Stretchable Devices

Abstract

To provide a stretchable device in which deterioration in IR (insulation resistance) between wirings can be suppressed.SOLUTION: In an embodiment of the present invention, a stretchable device is provided, including: stretchable base material 10; first stretchable wiring 20 and second stretchable wiring 40 provided on the stretchable base material and partially overlapped on each other in a thickness direction of the stretchable base material; an insulation layer 30 arranged on a wiring overlapping portion between the first stretchable wiring and the second stretchable wiring; and a first pressure-sensitive-adhesive layer 50 overlapped on at least a part of the insulation layer in the thickness direction. The first pressure-sensitive-adhesive layer has expansion / contraction performance relatively smaller than that in the insulation layer.SELECTED DRAWING: Figure 4

Description

[Technical field]

[0001] The present invention relates to a stretchable device. [Background technology]

[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 when in use.

[0003] The stretchable device includes a stretchable substrate, a first stretchable wiring provided on the stretchable substrate, a second stretchable wiring arranged on the first stretchable wiring, an insulating layer arranged in a wiring overlap portion between the first stretchable wiring and the second stretchable wiring, and an adhesive layer for mounting (see Patent Document 1). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent Publication No. 2021-64676 Summary of the Invention [Problem to be solved by the invention]

[0005] However, depending on the properties of the adhesive layer or the bonding layer, the thickness of the insulating layer located at the overlapping portion between the two elastic wirings may become thinner during stretching. Such a reduction in the thickness of the insulating layer leads to a reduction in the IR (insulation resistance) between the two wirings. As a result, there is a risk of a reduction in the device's functions such as sensing and signal communication, as well as the occurrence of short circuits due to ion migration and wiring contact.

[0006] Therefore, an object of the present invention is to provide a stretchable device capable of suppressing a decrease in IR (insulation resistance) between wirings. [Means for solving the problem]

[0007] In order to achieve the above object, in one embodiment of the present invention, A stretchable device is provided, comprising: a stretchable substrate; a first stretchable wiring and a second stretchable wiring provided on the stretchable substrate and partially overlapping each other in a thickness direction of the stretchable substrate; an insulating layer disposed in a wiring overlap portion between the first stretchable wiring and the second stretchable wiring; and a first adhesive layer overlapping at least a portion of the insulating layer in the thickness direction, wherein the first adhesive layer has a stretchability relatively smaller than that of the insulating layer. Effect of the Invention

[0008] According to a stretchable device according to an embodiment of the present invention, it is possible to suppress a decrease in IR (insulation resistance) between wirings. [Brief description of the drawings]

[0009] [Figure 1] FIG. 1 is a plan view illustrating a stretchable device according to a first embodiment of the present invention. [Diagram 2] FIG. 2 is a partially enlarged schematic plan view of the stretchable device according to the first embodiment of the present invention. [Diagram 3] FIG. 3 is a partially enlarged schematic cross-sectional view of the stretchable device according to the first embodiment of the present invention taken along line XX in FIG. 2 before stretching. [Figure 4] FIG. 4 is a partially enlarged schematic cross-sectional view of the stretchable device according to the first embodiment of the present invention taken along line XX in FIG. 2 during stretching. [Diagram 5] FIG. 5 is a partially enlarged schematic cross-sectional view of Modification 1 of the stretchable device according to the first embodiment of the present invention (corresponding to the cross-sectional view taken along line XX in FIG. 2). [Figure 6] FIG. 6 is a partially enlarged schematic cross-sectional view of Modification 2 of the stretchable device according to the first embodiment of the present invention (corresponding to the cross-sectional view taken along line XX in FIG. 2). [Figure 7] FIG. 7 is a partially enlarged schematic cross-sectional view of a stretchable device according to a second embodiment of the present invention (corresponding to the cross-sectional view taken along line XX in FIG. 2). [Figure 8]FIG. 8 is a partially enlarged schematic cross-sectional view of Modification 1 of the stretchable device according to the second embodiment of the present invention (corresponding to the cross-sectional view taken along line XX in FIG. 2). [Figure 9] FIG. 9 is a partially enlarged schematic cross-sectional view of Modification 2 of the stretchable device according to the second embodiment of the present invention (corresponding to the cross-sectional view taken along line XX in FIG. 2). [Figure 10] FIG. 10 is a plan view illustrating a stretchable device according to a third embodiment of the present invention. [Figure 11] FIG. 11 is a partially enlarged schematic cross-sectional view of the stretchable device according to the third embodiment of the present invention taken along line segment YY in FIG. [Figure 12] FIG. 12 is a plan view illustrating a stretchable device according to a fourth embodiment of the present invention. [Figure 13] FIG. 13 is a partially enlarged schematic cross-sectional view of the stretchable device according to the fourth embodiment of the present invention taken along line segment ZZ in FIG. [Figure 14] FIG. 14 is a plan view illustrating a stretchable device according to a fifth embodiment of the present invention. [Figure 15] FIG. 15 is a partially enlarged schematic cross-sectional view of the stretchable device according to the fifth embodiment of the present invention taken along line segment WW in FIG. [Figure 16] FIG. 16 is a partially enlarged schematic cross-sectional view of a conventional stretchable device before stretching. [Figure 17] FIG. 17 is a partially enlarged schematic cross-sectional view of a conventional stretchable device during stretching. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] Hereinafter, the embodiments of the present invention will be described in detail with reference to the drawings. In each embodiment, differences from the previous embodiment will be mainly described. In particular, similar effects due to similar configurations will not be mentioned in each embodiment. Among the components in the following embodiments, components that are not described in the independent claims will be described as optional components. In addition, the size and size ratio of the components shown in the drawings are not necessarily strict. In addition, in each figure, the same reference numerals are given to substantially the same configurations, and duplicated descriptions may be omitted or simplified.

