Front plane laminate with external surface electrical connections

Abstract

A light-transmissive substrate has an inner surface, an outer surface opposite the inner surface, and a plurality of through-holes. When coupled with a light-transmissive conductive material, such as indium tin oxide (ITO), the substrate provides an electrical connection between a light-transmissive conductive layer (which can be used as a top electrode in an electro-optic display) and a contact point on the outer surface of the light-transmissive substrate. Thus, the light-transmissive substrate allows for simpler electrical connections for electro-optic displays, particularly for large-sized devices that can need to be cut or assembled in the field. Furthermore, the redundancy of having tens to hundreds of electrical contacts minimizes the likelihood that a device becomes inoperable due to a broken electrical connection.

Description

[0001] Related applications

[0002] This application claims priority to U.S. Provisional Patent Application No. 63 / 086,695, filed October 2, 2020. All patents and publications disclosed herein are incorporated herein by reference in their entirety. Technical Field

[0003] This invention relates to a front-plane laminate, a manufacturing process for the laminate, and an electro-optic display formed from the laminate. More specifically, in one aspect, the invention relates to a front-plane laminate having a substrate comprising a distributed portion within a continuous portion. The distributed portion comprises a conductive material that forms an electrical connection between a conductive layer of the front-plane laminate and a contact point on the outer surface of the substrate. Background Technology

[0004] The term "electro-optic," used in this document to refer to materials or displays, is used in its conventional meaning in the field of imaging. It refers to a material having a first display state and a second display state, where at least one optical property differs between the first and second display states, and the material is changed from its first display state to its second display state by applying an electric field. While the optical property is typically color perceptible to the human eye, it can be another optical property, such as light transmission, reflection, emission, or, in the case of displays used for machine reading, a pseudocolor in the sense of a change in reflectivity at electromagnetic wavelengths outside the visible light range.

[0005] Several types of electro-optic displays are known. One type of electro-optic display is the rotating bicolor component type, as described, for example, in U.S. Patent Nos. 5,808,783, 5,777,782, 5,760,761, 6,054,071, 6,055,091, 6,097,531, 6,128,124, 6,137,467, and 6,147,791 (although this type of display is often referred to as a "rotating bicolor sphere" display, the term "rotating bicolor component" is preferred as it is more accurate because in some of the patents mentioned above, the rotating component is not spherical). This display uses a number of small bodies (typically spherical or cylindrical) and internal dipoles, said bodies comprising two or more parts with different optical properties. These bodies are suspended within liquid-filled bubble chambers within a matrix, the bubble chambers being filled with liquid to allow the bodies to rotate freely. The appearance of the display is changed by applying an electric field to the display, thereby rotating the subject to various positions and changing which part of the subject is seen through the viewing surface.

[0006] Another type of electro-optic display uses electrochromic media, such as those in the form of nanochromic films, which include electrodes formed at least partially of semiconductor metal oxides and multiple dye molecules attached to the electrodes capable of reversible color changes; see, for example, O'Regan, B. et al., Nature 1991, 353, 737; and Wood, D., Information Display, 18(3), 24 (March 2002). See also Bach, U. et al., Adv. Mater., 2002, 14(11), 845. This type of nanochromic film is also described, for example, in U.S. Patent Nos. 6,301,038, 6,870,657, and 6,950,220. This type of medium is also typically bistable.

[0007] Another type of electro-optic display is the electrowetting display developed by Philips, described in Hayes, RA et al., "Video-Speed ​​Electronic Paper Based on Electrowetting", Nature, 425, 383-385 (2003). U.S. Patent No. 7,420,549 shows that such an electrowetting display can be fabricated as bistable. Other known electro-optic display materials include liquid crystal displays (LCDs), organic light-emitting diode displays (OLEDs), light-emitting diodes (LEDs), and micro / miniature LEDs.

[0008] For many years, electro-optic displays have been a subject of intensive research and development. One type of display is the particle-based electrophoretic display, in which multiple charged particles move through a fluid under the influence of an electric field. Compared to liquid crystal displays, electrophoretic displays can offer advantages such as good brightness and contrast, wide viewing angles, state-stability, and low power consumption.

[0009] Numerous patents and applications assigned to or in the name of MIT, Einkel Corporation, Einkel California, LLC, and related companies describe various techniques for electrophoresis and other electro-optic media for encapsulation and microcells. Encapsulated electrophoretic media comprise numerous small capsules, each capsule itself comprising an inner phase and a capsule wall surrounding the inner phase, wherein the inner phase contains electrophoretically movable particles in a fluid medium. Typically, the capsules themselves are held in a polymer binder to form a coherent layer located between two electrodes. In microcell electrophoretic displays, charged particles and fluid are not encapsulated within microcapsules but are retained within multiple cavities formed within a carrier medium (typically a polymer film). Techniques described in these patents and applications include:

[0010] (a) Electrophoretic particles, fluids, and fluid additives; see, for example, U.S. Patent Nos. 7,002,728 and 7,679,814;

[0011] (b) Encapsulation, adhesives, and encapsulation processes; see, for example, U.S. Patent Nos. 6,922,276 and 7,411,719;

[0012] (c) Microunit structures, wall materials, and methods of forming microunits; see, for example, U.S. Patent Nos. 7,072,095 and 9,279,906;

[0013] (d) Methods for filling and sealing microcells; see, for example, U.S. Patent Nos. 7,144,942 and 7,715,088;

[0014] (e) Thin films and subassemblies containing electro-optic media; see, for example, U.S. Patent Nos. 6,982,178 and 7,839,564;

