Stretchable device

Abstract

The invention relates to a stretchable device. Provided is a stretchable device capable of achieving stabilization of electrical connection between connection terminals. A stretchable device is provided with a stretchable substrate having a first resin layer, a resin base material, an array layer, and a second resin layer stacked in this order, and a flexible printed circuit board electrically connected to a circuit included in the array layer, the resin base material having a plurality of terminal portions disposed apart from each other, the circuit having a plurality of first connection terminals disposed at the terminal portions, and the flexible printed circuit board having a plurality of second connection terminals disposed at the terminal portions. The flexible printed circuit board has a plurality of second connection terminals facing the first connection terminals, and an anisotropic conductive resin layer electrically connecting the first connection terminals and the second connection terminals is provided between the first connection terminals and the second connection terminals. The first resin layer includes a first surface on which the resin base material is provided, and a dummy terminal portion provided on the first surface and disposed around the terminal portion.

Description

Technical Field

[0001] The present invention relates to stretchable devices. Background Art

[0002] The stretchable device comprises: a stretchable substrate having stretchability and flexibility; and a flexible printed substrate for electrically connecting a circuit provided on the stretchable substrate to an external device. In addition, the stretchable substrate comprises: an array layer including the circuit, a resin substrate serving as a substrate of the array layer, and two resin layers sandwiching the circuit and the resin substrate. The resin substrate has a main body portion arranged in a matrix shape, and a hinge portion connecting the main bodies to each other. The shape of the hinge portion is, for example, a meandering shape as shown in Patent Document 1. When a tensile load acts on the stretchable substrate, the hinge portion becomes longer in the tensile direction, and the stretchable substrate is stretched.

[0003] As a circuit included in the array layer, for example, a load detection circuit can be cited. The load detection circuit has a strain gauge arranged at the hinge portion. When the hinge portion is deformed, the resistance value of the strain gauge also changes. Furthermore, the load value acting on the hinge portion (stretchable substrate) can be calculated by detecting the change in the resistance value of the strain gauge.

[0004] The circuit includes a connection terminal and a wiring connecting the connection terminal to the load detection circuit as a structure other than the load detection circuit. The connection terminal is electrically connected to the connection terminal of the flexible printed substrate. In addition, in order to set the connection terminal and wiring of the circuit, the resin substrate has a plurality of terminal portions for arranging the connection terminal and a plurality of connection hinge portions for arranging the wiring. The connection terminal of the circuit of Patent Document 1 is electrically connected to the connection terminal of the flexible printed substrate through an anisotropic conductive resin.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent Application Publication No. 2021-106199 Summary of the invention

[0008] Problems to be solved by the invention

[0009] As shown in the above-mentioned Patent Document 1, the multiple terminal portions of the resin substrate are far away from each other. In other words, there is a recess between each terminal portion. Therefore, if anisotropic conductive resin is arranged between the connecting terminals and each connecting terminal is crimped to the anisotropic conductive resin, the anisotropic conductive resin is easy to move to the recess between each terminal portion. That is, the conductive particles contained in the anisotropic conductive resin are also easy to move to the recess between each terminal portion. If the number of conductive particles moving to the recess increases, the electrical connection between the connecting terminals becomes unstable, which is not ideal.

[0010] An object of the present invention is to provide a stretchable device capable of stabilizing the electrical connection between connection terminals.

[0011] Means for solving problems

[0012] A stretchable device according to one embodiment of the present invention comprises: a stretchable substrate having a first resin layer, a resin substrate, an array layer, and a second resin layer stacked in sequence; and a flexible printed substrate electrically connected to a circuit included in the array layer. The resin substrate has a plurality of terminal portions arranged separately from each other. The circuit has a plurality of first connecting terminals arranged at the terminal portions. The flexible printed substrate has a plurality of second connecting terminals opposite to the first connecting terminals. An anisotropic conductive resin layer electrically connecting the first connecting terminal to the second connecting terminal is provided between the first connecting terminal and the second connecting terminal. The first resin layer has a first surface on which the resin substrate is provided, and a dummy terminal portion provided on the first surface and arranged around the terminal portion. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] Figure 1 Schematic diagram of a stretchable device according to an embodiment.

[0014] Figure 2 This is a diagram schematically showing a cross section of a stretchable substrate according to an embodiment. Specifically, Figure 1 A cross-sectional view obtained by cutting along line II-II.

[0015] Figure 3 This is a plan view of the resin base material disposed on the first surface of the first resin layer according to the first embodiment as viewed from the first thickness direction.

[0016] Figure 4 This is an enlarged view of the main body and hinge portion of the first embodiment.

[0017] Figure 5 This is an enlarged view of the main body and hinge portion on which the tensile load of the first embodiment is applied.

[0018] Figure 6 This is a circuit diagram of a circuit included in the array layer of Embodiment 1.

[0019] Figure 7 for Figure 1 Cross-sectional view along line VII-VII.

[0020] Figure 8 This is a plan view of a state in which a part of the anisotropic conductive resin layer is removed in Embodiment 2 as viewed from the first thickness direction.

[0021] Fig. 9is a cross-sectional view of a stretchable device, specifically, along Figure 8 This is a cross-sectional view of the case cut along line IX-IX.

[0022] Fig.10 It is a plan view of the terminal portion and the anisotropic conductive resin layer of Modification 1 as viewed from the first thickness direction.

