Low voltage electrostatic extrusion device

Abstract

At least some embodiments of the present disclosure relate to an electrostatic sheet pressing device, the electrostatic sheet pressing device comprising: a first sheet having a first conductive layer; a first dielectric layer, the first dielectric layer being arranged adjacent to the first conductive layer; and a second sheet, the second sheet comprising a second conductive layer and being arranged close to the first dielectric layer. The first dielectric layer is arranged between the first conductive layer and the second conductive layer. The first sheet and the second sheet are inextensible and flexible, wherein the first sheet and the second sheet are able to slide relative to each other in a first state. In a second state when a voltage is applied between the first conductive layer and the second conductive layer, the first sheet and the second sheet are pressed against each other. In some embodiments, the applied voltage is less than or equal to the breakdown voltage of air at a certain distance between the first conductive layer and the second conductive layer.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of U.S. Application No. 62 / 691,446, filed on June 28, 2018, the disclosure of which is incorporated by reference in its entirety. Technical Field

[0003] The present disclosure relates to compression devices that can be used to resist motion. Summary of the invention

[0004] At least some embodiments of the present disclosure are directed to an electrostatic sheet pressing device, the electrostatic sheet pressing device comprising: a first sheet having a first conductive layer; a first dielectric layer, the first dielectric layer being disposed adjacent to the first conductive layer; a second sheet, the second sheet comprising a second conductive layer and being disposed proximate to the first dielectric layer. The first dielectric layer is disposed between the first conductive layer and the second conductive layer. The first dielectric layer has a thickness of less than or equal to 10 microns. The first sheet and the second sheet are inextensible and flexible, wherein the first sheet and the second sheet are capable of sliding relative to each other in a first state. In a second state when a voltage is applied between the first conductive layer and the second conductive layer, the first sheet and the second sheet are pressed against each other. The applied voltage is less than or equal to a breakdown voltage of air at a distance between the first conductive layer and the second conductive layer.

[0005] At least some embodiments of the present disclosure are directed to an electrostatic sheet pressing device, the electrostatic sheet pressing device comprising: a first group of sheets, each of which includes a first conductive layer; a second group of sheets, each of which includes a second conductive layer; a group of dielectric layers; a first connector, the first connector conductively connected to at least a portion of the first conductive layer of the first group of sheets; and a second connector, the second connector conductively connected to at least a portion of the second conductive layer of the second group of sheets. The first group of sheets and the second group of sheets are interdigitated. Each of the adjacent pairs of the first group of sheets and the second group of sheets has one dielectric layer of the group of dielectric layers disposed therebetween. Each of the group of dielectric layers has a thickness of less than or equal to 10 microns. The first group of sheets and the second group of sheets are capable of sliding relative to each other in a first state. In a second state when a voltage is applied between the first connector and the second connector, the first group of sheets and the second group of sheets are pressed against each other. The applied voltage is less than or equal to a breakdown voltage of air at a distance between adjacent conductive layers of one sheet in the first set of sheets and one sheet in the second set of sheets. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] The accompanying drawings are incorporated into and constitute a part of this specification and together with the description, explain the advantages and principles of the present invention.

[0007] Figures 1A to 1F Several examples of electrostatic extrusion devices are shown;

[0008] FIG. 2A to FIG. 2B An example of an extruded sheet is shown;

[0009] Figure 3A and Figure 3B Some examples of arrangements of extruded sheets in an extrusion device are shown;

[0010] 4A to 4F Some examples of extruded sheets with patterns and features are shown;

[0011] Figure 4G An example of an actuating element is shown;

[0012] Figure 5A An example of a flexible device having a squeezing device is shown;

[0013] Figure 5B An example of a flexible display with an extrusion device is shown;

[0014] Figure 6 A flow chart showing the assembly of an electrostatic extrusion device is shown;

[0015] Fig. 7A and Figure 7B depicts some examples of actuation components; and

[0016] Figure 8 Illustration of a laboratory prototype of the extrusion device.

[0017] In the accompanying drawings, like reference numerals indicate like elements. Although the above drawings, which may not be drawn to scale, illustrate various embodiments of the present disclosure, other embodiments may also be envisioned, as indicated in the detailed description. In all cases, the present disclosure describes the presently disclosed disclosure in the form of representations of exemplary embodiments rather than by express limitation. It should be understood that those skilled in the art may devise many other modifications and embodiments that fall within the scope and spirit of the present disclosure. DETAILED DESCRIPTION

[0018] Unless otherwise indicated, all numbers used in the specification and claims to express feature sizes, quantities and physical properties should be understood to be modified by the term "about" in all cases. Therefore, unless otherwise indicated, the numerical parameters listed in the above specification and the appended claims are approximate values, which can vary according to the desired properties sought to be obtained by those skilled in the art using the teachings disclosed herein. The use of numerical ranges expressed by endpoints includes all numbers within the range (e.g., 1 to 5 includes 1, 1.5, 2, 2.75, 3, 3.80, 4 and 5) and any range within the range.

[0019] Unless the content clearly dictates otherwise, as used in this specification and the appended claims, the singular forms "a / kind", "the" and "the" encompass embodiments having plural referents. Unless the content clearly dictates otherwise, as used in this specification and the appended claims, the term "or" is generally employed in its sense including "and / or".

[0020] For ease of description, spatially relative terms (including but not limited to "lower," "upper," "beneath," "under," "above," and "on top"), if used herein, are used to describe the spatial relationship of an element(s) relative to another element. Such spatially relative terms encompass different orientations of the device when in use or operation in addition to the specific orientations depicted in the drawings and described herein. For example, if an object depicted in a drawing is turned over or inverted, portions previously described as being below or beneath other elements would now be above those other elements.

[0021] As used herein, for example, when an element, component or layer is described as being "on," "connected to," "coupled to," or "contacting" another element, component or layer, it may be directly on, directly connected to, directly coupled to, or directly contacting the latter, or, for example, an intervening element, component or layer may be on a particular element, component or layer, or connected to, coupled to, or contacting a particular element, component or layer. When an element, component or layer is, for example, referred to as being "directly on," "directly connected to," "directly coupled to," or "directly contacting" another element, for example, there are no intervening elements, components or layers.

[0022] There is often a need for articles with adjustable stiffness and variable resistance to motion. For example, a flexible display can bend and be able to maintain a bent position. At least some embodiments of the present disclosure are directed to an electrostatic squeezing device that produces a controlled resistance to motion. Such squeezing devices can be incorporated into various devices, systems, and structures to resist different motions, such as bending motions, translations, rotations, etc. The motion can be largely planar or along or within a surface.

[0023] Sheets of material may be squeezed together using a vacuum to resist motion. Sheets of material may be squeezed together using static electricity. This eliminates the need for a vacuum source and an airtight envelope. Previous electrostatic squeezing devices have several limitations. Some devices achieve only simple bending of the sheet, which can only be shaped into a deployable surface (or a smooth surface with zero Gaussian curvature). Previous devices tend to be difficult to construct and operate at high voltages.

[0024] At least some embodiments of the present disclosure are directed to an extrusion device that can be used to allow bending in one state and resist bending in another state. In some embodiments, the extrusion device includes a plurality of sheets, and the sheets can be electrostatically squeezed to resist movement. Such an extrusion device includes a conductive layer and a dielectric layer disposed between adjacent conductive layers. At least some embodiments of the present disclosure are directed to an electrostatic extrusion device that can operate at a low voltage but achieve a useful degree of resistance to movement. Low voltage refers to a voltage lower than the breakdown voltage of air at the minimum distance between any two electrically opposite conductive layers. Some existing extrusion devices include a dielectric layer that extends appropriately beyond the conductive layer so that the shortest path in the air between two electrically opposite conductors is much longer than the path through the dielectric layer. This makes it more difficult to manufacture such extrusion devices and makes such extrusion devices more sensitive to pinholes or cracks in the dielectric layer because they will create a distance between the electrically opposite conductors that will allow the air to be broken down (short circuit and arcing). Some embodiments of the extrusion device in the present disclosure will not short circuit or arc even if there are cracks, cuts, pinholes and other defects in the dielectric layer. In some embodiments, the conductive layer is maintained at or above the thickness of the dielectric layer, and the extrusion device is operated at a breakdown voltage below that of air at that distance. In some embodiments, the extruded sheets can be cut from a continuous roll of material without special treatment of the edges of the sheet, and used to assemble the extrusion device. This enables a low-cost, high-speed manufacturing method for electrostatic sheet extrusion devices, where a roll of sheet material is produced and then easily converted into a desired shape and assembled into a device. In some cases, low voltage extrusion devices have the advantages of storing much less energy in the device and being safer to use on and near the human body.

[0025] The breakdown voltage refers to the voltage that will cause the air to break down and become conductive over a gap of a given distance between two conductors. This is also called arcing or sparking across the gap. The breakdown voltage varies with pressure. The present disclosure generally refers to the breakdown voltage of air within the standard pressure range experienced on Earth. In the present disclosure, the breakdown voltage involves the shortest distance through the air (not through other dielectric materials) between any two conductors that are not intentionally electrically connected. In the present disclosure, the value of the breakdown voltage at a given distance and pressure has been studied for many years, and it is generally accepted that Paschen's law is followed at gaps above several microns, but deviates from the law at smaller gaps. The breakdown voltage can be determined using a simplified formula proposed by Babrauskas, Vytenis in "Arc Breakdown in Air over Very Small Gap Distances" (Interflam 2013, Vol. 2, pp. 1489-1498), as provided in the following equation (1):

[0026]

[0027] Where V is the breakdown voltage in volts and d is the distance between the two conductors. The breakdown strength (also called dielectric strength) may be understood as the maximum electric field strength (V / m) that does not lead to a breakdown in the material.

[0028] The squeezed state is used to describe the following conditions: relative movement between two adjacent parts, sheets or structures is resisted by introducing external pressure that squeezes the adjacent parts, sheets or structures together. The relative movement involves sliding, rotational or translational movement between two adjacent parts, sheets or structures in the squeezing device. There is a continuous "squeeze" intensity that requires different forces to overcome the resistance to movement. The external pressure that causes squeezing can come from a mechanical source or the application of a vacuum (so that atmospheric pressure presses the sheets together), electrostatic attraction between sheets, etc. The unsqueezed state (also called the loose state) is used to describe the following conditions: no additional resistance is given to the relative movement between adjacent sheets.

