Stretchable device

Abstract

Provided is a stretchable device comprising a stretchable base material, a stretchable wiring provided on the stretchable base material, and an adhesive layer having portions which are separated from and facing each other. The stretchable wiring is located between the portions, of the adhesive layer, separated from and facing each other, when viewed from the thickness direction of the stretchable base material.

Description

stretchable devices

[0001] The present disclosure relates to stretchable devices.

[0002] Stretchable devices in which stretchable wiring is mounted on a stretchable substrate have been known for some time. These stretchable devices can be worn on the human body.

[0003] Patent Literature 1 describes a stretchable device in which an adhesive layer for mounting to a target object is attached to the entire mounting surface of a stretchable substrate. In such a stretchable device, the adhesive layer for mounting is formed over one surface of the stretchable substrate.

[0004] Japanese Patent Application Laid-Open No. 2021-64676

[0005] As in Patent Document 1, when a mounting adhesive layer is formed on the entire surface of a stretchable substrate facing the mounting body, the stretchable substrate is integrated with the mounting adhesive layer. Therefore, the stretchable substrate and the mounting adhesive layer can deform integrally in accordance with the movement of the mounted body. If stress such as tension or twisting is applied to the stretchable wiring arranged on the stretchable substrate in response to such deformation, the resistance value of the stretchable wiring may change, potentially causing errors in the signals transmitted by the stretchable wiring.

[0006] The present disclosure has been made in view of the above-mentioned problems. That is, a main object of the present disclosure is to provide a stretchable device that can suppress a change in the resistance value of a stretchable wiring caused by deformation of the stretchable device.

[0007] In order to achieve the above object, one embodiment of the present disclosure provides a stretchable device comprising: a stretchable substrate; stretchable wiring provided on the stretchable substrate; and an adhesive layer having portions spaced apart and facing each other, wherein, when viewed in the thickness direction of the stretchable substrate, the stretchable wiring is located between the portions of the adhesive layer that are spaced apart and facing each other.

[0008] According to the stretchable device according to an embodiment of the present disclosure, it is possible to suppress a change in the resistance value of the stretchable wiring caused by deformation of the stretchable device.

[0009] FIG. 1 is a top view schematically showing a stretchable device according to a first embodiment of the present disclosure. FIG. 2 is a cross-sectional view taken along line A-A of the stretchable device shown in FIG. 2. FIG. 3 is a schematic top view schematically showing the entire stretchable device according to the first embodiment of the present disclosure. FIG. 4 is a schematic cross-sectional view of a stretchable device according to a first modified example of the first embodiment of the present disclosure. FIG. 5 is a schematic cross-sectional view of a stretchable device according to a second modified example of the first embodiment of the present disclosure. FIG. 6 is a schematic plan view of a stretchable device according to a third modified example of the first embodiment of the present disclosure. FIG. 7 is a top view schematically showing a stretchable device according to a second embodiment of the present disclosure. FIG. 8 is a cross-sectional view taken along line B-B of the stretchable device shown in FIG. 7. FIG. 9 is a schematic cross-sectional view of a stretchable device according to a modified example of the second embodiment of the present disclosure. FIG. 10 is a schematic cross-sectional view of a stretchable device according to a modified example of the second embodiment of the present disclosure.

[0010] Hereinafter, embodiments of the present disclosure will be described in detail with reference to the drawings. In each embodiment, differences from those previously described will be mainly described. In particular, similar effects resulting from similar configurations will not be mentioned in each embodiment. Among the components in the following embodiments, components not recited in independent claims will be described as optional components. Furthermore, the size and size ratios of components shown in the drawings are not necessarily strict. Furthermore, in each figure, substantially identical components are assigned the same reference numerals, and duplicated descriptions may be omitted or simplified.

[0011] As used herein, the terms "cross-sectional view" and "cross-sectional shape" refer to the shape of the stretchable device as viewed from a direction substantially perpendicular to the thickness direction of the stretchable device (in short, the shape of the stretchable device when cut along a plane parallel to the thickness direction of the stretchable device). Furthermore, as used herein, the term "planar view" refers to a sketch of the object as viewed from above or below along the thickness direction of the stretchable device.

[0012] Furthermore, in this specification, "above" an element includes not only the case of contacting the top surface of the element, but also the case of not contacting the top surface of the element. In other words, "above" an element does not only mean above the element, i.e., a position above the element via another object or a position above with a gap, but also a position directly above the element. Furthermore, "above" does not necessarily mean above in the vertical direction. "Above" merely indicates the relative positional relationship of an element.

[0013] [First embodiment] The structure of a stretchable device will be described with reference to Figures 1 and 2. Figure 1 is a top view schematically showing a stretchable device 100 according to a first embodiment of the present disclosure. Figure 2 is a cross-sectional view taken along the line A-A of the stretchable device in Figure 1. Note that cross-sectional views in this specification are cross-sections perpendicular to the stretching direction of a stretchable wire. Actual comparisons can also be confirmed using the above cross-sectional view at any position of a stretchable wire stretching in one direction.

[0014] In the stretchable device 100, a stretchable wiring 20 is routed on the main surface of a stretchable substrate 10. The shape of the stretchable device 100 is not particularly limited. In FIG. 1, the extension direction of the stretchable wiring 20 and the longitudinal direction of the stretchable device 100 coincide, but they do not necessarily have to coincide. Furthermore, in FIG. 1, for clarity, only wiring that extends in a specific direction is depicted, but the stretchable wiring 20 does not have to extend in one direction.

[0015] The stretchable device 100 comprises a stretchable substrate 10 having a first main surface 11 and a second main surface 12 located on the opposite side of the first main surface 11, stretchable wiring 20 provided on the main surface of the stretchable substrate 10, and an adhesive layer 30 that can be attached to an adherend 200 that contributes to mounting the stretchable device 100. In this specification, "upper" refers to the first main surface 11 side in the thickness direction X of the stretchable substrate, and "lower" refers to the second main surface 12 side in the thickness direction X of the stretchable substrate. These directions do not have to coincide with the top and bottom when the stretchable device 100 is in use. Furthermore, in this specification, "outer side" refers to the side that is relatively far from the stretchable substrate 10, and similarly does not have to coincide with the outside when actually in use.

