Elastic property wiring board

Abstract

To provide an elastic property wiring board having a structure that an electrode and an external terminal part are exposed to the same surface of an elastic property wiring board, and capable of more easily realizing a structure with good connection reliability.SOLUTION: An elastic property wiring board 100 comprises: a first elastic property base material 10 in which a first elastic property conductive patter 20 containing an electrode 22 is formed to one main surface 10a; a reinforcement base material 50 in which an external side wiring pattern 60 containing an external terminal part 62 and a connection part is formed to one main surface 10a; and a second elastic property base material 30 in which a second elastic property conductive pattern 40 is formed to the one main surface 10a. The second elastic property base material 30 is laminated to the first elastic property base material 10 and the reinforcement base material 50, the first elastic property conductive patter 20 and the connection part are alternately electrically connected via the second elastic property conductive pattern 40. The electrode 22 and the external terminal part 62 are exposed to the same surface of the elastic property wiring board.SELECTED DRAWING: Figure 2

Description

Technical Field

[0001] The present invention relates to a stretchable wiring board.

Background Art

[0002] The stretchable wiring board is used by being attached to the target surface of an object, and an external device is attached to the surface on the opposite side of the object side in the stretchable wiring board. Depending on the type, shape, etc. of the object and the external device, a stretchable wiring board having a structure in which the electrode and the external terminal portion are exposed on the same surface of the stretchable wiring board is preferable. As a stretchable wiring board in which the electrode and the external terminal portion are exposed on the same surface, for example, there is one described in Patent Document 1. The stretchable wiring board of Patent Document 1 includes a stretchable base material in which an electrode (described as an electrode pattern in the same document) is formed on one main surface, and an external side wiring pattern (described as an external terminal in the same document) including an external terminal portion and a connection portion. A reinforcing base material (described as a flexible film in the same document) is formed on one main surface, and the wiring portion that electrically connects the electrode and the connection portion to each other is formed directly across the first stretchable base material and the reinforcing base material.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the stretchable wiring board described in Patent Document 1, there is still room for improvement from the viewpoint of easily realizing good connection reliability of the stretchable wiring board.

Means for Solving the Problems

[0005] According to the present invention, a first stretchable base material having a first stretchable conductor pattern including electrodes formed on one main surface, a reinforcing base material having an external side wiring pattern including an external terminal portion and a connection portion formed on one main surface, a second stretchable base material having a second stretchable conductor pattern formed on one main surface, A stretchable wiring board comprising: The second stretchable base material is laminated on the first stretchable base material and the reinforcing base material, and the first stretchable conductor pattern and the connection portion are electrically connected to each other via the second stretchable conductor pattern. There is provided a stretchable wiring board in which the electrode and the external terminal portion are exposed on the same surface of the stretchable wiring board.

Effect of the Invention

[0006] According to the present invention, it is possible to more easily realize a stretchable wiring board having a structure in which an electrode and an external terminal portion are exposed on the same surface of the stretchable wiring board and having excellent connection reliability.

Brief Description of the Drawings

[0007]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Embodiments for Carrying Out the Invention

[0008] Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 6. In all the drawings, the same reference numerals are assigned to the same components, and the description will be omitted as appropriate.

[0009] As shown in FIGS. 1 and 2, the stretchable wiring substrate 100 according to the present embodiment includes a first stretchable base material 10 on one main surface 10a of which a first stretchable conductor pattern 20 including an electrode 22 is formed, a reinforcing base material 50 on one main surface 10a of which an external side wiring pattern 60 including an external terminal portion 62 and a connection portion 63 is formed, and a second stretchable base material 30 on one main surface 10a of which a second stretchable conductor pattern 40 is formed. The second stretchable base material 30 is laminated on the first stretchable base material 10 and the reinforcing base material 50, and the first stretchable conductor pattern 20 and the connection portion 63 are electrically connected to each other via the second stretchable conductor pattern 40, and the electrode 22 and the external terminal portion 62 are exposed on the same surface of the stretchable wiring substrate 100 (in the case of the present embodiment, the target surface side of the object to which the stretchable wiring substrate 100 is attached). Note that the state of being "exposed on the target surface side of the object" as used herein includes a state covered with a member peeled off during use of the stretchable wiring substrate 100 (for example, a second peeling film 76 described later), but does not include a state covered with a member that is not peeled off during use of the stretchable wiring substrate 100 (such as the first stretchable base material 10).

[0010] The stretchable wiring substrate 100 is used by being attached to the target surface of an object (for example, the skin of a living body), and an external device is attached to the surface of the stretchable wiring substrate 100 on the side opposite to the object side. The external terminal portion 62 is connected to an external device (not shown), and outputs, for example, an electrical signal detected by the electrode 22 to the external device. Here, from the viewpoint of realizing the fitness to the target surface of the object, the first stretchable base material 10 is a thin film sheet material having two main surfaces (one main surface 10a and the other main surface 10b). In a state where the stretchable wiring substrate 100 is attached to the target surface, the first stretchable base material 10 stretches and bends following the unevenness and deformation of the target surface. Further, the stretchable first stretchable conductor pattern 20 also deforms as the first stretchable base material 10 stretches and bends. On the other hand, the reinforcing base material 50 on which the external terminal portion 62 connected to a connector or the like (not shown) of the external device is formed is higher in rigidity and non-stretchable than the first stretchable base material 10 from the viewpoint of ensuring structural strength.

[0011] According to the present embodiment, the stretchable wiring substrate 100 includes a first stretchable base material 10 on which a first stretchable conductor pattern 20 including an electrode 22 is formed, a reinforcing base material 50 on which an external side wiring pattern 60 including an external terminal portion 62 and a connection portion 63 is formed, and a second stretchable base material 30 on which a second stretchable conductor pattern 40 is formed on one main surface. Then, the second stretchable base material 30 on which the second stretchable conductor pattern 40 is formed is laminated on the first stretchable base material 10 and the reinforcing base material 50, so that the first stretchable conductor pattern 20 and the connection portion 63 are electrically connected to each other via the second stretchable conductor pattern 40. According to such a configuration, since the second stretchable conductor pattern connecting the first stretchable conductor pattern 20 and the connection portion 63 is well supported by the second stretchable base material 30, the structural strength of the second stretchable conductor pattern 40 can be sufficiently ensured. Therefore, it is possible to more easily realize the stretchable wiring substrate 100 having a structure in which the electrode 22 and the external terminal portion 62 are exposed on the same surface of the stretchable wiring substrate 100 and having excellent connection reliability. Furthermore, according to the present embodiment, the second stretchable conductor pattern 40 can be pre-formed (e.g., printed) on the flat second stretchable substrate 30. Therefore, for example, compared with the case where the wiring portion (the second stretchable conductor pattern 40) connecting the electrode 22 and the external terminal portion 62 is printed across the reinforcing substrate 50 and the first stretchable substrate 10, it becomes easier to form the second stretchable conductor pattern 40 in a desired shape and range. Therefore, the corresponding electrodes 22 and the connection portions 63 can be more reliably and easily electrically connected to each other via the second stretchable conductor pattern 40.

[0012] In the case of the present embodiment, the stretchable wiring board 100 is used by being attached to the skin of a desired part of the living body. The skin is a curved surface having irregularities and deforms (stretches, etc.) as the muscles stretch or the joints bend. Note that the stretchable wiring board 100 is not limited to being used by being attached to the skin, and may be used by being attached to, for example, the nails of a living body, clothes, robots, various devices, apparatuses, and wearable articles.

