Component mounting board

Abstract

To provide a component mounting board having a configuration capable of more surely detecting an immersion of the component mounting board in a liquid.SOLUTION: A component mounting board 100 includes: a board 10 having a base material 11, a first conductive pattern 30 formed on the base material 11 and a mounting component 50 electrically connected to the first conductive pattern 30; and a second conductive pattern 40 composing a circuit 60 complementary with the first conductive pattern 30. A portion corresponding to the second conductive pattern 40 in the base material 11 is a missing portion 12 which is missing, and the second conductive pattern 40 is soluble to a liquid or weakens when getting wet by a liquid.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a component mounting substrate.

Background Art

[0002] Patent Document 1 describes a component mounting substrate (sensor in the same document) including a substrate and a tuned radio frequency circuit supported by the substrate. The tuned radio frequency circuit has a first conductive pattern, a first capacitor, and a jumper, all disposed on the same side of the substrate. The first capacitor includes a first capacitor plate, a second capacitor plate, and a first dielectric material disposed between the first capacitor plate and the second capacitor plate, and the first dielectric material is soluble in a liquid.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] According to the study of the inventor of the present application, there is room for improvement in the component mounting substrate of Patent Document 1 from the viewpoint of more surely detecting that the component mounting substrate is immersed in a liquid.

[0005] The present invention has been made in view of the above problems, and provides a component mounting substrate having a structure capable of more surely detecting that the component mounting substrate is immersed in a liquid.

Means for Solving the Problems

[0006] According to the present invention, a substrate having a base material, a first conductive pattern formed on the base material, and a mounting component electrically connected to the first conductive pattern, a second conductive pattern that forms a circuit complementarily with the first conductive pattern, Equipped with, In the substrate, the portion corresponding to the second conductive pattern is a missing portion. The second conductive pattern provides a component mounting substrate that is soluble in liquid or becomes brittle when wetted by liquid. [Effects of the Invention]

[0007] According to the present invention, it is possible to more reliably detect when a component mounting substrate is immersed in a liquid. [Brief explanation of the drawing]

[0008] [Figure 1] This is an end view of a component mounting board according to the first embodiment. [Figure 2] This is an exploded end view of a component mounting board according to the first embodiment. [Figure 3] This is a plan view of a component mounting board according to the first embodiment. [Figure 4] This is a plan view of a component mounting board according to the first embodiment, selectively illustrating the board. [Figure 5] This is a plan view of the second substrate of the component mounting substrate according to the first embodiment. [Figure 6] Figures 6(a), 6(b), and 6(c) illustrate a method for manufacturing a component mounting substrate according to the first embodiment, and in particular show examples of processes performed on the substrate before it is combined with the second substrate. [Figure 7] Figure 7(a) is an enlarged plan view showing a missing portion and its surrounding edge in the component mounting substrate according to the first embodiment, and Figure 7(b) is an enlarged plan view showing a missing portion and its surrounding edge in the component mounting substrate according to a modified example. [Figure 8] Figure 8(a) is an end view of the component mounting board according to the second embodiment, and Figure 8(b) is an exploded end view of the component mounting board according to the second embodiment. [Figure 9] This is a plan view of a component mounting board according to the second embodiment. [Figure 10]Fig. 10(a) is an end view of a component mounting substrate according to the third embodiment, and Fig. 10(b) is an exploded end view of the component mounting substrate according to the third embodiment. [Figure 11] It is a schematic development view of a paper diaper provided with a component mounting substrate according to the third embodiment. [Figure 12] It is a plan view showing a modified example of the substrate. [Figure 13] It is a plan view showing a modified example of the substrate. [Figure 14] It is an end view of a component mounting substrate according to the fourth embodiment. [Figure 15] It is an exploded end view of the component mounting substrate according to the fourth embodiment. [Figure 16] It is an end view of a component mounting substrate according to a modified example of the fourth embodiment. [Figure 17] It is an end view of a component mounting substrate according to the fifth embodiment. [Figure 18] It is an exploded end view of the component mounting substrate according to the fifth embodiment. [Figure 19] It is an end view of a component mounting substrate according to the fifth embodiment, showing a state where the water-absorbing expansion material is expanded.

Embodiments for Carrying Out the Invention

[0009] 〔First Embodiment〕 Hereinafter, the first embodiment of the present invention will be described with reference to FIGS. 1 to 7(a). In all the drawings, the same components are denoted by the same reference numerals, and the description will be omitted as appropriate. Fig. 1 shows a cut end face along the B-B line in the region A (the region surrounded by the two-dot chain line frame) shown in Fig. 3, and Fig. 2 is an exploded end view of the corresponding part to Fig. 1.

[0010] As shown in FIGS. 1 to 3, the component mounting substrate 100 according to the present embodiment includes a substrate 10 having a base material 11, a first conductive pattern 30 formed on the base material 11, and a mounting component 50 electrically connected to the first conductive pattern 30, and a second conductive pattern 40 that complements the first conductive pattern 30 to form a circuit 60. In the substrate 11, the portion corresponding to the second conductive pattern 40 is a missing portion 12, and the second conductive pattern 40 is either soluble in liquid or becomes brittle when wetted by liquid.

[0011] Here, the second conductive pattern 40 being soluble in a liquid means that it dissolves or becomes weakened upon contact with a liquid, and more specifically, that it dissolves or becomes weakened upon contact with water (moisture). In other words, the second conductive pattern 40 is, for example, water-soluble. However, the second conductive pattern 40 may also be soluble in liquids such as organic solvents that do not contain water. In the substrate 11, the portion corresponding to the second conductive pattern 40 is the portion that corresponds to (overlaps with) the second conductive pattern 40 in a plan view (when viewed perpendicular to the surface of the component mounting substrate 100).

[0012] The second conductive pattern 40 dissolves or weakens due to sufficient contact with the liquid, causing the circuit 60 to lose its initial characteristics. By detecting the change in the characteristics (primarily impedance) of the circuit 60, it is possible to detect that the component mounting substrate 100 has been immersed in the liquid.

[0013] According to this embodiment, since the portion of the substrate 11 corresponding to the second conductive pattern 40 is a missing portion 12, the liquid can easily come into contact with the second conductive pattern 40 through the missing portion 12. Therefore, the second conductive pattern 40 can be more reliably dissolved when the component mounting substrate 100 is immersed in liquid. In other words, it is possible to more reliably detect when the component mounting substrate 100 is immersed in liquid.

[0014] The component mounting substrate 100 is, for example, a laminate formed in the shape of a flat plate. The planar shape of the component mounting substrate 100 is not particularly limited, but as an example, it can be substantially rectangular (for example, a rectangle with rounded corners) as shown in Figure 3. In this embodiment, the mounted component 50 is, for example, a chip for RFID applications (generally also called an IC chip), and the component mounting board 100 is an RFID tag.

[0015] In the following, when describing the positional relationships between the various components of the component mounting board 100, the upper side in Figure 1 will be referred to as the upper side or upward, and the opposite side will be referred to as the lower side or downward. Furthermore, the direction perpendicular to the vertical direction will be referred to as the horizontal direction. However, these directional definitions are for convenience only and do not limit the orientation of the component mounting board 100 during manufacturing or use. Furthermore, the left-right direction in Figures 1 to 3 is referred to as the X direction, and the up-down direction in Figure 3 is referred to as the Y direction. The X and Y directions are parallel to the plane direction of the component mounting substrate 100 (horizontal direction) and are perpendicular to the up-down direction in Figure 1 (direction perpendicular to the plane of the component mounting substrate 100).

[0016] In this embodiment, as shown in Figures 1 and 2, the component mounting substrate 100 further comprises a second substrate 21 positioned opposite the base material 11, and a second conductive pattern 40 is formed on the second substrate 21. More specifically, the component mounting substrate 100 includes, for example, a second substrate 20 in addition to the substrate 10 described above, the second substrate 20 having a second base material 21 and a second conductive pattern 40 formed on the second base material 21. With this configuration, since the component mounting board 100 includes both board 10 and the second board 20, it is possible to achieve a good balance between the structural strength of the component mounting board 100 and the reliability of detecting that the component mounting board 100 has been immersed in liquid. The second substrate 21 is, for example, soluble in liquid. This means that when the second substrate 21 holding the second conductive pattern 40 is dissolved due to sufficient contact with the liquid, if a slight external force is applied to the second conductive pattern 40, the second conductive pattern 40 will easily break or crack, and the circuit 60 will not be able to maintain its initial characteristics. In other words, it is possible to more reliably detect that the component mounting substrate 100 has been immersed in liquid. Here, the statement that the second base material 21 is soluble in a liquid means that the second base material 21 dissolves (dissolves) upon contact with the liquid. More specifically, for example, the liquid is one that contains water, and the second base material 21 dissolves upon contact with water (moisture). In other words, the second base material 21 is, for example, water-soluble. However, the second base material 21 may also be soluble in liquids such as organic solvents that do not contain water.

