JP2020137934A - Mounting structure of device equipped with biological electrode - Google Patents

Abstract

To provide a mounting structure of a device that can be easily made without difficult processes such as routing of wiring on front and back sides and via processing of a base material.SOLUTION: A mounting structure of a device includes: a base material with a thickness of 0.2 mm or less; an electronic component provided on one side of the base material; an electrode provided on the one side of the base material for acquiring biological information; wiring provided on the one side of the base material for electrically conducting the electronic component and the electrode; and reinforcement resin for reinforcing the base material, the wiring, the electronic component, and a part of the electrode by covering them. The surface of the electrode is not covered with the reinforcement resin, but is exposed from the reinforcement resin, and the height of the surface of the electrode is larger than the height of the surface of the reinforcement resin for reinforcing the base material, the wiring, the electronic component, and the electrode.SELECTED DRAWING: Figure 1

Description

The present invention relates to a device mounting structure in which electrodes for acquiring biological information are provided on a flexible base material.

In the field of electronics, research and development and practical application of wearable electronic devices used by integrating electronic devices with clothes or attaching them to the skin are progressing. Such wearable devices are required to be flexible, and in that case, there is an increasing need to use flexible materials for printed circuit boards and wiring materials. Taking advantage of the flexibility of the device, a device that is attached to a living body and provides information such as electrocardiogram and myoelectricity of the living body has also been put into practical use.

It is often reported that a thermoplastic film such as PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PI (polyimide), or a urethane film having elasticity is used as the flexible base material. It is difficult to make the wiring multi-layered, and it is common to use the surface layer of the film for the wiring.

In addition, the electrodes for acquiring biometric information must be in close contact with the skin, and the wiring for connecting the bioelectrode and parts such as ICs for processing the signals of the bioelectrode is based on the above film. When used, wiring can only be formed on the surface layer. For this reason, it is necessary to devise various ways to route the wiring.

As one of the wiring forming methods in that case, a method of providing a via hole in the base material has been reported (see, for example, Patent Document 1).

International Publication No. 2018/123732

As described in Patent Document 1, by providing via holes in a flexible thermoplastic film base material, it is possible to communicate electrical signals between the front surface and the back surface of the film. On the other hand, it is necessary to form the via hole of the film base material by a laser or a drill, and further to plate the inner wall surface of the via hole with a metal such as copper, which increases the number of steps for forming the wiring board.

The present invention provides a device mounting structure provided with a bioelectrode, which can be easily created without difficult processes such as routing wiring to the front and back and via processing of a base material. The purpose is.

In order to achieve the above object, the mounting structure of the device according to the present invention is configured as follows.
According to the first aspect of the present invention
With a base material with a thickness of 0.2 mm or less
Electronic components provided on one side of the base material and
An electrode provided on one side of the base material to acquire biological information,
A wiring provided on one side of the base material and electrically conducting the electronic component and the electrode,
A reinforcing resin that covers and reinforces the base material, the wiring, the electronic components, and a part of the electrodes.
With
The surface of the electrode is not covered with the reinforcing resin and is exposed from the reinforcing resin, and the height of the surface of the electrode is such that the base material, the wiring, the electronic component, and the electrode are reinforced. Provided is a device mounting structure characterized by being higher than the surface of the reinforcing resin.

According to the device mounting structure according to the present invention, wiring formation and electronic component mounting are completed on one side of the base material. As a result, the mounting structure of the device can be easily manufactured without any difficult process such as routing the wiring to the front and back and via processing of the base material. Furthermore, the height of the surface of the electrode for acquiring biometric information is higher than that of the base material, wiring, electronic components, and reinforcing resin that reinforces the electrodes, so when the wiring formation and component mounting surface is attached to the living body, , The electrodes for acquiring biological information are more likely to adhere to the living body. As a result, it becomes possible to acquire biometric information with higher accuracy.

It is sectional drawing which shows the cross-sectional structure of the mounting structure of the device which concerns on embodiment. It is a schematic diagram of an electrode for acquiring biological information.

The device mounting structure according to the first aspect includes a base material having a thickness of 0.2 mm or less and
Electronic components provided on one side of the base material and
An electrode provided on one side of the base material to acquire biological information,
A wiring provided on one side of the base material and electrically conducting the electronic component and the electrode,
A reinforcing resin that covers and reinforces the base material, the wiring, the electronic components, and a part of the electrodes.
With
The surface of the electrode is not covered with the reinforcing resin and is exposed from the reinforcing resin, and the height of the surface of the electrode is such that the base material, the wiring, the electronic component, and the electrode are reinforced. Higher than the surface of the reinforcing resin.