[0029] Figure 1A1 is a cross-sectional schematic diagram of an extrusion device 100A. The extrusion device 100A includes a first sheet 110, a second sheet 120, and a dielectric layer 130A. The first sheet 110 includes a first conductive layer 115. The second sheet 120 includes a second conductive layer 125. The dielectric layer 130A is disposed between the first conductive layer 115 and the second conductive layer 125. In some specific implementations, the first sheet 100 and the second sheet 120 are inextensible and flexible. In some cases, the first sheet 100 and the second sheet 120 are movable relative to each other in a loose state (e.g., slidable, rotatable), and cannot move relative to each other in an extruded state, in which a voltage (V) is applied to the extrusion device 100A. As shown, a high potential V+ is applied to the first conductive layer 115, and a low potential V- is applied to the second conductive layer 125. In some cases, a low voltage can be used to induce the extrusion device 100A to reach an extruded state.

[0030] In some embodiments, the conductive layer (115, 125) may include a metal (e.g., copper, aluminum, steel), which may be a laminated metal layer or foil (e.g., of the same or different metals) that has been annealed or hardened; a conductive polymer, or a material filled with conductive particles such as carbon. In some embodiments, the sheet (110, 120) may include a support layer. The support layer may be made of the following materials: paper or other fiber materials, polymer materials (e.g., polyurethane, polyolefin), composite materials (e.g., carbon fiber), elastomers (e.g., silicone, styrene-butadiene-styrene) or other materials and combinations thereof. In some cases, the support layer has a thickness of not less than 50 microns. In some cases, the support layer has a thickness of not less than 125 microns. In some cases, the support layer and the conductive layer may be combined into one layer. In some cases, the first conductive layer 115 is a coating on the first sheet 110. The conductive coating material may be (e.g.) copper, aluminum, silver, nickel, indium tin oxide, carbon, graphite, etc. In some embodiments, the dielectric layer may include silicon oxide, aluminum oxide, titanium oxide, mixed metal oxides, mixed metal nitrides, barium titanate, or polymers such as polyimide acrylate. In some cases, the dielectric layer may be a dielectric film. In some cases, dielectric layer 130A is a coating on first sheet 110. The coating material may include silicon oxide, aluminum oxide, titanium oxide, mixed metal oxides, mixed metal nitrides, barium titanate, or polymers such as polyimide acrylate.

[0031] In some cases, dielectric layer 130 is very thin. In some cases, dielectric layer 130 has a thickness (D) less than or equal to 10 microns. In some cases, dielectric layer 130 has a thickness (D) less than or equal to 5 microns. In some cases, dielectric layer 130 has a thickness (D) less than or equal to 1 micron. In some cases, the distance between first conductive layer 115 and second conductive layer 125 is no greater than 10 microns. In some cases, the extrusion device uses a low voltage to extrude. In some cases, the low voltage is no greater than 100V. In some cases, such a voltage is less than or equal to the breakdown voltage of the distance between the first conductive layer and the second conductive layer.

[0032] Electrostatic squeezing can be understood by modeling each set of adjacent oppositely charged conductive layers with a dielectric material between them as a parallel plate capacitor. The opposite charges on those layers attract each other. It can be shown that the attractive force produces a compressive pressure on the dielectric material, which can be expressed by equation (2):

[0033]

[0034] where ε r is the relative dielectric constant (or dielectric constant) of the dielectric material, ε0 is the dielectric constant of free space (or the dielectric constant of vacuum or the electrical constant 8.854187817...×10 -12 F / m), V is the voltage potential between the two conductive layers, and d is the distance between the two conductive layers (i.e., the thickness of the dielectric material).

[0035] In some cases, the total thickness of the dielectric material includes one or more layers of dielectric material and may also include some air gaps or debris trapped between conductive layers. When multiple dielectric layers are present (including multiple films, coatings, air, debris, etc.), they can be modeled in series. In this case, each layer can be modeled as a capacitor. capacitor, where A is the total area, d is the thickness of that layer, and ε r is the relative dielectric constant of that layer. The total capacitance of the layers in series can be calculated as Among them C tot is the total capacitance, and C1, C2, ... are the capacitances of the individual layers. The total compression pressure on the dielectric material stack can be calculated as equation (3):

[0036]

[0037] Where P is the pressure on the dielectric material stack, C tot In the above calculation, d totis the total thickness of the dielectric layer (i.e., the distance between two adjacent conductive layers). The average relative dielectric constant of this space between the conductive layers can also be calculated as equation (4):

[0038]

[0039] Electrostatic squeezing allows sliding motion, both translational and rotational, between electrically opposite conductive layers. A sliding interface may exist between a conductive layer and a dielectric layer or between a dielectric layer and another dielectric layer. There may be more than one slidable interface between two adjacent electrically opposite conductive layers. When a voltage is applied, the resulting pressure causes the surfaces of the slidable interfaces to press against each other and resist motion. The resistance to motion can be modeled in the following way: consider two sets of interdigitated sheets squeezed together. The resistance to sliding apart of two identical sets of sheets squeezed by electrostatic squeezing can be calculated as equation (5):

[0040] F=PAμN, (5)

[0041] Where F is the force required to pull the group apart (or push them together), A is the overlap area between the sheets (capacitor area), μ is the coefficient of friction at the sliding interface, and N is the total number of interfaces. This is a simplified model because area, friction, and material properties may not be constant, but can be used to illustrate the main factors in electrostatic squeezing.

[0042] It is necessary to have a large extrusion pressure that can resist a large force. For many applications, it is necessary to use very low voltages, which increases safety and reduces the cost and energy consumption of control electronics. According to equation (2), the extrusion performance (i.e., extrusion pressure) at very low voltages can be improved by increasing the relative dielectric constant of the dielectric layer and by reducing the distance between the conductive layers. Using very thin dielectric layers of about several microns or less than one micron can achieve a large extrusion pressure at ultra-low voltage levels. For example, the International Electrotechnical Commission defines ultra-low voltage devices as devices that do not exceed 120V dc. Other standards in the UK and the United States define ultra-low voltage systems as not exceeding 75V dc or 60V dc. Based on earlier calculations, if the total thickness of the dielectric layer is around 4.4 microns (assuming an average relative dielectric constant of 3), a pressure of about 10% of atmospheric pressure can be achieved at 120V. One of the challenges of ultra-low voltage electrostatic extrusion is to reduce the extrusion pressure by the square of the distance between adjacent conductive layers of opposite electrical properties. If there is debris or a large air gap in the slidable interface between the conductive layers, the extrusion pressure may be too low to achieve a useful resistance to motion, or even to achieve pulling the layers together. For example, if the above 4.4 micron distance is increased to around 9.6 microns due to the 5.2 micron air gap, only 1% of the atmospheric pressure is achieved at 120V. Therefore, a small dielectric distance is required to achieve appropriate extrusion pressure for an extrusion device operating at low voltage. In addition, the air gap not only increases the total dielectric distance, but also reduces the average relative dielectric constant, resulting in a greater reduction in extrusion pressure according to the above equation. Some embodiments of the present disclosure achieve ultra-low voltage extrusion by using very thin dielectric layers and introducing a member to bring the sheets together to reduce the air gap.

[0043] In some cases, the extrusion device 100A includes more than two sheets. The extrusion device 100A includes one or more actuating elements configured to keep the first conductive layer and the second conductive layer close to each other. In some cases, the one or more actuating elements are an enclosure in which the sheets of the extrusion device 100A are arranged. In some cases, the actuating element is a spring element, such as a foam or elastic layer, which applies a small pressure to the layer so that they maintain a slight contact and can then be close enough to be squeezed together by applying a voltage. In some cases, the gap between the conductive layers is completely filled with a dielectric material and only a minimum amount of air or other material.

[0044] In some cases, the dielectric layer 130A covers less than one hundred percent (100%) of the periphery of the first sheet 110. In other words, the extrusion device 100 exposes the first conductive layer 115 at a portion or the entire edge of the sheet 100, which is not covered by the dielectric material at the edge. The exposed conductive layer can facilitate electrical connection. In some cases, the dielectric layer 130A covers less than eighty percent (80%) of the periphery of the first sheet 110. In some cases, the dielectric layer 130A covers less than sixty percent (60%) of the periphery of the first sheet 110. A challenge of an electrostatic extrusion device is to protect the device from electrical breakdown (or dielectric breakdown) to the air. Some existing electrostatic extrusion devices have used high voltages of hundreds of volts to thousands of volts. This requires the extrusion device to include a continuous dielectric layer that extends far beyond the conductive layer, so that the shortest path in the air between the conductive layers is many times longer than the path through the dielectric layer between the conductive layers. This is because the dielectric strength of air at most voltages is only 3 MV / m, while many dielectric materials (such as polyethylene or polyimide) have a dielectric strength of 100 Mv / m or higher. Figure 1A The embodiment illustrated in ( ) solves that problem by using a field strength lower than the breakdown strength of air to achieve a useful extrusion pressure. Additional benefits are obtained from the fact that the actual breakdown strength of air increases significantly at small gap distances, particularly below 10 microns. By operating at a breakdown voltage lower than that of air, some embodiments of the present disclosure achieve a low-cost, efficient manufacturing method in which large rolls of material can be produced. Those rolls may include a structural layer, one or more conductive layers, and one or more dielectric layers. The roll of material can then be cut into many smaller sheets of any shape, electrically connected, mechanically constrained, as described later, and assembled into a finished product. Because the electrostatic sheet extrusion device is operated at a voltage lower than the breakdown voltage of air over the thickness of the dielectric material between adjacent electrically opposite conductive layers, such extrusion devices are protected from electrical breakdown of the air, which can manifest as electrical arcing (or arc discharge) and cause the material to melt or burn. Another advantage of some embodiments of the present disclosure is that there is no need to have small pinholes or cuts or other defects in the dielectric layer. At high voltages, even small pinholes can cause arcing. Some embodiments of the present disclosure not only enable cutting the perimeter of an extruded sheet without an extended dielectric layer, but also enable cutting complex patterns into the extruded sheet which increases the compliance of the sheet and achieves other advantages presented later.

[0045] In some embodiments, the extrusion device 110A may include multiple sheets, such as Figure 1B and Figure 1CExamples illustrated in and described in more detail below. In some cases, the sheet may be solid or patterned, for example, to improve the flexibility (bendability) and / or ductility of the sheet. In some embodiments, the sheet has a pattern to increase flexibility along one or two axes but has a desired stiffness along a third axis. In some embodiments, the sheet has a pattern cut into them so that they are ductile along one or two axes or allow multiple regions of the sheet to move in a plane or along a surface relative to other regions. Patterning can be formed by a variety of methods, including (but not limited to) steel rule die cutting, extrusion, molding, laser cutting, water jetting, machining, stereolithography or other 3D printing, laser ablation, photolithography, chemical etching, rotary die cutting, stamping, other suitable negative or positive processing technology or a combination thereof. The solid and patterned sheets of the present disclosure can be single-layer or multi-layer structures, and can be formed by a variety of materials and material layers as described above.