[0016] Furthermore, in this specification, the term "adherend" refers to the object to which the stretchable device is attached, and can also be referred to as an adhesive object, an attached object, an object to be mounted, etc. For example, the adherend can be a living body.

[0017] The arrangement of these components will be described below with reference to Figures 1 and 2. As shown in Figures 1 and 2, an elastic wiring 20 is provided on the first main surface 11 of the elastic substrate, and an adhesive layer 30 is provided on the second main surface 12 side.

[0018] (Stretchable Substrate 10) The stretchable substrate 10 is a sheet-like or film-like stretchable substrate, and is made of, for example, a stretchable resin material. Here, in this specification, "stretchability" simply means the property of being able to expand and contract, and can also be referred to as "stretchability" or "stretchable." More specifically, it refers to the property of being able to expand from a non-stretched state, i.e., a normal state in which no tensile stress is applied, by applying tensile stress, and being able to contract when released from the stretched state. Examples of resin materials include thermoplastic polyurethane. The thickness of the stretchable substrate 10 is not particularly limited, but from the viewpoint of not inhibiting the expansion and contraction of the surface of the adherend 200 when attached to the adherend 200, such as a living body, it is preferably 1 mm or less, more preferably 100 μm or less, and even more preferably 50 μm or less. Furthermore, the thickness of the stretchable substrate is preferably 1 μm or more.

[0019] (Stretchable Wiring 20) The stretchable wiring 20 contains conductive particles and a resin. Examples of the stretchable wiring 20 include a mixture of metal powder such as Ag (silver), Cu (copper), or Ni (nickel) as conductive particles and an elastomer resin such as a silicone resin. The average particle size of the conductive particles is not particularly limited, but is preferably 0.01 μm or more and 10 μm or less. Furthermore, the conductive particles are preferably spherical in shape.

[0020] The thickness of the stretchable wiring 20 is not particularly limited, but is preferably 100 μm or less, and more preferably 50 μm or less. Furthermore, the thickness of the stretchable wiring 20 is preferably 0.01 μm or more. The line width of the stretchable wiring 20 is not particularly limited, but is preferably 0.1 μm or more, and more preferably 10 mm or less. Furthermore, the cross-sectional shape and planar shape of the stretchable wiring, as well as the number, are not particularly limited.

[0021] (Adhesive layer 30) The adhesive layer 30 has adhesiveness that allows the stretchable device 100 to be attached to the adherend 200. The adhesive layer 30 has a substrate-side main surface 31 located on the stretchable substrate 10 side, and an adherend-side main surface 32 located on the adherend 200 side. The stretchable device 100 is mounted so as to be bonded to the adherend 200 at the adherend-side main surface 32 of the adhesive layer 30, and the adherend-side main surface 32 can also be referred to as an attachment surface, a sticking surface, a mounting surface, or the like. It is preferable that the adhesive layer 30 has adhesiveness on both main surfaces. That is, the adhesive layer 30 may have adhesiveness not only on the attachment surface 32 to the adherend 200, but also on the substrate-side main surface 31.

[0022] The adherend-side main surface 32 of the adhesive layer can be attached to a living body. Therefore, various adhesives can be used for the adhesive layer 30, without particular limitation, as long as they are mild to the skin, have sufficient pressure-sensitive adhesive properties, and can be easily peeled off from the skin after use. Furthermore, from the viewpoint of adaptability to the shape and movement of the living body surface, it is preferable that the adhesive layer 30 have excellent elasticity and flexibility. Although merely exemplary, examples of materials for the adhesive layer 30 include synthetic rubber-based adhesives, acrylic-based adhesives, urethane-based adhesives, natural rubber-based adhesives, silicone-based adhesives, etc., with synthetic rubber-based adhesives being more preferred.

[0023] (Characteristic Parts of the First Embodiment) Based on the main components of the stretchable device described above, the characteristic parts of the first embodiment will be described below. As shown in FIGS. 1 and 2 , in the stretchable device 100 according to the first embodiment of the present disclosure, one or more adhesive layers 30 that can be attached to an adherend have portions that are spaced apart and facing each other when viewed from the thickness direction X of the stretchable substrate. That is, the stretchable device 100 has one or more adhesive layers 30, and the adhesive layers 30 may be arranged so as to include portions that are spaced apart and facing each other. The adhesive layer 30 does not have to be provided over the entire second main surface 12 side of the stretchable substrate. This can also be interpreted as the stretchable device 100 having a region that includes the adhesive layer 30 and a region that does not include the adhesive layer 30 on the second main surface 12 side of the stretchable substrate.

[0024] When viewed from the thickness direction X of the stretchable substrate, the stretchable wiring 20 is located between portions of the adhesive layer 30 that face each other at a distance. In other words, when viewed from the thickness direction X of the stretchable substrate, the adhesive layer 30 may be arranged so as to have portions that face each other at a distance, sandwiching the stretchable wiring 20 therebetween. In such a structure, when viewed from the thickness direction X of the stretchable substrate, the stretchable wiring 20 is arranged so as to overlap with regions where the adhesive layer 30 is not provided. In other words, the adhesive layer 30 is arranged at a position that does not overlap at least the outer main surface 21 of the stretchable wiring 20 that faces the stretchable substrate 10. This structure can also be interpreted as the stretchable wiring 20 and the adhesive layer 30 being arranged offset from each other when viewed from the thickness direction X of the stretchable substrate. In this specification, the "outer main surface 21 of the stretchable wiring 20 that faces the stretchable substrate 10" means a surface that is located distal to the stretchable substrate 10. For example, as shown in Figure 2, the "outer main surface 21 of the elastic wiring facing the elastic substrate" is the surface located on the opposite side to the main surface of the elastic wiring 20 that faces the elastic substrate 10.