[0013] The stretchable wiring board 100 may be used to acquire a biological signal from the skin of a living body via an external device (not shown), or may be used to transmit an electrical signal applied from an external device to the skin of a living body. More specifically, the external device is, for example, a biosensor that detects weak biological signals such as electroencephalogram, electromyogram, and electrocardiogram that detect biological information such as electrocardiogram, heart rate, blood pressure, and body temperature, a device that gives electrical stimulation (EMS: Electrical Muscle Stimulation) to the muscles of a living body, an acceleration sensor or a gyro sensor that detects the movement (acceleration) of a living body in multiple axes. Note that in the present invention, the stretchable wiring board 100 may be used by being connected to a device other than devices such as a power supply, a control board, and a monitor.

[0014] Hereinafter, when explaining the positional relationship between the components of the stretchable wiring board 100, the upper side in FIG. 2 is referred to as the upper side or the upper direction, etc., and the opposite side is referred to as the lower side or the lower direction, etc. Also, the left side in FIG. 2 is referred to as the left side or the left direction, etc., and the opposite side is referred to as the right side or the right direction, etc. However, these direction definitions are for convenience and do not limit the direction during the manufacturing or use of the stretchable wiring board 100.

[0015] As shown in any one of FIGS. 1 to 3, the stretchable wiring board 100 is a laminate formed in a flat plate shape or a sheet shape. More specifically, the stretchable wiring board 100 includes, for example, a first stretchable base material 10, a first stretchable conductor pattern 20, a second stretchable base material 30, a second stretchable conductor pattern 40, a reinforcing base material 50, and an external side wiring pattern 60, and further includes an adhesive layer 81, a first release film 71, and a second release film 76. In the case of this embodiment, the adhesive layer 81 is directly laminated under the first release film 71, and the second stretchable base material 30 is directly laminated under the adhesive layer 81. Also, the reinforcing base material 50 and the first stretchable base material 10 are laminated under the second stretchable base material 30, and the second release film 76 is directly laminated under the first stretchable base material 10.

[0016] As shown in FIG. 5, the first stretchable base material 10 is a thin film sheet material that can stretch in at least one direction in the in-plane direction. Here, the stretchability means that the first stretchable base material 10 stretches when a tensile force acts on it, and also shrinks in response to a compressive force. In the first stretchable base material 10, the change in dimensional shape due to stretching is larger than the change in dimensional shape due to shrinkage. In the case of this embodiment, as shown in FIGS. 1 and 5, the first stretchable base material 10 is formed, for example, in a substantially rectangular shape that is long in one direction in a plan view. In the following description, the longitudinal direction of the first stretchable base material 10 may be simply referred to as the longitudinal direction, and the short transverse direction of the first stretchable base material 10 may be simply referred to as the short transverse direction. Note that in the present invention, the planar shape of the first stretchable base material 10 is not limited to this example, and it may be formed, for example, in a perfect circular shape or an oval shape.

[0017] The material constituting the first stretchable substrate 10 is not particularly limited, and examples thereof include elastomeric materials such as nitrile rubber, latex rubber, and urethane-based elastomers. In particular, by using a urethane-based elastomer sheet used for medical purposes, high safety can be obtained even when attached to the human skin.

[0018] The thickness dimension of the first stretchable substrate 10 is not particularly limited, but from the viewpoint of not inhibiting the stretching movement of the skin, for example, it is preferably 50 μm or less, more preferably 5 μm or less. By doing so, the wearing feeling of the stretchable wiring board 100 is improved, and when the used stretchable wiring board 100 is peeled off from the skin, it is possible to suppress the temporary remaining of the adhesion marks of the stretchable wiring board 100 on the skin.

[0019] The first stretchable substrate 10 preferably has a maximum elongation rate of 10% or more, more preferably 50% or more, still more preferably 100% or more, and particularly preferably 200% or more. Here, the maximum elongation rate of the first stretchable substrate 10 means the maximum value of the elongation rate that can be elastically deformed in one direction in the in-plane direction. In this embodiment, the elongation rate means the ratio of elongation in one direction in the in-plane direction when a force is applied with respect to the dimension (elongation rate 0% dimension) when no external force is applied. For example, if the elongation rate is 50%, it is an elongation rate 1.5 times the elongation rate 0% dimension, and if the elongation rate is 100%, it is an elongation rate 2 times the elongation rate 0% dimension.

[0020] As shown in FIG. 2, the second stretchable substrate 30 is laminated on one main surface 10a of the first stretchable substrate 10 and covers the formation region of the first stretchable conductor pattern 20. In other words, the second stretchable substrate 30 also serves as a cover member for protecting the first stretchable conductor pattern 20. Therefore, while sufficiently ensuring the structural strength of the first stretchable conductor pattern 20, the manufacturing cost and man-hours of the stretchable wiring board 100 can be reduced. More specifically, the second stretchable base material 30 includes, for example, a portion indirectly laminated on one main surface 10a of the first stretchable base material 10 via the reinforcing base material 50 or the first stretchable conductor pattern 20, and a portion directly laminated on one main surface 10a of the first stretchable base material 10.

[0021] The second stretchable base material 30 is set to have, for example, the same shape and the same dimensions as the first stretchable base material 10. In plan view, the second stretchable base material 30 covers the entire first stretchable base material 10. However, in the present invention, the second stretchable base material 30 may locally cover a part of the first stretchable base material 10. However, in the present invention, the shape and dimensions of the second stretchable base material 30 are not limited to this example, and may be set to have a different shape and different dimensions from the first stretchable base material 10, for example, as in the modification examples described later.

[0022] The material constituting the second stretchable base material 30 is not particularly limited, but is, for example, an elastomer material similar to the first stretchable base material 10. However, the second stretchable base material 30 only needs to be made of a material having at least insulation and stretchability, and may be made of a material different from the first stretchable base material 10. The thickness dimension of the second stretchable base material 30 is not particularly limited, but from the viewpoint of not hindering the stretching movement of the skin, it is preferably, for example, 50 μm or less, more preferably 5 μm or less.

[0023] The first stretchable conductor pattern 20 has conductivity and can transmit electrical signals and currents. More specifically, in the case of the present embodiment, the electrode 22 of the first stretchable conductor pattern 20 is a biological electrode disposed on the side of the living body's skin. Through the electrode 22, an external device can acquire biological signals such as electroencephalogram, electromyogram, and electrocardiogram from the living body. The first stretchable conductor pattern 20 is deformable following the stretching of the first stretchable base material 10. In the case of this embodiment, the first stretchable conductor pattern 20 includes the above-described electrode 22 and an electrode connection portion 23 that is connected to the electrode 22 and covered with the second stretchable base material 30. More specifically, the first stretchable conductor pattern 20 includes, for example, a plurality of electrodes 22 and a plurality (for example, the same number as the plurality of electrodes 22) of electrode connection portions 23. One electrode connection portion 23 is connected to one electrode 22. The plurality of (for example, three) electrodes 22 include, for example, electrodes 22a and 22b, and an electrode 22c disposed at a position offset from a line segment (virtual line 401 shown in FIG. 1) connecting the electrode 22a and the electrode 22b. More specifically, the electrode 22c is disposed on the side opposite to the external terminal portion 62 side with respect to the virtual line 401 connecting the electrode 22a and the electrode 22b in the longitudinal direction. Further, the electrodes 22a, 22b, and 22c are arranged in this order from one side in the short hand direction (in the case of this embodiment, the upper side in FIG. 1). Each of the plurality of electrodes 22 (electrodes 22a to 22c) is set to have the same shape and the same dimensions as each other. In the case of this embodiment, as an example, the planar shape of the electrode 22 is a perfect circle shape. The plurality of electrode connection portions 23 include, for example, an electrode connection portion 23a connected to the electrode 22a, an electrode connection portion 23b connected to the electrode 22b, and an electrode connection portion 23c connected to the electrode 22c.

