JP2022081415A - Biological sensor - Google Patents

Abstract

To provide a biological sensor capable of stably acquiring an electrocardiogram waveform even during exercise.SOLUTION: A biological sensor according to the present invention, which is stuck on an organism so as to acquire a biological signal, comprises a body, a base material that is provided on the organism side of a body, and an electrode that is provided on a surface on the organism side of the base material. A rate of breaking elongation of the base material is in the range of 30-500%, and a static friction coefficient of the electrode is in the range of 3.0-7.0.SELECTED DRAWING: Figure 1

Description

The present invention relates to a biosensor.

In medical institutions such as hospitals and clinics, nursing care facilities, homes, and the like, biosensors that measure biometric information such as electrocardiogram waveforms, pulse waves, electroencephalograms, and myoelectricity are used. The biosensor is equipped with a bioelectrode that contacts the living body and acquires the biometric information of the subject. When measuring the biometric information, the biosensor is attached to the skin of the subject and the bioelectrode is attached to the skin of the subject. Make contact. Biological information is measured by acquiring electrical signals related to biological information with bioelectrodes.

As such a biosensor, for example, a garment for measuring biometric information provided with a biocontact type electrode using a stretchable conductor sheet containing at least conductive fine particles and a flexible resin binder as a conductive member inside the garment. Is disclosed (see, for example, Patent Document 1). The biocontact type electrode attached to this biometric information measurement garment has an area of the electrode surface of 1 square centimeter or more, and the static friction coefficient between the surface of the biocontact type electrode and dry skin is 0.4 or more and 2.0 or less. And.

International Publication No. 2019/0446449

However, in the biological information measurement garment of Patent Document 1, the biological contact type electrode does not have adhesiveness, and the biological contact type electrode is sandwiched between the skin of the subject and the base material of the biological information measurement garment when worn. As a result, the position of the biocontact type electrode is fixed. Therefore, there is a problem that the position of the biological contact type electrode is easily displaced due to the movement of clothes and the movement of the skin of the subject during exercise such as walking or movement, and noise is likely to be generated in the electrocardiogram during exercise.

One aspect of the present invention is to provide a biosensor capable of stably acquiring an electrocardiogram waveform even during exercise.

One aspect of the biological sensor according to the present invention is a biological sensor attached to a living body to acquire a biological signal, which is a housing, a base material provided on the living body side of the housing, and the base material. It comprises an electrode provided on the surface on the living body side, the breaking elongation rate of the base material is 30% to 500%, and the static friction coefficient of the electrode is 3.0 to 7.0.

One aspect of the biosensor according to the present invention can stably acquire an electrocardiogram waveform even during exercise.

It is a perspective view which shows the structure of the biological sensor which concerns on embodiment of this invention. It is an exploded perspective view of FIG. FIG. 1 is a cross-sectional view taken along the line I-I of FIG. It is a top view which shows the structure of a sensor part. It is an exploded perspective view of a part of the sensor part of FIG. It is explanatory drawing which shows the state which attached the biosensor to the skin of a living body (subject). It is explanatory drawing which shows an example of the electrocardiogram waveform without noise. It is a figure explaining the SN ratio of the electrocardiogram waveform.

Hereinafter, embodiments of the present invention will be described in detail. In addition, in order to facilitate understanding of the description, the same reference numerals are given to the same components in each drawing, and duplicate description is omitted. In addition, the scale of each member in the drawing may differ from the actual scale. In the present specification, "-" indicating a numerical range means that, unless otherwise specified, the numerical values described before and after the numerical range are included as the lower limit value and the upper limit value.

<Biosensor>
The biosensor according to this embodiment will be described. The living body means a human body and animals such as cows, horses, pigs, chickens, dogs, and cats. The biosensor according to the present embodiment can be suitably used for a living body, especially for a human body. The biosensor according to the present embodiment is a stick-on biosensor that is attached to the skin, which is a part of a living body, to measure biological information. In this embodiment, a case where the living body is a human will be described as an example.

1 is a perspective view showing the configuration of a biological sensor according to the present embodiment, FIG. 2 is an exploded perspective view of FIG. 1, and FIG. 3 is a sectional view taken along the line I-I of FIG. As shown in FIG. 1, the biosensor 1 is a plate-shaped (sheet-shaped) member formed in a substantially elliptical shape in a plan view. As shown in FIGS. 2 and 3, the biosensor 1 has a housing (cover member) 10, a foam sheet 20, an electrode 30, a supporting adhesive sheet 40, and a sensor unit 50, and is supported from the housing 10 side. It is formed by laminating the housing 10, the foamed sheet 20, the electrode 30, and the supporting adhesive sheet 40 in this order toward the adhesive sheet 40 side. The biological sensor 1 attaches the foam sheet 20, the electrode 30, and the supporting adhesive sheet 40 to the skin 2 which is a living body, and acquires a biological signal from the skin 2 via the electrode 30. The biosensor 1 may have a release paper 60 on the side where the foam sheet 20, the electrode 30, and the supporting adhesive sheet 40 are attached to the living body when not in use, and the release paper 60 may be peeled off when in use. It can be used by sticking it on the surface of the skin 2.

The housing 10, the foamed sheet 20, and the supporting adhesive sheet 40 have substantially the same outer shape in a plan view. The sensor unit 50 is installed on the support adhesive sheet 40 and is housed in the storage space S formed by the housing 10 and the foam sheet 20.

In the present specification, a three-dimensional Cartesian coordinate system in three-axis directions (X-axis direction, Y-axis direction, Z-axis direction) is used, the short-axis direction of the biosensor is the X-axis direction, and the long-axis direction is the Y-axis direction. The height direction (thickness direction) is the Z-axis direction. The direction opposite to the side (attachment side) on which the biological sensor is attached to the living body (subject) is the + Z axis direction, and the side (attachment side) to which the biological sensor is attached to the living body (subject) is the −Z axis direction. In the following description, for convenience of explanation, the + Z-axis direction side is referred to as an upper side or an upper side, and the −Z axis direction side is referred to as a lower side or a lower side, but does not represent a universal hierarchical relationship.

In examining the biosensor including the foamed sheet 20 and the electrode 30, the inventor of the present application considers the breaking elongation rate of the foamed base material 211 included in the foamed sheet 20 and the static friction coefficient μ of the electrode 30 to be the biosensor 1. We focused on the suppression of noise generated in the electrocardiogram, the improvement of the durability of the biological sensor 1, and the suppression of the burden on the skin 2 such as the covering of the skin. Then, the inventor of the present application states that when the breaking elongation rate of the foamed base material 211 is 30% to 500% and the static friction coefficient μ of the electrode 30 is 3.0 to 7.0, the biosensor 1 is the skin 2. It was discovered that it is possible to suppress the occurrence of misalignment on the sticking surface of. Therefore, it has been found that the biological sensor 1 can suppress noise generated in the electrocardiogram even when the subject is exercising such as walking or moving, and can stably acquire the waveform of the electrocardiogram (electrocardiogram waveform). At the same time, the inventor of the present application enhances the durability of the biosensor 1 and imparts it to the biosensor 1 skin 2 by setting the breaking elongation rate of the foamed base material 211 and the static friction coefficient μ of the electrode 30 within the above ranges. We found that the burden could be reduced.

[Case]
As shown in FIGS. 1 to 3, the housing 10 is located on the outermost side (+ Z-axis direction) of the biosensor 1 and is adhered to the upper surface of the foam sheet 20. The housing 10 has a projecting portion 11 projecting substantially on the dome in the height direction (+ Z axis direction) of FIG. 1 at the central portion in the longitudinal direction (Y-axis direction), and the inside of the projecting portion 11 ( On the sticking side), a recess 11a formed in a concave shape is formed on the living body side. Further, the lower surface (the surface on the sticking side) of the housing 10 is formed flat. On the inside (pasting side) of the protruding portion 11, a storage space S for accommodating the sensor portion 50 is formed by the recess 11a on the inner surface of the protruding portion 11 and the hole portion 211a of the foamed base material 211.

As the material for forming the housing 10, for example, a flexible material such as silicone rubber, fluororubber, or urethane rubber can be used. Further, the housing 10 can be formed by laminating the above-mentioned flexible material on the surface of the support using a base resin such as polyethylene terephthalate (PET) as the support. By forming the housing 10 using the above-mentioned flexible material or the like, the sensor unit 50 arranged in the storage space S of the housing 10 is protected, and the impact applied to the biological sensor 1 from the upper surface side is applied. It can absorb and soften the impact applied to the sensor unit 50.

The thickness of the upper surface and the side wall of the protruding portion 11 of the housing 10 is thicker than the thickness of the flat portions 12a and 12b provided on both ends in the longitudinal direction (Y-axis direction) of the housing 10. As a result, the flexibility of the protruding portion 11 can be made lower than the flexibility of the flat portions 12a and 12b, and the sensor portion 50 can be protected from the external force applied to the biological sensor 1.

The thickness of the upper surface and the side wall of the protruding portion 11 is preferably 1.5 mm to 3 mm, and the thickness of the flat portions 12a and 12b is preferably 0.5 mm to 1 mm.

Since the thin flat portions 12a and 12b have higher flexibility than the protruding portions 11, when the biosensor 1 is attached to the skin 2, the surface of the skin 2 due to body movements such as stretching, bending, and twisting It can be easily deformed by following the deformation. As a result, when the surface of the skin 2 is deformed, the stress applied to the flat portions 12a and 12b can be relaxed, and the biosensor 1 can be made difficult to peel off from the skin 2.

The outer peripheral portions of the flat portions 12a and 12b have a shape in which the thickness gradually decreases toward the ends. As a result, the flexibility of the outer peripheral portions of the flat portions 12a and 12b can be further increased, and the biosensor 1 is attached to the skin 2 as compared with the case where the thickness of the outer peripheral portions of the flat portions 12a and 12b is not reduced. It is possible to improve the wearing feeling when the skin is worn.

The hardness (strength) of the housing 10 is preferably 40 to 70, more preferably 50 to 60. When the hardness of the housing 10 is within the above-mentioned preferable range, when the skin 2 is stretched due to body movement, the foamed sheet 20 can be deformed according to the movement of the skin 2 without being affected by the housing 10. The hardness (hardness) refers to Shore A hardness.

[Foam sheet]
As shown in FIG. 3, the foam sheet 20 is provided so as to be adhered to the lower surface of the housing 10. The foam sheet 20 has a through hole 20a at a position facing the protrusion 11 of the housing 10. The sensor body 52 of the sensor unit 50 is housed in the storage space S formed by the recess 11a on the inner surface of the housing 10 and the through hole 20a without being blocked by the foam sheet 20 by the through hole 20a.

