The present invention relates to forming a decorative appearance on a laminate structure and, more particularly, to a process for making a curved laminated solar panel having a decorative appearance using distortion printing.
The forming of a decorative appearance on solar panels presents challenges when adapted to a solar panel having two-axes of curvature, such as, for example, a vehicle or architectural panel having a curved, complex shape. Conventional systems and methods for creating patterns and designs in flat solar panel applications typically employ a transfer sheet, backsheet, or other separately patterned layer. Alternatively, the image may be applied to the solar panel directly. In either case, the pattern may be applied with a suitable printer, such as, for example, a gantry-style printing apparatus. The layer is applied before or after lamination to rigid, flat panels or flexible, planar panels held in a flat state. Imaging on curved surfaces is generally more challenging than on flat surfaces because standard proximity or contact printing techniques, e.g., gantry-style printers, are not capable of handling curved surfaces. As a result, other techniques have been developed.
Illustrative examples of designs or decorations applied to complex surfaces abound in the packaging industry. In one approach, consumable products such as glass and/or plastic bottles can be decorated with heat shrink films. In this technique a pattern, such as a logo or text, is printed on a layer of clear, heat-shrinkable polymer, which is then cut, formed into an open-ended cylinder, placed over the bottle, and heat-shrunk until it conforms to the bottle surface. A layer of adhesive may be used to provide additional durability for the label. In another approach, ink or paint is applied to the surface of a mold in the shape of the item, followed by injection or blow molding of the glass or plastic. The molten plastic bonds to the ink or paint layer forming a highly durable and scratch-resistant design on its surface. In the blister packaging approach, a design or label is printed on a flat layer of clear packaging, followed by shaping of the layer using the blistering technique, resulting in the label positioned on the blister.
In another approach, plastic thermoforming may be used with a printed decoration or label sheet, either laminated or adhered to a sheet of the packaging material. Plastic thermoforming is the broad label given to the manufacturing process that heats thermoplastic sheet material (i.e., “thermos”) and then applies pressure, force, or vacuum to form into a 3-dimensional shape (i.e., “forming”). Methods of thermoforming may include pressure forming, vacuum forming, drape forming, and sag forming, and may depend on the material composition of the item to be formed. In pressure forming, the sheet of thermoplastic material is heated until pliable and placed over a mold. Positive pressure is then applied above the heated sheet, pressing the material into the surface of the mold to create the desired 3-dimensional shape. In vacuum forming, sheet thermoplastic material is heated until pliable and placed over a mold. The air between the heated sheet and mold is then evacuated creating a vacuum that pulls the material onto the surface of the mold to create the desired 3-dimensional shape. One significant difference is that pressure forming allows for pressures greater than one atmosphere to draw a plastic sheet into its final configuration, whereby the additional pressure allows for greater detail and texture when such aesthetics are desired. Drape forming, or sag forming, employs mechanical or manual draping over a mold and may be generally distinguishable in that it does not substantially stretch the plastic during the formation of the part.
These conventional technologies and methods have disadvantages which become apparent when an undistorted image is first printed on a flat sheet and later takes the form of a 3D surface whence it becomes distorted. In cases where this is undesirable, such as lettering, the image may be pre-distorted to counteract this effect. This compensated printing technique is called distortion printing.
In the automotive space, where designs are applied to a variety of vehicles, the most common techniques for applying designs, decorations, or indicia include standard masking and painting, maskless painting (e.g., airbrushing) and adhesive decals. In recent years two other techniques have emerged for applying protective layers and/or designs. Clear bra is a protective film for vehicles that goes by multiple names, such as invisible shield, car scratch protective film, clear mask, etc. A second technique is called a vinyl wrap. Vinyl wraps are made of heavy-duty vinyl that has an adhesive backing on one side. With the addition of polyvinyl chloride (PVC), the vinyl material is significantly strengthened. This gives rise to the excellent durability of car wraps. For flexibility, plasticizers may be used. In the vinyl wrap technique, the film may be applied to individual body panels or an entire vehicle and conforms upon the application of heat or by virtue of adhesives and may be printed or colored. In the above bra and vinyl wrap examples, an image or design is printed first on the flat film and some distortion of the image occurs when it takes the form of the body panel. The clear bra and vinyl wrap films have lifetimes of between 1 and 5 years, depending on exposure, care and maintenance. Yellowing (clear bra) or peeling (clear bra, vinyl wrap) of the of the film are common failure mechanisms. Thus, these techniques, while capable of producing excellent undistorted images on complex surfaces, are not suitable for an automobile panel that is expected to last for many years.