[0015] (f) Backplanes, adhesive layers and other auxiliary layers in displays and methods thereof; see, for example, U.S. Patent Nos. 7,116,318 and 7,535,624;

[0016] (g) Color formation and color adjustment; see, for example, U.S. Patent Nos. 7,075,502 and 7,839,564;

[0017] (h) A method for driving a display; see, for example, U.S. Patent Nos. 7,012,600 and 7,453,445;

[0018] (i) Applications of displays; see, for example, U.S. Patent Nos. 7,312,784 and 8,009,348; and

[0019] (j) Non-electrophoretic displays, as described in U.S. Patent Nos. 6,241,921 and 2015 / 0277160; and applications of packaging and microcell technologies other than displays; see, for example, U.S. Patent Application Publication Nos. 2015 / 0005720 and 2016 / 0012710.

[0020] Many of the aforementioned patents and applications recognize that the walls surrounding discrete microcapsules in an encapsulated electrophoretic medium can be replaced by a continuous phase, thereby producing a so-called polymer dispersion electrophoretic display, wherein the electrophoretic medium comprises a plurality of discrete droplets of electrophoretic fluid and a continuous phase of polymeric material, and the discrete droplets of electrophoretic fluid within such a polymer dispersion electrophoretic display can be considered as capsules or microcapsules, even if no discrete capsule membrane is associated with each individual droplet; see, for example, the aforementioned U.S. Patent No. 6,866,760. Therefore, for the purposes of this application, such polymer dispersion electrophoretic media are considered a subclass of encapsulated electrophoretic media.

[0021] Encapsulated electrophoretic displays are generally unaffected by the clustering and sedimentation failure modes of conventional electrophoretic apparatus and offer more beneficial effects, such as the ability to print or coat displays on a variety of flexible and rigid substrates. (The term "printing" is used to include all forms of printing and coating, including but not limited to: pre-metering coatings such as patch die coating, slot or extrusion coating, slide or stack coating, curtain coating; roller coatings such as roller blade coating, forward and reverse roller coating; concave coating; dip coating; spray coating; meniscus coating; spin coating; brush coating; air knife coating; screen printing; electrostatic printing; thermal printing; inkjet printing; electrophoretic deposition (see U.S. Patent No. 7,339,715); and other similar techniques.) Therefore, the resulting displays can be flexible. Furthermore, because the display medium can be printed (using various methods), the display itself can be manufactured inexpensively. Other types of electro-optic media can also be used in embodiments of the invention.

[0022] Electro-optic displays typically comprise an electro-optic dielectric layer and at least two other layers disposed on opposite sides of the electro-optic dielectric, one of which is an electrode layer. In most such displays, both layers are electrode layers, and one or both electrode layers are patterned to define pixels of the display. For example, one electrode layer may be patterned as elongated row electrodes, while the other electrode layer may be patterned as elongated column electrodes extending perpendicularly to the row electrodes, with pixels defined by the intersections of the row and column electrodes. Alternatively, and more generally, one electrode layer has the form of a single continuous electrode, while the other electrode layer is patterned as a matrix of pixel electrodes, each pixel electrode defining one pixel of the display. In another type of electro-optic display intended for use with styluses, printheads, or similar movable electrodes separate from the display, only one of the layers adjacent to the electro-optic layer includes electrodes, and the layer on opposite sides of the electro-optic layer is typically a protective layer designed to prevent damage to the electro-optic layer by the movable electrodes.

[0023] The manufacture of three-layer electro-optic displays typically involves at least one lamination operation. For example, several patents and applications from MIT and Einkel described above describe a process for manufacturing an encapsulated electrophoretic display in which an encapsulated electrophoretic medium comprising a capsule in an adhesive is coated onto a light-transmitting conductive layer as the top electrode layer of the final display, and then applied to a light-transmitting substrate. The capsule / adhesive coating is then dried to form a coherent layer of electrophoretic medium firmly adhered to the conductive layer, providing an article of manufacture hereinafter referred to as a "front-plane laminate" or "FPL" for convenience.

[0024] Individually, a backplate comprising an array of pixel electrodes and a suitably arranged conductor for connecting the pixel electrodes to driving circuitry is fabricated. To form the final display, the FPL is laminated to the backplate using a laminating adhesive. (A very similar process can be used to fabricate an electrophoretic display that can be used with a stylus or similar movable electrodes by replacing the backplate with a simple protective layer, such as a plastic film, on which a stylus or other movable electrode can slide). In an exemplary form of this process, the backplate itself is flexible and is fabricated by printing pixel electrodes and conductors onto a plastic film or other flexible substrate. A common lamination technique for mass-producing displays using this process is roll lamination using a laminating adhesive. Similar manufacturing techniques can be used for other types of electro-optic displays. For example, microcell electrophoretic media or rotating dual-color component media can be laminated to the backplate in substantially the same manner as encapsulated electrophoretic media.

[0025] When using a front-plane laminate in a display, an electrical connection is required between the voltage source and a transparent conductive layer through which the electro-optic medium is visible. This transparent conductive layer is sometimes referred to as the "top-plane" electrode. In some cases, the connection is established directly via wires or conductive traces coupled directly from the power supply or controller to the conductive layer. More typically, voltage is transmitted along the backplane using manufacturing traces leading to conductive pads, and the necessary electrical connection is achieved by providing at least one "connection area" in the display where the top conductive layer is accessible and not in contact with the electro-optic medium.