The foam sheet 20 has a foam sticking layer 21 and a housing adhesive layer 22 provided on the surface on the housing 10 side (+ Z axis direction).

(Foam sticking layer)
As shown in FIG. 3, the foamed pasting layer 21 includes a foamed base material (also referred to as a foam) 211 and an adhesive layer 212 for a base material provided on the surface of the foamed base material 211 on the living body side (-Z axis direction). And have.

((Foam base material))
The foamed base material 211 has a porous structure and can be formed by using a porous body having flexibility, waterproofness and moisture permeability. As the porous body, for example, a foam material such as open cells, closed cells, and semi-closed cells can be used. As a result, water vapor due to sweat or the like generated from the skin 2 to which the biosensor 1 is attached can be released to the outside of the biosensor 1 via the foamed base material 211.

The elongation at break of the foamed base material 211 is 30% to 500%, preferably 40% to 400%, and more preferably 50% to 300%. If the breaking elongation rate of the foamed base material 211 is less than 30%, the biosensor cannot follow the movement of the skin 2, the noise generated in the electrocardiogram waveform becomes large, and the subject tends to be uncomfortable. When the breaking elongation rate of the foamed base material 211 exceeds 500%, the volume of the voids formed inside the foamed base material 211 is large and the foamed base material 211 becomes too soft, so that the shape of the foamed base material 211 is unstable. become. Further, since liquids such as water and sweat easily infiltrate into the voids in the foamed base material 211 and the gaps between the foamed base material 211 and the base material adhesive layer 212 or the housing adhesive layer 22, the foamed base material 211 Durability tends to decrease. When the breaking elongation rate of the foamed base material 211 is 30% to 500%, the biosensor 1 tends to extend in contact with the skin 2 and can maintain the state of contact with the skin 2, so that noise generated in the electrocardiogram waveform is generated. Can be reduced and the discomfort given to the subject can be reduced. Further, since the liquid can be suppressed from entering the voids in the foamed base material 211 and the gap between the foamed base material 211 and the adhesive layer 212 for the base material or the adhesive layer 22 for the housing, the foamed base material 211 has durability. Can be maintained.

As shown in the following formula (1), the breaking elongation ratio of the foamed base material 211 is the length of the foamed base material 211 in the major axis direction or the minor axis direction at the time of breaking, before the foamed base material 211 is pulled. The ratio to the length in the axial direction or the minor axis direction.
Fracture elongation of the foamed base material 211 = length in the major axis direction or minor axis direction at the time of fracture of the foamed substrate 211 / length in the major axis direction or minor axis direction before pulling the foamed substrate 211 ... ( 1)

The elongation at break of the foamed base material 211 can be measured using a tensile tester (AGS-J, manufactured by Shimadzu Corporation). The tensile test conditions at this time can be appropriately set. For example, the width of the foamed base material 211 (the maximum width in the minor axis direction of the foamed base material 211) is 10 mm, and a pair of jigs for gripping both ends of the foamed base material 211. The initial distance between them is 50 mm, and the tensile strength is 300 mm / min. The breaking elongation of the foamed base material 211 may be any of the breaking elongation of the foamed base material 211 in the major axis direction and the minor axis direction, but from the viewpoint of ease of measurement, the breaking elongation ratio of the foamed base material 211 is in the major axis direction. The elongation at break is preferable. For the measurement of the elongation at break of the foamed base material 211, a rectangular sheet having a predetermined size (for example, short side 10 mm × long side 70 mm × thickness 0.5 mm) may be used for the foamed base material 211. When pulling the rectangular sheet, grasp and fix both ends of the rectangular sheet on the short side with a tensile test jig so that one or both of the pair of jigs has a tensile strength of 300 mm / min. You may move it to and pull the rectangular sheet. Both ends on the short side of the rectangular sheet refer to a region within a predetermined range (for example, 15 mm or less) from the surface on the short side, although it depends on the size of the rectangular sheet.

The elongation at break of the foamed base material 211 may be the average value of the measured values of the plurality of (for example, three) foamed base materials 211.

In the present embodiment, the outer shape of the foamed base material 211 is elliptical, and when the foamed base material 211 is attached to the skin 2, the foamed base material 211 is most easily expanded and contracted in the long axis direction. , It is preferable that the elongation at break in the major axis direction of the foamed base material 211. Even when the outer shape of the foamed base material 211 is rectangular, the breaking elongation rate of the foaming base material 211 is preferably the breaking elongation rate in the long side direction of the foamed base material 211. When the outer shape of the foamed base material 211 is square, the breaking elongation rate of the foaming base material 211 may be the breaking elongation ratio in one side direction of the foamed base material 211. When the outer shape of the foamed base material 211 is circular, the breaking elongation of the foamed base material 211 may be the breaking elongation of the diameter of the foamed base material 211.

As the material for forming the foamed base material 211, for example, a thermoplastic resin such as a polyurethane resin, a polystyrene resin, a polyolefin resin, a silicone resin, an acrylic resin, a vinyl chloride resin, or a polyester resin can be used. can.

The thickness of the foamed base material 211 can be appropriately set, and can be, for example, 0.5 mm to 1.5 mm.

The foam base material 211 has a hole 211a at a position facing the protrusion 11 of the housing 10. By forming the adhesive layer 212 for the substrate and the adhesive layer 22 for the housing on the surface of the foamed substrate 211 other than the holes 211a, the through holes 20a can be formed.

The foamed pasting layer 21 uses a foamed base material 211, but is not limited to this, and a base material having no porous structure may be used. The base material may have a breaking elongation rate of 30% to 500%, and may have flexibility, waterproofness, and moisture permeability. If the base material has a breaking elongation rate of 30% to 500% and has flexibility, waterproofness, and moisture permeability, it can easily extend in contact with the skin 2 and can maintain the state of contact with the skin 2. , The intrusion of the liquid into the gap between the foamed base material 211 and the base material adhesive layer 212 or the housing adhesive layer 22 can be suppressed, and the durability can be maintained. As a result, the water vapor generated from the skin 2 to which the biosensor 1 is attached can be released to the outside of the biosensor 1 via the base material.

As the material of the base material, as in the case of the foamed base material 211, for example, a thermoplastic resin such as a polyurethane resin, a polystyrene resin, a polyolefin resin, a silicone resin, an acrylic resin, a vinyl chloride resin, or a polyester resin can be used. Can be used.

((Adhesive layer for base material))
As shown in FIG. 3, the adhesive layer 212 for a base material is provided by being attached to the lower surface of the foamed base material 211, and adheres the foamed base material 211 and the base material 41, and also adheres the foamed base material 211 and the electrode 30. Has the function of adhering to.

The adhesive layer 212 for a base material preferably has moisture permeability. Water vapor or the like generated from the skin 2 to which the biosensor 1 is attached can be released to the foamed base material 211 via the adhesive layer 212 for the base material. Further, since the foamed base material 211 has a bubble structure as described above, water vapor can be discharged to the outside of the biological sensor 1 via the adhesive layer 22 for the housing. As a result, it is possible to prevent sweat or water vapor from accumulating at the interface between the skin 2 to which the biosensor 1 is attached and the adhesive layer 42 for sticking. As a result, the adhesive force of the base material adhesive layer 212 is weakened by the moisture accumulated at the interface between the skin 2 and the base material adhesive layer 212, and the biosensor 1 can be prevented from peeling off from the skin 2.

The moisture permeability of the adhesive layer 212 for the base material is preferably 1 (g / m ² · day) or more, and more preferably 10 (g / m ² · day) or more. The moisture permeability of the adhesive layer 212 for the base material is 10,000 (g / m ² · day) or less. When the moisture permeability of the adhesive layer 212 for the base material is 10 (g / m ² · day) or more, when the adhesive layer 42 for attachment is attached to the skin 2, sweat or the like transmitted from the adhesive sheet 40 for support is absorbed. Since it can be permeated to the outside, the load on the skin 2 can be suppressed.

The material for forming the pressure-sensitive adhesive layer 212 for the base material is preferably a material having pressure-sensitive adhesiveness, and the same material as the pressure-sensitive adhesive layer 42 for sticking can be used, and an acrylic pressure-sensitive adhesive is used. Is preferable.

As the adhesive layer 212 for the base material, a double-sided adhesive tape formed of the above material can be used. When the housing 10 is laminated on the adhesive layer 212 for a base material to form the biosensor 1, the waterproof property of the biosensor 1 can be improved and the bonding strength with the housing 10 can be improved.

The adhesive layer 212 for a base material has a wavy pattern (web pattern) formed on the surface thereof, in which an adhesive forming portion in which an adhesive is present and an adhered portion without an adhesive are alternately formed. You may. As the adhesive layer 212 for the base material, for example, a double-sided adhesive tape having a web pattern formed on its surface can be used. By having a web pattern on the surface of the adhesive layer 212 for a base material, it is possible to prevent the adhesive from adhering to the convex portion of the surface and its periphery, and to prevent the adhesive from adhering to the concave portion of the surface and its periphery. .. Therefore, since both the portion where the adhesive is present and the portion where the adhesive is not present are present on the surface of the adhesive layer 212 for the base material, the adhesive is scattered on the surface of the adhesive layer 212 for the base material. be able to. The moisture permeability of the adhesive layer 212 for a base material tends to increase as the adhesive is thinner. Therefore, the adhesive layer 212 for a base material has a web pattern formed on its surface, and the adhesive has a partially thin portion, so that the adhesive strength is maintained as compared with the case where the web pattern is not formed. However, the moisture permeability can be improved.

The width between the pressure-sensitive adhesive forming portion and the adhered portion can be appropriately designed, and the width of the pressure-sensitive adhesive forming portion is preferably, for example, 500 μm to 1000 μm, and the width of the adhered portion is 1500 μm to 5000 μm. Is preferable. When the widths of the pressure-sensitive adhesive forming portion and the portion to be adhered are within the above-mentioned preferable ranges, the pressure-sensitive adhesive layer 212 for a base material can exhibit excellent moisture permeability while maintaining the adhesive strength.

The thickness of the adhesive layer 212 for a base material can be appropriately set arbitrarily, and is preferably 10 μm to 300 μm, more preferably 50 μm to 200 μm, and even more preferably 70 μm to 110 μm. When the thickness of the adhesive layer 212 for the base material is 10 μm to 300 μm, the biosensor 1 can be made thinner.

(Adhesive layer for housing)
As shown in FIG. 3, the adhesive layer 22 for a housing is provided in a state of being attached to the upper surface of the foamed base material 211. The adhesive layer 22 for the housing is attached to the upper surface of the foamed base material 211 at a position corresponding to the flat surface on the attachment side (-Y-axis direction) of the housing 10, and the foamed base material 211 and the housing are attached. It has a function of adhering to 10.

As a material for forming the adhesive layer 22 for the housing, a silicon-based adhesive silicon tape or the like can be used.