[0046] In some embodiments, the extrusion apparatus includes two sets of sheets, each set of sheets including a plurality of sheets. Figure 1B An example of an extrusion device 100B having two groups of sheets is depicted. In the illustrated embodiment, the extrusion device 100B includes a first group of sheets 110 and a second group of sheets 120, wherein the first group of sheets and the second group of sheets are interdigitated. Each of the first group of sheets includes a first conductive layer 115. Each of the second group of sheets includes a second conductive layer 125. The extrusion device 100B also includes a group of dielectric layers 130B, wherein adjacent pairs of first conductive layers 115 and second conductive layers 125 have one of the group of dielectric layers 130B disposed therebetween. In some embodiments, the extrusion device 100B includes a first connector 140B that is conductively coupled to at least a portion of the first conductive layer 115 of the first group of sheets 110. In some cases, the extrusion device 100B includes a second connector 150B that is conductively coupled to at least a portion of the second conductive layer 125 of the second group of sheets 120. In some cases, the first group of sheets 110 and the second group of sheets 120 are able to move relative to each other in a loose state; and the first group of sheets 110 and the second group of sheets 120 are squeezed against each other in a squeezed state. In some cases, as illustrated, the squeezed state is induced when a voltage less than or equal to 100V is applied between the first connector 140B and the second connector 150B. In some cases, the squeezed state is induced when a voltage less than or equal to 200V is applied. In some cases, the squeezed state is induced when a voltage less than or equal to the breakdown voltage of air over a distance between adjacent conductive layers of one sheet in the first group of sheets and one sheet in the second group of sheets is applied between the first connector 140B and the second connector 150B.

[0047] In some embodiments, some dielectric layers 132B as part of dielectric layer 130 are coated on the first set of sheets. In some embodiments, some dielectric layers 134B as part of dielectric layer 130 are coated on the second set of sheets. In some cases, each of the dielectric layers is very thin. In some cases, the thickness of each of the dielectric layers is less than or equal to 10 microns. In some cases, the thickness of each of the dielectric layers is less than or equal to 5 microns. In some cases, the thickness of each of the dielectric layers is less than or equal to 1 micron. In some cases, the distance between the first conductive layer and one of the second conductive layers of adjacent pairs in a loose state is no greater than 10 microns. In some cases, the distance between the first conductive layer and one of the second conductive layers of adjacent pairs in a loose state is no greater than 10 microns. In some cases, the distance between the first conductive layer and one of the second conductive layers of adjacent pairs in a loose state is no greater than 5 microns.

[0048] In some cases, the first set of sheets 110 has a first longitudinal axis and the second set of sheets 120 has a second longitudinal axis, and the first longitudinal axis and the second longitudinal axis are parallel to each other. In some cases, the first longitudinal axis and the second longitudinal axis have an angle greater than 0°. In some cases, the first longitudinal axis and the second longitudinal axis have an angle close to 90°.

[0049] The conductive layers and dielectric layers can have various arrangements. Figure 1C An exemplary arrangement of an extrusion device 100C is depicted in FIG, wherein each of the conductive layers is sandwiched between two dielectric layers, for example, conductive layer 115 is sandwiched between two dielectric layers 132B, and conductive layer 125 is sandwiched between two dielectric layers 134B. In this arrangement, there is a slidable interface between the two dielectric layers in the unextruded state, and the total dielectric thickness includes dielectric layer 132B, dielectric layer 134B, and possible air gaps. Figure 1D Another exemplary arrangement of an extrusion device 100D is depicted in , wherein each of the conductive layers (115, 125) includes a core layer 160 having a conductive layer on both surfaces of the core layer, wherein the dielectric layer (132B, 134B) is outside the conductive layer. This multiple layered construction can be constructed by stacking or laminating layers. In some cases, the conductive layer is coated or deposited (e.g., chemically or physically vapor deposited) onto the core layer. In some cases, the core layer 160 provides structural support. In some cases, a dielectric layer is coated or deposited (e.g., chemically or physically vapor deposited) onto the conductive layer. In Figure 1E One other exemplary arrangement of an extrusion device 100E is depicted in FIG. 1 , wherein one of the conductive layers ( 115 , 125 ) beside the core layer 160 has an adjacent dielectric layer ( 132B, 134B).

[0050] Figure 1F An example of an extrusion device 100F is depicted. Extrusion device 100F includes extruded sheets (110, 120), each having a core layer 160, a conductive layer (115, 125) adjacent to core layer 160, and a dielectric layer (132B, 134B) adjacent to the respective conductive layer. In some cases, connectors (140B and 150B) provide mechanical and electrical connections between the sheets. The connectors may include tape, conductive tape, conductive epoxy, conductive adhesive, conductive paste, elastomeric conductors, conductive or non-conductive threads, staples, clamps, rivets, or other fasteners. The mechanical and electrical connections may be achieved by separate components.

[0051] In some embodiments, the sheet in the extrusion device can be provided in the form of a tape. In some cases, the tape is in the form of a roll. Figure 2A One example of an extruded sheet 200 in the form of a continuous tape is shown; Figure 2B An example of an extruded sheet 220B in roll form is shown. The extruded sheet (200, 200B) can have any of the configurations and embodiments described herein. In one example, the extruded sheet 200 has at least Figures 1B to 1E In some cases, the extruded sheet includes a substrate or core layer for support. In some cases, the extruded sheet can have incorporated patterns and features, for example, as in Figure 4A and Figure 4B and described in more detail below.

[0052] In some embodiments, the extruded sheet (200, 200B) can be separated into a first section 210 and a second section 220. In some embodiments, the extruded sheet 200 includes a tear line 240 to allow easy separation of the sections. In some cases, the dielectric layer has a thickness less than or equal to 10 microns. In some cases, the dielectric layer has a thickness less than or equal to 5 microns. In some cases, the dielectric layer has a thickness less than or equal to 1 micron. In some cases, the sheet (200, 200B) is non-extensible and flexible. In some embodiments, the first section and the second section are removed from the extruded sheet 200B by die cutting, laser cutting, rotary die cutting or other suitable techniques.

[0053] In some embodiments, a compression device can be formed by a first section 210 of a sheet and a second section of a sheet 220. In some embodiments, the first section and the second section can move relative to each other in a loose state and squeeze each other in a squeezed state. In some cases, a squeezed state is induced when a voltage is applied between the conductive layer of the first section and the conductive layer of the second section. In some cases, the applied voltage is less than or equal to the breakdown voltage of the distance between the first conductive layer and the second conductive layer. In some cases, the applied voltage is not greater than 100V. In some cases, the applied voltage is not greater than 200V. In some cases, the distance between the conductive layer of the first section and the conductive layer of the second section is not greater than 5 microns. In some cases, the distance between the conductive layer of the first section and the conductive layer of the second section is not greater than 10 microns. In some embodiments, the dielectric layer is a coating on the sheet 200. In some embodiments, the conductive layer is a coating on the sheet 200.

[0054] In some embodiments, the sheet is in various arrangements in the extrusion device to achieve the desired functionality. In some cases, one end of the sheet has a connector, such as Figure 1B and Figure 1C shown in. Figure 3A and Figure 3B Some other examples of arrangements of extruded sheets in an extrusion device are shown. Figure 3ATwo groups of extruded sheets (310, 320) arranged at an angle in an extrusion device 300A are depicted. Each extruded sheet may have any one of the configurations and embodiments as described herein. In some embodiments, each of the first group of extruded sheets 310 and the second group of extruded sheets 320 has a conductive layer. In some embodiments, each of the first group of extruded sheets 310 and the second group of extruded sheets 320 has a conductive layer and a dielectric layer. In some cases, the first group of extruded sheets 310 and the second group of extruded sheets 320 are interdigitated. In some cases, the extruded sheets are arranged so that the dielectric layer is arranged between two adjacent conductive layers. In some cases, the first group of extruded sheets 310 has a connector 330 on two edges that are 331A and 332A, respectively. In the illustrated example, the connector 330 is at two opposite edges. In some cases, the second group of extruded sheets 320 has a connector 340 on two edges that are 341A and 342A, respectively. In the illustrated example, connectors 341A and 342A are disposed proximate two opposing edges. In some cases, connectors 330 and 340 are electrically coupled to some or all of the conductive layers in the extruded sheets (310, 320). In some cases, one of the two connectors (331A, 332A) is electrically coupled to some or all of the conductive layers in the extruded sheet 310. In some cases, one of the two connectors (341A, 342A) is electrically coupled to some or all of the conductive layers in the extruded sheet 320.

[0055] The first group of extruded sheets 310 has a longitudinal axis X, and the second group of extruded sheets 320 has a longitudinal axis Y. In some cases, axis X and axis Y form a degree greater than 0° and less than 180°. In one embodiment, axis X and axis Y form a degree close to 90°. In one embodiment, axis X and axis Y form a degree of about 45°. In one embodiment, axis X and axis Y form a degree of about 130°. In one embodiment depicted, connectors (330, 340) connect the shorter edges of the sheets. In some embodiments, connectors connect the longer edges of the sheets.

[0056] In some embodiments, the first group of sheets 310 and the second group of sheets 320 can move relative to each other in a loose state and squeeze each other in a squeezed state. In some cases, the first group of sheets 310 and / or the second group of sheets 320 can rotate in a loose state. In some cases, a squeezed state is caused when a voltage is applied between the first connector and the second connector. In some cases, the applied voltage is not more than 100V. In some cases, the applied voltage is not more than 200V. In some cases, the applied voltage is less than or equal to the breakdown voltage of the distance between the first conductive layer and the second conductive layer. In some cases, the distance between adjacent conductive layers in a loose state is not more than 10 microns. In some cases, the distance between adjacent conductive layers in a loose state is not more than 5 microns.

[0057] exist Figure 3A In the embodiment shown in the figure, the extrusion device 300A includes enclosures 335 and 345. In some embodiments, enclosures 335 and 345 include connectors 330 and 340. In some embodiments, enclosures 335 and 345 are partially open. In some embodiments, enclosures 335 and 345 are configured to keep extruded sheets 310 and 320 arranged close to each other. In some embodiments, enclosures (335 and / or 345) are flexible. Enclosures 335 and 345 are examples of components that promote close proximity of sheets.