[0017] The second substrate 21 is composed of, for example, PVA (polyvinyl alcohol). By having the second substrate 21 composed of PVA, a structure can be realized in which the second substrate 21 dissolves well when the component mounting substrate 100 comes into contact with moisture. However, if the second base material 21 is water-soluble, the material of the second base material 21 is not limited to PVA, but may be, for example, polyvinylpyrrolidone, water-soluble polyester, water-soluble paper material, or sheet material derived from starch components.

[0018] The thickness of the second substrate 21 is not particularly limited, but is preferably, for example, 5 μm or more and 100 μm or less. If the thickness of the second substrate 21 is 5 μm or more, the second conductive pattern 40 can be stably supported by the second substrate 21 before the component mounting substrate 100 comes into contact with the liquid. If the thickness of the second substrate 21 is 100 μm or less, the second substrate 21 can dissolve quickly when the component mounting substrate 100 comes into contact with the liquid. If the thickness of the second substrate 21 is relatively thin, such as 5 μm, it is desirable to laminate a release separator made of paper or film material to the second substrate 21 during the manufacturing process of the component mounting substrate 100. This makes it possible to improve the handling of the thin second substrate 21, such as 5 μm. After the component mounting substrate 100 is completed, the release separator can be peeled off.

[0019] As shown in Figures 3 and 4, in this embodiment, the missing portion 12 is an opening formed in the base material 11. That is, the missing portion 12 penetrates through both the front and back surfaces of the base material 11. In the region where the missing portion 12 exists, the first conductive pattern 30 is not formed. The missing portion 12 may also be slit-shaped. More specifically, the substrate 10 has, for example, a pair of left and right cutouts 12, and the left and right cutouts 12 are arranged to be identical in shape to each other and are arranged symmetrically. More specifically, the cutouts 12 are formed in, for example, a substantially rectangular shape (e.g., a rectangle with rounded corners) that is elongated in the Y direction. However, the shape of the cutouts 12 is not particularly limited. Alternatively, for example, a part of the substrate 10 and other parts that are formed individually may be assembled by adjusting their positional relationship so that a cutout 12 is formed between these parts. In this case, the first conductive pattern 30 is composed of a combination of a part formed on one part of the substrate 10 and a part formed on the other part of the substrate 10.

[0020] In this embodiment, the first conductive pattern 30 includes, as an example, an antenna wiring section and a component mounting wiring section, which are described below.

[0021] The antenna wiring section has a first antenna wiring section located on the left side in Figure 4 and a second antenna wiring section located on the right side. The first antenna wiring section has, for example, a wide section 31a formed in a substantially rectangular shape that is elongated in the Y direction in a plan view, and a zigzag section 32a that is narrower than the wide section 31a and extends in the X direction while swaying in a zigzag pattern in the Y direction. The left end of the zigzag section 32a is connected to the wide section 31a, and the right end of the zigzag section 32a is connected to the component mounting wiring section. The second antenna wiring section is, for example, formed symmetrically to the first antenna wiring section and has a wide section 31b and a zigzag section 32b. The right end of the zigzag section 32b is connected to the wide section 31b, and the left end of the zigzag section 32b is connected to the component mounting wiring section.

[0022] The component mounting wiring section includes a linear pattern component 33a connected to the right end of the zigzag section 32a and extending in the X direction, a linear pattern component 34a positioned on the extension of the linear pattern component 33a with the left-side missing section 12 in between and extending in the X direction, a linear pattern component 34b connected to the right side of the linear pattern component 34a and extending in the X direction, and a linear pattern component 33b positioned on the extension of the linear pattern component 34b with the right-side missing section 12 in between and extending in the X direction. The component mounting wiring section further includes a connecting section 35 and annular pattern components 36a, 37a, 38a, 39a, 301a, 36b, 37b, 38b, 39b, and 301b, respectively, as described below. One end of the connecting portion 35 is connected to the boundary between the linear pattern component 34a and the linear pattern component 34b, and the connecting portion 35 extends from the boundary in one direction in the Y direction (downward in Figure 4) (i.e., it extends in the Y direction). The annular pattern component 36a is connected to the other end of the connecting portion 35 and extends to the left from the other end of the connecting portion 35 (i.e., it extends in the X direction). The annular pattern component 37a is positioned on the extension of the annular pattern component 36a with the left-side missing portion 12 in between and extends in the X direction. One end of the annular pattern component 38a is connected to the left end of the annular pattern component 37a, and the annular pattern component 38a extends in one direction in the Y direction (downward in Figure 4) from the left end of the annular pattern component 37a (i.e., it extends in the Y direction). The annular pattern component 39a is connected to the other end of the annular pattern component 38a and extends to the right from the other end of the annular pattern component 38a (i.e., it extends in the X direction). The annular pattern component 301a is positioned on the extension of the annular pattern component 39a with the left-side missing portion 12 in between and extends in the X direction. The annular pattern component 36b is connected to the other end of the connecting portion 35 and extends to the right from the other end of the connecting portion 35 (i.e., it extends in the X direction). The annular pattern component 37b is positioned on the extension of the annular pattern component 36b with the right-side missing portion 12 in between and extends in the X direction. One end of the annular pattern component 38b is connected to the right end of the annular pattern component 37b, and the annular pattern component 38b extends in one direction in the Y direction (downward in Figure 4) from the right end of the annular pattern component 37b (i.e., it extends in the Y direction). The annular pattern component 39b is connected to the other end of the annular pattern component 38b and extends to the left from the other end of the annular pattern component 38b (i.e., it extends in the X direction). The annular pattern component 301b is positioned on the extension of the annular pattern component 39b with the right-side missing portion 12 in between and extends in the X direction. The annular pattern component 301a and the annular pattern component 301b are arranged on each other's extensions.

[0023] As shown in Figure 5, the second substrate 20 has, for example, bridge portions 41a, 41b, 42a, 42b, 43a, and 43b extending in the X direction as the second conductive pattern 40. As shown in Figure 3, the bridge section 41a connects the right end of the linear pattern section 33a to the left end of the linear pattern section 34a. The bridge section 41b connects the right end of the linear pattern section 34b to the left end of the linear pattern section 33b. Thus, the linear pattern section 33a, bridge section 41a, linear pattern section 34a, linear pattern section 34b, bridge section 41b, and linear pattern section 33b form a linear pattern that extends linearly in the X direction and connects the first antenna wiring section and the second antenna wiring section. Bridge section 42a connects the right end of the annular pattern component 37a to the left end of the annular pattern component 36a. Bridge section 42b connects the right end of the annular pattern component 36b to the left end of the annular pattern component 37b. Bridge section 43a connects the right end of the annular pattern component 39a to the left end of the annular pattern component 301a. Bridge section 43b connects the right end of the annular pattern component 301b to the left end of the annular pattern component 39b. As a result, an annular pattern is formed by the annular pattern component 301a, bridge component 43a, annular pattern component 39a, annular pattern component 38a, annular pattern component 37a, bridge component 42a, annular pattern component 36a, annular pattern component 36b, bridge component 42b, annular pattern component 37b, annular pattern component 38b, annular pattern component 39b, bridge component 43b, and annular pattern component 301b. The annular pattern is formed in a substantially rectangular annular shape, for example, in a plan view. The annular pattern is discontinuous between the annular pattern component 301a and the annular pattern component 301b. That is, the annular pattern has an opening (an open annular shape). The connecting section 35 connects the linear pattern and the annular pattern to each other.

[0024] Here, each of the bridge sections 41a, 42a, and 43a is positioned across the left-side missing section 12, while each of the bridge sections 41b, 42b, and 43b is positioned across the right-side missing section 12. As shown in Figure 1, the bridge section 43a is installed between the annular pattern component 39a and the annular pattern component 301a, electrically connecting the annular pattern component 39a and the annular pattern component 301a to each other. Similarly, the bridge section 43b is installed between the annular pattern component 301b and the annular pattern component 39b, electrically connecting the annular pattern component 301b and the annular pattern component 39b to each other. Similarly, bridge section 41a is installed between linear pattern section 33a and linear pattern section 34a, electrically connecting them; bridge section 41b is installed between linear pattern section 34b and linear pattern section 33b, electrically connecting them; bridge section 42a is installed between annular pattern section 37a and annular pattern section 36a, electrically connecting them; and bridge section 42b is installed between annular pattern section 36b and annular pattern section 37b, electrically connecting them.

