Implementation Structure

Abstract

The present invention addresses the problems of: providing a mounting structure in which, when the mounting structure is linked and a linked structure is formed, the arrangement of an electronic component is insusceptible to being disarrayed across the entire surface of the linked structure; and providing a mounting structure that does not require a separate member for installation and that can be installed independently. As a solution to the aforementioned problems, there are provided: a mounting structure having a plurality of electronic components joined by soldering to one surface side of a flexible substrate, the flexible substrate being provided with a linking region in at least part of the periphery thereof, and there being formed, in the linking region, a plurality of linking holes that correspond to the positions at which the electronic components are arranged; and a mounting structure having an electronic device that is provided with a linked structure in which an adjacent mounting structure is linked once electronic components of one mounting structure are fitted into linking holes in the other mounting structure and that is also provided with a plurality of electronic components joined by soldering to one surface side of a flexible substrate, and a double-sided adhesive sheet having recesses or holes that correspond to at least some of the electronic components.

Description

[Technical Field]

[0001] The present invention relates to a mounting structure having a plurality of electronic components mounted on a flexible substrate. [Background technology]

[0002] In Patent Document 1, the applicant proposes a mounting structure in which multiple electronic components are mounted on a flexible substrate, and as an example of this mounting structure, a sheet-like display in which multiple LED elements are arranged on a flexible substrate.

[0003] Patent Document 1 also proposes arranging multiple sheet displays to create a larger screen. The sheet display described in Patent Document 1 is formed on a sheet made of thermoplastic resin, so it is flexible and cannot be arranged by itself; it must be fixed to a frame or the like. In this case, the arrangement of the LED elements between adjacent sheet displays may become distorted, which can make the connected large screen look unnatural.

[0004] Patent Document 1 proposes an application example in which this sheet-like display is attached to a show window in a busy shopping district, and when it is not emitting light, the interior of the store can be seen like a normal show window, but when it is desired to highlight a product or when it is not desired to show the interior of the store, it can be lit up. In the sheet-like display described in Patent Document 1, the LED elements are provided in a protruding state on one side of the flexible substrate, so that the side on which the LED elements are provided is not flat, making it difficult to provide an adhesive layer or the like on this surface. Therefore, this sheet-like display is attached by providing an adhesive layer or the like on the other side of the flexible substrate. When an adhesive layer is provided on the other side of the sheet-like display described in Patent Document 1 and the display is attached to a show window, it is necessary to attach the display to the outdoor surface of the show window and then install a protective body such as a plastic plate on the front surface of the display to protect the LED elements, or to install a separate support such as a frame on the inside of the show window and attach the display to this support. As such, the sheet-like display of Patent Document 1 is difficult to install by itself and requires a separate member such as a protective body or support. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent No. 6738057 Summary of the Invention [Problem to be solved by the invention]

[0006] The problem that the invention aims to solve is to provide a mounting structure (I) in which the arrangement of electronic components is less likely to be disturbed across the entire surface of the connected structure when the mounting structures are connected to form a connected mounting structure (hereinafter sometimes referred to as a "connected structure"), and to provide a mounting structure (II) that does not require any additional components for installation and can be installed independently. [Means for solving the problem]

[0007] The means for solving the problems of the present invention are as follows. Item 1: A flexible substrate having a plurality of electronic components soldered on one side thereof; the flexible substrate has a connecting region along at least a portion of its periphery; A mounting structure, wherein a plurality of connection holes corresponding to the positions at which the electronic components are arranged are formed in the connection region. Item 2: The mounting structure according to Item 1, wherein the flexible substrate is in the shape of a triangle, a rectangle, a pentagon, or a hexagon. Item 3: The mounting structure according to item 1 or 2, which has a removable adhesive layer on at least the other side of the connecting region. Item 4: A mounting structure comprising a plurality of mounting structures according to any one of items 1 to 3 connected together; A coupled mounting structure is one in which adjacent mounting structures are coupled together by fitting an electronic component of one mounting structure into a coupling hole of the other mounting structure. Item 5: The mounting structure according to any one of items 1 to 4, comprising a double-sided adhesive sheet having a recess or hole corresponding to at least a part of the electronic component. Item 6: An electronic device comprising a plurality of electronic components soldered onto one side of a flexible substrate; a double-sided adhesive sheet having a recess or hole corresponding to at least a portion of the electronic component; 1. A mounting structure comprising: Item 7: The mounting structure according to Item 5 or 6, wherein the double-sided adhesive sheet is removable. Item 8: The mounting structure according to any one of items 1 to 7, wherein the electronic component includes one or more of a light emitting element, a sensor element, and a solar cell. [Effects of the Invention]

[0008] The mounting structure (I) of the present invention can be enlarged by connecting them to form a connected structure, and furthermore, it remains flexible even after being connected. When the mounting structure (I) of the present invention is formed into a connected structure, electronic components can be arranged very uniformly across the entire surface of the connected structure. For example, a connected structure formed by connecting mounting structures (I) (sheet-like displays) on which light-emitting elements are mounted as electronic components can display natural images without any disturbance in the arrangement of light-emitting elements. A connected structure formed by connecting mounting structures (I) (sheet-like sensors) on which sensors are mounted as electronic components can measure in-plane distribution information such as temperature and pressure at desired positions. A mounting structure (I) on which solar cells are mounted as electronic components has high power generation efficiency because there is little area where solar cells are not arranged, and can also be formed into curved shapes, which was difficult with conventional solar cells. Mounting structures (I) in which the flexible substrate is triangular, rectangular, or hexagonal can be laid out without gaps on a flat surface, allowing for connection structures of any size. Furthermore, mounting structures (I) in which the flexible substrate is triangular, rectangular, pentagonal, or hexagonal can be made into three-dimensional connection structures as polyhedrons. Furthermore, by connecting mounting structures (I) of different shapes, connection structures of complex shapes such as company logos or characters can be made, and even connection structures that are very close to spherical, such as truncated icosahedrons (the so-called soccer ball shape), can be made.