[0058] Figure 3BAnother example of an extrusion device 310B with two groups of extruded sheets (310, 320) is depicted. Each extruded sheet may have any one of the configurations and embodiments described herein. In some embodiments, each of the first group of extruded sheets 310 and the second group of extruded sheets 320 has a conductive layer. In some embodiments, each of the first group of extruded sheets 310 and the second group of extruded sheets 320 has a conductive layer and a dielectric layer. In some cases, the first group of extruded sheets 310 and the second group of extruded sheets 320 are interdigitated. In some cases, the extruded sheets are arranged so that the dielectric layer is arranged between two adjacent conductive layers. In some cases, the first group of extruded sheets 310 has a connector close to two edges, which are 331B and 332B, respectively. In the illustrated example, connectors 331B and 332B are arranged close to two adjacent edges. In some cases, the second group of extruded sheets 320 has a connector 340 on two edges, which are 341B and 342B, respectively. In the illustrated example, connectors 341B and 342B are disposed proximate to two adjacent edges. In some cases, connectors (331B, 332B, 341B, 342B) are electrically coupled to some or all of the conductive layers in the extruded sheets (310, 320). In some cases, one of the two connectors (331B, 332B) is electrically coupled to some or all of the conductive layers in the extruded sheet 310. In some cases, one of the two connectors (341B, 342B) is electrically coupled to some or all of the conductive layers in the extruded sheet 320. Connectors 331B, 332B, 341B, 342B may also include members that cause the sheets to remain in close proximity to each other.

[0059] In some embodiments, the first group of sheets 310 and the second group of sheets 320 can move relative to each other in a loose state and squeeze each other in a squeezed state. In the illustrated example, the first group of sheets 310 and / or the second group of sheets 320 can be rotated or translated according to the arrows. In some cases, the squeezed state is induced when a voltage is applied between the first connector and the second connector. In some cases, the applied voltage is not greater than 100V. In some cases, the applied voltage is not greater than 200V. In some cases, the applied voltage is less than or equal to the breakdown voltage of the distance between the first conductive layer and the second conductive layer. In some cases, the distance between adjacent conductive layers in a loose state is not greater than 10 microns. In some cases, the distance between adjacent conductive layers in a loose state is not greater than 5 microns.

[0060] In some embodiments, the sheet used in the extrusion device can be a solid flat sheet. In some embodiments, the sheet used in the extrusion device can have patterns, protrusions, slits, openings and other features. In some embodiments, the sheet can include a three-dimensional structure, but the sheet is generally flat. Figure 4A and Figure 4B Some examples of sheets with patterns and features are shown. Figure 4A An extruded sheet 400A having a pattern is depicted. In some cases, the extruded sheet 400A is made of a non-extensible material. In some cases, the extruded sheet 400A includes a set of slit features 410A that enable the sheet to be extended on axis X. In some cases, the extruded sheet 400A includes a set of slit features 410A that enable the sheet to be extended on axis Y. In some cases, the extruded sheet 400A includes a conductive layer. In some cases, the extruded sheet 400A includes both a conductive layer and a dielectric layer.

[0061] Figure 4B Another example of an extruded sheet 400B having a pattern that can be used in an extrusion device is shown. In some cases, the pattern includes a set of slit features 410B that allow the sheet to be stretchable in one axis (e.g., axis Y). In some cases, this stretchability gives the sheet increased compliance to bend out of plane along a path in that axis. For example, due to the stretchability along axis Y, a sheet can be more easily bent than a sheet without slits. Figure 4B The sheet in is rolled into a cylinder with its axis aligned along axis X.

[0062] Figure 4C A cross-sectional view showing another example of an extrusion device 400C using extruded sheets 410C and 420C; and Figure 4D The two extruded sheets 410C and 420C are shown when they are separated from each other. In some cases, the extruded sheet 410C includes a substrate 412C. In some cases, the substrate 412C has a common plane 415C. In some cases, the extruded sheet 410C includes a set of features 414C protruding from the substrate 412C. Similarly, the extruded sheet 420C may include a substrate 422C and a set of features 424C protruding from the substrate 424C. In some cases, the extrusion device may be formed by two or more extruded sheets 410C. In some cases, the set of features 414C and the set of features 424C are configured to match each other. In some cases, the extruded sheets 410C and 420C are inextensible and flexible. In some cases, the extruded sheets 410C and / or 420C include a conductive layer. In some cases, the extruded sheets 410C and / or 420C include both a conductive layer and a dielectric layer.

[0063] In some cases, the group of features 414C and 424C has a length of several millimeters. In some cases, the feature has a length less than one millimeter. In some cases, the length of the feature is several microns to 50 microns. The height (H) of the group of features 414C refers to the average height of the group of features 414C relative to the universal plane 415C. In some cases, the height of the group of features 414C is equal to or less than 10 millimeters. In some cases, the height of the group of features 414C is equal to or less than 1 millimeter. In some cases, the height of the group of features 414C is equal to or less than 50 millimeters. In some cases, each of the group of features is a prism, a pyramid, a rectangular protrusion, an elliptical protrusion, a sawtooth or a sinusoidal protrusion. In some cases, the feature is constant along an axis, as if they are squeezed. In some cases, the feature changes along more than one axis, including discrete three-dimensional features. In some cases, the pattern of the feature repeats and in some cases, they are random. For example, random features having a size of a few microns or less may provide a desired coefficient of friction and may also provide some resistance to small debris particles.

[0064] In some embodiments, extruded sheet 410C and extruded sheet 420C are able to move relative to each other in a loose state and to be pressed against each other in a pressed state. In some cases, the pressed state is induced when a voltage is applied to the sheets. In some cases, the applied voltage is no greater than 500V. In some cases, the applied voltage is no greater than 50V. In some cases, the applied voltage is no greater than 100V. In some cases, the applied voltage is no greater than 200V. In some cases, the distance between adjacent conductive layers in a loose state is relatively large, thereby allowing freedom of movement of the two sheets. Figure 4D As shown in , the sheet can be attached to a separate article (462D and 464D). When the articles are put together and the extruded sheets are placed in close proximity and a voltage is applied to induce an extruded state, the articles will then resist moving apart. In some cases, the applied voltage is less than or equal to the breakdown voltage of the distance between the conductive layers on the sheet. In some cases, the distance between adjacent conductive layers in a loose state is no more than 10 microns. In some cases, the distance between adjacent conductive layers in a loose state is no more than 5 microns. In some cases, in an extruded state, some first features match some second features. The matching of the features can produce a significant increase in the resistance to the movement of the sheet caused by shear forces. In some cases, the feature is designed to increase the resistance in a specific direction.

[0065] Figure 4EA cross-sectional view of an example of an extrusion device 400E using extruded sheets 410E and 420E is depicted. In some cases, the extruded sheet 410E includes a substrate and a set of features 414E protruding from the substrate 412E. Similarly, the extruded sheet 420E may include a substrate and a set of features 424E protruding from the substrate. In some cases, the extrusion device may be formed by two or more extruded sheets. In the illustrated example, the features (414E, 424E) are cylindrical or rectangular protrusions. In some cases, the set of features 414E and the set of features 424E are configured to match each other. In some cases, the extruded sheets 410E and 420E are inextensible and flexible. In some cases, the extruded sheets 410E and / or 420E include a conductive layer. In some cases, the extruded sheets 410E and / or 420E include both a conductive layer and a dielectric layer.

[0066] Figure 4F A cross-sectional view of an example of an extrusion device 400F using extruded sheets 410F and 420F is depicted. In some cases, the extruded sheet 410F includes a substrate and a set of features 414F protruding from the substrate 412F. Similarly, the extruded sheet 420F may include a substrate and a set of features 424F protruding from the substrate. In some cases, the extrusion device may be formed by two or more extruded sheets. In the illustrated example, the features (414F, 424F) are sinusoidal protrusions. In some cases, the set of features 414F and the set of features 424F are configured to match each other. In some cases, the extruded sheets 410F and 420F are inextensible and flexible. In some cases, the extruded sheets 410F and / or 420F include a conductive layer. In some cases, the extruded sheets 410F and / or 420F include both a conductive layer and a dielectric layer.

[0067] In some embodiments, the pressing device includes an actuating element that urges the set of sheets to remain close to each other in a loose, unpressed state. Figure 4G An example of an excitation element is shown in , wherein the actuating element includes a highly compliant outer layer 452. In some cases, the actuating element includes a highly compliant inner layer 450. In some cases, the actuating element is made of a stretchable material such as spandex or an elastic material. In some cases, an extruded sheet 400G is contained between the actuating elements. In some cases, the extruded sheet 400G has multiple patterns that allow them to be stretched on any axis so that they can conform to complex surfaces (such as, the human joints shown).

[0068] Compression devices may be used in various flexible devices and equipment to allow the device / equipment to maintain a bent position. Figure 5AAn example of a flexible device 500A having a flexible component layer 510 and a pressing device 520 is depicted. The flexible component layer 510 includes at least one component. The pressing device 520 may have any of the configurations and embodiments of the pressing devices described herein. In some cases, the pressing device 520 is disposed proximate to the flexible component layer 510. In some cases, the pressing device has a loose state and a pressed state, wherein the pressing device permits the flexible component layer to bend in the loose state, and the pressing device is configured to resist bending of the flexible component layer in the pressed state.

[0069] Figure 5B An example of a display 500B using an extrusion device 520B is depicted. In this example, the flexible component layer 510 is a flexible (or bendable) display, or a flexible display panel. The extrusion device 520B may have any of the embodiments and configurations of the extrusion device as described herein. In some cases, the display panel 500B includes two rigid components 530B. For example, the rigid component may also be a part of a heat sink, a battery, an electromagnetic shield, or other components for the display panel 500B. The extrusion device 520B is arranged to be close to the flexible component layer 510B. In some embodiments, the extrusion device covers most of the surface of the flexible component layer. In some cases, the extrusion device may include one or more extrusion elements arranged to be close to the flexible component layer, wherein each extrusion element may have any of the configurations and embodiments of the extrusion device as described herein.

[0070] Figure 6 An example of a flow chart for assembling an electrostatic extrusion device is depicted. One or more steps are optional. First, retrieve a roll of electrostatic extrusion material (step 610). Separate individual extruded sheets from the roll (step 620). The individual sheets may be separated by die cutting, laser cutting, rotary die cutting, or other suitable techniques. Stack the individual sheets into two or more groups (step 630). Electrically connect each group of sheets (step 640). Assemble two or more groups of extruded sheets into an extrusion device (step 650). In some cases, the two or more groups of sheets are arranged in an interdigitated manner.

[0071] Fig. 7A and Figure 7B Some examples of actuating components that may be used in a squeezing device are shown. Fig. 7A An example of an actuation member 720A is shown. As shown, the actuation member is an enclosure with a fixed gap. In this example, the actuation member does not add pressure to the extruded sheet 710. The extruded sheet can use any of the configurations and embodiments shown and provided herein. Figure 7BAnother example of an actuation member 720B is depicted. As depicted, the actuation member 720B is a rivet-style enclosure with a fixed void. In this example, the actuation member does not add pressure to the extruded sheet 710. In some embodiments, a compliant layer (such as foam or springs) can be added to the void area to apply some small pressure to the sheets to urge them together.