[0024] Here, as shown in FIGS. 1 and 6, the electrode connection portion 23 of the first stretchable base material 10 is formed, for example, wider than the second stretchable conductor pattern 40, and the electrode connection portion 23 and the connection portion 63 are electrically connected to each other via the second stretchable conductor pattern 40. According to such a configuration, when the second stretchable base material 30 is laminated on the first stretchable base material 10, it becomes easy to align the second stretchable conductor pattern 40 so as to overlap (be connected to) the electrode connection portion 23 in a plan view. Therefore, it becomes easier to electrically connect the first stretchable conductor pattern 20 and the connection portion 63 to each other via the second stretchable conductor pattern 40.

[0025] More specifically, the electrode connection portion 23a locally projects from the electrode 22a, for example, toward one side in the radial direction of the electrode 22a (more specifically, toward the second stretchable conductor pattern 40 side in the radial direction of the electrode 22a). Similarly, the electrode connection portion 23b locally projects from the electrode 22b, for example, toward one side in the radial direction of the electrode 22b (more specifically, toward the second stretchable conductor pattern 40 side in the radial direction of the electrode 22b). The electrode connection portion 23c locally projects from the electrode 22c, for example, toward one side in the radial direction of the electrode 22c (more specifically, toward the second stretchable conductor pattern 40 side in the radial direction of the electrode 22c). Each of the plurality of electrode connection portions 23 (the electrode connection portion 23a to the electrode connection portion 23c) is set to have the same shape and the same dimensions as each other. More specifically, in the case of this embodiment, the planar shape of each of the plurality of electrode connection portions 23 is a substantially semi-circular shape convex toward the second stretchable conductor pattern 40 side. In a plan view, the aggregate of the electrode 22 and the electrode connection portion 23 has a shape in which a part of one perfect circle and a part of another perfect circle having a smaller diameter than the perfect circle overlap each other. As shown in FIG. 6, the width dimension W2 of each of the plurality of electrode connection portions 23 (the dimension in the direction orthogonal to the protruding direction of the electrode connection portion 23) is smaller than the outer diameter of each of the plurality of electrodes 22. Similarly, the length dimension of each of the plurality of electrode connection portions 23 (the dimension in the protruding direction of the electrode connection portion 23) is smaller than the outer diameter of each of the plurality of electrodes 22. According to such a configuration, for example, even when the plurality of electrodes 22 are arranged close to each other (see FIGS. 10(a) and 10(b)), the corresponding electrodes 22 and the external terminal portions 62 can be more reliably and more easily connected via the second stretchable conductor pattern 40. That is, the arrangement of the plurality of electrodes 22 can be designed with a higher degree of freedom. Note that the planar shape and positional relationship of each of the electrode 22 and the electrode connection portion 23 are not limited to the above-described example, and can be appropriately set according to the dimensions and uses of the stretchable wiring substrate 100. More specifically, for example, the planar shape of the electrode 22 is not limited to a perfect circular shape, and may be an oval shape or a rectangular shape. Similarly, the planar shape of the electrode connection portion 23 is not limited to a substantially semi-circular shape, and may be a rectangular shape or a linear shape. Furthermore, the planar shape of the aggregate of the electrode 22 and the electrode connection portion 23 may be formed into a perfect circular shape, an oval shape, a rectangular shape, a shape that gradually tapers toward the tip side (for example, a drop shape), or the like.

[0026] Also, in the case of the present embodiment, an opening 31 for exposing the electrode 22 is formed in the second stretchable base material 30. The electrode 22 is exposed from the second stretchable base material 30 through the opening 31 formed in the second stretchable base material 30. More specifically, in the case of the present embodiment, a plurality (more specifically, the same number as the electrodes 22) of openings 31 are formed in the second stretchable base material 30, and the plurality of openings 31 include an opening 31a, an opening 31b, and an opening 31c. Through the opening 31a, the electrode 22a is exposed from the second stretchable base material 30, through the opening 31b, the electrode 22b is exposed from the second stretchable base material 30, and through the opening 31, the electrode 22c is exposed from the second stretchable base material 30. The opening 31 is formed to have a smaller diameter than the electrode 22. In a plan view, the entirety of each opening 31 is within the outer contour line of the corresponding electrode 22. The openings 31a to 31c are set to have the same shape and the same dimensions as each other. The planar shape of the openings 31a to 31c is not particularly limited, but as an example, it is a circular shape. Also, the outer diameter of the opening 31 is smaller than the outer diameter of the electrode 22 (electrodes 22a to 22c).

[0027] As shown in FIG. 1, in a plan view, among the first stretchable conductor patterns 20, the outer peripheral edge portion of the electrode 22 and the entirety of the electrode connection portion 23 are covered by the second stretchable base material 30. On the other hand, the portion of the electrode 22 excluding the outer peripheral edge portion is exposed from the second stretchable base material 30 through the corresponding opening 31.

[0028] Similar to the first stretchable conductor pattern 20, the second stretchable conductor pattern 40 has conductivity and can transmit electrical signals and currents. Further, the second stretchable conductor pattern 40 can be deformed following the stretching and shrinking of the second stretchable substrate 30.

[0029] In the case of this embodiment, the end portion on the connection portion 63 side in the second stretchable conductor pattern 40 (in the case of this embodiment, the left end portion 43a of the bridge portion 42 described below) extends linearly. More specifically, in the case of this embodiment, the second stretchable conductor pattern 40 includes a plurality (for example, the same number as the plurality of electrodes 22) of bridge portions 42 (in the case of this embodiment, bridge portion 42a, bridge portion 42b, and bridge portion 42c). The bridge portion 42a electrically connects the corresponding connection portion 63 (in the case of this embodiment, the connection portion 63a described later) and the electrode connection portion 23a (and thus the electrode 22a) to each other. Similarly, the bridge portion 42b electrically connects the corresponding connection portion 63 (in the case of this embodiment, the connection portion 63b described later) and the electrode connection portion 23b (and thus the electrode 22b) to each other. The bridge portion 42c electrically connects the corresponding connection portion 63 (in the case of this embodiment, the connection portion 63c described later) and the electrode connection portion 23c (and thus the electrode 22c) to each other. Even more specifically, the left end portion 43a of each of the bridge portions 42a to 42c is directly connected to the corresponding connection portion 63, and the right end portion 43b of each of the bridge portions 42a to 42c is directly connected to the corresponding electrode connection portion 23. Each of the bridge portions 42 extends linearly in the longitudinal direction. More specifically, each of the left end portion 43a and the right end portion 43b of the bridge portion 42a extends linearly along the longitudinal direction, and the middle portion of the bridge portion 42a is linearly inclined obliquely upward to the right in FIG. 1. Similarly, each of the left end portion 43a and the right end portion 43b of the bridge portion 42c extends linearly along the longitudinal direction, and the middle portion (the middle in the extending direction) of the bridge portion 42c is linearly inclined obliquely downward to the right in FIG. 1. On the other hand, the entire bridge portion 42b extends linearly along the longitudinal direction. Each of the bridge portions 42 is arranged side by side at intervals from each other in the short side direction. The width dimension (the dimension in the direction orthogonal to the extending direction) of each of the bridge portions 42 is constant regardless of the position in the extending direction. Further, the right end portions 43b of the bridge portions 42a to 42c terminate on the connection portion 63 side (in the case of this embodiment, the left side) rather than the corresponding openings 31, and the right end portions 43b and the openings 31 are separated from each other in the longitudinal direction. And the separation distance L2 between the right end portion 43b and the electrode 22 in the longitudinal direction is smaller than the length dimension L1 of the electrode connection portion 23. According to such a configuration, the alignment of the opening 31 with respect to the electrode 22 and the alignment of the bridge portions 42a to 42c with respect to the electrode connection portion 23 are each made easier.