[0023] Fig.11 It is a plan view of the terminal portion and the dummy terminal portion of the third embodiment as viewed from the first thickness direction.

[0024] Fig.12 It is a plan view of the terminal portion and the dummy terminal portion of the fourth embodiment as viewed from the first thickness direction.

[0025] Description of Reference Numerals

[0026] 5.5A, 5B Anisotropic conductive resin layer

[0027] 6Conductive particles

[0028] 7-division anisotropic conductive resin layer

[0029] 8 Extension

[0030] 10Resin base material

[0031] 11 Main body

[0032] 12 Hinge

[0033] 13Flexion Department

[0034] 19 hollowing out

[0035] 20 end

[0036] 21 connecting hinge

[0037] 22 1st end part

[0038] 23 2nd end part

[0039] 30 array layers

[0040] 31 Load detection circuit

[0041] 32 strain gauges

[0042] 40 Connection Wiring

[0043] 411st connection terminal

[0044] 42 Wiring

[0045] 501st resin layer

[0046] 51 Page 1

[0047] 60 2nd resin layer

[0048] 70, 70D dummy end

[0049] 71, 71D 1st dummy end

[0050] 72, 72D 2nd dummy end

[0051] 73, 73D 3rd dummy terminal

[0052] 100, 100A, 100C, 100D stretchable devices

[0053] 101, 101A, 101C, 101D stretchable substrate

[0054] 102 Flexible printed circuit board

[0055] 104 2nd connection terminal DETAILED DESCRIPTION

[0056] The method (implementation method) for implementing the stretchable device of the present invention is described in detail with reference to the accompanying drawings. The invention of the present invention is not limited by the contents described in the following embodiments. In addition, the constituent elements described below include contents that can be easily thought of by a person skilled in the art and substantially the same contents. In addition, the constituent elements described below can be appropriately combined. It should be noted that the disclosed content is only an example, and appropriate changes that can be easily thought of by a person skilled in the art to maintain the main purpose of the invention are of course included in the scope of the present invention. With respect to the accompanying drawings, in order to make the description clearer, the width, thickness, shape, etc. of each part are sometimes schematically indicated compared to the actual method, but this is only an example and does not limit the interpretation of the present invention. In addition, in this specification and each figure, for the same constituent elements as those described in the accompanying drawings that have appeared, the same figure mark is sometimes attached and the detailed description is appropriately omitted.

[0057] In addition, in the present specification and claims, when expressing the manner of configuring another structure on a certain structure, the phrase "on / on" is used for simplicity. Unless otherwise specified, this includes both the case where the other structure is configured directly on the certain structure in a manner of being in contact with the certain structure and the case where the other structure is configured above the certain structure with another structure in between.

[0058] (Implementation Method 1)

[0059] Figure 1 Schematic diagram of a stretchable device according to an embodiment of the present invention. Figure 1As shown, the stretchable device 100 includes a stretchable substrate 101 and a flexible printed substrate 102. The stretchable substrate 101 and the flexible printed substrate 102 are each formed in a flat plate shape. The stretchable substrate 101 has a front surface 1 and a back surface 2 ( Figure 1 See Figure 2 ).

[0060] The stretchable substrate 101 and the flexible printed substrate 102 are formed into a rectangular (quadrilateral) shape in plan view. One end 102a of the flexible printed substrate 102 is formed through the anisotropic conductive resin layer 5 (see Figure 7 ) is bonded to the stretchable substrate 101. Thus, the stretchable device 100 is long in the direction in which the stretchable substrate 101 and the flexible printed substrate 102 are arranged.

[0061] Hereinafter, the direction parallel to the surface 1 and in which the stretchable substrate 101 and the flexible printed substrate 102 are arranged is referred to as the long side direction. In addition, regarding the long side direction, the direction in which the stretchable substrate 101 is arranged when viewed from the flexible printed substrate 102 is referred to as the first long side direction X1, and the direction opposite to the first long side direction X1 is referred to as the second long side direction X2. In addition, the direction parallel to the surface 1 and intersecting the long side direction is referred to as the intersecting direction.

[0062] Figure 2 This is a diagram schematically showing a cross section of a stretchable substrate according to an embodiment. Specifically, Figure 1 The cross-sectional view taken along the II-II line. Figure 2 As shown, the stretchable substrate 101 includes a first resin layer 50 , a resin base material 10 , an array layer 30 , and a second resin layer 60 which are stacked in this order.

[0063] Hereinafter, the direction in which the first resin layer 50, the resin base material 10, the array layer 30, and the second resin layer 60 are stacked is referred to as the thickness direction. In addition, regarding the thickness direction, the direction in which the second resin layer 60 is arranged when viewed from the first resin layer 50 is referred to as the first thickness direction Z1, and the opposite direction to the first thickness direction Z1 is referred to as the second thickness direction Z2. Observing the stretchable substrate 101 from the first thickness direction Z1 is referred to as a top view. In addition, regarding the cross direction, when the stretchable substrate 101 is viewed from above, the direction arranged on the right side is referred to as the first cross direction Y1, and the direction arranged on the left side is referred to as the second cross direction Y2.

