Biological sensor

Abstract

A biological sensor according to the present invention is provided with: a sensor main body for acquiring biological information; an adhesive electrode connected to the sensor main body; a first layer member having a housing space for housing the sensor main body, the electrode being provided on the lower surface thereof; and a second layer member attached to the lower surface of the first layer member so as to expose the electrode and cover the sensor body, the thickness of the electrode being 15 [mu] m or more, the area of the electrode being 2.0 cm2 to 5.0 cm2, the adhesive force of the electrode being 60 gf / [phi] 5 mm or more, and the occupancy of the electrode in the first layer member being 40% to 90% in a bottom view.

Description

Technical Field

[0001] The present invention relates to a biosensor. Background Art

[0002] In hospitals, clinics and other medical institutions, nursing facilities, and at home, for example, biosensors are used to measure biometric information such as electrocardiogram waveforms, pulse waves, brain waves, and myoelectricity. The biosensor has biometric electrodes that contact the biological body to obtain the biological information of the subject. When measuring the biometric information, the biosensor is attached to the skin of the subject, and the biometric electrodes are used to obtain electrical signals related to the biometric information, thereby measuring the biometric information.

[0003] As such a biosensor, for example, a biosensor is disclosed, which comprises: a sensor body; an electrode; a first layer component formed by stacking an upper sheet layer and capable of accommodating the sensor body; and a second layer component adhered to the surface of the first layer component on the biobody side and provided with the sensor body and the electrode exposed (for example, refer to patent document 1).

[0004] In this biosensor, while a first adhesive layer provided on the surface of the first layer component facing the biomolecule and a second adhesive layer provided on the surface of the second layer component facing the biomolecule are adhered to the skin, electrodes adhered to the first adhesive layer are brought into contact with the skin to obtain biomolecule information.

[0005] Prior art literature

[0006] Patent Literature

[0007] Patent Document 1: Japanese Patent No. 6947955 Summary of the invention

[0008] Problems to be solved by the invention

[0009] Here, Patent Document 1 does not study the thickness and area of ​​the electrode, the contact impedance with the skin, and the ease of peeling off from the biological surface. If the thickness or area of ​​the electrode is increased, the contact impedance with the biological surface becomes smaller, and the noise of the detected electrical signal is suppressed, but there is a possibility that the adhesion to the biological surface such as the skin of the subject is deteriorated and it is easy to peel off.

[0010] Biosensors are often attached to a biological surface such as the skin and used for a long time, and are required to detect biological information with high accuracy. Therefore, in order for the biosensor to stably and accurately obtain electrical signals related to biological information from a biological surface such as the skin for a long time, it is important for the biosensor to suppress the occurrence of noise in the detected electrical signal while being able to maintain a stable state of being attached to the biological surface.

[0011] An object of one aspect of the present invention is to provide a biosensor that suppresses the generation of noise during use and can be stably attached to a living body.

[0012] Methods for solving problems

[0013] One aspect of the biosensor according to the present invention comprises:

[0014] The sensor body that acquires biological information,

[0015] An adhesive electrode connected to the sensor body,

[0016] The electrode is provided below, and a first layer member has a storage space for storing the sensor body, and

[0017] A second layer member is attached to the lower surface of the first layer member so as to expose the electrode and cover the sensor body.

[0018] The thickness of the electrode is 15 μm or more, and the area of ​​the electrode is 2.0 cm 2 ~5.0cm 2 , the adhesion of the above-mentioned electrode is 60gf / Ф5mm or more,

[0019] The occupancy rate of the electrode in the first layer member is 40% to 90% when viewed from the bottom.

[0020] Effects of the Invention

[0021] One aspect of a biosensor according to the present invention can suppress the generation of noise during use and can be stably attached to a living body. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 It is a perspective view showing the overall structure of a biosensor according to an embodiment of the present invention.

[0023] Figure 2 It is a plan view showing an example of each component of the biosensor.

[0024] Figure 3 is the cross-sectional view of the biosensor in the length direction, Figure 1 II cross-sectional view.

[0025] Figure 4 for Figure 1 Bottom view of the biosensor.

[0026] Figure 5 To express that Figure 1 An explanatory diagram showing a state in which the biosensor is attached to the chest of a living body. DETAILED DESCRIPTION

[0027] The following is a detailed description of the embodiments of the present invention. In addition, in order to facilitate the understanding of the description, the same symbols are attached to the same components in each drawing, and repeated descriptions are omitted. In addition, the scales of the components in the drawings are sometimes different from the actual ones. In this specification, "to" indicating a numerical range means that the numerical values ​​recorded before and after it are included as the lower limit and upper limit unless otherwise specified.

[0028] <Biosensor>

[0029] The biosensor involved in this embodiment is described. In addition, the biosensor refers to the human body (human), as well as animals such as cows, horses, pigs, chickens, dogs and cats. The biosensor involved in this embodiment can be used for a biological body, and can be used as a human body. In this embodiment, as an example, the case where the biological body is a human is described.

[0030] The biosensor involved in this embodiment is a stick-on biosensor that is attached to a part of a living body (e.g., skin, scalp, or forehead) to measure biometric information. In this embodiment, a case where the biosensor is attached to a person's skin to measure an electrical signal (biometric signal) related to the person's biometric information is described.

[0031] Figure 1 It is a perspective view showing the overall structure of the biosensor according to the present embodiment. Figure 1 The left side of shows the appearance of the biosensor according to this embodiment. Figure 1 The right side of shows a state in which the components of the biosensor according to the present embodiment are disassembled. Figure 2 It is a plan view showing an example of each component of the biosensor. Figure 3 is the cross-sectional view of the biosensor in the length direction, Figure 1 II cross-sectional view.

[0032] Figure 1 and Figure 2 As shown, the biosensor 1 is a plate-like (sheet-like) member formed in a substantially elliptical shape in a plan view. Figure 2 and Figure 3As shown in the figure, the biosensor 1 includes a first layer member 10, an electrode 20, a sensor portion 30, and a second layer member 40, and the first layer member 10, the electrode 20, and the second layer member 40 are stacked in order from the first layer member 10 side toward the second layer member 40 side. In the biosensor 1, the first layer member 10, the electrode 20, and the second layer member 40 form an adhesive surface for skin 2 as an example of a living body. The biosensor 1 adheres the adhesive surface to the skin 2, measures the potential difference (polarization voltage) between the skin 2 and the electrode 20, and thereby measures an electrical signal (biological signal) related to the biological information of the subject.

[0033] Figure 1 to Figure 3 In the present invention, a three-dimensional orthogonal coordinate system with three axes (X-axis, Y-axis, and Z-axis) is used, and the width direction of the biosensor is the X-axis, the length direction is the Y-axis, and the height direction (thickness direction) is the Z-axis. The opposite direction (outer side) of the biosensor 1 pasted on one side (paste side) of the biological body (test object) is set as the +Z-axis, and the pasting side is set as the -Z-axis. In the following description, for the convenience of explanation, the +Z-axis is sometimes set as the upper side or top, and the -Z-axis is set as the lower side or bottom, which does not represent a general up-down relationship.

[0034] In addition, the biological signal is an electrical signal indicating, for example, an electrocardiogram waveform, a brain wave, a pulse, or the like.

[0035] The inventors of the present application have focused on the thickness, area, and adhesive force of the electrode 20 provided on the skin 2 side of the living body as the first layer member 10 when the biosensor 1 is used, and the influence of the proportion of the electrode 20 in the first layer member 10 on the suppression of noise generated when the biosensor 1 is used, and the effect of the adhesion to the living body. Furthermore, the inventors of the present application have found that by suppressing the volume and adhesiveness of the electrode 20 within a predetermined range and suppressing the proportion of the electrode 20 in the first layer member 10, the close contact state of the electrode 20 to the surface of the skin 2 is maintained and the close contact with the surface of the skin 2 is improved, thereby suppressing the occurrence of noise detected when the biosensor 1 is used, and improving the adhesion of the biosensor 1 to the living body.

