Method for making a patterned spectacle lens

Abstract

The present invention relates to a method for making a patterned spectacle lens (12, 15), comprising the following steps: a) providing a transparent polymeric film (6); b) printing a pattern on a surface of said transparent polymeric film (6) via roll-to-roll ink-jet printing, obtaining a patterned polymeric film (7, 19) having a patterned surface (7a); c) thermally forming the patterned polymeric film (7, 19) with a predetermined curvature, so as to obtain a curved wafer (10, 30, 40) having a concave patterned surface (11, 31, 41) and a convex surface; d) associating the wafer (10, 30, 40) with a polymer or glass (14, 17) from the side of the concave patterned surface (11, 31, 41).

Description

METHOD FOR MAKING A PATTERNED SPECTACLE LENS Description

[0001] Field of the invention

[0002] The present invention relates to the field of spectacle lenses. In particular, the present invention relates to a method for making a patterned spectacle lens and to a patterned spectacle lens.

[0003] Background art

[0004] Spectacle lenses are provided with a curvature which makes it difficult to print decorations on the lenses themselves. Furthermore, decorations printed on the lenses have durability issues due to their exposure to the external environment.

[0005] A known technique to add decorations on spectacle lenses, in particular sun lenses, is ink-jet printing. However, this technique does not allow to achieve good details on curved lenses and durability of decorations is in general low.

[0006] Another known technique to decorate spectacle lenses is pad printing. However, the durability of decorations is again an issue and, furthermore, design and process flexibility connected to this technique are very limited.

[0007] Therefore, the problem underlying the present invention is to overcome the drawbacks of the known techniques, in particular increase the durability of decorations on top of curved lens surfaces, while ensuring high design and process flexibility as well as good resolution of decorations themselves.

[0008] Summary of the invention

[0009] The above problem is solved by a method for making a patterned spectacle lens and by a patterned spectacle lens, as outlined in the appended claims, the definitions of which form an integral part of the present disclosure.

[0010] An object of the present invention is a method for making a patterned spectacle lens, comprising the following steps:a) providing a transparent polymeric film;b) printing a pattern on a surface of said transparent polymeric film via roll-to-roll inkjet printing, obtaining a patterned polymeric film having a patterned surface;c) thermally forming the patterned polymeric film with a predetermined curvature, so as to obtain a curved wafer having a concave patterned surface and a convex surface; d) associating the wafer with a polymer or glass from the side of the concave patterned surface.

[0011] Another object of the invention is a spectacle lens comprising a polymer or glass substrate and a curved wafer made from at least one transparent polymeric film, wherein:said wafer is provided with a concave surface having a pattern,said pattern is inkjet printed on said concave surface, andsaid concave surface is associated with said polymer or glass substrate.

[0012] The method for making a patterned spectacle lens and the patterned spectacle lens according to the present invention advantageously solve the issue of poor details and poor resolution of inkjet printed decorations on top of curved lens surfaces.

[0013] By associating the concave patterned surface of the wafer with the polymer or glass substrate of the lens, the decorations result encapsulated within the structure of the lens and, consequently, they are not exposed to the external environment. Therefore, their durability is notably increased.

[0014] In addition, the method according to the present invention advantageously revealed to be easy to implement, versatile and compatible with lenses of different materials.

[0015] Further features and advantages of the invention will become more apparent from the description of some embodiments thereof, given hereinbelow by way of nonlimiting example.

[0016] Brief description of the drawings

[0017] Figure 1 shows a scheme of the method for making a patterned spectacle lens, according to a first embodiment of the present invention.

[0018] Figure 2 shows a scheme of the method for making a patterned spectacle lens, according to a second embodiment of the present invention.

[0019] Figure 3 shows a scheme of the method for making a patterned spectacle lens, according to a third embodiment of the present invention.

[0020] Figure 4 shows a scheme of the method for making a patterned spectacle lens, according to a fourth embodiment of the present invention.

[0021] Detailed description of the invention

[0022] An object of the present invention is a method for making a patterned lens comprising: a) providing a transparent polymeric film; b) printing a pattern on a surface of the transparent polymeric film via roll-to-roll ink-jet printing; c) thermally forming the resulting film to obtain a curved wafer having a concave patterned surface; d) associating the wafer with a polymer or glass from the side of the concave patterned surface, so as to encapsulate the concave patterned surface of the wafer within the structure of the lens.