[0011] [First embodiment] Hereinafter, the configuration of the stretchable device 100 according to the first embodiment will be described with reference to FIGS.

[0012] FIG. 1 is a plan view showing a schematic diagram of a stretchable device according to a first embodiment of the present invention. FIG. 2 is a partially enlarged schematic plan view of a stretchable device according to a first embodiment of the present invention. FIG. 3 is a partially enlarged schematic cross-sectional view of the stretchable device according to the first embodiment of the present invention taken along line XX in FIG. 2 before stretching. FIG. 4 is a partially enlarged schematic cross-sectional view of the stretchable device according to the first embodiment of the present invention taken along line XX in FIG. 2 during stretching. In addition, in the cross-sectional views in this specification, the thickness direction of the stretchable substrate described later is indicated by a double-headed arrow X. In addition, FIG. 3 and FIG. 4 are cross-sectional views taken along line XX in FIG. 2, that is, in the extension direction of the first stretchable wiring.

[0013] The stretchable device 100 according to the first embodiment of the present invention comprises a stretchable substrate 10, a first stretchable wire 20, a second stretchable wire 40, an insulating layer 30 and a first adhesive layer 50 (see FIGS. 1 to 4).

[0014] The components of the stretchable device 100 will be specifically described below, followed by a description of the characteristic features of the first embodiment.

[0015] (Stretchable base material 10) The stretchable substrate 10 is a sheet-like or film-like stretchable substrate, and is made of, for example, a resin material having stretchability. Examples of the resin material for the stretchable substrate 10 include thermoplastic polyurethane (TPU), polyethylene (PE), polystyrene (PS), and polyethylene terephthalate (PET).

[0016] The thickness of the stretchable substrate 10 is not particularly limited, but is preferably 100 μm or less, more preferably 50 μm or less, from the viewpoint of not inhibiting the stretching of the surface of the living body when attached to the living body. Also, the thickness of the stretchable substrate 1 is preferably 20 μm or more, from the viewpoint of ensuring a predetermined strength.

[0017] (1st elastic wiring 20 / 2nd elastic wiring 40) The first elastic wire 20 and the second elastic wire 40 are provided on the elastic substrate 10, specifically on its main surface, and partially overlap each other in the thickness direction X of the elastic substrate 10.

[0018] In this specification, "above" includes a state of being located above an element and separated from it, i.e., being located above an element via another object, a state of being located above an element with a gap, and a state of being located directly above and in contact with an element.

[0019] Therefore, in this specification, "the first stretchable wiring 20 and the second stretchable wiring 40 arranged on the stretchable substrate 10" includes the first and second stretchable wirings 20, 40 in contact with the main surface of the stretchable substrate 10, and the first and second stretchable wirings 20, 40 in a state where they are separated from the main surface via another member (for example, a resin layer described below) without directly contacting the main surface of the stretchable substrate 10.

[0020] In one example, as shown in Fig. 1, the first elastic wiring 20 and the second elastic wiring 40 form a wiring intersection portion where they intersect with each other. For example, the first elastic wiring 20 and the second elastic wiring 40 form a wiring intersection portion where they intersect perpendicularly with each other. The first elastic wiring 20 and the second elastic wiring 40 are each electrically connected to the electronic component 200.

[0021] Each of the first elastic wire 20 and the second elastic wire 40 includes conductive particles and a resin. For example, the elastic wires may be a mixture of metal powder such as Ag, Cu, Ni, etc. 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. In addition, the shape of the conductive particles is preferably spherical.

[0022] The thickness of each elastic wire is not particularly limited, but is preferably 100 μm or less, more preferably 50 μm or less. The thickness of each elastic wire is preferably 0.01 μm or more. The line width of each elastic wire is not particularly limited, but is preferably 0.1 μm or more, more preferably 10 mm or less. The shape and number of each elastic wire are not particularly limited.

[0023] From the viewpoint of more reliably preventing a short circuit during use of the stretchable device 100, the extension direction of the first stretchable wire 20 is preferably the longitudinal direction of the stretchable device 100 (ie, the stretching direction).

[0024] (Insulating layer 30) The insulating layer 30 is a layer disposed to prevent short circuits due to contact between the elastic wires. Specifically, the insulating layer 30 is disposed in a wire overlapping portion 70 between the first elastic wire 20 and the second elastic wire 40. From the viewpoint of suitably avoiding contact between the wires, the width of the insulating layer 30 is equal to or greater than the width of the second elastic wire 40 in a cross-sectional view, and is preferably greater than the width of the second elastic wire 40.

[0025] The insulating layer 30 may be made of at least one resin material selected from the group consisting of polyimide, epoxy, urethane, and acrylic resins, or may be made of an inorganic material such as alumina or silicon dioxide.

[0026] (1st adhesive layer 50) The first adhesive layer 50 is disposed so as to overlap at least a portion of the insulating layer 30 in the thickness direction X of the elastic substrate 10. That is, the first adhesive layer 50 is disposed so as to overlap the wiring overlapping portions 70 (e.g., wiring intersection portions) of both the elastic wires 20, 40 in the thickness direction X of the elastic substrate.

[0027] The first adhesive layer 50 has adhesiveness that allows the stretchable device 100 to be attached to an adherend 300, such as a living body. In one example, the first adhesive layer 50 can be positioned between the stretchable substrate 10 and the adherend 300, such as a living body.