[0026] The connection areas can be provided in two different ways. First, the formation of the electro-optic dielectric layer can be controlled to leave uncoated areas (“grooves”) where no electro-optic dielectric exists, and portions of these uncoated areas can later be used as connection areas. Alternatively, the entire surface of the laminate can be covered with an electro-optic dielectric, which can then be removed from the connection areas in any convenient manner, such as by cutting, mechanical abrasion, or chemical degradation of the electro-optic layer. A conductive material, such as a conductive filler, like conductive silver paste or an adhesive, is then inserted to contact the connection areas and form an electrical connection between the top electrode layer and the top planar connection (TPC) in the backplane to complete the circuit.

[0027] In some cases, after removing the electro-optic dielectric from the connection area, the laminate may need to be cleaned to remove any electro-optic dielectric residue; for example, if the electro-optic dielectric is an encapsulated electrophoretic material, it is desirable to remove any remaining internal phase after capsule rupture during the removal of the electrophoretic material from the connection area. Since the top conductive layer is typically made of a relatively brittle material such as indium tin oxide (ITO), forming the connection area and inserting the conductive filler is a delicate process, and the solvent used to clean its peripheral walls should be chosen to dissolve the electro-optic layer without damaging the top conductive layer. Furthermore, the amount of conductive filler should be sufficient to complete the circuitry but not in an amount that could leak, creep, or migrate, or otherwise easily cause a short circuit. Importantly, when the FPL is incorporated into a hermetically sealed display (also known as a module), a portion of the FPL must be cut and cleaned for the top-plane connection before lamination to the backplane. This requires very precise alignment between the cut piece and the backplane. Keeping all components clean and aligned is particularly challenging for larger displays, or when prototyping or manufacturing custom displays without alignment fixtures. Alignment fixtures are impractical for disposable displays, and may even be infeasible for some irregularly shaped displays. If parts of the FPL are fabricated after lamination, the cleaning process may damage the top and / or back conductive layers.

[0028] For the reasons mentioned above, the conventional process for forming the top plate connection can be complex, time-consuming, and prone to damaging the top electrode layer and other parts of the final assembly if not performed properly. Therefore, there is a need to improve the mass production technology associated with the manufacturing of the top plate connection. Summary of the Invention

[0029] These and other aspects of the invention will become apparent from the following description.

[0030] In a first aspect, this document provides an article of manufacture comprising, in sequence: a light-transmitting substrate having an inner surface and an outer surface opposite to the inner surface; a light-transmitting conductive layer; an electro-optic dielectric layer; an adhesive layer; and a release sheet in contact with the adhesive layer, wherein the electro-optic dielectric layer is disposed between the light-transmitting conductive layer and the adhesive layer. The light-transmitting substrate includes: a continuous portion; and a plurality of openings within the continuous portion, wherein the openings comprise a conductive material that forms an electrical connection between contact points on the light-transmitting conductive layer and the outer surface of the light-transmitting substrate.

[0031] In a second aspect, a laminated electro-optic display is provided, comprising, in sequence: a front planar light-transmitting substrate having an inner surface and an outer surface opposite to the inner surface; a light-transmitting conductive layer; an electro-optic dielectric layer electrically in contact with the conductive layer; and a back plate including a conductor; wherein: the front planar light-transmitting substrate includes: a continuous portion and a plurality of openings within the continuous portion, wherein the openings include a conductive material, the conductive material forming an electrical connection between contact points of the light-transmitting conductive layer and the outer surface of the front planar light-transmitting substrate.

[0032] In a third aspect, a light-transmitting and conductive material is provided, comprising: a light-transmitting substrate having a first surface, a second surface opposite to the first surface, and a plurality of through-holes; wherein a conductive material selected from alumina, zinc oxide, indium oxide, indium tin oxide, and poly(3,4-ethylenedioxythiophene) is in contact with the first surface of the substrate, and the conductive material forms a light-transmitting and conductive surface adjacent to the first surface of the light-transmitting substrate, while also providing electrical connections to contact points on the second surface of the light-transmitting substrate through the plurality of through-holes, wherein the through-holes have an average diameter of at least 0.1 micrometers to at most 100 micrometers. In one embodiment, the light-transmitting substrate is a polymer material. In one embodiment, the through-holes have an average diameter of at least 0.5 micrometers to at most 10 micrometers. In one embodiment, the through-holes have a shape selected from the group consisting of circles, lines, and ellipses. In one embodiment, the contact points are located on a portion of the outer surface of the light-transmitting substrate, wherein the portion has an average density of at least 10 contact points per square centimeter to at most 1000 contact points per square centimeter.

[0033] In a fourth aspect, a method for manufacturing a laminated electro-optic display is provided, the method comprising: laminating a front planar laminate to a back plate, wherein the front planar laminate sequentially comprises: a front planar light-transmitting substrate having an inner surface and an outer surface opposite to the inner surface; a light-transmitting conductive layer; an electro-optic dielectric layer electrically in contact with the light-transmitting conductive layer; and an adhesive layer, wherein the front planar light-transmitting substrate includes: a continuous portion and a plurality of openings within the continuous portion, wherein the openings comprise a conductive material, the conductive material forming an electrical connection between contact points on the light-transmitting conductive layer and the outer surface of the front planar light-transmitting substrate; and the back plate includes a top plane connection; and at least one of the contact points on the outer surface of the front planar light-transmitting substrate forms an electrical connection with the top plane connection.