[0064] The first resin layer 50 and the second resin layer 60 are formed of resin and have insulation, stretchability and flexibility. As the resin used for the first resin layer 50 and the second resin layer 60, polyimide can be cited. It should be noted that the first resin layer 50 and the second resin layer 60 of the present invention are not limited to polyimide, and can also be acrylic resin, epoxy resin, urethane resin, etc., without particular limitation.

[0065] The first resin layer 50 and the second resin layer 60 extend in the longitudinal direction and the cross direction, respectively, and are formed into a plate shape. The surface of the first resin layer 50 in the second thickness direction Z2 constitutes the back surface 2 of the stretchable substrate 101. The first resin layer 50 has a first surface 51 facing the first thickness direction Z1. The resin base material 10 is laminated on the first surface 51.

[0066] The surface of the second resin layer 60 in the first thickness direction Z1 constitutes the surface 1 of the stretchable substrate 101. The surface 61 of the second resin layer 60 in the second thickness direction Z2 covers the array layer 30 from the first thickness direction Z1. A frame portion 62 is provided at the end in the long side direction and the end in the cross direction of the second resin layer 60, which protrudes further in the second thickness direction Z2 than the surface 61. The frame portion 62 is annular in a plan view, and surrounds the outer peripheral side of the resin substrate 10 and the array layer 30. The surface of the frame portion 62 in the second thickness direction is bonded to the first surface 51 of the first resin layer 50. Therefore, the first resin layer 50 and the second resin layer 60 cooperate with each other to form a housing for accommodating the resin substrate 10 and the array layer 30.

[0067] Figure 3 This is a plan view of the resin substrate disposed on the first surface of the first resin layer according to Embodiment 1 as viewed from the first thickness direction. Figure 3 In the figure, in order to make the resin substrate 10 easier to see, the resin substrate 10 is filled with hatching. The resin substrate 10 is bonded to the first surface 51 of the first resin layer 50. The resin substrate 10 has stretchability, flexibility and insulation. The resin substrate 10 is formed of a resin material such as polyimide.

[0068] The resin substrate 10 includes: a plurality of main bodies 11, a plurality of hinges 12 extending in a meandering manner, a plurality of terminal portions 20 having a rectangular shape in a plan view, and a connecting hinge portion 21 extending in a meandering manner from the terminal portions 20. The terminal portions 20 and the connecting hinge portion 21 are arranged at the end of the first surface 51 in the second longitudinal direction X2 (see Figure 1 On the other hand, the main body 11 and the hinge 12 are arranged along the first long side direction X1 from the end of the first surface 51 in the second long side direction X2 (see Figure 1 The range enclosed by the dotted line B).

[0069] Figure 4This is an enlarged view of the main body and hinge of Embodiment 1. The main body 11 is quadrilateral (square) in a plan view. The main body 11 is configured in such a way that the four corners point in the long side direction and the cross direction. A plurality of main bodies 11 are arranged in the long side direction and the cross direction and are separated from each other. It should be noted that in the present invention, the shape of the main body 11 in a plan view is not limited to a quadrilateral, but may also be a circle or other polygons.

[0070] like Figure 3 As shown in FIG. 1 , the hinge 12 includes a longitudinal hinge 12A extending in the longitudinal direction and a transverse hinge 12B extending in the cross direction. When viewed from above, if the longitudinal hinge 12A is rotated 90°, it will have the same shape as the transverse hinge 12B. Therefore, in the following description of the hinge 12, the longitudinal hinge 12A will be used as a representative example, and the description of the transverse hinge 12B will be omitted.

[0071] like Figure 4 As shown, the longitudinal hinge portion 12A has four bending portions 13, which extend in a winding manner in the long side direction. Each bending portion 13 of this embodiment is in an arc shape. It should be noted that the bending portion of the present invention may not be in an arc shape, but may be formed in an angular shape. In addition, the number of the bending portions is not limited to four.

[0072] The four curved portions 13 are the first arc portion 14, the second arc portion 15, the third arc portion 16, and the fourth arc portion 17, which are arranged in order from the second longitudinal direction X2. The first arc portion 14 and the fourth arc portion 17 are in the shape of a quarter circle and are bent at 90 degrees. The second arc portion 15 and the third arc portion 16 are in the shape of a semicircle and are bent at 180 degrees.

[0073] Figure 5 This is an enlarged view of the main body and hinge part of the embodiment 1 where the tensile load acts. Figure 5 As shown, when the tensile load in the long side direction (see Figure 5 When the longitudinal hinge 12A is acted on by the arrow C) of the longitudinal hinge 12A, the first arc portion 14, the second arc portion 15, the third arc portion 16 and the fourth arc portion 17 are deformed in such a way that the curvature becomes smaller. As a result, the distance from one end to the other end of the longitudinal hinge 12A becomes larger, and the main body portions 11 are separated from each other. In addition, although not particularly shown in the figure, when the compressive load in the long side direction acts on the longitudinal hinge 12A, the first arc portion 14, the second arc portion 15, the third arc portion 16 and the fourth arc portion 17 are deformed in such a way that the curvature becomes larger. As a result, the distance from one end to the other end of the longitudinal hinge 12A becomes smaller, and the main body portions 11 are moved closer to each other.

[0074] like Figure 3As shown, the portion surrounded by the four hinge portions 12 arranged in an annular shape (quadrilateral) is a hollow portion 19 that penetrates the resin base material 10 in the thickness direction. That is, the resin base material 10 has a plurality of hollow portions 19.