[0030] The reinforcing base material 50 has higher rigidity and is non-stretchable than each of the first stretchable base material 10 and the second stretchable base material 30. Here, the rigidity of the reinforcing base material 50 is the product (E·I) of the Young's modulus (E) and the second moment of area (I). And "having high rigidity" means at least either one of being difficult to deform with respect to the bending load in the direction intersecting the plane direction, that is, having high bending rigidity, or being difficult to deform with respect to the tensile stress in the in-plane direction, and it is preferable that both are meant.

[0031] As shown in FIG. 2, the reinforcing base material 50 is disposed, for example, between the left end portions of the first stretchable base material 10 and the second stretchable base material 30 in the layer. The lower surface of the reinforcing base material 50 is directly laminated on one main surface 10a of the first stretchable base material 10. Further, the upper surface of the reinforcing base material 50 is directly laminated on one main surface 30a of the second stretchable base material 30 except for the formation region of the second stretchable conductor pattern 40. Note that the present invention is not limited to this example, and the reinforcing base material 50 may be indirectly laminated on one main surface 10a of the first stretchable base material 10, or may be directly or indirectly laminated on the other main surface 10b of the first stretchable base material 10.

[0032] In the case of this embodiment, as shown in FIG. 1, the planar shape of the reinforcing base material 50 is formed, for example, in a substantially rectangular shape that is long in the longitudinal direction. However, in the present invention, the planar shape of the reinforcing base material 50 is not limited to this example, and may be a perfect circular shape or an oval shape, and further may include an annular frame portion (not shown) extending along the outer peripheral edges of the first stretchable base material 10 and the second stretchable base material 30. The reinforcing base material 50 is a flexible member and has a Young's modulus larger than that of the first stretchable base material 10. The material of the reinforcing base material 50 is not particularly limited, but a synthetic resin having low slidability, corrosion resistance, and high strength, such as polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polyimide (PI), polyphenylene sulfide (PPS), or fluororesin, can be used. In addition, a paper material having appropriate durability, such as cellulose nanofiber paper, may be used for the reinforcing base material 50.

[0033] The thickness dimension of the reinforcing base material 50 is not particularly limited, but is preferably 10 μm or more and 200 μm or less, and more preferably 50 μm or more and 100 μm or less.

[0034] As shown in FIGS. 2 and 3, the external side wiring pattern 60 includes a plurality (for example, the same number as the plurality of electrodes 22) of external terminal portions 62 and connection portions 63. And one connection portion 63 electrically connects one electrode 22 and one external terminal portion 62 to each other. The plurality of external terminal portions 62 include an external terminal portion 62a electrically connected to the electrode 22a, an external terminal portion 62b electrically connected to the electrode 22b, and an external terminal portion 62c electrically connected to the electrode 22c. Similarly, the plurality of connection portions 63 include a connection portion 63a connecting the external terminal portion 62a and the electrode 22a to each other, a connection portion 63b connecting the external terminal portion 62b and the electrode 22b to each other, and a connection portion 63c connecting the external terminal portion 62c and the electrode 22c to each other.

[0035] Here, in the case of the present embodiment, as described above, the end portion on the connection portion 63 side in the second stretchable conductor pattern 40 (in the case of the present embodiment, the left end portion 43a of the bridge portion 42) extends linearly. And the end portion on the second stretchable conductor pattern 40 side in the connection portion 63 (in the case of the present embodiment, the right end portion 64a of the linear portions 61a, 61b, 61c described below) extends linearly along the end portion on the connection portion 63 side in the second stretchable conductor pattern 40 (the same as above). That is, for example, compared with the case where the end portion on the second stretchable conductor pattern 40 side in the connection portion 63 and the end portion on the connection portion 63 side in the second stretchable conductor pattern 40 extend in directions intersecting each other, the alignment between the second stretchable conductor pattern 40 and the external terminal portion 62 is performed under more severe conditions. Even with such a configuration, as described above, the end portion on the electrode 22 side in the second stretchable conductor pattern 40 (in the case of this embodiment, the right end portion 43b of the bridge portion 42) is connected to the electrode connection portion 23 formed wider than the second stretchable conductor pattern 40. Therefore, it is easy to align the electrode connection portion 23 and the end portion on the electrode 22 side in the second stretchable conductor pattern 40. For this reason, when connecting the first stretchable conductor pattern 20 and the connection portion 63 to each other via the second stretchable conductor pattern 40, it is sufficient to mainly align the end portion on the connection portion 63 side in the second stretchable conductor pattern 40 and the end portion on the second stretchable conductor pattern 40 side in the connection portion 63. Therefore, in the width direction of each of the second stretchable conductor pattern 40 and the connection portion 63, it is easy to align the second stretchable conductor pattern 40 so as to overlap (be connected to) the connection portion 63 in a plan view. More specifically, the end portion on the second stretchable conductor pattern 40 side in the connection portion 63 and the end portion on the connection portion 63 side in the second stretchable conductor pattern 40 extend linearly, for example, in the same direction (for example, the longitudinal direction of the first stretchable base material 10). When laminating the second stretchable base material 30 on the first stretchable base material 10, alignment is performed so that the second stretchable conductor pattern 40 overlaps (is connected to) the connection portion 63 in both the extending direction and the width direction. However, in the present invention, the end portion on the second stretchable conductor pattern 40 side in the connection portion 63 and the end portion on the connection portion 63 side in the second stretchable conductor pattern 40 may extend in different directions from each other (the extending directions may intersect each other).

[0036] Also, in the case of this embodiment, the amount of misalignment in the width direction between the width center of the end portion on the connection portion 63 side in the second stretchable conductor pattern 40 (the same as above) and the width center of the end portion on the second stretchable conductor pattern 40 side in the connection portion 63 (the same as above) may be smaller than the amount of misalignment in the width direction between the width center of the end portion on the electrode connection portion 23 side in the second stretchable conductor pattern 40 (in the case of this embodiment, the right end portion 43b of the bridge portion 42) and the width center of the electrode connection portion 23. In other words, when laminating the second stretchable base material 30 onto the first stretchable base material 10, the allowable range of the displacement amount in the width direction between the width center of the end portion (the same as above) on the connection portion 63 side in the second stretchable conductor pattern 40 and the width center of the end portion (the same as above) on the second stretchable conductor pattern 40 side in the connection portion 63 is smaller than the allowable range of the displacement amount in the width direction between the width center of the end portion (the same as above) on the electrode connection portion 23 side in the second stretchable conductor pattern 40 and the width center of the electrode connection portion 23. Therefore, when laminating the second stretchable base material 30 onto the first stretchable base material 10, it is only necessary to mainly consider the displacement in the width direction between the second stretchable conductor pattern 40 and the connection portion 63. Thus, the second stretchable conductor pattern 40 can be easily aligned with the corresponding connection portion 63 and electrode connection portion 23. In the present invention, among the plurality of bridge portions 42, the displacement amount of the bridge portion 42 having the largest displacement amount with respect to the connection portion 63 may be smaller than the displacement amount of the bridge portion 42 having the largest displacement amount with respect to the electrode connection portion 23. That is, among the plurality of bridge portions 42, the bridge portion 42 having the largest displacement amount with respect to the connection portion 63 and the bridge portion 42 having the largest displacement amount with respect to the electrode connection portion 23 may be different bridge portions 42 from each other. In the present invention, the displacement amount in the width direction between the width center of the end portion on the connection portion 63 side in the second stretchable conductor pattern 40 and the width center of the end portion on the second stretchable conductor pattern 40 side in the connection portion 63 may be equal to the displacement amount in the width direction between the width center of the end portion on the electrode connection portion 23 side in the second stretchable conductor pattern 40 and the width center of the electrode connection portion 23.

