinitiator and a thermoplastic initiator. Toh (US 4,912,185) describes a photopolymerizable resin for the preparation of various lenses.

In various cases where the lens is molded with liquid resin, some inconveniences are caused. For example, transport and dispatch of reactive liquids. In addition, the shrinkage that develops during the hard curing process can optically deform (distort) the lens.

Summary of the invention

The present invention can solve the above-mentioned inconveniences existing in the prior art by providing an optical preform composed of an optical article, such as a single-image (optical) lens. The latter has an adjacent layer of partially hardened resin. The adjacent layer can be molded and further hard cured (eg, crosslinked) to modify the optical properties of the preform as desired. The above-mentioned adjacent layers can be placed on the surface of the optical article (either previously or subsequently).

Alternatively, the aforementioned partially hardened resin layer may be placed on the optical article prior to placing the optical article against the mould. Alternatively, the partially hardened resin layer described above may be placed on the surface of the mold prior to placing the optical article against the mold. In any event, the above-mentioned mold surface on which the layer of partially hardened resin may be placed is generally substantially convex or concave.

The above preforms can be prepared in large quantities and stored at the distribution point, which can be easily converted into many optical products, such as polished spherical or aspheric, toric, single image (visual), bifocal , multifocal or progressive blanks, ophthalmic lenses or lens preforms. Other optical articles may also include molds, intraocular lenses, contact lenses or other optical elements, such as those used in optical signal processing or optical computing.

Although a mold can be used to determine the final surface shape structure of the above partially hardened resin layer. However, the shape structure can also be achieved by various known processing methods which do not require the use of moulds. For example, spin (centrifugal) method, spray method, dipping method and photoplate method. As an example, a partially hardened polymer layer can be formed using a spin process. The partially hardened polymer layer can be heated by any heating method so that during spinning, the polymer layer softens and is able to flow to form the desired shape. When the partially hardened polymer layer achieves the desired fluidity and viscosity retention, the photocuring process can begin. As the partially hardened polymer layer continues to rotate, the light curing process continues. Light curing as described above further hardens the polymer layer into its final shape. Depending on the initiators and chemical composition used, the process can be carried out in an oxygen-free environment or in an oxygen-free environment, for example in the presence of nitrogen. Light curing can be performed with visible or ultraviolet light, or both.

A brief description of the drawings

Fig. 1 is a sectional view of a mold and an optical preform according to the present invention;

Figure 2 is a cross-sectional view of an optical article and adjacent mold according to the present invention;

Figure 3 is a cross-sectional view of a partially hardened layer on an optical article according to the present invention;

Figure 4 is a cross-sectional view of a partially hardened layer placed on a concave surface of a mold according to the present invention;

Figure 5 is a cross-sectional view of a partially hardened layer placed on the convex surface of a mold in accordance with the present invention.

Detailed description

Fig. 1 shows an embodiment of preparing an optical preform without using a liquid polymerizable resin according to the present invention. wherein an optical preform comprising an optical article (10), such as a single-image (vision) lens, is tightly bonded on one surface of the lens to an adjacent partially hardened polymer layer (20), in addition to coated on the polymer layer (20) with additional adjacent layers for providing special optical properties and/or anti-scratch properties, although said polymer layer may be pre-placed on the surface of said optical article, However, it is also possible to place the polymer layer beforehand on the mold surface.

In the embodiment shown in Figure 1, the optical preform with attached polymer layers is placed in, and brought into contact with, a mold (30) having the desired optical geometry of the final lens. Wherein, the action of light, heat or light and heat can be implemented on it, so that the curing action of the adjacent layer (20) can be finally completed, and the lens as a finished product can be formed. The above-mentioned layer (20) is compatible with the mold (30). For example by heat, pressure or heat and pressure. In this way, a single image (vision) lens can be converted into a bifocal lens according to the specific requirements of the user.