[0036] [1st layer components]

[0037] Figure 1 and Figure 2 As shown, the first layer member 10 is provided by sequentially stacking a cover member 11 and an upper sheet 12. The cover member 11 and the upper sheet 12 have substantially the same outer shape in a plan view.

[0038] (covering member)

[0039] Figure 3As shown in the figure, the cover member 11 is located at the outermost side (+Z axis direction) of the biosensor 1 and is bonded to the upper surface of the upper sheet 12. The cover member 11 has a central portion in the longitudinal direction (Y axis direction) and has a central portion in the longitudinal direction (Y axis direction). Figure 1 The cover member 11 includes a protrusion 111 that protrudes in a substantially hemispherical shape in the height direction (+Z axis direction) of the cover member 11, and flat portions 112A and 112B provided at both end sides in the length direction (Y axis direction) of the cover member 11. The upper and lower surfaces of the protrusion 111 and the upper and lower surfaces of the flat portions 112A and 112B are formed flatly.

[0040] The covering member 11 has an opening formed so as to have a concave pit 111a formed on the inner side (sticking side) of the protruding portion 111. The pit 111a only needs to have a size that can accommodate at least a part of the sensor portion 30. On the inner side (sticking side) of the protruding portion 111, the pit 111a on the inner surface of the portion 111, the electrode 20 and the second layer member 40 form a storage space S for accommodating the sensor portion 30.

[0041] As a material for forming the covering member 11, for example, a flexible material such as silicone rubber, fluororubber, urethane rubber, etc. can be used. In addition, the covering member 11 can be formed by using a base resin such as polyethylene terephthalate (PET) as a support and laminating the above-mentioned flexible material on the surface of the support. By forming the covering member 11 using the above-mentioned flexible material, the sensor unit 30 arranged in the storage space S of the covering member 11 is protected, and the impact applied to the biosensor 1 from the upper side is absorbed and the impact applied to the sensor unit 30 is mitigated.

[0042] The thickness of the top and side walls of the protrusion 111 may be thicker than the thickness of the flat portions 112A and 112B. This can reduce the flexibility of the protrusion 111 compared to the flexibility of the flat portions 112A and 112B, and protect the sensor unit 30 from external forces applied to the biosensor 1.

[0043] The thickness of the top surface and the side wall of the protrusion 111 can be appropriately designed, for example, 1.5 mm to 3 mm. The thickness of the flat portions 112A and 112B can also be appropriately designed, for example, 0.5 mm to 1 mm.

[0044] The thin flat portions 112A and 112B are more flexible than the protruding portion 111, so when the biosensor 1 is attached to the skin 2, it is easy to deform to follow the deformation of the surface of the skin 2 caused by body movements such as stretching, bending, and twisting. Therefore, when the surface of the skin 2 is deformed, the stress applied to the flat portions 112A and 112B can be alleviated, and the biosensor 1 can be difficult to peel off from the skin 2.

[0045] The outer periphery of the flat portions 112A and 112B may have a shape in which the thickness gradually decreases toward the ends. This can further improve the flexibility of the outer periphery of the flat portions 112A and 112B, and can improve the sense of installation when the biosensor 1 is attached to the skin 2, compared with a case where the thickness of the outer periphery of the flat portions 112A and 112B is not reduced.

[0046] The hardness (strength) of the covering member 11 can be designed to be an appropriate arbitrary size, for example, it can be 40 to 70. If the hardness of the covering member 11 is within the above preferred range, when the skin 2 is stretched by body movement, it can be unaffected by the covering member 11, and the upper sheet 12, the electrode 20 and the second layer member 40 can be easily deformed according to the movement of the skin 2. In addition, the hardness (hardness) refers to the Shore A hardness. In this specification, the Shore A hardness refers to the value measured in accordance with ISO7619 (JIS K 6253: 2012). The Shore A hardness is an A-type durometer hardness measured by a rubber durometer (A-type durometer) with an A-type (cylindrical) indenter.

[0047] (Upper piece)

[0048] Figure 3 As shown in the figure, the upper sheet 12 is bonded to the lower surface of the cover member 11. The upper sheet 12 has a through hole 12a at a position opposite to the protrusion 111 of the cover member 11. Through the through hole 12a, the sensor body 32 of the sensor unit 30 is not blocked by the upper sheet 12, and can be stored in the storage space S formed by the recess 111a on the inner surface of the cover member 11 and the through hole 12a.

[0049] The upper sheet 12 includes a first substrate 121 , a first adhesive layer 122 having the electrode 20 adhered to a surface of the first substrate 121 facing the electrode 20 , and an upper adhesive layer 123 provided on a surface opposite to the surface of the first substrate 121 facing the electrode 20 .

[0050] ((First base material))

[0051] Figure 3 As shown in the figure, the first substrate 121 is provided on the pasting side which is the opening side of the cover member 11. The first substrate 121 is formed in a sheet shape. The first substrate 121 has a porous structure and can be formed using a porous body having flexibility, waterproofness, and moisture permeability. As the porous body, for example, a foaming raw material (foam) having a bubble structure such as continuous bubbles, independent bubbles, and semi-independent bubbles can be used. Thus, water vapor brought by sweat or the like generated from the skin 2 to which the biosensor 1 is pasted can be released to the outside of the biosensor 1 via the first substrate 121.

[0052] The moisture permeability of the first substrate 121 is preferably 100 g / (m 2 ·day)~5000g / (m 2 ·day). By setting the moisture permeability of the first substrate 121 to 100 g / (m 2 ·day)~5000g / (m 2 ·day), so that the first substrate 121 can allow water vapor that penetrates from one side to pass through the first substrate 121 and be stably released from the other side.

[0053] As a material forming the first substrate 121, for example, thermoplastic resins such as polyurethane resins, polystyrene resins, polyolefin resins, silicone resins, acrylic resins, vinyl chloride resins, and polyester resins can be used. As the first substrate 121, for example, FOLEC manufactured by INOAC CORPORATION can be used.

[0054] The thickness of the first substrate 121 can be appropriately set, and may be, for example, 0.5 mm to 1.5 mm.

[0055] The first base material 121 has a through hole 121a at a position facing the protruding portion 111 of the cover member 11. By providing the first adhesive layer 122 and the upper adhesive layer 123 on the surface other than the through hole 121a of the first base material 121, through holes 122a and 123a can be formed in the first adhesive layer 122 and the upper adhesive layer 123. The through holes 121a, 122a, and 123a form the through hole 12a.

[0056] In addition, the first substrate 121 may be a substrate without a porous structure as long as it has flexibility, waterproofness, and moisture permeability. The first substrate 121 has flexibility, waterproofness, and moisture permeability, so that the first substrate 121 is easy to extend in contact with the skin 2, and can maintain the state of contact with the skin 2, and can suppress the intrusion of liquid into the gap between the first substrate 121 and the upper adhesive layer 123. In addition, water vapor brought by sweat or the like generated by the skin 2 to which the biosensor 1 is attached can be released to the outside of the biosensor 1 through the first substrate 121. Therefore, the upper sheet 12 is easy to maintain the bonding durability.

[0057] As the material of the substrate without a porous structure, as described above, for example, thermoplastic resins such as polyurethane resins, polystyrene resins, polyolefin resins, silicone resins, acrylic resins, vinyl chloride resins, and polyester resins can be used. In the case where the first substrate 121 is a material of a substrate without a porous structure, as the first substrate 121, for example, a polyurethane sheet such as S-URS manufactured by Japan Matai can be used.

[0058] ((First adhesive layer))

[0059] Figure 3 As shown, the first adhesive layer 122 is provided in a state of being adhered to the surface of the first substrate 121 that is opposite to the electrode 20. The first adhesive layer 122 is located on the surface of the first substrate 121 on the biological body side (-Z axial direction), and has the functions of bonding the skin 2 to the first substrate 121, bonding the first substrate 121 to the second substrate 41, and bonding the first substrate 121 to the electrode 20.