[0028] The first adhesive layer 50 has a first main surface 51 on the side of the adherend 300, such as a living body, and a second main surface 52 on the opposite side. The first adhesive layer 50 preferably has adhesiveness on both main surfaces. The first main surface 51 of the first adhesive layer 50 can be attached to a living body or the like. Note that a mode is also possible in which the first main surface 51 of the first adhesive layer 50 itself is attached to another layer, and then the other layer is attached to the living body or the like.

[0029] The second main surface 52 of the first adhesive layer 50 can be attached to the stretchable substrate 10. A protective layer, which will be described later, may be further disposed between the second main surface 52 of the first adhesive layer 50 and the stretchable substrate 10 from the viewpoint of improving waterproofing, etc.

[0030] There are no particular limitations on the adhesive that can be used for the first adhesive layer 50, so long as it is a pressure-sensitive adhesive that is mild to the skin and has sufficient pressure-sensitive adhesiveness, yet can be easily peeled off from the skin after use.

[0031] Although not particularly limited, the first adhesive layer 50 may be composed of a pressure-sensitive adhesive or the like. There is no particular limitation on the pressure-sensitive adhesive, so long as it is one that can be laminated on the elastic substrate 10 and generally used. For example, rubber-based, acrylic-based, and silicone-based pressure-sensitive adhesives can be used. When a pressure-sensitive adhesive is used, it is possible to bond to the opposing member (elastic substrate, protective layer described later) at a relatively low temperature, so that it is possible to prevent deterioration and distortion of the elastic substrate 10 by using excessive heat or UV energy.

[0032] 1 to 4 show an embodiment in which the insulating layer 30 and the first adhesive layer 50 have substantially the same width dimension, but the present invention is not limited thereto, and the width dimension of the first adhesive layer 50 may be larger than the width dimension of the insulating layer 30. In this case, it may be possible to reduce stress generated in the stretchable device 100 due to the difference in the width dimensions of the two layers, compared to a case in which the width dimensions of the two layers are substantially the same.

[0033] (Characteristic parts of the first embodiment) The following describes the characteristic parts of the first embodiment, taking into account the main components of the stretchable device 100. The first embodiment is characterized in that the first adhesive layer 50 has a relatively smaller stretch performance (or stretchability or stretch rate) than the insulating layer 30, on the premise that the first adhesive layer 50 overlaps at least a part of the insulating layer 30 in the thickness direction X of the stretchable substrate.

[0034] In this specification, the term "stretchability performance (or stretchability or stretch rate)" refers, in a broad sense, to the properties and ability of stretching of the adhesive layer (first adhesive layer / second adhesive layer described below) and insulating layer, which are components of a stretchable device, and, in a narrow sense, to something that can be evaluated based on the difference in Young's modulus and / or the difference in thickness of each of these adhesive layer and insulating layer.

[0035] In addition, in this specification, "low stretch performance" refers to a state in which stretching is difficult, and refers to a state in which the Young's modulus is large and / or the thickness is large. That is, the larger the Young's modulus, the more difficult it is to stretch, and the larger the thickness, the more difficult it is to stretch, and this state is defined as having low stretch performance. On the other hand, in this specification, a state in which stretching is easy, that is, a state in which the Young's modulus is small and / or a state in which the thickness is small, can be defined as having high stretch performance.

[0036] As an example, the Young's modulus of the first adhesive layer 50 is greater than the Young's modulus of the insulating layer 30. In the first embodiment, the width dimension of the first adhesive layer 50 and the width dimension of the insulating layer 30 are identical or substantially identical to each other. Furthermore, the thickness direction dimension of the stretchable substrate 10 of the first adhesive layer 50 and the thickness direction dimension of the stretchable substrate 10 of the insulating layer 30 are also identical or substantially identical to each other. That is, the cross-sectional area of ​​the first adhesive layer 50 and the cross-sectional area of ​​the insulating layer 30 can be identical or substantially identical to each other.

[0037] According to the above-mentioned feature, since the first adhesive layer 50 has a relatively smaller stretchability than the insulating layer 30, the first adhesive layer 50 can have a relatively harder property than the insulating layer 30. Therefore, when the stretchable device 100 stretches, the first adhesive layer 50 located at the wiring overlapping portion 70 of both the stretchable wirings 20, 40 is difficult to stretch. Accordingly, the localized portions of both the stretchable wirings 20, 40 located at the mutually overlapping portions with this difficult-to-stretch first adhesive layer 50 also become difficult to stretch.

[0038] This also makes it difficult for the insulating layer 30 located in the wiring overlap portion 70 between the first stretchable wiring 20 and the second stretchable wiring 40 to stretch. As a result, compared to the conventional embodiment (see FIGS. 16 and 17) in which the thickness of the insulating layer 30' may become thinner when stretched compared to before stretching of the stretchable device 100', it is possible to suppress a reduction in the thickness of the insulating layer 30 before and after stretching of the stretchable device 100 (see FIGS. 3 and 4).

[0039] As a result, by suppressing the reduction in the thickness of the insulating layer 30, it is possible to suppress a decrease in IR (insulation resistance) between the two elastic wires 20, 40. In other words, it is possible to suppress the occurrence of leakage voltage (or leakage current) between the two elastic wires 20, 40.