[0075] like Figure 2 As shown in FIG. 1 , the hollow portion 19 is filled with the second resin layer 60. Therefore, the rigidity of the range overlapping the hollow portion 19 in the stretchable substrate 101 has stretchability and flexibility (stretchability). Therefore, when a load acts on the stretchable substrate 101, the hinge portion 12 is deformed. In addition, the deformation of the main body 11 is reduced, and damage to the functional element (the transistor 36 in this embodiment) stacked on the main body 11 is suppressed.

[0076] It should be noted that the hollow portion 19 of the present embodiment is filled with the second resin layer 60, but the present invention may also be filled with the first resin layer 50. Alternatively, the hollow portion 19 may be filled with each of the first resin layer 50 and the second resin layer 60. Alternatively, the hollow portion 19 may be filled with a resin other than the first resin layer 50 and the second resin layer 60. In addition, the hollow portion 19 may be a space without any material.

[0077] like Figure 3 As shown, the terminal portion 20 is formed into a quadrilateral with four sides in a plan view. In addition, the terminal portion 20 is arranged in a manner that the four sides face the longitudinal direction and the intersecting direction. A plurality of terminal portions 20 are arranged at equal intervals in the intersecting direction.

[0078] The connecting hinge 21 extends in the longitudinal direction. The end of the connecting hinge 21 in the first longitudinal direction X1 is connected to the main body 11. The end of the connecting hinge 21 in the second longitudinal direction X2 is connected to the terminal 20. The connecting hinge 21 has a plurality of bent portions 21a similar to the hinge 12, and extends in a meandering manner in the longitudinal direction.

[0079] The connecting hinges 21 are hollowed out and filled with the second resin layer 60. Therefore, when a load is applied to the stretchable substrate 101, the connecting hinges 21 are also deformed. That is, the end of the stretchable substrate 101 in the second longitudinal direction X2 (see Figure 1 The area enclosed by the dotted line A) also has stretchability and flexibility.

[0080] like Figure 2 As shown in FIG. 1 , an array layer 30 is provided on a surface in the first thickness direction Z1 of the resin substrate 10. The array layer 30 includes a plurality of insulating layers (not shown) stacked in the thickness direction, and a circuit whose insulation from the outside is ensured by the plurality of insulating layers. The circuit of this embodiment includes a load detection circuit 31 (see FIG. Figure 6), and a connection wiring 40 for transmitting the result of the load detection circuit 31 to an external device (see Figure 3 ).like Figure 3 As shown in FIG. 1 , the connection wiring 40 is provided at the terminal portion 20 and the connection hinge portion 21. That is, the connection wiring 40 is arranged at the end portion of the second longitudinal direction X2 of the stretchable substrate 101 (see FIG. 1 ). Figure 1 The load detection circuit 31 is provided in the main body 11 and the hinge 12. Therefore, the load detection circuit 31 is arranged closer to the first longitudinal direction X1 than to the end of the second longitudinal direction X2 of the stretchable substrate 101 (see Figure 1 The range enclosed by the dotted line B).

[0081] Figure 6 FIG. 1 is a circuit diagram of a circuit included in the array layer of Embodiment 1. Figure 6 As shown, the load detection circuit 31 includes a strain gauge 32, a gate line 33, a signal line 34, a power supply line 35, a transistor 36, and a gate line driving circuit 37 (see Figure 1 ), signal line selection circuit 38 (see Figure 1 ), power supply line selection circuit 39 (see Figure 1 ), and driver IC90 (see Figure 1 ).

[0082] like Figure 3 As shown, the strain gauge 32 is arranged at the longitudinal hinge portion 12A and extends along the longitudinal hinge portion 12A. Therefore, when the longitudinal hinge portion 12A is deformed, the strain gauge 32 is also deformed, and the resistance value of the strain gauge 32 changes. It should be noted that, in this embodiment, an example in which the strain gauge 32 is arranged at the longitudinal hinge portion 12A is given, but in the present invention, the strain gauge 32 may also be arranged at the transverse hinge portion 12B.

[0083] In addition, the strain gauges 32 are not arranged on all the longitudinal hinges 12A. In detail, the longitudinal hinges 12A arranged on both sides of the cross direction among the plurality of longitudinal hinges 12A (see Figure 1 The strain gauge 32 is not arranged in the range surrounded by the dotted line B1. In addition, among the plurality of longitudinal hinges 12A, the longitudinal hinge 12A arranged at the end in the second longitudinal direction X2 (see Figure 1 The strain gauge 32 is not arranged in the range surrounded by the dotted lines B2 and B3. Therefore, the strain gauge 32 is arranged only in the longitudinal hinge portion 12A. Figure 1 The longitudinal hinge portion 12A is located within the range surrounded by the dotted line B4. Hereinafter, the region where the strain gauge 32 is disposed is referred to as the detection region B4.

[0084] like Figure 3As shown, the detection area B4 is extended in the cross direction by configuring the gate line 33 across multiple horizontal hinges 12B and multiple main bodies 11. In addition, the signal line 34 and the power supply line 35 are configured across multiple vertical hinges 12A and multiple main bodies 11, so that the detection area B4 extends in the long side direction.

