Method for preparing a functional laminate

Abstract

The present disclosure relates to a method for preparing a laminate or laminated lens, comprising obtaining a first plastic substrate having a front surface and a back surface, treating the front surface of the first plastic substrate or the back surface of the first plastic substrate, and laminating a second plastic substrate onto the treated front surface or the treated back surface of the first plastic substrate. The treatment may include applying a polyurethane resin to the surface of the first plastic substrate. The method may further include treating the surface of the second plastic substrate. The method may further include applying an activator to the treated surfaces of the first plastic substrate and the second plastic substrate, and laminating the treated surfaces of the first plastic substrate and the second plastic substrate by juxtaposing them.

Description

Technical Field

[0001] The present disclosure relates to functional laminates for applications in optical devices and optical lenses, particularly functional thermoplastic polyurethane laminates.

Background Art

[0002] Functional films and / or photochromic films can be used to protect or impart various optical properties to optical devices and lenses. Functional films can provide mechanical and general functional properties such as polarization, color, ultraviolet protection, blue cut properties, photochromic properties and / or electrochromic properties. Photochromic films can provide photochromic properties. However, due to their soft texture, both sides of the functional film and / or photochromic film are typically laminated with an optical thermoplastic film to provide the rigidity required for further processing and application. For example, when implemented on the curved surface of an optical lens, the produced polymer laminate must have sufficient integrity to ensure adhesion between the thermoplastic films of the laminate and to avoid delamination or interlayer separation during cutting and forming.

[0003] Such adhesion between the functional film and / or photochromic film and the optical thermoplastic film is typically achieved using an adhesive. Often, the adhesive can be cured using either a heat or ultraviolet (UV) curing process. For example, commercially available adhesives such as UV curable acrylic-based adhesives and polyurethane-based adhesives are used to bond the functional film and / or photochromic film to the thermoplastic film in the laminate. In some cases, film treatments such as corrosive treatment, plasma treatment or corona treatment are performed, although complex processes and costly equipment are required.

[0004] However, these approaches, in addition to having a high impact on the environment, lead to limitations and drawbacks that affect their applicability. For example, due to the sensitivity of certain functional films and / or photochromic films to moisture and heat, bubbles can occur during thermosetting at high temperatures (e.g., 80°C to 100°C), resulting in aesthetic issues. In another example, due to the sensitivity of certain functional films and / or photochromic films to UV light, yellowing of the film can occur during UV curing, showing an unpleasant aesthetic value.

Summary of the Invention

Problems to be Solved by the Invention

[0005] Therefore, while adhesives and methods for preparing functional film-containing laminates exist, there is a continuing need for improvement in this field, at least considering the above drawbacks of current approaches.

[0006] The above "Background" description is intended to generally present the situation of the present disclosure. Aspects of the description that are not qualifying as prior art as of the filing date in terms of the efforts of the inventors within the scope described in this background section and other points are not recognized as prior art to the present disclosure, either explicitly or implicitly.

Means for Solving the Problems

[0007] The present disclosure relates to a method for preparing a laminated optical device.

[0008] In one embodiment, the present disclosure relates to a method for preparing a laminate or a laminated lens, comprising obtaining a first plastic substrate having a front surface and a back surface, treating the front surface or the back surface of the first plastic substrate, and laminating a second plastic substrate onto the treated front surface or the treated back surface of the first plastic substrate, wherein the treatment comprises applying a polyurethane resin to the front surface or the back surface of the first plastic substrate, the applied polyurethane resin is a polyester polyurethane resin, a polyether polyurethane resin, or a polycaprolactone resin, and the treatment further comprises applying isopropyl alcohol or methanol in combination with water to the applied polyurethane resin.

[0009] In one embodiment, the present disclosure further relates to a method for preparing a laminate or a laminated lens, comprising obtaining a first plastic substrate having a front surface and a back surface, treating the front surface or the back surface of the first plastic substrate, and laminating a second plastic substrate onto the treated front surface or the treated back surface of the first plastic substrate. The method further comprises treating the front surface or the back surface of the second plastic substrate, and the lamination comprises juxtaposing the treated front surface or the treated back surface of the first plastic substrate and the treated front surface or the treated back surface of the second plastic substrate, and the treatment comprises applying a polyurethane resin to the front surface or the back surface of the first plastic substrate, applying a polyurethane resin to the front surface or the back surface of the second plastic substrate, and applying isopropyl alcohol or methanol in combination with water to the applied polyurethane resin of the first plastic substrate and the applied polyurethane resin of the second plastic substrate.

[0010] The above paragraphs are provided as a general introduction and are not intended to limit the following claims. The described embodiments will be best understood by reference to the following detailed description taken in conjunction with the accompanying drawings, which will afford additional advantages.

[0011] A more complete understanding of the present disclosure and many of the attendant advantages thereof will be readily obtained by reference to the following detailed description, when considered in conjunction with the accompanying drawings.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2A

Figure 2B

Figure 3

Figure 4A

Figure 4B

Figure 5

Figure 6

Modes for Carrying Out the Invention

[0013] As used herein, the terms "a" or "an" are defined as one or more. The term "plurality" as used herein is defined as two or more. The term "another" as used herein is defined as at least two or more. The terms "including" and / or "having" as used herein are defined as comprising (i.e., open terms). References throughout this document to "one embodiment," "a particular embodiment," "an embodiment," "an embodiment aspect," "an example," or similar terms mean that a particular feature, structure, or characteristic described in connection with that embodiment is included in at least one embodiment of the present disclosure. Thus, appearances of such phrases in various places throughout this document are not necessarily all referring to the same embodiment. Further, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments without limitation.

[0014] The terms "about" or "approximately" are defined as being near, as understood by one of ordinary skill in the art. In one non-limiting embodiment, the term is defined to be within 10%, preferably within 5%, more preferably within 1%, and most preferably within 0.5%.

[0015] The terms "laminate" and "laminated lens" or variations of these terms, when used in the claims and / or specification, refer to similar structures.