[0040] This makes it possible to suitably suppress the occurrence of a voltage drop (e.g., 5 V to 4 V) in one of the two stretchable wires 20, 40 when the device is stretched and contracted, and an accompanying voltage increase (e.g., 0 V to 1 V) in the other of the two stretchable wires 20, 40. This makes it possible to stabilize the voltage of the two stretchable wires 20, 40 when the device is stretched and contracted, and makes it possible to stabilize the voltage supply to the functional components.

[0041] Therefore, according to the first embodiment, it is possible to maintain the functions of the device, such as sensing and signal communication. Furthermore, when the device is driven under high humidity and high temperature, it is possible to avoid the occurrence of short circuits due to ion migration and wire contact at the wire overlapping portion 70 (for example, the wire intersection portion) of both wires where the voltage difference between both stretchable wires becomes large when the wires stretch.

[0042] Moreover, from the viewpoint of suppressing the occurrence of ion migration, it is preferable that the first stretchable wire 20 and the second stretchable wire 40 have different electric potentials. Furthermore, according to the first embodiment, since the insulating layer 30 is merely located in the overlapping portion 70 between the first stretchable wire 20 and the second stretchable wire 40, a gap can be provided between the adherend 300 such as a living body and the stretchable substrate 10. This can also improve the breathability of the stretchable device 100.

[0043] Above, the state of the stretchable device before and during stretching was explained using Figures 3 and 4. Hereinafter, we will clearly note that a modified example of the first embodiment and the second to fifth embodiments will be explained using drawings showing the state of the stretchable device during stretching.

[0044] In addition, two or more first adhesive layers 50 having different stretchability may be provided, provided that the stretchability is relatively smaller than that of the insulating layer 30. In this case, a first adhesive layer that is relatively harder (super hard) and a first adhesive layer that is relatively harder (hard) than the insulating layer 30 may be provided. For example, a structure in which two first adhesive layers are laminated, or a structure in which two first adhesive layers are arranged side by side in the width direction may be used.

[0045] [Modification 1 of the first embodiment] Hereinafter, the configuration of Modification 1 of the stretchable device according to the first embodiment will be described with reference to Fig. 5. Modification 1 of the first embodiment is different from the first embodiment (see Figs. 3 and 4) in the form of the first adhesive layer 50A.

[0046] FIG. 5 is a partially enlarged schematic cross-sectional view of Modification 1 of the stretchable device according to the first embodiment of the present invention (corresponding to the cross-sectional view taken along line XX in FIG. 2).

[0047] 5, the thickness of the first adhesive layer 50A is greater than the thickness of the insulating layer 30. In this case, the Young's modulus of the first adhesive layer 50A is smaller than the Young's modulus of the insulating layer 30. That is, a first adhesive layer 50A that is relatively softer and thicker than the first adhesive layer 50 shown in FIGS. 3 and 4 may be used. In addition, it is preferable that the width of the first adhesive layer 50A is greater than the width of the insulating layer 30.

[0048] By adopting such a configuration, the first adhesive layer 50A can provide a relatively smaller stretchability than the insulating layer 30. This makes it difficult for the insulating layer 30 located in the overlapping portion between the first stretchable wiring 20 and the second stretchable wiring 40 to stretch. As a result, a reduction in the thickness of the insulating layer 30 before and after stretching of the stretchable device 100A is suppressed, and thereby a decrease in IR (insulation resistance) between the two stretchable wirings 20, 40 can be suppressed.

[0049] It goes without saying that if the first adhesive layer 50A has relatively smaller elasticity than the insulating layer 30, the Young's modulus of the first adhesive layer 50A may be greater than the Young's modulus of the insulating layer 30.

[0050] [Modification 2 of the First Embodiment] Hereinafter, the configuration of the modified example 2 of the stretchable device according to the first embodiment will be described with reference to Fig. 6. The modified example 2 of the first embodiment is different from the first embodiment (see Figs. 3 and 4) in the location where the first adhesive layer 50B is disposed.

[0051] FIG. 6 is a partially enlarged schematic cross-sectional view of Modification 2 of the stretchable device according to the first embodiment of the present invention (corresponding to the cross-sectional view taken along line XX in FIG. 2).

[0052] As shown in FIG. 6, in the second variant, the stretchable device 100B may further include a protective layer 60. The second elastic wire 40 has a first side 41 facing the insulating layer and a second side 42 opposite to the first side 41. In this case, from the viewpoint of ensuring biocompatibility and insulation and waterproofing, it is preferable that the protective layer 60 contacts the second side 42 of the second elastic wire 40. Also, as shown in FIG. 6, in one example, the protective layer 60 can be disposed so as to contact the first elastic wire 20. However, without being limited thereto, a gap may be provided between the protective layer 60 and the first elastic wire 20 in a cross-sectional view.

[0053] In view of the above, the protective layer 60 may be made of a resin material having elasticity. For example, the protective layer 60 may be made of a polyester resin, a styrene resin, an olefin resin, an epoxy resin, a urethane resin, an acrylic resin, or a silicone resin.

[0054] In this configuration, the first adhesive layer 50B can be positioned between the protective layer 60 and the adherend 300, such as a living body. That is, compared to the first adhesive layer 50 shown in Figures 3 and 4, the first adhesive layer 50B in Modification 2 can be positioned between the protective layer 60 and the adherend 300, such as a living body, rather than the stretchable substrate 10. Note that, like the first adhesive layer 50 shown in Figures 3 and 4, the first adhesive layer 50B in Modification 2 is also premised on providing a stretchability performance that is relatively smaller than that of the insulating layer 30.