[0072] Exemplary embodiments

[0073] Embodiment A1. An electrostatic sheet pressing device comprises: a first sheet having a first conductive layer; a first dielectric layer, the first dielectric layer being arranged adjacent to the first conductive layer; a second sheet, the second sheet comprising a second conductive layer and being arranged close to the first dielectric layer. The first dielectric layer is arranged between the first conductive layer and the second conductive layer. The first dielectric layer has a thickness of less than or equal to 10 microns. The first sheet and the second sheet are inextensible and flexible, wherein the first sheet and the second sheet are able to slide relative to each other in a first state. When a voltage is applied between the first conductive layer and the second conductive layer, the first sheet and the second sheet are pressed against each other in a second state. The applied voltage is less than or equal to the breakdown voltage of air at a distance between the first conductive layer and the second conductive layer.

[0074] Embodiment A2. An extrusion device according to Embodiment A1, wherein the first dielectric layer is a coating on the first sheet.

[0075] Embodiment A3. According to the extrusion device described in embodiment A1 or A2, it also includes a second dielectric layer, wherein the second sheet has a first surface and a second surface opposite to the first surface, wherein the second conductive layer is on the first surface of the second sheet, and wherein the second dielectric layer is arranged to be closer to the second surface of the second sheet than the first surface of the second sheet.

[0076] Embodiment A4. The extrusion device according to any one of Embodiments A1 to A3 further includes: a second dielectric layer, which is arranged to be close to the second sheet.

[0077] Embodiment A5. An extrusion device according to any one of Embodiments A1 to A4, wherein the second dielectric layer is coated on the second sheet.

[0078] Embodiment A6. An extrusion device according to any one of Embodiments A1 to A5, wherein the applied voltage is no greater than 100V.

[0079] Embodiment A7. An extrusion device according to any one of Embodiments A1 to A6, wherein the distance between the first conductive layer and the second conductive layer in the first state is not greater than 10 microns.

[0080] Embodiment A8. According to any one of embodiments A1 to A7, the extrusion device further includes: one or more actuating elements, which are configured to keep the first conductive layer and the second conductive layer close to each other.

[0081] Embodiment A9. An extrusion device according to embodiment A8, wherein the one or more actuating elements include at least one of a highly compliant outer layer, a highly compliant inner layer, a fixed gap limiting element and a spring element.

[0082] Embodiment A10. An extrusion device according to any one of Embodiments A1 to A9, wherein the first dielectric layer covers less than one hundred percent of the perimeter of the first sheet.

[0083] Embodiment A11. An extrusion device according to any one of Embodiments A1 to A10, wherein the first dielectric layer has a thickness less than or equal to 5 microns.

[0084] Embodiment A12. An extrusion device according to any one of Embodiments A1 to A11, wherein a direct path between the first conductive layer and the second conductive layer of at least one portion of the extrusion device is approximately the same length as the distance between the first conductive layer and the second conductive layer in the second state.

[0085] Embodiment A13. An extrusion apparatus according to any one of Embodiments A1 to A12, wherein the first sheet is separated from a large sheet having a conductive layer.

[0086] Embodiment A14. An extrusion apparatus according to embodiment A13, wherein the large sheet is a roll of sheet.

[0087] Embodiment A15. An extrusion apparatus according to any one of Embodiments A1 to A14, wherein the first sheet is patterned so that the first sheet can be extended in at least one axis.

[0088] Embodiment A16. An extrusion device according to any one of Embodiments A1 to A15, wherein the first sheet has patterned openings so that the first sheet can be extended in at least one axis.

[0089] Embodiment A17. An extrusion device according to any one of Embodiments A1 to A16, wherein the first sheet has a plurality of raised features.

[0090] Embodiment A18. An extrusion device according to Embodiment A17, wherein the second sheet has a plurality of raised features.

[0091] Embodiment A19. An extrusion apparatus according to Embodiment A18, wherein in the second state, at least some of the plurality of raised features of the first sheet mate with some of the plurality of raised features of the second sheet.

[0092] Embodiment A20. An extrusion device according to any one of Embodiments A1 to A19, wherein the first dielectric layer has a relative dielectric constant greater than 3.

[0093] Embodiment A21. An extrusion device according to any one of Embodiments A1 to A20, wherein the first dielectric layer comprises an inorganic compound.

[0094] Embodiment A22. An extrusion device according to any one of Embodiments A1 to A21, wherein the coefficient of friction of the first sheet is less than 0.4.

[0095] Embodiment A23. An extrusion device according to any one of Embodiments A1 to A22, wherein the first sheet includes a core layer that provides structural support.

[0096] Embodiment B1. An electrostatic sheet pressing device comprises: a first group of sheets, each of which includes a first conductive layer; a second group of sheets, each of which includes a second conductive layer; a group of dielectric layers; a first connector, the first connector conductively connected to at least a portion of the first conductive layer of the first group of sheets; and a second connector, the second connector conductively connected to at least a portion of the second conductive layer of the second group of sheets. The first group of sheets and the second group of sheets are interdigitated. Each of adjacent pairs of the first group of sheets and the second group of sheets has one of the dielectric layers in the group disposed therebetween. Each of the dielectric layers in the group has a thickness of less than or equal to 10 microns. The first group of sheets and the second group of sheets are capable of sliding relative to each other in a first state. The first group of sheets and the second group of sheets are pressed against each other in a second state when a voltage is applied between the first connector and the second connector, wherein the applied voltage is less than or equal to a breakdown voltage of air at a distance between adjacent conductive layers of one sheet in the first group of sheets and one sheet in the second group of sheets.

[0097] Embodiment B2. An extrusion apparatus according to Embodiment B1, wherein at least some of the dielectric layers in the set of dielectric layers are coated on the first set of sheets.

[0098] Embodiment B3. An extrusion apparatus according to Embodiment B2, wherein at least some of the dielectric layers in the set of dielectric layers are coated on the second set of sheets.

[0099] Embodiment B4. An extrusion device according to any one of Embodiments B1 to B3, wherein the first group of sheets has a first longitudinal axis and the second group of sheets has a second longitudinal axis, and the first longitudinal axis and the second longitudinal axis are substantially parallel to each other.

[0100] Embodiment B5. An extrusion device according to any one of Embodiments B1 to B4, wherein the distance between adjacent pairs of first and second conductive layers in the first state is no greater than 10 micrometers.

[0101] Embodiment B6. An extrusion device according to any of Embodiments B1 to B5, wherein the first dielectric layer covers less than one hundred percent of the perimeter of the first sheet.

[0102] Embodiment B7. An extrusion device according to any one of Embodiments B1 to B6, wherein the applied voltage is no greater than 100V.

[0103] Embodiment B8. The extrusion device according to any one of Embodiments B1 to B7 further includes: one or more actuating elements, wherein the one or more actuating elements are configured to keep the first group of sheets and the second group of sheets close to each other.

[0104] Embodiment B9. An extrusion device according to embodiment B8, wherein the one or more actuating elements include at least one of a highly compliant outer layer, a highly compliant inner layer, a fixed gap limiting element, and a spring element.

[0105] Embodiment B10. An extrusion device according to any of Embodiments B1 to B9, wherein the first dielectric layer covers less than one hundred percent of the perimeter of the corresponding sheet.

[0106] Embodiment B11. An extrusion device according to any of Embodiments B1 to B10, wherein at least one dielectric layer in the set of dielectric layers has a thickness less than or equal to 5 microns.

[0107] Embodiment B12. An extrusion apparatus according to any one of Embodiments B1 to B11, wherein the first group of sheets are separated from a large sheet having a conductive layer.

[0108] Embodiment B13. An extrusion apparatus according to embodiment B12, wherein the large sheet is a roll of sheet.

[0109] Embodiment B14. An extrusion apparatus according to any one of Embodiments B1 to B13, wherein at least one sheet in the first group of sheets is patterned so that the at least one sheet can extend in at least one axis.

[0110] Embodiment B15. An extrusion apparatus according to any one of Embodiments B1 to B14, wherein at least one sheet in the first group of sheets has patterned openings so that the at least one sheet can extend in at least one axis.

[0111] Embodiment B16. An extrusion apparatus according to any one of Embodiments B1 to B15, wherein at least one sheet in the first group of sheets has a plurality of raised features.

[0112] Embodiment B17. An extrusion apparatus according to Embodiment B16, wherein at least one sheet in the first group of sheets has a plurality of raised features.

[0113] Embodiment B18. An extrusion device according to embodiment B17, wherein in the second state, at least some of the multiple protruding features of at least one sheet in the first group of sheets match some of the multiple protruding features of at least one sheet in the second group of sheets.

[0114] Embodiment B19. An extrusion device according to any one of Embodiments B1 to B18, wherein at least one dielectric layer in the set of dielectric layers has a relative dielectric constant greater than 3.

[0115] Embodiment B20. An extrusion device according to any one of Embodiments B1 to B19, wherein at least one dielectric layer in the set of dielectric layers comprises an inorganic compound.

[0116] Embodiment B21. An extrusion device according to any one of Embodiments B1 to B20, wherein the coefficient of friction of at least one sheet in the first group of sheets is less than 0.4.

[0117] Embodiment B22. An extrusion apparatus according to any one of Embodiments B1 to B21, wherein at least one sheet in the first group of sheets comprises a core layer that provides structural support.

[0118] Embodiment C1. An electrostatic sheet pressing device formed of a sheet having a conductive layer and a dielectric layer. The pressing device includes: a first section of the sheet, the first section being separate from the sheet; and a second section of the sheet, the second section being separate from the sheet. The sheet is inextensible and flexible. The first section and the second section are capable of sliding relative to each other in a first state. When a voltage is applied between the conductive layer of the first section and the conductive layer of the second section, the first section and the second section are pressed against each other in a second state.

[0119] Embodiment C2. The extrusion device of embodiment C1, wherein the applied voltage is less than or equal to the breakdown voltage of air at a distance between the first conductive layer and the second conductive layer.

[0120] Embodiment C3. An extrusion device according to embodiment C1 or embodiment C2, wherein the applied voltage is no greater than 100V.

[0121] Embodiment C4. An extrusion device according to any one of Embodiments C1 to C3, wherein the distance between the first segment and the second segment is no greater than 10 microns in the first state.

[0122] Embodiment C5. The extrusion device according to any one of embodiments C1 to C4 further includes: one or more actuating elements, wherein the one or more actuating elements are configured to keep the first section and the second section close to each other.