[0016] The term "substantially" and variations thereof are defined to include ranges within 10%, 5%, 1%, or 0.5%.

[0017] The terms "suppress," "reduce," "prevent," or "avoid" and variations thereof, when used in the claims and / or specification, include any measurable decrease or complete suppression to achieve the desired result.

[0018] The term "effective", when used in the specification and / or claims, means being suitable for achieving the desired, expected, or intended result.

[0019] The processes of the present disclosure can "include", or can "consist essentially of", or can "consist of" the specific ingredients, components, compositions, etc. disclosed throughout this specification.

[0020] The terms "first plastic substrate", "first plastic film", and "film A" can be used interchangeably in the specification and / or claims, but are intended to mean the same or similar materials. The terms "second plastic substrate", "second plastic film", and "film B" can be used interchangeably in the specification and / or claims, but are intended to mean the same or similar materials.

[0021] The terms "TPU photochromic film" and "TPU film" can be used interchangeably in the specification and / or claims, but are intended to mean the same or similar materials.

[0022] It is possible to incorporate a functional film and / or a photochromic film to add additional optical properties to an optical lens. However, due to the typically soft texture of photochromic films and / or functional films, thermoplastic films such as polycarbonate (PC) films or cellulose triacetate (TAC) films are often laminated to both surfaces of the photochromic film and / or functional film to form a laminate having sufficient material strength to withstand the forming process when the laminate is incorporated onto the surface of the optical lens. For example, a thermoplastic polyurethane (TPU) photochromic film has a Shore A hardness of 45 - 85 and thus needs to be laminated by a harder PC film or TAC film to form a suitable laminate for further lens integration.

[0023] For this purpose, FIG. 1 is a schematic view of a molding device for incorporating a laminate on the surface of an optical lens. This molding device can include a first molding surface 145a, a second molding surface 145b, a concave molding insert 141, and a convex molding insert 142. Each of the first molding surface 145a and the second molding surface 145b can include a hollow portion, and the concave molding insert 141 and the convex molding insert 142 can be removably disposed therein. As shown in FIG. 1, the first molding surface 145a including the concave molding insert 141 can be configured to connect with the second molding surface 145b including the convex molding insert 142. When connected, the concave molding insert 141 and the convex molding insert 142 can form a cavity connected to a hollow line formed by the joining of the first and second molding surfaces 145a, 145b. The line can be configured to receive a polymer by, for example, a screw feeder or a similar device. The cavity can be configured to receive a thermoformed laminate wafer 150. The curvature of the concave molding insert 141 and the curvature of the convex molding insert 142 can determine the lens power of the resulting lens. In one embodiment, the optical lens can include PC, polymethyl methacrylate (PMMA), polystyrene, maleic anhydride styrene copolymer, polyamide, thermoplastic urethane, thermosetting polyurethane, polyester, copolyester, polysulfone, cyclic olefin copolymer (OCO), polyphenylene oxide, allyl diglycol carbonate, polythiourethane, episulfur polymer, epoxy, poly(meth)acrylate, polythiomethacrylate, or a combination thereof. With respect to a semi-finished lens, the curvature along the concave surface of the lens is fixed, and the convex surface of the lens can be modified after molding, for example, by grinding or polishing. It should be noted that multiple lines for receiving the polymer can be connected so that the injection of the polymer from the source can fill multiple molding devices in a single injection, enabling the parallel production of multiple lenses.

[0024] Before placement in the forming device and lens integration, a flat laminate wafer formed by the processes described and illustrated herein can be thermoformed, for example by a thermoforming machine, into a spherical dome shape of the thermoformed laminate wafer 150. During thermoforming, the flat laminate wafer can be placed on a heated thermoforming insert, and a vacuum force can be applied to secure the flat laminate wafer to the thermoforming insert. By adjusting the temperature of the applied heat and the applied vacuum force, the flat laminate wafer can be formed into the curved shape of the thermoforming insert to produce the thermoformed laminate wafer 150.

[0025] In one embodiment, the flat laminate wafer, also referred to herein as "functional laminate", "laminate" and "TPU laminate" among other obvious derivatives, can include a first layer 111, a central layer 120 and a second layer 112. In embodiments of the present disclosure, the first layer 111, also referred to herein as "first plastic film", "film A" and "first plastic substrate", can be a thermoplastic film, the central layer 120 can be a functional film and / or a photochromic film, and the second layer 112, also referred to herein as "second plastic film", "film B" and "second plastic substrate", can be a thermoplastic film. The flat laminate wafer will be described in more detail in the remainder of the present disclosure. However, as shown in FIG. 1, by thermoforming the flat laminate wafer, a curved structure having a concave first layer 111 and a convex second layer 112 can be produced. It can be appreciated that known devices and methods can be used to thermoform the flat laminate wafer, for example, a LEMA manufacturing machine that gradually increases the curvature of the flat laminate wafer under the application of heat.

[0026] Several methods are available for manufacturing flat laminate wafers that can withstand the physical requirements of the thermoforming process and the molding device. For example, when the central layer 120 is a TPU photochromic film, several commercially available adhesives such as UV curable acrylic-based adhesives or polyurethane-based adhesives may be used. However, these adhesives require either UV curing or thermal curing, or both, which requires curing energy and a curing device, and thus the overall lamination process is complicated. Further, some aqueous hot melt adhesives used for TPU photochromic laminates with PC or TAC require heat between the laminates and may further require TPU photochromic film treatment prior to lamination.

[0027] Furthermore, some pressure-sensitive adhesives such as tapes that do not require heat, water, or solvents result in laminates with low material strength (<15 N / inch) as determined by adhesion measurements, and thus there is a risk of delamination during lens manufacturing and integration.

[0028] Any alternative to the above mainly relies on mass production performance such as roll-to-roll film lamination processes that are not applicable in smaller scale settings such as laboratories or clinics. Further, for example, to ensure sufficient adhesion of a laminate including a first plastic film, a functional film, and a second plastic film, the roll-to-roll film lamination process needs to be completed almost immediately, which is not feasible.