[0009] In the mounting structure (II) of the present invention, electronic components are housed in recesses or holes in the double-sided adhesive sheet, and the height position of the adhesive surface is approximately uniform, so that the mounting structure (II) alone can be attached to an object and installed. The mounting structure (II) of the present invention is flexible, so it can be attached to curved surfaces. When the mounting structure (II) of the present invention is attached to an object, the double-sided adhesive sheet maintains a gap between the flexible substrate and the object, so that even if the flexible substrate is pressed against the object, the electronic components are less likely to come into contact with the object, preventing failure of the electronic components. The mounting structure (II) in which light-emitting elements are mounted as electronic components can be used as a sheet-like display with high brightness and good appearance. The mounting structure (II) in which sensors are mounted as electronic components can be used as a sheet-like sensor with high measurement accuracy because the measurement target and the sensor are positioned close to each other. The mounting structure (II) in which solar cells are mounted as electronic components can be used as a sheet-like solar cell with high sunlight utilization efficiency and excellent power generation efficiency. [Brief explanation of the drawings]

[0010] [Figure 1] 1 is a schematic diagram of a first embodiment of a mounting structure (I) of the present invention. [Figure 2] A cross-sectional view of A-A' in Figure 1. [Figure 3] FIG. 1 is a schematic diagram of a connected structure in which first embodiments of the mounting structure (I) of the present invention are connected. [Figure 4] A cross-sectional view of A-A' in Figure 3. [Figure 5] FIG. 4 is an enlarged perspective view of a connecting portion of the connecting structure shown in FIG. 3. [Figure 6] FIG. 1 is a schematic diagram of a second embodiment of the mounting structure (I) of the present invention. [Figure 7] A cross-sectional view of A-A' in Figure 6. [Figure 8] 1 is a schematic diagram of an embodiment of a mounting structure (II) of the present invention. [Figure 9] A cross-sectional view of A-A' in Figure 8. [Explanation of symbols]

[0011] Mounting structure 100, 200, 300 Flexible base material 10 Electronic Components 20 Electronic component side terminal 21 Consolidated area 30 Connection hole 40 Removable adhesive layer 50 Conductive Pad 60 Solder 70 Circuit side terminal 80 Connected structure 110 Electronic Devices 500 Double-sided adhesive sheet 600 Hole 610 DETAILED DESCRIPTION OF THE INVENTION

[0012] The mounting structure (I) of the present invention has a plurality of electronic components solder-bonded to one surface of a flexible substrate, the flexible substrate having a connecting region along at least a portion of its periphery; A plurality of connecting holes corresponding to the positions where the electronic components are arranged are formed in the connecting region.

[0013] The mounting structure (II) of the present invention comprises an electronic device having a plurality of electronic components solder-bonded to one side of a flexible substrate, and a double-sided adhesive sheet having recesses or holes corresponding to at least some of the electronic components.

[0014] The mounting structures (I) and (II) of the present invention will be described below along with their embodiment examples. The mounting structures (I) and (II) of the present invention are not limited to the following embodiments, but may include various modifications, changes, and improvements to the disclosed elements (including elements described in the claims, specification, and drawings) within the scope of the present invention and based on the technical concept of the present invention. Furthermore, various combinations, substitutions, and selections of the disclosed elements are possible within the scope of the technical concept of the present invention.

[0015] [Implementation Structure (I)] <First embodiment example> A schematic diagram of a mounting structure 100, which is a first embodiment example of a mounting structure (I) of the present invention, is shown in FIG. 1, and a partial cross-sectional view taken along the line A-A' in FIG. 1 is shown in FIG. 2. Note that in this specification, the drawings are merely schematic diagrams and do not reflect actual dimensions, thickness, etc. Also, in this specification, the use of the same reference numerals in different drawings indicates similar or identical items or features.

[0016] The mounting structure 100 has a plurality of electronic components 20 arranged in a square lattice pattern mounted by soldering on one surface of a rectangular flexible substrate 10. The flexible substrate 10 has a connecting region 30 at the end of one of its short sides, which is its periphery, and a plurality of connecting holes 40 are formed in the connecting region 30 at positions corresponding to the arrangement positions of the electronic components 20, i.e., at positions that form the same square lattice as the electronic components 20 arranged in the square lattice pattern.

[0017] (electronic parts) The type of electronic component 20 is not particularly limited and can be selected appropriately depending on the application of the mounting structure (I) (mounting structure 100), and two or more different types of electronic components can also be mounted. The mounting structure (I) (mounting structure 100) in which light-emitting elements such as LEDs and ELs are mounted as electronic components can be used as a sheet-like display. For example, the mounting structure (I) (mounting structure 100) in which full-color LEDs with built-in control units (hereinafter also referred to as LED elements) are mounted functions as a full-color display device because signals sent to each LED element can be independently controlled from an external main control unit to make each LED element emit or extinguish light in a desired color. The mounting structure (I) (mounting structure 100) that mounts sensors such as temperature, pressure, electric field, magnetic, and light sensors as electronic components can be used as a sheet-like sensor. Also, by alternately arranging two or more types of sensors, such as temperature sensors and pressure sensors, it is possible to obtain in-plane distribution information of two or more different types of measurement data with a single sheet-like sensor. The mounting structure (I) (mounting structure 100) in which solar cells are mounted as electronic components can be used as a sheet-like solar cell. When the mounting structure (I) (mounting structure 100) of the present invention is connected, no area is created in the connected portion where no electronic components are present, so the entire surface can be used for power generation, resulting in high power generation efficiency. Furthermore, the mounting structure (I) (mounting structure 100) of the present invention and the connected structure formed by connecting these structures are flexible, so this sheet-like solar cell can be installed on a curved surface.