[0123] Embodiment C6. An extrusion device according to embodiment C5, wherein the one or more actuating elements include at least one of a highly compliant outer layer, a highly compliant inner layer, a fixed gap limiting element, and a spring element.

[0124] Embodiment C7. An extrusion apparatus according to any one of Embodiments C1 to C6, wherein the sheet is packaged in a roll.

[0125] Embodiment C8. An extrusion apparatus according to any one of Embodiments C1 to C7, wherein the sheet includes tear lines between adjacent segments.

[0126] Embodiment C9. An extrusion device according to any one of Embodiments C1 to C8, wherein the coefficient of friction of the sheet is less than 0.4.

[0127] Embodiment C10. An extrusion device according to any one of Embodiments C1 to C9, wherein the dielectric layer of the first segment covers less than one hundred percent of the perimeter of the first segment.

[0128] Embodiment C11. An extrusion device according to any one of Embodiments C1 to C10, wherein the dielectric layer has a thickness less than or equal to 5 microns.

[0129] Embodiment C12. An extrusion device according to any one of Embodiments C1 to C11, wherein a direct path between the first conductive layer and the second conductive layer of at least one portion of the extrusion device is approximately the same length as the distance between the first conductive layer and the second conductive layer in the second state.

[0130] Embodiment C13. An extrusion apparatus according to any one of Embodiments C1 to C12, wherein the first sheet is separated from a large sheet having a conductive layer.

[0131] Embodiment C14. An extrusion apparatus according to embodiment C13, wherein the large sheet is a roll of sheet.

[0132] Embodiment C15. An extrusion apparatus according to any one of Embodiments C1 to C14, wherein the first sheet is patterned so that the first sheet can be extended in at least one axis.

[0133] Embodiment C16. An extrusion device according to any one of Embodiments C1 to C15, wherein the first segment has patterned openings so that the first segment can extend in at least one axis.

[0134] Embodiment C17. An extrusion device according to any one of Embodiments C1 to C16, wherein the first section has multiple protruding features.

[0135] Embodiment C18. An extrusion device according to embodiment C17, wherein the second section has multiple protruding features.

[0136] Embodiment C19. An extrusion device according to embodiment C18, wherein in the second state, at least some of the plurality of raised features of the first section match with some of the plurality of raised features of the second section.

[0137] Embodiment C20. An extrusion device according to any one of Embodiments C1 to C19, wherein the dielectric layer has a relative dielectric constant greater than 3.

[0138] Embodiment C21. An extrusion device according to any one of Embodiments C1 to C20, wherein the dielectric layer comprises an inorganic compound.

[0139] Embodiment C22. An extrusion device according to any one of Embodiments C1 to C21, wherein the sheet includes a core layer that provides structural support.

[0140] Embodiment C23. An extrusion device according to any one of Embodiments C1 to C22, wherein the dielectric layer has a thickness less than or equal to 10 microns.

[0141] Embodiment C24. An extrusion device according to any one of Embodiments C1 to C23, wherein the dielectric layer is a coating on the sheet.

[0142] Embodiment D1. A method comprises the steps of: retrieving a sheet having a conductive layer and a dielectric layer; separating a first group of segments from the sheet; electrically connecting the first group of segments via a first connector; separating a second group of segments from the sheet; electrically connecting the second group of segments via a second connector; and assembling the first group of segments and the second group of segments into a compression device. The sheet is inextensible and flexible. The first group of segments and the second group of segments are capable of sliding relative to each adjacent pair in a first state. When a voltage is applied between the first connector and the second connector, the first group of segments and the second group of segments are compressed together in a second state.

[0143] Embodiment D2. The method of embodiment D1, wherein the dielectric layer is a coating on the sheet.

[0144] Embodiment D3. A method according to embodiment D1 or D2, wherein the dielectric layer has a thickness less than or equal to 10 microns.

[0145] Embodiment D4. The method of any one of Embodiments D1 to D3, wherein the dielectric layer has a thickness less than or equal to 5 microns.

[0146] Embodiment D5. The method according to any one of embodiments D1 to D4 further includes: using one or more actuating elements to assemble the first group of segments and the second group of segments.

[0147] Embodiment D6. A method according to embodiment D5, wherein the one or more actuating elements include at least one of a highly compliant outer layer, a highly compliant inner layer, a fixed gap limiting element, and a spring element.

[0148] Embodiment D7. The method of any one of Embodiments D1 to D6, wherein the sheet is packaged in a roll.

[0149] Embodiment D8. The method of any one of Embodiments D1 to D7, wherein the sheet comprises tear lines between adjacent segments.

[0150] Embodiment D9. The method of any one of Embodiments D1 to D8, wherein the coefficient of friction of the sheet is less than 0.4.

[0151] Embodiment D10. A method according to any one of Embodiments D1 to D9, wherein the dielectric layer of at least one segment in the first group of segments covers less than one hundred percent of the perimeter of the at least one segment in the first group of segments.

[0152] Embodiment D11. The method of any one of Embodiments D1 to D10, wherein a distance between adjacent ones of a segment in the first group of segments and a segment in the second group of segments is no greater than 10 micrometers in the first state.

[0153] Embodiment D12. A method according to any one of embodiments D1 to D11, wherein in the second state, a direct path between two conductive layers of one segment of the first group of segments and one segment of the second group of segments adjacent to each other is approximately the same length as the distance between the two conductive layers.

[0154] Embodiment D13. A method according to any one of Embodiments D1 to D12, wherein the sheet is patterned so that the sheet can be extended along at least one axis.

[0155] Embodiment D14. The method of any one of Embodiments D1 to D13, wherein the sheet has patterned openings such that the sheet is extendable along at least one axis.

[0156] Embodiment D15. The method of any one of Embodiments D1 to D14, wherein the sheet has a plurality of raised features.

[0157] Embodiment D16. A method according to embodiment D15, wherein in the second state, at least some of the multiple protruding features of at least one segment in the first group of segments match some of the multiple protruding features of at least one segment in the second group of segments.

[0158] Embodiment D17. The method of any one of Embodiments D1 to D16, wherein the dielectric layer has a relative dielectric constant greater than 3.

[0159] Embodiment D18. The method of any one of Embodiments D1 to D17, wherein the dielectric layer comprises an inorganic compound.

[0160] Embodiment D19. The method of any one of Embodiments D1 to D18, wherein the sheet comprises a core layer that provides structural support.

[0161] Embodiment D20. The method of any one of Embodiments D1 to D19, wherein the applied voltage is less than or equal to the breakdown voltage of air at a distance between the first conductive layer and the second conductive layer.

[0162] Embodiment D21. The method of any one of Embodiments D1 to D20, wherein the applied voltage is no greater than 100V.

[0163] Embodiment E1. An electrostatic sheet pressing device includes: a first sheet, the first sheet including a first conductive layer, the first sheet including a set of first features protruding from a first general plane of the first sheet; a first dielectric layer, the first dielectric layer is disposed adjacent to the first conductive layer; and a second sheet, the second sheet including a second conductive layer and disposed proximate to the first dielectric layer, the second sheet including a set of second features protruding from a second general plane of the second sheet. The first dielectric layer is disposed between the first conductive layer and the second conductive layer. The first sheet and the second sheet are inextensible and flexible, wherein at least some of the first features in the set of first features are configured to mate with at least some of the second features in the set of second features. The first sheet and the second sheet are movable relative to each other in a first state. When a voltage is applied between the first conductive layer and the second conductive layer, the first sheet and the second sheet are pressed against each other in a second state.

[0164] Embodiment E2. The apparatus of Embodiment E1, wherein the set of first features has a first height representing an average height of the set of first features relative to the first general plane.

[0165] Embodiment E3. An apparatus according to embodiment E2, wherein the first height is equal to or less than 10 mm.

[0166] Embodiment E4. An apparatus according to embodiment E2, wherein the first height is equal to or less than 1 mm.

[0167] Embodiment E5. The apparatus of Embodiment E2, wherein the set of second features has a second height representing an average height of the set of second features relative to the second general plane.

[0168] Embodiment E6. An apparatus according to embodiment E5, wherein the second height is equal to or less than 10 mm.

[0169] Embodiment E7. An apparatus according to embodiment E5, wherein the second height is equal to or less than 1 mm.

[0170] Embodiment E8. The apparatus of any one of Embodiments E1 to E7, wherein one of the set of first features is a prism, a pyramid, a rectangular protrusion, an elliptical protrusion, a sawtooth, or a sinusoidal shape.

[0171] Embodiment E9. The device of any one of Embodiments E1 to E8, wherein the first conductive layer is a coating on the first sheet.

[0172] Embodiment E10. The apparatus of any one of Embodiments E1 to E9, wherein the first dielectric layer is a coating on the first sheet.

[0173] Embodiment E11. The apparatus of Embodiment E10 further comprising: a second dielectric layer coated on the second sheet.

[0174] Embodiment E12. The apparatus of Embodiment E11, wherein the second dielectric layer has a thickness less than or equal to 5 microns.

[0175] Embodiment E13. The apparatus of any one of Embodiments E1 to E12, wherein at least some of the first features in the set of first features have the same first shape.

[0176] Embodiment E14. An apparatus according to Embodiment E13, wherein at least some of the first features in the set of first features have the same second shape.

[0177] Embodiment E15. An apparatus according to embodiment E14, wherein the first shape is the same shape as the second shape.

[0178] Embodiment E16. The apparatus of any one of Embodiments E1 to E15, wherein some of the first features in the set of first features mate with some of the second features in the set of second features in the second state.

[0179] Embodiment E17. An apparatus according to Embodiment E16, wherein the some of the first features in the set of first features are in contact with the some of the second features in the set of second features.

[0180] Embodiment E18. The apparatus of any one of Embodiments E1 to E17, wherein the applied voltage is no greater than a breakdown voltage of the distance between the first conductive layer and the second conductive layer.

[0181] Embodiment E19. The apparatus of any one of Embodiments E1 to E18, wherein the applied voltage is no greater than 100 V.

[0182] Embodiment E20. The apparatus of any one of Embodiments E1 to E19, further comprising: one or more actuating elements configured to hold the first sheet and the second sheet close to each other.

[0183] Embodiment E21. An apparatus according to embodiment E20, wherein the one or more actuation elements include at least one of a highly compliant outer layer, a highly compliant inner layer, a fixed gap limiting element, and a spring element.

[0184] Embodiment E22. The apparatus of any one of Embodiments E1 to E21, wherein the first dielectric layer has a thickness less than or equal to 10 microns.

[0185] Embodiment E23. The apparatus of any one of Embodiments E1 to E22, wherein the first dielectric layer has a thickness less than or equal to 5 micrometers.

[0186] Embodiment E24. The apparatus of any one of Embodiments E1 to E23, wherein the first sheet is separated from a large sheet having a conductive layer.