[0034] In a fifth aspect, a method for manufacturing a laminated electro-optic display is provided, the method comprising: laminating a front planar laminate to a back plate, wherein the front planar laminate sequentially comprises: a front planar light-transmitting substrate having an inner surface and an outer surface opposite to the inner surface; a light-transmitting conductive layer; an electro-optic dielectric layer electrically in contact with the light-transmitting conductive layer; and an adhesive layer, wherein the front planar light-transmitting substrate includes a continuous portion and a plurality of openings within the continuous portion, wherein the openings comprise a conductive material, the conductive material forming an electrical connection between contact points on the light-transmitting conductive layer and the outer surface of the front planar light-transmitting substrate; and the back plate includes a top plane connection; and at least one of the contact points on the outer surface of the front planar light-transmitting substrate forms an electrical connection with the top plane connection. Attached Figure Description

[0035] The accompanying drawings illustrate one or more embodiments according to the present concept, and are by way of example only and not as a limitation. In the drawings, the same reference numerals denote the same or similar elements.

[0036] Figure 1 This is a schematic cross-sectional view of a traditional front-plane laminate (FPL).

[0037] Figure 2 This is a schematic perspective cross-sectional view of the front planar laminate including the light-transmitting substrate of the present invention.

[0038] Figures 3A-3C This is a schematic top view of a front-plane transparent substrate with contact points of different geometric shapes according to an embodiment of the present invention.

[0039] Figures 4A-4C This is a schematic top view of a front-plane light-transmitting substrate having elongated contact points formed in a repeating pattern according to an embodiment of the present invention.

[0040] Figure 5 This is a perspective cross-sectional view of a laminated electro-optic display according to an embodiment of the present invention.

[0041] Figure 6 Is it through Figure 5 A perspective cross-sectional view of a laminated electro-optical display, in which an electrical connection is established between the front-plane laminated contact point and the back-plane conductor.

[0042] Figure 7 This is a schematic top view of a display device made of strips, which include the invention described herein and are interwoven with fabric portions to create a flexible structure that can be altered as needed to increase or decrease the amount and color of light reflected or transmitted through the structure. Detailed Implementation

[0043] In the detailed description below, many specific details are illustrated by way of examples in order to provide a thorough understanding of the teachings. However, it will be apparent to those skilled in the art that these teachings can be practiced without these details.

[0044] This invention includes a light-transmitting substrate having an inner surface, an outer surface opposite the inner surface, and a plurality of through-holes. When coupled to a light-transmitting conductive material such as indium tin oxide (ITO), the substrate provides electrical connections between a light-transmitting conductive layer (which can be used as a top electrode in an electro-optic display) and contact points on the outer surface of the light-transmitting substrate. Therefore, the light-transmitting substrate allows for simpler electrical connections for electro-optic displays, particularly for large-sized devices that may require on-site cutting or assembly. Furthermore, the redundancy of tens to hundreds of electrical contacts minimizes the possibility of the device becoming inoperable due to a disconnection.

[0045] As previously described, this application provides, in one aspect, a novel article (hereinafter referred to as a "front-plane laminate" or "FPL") that simplifies the formation of an electrical connection between a top light-transmitting conductive layer and a voltage source by forming an electrical connection between the top light-transmitting conductive layer and a contact point on the outer surface of a front-plane light-transmitting substrate. The electrical connection can be made within micro-holes or vias, and a simple clamping can be applied externally (e.g., at the outer edge) to establish a partial or complete electrical connection with the outer surface of the front-plane light-transmitting substrate. Alternatively, conductive pads or conductive tapes can be used to establish the connection with the front-plane light-transmitting substrate. Alternatively, a front-plane light-transmitting substrate with micro-holes can also provide better compliance with complex curves. For example, micro-holes or strips can be etched in the surface to allow deformation without disrupting the connection with the light-transmitting conductive layer. This invention is particularly suitable for simplifying complex structures requiring multiple connections to the light-transmitting conductive layer.

[0046] Now refer in detail to the examples shown in the accompanying drawings and discussed below. The use of terms such as “top,” “bottom,” “above,” and “below” is merely a convention, as the relative positions of two or more layers can be switched by reorienting the articles in different directions.

[0047] Front flat laminate

[0048] Before proceeding further, it is desirable to provide an illustrative description of conventional front-plane laminates (“FPL”), such as Figure 1The cross-sectional view is schematically shown. FPL 100 is similar to the device described, for example, in U.S. Patent No. 10,503,041, which is incorporated herein by reference. FPL 100 may include, in sequence: a front planar light-transmitting substrate 102; a light-transmitting conductive layer 104 in contact with the inner surface of the front planar light-transmitting substrate; an electro-optic dielectric layer 106 in contact with the conductive layer; an adhesive layer 108; and a release sheet 110.

[0049] In many applications, the front-plane light-transmitting substrate 102 comprises polyethylene terephthalate (PET) and the light-transmitting conductive layer 104 comprises indium tin oxide (ITO). This material is commercially available in bulk rolls from sources such as Saint-Gobain. The light-transmitting conductive layer 104 is applied to the light-transmitting substrate 102, and the light-transmitting substrate 102 is typically flexible in the sense that the substrate can be manually wound onto a 10-inch (254 mm) diameter roller without, for example, permanent deformation.