[0060] The first adhesive layer 122 may have moisture permeability. Thus, as described later, water vapor caused by sweat or the like generated by the skin 2 to which the biosensor 1 is attached can escape to the first base material 121 through the first adhesive layer 122, and be released from the first base material 121 to the outside of the biosensor 1. When the first base material 121 has a bubble structure as described above, water vapor can be released to the outside of the biosensor 1 through the first adhesive layer 122. Thus, it is possible to suppress sweat or water vapor from being retained at the interface between the skin 2 to which the biosensor 1 is attached and the first layer member 10. As a result, the moisture retained at the interface between the skin 2 and the first adhesive layer 122 weakens the adhesive force of the first adhesive layer 122, and it is possible to suppress the biosensor 1 from peeling off from the skin 2.

[0061] The moisture permeability of the first adhesive layer 122 is preferably, for example, 1 g / (m 2 The moisture permeability of the first adhesive layer 122 can be 10000 g / (m 2 If the moisture permeability of the first adhesive layer 122 is 1g / (m 2 · days) or more, when the first adhesive layer 122 is attached to the skin 2, sweat and the like conducted from the first adhesive layer 122 can be transmitted to the outside, thereby reducing the load on the skin 2.

[0062] As a material forming the first adhesive layer 122, a material having pressure-sensitive adhesive properties is preferable, and for example, an acrylic pressure-sensitive adhesive can be used.

[0063] The first adhesive layer 122 may be an adhesive tape formed of the above-mentioned materials.

[0064] The first adhesive layer 122 can be formed with a wave-shaped pattern (reticular pattern) formed by repeated alternation of recesses thinner than other parts (or having a thickness of zero) on its surface. As the first adhesive layer 122, for example, an adhesive tape having a reticular pattern formed on its surface can be used. The first adhesive layer 122 has a reticular pattern on its surface, so that both the part where the adhesive on the surface of the first adhesive layer 122 is easy to contact with the organism and the part where it is difficult to contact with the organism exist. Since both the part where the adhesive exists and the part where the adhesive does not exist exist on the surface of the first adhesive layer 122, the part where the surface of the first adhesive layer 122 is easy to contact with the organism can be located. The thinner the adhesive is, the higher the moisture permeability of the first adhesive layer 122 tends to be. Therefore, the first adhesive layer 122 forms a reticular pattern on its surface, and has a part where the thickness of the adhesive is thin, so that compared with the case where the reticular pattern is not formed, it is possible to maintain adhesion while improving moisture permeability. In addition, the shape of the concave portion may be a linear shape or a circular shape other than a wave shape.

[0065] The width of the adhesive forming part and the non-adhesive part can be appropriately designed. For example, the width of the adhesive forming part is preferably 500 μm to 1000 μm, and the width of the non-adhesive part is preferably 1500 μm to 5000 μm. If the widths of the adhesive forming part and the non-adhesive part are each within the above-mentioned preferred range, the first adhesive layer 122 can maintain adhesive strength while exhibiting excellent moisture permeability.

[0066] The thickness of the first adhesive layer 122 can be set arbitrarily and is preferably 10 μm to 300 μm, more preferably 50 μm to 200 μm, and further preferably 70 μm to 110 μm. When the thickness of the first adhesive layer 122 is 10 μm to 300 μm, the biosensor 1 can be made thinner.

[0067] The adhesive force of the first adhesive layer 122 can be set appropriately and arbitrarily. For example, for a baking plate, it is preferably 3.0N / 10mm to 20N / 10mm, more preferably 4.0N / 10mm to 15N / 10mm, and further preferably 5.0N / 10mm to 10N / 10mm. If the adhesive force of the first adhesive layer 122 is 3.0N / 10mm to 20N / 10mm, the first adhesive layer 122 constitutes a part of the adhesive surface of the biosensor 1 to the surface of the skin 2, thereby achieving improved adhesion of the biosensor 1 to the living body.

[0068] ((Adhesive layer for the upper part))

[0069] Figure 3As shown in the figure, the upper adhesive layer 123 is provided in a state of being attached to the surface opposite to the surface of the first substrate 121 that faces the electrode 20. The upper adhesive layer 123 is attached to a position corresponding to the flat surface of the attachment side (-Z axial direction) of the cover member 11 on the upper surface of the first substrate 121, and has the function of bonding the first substrate 121 and the cover member 11.

[0070] As a material forming the upper adhesive layer 123 , a silicone-based adhesive, a silicone tape, or the like can be used.

[0071] The thickness of the upper adhesive layer 123 can be appropriately set, and can be set to, for example, 10 μm to 300 μm.

[0072] [electrode]

[0073] Figure 3 As shown in FIG. 1 , the electrode 20 is attached to the skin 2 by connecting a portion of the sensor body 32 side of the electrode 20 to the wiring 331A and 331B below the surface of the attachment side (-Z axis direction) of the first adhesive layer 122, and sandwiching the first adhesive layer 122 and the lower adhesive layer 42. The portion of the electrode 20 that is not sandwiched between the first adhesive layer 122 and the lower adhesive layer 42 is in contact with the biological body. When the biosensor 1 is attached to the skin 2, the electrode 20 is in contact with the skin 2, thereby being able to detect a biological signal. In addition, the electrode 20 can be buried in a state where it is exposed so that the second substrate 41 can contact the skin 2.

[0074] The electrode 20 is composed of a pair of electrodes 20A and 20B. Figure 3 As shown in the figure, the electrode 20A is arranged on the left side in the figure, and the electrode 20B is arranged on the right side in the figure. The electrode 20A contacts the terminal portion 332A at one end side (inner side) in the length direction (Y-axis direction), and the electrode 20B contacts the terminal portion 332B at one end side (inner side) in the length direction (Y-axis direction). The pair of electrodes 20A and 20B have substantially the same shape.

[0075] In addition, one end side of the electrode 20A in contact with the terminal portion 332A of the sensor portion 30 is set as the opposing portion 201A, and one end side of the electrode 20B in contact with the terminal portion 332B of the sensor portion 30 is set as the opposing portion 201B. The portion of the electrode 20A that is not in contact with the terminal portion 332A (the other end side (outer side) in the length direction (Y-axis direction)) is set as the exposed portion 202A, and the portion of the electrode 20B that is not in contact with the terminal portion 332B (the other end side (outer side) in the length direction (Y-axis direction)) is set as the exposed portion 202B.

[0076] The electrode 20 may have any shape such as a sheet shape.

[0077] The shape of the electrode 20 when viewed from above is not particularly limited, and can be designed to any appropriate shape depending on the application, etc. The electrodes 20A and 20B are each as shown in FIG. Figure 2 As shown, in a plan view, the facing portions 201A and 201B on one end side may be formed in a rectangular shape, and the exposed portions 202A and 202B on the other end side may be formed in an arc shape.

[0078] Electrodes 20A and 20B are as follows Figure 2 and Figure 3 As shown in FIG. 1 , the electrode 20 may have through holes 203A and 203B which are elongated in the width direction (X-axis direction) and are arranged at one end side (inner side) in the length direction (Y-axis direction), and through holes 204A and 204B which are circular in shape and are arranged at the other end side (outer side) in the length direction (Y-axis direction). Thus, the electrode 20 can be exposed to the pasting side from the through holes 203A and 203B, and the through holes 204A and 204B in a state of being pasted to the first adhesive layer 122, thereby improving the adhesion between the electrode 20 and the skin 2. In addition, the number of through holes 203A and 203B, and through holes 204A and 204B is not particularly limited, and can be appropriately set according to the size of the opposing parts 201A and 201B of the electrode 20.