[0029] From the above, the present disclosure describes a functional laminate that can be used in an injection molding or casting process that enables the integration of functional laminates with optical lenses to provide improved photochromic performance and characteristics to the functional lenses.

[0030] In one embodiment, the functional laminate includes a TPU photochromic film. The functional laminate can be formed without performing film treatments such as heating, UV radiation, or corona treatment or plasma treatment.

[0031] According to one embodiment, a functional laminate such as a photochromic laminate manufactured by the method described herein demonstrates a rapid photochromic fading rate (i.e., t in 30 seconds 0.5 ). Such photochromic laminates have demonstrated good adhesion after injection molding, formulation finishing, and hard coating.

[0032] According to one embodiment, the present disclosure describes a method of applying a functional TPU film on a first plastic film, applying a functional TPU film on a second plastic film, and laminating the first plastic film and the second plastic film at room temperature and pressure. The method may include adding alcohol or alcohol and water to the functional TPU films on the first plastic film and the second plastic film before lamination. After several hours, a strongly bonded functional TPU laminate can be obtained without the need for additional energy and processing. In one example, the first plastic film can be a PC film. In one example, the second plastic film may be the same as or different from the first plastic film. The second plastic film may be a PC film similar to the first plastic film, or a PMMA film or other material different from the first plastic film.

[0033] In one embodiment, the first plastic film can be a thermoplastic film to which a functional TPU film is applied. In one example, the functional TPU film can include a photochromic dye, a blue light cut dye, a UV cut dye, an IR cut dye, or any other functional component. Thus, the functional TPU film can provide polarization, color, UV protection, etc.

[0034] In one embodiment, the second plastic film can be a thermoplastic film to which a functional TPU film is applied. In one example, the functional TPU film can include a photochromic dye, a blue light cut dye, a UV cut dye, an IR cut dye, or any other functional component. Accordingly, the functional TPU film can provide polarization, color, UV protection, etc.

[0035] In one embodiment, the functional TPU film can be applied to the first plastic film and the second plastic film, among other things, by extrusion, coating, and pre-laminating. Each of the first plastic film and the second plastic film can have a thickness of 20 μm to 10 mm. The functional TPU film can have a thickness of 0.5 μm to 500 μm.

[0036] According to one embodiment, the first plastic film and the second plastic film can each include a photochromic dye, a blue light cut dye, a UV cut dye, an IR cut dye, or any other functional component.

[0037] In one embodiment, the first plastic film and the second plastic film can be the same or different materials, and each material is selected from the group including PC, PMMA, TAC, OCO, polyethylene terephthalate (PET), etc.

[0038] According to one embodiment, the method includes applying isopropyl alcohol (IPA), ethanol, methanol, IPA and water, ethanol and water, or methanol and water to the surface of either or both of the first plastic film and the second plastic film.

[0039] According to one embodiment, the method includes applying a pressure of 2 psi to 80 psi during lamination.

[0040] According to one embodiment, the lamination can be carried out at room temperature (e.g., 25 °C) for a period of 2 hours to 24 hours.

[0041] According to one embodiment, the lamination provides adhesion between TPU laminate layers in the range of 15 N / inch to 80 N / inch, or more preferably in the range of 20 N / inch to 60 N / inch, or more preferably in the range of 30 N / inch to 50 N / inch.

[0042] Referring now to the figures, the method described herein is described with respect to FIG. 2A. Process 200 provides a flow diagram for creating a flat laminated wafer introduced in FIG. 1 that does not require heat curing, UV curing, etc. Here, the functional TPU film is applied to only one of the first plastic film and the second plastic film.

[0043] In step 225 of process 200, a first plastic film or a first plastic substrate having a front and a back can be provided. In one embodiment, the first plastic film can be PC, PMMA, TAC, OCO, PET, polyamide, nylon, allyl diglycol carbonate, thio-urethane copolymer, polyacrylate, polyepisulfide, polyepoxy, polyamide, or a combination thereof.

[0044] In sub-process 230 of process 200, the front or back surface of the first plastic film can be processed. In one embodiment, the processing can include the application of a functional film and / or a photochromic film that provides additional optical qualities such as a polarization function under a specific wavelength. The functional film and / or the photochromic film can be applied to the front or back surface of the first plastic film by extrusion, coating, pre-laminating, or the like. In one embodiment, the processing can include the application of an activator to the front or back surface of the first plastic film. In one embodiment, the processing can include the application of an activator to the applied functional film and / or photochromic film. The activator can be, for example, an alcohol similar to those used to disinfect medical devices. Sub-process 230 of process 200 will be described in more detail with respect to FIG. 2B.

[0045] In step 235 of process 200, a second plastic film or a second plastic substrate having a front and a back surface can be provided and laminated by the processed surface of the first plastic film. In one embodiment, the second plastic film can be PC, PMMA, TAC, OCO, PET, polyamide, nylon, allyl diglycol carbonate, thiourethane copolymer, polyacrylate, polyepisulfide, polyepoxy, polyamide, or a combination thereof.

[0046] According to one embodiment, the lamination can be carried out at room temperature (e.g., 25 °C) under a pressure of 2 psi to 80 psi, more preferably 2 psi to 30 psi. Pressure can be applied to ensure contact between the juxtaposed surfaces of the treated first plastic film and the second plastic film. The pressure can be maintained for the time required for the lamination to be achieved. For example, the lamination time can be 2 hours to 24 hours. However, it can be recognized that depending on the specific materials involved and their specific chemistry, the lamination time can be outside the time range specified above.

[0047] After lamination in step 235 of process 200, the adhesion between the layers of the functional lamination can be evaluated. In one example, when measured by a pull-off adhesion test, the functional lamination can have an adhesion strength or adhesion level in any range and value between including 5 N / inch to 80 N / inch, or 5 N / inch to 10 N / inch, 10 N / inch to 15 N / inch, 15 N / inch to 20 N / inch, 20 N / inch to 25 N / inch, 25 N / inch to 30 N / inch, 30 N / inch to 35 N / inch, 35 N / inch to 40 N / inch, 40 N / inch to 45 N / inch, and 45 N / inch to 50 N / inch, 50 N / inch to 55 N / inch, 55 N / inch to 60 N / inch, 60 N / inch to 65 N / inch, 65 N / inch to 70 N / inch, 70 N / inch to 75 N / inch and 75 N / inch to 80 N / inch. Preferably, the adhesion strength of the functional lamination is greater than 20 N / inch.