[0055] As a result, in the second modified example, the insulating layer 30 located in the overlapping portion between the first stretchable wiring 20 and the second stretchable wiring 40 is also less likely to stretch. As a result, a reduction in the thickness of the insulating layer 30 before and after stretching of the stretchable device 100B is suppressed, and thereby a decrease in IR (insulation resistance) between the two stretchable wirings 20, 40 can be suppressed.

[0056] In the first embodiment and its modified examples 1 and 2, the thickness of the first adhesive layer 50 is preferably constant from the viewpoint of favorably adhering to both the stretchable substrate 10 and the adherend 300 such as a living body. As described above, the first adhesive layer 50 can be provided with a characteristic that it is relatively harder than the insulating layer 30 by adjusting the properties (Young's modulus) of the first adhesive layer 50 itself and the thickness of the first adhesive layer 50 itself. That is, the first adhesive layer 50 is technically different from the previous embodiment in that it can be provided with a characteristic that it is relatively harder than the insulating layer 30 even if it does not have a separate reinforcing member inside.

[0057] [Second embodiment] Hereinafter, the configuration of the stretchable device according to the second embodiment will be described with reference to Fig. 7. Compared with the first embodiment (see Figs. 3 and 4), the second embodiment differs in that it uses at least two types of adhesive layers.

[0058] FIG. 7 is a partially enlarged schematic cross-sectional view of a stretchable device according to a second embodiment of the present invention (corresponding to the cross-sectional view taken along line XX in FIG. 2).

[0059] In the second embodiment, a second adhesive layer 52C is further used in addition to the first adhesive layer 51C. Specifically, as shown in Fig. 7, the second adhesive layer 52C faces at least one side of the first adhesive layer 51C in a cross-sectional view, and may have a Young's modulus different from that of the first adhesive layer 51C.

[0060] In addition, compared with the properties of the insulating layer 30, the second adhesive layer 52C may have a relatively smaller elasticity performance than the insulating layer 30. For example, the second adhesive layer 52C may have a relatively smaller Young's modulus than the insulating layer 30.

[0061] According to this configuration, compared to the first embodiment, the first adhesive layer 51C and the second adhesive layer 52C can be arranged in parallel adjacent to each other. This can increase the proportion of the adhesive layer in the region between the stretchable substrate 10 and the adherend 300 such as a living body. In addition, the thickness of the region between the stretchable substrate 10 and the adherend 300 such as a living body can be made uniform as a whole when the stretchable device 100 stretches.

[0062] As a result, compared to the case where only the first adhesive layer in the first embodiment is disposed, in a cross-sectional view, it is possible to suppress unintentional local curvature or bending of the stretchable device 100C (specifically, the stretchable substrate 10, the stretchable wiring 20, 40) toward the adherend 300 during stretching on at least one side of the first adhesive layer 51C. As a result, it is possible to improve the strength of the stretchable device 100C as a whole.

[0063] From the viewpoint of further improving the uniformity of the thickness of the region between the stretchable substrate 10 and the adherend 300 such as a living body during stretching, it is preferable that the second adhesive layer 52C contacts the first adhesive layer 51C as shown in Fig. 7. Without being limited thereto, in another example, the first adhesive layer and the second adhesive layer 52 may be arranged to be spaced apart from each other and to face each other as shown in a modified example described later.

[0064] [Modification 1 of the second embodiment] Hereinafter, the configuration of the modified example 1 of the stretchable device according to the second embodiment will be described with reference to Fig. 8. The modified example 1 of the second embodiment is different from the second embodiment (see Fig. 7) in the width dimension of the first adhesive layer.

[0065] FIG. 8 is a partially enlarged schematic cross-sectional view of Modification 1 of the stretchable device according to the second embodiment of the present invention (corresponding to the cross-sectional view taken along line XX in FIG. 2).

[0066] 8, in a cross-sectional view, the width of the first adhesive layer 51D is smaller than the width of the insulating layer 30. In other words, the first adhesive layer 51D and the second adhesive layer 52D may overlap with the insulating layer 30 in the thickness direction X of the elastic substrate 10.

[0067] According to this configuration, since the width of the first adhesive layer 51D is smaller than the width of the insulating layer 30, it is possible to suppress stress concentration on the first adhesive layer 51D, which has a relatively rigid property, when the stretchable device 100D stretches or contracts.

[0068] In other words, when the stretchable device 100D shown in FIG. 7 stretches or contracts, the stress applied to the first adhesive layer 51D, which has relatively hard properties, can be alleviated compared to when the width of the first adhesive layer 51C and the width of the insulating layer 30 are the same or substantially the same, as shown in FIG.

[0069] When the width of the first adhesive layer and the width of the insulating layer are the same or substantially the same, the points of stress concentration in the stretchable device may be the interface between the first adhesive layer and a component in contact with it in the width direction, and the interface between the insulating layer and a component in contact with it in the width direction.

[0070] In contrast, in this embodiment, the first adhesive layer 51D and the second adhesive layer 52D overlap with the insulating layer 30 in the thickness direction X of the stretchable substrate 10, and therefore, due to the relatively soft insulating layer 30, the influence of the first adhesive layer 51D, which has hard properties, is strong in the overlapping region between the first adhesive layer 51D and the insulating layer 30 in the thickness direction X of the stretchable substrate 10. The influence of the second adhesive layer 52D, which has hard properties, is strong in the overlapping region between the second adhesive layer 52D and the insulating layer 30. In the thickness direction X of the stretchable substrate 10, in the region where the second adhesive layer 52D and the insulating layer 30 do not overlap, the influence of the second adhesive layer 52D acts.