When the partially hardened polymer layer is placed on the mold surface in advance, the mold/polymer layer combination is then placed on and in contact with the surface of the optical article, the polymer layer is then fully cured, and the mold is removed Before, the cured polymer layer is bonded to the surface of the optical article.

Finished lenses with complex geometries can be produced in large quantities at low cost by using optical preforms with optical articles (10) and polymer layers (20) having certain elements of the finished optical geometry. Among other things, the mold (30) or other shaping method, can provide the rest of the geometrical elements of the finished product from the above-mentioned polymer layer (20). For example, an aspherical lens for correcting spherical aberrations can be prepared by using an optical preform comprising a spherical optical article (10) and an adjacent layer (20), and an aspheric mold matching the bottom surface. Thus, the aforementioned optical article (10) may be a spherical, aspherical or toric single image lens, bifocal, multifocal or progressive lens, etc. Likewise, the mold (30) can also be used to provide spherical, aspheric or toric corrected, bifocal, multifocal, or progressive regions, among others. The only limitation to this approach involving complex optical geometries is that the required optical geometry can be decomposed into one or more simpler geometric elements before using the linear superposition method.

Monoscopic (optical) or other lenses made of glass, plastic, polycarbonate such as CR-39 ^TM , bisphenol A, or other polymers can be used as optical articles in the preparation of optical preforms . Such optical articles may be hard, soft or flexible. The refractive index of this lens can be selected from a wide range of, for example, 1.42-1.70 as a typical ophthalmic lens. Semi-finished blanks can also be used as optical articles in optical preforms. Other items, such as refractive lenses, optical reflectors, prisms, etc., can also be processed and modified in this way to form finished optical products. Thus, optical articles can be made of plastic, metal or glass, or combinations thereof.

The adjacent polymer layers may be formed by polymerizing acrylate, methacrylate, styrene or allyl monomer mixtures. The curing described above can be accomplished thermally, photochemically or both. The monomers of the components used are preferably selected according to the chemical composition of the convex surface of the single image (vision) lens and its refractive index. The formulation of the adjacent layers described above is preferably such that upon completion of curing the adjacent layers form a strong and sustained bond to the optical article. The above-mentioned adjacent layer is also preferably formulated to form a refractive index within 0.05 units, or more preferably within 0.03 units, of that of the above-mentioned single image (visual) optical article after it is fully cured. The above-mentioned polymerization can be carried out using a thermal polymerization initiator, a photopolymerization initiator or a mixture thereof.

According to a preferred embodiment of the present invention, the polymerization is carried out until the glass transition temperature reaches the range of 20°-40°C, more preferably 25-35°C. The crosslink density in this state is preferably less than 10 ^-4 mol/liter. The polymer layer is then preferably impregnated with the multifunctional monomer and additional polymerization initiator. When the optical preform is placed on and contacts the mold surface, the above-mentioned initiator can play the role of continuing curing, and the multifunctional monomer can promote the crosslinking density between layers. In addition, the adjacent layer can also be formulated with a mixture of thermal and photoinitiators such that only heat is used to form the adjacent layer. Instead, save the photoinitiator added to the formulation for the final molding step. In addition, photoinitiators that can cure at different wavelengths can also be considered.

The aforementioned adjacent layers may be formed on one or more surfaces of an optical article to produce an optical preform by immersing the surface of the optical article in a monomer formulation bath and applying the liquid formulation by spin coating. A uniform layer is formed on the surface of the above-mentioned optical article, whereby the liquid formulation layer is applied to the optical article. Additionally, as shown in Figure 2, the optical article (10) may be placed in an adjacent layer mold (40). The recess (50) formed between the optical article (10) and the adjacent layer mold (40) is filled with monomer formulation. The layer formed by the liquid formulation described above may then be partially cured, as previously described. The curing described above can be carried out thermally, photochemically or both. The above-mentioned coating and curing process of the liquid layer can be repeated. The same formulation can be used to form a certain thickness, and different formulations can be used to change its characteristics. The optical preform formed above can be cleaned and checked for uniformity of cure level and proper thickness of adjacent layers. For this purpose, standard chemical and analytical techniques may be employed.