[0018] The electronic components 20 are arranged in a square lattice pattern on one surface of the flexible substrate 10. The arrangement of the electronic components 20 is not particularly limited, and they can be arranged at a constant pitch on one surface of the flexible substrate 10, or they can be arranged in any arrangement on one surface of the flexible substrate 10. The arrangement of the electronic components 20 is preferably a square lattice pattern or a regular triangular lattice pattern, since this allows the electronic components 20 to be arranged at equal intervals and with high density. The number of electronic components 20 is not particularly limited and can be determined appropriately depending on the density of electronic components 20 desired in the mounting structure (I) (mounting structure 100). For example, the number of electronic components 20 can be set to 1 / 100 cm. 2 ~4000 pieces / 100cm 2 , preferably 30 pieces / 100cm 2~3000 pieces / 100cm 2 , more preferably 60 pieces / 100cm 2 ~3000 pieces / 100cm 2 , and more preferably 80 pieces / 100cm 2 ~2500 pieces / 100cm 2 It can be said that:

[0019] The shape of electronic component 20 is not limited to the rectangular shape shown in Fig. 1, and examples thereof include a circle, a polygon, an ellipse, etc. Furthermore, the size of electronic component 20 is not particularly limited, but in order to maintain the flexibility of the mounting structure (I) (mounting structure 100), for example, it is preferably 5 mm or less × 5 mm or less in plan view, more preferably 3 mm or less × 3 mm or less, and even more preferably 2 mm or less × 2 mm or less.

[0020] (Flexible base material) The flexible substrate 10 is made of an insulating material. For example, it is not particularly limited as long as it is an insulating material such as a resin film, paper, or cloth and has flexibility. It is preferable to have a resin film because it is easy to impart the desired physical properties. Examples of resins that can be used to form the resin film include, without particular limitation, polyester resins, polyamideimide resins, polyimide resins, polyamide resins, polyether ether ketone resins, polysulfone resins, polyphenylene sulfide resins, polysulfone resins, polyethersulfone resins, fluororesins, ABS resins, polyphenylene oxide resins, acrylic resins, polycarbonate resins, polybutadiene resins, polyurethane resins, polyolefin resins, polyvinyl chloride resins, and polystyrene resins. The resin may also be a mixture of these resins, and may contain functional materials such as colorants, ultraviolet absorbers, infrared reflective materials, and light scattering particles, as required. Furthermore, the material may be a laminate formed by combining any of these resin films, papers, and cloths.

[0021] The thickness of the flexible substrate 10 is not particularly limited as long as it has flexibility, and may be, for example, 1 μm or more and 500 μm or less. From the viewpoint of strength and flexibility, the thickness is preferably 10 μm or more and 300 μm or less, and more preferably 20 μm or more and 100 μm or less. The optical properties of the flexible substrate 10 are not particularly limited and may be any of colorless and transparent, colored and transparent, translucent, and opaque, and can be appropriately selected depending on the application and installation location of the mounting structure (I) (mounting structure 100). The shape of the flexible substrate 10 is not particularly limited, and may be a polygon other than a rectangle, a circle, or an irregular shape.

[0022] In the first embodiment, the flexible substrate 10 is rectangular and has a connecting region 30 at the end of one of its short sides, which is its periphery. The connecting region 30 has a width approximately equal to two rows of the arranged electronic components 20. The connecting region 30 has a width equal to at least one row of the arranged electronic components 20, and preferably has a width equal to three rows or less. In the connecting region 30, a plurality of connecting holes 40 are formed at positions corresponding to the arrangement positions of the electronic components 20, that is, at positions that form the same square lattice as the electronic components 20 arranged in a square lattice pattern. The shape of connecting hole 40 is not limited to the circle shown in Fig. 1, and may be, for example, a polygon, an ellipse, etc. Furthermore, the size of connecting hole 40 may be any size that allows electronic component 20 to fit inside connecting hole 40.

[0023] (Circuit side terminal) On one side of the flexible substrate 10 on which the electronic component 20 is mounted by solder bonding, at least a circuit and a circuit side terminal 80 (hereinafter, the circuit and the circuit side terminal 80 are collectively referred to as wiring) are formed at the end of the circuit. The wiring is made of one or more conductive materials selected from the group consisting of metallic materials such as gold, silver, copper, aluminum, nickel, and chromium, conductive polymers, and conductive carbon. The wiring can be formed by one or more methods selected from the group consisting of screen printing, inkjet printing, gravure offset printing, flexographic printing, etching, metal vapor deposition, plating, silver halide, etc. Among these, forming the wiring by printing a conductive ink allows for inexpensive and easy mass production. Mass production can also be inexpensive and easy by forming a plating resist by printing or other means and then plating, or by printing a plating seed layer and then plating.

[0024] Furthermore, the ends of the circuit have connection terminals for connecting to a power source or a control device. The power source is not particularly limited, and batteries, household power sources, vehicles, etc. can be used as the power source. For example, the battery can be a dry cell or a lithium ion battery. In particular, the use of a lithium ion battery is preferable because the power source can be repeatedly used by charging. Furthermore, when a solar cell is mounted as the electronic component 20, the solar cell can be used as the power source. In the present invention, a power source such as a battery is incorporated, and the product can be developed further including a control device and a control program for displaying necessary information such as characters and symbols.

[0025] The width of the wiring, particularly the circuit, is preferably 0.01 mm or more and 3.0 mm or less. If the wiring width is less than 0.01 mm, it may be difficult to create the wiring, and when the mounting structure (I) (mounting structure 100) is deformed, the wiring may not be able to withstand the generated stress and may break. If the wiring width exceeds 3.0 mm, when a transparent flexible substrate 10 is used, the wiring may be noticeable and may impair the design. The wiring width is more preferably 0.03 mm or more, and even more preferably 0.1 mm or more. Furthermore, it is more preferably 2 mm or less, and even more preferably 1 mm or less.

[0026] The wiring, especially the circuit, preferably has a thickness of 0.001 mm or more and 0.3 mm or less. In the mounting structure (I) (mounting structure 100), the portions where the electronic components 20 are soldered are rigid and inflexible, while the portions where the electronic components 20 are not soldered bend and exhibit flexibility. When the mounting structure (I) (mounting structure 100) is bent, stress is applied to the portions where the electronic components 20 are soldered. Therefore, if the wiring thickness is less than 0.001 mm, the wiring may not be able to withstand the generated stress when the mounting structure (I) (mounting structure 100) is deformed, resulting in peeling or breakage between the flexible substrate 10 and the wiring near the soldered portions of the electronic components 20. On the other hand, if the wiring thickness exceeds 0.3 mm, the wiring may become too rigid, potentially reducing the flexibility of the mounting structure (I) (mounting structure 100). The wiring thickness is more preferably 0.2 mm or less, even more preferably 0.1 mm or less, even more preferably 0.08 mm or less, and most preferably 0.06 mm or less. Moreover, it is more preferably 0.01 mm or more, and even more preferably 0.02 mm or more.