[0071] From the above, by increasing the Young's modulus of the second adhesive layer 52D, the insulating layer 30, and the first adhesive layer 51D in that order, the ease of stretching can be gradually changed, thereby making it possible to further reduce stress in the stretchable device.

[0072] [Modification 2 of the second embodiment] Hereinafter, the configuration of Modification 2 of the stretchable device according to the second embodiment will be described with reference to Fig. 9. Modification 2 of the second embodiment differs from the second embodiment and its Modification 1 (see Figs. 7 and 8) in the arrangement of the first adhesive layer 51E and the second adhesive layer 52E.

[0073] FIG. 9 is a partially enlarged schematic cross-sectional view of Modification 2 of the stretchable device according to the second embodiment of the present invention (corresponding to the cross-sectional view taken along line XX in FIG. 2).

[0074] Specifically, in a cross-sectional view, the second adhesive layer 52E can be separated from the first adhesive layer 51E. With this configuration, it is possible to improve the uniformity of the thickness of the region between the stretchable substrate 10 and the adherend 300 such as a living body when the stretchable device 100E is stretched or contracted by arranging the first adhesive layer 51E and the second adhesive layer 52E in parallel. In addition, since a gap (corresponding to a physical space) can be provided by arranging the second adhesive layer 52E and the first adhesive layer 51E at a distance, it is also possible to improve the breathability between the adherend 300 such as a living body and the stretchable substrate 10.

[0075] [Third embodiment] Hereinafter, the configuration of a stretchable device according to the third embodiment will be described with reference to Fig. 10 and Fig. 11. Compared to the first embodiment (see Fig. 3 and Fig. 4), the third embodiment differs in that there are a plurality of wiring overlapping portions 70F.

[0076] Fig. 10 is a plan view showing a stretchable device according to a third embodiment of the present invention, Fig. 11 is a partially enlarged schematic cross-sectional view of the stretchable device according to the third embodiment of the present invention taken along line segment YY in Fig. 10.

[0077] As shown in Fig. 10, the third embodiment is premised on the existence of a plurality of wiring overlapping portions 70F. In this specification, each of the plurality of elastic wirings overlapping with the first elastic wiring 20 corresponds to the above-mentioned second elastic wirings 41 to 43.

[0078] In this case, the first adhesive layer 50F may overlap the insulating layer 30F at the multiple wiring overlapping portions 70F in the thickness direction X of the elastic substrate as shown in Fig. 11. In one example, the insulating layer 30F and the first adhesive layer 50F overlapping the insulating layer 30F may be positioned at each of the multiple wiring overlapping portions 70F as shown in Fig. 11.

[0079] As in the first embodiment, in the third embodiment, each first adhesive layer 50F overlaps with the insulating layer 30 in the thickness direction X of the stretchable substrate 10, and has a stretching performance relatively smaller than that of each insulating layer 30F. According to this configuration, the insulating layer 30 located in each wiring overlapping portion 70F is also less likely to stretch, so that it is possible to suppress a reduction in the thickness of each insulating layer 30F before and after stretching of the stretchable device 100F (see FIGS. 10 and 11) compared to the previous embodiment (see FIGS. 16 and 17).

[0080] From the above, even when there are a plurality of wiring overlapping portions 70F, by suppressing the reduction in the thickness of each insulating layer 30F, it is possible to suppress the decrease in IR (insulation resistance) between the elastic wirings 20, 40 in each wiring overlapping portion 70F. In other words, it is possible to suppress the occurrence of leakage current between the elastic wirings 20, 40 in each wiring overlapping portion 70F.

[0081] In addition, in the third embodiment, since a plurality of first adhesive layers 50F can be arranged at predetermined intervals, a plurality of gaps can be formed at predetermined intervals between the adherend 300 such as a living body and the stretchable substrate 10. This can improve the breathability between the adherend 300 such as a living body and the stretchable substrate 10.

[0082] [Fourth embodiment] Hereinafter, the configuration of a stretchable device according to the fourth embodiment will be described with reference to Fig. 12 and Fig. 13. Compared with the third embodiment (see Fig. 10 and Fig. 11), the fourth embodiment differs in that one insulating layer and one first adhesive layer are positioned so as to span a plurality of wiring overlapping portions.

[0083] Fig. 12 is a plan view showing a stretchable device according to a fourth embodiment of the present invention. Fig. 13 is a partially enlarged schematic cross-sectional view showing the stretchable device according to the fourth embodiment of the present invention taken along line segment ZZ in Fig. 12.

[0084] As shown in FIGS. 12 and 13, in the fourth embodiment, one insulating layer 30G spanning a plurality of wiring overlapping portions 70G and a first adhesive layer 50G overlapping the one insulating layer 30G may be positioned.

[0085] According to this configuration, in comparison with the third embodiment, when manufacturing a stretchable device 100G including a plurality of wiring overlapping portions 70G, the material of the first adhesive layer can be continuously supplied at once to the main surface of the stretchable substrate 10. Furthermore, the material of the insulating layer can be continuously supplied at once to the main surface of the first stretchable wiring 20.

[0086] As described above, the manufacturing process of the stretchable device 100G including a plurality of wiring overlapping portions 70G can be simplified, and therefore the manufacturing efficiency of the stretchable device 100G according to the fourth embodiment can be improved.

[0087] Furthermore, in the fourth embodiment, one insulating layer 30G is disposed so as to straddle a plurality of wiring overlapping portions 70G, and therefore it is possible to more suitably suppress contact between the first elastic wiring 20 and each of the second elastic wirings 41 to 43. This makes it possible to more suitably suppress the occurrence of ion migration and the occurrence of short circuits.