[0085] A transistor 36 is disposed in each main body portion 11 disposed in the detection area B4. Figure 6 As shown, the gate electrode of the transistor 36 is connected to the gate line 33. The drain electrode of the transistor 36 is connected to the power supply line 35. The source electrode of the transistor 36 is connected to the signal line 34 via the strain gauge 32.

[0086] The gate line driving circuit 37 is a circuit for driving the plurality of gate lines 33 based on a control signal from a driving IC (Integrated Circuit) 90. The gate line driving circuit 37 is disposed on the plurality of main body portions 11 and the plurality of hinge portions 12 disposed on both sides of the crossing direction (see Figure 1 The range enclosed by the dotted line B1).

[0087] The signal line selection circuit 38 is a switch circuit that selects a plurality of signal lines 34 sequentially or simultaneously based on a control signal from the driver IC 90. Figure 1 As shown, the signal line selection circuit 38 is arranged in the plurality of main body portions 11 and the plurality of hinge portions 12 arranged at the end portions in the second longitudinal direction X2 (see Figure 1 The range enclosed by the dotted line B2).

[0088] The power supply line selection circuit 39 is a switch circuit that selects a plurality of power supply lines sequentially or simultaneously based on a control signal from the driver IC 90. Figure 1 As shown, the power supply line selection circuit 39 is arranged at the end portion of the plurality of main body portions 11 and the plurality of hinge portions 12 arranged in the second long side direction X2 (see Figure 1 The invention also includes a plurality of main body portions 11 and a plurality of hinge portions 12 (in the range surrounded by the dotted line B3).

[0089] The driver IC 90 is a control device that sends various signals to the gate line driver circuit 37, the signal line selection circuit 38, and the power supply line selection circuit 39 to drive the gate line driver circuit 37, the signal line selection circuit 38, and the power supply line selection circuit 39. In this embodiment, the driver IC 90 is provided on the resin substrate 10 of the stretchable substrate 101. In detail, the driver IC 90 is arranged in one of the plurality of main body portions 11 that is closest to the second long side direction X2 and is located in the first cross direction Y1 (see Figure 1). In addition, the main body 11 provided with the driver IC 90 is formed larger than other main body 11 in a plan view. It should be noted that in the present invention, the driver IC 90 is not limited to the position shown in Embodiment 1. In addition, the driver IC 90 may be provided in an external device instead of being mounted on the stretchable substrate 101.

[0090] An operation example of the load detection circuit 31 is described. Figure 6 As shown, when one gate line 33 selected by the gate line driving circuit 37 is driven, a plurality of transistors 36 in the cross direction connected to the gate line 33 are turned off. In addition, a signal (e.g., a voltage value) is sent to the strain gauge 32 via the transistor 36 from one or more power supply lines 35 selected by the power supply line selection circuit 39.

[0091] When the longitudinal hinge 12A is not deformed, the voltage value of the signal flowing through the strain gauge 32 becomes a predetermined value. On the other hand, when the longitudinal hinge 12A is deformed, the resistance value of the strain gauge 32 changes. That is, the signal flowing through the strain gauge 32 shows a voltage value different from the predetermined value. The signal (detection result) output by the strain gauge 32 flows to the signal line 34. And, the signal (detection result) is sent from the signal line 34 selected by the signal line selection circuit 38 to the connection wiring 40 (see Figure 3 ).

[0092] like Figure 3 As shown, the connection wiring 40 includes a plurality of first connection terminals 41 disposed at the terminal portion 20, and a plurality of wirings 42 disposed at the connection hinge portion 21. The first connection terminal 41 is formed to be rectangular in a plan view. It should be noted that the first connection terminal 41 of the present embodiment is smaller than the terminal portion 20 in a plan view, and the terminal portion 20 is exposed from the periphery of the first connection terminal 41, but in the present invention, the first connection terminal 41 and the terminal portion 20 may also be the same size.

[0093] The wiring 42 extends in the longitudinal direction. A first end portion of the wiring 42 in the longitudinal direction X1 is connected to the load detection circuit 31 . A second end portion of the wiring 42 in the longitudinal direction X2 is connected to the first connection terminal 41 .

[0094] Figure 7 yes Figure 1 The VII-VII line cross-sectional view. Figure 7 As shown in FIG. 1 , an anisotropic conductive resin layer 5 is provided in the first thickness direction Z1 of the first connection terminal 41. The anisotropic conductive resin layer 5 is a resin in which conductive fine particles (hereinafter referred to as conductive particles 6) are dispersed. Figure 3As shown, the length L of the anisotropic conductive resin layer 5 in the plane direction is longer than the length of the first connection terminal 41 and the terminal portion 20 in the plane direction. Therefore, the anisotropic conductive resin layer 5 bulges from the terminal portion 20 in the first longitudinal direction X1 and the second longitudinal direction X2 and adheres to the first surface 51 of the first resin layer 50.

[0095] In addition, the anisotropic conductive resin layer 5 extends in the cross direction. The end of the anisotropic conductive resin layer 5 in the first cross direction Y1 extends further in the first cross direction Y1 than the first connection terminal 41A disposed closest to the first cross direction Y1 among the plurality of first connection terminals 41. In addition, the end of the anisotropic conductive resin layer 5 in the second cross direction Y2 extends further in the second cross direction Y2 than the first connection terminal 41B disposed closest to the second cross direction Y2 among the plurality of first connection terminals 41. Therefore, the anisotropic conductive resin layer 5 is disposed across each of the first connection terminals 41, each of the terminal portions 20, and the periphery of each of the terminal portions 20 (the first surface 51 of the first resin layer 50).