[0025] Thus, the second conductive pattern 40 (each of the bridge portions 41a, 41b, 42a, 42b, 43a, and 43b) is positioned across the missing portion 12 and is installed between the first portion of the first conductive pattern 30 and the second portion of the first conductive pattern 30, which is separated from the first portion with the missing portion 12 in between, thereby electrically connecting the first portion and the second portion. In other words, each of the second conductive patterns 40 is a bridge wiring. In a plan view, the second conductive pattern 40 extends from a part of the peripheral edge of the missing portion 12, across the missing portion 12, and into the other part of the peripheral edge of the missing portion 12.

[0026] The second substrate 20 may have portions other than the bridge portions 41a to 43b as the second conductive pattern 40, but the bridge portions 41a to 43b are wiring portions that constitute the circuit 60. In other words, the parts of the second conductive pattern 40 corresponding to the missing portion 12 (bridge portions 41a to 43b) are wiring portions that constitute the circuit 60, and are not electrodes or the like.

[0027] The second conductive pattern 40 (each of the bridge portions 41a, 41b, 42a, 42b, 43a and 43b) is a portion of the first conductive pattern 30 that is connected to the second conductive pattern 40 (linear pattern components 33a, 33b, 34a, 34b, Circular pattern component It is preferable that the second conductive pattern 40 is formed to be wider than 36a, 36b, 37a, 37b, 39a, 39b, 301a, 301b). By doing so, when aligning the substrate 10 and the second substrate 20 and assembling the substrate 10 and the second substrate 20 together, and when electrically connecting the second conductive pattern 40 and the first conductive pattern 30 to each other, even if the substrate 10 and the second substrate 20 are slightly misaligned relative to each other in the planar direction, the second conductive pattern 40 can be properly aligned and connected to the first conductive pattern 30. Furthermore, if the first conductive pattern 30 is, for example, a pattern derived from metal foil and has a low impedance, and the second conductive pattern 40 is a coating film formed by printing, it is expected that the impedance of the second conductive pattern 40 will be higher than the impedance of the metal foil pattern. However, as mentioned above, forming the second conductive pattern 40 wider than the portion of the first conductive pattern 30 that connects to the second conductive pattern 40 is advantageous because it allows for matching the impedances of the first conductive pattern 30 and the second conductive pattern 40 at a low level. However, the second conductive pattern 40 may be formed to have the same width as the portion of the first conductive pattern 30 that is connected to the second conductive pattern 40, or it may be formed to be narrower than that portion.

[0028] The length of each second conductive pattern 40 is such that the portion of the first conductive pattern 30 connected to the second conductive pattern 40 (linear pattern components 33a, 33b, 34a, 34b, Circular pattern component It is preferable that the length is longer than the width dimension of 36a, 36b, 37a, 37b, 39a, 39b, 301a, 301b), preferably twice or more the length of the said width dimension, and more preferably three times or more the length of the said width dimension. In particular, it is preferable that the length of the portion of each second conductive pattern 40 that is installed between the first conductive patterns 30 (between the first and second portions) is longer than the width dimension of the portion of the first conductive pattern 30 that is connected to the second conductive pattern 40, more preferably twice or more the width dimension, and more preferably three times or more the width dimension.

[0029] In this embodiment, not only is the second substrate 21 soluble in the liquid, but as described above, the second conductive pattern 40 is also soluble in the liquid or becomes weakened upon contact with the liquid. Here, the second conductive pattern 40 being soluble in liquid means, as described above, that upon contact with a liquid, the second conductive pattern 40 dissolves (melts) or becomes weakened (changes to the point where it can easily break, even if it does not reach a state of complete dissolution). More specifically, for example, the second conductive pattern 40 dissolves or becomes weakened upon contact with water (moisture). This property of the second conductive pattern 40 dissolving or becoming weakened upon contact with water is referred to as "the second conductive pattern 40 being water-soluble." However, the second conductive pattern 40 may also be soluble or weakened in liquids such as organic solvents that do not contain moisture. More specifically, the second conductive pattern 40 and the second substrate 21 have the property of being soluble or weakened in the same type of liquid (for example, water).

[0030] In this embodiment, the second conductive pattern 40 contains a resin having hot-melt properties and is electrically and mechanically connected to the first conductive pattern 30 by hot-melt bonding. In other words, the second conductive pattern 40 is fusion-bonded to the first conductive pattern 30, and the second conductive pattern 40 and the first conductive pattern 30 are not merely in contact. The second conductive pattern 40 is a coating film comprising, for example, a conductive filler and a binder containing a thermoplastic resin. The thermoplastic resin preferably exhibits hot-melt properties at 50°C or higher. The second conductive pattern 40 is composed of, for example, a water-soluble conductive paste, and is a water-soluble silver pattern. More specifically, the second conductive pattern 40 is composed of a dry material in which conductive particles (e.g., silver particles) are kneaded into a thermoplastic resin with an organic solvent.

[0031] The thickness of the second conductive pattern 40 is not particularly limited, but is preferably, for example, 10 μm or more and 50 μm or less. By having a thickness of 10 μm or more of the second conductive pattern 40, stable characteristics of the circuit 60 can be obtained before the component mounting substrate 100 comes into contact with the liquid. By having a thickness of 50 μm or less of the second conductive pattern 40, the second conductive pattern 40 can be rapidly dissolved or weakened when the component mounting substrate 100 comes into contact with the liquid.

[0032] In this embodiment, since the second conductive pattern 40 as bridge wiring is arranged at multiple locations in the circuit 60, it is possible to increase the possibility that when the component mounting substrate 100 comes into contact with liquid, one of the second conductive patterns 40 will break, one of the second conductive patterns 40 will crack, or one of the second conductive patterns 40 will dissolve or become brittle.

[0033] In this embodiment, the substrate 11 is insoluble in liquid. Therefore, even if the component mounting substrate 100 unintentionally comes into contact with liquid during storage, etc., it is possible to suppress the dissolution of the substrate 11, which could cause the first conductive pattern 30 to break or crack, thereby changing the characteristics of the circuit 60. The base material 11, which is insoluble in liquids, can be made of, for example, paper or a resin film. The resin material constituting this resin film is not particularly limited, but examples include polyethylene, polystyrene, polypropylene, or polyester. However, the present invention is not limited to this example, and the base material 11 may be soluble in liquid. The thickness of the base material 11 is not particularly limited, but is preferably, for example, 10 μm or more and 75 μm or less. By having a thickness of 10 μm or more of the base material 11, the first conductive pattern 30 can be stably supported by the base material 11, and sufficient structural strength can be obtained for the component mounting substrate 100. By having a thickness of 75 μm or less for the base material 11, good flexibility of the component mounting substrate 100 can be obtained.

[0034] In this embodiment, the first conductive pattern 30 is also insoluble in liquid. Therefore, even if the component mounting substrate 100 unintentionally comes into contact with liquid during storage, etc., it is possible to suppress changes in the characteristics of the circuit 60 due to the dissolution of the first conductive pattern 30. In particular, it is preferable that the majority of the circuit 60 is composed of the first conductive pattern 30 which is insoluble in liquid. However, the present invention is not limited to this example, and the first conductive pattern 30 may be soluble in liquid. The first conductive pattern 30 is composed of, for example, a metal foil. More specifically, the first conductive pattern 30 is composed of a metal foil whose pattern is formed by etching. Examples of metal materials include aluminum, gold, silver, and copper. However, the first conductive pattern 30 may be, for example, a printed coating. When the first conductive pattern 30 is printed, the first conductive pattern 30 is a coating film comprising, for example, a conductive filler and a binder containing a thermoplastic resin. The conductive filler is composed of, for example, gold, silver, copper, or carbon. Examples of thermoplastic resins include polyester resin, acrylic resin, urethane resin, etc. The thickness of the first conductive pattern 30 is not particularly limited, but is preferably, for example, 5 μm or more and 30 μm or less.