[0025] From another perspective, the stretchable device 100, as shown in Fig. 2, comprises a first overlapping region 51 comprising the adhesive layer 30 and a second overlapping region 52 comprising the stretchable wiring 20. Specifically, the stretchable device 100 comprises, when viewed from the thickness direction X of the stretchable substrate, the first overlapping region 51 in which the adhesive layer 30 and the stretchable substrate 10 overlap each other, and a second overlapping region 52 in which the stretchable wiring 20 and the stretchable substrate 10 overlap each other but the stretchable wiring 20 and the adhesive layer 30 do not overlap each other. The second overlapping region 52, which is not provided with the adhesive layer 30, can be located between portions of the adhesive layers 30 that face each other at a distance. In other words, the stretchable device 100 comprises the adhesive layer 30 in the first overlapping region 51 but does not comprise the adhesive layer 30 in the second overlapping region 52. For this reason, for example, the first overlapping region 51 can be referred to as an "adhesive layer-present region," and the second overlapping region 52 can be referred to as an "adhesive layer-absent region" or a "wiring region without an adhesive layer." Therefore, in a cross-sectional view, in the second overlapping region 52 including the stretchable wiring 20, substantially no adhesive layer 30 is interposed between the stretchable wiring 20 and the adherend 200.

[0026] In the first overlapping region 51, the stretchable substrate 10 is adhered to the adherend 200 by the adhesive layer 30. Therefore, the stretchable substrate 10 in the first overlapping region 51 easily follows the shape and movement of the adherend 200 via the adhesive layer 30, and deformations such as wrinkles, bending, distortion, and / or flexure may occur in the stretchable substrate 10. On the other hand, in the second overlapping region 52, the adhesive layer 30 is not located between the stretchable substrate 10 and the adherend 200 in a cross-sectional view. Therefore, deformation of the stretchable substrate 10 that follows the shape and movement of the adherend 200 can be suppressed in the second overlapping region. In other words, the portion of the stretchable substrate 10 that does not overlap with the adhesive layer 30 is less likely to deform than the portion that overlaps with the adhesive layer 30. Note that "deformation" here refers to wrinkles, flexures, bending, curvatures, distortions, and / or folds, etc., that occur due to the shape and / or movement of the adherend. Suppressing deformation of the stretchable substrate 10 also suppresses deformation of the stretchable wiring 20 provided on the stretchable substrate 10, and therefore can suppress changes in the resistance value of the stretchable wiring 20. In other words, the stretchable device 100 of the present disclosure can indirectly achieve suppression of deformation of the stretchable wiring 20 by configuring the stretchable device 100 not to provide an adhesive layer 30 in a position that overlaps with the stretchable wiring 20 in the thickness direction X. Suppressing changes in the resistance value of the stretchable wiring by suppressing deformation reduces errors in signals transmitted by the stretchable wiring, and a high-precision stretchable device can be provided.

[0027] Furthermore, suppressing deformation of the stretchable wiring can also contribute to suppressing local concentration of stress due to bending of the stretchable wiring. That is, the above-mentioned structure reduces stress caused by deformation of the stretchable wiring, thereby suppressing the occurrence of physical damage such as breakage of the stretchable wiring and can also contribute to improving the durability of the stretchable device.

[0028] Furthermore, with this configuration, deformation of the stretchable substrate 10 and the stretchable wiring 20 can be suppressed in the second overlap region 52, while in the first overlap region 51 where the stretchable substrate 10 and the adhesive layer 30 overlap each other in the thickness direction X, the stretchable substrate 10 and the adhesive layer 30 can suitably stretch and contract in accordance with the shape and movement of the adherend 200. That is, in the stretchable device of the present disclosure, deformation of the stretchable wiring 20 can be suppressed without impairing the stretchability of the stretchable substrate 10 and the adhesive layer 30. This means that deformation of the stretchable wiring 20 can be suppressed without reinforcing the stretchable wiring 20 by, for example, using a stretchable substrate and / or adhesive layer 30 with a larger elastic modulus. Therefore, the present disclosure can provide a stretchable device that has stretchability that can suitably follow the shape and movement of the adherend 200, while suppressing changes in resistance value and breakage caused by deformation of the stretchable wiring.

[0029] 1 , the adhesive layer 30 may be disposed at a distance from the elastic wiring 20 when viewed from the thickness direction X of the elastic substrate. That is, a predetermined gap may be formed between the adhesive layer 30 and the elastic wiring 20 when viewed from the thickness direction X. Due to this gap, the elastic wiring 20 and the adhesive layer 30 are disposed at a distance so as not to overlap each other when viewed from the thickness direction X. That is, the adhesive layer 30 does not need to be disposed in the second overlapping region 52 that overlaps with the elastic wiring 20 when viewed from the thickness direction X, or in the periphery of this region.

[0030] According to this structure, the stretchable device 100 is configured so as not to overlap with the adhesive layer 30 not only in the region overlapping with the stretchable wiring 20 when viewed from the thickness direction X of the stretchable substrate, but also in the surrounding region. Therefore, deformation following the adhesive layer 30 can be suppressed even in the stretchable substrate 10 located in the vicinity of the stretchable wiring 20. Therefore, by more suitably suppressing the application of stress caused by the movement of the adherend 200 to the stretchable wiring, changes in resistance value due to deformation of the stretchable wiring can be suppressed.

[0031] In this embodiment, as shown in Figures 1 and 2, a mode in which one stretchable wire 20 is arranged is assumed, but the present invention is not limited to this, and two or more stretchable wires 20 may extend in any direction on the stretchable substrate 10. In such a structure, the adhesive layer 30 may be positioned between the multiple stretchable wires 20 when viewed from the thickness direction X of the stretchable substrate. That is, there may also be multiple second overlapping regions 52. Similarly, the number of adhesive layers 30 and first overlapping regions 51 is not limited.

[0032] 3 is a top view schematically illustrating the overall structure of the stretchable device 100 according to the first embodiment. As illustrated, the adhesive layer 30 may be positioned at least on the periphery of the stretchable substrate 10 when viewed from the thickness direction X. That is, when viewed from the thickness direction X of the stretchable substrate, the adhesive layer 30 may be arranged so as to overlap the contour portion (or outer edge) of the stretchable substrate 10. In a preferred embodiment, one continuous adhesive layer 30 may be provided along the periphery of the stretchable substrate 10. Alternatively, two or more adhesive layers 30 may be provided intermittently along the periphery of the stretchable substrate 10.