The thickness of the adhesive layer 22 for the housing can be appropriately set, and can be, for example, 10 μm to 300 μm.

(electrode)
As shown in FIG. 3, the electrode 30 is connected to the lower surface of the adhesive layer 212 for the base material on the sticking side (-Z axis direction), and a part of the sensor body 52 side of the electrode 30 is connected to the wirings 53a and 53b. , It is attached in a state of being sandwiched between the adhesive layer 212 for a base material and the adhesive layer 43 for a sensor. The portion of the electrode 30 that is not sandwiched between the adhesive layer 212 for the base material and the adhesive layer 43 for the sensor comes into contact with the living body. When the biological sensor 1 is attached to the skin 2, the electrode 30 comes into contact with the skin 2, so that a biological signal can be detected. The biological signal is, for example, an electric signal representing an electrocardiogram waveform, an electroencephalogram, a pulse, or the like. The electrode 30 may be embedded in the base material 41 in a state of being exposed so as to be in contact with the skin 2.

The electrode 30 contains a conductive polymer and a binder resin, and the conductive polymer is contained in a state of being dispersed in the binder resin.

The electrode 30 can be formed by using an electrode sheet formed in the form of a cured product, metal, alloy or the like of a conductive composition containing a conductive polymer and a binder resin.

Examples of the conductive polymer include polythiophene-based conductive polymer, polyaniline-based conductive polymer, polypyrrole-based conductive polymer, polyacetylene-based conductive polymer, polyphenylene-based conductive polymer and derivatives thereof, and these. Complexes and the like can be used. These may be used alone or in combination of two or more.

Examples of the polythiophene-based conductive polymer include polythiophene, poly (3-methylthiophene), poly (3-ethylthiophene), poly (3-propylthiophene), poly (3-butylthiophene), and poly (3-hexylthiophene). , Poly (3-heptylthiophene), Poly (3-octylthiophene), Poly (3-decylthiophene), Poly (3-dodecylthiophene), Poly (3-octadecylthiophene), Poly (3-bromothiophene), Poly (3-chlorothiophene), poly (3-iodothiophene), poly (3-cyanothiophene), poly (3-phenylthiophene), poly (3,4-dimethylthiophene), poly (3,4-dibutylthiophene) , Poly (3-hydroxythiophene), Poly (3-methoxythiophene), Poly (3-ethoxythiophene), Poly (3-butoxythiophene), Poly (3-hexyloxythiophene), Poly (3-Heptyloxythiophene) , Poly (3-octyloxythiophene), Poly (3-decyloxythiophene), Poly (3-dodecyloxythiophene), Poly (3-octadecyloxythiophene), Poly (3,4-dihydroxythiophene), Poly (3) , 4-dimethoxythiophene), poly (3,4-diethoxythiophene), poly (3,4-dipropoxythiophene), poly (3,4-dibutoxythiophene), poly (3,4-dihexyloxythiophene) , Poly (3,4-diheptyloxythiophene), Poly (3,4-dioctyloxythiophene), Poly (3,4-didecyloxythiophene), Poly (3,4-didodecyloxythiophene), Poly (3,4-didodecyloxythiophene) 3,4-ethylenedioxythiophene) (also called PEDOT), poly (3,4-propylenedioxythiophene), poly (3,4-butendioxythiophene), poly (3-methyl-4-methoxythiophene) , Poly (3-methyl-4-ethoxythiophene), Poly (3-carboxythiophene), Poly (3-methyl-4-carboxythiophene), Poly (3-methyl-4-carboxyethylthiophene), Poly (3- Methyl-4-carboxybutylthiophene) and the like.

Examples of the polyaniline-based conductive polymer include polyaniline, polystyrene sulfonic acid (also referred to as PSS), polyvinyl sulfonic acid, polyallyl sulfonic acid, polyacrylic sulfonic acid, polymethacrylic sulfonic acid, and poly (2-acrylamide-2-methylpropanesulfonic acid). Polymers with sulfonic acid groups such as acid), polyisoprenesulfonic acid, polysulfoethylmethacrylate, poly (4-sulfobutylmethacrylate), polymethacryloxybenzenesulfonic acid, polyvinylcarboxylic acid, polystyrenecarboxylic acid, polyallylcarboxylic acid. Examples thereof include polymers having a carboxylic acid group such as acid, polyacrylic carboxylic acid, polymethacrylic carboxylic acid, poly (2-acrylamide-2-methylpropane carboxylic acid), polyisoprene carboxylic acid, and polyacrylic acid. These may be used as a homopolymer obtained by polymerizing one kind alone, or may be used as a copolymer of two or more kinds. Among these polyanions, a polymer having a sulfonic acid group is preferable, and polystyrene sulfonic acid is more preferable, because the conductivity can be made higher.

Polypyrrole-based conductive polymers include polypyrrole, poly (N-methylpyrrole), poly (3-methylpyrrole), poly (3-ethylpyrrole), poly (3-n-propylpyrrole), and poly (3-butyl). Pyrrole), poly (3-octylpyrrole), poly (3-decylpyrrole), poly (3-dodecylpyrrole), poly (3,4-dimethylpyrrole), poly (3,4-dibutylpyrrole), poly (3) -Carboxypyrrole), Poly (3-Methyl-4-carboxypyrrole), Poly (3-Methyl-4-carboxyethylpyrrole), Poly (3-Methyl-4-carboxybutylpyrrole), Poly (3-Hydroxypyrrole) , Poly (3-methoxypyrrole), poly (3-ethoxypyrrole), poly (3-butoxypyrrole), poly (3-hexyloxypyrrole), poly (3-methyl-4-hexyloxypyrrole) and the like. ..

Examples of the polyacetylene-based conductive polymer include polyacetylene monoester having an ester at the para-position of phenylacetylene and polyacetylene having a polar group such as polyphenylacetylene monoamide having an amide at the para-position of phenylacetylene.

Examples of the polyphenylene-based conductive polymer include polyphenylene vinylene and the like.

Examples of these complexes include a complex obtained by doping polythiophene with polyaniline as a dopant. As a complex of polythiophene and polyaniline, PEDOT / PSS or the like obtained by doping PEDOT with PSS can be used.

Among the above, as the conductive polymer, a composite obtained by doping polythiophene with polyaniline as a dopant is preferable. Among the complexes of polythiophene and polyaniline, PEDOT / PSS obtained by doping PEDOT with PSS is more preferable because it has a lower contact impedance with a living body and has high conductivity.

Further, the electrode 30 preferably has a plurality of through holes 31 on the contact surface with the skin 2. As a result, the electrode 30 can be exposed to the sticking side from the through hole 31 in a state of being stuck to the base material adhesive layer 212, so that the electrode 30 and the skin 2 are in close contact with each other. You can improve your sex.

The coefficient of static friction μ of the electrode 30 is 3.0 to 7.0, preferably 3.5 to 6.5, and more preferably 4.0 to 6.0. When the static friction coefficient μ of the electrode 30 is less than 3.0, the tack of the electrode 30 becomes small, so that the electrode 30 is easily displaced from the skin 2. Therefore, the noise generated in the electrocardiogram waveform measured by the biosensor 1 tends to increase. When the static friction coefficient μ of the electrode 30 exceeds 7.0, the electrode 30 sticks to the skin 2 too strongly. Therefore, when the biosensor 1 is attached to the skin 2 for a long time (for example, 24 hours), the skin 2 The burden on the skin 2 such as rough skin tends to increase. When the static friction coefficient μ of the electrode 30 is within the above-mentioned preferable range, the electrode 30 can have an appropriate tack, so that the adhesiveness to the skin 2 can be maintained. Therefore, the electrode 30 can be made difficult to be displaced from the skin 2. Further, since the electrode 30 can be appropriately attached to the skin 2 with an adhesive force, the burden on the skin 2 can be reduced.

The coefficient of static friction μ is the ratio of the maximum frictional force acting on the contact surface and the magnitude of the drag force perpendicular to the contact surface when the two objects are in contact with each other and are stationary.

In the present embodiment, the static friction coefficient μ of the electrode 30 can be measured by using a static friction coefficient measuring machine (Tribogear TYPE: 10 manufactured by Shinto Kagaku Co., Ltd.). The coefficient of static friction μ of the electrode 30 with respect to the simulated skin can be measured as follows. For the pseudo-skin, a bio-skin plate (manufactured by Viewlac Co., Ltd., product number P001-001, length 195 mm x width) that reproduces the surface wrinkles and the affinity hydrophobicity similar to that of dry human skin by processing the surface of the urethane elastomer film. 120 mm × thickness 5 mm) or the like may be used. Then, the bioskin plate is fixed to the rising plate in a horizontal state, the electrode 30 is attached to a flat indenter having a predetermined size (for example, length 75 mm × width 35 mm), and the load is 1.47 N for 30 seconds. After standing still, it is tilted at an average ascending speed of 10 degrees / 6 seconds, and the friction angle θd when the planar indenter starts to slide is read. By applying this read friction angle θd to the following equation (I), the static friction coefficient μ can be obtained.
Static friction coefficient μ = tan (θd × π / 180) ・ ・ ・ (I)

[Adhesive sheet for support]
As shown in FIG. 3, the supporting pressure-sensitive adhesive sheet 40 has a base material 41, a sticking pressure-sensitive adhesive layer 42, and a sensor pressure-sensitive adhesive layer 43.

(Second base material)
As shown in FIG. 3, the base material 41 has the outer shapes on both sides of the adhesive layer 42 for sticking in the width direction (X-axis direction) on both sides of the housing 10 and the foam sheet 20 in the width direction (X-axis direction). It is almost the same as the outer shape. The length of the base material 41 (Y-axis direction) is shorter than the length of the housing 10 and the foam sheet 20 (Y-axis direction). Both ends of the support adhesive sheet 40 in the longitudinal direction are positions where the wirings 53a and 53b of the sensor unit 50 are sandwiched between the support adhesive sheet 40 and the foam sheet 20, and are located at positions where they overlap with a part of the electrode 30. .. The sensor adhesive layer 43 is provided on the upper surface of the base material 41, and the base material adhesive layer 212 is provided on the sticking surface of the foamed sheet 20. The adhesive layer 43 for the sensor of the supporting adhesive sheet 40 and the adhesive layer 212 for the base material of the foamed sheet 20 protruding from both ends in the longitudinal direction of the supporting adhesive sheet 40 form a surface to be attached to the skin 2. .. As a result, the waterproofness and moisture permeability differ depending on the position of the sticking surface, and the adhesiveness also differs. However, in the whole biosensor 1, the adhesiveness on the sticking surface corresponding to the foam sheet 20 is the skin. It will greatly affect the sticking performance to 2.