[0037] In the present invention, it is preferable that the width center of the end portion on the connection portion 63 side in the second stretchable conductor pattern 40 and the width center of the end portion on the second stretchable conductor pattern 40 side in the connection portion 63 substantially coincide with each other in the width direction. By doing so, the end portion on the second stretchable conductor pattern 40 side in the connection portion 63 can be arranged to overlap on the same straight line as the end portion on the connection portion 63 side in the second stretchable conductor pattern 40. On the other hand, the width center of the end on the electrode connection portion 23 side in the second stretchable conductor pattern 40 and the width center of the electrode connection portion 23 do not necessarily coincide with each other in the width direction. Even in such a case, since the electrode connection portion 23 is formed wider than the second stretchable conductor pattern 40 as described above, in a plan view, it is easy to align the entire width direction of the end on the electrode 22 side in the second stretchable conductor pattern 40 so that it falls within the width range of the electrode connection portion 23. However, in the present invention, at least a part of the end on the connection portion 63 side in the second stretchable conductor pattern 40 and the end on the second stretchable conductor pattern 40 side in the connection portion 63 only need to be connected to each other, and they do not necessarily need to be arranged overlapping on the same straight line. Similarly, at least a part of the end on the electrode connection portion 23 side in the second stretchable conductor pattern 40 and the electrode connection portion 23 only need to be connected to each other. For example, in a plan view, a part of the end on the electrode 22 side in the second stretchable conductor pattern 40 may protrude from the electrode connection portion 23 in the width direction.

[0038] More specifically, the external side wiring pattern 60 includes a plurality of straight portions 61a, 61b, 61c that extend linearly in the longitudinal direction. Among these, the portion on the second stretchable conductor pattern 40 side in the straight portion 61a constitutes the connection portion 63a, and the portion on the side opposite to the second stretchable conductor pattern 40 side constitutes the external terminal portion 62a. Similarly, the portion on the second stretchable conductor pattern 40 side in the straight portion 61b constitutes the connection portion 63b, and the portion on the side opposite to the second stretchable conductor pattern 40 side constitutes the external terminal portion 62b. The portion on the second stretchable conductor pattern 40 side in the straight portion 61c constitutes the connection portion 63c, and the portion on the side opposite to the second stretchable conductor pattern 40 side constitutes the external terminal portion 62c. Each of the plurality of straight portions 61a to 61c is arranged spaced apart from each other in the short width direction. The width dimension of each of the plurality of external terminal portions 62 is substantially constant regardless of the position in the extending direction of the external terminal portion 62. Similarly, the width dimension of each of the plurality of connection portions 63 is substantially constant regardless of the position in the extending direction of the connection portion 63. Also, the width dimension of each of the plurality of connection portions 63 is set to be smaller than the width dimension of each of the corresponding bridge portions 42. Thereby, in a plan view, it becomes easy to align the entirety of the connection portion 63 so as to be within the width range of the corresponding bridge portion 42. Also, the width dimension of each of the plurality of connection portions 63 is set to be smaller than the width dimension of each of the plurality of external terminal portions 62. Note that the planar shape and positional relationship of the external side wiring pattern 60 are not limited to the above example, and can be appropriately set according to the dimensions and uses of the stretchable wiring board 100.

[0039] The width dimension W1 of each of the bridge portions 42 is preferably, for example, 0.1 mm or more and 2.0 mm or less, and more preferably 0.2 mm or more and 1.0 mm or less. The width dimension of each of the plurality of external terminal portions 62 is preferably, for example, 0.1 mm or more and 2.0 mm or less, and more preferably 0.2 mm or more and 1.0 mm or less. The width dimension of each of the plurality of connection portions 63 is preferably, for example, 0.05 mm or more and 1.0 mm or less, and more preferably 0.15 mm or more and 0.35 mm or less. The width dimension W2 of the electrode connection portion 23 is preferably, for example, 1.5 times or more and 5 times or less the width dimension W1 of each of the bridge portions 42, and more preferably 2 times or more and 4 times or less the width dimension W1.

[0040] Furthermore, the stretchable wiring board 100 includes a reinforcing plate 55 laminated on the other main surface 50b (the surface opposite to the one main surface 50a) of the reinforcing base material 50. The reinforcing plate 55 is a spacer member for adjusting the thickness of the left end portion of the reinforcing base material 50 to the accuracy specified by the connector or the like (not shown) of the external device when fitting and connecting the external terminal portion 62 to the connector or the like of the external device. The reinforcing plate 55 is joined, for example, to the upper surface of the left end portion of the reinforcing base material 50 via an adhesive (not shown).

[0041] In the case of this embodiment, each of the first stretchable conductor pattern 20, the second stretchable conductor pattern 40, and the external side wiring pattern 60 is, for example, a coating film composed of a conductive filler and a binder containing a thermoplastic resin. Therefore, when manufacturing the stretchable wiring board 100, by heating and pressurizing each of the first stretchable conductor pattern 20, the second stretchable conductor pattern 40, and the external side wiring pattern 60, the first stretchable conductor pattern 20 and the external side wiring pattern 60 can be mutually fused via the second stretchable conductor pattern 40. That is, without using a conductive adhesive or the like, the first stretchable conductor pattern 20 and the external side wiring pattern 60 can be electrically and mechanically connected to each other via the second stretchable conductor pattern 40 with a simpler structure, so that the manufacturability of the stretchable wiring board 100 can be improved. The conductive filler is composed of, for example, silver, gold, platinum, carbon, copper, aluminum, cobalt or nickel, or an alloy thereof, etc. Examples of the thermoplastic resin include thermoplastic elastomer materials such as urethane resin, acrylic resin, and silicone rubber. Also, as the thermoplastic resin, it is desirable to select one with a low Young's modulus so that the elastic modulus of the first stretchable conductor pattern 20 in the coated state is equal to or smaller than the elastic modulus of the first stretchable base material 10. The elastomer material may be used alone, or a plurality of types of elastomer materials may be mixed and used. Also, the forming method of each of the first stretchable conductor pattern 20, the second stretchable conductor pattern 40, and the external side wiring pattern 60 is not particularly limited, but can be formed, for example, by a printing method. The printing method is not particularly limited, but is, for example, a screen printing method, an inkjet printing method, a gravure printing method, an offset printing method, etc.

[0042] Here, in the case of this embodiment, the material of the first stretchable conductor pattern 20 is different from the material of the external side wiring pattern 60. More specifically, as an example, the conductive filler contained in the first stretchable conductor pattern 20 (and the second stretchable conductor pattern 40) is silver, and the conductive filler contained in the external side wiring pattern 60 is carbon. According to this embodiment, the first stretchable conductor pattern 20 and the external side wiring pattern 60 are respectively formed on different members (the first stretchable base material 10 and the reinforcing base material 50) in advance, and the pre-formed first stretchable conductor pattern 20 and the external side wiring pattern 60 are connected to each other via the second stretchable conductor pattern 40. Therefore, compared with the case where the first stretchable conductor pattern 20 and the external side wiring pattern 60 are directly printed and formed so as to be connected to each other, the first stretchable conductor pattern 20 and the external side wiring pattern 60 can be connected (fused) to each other well.

[0043] The thickness of the first stretchable conductor pattern 20 is not particularly limited, but is preferably 10 μm or more, and more preferably about 20 μm. Similarly, the thickness of the second stretchable conductor pattern 40 is not particularly limited, but is preferably 10 μm or more, and more preferably about 20 μm. Also, the thickness of the external side wiring pattern 60 is not particularly limited, but is preferably 10 μm or more, and more preferably about 20 μm.