[0033] When viewed from the thickness direction X of the stretchable substrate, the stretchable wiring 20 may be positioned in a region 15 of the stretchable substrate 10 that is surrounded by the adhesive layer 30. As shown in FIG. 3 , the region 15 is a main surface region of the stretchable substrate 10 that is defined by the adhesive layer 30 arranged along the periphery of the stretchable substrate 10. Note that in FIG. 3 , the stretchable wiring 20 that may be arranged in this region 15 is omitted. For example, one or more stretchable wirings 20 may be arranged in the region 15 surrounded by the adhesive layer 30. When viewed from the thickness direction X, the stretchable wiring 20 may be surrounded by a single continuous adhesive layer 30. In other words, the adhesive layer 30 may have a frame-like shape in a plan view that surrounds the stretchable wiring 20. Furthermore, in this region 15, an additional adhesive layer 30 may be provided at a position that does not overlap with the stretchable wiring 20 when viewed from the thickness direction X.

[0034] According to this structure, the stretchable device 100 is mounted on the adherend 200 by the adhesive layer 30 provided around the periphery. That is, the stretchable device 100 can be bonded to the adherend 200 at the periphery of the stretchable device. Therefore, it is possible to suitably suppress deformation caused by movement of the adherend 200 in the stretchable substrate 10 located in the region 15 surrounded by the adhesive layer 30. Therefore, the stress that can be applied to the stretchable wiring 20 due to such deformation is reduced, and changes in the resistance value of the stretchable wiring 20 can be suitably suppressed.

[0035] Furthermore, when the stretchable device is in use, loosening and peeling of the stretchable device as a whole can be suitably suppressed by fixing the periphery of the stretchable device 100 to the adherend 200 by the adhesive layer 30. Therefore, the above-described structure can provide a stretchable device that has excellent holding power to the adherend 200 while suppressing deformation of the stretchable wiring 20.

[0036] The adhesive layer 30 may have a strip-like shape in a planar view. For example, the strip-like adhesive layer 30 may be disposed along the periphery of the stretchable device 100. When viewed from the thickness direction X of the stretchable substrate 10, the width of the adhesive layer 30 is preferably 0.3 mm or more, and more preferably 0.5 mm or more. When prioritizing the holding force of the stretchable device to the adherend 200, the width of the adhesive layer 30 is preferably 1 mm or more, 1.5 mm or more, or 2 mm or more. Furthermore, the width of the adhesive layer 30 is preferably 30 mm or less, 20 mm or less, or 15 mm or less. Note that the above-mentioned numerical ranges can be changed as appropriate depending on the dimensions of the stretchable device.

[0037] [First Modification of First Embodiment] Fig. 4 is a cross-sectional view schematically showing a stretchable device 101 according to a first modification of the first embodiment. The first modification of the first embodiment will be described with reference to Fig. 4. The stretchable device 101 differs from the stretchable device 100 according to the first embodiment in the arrangement of the stretchable wiring 20.

[0038] As shown in the figure, the stretchable wiring 20 may be positioned on the second main surface 12 side of the stretchable substrate. In other words, the stretchable wiring 20 may be arranged on the second main surface 12 side of the main surfaces of the stretchable substrate 10, which is located closer to the adherend 200. In such a configuration, the stretchable wiring 20 is located on the same main surface side as the adhesive layer 30. Therefore, both the stretchable wiring 20 and the adhesive layer 30 may be arranged on the second main surface 12 side of the stretchable substrate.

[0039] In the cross-sectional view shown in Fig. 4, the adhesive layer 30 is configured so as not to be interposed between the stretchable wiring 20 and the adherend 200. The adhesive layer 30 may be positioned in an area on the second main surface 12 side of the stretchable substrate where the stretchable wiring 20 is not disposed. This reduces the stress applied to the stretchable wiring 20 due to movement of the adherend 200, and can suitably suppress changes in the resistance value and breakage of the stretchable wiring 20.

[0040] Furthermore, according to the above-described configuration, it is possible to reduce the overall thickness of the stretchable device 101 compared to a configuration in which the stretchable wiring 20 is provided on the first main surface 11 side of the stretchable substrate. That is, by providing the stretchable wiring 20 and the adhesive layer 30 on the same main surface side of the stretchable substrate 10, the overall height of the stretchable device 101 can be reduced in the thickness direction X. This can reduce the discomfort felt when wearing the stretchable device, for example, when the adherend 200 is a living organism.

[0041] The stretchable device is also required to be re-attachable, taking into consideration the need to re-attach it to the adherend 200. If an adhesive layer 30 is provided between the stretchable wiring 20 and the adherend 200, when the stretchable device is peeled off from the adherend 200, the stretchable wiring 20 is pulled by the adhesive layer 30, which can cause problems such as peeling or breakage of the stretchable wiring 20. On the other hand, according to the structure of the present disclosure, the stretchable wiring 20 is not attached to the adherend 200 by the adhesive layer 30. Therefore, when the stretchable device 101 is peeled off from the adherend 200, stress such as tension from the adhesive layer 30 is less likely to be applied to the stretchable wiring 20, and therefore peeling, breakage, etc. of the stretchable wiring 20 can be suitably suppressed.

[0042] Furthermore, in general, the stretchable device 101 can be mounted on the adherend 200 to acquire and / or analyze information about the adherend 200 by electrical signals transmitted through the stretchable wiring 20. By positioning the stretchable wiring 20 on the second main surface 12 side of the stretchable substrate, the stretchable wiring 20 can be positioned closer to the adherend 200. Therefore, when the stretchable device is mounted on the adherend 200, the stretchable wiring 20 and electronic components such as sensors connected to the stretchable wiring 20 can be positioned closer to the adherend 200. This makes it possible for the stretchable device of the present disclosure to acquire information about the adherend 200 more precisely. That is, according to the above-described structure, a stretchable device with higher accuracy can be provided.

[0043] Furthermore, the thickness of the adhesive layer 30 may be greater than that of the stretchable wiring 20 located on the same main surface side. For example, as shown in Fig. 4, the adhesive layer 30 arranged so as to include mutually separated portions may have a thickness greater than that of the stretchable wiring 20 arranged between such separated portions. According to this configuration, when the stretchable device is attached to the adherend 200, a gap 40 is formed between the stretchable wiring 20 and the adherend 200. The adhesive layers 30 may be arranged so as to be separated from each other with such gap 40 therebetween.

[0044] For example, when a stretchable device is mounted on the skin of a living body, there is a possibility that the surface of the skin will become wet due to sweating or the like. If moisture penetrates the stretchable wiring 20, ion migration will occur, and there is a risk of the wiring short-circuiting. By providing the void 40, the above-described stretchable device 101 can be mounted on the adherend 200 without direct contact between the stretchable wiring 20 and the adherend 200. Therefore, adhesion of moisture to the stretchable wiring 20 is suppressed, and the reliability of the stretchable wiring 20 can be improved.