[0079] The electrode 20 is preferably an electrode having adhesiveness (adhesive electrode). When the electrode 20 is an adhesive electrode, the electrode 20 can be formed using an adhesive electrode sheet formed in a sheet form using an adhesive conductive composition containing a conductive polymer, a binder resin, and a moisturizing agent.

[0080] As conductive polymers, for example, polythiophene conductive polymers, polyaniline conductive polymers, polypyrrole conductive polymers, polyacetylene conductive polymers, polyphenylene conductive polymers and derivatives thereof, and composites thereof, etc. can be used. They can be used alone or in combination of two or more. Among these, it is preferred to use a composite doped with polyaniline as a dopant in polythiophene. In the composite of polythiophene and polyaniline, from the perspective of lower contact impedance with a biological body and high conductivity, it is more preferred to use PEDOT / PSS doped with polystyrene sulfonic acid (poly-4-styrene sulfonate; PSS) in poly-3,4-ethylenedioxythiophene (PEDOT).

[0081] The binder resin includes an aqueous emulsion adhesive. The aqueous emulsion adhesive has the function of improving the adhesiveness and flexibility of the electrode 20. Therefore, the aqueous emulsion adhesive is included in the electrode 20, so that the electrode 20 can have low elasticity and improve the followability to the unevenness of the surface of the skin 2.

[0082] As the water-based emulsion adhesive, an acrylic emulsion adhesive can be used.

[0083] The acrylic emulsion adhesive is preferably a silane emulsion adhesive containing a water-dispersible copolymer and an organic liquid component compatible with the water-dispersible copolymer.

[0084] The water-dispersible copolymer is a polymer obtained by copolymerizing an alkyl (meth)acrylate and a copolymerizable silane-based monomer in a monomer mixture containing an alkyl (meth)acrylate.

[0085] The monomer mixture containing an alkyl (meth)acrylate refers to a monomer mixture containing an alkyl (meth)acrylate as a main component, preferably containing 50 wt % to 100 wt % of the alkyl (meth)acrylate.

[0086] As the alkyl (meth)acrylate, a linear or branched alkyl ester having an alkyl group with 1 to 15 carbon atoms, preferably 1 to 9 carbon atoms, is used. Specifically, for example, alkyl (meth)acrylate having a linear or branched alkyl group such as methyl (meth)acrylate, ethyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, pentyl (meth)acrylate, hexyl (meth)acrylate, heptyl (meth)acrylate, n-octyl (meth)acrylate, isooctyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, n-nonyl (meth)acrylate, isononyl (meth)acrylate, decyl (meth)acrylate, undecyl (meth)acrylate, tridecyl (meth)acrylate, etc., can be mentioned. These can be used alone or in combination of two or more.

[0087] The monomer mixture containing the alkyl (meth)acrylate may contain a carboxyl group-containing monomer copolymerizable with the alkyl (meth)acrylate.

[0088] The carboxyl group-containing monomer copolymerizable with the (meth)acrylic acid alkyl ester is not particularly limited as long as it is a polymerizable compound containing a carboxyl group in its structure and is copolymerizable with the (meth)acrylic acid alkyl ester, and examples thereof include (meth)acrylic acid, itaconic acid, maleic acid, maleic anhydride, 2-methacryloyloxyethylsuccinic acid, etc. In particular, acrylic acid is preferred.

[0089] The carboxyl group-containing monomer is preferably contained in an amount of 0.1 wt % to 10 wt % based on 100 wt % of the monomer mixture containing the (meth)acrylic acid alkyl ester from the viewpoint of hydrolysis of the silane-based monomer and adjustment of the obtained adhesiveness.

[0090] As the silane monomers copolymerizable with (meth) alkyl acrylate, if it is a polymerizable compound with silicon atoms, the monomers copolymerizable with (meth) alkyl acrylate are not particularly limited, and from the perspective of excellent copolymerizability for (meth) alkyl acrylate, preferably silane compounds with (meth) acryloyl groups such as (meth) acryloyloxyalkylsilane derivatives. As silane monomers, for example, 3-(meth) acryloyloxypropyl trimethoxysilane, 3-(meth) acryloyloxypropyl triethoxysilane, 3-(meth) acryloyloxypropyl methyl dimethoxysilane, 3-(meth) acryloyloxypropyl methyl diethoxysilane, etc. can be cited. These silane monomers can be used alone or in combination of two or more.

[0091] In addition, as silane monomers other than the above, for example, vinyltrimethoxysilane, vinyltriethoxysilane, 4-vinylbutyltrimethoxysilane, 4-vinylbutyltriethoxysilane, 8-vinyloctyltrimethoxysilane, 8-vinyloctyltriethoxysilane, 10-methacryloyloxydecyltrimethoxysilane, 10-acryloyloxydecyltrimethoxysilane, 10-methacryloyloxydecyltriethoxysilane, 10-acryloyloxydecyltriethoxysilane, etc. can also be used.

[0092] The silane-based monomer is preferably copolymerized in an amount of 0.005 wt % to 2 wt % based on 100 wt % of the monomer mixture containing the alkyl (meth)acrylate.

[0093] The silane monomer is copolymerized with a monomer mixture containing an alkyl (meth)acrylate, so that the silane compound as a crosslinking point can be in a state of being uniformly present in the molecules of the resulting copolymer. Thus, whether the aqueous emulsion adhesive is a water-dispersible type or not, the inside and outside of the particles of the aqueous emulsion adhesive are uniformly crosslinked, so that the cohesive force is excellent, and the addition of an organic liquid component makes it low in skin irritation, and in addition, it has both excellent fixation and sweat-resistant fixation.

[0094] The water-dispersible copolymer can be formed by copolymerizing the monomers copolymerizable with the alkyl (meth)acrylate other than the above-mentioned silane monomers and the monomers containing carboxyl groups as needed. The monomers copolymerizable with the alkyl (meth)acrylate other than the silane monomers and the monomers containing carboxyl groups can be used for the purpose of adjusting the cohesive force of the electrode 20 when the water-based emulsion adhesive is formed in a sheet form, etc., improving the compatibility with the organic liquid component, etc., and the amount used can replace a part of the content of the alkyl (meth)acrylate and can be arbitrarily set according to the purpose.

[0095] Examples of the monomer copolymerizable with the alkyl (meth)acrylate other than the silane monomer and the carboxyl group-containing monomer include sulfonyl group-containing monomers such as styrenesulfonic acid, allylsulfonic acid, sulfopropyl (meth)acrylate, (meth)acryloyloxynaphthalenesulfonic acid, and acrylamidomethylpropanesulfonic acid; hydroxyl group-containing monomers such as hydroxyethyl (meth)acrylate and hydroxypropyl (meth)acrylate; amide group-containing monomers such as (meth)acrylamide, dimethyl (meth)acrylamide, N-butylacrylamide, N-methylol (meth)acrylamide, and N-methylolpropane (meth)acrylamide; alkylaminoalkyl (meth)acrylates such as aminoethyl (meth)acrylate, dimethylaminoethyl (meth)acrylate, and tert-butylaminoethyl (meth)acrylate; and (meth)acrylates containing an alkoxy group (or an ether bond in the side chain) such as methoxyethyl (meth)acrylate, ethoxyethyl (meth)acrylate, (meth)acrylate alkoxyalkyl esters such as methoxyethylene glycol (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, methoxyethylene glycol (meth)acrylate, methoxydiglycol (meth)acrylate, methoxypolyethylene glycol (meth)acrylate, and methoxypolypropylene glycol (meth)acrylate, (meth)acrylonitrile, vinyl acetate, vinyl propionate, N-vinyl-2-pyrrolidone, methylvinylpyrrolidone, vinylpyridine, vinylpiperidine, vinylpyrimidine, vinylpiperazine, vinylpyrazine, vinylpyrrole, vinylimidazole, vinylcaprolactam, vinyloxazole, and vinylmorpholine. These can be used alone or in combination of two or more.