[0023] The method of the invention advantageously results in the concave patterned surface of the wafer not being exposed to the external environment.

[0024] Within the context of the present invention, the term “wafer” refers to a film structure formed of either a single film layer or a film laminate structure formed of multiple film layers attached to one another, with the aim to impart decorative properties to the finished spectacle lens when associated to the ophthalmic substrate. The wafer can be integrated into a spectacle lens thanks to different methods of manufacture, such as lamination on or within the ophthalmic substrate, association with a thermoplastic injected resin forming the ophthalmic substrate, or associationwith a casting resin forming the ophthalmic substrate.

[0025] Besides the above identified steps, the method according to the present invention advantageously comprises a step of cutting the patterned polymeric film and / or a step of cutting the curved wafer into a predetermined shape, such as circular, rectangular, strip or other shapes.

[0026] According to an embodiment, the method of the invention comprises a step of cutting the patterned polymeric film into a predetermined shape, said step being carried out between the step b) and the step c). According to this embodiment, the wafer is cut from a flat film structure ( / .e. the patterned polymeric film) that, after thermal forming with a particular curvature, results in a wafer having a desired size / curvature.

[0027] According to another embodiment, the method of the invention comprises a first step of cutting the patterned polymeric film into a predetermined shape and a subsequent step of cutting the curved wafer into a predetermined shape. According to this embodiment, the wafer is cut from a flat film structure ( / .e. the patterned polymeric film), thermally formed with a particular curvature, and recut to the desired size.

[0028] According to another embodiment, the method of the invention comprises a step of cutting the curved wafer into a predetermined shape. Said step of cutting is advantageously carried out either before the step d) or during the step d) itself.

[0029] According to an embodiment of the invention, the transparent polymeric film has a primer layer applied on it and, during the step b), the pattern is printed onto said primer layer.

[0030] The pattern printed during step b) is a decorative design with a sharp contour, i.e. a decorative design with a clearly defined profile, whose boundaries are not blurred or vague.

[0031] The pattern printed during step b) has well-defined contours which clearly delineate the patterned area of the lens from the surrounding unprinted areas. Accordingly, the pattern is characterized by crisp, precise, and unambiguous edges.

[0032] Within the context of the present invention, the term “pattern” does not include a gradient tint, the gradient tint being characterized by a gradual and continuous color transition across a surface, lacking sharp contours and discrete elements.

[0033] According to an embodiment, the pattern printed during step b) may be abstract or geometric. According to another embodiment, the pattern printed during step b) may be figurative or representational. Patterns are, for example, geometric shapes, logos and symbols, images, letters, numbers or texts.

[0034] The pattern is printed using a suitable ink. Advantageously, the roll-to-roll inkjet printing also includes a step of drying and / or curing the deposited ink.

[0035] According to an embodiment of the invention, the pattern is printed using a curing ink, preferably a UV curing ink or a thermal curing ink. Said UV curing ink may be selected, for example, from: LUS 12 inks from Mimaki; Eco-UV, EUV5-5RE, EUV5P-7RE inks from Roland; TB, LV, S1, T2 UV inks from Inkcups; Uvijet KI, KO, KN, KX inks from Fujifilm. Said thermal curing ink may be selected, for example, from: PPE, IMD inks from Triton; TA inks from Roland; Pro PIG inks from MuchColours. Accordingly, the roll-to-roll ink-jet printing includes a step of curing the ink, preferably by using UV radiation or heating.

[0036] According to an embodiment of the invention, the pattern is printed using an opaque ink. The term “opaque” denotes not optically transparent inks with haze values higher than 2. Advantageously, using opaque ink allows creating high-contrast patterns on the transparent polymeric film.

[0037] The printing process of step b), being performed via roll-to-roll ink-jet printing, is advantageously carried out on a planar surface, thus maximizing the printing qualityand resolution. Roll-to-roll ink-jet printing is a continuous, high-throughput manufacturing process where a flexible material (i.e. the transparent polymeric film) is processed as it is unrolled from a supply spool, moves through a series of processing stations, and is then collected onto a finished roll. Roll-to-roll ink-jet printing process implies that the pattern is printed multiple times on the polymeric film, which can be several meters long.

[0038] According to the embodiments shown in Figures 1 and 2, the roll-to-roll ink-jet printing of step b) is carried out by means of an apparatus 1 including a first roll 2, a second roll 3 and a printing head 4 for depositing the ink 5 on a surface of the transparent polymeric film 6 according to a predetermined pattern. The patterned film is indicated in the figures with the reference number 7 and the patterned surface thereof is indicated with the reference number 7a. The first roll 2 and the second roll 3 are reversibly configured for feed or takeup, respectively, of the transparent polymeric film 6 and the patterned film 7.