[0035] As shown in Figures 1 and 2, in this embodiment, a soluble layer 22, which is an adhesive layer soluble in liquid, is formed on the surface of the second substrate 21 facing the substrate 11 (one surface 21a), and the second conductive pattern 40 is formed on the second substrate 21 via the soluble layer 22. Therefore, as the soluble layer 22 dissolves through sufficient contact with the liquid, the second substrate 21 also comes into contact with the liquid. Here, the soluble layer 22 being soluble in a liquid means that it dissolves upon contact with the liquid, and more specifically, that it dissolves upon contact with water (moisture). In other words, the soluble layer 22 is, for example, water-soluble. However, the soluble layer 22 may also be soluble in liquids such as organic solvents that do not contain water. More specifically, the soluble layer 22 and the second base material 21 are soluble in the same type of liquid (for example, water). The adhesive that forms the water-soluble (or aqueous) soluble layer 22 is not particularly limited, but examples include starch paste, gum arabic paste, and aqueous acrylic emulsion. An example of an aqueous acrylic emulsion is to prepare it by copolymerizing acrylic monomers containing carboxyl groups and adding alcohol or polyethylene oxide. The soluble layer 22 may also be composed of two or more water-soluble (or aqueous) adhesives. The soluble layer 22 not only adheres the second substrate 21 and the second conductive pattern 40 to each other, but also adheres the second substrate 21 to the substrate 11 and to the first conductive pattern 30.

[0036] The thickness of the soluble layer 22 is not particularly limited, but is preferably 5 μm or more and 50 μm or less, and more preferably 10 μm or more and 30 μm or less. By having a thickness of 10 μm or more of the soluble layer 22, good adhesion between the second substrate 21 and the second conductive pattern 40, between the second substrate 21 and the substrate 11, and between the second substrate 21 and the first conductive pattern 30 can be achieved before the soluble layer 22 comes into contact with the liquid. By having a thickness of 30 μm or less, the soluble layer 22 can dissolve quickly when it comes into contact with a liquid.

[0037] The external shapes of the substrate 10 (base material 11) and the second substrate 20 (second base material 21) may be the same or different. In this embodiment, for example, the external shapes of the substrate 10 (base material 11) and the second substrate 20 (second base material 21) are the same and coincide in plan view. Furthermore, the external shape of the second substrate 20 (second base material 21) and the external shape of the soluble layer 22 may be the same as or different from each other. In this embodiment, for example, the external shape of the second substrate 20 (second base material 21) and the external shape of the soluble layer 22 are the same as each other and coincide in a plan view.

[0038] Although detailed illustrations are omitted, the mounted component 50 comprises, for example, a component body formed by resin molding of an element, and mounting terminals provided along the lower surface of the component body, with the element and the mounting terminals being electrically connected to each other inside the resin mold. The number of mounting terminals on the mounting component 50 is not particularly limited, but in this embodiment, the mounting component 50 has two mounting terminals, each of which is electrically connected to the first conductive pattern 30. More specifically, one mounting terminal of the mounting component 50 is electrically connected to the right end of the annular pattern component 301a, and the other mounting terminal of the mounting component 50 is electrically connected to the left end of the annular pattern component 301b. In other words, the mounting component 50 is positioned across the annular pattern component 301a and the annular pattern component 301b. In this way, the mounted component 50 is mounted on the component mounting wiring section.

[0039] The antenna wiring section transmits and receives signals to and from external devices (e.g., an RFID reader / writer), for example. Signals or radio waves received by the antenna wiring section from the external device are input to the mounted component 50. The mounted component 50 transmits signals to the external device via the component mounting wiring section and the antenna wiring section. In addition, a part or all of the component mounting wiring section may also function as an antenna in cooperation with the antenna wiring section. The mounted component 50 is a passive type that operates using power excited from an external device via the antenna wiring section.

[0040] In this embodiment, the second conductive pattern 40 may dissolve, break, or crack due to contact between the component mounting substrate 100 and the liquid, resulting in the loss or deterioration of the communication function of the component mounting substrate 100. By detecting this loss or deterioration of the communication function, an external device can detect that the component mounting substrate 100 has come into contact with the liquid.

[0041] Next, the manufacturing method of the component mounting substrate according to this embodiment will be explained using Figures 6(a) to 6(c). Figure 6(a) is a plan view showing the substrate 10 before the missing portion 12 is formed. Figures 6(b) and 6(c) show the process of forming the missing portion 12 on the substrate 10, and show the cut end surface along line BB in region A (the region enclosed by the dashed-dot frame) shown in Figure 6(a).

[0042] The manufacturing method for a component mounting substrate according to this embodiment comprises the steps of preparing a substrate 10, preparing a second substrate 20, and assembling the substrate 10 and the second substrate 20 together. In the process of preparing the substrate 10, as shown in Figure 6(c), the substrate 10 is prepared having a base material 11, a first conductive pattern 30 formed on the base material 11, and mounting components 50 electrically connected to the first conductive pattern 30. In the process of preparing the second substrate 20, a second substrate 20 (see Figure 2) is prepared, which has a second base material 21 that is soluble in liquid and a second conductive pattern 40 formed on the second base material 21. In the process of assembling the substrate 10 and the second substrate 20, the first conductive pattern 30 and the second conductive pattern 40 complementarily form the circuit 60, and the substrate 10 and the second substrate 20 are assembled such that the parts of the substrate 11 corresponding to the second conductive pattern 40 become missing parts 12. That is, the substrate 10 and the second substrate 20 are aligned facing each other and then bonded together. This yields the component mounting board 100 according to this embodiment.

[0043] The bonding of substrate 10 and second substrate 20 can be performed by heat-pressing (thermal lamination) the substrates 10 and 20 together. For example, the process of heat-pressing substrate 10 and second substrate 20 together is preferably carried out at a temperature of 80°C to 150°C, more preferably 100°C to 120°C. The heating time can be, for example, about 5 to 10 seconds. Furthermore, the heat-pressing process is preferably carried out under pressure conditions of 0.3 MPa to 3.0 MPa, and more preferably under pressure conditions of 1.0 MPa to 2.0 MPa. By bonding the substrate 10 and the second substrate 20 in this manner, the second conductive pattern 40 containing a resin with hot-melt properties can be well electrically and mechanically connected to the first conductive pattern 30.

[0044] More specifically, as shown in Figure 6(b), a portion of the substrate 10 is punched out by a punching process, and as shown in Figure 6(c), a missing portion 12 is formed in the base material 11 and the first conductive pattern 30 is divided into multiple parts. After this, the substrate 10 and the second substrate 20 are assembled together (assembly process). Since a substrate 10 having a missing portion 12 and a first conductive pattern 30 divided into multiple parts can be obtained by punching, commercially available RFID tags and the like can be used as the substrate 10, and the component mounting substrate 100 can be manufactured at a lower cost.

[0045] In the punching process, the direction of the punching operation is preferably from the side of the substrate 10 facing the second substrate 20 (one side 11a of the base material 11) to the opposite side (the other side 11b of the base material 11). In other words, as shown in Figure 6(b), the cutting blade 110 is moved in the direction of the arrow in Figure 6(b) to punch out the substrate 10, thereby processing the substrate 10 into the shape shown in Figure 6(c). As a result, even if burrs are generated on the cut end surface of the first conductive pattern 30, these burrs will be positioned to stand upright on the opposite side of the second substrate 20 (i.e., the second conductive pattern 40 side), allowing the second conductive pattern 40 to be easily brought into close contact with the first conductive pattern 30, thereby improving the conductivity of the second conductive pattern 40 with respect to the first conductive pattern 30. Furthermore, the cutting blade 110 is formed in a plan view annular shape corresponding to the missing portion 12.

[0046] In this embodiment, as shown in Figure 7(a), the positions of the ends 30a and 30b of the first conductive pattern 30 coincide with the position of the end 12a of the missing portion 12. As described above, by punching out a portion of the substrate 10 to form a missing portion 12 in the substrate 10, a structure in which the positions of the ends 30a and 30b of the first conductive pattern 30 and the position of the end 12a of the missing portion 12 can be easily realized. When a portion of the substrate 10 is punched out by a die-cutting process, the shoulder portion of the edge of the first conductive pattern 30 (the upper right corner of the annular pattern component 39a and the upper left corner of the annular pattern component 39b in Figures 1 and 2) becomes rounded, so a bridge is formed there. Department When 41a-43b are laminated, the bridge Department Cutting and damage to parts 41a to 43b can be suppressed. Furthermore, of the ends 30a and 30b of the first conductive patterns 30 which are interconnected via the second conductive pattern 40, only one side (for example, only end 30a) may coincide with the end 12a of the missing portion 12, while the other side (for example, end 30b) may be spaced apart from end 12a.