[0088] Furthermore, in the fourth embodiment, one first adhesive layer 50G is positioned so as to straddle a plurality of wiring overlapping portions 70G, so that the area of ​​the first adhesive layer 50G between the adherend 300, such as a living body, and the stretchable substrate 10 can be made larger. This increases the connection strength with the stretchable substrate 10, The strength of the stretchable device 100G can be improved. In addition, the adhesive area to the adherend 300 such as a living body is increased, making it easier to hold the stretchable device 100G to the adherend 300 such as a living body.

[0089] [Fifth embodiment] Hereinafter, the configuration of a stretchable device according to the fifth embodiment will be described with reference to Fig. 14 and Fig. 15. Compared with the first embodiment (see Figs. 1 to 4), the fifth embodiment differs in that an electronic component is mounted on the stretchable device.

[0090] Fig. 14 is a plan view showing a stretchable device according to a fifth embodiment of the present invention. Fig. 15 is a partially enlarged schematic cross-sectional view showing the stretchable device according to the fifth embodiment of the present invention taken along line segment WW in Fig. 14.

[0091] 14 and 15, in the fifth embodiment, an electronic component 200 is mounted, and the electronic component 200 overlaps with the first adhesive layer 50H in the thickness direction X of the stretchable substrate 10. The electronic component 200 is connected to the first stretchable wiring 20 via the land 210.

[0092] By adopting such a configuration, in the fifth embodiment, the first adhesive layer 50H overlaps with the electronic component 200 in addition to the insulating layer 30 in the thickness direction X of the stretchable substrate 10, and has a relatively smaller stretching performance than the insulating layer 30F. Therefore, both the insulating layer 30F and the land 210 overlapping with the first adhesive layer 50H are difficult to stretch. This makes it possible to suppress a decrease in IR between the stretchable wirings 20 and 40 in the wiring overlapping portion 70 by suppressing a reduction in the thickness of the insulating layer 30F before and after the stretchable device 100H is stretched. In addition, it is possible to suppress disconnection of the electronic component 200 connected to the stretchable device 100H via the land 210 before and after the stretchable device 100H is stretched (see FIG. 14 and FIG. 15).

[0093] In addition, when an electronic component is mounted on a stretchable device, a process of adding a resin material to cover the electronic component 200 and the land 210 (potting process) may usually be required from the standpoint of preventing expansion and contraction of the land 210 when the device expands and contracts, and protecting the electronic component 200 connected to the land 210.

[0094] In this regard, as described above, in the fifth embodiment, the expansion and contraction of the land 210 before and after the expansion and contraction of the stretchable device 100H and the associated disconnection of the electronic component 200 can be suppressed. Therefore, the potting process described above is not required. By not requiring the implementation of such a process, it is possible to prevent the occurrence of chemical attack and reduce the height of the electronic component 200.

[0095] Note that each embodiment and modification is an example, and the present invention is not limited to each embodiment and modification. Also, each drawing is an example of components, and does not limit the shape. Also, partial replacement or combination of the configurations shown in different embodiments and modifications is possible.

[0096] The stretchable device according to one embodiment of the present invention may have the following features. <1> A stretchable device comprising: a stretchable substrate; a first stretchable wiring and a second stretchable wiring provided on the stretchable substrate and partially overlapping each other in a thickness direction of the stretchable substrate; an insulating layer disposed in a wiring overlap portion between the first stretchable wiring and the second stretchable wiring; and a first adhesive layer overlapping at least a portion of the insulating layer in the thickness direction, wherein the first adhesive layer has a stretchability relatively smaller than that of the insulating layer. <2> In the wiring overlap portion, the first elastic wiring and the second elastic wiring intersect with each other. <1> 2. The stretchable device according to claim 1 . <3> The Young's modulus of the first adhesive layer is greater than the Young's modulus of the insulating layer. <1> or <2> 2. The stretchable device according to claim 1 . <4> The first adhesive layer is located between the stretchable substrate and the adherend. <1> ~ <3> 2. The stretchable device according to any one of claims 1 to 11. <5> Further comprising a protective layer, the second elastic wiring has a first side facing the insulating layer and a second side opposite to the first side, the protective layer contacts the second side, and the first adhesive layer is located between the protective layer and the adherend, <1> ~ <4> 2. The stretchable device according to any one of claims 1 to 11. <6> The second adhesive layer is further provided, the second adhesive layer being opposed to at least one side of the first adhesive layer in a cross-sectional view and having a different Young's modulus from that of the first adhesive layer. <1> ~ <5> 2. The stretchable device according to any one of claims 1 to 11. <7> The second adhesive layer has a relatively smaller elasticity than the insulating layer. <6> 2. The stretchable device according to claim 1 . <8> The Young's modulus of the second adhesive layer is smaller than the Young's modulus of the insulating layer. <6> or <7> 2. The stretchable device according to claim 1 . <9> The second adhesive layer is spaced apart from the first adhesive layer. <6> ~ <8> 2. The stretchable device according to any one of claims 1 to 11. <10> The second adhesive layer is in contact with the first adhesive layer. <6> ~ <9> 2. The stretchable device according to any one of claims 1 to 11. <11> The second adhesive layer overlaps with the insulating layer in the thickness direction of the elastic base material. <6> ~ <10> 2. The stretchable device according to any one of claims 1 to 11. <12> In a cross-sectional view, the width of the first adhesive layer is smaller than the width of the insulating layer; <11> 2. The stretchable device according to claim 1 . <13> There are a plurality of the wiring overlapping portions, and the insulating layer and the first adhesive layer overlapping the insulating layer are positioned at each of the plurality of wiring overlapping portions in the thickness direction of the stretchable substrate. <1> ~ <12> 2. The stretchable device according to any one of claims 1 to 11. <14> There are a plurality of the wiring overlapping portions, and one of the insulating layers spanning the plurality of wiring overlapping portions and the first adhesive layer overlapping the one insulating layer are positioned in the thickness direction of the stretchable substrate. <1> ~ <13> 2. The stretchable device according to any one of claims 1 to 11. <15> The thickness of the first adhesive layer is greater than the thickness of the insulating layer. <1> ~ <14> 2. The stretchable device according to any one of claims 1 to 11. <16> When the thickness of the first adhesive layer is greater than the thickness of the insulating layer, the Young's modulus of the first adhesive layer is smaller than the Young's modulus of the insulating layer. <15> 2. The stretchable device according to claim 1 . <17> In a cross-sectional view, the width of the first adhesive layer is larger than the width of the insulating layer. <16> 2. The stretchable device according to claim 1 . <18> An electronic component can be mounted on the elastic substrate, and the electronic component overlaps the first adhesive layer in the thickness direction of the elastic substrate. <1> ~ <17> 2. The stretchable device according to any one of claims 1 to 11. <19> The first elastic wiring and the second elastic wiring have different electric potentials. <1> ~ <18> 2. The stretchable device according to any one of claims 1 to 11. <20> The thickness of the first adhesive layer is constant. <1> ~ <19> 2. The stretchable device according to any one of claims 1 to 11.