The base material 41 can be formed by using a flexible resin having appropriate elasticity, flexibility and toughness. Examples of the material forming the base material 41 include polyester resins such as polyethylene terephthalate (PET), polybutylene terephthalate, polytrimethylene terephthalate, polyethylene naphthalate, and polybutylene naphthalate; polyacrylic. Acrylic resins such as acid, polymethacrylic acid, methyl polyacrylate, polymethylmethacrylate (PMMA), ethyl polymethacrylate, butyl polyacrylate; polyolefin resins such as polyethylene and polypropylene; polystyrene, imide-modified polystyrene, acrylonitrile Polyethylene resin such as butadiene / styrene (ABS) resin, imide-modified ABS resin, styrene / acrylonitrile copolymer (SAN) resin, acrylonitrile / ethylene-propylene-diene / styrene (AES) resin; polyimide resin; polyurethane resin Acrylic resin; A thermoplastic resin such as a polyvinyl chloride resin such as a polyvinyl chloride or a vinyl chloride-vinyl acetate copolymer resin can be used. Among these, polyolefin-based resins and PET are preferably used. These thermoplastic resins are waterproof (low moisture permeability). Therefore, the base material 41 is formed by using these thermoplastic resins, so that the sweat or water vapor generated from the skin 2 causes the base material 41 in a state where the biological sensor 1 is attached to the skin 2 of the living body. It is possible to prevent the sensor unit 50 from invading the flexible substrate 51 side through the sensor unit 50.

Since the sensor portion 50 is installed on the upper surface of the base material 41, it is preferable that the base material 41 is formed in a flat plate shape.

The thickness of the base material 41 can be arbitrarily selected, for example, preferably 1 μm to 300 μm, more preferably 5 μm to 100 μm, and further preferably 10 μm to 50 μm.

(Adhesive layer for sticking)
As shown in FIG. 3, the sticking adhesive layer 42 is provided on the lower surface of the base material 41 on the sticking side (−Z axis direction), and is a layer that comes into contact with a living body.

The adhesive layer 42 for sticking preferably has pressure-sensitive adhesiveness. Since the adhesive layer 42 for attachment has pressure-sensitive adhesiveness, it can be easily attached to the skin 2 by pressing the biological sensor 1 against the skin 2 of the living body.

The material of the adhesive layer 42 for sticking is not particularly limited as long as it is a material having pressure-sensitive adhesiveness, and examples thereof include materials having biocompatibility. Examples of the material for forming the adhesive layer 42 for sticking include an acrylic pressure-sensitive adhesive and a silicone-based pressure-sensitive adhesive. Acrylic pressure-sensitive adhesives are preferable.

The acrylic pressure-sensitive adhesive preferably contains an acrylic polymer as a main component. The acrylic polymer can function as a pressure sensitive adhesive component. The acrylic polymer contains a (meth) acrylic acid ester such as isononyl acrylate and methoxyethyl acrylate as a main component, and a monomer component containing a monomer copolymerizable with a (meth) acrylic acid ester such as acrylic acid as an optional component. A polymer obtained by polymerizing the above can be used.

The acrylic pressure-sensitive adhesive preferably further contains a carboxylic acid ester. The carboxylic acid ester functions as a pressure-sensitive adhesive force adjusting agent that reduces the pressure-sensitive adhesive force of the acrylic polymer and adjusts the pressure-sensitive adhesive force of the adhesive layer 42 for sticking. As the carboxylic acid ester, a carboxylic acid ester compatible with the acrylic polymer can be used. As the carboxylic acid ester, trifatty acid glyceryl and the like can be used.

The acrylic pressure-sensitive adhesive may contain a cross-linking agent, if necessary. The cross-linking agent is a cross-linking component that cross-links the acrylic polymer. Examples of the cross-linking agent include polyisocyanate compounds (polyfunctional isocyanate compounds), epoxy compounds, melamine compounds, peroxide compounds, urea compounds, metal alkoxide compounds, metal chelate compounds, metal salt compounds, carbodiimide compounds, oxazoline compounds, aziridine compounds, and amines. Examples include compounds. Among these, a polyisocyanate compound is preferable. These cross-linking agents may be used alone or in combination.

The adhesive layer 42 for sticking preferably has excellent biocompatibility. For example, when the adhesive layer 42 for application is subjected to a keratin peeling test, the keratin peeling area ratio is preferably 0% to 50%, more preferably 1% to 15%. When the keratin peeling area ratio is in the range of 0% to 50%, the load on the skin 2 can be suppressed even if the adhesive layer 42 for sticking is attached to the skin 2.

The adhesive layer 42 for sticking preferably has moisture permeability. Water vapor or the like generated from the skin 2 to which the biosensor 1 is attached can be released to the foam sheet 20 side via the adhesive layer 42 for attachment. Further, since the foamed sheet 20 has a bubble structure as described later, water vapor can be discharged to the outside of the biological sensor 1 via the adhesive layer 42 for sticking. As a result, it is possible to prevent sweat or water vapor from accumulating at the interface between the skin 2 to which the biosensor 1 is attached and the adhesive layer 42 for sticking. As a result, the adhesive force of the adhesive layer 42 for attachment is weakened by the moisture accumulated at the interface between the skin 2 and the adhesive layer 42 for attachment, and it is possible to prevent the biological sensor 1 from peeling off from the skin.

The moisture permeability of the adhesive layer 42 for sticking is preferably 300 (g / m ² · day) or more, more preferably 600 (g / m ² · day) or more, and 1000 (g / m ² · day) or more. Day) or more is more preferable. The moisture permeability of the adhesive layer 42 for sticking is 10,000 (g / m ² · day) or less. If the moisture permeability of the adhesive layer 42 for application is 300 (g / m ² · day) or more, even if the adhesive layer 42 for application is attached to the skin 2, sweat or the like generated from the skin 2 is appropriately used as a base material. Since it can be permeated from 41 to the outside, the burden on the skin 2 can be reduced.

The thickness of the adhesive layer 42 for sticking can be arbitrarily selected, and is preferably 10 μm to 300 μm. When the thickness of the adhesive layer 42 for sticking is 10 μm to 300 μm, the biosensor 1 can be made thinner.

(Adhesive layer for sensor)
As shown in FIG. 4, the sensor adhesive layer 43 is provided on the upper surface of the base material 41 on the housing 10 side (+ Z axis direction), and is a layer to which the sensor portion 50 is adhered. Since the same material as the adhesive layer 42 for sticking can be used for the adhesive layer 43 for the sensor, the details will be omitted. The sensor adhesive layer 43 does not necessarily have to be provided, and an adhesive may be provided on a part or all of the base material 41 instead of the sensor adhesive layer 43.

(Sensor part)
FIG. 4 is a plan view showing the configuration of the sensor unit 50, and FIG. 5 is an exploded perspective view of a part of the sensor unit 50. The broken line in FIG. 4 indicates the outer diameter of the housing 10. As shown in FIGS. 4 and 5, the sensor unit 50 includes a flexible substrate 51 on which various components for acquiring biometric information are mounted, a sensor main body 52, and wiring 53a connected to the sensor main body 52 in the longitudinal direction thereof. And 53b, a battery 54, a positive electrode pattern 55, a negative electrode pattern 56, and a conductive adhesive tape 57. Between the pad portion 522a and the pad portion 522b of the sensor portion 50, a positive electrode pattern 55, a conductive adhesive tape 57, a battery 54, a conductive adhesive tape 57 and a negative electrode pattern 56 are arranged in this order from the pad portion 522a side. It is laminated over the pad portion 522b side. In the present embodiment, the positive electrode terminal of the battery 54 is in the −Z axis direction and the negative electrode terminal is in the + Z axis direction, but the opposite may be true, and the positive electrode terminal may be in the + Z axis direction and the negative electrode terminal may be in the −Z axis direction. good.

The flexible substrate 51 is a resin substrate, and the sensor main body 52 and the wirings 53a and 53b are integrally formed on the flexible substrate 51.

One ends of the wirings 53a and 53b are connected to the electrodes 30, respectively, as shown in FIG. As shown in FIG. 4, the other end of the wiring 53a is connected to a switch or the like mounted on the component mounting portion 521 along the outer circumference of the sensor main body 52. The other end of the wiring 53b is also connected to a switch or the like mounted on the component mounting portion 521, similarly to the wiring 53a. The wirings 53a and 53b may be formed on either the front surface side or the back surface side wiring layer of the flexible substrate 51.

As shown in FIG. 4, the sensor main body 52 has a component mounting unit 521 which is a control unit and a battery mounting unit 522.

The component mounting unit 521 is a flexible substrate 51 such as a CPU and an integrated circuit that processes a biometric signal acquired from a living body to generate biometric signal data, a switch for activating the biometric sensor 1, a flash memory for storing the biometric signal, a light emitting element, and the like. Has various parts to be mounted on. Circuit examples using various parts will be omitted. The component mounting unit 521 operates by the electric power supplied from the battery 54 mounted on the battery mounting unit 522.

The component mounting unit 521 transmits to an external device such as an operation confirmation device for confirming the initial operation and a reading device for reading biometric information from the biosensor 1 by wire or wirelessly.

The battery mounting unit 522 supplies electric power to an integrated circuit or the like mounted on the component mounting unit 521. As shown in FIG. 2, the battery 54 is mounted on the battery mounting portion 522.

As shown in FIG. 5, the battery mounting portion 522 is arranged between the wiring 53a and the component mounting portion 521, and has pad portions 522a and 522b and a constricted portion 522c.

As shown in FIG. 5, the pad portion 522a is provided between the wiring 53a and the component mounting portion 521, is located on the positive electrode terminal side of the battery 54, and has a positive electrode pattern 55 to which the positive electrode terminal is connected. There is.

As shown in FIG. 5, the pad portion 522b is provided in the direction orthogonal to the pad portion 522a in the longitudinal direction (upper direction in FIG. 3) at a predetermined distance from the pad portion 522a. The pad portion 522b is located on the negative electrode terminal (second terminal) side of the battery 54 and has a negative electrode pattern 56 to which the negative electrode terminal is connected.

As shown in FIG. 5, the constricted portion 522c is arranged between the pad portions 522a and 522b, and connects the pad portions 522a and 522b to each other.

As shown in FIG. 5, the battery 54 is arranged between the positive electrode pattern 55 and the negative electrode pattern 56. The battery 54 has a positive electrode terminal and a negative electrode terminal, and a known battery can be used. As the battery 54, for example, a coin-type battery such as CR2025 can be used.

As shown in FIG. 5, the positive electrode pattern 55 is located on the positive electrode terminal side of the battery 54 and is connected to the positive electrode terminal. The positive electrode pattern 55 has a rectangular shape with chamfered corners.