[0096] The flexible printed circuit board 102 is a connection component for electrically connecting the stretchable device 100 to an external device. Figure 1 As shown, the flexible printed circuit board 102 includes a second connection terminal 104 disposed at one end 102 a of the flexible printed circuit board 102 , and a wiring portion 105 extending from the second connection terminal 104 in the second longitudinal direction X2 .

[0097] like Figure 7 As shown, one end 102a of the flexible printed substrate 102 is disposed between the anisotropic conductive resin layer 5 and the second resin layer 60, and is bonded to each of the anisotropic conductive resin layer 5 and the second resin layer 60. The second connection terminal 104 is provided on a surface of the flexible printed substrate 102 in the second thickness direction Z2, and faces the first connection terminal 41.

[0098] In addition, in the method for forming the anisotropic conductive resin layer 5 of the present embodiment, the anisotropic conductive resin layer 5 is applied on each of the first connection terminals 41, each terminal portion 20, and the periphery of each terminal portion 20 (the first surface 51 of the first resin layer 50) in a state where the resin of the anisotropic conductive resin layer 5 is melted. Next, the flexible printed substrate 102 is stacked in the first thickness direction Z1 of the anisotropic conductive resin layer 5, and the flexible printed substrate 102 is pressed in the second thickness direction Z2. Thus, each of the first connection terminals 41, each terminal portion 20, the periphery of each terminal portion 20 (the first surface 51 of the first resin layer 50), and the flexible printed substrate 102 (including the second connection terminal 104) are pressed against the anisotropic conductive resin layer 5. Then, the resin is cured to form the anisotropic conductive resin layer 5.

[0099] Here, when the flexible printed substrate 102 is pressed (pressed), the conductive particles 6 are crushed between the first connection terminal 41 and the second connection terminal 104. The crushed plurality of conductive particles 6 are in contact with each other, forming a conductive path in the thickness direction. The first connection terminal 41 and the second connection terminal 104 are electrically connected through the plurality of conductive particles 6.

[0100] like Figure 3 and Figure 7 As shown, a dummy terminal portion 70 is provided on the first surface 51 of the first resin layer 50. The dummy terminal portion 70 is arranged around the terminal portion 20. The dummy terminal portion 70 is formed of a resin such as polyimide, an inorganic material, or an organic material. The dummy terminal portion 70 of the first embodiment has a rectangular first dummy terminal portion 71 arranged between the terminal portions 20. The size H1 in the thickness direction of the first dummy terminal portion 71 (see Figure 7 ) is the same as the terminal portion 20.

[0101] It should be noted that, assuming that there is no dummy terminal 70, the terminals 20 form a concave portion with the first surface 51 as the bottom surface. Therefore, when the flexible printed substrate 102 is pressed against the anisotropic conductive resin layer 5, the anisotropic conductive resin layer 5 easily moves to the concave portion between the terminals 20 (see Figure 7 arrow D).

[0102] According to the first embodiment described above, the first dummy terminal 71 fills the space between the terminal portions 20. When the flexible printed substrate 102 is crimped to the anisotropic conductive resin layer 5, the anisotropic conductive resin layer 5 is not easily moved between the terminal portions 20. That is, the conductive particles 6 contained in the anisotropic conductive resin layer 5 are prevented from moving between the terminal portions 20. As a result, the reduction of the conductive particles 6 that electrically connect the first connection terminal 41 and the second connection terminal 104 is suppressed. Therefore, the electrical connection between the first connection terminal 41 and the second connection terminal 104 becomes stable.

[0103] In addition, if Figure 7 As shown, the first dummy terminal portion 71 of the first embodiment is separated from the terminal portion 20, and a gap is provided between the first dummy terminal portion 71 and the terminal portion 20. The size H2 of the gap between the first dummy terminal portion 71 and the terminal portion 20 is smaller than the diameter of the conductive particles 6. Based on this, the conductive particles 6 are not easy to move between the first dummy terminal portion 71 and the terminal portion 20. It should be noted that the diameter of the conductive particles 6 is generally 3 μm. Therefore, the gap between the first dummy terminal portion 71 and the terminal portion 20 is preferably less than 3 μm.

[0104] Embodiment 1 has been described above, but the present invention is not limited to the example of embodiment 1. For example, the size H1 of the thickness direction of the dummy terminal portion 70 may be larger or smaller than the terminal portion 20, without particular limitation. Next, other embodiments will be described. In addition, the following description focuses on the differences from embodiment 1.

[0105] (Implementation Method 2)

[0106] Figure 8 This is a plan view of a state in which a part of the anisotropic conductive resin layer is removed in Embodiment 2 as viewed from the first thickness direction. Fig. 9 is a cross-sectional view of a stretchable device, specifically, along Figure 8 The cross-sectional view of the case where the IX-IX line is cut. Figure 8 , Fig. 9 As shown, the stretchable substrate 101A of the stretchable device 100A according to the second embodiment is provided only at the first connection terminal 41 ( Figure 8 See Fig. 9 ) and the first thickness direction Z1 of the terminal portion 20, but not arranged around the terminal portion 20 (the first surface 51 of the first resin layer 50). That is, the anisotropic conductive resin layer 5A of the second embodiment is composed of a plurality of divided anisotropic conductive resin layers 7. It should be noted that in order to facilitate observation, Figure 8 The divided anisotropic conductive resin layer 7 is illustrated in a manner such that the outer periphery of the divided anisotropic conductive resin layer 7 is smaller than the outer periphery of the terminal portion 20 .