[0027] (Removable adhesive layer) The mounting structure (I) (mounting structure 100) has a removable adhesive layer 50 on the other side of its connecting region 30. Silicone-based, urethane resin-based, polyolefin resin-based, acrylic resin-based, and other removable adhesives can be used without any particular limitations. As will be described in detail below, when the mounting structures (I) (mounting structures 100) having the removable adhesive layer 50 are connected to form a connected structure, the electronic components are less likely to move within the connecting holes, thereby preventing the arrangement of the electronic components from becoming distorted between the mounting structures (I) (mounting structures 100) that make up the connected structure. The thickness of the removable adhesive layer 50 is not particularly limited as long as it has sufficient adhesive strength, and is, for example, approximately 1 μm to 50 μm.

[0028] (Conductive pad) The mounting structure (I) (mounting structure 100) has a conductive pad 60 on the other surface of the flexible substrate 10 thereof. The conductive pad 60 is formed of a metal material such as gold, silver, copper, aluminum, nickel, or chromium. The conductive pad 60 can be formed by a known method, similar to the wiring. The conductive pad 60 is sized to accommodate one or more circuit terminals 80 located on the opposite side of the flexible substrate 10, and preferably accommodates multiple circuit terminals 80 soldered to one electronic component 20. The conductive pad 60 may be circular, polygonal, or other shapes, such as a circle with a diameter of 3 mm. The thickness of the conductive pad 60, like the wiring, is preferably 0.001 mm or more and 0.3 mm or less, more preferably 0.2 mm or less, even more preferably 0.1 mm or less, even more preferably 0.08 mm or less, and most preferably 0.06 mm or less. Furthermore, the thickness is preferably 0.01 mm or more, and even more preferably 0.02 mm or more.

[0029] (Implementation method) The electronic component 20 is mounted on the circuit-side terminals 80 of the flexible substrate 10 by soldering. There are no particular limitations on the means for soldering the electronic component 20 onto one side of the flexible substrate 10. It is sufficient that the electronic component 20 is placed on the circuit-side terminals 80 via solder 70, and heated in this state to melt the solder 70, thereby soldering the circuit-side terminals 80 and the electronic component-side terminals 21. The means can be determined appropriately taking into consideration the physical properties of the solder used, such as the melting point, the heat resistance of the flexible substrate 10 and the electronic component 20, workability, etc. There are no particular limitations on the type of solder 70. In the present invention, it is preferable to use lead-free solder from the viewpoint of environmental considerations, etc. For example, solders ranging from high-temperature solders (SnAgCu solders, melting point of about 220°C, etc.) to low-temperature solders (SnBi solders, melting point of about 140°C, etc.) can be used.

[0030] As a means for soldering, for example, solder flow, solder reflow, soldering using electromagnetic induction heating technology (IH technology), or the like can be used. In particular, when joining a large number of electronic components 20, workability can be improved by using a heat-resistant material such as polyimide resin as the flexible substrate 10 and using means such as solder reflow. Furthermore, when a material that does not have very high heat resistance, such as polyethylene terephthalate resin (PET resin), is used as the flexible substrate 10, soldering means using IH technology can be used. Soldering means using IH technology (soldering means using electromagnetic induction heating) generates Joule heat by passing an eddy current through a conductive material, and can cause the conductive material to self-heat.

[0031] As a soldering means using the IH technology, for example, the means described in Patent Document 1 can be used. In the mounting structure (I) (mounting structure 100), the conductive pad 60 provided on the other side of the flexible substrate 10 has a larger volume than the circuit-side terminals 80, the solder 70, etc., and therefore generates a large amount of heat due to electromagnetic induction heating. Heat generated in the conductive pad 60 by electromagnetic induction heating is transferred to the solder 70 through the flexible substrate 10 and the circuit-side terminals 80, thereby efficiently heating and melting the solder 70 and soldering the electronic component 20. At this time, the heat generated in the conductive pad 60 by electromagnetic induction heating is quickly transferred to the solder 70, which has high thermal conductivity, and the temperature rise of the flexible substrate 10 is suppressed, so that the flexible substrate 10 can be made of a non-heat-resistant material. By providing the conductive pad 60, the heat generated by IH (electromagnetic induction heating) can be increased, and the temperature can be particularly raised in the area where the conductive pad 60 is formed, making it possible to perform solder bonding more reliably. In particular, when a material with low heat resistance is used for the flexible substrate 10, providing the conductive pad 60 makes it possible to reliably solder the electronic component 20 onto the circuit-side terminal 80 by IH technology, and it is possible to easily obtain a mounting structure (I) (mounting structure 100) on which the electronic component 20 is mounted.

[0032] Even if the flexible substrate 1 does not have a conductive pad 60 on the other side, solder bonding can be achieved by increasing the heating time, increasing the current, reducing the resistance, etc., using heat generated inside the circuit side terminals 80, solder 70, etc. by IH (electromagnetic induction heating). Furthermore, if the flexible substrate 10 and the electronic component 20 are heat resistant, they can be soldered together by heating the entire assembly using a reflow furnace or the like.

[0033] <Features of the mounting structure of the first embodiment example> The mounting structure 100, which is a first embodiment of the mounting structure (I) of the present invention, is flexible. For example, the mounting structure 100 can be wound around a cylinder with a diameter of 1 cm or more. Here, being capable of being wound means that even after being wound around a cylinder, damage to the mounting structure 100, such as breakage of the circuit or peeling of the electronic component 20, does not occur. In the present invention, it is possible to wrap it around a cylinder with a diameter of 1 cm or more, for example, a diameter of 10 cm or more. It is also possible to wrap it around a corrugated plate or the like with a series of arcs with a diameter of 1 cm or more.