As shown in FIG. 5, the negative electrode pattern 56 is located on the negative electrode terminal side of the battery 54 and is connected to the negative electrode terminal. The negative electrode pattern 56 has a shape substantially corresponding to the size of the circular shape of the negative electrode terminal of the battery 54. The diameter of the negative electrode pattern 56 is, for example, equal to the diameter of the battery 54 and has a size substantially equal to the diagonal length of the positive electrode pattern 55.

The conductive adhesive tape 57 is a conductive adhesive, and is arranged between the battery 54 and the positive electrode pattern 55 and between the battery 54 and the negative electrode pattern 56, respectively. The conductive adhesive tape may also be generally referred to as a conductive adhesive sheet, a conductive adhesive film, or the like.

When the battery 54 is attached to the biosensor 1, the conductive adhesive tape 57A and the conductive adhesive tape 57B are attached to the entire positive electrode pattern 55 and the negative electrode pattern 56, respectively. Then, the positive electrode terminal and the negative electrode terminal of the battery 54 are attached to the positive electrode pattern 55 and the negative electrode pattern 56 via the conductive adhesive tape 57A and the conductive adhesive tape 57B, respectively, so that the battery 54 is attached to the battery mounting portion 522. It will be installed. The sensor body 52 shown in FIG. 4 has a state in which the constricted portion 522c is bent and the battery 54 is mounted on the battery mounting portion 522 with the battery 54 sandwiched between the positive electrode pattern 55 and the negative electrode pattern 56. Shows.

As shown in FIG. 3, the biosensor 1 is attached with a release paper 60 on the attachment surface side (-Z axis direction) until the biosensor 1 is attached to the skin 2 in order to protect the base material 41 and the electrode 30. It is preferable to attach it. By peeling the release paper 60 from the base material 41 and the electrode 30 at the time of use, the adhesive strength of the base material 41 can be maintained.

FIG. 6 is an explanatory diagram showing a state in which the biosensor 1 of FIG. 1 is attached to the chest of the living body P. For example, the biosensor 1 is attached to the skin of the subject P with the longitudinal direction (Y-axis direction) aligned with the sternum of the subject P, with one electrode 30 on the upper side and the other electrode 30 on the lower side. .. The biological sensor 1 is attached from the subject P to the skin of the subject P by the electrode 30 in a state where the electrode 30 is pressure-bonded to the skin of the subject P by being attached to the skin of the subject P by the adhesive layer 42 for attachment in FIG. Acquire biological signals such as electrocardiogram signals. The biological sensor 1 stores the acquired biological signal data in a non-volatile memory such as a flash memory mounted on the component mounting unit 521.

The method for manufacturing the biosensor 1 is not particularly limited, and the biosensor 1 can be manufactured by any method as appropriate. An example of the manufacturing method of the biological sensor 1 will be described.

The housing 10, the foam sheet 20, the electrodes 30, the supporting adhesive sheet 40, and the sensor unit 50 shown in FIG. 1 are prepared. The housing 10, the foamed sheet 20, and the supporting adhesive sheet 40 are not particularly limited as long as they can be manufactured, and can be manufactured by any manufacturing method as appropriate.

Similar to the housing 10, the foamed sheet 20, and the support adhesive sheet 40, the electrode 30 is not particularly limited as long as it can be manufactured by a method capable of manufacturing the electrode 30, and can be manufactured by any manufacturing method as appropriate. For example, the electrode 30 can be manufactured using a conductive composition.

The conductive composition will be described. The conductive composition contains a conductive polymer and a binder resin, and the conductive polymer is contained in a state of being dispersed in the binder resin.

Since the conductive polymer is the same as above, the details will be omitted.

The content of the conductive polymer is preferably 0.20 parts by mass to 20 parts by mass, and more preferably 2.5 parts by mass to 15 parts by mass with respect to 100 parts by mass of the conductive composition. , 3.0 parts by mass to 12 parts by mass, more preferably. The conductive composition can have excellent conductivity, toughness and flexibility as long as the content is within the above-mentioned preferable range with respect to the conductive composition.

The conductive polymer may be a solid material formed into pellets. In this case, a part of the solid material of the conductive polymer may be dissolved in the solvent within a range that does not cause a large change in the content of each component with respect to the conductive composition.

The conductive polymer may be used as an aqueous solution dissolved in a solvent. In this case, as the solvent, an organic solvent and an aqueous solvent can be used. Examples of the organic solvent include ketones such as acetone and methyl ethyl ketone (MEK); esters such as ethyl acetate; ethers such as propylene glycol monomethyl ether; and amides such as N, N-dimethylformamide. Examples of the aqueous solvent include water; alcohols such as methanol, ethanol, propanol and isopropanol. Among these, it is preferable to use an aqueous solvent.

As the binder resin, a water-soluble polymer, a water-insoluble polymer, or the like can be used. As the binder resin, it is preferable to use a water-soluble polymer from the viewpoint of compatibility with other components contained in the conductive composition. The water-soluble polymer may contain a polymer having hydrophilicity (hydrophilic polymer), which is not completely soluble in water.

As the water-soluble polymer, a hydroxyl group-containing polymer or the like can be used. As the hydroxyl group-containing polymer, saccharides such as agarose, polyvinyl alcohol (PVA), modified polyvinyl alcohol, polypyrrole, a copolymer of acrylic acid and sodium acrylate and the like can be used. These may be used alone or in combination of two or more. Among these, polyvinyl alcohol or modified polyvinyl alcohol is preferable, and modified polyvinyl alcohol is more preferable.

Examples of the modified polyvinyl alcohol include acetacetyl group-containing polyvinyl alcohol and diacetone acrylamide-modified polyvinyl alcohol. As the diacetone acrylamide-modified polyvinyl alcohol, for example, the diacetone acrylamide-modified polyvinyl alcohol-based resin (DA-modified PVA-based resin) described in JP-A-2016-166436 can be used.

Examples of polypyrrole include polyaniline and polyacetylene.

The content of the binder resin is preferably 5 parts by mass to 140 parts by mass, more preferably 10 parts by mass to 100 parts by mass, and 20 parts by mass to 70 parts by mass with respect to 100 parts by mass of the conductive composition. It is more preferably by mass. As long as the content is within the above-mentioned preferable range with respect to the conductive composition, the cured product obtained by using the conductive composition can have excellent conductivity, toughness and flexibility. ..

The binder resin may be used as an aqueous solution dissolved in a solvent. As the solvent, the same solvent as in the case of the above-mentioned conductive polymer can be used.

The conductive composition preferably further contains at least one of a cross-linking agent and a plasticizer. The cross-linking agent and the plasticizer have a function of imparting toughness and flexibility to the cured product obtained by using the conductive composition.

In addition, toughness is a property that achieves both excellent strength and elongation. The toughness does not include the property that one of the strength and the elongation is remarkably excellent, but the other is remarkably low, and includes the property that the balance of both the strength and the elongation is excellent.

Flexibility is a property that can suppress the occurrence of damage such as breakage in the bent portion after bending the cured product containing the conductive composition.

The cross-linking agent has a function of cross-linking the binder resin. By including the cross-linking agent in the binder resin, the toughness of the cured product obtained by using the conductive composition can be improved. The cross-linking agent preferably has reactivity with a hydroxyl group. If the cross-linking agent has reactivity with a hydroxyl group, the cross-linking agent can react with the hydroxyl group of the hydroxyl group-containing polymer when the binder resin is a hydroxyl group-containing polymer.

Examples of the cross-linking agent include zirconium compounds such as zirconium salts; titanium compounds such as titanium salts; boron compounds such as boric acid; isocyanate compounds such as blocked isocyanate; aldehyde compounds such as sodium glyoxylate, formaldehyde, acetaldehyde, glyoxal and glutaaldehyde; Examples thereof include an alkoxyl group-containing compound and a methylol group-containing compound. These may be used alone or in combination of two or more. Above all, when the binder resin is porvinyl alcohol, it easily reacts with porvinyl alcohol to form a crosslinked structure, and it is easy to maintain the performance of the cured product obtained by using the conductive composition. Sodium acid acid is preferred.

Since the cross-linking agent is an optional component, it does not necessarily have to be contained in the conductive composition, and the content of the cross-linking agent may be 0 parts by mass. When a cross-linking agent is contained, the content of the cross-linking agent is preferably 0.01 part by mass to 1.5 parts by mass, and 0.2 parts by mass to 1.2 parts by mass with respect to 100 parts by mass of the conductive composition. It is more preferably parts by mass, and more preferably 0.4 parts by mass to 1.0 part by mass. If the content is within the above-mentioned preferable range, the cured product obtained by using the conductive composition can have excellent toughness and flexibility.

The cross-linking agent may be used as an aqueous solution dissolved in a solvent. As the solvent, the same solvent as in the case of the above-mentioned conductive polymer can be used.

The plasticizer has a function of improving the conductivity of the cured product obtained by using the conductive composition and improving the tensile elongation and flexibility. Examples of the plasticizer include glycerin, ethylene glycol, propylene glycol, sorbitol, and polyol compounds such as N-methylpyrrolidone (NMP), dimethylformaldehyde (DMF), N-N'-dimethylacetamide (DMAc), and dimethyl sulfoxide. Examples thereof include aprotonic compounds such as (DMSO). These may be used alone or in combination of two or more. Among these, glycerin is preferable from the viewpoint of compatibility with other components.

The content of the plasticizer is preferably 0.2 parts by mass to 150 parts by mass, more preferably 1.0 part by mass to 90 parts by mass, with respect to 100 parts by mass of the conductive composition. It is more preferably parts by mass to 70 parts by mass. If the content is within the above-mentioned preferable range, the cured product obtained by using the conductive composition can have excellent toughness and flexibility.

Since the conductive composition contains at least one of a cross-linking agent and a plasticizer, the cured product obtained by using the conductive composition can improve toughness and flexibility.

When the conductive composition contains a cross-linking agent but no plasticizer, the cured product obtained by using the conductive composition can improve toughness, that is, both tensile strength and tensile elongation. , Flexibility can be improved.

When the conductive composition contains a plasticizer but does not contain a cross-linking agent, the tensile elongation of the cured product obtained by using the conductive composition can be improved. Therefore, the conductive composition is used as a whole. The obtained cured product can improve toughness. In addition, the flexibility of the cured product obtained by using the conductive composition can be improved.

The conductive composition preferably contains both a cross-linking agent and a plasticizer. When the conductive composition contains both a cross-linking agent and a plasticizer, the cured product obtained by using the conductive composition can have even better toughness.

In addition to the above components, the conductive composition may be filled with a surfactant, a softener, a stabilizer, a leveling agent, an antioxidant, an antioxidant, a leavening agent, a thickener, a colorant, and a filling agent, if necessary. Various known additives such as agents may be appropriately contained in an arbitrary ratio. Examples of the surfactant include silicone-based surfactants.