[0048] Referring now to FIG. 2B, sub-process 230 of process 200 is described in more detail.

[0049] In step 231 of sub - process 230, the polyurethane resin as a functional film and / or a photochromic film can be applied to the front surface or the back surface of the first plastic film. To provide additional optical quality, the polyurethane resin can contain a dye. The dye can be one of a photochromic dye, a dichroic dye, a blue - cut dye, an infrared - cut dye, an ultraviolet - cut dye, a selective - wavelength - cut dye, a coloring - enhancing dye, an optical - filter dye, or a combination thereof. When applied, the polyurethane resin can have a thickness of 0.5 μm to 500 μm. In one embodiment, the polyurethane resin can be a polyester polyurethane resin, a polyether polyurethane resin, or a polycaprolactone resin.

[0050] In step 232 of sub - process 230, the activator can be applied to the polyurethane resin applied on the surface of the first plastic film. As previously introduced, the activator can be, in one example, an alcohol similar to that used to disinfect medical devices. The activator can be, when advantageous, a material that removes debris from the surface of the polyurethane resin. The application of the activator can be performed as a wipe or a rinse, and at least a part of the remaining activator is removed by evaporation or a similar manner before lamination.

[0051] According to one embodiment, the activator can be a combination of alcohol and water. The combination of alcohol and water ensures that at least a part of the activator remains between the laminates. Thus, the activator contains water to reduce air pockets formed between the surfaces of the first plastic film and the second plastic film during lamination. In one embodiment, the activator can be pure alcohol, and water can be applied after the application of the activator to reduce air pockets formed between the surfaces of the first plastic film and the second plastic film during lamination.

[0052] According to one embodiment, the active agent can be, among others, IPA, ethanol, and methanol, or a combination of IPA and water, ethanol and water, or methanol and water. In one embodiment, the active agent is IPA containing 60 v / v% to 90 v / v% alcohol in purified water.

[0053] In one embodiment, the treatment of the first plastic film described in sub-process 230 of process 200 can enable the formation of hydrogen bonds at the interface between the first plastic film and the second plastic film in step 235 of process 200. The improved hydrogen bonds between the first plastic film and the second plastic film, which can be based on the purity of the polyurethane resin, result in improved adhesion between the first plastic film and the second plastic film compared to laminates manufactured using conventional methods.

[0054] Referring now to FIG. 3, an illustration of the flow diagrams of FIGS. 2A and 2B is shown. The surface of the first plastic film 311 can be treated in sub-process 230 of process 200. This treatment can include, for example, the application of a functional film and / or a photochromic film 320 to the surface of the first plastic film 311. The treated surface of the first plastic film 311 can be juxtaposed with the surface of the second plastic film 312. In step 235 of process 200, the juxtaposition can be performed under pressure to laminate the first plastic film 311, the functional film and / or the photochromic film 320, and the second plastic film 312.

[0055] The above method applies a functional film and / or a photochromic film onto the surface of either the first plastic film or the second plastic film. Therefore, it can be recognized that by applying the functional film and / or the photochromic film onto the juxtaposed surfaces of both the first plastic film and the second plastic film, the adhesion therebetween can be altered. The adhesion achieved during the above laminating process of FIGS. 2A, 2B and 3 is sufficient for use in the application of lenses after injection molding or casting, while FIGS. 4A, 4B and 5 describe a laminating process in which the respective surfaces of the first plastic film and the second plastic film are treated to adjust the mechanical properties for the requirements of specific issues.

[0056] Referring now to FIG. 4A, process 400 shows a flow diagram for creating the flat laminate wafer introduced in FIG. 1, where a functional TPU film is applied to the respective surfaces of the first plastic film and the second plastic film without the need for heat curing, UV curing, etc.

[0057] In step 465 of process 400, a first plastic film or a first plastic substrate having a front surface and a back surface may be provided. In one embodiment, the first plastic film can be PC, PMMA, TAC, OCO, PET, polyamide, nylon, allyl diglycol carbonate, thio-urethane copolymer, polyacrylate, polyepisulfide, polyepoxy, polyamide or a combination thereof.

[0058] In step 470 of process 400, a second plastic film or a second plastic substrate having a front surface and a back surface may be provided. In one embodiment, the second plastic film can be PC, PMMA, TAC, OCO, PET, polyamide, nylon, allyl diglycol carbonate, thiourethane copolymer, polyacrylate, polyepisulfide, polyepoxy, polyamide or a combination thereof.

[0059] In sub - process 475 of process 400, the front or the back of the first plastic film can be processed, and the front or the back of the second plastic film can be processed. In one embodiment, the processing can include the application of a functional film and / or a photochromic film that provides additional optical quality. The functional film and / or the photochromic film can be applied to the front or the back of the first plastic film and the front or the back of the second plastic film by extrusion, coating, pre - lamination, etc. In one embodiment, the processing can include the application of an activator to the front or the back of the first plastic film and the front or the back of the second plastic film. In one embodiment, the processing can include the application of an activator to the applied functional film and / or photochromic film. The activator can be, in one example, an alcohol similar to that used to disinfect medical devices. Sub - process 475 of process 400 will be described in more detail with respect to FIG. 4B.

[0060] In step 480 of process 400, the lamination of the first plastic film and the second plastic film can be performed by the juxtaposition of the processed surfaces of the first plastic film and the second plastic film.

[0061] According to one embodiment, the lamination can be carried out at room temperature (e.g., 25 °C) and under a pressure of 2 psi to 80 psi, more preferably 2 psi to 30 psi. Pressure can be applied to ensure contact between the juxtaposed treatment surfaces of the first plastic film and the second plastic film. The pressure can be maintained for the time required for the lamination to be achieved. For example, the lamination time can be 2 hours to 24 hours. However, it can be recognized that depending on the specific materials involved and their specific chemistry, the lamination time can be outside the time range specified above.