[0034] <Concatenated structure> Fig. 3 is a schematic diagram of a connection structure 110 in which mounting structures 100A and 100B are connected, which is a first embodiment of the mounting structure (I) of the present invention, Fig. 4 is a partial cross-sectional view taken along the line A-A' in Fig. 3, and Fig. 5 is an enlarged perspective view of the connection portion. Below, the members of the first and second mounting structures 100A and 100B will be described, each designated by A and B. Note that the connection structure 110 shown in Figs. 3 to 5 is an example configuration, and the connection structure of the present invention is not limited to this example configuration; for example, the number of connected mounting structures (I) (mounting structures 100) is not limited to two. The connection structure 110 connects a first mounting structure 100A and a second mounting structure 100B, which have the same configuration. Specifically, the left two rows of electronic components 20B of the second mounting structure 100B shown in FIG. 3 are fitted into the connection holes 40A of the first mounting structure 100A, thereby connecting the first and second mounting structures.

[0035] In the mounting structure 100A, the connecting holes 40A are formed at positions that form the same square lattice as the electronic components 20A. By fitting the electronic components 20B of the second mounting structure 100B into the connecting holes 40A of this first mounting structure 100A, the electronic components 20A of the first mounting structure and the electronic components 20B of the second mounting structure are arranged in the same square lattice pattern. Furthermore, because the first mounting structure 100A and the second mounting structure 100B are bonded by the removable adhesive layer 50A, the arrangement of the electronic components 20A and 20B between the mounting structures 100A and 100B is less likely to be disrupted. Furthermore, if a failure occurs in the electronic component 20A of the mounting structure 100A, only the mounting structure 100A with the failure needs to be replaced, resulting in excellent maintainability.

[0036] <Installation method> In the connection structure 110, the flexible substrates 10A, 10B of the respective mounting structures 100A, 100B are thin and flexible, so that the steps at the connection points are small, and even after connection, the connection structure has the same flexibility as a single unconnected mounting structure (I), and can be handled as if it were a single mounting structure formed on a single large flexible substrate. The connection structure 110 can be installed not only on flat objects such as walls and glass plates, but also on curved objects such as pillars.

[0037] There are no particular limitations on the installation method of the connected structure 110, but because it is very lightweight, it can be installed, for example, by providing a double-sided adhesive sheet on one or the other side of the flexible substrate 10 and attaching this double-sided adhesive sheet to the object. There are no particular limitations on the material of the double-sided adhesive sheet as long as it has adhesive properties, and silicone-based, urethane resin-based, polyolefin resin-based, acrylic resin-based, rubber-based, etc. can be used. Among these, a removable adhesive that can be peeled off after adhesion and re-adhered is preferred.

[0038] The double-sided adhesive sheet can be provided over the entire surface of the connection structure, or can be provided partially. When the double-sided adhesive sheet is provided partially, it is preferable to provide it so as to straddle the edge of the connection region, since this can prevent the connected mounting structures (I) from shifting. When the double-sided adhesive sheet is provided on the side where the electronic components are provided, a double-sided adhesive sheet having holes or recesses corresponding to the positions of the electronic components can be used, and the electronic components can be attached to the double-sided adhesive sheet so that they fit into the holes or recesses. Double-sided adhesive sheets with holes can be made using known types such as punched adhesive sheets, and double-sided adhesive sheets with recesses can be obtained by attaching a double-sided adhesive sheet with holes to a double-sided adhesive sheet without holes to cover the holes. When the double-sided adhesive sheet is provided on the side where the electronic components are provided, the thickness of the double-sided adhesive sheet is preferably at least 0.5 mm thicker than the height of the electronic components 20, more preferably at least 1 mm thicker, and even more preferably at least 2 mm thicker. By making the double-sided adhesive sheet at least 0.5 mm thicker than the height of the electronic components 20, even if the flexible substrate 10 is pressed against the object by contact or the like after the connection structure 110 is attached to the object, damage to the electronic components 20 due to contact with the object can be prevented. Furthermore, using an elastic adhesive can further prevent contact between the electronic components 20 and the object.

[0039] <Second embodiment example> A schematic diagram of a mounting structure 200 according to a second embodiment of the present invention is shown in FIG. 6, and a partial cross-sectional view taken along the line AA' in FIG. 6 is shown in FIG. The mounting structure 200, which is a second embodiment example, has a connection region 30 at the end of each of the four sides of the flexible substrate 10, the connection region 30 having a width approximately equal to the width of one row of the arranged electronic components 20, and has removable adhesive layers 50 on both sides of the connection region 30, and has the same configuration as the mounting structure 100, which is a first embodiment example.

[0040] The mounting structure 200 can be connected to other mounting structures 200 at all sides, allowing for a high degree of freedom in connection, and allowing for connected structures of various shapes and sizes. The mounting structure 200 can be connected to other mounting structures 200 on either the side where the electronic components 20 are provided or the other side to form a connected structure. The mounting structure 200 has removable adhesive layers 50 on both sides of the connection region 30, and can be bonded to other mounting structures 200 on either the side where the flexible substrate 20 is provided or the other side, thereby preventing misalignment of the arrangement of electronic components between the mounting structures 200 that make up the connected structure. Note that the removable adhesive layer 50 can also be provided on only one side or the other side of the connection region.

[0041] <Other embodiment examples of the mounting structure (I)> In the mounting structure (I) of the present invention, the shape of the flexible substrate is not limited to a quadrangle. For example, by forming the flexible substrate into a shape that can be laid out without gaps on a plane (a shape that allows plane tessellation), the mounting structure can be connected to form a plane without gaps, allowing for unlimited size. There are countless shapes that can be tessellated, but any triangle, any rectangle, a regular hexagon, a parallelepiped, and the 15 types of pentagons that have been discovered so far that can be tessellated are preferred because they have straight sides, are easy to cut, and are available at low cost.