According to the above configuration, the height of the surface of the electrode for acquiring biological information is higher than that of the base material, wiring, electronic components, and reinforcing resin for reinforcing the electrodes, so that the wiring forming and component mounting surface is attached to the living body. When attached, the electrodes for acquiring biological information are more likely to adhere to the living body. As a result, it becomes possible to acquire biometric information with higher accuracy.

In the device mounting structure according to the second aspect, in the first aspect, the base material may be a thermoplastic resin.

In the first or second aspect of the device mounting structure according to the third aspect, the wiring may be formed by applying an Ag-based paste.

The device mounting structure according to the fourth aspect is the electrode in which the biological information is acquired in any one of the first to third aspects.
At least a part of the back surface of the electrode has conductivity that conducts with the wiring.
The back surface of the electrode may be electrically conductive with the wiring.

The device mounting structure according to the fifth aspect is the electrode for acquiring the biological information in the fourth aspect.
The back surface of the electrode and the wiring material forming the wiring may be electrically conducted by a solder alloy.

In the fifth aspect of the device mounting structure according to the sixth aspect, the solder alloy may have a melting point of 160 ° C. or lower.

In the device mounting structure according to the seventh aspect, in any one of the first to sixth aspects, the electrode for acquiring biometric information may contain silver.

In any of the first to seventh aspects of the device mounting structure according to the eighth aspect, the storage elastic modulus of the reinforcing resin may be 100 MPa · s or less.

Hereinafter, the mounting structure of the device according to the embodiment will be described with reference to the accompanying drawings. In the attached drawings, the same reference numerals are given to substantially the same members.

(Embodiment)
FIG. 1 is a cross-sectional view showing a cross-sectional structure of the mounting structure 10 of the device according to the embodiment. In addition. In FIG. 1, a part thereof is enlarged and shown in order to clarify the characteristics of the device mounting structure 10.
As shown in FIG. 1, the device mounting structure 10 according to the embodiment has an electrode 1 for acquiring biological information on one surface of a film-like base material 2 having a thickness of 0.2 mm or less. It includes an electronic component 3, a wiring 4, and a reinforcing resin 5 for covering and reinforcing a part of the base material 2, the wiring 4, the electronic component 3, and the electrode 1. The wiring 4 electrically conducts the electronic component 3 and the electrode 1. However, the surface of the electrode 1 is not covered with the reinforcing resin. That is, the electrode 1 is exposed from the reinforcing resin 5 so that it can come into contact with the living body (skin) 7.

The mounting structure 10 of this device includes at least two or more electrodes 1 for acquiring biological information, a sensing electrode and a reference electrode.
Further, the surface of the electrode 1 in contact with the living body reinforces the base material 2, the wiring 4, the electronic component 3 and the electrode 1 so that the electrode 1 for acquiring the biological information can easily adhere to the living body (skin) 7. It is higher than the upper surface of the reinforcing resin 5.
Further, a cover film 6 for fixing the device mounting structure 10 to the living body (skin) or for protecting the device mounting structure 10 from the environment such as water vapor and water droplets may be provided as needed.

FIG. 2 is a schematic view of the electrode 1 for acquiring biological information.
The electrode 1 for acquiring biological information is in contact with the living body (skin) 7, and the electrode front surface 11 and the electrode back surface 13 (surface in contact with wiring) are electrically conductive through the electrode base body 12. .. As a result, the signal of biological information via the living body (skin) 7 is transmitted from the surface of the electrode in contact with the skin (electrode surface 11) to the surface of the electrode in contact with the wiring 4 (electrode back surface 13), and the signal is further processed through the wiring 4. The signal of biological information is transmitted to the electronic component 3.

According to the mounting structure of the device according to the embodiment, the bioelectrode that is in close contact with the living body is provided, and biometric information such as electrocardiogram and myoelectricity can be obtained from the bioelectrode that is in close contact with the living body. Further, a flexible film-like resin such as PET, PEN, or PI is used as the wiring base material. In the mounting structure of this device, wiring formation and electronic component mounting are completed on one side of the base material. As a result, the mounting structure of the device can be easily manufactured without any difficult process such as routing the wiring to the front and back and via processing of the base material.
Further, as described above, the surface of the electrode 1 in contact with the living body is higher than the upper surface of the electronic component 3, the wiring 4, and the reinforcing resin 5 covering a part of the electrode 1 with respect to the surface of the base material 2. In this case, when the base material 2 has flexibility and the surface of the base material 2 is curved, the height of the electrode 1 and the height of the reinforcing resin 5 are compared along the curved surface of the surface of the base material 2. To do.