[0047] Furthermore, as shown in Figure 7(b), in the present invention, both ends 30a and 30b of the first conductive pattern 30 may be spaced apart from the end 12a of the missing portion 12. That is, in the first conductive pattern 30, the ends 30a and 30b that are close to the missing portion 12 may be spaced apart from the end 12a of the missing portion 12. In this case, the distance D (Figure 7(b)) from end 12a to ends 30a and 30b of the missing portion 12 is preferably 0.1 mm or more, and also preferably 0.2 mm or more. In this case, the first conductive pattern 30 can be manufactured by forming a pattern on the substrate 11 such that the ends 30a and 30b are spaced apart from the end 12a. In this case, no burrs (burrs caused by punching) are generated at the ends 30a and 30b, so there is no bridging of the first conductive pattern 30. Department When 41a-43b are laminated, the bridge Department Cutting and damage to parts 41a to 43b can be suppressed. In the above explanation, it was stated that the missing portion 12 is formed by punching, and it can be said that the application of a die or punch is the most typical method. However, other methods such as laser processing can also be applied to obtain the missing portion 12.

[0048] [Second Embodiment] Next, a second embodiment will be described using Figures 8(a) to 9. The component mounting board 100 according to this embodiment differs from the component mounting board 100 according to the first embodiment described above in the respects described below, and is otherwise configured in the same way as the component mounting board 100 according to the first embodiment described above.

[0049] In this embodiment, the component mounting substrate 100 does not have a soluble layer 22 (Figure 1, etc.), but instead has a bonding sheet 80 as shown in Figure 8(a), etc. The bonding sheet 80 is an adhesive sheet having tackiness or an adhesive sheet having bonding properties. The bonding sheet 80 is insoluble in liquids. However, the bonding sheet 80 may be soluble in liquids. As shown in Figures 8(a) and 8(b), in this embodiment, the second conductive pattern 40 is formed directly on the second substrate 21. The substrate 10 and the second substrate 20 are bonded to each other via a bonding sheet 80 (adhesive sheet or adhesive sheet). As shown in Figure 8(a), in the second substrate 21, the region encompassing the formation area of ​​the second conductive pattern 40 faces the missing portion 12 via a second missing portion 81 formed in the bonding sheet 80 (adhesive sheet or adhesive sheet). As described above, for example, both ends of the second conductive pattern 40 protrude from the missing portion 12 in a plan view, so the "region in the second substrate 21 that includes the formation region of the second conductive pattern 40" is, more specifically, the region that includes the formation region of the portion of the second conductive pattern 40 excluding both ends. In this embodiment, the second conductive pattern 40 is formed directly on the second substrate 21 rather than on the soluble layer 22, so it can be easily formed even with conventional screen printing.

[0050] As shown in Figures 8(a) to 9, the second missing portion 81, in a plan view, encompasses, for example, the entire area of ​​the missing portion 12. In a plan view, the bonding sheet 80 is interposed between the substrate 10 and the second substrate 20 in the area excluded from the missing portion 12, the connection between the first conductive pattern 30 and the second conductive pattern 40. For example, the bonding sheet 80 has a left second missing portion 81 that encompasses the left missing portion 12, and a right second missing portion 81 that encompasses the right missing portion 12. The left second missing portion 81 completely encompasses, for example, the formation regions of a plurality of second conductive patterns 40 (bridge portions 41a, 42a, 43a) corresponding to the left missing portion 12, and the right second missing portion 81 completely encompasses, for example, the formation regions of a plurality of second conductive patterns 40 (bridge portions 41b, 42b, 43b) corresponding to the right missing portion 12. However, one second missing portion 81 may encompass multiple (for example, two) missing portions 12, and may also completely encompass all the formation regions of the second conductive patterns 40. Furthermore, the end of the second conductive pattern 40 may overlap with the bonding sheet 80, as long as the connection between the first conductive pattern 30 and the second conductive pattern 40 is not obstructed. In the example shown in Figure 9, the second missing portion 81 is a notched portion formed in the bonding sheet 80. However, the second missing portion 81 may also be an opening formed in the bonding sheet 80. Alternatively, the component mounting substrate 100 may have a plurality of bonding sheets 80 that are independent of each other, and the gaps between these bonding sheets 80 may constitute the second missing portion 81.

[0051] The external shape of the substrate 10 (base material 11) and the external shape of the bonding sheet 80 (excluding the second missing portion 81) may be the same as or different from each other. Similarly, the external shape of the second substrate 20 (second base material 21) and the external shape of the bonding sheet 80 (excluding the second missing portion 81) may be the same as or different from each other. In this embodiment, for example, the external shapes of the substrate 10 (base material 11), the second substrate 20 (second base material 21), and the bonding sheet 80 (excluding the second missing portion 81) are equal to each other and coincide in a plan view.

[0052] [Third Embodiment] Next, a third embodiment will be described using Figures 10(a) to 11. The component mounting board 100 according to this embodiment differs from the component mounting board 100 according to the first embodiment described above in the respects described below, and is otherwise configured in the same way as the component mounting board 100 according to the first embodiment described above.

[0053] As shown in Figures 10(a) and 10(b), the component mounting substrate 100 according to this embodiment includes a first nonwoven fabric layer 92 arranged along the side of the substrate 10 opposite to the side of the second substrate 20 (the other side 11b of the base material 11), and a second nonwoven fabric layer 91 arranged along the side of the second substrate 20 opposite to the side of the substrate 10 (the other side 21b of the second base material 21). However, the present invention is not limited to this example, and the component mounting substrate 100 may include only one of the first nonwoven fabric layer 92 and the second nonwoven fabric layer 91. That is, the component mounting substrate 100 includes at least one of the first nonwoven fabric layer 92 and the second nonwoven fabric layer 91. Since the component mounting substrate 100 is equipped with at least one of the first nonwoven fabric layer 92 and the second nonwoven fabric layer 91, the first nonwoven fabric layer 92 or the second nonwoven fabric layer 91 can absorb and retain liquid (e.g., water), so that the liquid can be sufficiently supplied to the second substrate 21, the second conductive pattern 40, and the soluble layer 22. Moreover, the seepage of the second substrate 21, the second conductive pattern 40, and the soluble layer 22 dissolved in the liquid can be suppressed by the first nonwoven fabric layer 92 or the second nonwoven fabric layer 91, thereby reducing discomfort for the user. The first nonwoven fabric layer 92 and the second nonwoven fabric layer 91 are more preferably made of materials with high water absorption (high water retention) properties (low basis weight).

[0054] The first nonwoven fabric layer 92 and the second nonwoven fabric layer 91 are preferably arranged in a region that includes the missing portion 12 in a plan view. The first nonwoven fabric layer 92 and the second nonwoven fabric layer 91 may be arranged over the entire surface of the component mounting substrate 100, or they may be selectively arranged in a portion of the component mounting substrate 100.

[0055] Furthermore, an adhesive sheet (adhesive layer 94) is provided on at least one of the surfaces of the first nonwoven fabric layer 92 opposite to the substrate 10 (the bottom surface in Figures 10(a) and 10(b)) and the surface of the second nonwoven fabric layer 91 opposite to the second substrate 20 (the top surface in Figures 10(a) and 10(b)). This allows the component mounting board 100 to be easily attached to the object using an adhesive sheet.

[0056] In this embodiment, of the first nonwoven fabric layer 92 and the second nonwoven fabric layer 91, the adhesive layer 94 is provided on the first nonwoven fabric layer 92. The adhesive layer 94 is provided on the first nonwoven fabric layer 92, for example, in the form of a double-sided tape 93 with a release sheet 95. In this way, by peeling the release sheet 95 from the adhesive layer 94 of the double-sided tape 93, the component mounting substrate 100 can be attached to the object to be mounted using the adhesive layer 94.

[0057] The adhesive layer 94 is preferably insoluble in liquid, thereby preventing the component mounting substrate 100 from detaching from the object to be mounted even if it comes into contact with liquid. The adhesive layer 94 has a third missing portion 93a that corresponds to the missing portion 12. This allows liquid to be supplied to the missing portion 12 via the third missing portion 93a, making it possible to easily dissolve the second substrate 21, the second conductive pattern 40, and the soluble layer 22. Preferably, the third missing portion 93a completely encloses the missing portion 12 in a plan view.

[0058] The component mounting substrate 100 according to this embodiment is, for example, attached to an absorbent article (for example, the disposable diaper 300 shown in Figure 11) that is configured to absorb liquid. In Figure 11, the side of the disposable diaper 300 that comes into contact with the wearer's skin is shown. When the wearer urinates into the disposable diaper 300, and the second base material 21, the second conductive pattern 40, and the soluble layer 22 dissolve due to the urine, this can be detected, thereby enabling the detection of the wearer's urination. In other words, the component mounting board 100 is used as a urination sensor to notify the caregiver when it is time to change the disposable diaper 300.