[0042] In the connected structure of the present invention, the shapes of the connected mounting structures (I) may be the same or different. For example, by connecting mounting structures (I) of different shapes, a connected structure with a complex shape such as a company mark or character can be obtained. The shape of the connection structure of the present invention is not limited to a planar shape, but can also be three-dimensional. For example, by connecting mounting structures (I) that are either equilateral triangles, squares, or regular hexagons, a regular polyhedron-shaped connection structure can be obtained. Furthermore, for example, by combining 20 regular hexagonal mounting structures (I) and 12 regular pentagonal mounting structures (I), a connection structure with a shape closer to a sphere, such as a truncated icosahedron (the so-called soccer ball shape), can be obtained.

[0043] [Implementation Structure (II)] <Example of Implementation> FIG. 8 shows a schematic diagram of a mounting structure 300 according to an embodiment of the present invention, and FIG. 9 shows a partial cross-sectional view taken along the line AA' in FIG. The mounting structure 300 includes an electronic device 500 having a plurality of electronic components 20 solder-bonded to one side of a flexible substrate 10, and a double-sided adhesive sheet 600 having holes 610 corresponding to at least some of the electronic components 20.

[0044] (Electronic Devices) The electronic device 500 has a plurality of electronic components 20 mounted on one surface of a rectangular flexible substrate 10 by solder bonding. -Electronic Components- The type of electronic component 20 is not particularly limited and can be selected appropriately depending on the application of the mounting structure 300, and two or more different types can also be mounted. The mounting structure (II) (mounting structure 300) in which light-emitting elements such as LEDs and ELs are mounted as electronic components can be used as a sheet-like display. For example, the mounting structure (II) (mounting structure 300) in which full-color LEDs with built-in control units (hereinafter also referred to as LED elements) are mounted functions as a full-color display device because signals sent to each LED element can be independently controlled from an external main control unit to make each LED element emit or extinguish light in a desired color. The mounting structure (II) (mounting structure 300) that mounts sensors such as temperature, pressure, electric field, magnetic, and light sensors as electronic components can be used as a sheet-like sensor. Also, by alternately arranging two or more types of sensors, such as temperature sensors and pressure sensors, it is possible to obtain in-plane distribution information of two or more different types of measurement data with a single sheet-like sensor. The mounting structure (II) (mounting structure 300) in which solar cells are mounted as electronic components can be a sheet-shaped solar cell. Since the mounting structure (II) (mounting structure 300) of the present invention is flexible, this sheet-shaped solar cell can be installed on a curved surface.

[0045] The electronic components 20 are arranged in a square lattice pattern on one surface of the flexible substrate 10. The arrangement of the electronic components 20 is not particularly limited, and they can be arranged at a constant pitch on one surface of the flexible substrate 10, or they can be arranged in any arrangement on one surface of the flexible substrate 10. The arrangement of the electronic components 20 is preferably a square lattice pattern or a regular triangular lattice pattern, since this allows the electronic components 20 to be arranged at equal intervals and with high density. The number of electronic components 20 is not particularly limited and can be determined appropriately depending on the density of electronic components 20 desired in the mounting structure (II) (mounting structure 300). For example, the number of electronic components 20 can be set to 1 / 100 cm. 2 ~4000 pieces / 100cm 2 The number of electronic components 20 is preferably 30 per 100 cm. 2 ~3000 pieces / 100cm 2 , more preferably 60 pieces / 100cm 2 ~3000 pieces / 100cm 2 , and more preferably 80 pieces / 100cm 2 ~2500 pieces / 100cm 2 It can be said that:

[0046] The shape of electronic component 20 is not limited to the rectangular shape shown in Fig. 8, and examples thereof include a circle, a polygon, an ellipse, etc. Furthermore, the size of electronic component 20 is not particularly limited, but in order to maintain flexibility as mounting structure (II) (mounting structure 300), for example, it is preferably 5 mm or less × 5 mm or less in plan view, more preferably 3 mm or less × 3 mm or less, and even more preferably 2 mm or less × 2 mm or less. -Flexible base material- The flexible substrate 10 in the mounting structure (II) is made of an insulating material. For example, the flexible substrates listed in the first embodiment of the mounting structure (I) can be used. In particular, it is preferable to have a resin film, as this makes it easy to impart the desired physical properties. Examples of resins that can be used to form the resin film include, without particular limitation, polyester resins, polyamideimide resins, polyimide resins, polyamide resins, polyether ether ketone resins, polysulfone resins, polyphenylene sulfide resins, polysulfone resins, polyethersulfone resins, fluororesins, ABS resins, polyphenylene oxide resins, acrylic resins, polycarbonate resins, polybutadiene resins, polyurethane resins, polyolefin resins, polyvinyl chloride resins, and polystyrene resins. The resin may also be a mixture of these resins, and may contain functional materials such as colorants, ultraviolet absorbers, infrared reflective materials, and light scattering particles, as required. Furthermore, the material may be a laminate formed by combining any of these resin films, papers, and cloths.

[0047] The thickness of the flexible substrate 10 is not particularly limited as long as it has flexibility, and may be, for example, 1 μm to 5 mm. From the viewpoint of strength and flexibility, the thickness is preferably 10 μm to 3 mm, more preferably 20 μm to 1 mm. The optical properties of the flexible substrate 10 are not particularly limited and may be any of colorless and transparent, colored and transparent, translucent, and opaque, and can be appropriately selected depending on the application and installation location of the mounting structure (II) (mounting structure 300). The shape of the flexible substrate 10 is not particularly limited, and may be polygonal or circular. In addition, the flexible substrate 10 may have a three-dimensional structure by combining the same or different shapes.

[0048] -wiring- On one side of the flexible substrate 10 on which the electronic component 20 is mounted by solder bonding, at least a circuit and a circuit side terminal 80 (hereinafter, the circuit and the circuit side terminal are collectively referred to as wiring) are formed at the end of the circuit. The wiring in the mounting structure (II) (mounting structure 300) is composed of one or more conductive materials selected from the group consisting of, for example, metal-based materials such as gold, silver, copper, aluminum, nickel, and chromium, conductive polymers, and conductive carbon. Furthermore, the wiring can be formed by one or more methods selected from the group consisting of, for example, screen printing, inkjet printing, gravure offset printing, flexographic printing, etching, metal vapor deposition, plating, silver salt, and the like. Among these, forming the wiring by printing a conductive ink allows for inexpensive and easy mass production. Furthermore, mass production can also be inexpensive and easy by forming a plating resist by printing or other means and then plating, or by printing a plating seed layer and then plating.