In view of the harsh environment survivability and durability requirements, there is a need for a method for integrating patterns, labels, and designs with a laminated solar body panel of a desired aerodynamic shape having multiple axes of curvature such as, for example, the roof, hood, or trunk of an automobile. In addition, there exists a long-felt need to be able to form a distortion-free, decorative appearance on laminated solar panels, for example, to improve the appearance of the panel.
The present invention is directed to an article of manufacture and method for producing a decorative appearance on a curved laminated solar panel using distortion printing, the article of manufacture corresponding to a solar panel produced thereby.
In one aspect of the present invention, a method for producing a decorative appearance is described wherein patterns, labels, and/or designs may be applied to a one-or two-axis of curvature, laminated solar panel, in a manner that allows said patterns, labels, and/or designs to appear substantially undistorted.
In another aspect of the present invention, a one-or two-axis of curvature laminated solar panel is produced that is compatible with the requirements of automotive applications, the solar panel having a distortion-free, decorative appearance.
In another aspect of the present invention, a one-or two-axis of curvature laminated solar panel is produced, the solar panel having a distortion-free, decorative appearance that may be mass produced at low cost. Other desirable features and characteristics will become apparent from the abstract, the detailed description, the drawings, and the claims, when considered in view of this summary.
Non-limiting and non-exhaustive embodiments of the present disclosure are described with reference to the following drawings. In the drawings, like numerals describe like components throughout the several views.
For a better understanding of the present disclosure, reference will be made to the following Detailed Description, which is to be read in association with the accompanying drawings, which are incorporated in and constitute a part of this specification, show certain aspects of the subject matter disclosed herein and, together with the description, help explain some of the principles associated with the disclosed implementations, wherein:
Non-limiting embodiments of the invention will be described below with reference to the accompanying drawings, wherein like reference numerals represent like elements throughout. While the invention has been described in detail with respect to the preferred embodiments thereof, it will be appreciated that upon reading and understanding of the foregoing, certain variations to the preferred embodiments will become apparent, which variations are nonetheless within the spirit and scope of the invention. The drawings featured in the figures are provided for the purposes of illustrating some embodiments of the invention and are not to be considered as limitation thereto.
The terms “a” or “an”, as used herein, are defined as one or as more than one. The term “plurality”, as used herein, is defined as two or as more than two. The term “another”, as used herein, is defined as at least a second or more. The terms “including” and/or “having”, as used herein, are defined as comprising (i.e., open language). The term “coupled”, as used herein, is defined as connected, although not necessarily directly, and not necessarily mechanically.
Reference throughout this document to “some embodiments”, “one embodiment”, “certain embodiments”, and “an embodiment” or similar terms means that a particular feature, structure, or characteristic described in connection with the embodiment is included in at least one embodiment of the present invention. Thus, the appearances of such phrases or in various places throughout this specification are not necessarily all referring to the same embodiment. Furthermore, the particular features, structures, or characteristics may be combined in any suitable manner in one or more embodiments without limitation.
The term “or” as used herein is to be interpreted as an inclusive or meaning any one or any combination. Therefore, “A, B or C” means any of the following: “A; B; C; A and B; A and C; B and C; A, B and C”. An exception to this definition will occur only when a combination of elements, functions, steps or acts are in some way inherently mutually exclusive.
The term “means” preceding a present participle of an operation indicates a desired function for which there is one or more embodiments, i.e., one or more methods, devices, or apparatuses for achieving the desired function and that one skilled in the art could select from these or their equivalent in view of the disclosure herein and use of the term “means” is not intended to be limiting.