[0039] The printing head 4 is provided with one or more nozzles 8 configured to eject one or more inks 5 depending on the pattern to be printed. In the examples shown in the figures, the printing head 4 is provided with three nozzles 8 each one configured to eject an ink 5.

[0040] Advantageously, the apparatus 1 also includes a drying station (not shown) configured for drying the amount of deposited ink 5 and / or a curing station (not shown) configured for curing the amount of deposited ink 5. The drying station and / or the curing station are configured, respectively, for drying and / or curing an amount of deposited ink 5 prior to takeup of a corresponding portion of the patterned film 7 by the respective roll. According to an embodiment, a drying station may be further configured for curing the deposited ink 5. For example, the curing may be accomplished using heating or ultraviolet radiation.

[0041] According to the embodiments shown in Figures 1 and 2, the roll-to-roll ink-jet printing of step b) is carried out in the apparatus 1 and includes the following steps: 1) loading the transparent polymeric film 6 onto the first roll 2 and the second roll 3 such that the first roll 2 is configured to feed the transparent polymeric film 6 to the second roll 3 across an ink depositing area;2) depositing the ink 5 onto a portion of the transparent polymeric film 6 according to a predetermined pattern, provding a patterned film 7;3) drying and / or curing the amount of deposited ink 5;4) using the first and second rolls 2, 3 to take up the portion of the patterned film 7 upon which the ink 5 has been deposited and dried I cured, and to feed another portion of the transparent polymeric film 6 onto the ink depositing area.

[0042] According to an embodiment of the invention, the roll-to-roll ink-jet printing of step b) is carried out so as the pattern is not printed on the useful optical part of the finished spectacle lens, wherein the expression “useful optical part” denotes the region of the lens where more than 80% of the gaze directions of a user go in normal conditions of use when the lens is mounted in spectacle frames and worn by the user. According to this embodiment, preferably, the roll-to-roll ink-jet printing of step b) is carried out so as the pattern is printed on the edge of the finished patterned spectacle lens, for example along the entire perimeter of the finished lens. This may be the case of patterns printed on spectacle lenses mounted to rimless (frameless) eyeglasses, the patterns giving the illusion of a frame or rim. According to this embodiment, the pattern defines the boundary of the lens with a sharp, noticeable visual element, serving the aesthetic function of a frame (to accent the eye and the shape of the lens) without adding the structural bulk or weight of a full rim. The pattern may be a solid line, for example a thin, opaque black, gold, or silver line printed precisely along the edge; alternatively, the pattern may be a geometric motif, for example a repeatingsequence of small shapes, like diamonds or miniature circles, printed along the edge.

[0043] According to an embodiment of the invention, the transparent polymeric film 6 is selected from the group consisting of: polymethylmethacrylate, poly(ethylene terephthalate), polycarbonate, polycarbonate / polyester blends, polyamide, polyester, cyclic olefin copolymers, polyurethane, polysulfone, polyvinyl alcohol (PVA), polyethylene (PE), polypropylene (PP), cellulose acylate-based materials, and combinations thereof. An example of polyester is polyethylene terephthalate (PET).

[0044] Preferably, polycarbonate is selected from the group consisting of: polybisphenol-A carbonate, homopolycarbonate, preferably homopolycarbonate being selected from 1,1’-dihroxydiphenyl-phenylmethylmethane, 1,1’-dihroxydiphenyl-diphenylmethane, 1,1’-dihydroxy-3,3'-dimethyl diphenyl-2,2-propane, and copolymers thereof.

[0045] Preferably, polyamide is selected from amorphous polyamides such as PA 12.

[0046] Preferably, cellulose acylate-based materials include, for example, cellulose diacetate and cellulose triacetate (TAC).

[0047] According to the embodiments shown in Figures 1 and 2, the patterned film 7 resulting from the step b) is cut into a predetermined shape. In the examples shown, the patterned film 7 is cut to provide elements 9 of a substantially rectangular shape.