Although Figure 1 shows an embodiment in which the partially hardened resin layer is placed on the convex surface of the optical article prior to placing the resin layer/optical article assembly on the mold surface, in practice the resin layer (20) It can also be placed on the concave surface of the optical article (10), as shown in FIG. 3 . In other embodiments shown in FIGS. 4 and 5, before the optical article (10) is placed on the mold/resin layer assembly, the partially cured resin layer (10) can be placed on the mold (30 respectively) at first. ) on a convex or concave surface.

The molds used to fully hard-cure the optical preforms can be made of plastic, glass, metal-coated glass, metal itself, etc., and can be reusable or disposable. Although not always required, the bottom curve of the mold should preferably match the end curves of the optical preform and allow for shrinkage of adjacent layers during the hard curing process. Advantageously, most of the shrinkage phenomena that accompany polymerization occur during the formation of adjacent layers. For example, typical mixtures of monofunctional and bifunctional acrylates exhibit polymerization shrinkage of 12-18% during full hard cure. However, up to 70% of the overall shrinkage occurs in the initial polymerization reaction leading to the formation of the adjacent layer 20 . The rest of the shrinkage is related to the crosslinking reaction, which takes place in the mold (30).

If the mold 30 is made of glass or other material transparent to the actinic radiation used to initiate the optical crosslinking, the radiation can penetrate the mold (30). If the mold is made of metal or some other substance opaque to actinic rays, the rays penetrate the optical article (10). In some cases, the following actinic rays can penetrate the above-mentioned mold 30 and optical article 10 .

We describe the invention by the following examples of the invention, which are provided for illustration only and are not intended to limit the invention.

Example 1

An optical preform is provided comprising ^a single image (vision) lens molded from a CR-39 ^TM monolith, and an adjacent Optical articles composed of partially hardened polymer layers. The polymer layer contains unreacted cross-linking agent and additional unreacted photoinitiator to form complete hardening. The above-mentioned polymer layer is sufficiently hardened to render the substance elastic and has a glass transition temperature in the range of 25-35°C. The above optical preform was then placed in a bifocal mold (FT-28) with matching base curves and desired addition curves. It is then rotated to obtain the predetermined angular orientation formed between the axis of the additive magnification module and the axis of the toric surface of the CR-39 single image (vision) lens. Then, the above-mentioned mold assembly is placed in a hard curing chamber equipped with ultraviolet lamps and programmable heaters. The mold assembly is heated to a predetermined temperature at which the adjacent layers begin to fluidize and assume the shape of the mold. The coating material flows into the addition magnification area of the mold and reduces the thickness of the resin layer associated with the distance magnification area. This is followed by a full hard cure using UV radiation and heat. As the above-mentioned adjacent layers become cross-linked, the glass transition temperature rises to 80-90°C. In most ophthalmic applications, the surface needs to have certain hardness and scratch resistance.

Example 2

An optical preform is provided which comprises an optical article consisting of an aspherical single image (vision) lens made from bisphenol A polycarbonate to which is attached a first adjacent layer. The latter is then coated with a second adjacent layer of a different composition. The first adjacent layer is composed of a partially polymerized copolymer of monofunctional and bifunctional acrylates and methacrylates, which also contains unreacted multifunctional acrylates and excess unreacted photoinitiated agent. The aforementioned second adjacent layer is also a partially polymerized, non-crosslinked copolymer of acrylates and methacrylates, but contains highly functionalized acrylate or styrene crosslinkers for scratch resistance, and Unreacted excess photoinitiator. The optical preforms described above are packaged. Wrap it in release paper to protect the integrity of adjacent layers and keep the surface dust-free. The above-mentioned optical preform is placed in a glass mold which matches the base curve of the preform and has the added curvature required by the progressive addition multifocal lens design. The above-mentioned preform can be used as a toroidal lens blank. Or it can be edged to the frame before the final molding operation. Align the toric axis of the preform with an invisible mark on the mold so that the toric axis can be aligned as ordered. Then, the mold assembly is placed into a hard curing chamber. According to a first embodiment, hard curing of the adjacent layer is accomplished, the hard curing process, using a second adjacent coating layer, forming an outwardly hardened surface on the convex surface of the finished progressive addition lens. Anti-scratch layer. The inner adjacent coating flows into the concave body between the single image (vision) lens and the glass mold, thus facilitating the formation of the progressive addition geometry.