[0045] Furthermore, with the above-described structure, the stretchable device 101 is not bonded to the adherend 200 over the entire surface, and can be in a non-contact state with the adherend 200 in the portion where the void 40 is formed. Therefore, the contact area between the stretchable device and the adherend is reduced, and therefore, when the stretchable device is attached to a living body, irritation to the skin caused by contact with the stretchable device can be reduced. Furthermore, the above-described structure including the void 40 can also contribute to improving breathability between the stretchable device and the skin.

[0046] For example, the thickness of the adhesive layer 30 is preferably 110% or more of the thickness of the stretchable wiring 20, more preferably 150% or more, and even more preferably 200% or more. When the thickness of the stretchable wiring 20 is within the above-mentioned range, it is possible to obtain a suitable stretchable device with improved reliability of the stretchable wiring 20. Furthermore, from the viewpoint of not inhibiting the movement of the adherend 200 when attached to the adherend 200 such as a living organism, the thickness of the adhesive layer 30 is preferably 500% or less of the thickness of the stretchable wiring 20, more preferably 400% or less, and even more preferably 300% or less.

[0047] [Second Modification of First Embodiment] Fig. 5 is a cross-sectional view schematically showing a stretchable device 102 according to a second modification of the first embodiment. The second modification of the first embodiment will be described with reference to Fig. 5. The stretchable device 102 differs from the stretchable device 100 according to the first embodiment in the relative positional relationship between the stretchable wiring 20 and the adhesive layer 30.

[0048] As shown in the figure, when viewed from the thickness direction X of the stretchable substrate, the adhesive layer 30 and at least a part of the edge portion 25 of the stretchable wiring 20 may overlap each other. In the present specification, the "edge portion of the stretchable wiring" means, in a cross-sectional view, an edge including a surface located on the proximal side with respect to the stretchable substrate 10 among the outer surfaces of the stretchable wiring 20, and includes an edge including a side surface 23 extending in the stretching direction of the stretchable wiring 20 and an edge including an end surface extending in the width direction of the stretchable wiring 20. When viewed from the thickness direction X of the stretchable substrate, the adhesive layer 30 may be arranged so as to at least partially overlap at the edge portion 25 of the stretchable wiring. Specifically, the adhesive layer 30 may be configured so as not to overlap with the outer main surface 21 of the stretchable wiring 20 but only to overlap with at least a part of the edge portion 25 when viewed from the thickness direction X of the stretchable substrate.

[0049] For example, the adhesive layer 30 may be in contact with the edge portion 25 of the stretchable wiring. In other words, the first overlapping region 51 including the adhesive layer 30 and the second overlapping region 52 including the stretchable wiring 20 may be in contact with each other. As shown in FIG. 5, when the cross-sectional view shape of the outer surface of the stretchable wiring 20 includes a curved surface, a portion located on the proximal side with respect to the stretchable substrate 10 on the outer surface of the stretchable wiring 20 may be in contact with the adhesive layer 30. Alternatively, when the cross-sectional view shape of the stretchable wiring 20 is rectangular, at least a part of the side surface 23 of the stretchable wiring extending along the thickness direction X of the stretchable substrate may be in contact with the adhesive layer 30. For example, although the stretchable wiring 20 having a rectangular cross-sectional view shape shown in FIG. 4 is shown separated from the adhesive layer 30, at least a part of the side surface 23 of the stretchable wiring may be in contact with the adhesive layer 30.

[0050] According to such a configuration, the area of the adhesive layer 30 contributing to the bonding between the stretchable device 102 and the adherend 200 is further enlarged. Therefore, the adhesive force of the stretchable device 102 as a whole can be improved. Thereby, the stretchable device can be preferably held in a state where it is attached to the adherend 200 and properly bonded to the adherend 200.

[0051] [Third Modification of First Embodiment] Fig. 6 is a cross-sectional view schematically showing a stretchable device 103 according to a third modification of the first embodiment. The third modification of the first embodiment will be described with reference to Fig. 6. The stretchable device 103 differs from the stretchable device 102 according to the first embodiment in that it includes a covering layer 60 for the stretchable wiring 20.

[0052] The stretchable wiring 20 may be covered by a covering layer 60. For example, the covering layer 60 may cover the outer surface of the stretchable wiring 20. In this specification, the term "outside" refers to the side relatively far from the stretchable substrate 10, and does not have to coincide with the outside during actual use. The covering layer 60 may cover the outermost surface of the stretchable wiring 20. In a stretchable device, the stretchable wiring 20 only needs to be covered so that the stretchable wiring 20 is not exposed, and a part of the stretchable wiring 20 may be covered by a member other than the covering layer 60.

[0053] By disposing the covering layer 60, it is possible to suppress the penetration of moisture into the stretchable wire 20 from the outside. The covering layer 60 preferably covers the outer main surface 21 of the stretchable wire 20, and more preferably covers the side surface 23. That is, the covering layer 60 may be in contact with the outer main surface 21 and the side surface 23 of the stretchable wire 20. By covering each outer surface of the stretchable wire 20 with the covering layer 60, it is possible to prevent contact between the stretchable wire 20 and the adherend 200. Furthermore, the covering layer 60 that covers the stretchable wire 20 may be in contact with the stretchable substrate 10. This can more suitably suppress the penetration of moisture into the stretchable wire 20 from the outside. That is, with such a structure, the occurrence of ion migration caused by the penetration of moisture into the stretchable wire 20 is suppressed, and a stretchable device with higher connection reliability can be provided.

[0054] It is more preferable that the covering layer 60 covers at least the entire main surface of the stretchable wiring 20 and the stretchable substrate 10 on which the stretchable wiring 20 is provided. That is, the covering layer 60 may integrally cover the stretchable wiring 20 and the main surface of the stretchable substrate 10 on which the stretchable wiring 20 is provided. Note that "the entire" main surface of the stretchable substrate 10 refers to a region in a region that may come into contact with an adherend when the main surface is exposed. For example, in a portion where the stretchable wiring 20 is connected to electronic components and / or other wiring, there may be a region where the covering layer 60 is not disposed. Alternatively, the covering layer may be disposed so as to cover the main surface of the stretchable substrate 10 and all elements that may be disposed on the main surface, including the portion connected to the stretchable wiring 20, electronic components and / or other wiring.