[0048] As already mentioned above, the patterned film 7, optionally after undergoing the cutting step, is subjected to the step c) during which it is thermally formed to reach the desired curvature, so as to obtain a curved wafer 10 having a concave patterned surface 11a and a convex surface 11b. Preferably, the step c) comprises vacuum thermoforming or male-female thermoforming, for example at a temperature ranging from 110°C to 190°C and / or for a time ranging from 2 to 10 minutes, based on the material and its thickness.

[0049] As already mentioned above, according to other embodiments (not shown), astep of cutting into a predetermined shape may be carried out on the curved wafer 10 either before or during the step d).

[0050] According to a preferred embodiment, the step d) of the method of the invention comprises associating the wafer 10 with a polymer from the side of the concave patterned surface 11a. In a first embodiment of the invention, the step d) comprises back injection of the wafer 10 with a thermoplastic resin. In a second embodiment of the invention, the step d) comprises casting the wafer 10 with a thermoset resin. Back injection and casting are known processes for making spectacle lenses having a polymeric substrate.

[0051] Back injection, also referred to as injection molding, is a process comprising: putting the wafer in a mold, more specifically on the concave side of the mold, and injecting material ( / .e. molten material for thermoplastic injection) such that the wafer is pushed in contact with the mold. According to this process, upon demolding, the wafer is on the convex side of the optical element and the material is on the back of the wafer.

[0052] According to the embodiment shown in Figure 1, the wafer 10 is back injected with a thermoplastic resin, thus obtaining a spectacle lens 12 having a thermoplastic substrate 14, wherein the concave patterned surface 11a is bonded to the thermoplastic substrate 14 and is not exposed to the external environment.

[0053] Preferably, the thermoplastic resin is selected from the group consisting of: polymethylmethacrylate, polyamide polycarbonate, polycarbonate / polyester blends, polyester, cyclic olefin copolymers, polyurethane, polysulfone, and combinations thereof.

[0054] According to an embodiment of the invention, the transparent polymeric film 6 and the thermoplastic resin used in said step d) consist of the same polymer.

[0055] In a preferred embodiment, both the transparent polymeric film 6 and thethermoplastic resin used in said step d) are polycarbonate.

[0056] In another preferred embodiment, both the transparent polymeric film 6 and the thermoplastic resin used in said step d) are polyamide.

[0057] According to an embodiment of the invention, the step d) of the method of the invention comprising back injecting the wafer 10 with a thermoplastic resin comprises the following phases:1) inserting the curved wafer 10 into a mold 13;2) injecting a molten thermoplastic resin 14, or a composition of molten thermoplastic resins, onto the concave patterned surface 11a of the wafer 10 inside the mold 13; 3) carrying out the molding;4) allowing the thermoplastic resin 14, or the composition of thermoplastic resins, to cool so as to form a thermoplastic substrate onto the wafer 10, particularly onto the concave patterned surface 11a thereof;5) ejecting the spectacle lens 12 so obtained.

[0058] In the above described phase 2), the molten resin 14 is injected at high pressure, preferably in the range of 344.73 bar to 1034.21 bar (5,000 psi to 15,000 psi), and high temperature, preferably in the range of 215.6 °C to 260 °C (420 °F to 500 °F). Depending on the transparent polymeric film 6 used to make the wafer 10, the molten resin 14 may soften the surface of the wafer 10. This softening results in an integral bonding between the wafer 10 and the resin 14 as the resin 14 solidifies.

[0059] During the above described phase 4), a packing pressure may be used for a span of time. Once the spectacle lens 12 is sufficiently rigid to resist deformation, the mold 13 is opened and the ensemble is ejected in the above described phase 5).

[0060] According to an embodiment of the invention, said step d) also comprises associating the wafer 10 with a polymer or glass from the side of the convex surface 11b, which results in the wafer 10 being embedded between two polymer or glasslayers.

[0061] According to the embodiment shown in Figure 2, the wafer 10 is casted with a thermoset resin, thus obtaining a spectacle lens 15 having a thermoset substrate 17, wherein the concave patterned surface 11a is bonded to the thermoset substrate 17 and is not exposed to the external environment. In the description below, the thermoset resin is also referred to as a casting resin.

[0062] The thermoset resin may be any transparent thermoset resin formed from any curable liquid monomer whose polymerization can be thermo or photo activated.