[0107] In the method for forming the anisotropic conductive resin layer 5A of the second embodiment, a sheet-shaped anisotropic conductive resin formed by curing the resin is laminated on each of the first connection terminals 41, each of the terminal portions 20, and the periphery of each of the terminal portions 20 (the first surface 51 of the first resin layer 50). It should be noted that the sheet-shaped anisotropic conductive resin is the same size as the anisotropic conductive resin layer 5 of the first embodiment (see Figure 3 ). Next, the portion of the sheet-shaped anisotropic conductive resin that overlaps with the periphery of the terminal portion 20 (the first surface of the first resin layer) in the thickness direction is removed by, for example, laser. Thus, the sheet-shaped anisotropic conductive resin is divided and placed only on the first connection terminal 41 and the terminal portion 20.

[0108] Next, the anisotropic conductive resin is melted, and the flexible printed substrate 102 is pressed from the first thickness direction Z1 of the anisotropic conductive resin. When the resin is further solidified, a plurality of divided anisotropic conductive resin layers 7 are formed. In addition, when the flexible printed substrate 102 is pressed, the conductive particles 6 are crushed between the first connection terminal 41 and the second connection terminal 104. And the plurality of crushed conductive particles 6 are in contact with each other, forming a conductive path in the thickness direction. Thus, the first connection terminal 41 and the second connection terminal 104 are electrically connected.

[0109] As described above, in the second embodiment, when the flexible printed circuit board 102 is pressed against the anisotropic conductive resin layer 5A, the anisotropic conductive resin layer 5A is crushed in the second thickness direction Z2. A portion of the anisotropic conductive resin layer 5A flows from the first connection terminal 41 and the terminal portion 20 to between the terminal portions 20 (see Fig. 9 However, since the terminals 20 are filled with the dummy terminals 70 (first dummy terminals 71), it is difficult for a part of the anisotropic conductive resin layer 5A to move between the terminals 20. Therefore, in the second embodiment, the reduction of the conductive particles 6 that electrically connect the first connection terminal 41 and the second connection terminal 104 is suppressed.

[0110] Fig.10 This is a top view of the end portion and the anisotropic conductive resin layer of the modification example 1 as viewed from the first thickness direction. It should be noted that in the second embodiment, the anisotropic conductive resin layer 5A (a plurality of divided anisotropic conductive resin layers 7) is formed by removing a portion of the sheet-like anisotropic conductive resin by laser or the like, but the present invention is not limited thereto. Fig.10 As shown in FIG. 1 , the anisotropic conductive resin layer 5B of the modification example 1 includes a plurality of divided anisotropic conductive resin layers 7 and an extension portion 8 connecting the divided anisotropic conductive resin layers 7 before being placed on the first connection terminal 41 and the terminal portion 20. When the flexible printed substrate 102 is pressed against the divided anisotropic conductive resin layers 7, the extension portion 8 is not crushed by the flexible printed substrate 102. Therefore, the conductive particles 6 included in the extension portion 8 are separated from each other and do not constitute a conductive path. According to the anisotropic conductive resin layer 5B of the modification example 1, a process of removing by laser or the like is not required.

[0111] (Implementation method 3)

[0112] Fig.11 It is a plan view of the terminal portion and the dummy terminal portion according to Embodiment 3 as viewed from the first thickness direction. A stretchable substrate 101C of a stretchable device 100C according to Embodiment 3 is different from that of Embodiment 1 in that a dummy terminal portion 70C is provided instead of the dummy terminal portion 70 .

[0113] The dummy terminal portion 70C includes a first dummy terminal portion 71 located between the terminal portions, a second dummy terminal portion 72 arranged in the second long side direction X2 (the other side in the long side direction) relative to the terminal portion, and a third dummy terminal portion 73 arranged at the outermost side in the cross direction. The second dummy terminal portion 72 can prevent the anisotropic conductive resin layer 5 stacked on the first connection terminal 41 and the terminal portion 20 from flowing (moving) to the second long side direction X2 side.

[0114] The third dummy terminal portion 73 includes: a third dummy terminal portion 73A, which is arranged in the first cross direction Y1 of the terminal portion 20A arranged closest to the first cross direction Y1 among the plurality of terminal portions; and a third dummy terminal portion 73B, which is arranged in the second cross direction Y2 of the terminal portion 20B arranged closest to the second cross direction Y2 among the plurality of terminal portions. According to the third dummy terminal portion 73A, the anisotropic conductive resin layer 5 stacked on the first connection terminal 41A and the terminal portion 20A arranged closest to the first cross direction Y1 can be suppressed from flowing (moving) to the first cross direction Y1 side. In addition, according to the third dummy terminal portion 73B, the anisotropic conductive resin layer 5 stacked on the first connection terminal 41B and the terminal portion 20B arranged closest to the second cross direction Y2 can be suppressed from flowing (moving) to the second cross direction Y2 side.