[0059] As shown in Figure 11, for example, the disposable diaper 300 comprises a rear portion 310 positioned on the wearer's back, a front portion 320 positioned on the wearer's front, a connecting portion 330 connecting the rear portion 310 and the front portion 320, and a plurality of hook-and-loop fastener portions 340 formed on the sides of the rear portion 310. The disposable diaper 300 can be attached to the wearer by connecting both sides of the rear portion 310 and the front portion 320 via the hook-and-loop fastener portions 340. In the disposable diaper 300, an absorbent material 350 capable of absorbing liquid is formed on the surface that comes into contact with the wearer's skin. The absorbent body 350 extends in the front-rear direction, for example, across the rear portion 310, the front portion 320, and the connecting portion 330. When the disposable diaper 300 is worn by the wearer, the absorbent material 350 is positioned in contact with the wearer's excretory area, and when the wearer urinates, the urine is absorbed by the absorbent material 350. The component mounting substrate 100 is preferably located on the side of the absorber 350 that comes into contact with the wearer's skin. The presence of the third missing portion 93a allows urine to be discharged towards the disposable diaper 300 (rather than towards the body), thereby reducing discomfort for the wearer. In addition to the configuration of the component mounting substrate 100 according to the first embodiment, Figures 10(a) and 10(b) show an example that includes a first nonwoven fabric layer 92, a second nonwoven fabric layer 91, and an adhesive layer 94 (double-sided tape 93). 2 In addition to the configuration of the component mounting substrate 100 according to the embodiment, it may also include a first nonwoven fabric layer 92, a second nonwoven fabric layer 91, and an adhesive layer 94 (double-sided tape 93). Furthermore, the absorbent article on which the component mounting board 100 is attached is not limited to a disposable diaper 300, but may also be, for example, a urine pad (not shown) attached to underwear.

[0060] [Fourth Embodiment] Next, a fourth embodiment will be described using Figures 14 and 15. The component mounting board 100 according to this embodiment differs from the component mounting board 100 according to the first embodiment described above in the respects described below, and is otherwise configured in the same way as the component mounting board 100 according to the first embodiment described above.

[0061] In this embodiment, as shown in Figures 14 and 15, the soluble layer 22 is formed on the surface of the substrate 11 opposite to the surface on which the first conductive pattern 30 is formed (the other surface 11b). In other words, on the substrate 11, the soluble layer 22, which is soluble in liquid, is formed on the surface opposite to the surface on which the first conductive pattern 30 is formed (the other surface 11b). Furthermore, the component mounting substrate 100 does not have a second substrate 21, and the second conductive pattern 40 is formed across the first conductive pattern 30 and the soluble layer 22. With this configuration, when the side of the component mounting substrate 100 opposite to the side where the first conductive pattern 30 is formed (the other side 11b) is immersed in the liquid, the liquid can be made to come into sufficient contact with the soluble layer 22 and, consequently, with the second conductive pattern 40. Therefore, it is possible to more reliably detect that the component mounting substrate 100 has been immersed in the liquid.

[0062] As shown in Figures 14 and 15, the soluble layer 22 is located on the other side 11b of the base material 11, while a portion of the second conductive pattern 40 is laminated on the first conductive pattern 30. In other words, the substrate 10, including the base material 11 and the first conductive pattern 30, is positioned between a portion of the second conductive pattern 40 and the soluble layer 22 in the vertical direction. Furthermore, in this embodiment, a double-sided tape 98 is directly laminated on one surface 22a of the soluble layer 22, and the soluble layer 22 is bonded to the substrate 11 via the double-sided tape 98. Furthermore, in the double-sided tape 98, the portion corresponding to the second conductive pattern 40 is a missing fourth missing portion 98a. The second conductive pattern 40 is arranged, for example, spanning the missing portion 12 and the fourth missing portion 98a. The fourth missing portion 98a is formed to have the same shape as the missing portion 12 in a plan view, for example. In a plan view, the region where the fourth missing portion 98a exists coincides with the region where the missing portion 12 exists. More specifically, the fourth missing portion 98a is an opening formed in the double-sided tape 98. The double-sided tape 98 has, for example, a pair of left and right fourth missing portions 98a, where the left fourth missing portion 98a corresponds to the left missing portion 12, and the right fourth missing portion 98a corresponds to the right missing portion 12. The second conductive pattern 40 is formed, for example, over the peripheral edge of the missing portion 12 on the substrate 10, the inner surface of the missing portion 12, the inner surface of the fourth missing portion 98a, and one surface 22a of the soluble layer 22.

[0063] For example, as shown in Figure 14, the bridge portion 43a of the second conductive pattern 40 extends, in a side view, across a portion of the peripheral edge of the left-side missing portion 12, a portion of the inner surface of the missing portion 12, a portion of the inner surface of the left-side fourth missing portion 98a, a portion of one surface 22a of the soluble layer 22 corresponding to the missing portion 12, and the other portion of the peripheral edge of the missing portion 12. Similarly, for example, the bridge portion 43b extends, in a side view, across a portion of the peripheral edge of the right-side missing portion 12, a portion of the inner surface of the missing portion 12, a portion of the inner surface of the right-side fourth missing portion 98a, a portion of one surface 22a of the soluble layer 22 corresponding to the missing portion 12, and the other portion of the peripheral edge of the missing portion 12. In this manner, in this embodiment as well, the bridge portion 43a electrically connects the annular pattern component 39a and the annular pattern component 301a. Similarly, the bridge portion 43b electrically connects the annular pattern component 301b and the annular pattern component 39b.

[0064] In this embodiment, when forming the second conductive pattern 40, the second conductive pattern 40 is printed onto the substrate 10 to which the soluble layer 22 has been previously attached via double-sided tape 98.

[0065] <Modified form of the fourth embodiment> Next, a modified example of the fourth embodiment will be described using Figure 16.

[0066] In this modified example, the second conductive pattern 40 is electrically connected to the first conductive pattern 30 via a water-insoluble conductive paste 65 interposed between the second conductive pattern 40 and the first conductive pattern 30, which is different from the component mounting substrate 100 according to the fourth embodiment described above. In other respects, it is configured the same as the component mounting substrate 100 according to the fourth embodiment described above. With this configuration, the connection resistance between the second conductive pattern 40 and the first conductive pattern 30 can be reduced. Therefore, the conductivity of the second conductive pattern 40 to the first conductive pattern 30 can be improved.

[0067] More specifically, it is preferable that the conductive paste 65 is interposed between each of the aforementioned bridge portions 41a, 41b, 42a, 42b, 43a, and 43b and the component mounting wiring portion corresponding to each of the bridge portions 41a to 43b. In the example shown in Figure 16, the conductive paste 65 is interposed, for example, between the bridge portion 43a and the annular pattern component 39a, and between the bridge portion 43a and the annular pattern component 301a. Similarly, the conductive paste 65 is interposed, for example, between the bridge portion 43b and the annular pattern component 39b, and between the bridge portion 43b and the annular pattern component 301b. This makes it possible to achieve a configuration in which the bridge section 43a provides good electrical connection between the annular pattern component 39a and the annular pattern component 301a, and the bridge section 43b provides good electrical connection between the annular pattern component 301b and the annular pattern component 39b. Although not shown in the diagram, for example, the conductive paste 65 may be interposed between the bridge portion 41a and the linear pattern component 33a, between the bridge portion 41a and the linear pattern component 34a, between the bridge portion 41b and the linear pattern component 34b, and between the bridge portion 41b and the linear pattern component 33b. Similarly, for example, the conductive paste 65 may be interposed between the bridge portion 42a and the annular pattern component 37a, between the bridge portion 42a and the annular pattern component 36a, between the bridge portion 42b and the annular pattern component 36b, and between the bridge portion 42b and the annular pattern component 37b.

[0068] The conductive paste 65 includes, for example, conductive particles with a particle size of 1 μm to 5 μm and a thermosetting resin. The conductive particles are, as an example, silver particles or a core made of silica with a silver coating on its surface. Here, This variant In this case, when forming the conductive paste 65, heat treatment (drying treatment) is performed on the conductive paste 65 after printing. Also, if the first conductive pattern 30 is made of aluminum, an aluminum oxide film (not shown) may be formed on its surface. and, This variant According to this, when the conductive paste 65 is heat-treated, stress is generated in the region where the conductive paste 65 is formed on the surface of the first conductive pattern 30 due to the shrinkage of the thermosetting resin contained in the conductive paste 65, so that the aluminum oxide film can be broken in that region. Therefore, the second conductive pattern 40 can be electrically connected to the first conductive pattern 30 via the conductive paste 65.