[0063] Preferably, the thermoset resin is selected from the group consisting of: a diethylene glycol bis(allyl carbonate), allylic and (meth)acrylic copolymers, a polythiourethane, a polyurethane, or a polyurea. In particular, a diethylene glycol bis(allyl carbonate), such as CR39®, with a refractive index of 1.5, sold by PPG Industries to make thermoset plastics, allylic and (meth)acrylic copolymers, having a refractive index between 1,54 and 1,58, a polythiourethane, such as MR series provided by Mitsui Chemicals: MR6®, MR7®, MR8®, MR10®, MR174®, a polyurethane (Trivex® / NXT ®) are suitable materials.

[0064] According to an embodiment of the invention, the transparent polymeric film 6 is a polycarbonate and the thermoset resin is a polyurethane.

[0065] Casting is a known process for making spectacle lenses having a thermoset substrate. According to this embodiment, the wafer 10 is embedded in the thickness of the casting resin. Accordinig to an embodiment, the step d) of the method of the invention comprises the following phases:1) positioning the wafer 10 into a mold assembly 16 having a first molding shell 16a and a second molding shell 16b, wherein the distance of the wafer 10 from the first and second molding shells 16a, 16b defines the depth at which the wafer 10 will be positioned into the casting resin;2) pouring a casting formulation comprising a monomer and a suitable polymerization catalyst into the mold assembly 16, letting it flowing on both sides of the wafer 10 (namely, on on the side of the concave patterned surface 11a and on the side of the convex surface 11b) and filling the space between the first molding shell 16a and the wafer 10, on the one hand, and the space between the wafer 10 and the second molding shell 16b, on the other hand;3) polymerizing the monomer so as to form a thermoset substrate 17 (more specifically, a first thermoset layer 17a and a second thermoset layer 17b) within which the wafer 10 is embedded;4) ejecting the spectacle lens 15 so obtained.

[0066] According to a particular embodiment, the step b) of the method of the invention further includes joining the patterned polymeric film 7, through its patterned surface 7a, to at least one polymeric film by a lamination process, obtaining another patterned polymeric film. The latter is a multiple patterned polymeric film, for example a double patterned polymeric film or a triple patterned polymeric film. More specifically, the expression “multiple patterned polymeric film” denotes that it is formed of multiple film layers attached to one another by means of a lamination process, for example two film layers in the case of a double patterned polymeric film and three film layers in the case of a triple patterned polymeric film.

[0067] According to this embodiment, preferably, the patterned polymeric film 7 is bonded, through its patterned surface 7a, to at least one polymeric film, by means of an adhesive, such as a liquid glue or a pressure-sensitive adhesive, having optical transparency. The adhesive is not particularly limited and may contain, for example, any of a urethane-based adhesive, an epoxy-based adhesive, an acrylic-based adhesive, a silicone-based adhesive as a main component.

[0068] According to the embodiment shown in Figure 3, the patterned film 7 isbonded, through its patterned surface 7a, to a polymeric film 18 by a lamination process, thus obtaining a double polymeric film 19 having the patterned surface 7a encapsulated therein and not exposed to the external environment.

[0069] According to an embodiment of the invention, said at least one polymeric film 18 is selected from the group consisting of: polymethylmethacrylate, polycarbonate, polycarbonate / polyester blends, polyamide, polyester, cyclic olefin copolymers, polyurethane, polysulfone, polyvinyl alcohol (PVA), polyethylene terephtalate (PET), and combinations thereof.

[0070] According to an embodiment of the invention, the transparent polymeric film 6 and said at least one polymeric film 18 consist of the same polymer.

[0071] In a preferred embodiment, both the transparent polymeric film 6 and the polymeric film 18 are polycarbonate.

[0072] In another preferred embodiment, both the transparent polymeric film 6 and the polymeric film 18 are polyamide.

[0073] According to the embodiment shown in Figure 4, the patterned film 7 is bonded, through its patterned surface 7a, to a polymeric film 18 by a lamination process, and the polymeric film 18 is, in turn, bonded to another polymeric film 20 by a lamination process, thus obtaining a triple polymeric film having the patterned surface 7a encapsulated therein and not exposed to the external environment.

[0074] According to the embodiment shown in Figure 4, the polymeric film 18 is preferably a polarized film, for example a polyvinylalcohol (PVA) or polyethylene terephtalate (PET) film. Preferably, the other polymeric film 20 consists of the same polymer as the transparent polymeric film 6, for example polycarbonate or polyamide.

[0075] According to an embodiment of the invention, the patterned film 7 is obtained from a polycarbonate (PC) film 6 and is joined, through its patterned surface 7a, to a PVA film 18 which is, in turn, joined to another polycarbonate (PC) film 20, thusobtaining a polar film structure PC-PVA-PC.