The conductive composition is prepared by mixing each of the above-mentioned components in the above-mentioned ratio.

The conductive composition may contain a solvent in an appropriate ratio, if necessary. As a result, an aqueous solution of the conductive composition (an aqueous solution of the conductive composition) is prepared.

As the solvent, an organic solvent or an aqueous solvent can be used. Examples of the organic solvent include ketones such as acetone and methyl ethyl ketone (MEK); esters such as ethyl acetate; ethers such as propylene glycol monomethyl ether; and amides such as N, N-dimethylformamide. Examples of the aqueous solvent include water; alcohols such as methanol, ethanol, propanol and isopropanol. Among these, it is preferable to use an aqueous solvent.

The cured product obtained by using the conductive composition preferably has a pH of 1 to 10, more preferably 1 to 8, and even more preferably 1 to 6. The pH of the cured product can be measured by any method as appropriate. For example, a method in which the litmus test paper is brought into contact with the cured product may be used, or a solution in which the conductive composition is dissolved in a solvent is brought into contact with the litmus test paper. A method or the like can be used.

An example of a method for manufacturing the electrode 30 using the conductive composition will be described.

By mixing the conductive polymer and the binder resin in the above ratio, a conductive composition containing the conductive polymer and the binder resin is produced. The conductive composition may further contain at least one of a cross-linking agent and a plasticizer in the above proportions. When preparing the conductive composition, the conductive polymer, the binder resin and the cross-linking agent may be used as an aqueous solution dissolved in a solvent.

The conductive composition contains, if necessary, a solvent containing a conductive polymer, a binder resin and a cross-linking agent in an appropriate ratio, and an aqueous solution of the conductive composition (aqueous solution of the conductive composition). ) May be used. As the solvent, the same solvent as the above solvent can be used.

After the conductive composition is applied to the surface of the release base material, the conductive composition is heated to promote the cross-linking reaction of the binder resin contained in the conductive composition and to cure the binder resin. As a result, a cured product of the conductive composition is obtained. The obtained cured product is cured by forming one or more through holes on the surface of the cured product by punching (pressing) the surface of the cured product using a press machine or the like, if necessary. The outer shape of the object is molded into a predetermined shape. As a result, a bioelectrode, that is, an electrode 30, which is a molded body having one or more through holes on the surface and having an outer shape having a predetermined shape, can be obtained. It should be noted that the molding may be performed by a laser processing machine instead of the press machine. Further, the obtained cured product may have only one or more through holes formed on its surface, or may have only its outer shape formed into a predetermined shape. Further, when the cured product can be used as a bioelectrode as it is, the cured product may be used as a bioelectrode without molding or the like.

Each component of the conductive polymer, the binder resin, the cross-linking agent, and the plasticizer contained in the electrode 30 has a content equivalent to the amount added at the time of producing the conductive composition.

As the peeling base material, a separator, a core material, or the like can be used. As the separator, a resin film such as a polyethylene terephthalate (PET) film, a polyethylene (PE) film, a polypropylene (PP) film, a polyamide (PA) film, a polyimide (PI) film, or a fluororesin film can be used. As the core material, a resin film such as PET film or PI film; a ceramic sheet; a metal film such as aluminum foil; a resin substrate reinforced with glass fiber or plastic non-woven fiber; a silicone substrate or a glass substrate should be used. Can be done.

As a method of applying the conductive composition on the peeling substrate, a roll coat, a screen coat, a gravure coat, a spin coat, a reverse coat, a bar coat, a blade coat, an air knife coat, a dipping method, a dispensing method, etc., and a small amount A method of hanging the conductive composition of the above on a substrate and stretching it with a doctor blade can be used. By these coating methods, the conductive composition is uniformly coated on the peeling substrate.

As a method for heating the conductive composition, known dryers such as a drying oven, a vacuum oven, an air circulation type oven, a hot air dryer, a far infrared dryer, a microwave vacuum dryer, and a high frequency dryer can be used. ..

The heating conditions may be any conditions as long as the cross-linking agent contained in the conductive composition can react.

The heating temperature of the conductive composition is a temperature at which curing of the binder resin contained in the conductive composition can proceed. The heating temperature is preferably 100 ° C to 200 ° C. When the conductive composition contains a cross-linking agent, if the heating temperature is in the range of 100 ° C. to 200 ° C., the reaction of the cross-linking agent is likely to proceed and the curing of the binder resin can be promoted.

The heating time of the conductive composition is preferably 0.5 minutes to 300 minutes, more preferably 5 minutes to 120 minutes. If the heating time is within the range of 0.5 minutes to 300 minutes, the binder resin can be sufficiently cured.

Then, after preparing the housing 10, the foam sheet 20, the electrode 30, the support adhesive sheet 40 and the sensor unit 50 constituting the biosensor 1 shown in FIG. 1, the sensor unit 50 is placed on the support adhesive sheet 40. Install. After that, the housing 10, the foamed sheet 20, the electrode 30, and the supporting adhesive sheet 40 are laminated in this order from the housing 10 side toward the supporting adhesive sheet 40 side. The release paper 60 may be attached to the sticking surface side of the foam sheet 20 and the supporting adhesive sheet 40 to the living body.

As a result, the biosensor 1 shown in FIG. 1 is obtained.

As described above, the biosensor 1 includes a housing 10, a foamed base material 211, and an electrode 30. Since the foamed base material 211 has a breaking elongation rate of 30% to 500%, the foamed pasting layer 21 has appropriate flexibility as a whole and can be flexibly deformed with respect to the contact surface with the skin 2. Therefore, when the biological sensor 1 is attached to the skin 2 and used, even if the skin 2 moves due to the body movement of the living body or the like, the foamed sheet 20 easily deforms following the movement of the skin 2 and comes into contact with the skin 2. Since it is easy to maintain the state, it is possible to suppress an increase in noise generated in the electrocardiogram. Further, since the electrode 30 has a static friction coefficient μ of 3.0 to 7.0, the adhesiveness to the skin 2 can be maintained. Therefore, the electrode 30 is less likely to be displaced from the surface to be attached to the skin 2, and can be suppressed from peeling from the skin 2, so that an increase in noise generated in the electrocardiogram can be suppressed. Therefore, the biological sensor 1 can stably acquire the electrocardiogram waveform even when the subject is exercising and moving.

In particular, in the biosensor 1 having the above configuration, the electrode 30 is provided on a part of the surface of the foamed base material 211 on the sticking side via the adhesive layer 212 for the base material, and the foamed base material 211 is substantially in the center thereof. The portion has a hole portion 211a. Therefore, the foamed base material 211 is easily deformed by following the movement of the skin 2, the biosensor 1 is flexible, and the electrode 30 can stably detect the electric signal while maintaining the contact with the skin 2. is important. In the biological sensor 1, the elongation at break of the foamed base material 211 can be set to 30% to 500%, and the foamed pasting layer 21 can be easily expanded and contracted. Therefore, even if the skin 2 moves, the biosensor 1 can maintain a state in which the sticking surface of the adhesive layer 212 for the base material to be attached to the foamed base material 211 is stably attached to the skin 2. Then, the biological sensor 1 can suppress the displacement of the attachment position of the electrode 30 by setting the static friction coefficient μ of the electrode 30 to 3.0 to 7.0. Therefore, when the biological sensor 1 is used, even if the subject moves due to exercise or the like, the magnitude of noise generated in the electrocardiogram can be suppressed, so that biological information can be measured stably and with high accuracy from the skin 2.

Further, in the biological sensor 1, since the foamed base material 211 has a breaking elongation rate of 30% to 500%, the volume of the voids generated inside the foamed base material 211 can be suppressed, so that moisture from the outside infiltrates. Can be suppressed. Therefore, the biosensor 1 can improve the durability.

Further, in the biological sensor 1, since the electrode 30 has a static friction coefficient μ of 3.0 to 7.0, the burden on the skin of the electrode 30 is suppressed, and the influence on the skin such as rough skin and skin covering is exerted. It can be suppressed. Therefore, the biosensor 1 can be safely used even if it is attached to the subject for a long time.

The biosensor 1 can be provided with a housing adhesive layer 22 on the surface on the housing 10 side, which is the upper surface of the foamed sticking layer 21 containing the foamed base material 211. As a result, even if the subject exercises and the skin 2 is stretched, the foamed sticking layer 21 maintains the adhesion to the housing 10, and a gap or the like is generated between the foamed sticking layer 21 and the housing 10. Since it can be suppressed, it is possible to suppress the invasion of moisture into the foamed sticking layer 21. Therefore, since the biosensor 1 can suppress the deterioration of the foamed pasting layer 21, the durability can be maintained.

The biological sensor 1 includes an adhesive layer 212 for a base material, a base material 41, and a sensor body 52, the housing 10 has a recess 11a formed in a concave shape on the skin 2 side, and the foamed base material 211 corresponds to the recess 11a. The hole portion 211a is provided at the position where the hole portion 211a is formed, and the accommodation space S can be formed by the recess 11a and the hole portion 211a. As a result, even if the biological sensor 1 is provided with the sensor main body 52 inside, the adhesive layer 212 for the base material can be suppressed from peeling from the skin 2 and can be maintained in a state of being attached to the skin 2.

The biological sensor 1 is provided with an adhesive layer 42 for attachment, and the adhesive layer 212 for a base material and the adhesive layer 42 for attachment can form a surface to be attached to a living body. As a result, even if the electrode 30 is attached to the adhesive layer 42 for attachment, the biological sensor 1 can secure a sufficient area to be attached to the skin 2, so that the adhesive layer 42 for attachment is peeled off from the skin 2. It is possible to prevent the electrode 30 from being attached to the skin 2 in a stable manner. Therefore, even if the biological sensor 1 is attached to the skin 2 of the subject for a long time, the biological information can be reliably detected from the skin 2 during use.

The biological sensor 1 can be provided with a through hole 31 in the electrode 30. By exposing the adhesive layer 212 for the base material from the through hole 31 to the sticking side, the adhesion between the electrode 30 and the skin 2 can be improved. Therefore, even if the electrode 30 is attached to the base material adhesive layer 212, the biosensor 1 can prevent the base material adhesive layer 212 from peeling off from the skin 2, and is stable to the skin 2. And can be maintained in a stuck state.

The biosensor 1 can use the foamed base material 211 as a base material. Since the foamed base material 211 has a porous structure, the biosensor 1 can easily follow the movement of the skin 2, suppress the increase in noise generated in the electrocardiogram waveform, and reduce discomfort to the subject. .. Further, since the water vapor generated from the skin 2 due to sweat or the like can be reliably released from the outside of the biosensor 1 via the foamed base material 211, the biosensor 1 can more reliably maintain the durability of the foamed base material 211. can do.