[0096] The water-dispersible polymer can be prepared as a water dispersion of an alkyl (meth)acrylate copolymer by, for example, subjecting a monomer mixture containing an alkyl (meth)acrylate and a mixture of a silane-based monomer to ordinary emulsion polymerization.

[0097] As the polymerization method, general batch polymerization, continuous dropwise polymerization, divided dropwise polymerization, etc. can be adopted, and the polymerization temperature is, for example, 20°C to 100°C.

[0098] The polymerization initiator used for the polymerization is not particularly limited, and a general component used as a polymerization initiator can be used.

[0099] During polymerization, a chain transfer agent may be used to adjust the degree of polymerization. The chain transfer agent is not particularly limited, and a general component used as a chain transfer agent may be used.

[0100] In addition to the above-mentioned method, the water-dispersible copolymer can be prepared by obtaining a copolymer of a monomer mixture containing a (meth)acrylate and a silane-based monomer by a method other than emulsion polymerization and then dispersing the copolymer in water with an emulsifier.

[0101] The organic liquid component contained in the acrylic emulsion adhesive is blended with the water-dispersible copolymer to maintain good adhesiveness to the surface of the skin 2 and reduce keratin damage and pain during peeling.

[0102] The organic liquid component is preferably liquid at room temperature and has good compatibility with the water-dispersible copolymer. In addition, "compatible" means that the organic liquid component is uniformly dissolved and taken up in the water-dispersible copolymer and cannot be visually confirmed to be separated.

[0103] Examples of the organic liquid component include esters of monobasic or polybasic acids having 8 to 18 carbon atoms and branched alcohols having 14 to 18 carbon atoms, and esters of unsaturated fatty acids or branched acids having 14 to 18 carbon atoms and alcohols having a valence of less than 4.

[0104] Examples of esters of a monobasic acid or polybasic acid having 8 to 18 carbon atoms and a branched alcohol having 14 to 18 carbon atoms include isostearyl laurate, isocetyl myristate, octyldodecyl myristate, isostearyl palmitate, isocetyl stearate, octyldodecyl oleate, diisostearyl adipate, diisocetyl sebacate, trioleyl trimellitate, and triisocetyl trimellitate.

[0105] Examples of the unsaturated fatty acid or branched acid having 14 to 18 carbon atoms include myristic acid, oleic acid, linoleic acid, linolenic acid, isopalmitic acid, and isostearic acid.

[0106] Examples of the tetravalent or lower alcohol include ethylene glycol, propylene glycol, glycerin, trimethylolpropane, pentaerythritol, and sorbitan.

[0107] The content of the organic liquid component can be appropriately and arbitrarily set according to the types of the water-dispersible copolymer and the organic liquid component, and can be, for example, 20 wt % to 80 wt % based on 100 wt % of the water-dispersible copolymer.

[0108] When the acrylic emulsion adhesive is a silane emulsion adhesive, specifically, a silane emulsion adhesive containing 2-ethylhexyl acrylate, methyl methacrylate, acrylic acid, and 3-methacryloxypropyltrimethoxysilane can be used as the acrylic emulsion adhesive.

[0109] In addition, the acrylic emulsion adhesive can be a two-component or three-component acrylic emulsion adhesive containing a monomer mixture containing an alkyl (meth)acrylate and a carboxyl group-containing monomer. These can contain a solvent and other components in appropriate predetermined amounts within a range in which the performance can be exerted.

[0110] The monomer mixture containing alkyl (meth)acrylate contained in the two-component or three-component acrylic emulsion adhesive is the same as the monomer mixture containing alkyl (meth)acrylate contained in the above-mentioned silane emulsion adhesive, and therefore the details are omitted.

[0111] The carboxyl group-containing monomer is preferably a carboxyl group-containing monomer copolymerizable with an alkyl (meth)acrylate. The carboxyl group-containing monomer copolymerizable with an alkyl (meth)acrylate is the same as the carboxyl group-containing monomer contained in the monomer mixture containing an alkyl (meth)acrylate, and thus details thereof are omitted.

[0112] As the two-component acrylic emulsion adhesive, specifically, an adhesive containing 2-ethylhexyl acrylate as a monomer mixture containing an alkyl (meth)acrylate, and acrylic acid as a monomer mixture containing a carboxyl group can be used.

[0113] As the three-component acrylic emulsion adhesive, specifically, an adhesive containing 2-ethylhexyl acrylate and methyl methacrylate as a monomer mixture containing an alkyl (meth)acrylate, and acrylic acid as a monomer mixture containing a carboxyl group can be used.

[0114] The average particle size of the aqueous emulsion adhesive is preferably 100 nm to 1.0 μm, more preferably 100 nm to 500 nm, and even more preferably 100 nm to 300 nm. When the average particle size is within the above preferred range, adhesive force and water resistance can be imparted to the electrode 20 .

[0115] The shape of the aqueous emulsion adhesive is not particularly limited, and may be, for example, spherical, ellipsoidal, spindle-shaped, crushed, plate-shaped, columnar, or the like.

[0116] The average particle size refers to the volume average particle size using the effective diameter. The average particle size is, for example, the particle size distribution curve obtained by measuring the particle size distribution of an emulsion adhesive or an acrylic emulsion adhesive by laser diffraction, scattering, or dynamic light scattering, and the particle size (median particle size) at which the cumulative amount is accumulated from the direction of the smaller particles on a volume basis to occupy 50%.

[0117] The content of the binder resin is preferably 35 wt% to 90 wt%, more preferably 40 wt% to 85 wt%, and further preferably 50 wt% to 80 wt%. If the content of the binder resin is within the above preferred range, adhesion and softness can be imparted to the electrode 20, and a decrease in conductivity can be suppressed.

[0118] The humectant has the function of improving the conductivity of the electrode 20, and improving the adhesion and flexibility. As the humectant, polyol compounds such as glycerol, ethylene glycol, propylene glycol, sorbitol, these polymers, N-methylpyrrolidone (NMP), dimethylformaldehyde (DMF), N-N'-dimethylacetamide (DMAc), aprotic compounds such as dimethyl sulfoxide (DMSO) and the like can be cited. These can be used alone or in combination of two or more. Among these, glycerol is preferably used from the viewpoint of compatibility with other components.

[0119] The content of the moisturizer is preferably 2wt% to 60wt% relative to 100wt% of the electrode, more preferably 3wt% to 50wt%, and further preferably 5wt% to 35wt%. If the content of the moisturizer is within the above preferred range, the adhesion of the electrode 20 can be increased, and the high adhesion to the surface of the skin 2 can be maintained, and the storage elastic modulus can be reduced, and the viscoelasticity can be increased, thereby suppressing the size of the noise generated during use. In addition, it is possible to suppress the absorption of water from the outside of the electrode 20 and suppress swelling.

[0120] The thickness of the electrode 20 is 15 μm or more, preferably 20 μm to 100 μm, more preferably 25 μm to 90 μm, and further preferably 30 μm to 80 μm. If the thickness of the electrode 20 is 15 μm or more, the electrode 20 can be given sufficient strength, flexibility, low resistance, and conductive stability during deformation.

[0121] The thickness of the electrode 20 refers to the length in the direction perpendicular to the surface of the electrode 20. The thickness of the electrode 20 is, for example, the thickness when measuring any location in the cross section of the electrode 20. When measuring multiple locations at any location, it may be the average value of the thicknesses at these measurement locations.

[0122] The area of ​​electrode 20 is 2.0 cm 2 ~5.0cm 2 , preferably 2.5 cm 2 ~4.5cm 2 , more preferably 2.7 cm 2 ~4.0cm 2 If the area of ​​electrode 20 is 2.0 cm 2 ~5.0cm 2 , which can make the electrode 20 have sufficient conductive stability and adhesion.

[0123] The area of ​​the electrode 20 can be measured using a common measurement method, for example, by binarizing an image of the surface of the electrode 20 using common image analysis software (eg, ImageJ), and calculating the area of ​​the electrode 20 in dot (pixel) units.