[0069] [Fifth Embodiment] Next, a fifth embodiment will be described using Figures 17 to 19. Figures 17 and 19 show, as an example, a state in which the component mounting board 100 is attached to the disposable diaper 300. The component mounting board 100 according to this embodiment differs from the component mounting board 100 according to the fourth embodiment and its modified form in the respects described below, and is otherwise configured in the same way as the component mounting board 100 according to the fourth embodiment and its modified form.

[0070] In this embodiment, as shown in Figures 17 and 19, the component mounting substrate 100 further includes a water-absorbing and expanding material 70. When the water-absorbing and expanding material 70 expands due to water absorption, it presses the base material 11 or the second conductive pattern 40 in a direction perpendicular to the surface of the base material 11, causing the second conductive pattern 40 to break.

[0071] According to this embodiment, the component mounting substrate 100 is equipped with a water-absorbing and expanding material 70 that expands upon water absorption, and the expanded water-absorbing and expanding material 70 presses the base material 11 or the second conductive pattern 40 in a direction perpendicular to the surface of the base material 11. As a result, an external force is applied to the second conductive pattern 40, causing it to break. By detecting a change in the characteristics of the circuit 60 (for example, primarily the loss of function of the circuit 60), it is possible to indirectly detect the occurrence of the breakage in the second conductive pattern 40, thereby detecting that the component mounting substrate 100 has been immersed in liquid. Furthermore, since the portion of the base material 11 corresponding to the second conductive pattern 40 is a missing portion 12, that is, a part of the second conductive pattern 40 is not protected by the base material 11, the second conductive pattern 40 can be more reliably broken by the water-absorbing and expanding material 70. Moreover, since liquid can be sufficiently supplied to the water-absorbing and expanding material 70 through the missing portion 12, the water-absorbing and expanding material 70 can absorb water sufficiently and expand. Thus, according to this embodiment, it becomes possible to more reliably detect that the component mounting substrate 100 has been immersed in liquid.

[0072] The water-absorbing and expanding material 70 is, for example, a compressed cellulose sponge. However, the present invention is not limited to this example, and the water-absorbing and expanding material 70 may be a member that expands by absorbing water other than a compressed cellulose sponge, such as a water-absorbing polymer. Furthermore, the water-absorbing and expanding material 70 is attached to the other surface 22b of the soluble layer 22, for example, via double-sided tape 75.

[0073] Furthermore, as shown in Figures 17 and 18, the component mounting substrate 100 includes, for example, a first water-conducting sheet 85 located on one side 11a of the base material 11, and a second water-conducting sheet 86 located on the opposite side of the base material 11 from the one side 11a, with a water-absorbing and expanding material 70 in between. As a result, the first water-conducting sheet 85 and the second water-conducting sheet 86 can each absorb liquid (e.g., water), so that the liquid can be sufficiently supplied to the second conductive pattern 40, the soluble layer 22, and the water-absorbing and expanding material 70. It is preferable that each of the first water-conducting sheet 85 and the second water-conducting sheet 86 is positioned in a region that, in a plan view, includes the water-absorbing and expanding material 70. Each of the first water-conducting sheet 85 and the second water-conducting sheet 86 may be positioned across the entire surface of the component mounting substrate 100, or it may be selectively positioned in a portion of the component mounting substrate 100. In this embodiment, as an example, each of the first water-conducting sheet 85 and the second water-conducting sheet 86 is positioned in a region that, in a plan view, includes the entire first conductive pattern 30.

[0074] Furthermore, the component mounting substrate 100 includes, for example, a first constraint sheet (in this embodiment, a first water-permeable sheet 87 described later) located on one side 11a of the substrate 10, and a second constraint sheet (in this embodiment, a second water-permeable sheet 88 described later) located on the other side 11b. The first and second constraint sheets constrain at least the periphery of the placement area of ​​the second conductive pattern 40 on the substrate 10. In this embodiment, as an example, the first and second constraint sheets constrain at least the periphery of the placement area of ​​the first conductive pattern 30 on the substrate 10. In this context, the area surrounding the placement region of the second conductive pattern 40 is the area surrounding the entire missing portion 12. With this configuration, as shown in Figure 19, the water-absorbing and expanding material 70 can press against a portion of the base material 11, causing a relative displacement between the two portions of the base material 11 that sandwich the missing portion 12. More specifically, the expanded water-absorbing and expanding material 70 presses, for example, the portion of the base material 11 located between the left and right missing portions 12 in the direction perpendicular to the surface of the base material 11 (upward in Figure 8 in this embodiment). As a result, the portion of the base material 11 located between the left and right missing portions 12 is displaced upward compared to the other portions of the base material 11. As a result, the bridge sections 41a, 42a, and 43a, which span the missing section 12 on the left, and the bridge sections 41b, 42b, and 43b, which span the missing section 12 on the right, each break. In the example shown in Figure 19, the entire soluble layer 22 is shown to be dissolved.

[0075] In this embodiment, the component mounting substrate 100 includes, for example, a first water-permeable sheet 87 as a first restraining sheet and a second water-permeable sheet 88 as a second restraining sheet. As a result, the liquid can be quickly supplied to the second conductive pattern 40, the soluble layer 22, and the water-absorbing and expanding material 70 by the first water-permeable sheet 87 or the second water-permeable sheet 88. More specifically, in both cases where the side of the component mounting substrate 100 on which the first water-permeable sheet 87 is located is mainly immersed in the liquid, and where the side of the component mounting substrate 100 on which the second water-permeable sheet 88 is located is mainly immersed in the liquid, the liquid can be quickly supplied to the second conductive pattern 40, the soluble layer 22, and the water-absorbing and expanding material 70 by the first water-permeable sheet 87 or the second water-permeable sheet 88. The first permeable sheet 87 is, for example, laminated on the first water-conducting sheet 85, and the second permeable sheet 88 is, for example, placed below the second water-conducting sheet 86. Furthermore, when the component mounting substrate 100 is attached to an absorbent article configured to absorb liquid (for example, the disposable diaper 300 shown in Figures 17 and 19), the second water-permeable sheet 88 is attached to the absorbent article via double-sided tape 99 (or hook-and-loop fastener portion).

[0076] The first water-conducting sheet 85 and the second water-conducting sheet 86 are not particularly limited, but one example is a highly absorbent (highly water-retaining) nonwoven fabric of rayon with a basis weight of, for example, 40 g / m². 2 More than 80g / m 2 Preferably 50g / m 2 More than 70g / m 2 The following applies. Note that the first water-conducting sheet 85 and the second water-conducting sheet 86 may each be made of, for example, pulp, cotton, or hemp. The first permeable sheet 87 and the second permeable sheet 88 are not particularly limited, but for example, they may be made of polyester, polypropylene, or polyethylene terephthalate, with a basis weight of, for example, 5 g / m². 2 More than 100g / m 2 Preferably 10 g / m 2 More than 50g / m 2 The following nonwoven fabric is used. This ensures good water permeability for both the first water-permeable sheet 87 and the second water-permeable sheet 88.

[0077] Although each embodiment has been described above with reference to the drawings, these are merely examples of the present invention, and various other configurations can also be adopted.

[0078] For example, although the above description illustrates an example where the mounted component 50 is an RFID chip, the present invention is not limited to this example, and the mounted component 50 may be other electronic components, such as capacitors or resistors. Furthermore, the component mounting board 100 may be applied not only to RFID tag applications but also to NFC (Near Field Communication).

[0079] Furthermore, although the above description explained an example in which the missing portion 12 is an opening, the missing portion 12 may also be a notched portion formed in the base material 11, as shown in Figure 12. Furthermore, as shown in Figure 13, the substrate 10 is divided into multiple parts (for example, three parts: a first part 10A, a second part 10B, and a third part 10C), and the gaps between these multiple parts may be missing parts 12.

[0080] Furthermore, although the above describes an example in which the second conductive pattern 40 is installed between a first portion of the first conductive pattern 30 and a second portion of the first conductive pattern 30 that is separated from the first portion by a missing portion 12 in between, the present invention is not limited to this example, and the second conductive pattern 40 may not be installed between the first conductive patterns 30, but may simply be connected to the first conductive pattern 30. A simple example is a circuit 60 shown in Figure 1 in which the left half is made up of the first conductive pattern 30 and the right half is made up of the second conductive pattern 40.