Here, the configuration and material specifications of the device mounting structure 10 will be described in more detail.

<Base material>
As the film-like base material 2 having a thickness of 0.2 mm or less, a thermoplastic resin or a thermosetting resin can be used depending on the application. As the thermoplastic resin, various resins such as polyimide (PI), polycarbonate (PC), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), urethane-based, olefin-based, styrene-based, and amide-based elastomers are used. be able to.
As the thermosetting resin, various resins such as epoxy, urethane, and silicone acrylic resin can be used.
Further, a stretchable material such as an elastomer is used depending on the material of the base material 2 and the necessity of stretching and contracting the device.
Further, the base material 2 is preferably a thermoplastic resin from the viewpoint of cost.

<Electrode>
Next, the electrode 1 will be described.
The electrode surface 11 for acquiring biological information may be a standard Ag / AgCl conductive hydrogel such as that used for electrocardiography, or carbon or Ag fiber, or carbon or Ag is kneaded into the electrode surface 11. A dry conductive material such as an elastomer may be provided.
Further, a part of the back surface 13 of the electrode, which is the surface of the electrode 1 in contact with the wiring material, needs to be conductive, and by electrically conducting with the wiring 4, the electric signal acquired from the living body 7 is transmitted to the wiring 4. It is being transmitted. The conductive material is not particularly limited, but more preferably a metal capable of forming a solder alloy such as Sn, Cu, Ag, and Au is used.

The material of the base body 12 of the electrode 1 is not limited as long as there is an electrical conduction path between the electrode front surface 11 and the electrode back surface 13. It may be a single metal or carbon conductive material, or it may be a thermoplastic or thermosetting resin whose surface is plated with a conductive material.
Although the electrode 1 is shown as a cylindrical shape in FIG. 2, it is not limited to such a shape. For example, the base body 12 of the electrode 1 may have a columnar shape connecting the electrode front surface 11 and the electrode back surface 13. Further, it is sufficient that the electrode front surface 11 and the electrode back surface 13 can be electrically connected, and the base material 12 of the electrode 1 may have a linear or planar shape such as a wire shape.

<Electronic components>
As the electronic component 3, in addition to active elements such as ICs, passive elements such as resistors, capacitors, and inductors are used.

<Wiring>
The wiring material used for the wiring 4 is not limited as long as it is a conductive material, but may be Cu used for general wiring. More preferable in terms of having flexibility are Ag-based particles, which may be formed by applying Ag-based particles and drying or curing them. For example, after applying the Ag-based paste on the base material 2, it can be dried at a high temperature such as 120 ° C. to form the wiring 4 on the base material 2. The Ag-based paste can be applied by a printing method such as screen printing.

<Reinforcing resin>
As the reinforcing resin 5 that covers and reinforces the base material 2, the wiring 4, the electronic component 3, and a part of the electrode 1, both a thermosetting resin and a thermoplastic resin can be used, but it is more flexible in that it has flexibility. Suitable are silicone, urethane, and olefin resins, epoxy single or composite resins designed and blended to have flexibility, and the reinforced resin 5 has a storage elasticity of 100 MPa · s or less. Is preferable.

<Cover film>
The cover film 6 is used for fixing the device mounting structure 10 to the living body (skin) 7 and for protecting the device mounting structure 10 from the environment such as water vapor and water droplets, and various resins may be used. it can. As the cover film 6, silicone, urethane, and olefin-based resins are suitable from the viewpoint of flexibility and biocompatibility.