[0124] The adhesion of the electrode 20 is 60 gf / Ф5mm or more, preferably 63 gf / Ф5mm or more, and more preferably 65 gf / Ф5mm or more. In addition, the upper limit of the adhesion of the electrode 20 is not particularly limited, and can be appropriately selected according to the size, shape, material, etc. of the electrode 20. For example, it can be 200 gf / Ф5mm or less. If the adhesion of the electrode 20 is 60 gf / Ф5mm or more, the electrode 20 can have sufficient adhesion while having conductivity.

[0125] In addition, in this specification, the adhesive force refers to the adhesive force when the electrode 20 is made into a circle with a diameter of 5 mm. The adhesive force of the electrode 20 can be measured using a general measurement method, for example, it can be measured using a general wrinkle tester, etc. As the measurement conditions, for example, the pressing load on the electrode 20 can be 50 gf, the pressing speed can be 0.01 mm / s, the holding time can be 1.0 s, and the pulling speed can be 1 mm / s.

[0126] When viewed from the bottom, the electrode 20 occupies 40% to 90% of the first layer member 10, preferably 45% to 80%, and more preferably 50% to 70%. If the occupancy is 40% to 90%, the electrode 20 can have sufficient strength, flexibility and adhesion while having conductivity.

[0127] In addition, the occupancy rate of the electrode 20 in the first layer member 10 is, when the bottom surface of the first layer member 10 is viewed, Figure 4 As shown in FIG. 1 , when the bottom surface of the biosensor is viewed, the ratio of the electrode 20 under the area (area) of the first layer member 10 and the electrode 20 exposed as the attachment surface to the biological body. That is, the occupancy rate of the electrode 20 in the first layer member 10 is the ratio of the area S2 of the electrode 20 to the sum of the area S1 of the first layer member 10 and the area S2 of the electrode 20, as shown in the following formula (1).

[0128] Occupancy rate of the electrode 20 in the first layer member 10 (%) = area S2 of the electrode 20 / (area S1 of the first layer member 10 + area S2 of the electrode 20) × 100 (1)

[0129] (Sensor part)

[0130] Figure 2 As shown, the sensor section 30 includes a flexible substrate 31 , a sensor body 32 , and connection sections 33A and 33B connected to the sensor body 32 .

[0131] The flexible substrate 31 is a resin substrate on which various components for acquiring biological information are mounted, and the flexible substrate 31 is provided with a sensor body 32 and connection parts 33A and 33B.

[0132] Figure 2 As shown, the sensor body 32 includes a component mounting portion 321 and a battery mounting portion 322 as a control portion, and acquires biological information.

[0133] The component mounting section 321 includes a CPU and an integrated circuit that processes a biological signal obtained from a living body to generate biological signal data, a switch SW that activates the biological sensor 1, a flash memory that stores biological signals, and various components mounted on the flexible substrate 31 such as a light emitting element, and obtains biological information. In addition, examples of circuits including various components are omitted. The component mounting section 321 operates by power supplied by the battery 34 installed in the battery installation section 322.

[0134] The component mounting unit 321 transmits the information to an external device such as an operation confirmation device that confirms the initial operation or a reading device that reads the biological information from the biosensor 1 by wire or wirelessly.

[0135] The battery mounting portion 322 is disposed between the connection portion 33A and the component mounting portion 321, and supplies power to the integrated circuit and the like mounted on the component mounting portion 321. Figure 2 As shown, a battery 34 is installed.

[0136] The connecting parts 33A and 33B have: wirings 331A and 331B respectively connected to the sensor body 32 in the length direction (Y-axis direction) of the sensor body 32, and terminal parts 332A and 332B arranged on the front end side of the wirings 331A and 331B and connected to the electrode 20.

[0137] One end of the wiring 331A and 331B is as follows Figure 3 As shown, each is connected to an electrode 20 . Figure 3 As shown, the other end of the wiring 331A is connected to the switch SW etc. mounted on the component mounting portion 321 along the outer circumference of the sensor body 32. The other end of the wiring 331B is connected to the switch SW etc. mounted on the component mounting portion 321.

[0138] The terminals 332A and 332B are connected to the wirings 331A and 331B at one end and are arranged in a state of being sandwiched between the first layer member 10 and the second layer member 40 while the top surfaces of the other ends are in contact with the electrode 20 .

[0139] A known battery can be used as the battery 34. As the battery 34, for example, a button-type battery such as CR2025 can be used.

[0140] [Layer 2 components]

[0141] Figure 3As shown, the second layer member 40 is provided on the attachment surface side of the electrode 20 and the sensor section 30 , is a support substrate on which the sensor section 30 is provided, and forms a part of the attachment surface to the skin 2 . Figure 1 and Figure 2 As shown, the outer shape of both sides of the width direction (X-axis direction) of the second layer member 40 can be substantially the same as the outer shape of both sides of the width direction (X-axis direction) of the first layer member 10. The length (Y-axis direction) of the second layer member 40 is formed shorter than the length (Y-axis direction) of the covering member 11 and the upper sheet 12. Figure 3 As shown, both ends of the second layer member 40 in the longitudinal direction are located so as to sandwich the wirings 331A and 331B of the sensor unit 30 between the second layer member 40 and the upper sheet 12 , that is, to overlap with a part of the electrode 20 .

[0142] The second layer member 40 includes a second base material 41, a lower adhesive layer 42 provided on the upper surface of the second base material 41, and a second adhesive layer 43 provided on the lower surface of the second base material 41. The second base material 41, the lower adhesive layer 42, and the second adhesive layer 43 may be formed in the same shape when viewed from above. The second adhesive layer 43 of the second layer member 40 and the electrode 20 form an adhesive surface for the skin 2. The waterproofness and moisture permeability are different according to the area of ​​the electrode 20 and the second adhesive layer 43, and the adhesiveness can be made different. Thus, the waterproofness and moisture permeability can be made different according to the area of ​​the adhesive surface of the second adhesive layer 43, and the adhesiveness can be made different.

[0143] (Second base material)

[0144] The second base material 41 can be formed using a flexible resin having appropriate stretchability, flexibility, and toughness. As the material forming the second substrate 41, for example, polyester resins such as polyethylene terephthalate (PET), polybutylene terephthalate, polyethylene terephthalate, polyethylene naphthalate, and polybutylene naphthalate; acrylic resins such as polyacrylic acid, polymethacrylic acid, polymethyl acrylate, polymethyl methacrylate (PMMA), polyethyl methacrylate, and polybutyl acrylate; polyolefin resins such as polyethylene and polypropylene; polystyrene resins such as polystyrene, imide-modified polystyrene, acrylonitrile-butadiene-styrene (ABS) resin, imide-modified ABS resin, styrene-acrylonitrile copolymer (SAN) resin, and acrylonitrile-ethylene-propylene-diene-styrene (AES) resin; polyimide resin; polyurethane resin; silicone resin; polyvinyl chloride resins such as polyvinyl chloride and ethylene-vinyl acetate copolymer resin, and the like can be used. Among these, polyolefin resins and PET are preferably used. These thermoplastic resins have water-repellent properties (low water permeability) that prevent water and water vapor from penetrating. Therefore, the second substrate 41 is formed using these thermoplastic resins, so that sweat or water vapor generated by the skin 2 of the living body can be prevented from passing through the second substrate 41 and invading the flexible substrate 31 side of the sensor unit 30 when the biosensor 1 is attached to the skin 2 of the living body.

[0145] The second base material 41 is preferably formed in a flat plate shape because the sensor section 30 is provided on the upper surface thereof via the lower adhesive layer 42 .

[0146] The thickness of the second substrate 41 can be appropriately and arbitrarily selected, and can be, for example, 1 μm to 300 μm.