[0076] According to another embodiment of the invention, the patterned film 7 is obtained from a polyamide (PA) film 6 and is joined, through its patterned surface 7a, to a PVA film 18 which is, in turn, joined to another polyamide (PA) film 20, thus obtaining a polar film structure PA-PVA-PA.

[0077] According to the examples shown in Figures 3 and 4, the multiple patterned polymeric film is cut into a predetermined shape. In the examples shown, the multiple patterned polymeric film is cut to provide elements 29 of a substantially rectangular shape.

[0078] As described for the embodiments illustrated in Figures 1 and 2, the multiple patterned polymeric film, optionally after undergoing the cutting step, is subjected to the step c) during which it is thermally formed to reach the desired curvature, thus obtaining a curved wafer 30, 40 having a concave patterned surface 31, 41 encapsulated between respective polymeric films. Alternatively, the step of cutting into a predetermined shape may be carried out on the curved wafer 30, 40 either before or during the step d). According to this embodiment, a multiple wafer 30, 40 is obtained, which is formed of multiple film layers attached to one another by lamination. In particular, a double wafer 30 is obtained in the embodiment shown in Figure 3 and a triple wafer 40 is obtained in the embodiment shown in Figure 4.

[0079] According to the embodiments shown in Figures 3 and 4, the step d) of the method of the invention comprises back injecting the wafer 30, 40 with a thermoplastic resin. Alternatively, the step d) may comprise casting the wafer 30, 40 with a thermoset resin. The processes of back injection and casting are as described above.

[0080] According to another embodiment, not shown in the figures, the step d) of the method of the invention comprises embedding, preferably by lamination, the wafer 10 between two glass shells, which results in sandwiching the wafer between the glassshells. Advantageously, the glass shells have the same curvature as the finished spectacle lens, and the wafer has a similar curvature. According to this embodiment, during the step c), the patterned polymeric film is thermally formed such that the resulting wafer is curved to conform to the curvature of the glass shells.

[0081] Another object of the present invention is a spectacle lens comprising a polymer or glass substrate and a curved wafer made from at least one transparent polymeric film, wherein:said wafer is provided with a concave surface having a pattern,said pattern is inkjet printed on said concave surface, andsaid concave surface is associated with said polymer or glass substrate.

[0082] According to a preferred embodiment of the invention, the spectacle lens of the invention comprises a polymer substrate.

[0083] According to an embodiment of the invention, said polymer substrate consists of a thermoplastic resin or a composition of thermoplastic resins. Preferably, the thermoplastic resin is selected from the group consisting of: polymethylmethacrylate, polyamide polycarbonate, polycarbonate / polyester blends, polyester, cyclic olefin copolymers, polyurethane, polysulfone and combinations thereof.

[0084] According to an embodiment of the invention, the transparent polymeric film from which the wafer is made and the thermoplastic resin consist of the same polymer, preferably a polycarbonate or a polyamide.

[0085] According to an embodiment of the invention, said polymer substrate consists of a thermoset resin or a composition of thermoset resins. Preferably, the thermoset resin is selected from the group consisting of: a diethylene glycol bis(allyl carbonate), allylic and (meth)acrylic copolymers, a polythiourethane, a polyurethane, or a polyurea.

[0086] According to an embodiment of the invention, the transparent polymeric filmfrom which the wafer is made is a polycarbonate and the thermoset resin is a polyurethane.

[0087] According to an embodiment of the invention, the transparent polymeric film from which the wafer is made is selected from the group consisting of: polymethylmethacrylate, poly(ethylene terephthalate), polycarbonate, polycarbonate / polyester blends, polyamide, polyester, cyclic olefin copolymers, polyurethane, polysulfone, polyvinyl alcohol (PVA), polyethylene (PE), polypropylene (PP), cellulose acylate-based materials, and combinations thereof. An example of polyester is polyethylene terephthalate (PET).

[0088] Preferably, polycarbonate being selected from the group consisting of: polybisphenol-A carbonate, homopolycarbonate, preferably homopolycarbonate being selected from 1,1’-dihroxydiphenyl-phenylmethylmethane, 1,1’-dihroxydiphenyl-diphenylmethane, 1,1’-dihydroxy-3,3'-dimethyl diphenyl-2,2-propane, and copolymers thereof.

[0089] Preferably, polyamide being selected from amorphous polyamides such as PA 12.