As described above, the biosensor 1 can be effectively used as a sticking type biosensor used by sticking to the skin 2 or the like of a living body. As described above, the biological sensor 1 can make it difficult for the sticking surface to be displaced from the skin 2 during use, has higher durability, and can reduce the burden on the skin 2. Therefore, for example, the biological sensor 1 can be used for living organisms. It can be suitably used for a wearable device for health care, which is attached to the skin or the like and has a high effect of suppressing noise generated in an electrocardiogram and requires safety for the skin.

Hereinafter, embodiments will be described in more detail with reference to Examples and Comparative Examples, but the embodiments are not limited to these Examples and Comparative Examples.

<Manufacturing and evaluation of electrode A>
[Preparation of conductive composition]
An aqueous solution containing 0.38 parts by mass of PEDOT / PSS pellets (“Orgacon DRY”, manufactured by Aghua Materials Japan) as a conductive polymer and modified polyvinyl alcohol (modified PVA) as a binder resin (modified polyvinyl alcohol concentration: 10). %, "Gosenex Z-410", manufactured by Nippon Synthetic Chemical Co., Ltd.) 10.00 parts by mass, glycerin (manufactured by Wako Junyaku Co., Ltd.) 2.00 parts by mass as a plasticizer, and 2-propane pale 1.60 parts by mass as a solvent. Parts and 6.50 parts by mass of water were added to the ultrasonic bath. Then, the aqueous solution containing these components was mixed in an ultrasonic bath for 30 minutes to prepare a uniform conductive composition aqueous solution A.

Since the concentration of the modified PVA in the aqueous solution containing the modified PVA is about 10%, the content of the modified PVA in the aqueous solution A of the conductive composition is 1.00 parts by mass. The balance is the solvent in the aqueous solution A of the conductive composition.

The contents of the conductive polymer, the binder resin and the plasticizer with respect to 100.0 parts by mass of the conductive composition were 11.2 parts by mass, 29.6 parts by mass and 59.2 parts by mass, respectively.

[Preparation of electrode sheet]
The prepared aqueous solution A of the conductive composition was applied onto a polyethylene terephthalate (PET) film using an applicator. Then, the PET film coated with the conductive composition aqueous solution A is conveyed to a drying oven (SPHH-201, manufactured by ESPEC), and the conductive composition aqueous solution A is heated and dried at 135 ° C. for 3 minutes to be conductive. A cured product of the sex composition was prepared. The cured product was punched (pressed) into a desired shape to form a sheet, and an electrode A, which is an electrode sheet (bioelectrode), was produced.

The contents of the conductive polymer, the binder resin and the plasticizer contained in the electrode A are the same as those of the conductive composition, and are 11.2 parts by mass, 29.6 parts by mass and 59.2 parts by mass, respectively. there were.

[Evaluation of electrode A]
The coefficient of static friction μ of the obtained electrode A was measured.
(Measurement of static friction coefficient μ)
The electrode A was cut into a size of 35 mm × 70 mm × 20 μm, and an electrode sheet sample was prepared. Next, the static friction coefficient μ with respect to the pseudo-skin of the electrode A was measured as follows using a static friction coefficient measuring machine (Tribogear TYPE: 10 manufactured by Shinto Kagaku Co., Ltd.). The pseudo-skin used for the evaluation is a bio-skin plate (manufactured by Viewlac Co., Ltd., product number P001-001, length 195 mm) that reproduces the affinity-hydrophobicity close to human skin and the wrinkles on the surface by processing the surface of the urethane elastomer film. × width 120 mm × thickness 5 mm) was used. Then, the bioskin plate is fixed to the ascending plate in the horizontal state, the electrode sheet sample is attached to the flat indenter of 75 mm in length × 35 mm in width, and it is allowed to stand for 30 seconds under the condition of the load of 1.47 N, and then the ascending velocity average. It was tilted at 10 degrees / 6 seconds, the friction angle θd when the planar indenter started to slide was read, and the static friction coefficient μ was calculated based on the following equation (I).
Static friction coefficient μ = tan (θd × π / 180) ・ ・ ・ (I)

Table 1 shows the content of each component contained in the aqueous solution A of the conductive composition and the drying temperature, and Table 2 shows the content of each component contained in the electrode A and the coefficient of electrostatic friction.

[Manufacturing and evaluation of electrodes B to f]
In the above <Preparation and evaluation of electrode A>, <Electrode A Preparation and evaluation of> was performed in the same manner.

Table 1 shows the content of each component contained in each of the conductive composition aqueous solutions B to f and the drying temperature, and Table 2 shows the content of each component contained in each of the electrodes B to f and the electrostatic friction coefficient. ..

<Preparation and evaluation of foam A>
[Preparation of foam A]
A rectangular foamed polyolefin sheet (“Folec®”, manufactured by Inoac Corporation, thickness: 0.5 mm) is foamed three times to form a sheet-shaped foamed base material, Foam A. Got Table 3 shows the material and foaming ratio of the polyolefin foam sheet.

[Measurement of breaking elongation of foam A in the long axis direction]
The elongation at break in the long axis direction of the foam A was measured using a tensile tester (AGS-J, manufactured by Shimadzu Corporation). For the foam A sample, use a rectangular sheet having a size of 10 mm on the short side × 70 mm on the long side × 0.5 mm in thickness, and grasp both ends of the sample of the foam A on the short side with a tensile test jig. Fixed. The tensile test conditions were as follows. Three foams A were prepared, and the average value of each measured value was taken as the breaking elongation rate of the foam A in the long axis direction. Table 3 shows the breaking elongation rate of the foam A in the major axis direction.
(Tensile test conditions)
-Width of foam A (maximum width of the short axis of foam A): 10 mm
-Distance between jigs for installing foam A: 50 mm
・ Tensile strength: 300 mm / min

<Preparation and evaluation of foams B to f>
In the above <Preparation and evaluation of foam A>, the foaming ratio of the polyolefin foam sheet was changed to the value shown in Table 3 to prepare foams B to f, and the elongation at break in the major axis direction of each foam was obtained. Was measured, but the procedure was the same as in <Preparation and evaluation of foam A>. The thickness of the sample of each foam was appropriately set to an arbitrary size.

Table 3 shows the material and foaming ratio of each polyolefin foam sheet used for producing each of the foams B to f, and the elongation at break in the major axis direction of each of the foams B to f.

<Example 1>
[Manufacturing of biosensor]
(Making the housing)
A housing was manufactured by forming a coat layer having a shore hardness of A40 made of silicone rubber on a support formed by using PET as a base resin and molding it into a predetermined shape.

(Making foam sheet)
Adhesive layer for base material (tape for long-term sticking) on the lower surface of foamed base material 1 (polyolefin foamed sheet (“Folec (registered trademark)”, manufactured by Inoac Corporation, thickness: 0.5 mm) formed in a rectangular shape). 1 (manufactured by Nitto Denko Corporation, thickness: 70 μm)) was formed to form a foamed adhesive layer. The long-term adhesive tape 1 had an adhesive-free adhesive-forming portion having a width of about 500 μm on its surface. A double-sided adhesive tape having a wavy pattern (web pattern) formed so that the width of the adhesive-free portion is about 1500 μm. After that, an adhesive layer for a housing is formed on the upper surface of the adhesive layer. (Silicone tape 1 (“ST503 (HC) 60”, manufactured by Nitto Denko Corporation, thickness: 60 μm) was formed to prepare a foamed sheet.

(Preparation of adhesive sheet for support)
Adhesive as an adhesive layer for sticking and an adhesive layer for sensors on both sides of the base material 1 (PET (“PET-50-SCA1 (white)”, manufactured by Mitsui & Co., Ltd.), thickness: 38 μm) formed in a rectangular shape. A supporting adhesive sheet, which is a skin tape to which 1 (“Permilol”, manufactured by Nitto Denko Corporation), moisture permeability: 21 (g / m ² · day)) was attached, was produced.

(Manufacturing of biosensor)
A sensor unit equipped with a battery and a control unit was installed in the center of the upper surface of the support adhesive sheet. After that, a pair of electrodes were attached to the sticking surface side of the adhesive layer for the base material while being sandwiched between the adhesive layer for the base material of the foam sheet and the adhesive sheet for support, and the electrodes and the wiring of the sensor portion were connected. .. Then, the housing was laminated on the foam sheet so that the sensor portion was arranged in the accommodation space formed by the foam sheet and the housing, and the biosensor was manufactured.

[Characteristic evaluation of biosensor]
As the characteristics of the obtained biosensor, the noise, the effect on the skin and the durability of the biosensor were evaluated.

(Evaluation of noise)
The obtained biosensor was attached to the skin of the subject for 24 hours, and the electrocardiogram was measured to obtain an electrocardiogram waveform. The electrocardiogram waveform is composed of P wave, QRS wave and T wave as shown in FIG. 7 in the absence of noise. As shown in FIG. 8, from the obtained ECG waveform, the magnitude of the amplitude of the RS wave consisting of the R wave and the S wave among the QRS waves is defined as the signal (S), and the waveform between the adjacent R waves is defined as the signal (S). The magnitude of the amplitude of the noise, which is the amplitude, was obtained as the noise (N). Then, the SN ratio, which is the ratio of the signal (S) to the noise (N), was obtained. As the SN ratio, a value obtained by extracting and averaging any three waveforms was used.

The obtained SN ratio was evaluated based on the following evaluation criteria, and the noise of the biosensor was evaluated. When the SN ratio is 8 or more, it is evaluated that there is almost no noise during walking (indicated as A in Table 4), and when the SN ratio is 5 or more and less than 8, it is evaluated that there is slight noise during walking. (In Table 4, it is expressed as B), and when the SN ratio is higher than 1 and less than 5, it is evaluated that R wave can be detected although there is a large noise during walking (indicated as C in Table 4), and the SN ratio. When is 1 or less, it was evaluated that there was a large noise during walking and the R wave could not be detected (indicated as D in Table 4).
Evaluation criteria
A: SN ratio is 8 or more B: SN ratio is 5 or more and less than 8 C: SN ratio is higher than 1 and less than 5 D: SN ratio is 1 or less

(Evaluation of the effect on the skin)
In the above (measurement of noise), after the biosensor was attached to the skin of the subject for 24 hours, the biosensor was peeled off from the skin, and the condition of the skin at the place where the biosensor was attached was visually observed. The effect on the skin was evaluated based on the following evaluation criteria. If there is no redness on the skin sticking part and there is no problem, it is judged to be excellent (indicated as A in Table 4), and if there is a little redness on the skin sticking part but there is no problem, it is good (not good). In Table 4, it is judged as B), and if redness is strongly seen on the skin sticking part, or if the skin is rough enough to prevent the biosensor from being stuck again on the skin sticking part. , Defect (indicated as C or D in Table 4).
Evaluation criteria
A: No redness is seen on the skin sticking part, no problem B: There is a little redness on the skin sticking part, but there is no problem C: Redness is strongly seen on the skin sticking part D: On the skin sticking part, Once again, the skin is so rough that the biosensor cannot be attached.