[0050] The term "transmittance" is used throughout the specification and claims to indicate that a layer so specified transmits sufficient light to allow an observer to view through the layer to observe changes in the display state of the electro-optic medium, typically through the conductive layer and the adjacent substrate; in the case of changes in reflectivity of the electro-optic medium at invisible wavelengths, the term "transmittance" should of course be interpreted as transmission at the relevant invisible wavelength. Substrate 102 may be made of glass or a polymer film such as polyethylene terephthalate (PET) and may have a thickness ranging from about 20 μm to about 650 μm, more typically from about 50 μm to about 250 μm. The conductive layer is typically a thin layer of so-called "transparent conductive oxides" such as aluminum oxide, zinc oxide, indium zinc oxide, or indium tin oxide (ITO), or the conductive layer may comprise a conductive polymer such as poly(3,4-ethylenedioxythiophene) (PEDOT). The design may also include hybrid materials, such as a combination of conductive polymers and conductive oxides, or the design may include diluted amounts of conductive fillers, such as silver whiskers or flakes, or rare materials such as nanotubes and graphene. In some embodiments, the substrate 102 may be a rigid, light-transmitting material, such as glass or transparent polycarbonate or acrylic.

[0051] Typically, a coating of an electro-optic medium that can be switched between optical states 106 is applied to the conductive layer 104, such that the electro-optic medium 106 is adjacent to the conductive layer 104. The electro-optic medium typically has an electrophoretic material comprising multiple charged particles disposed in a fluid and capable of moving through the fluid under the influence of an electric field. The electrophoretic material can be selected such that the front-plane laminate can interchangeably and reversibly achieve different states when an appropriate electric field is applied; for example, the electrophoretic medium can switch between transparent and opaque, or color 1 and color 2, or transparent and color 1 and color 2.

[0052] In an exemplary embodiment, the electro-optic medium may be in the form of a dual-particle encapsulated medium with opposite charges. Such an encapsulated medium comprises a plurality of small capsules, each capsule comprising an inner phase and a capsule wall surrounding the inner phase, the inner phase containing electrophoretically moving particles suspended in a liquid suspension medium. Typically, the capsules themselves are held within a polymer binder to form a coherent layer. When the coherent layer is located between two electrodes, the optical state can be reversed with the presence of a suitable electric field. The suspension medium may comprise a hydrocarbon-based liquid in which negatively charged white particles and positively charged black particles are suspended. In such an embodiment, when an electric field is applied to the electro-optic medium, the white particles can move to the positive electrode and the black particles can move to the negative electrode, for example, causing the electro-optic medium 106 to appear white or black to an observer viewing the display through the substrate 102, depending on whether the conductive layer 104 is positive or negative relative to the backplane at any point within the final display. The electro-optic medium 106 may alternatively comprise a plurality of colored particles in addition to black and / or white particles, each color having its own charge polarity and intensity.

[0053] A laminating adhesive layer 108 can be coated onto the electro-optic dielectric layer 106, and a release sheet 110 can be applied onto the adhesive layer 108. The release sheet can be of any known type, provided it does not contain materials that could adversely affect the performance of the electro-optic dielectric, and those skilled in the art will recognize many suitable types of release sheets. Common release sheets include substrates such as paper or plastic films, for example, PET films with a thickness of approximately 150 μm to approximately 200 μm coated with a low surface energy material such as silicone. In some cases, the release sheet is metallized to allow a potential to be applied to the electro-optic dielectric, thereby enabling the evaluation of functionality during the assembly of downstream products.

[0054] Now refer to Figure 2 A novel front-plane laminate (designated 100A) according to one aspect of the invention is shown. FPL and Figure 1The laminate 100 shown is substantially the same, except that it has a front-plane light-transmitting substrate 102 with an inner surface 112 and an outer surface 114 opposite to the inner surface. It is characterized by a composite structure comprising a continuous portion 102a and a plurality of openings 102b distributed within the continuous portion 102a. The openings 102b include conductive material 115 forming an electrical connection between the conductive layer 104 and one or more contact points 116 on the outer surface 114. Optionally, the conductive layer 104 may be divided into two or more portions, each contacting a subset (not shown) of the contact points, thereby creating an architecture in which a short circuit in one portion will not cause failure in other portions. The electrical connection may be applied locally or over the entire outer surface, and a protective layer (not shown), such as a transparent acrylic polymer or silicone coating, may be added to seal some or all of the contact points and provide a moisture barrier while preventing unwanted short circuits after assembly.

[0055] In an exemplary embodiment, the continuous portion 102a may be made of glass or a polymer film such as polyethylene terephthalate (PET), which is subjected to etching, cutting, laser ablation, or any suitable perforation technique to leave an opening. Alternatively, the continuous portion 102a may be microindented to create vias or valleys that can be filled during a sputtering process by which a conductive layer material, such as ITO, is added. Alternatively, the PET film may be softened by heating, stretched on a mold, and the pores formed using a high-pressure gas jet. The openings can then be filled with a conductive material to form contact points 116. The openings can be configured in various shapes, sizes, and densities to suit the application at hand. Regardless of shape, the individual point size and average point size can be defined based on a given point dimension. Unless otherwise specified or apparent from the context, the term “dimension” refers to the length, width, or diameter of the contact point along the surface of the layer. Generally, “length” refers to the extension in the longitudinal direction, and “width” refers to the extension in the width direction. When used for contact points, the term "diameter" is intended to identify the longest straight line segment between the two tips at a point along the outer surface of the front-plane transparent substrate. In some non-exclusive embodiments, the geometry of the contact points 116 is such that their average diameter falls within the range of about 0.1 μm to about 100 μm. In other embodiments, the average contact point diameter falls within the range of about 0.5 μm to about 10 μm.