[0090] Preferably, cellulose acylate-based materials include, for example, cellulose diacetate and cellulose triacetate (TAC).

[0091] According to an embodiment of the invention, the wafer is formed of a single film layer, namely it is obtained from a single polymeric film having a patterned surface (i.e. it is a single wafer). Examples thereof are shown in Figures 1 and 2, wherein the lens is indicated with the reference number 12, the wafer is indicated with the reference number 10 and the polymer substrate is indicated with the reference numbers 14 (Figure 1) and 17 (Figure 2).

[0092] According to another embodiment of the invention, the wafer is formed of a film laminate structure formed of multiple film layers attached to one another by alamination process. In particular, the wafer is obtained from a multiple polymeric film having a patterned surface encapsulated between two film layers (i.e. it is a multiple wafer).

[0093] According to an embodiment, the wafer is obtained from a double polymeric film having a patterned surface encapsulated between two film layers. Said double polymeric film is obtained by a lamination process as described above, namely by joining a patterned polymeric film, through its patterned surface, to another polymeric film. According to an embodiment of the invention, said two films consist of the same polymer, preferably polycarbonate or a polyamide. An example thereof is shown in Figure 3.

[0094] According to an embodiment, the wafer is obtained from a triple polymeric film having a patterned surface encapsulated between two film layers, namely by joining a first patterned polymeric film, through its patterned surface, to a second polymeric film which is, in turn, joined to a third polymeric film. According to an embodiment of the invention, the first and second films consist of the same polymer, preferably polycarbonate ora polyamide; preferably, the second film is a polarized film consisting of polyvinylalcohol (PVA) or polyethylene terephtalate (PET). An example thereof is shown in Figure 4.

[0095] According to a particular embodiment, the wafer includes a patterned polycarbonate (PC) film which is joined, through its patterned surface, to a polarized film consisting of polyvinylalcohol (PVA) or polyethylene terephtalate (PET), which is in turn joined to another polycarbonate (PC) film.

[0096] According to another embodiment, the wafer includes a patterned polyamide (PA) film which is joined, through its patterned surface, to a polarized film consisting of polyvinylalcohol (PVA) or polyethylene terephtalate (PET), which is in turn joined to another polyamide (PA) film.

[0097] According to another embodiment, not shown in the figures, the spectacle lens of the invention comprises a glass substrate and the curved wafer is embedded, preferably laminated, between two glass shells.

[0098] According to an embodiment of the invention, the pattern is not printed on the useful optical part of the finished spectacle lens, wherein the expression “useful optical part” is as defined above. According to this embodiment, preferably, the pattern is printed on a part of the wafer intended to correspond to the edge of the spectacle lens, for example along the part of the wafer which would correspond to the entire perimeter of the lens; this may be the case of patterns printed on spectacles lens mounted to rimless (frameless) eyeglasses to give the illusion of a frame or rim. Spectacle lenses applied to rimless (frameless) eyeglasses are not housed in a traditional full or half-rim frame, but they are typically mounted directly to the bridge and temples using special screws or anchors. According to this embodiment, the pattern defines the boundary of the lens with a sharp, noticeable visual element, serving the aesthetic function of a frame (to accent the eye and the shape of the lens) without adding the structural bulk or weight of a full rim. The pattern may be a solid line, for example a thin, opaque black, gold, or silver line printed precisely along the edge; alternatively, the pattern may be a geometric motif, for example a repeating sequence of small shapes, like diamonds or miniature circles, printed along the edge.

[0099] All the features disclosed with reference to the method of the invention also apply to the spectacle lens of the invention.

[0100] It is apparent that those which have been described are only particular embodiments of the present invention. Those skilled in the art will be able to make all the necessary modifications to the method and the spectacle lens of the present invention for the adaptation thereof to particular conditions, without however departing from the scope of protection as defined in the appended claims.

Claims

CLAIMS1. A method for making a patterned spectacle lens (12, 15), comprising the following steps:a) providing a transparent polymeric film (6);b) printing a pattern on a surface of said transparent polymeric film (6) via roll-to-roll ink-jet printing, obtaining a patterned polymeric film (7, 19) having a patterned surface (7a);c) thermally forming the patterned polymeric film (7, 19) with a predetermined curvature, so as to obtain a curved wafer (10, 30, 40) having a concave patterned surface (11a, 31, 41) and a convex surface (11b);d) associating the wafer (10, 30, 40) with a polymer or glass (14, 17) from the side of the concave patterned surface (11a, 31, 41).