Example 3

This example describes the preparation of an optical preform with adjacent layers placed on the concave surface of a single image (vision) lens. The single image (vision) lenses were molded from the diacrylate of bisphenol A, a formulation of styrene and divinylbenzene. Its refractive index is 1.60. Liquid resin formulations consisting of mixtures of blocked bisphenol A, monoacrylates, monoallyl chain terminated bisphenol A diesters, monofunctional aliphatic acrylates and photopolymerization initiators such as Irgacure 184 of. A quantity of the above liquid resin formulation is added to the concave surface of the above single image (vision) lens and a flexible spacer is placed on the edge of the above single image (vision) lens. And place the glass mold that can pass through the ultraviolet rays of 320-390mm wavelength on the top of the liquid resin formulation so that it can be diffused to form a predetermined thickness layer. The mold assembly described above was subjected to a hard cure cycle consisting of UV radiation and heated slides. After hard curing, the optical preform is removed from the mold and cleaned and packaged before shipping.

Example 4

This practice involves the application of a partially hard-cured polymerizable resin layer on the concave surface of a single-use mold. A viscous liquid layer of polymerizable resin is applied to a plastic disposable mold made of styrene copolymer. It is then exposed to UV light from a lamp. The hard-cured coating layer becomes a polymer layer having a crosslink density of less than 1 x 10 ^-4 mol/liter. Then, the coating is impregnated with additional multifunctional monomers and photoinitiators. The thickness of the coating is 50-150 microns. The above-mentioned one-time mold can be a spherical or aspherical geometric surface, and can also be a monofocal or multifocal optical geometric surface. In order to form a suitable material layer, the capacity of the resin added to the mold depends on the size of the addition magnification (add power) ratio of the bifocal type of addition. Wrap the pre-coated mold with release paper. It is then shipped to a retail store or fabrication plant. To make a lens, an optical preform having a magnification corresponding to the telemagnification of the finished lens may be selected. It was then placed on the pre-coated mold with the toric axis pointing at an angle relative to the axis of the mold's additive magnification required in this specification. The mold assembly is placed in a hard curing chamber and first subjected to a heating cycle to soften or liquefy the conformal layer and bring it into intimate contact with the surface of the optical preform. When the hard curing process is complete, a finished bifocal or multifocal lens can be obtained.

Claims (60)