[0044] As shown in FIGS. 2 and 3, the adhesive layer 81 is directly laminated on the other main surface 30b of the second stretchable base material 30. Note that the adhesive layer 81 may be indirectly laminated on the surface opposite to the other main surface 30b of the second stretchable base material 30. In plan view, the adhesive layer 81 is formed, for example, in substantially the same shape as the second stretchable base material 30. In plan view, the adhesive layer 81 covers, for example, the entire second stretchable base material 30. However, the adhesive layer 81 may locally cover a part of the second stretchable base material 30. Further, similar to the second stretchable base material 30, the adhesive layer 81 has a plurality of openings (a first opening (not shown), a second opening 81b, and a third opening (not shown)) that expose the electrode 22. The electrode 22a is exposed from the adhesive layer 81 through the first opening. Similarly, the electrode 22b is exposed from the adhesive layer 81 through the second opening 81b, and the electrode 22c is exposed from the adhesive layer 81 through the third opening. Note that the outer diameter of each opening (the first opening to the third opening) of the adhesive layer 81 is set to a dimension slightly larger than the outer diameter of the opening 31, for example. In the case of this embodiment, the adhesive layer 81 is formed by applying an adhesive material. More specifically, the adhesive layer 81 is a single film formed, for example, by applying an adhesive material with a desired thickness onto the upper surface of the first release film 71 and then curing it by a heat treatment process. Therefore, compared with the case where the adhesive layer 81 includes a core material such as a nonwoven fabric or paper, the adhesive layer 81 can follow the stretching of the first stretchable base material 10 better. The adhesive material is not particularly limited, and for example, an acrylic resin or the like can be used. In the case of attaching the stretchable wiring board 100 to the skin as in this embodiment, it is preferably a material having biocompatibility.

[0045] Here, in the case of this embodiment, the electrode 22 is covered with a peelable protective film. Before using the stretchable wiring board 100, the electrode 22 is covered with a peelable protective film, and when using the stretchable wiring board 100, the protective film is peeled off from the electrode 22. More specifically, in the case of this embodiment, as described above, the second release film 76 is directly laminated under the first stretchable base material 10, and the second release film 76 is the protective film. As shown in FIGS. 2 and 3, the lower surface of each of the plurality of electrodes 22 is covered by the second release film 76 through the first stretchable base material 10. Also, in a plan view, each of the plurality of electrodes 22 is within the outer contour line of the second release film 76.

[0046] The first release film 71 is laminated on the upper surface side of the adhesive layer 81 so as to be easily releasable from the adhesive layer 81. Similarly, the second release film 76 is laminated on the lower surface side of the first stretchable base material 10 so as to be easily releasable from the first stretchable base material 10. In FIG. 1, the adhesive layer 81, the first release film 71, and the second release film 76 are not shown. The outer shape of each of the first release film 71 and the adhesive layer 81 is formed, for example, in substantially the same shape and substantially the same dimensions as the outer shape of the second stretchable base material 30. Similarly, the outer shape of the second release film 76 is formed, for example, in substantially the same shape and substantially the same dimensions as the outer shape of the first stretchable base material 10. Further, the first release film 71 has a plurality of openings 71a, 71b, and 71c for exposing the electrodes 22, similar to the second stretchable base material 30. The electrode 22a is exposed from the adhesive layer 81 through the opening 71a. Similarly, the electrode 22b is exposed from the adhesive layer 81 through the opening 71b, and the electrode 22c is exposed from the adhesive layer 81 through the opening 71c. The outer diameter of each opening (opening 71a to opening 71c) of the adhesive layer 81 is set to a dimension slightly larger than the outer diameter of the opening 31.

[0047] The material of each of the first release film 71 and the second release film 76 is not particularly limited, and examples thereof include PET (polyethylene terephthalate) or paper. The first release film 71 and the second release film 76 may be made of the same material as each other, or may be made of different materials from each other.

[0048] The stretchable wiring board 100 further includes, for example, a conductive adhesive layer (not shown) that directly covers the electrode 22. Then, the electrode 22 can be favorably arranged along the skin of the living body by the conductive adhesive layer. More specifically, the stretchable wiring board 100 includes, for example, the same number of conductive adhesive layers as the plurality of electrodes 22, and each conductive adhesive layer directly covers the upper surface of the corresponding electrode 22. The material of the conductive adhesive layer is not particularly limited, and examples thereof include hydrogels and adhesives having conductivity.

[0049] When joining the first stretchable substrate 10, the second stretchable substrate 30, and the reinforcing substrate 50 to each other, for example, first, the first stretchable substrate 10 having the first stretchable conductor pattern 20 printed and formed on one main surface 10a is prepared respectively. Similarly, the second stretchable substrate 30 having the second stretchable conductor pattern 40 printed and formed on one main surface 30a and the reinforcing substrate 50 having the external terminal portion 62 printed and formed on one main surface 50a are prepared. Here, on the other main surface 30b of the second stretchable substrate 30, which is the surface opposite to the side where the second stretchable conductor pattern 40 is formed, a release film (not shown) is laminated, similar to the first stretchable substrate 10. The release film of the second stretchable substrate 30 is peeled off from the second stretchable substrate 30 after the second stretchable substrate 30 is laminated on the first stretchable substrate 10 and the reinforcing substrate 50. Next, in both the short side direction and the long side direction, the first stretchable substrate 10 and the reinforcing substrate 50 are aligned with each other and overlapped. More specifically, the first stretchable substrate 10 and the reinforcing substrate 50 are laminated with each other such that one main surface 10a of the first stretchable substrate 10 and one main surface 50a of the reinforcing substrate 50 are located on the same side. Subsequently, in both the short-side direction and the long-side direction, the second stretchable base material 30 is aligned with and superposed on each of the first stretchable base material 10 and the reinforcing base material 50. More specifically, one main surface 10a of the first stretchable base material 10, one main surface 50a of the reinforcing base material 50, and one main surface 30a of the second stretchable base material 30 are opposed to each other, and the first stretchable base material 10, the reinforcing base material 50, and the second stretchable base material 30 are laminated on each other, and the second stretchable conductor pattern 40 is disposed across the first stretchable conductor pattern 20 and the external side wiring pattern 60. At this time, in plan view, each opening 31 is accommodated inside the outer contour line of the corresponding electrode 22, and the end portion (right end portion 43b) on the electrode 22 side in the second stretchable conductor pattern 40 and the electrode connection portion 23 of the corresponding electrode 22 overlap each other, and the second stretchable base material 30 is aligned with the first stretchable base material 10. Similarly, in plan view, the end portion (left end portion 43a) on the connection portion 63 side in the second stretchable conductor pattern 40 and the end portion (right end portion 64a) on the second stretchable conductor pattern 40 side in the connection portion 63 overlap each other, and the second stretchable base material 30 is aligned with the reinforcing base material 50. Subsequently, the first stretchable base material 10, the second stretchable base material 30, and the reinforcing base material 50 are heated and pressurized. Thereby, the first stretchable base material 10, the second stretchable base material 30, and the reinforcing base material 50 can be fused to each other. The heating means is not particularly limited, but a lamination method using a heating roll or a heating press means can be adopted.

[0050] When using the stretchable wiring board 100, for example, first, a conductive adhesive layer is attached to each electrode 22 (electrodes 22a to 22c). Subsequently, the first release film 71 is peeled off from the adhesive layer 81 so that the adhesive layer 81 is exposed on the lower surface side of the stretchable wiring board 100. Then, the stretchable wiring board 100 can be attached to the skin through the adhesive layer 81 and the conductive adhesive layer. Therefore, the stretchable wiring board 100 is attached to the skin with one main surface 10a of the first stretchable base material 10 facing upward and the opposite surface (the other main surface 10b) facing downward. Next, the second release film 76 is peeled off from the first stretchable base material 10 so that the first stretchable base material 10 is exposed on the upper surface side of the stretchable wiring board 100.

[0051] <Modification Example> Next, a modification example of the embodiment will be described with reference to FIGS. 7 to 9. In FIG. 7, illustration of the adhesive layer 81, the first release film 71, and the second release film 76 is omitted. The stretchable wiring board 100 according to this modification example is different from the stretchable wiring board 100 according to the above-described embodiment in the points described below, and is configured in the same manner as the stretchable wiring board 100 according to the above-described embodiment in other points.