[0081] This embodiment encompasses the following technical concepts. (1) A substrate having a base material, a first conductive pattern formed on the base material, and a mounting component electrically connected to the first conductive pattern, A second conductive pattern that constitutes a circuit complementary to the first conductive pattern, Equipped with, In the substrate, the portion corresponding to the second conductive pattern is a missing portion. The second conductive pattern is a component mounting substrate that is soluble in liquid or becomes brittle when wetted by liquid. (2) The component mounting board described in (1), wherein the portion in the second conductive pattern facing the missing portion is a wiring portion that constitutes the circuit. (3) The component mounting substrate according to (1) or (2), wherein the missing portion is an opening hole or a notched portion formed in the base material. (4) The component mounting substrate according to any one of (1) to (3), wherein the second conductive pattern is arranged across the missing portion and is installed between a first portion of the first conductive pattern and a second portion of the first conductive pattern that is separated from the first portion with the missing portion in between, thereby electrically connecting the first portion and the second portion. (5) The liquid contains water, The second conductive pattern is composed of a water-soluble conductive paste. The first conductive pattern is composed of metal foil, The component mounting substrate according to any one of (1) to (4), wherein the second conductive pattern is electrically connected to the first conductive pattern via a water-insoluble conductive paste interposed between the second conductive pattern and the first conductive pattern. (6) The component mounting substrate according to any one of (1) to (4), wherein the second conductive pattern contains a resin having hot-melt properties and is electrically and mechanically connected to the first conductive pattern by hot-melt bonding. (7) The component mounting substrate according to any one of (1) to (6), wherein the substrate is insoluble in the liquid. (8) The component mounting substrate according to any one of (1) to (7), wherein the first conductive pattern is insoluble in the liquid. (9) Further comprising a second substrate arranged opposite to the substrate, A component mounting substrate according to any one of (1) to (8), wherein the second conductive pattern is formed on the second substrate. (10) In the second substrate, a soluble layer, which is an adhesive layer soluble in the liquid, is formed on the surface facing the substrate. The component mounting substrate according to (9), wherein the second conductive pattern is formed on the second substrate via the soluble layer. (11) The second conductive pattern is formed directly on the second substrate, The first substrate and the second substrate are bonded together via an adhesive sheet or bonding sheet. The component mounting substrate according to (9), wherein the region of the second substrate that includes the region for forming the second conductive pattern faces the missing portion through the adhesive sheet or the second missing portion formed in the adhesive sheet. (12) A component mounting substrate according to any one of (9) to (11), comprising at least one of a first nonwoven fabric layer disposed along the surface of the substrate opposite to the second substrate side, and a second nonwoven fabric layer disposed along the surface of the second substrate opposite to the substrate side. (13) The component mounting substrate according to (12), wherein an adhesive sheet is provided on at least one of the surfaces of the first nonwoven fabric layer opposite to the substrate side and the surfaces of the second nonwoven fabric layer opposite to the second substrate side. (14) The component mounting substrate according to any one of (1) to (8), wherein a soluble layer that is soluble in the liquid is formed on the surface of the substrate opposite to the surface on which the first conductive pattern is formed. (15) A component mounting board according to any one of (1) to (14), wherein the position of the end of the first conductive pattern coincides with the position of the end of the missing portion. (16) The component mounting substrate according to any one of (1) to (14), wherein in the first conductive pattern, the end adjacent to the missing portion is spaced apart from the end of the missing portion. [Explanation of Symbols]

[0082] 10 circuit boards 10A 1st part 10B 2nd part 10C 3rd part 11 Base material 11a One side 11b The other side 12 Missing parts 12a end 20 Second board 21 Second base material 21a One side 21b The other side 22 Soluble layer 30 First conductive pattern 30a, 30b end 31a, 31b Wide section 32a, 32b Zigzag section 33a, 33b, 34a, 34b Linear pattern component 35 Connecting part 36a, 36b, 37a, 37b, 38a, 38b, 39a, 39b, 301a, 301b Annular pattern component 40 Second conductive pattern 41a, 41b, 42a, 42b, 43a, 43b Bridge section 50 mounted components 60 circuits 65 Conductive Paste 70 Water-absorbing and expanding material 75 Double-sided tape 80 Bonding sheets (adhesive sheets, bonding sheets) 81. Second Missing Section 85. First water intake sheet 86. Second water intake sheet 87. First permeable sheet 88. Second permeable sheet 91 Second nonwoven layer 92 1st nonwoven layer 93 Double-sided tape 93a Third Missing Section 94 Adhesive layer 95 Release Sheet 98, 99 Double-sided tape 98a Fourth Missing Section 100-component mounting board 110 Cutting blade 300 disposable diapers 310 Rear 320 front 330 Connection section 340 hook-and-loop fastener section 350 absorbent

Claims

1. A substrate having a base material, a first conductive pattern formed on the base material, and a mounting component electrically connected to the first conductive pattern, A second conductive pattern that constitutes a circuit complementary to the first conductive pattern, Equipped with, The mounted component is positioned on the side of the first conductive pattern opposite to the side of the substrate, In the substrate, the portion corresponding to the second conductive pattern is a missing portion. The second conductive pattern is a component mounting substrate that is soluble in liquid or becomes brittle when wetted by liquid.

2. The component mounting substrate according to claim 1, wherein the portion of the second conductive pattern facing the missing portion is a wiring portion that constitutes the circuit.

3. The component mounting substrate according to claim 1 or 2, wherein the missing portion is an opening hole or a notched portion formed in the base material.

4. The component mounting substrate according to any one of claims 1 to 3, wherein the second conductive pattern is arranged across the missing portion and is installed between a first portion of the first conductive pattern and a second portion of the first conductive pattern that is separated from the first portion with the missing portion in between, thereby electrically connecting the first portion and the second portion.

5. A substrate having a base material, a first conductive pattern formed on the base material, and a mounting component electrically connected to the first conductive pattern, A second conductive pattern that constitutes a circuit complementary to the first conductive pattern, Equipped with, In the substrate, the portion corresponding to the second conductive pattern is a missing portion. The second conductive pattern is either soluble in liquid or becomes brittle when wetted by liquid. The aforementioned liquid contains water, The second conductive pattern is composed of a water-soluble conductive paste. The first conductive pattern is composed of metal foil, The component mounting substrate wherein the second conductive pattern is electrically connected to the first conductive pattern via a water-insoluble conductive paste interposed between the second conductive pattern and the first conductive pattern.

6. The component mounting substrate according to any one of claims 1 to 4, wherein the second conductive pattern contains a resin having hot-melt properties and is electrically and mechanically connected to the first conductive pattern by hot-melt bonding.

7. The component mounting substrate according to any one of claims 1 to 6, wherein the substrate is insoluble in the liquid.

8. The component mounting substrate according to any one of claims 1 to 7, wherein the first conductive pattern is insoluble in the liquid.

9. The system further comprises a second substrate arranged opposite to the aforementioned substrate, A component mounting substrate according to any one of claims 1 to 8, wherein the second conductive pattern is formed on the second substrate.

10. In the second substrate, a soluble layer, which is an adhesive layer soluble in the liquid, is formed on the surface facing the substrate. The component mounting substrate according to claim 9, wherein the second conductive pattern is formed on the second substrate via the soluble layer.

11. The second conductive pattern is formed directly on the second substrate, The first substrate and the second substrate are bonded together via an adhesive sheet or bonding sheet. The component mounting substrate according to claim 9, wherein in the second substrate, the region encompassing the region for forming the second conductive pattern faces the missing portion through the adhesive sheet or the second missing portion formed in the adhesive sheet.

12. A component mounting substrate according to any one of claims 9 to 11, comprising at least one of a first nonwoven fabric layer disposed along the surface of the substrate opposite to the second substrate side, and a second nonwoven fabric layer disposed along the surface of the second substrate opposite to the substrate side.

13. The component mounting substrate according to claim 12, wherein an adhesive sheet is provided on at least one of the surfaces of the first nonwoven fabric layer opposite to the substrate side and the surfaces of the second nonwoven fabric layer opposite to the second substrate side.

14. The component mounting substrate according to any one of claims 1 to 8, wherein a soluble layer that is soluble in the liquid is formed on the surface of the substrate opposite to the surface on which the first conductive pattern is formed.

15. A component mounting substrate according to any one of claims 1 to 14, wherein the position of the end of the first conductive pattern coincides with the position of the end of the missing portion.

16. The component mounting substrate according to any one of claims 1 to 14, wherein in the first conductive pattern, the end adjacent to the missing portion is spaced apart from the end of the missing portion.

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