(Implementation method)
Next, a method of creating a device mounting structure according to the embodiment will be described.
(1) As the film-like base material 1, PET having a thickness of 0.1 mm is used.
(2) As the wiring material used for the wiring 4, a conductive paste (product number: CI-1036 manufactured by EMS) containing an Ag-based filler as a main component of conduction was used. The wiring 4 is formed on the base material 1 by drawing on the base material 1 by screen printing and then drying at 120 ° C. for 15 minutes, for example.
(3) Further, as the electrode 1 for acquiring biological information, a Sn cylinder having a diameter of 5 mm and a height of 0.4 mm is used as a base material of the electrode 1, and the electrode surface 11 has Ag / AgCl conductivity. Paste the hydrogel.
(4) Next, Sn and Bi are configured at the positions of the electrodes provided on the back surface 13 of the electrode and the wiring of the base material 2 for joining the electronic component 3 such as an active or passive element and the wiring. A solder paste composed of a solder alloy having a melting point of 139 ° C. and a flux component is supplied by screen printing. Next, the electrode 1 and the electronic components 3 such as active and passive elements are mounted at predetermined positions, the temperature is raised to 175 ° C. using a reflow furnace, and the base material 2 and various electronic components 3 are joined by soldering. ..
Here, the alloy of the solder paste is selected from the viewpoint of the melting point and reliability of the material constituting the base material 2. For the base material 2 having a heat resistance of 120 ° C. or lower, such as polyurethane, it is desirable to use a solder alloy having a melting point of 120 ° C. or lower, which is composed of Sn, Bi, and In. Further, a thermosetting resin for reinforcement may be mixed with the flux component.

(5) Further, the reinforcing resin 5 is applied to the base material 2, the wiring 4, and various electronic components 3 so that the electrode surface 11 is higher than the reinforcing resin 5 on the entire surface of the mounting structure of the device. In this case, the electrode surface 11 is coated with the reinforcing resin 5 so as to be exposed without being covered with the reinforcing resin 5. When the reinforcing resin 5 is higher than the electrode surface 11, when the reinforcing resin 5 and the skin 7 come into contact with each other, the adhesion between the electrode surface 11 and the skin 7 tends to decrease, and as a result, the accuracy of the acquired biological information decreases. , Not desirable.
As described above, the device mounting structure 10 can be configured.

As described above, according to the method for manufacturing the mounting structure of the device in the present embodiment, there is no difficult process such as routing the wiring to the front and back and via processing of the base material, and the biometric information can be easily acquired. A device mounting structure with possible bioelectrodes can be made.

Moreover, although the present invention has been described in detail based on the above specific examples, the present invention is not limited to the above specific examples, and any modification or modification is possible as long as it does not deviate from the scope of the present invention.

It should be noted that the present disclosure includes appropriately combining any of the various embodiments and / or examples described above, and the respective embodiments and / or embodiments. The effects of the examples can be achieved.

The mounting structure of the device provided with the bioelectrode according to the present invention is a problem when a film-like base material having a thickness of 0.2 mm or less is used and an electrode for acquiring biometric information is provided, which is a problem in the wiring and mounting method. It is possible to solve the problem of simplification. That is, the mounting structure of the device provided with the bioelectrode according to the present invention provides a useful mounting structure of the bioelectrode that achieves both a simple manufacturing process and acquisition of highly accurate biometric information.

1 Electrode 2 Base material 3 Electronic component 4 Wiring 5 Reinforcing resin 6 Cover film 7 Living body (skin)
10 Device mounting structure 11 Electrode front surface 12 Electrode base 13 Electrode back surface

Claims (8)

With a base material with a thickness of 0.2 mm or less
Electronic components provided on one side of the base material and
An electrode provided on one side of the base material to acquire biological information,
A wiring provided on one side of the base material and electrically conducting the electronic component and the electrode,
A reinforcing resin that covers and reinforces the base material, the wiring, the electronic components, and a part of the electrodes.
With
The surface of the electrode is not covered with the reinforcing resin and is exposed from the reinforcing resin, and the height of the surface of the electrode is such that the base material, the wiring, the electronic component, and the electrode are reinforced. Device mounting structure that is higher than the surface of the reinforcing resin. The device mounting structure according to claim 1, wherein the base material is a thermoplastic resin. The device mounting structure according to claim 1 or 2, wherein the wiring is formed by applying an Ag-based paste. In the electrode for acquiring biological information,
At least a part of the back surface of the electrode has conductivity that conducts with the wiring.
The device mounting structure according to any one of claims 1 to 3, wherein the back surface of the electrode is electrically conductive with the wiring. In the electrode for acquiring biological information,
The device mounting structure according to claim 4, wherein the back surface of the electrode and the wiring material forming the wiring are electrically conducted by a solder alloy. The device mounting structure according to claim 5, wherein the solder alloy has a melting point of 160 ° C. or lower. The device mounting structure according to any one of claims 1 to 6, wherein the electrode for acquiring biometric information contains silver. The device mounting structure according to any one of claims 1 to 7, wherein the storage elastic modulus of the reinforcing resin is 100 MPa · s or less.

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