[0062] After lamination in step 480 of process 400, the adhesion between the layers of the functional lamination can be evaluated. In one example, when measured by a pull-off adhesion test, the functional lamination can have an adhesion strength or adhesion level within any range and value between 5 N / inch to 80 N / inch, or 5 N / inch to 10 N / inch, 10 N / inch to 15 N / inch, 15 N / inch to 20 N / inch, 20 N / inch to 25 N / inch, 25 N / inch to 30 N / inch, 30 N / inch to 35 N / inch, 35 N / inch to 40 N / inch, 40 N / inch to 45 N / inch, and 45 N / inch to 50 N / inch, 50 N / inch to 55 N / inch, 55 N / inch to 60 N / inch, 60 N / inch to 65 N / inch, 65 N / inch to 70 N / inch, 70 N / inch to 75 N / inch and 75 N / inch to 80 N / inch. Preferably, the adhesion strength of the functional lamination is greater than 20 N / inch.

[0063] Now, referring to FIG. 4B, sub-process 475 of process 400 will be described in more detail.

[0064] Similar to FIG. 2B, in step 476 of sub-process 475, the polyurethane resin as a functional film and / or a photochromic film can be applied to the front surface of the first plastic film or the back surface of the first plastic film and the front surface of the second plastic film or the back surface of the second plastic film. To provide additional optical quality, the polyurethane resin can contain a dye. The dye can be one of a photochromic dye, a dichroic dye, a blue cut dye, an infrared cut dye, an ultraviolet cut dye, a selective wavelength cut dye, a coloring enhancement dye, a light filter dye, or a combination thereof. When applied, the polyurethane resin can have a thickness of 0.5 μm to 500 μm. In one embodiment, the polyurethane resin can be a polyester polyurethane resin, a polyether polyurethane resin, or a polycaprolactone resin.

[0065] In step 477 of sub-process 475, the activator can be applied to the polyurethane resin applied to the surface of the first plastic film and the polyurethane resin applied to the surface of the second plastic film. As previously introduced, the activator can be, in one example, an alcohol similar to that used to disinfect a medical device. The activator can be, when advantageous, a material that removes debris from the polyurethane resin applied to the surface of the first plastic film and the polyurethane resin applied to the surface of the second plastic film. The application of the activator can be performed as a wipe or a rinse, and at least a portion of the remainder of the activator is removed by evaporation or a similar manner prior to lamination.

[0066] According to one embodiment, the activator can be a combination of alcohol and water. The combination of alcohol and water ensures that at least a portion of the activator remains between the laminates. Thus, the activator contains water to reduce air pockets formed between the treatment surfaces of the first plastic film and the second plastic film between the laminates. In one embodiment, the activator can be pure alcohol, and water can be applied after the application of the activator to reduce air pockets formed between the treatment surfaces of the first plastic film and the second plastic film between the laminates.

[0067] According to one embodiment, the activator can be, among others, IPA, ethanol, and methanol, or a combination of IPA and water, ethanol and water, or methanol and water. In one embodiment, the activator is IPA containing 60 v / v% to 90 v / v% alcohol in purified water.

[0068] In one embodiment, the treatment of the first plastic film and the second plastic film described in sub-process 475 of process 400 enables the formation of hydrogen bonds at the interface between the treatment surface of the first plastic film and the treatment surface of the second plastic film in step 480 of process 400. The improved hydrogen bonding between the treatment surfaces of the first plastic film and the second plastic film, which can be based on the purity of the polyurethane resin, results in improved adhesion between the first plastic film and the second plastic film compared to laminates manufactured using conventional methods.

[0069] Referring now to FIG. 5, an illustration of the flow diagrams of FIGS. 4A and 4B is shown. The surface of the first plastic film 511 can be processed in sub-process 475 of process 400. This processing can include, for example, the application of a functional film and / or a photochromic film 520 to the surface of the first plastic film 511, as well as the application of an activator. Similarly, the surface of the second plastic film 512 can be processed in sub-process 475 of process 400. This processing can include, for example, the application of a functional film and / or a photochromic film 520' to the surface of the second plastic film 512, as well as the application of an activator. The processed surface of the first plastic film 511 can be juxtaposed with the processed surface of the second plastic film 512. In step 480 of process 400, the juxtaposition can be carried out under pressure to laminate the first plastic film 511, the functional film and / or the photochromic films 520, 520', and the second plastic film 512.

[0070] The function of the above functional laminate is provided by a polyurethane resin, but it can be recognized that it can be the first plastic film and / or the second plastic film that provides the function. It can also be a combination that provides the function.

[0071] By implementing the above method, a number of types of laminates can be manufactured in a simple way without including chemical adhesives, heating and / or UV curing.

[0072] As part of this disclosure, specific examples are included below. These examples are for illustrative purposes only and are not intended to limit the invention. In fact, these examples may not be exemplary embodiments of the disclosure, but instead are intended to provide a comparison between non-limiting examples of the disclosure and other implementations in the art. Those skilled in the art will readily recognize parameters that can be varied or modified to obtain essentially the same results.

[0073] References to "laminating overnight" may generally be described as "drying", as in the case of Figure 6. The "type of adhesion" may be similar to the "type of activator". In such "drying", the drying time, as well as the pressure applied during drying, may be defined. For example, the drying time may be from 2 hours to 24 hours, and the pressure applied may be from 3 psi to 30 psi. The ranges defined above are merely exemplary ranges, and it can be recognized that other ranges, including or excluded from the above, may be implemented to achieve the flat laminate wafers described in the present disclosure.