[0056] exist Figure 3A The schematic top view shows a front-plane transparent substrate 102 with a circular geometry contact point 116, which can be fabricated by micro-etching a polymer thin film substrate to form a rounded corner opening. Exemplary average indentation diameter ranges from about 10 μm to about 100 μm, from about 10 μm to about 75 μm, and from about 10 μm to about 50 μm. Figure 3BA substrate has been micro-etched to create strip openings with an average width of 100 μm or less. Exemplary average strip width ranges include about 1 μm to about 100 μm, about 2 μm to about 75 μm, and about 5 μm to about 50 μm. Figure 3C The image schematically illustrates another substrate that has been micro-etched to form an elliptical opening with an average minor axis length equal to or less than about 100 μm. Exemplary average minor axis length ranges from about 1 μm to about 100 μm, from about 5 μm to about 75 μm, and from about 10 μm to about 50 μm.

[0057] Various contact point shapes, surface densities, and spatial arrangements can be specifically designed to enhance the ability of front-plane laminates to adopt complex and curved shapes without compromising electrical connections, while maintaining the structural integrity of the electro-optic medium. In some embodiments, conductive material can be deposited in the openings after the continuous phase has been perforated and shaped to conform to the desired geometry and contact point density. One or more portions of a front-plane transparent substrate can be fabricated in this way to create customized architectures to serve different types of applications. Figure 4A As shown in the schematic top plan view, elongated contact points 116 can be formed into a repeating pattern at the edge of the front-plane transparent substrate 102. Figure 4B In the middle, the pattern repeats in the center of the front-plane light-transmitting substrate, while Figure 4C The patterns have different sizes and relative orientations. This method enables the manufacture of front-plane laminates with geometries and contact point patterns specifically designed to suit any type of application. Contact points 116 can be formed and positioned in specific portions of the front-plane light-transmitting substrate 102 at a density range suitable for the application at hand. In one representative embodiment, a portion of the front-plane light-transmitting substrate 102 includes contact points 116 with a density ranging from about 10 contact points per square centimeter to about 1000 contact points per square centimeter. In another embodiment, a portion of the front-plane light-transmitting substrate 102 includes contact points 116 with a density ranging from about 50 contact points per square centimeter to about 500 contact points per square centimeter. Embodiments with densities ranging from about 50 contact points per square centimeter to about 250 contact points per square centimeter are also contemplated.

[0058] Manufacturing front flat laminate

[0059] As described above, contact points 116 can be formed by introducing conductive material 115 into openings 102b present in a continuous portion 102a of the front-plane light-transmitting substrate 102. Also as described above, openings 102b can be indentations formed by removing a portion of a polymer layer. In one embodiment, a film of a flexible light-transmitting polymer (e.g., PET) can be indented, drilled, ablated, etc., to form multiple openings. The flexible light-transmitting polymer can then be coated with a light-transmitting conductive material (e.g., ITO), for example, by sputtering. Since the light-transmitting material is coated on the inner surface, the openings 102b are also filled with the light-transmitting conductive material, thereby providing electrical connection to the outer surface 114 of the front-plane light-transmitting substrate (PET film). Because the openings 102b are small and because both the substrate 102 and the conductive material 115 are light-transmitting, the conductive material 115 is not visually distracting. In another embodiment, a flowable conductive material precursor, such as a solution or slurry, is introduced into the openings and then cured to create electrical connections and contact points. Depending on the relatively small opening diameter and the viscosity of the precursor, this process may prove difficult to perform in practice. To overcome these difficulties, suction can be applied to improve precursor flow and / or a surfactant can be added to the precursor to reduce the surface tension of the opening surface. In another non-exclusive embodiment, the conductive material 115 and / or its precursor may be magnetizable, in which case this can facilitate filling the opening with material. In an exemplary embodiment, the same microfabrication methods used for manufacturing microvias in high-density interconnect (HDI) multilayer printed circuit boards (PCBs) can be used, for example, by adding layers in successive time, such as using copper or other conductive materials (e.g., carbon or carbon nanotubes) in sequential build-up (SBU) manufacturing techniques. In another embodiment, the conductive material can be applied by electroplating techniques.

[0060] In a broader sense, the distributed portions do not necessarily need to be formed by introducing conductive filler within the openings of the continuous portions. In some embodiments, the front-plane light-transmitting substrate can be manufactured by combining insulating and conductive materials in an anisotropic manner, thereby creating electrical connections and corresponding conductive points distributed within the continuous portions. In a representative example, the front-plane light-transmitting substrate can be manufactured by interlacing PET fibers with conductive yarns, for example, as PET coated with a conductive material, such as a metal or a conductive polymer such as polyaniline (PANI). Throughout the manufacturing process, the conductive yarns are selectively included in areas of the front-plane light-transmitting substrate intended to form electrical connections and contact points.

[0061] All of the methods described above assume that the contact points are formed before the front-plane transparent substrate is assembled with the other parts of the front-plane laminate. However, in some embodiments, conductive material can be introduced into the opening after the FPL is assembled, provided that the conductive material precursor does not flow through the electro-optic medium and short-circuit it.

[0062] Optoelectronic Display

[0063] In one application, a front plane laminate is laminated to a backplate to form an electro-optical display. Backplates are mainly divided into three categories: active matrix backplates, passive matrix backplates, and direct drive backplates.