(Evaluation of durability)
In the above (noise measurement), the biosensor was attached to the skin of the subject for 24 hours. In addition, while the biosensor was attached to the skin of the subject, it was brought into contact with water based on "Waterproof standard: JIS C 0920-1993 (IPX4)". After the biosensor was attached to the skin of the subject for 24 hours, the biosensor was peeled off from the skin, the state of the biosensor was observed, and the durability was evaluated based on the following evaluation criteria. If there is no problem with water absorption or tearing on the biosensor, it is judged to be excellent (denoted as A in Table 4), and there is no problem within the range of use, and some water absorption or tearing is seen. If the effect on the measurement is limited, it is judged to be good (indicated as B in Table 4), and if it can be measured for 24 hours, it is good if it peels off due to water absorption or tearing. (Indicated as C in Table 4), and if the measurement could not be performed for 24 hours due to peeling or the like caused by water absorption or tearing, it was determined to be defective (indicated as D in Table 4).
Evaluation criteria
A: No problem with water absorption or tearing B: No problem within the range of use, some water absorption or tearing is seen, but the effect on measurement is limited C: Water absorption or tearing Peeling etc. occurred but can be measured for 24 hours D: Peeling etc. occurred due to water absorption or tearing and measurement cannot be performed for 24 hours

<Examples 2 to 6 and Comparative Examples 1 to 6>
In Example 1, the same procedure as in Example 1 was carried out except that the types of electrodes and foams used were changed.

Table 3 shows the types of electrodes and foams used in each of the examples and comparative examples, and the results of the characteristics of the biosensor.

From Table 4, it was confirmed that in Examples 1 to 6, the noise of the biosensor, the effect on the skin, and the durability all satisfied the conditions for use. On the other hand, in Comparative Examples 1 to 6, it was confirmed that the biosensor has a practical problem because at least one of noise, skin effect and durability does not satisfy the conditions for use.

Therefore, unlike the biosensors of Comparative Examples 1 to 6, the biosensors of Examples 1 to 6 have a foamed substrate having a breaking elongation rate of 30% to 500% and a static friction coefficient μ of 3.0 to 7. By providing an electrode of 0, even when the subject is exercising, the noise generated in the electrocardiogram can be suppressed and the electrocardiogram waveform can be stably acquired, and the burden on the skin is reduced while improving the durability. did it. Therefore, even if the biometric electrode according to the present embodiment is attached to the skin of the subject for a long time (for example, 24 hours), the electrocardiogram can be stably measured without burdening the subject continuously for a long time. It can be said that it can be used effectively.

As described above, the embodiments have been described, but the above embodiments are presented as examples, and the present invention is not limited to the above embodiments. The above embodiment can be implemented in various other embodiments, and various combinations, omissions, replacements, changes, and the like can be made without departing from the gist of the invention. These embodiments and modifications thereof are included in the scope and gist of the invention, and are also included in the scope of the invention described in the claims and the equivalent scope thereof.

1 Biosensor 2 Skin 10 Housing 20 Foaming sheet 21 Foaming sticking layer 211 Foaming base material 211a Hole 212 Adhesive layer for base material 22 Adhesive layer for housing 20 Electrode 31 Through hole 40 Supporting adhesive sheet 41 Base material 42 For sticking Adhesive layer 43 Adhesive layer for sensor 50 Sensor part 51 Flexible substrate (resin substrate)
52 Sensor body 54 Battery

One aspect of the biological sensor according to the present invention is a biological sensor attached to a living body to acquire a biological signal, which is a housing, a base material provided on the living body side of the housing, and the base material. 3. The electrode is provided with an electrode provided on the surface on the living body side, the breaking elongation rate of the base material is 30% to 500%, and the static friction coefficient of the electrode is 3. It is 5 to 7.0 ,
The breaking elongation of the base material is determined by grasping and fixing both ends of the base material on the short side of a rectangular sheet having a size of short side 10 mm × long side 70 mm × thickness 0.5 mm with a tensile test jig. , One or both of the pair of jigs are moved so that the tensile strength is 300 mm / min, and the rectangular sheet is pulled. Obtained from the ratio of the length in the direction to the length in the major axis direction or the minor axis direction before pulling the substrate.
The static friction coefficient of the electrode is determined by using a static friction coefficient measuring device to install the planar indenter to which the electrode is attached as a pseudo-skin by applying a load of 1.47 N to the surface of the bioskin plate, and then tilting the pseudo-skin. , It is obtained by applying the friction angle θd when the planar indenter starts to slide to the following equation (I) .
Fracture elongation of the base material = length in the major axis direction or minor axis direction when the substrate is fractured / length in the major axis direction or minor axis direction before the substrate is pulled ... (1)
Static friction coefficient μ = tan (θd × π / 180) ・ ・ ・ (I)

In examining the biosensor including the foamed sheet 20 and the electrode 30, the inventor of the present application considers the breaking elongation rate of the foamed base material 211 included in the foamed sheet 20 and the static friction coefficient μ of the electrode 30 to be the biosensor 1. We focused on the suppression of noise generated in the electrocardiogram, the improvement of the durability of the biological sensor 1, and the suppression of the burden on the skin 2 such as the covering of the skin. Then, the inventor of the present application states that when the breaking elongation rate of the foamed base material 211 is 30% to 500% and the static friction coefficient μ of the electrode 30 is 3.0 to 7.0, the biosensor 1 is the skin 2. It was discovered that it is possible to suppress the occurrence of misalignment on the sticking surface of. Therefore, it has been found that the biological sensor 1 can suppress noise generated in the electrocardiogram even when the subject is exercising such as walking or moving, and can stably acquire the waveform of the electrocardiogram (electrocardiogram waveform). At the same time, the inventor of the present application enhances the durability of the biosensor 1 by keeping the breaking elongation rate of the foamed base material 211 and the static friction coefficient μ of the electrode 30 within the above ranges, and the biosensor 1 is the skin 2. It was found that the burden on the skin can be reduced.

In the present embodiment, the static friction coefficient μ of the electrode 30 can be measured by using a static friction coefficient measuring machine (Tribogear TYPE: 10 manufactured by Shinto Kagaku Co., Ltd.). The coefficient of static friction μ of the electrode 30 with respect to the pseudo- skin can be measured as follows. For the pseudo- skin, a bio-skin plate (manufactured by Viewlac Co., Ltd., product number P001-001, length 195 mm x) that reproduces the surface wrinkles and affinity-hydrophobicity similar to that of dry human skin by processing the surface of the urethane elastomer film. (Width 120 mm × thickness 5 mm) or the like may be used. Then, the bioskin plate is fixed to the rising plate in a horizontal state, the electrode 30 is attached to a flat indenter having a predetermined size (for example, length 75 mm × width 35 mm), and the load is 1.47 N for 30 seconds. After standing still, it is tilted at an average ascending speed of 10 degrees / 6 seconds, and the friction angle θd when the planar indenter starts to slide is read. By applying this read friction angle θd to the following equation (I), the static friction coefficient μ can be obtained.
Static friction coefficient μ = tan (θd × π / 180) ・ ・ ・ (I)

[Evaluation of electrode A]
The coefficient of static friction μ of the obtained electrode A was measured.
(Measurement of static friction coefficient μ)
The electrode A was cut into a size of 35 mm × 70 mm × 20 μm, and an electrode sheet sample was prepared. Next, the static friction coefficient μ with respect to the pseudo- skin of the electrode A was measured as follows using a static friction coefficient measuring machine (Tribogear TYPE: 10 manufactured by Shinto Kagaku Co., Ltd.). The pseudo- skin used for the evaluation is a bio-skin plate (manufactured by Buerac Co., Ltd., product number P001-001, vertical) that reproduces the affinity-hydrophobicity close to human skin and the wrinkles on the surface by processing the surface of the urethane elastomer film. 195 mm × width 120 mm × thickness 5 mm) was used. Then, the bioskin plate is fixed to the ascending plate in the horizontal state, the electrode sheet sample is attached to the flat indenter of 75 mm in length × 35 mm in width, and it is allowed to stand for 30 seconds under the condition of the load of 1.47 N, and then the ascending velocity average. It was tilted at 10 degrees / 6 seconds, the friction angle θd when the planar indenter started to slide was read, and the static friction coefficient μ was calculated based on the following equation (I).
Static friction coefficient μ = tan (θd × π / 180) ・ ・ ・ (I)

Claims (8)

It is a biological sensor that is attached to a living body to acquire biological signals.
With the housing
The base material provided on the living body side of the housing and
An electrode provided on the surface of the base material on the living body side and
Equipped with
The breaking elongation rate of the base material is 30% to 500%, and the breaking elongation rate is 30% to 500%.
A biosensor in which the coefficient of static friction of the electrodes is 3.0 to 7.0. The biosensor according to claim 1, wherein an adhesive layer for a housing is provided on the surface of the foamed pasting layer containing the base material on the housing side. An adhesive layer for a base material provided on the surface of the base material on the living body side and to which the electrodes are attached,
A sensor body that is connected to the electrodes and acquires biological information,
The base material on which the sensor body is installed and
Equipped with
The housing has a recess formed in a concave shape on the living body side.
The base material has a hole at a position corresponding to the recess.
The biosensor according to claim 1 or 2, wherein a storage space in which the sensor main body is housed is formed by the recess and the hole. The adhesive layer for sticking provided on the living body side of the base material is provided.
The biological sensor according to claim 3, wherein a sticking surface to a living body is formed by the adhesive layer for a base material and the adhesive layer for sticking. The biosensor according to claim 3 or 4, wherein the electrode has a through hole through which the adhesive layer for a base material can be exposed while the electrode is attached to the adhesive layer for a base material. The biosensor according to any one of claims 1 to 5, wherein the base material is a foamed base material having a porous structure. The breaking elongation of the base material is such that the base material has a short side of 10 mm, a long side of 70 mm, and a thickness of 0.5 mm. The biosensor according to any one of claims 1 to 6, which is obtained by pulling at / minute. The coefficient of static friction of the electrode is the friction angle when the planar indenter to which the electrode is attached is placed on the surface of the pseudo-skin with a load of 1.47 N and then the pseudo-skin is tilted and the planar indenter starts to slide. The biosensor according to any one of claims 1 to 7, which is obtained by applying θd to the following formula.
Static friction coefficient μ = tan (θd × π / 180) ・ ・ ・ (I)

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