Example

[0074] Example 1 (Preparation of Photochromic PC-TPU-TPU-PC Laminate by IPA) A photochromic TPU resin (Pellethane 80A 2363 with a photochromic dye from Transitions Inc) was extruded onto a polycarbonate film to obtain a roll of PC-TPU film with a TPU thickness of about 150 μm. Then, wafers with a diameter of 76 mm were punched out from this film roll. Thereafter, the two TPU surfaces of the wafers were wiped with IPA and then laminated on top of each other overnight at room temperature (e.g., 25 °C) and 30 psi in the presence of IPA. Thermal curing was not applied. After about 24 hours, a photochromic PC-TPU-TPU-PC laminate wafer with strong adhesion between TPU-TPU and a peel strength higher than 50 N / inch (i.e., adhesion level) was obtained (see Figure 6).

[0075] Example 2 (Preparation of Photochromic PC-TPU-TPU-PC Laminate by IPA + Water) A photochromic TPU resin similar to that of Example 1 was extrusion molded onto a PC film to obtain a PC-TPU film roll. Subsequently, wafers with a diameter of 76 mm were punched out from this film roll. Then, the two TPU surfaces were wiped with IPA and then laminated on top of each other overnight at room temperature (e.g., 25 °C) and 30 psi in the presence of water. Heat curing was not applied. After about 24 hours, a photochromic PC-TPU-TPU-PC laminate wafer having strong adhesion between TPU and a peel strength higher than 25 N / inch (i.e., adhesion level) was obtained (see Figure 6).

[0076] Example 3 (Preparation of Photochromic PC-TPU-TPU-PC Laminate with Methanol) A photochromic TPU resin similar to that of Example 1 was extrusion molded onto a PC film as a PC-TPU film roll. Subsequently, wafers with a diameter of 76 mm were punched out from this film roll. Then, the TPU surfaces were wiped with methanol and then laminated on top of each other overnight at room temperature (e.g., 25 °C) and 30 psi in the presence of methanol. Heat curing was not applied. After about 24 hours, a photochromic PC-TPU-TPU-PC laminate wafer having strong adhesion between TPU-TPU and a peel strength higher than 50 N / inch (i.e., adhesion level) was obtained (see Figure 6).

[0077] Example 4 (Preparation of Photochromic PC-TPU-PC Laminate for Injection Molding) A photochromic TPU resin similar to that of Example 1 was extruded onto a PC film as a PC-TPU film roll. Subsequently, a wafer with a diameter of 76 mm was punched out from this film roll. Then, the TPU surface was wiped with IPA, and then laminated onto another PC film at room temperature (e.g., 25 °C) and 30 psi overnight in the presence of IPA and water. Thermal curing was not applied. After about 24 hours, a photochromic PC-TPU-PC laminated wafer was obtained. Then, using a LEMA machine, the laminated wafer was thermoformed into a 4.0D base wafer and then injection molded to obtain a PC photochromic semi-finished lens with very good adhesion. No delamination occurred during the surface process to a -2.0D lens.

[0078] Example 5 (Preparation of a photochromic TPU-TPU laminate with a PET release liner) The same photochromic TPU resin as in Example 1 was extruded onto a PET release liner to obtain a TPU film roll. After removing the liner on one side, the two TPU films were wiped with IPA and then laminated onto each other at room temperature (e.g., 25 °C) and 30 psi overnight in the presence of IPA. Thermal curing was not applied. After about 24 hours, a photochromic TPU-TPU laminated wafer with very strong adhesion and a peel strength of about 50 N / inch (i.e., adhesion level) was obtained (see Figure 6).

[0079] Comparative Example 1 (Preparation of a photochromic TPU-TPU laminate with a silicone release liner) The same photochromic TPU resin as in Example 1 was extruded onto a silicone release liner. After removing the liner, the two TPU films were wiped with IPA and then laminated onto each other at room temperature (e.g., 25 °C) and 30 psi overnight in the presence of IPA. Thermal curing was not applied. Due to the presence of a trace amount of silicone on the TPU surface, the adhesion at the TPU-TPU interface was very poor and showed a peel strength of about 0 N / inch (i.e., adhesion level).

[0080] Comparative Example 2 (Preparation of Photochromic TPU-TPU Laminate with Only Water) The same photochromic TPU resin as in Example 1 was extrusion molded onto a PC film as a PC-TPU film roll. Subsequently, a wafer with a diameter of 76 mm was punched out from this film roll. Then, the TPU surface was wiped with water and then laminated on top of each other at room temperature (e.g., 25 °C) and 30 psi overnight in the presence of water. Thermal curing was not applied. Due to the presence of water on the TPU surface, the adhesion at the TPU-TPU interface was very poor and showed a peel strength of approximately 0 N / inch (i.e., adhesion level) (see Figure 6).

[0081] Comparative Example 3 (Preparation of Photochromic TPU-TPU Laminate by Corona Treatment + Water) The same photochromic TPU resin as in Comparative Example 2 was extrusion molded onto a PC film as a PC-TPU film roll. Subsequently, a wafer with a diameter of 76 mm was punched out from this film roll. Then, the TPU surface was corona treated (for the purpose of promoting adhesion) and then laminated on top of each other at room temperature (e.g., 25 °C) and 30 psi overnight in the presence of water. Thermal curing was not applied. Due to the presence of water on the TPU surface, the adhesion at the TPU-TPU interface was very poor and showed a peel strength of approximately 0 N / inch (i.e., adhesion level) (see Figure 6).

[0082] Comparative Example 4 (Preparation of Photochromic TPU-TPU Laminate with IPA + Water-Based HMA) The same photochromic TPU resin as Comparative Example 2 was extrusion molded onto a PC film as a PC-TPU film roll. Next, a wafer with a diameter of 76 mm was die-cut from this film roll. Then, the two TPU surfaces were wiped with IPA and then laminated on top of each other at room temperature (e.g., 25 °C) and 30 psi overnight in the presence of a water-based hot melt adhesive (HMA) (UD-104 from Bondpolymer Inc). Thermal curing was not applied. Due to the presence of the water-based HMA on the TPU surface, the adhesion at the TPU-TPU interface was very poor and showed a peel force of about 0 N / inch (i.e., adhesion level) (see Figure 6).