[0187] Embodiment E25. An apparatus according to embodiment E24, wherein the large sheet is a roll of sheet.

[0188] Embodiment E26. The apparatus of any one of Embodiments E1 to E25, wherein the first sheet is patterned so that the first sheet is extendable in at least one axis.

[0189] Embodiment E27. The device of any one of Embodiments E1 to E26, wherein the first dielectric layer has a relative dielectric constant greater than 3.

[0190] Embodiment E28. The device of any one of Embodiments E1 to E27, wherein the first dielectric layer comprises an inorganic compound.

[0191] Embodiment E29. The apparatus of any one of Embodiments E1 to E28, wherein at least one of the first sheet and the second sheet comprises a core layer that provides structural support.

[0192] Embodiment F1. An electrostatic sheet pressing device comprises: a first group of sheets, each of which includes a first conductive layer; a second group of sheets, each of which includes a second conductive layer; a first connector, the first connector conductively connected to at least a portion of the first conductive layer of the first group of sheets; a second connector, the second connector conductively connected to at least a portion of the second conductive layer of the second group of sheets; and a group of dielectric layers. The first group of sheets is connected on two edges. The second group of sheets is connected on two edges. The first group of sheets and the second group of sheets are interdigitated, wherein each of adjacent pairs of the first group of sheets and the second group of sheets has one of the dielectric layers of the group disposed therebetween. The first group of sheets and the second group of sheets are movable relative to each other in a first state. When a voltage is applied between the first connector and the second connector, the first group of sheets and the second group of sheets are pressed against each other in a second state.

[0193] Embodiment F2. The apparatus of Embodiment F1, wherein at least some of the dielectric layers are coated on the first set of sheets.

[0194] Embodiment F3. An apparatus according to Embodiment F2, wherein at least some of the dielectric layers are coated on the second set of sheets.

[0195] Embodiment F4. The apparatus of any one of Embodiments F1 to F3, wherein the first set of sheets and the second set of sheets are interdigitated having an angle greater than 0 degrees.

[0196] Embodiment F5. The apparatus of any one of Embodiments F1 to F4, wherein the first set of sheets are connected on two opposing edges.

[0197] Embodiment F6. The apparatus of any one of Embodiments F1 to F5, wherein the first set of sheets are connected at two adjacent edges.

[0198] Embodiment F7. An apparatus according to Embodiment F6, wherein the second set of sheets are connected at two adjacent edges.

[0199] Embodiment F8. An apparatus according to embodiment F7, wherein in the first state, the first group of sheets is capable of rotating relative to the second group of sheets.

[0200] Embodiment F9. The apparatus of any one of Embodiments F1 to F8, further comprising: one or more actuating elements configured to hold the first group of sheets and the second group of sheets close to each other.

[0201] Embodiment F10. An apparatus according to embodiment F9, wherein the one or more actuating elements include at least one of a highly compliant outer layer, a highly compliant inner layer, a fixed gap limiting element, and a spring element.

[0202] Embodiment F11. The device of any one of Embodiments F1 to F10, wherein a distance between adjacent pairs of first and second conductive layers in the first state is no greater than 10 micrometers.

[0203] Embodiment F12. The device of any one of Embodiments F1 to F11, wherein a distance between adjacent pairs of first and second conductive layers in the first state is no greater than 5 micrometers.

[0204] Embodiment F13. The apparatus of any one of Embodiments F1 to F12, wherein at least one dielectric layer in the set of dielectric layers has a thickness less than or equal to 10 microns.

[0205] Embodiment F14. The apparatus of any one of Embodiments F1 to F13, wherein at least one dielectric layer in the set of dielectric layers has a thickness less than or equal to 5 microns.

[0206] Embodiment F15. The apparatus of any one of Embodiments F1 to F14, wherein the applied voltage is no greater than 100 V.

[0207] Embodiment F16. An apparatus according to Embodiment F15, wherein the applied voltage is less than or equal to the breakdown voltage of air at a distance between adjacent one of the sheets in the first group of sheets and one of the sheets in the second group of sheets.

[0208] Embodiment F17. The apparatus of any one of Embodiments F1 to F16, wherein the first group of sheets are separated from a large sheet having a conductive layer.

[0209] Embodiment F18. An apparatus according to Embodiment F17, wherein the large sheet is a roll of sheet.

[0210] Embodiment F19. An apparatus according to any one of Embodiments F1 to F18, wherein at least one sheet of the first set of sheets is patterned so that the at least one sheet is extendable in at least one axis.

[0211] Embodiment F20. An apparatus according to any one of Embodiments F1 to F19, wherein at least one sheet of the first set of sheets has patterned openings so that the at least one sheet can be extended in at least one axis.

[0212] Embodiment F21. An apparatus according to any one of Embodiments F1 to F20, wherein at least one sheet in the first set of sheets has a plurality of raised features.

[0213] Embodiment F22. An apparatus according to Embodiment F21, wherein at least one sheet in the first set of sheets has a plurality of raised features.

[0214] Embodiment F23. An apparatus according to embodiment F22, wherein in the second state, at least some of the multiple raised features of at least one sheet in the first group of sheets match some of the multiple raised features of at least one sheet in the second group of sheets.

[0215] Embodiment F24. The apparatus of any one of Embodiments F1 to F23, wherein at least one dielectric layer in the set of dielectric layers has a relative dielectric constant greater than 3.

[0216] Embodiment F25. The device of any one of Embodiments F1 to F24, wherein at least one dielectric layer in the set of dielectric layers comprises an inorganic compound.

[0217] Embodiment F26. An apparatus according to any of Embodiments F1 to F25, wherein the coefficient of friction of at least one sheet in the first set of sheets is less than 0.4.

[0218] Embodiment F27. An apparatus according to any one of Embodiments F1 to F26, wherein at least one sheet in the first group of sheets comprises a core layer that provides structural support.

[0219] Embodiment G1. An electrostatic sheet pressing device includes: a first sheet, the first sheet including a first conductive layer; a first dielectric layer, the first dielectric layer is arranged adjacent to the first conductive layer; a second sheet, the second sheet including a second conductive layer and arranged close to the first dielectric layer. The first dielectric layer is arranged between the first conductive layer and the second conductive layer. The first sheet and the second sheet are made of non-extensible materials and are flexible. The first sheet includes a set of first slit features so that the first sheet can be extended on a first axis. The second sheet includes a set of second slit features so that the second sheet can be extended on a second axis. The first sheet and the second sheet can slide relative to each other in a first state. When a voltage is applied between the first conductive layer and the second conductive layer, the first sheet and the second sheet are locked to each other in a second state.

[0220] Embodiment G2. The apparatus of Embodiment G1, wherein the first conductive layer is a coating on the first sheet.

[0221] Embodiment G3 The device of Embodiment G1 or G2, wherein the first dielectric layer is a coating on the first sheet.

[0222] Embodiment G4. An apparatus according to any one of Embodiments G1 to G3, wherein one of the set of first slit features is an elongated opening, a triangular opening, and an oval opening.

[0223] Embodiment G5. The apparatus of any one of Embodiments G1 to G4, wherein at least one of the first sheet and the second sheet is extendable in an axis.

[0224] Embodiment G6. The apparatus of any one of Embodiments G1 to G5, wherein at least one of the first sheet and the second sheet is extendable in more than one axis.

[0225] Embodiment G7. The apparatus of any one of Embodiments G1 to G6, further comprising: one or more actuating elements configured to hold the first sheet and the second sheet close to each other.

[0226] Embodiment G8. A device according to embodiment G7, wherein each of the one or more actuation elements includes a highly compliant outer layer.

[0227] Embodiment G9. A device according to embodiment G7, wherein each of the one or more actuating elements includes a highly compliant inner layer.

[0228] Embodiment G10. A device according to embodiment G7, wherein at least one of the one or more actuating elements is made of a stretchable material.

[0229] Embodiment G11. An apparatus according to any one of Embodiments G1 to G10, wherein the second axis is parallel to the first axis.

[0230] Embodiment G12. The apparatus of any one of Embodiments G1 to G11, further comprising: a second dielectric layer coated on the second sheet.

[0231] Embodiment G13. The apparatus of any one of Embodiments G1 to G12, wherein the applied voltage is no greater than a breakdown voltage of the distance between the first conductive layer and the second conductive layer.

[0232] Embodiment G14. An apparatus according to any one of Embodiments G1 to G13, wherein the applied voltage is no greater than 100V.

[0233] Embodiment G15. The apparatus of any one of Embodiments G1 to G14, wherein the first dielectric layer has a thickness less than or equal to 10 microns.

[0234] Embodiment G16. A device according to any one of Embodiments G1 to G15, wherein the first dielectric layer has a thickness less than or equal to 5 microns.

[0235] Embodiment G17. An apparatus according to any one of Embodiments G1 to G16, wherein the first sheet is separated from a large sheet having a conductive layer.

[0236] Embodiment G18. An apparatus according to embodiment G17, wherein the large sheet is a roll of sheet.

[0237] Embodiment G19. An apparatus according to any one of Embodiments G1 to G18, wherein the first sheet is patterned so that the first sheet can be extended in at least one axis.

[0238] Embodiment G20. A device according to any one of Embodiments G1 to G19, wherein the first dielectric layer has a relative dielectric constant greater than 3.

[0239] Embodiment G21. The device of any one of Embodiments G1 to G20, wherein the first dielectric layer comprises an inorganic compound.

[0240] Embodiment G22. The apparatus of any one of Embodiments G1 to G21, wherein at least one of the first sheet and the second sheet comprises a core layer that provides structural support.

[0241] Embodiment H1. A flexible electronic device comprising: a flexible component layer, the flexible component layer comprising at least one electronic component; and a pressing device, the pressing device being disposed proximate to the flexible component layer. The pressing device permits bending of the flexible component layer in a first state. The pressing device is configured to resist bending of the flexible component layer in a second state.

[0242] Embodiment H2. An electronic device according to embodiment H1, wherein the extrusion device includes multiple sheets.

[0243] Embodiment H3. An electronic device according to embodiment H2, wherein the plurality of sheets include a conductive layer, so that the pressing device is capable of electrostatic pressing.

[0244] Embodiment H4. An electronic device according to embodiment H2, wherein the extrusion device is capable of vacuum extrusion.

[0245] Embodiment H5. An electronic device according to embodiment H2, wherein at least some of the plurality of sheets substantially conform to the major surface of the flexible component layer.

[0246] Embodiment H6. An electronic device according to embodiment H2, wherein at least some of the plurality of sheets are substantially perpendicular to the major surface of the flexible component layer.

[0247] Embodiment H7. An electronic device according to any one of embodiments H1 to H6, wherein the electronic device is a display.