[0055] In another embodiment, the covering layer 60 may be disposed between the stretchable substrate 10 and the stretchable wire 20. In other words, the surface of the stretchable wire 20 closest to the stretchable substrate 10 may be in contact with the covering layer 60. The entire surface of the stretchable wire 20 may be covered by the covering layer 60. In this way, by disposing the covering layer 60 between the stretchable substrate 10 and the stretchable wire 20, it is possible to prevent moisture that has permeated the stretchable substrate 10 or moisture absorbed by the stretchable substrate 10 from penetrating the stretchable wire 20. Therefore, according to the above-described configuration, a stretchable device in which ion migration of the stretchable wire 20 is more suitably prevented can be provided.

[0056] Furthermore, in such a configuration, the covering layer 60 does not necessarily have to be formed of a single layer, and may be formed of two or more covering layers. For example, the stretchable wire 20 may be surrounded by a first covering layer interposed between the stretchable substrate 10 and the stretchable wire 20, and a second covering layer covering the outer surfaces (21, 23) of the stretchable wire 20.

[0057] 6 , the adhesive layer 30 may be provided on a covering layer 60. In a preferred embodiment, the covering layer 60 is provided across the second main surface 12 of the stretchable substrate on which the stretchable wiring 20 is located, and the adhesive layer 30 is disposed on the second main surface 12 of the stretchable substrate via the covering layer 60. That is, the covering layer 60 may be located between the stretchable substrate 10 and the adhesive layer 30 in a cross-sectional view.

[0058] According to this configuration, the stretchable substrate 10 can be protected by the covering layer 60. This makes it possible to prevent damage to the stretchable substrate 10 due to stress that occurs when the stretchable device is peeled off from an adherend in order to reattach the stretchable device. Furthermore, even in the case where the edge portion 25 of the stretchable wiring and the adhesive layer 30 overlap each other as viewed from the thickness direction X, the stretchable wiring 20 and the adhesive layer 30 are not in direct contact with each other, and therefore it is possible to suitably avoid the occurrence of problems such as damage to the stretchable wiring 20 during the operation of peeling off the stretchable device.

[0059] The coating layer 60 is made of, for example, a resin material or a mixture containing a resin material and an inorganic material. Examples of resin materials include urethane-based, styrene-based, olefin-based, silicone-based, fluorine-based, nitrile rubber, latex rubber, vinyl chloride, ester-based, amide-based, and other elastomer-based resins, as well as epoxy, phenolic, acrylic, polyester, imide-based, rosin, cellulose, polyethylene terephthalate-based, polyethylene naphthalate-based, and polycarbonate-based resins. The coating layer 60 does not have to be made of a single material. The resin material may be a UV-curable resin that hardens by absorbing ultraviolet light. The UV-curable resin may be, for example, an acrylic resin material containing a UV curing agent.

[0060] The thickness of the coating layer 60 is not particularly limited, but is preferably 100 μm or less, more preferably 80 μm or less, and even more preferably 50 μm or less. The thickness of the coating layer 60 is preferably 1 μm or more.

[0061] A method for producing the stretchable device 100 according to the first embodiment (corresponding to the basic embodiment) will be described below.

[0062] First, a stretchable substrate 10 is prepared. After the stretchable substrate 10 is prepared, a stretchable wiring 20 is formed on the first main surface 11 or the second main surface 12 of the stretchable substrate 10. After the stretchable wiring 20 is formed, an adhesive layer 30 is disposed in a position that does not overlap with the outer main surface 21 of the stretchable wiring when viewed from the thickness direction X of the stretchable substrate. For example, one continuous adhesive layer 30 is disposed along the periphery of the stretchable substrate 10.

[0063] In this manner, the stretchable device 100 according to the first embodiment (corresponding to the basic embodiment) can be fabricated.

[0064] When producing a stretchable device according to the third modified example of the first embodiment, after forming the stretchable wiring 20 on the second main surface 12 of the stretchable substrate, a covering layer 60 is formed so as to integrally cover the stretchable wiring 20 and the second main surface 12 of the stretchable substrate. After forming the covering layer 60, an adhesive layer 30 is disposed on the covering layer 60 at a position that does not overlap with the outer main surface 21 of the stretchable wiring when viewed from the thickness direction X of the stretchable substrate. In this way, a stretchable device 100 according to the third modified example of the first embodiment can be produced.

[0065] Furthermore, when producing a stretchable device according to a second embodiment described below, a step of arranging an electronic component 70 described below is included before the step of arranging the adhesive layer 30 (see FIGS. 7 and 8 ). Specifically, after forming the stretchable wiring 20 on the second main surface 12 of the stretchable substrate, the electronic component 70 is arranged on the second main surface 12 and electrically connected to the stretchable wiring 20. Thereafter, the adhesive layer 30 is arranged on the electronic component 70 in addition to on the stretchable substrate 10 and / or the covering layer 60. In this manner, the stretchable device according to the second embodiment can be produced.

[0066] Furthermore, when producing a stretchable device according to a modified example of the second embodiment, which will be described later, after arranging the electronic component 70, the electronic component 70 is covered with a protective member 80 (see FIG. 9 ). Then, an adhesive layer 30 is arranged on the protective member 80 and on the stretchable substrate 10 and / or the covering layer 60. In this manner, a stretchable device according to a modified example of the second embodiment can be produced.

[0067] [Second embodiment] Fig. 7 is an enlarged top view of a region of a stretchable device where an electronic component 70 is mounted. Fig. 8 is a cross-sectional view schematically showing a stretchable device according to a second embodiment. The second embodiment will be described with reference to Figs. 7 and 8. The stretchable device differs from the stretchable device according to the first embodiment in that it includes an electronic component 70.

[0068] As shown in Fig. 7, the stretchable wire 20 may be connected to an electronic component 70. Although not shown, the electronic component 70 may be connected to the stretchable wire 20 by solder and / or a conductive adhesive, or the like. Alternatively, the electronic component 70 may be directly connected to the stretchable wire 20. The electronic component 70 may be disposed on the stretchable substrate 10, and may be electrically connected to the stretchable wire 20.