[0083] According to one embodiment, the method of the present disclosure is feasible within the scope of roll-to-roll manufacturing of photochromic laminates. These laminates can then be used in a conventional injection molding process to produce photochromic semi-finished or finished lenses with high photochromic performance.

[0084] According to one embodiment, the method of the present disclosure is feasible on a small scale (e.g., in a retail store or laboratory) because the described process does not require heat and / or UV radiation therein.

[0085] According to one embodiment, the method of the present disclosure is feasible within the scope of other film lamination techniques for producing laminates with added value for applications in optical lenses, including photochromic laminates, or other optically functional laminates, such as optical microstructured laminates, from transparent to polarized laminates.

[0086] Obviously, many changes and modifications are possible in view of the above teachings. Therefore, it should be understood that the invention may be practiced in ways other than those specifically described herein within the scope of the appended claims.

[0087] Embodiments of the present disclosure can also be described in the following description.

[0088] A method for preparing a laminate, comprising: obtaining a first plastic substrate having a front surface and a back surface; treating the front surface or the back surface of the first plastic substrate; and laminating a second plastic substrate onto the treated front surface or the treated back surface of the first plastic substrate.

[0089] The method according to (1), wherein the treatment comprises applying a polyurethane resin to the front surface or the back surface of the first plastic substrate.

[0090] The method according to either (1) or (2), wherein the applied polyurethane resin is a polyester polyurethane resin, a polyether polyurethane resin, or a polycaprolactone resin.

[0091] The method according to any one of (1) to (3), wherein the applied polyurethane resin contains at least one dye selected from the group consisting of a photochromic dye, a dichroic dye, a blue cut dye, an infrared cut dye, an ultraviolet cut dye, a selective wavelength cut dye, a coloring enhancing dye, and a light filter dye.

[0092] The method according to any one of (1) to (4), wherein the applied polyurethane resin has a thickness of 0.5 micron to 500 microns.

[0093] The method according to any one of (1) to (5), wherein the treatment comprises applying isopropyl alcohol or methanol in combination with water to the applied polyurethane resin.

[0094] The method according to any one of (1) to (5), wherein the treatment comprises applying isopropyl alcohol, ethanol, or methanol to the applied polyurethane resin, and preferably, the treatment comprises applying isopropyl alcohol combined with water, ethanol combined with water, or methanol combined with water to the applied polyurethane resin.

[0095] (8) A method according to any one of (1) to (7), wherein the lamination is carried out at room temperature.

[0096] (9) A method according to any one of (1) to (8), wherein the lamination is carried out at 2 to 30 psi.

[0097] (10) A method according to any one of (1) to (9), wherein the first plastic substrate comprises at least one selected from the group consisting of polycarbonate, cellulose triacetate, polymethyl methacrylate, polyamide, polyethylene terephthalate, cyclic olefin copolymer, nylon, allyl diglycol carbonate, thiourethane copolymer, polyacrylate, poly - episulfide, epoxy resin and polyamide.

[0098] (11) A method according to any one of (1) to (10), wherein the second plastic substrate comprises at least one selected from the group consisting of polycarbonate, cellulose triacetate, polymethyl methacrylate, polyamide, polyethylene terephthalate, cyclic olefin copolymer, nylon, allyl diglycol carbonate, thiourethane copolymer, polyacrylate, poly - episulfide, epoxy resin and polyamide.

[0099] (12) A method according to any one of (1) to (11), wherein the treatment of the front or back surface of the first plastic substrate enables the formation of hydrogen bonds at the interface between the treated surfaces of the first and second plastic substrates.

[0100] (13) A method according to any one of (1) to (12), wherein each of the obtained first and second plastic substrates has a thickness of 20 microns to 10 millimeters.

[0101] (14) Further comprising treating the front surface or the back surface of the second plastic substrate, the laminate including juxtaposing the treated front surface or the treated back surface of the first plastic substrate and the treated front surface or the treated back surface of the second plastic substrate, the method according to any one of (1) to (13).

[0102] (15) The treatment includes applying a polyurethane resin to the front surface or the back surface of the first plastic substrate, applying a polyurethane resin to the front surface or the back surface of the second plastic substrate, and applying isopropyl alcohol or methanol in combination with water to the applied polyurethane resin of the first plastic substrate and the applied polyurethane resin of the second plastic substrate, the method according to any one of (1) to (14).

[0103] (16) The polyurethane resin includes at least one dye selected from the group consisting of a photochromic dye, a dichroic dye, a blue cut dye, an infrared cut dye, an ultraviolet cut dye, a selective wavelength cut dye, a coloring enhancement dye, and a light filter dye, the method according to any one of (1) to (15).