In an embodiment illustrated in
As described herein and with respect to any of the embodiments of the disclosure, distortion printing may refer to disposing, or otherwise imparting, a design on or proximate to one or more layers of a lamination stack of which the solar panel is comprised. In this context a design may include an image, label, logo, lettering, or any other indicia. Such designs may be decorative or aesthetically pleasing, or be purposed for masking components from view. A design may comprise a pigment, ink, dye, or other coloring. The design may be disposed on one or more layers of the lamination stack. Where a design is disposed on two or more layers, the design may form a 3D image characterized as having depth or other visual components thereof. In a preferred embodiment, the design may be disposed below the solar cells, in this case on the surfaces, within the layers, or at the interfaces of the substrate 120. For disposing a design in or on the lamination stack, the design may be printed or transferred thereto. In the transferring process, there may be a disposable layer that conveys the design from the printer or location or origin to the layer to be disposed thereto. Among the layers of the embodiment shown and described with respect to
The polymer layers for the solar panel 100 may be chosen from a large variety of materials. For example, non-limiting alternatives for the PC include glass, polypropylene (PP), polymethyl methacrylate (PMMA), polyethylene terephthalate (PET), polyvinylchloride (PVC), polyethylene (PE), cyclic olefin copolymer (COC), and Fluorinated ethylene propylene (FEP). Non-limiting alternatives for polyolefin (PO), crossing-linking polyolefin (XPO), polyvinyl butyral (PVB), thermoplastic olefin (TPO), ethylene-vinyl acetate (EVA), silicone, polyvinylidene difluoride (PVDF), and thermoplastic polyurethane (TPU). And non-limiting alternatives for the ETFE layers include ethylene chlorotrifluoroethylene (ECTFE).
In another embodiment, illustrated in
Referring again to
Drying occurs immediately after the ink is printed. Drying may generally be considered as removing the solvent from the mixture; desirable drying occurs without blistering, cracking, or otherwise over-drying. Generally, passive drying takes too long to be economical. Therefore, active methods of drying of coatings, paints, inks, and the like, can be accomplished with convection heating, infrared energy, a combination of convection and infrared, UV energy, and/or forced-air drying. With convection, the air is heated, transferring energy to the coating. Infrared and UV drying provides highly-efficient electromagnetic energy directly from the heat source to the coating without heating the air therebetween. With forced-air drying, air is passed over the coating and convection occurs. In the context of printing multiple layers directly on top of one another, the presence of binder in the initially-disposed ink may facilitate the adhesion or acceptance of the subsequently-disposed layer. The drying process generally enables a subsequent printing of additional layers.
After drying, a firing may be used, which may generally be considered as removing the binder from the mixture, at which point the frit adheres with and/or to the glass. In one embodiment, firing may occur with the glass in a flat state. The flat glass with adhered frit may then be subjected to preforming 168 and strengthening 169, as in
In an alternative embodiment, other layers in the lamination stack may be printed as desired. For example, one or more laminate layers may be combined to create multi-dimensional images to the laminated solar panel 100 by the lamination process. Graphical effects may be accomplished by using the spatial relationship of the multiple layers such as, for example, depth of view, electroluminescent coatings (i.e., layers that can glow or create illuminated lettering), or other graphical layer combinations. Also, printing on layers above the solar cells 200 can be done for various purposes. For example, it can be used to mask defects, it can be used to mask solar cells 200 from view, or it can be used to create a three-dimensional effect.
In an alternative embodiment, a distortion printed image may be applied to an image sheet or transfer film. This sheet or film is added to the bottom surface 128a of the bottom laminate layer 122 of the substrate 120 as shown in
While certain configurations of structures have been illustrated for the purposes of presenting the basic structures of the present invention, one of ordinary skill in the art will appreciate that other variations are possible which would still fall within the scope of the appended claims. Additional advantages and modifications will readily occur to those skilled in the art. Therefore, the invention in its broader aspects is not limited to the specific details and representative embodiments shown and described herein. Accordingly, various modifications may be made without departing from the spirit or scope of the general inventive concept as defined by the appended claims and their equivalents.
This application claims priority to, and the benefit of, co-pending U.S. Provisional Patent Application No. 63/315,784, filed on Mar. 2, 2022, entitled “Process For Making Curved Laminated Solar Panel Having Decorative Appearance Using Distortion Printing And Panel Produced Thereby”, which is incorporated by reference in its entirety.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/US23/63600 | 3/2/2023 | WO |
| Number | Date | Country | |
|---|---|---|---|
| 63315784 | Mar 2022 | US |