[0064] For a typical active matrix backplate, a thin film transistor (TFT) array (not shown) is formed on the surface of the backplate substrate 202, and each transistor acts as a switch for a pixel electrode (212a, 212c). The TFTs are addressed by a set of narrow multiplexing electrodes (gate lines and source lines). A passive matrix backplate uses a simple grid to supply charge to specific pixels on the display. The grid is formed on a top substrate and a bottom substrate. One substrate forms "columns" and the other substrate forms "rows". In a passive matrix, the columns or rows are made of a transparent conductive material, which is typically indium tin oxide (ITO). The rows or columns are connected to an integrated circuit that controls when charge is applied to a particular column or row. In a direct drive backplate, the bottom substrate may include an electrical connector located on an edge of the substrate, from which a plurality of conductors extend to form contact with a plurality of segments of a segmented conductive layer, such that each segment is electrically connected to a corresponding conductor. There is no limitation on the type of backplate that can be used in various embodiments of the present invention, as long as a front-plane connection through contact points disposed on the outer surface of the front-plane light-transmitting substrate is formed.

[0065] Turning now to Figure 5 , assembly of an electro-optical display using FPL 100 and a backplate such as backplate 200 can be achieved by the following process: removing the release sheet 110 and bringing the adhesive layer 108 into contact with the backplate 200 under conditions effective to adhere the adhesive layer to the backplate, thereby fixing the adhesive layer, the electro-optical medium layer 106 and the light-transmitting conductive layer 104 to the backplate. The FPL 100 may be cut to a size larger than the final display size, and may even be a continuous sheet as in a roll-to-roll process. This allows for coarse tolerances in the alignment of the FPL 100 and the backplate 200, which is particularly useful for large displays. After lamination (not shown), the display may be cut to its final size, possibly using alignment marks or pins on the backplate to allow precise alignment of the cut with the backplate.

[0066] The lamination of FPL 100 to backplane 200 can advantageously be performed by vacuum lamination. Vacuum lamination effectively removes air between the two laminated materials, thus avoiding unwanted air bubbles in the final display; such bubbles can introduce undesirable artifacts into the image produced on the display. However, vacuum laminating the two parts of the electro-optic display in this manner can place stringent requirements on the lamination adhesive used, especially in the case of displays using encapsulated electrophoretic media. The lamination adhesive 108 should have sufficient adhesive strength to bond the electro-optic layer to the backplane, and in the case of encapsulated electrophoretic media, the adhesive 108 should also have sufficient adhesive strength to mechanically hold the capsule together. The adhesive 108 is preferably chemically compatible with all other materials in the display. If the electro-optic display is flexible, the adhesive 108 should have sufficient flexibility to prevent defects from being introduced into the display when it is bent. The lamination adhesive 108 should have sufficient flow properties at the lamination temperature to ensure high-quality lamination. Furthermore, the lamination temperature is preferably as low as possible. An example of a useful laminating adhesive that can be incorporated into the various embodiments of the present invention is an aqueous polyurethane dispersion known as the “TMXDI / PPO” dispersion, as described in U.S. Patent No. 7,342,068, which is incorporated herein by reference in its entirety.

[0067] Top plane connection 204 can be electrically connected to all or a specific subset of conductive points 116. Typically, top plane connection 204 from the backplane is integrated into the backplane 200, but for clarity, it is... Figure 5 and Figure 6 In this context, the terms are represented as independent items. In a representative embodiment, such as... Figure 6 As schematically shown, this connection can be achieved using wires or traces (304 / 306) or a combination thereof. Since each conductive point 116 is connected to the light-transmitting conductive layer 104, it is not necessary to connect each conductive point 116 to the top plane connection 204. However, it is common to connect more than one conductive point. In some cases, conductive traces are applied across the entire outer surface, such as... Figure 6 As illustrated, this is achieved by linking a subset of contact points to conductor 306 and backplane connection 204 via conductive transparent wiring 304. In such embodiments, a protective layer such as a transparent coating of acrylic or silicone can be used to isolate the connection points and prevent unwanted short circuits (not shown) after assembly. In alternative embodiments, conductive contact pads coupled to wire 304 can be fixed to the outer surface, for example, using conductive adhesive. In other embodiments, the connection between top plane connection 204 and conductive point 116 can be made using conductive clamps such as alligator clips.

[0068] Flexible, variable color, and translucent coverings

[0069] In another application, the front planar laminate can be cut into sealed portions and then interwoven with portions of conventional materials (e.g., fabrics, polymers). Alternatively, strips of one or more types of front planar laminate 100 can be interwoven with fabric strips 700 to form a woven structure of fabric 700 and front planar laminate 100. Figure 7 The exemplary weave schematically illustrates an FPL strip 100 interwoven with fabric portion 700 to create a semi-transparent flexible weave, which can be altered as needed to increase or decrease the amount and color of light reflected or transmitted through the weave. Alternatively, both directions of the weave can be achieved using strips of the front planar laminate 100. Variable color and transmissive coverings with this type of architecture are described in U.S. Patent No. 11,086,186, which is incorporated herein by reference in its entirety. However, as noted above, in order to make electrical contact with the conductive layer within a conventional laminate, at least one “connection area” is typically required, where the conductive layer is unaffected by the electro-optic medium. Therefore, each FPL strip in the weave requires its own separate connection area, resulting in a structurally complex structure that is relatively expensive and labor-intensive to manufacture.