[0049] The ends of the circuit have connection terminals for connecting to a power source or a control device. The power source is not particularly limited, and batteries, household power sources, vehicles, etc. can be used as the power source. For example, the battery can be a dry cell or a lithium ion battery. In particular, the use of a lithium ion battery is preferable because the power source can be repeatedly used by charging. Furthermore, when a solar cell is mounted as the electronic component 20, the solar cell can be used as the power source. In the present invention, a power source such as a battery is incorporated, and the product can be developed further including a control device and a control program for displaying necessary information such as characters and symbols.

[0050] The width of the wiring, particularly the circuit, is preferably 0.01 mm or more and 3.0 mm or less. If the wiring width is less than 0.01 mm, it may be difficult to create the wiring, and when the mounting structure (II) (mounting structure 300) is deformed, the wiring may not be able to withstand the generated stress and may break. If the wiring width exceeds 3.0 mm, when a transparent flexible substrate 10 is used, the wiring may be noticeable and may impair the design. The wiring width is more preferably 0.03 mm or more, and even more preferably 0.1 mm or more. Furthermore, it is more preferably 2 mm or less, and even more preferably 1 mm or less.

[0051] The wiring, especially the circuit, preferably has a thickness of 0.001 mm or more and 0.3 mm or less. In the mounting structure (II) (mounting structure 300), the portions where the electronic components 20 are soldered are rigid and inflexible, while the portions where the electronic components 20 are not soldered bend and exhibit flexibility. When the mounting structure (II) (mounting structure 300) is bent, stress is applied to the portions where the electronic components 20 are soldered. Therefore, if the wiring thickness is less than 0.001 mm, the wiring may not be able to withstand the generated stress when the mounting structure (II) (mounting structure 300) is deformed, resulting in peeling or breakage between the flexible substrate 10 and the wiring near the soldered portions of the electronic components 20. On the other hand, if the wiring thickness exceeds 0.3 mm, the wiring may become too rigid, potentially reducing the flexibility of the mounting structure (II) (mounting structure 300). The wiring thickness is more preferably 0.2 mm or less, even more preferably 0.1 mm or less, even more preferably 0.08 mm or less, and most preferably 0.06 mm or less. Moreover, it is more preferably 0.01 mm or more, and even more preferably 0.02 mm or more.

[0052] -Conductive pad- The mounting structure (II) (mounting structure 300) can be provided with a conductive pad 60 on the other surface of the flexible substrate 10 thereof. The conductive pad 60 is formed of a metal material such as gold, silver, copper, aluminum, nickel, or chromium. The conductive pad 60 can be formed by a known method, similar to the wiring. The conductive pad 60 is sized to accommodate the circuit terminals 80 located on the opposite side of the flexible substrate 10, and preferably accommodates multiple circuit terminals 80 soldered to one electronic component 20. The conductive pad 60 may be circular, polygonal, or other shapes, such as a circle with a diameter of 3 mm. The thickness of the conductive pad 60, like the wiring, is preferably 0.001 mm or more and 0.3 mm or less, more preferably 0.2 mm or less, even more preferably 0.1 mm or less, even more preferably 0.08 mm or less, and most preferably 0.06 mm or less. Furthermore, the thickness is preferably 0.01 mm or more, and even more preferably 0.02 mm or more.

[0053] (Implementation method) The electronic component 20 is mounted on the circuit-side terminals 80 of the flexible substrate 10 by soldering. There are no particular limitations on the means for soldering the electronic component 20 onto one side of the flexible substrate 10. It is sufficient that the electronic component 20 is placed on the circuit-side terminals 80 via solder 70, and heated in this state to melt the solder 70, thereby soldering the circuit-side terminals 80 and the electronic component-side terminals 21. The means can be determined appropriately taking into consideration the physical properties of the solder used, such as the melting point, the heat resistance of the flexible substrate 10 and the electronic component 20, workability, etc. There are no particular limitations on the type of solder 70. In the present invention, it is preferable to use lead-free solder from the viewpoint of environmental considerations, etc. For example, solders ranging from high-temperature solders (SnAgCu solders, melting point of about 220°C, etc.) to low-temperature solders (SnBi solders, melting point of about 140°C, etc.) can be used.

[0054] As a means for soldering, for example, solder flow, solder reflow, soldering using electromagnetic induction heating technology (IH technology), or the like can be used. In particular, when joining a large number of electronic components 20, workability can be improved by using a heat-resistant material such as polyimide resin as the flexible substrate 10 and using means such as solder reflow. Furthermore, when a material that does not have very high heat resistance, such as polyethylene terephthalate resin (PET resin), is used as the flexible substrate 10, soldering means using IH technology can be used. Soldering means using IH technology (soldering means using electromagnetic induction heating) generates Joule heat by passing an eddy current through a conductive material, and can cause the conductive material to self-heat.

[0055] As a soldering means using the IH technology, for example, the means described in Patent Document 1 can be used. In the mounting structure (II) (mounting structure 300), the conductive pad 60 provided on the other side of the flexible substrate 10 has a larger volume than the circuit-side terminals 80, the solder 70, etc., and therefore generates a large amount of heat due to electromagnetic induction heating. The heat generated in the conductive pad 60 by electromagnetic induction heating is transferred to the solder 70 through the flexible substrate 10 and the circuit-side terminals 80, thereby efficiently heating and melting the solder 70 and soldering the electronic component 20. At this time, the heat generated in the conductive pad 60 by electromagnetic induction heating is quickly transferred to the solder 70, which has high thermal conductivity, and the temperature rise of the flexible substrate 10 is suppressed, so that the flexible substrate 10 can be made of a non-heat-resistant material. By providing the conductive pad 60, the heat generated by IH (electromagnetic induction heating) can be increased, and the temperature can be particularly raised in the area where the conductive pad 60 is formed, making it possible to perform solder bonding more reliably. In particular, when a material with low heat resistance is used as the flexible substrate 10, by providing the conductive pad 60, the electronic component 20 can be reliably solder bonded onto the circuit-side terminals 80 by IH technology, and a mounting structure (II) (mounting structure 300) on which the electronic component 20 is mounted can be easily obtained.