1. A method for preparing optical finished products, comprising the following steps: a) is an article for optics; b) bonding at least one partially hardened polymer layer to at least one surface of the optical article. 2. The method of claim 1, further comprising the step of forming at least one partially hardened polymer layer into a desired surface topography. 3. A method according to claim 2, wherein in said forming step, the partially hardened polymer layer is heated above its glass transition temperature. 4. The method of claim 2, wherein the forming step further comprises the step of c) providing a mold with a forming surface; d) bringing the molding surface of said mold into releasable contact with the outermost surface of at least one partially hardened polymer layer; e) removing the mold from said at least one partially hardened polymer layer. 5. A method according to claim 4, wherein step b is carried out before step d. 6. A method according to claim 4, wherein step d is carried out before step b. 7. The method of claim 4, further comprising hard curing said at least one partially hardened polymer layer to form a substantially hardened layer. 8. A method for preparing an optical preform, comprising the following steps: a) provide an optical item; b) implementing at least one partially hardened polymer layer on at least one surface of the optical article, the latter having an innermost surface and an outermost surface; c) bonding the innermost surface of the partially hardened polymer layer to at least one surface of the aforementioned optical article to form an optical preform. 9. The method of claim 8, wherein said at least one partially hardened polymer layer has a glass transition temperature of about 20-40°C. 10. The method of claim 9, wherein said at least one partially hardened polymer layer has a glass transition temperature of about 25-35°C. 11. The method of claim 8, wherein the at least one partially hardened polymer layer has a crosslink density of less than about ^10-4 moles/liter. 12. The method of claim 8, further comprising the step of saturating the partially hardened polymer layer with a multifunctional monomer and at least one polymerization initiator. 13. A method according to claim 8, wherein at least one partially hardening polymer is applied by providing a layer of liquid monomer mixture on at least one surface of said optical article, and partially hardening said layer of liquid monomer mixture. object layer. 14. The method of claim 16, wherein the liquid monomer mixture is a monomer mixture selected from the group consisting of acrylate monomers, methacrylate monomers, styrene monomers and allyl monomers. 15. The method of claim 14, wherein at least one polymerization initiator is added to said liquid monomer mixture, said at least one polymerization initiator being a thermal initiator, a photoinitiator or both. 16. The method of claim 15, further comprising the step of impregnating said partially hardened polymer layer with a multifunctional monomer and an additional amount of a polymerization initiator. 17. The method of claim 16, wherein the glass transition temperature of the at least one partially hardened polymer layer is about 25-35°C. 18. The method of claim 17, wherein the at least one partially hardened polymer layer has a crosslink density of less than about ^10-4 moles/liter. 19. A method according to claim 16, wherein at least one polymerization initiator is added to the liquid monomer mixture. 20. The method of claim 19, wherein at least one polymerization initiator is a thermal initiator, a photoinitiator or both. 21. The method of claim 16, wherein the layer of liquid monomer mixture is provided by immersing the optical article in a bath of liquid monomer. 22. The method according to claim 16, wherein the liquid monomer mixture layer is uniformly applied on the surface of the optical article by a spin centrifugation method to form the liquid monomer mixture layer. 23. The method according to claim 16, wherein by arranging the optical article, the liquid monomer mixture and the adjacent mold layers such that a recess is formed between the molds of the optical article and the adjacent layers to be filled with said liquid monomer mixture to form The liquid monomer mixture layer described above. 24. The method of claim 8, further comprising the step of: d) providing a mold with a molding surface having the desired optical geometry; e) bringing the outermost surface of the at least one partially hardened polymer layer into releasable contact with the molding surface of the mould. 25. A method according to claim 24, wherein step b is carried out before step e. 26. A method according to claim 24, wherein step e is carried out before step b. 27. A method for preparing spherical, aspheric or toric lens products with single image (vision), bifocal, multifocal or progressive areas, comprising the following steps: a) provide an optical item; b) providing a mold with a molding surface having the desired optical geometry; c) applying at least one partially hardened polymer layer to at least one surface of the optical article, the partially hardened polymer layer having an innermost surface and an outermost surface, wherein the innermost surface of the partially hardened polymer layer surface contact on at least one surface of the optical article; d) bonding the partially hardened polymer layer to at least one surface of the optical article to form an optical preform; e) releasably contacting an outermost surface of said at least one partially hardened polymer layer to a molding surface of said mould; f) making said at least one partially hardened polymer layer suitable for said mould; g) further hardening of said partially hardened polymer layer by exposing said optical preform to light or heat or a combination of light and heat to form a finished lens; h) Remove the above finished lens from the mold. 28. A method according to claim 27, wherein said partially hardened polymer layer is fitted into said mold by heating said partially hardened polymer layer above its glass transition temperature. 