[0052] In the case of this modification example, as shown in FIG. 7, the first stretchable conductor pattern 20 does not include a plurality of electrode connection portions 23, and instead includes a plurality (for example, the same number as the plurality of electrodes 22) of wiring portions 26. And the electrode 22 is electrically connected to the second stretchable conductor pattern 40 and thus to the connection portion 63 via the corresponding wiring portion 26. More specifically, the plurality (for example, three) of wiring portions 26 include, for example, a wiring portion 26a extending linearly from the electrode 22a, a wiring portion 26b extending linearly from the electrode 22b, and a wiring portion 26c extending linearly from the electrode 22c. In the case of this modification example, the planar shape of the wiring portion 26a is substantially the same as the planar shape of the bridge portion 42a in the above-described embodiment. Similarly, the planar shape of the wiring portion 26b is substantially the same as the planar shape of the bridge portion 42b in the above-described embodiment, and the planar shape of the wiring portion 26c is substantially the same as the planar shape of the bridge portion 42c in the above-described embodiment. Note that the planar shape and positional relationship of each of the wiring portions 26 are not limited to the above example, and can be appropriately set according to the dimensions and uses of the stretchable wiring board 100.

[0053] Also, in the case of this modified example, the outer dimensions of the second stretchable base material 30 are smaller than those of the first stretchable base material 10. More specifically, the length dimension of the second stretchable base material 30 is smaller than the length dimension of the first stretchable base material 10. Similarly, the width dimension of the second stretchable base material 30 is smaller than the width dimension of the first stretchable base material 10. And the second stretchable base material 30 is locally laminated on the end portion (left end portion in the case of this modified example) on the external terminal portion 62 side of the first stretchable base material 10. The left end of the first stretchable base material 10 and the left end of the second stretchable base material 30 are arranged at positions offset to the left (toward the reinforcing base material 50 side) from the left end of the first stretchable base material 10. Also, in the case of this modified example, the plurality of bridge portions 42 (bridge portions 42a to 42c) included in the second stretchable conductor pattern 40 extend linearly along the first direction. The width dimension of each bridge portion 42 is substantially constant regardless of the position in the extending direction. Each bridge portion 42 electrically connects the corresponding connection portion 63 and the wiring portion 26 (and thus the electrode 22) to each other. The length dimension of each of the plurality of bridge portions 42 included in the second stretchable conductor pattern 40 is smaller than the length dimension of each of the plurality of wiring portions 26 of the first stretchable conductor pattern 20. And each of the bridge portions 42 is directly connected to the end portion (left end portion in the case of this modified example) on the external terminal portion 62 side of the corresponding wiring portion 26. Thereby, the corresponding electrodes 22 and the external terminal portions 62 are electrically connected to each other via the second stretchable conductor pattern 40. As shown in FIG. 7, each of the bridge portions 42a to 42c is arranged on the same straight line as the left end portions of the corresponding wiring portions 26a to 26c and each of the connection portions 63a to 63c. According to such a configuration, it is possible to make the stretchability (easiness of stretching) of the stretchable wiring board 100 switch stepwise from the reinforcing base material 50 toward the first stretchable base material 10. Therefore, it is possible to suppress stress from concentrating on the portion of the second stretchable conductor pattern 40 straddling the reinforcing base material 50 and the first stretchable base material 10.

[0054] In this modified example as well, it is preferable that the width center of the end portion on the connection portion 63 side (more specifically, the left end portion of the bridge portion 42) of the second stretchable conductor pattern 40 and the width center of the end portion on the second stretchable conductor pattern 40 side of the connection portion 63 substantially coincide with each other at least in the width direction. By doing so, the end portion on the second stretchable conductor pattern 40 side of the connection portion 63 can be arranged to overlap with the end portion on the connection portion 63 side of the second stretchable conductor pattern 40 on the same straight line. Similarly, it is preferable that the width center of the end portion on the wiring portion 26 side (more specifically, the right end portion of the bridge portion 42) of the second stretchable conductor pattern 40 and the width center of the end portion on the second stretchable conductor pattern 40 side of the wiring portion 26 (in the case of this modified example, the left end portion) substantially coincide with each other at least in the width direction. By doing so, the end portion on the wiring portion 26 side of the second stretchable conductor pattern 40 can be arranged to overlap with the end portion on the second stretchable conductor pattern 40 side of the wiring portion 26 on the same straight line.

[0055] However, in the present invention, as described above, it is sufficient that at least a part of the end portion on the connection portion 63 side of the second stretchable conductor pattern 40 and the end portion on the second stretchable conductor pattern 40 side of the connection portion 63 are connected to each other, and they do not necessarily have to overlap and be arranged on the same straight line. Similarly, in the present invention, it is sufficient that at least a part of the end portion on the wiring portion 26 side of the second stretchable conductor pattern 40 and the end portion on the second stretchable conductor pattern 40 side of the wiring portion 26 are connected to each other, and they do not necessarily have to overlap and be arranged on the same straight line.

[0056] Also, in the case of this modified example, the width dimension of the connection portion 63 is smaller than the width dimension of the second stretchable conductor pattern 40 (more specifically, each corresponding bridge portion 42), for example. Therefore, in a plan view, it becomes easy to align so that the entire width direction of the end portion on the second stretchable conductor pattern 40 side of the connection portion 63 is within the width range of the end portion on the wiring portion 26 side of the second stretchable conductor pattern 40. Similarly, in the case of this modified example, the end portion of the wiring portion 26 on the side of the second stretchable conductor pattern 40 is, for example, locally narrower than other portions. More specifically, the width dimension of the end portion (left end portion) of the wiring portion 26 on the side of the second stretchable conductor pattern 40 is smaller than the width dimension of the second stretchable conductor pattern 40 (more specifically, each corresponding bridge portion 42), for example. For this reason, in a plan view, it becomes easy to align the entire width direction of the end portion of the wiring portion 26 on the side of the second stretchable conductor pattern 40 so as to be within the width range of the end portion of the second stretchable conductor pattern 40 on the wiring portion 26 side.

[0057] Also, in the case of this modified example, as shown in FIGS. 8 and 9, the stretchable wiring substrate 100 further includes a stretchable cover 90 that is laminated on one main surface 10a of the first stretchable base material 10 and covers the first stretchable conductor pattern 20. And the electrode 22 is exposed from the stretchable cover 90 through the opening 91 formed in the stretchable cover 90. More specifically, for example, a plurality (for example, the same number as the plurality of electrodes 22) of openings 91 are formed in the stretchable cover 90, and each electrode 22 is exposed from the stretchable cover 90 through the corresponding opening 91. The planar shape of the stretchable cover 90 is formed, for example, in a substantially rectangular shape that is longer than the first stretchable base material 10. The stretchable cover 90 covers the entire first stretchable base material 10 in a plan view.

[0058] The material constituting the stretchable cover 90 is not particularly limited, but is, for example, an elastomer material similar to the first stretchable base material 10. However, the stretchable cover 90 only needs to be constituted of a material having at least insulation and stretchability, and may be constituted of a material different from the first stretchable base material 10. The thickness dimension of the stretchable cover 90 is preferably, for example, 50 μm or less, and more preferably 5 μm or less.

[0059] Even with such a configuration, since the second stretchable conductor pattern connecting the first stretchable conductor pattern 20 and the connection portion 63 is well supported by the second stretchable base material 30, the structural strength of the second stretchable conductor pattern 40 can be sufficiently ensured. Therefore, it is possible to more easily realize the stretchable wiring board 100 having a structure in which the first stretchable conductor pattern 20 and the external terminal portion 62 are exposed on the same surface of the stretchable wiring board 100 and having excellent connection reliability.