[0097] 300 Adherend 300 (living body, etc.) 200, 201, 202 Electronic components 100, 100A~100H, 100' Elastic device vinegar 10, 10' elastic base material 20, 20' 1st elastic wiring 30, 30F, 30G, 30' Insulation layer 40, 40', 41~43 2nd elastic wiring 50, 50A, 50B, 51C, 51D, 51E, 50F, 50G, 50H, 50' 1st adhesive layer 52C, 52D, 52E 2nd adhesive layer 60 protective layer 70, 70F, 70G Wiring overlapping area X: thickness direction of elastic substrate

Claims

1. A stretchable device comprising: a stretchable substrate; a first stretchable wiring and a second stretchable wiring provided on the stretchable substrate and partially overlapping each other in a thickness direction of the stretchable substrate; an insulating layer disposed in a wiring overlap portion between the first stretchable wiring and the second stretchable wiring; and a first adhesive layer overlapping at least a portion of the insulating layer in the thickness direction, the first adhesive layer having a relatively smaller stretchability than the insulating layer, and being composed of an adhesive.

2. The stretchable device according to claim 1 , wherein the first stretchable wiring and the second stretchable wiring intersect with each other in the wiring overlap portion.

3. The stretchable device of claim 1 , wherein the Young's modulus of the first adhesive layer is greater than the Young's modulus of the insulating layer.

4. The stretchable device according to claim 1 , wherein the first adhesive layer is located between the stretchable substrate and an adherend.

5. The stretchable device according to claim 1, further comprising a protective layer, wherein the second stretchable wiring has a first side facing the insulating layer and a second side opposite the first side, the protective layer contacts the second side, and the first adhesive layer is located between the protective layer and an adherend.

6. The stretchable device of claim 1, further comprising a second adhesive layer, the second adhesive layer facing at least one side of the first adhesive layer in a cross-sectional view and having a Young's modulus different from that of the first adhesive layer.

7. The stretchable device according to claim 6 , wherein the second adhesive layer has a relatively smaller stretchability than the insulating layer.

8. The stretchable device of claim 7 , wherein the second adhesive layer has a Young's modulus smaller than the Young's modulus of the insulating layer.

9. The stretchable device of claim 6 , wherein the second adhesive layer is spaced apart from the first adhesive layer.

10. The stretchable device of claim 6 , wherein the second adhesive layer contacts the first adhesive layer.

11. The stretchable device according to claim 6 , wherein the second adhesive layer overlaps with the insulating layer in a thickness direction of the stretchable substrate.

12. 12. The stretchable device of claim 11, wherein in a cross-sectional view, a width of the first adhesive layer is smaller than a width of the insulating layer.

13. 2. The stretchable device according to claim 1, wherein there are a plurality of wiring overlapping portions, and the insulating layer and the first adhesive layer overlapping the insulating layer are positioned at each of the plurality of wiring overlapping portions in the thickness direction of the stretchable substrate.

14. The stretchable device according to claim 1, wherein there are a plurality of wiring overlapping portions, and in the thickness direction of the stretchable substrate, one insulating layer spanning the plurality of wiring overlapping portions and the first adhesive layer overlapping the one insulating layer are positioned.

15. The stretchable device of claim 1 , wherein a thickness of the first adhesive layer is greater than a thickness of the insulating layer.

16. The stretchable device according to claim 15 , wherein when a thickness of the first adhesive layer is greater than a thickness of the insulating layer, the Young's modulus of the first adhesive layer is smaller than the Young's modulus of the insulating layer.

17. 17. The stretchable device of claim 16, wherein, in a cross-sectional view, a width of the first adhesive layer is greater than a width of the insulating layer.

18. The stretchable device according to claim 1 , wherein an electronic component can be mounted thereon, and the electronic component overlaps the first adhesive layer in a thickness direction of the stretchable substrate.

19. The stretchable device according to claim 1 , wherein the first stretchable wire and the second stretchable wire have different electric potentials.

20. The stretchable device of claim 1 , wherein the first adhesive layer has a constant thickness.

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