[0070] exist Figure 7 In this structure, forming electrical contacts on the FPL strip 100 made of the novel laminate disclosed in this application is greatly simplified. Contact points 116 on the upper surface of the light-transmitting substrate 102 can be easily connected to the conductive layer of a given strip by applying conductive jigs or laying wires or traces. The mixing of electro-optic materials and conventional materials in the structure does not require... Figure 7 The ratio shown is 1:1. For example, the surface area of ​​the electro-optic material included in the variable transmission structure can be 10 times larger than that of the conventional material. Alternatively, the surface area of ​​the conventional material included in the variable transmission structure can be 10 times larger than that of the electro-optic material. Of course, intermediate ratios are also possible, such as 5:1, 3:1, 2:1, 1:1, 1:2, 1:3, 1:5, etc. In other embodiments, the variable transmission structure may include two different types of interwoven electro-optic materials, similar to... Figure 7 Furthermore, woven materials incorporating three or more electro-optic materials are also envisioned. In one example, FPL strips containing bistable, reflective, or variable-transmittance materials can be woven together with conventional fabrics. In another embodiment, variable-transmittance strips can be woven together to form a flexible fabric that can switch between a light-transmitting state and a colored state.

[0071] While preferred embodiments of the invention have been shown and described herein, it should be understood that such embodiments are provided by way of example only. Many variations, alterations, and substitutions will occur to those skilled in the art without departing from the spirit of the invention. Therefore, the appended claims are intended to cover all such variations falling within the spirit and scope of the invention. All contents of the foregoing patents and applications are incorporated herein by reference in their entirety. In the event of any inconsistency between the contents of this application and any patents and applications incorporated herein by reference, the contents of this application shall prevail to the extent necessary to resolve such inconsistencies.

Claims

1. An article comprising, in order: A light-transmitting substrate having an inner surface and an outer surface opposite to the inner surface; Transparent conductive layer; Electro-optic dielectric layer; Adhesive layer; as well as A release sheet in contact with the adhesive layer, wherein the electro-optic dielectric layer is disposed between the light-transmitting conductive layer and the adhesive layer. The light-transmitting substrate includes: Continuous parts; and The plurality of openings within the continuous portion, wherein the openings comprise a conductive material formed of the same material as the light-transmitting conductive layer, thereby providing an electrical connection between the contact points of the light-transmitting conductive layer and the outer surface of the light-transmitting substrate.

2. The article of claim 1, wherein, The continuous portion of the light-transmitting substrate includes a polymer material with micro-indentations.

3. The article of claim 1, wherein, The light-transmitting conductive layer comprises a material selected from the group consisting of tin alumina, indium tin oxide, poly(3,4-ethylenedioxythiophene) and combinations thereof.

4. The article of claim 1, wherein, The electro-optic medium is an encapsulated electrophoretic medium.

5. The article of claim 1 further includes a protective layer located on the outer surface of the light-transmitting substrate.

6. The article of claim 1, wherein, The contact point has an average diameter of at least 0.1 micrometers to at most 100 micrometers.

7. The article of claim 1, wherein, The contact point has an average diameter of at least 0.5 micrometers to at most 10 micrometers.

8. The article of claim 1, wherein, The contact points are located on a portion of the outer surface of the light-transmitting substrate, wherein the portion has an average density of at least 10 contact points per square centimeter to at most 1000 contact points per square centimeter.

9. A laminated electro-optic display, comprising, in sequence: A front-plane light-transmitting substrate having an inner surface and an outer surface opposite to the inner surface; Transparent conductive layer; An electro-optic dielectric layer that is in electrical contact with the conductive layer; as well as Including the backplate of the conductor; in: The front planar light-transmitting substrate includes a continuous portion and a plurality of openings within the continuous portion, wherein the openings include a conductive material formed of the same material as the light-transmitting conductive layer, thereby providing an electrical connection between the contact points of the light-transmitting conductive layer and the outer surface of the front planar light-transmitting substrate.

10. The laminated electro-optic display according to claim 9, wherein, The continuous portion comprises a polymer material with microindentations.

11. The laminated electro-optic display according to claim 9, wherein, The electro-optic medium is an encapsulated electrophoretic medium.

12. The laminated electro-optic display according to claim 9 further includes a protective layer located on the outer surface of the front planar transparent substrate.

13. The laminated electro-optic display according to claim 9, wherein, The contact point has an average diameter of at least 0.1 micrometers to at most 100 micrometers.

14. The laminated electro-optic display according to claim 9, wherein, The contact point has an average diameter of at least 0.5 micrometers to at most 10 micrometers.

15. The laminated electro-optic display according to claim 9, wherein, The contact points are located on a portion of the outer surface of the front planar light-transmitting substrate, wherein the portion has an average density of at least 10 contact points per square centimeter to at most 1000 contact points per square centimeter.

16. A light-transmitting and conductive material, comprising: A light-transmitting substrate having a first surface, a second surface opposite to the first surface, and a plurality of through holes; as well as A conductive material, selected from alumina, zinc oxide, indium oxide, indium tin oxide, and poly(3,4-ethylenedioxythiophene), contacts the first surface of the substrate and fills the plurality of through holes. The conductive material forms a light-transmitting and conductive surface adjacent to the first surface of the light-transmitting substrate, and provides electrical connection to contact points on the second surface of the light-transmitting substrate through the plurality of through holes. The through-hole has an average diameter of at least 0.1 micrometers to at most 100 micrometers.

17. The light-transmitting and conductive material according to claim 16, wherein, The light-transmitting substrate is made of polymer material.

18. The light-transmitting and conductive material according to claim 16, wherein, The via has an average diameter of at least 0.5 micrometers to at most 10 micrometers.

19. The light-transmitting and conductive material according to claim 16, wherein, The through hole has a shape selected from a group consisting of circles, lines, and ellipses.

20. The light-transmitting and conductive material according to claim 16, wherein, The contact points are located on a portion of the outer surface of the light-transmitting substrate, wherein the portion has an average density of at least 10 contact points per square centimeter to at most 1000 contact points per square centimeter.

Images