[0147] (Adhesive layer at the bottom)

[0148] Figure 3 As shown, the lower adhesive layer 42 is arranged on the upper side of the covering member 11 side (+Z axial direction) of the second substrate 41, and the sensor part 30 is bonded. The two end sides of the lower adhesive layer 42 of the second layer member 40 in the length direction are arranged at positions opposite to the opposing parts 201A and 201B of the electrode 20. As a result, the opposing parts 201A and 201B of the electrode 20 can be sandwiched between the upper sheet 12 and the second layer member 40 in a state where the terminal parts 332A and 332B are pushed, and the electrode 20 can be connected to the terminal parts 332A and 332B. The lower adhesive layer 42 can use the same material as the second adhesive layer 43 described later, so the details are omitted. In addition, the lower adhesive layer 42 does not need to be provided and can be omitted.

[0149] (Second adhesive layer)

[0150] Figure 3 As shown, the second adhesive layer 43 is provided on the lower surface of the sticking side (-Z axis direction) of the second base material 41 and is a layer in contact with the living body.

[0151] The second adhesive layer 43 preferably has pressure-sensitive adhesiveness. Since the second adhesive layer 43 has pressure-sensitive adhesiveness, the biosensor 1 can be easily attached to the skin 2 by being pressed against the skin 2 of a living body.

[0152] The material of the second adhesive layer 43 is not particularly limited as long as it is a material having pressure-sensitive adhesive properties, and materials having biocompatibility can be cited. As the material forming the second adhesive layer 43, acrylic pressure-sensitive adhesives, silicone pressure-sensitive adhesives, etc. can be cited. Preferably, acrylic pressure-sensitive adhesives can be cited.

[0153] 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. As the acrylic polymer, a polymer obtained by polymerizing a (meth)acrylate containing isononyl acrylate, methoxyethyl acrylate, etc. as a main component and a monomer copolymerizable with a (meth)acrylate such as acrylic acid as an arbitrary component can be used.

[0154] The acrylic pressure-sensitive adhesive preferably further contains a carboxylate. The carboxylate acts as a pressure-sensitive adhesive force regulator that reduces the pressure-sensitive adhesive force of the acrylic polymer and adjusts the pressure-sensitive adhesive force of the second adhesive layer 43. The carboxylate can be a carboxylate that is compatible with the acrylic polymer. As the carboxylate, triglycerides and the like can be used.

[0155] Acrylic pressure-sensitive adhesive can contain a cross-linking agent as required. The cross-linking agent is a cross-linking component that cross-links an acrylic polymer. As the cross-linking agent, polyisocyanate compounds (multifunctional isocyanate compounds), epoxy compounds, melamine compounds, peroxide compounds, urea compounds, metal alkoxide compounds, metal chelates, metal salt compounds, carbodiimide compounds, oxazoline compounds, aziridine compounds, amine compounds, etc. can be cited. Among these, polyisocyanate compounds are preferably used. These cross-linking agents can be used alone or in combination.

[0156] The second adhesive layer 43 preferably has excellent biocompatibility. For example, when the second adhesive layer 43 is subjected to a keratin peeling test, the keratin peeling area ratio is preferably 0% to 50%. If the keratin peeling area ratio is within the range of 0% to 50%, even if the second adhesive layer 43 is attached to the skin 2, the load on the skin 2 can be suppressed.

[0157] The second adhesive layer 43 preferably has moisture permeability. Water vapor and the like generated by the skin 2 to which the biosensor 1 is attached can escape to the upper sheet 12 side through the second adhesive layer 43. In addition, as described later, the upper sheet 12 has a bubble structure, so that water vapor can be released to the outside of the biosensor 1 through the second adhesive layer 43. As a result, it is possible to suppress the retention of sweat or water vapor at the interface between the skin 2 to which the biosensor 1 is attached and the second adhesive layer 43. As a result, the moisture accumulated at the interface between the skin 2 and the second adhesive layer 43 weakens the adhesive force of the second adhesive layer 43, and it is possible to suppress the biosensor 1 from peeling off from the skin.

[0158] The moisture permeability of the second adhesive layer 43 is preferably, for example, 300 g / (m 2 ·day)~10000g / (m 2 If the moisture permeability of the second adhesive layer 43 is within the above-mentioned preferred range, even when the second adhesive layer 43 is attached to the skin 2, sweat generated from the skin 2 can be appropriately transmitted from the second adhesive layer 43 to the outside, thereby reducing the burden on the skin 2.

[0159] The thickness of the second adhesive layer 43 can be appropriately selected, but is preferably 10 μm to 300 μm. When the thickness of the second adhesive layer 43 is 10 μm to 300 μm, the biosensor 1 can be made thinner.

[0160] Figure 1 and Figure 2 As shown in the figure, when the biosensor 1 is not in use, the electrode 20 and the second layer member 40 are protected on the biosensor's attachment surface between the electrode 20 and the second substrate 41. Therefore, it is preferable to attach a release liner 50 until use. When in use, the release liner 50 is peeled off from the electrode 20 and the second layer member 40, and the attachment surface of the biosensor 1 is attached to the skin 2. By attaching the release liner 50 to the attachment surface, the adhesion between the electrode 20 and the second layer member 40 can be maintained even if the biosensor 1 is stored for a long time. Therefore, by peeling the release liner 50 from the second layer member 40 and the electrode 20 when in use, the attachment surface can be securely attached to the skin 2 for use.

[0161] The method for producing the biosensor 1 is not particularly limited, and the biosensor 1 can be produced using any appropriate method. An example of a method for producing the biosensor 1 will be described.

[0162] Prepare Figure 1 and Figure 2 The first layer member 10, the electrode 20, the sensor portion 30 and the second layer member 40 are shown. The first layer member 10, the electrode 20, the sensor portion 30 and the second layer member 40 are not particularly limited as long as the method for manufacturing them can be used, and can be manufactured using any appropriate manufacturing method.

[0163] Prepare to pose Figure 1 After the first layer member 10, the electrode 20, the sensor portion 30 and the second layer member 40 of the biosensor 1 shown in the figure are stacked, the sensor portion 30 is placed on the second layer member 40. Then, from the first layer member 10 side toward the second layer member 40 side, the first layer member 10, the electrode 20, the sensor portion 30 and the second layer member 40 are stacked in order. Thus, a Figure 1 The biosensor 1 is shown.

[0164] Figure 5 To express that Figure 1 1 is an explanatory diagram showing a state where the biosensor 1 is attached to the chest of a subject P. Figure 5 As shown, for example, the biosensor 1 is placed on the sternum of the subject P in the longitudinal direction (Y-axis direction), with one electrode 20 on the upper side and the other electrode 20 on the lower side, and is attached to the skin of the subject P. The biosensor 1 is formed by using Figure 2 The second adhesive layer 43 is adhered to the skin of the subject P, so that the electrode 20 is pressed against the skin of the subject P, and a biological signal such as an electrocardiogram signal is obtained from the subject P through the electrode 20. The biosensor 1 stores the obtained biological signal data in a non-volatile memory such as a flash memory mounted on the component mounting portion 321.

[0165] Thus, the biosensor 1 includes the first layer member 10, the electrode 20, the sensor body 32, and the second layer member 40. The electrode 20 has a thickness of 15 μm or more and an area of ​​2.0 cm 2 ~5.0cm 2 , the adhesive force is 60gf / Ф5mm or more. As a result, the electrode 20 can have appropriate softness, and the elongation of the biosensor 1 in the longitudinal direction is easy to extend, so the adhesion of the biosensor 1 to the surface of the skin 2 can be improved. Moreover, when the biosensor 1 is viewed from its bottom surface, the occupancy rate of the electrode 20 in the first layer member 10 is 40% to 90%. As a result, the contact impedance of the biosensor 1 can be reduced, thereby suppressing the generation of noise. As a result, the biosensor 1 can suppress the generation of noise during use and can be stably attached to the biological body.

[0166] Therefore, the biosensor 1 can improve the accuracy of the electrocardiogram waveform measured as a biosignal during electrocardiogram measurement and improve the adhesion to the surface of the skin 2 .