[0248] Embodiment H8. An electronic device according to any one of embodiments H1 to H7, wherein the electronic device is a wearable electronic device.

[0249] Embodiment H9. An electronic device according to embodiment H3, wherein the plurality of sheets include a first group of sheets and a second group of sheets, wherein the first group of sheets and the second group of sheets are interdigitated, and wherein a second state is triggered when a voltage is applied between the first group of sheets and the second group of sheets.

[0250] Embodiment H10. The electronic device according to embodiment H9 further includes a set of dielectric layers.

[0251] Embodiment H11. An electronic device according to embodiment H10, wherein at least some of the dielectric layers in the set of dielectric layers are coated on the first set of sheets.

[0252] Embodiment H12. An electronic device according to embodiment H11, wherein at least some of the dielectric layers in the set of dielectric layers are coated on the second set of sheets.

[0253] Embodiment H13. An electronic device according to any one of Embodiments H9 to H12, wherein the distance between adjacent pairs of first conductive layers and second conductive layers in the first state is no greater than 10 micrometers.

[0254] Embodiment H14. An electronic device according to any one of Embodiments H9 to H13, wherein the first dielectric layer covers less than one hundred percent of the perimeter of the first sheet.

[0255] Embodiment H15. An electronic device according to any one of embodiments H9 to H14, wherein the applied voltage is less than or equal to the breakdown voltage of air at a certain distance between one sheet in the first group of adjacent sheets and one sheet in the second group of adjacent sheets.

[0256] Embodiment H16. An electronic device according to any one of Embodiments H9 to H15, wherein the applied voltage is no greater than 100V.

[0257] Embodiment H17. The electronic device according to any one of embodiments H9 to H16 further includes: one or more actuating elements, which are configured to keep the first group of sheets and the second group of sheets close to each other.

[0258] Embodiment H18. An electronic device according to embodiment H17, wherein the one or more actuating elements include at least one of a highly compliant outer layer, a highly compliant inner layer, a fixed gap limiting element, and a spring element.

[0259] Embodiment H19. An electronic device according to any one of embodiments H9 to H18, wherein at least one dielectric layer in the set of dielectric layers has a thickness less than or equal to 10 microns.

[0260] Embodiment H20. An electronic device according to any one of embodiments H9 to H19, wherein at least one dielectric layer in the set of dielectric layers has a thickness less than or equal to 5 microns.

[0261] Embodiment H21. An electronic device according to any one of Embodiments H9 to H20, wherein the first group of sheets are separated from a large sheet having a conductive layer.

[0262] Embodiment H22. An electronic device according to embodiment H21, wherein the large sheet is a roll of sheets.

[0263] Embodiment H23. An electronic device according to any one of Embodiments H2 to H22, wherein at least one sheet in the group of sheets is patterned so that at least one sheet in the group of sheets can extend along at least one axis.

[0264] Embodiment H24. An electronic device according to any one of Embodiments H2 to H23, wherein at least one sheet in the first group of sheets has a patterned opening so that the at least one sheet can extend in at least one axis.

[0265] Embodiment H25. An electronic device according to any one of Embodiments H9 to H24, wherein at least one sheet in the first group of sheets has a plurality of raised features.

[0266] Embodiment H26. An electronic device according to embodiment H25, wherein at least one sheet in the second group of sheets has a plurality of raised features.

[0267] Embodiment H27. An electronic device according to embodiment H26, wherein in the second state, at least some of the multiple protruding features of at least one sheet in the first group of sheets match some of the multiple protruding features of at least one sheet in the second group of sheets.

[0268] Embodiment H28. An electronic device according to embodiment H10, wherein at least one dielectric layer in the group of dielectric layers has a relative dielectric constant greater than 3.

[0269] Embodiment H29. An electronic device according to embodiment H10, wherein at least one dielectric layer in the set of dielectric layers comprises an inorganic compound.

[0270] Embodiment H30. An electronic device according to any one of embodiments H2 to H29, wherein the coefficient of friction of at least one sheet in the group of sheets is less than 0.4.

[0271] Embodiment H31. An electronic device according to any one of Embodiments H2 to H30, wherein at least one sheet in the group of sheets includes a core layer that provides structural support.

[0272] Example

[0273] Example 1

[0274] A 0.030 micron thick copper layer was sputter coated as a conductive layer on a roll of polyethylene terephthalate (PET) having a thickness of 0.002 inches (0.00508 cm), and then a 0.050 micron thick silicon oxide aluminum layer was reactively sputter coated on the copper layer as a dielectric layer. Eighteen sheets were cut from the roll into strips 6 inches (15.24 cm) wide and 15 inches (18.1 cm) long. The strips were assembled into double-sided electrostatically extruded sheets by placing groups of two sheets with the flat PET surfaces touching. Figure 1F As shown in , the double-sided electrostatically extruded sheets are then assembled into two sets of interdigitated sheets. Figure 1F As shown in , the two sets of sheets are electrically and mechanically connected together using conductive tape. The strip is laid flat on a workbench, as shown in Figure 8 As shown in , the long axis of one group is perpendicular to the other group. Subsequently, one of the groups is fixed to a workbench, and two aluminum weights (total mass is 17.95g) are placed on the intersection of the group to force them to approach without excessive pressure. Different voltages are applied between the groups of extruded sheets, and a group of extruded sheets is slowly pulled using a Chatillon DFS-050 digital dynamometer (available from Ametek, Berwyn, Pennsylvania, USA). The average force required to pull the group is recorded. Multiple groups of 3 tests are carried out at a certain voltage level, and 3 tests under zero voltage are carried out between each group of power-on tests. The applied voltages and the averaged forces of all tests are summarized in Table 1.

[0275] Table 1

[0276] Experimental Group# Voltage (V) Average force (N) 1 0 0.67 2 5 0.75 3 0 0.63 4 10 0.96 5 0 0.68 6 15 2.07 7 0 0.61 8 20 3.83 9 0 0.76

[0277] The results show that large pressures can be achieved at very low voltage levels. The consistent return to lower forces at zero voltage demonstrates that electric fields strong enough to polarize the material or eject space charge into the system have not yet been generated. The results match well with the model as discussed above. They are consistent with R 2 The expected quadratic relationship is 0.994. 2) and N = 9 interfaces, the friction coefficient can be estimated from the zero voltage data to be μ = 0.044. The extrusion pressure caused by electrostatic extrusion at 20 V is estimated to be about 416 Pa.

[0278] The present invention should not be considered to be limited to the specific examples and embodiments described above, because such embodiments are described in detail to facilitate the explanation of various aspects of the present invention. On the contrary, the present invention should be understood to cover all aspects of the present invention, including various modifications, equivalent processes and alternative devices that fall within the essence and scope of the present invention as defined by the appended claims and their equivalents.

Claims

1. An electrostatic sheet extrusion device, comprising: a first sheet material, the first sheet material comprising a first conductive layer, a first dielectric layer, the first dielectric layer being disposed adjacent to the first conductive layer, a second sheet including a second conductive layer and disposed proximate to the first dielectric layer, wherein the first dielectric layer is disposed between the first conductive layer and the second conductive layer, and one or more actuating elements configured to hold the first conductive layer and the second conductive layer in close proximity to each other to reduce an air gap between the first conductive layer and the second conductive layer when the first conductive layer and the second conductive layer are in a loose, uncompressed state, wherein the first dielectric layer has a thickness less than or equal to 10 micrometers, wherein the first sheet and the second sheet are inextensible and flexible, wherein the first sheet and the second sheet are slidable relative to each other in a first state, wherein in a second state when a voltage is applied between the first conductive layer and the second conductive layer, the first sheet and the second sheet are pressed against each other, and The applied voltage is less than or equal to a breakdown voltage of air at a distance between the first conductive layer and the second conductive layer.

2. The extrusion device of claim 1, wherein the first dielectric layer is a coating on the first sheet.

3. The extrusion device according to claim 1 further includes a second dielectric layer, wherein the second sheet has a first surface and a second surface opposite to the first surface, wherein the second conductive layer is on the first surface of the second sheet, and wherein the second dielectric layer is arranged to be closer to the second surface of the second sheet than to the first surface of the second sheet.

4. The extrusion device of claim 3, wherein the second dielectric layer is coated on the second sheet.

5. The extrusion device according to claim 1, wherein the applied voltage is not more than 100V. 6 . The extrusion device according to claim 1 , wherein the distance between the first conductive layer and the second conductive layer is not greater than 10 micrometers in the first state.

7. The extrusion device of claim 1, wherein the one or more actuating elements include at least one of a highly compliant outer layer, a highly compliant inner layer, a fixed gap limiting element, and a spring element.

8. The extrusion device of claim 1, wherein the first dielectric layer has a thickness less than or equal to 5 microns.

9. The extrusion device of claim 1, wherein a direct path between the first conductive layer and the second conductive layer for at least one portion of the extrusion device is substantially the same length as the distance between the first conductive layer and the second conductive layer in the second state.

10. An electrostatic sheet extrusion device, comprising: a first set of sheets, each sheet comprising a first conductive layer, a second set of sheets, each sheet comprising a second conductive layer, A set of dielectric layers, a first connector conductively connected to at least a portion of the first conductive layer in the first set of sheets, a second connector conductively connected to at least a portion of the second conductive layer in the second set of sheets, and one or more actuating elements configured to hold the first conductive layer and the second conductive layer in close proximity to each other to reduce an air gap between the first conductive layer and the second conductive layer when the first conductive layer and the second conductive layer are in a loose, uncompressed state, wherein the first set of sheets and the second set of sheets are interdigitated, wherein each of adjacent pairs of the first set of sheets and the second set of sheets has disposed therebetween one dielectric layer of the set of dielectric layers, wherein each of the set of dielectric layers has a thickness less than or equal to 10 microns, wherein the first set of sheets and the second set of sheets are able to slide relative to each other in a first state, wherein in a second state when a voltage is applied between the first connector and the second connector, the first group of sheets and the second group of sheets are pressed against each other, and Wherein the applied voltage is less than or equal to the breakdown voltage of air at the distance between adjacent conductive layers of one sheet in the first group of sheets and one sheet in the second group of sheets. 11 . The extrusion device of claim 10 , wherein a distance between adjacent pairs of the first conductive layer and the second conductive layer in the first state is no greater than 10 micrometers.

12. The pressing device of claim 10, wherein the applied voltage is less than 100V.

13. The extrusion apparatus of claim 10, wherein at least one sheet of the first set of sheets is patterned such that the at least one sheet is extendable in at least one axis.

14. The extrusion apparatus of claim 10, wherein at least one sheet in the first set of sheets has a plurality of raised features.

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