[0060] When joining the first stretchable base material 10, the second stretchable base material 30, and the reinforcing base material 50 to each other, first, the first stretchable base material 10 having the first stretchable conductor pattern 20 printed and formed on one main surface 10a is prepared in the same manner as in the embodiment. Similarly, the second stretchable base material 30 having the second stretchable conductor pattern 40 printed and formed on one main surface 30a and the reinforcing base material 50 having the external terminal portion 62 printed and formed on one main surface 50a are prepared. Next, in both the short side direction and the long side direction, the first stretchable base material 10 and the reinforcing base material 50 are aligned with each other and overlapped. At this time, in a plan view, the first stretchable base material 10 and the reinforcing base material 50 are aligned with each other so that the end portion (left end portion 43a) on the connection portion 63 side of the second stretchable conductor pattern 40 and the end portion (right end portion 64a) on the second stretchable conductor pattern 40 side of the connection portion 63 are arranged on the same straight line. Subsequently, in both the short side direction and the long side direction, the second stretchable base material 30 is aligned with and overlapped with each of the first stretchable base material 10 and the reinforcing base material 50. At this time, in a plan view, the second stretchable base material 30 is aligned with the first stretchable base material 10 so that each opening 31 is within the outer contour line of the corresponding electrode 22 and the end portion (right end portion 43b) on the electrode 22 side of the second stretchable conductor pattern 40 overlaps with the corresponding wiring portion 26. Similarly, in a plan view, the second stretchable base material 30 is aligned with the reinforcing base material 50 so that the end portion (left end portion 43a) on the connection portion 63 side of the second stretchable conductor pattern 40 and the end portion (right end portion 64a) on the second stretchable conductor pattern 40 side of the connection portion 63 overlap with each other. Subsequently, the first stretchable base material 10, the second stretchable base material 30, and the reinforcing base material 50 are heated and pressed. As a result, the first stretchable base material 10, the second stretchable base material 30, and the reinforcing base material 50 can be fused to each other.

[0061] As described above, the embodiments and modifications have been described with reference to the drawings. However, these are merely examples of the present invention, and various configurations other than those described above can also be adopted.

[0062] For example, in the above-described embodiment, an example in which a biological signal such as an electroencephalogram, an electromyogram, and an electrocardiogram is detected from a living body by the first stretchable conductor pattern 20 has been described. However, in the present invention, the first stretchable conductor pattern 20 may be configured such that, for example, a part thereof functions as an antenna and the signal received by the antenna is transmitted to an external device (not shown).

[0063] Further, in the present invention, the number of electrodes 22, the number of external terminal portions 62, and the number of connection portions 63 provided in the stretchable wiring board 100 are not limited to the above-described examples, and can be appropriately set according to the shape and use of the stretchable wiring board 100.

[0064] This embodiment includes the following technical ideas. (1) A first stretchable base material having a first stretchable conductor pattern including an electrode formed on one main surface, A reinforcing base material having an external side wiring pattern including an external terminal portion and a connection portion formed on one main surface, A second stretchable base material having a second stretchable conductor pattern formed on one main surface, A stretchable wiring board including: The second stretchable base material is laminated on the first stretchable base material and the reinforcing base material, and the first stretchable conductor pattern and the connection portion are electrically connected to each other via the second stretchable conductor pattern. A stretchable wiring board in which the electrode and the external terminal portion are exposed on the same surface of the stretchable wiring board. (2) The stretchable wiring board according to (1), wherein an opening for exposing the electrode is formed in the second stretchable base material. (3) The first stretchable conductor pattern includes the electrode and an electrode connection portion that is connected to the electrode and covered by the second stretchable base material. The electrode connection portion is formed wider than the second stretchable conductor pattern. The stretchable wiring board according to (2), wherein the electrode connection portion and the connection portion are electrically connected to each other via the second stretchable conductor pattern. (4) The end portion on the connection portion side in the second stretchable conductor pattern extends linearly. The stretchable wiring board according to any one of (1) to (3), wherein the end portion on the second stretchable conductor pattern side in the connection portion extends linearly along the end portion on the connection portion side in the second stretchable conductor pattern. (5) The amount of displacement in the width direction between the width center of the end portion on the connection portion side in the second stretchable conductor pattern and the width center of the end portion on the second stretchable conductor pattern side in the connection portion is smaller than the amount of displacement in the width direction between the width center of the end portion on the electrode connection portion side in the second stretchable conductor pattern and the width center of the electrode connection portion. The stretchable wiring board according to (4). (6) The stretchable wiring board according to any one of (1) to (5), wherein the material of the first stretchable conductor pattern is different from the material of the external side wiring pattern. (7) The stretchable wiring board according to any one of (1) to (6), wherein the electrode is covered with a peelable protective film.

Description of Reference Numerals

[0065] 10 First stretchable base material 10a One main surface 10b The other main surface 20 First stretchable conductor pattern 22, 22a, 22b, 22c Electrodes 23, 23a, 23b, 23c Electrode connection portions 26, 26a, 26b, 26c Wiring portions 30 Second stretchable base material 30a One main surface 30b The other main surface 31, 31a, 31b, 31c openings 40 Second stretchable conductor pattern 42, 42a, 42b, 42c Bridge portions 43a Left end (end on the connection side) 43b Right end (end on the electrode connection side) 50 Reinforcing substrate 50a One main surface 50b The other main surface 55 Reinforcing plate 60 External side wiring pattern 61a, 61b, 61c Straight portions 62, 62a, 62b, 62c External terminal portions 63, 63a, 63b, 63c Connection portions 64a Right end (end on the second stretchable conductor pattern side) 71 First release film 71a, 71b, 71c Openings 76 Second release film (protective film) 81 Adhesive layer 81b Opening 90 Stretchable cover 91 Opening 100 Stretchable wiring board 401 Virtual line

Claims

1. A first stretchable base material having a first stretchable conductor pattern including an electrode formed on one main surface, A reinforcing base material having an external side wiring pattern including an external terminal portion and a connection portion formed on one main surface, A second stretchable base material having a second stretchable conductor pattern formed on one main surface, A stretchable wiring board comprising: The second stretchable base material is laminated on the first stretchable base material and the reinforcing base material, and the first stretchable conductor pattern and the connection portion are electrically connected to each other via the second stretchable conductor pattern, A stretchable wiring board in which the electrode and the external terminal portion are exposed on the same surface of the stretchable wiring board.

2. The stretchable wiring board according to claim 1, wherein an opening for exposing the electrode is formed in the second stretchable base material.

3. The first stretchable conductor pattern includes the electrode and an electrode connection portion that is connected to the electrode and covered by the second stretchable base material, The electrode connection portion is formed wider than the second stretchable conductor pattern, The stretchable wiring board according to claim 2, wherein the electrode connection portion and the connection portion are electrically connected to each other via the second stretchable conductor pattern.

4. An end portion on the connection portion side in the second stretchable conductor pattern extends linearly, The stretchable wiring board according to claim 3, wherein an end portion on the second stretchable conductor pattern side in the connection portion extends linearly along the end portion on the connection portion side in the second stretchable conductor pattern.

5. The amount of displacement in the width direction between the width center of the end portion on the connection portion side in the second stretchable conductor pattern and the width center of the end portion on the second stretchable conductor pattern side in the connection portion is smaller than the amount of displacement in the width direction between the width center of the end portion on the electrode connection portion side in the second stretchable conductor pattern and the width center of the electrode connection portion. The stretchable wiring board according to claim 4.

6. The stretchable wiring board according to any one of claims 1 to 5, wherein the material of the first stretchable conductor pattern and the material of the external side wiring pattern are different from each other.

7. The stretchable wiring board according to any one of claims 1 to 5, wherein the electrode is covered with a peelable protective film.

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