[0115] As described above, according to Embodiment 3, more conductive particles are present between the first connection terminal 41 and the second connection terminal 104 than in Embodiments 1 and 2. Therefore, the electrical connection between the first connection terminal 41 and the second connection terminal 104 is further stabilized.

[0116] In the above-mentioned embodiment and modification, an example in which a plurality of terminal portions 20 are arranged in the intersecting direction is described, but the present invention is not limited thereto. In the following embodiment 4, an example in which the arrangement of the terminal portions 20 is changed is described.

[0117] (Implementation 4)

[0118] Fig.12 1 is a plan view of the terminal and dummy terminal of Embodiment 4 as viewed from the first thickness direction. The stretchable substrate 101D of the stretchable device 100D of Embodiment 4 is different from Embodiment 1 in that a plurality of terminal portions 20D are arranged staggered in the long side direction. The terminal portion 20D includes a plurality of first terminal portions 22 arranged at intervals in the cross direction, and a plurality of second terminal portions 23 arranged between the first terminal portions 22. The second terminal portions 23 are arranged in the second long side direction X2 relative to the first terminal portions 22.

[0119] The dummy terminal portion 70D of the fourth embodiment includes a first dummy terminal portion 71D, a second dummy terminal portion 72D, and a third dummy terminal portion 73D. The first dummy terminal portion 71D is disposed between the second terminal portions 23. Therefore, the first dummy terminal portion 71D is disposed in the second long side direction X2 relative to the first terminal portion 22. Therefore, the first dummy terminal portion 71D suppresses the anisotropic conductive resin layer 5 from moving between the second terminal portions 23, and further suppresses the anisotropic conductive resin layer 5 from moving from the first terminal portion 22 to the second long side direction X2.

[0120] The second dummy terminal portion 72D is arranged in the second longitudinal direction X2 with respect to the second terminal portion 23. Therefore, the second dummy terminal portion 72D suppresses the anisotropic conductive resin layer 5 from moving from the second terminal portion 23 in the second longitudinal direction X2.

[0121] There are two third dummy terminal portions 73D. The first third dummy terminal portion 73D is arranged in the first cross direction Y1 of the second terminal portion 23A that is arranged closest to the first cross direction Y1 among the plurality of second terminal portions 23. The second third dummy terminal portion 73D is arranged in the second cross direction Y2 of the terminal portion 20B (which is arranged closest to the second cross direction Y2). Therefore, the anisotropic conductive resin layer 5 is suppressed from moving from the second terminal portion 23A in the first cross direction Y1. In addition, the anisotropic conductive resin layer 5 is suppressed from moving from the second terminal portion 23B in the second cross direction Y2.

[0122] In the above, the embodiment and the modified example are described, and the dummy terminal portion is divided into a plurality of parts, but in the present invention, the plurality of dummy terminal portions described in each embodiment and the modified example may be integrated. In addition, in the embodiment, the circuit included in the array layer 30 is a load detection circuit for measuring the load in the long side direction and the cross direction of the stretchable substrate 101, but the present invention may also be other circuits.

Claims

1. A stretchable device having: A stretchable substrate having a first resin layer, a resin base material, an array layer, and a second resin layer stacked in sequence; and a flexible printed substrate electrically connected to the circuit contained in the array layer, in, The resin substrate has a plurality of terminal portions that are spaced apart from each other. The circuit has a plurality of first connection terminals arranged at the terminal portion, The flexible printed circuit board has a plurality of second connection terminals facing the first connection terminals. An anisotropic conductive resin layer is provided between the first connection terminal and the second connection terminal to electrically connect the first connection terminal and the second connection terminal. The first resin layer comprises: The first surface on which the resin substrate is disposed; and A dummy terminal portion is provided on the first surface and arranged around the terminal portion.

2. The stretchable device according to claim 1, wherein: The resin substrate has a connecting hinge portion extending along the first surface, The end of the connecting hinge portion in the longitudinal direction from which the connecting hinge portion extends is connected to the terminal portion, The plurality of terminal portions are arranged at intervals in a direction parallel to the first surface and intersecting the longitudinal direction. The dummy terminal portion is arranged between the terminal portions adjacent to each other in the intersecting direction.

3. The stretchable device according to claim 2, wherein: The connecting hinge portion is arranged on one side of the long side direction relative to the terminal portion, The dummy terminal portion is arranged on the other side of the terminal portion in the long-side direction.

4. The stretchable device according to claim 1, wherein: The resin substrate has a connecting hinge portion extending along the first surface, The connecting hinge is arranged on one side of the long side direction in which the connecting hinge extends relative to the terminal portion. The end of the connecting hinge portion in the longitudinal direction is connected to the terminal portion, A plurality of said terminal portions have: a plurality of first terminal portions arranged at intervals in a direction parallel to the first surface and intersecting the longitudinal direction; a plurality of second terminal portions, which are arranged between the plurality of first terminal portions; wherein the second terminal portion is arranged on the other side of the long side direction than the first terminal portion, The dummy terminal portion is arranged between the second terminal portions and on the other side in the longitudinal direction with respect to the first terminal portion.

5. The stretchable device according to claim 1, wherein: The anisotropic conductive resin layer is arranged across the first surface, the plurality of terminal portions, and the first connection terminals.

6. The stretchable device according to claim 1, wherein: The anisotropic conductive resin layer is disposed only on the plurality of terminal portions and the first connection terminal.

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