[0069] The electronic component 70 can be various electronic components used depending on the application of the stretchable device. By way of example only, the electronic component 70 may be an LED, a field-effect transistor (FET), an operational amplifier, a capacitor, a resistor, a thermistor, a strain gauge, a color sensor, or the like. In one embodiment, the electronic component 70 is configured to detect signals related to the adherend 200 and may be disposed on the second main surface 12 side of the stretchable substrate. Examples of signals to be acquired include signals related to the temperature, color, vibration, and the like of the adherend 200. For example, if the adherend 200 is a living organism, the electronic component 70 may be capable of acquiring signals related to the target organism's body temperature, pulse rate, blood oxygen saturation, blood pressure, electrocardiogram signals, electrical conductivity of the body surface, skin movement (e.g., skin expansion / contraction, changes in strain, etc.), and the like. The electronic component 70 may be configured to include sensors corresponding to the types of signals to be acquired. Furthermore, the electronic component 70 may include multiple types of sensors so as to acquire multiple types of signals. Alternatively, the stretchable device may include multiple electronic components with one or more sensors of the same or different types.

[0070] 8 , when viewed from the thickness direction X of the stretchable substrate, the electronic component 70 and the adhesive layer 30 may overlap each other. That is, in a cross-sectional view, the adhesive layer 30 may be positioned between the electronic component 70 and the adherend 200. The adhesive layer 30 that overlaps the electronic component 70 in a plan view may be attachable to the adherend 200. In other words, the electronic component 70 may be attached to the adherend 200 by the adhesive layer 30. That is, when the stretchable device is attached, the electronic component 70 is attached to the adherend 200 by the adhesive layer 30, and the electronic component 70 and the adherend 200 are held in an attached state to each other via the adhesive layer 30.

[0071] With this configuration, the electronic component 70 can be held in closer contact with the adherend surface that is the measurement target. Therefore, information about the adherend 200 can be acquired with higher sensitivity. Furthermore, because the position of the electronic component 70 is suitably fixed on the adherend 200 by the adhesive layer 30, positional deviation of the electronic component 70 during detection can be suppressed, and detection errors can be reduced. Therefore, with the above-described configuration, a suitable stretchable device can be provided that both suppresses changes in the resistance value of the stretchable wiring 20 caused by deformation of the stretchable device and improves detection accuracy.

[0072] 9 and 10 are cross-sectional views schematically showing a stretchable device according to a modification of the second embodiment. The modification of the second embodiment will be described with reference to FIGS. 9 and 10. The stretchable device differs from the stretchable device according to the second embodiment in that it includes a protective member 80 for the electronic component 70.

[0073] As shown in the figure, the electronic component 70 may be covered by a protective member 80. For example, the protective member 80 may cover the outer surface of the electronic component 70 other than the surface facing the stretchable substrate 10. In such a structure, the protective member 80 functions as a sealing member that protects the electronic component 70. Although not shown, the protective member 80 may be in contact with the stretchable wiring 20 connected to the electronic component 70. Furthermore, the protective member 80 may be in contact with the stretchable substrate 10. As shown in FIG. 10 , the protective member 80 may also be disposed between the stretchable substrate 10 and the electronic component 70. This can more effectively prevent moisture from penetrating the electronic component 70 from the outside.

[0074] In a cross-sectional view, the adhesive layer 30 may be provided between the protective member 80 and the adherend 200. When viewed from the thickness direction X of the stretchable substrate, the electronic component 70, the protective member 80, and the adhesive layer 30 may overlap one another. That is, the electronic component 70 can be attached to the adherend 200 by the adhesive layer 30, with the protective member 80 interposed therebetween.

[0075] According to this configuration, the electronic component 70 is protected by the protective member 80, and therefore it is possible to prevent the electronic component 70 from being damaged by stress that occurs when the stretchable device is peeled off for re-attachment. Furthermore, by configuring the protective member 80 to be in contact with the stretchable wiring 20, the connection point between the electronic component 70 and the stretchable wiring 20 is covered by the protective member 80. Therefore, the above-described structure including the protective member 80 can also contribute to improving the connection reliability between the electronic component 70 and the stretchable wiring 20.

[0076] The protective member 80 may be made of a resin material. For example, the protective member 80 may be made of an elastomer resin such as polyvinyl chloride, polyethylene, polystyrene, polycarbonate, polyvinylidene fluoride, polyimide, liquid crystal polymer, polytetrafluoroethylene, phenolic resin, epoxy resin, urethane resin, acrylic resin, silicone resin, or styrene-butadiene resin. The protective member 80 may be made of a plurality of components.

[0077] Although the embodiments of the present disclosure have been described above, they are merely typical examples. Those skilled in the art will readily understand that the present disclosure is not limited thereto, and that various modifications are possible within the scope of the present disclosure.