[0104] Therefore, the above discussion discloses and describes merely exemplary embodiments of the present invention. As will be understood by those skilled in the art, the present invention may be embodied in other specific forms without departing from the spirit or essential characteristics of the present invention. Accordingly, the disclosure of the present invention is intended as an illustration rather than a limitation of the scope of the present invention and other claims. The present disclosure partially defines the scope of the terms of the above claims so as not to embrace the spirit of the present invention in any readily recognizable variations of the teachings herein. The present disclosure includes the following aspects of the invention: <Aspect 1> Obtaining a first plastic substrate having a front surface and a back surface, Processing the front surface of the first plastic substrate or the back surface of the first plastic substrate, Laminating a second plastic substrate onto the processed front surface of the first plastic substrate or the processed back surface of the first plastic substrate A method for preparing a laminate, comprising. <Aspect 2> The method according to aspect 1, wherein the processing includes applying a polyurethane resin to the front surface of the first plastic substrate or the back surface of the first plastic substrate. <Aspect 3> The method according to aspect 2, wherein the applied polyurethane resin is a polyester polyurethane resin, a polyether polyurethane resin or a polycaprolactone resin. <Aspect 4> The method according to aspect 2, wherein the applied polyurethane resin contains at least one dye selected from the group consisting of a photochromic dye, a dichroic dye, a blue cut dye, an infrared cut dye, an ultraviolet cut dye, a selective wavelength cut dye, a coloring enhancing dye and a light filter dye. <Aspect 5> The method according to aspect 2, wherein the applied polyurethane resin has a thickness of 0.5 microns to 500 microns. <Aspect 6> The method according to aspect 2, wherein the processing includes applying isopropyl alcohol, ethanol or methanol to the applied polyurethane resin, and preferably, the processing includes applying isopropyl alcohol combined with water, ethanol combined with water or methanol combined with water to the applied polyurethane resin. <Aspect 7> The method according to aspect 1, wherein the lamination is performed at room temperature. <Aspect 8> The method according to aspect 1, wherein the lamination is performed at 2 to 30 psi. <Aspect 9> The method according to aspect 1, wherein the first plastic substrate includes at least one selected from the group consisting of polycarbonate, cellulose triacetate, polymethyl methacrylate, polyamide, polyethylene terephthalate, cyclic olefin copolymer, nylon, allyl diglycol carbonate, thiourethane copolymer, polyacrylate, poly-episulfide, epoxy resin and polyamide. <Aspect 10> The method according to aspect 1, wherein the second plastic substrate contains at least one selected from the group consisting of polycarbonate, cellulose triacetate, polymethyl methacrylate, polyamide, polyethylene terephthalate, cyclic olefin copolymer, nylon, allyl diglycol carbonate, thiourethane copolymer, polyacrylate, poly-episulfide, epoxy resin, and polyamide. <Aspect 11> The method according to aspect 1, wherein the treatment of the front surface or the back surface of the first plastic substrate enables the formation of hydrogen bonds at the interface between the treated surfaces of the first plastic substrate and the second plastic substrate. <Aspect 12> The method according to aspect 1, wherein each of the obtained first plastic substrate and the second plastic substrate has a thickness of 20 microns to 10 millimeters. <Aspect 13> Further comprising treating the front surface or the back surface of the second plastic substrate and The method according to aspect 1, wherein the lamination includes juxtaposing the treated front surface or the treated back surface of the first plastic substrate and the treated front surface or the treated back surface of the second plastic substrate. <Aspect 14> The treatment comprises applying a polyurethane resin to the front surface or the back surface of the first plastic substrate, applying a polyurethane resin to the front surface or the back surface of the second plastic substrate, and applying isopropyl alcohol or methanol in combination with water to the applied polyurethane resin of the first plastic substrate and the applied polyurethane resin of the second plastic substrate. The method according to aspect 13. <Aspect 15> The method according to aspect 14, wherein the polyurethane resin contains at least one dye selected from the group consisting of photochromic dyes, dichroic dyes, blue cut dyes, infrared cut dyes, ultraviolet cut dyes, selective wavelength cut dyes, color intensifying dyes, and optical filter dyes.

Claims

1. obtaining a first plastic substrate having a front surface and a back surface; treating the front surface of the first plastic substrate or the back surface of the first plastic substrate; laminating a second plastic substrate onto the treated front surface of the first plastic substrate or the treated back surface of the first plastic substrate; comprising wherein the treatment includes applying a polyurethane resin to the front surface of the first plastic substrate or the back surface of the first plastic substrate, and applying isopropyl alcohol, ethanol or methanol to the applied polyurethane resin; wherein the lamination is carried out at room temperature; wherein each of the obtained first plastic substrate and the second plastic substrate has a thickness of 20 microns to 10 millimeters; A method for preparing a laminate.

2. The method according to claim 1, wherein the applied polyurethane resin is a polyester polyurethane resin or a polyether polyurethane resin.

3. The method according to claim 1, wherein the applied polyurethane resin contains at least one dye selected from the group consisting of a photochromic dye, a dichroic dye, a blue cut dye, an infrared cut dye, an ultraviolet cut dye, a selective wavelength cut dye, a color intensifying dye and a light filter dye.

4. The method according to claim 1, wherein the applied polyurethane resin has a thickness of 0.5 microns to 500 microns.

5. The method according to claim 1, wherein applying isopropyl alcohol, ethanol or methanol includes applying a combination of isopropyl alcohol and water, a combination of ethanol and water, or a combination of methanol and water to the applied polyurethane resin.

6. The method according to claim 1, wherein the lamination is carried out at 2 to 30 psi. **Claim 7** The method according to claim 1, wherein the first plastic substrate comprises at least one selected from the group consisting of polycarbonate, cellulose triacetate, polymethyl methacrylate, polyethylene terephthalate, cyclic olefin copolymer, nylon, allyl diglycol carbonate, thiourethane copolymer, polyacrylate, poly-episulfide, polyepoxy and polyamide. **Claim 8** The method according to claim 1, wherein the second plastic substrate comprises at least one selected from the group consisting of polycarbonate, cellulose triacetate, polymethyl methacrylate, polyethylene terephthalate, cyclic olefin copolymer, nylon, allyl diglycol carbonate, thiourethane copolymer, polyacrylate, poly-episulfide, polyepoxy and polyamide. **Claim 9** The method according to claim 1, wherein the treatment of the front surface or the back surface of the first plastic substrate enables the formation of hydrogen bonds at the interface between the treated surfaces of the first plastic substrate and the second plastic substrate. **Claim 10** treating the front surface or the back surface of the second plastic substrate further comprising The method according to claim 1, wherein the lamination comprises juxtaposing the treated front surface or the treated back surface of the first plastic substrate and the treated front surface or the treated back surface of the second plastic substrate. **Claim 11** The treatment of the front surface or the treatment of the back surface of the second plastic substrate is applying a polyurethane resin to the front surface or the back surface of the second plastic substrate; Applying isopropyl alcohol, ethanol or methanol, or a combination of isopropyl alcohol and water, ethanol and water, or methanol and water to the applied polyurethane resin of the second plastic substrate The method according to claim 10, comprising this.

12. The method according to claim 11, wherein the polyurethane resin applied to the front surface of the second plastic substrate or the back surface of the second plastic substrate contains at least one dye selected from the group consisting of a photochromic dye, a dichroic dye, a blue cut dye, an infrared cut dye, an ultraviolet cut dye, a selective wavelength cut dye, a coloring enhancement dye, and a light filter dye.

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