29. The method of claim 28, wherein the glass transition temperature of at least one partially hardened polymer layer is about 20-40°C. 30. The method of claim 29, wherein the glass transition temperature of at least one partially hardened polymer layer is about 25-35°C. 31. The method of claim 28, wherein at least one of the partially hardened polymer layers has a crosslink density of less than about ^10-4 moles/liter. 32. A method according to claim 27, wherein at least one partially hardened polymer layer additionally has a refractive index within 0.05 units of the refractive index of the optical article. 33. The method of claim 27, wherein at least one partially hardened polymer layer additionally has a refractive index within 0.03 units of the refractive index of the optical article. 34. The method of claim 27, wherein prior to contacting said mold, at least one partially hardened polymer layer is impregnated with a multifunctional monomer and an additional amount of a polymerization initiator. 35. The method of claim 27, wherein step (c) is performed before step (e). 36. The method of claim 27, wherein step (e) is performed before step (c). 37. A method according to claim 23, wherein at least one partially cured polymer layer is applied by providing a layer of a liquid monomer mixture on at least one surface of said optical article, and using the latter to partially harden, the liquid monomer The monomer mixture is a mixture of monomers selected from the group consisting of acrylate monomers, methacrylate monomers, styrene monomers and allyl monomers. 38. The method of claim 37, wherein at least one polymerization initiator is added to said liquid monomer mixture, said at least one polymerization initiator being a thermal initiator, a photoinitiator or both. 39. The method of claim 38, further comprising the step of impregnating said partially hardened polymer layer with a multifunctional monomer and an additional amount of a polymerization initiator. 40. The method of claim 39, wherein at least one of the partially hardened polymer layers has a crosslink density of less than about ^10-4 moles/liter. 41. Mold assemblies for the preparation of finished optical products, comprising: a mold having a forming surface, and At least one partially hardened polymer layer is releasably attached to the molding surface of the mold. 42. An optical preform comprising: An optical article and at least one partially hardened polymer layer bonded to at least one surface of the optical article. 43. An optical preform according to claim 42, wherein the glass transition temperature of at least one partially hardened polymer layer is about 20-40°C. 44. An optical preform according to claim 43, wherein the glass transition temperature of at least one partially hardened polymer layer is about 25-35°C. 45. An optical preform according to claim 42, wherein at least one of the partially hardened polymer layers has a crosslink density of less than about ^10-4 moles/liter. 46. An optical preform according to claim 42, wherein at least one partially hardened polymer layer is selected from the group consisting of acrylate monomers, methacrylate monomers, styrene monomers and allyl monomers. Made from a mixture of monomers. 47. The optical preform according to claim 46, wherein said monomer mixture further contains at least one polymerization initiator. 48. An optical preform according to claim 47, wherein at least one polymerization initiator is a thermal initiator, a photoinitiator or both. 49. Optical preform according to claim 42, wherein said optical article is a single image (vision) lens having a spherical geometry. 50. An optical preform according to claim 42, wherein said optical article is a single image (optical) lens of aspherical geometry. 51. The optical preform according to claim 42, wherein the optical article is made of glass. 52. The optical preform according to claim 42, wherein the optical article is made of an organic polymer. 53. An optical preform according to claim 42, wherein at least one partially hardened layer is placed on the convex surface of the optical article. 54. The optical preform of claim 42, wherein at least one partially hardened layer is disposed on the concave surface of the optical article. 55. The optical preform of claim 54, wherein the convex surface of the optical article includes a region of additive magnification. 56. The optical preform of claim 54, wherein the convex surface of the optical article has an aspherical geometry. 57. An optical preform according to claim 42, wherein the refractive index of at least one partially hardened layer when fully hardened is 0.05 units of said optical article. 58. An optical preform according to claim 42, wherein the refractive index of at least one partially hardened layer when fully hardened is 0.03 units of said optical article. 59. The optical preform of claim 42, wherein at least one of the partially hardened layers includes unreacted polymerization initiator and multifunctional monomer. 60. An optical article comprising: An optical article and at least one partially hardened polymer layer bonded to at least one surface of the optical article.

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