[0078] It should be noted that one embodiment of the present disclosure as described above includes the following preferred aspects. First aspect: A stretchable device comprising a stretchable substrate, stretchable wiring provided on the stretchable substrate, and an adhesive layer having portions that face each other at a distance, wherein, as viewed in the thickness direction of the stretchable substrate, the stretchable wiring is located between the portions of the adhesive layer that face each other at a distance. Second aspect: A stretchable device in the first aspect above, wherein, as viewed in the thickness direction of the stretchable substrate, at least a main surface of the stretchable wiring that faces the stretchable substrate and the adhesive layer do not overlap each other. Third aspect: A stretchable device in the first aspect or the second aspect above, wherein, as viewed in the thickness direction of the stretchable substrate, the stretchable wiring is surrounded by one continuous adhesive layer. Fourth aspect: A stretchable device in any of the first to third aspects, comprising a first overlapping region where the stretchable substrate and the adhesive layer overlap each other, and a second overlapping region where the stretchable substrate and the stretchable wiring overlap each other but do not overlap with the adhesive layer, as viewed in the thickness direction of the stretchable substrate. Fifth aspect: A stretchable device in any of the first to fourth aspects, wherein the adhesive layer and the stretchable wiring are arranged spaced apart from each other, as viewed in the thickness direction of the stretchable substrate. Sixth aspect: A stretchable device in any of the first to fifth aspects, wherein the stretchable wiring and the adhesive layer are located on the same main surface side of the stretchable substrate. Seventh aspect: A stretchable device in any of the first to sixth aspects, wherein the thickness of the adhesive layer is greater than the thickness of the stretchable wiring. Eighth aspect: A stretchable device in the seventh aspect, wherein a gap is present between the stretchable wiring and the adherend in a cross-sectional view. Ninth aspect: The stretchable device according to any one of the first to fourth aspects and the sixth to eighth aspects, wherein the adhesive layer and at least a part of an edge portion of the stretchable wiring overlap each other when viewed in the thickness direction of the stretchable substrate. Tenth aspect: The stretchable device according to claim 9, wherein the adhesive layer and the edge portion are in contact with each other in the ninth aspect. Eleventh aspect: The stretchable device according to any one of the first to tenth aspects, wherein the stretchable wiring is covered with a covering layer.12th aspect: The stretchable device of the 11th aspect, wherein the covering layer is provided across a main surface of the stretchable substrate on which the stretchable wiring is located, and the covering layer has a portion that overlaps with the adhesive layer when viewed in the thickness direction of the stretchable substrate. 13th aspect: The stretchable device of any of the 1st to 12th aspects, further comprising an electronic component provided on the stretchable substrate, and the electronic component and the adhesive layer overlap when viewed in the thickness direction of the stretchable substrate. 14th aspect: The stretchable device of the 13th aspect, wherein the adhesive layer that overlaps with the electronic component is attachable to the adherend. 15th aspect: The stretchable device of the 13th or 14th aspect, wherein the electronic component is covered with a protective member. 16th aspect: The stretchable device of the 15th aspect, wherein the protective member is located between the electronic component and the adhesive layer when viewed in cross section. 17th aspect: The stretchable device according to any one of the first to sixteenth aspects, wherein the width of the adhesive layer is 1 mm or more and 20 mm or less.

[0079] 100, 101 to 105: Stretchable device 10: Stretchable substrate 11: First main surface 12: Second main surface 15: Region surrounded by adhesive layer 20: Stretchable wire 21: Outer main surface of stretchable wire 23: Side surface of stretchable wire 25: Edge portion of stretchable wire 30: Adhesive layer 31: Substrate side main surface of adhesive layer 32: Mounting side main surface of adhesive layer 40: Gap 51: First overlapping region 52: Second overlapping region 60: Covering layer 70: Electronic component 80: Protective member 200: Adherend X: Thickness direction of stretchable substrate

Claims

1. The present invention comprises a stretchable substrate, a stretchable wiring provided on the stretchable substrate, and an adhesive layer having portions spaced apart and facing each other, When viewed in the thickness direction of the elastic substrate, the elastic wiring is located between the mutually spaced and opposing portions of the adhesive layer, A stretchable device, in which the adhesive layer and at least a portion of an edge portion of the stretchable wiring overlap each other when viewed in the thickness direction of the stretchable substrate.

2. A device comprising: a stretchable substrate; stretchable wiring provided on the stretchable substrate; and an adhesive layer having portions spaced apart and facing each other; When viewed in the thickness direction of the elastic substrate, the elastic wiring is located between the mutually spaced and opposing portions of the adhesive layer, The adhesive layer includes a first portion that overlaps at least a part of an edge portion of the elastic wire on both sides in the width direction of the elastic wire, The first portion extends in the extension direction of the stretchable wiring.

3. A device comprising: a stretchable substrate; stretchable wiring provided on the stretchable substrate; and an adhesive layer having portions spaced apart and facing each other; When viewed in the thickness direction of the elastic substrate, the elastic wiring is located between the mutually spaced and opposing portions of the adhesive layer, The thickness of the adhesive layer is greater than the thickness of the elastic wiring, and in cross-sectional view, there is a gap between the elastic wiring and the adherend.

4. The stretchable device according to any one of claims 1 to 3, wherein at least the outer main surface of the stretchable wiring facing the stretchable substrate and the adhesive layer do not overlap with each other when viewed in the thickness direction of the stretchable substrate.

5. The stretchable device according to any one of claims 1 to 3, wherein the stretchable wiring is surrounded by one continuous adhesive layer when viewed in the thickness direction of the stretchable substrate.

6. The stretchable device according to any one of claims 1 to 3, comprising a first overlapping region in which the stretchable substrate and the adhesive layer overlap each other when viewed in the thickness direction of the stretchable substrate, and a second overlapping region in which the stretchable substrate and the stretchable wiring overlap each other and do not overlap the adhesive layer.

7. The stretchable device according to claim 3 , wherein the adhesive layer is disposed apart from the stretchable wiring when viewed in a thickness direction of the stretchable substrate.

8. The stretchable device according to claim 3 , wherein the adhesive layer and at least a portion of an edge of the stretchable wiring overlap each other when viewed in the thickness direction of the stretchable substrate.

9. 9. The stretchable device of claim 8, wherein the adhesive layer and the edge are in contact.

10. The stretchable device according to any one of claims 1 to 3, wherein the stretchable wiring and the adhesive layer are located on the same main surface side of the stretchable substrate.

11. The stretchable device according to claim 1 or 2, wherein the thickness of the adhesive layer is greater than the thickness of the stretchable wiring.

12. The stretchable device according to claim 11, having a gap between the stretchable wiring and the adherend in a cross-sectional view.

13. The stretchable device according to any one of claims 1 to 3, wherein the stretchable wiring is covered with a covering layer.

14. The covering layer is provided over the main surface of the elastic substrate on which the elastic wiring is located, The stretchable device according to claim 13 , wherein the covering layer and the adhesive layer have a portion that overlaps each other when viewed in a thickness direction of the stretchable substrate.

15. The stretchable device according to any one of claims 1 to 3, further comprising an electronic component provided on the stretchable substrate, and the electronic component and the adhesive layer overlap each other when viewed in the thickness direction of the stretchable substrate.

16. The stretchable device according to claim 15, wherein the adhesive layer overlapping the electronic component is attachable to an adherend.

17. The stretchable device according to claim 15, wherein the electronic component is covered with a protective member.

18. The stretchable device according to claim 17 , wherein the protective member is located between the electronic component and the adhesive layer in a cross-sectional view.

19. The stretchable device according to any one of claims 1 to 3, wherein the width of the adhesive layer is 1 mm or more and 20 mm or less.