[0056] Even if the flexible substrate 10 does not have a conductive pad 60 on the other side, solder bonding can be achieved by increasing the heating time, increasing the current, reducing the resistance, etc., using heat generated inside the circuit side terminals 80 and solder 70 by IH (electromagnetic induction heating). Furthermore, if the flexible substrate 10 and the electronic component 20 are heat resistant, they can be soldered together by heating the entire assembly using a reflow furnace or the like.

[0057] <Double-sided adhesive sheet> The double-sided adhesive sheet 600 has a hole 610 corresponding to at least a part of the electronic component 20 . The material of the double-sided adhesive sheet 600 is not particularly limited as long as it has adhesive properties, and silicone-based, urethane resin-based, polyolefin resin-based, acrylic resin-based, rubber-based, etc. can be used. Among these, a removable adhesive that can be peeled off after adhesion and re-adhered is preferable. The double-sided adhesive sheet 600 can contain functional materials such as colorants, ultraviolet absorbers, infrared reflective materials, and light-scattering particles as needed.

[0058] The double-sided adhesive sheet 600 having holes can be, for example, a known punched adhesive sheet. A punched adhesive sheet can be produced, for example, by forming holes in a double-sided adhesive sheet having release films on both sides thereof by punching, laser processing, or the like. A double-sided adhesive sheet having recesses instead of holes can also be used as the double-sided adhesive sheet of the present invention. A double-sided adhesive sheet having recesses can be obtained by bonding a double-sided adhesive sheet without holes to a double-sided adhesive sheet with holes and covering the holes.

[0059] The double-sided adhesive sheet 600 is attached to one side of the electronic device 500 on which the electronic component 20 is mounted, and the electronic component 20 is accommodated in the hole 610. The shape of the hole 610 is not limited to the circular shape shown in FIG. 8 , and may be, for example, a polygon, an ellipse, or the like. The size of the hole 610 is not particularly limited as long as it can accommodate the electronic component 20. The mounting structure (II) is attached to an object on the side of the double-sided adhesive sheet 600 opposite the electronic device 500, so the thickness of the double-sided adhesive sheet 600 needs to be thicker than the height of the electronic component 20. The mounting structure (II) is lightweight and has a substantially uniform height position on the adhesive surface, so it can be installed simply by attaching the double-sided adhesive sheet 600 to the object. The thickness of the double-sided adhesive sheet 600 is preferably 0.5 mm or more thicker than the height of the electronic component 20, more preferably 1 mm or more thicker, and even more preferably 2 mm or more thicker. By making the double-sided adhesive sheet 600 at least 0.5 mm thicker than the height of the electronic component 20, even if the flexible substrate 10 is pressed against the object by contact or the like after the mounting structure (II) is attached to the object, it is possible to prevent damage to the electronic component 20 due to contact with the object. Furthermore, by using an elastic adhesive, it is possible to further prevent contact between the electronic component 20 and the object.

[0060] <Features of the mounting structure (II)> The mounting structure (II) has flexibility. For example, the mounting structure (II) can be wound around a cylinder with a diameter of 1 cm or more. Here, being able to be wound means that even after being wound around a cylinder, damage to the mounting structure (II), such as breakage of the circuit or peeling of the electronic component 20, does not occur. The mounting structure (II) can be wrapped around a cylinder with a diameter of 1 cm or more, for example, a diameter of 10 cm or more. It can also be wrapped around a corrugated plate or the like with a series of arcs with a diameter of 1 cm or more.

[0061] <Installation method> The mounting structure (II), which is one embodiment, can be installed simply by attaching the double-sided adhesive sheet 600 to an object. Furthermore, the size can be increased by attaching multiple mounting structures (II) in a spread-out manner. In this case, by attaching multiple mounting structures (II) to a single double-sided adhesive sheet, the arrangement of electronic components between adjacent mounting structures (II) can be aligned. By installing in this manner, if a failure or the like occurs in an electronic component of a mounting structure (II), only the failed mounting structure (II) needs to be replaced, which is excellent in terms of maintainability. The object to which the mounting structure (II) is attached is not particularly limited and can be appropriately selected depending on the type of electronic device 500 to be included.

Claims

1. a plurality of electronic components soldered onto one surface of the flexible substrate; the flexible substrate has a connecting region along at least a portion of its periphery; a plurality of mounting structures are connected to each other in the connection region, each mounting structure having a plurality of connection holes formed therein corresponding to the positions at which the electronic components are disposed; A connected mounting structure is an enlarged version of adjacent mounting structures that are connected together by fitting an electronic component of one mounting structure into a connecting hole of the other mounting structure.

2. The interconnected mounting structure of claim 1 , wherein the flexible substrate is one of a triangular, a rectangular, a pentagonal, and a hexagonal shape.

3. The connected mounting structure according to claim 1 or 2, further comprising a removable adhesive layer on at least the other side of the connection region.

4. The coupled mounting structure according to any one of claims 1 to 3, further comprising a double-sided adhesive sheet having a recess or hole corresponding to at least a portion of the electronic component.

5. The linked mounting structure described in claim 4, wherein the double-sided adhesive sheet is removably removable.

6. A linked mounting structure described in any one of claims 1 to 5, wherein the electronic components include one or more of a light-emitting element, a sensor element, and a solar cell.

7. an electronic device comprising a plurality of electronic components solder-bonded to one side of a flexible substrate; a removable double-sided adhesive sheet having a recess or hole corresponding to at least a portion of the electronic component; 1. A mounting structure comprising:

8. The mounting structure according to claim 7 , wherein the electronic component includes at least one of a light emitting element, a sensor element, and a solar cell.

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