2. A method according to claim 1 , comprising a step of cutting the patterned polymeric film (7, 19) and / or a step of cutting the curved wafer (10, 30, 40) into a predetermined shape.

3. A method according to claim 1 or 2, wherein the pattern is printed using a curing ink (5), preferably an opaque ink, and said step b) comprises curing the ink (5).

4. The method according to any one of the previous claims, wherein said step b) comprises printing a pattern so as the pattern is not printed on the useful optical part of the patterned spectacle lens (12, 15), preferably the pattern is printed on the edge of the patterned spectacle lens (12, 15).

5. The method according to any one of the previous claims, wherein the transparent polymeric film (6) is selected from the group consisting of: polymethylmethacrylate, poly(ethylene terephthalate), polycarbonate, polycarbonate / polyester blends, polyamide, polyester, cyclic olefin copolymers, polyurethane, polysulfone, polyvinyl alcohol (PVA), polyethylene (PE), polypropylene (PP), cellulose acylate-based materials, and combinations thereof,preferably, polycarbonate being selected from the group consisting of: polybisphenol-A carbonate, homopolycarbonate, preferably homopolycarbonate being selected from 1,1’-dihroxydiphenyl-phenylmethylmethane, 1,1’-dihroxydiphenyl-diphenylmethane, 1,T-dihydroxy-3,3'-dimethyl diphenyl-2,2-propane, and copolymers thereof, preferably, polyamide being selected from amorphous polyamides such as PA 12, preferably, cellulose acylate-based materials including cellulose diacetate and cellulose triacetate (TAC).

6. The method according to any one of the previous claims, wherein said step d) comprises back injecting the curved wafer (10, 30, 40) with a thermoplastic resin, preferably said thermoplastic resin being selected from the group consisting of: polymethylmethacrylate, polyamide polycarbonate, polycarbonate / polyester blends, polyester, cyclic olefin copolymers, polyurethane, polysulfone, and combinations thereof.

7. The method according to claim 6, wherein the transparent polymeric film (6) and the thermoplastic resin consist of the same polymer, preferably a polycarbonate or a polyamide.

8. The method according to any one of claims 1 to 5, wherein said step d) also comprises associating the wafer (10, 30, 40) with a polymer or glass (17) from the side of the convex surface (11b).

9. The method according to claim 8, wherein said step d) comprises casting the wafer (10, 30, 40) with a thermoset resin, preferably said thermoset resin being selected from the group consisting of: a diethylene glycol bis(allyl carbonate), allylic and (meth)acrylic copolymers, a polythiourethane, a polyurethane, ora polyurea.

10. The method according to claim 9, wherein the transparent polymeric film (6) is a polycarbonate and the thermoset resin is a polyurethane.

11. The method according to any one of the previous claims, wherein the step b) further includes joining the patterned polymeric film (7), through its patterned surface (7a), to at least one polymeric film (18, 20) by a lamination process, obtaining a multiple patterned polymeric film (19).

12. The method according to claim 11, wherein said at least one polymeric film (18, 20) used for lamination is selected from the group consisting of: polymethylmethacrylate, polycarbonate, polycarbonate / polyester blends, polyamide, polyester, cyclic olefin copolymers, polyurethane, polysulfone, polyvinyl alcohol (PVA), polyethylene terephtalate (PET), and combinations thereof.

13. The method according to claim 11 or 12, wherein said transparent polymeric film (6) and said at least one polymeric film (18, 20) consist of the same polymer, preferably a polycarbonate or a polyamide.

14. The method according to any one of claims 11 to 13, wherein the step b) includes: joining the patterned polymeric film (7), through its patterned surface (7a), to a polarized polymeric film (20) consisting of polyvinylalcohol (PVA) or polyethylene terephtalate (PET), andjoining said polarized film to another polymeric film (18) which preferably consist of the same polymer as the transparent polymeric film (6), preferably polycarbonate or polyamide.

15. Spectacle lens (12, 15) comprising a polymer or glass substrate (14, 17) and a curved wafer (10, 30, 40) made from at least one transparent polymeric film, wherein: said wafer (10, 30, 40) is provided with a concave surface (11a, 31, 41) having a pattern,said pattern is inkjet printed on said concave surface (11a, 31, 41), andsaid concave surface (11a, 31, 41) is associated with said polymer or glass substrate (14, 17).

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