[0167] In the biosensor 1, the first layer member 10 includes the first substrate 121 and the first adhesive layer 122, and the electrode 20 can be attached to the lower surface of the second layer member 40 side as the first adhesive layer 122. The first adhesive layer 122 has adhesiveness, so the electrode 20 can contact the surface of the skin 2 in a state where the first adhesive layer 122 is stably attached to the first layer member 10, thereby further reducing the contact impedance between the electrode 20 and the surface of the skin 2, and further suppressing the generation of noise. As a result, the biosensor 1 can stably suppress the generation of noise during use and stably maintain the adhesiveness to the living body.

[0168] The biosensor 1 can have a second adhesive layer 43 on the surface of the second layer member 40 on the opposite side to the first layer member 10 side. Thus, the biosensor 1 can adhere the second layer member 40 to the skin 2 via the second adhesive layer 43, thereby further reducing the contact impedance between the electrode 20 and the surface of the skin 2, and further suppressing the generation of noise. Thus, the biosensor 1 can stably suppress the generation of noise during use and stably maintain the adhesion to the living body.

[0169] The biosensor 1 can form a bonding surface to the skin 2 by the first layer member 10, the electrode 20 and the second layer member 40. Thus, the thickness of the biosensor 1 can be reduced. Thus, the biosensor 1 can be made smaller and have lower contact impedance with the surface of the skin 2.

[0170] In the biosensor 1, the electrode 20 can have adhesiveness. The electrode 20 has adhesiveness, so that even if the first layer member 10 is not provided with the first adhesive layer 122, it can be attached to the lower surface of the first layer member 10. Therefore, the thickness of the biosensor 1 can be reduced. In addition, the electrode 20 can be adhered to the skin 2, so that the adhesion with the skin 2 can be maintained. Therefore, the biosensor 1 can be more compact and further effectively reduce the contact impedance with the surface of the skin 2.

[0171] Furthermore, in the biosensor 1, since the electrode 20 has adhesiveness, it is not necessary to provide the first adhesive layer 122 on the first layer member 10, and the biosensor 1 can be made small. Therefore, the biosensor 1 can reduce the manufacturing cost.

[0172] Furthermore, in the biosensor 1, the electrode 20 has adhesiveness and can adhere to the upper surface of the second layer member 40, thereby reducing the contact resistance between the electrode 20 and the second layer member 40. Therefore, the biosensor 1 can detect the biological signal obtained from the skin 2 more stably.

[0173] In the biosensor 1, the electrode 20 includes a conductive polymer, a binder resin, and a moisturizer, and the binder resin can be composed of an aqueous emulsion adhesive. As a result, the electrode 20 can reduce resistance, improve viscoelasticity, and suppress swelling caused by water absorption. Therefore, the electrode 20 can improve water resistance, thereby exerting conductivity and adhesiveness, and can improve flexibility and improve followability to the surface of the skin 2. As a result, in the biosensor 1, the electrode 20 can maintain adhesiveness to the skin 2, so that the contact impedance with the surface of the skin 2 can be more reliably reduced.

[0174] In the biosensor 1, an acrylic emulsion adhesive can be used as the water-based emulsion adhesive of the electrode 20. As a result, the water resistance of the electrode 20 is surely improved, thereby suppressing the decrease in adhesive force while maintaining the resistance, and surely improving the followability to the surface of the skin 2. Therefore, the electrode 20 can surely suppress the viscoelasticity to be low, and thus can have high adhesive force and followability to the surface of the skin 2. As a result, the biosensor 1 can surely reduce the contact impedance with the surface of the skin 2.

[0175] In the biosensor 1, as the acrylic emulsion adhesive of the electrode 20, a silane emulsion adhesive containing: a monomer mixture containing an alkyl (meth)acrylate, a water-dispersible copolymer obtained by copolymerizing a silane monomer copolymerizable with the alkyl (meth)acrylate, and an organic liquid component compatible with the water-dispersible copolymer can be used. As a result, the electrode 20 can reliably suppress the viscoelasticity to a low level, thereby improving the adhesive force and further improving the followability to the surface of the skin 2. As a result, the biosensor 1 can further reliably reduce the contact impedance with the surface of the skin 2.

[0176] In the biosensor 1, as the acrylic emulsion adhesive of the electrode 20, a two-component or three-component acrylic emulsion adhesive containing one or more components selected from the group consisting of a monomer mixture containing an alkyl (meth)acrylate and a monomer mixture containing a carboxyl group can be used. In this case, the electrode 20 can surely suppress the viscoelasticity to a low level, thereby increasing the adhesive force and further improving the followability to the surface of the skin 2. As a result, the biosensor 1 can further surely reduce the contact impedance with the surface of the skin 2.

[0177] Thus, the biosensor 1 can stably measure the biometric information from the skin 2 for a long time during use as described above, and can be effectively used as a stick-on biosensor that is stuck to the human skin 2. The biosensor 1 can be stuck to the skin of a living body, for example, and is suitable for use in a wearable device for health that requires high sensitivity in detecting electrocardiograms and high suppression effect of noise generated by electrocardiograms.

[0178] As described above, the embodiments are described, but the above embodiments are provided as examples, and the present invention is not limited by the above embodiments. The above embodiments can be implemented in various other forms, and various combinations, omissions, substitutions, changes, etc. can be made within the scope of the subject matter of the invention. These embodiments and their variations are included in the scope and subject matter of the invention, and are included in the invention described in the claims and their equivalents.

[0179] Example

[0180] Hereinafter, the embodiment will be described in more detail with reference to Examples and Comparative Examples, but the embodiment is not limited to these Examples and Comparative Examples.

[0181] <Example 1>

[0182] [Electrode preparation]

[0183] (Fabrication of Electrode 1)

[0184] 0.8 g of PEDOT / PSS particles (Orgacon DRY, manufactured by AGFA Materials, Japan) as a conductive polymer, 3.25 g of a silane emulsion adhesive (manufactured by Nitto Denko) as a binder resin, and 1.6 g of glycerin (manufactured by Wako Pure Chemical Industries, Ltd.) as a moisturizer were added to a plastic container, and stirred and degassed using a planetary stirring device to prepare a uniform adhesive electrode-forming composition. The adhesive electrode-forming composition was taken out and cured to produce a cured product of an adhesive conductive composition. The cured product was punched (pressed) into a desired shape and formed into a sheet to produce an electrode 1 as an adhesive electrode sheet (biological electrode). The thickness of the electrode 1 was 30 μm.

[0185] (Fabrication of Electrode 2)

[0186] 1. Preparation of Conductive Composition

[0187] 0.38 parts by mass of PEDOT / PSS particles (Orgacon DRY, manufactured by AGFA Materials, Japan) as a conductive polymer, 10.00 parts by mass of an aqueous solution containing modified polyvinyl alcohol (modified PVA) as a binder resin (modified polyvinyl alcohol concentration: 10%, gohsenx Z-410, manufactured by Nippon Synthetic Chemical Co., Ltd.), 2.00 parts by mass of glycerol (manufactured by Wako Pure Chemical Industries, Ltd.) as a plasticizer, 1.60 parts by mass of 2-propylene glycol as a solvent, and 6.50 parts by mass of water were added to an ultrasonic bath. The aqueous solution containing these components was mixed in an ultrasonic bath for 30 minutes to prepare a uniform conductive composition aqueous solution A.

[0188] Since the concentration of the modified PVA in the aqueous solution containing the modified PVA was about 10%, the content of the modified PVA in the conductive composition aqueous solution A was 1.00 parts by mass.

[0189] The contents of the conductive polymer, the binder resin, and the plasticizer were 11.2 parts by mass, 29.6 parts by mass, and 59.2 parts by mass, respectively, relative to 100.0 parts by mass of the conductive composition.

[0190] 2. Preparation of electrode sheets

[0191] The prepared conductive composition aqueous solution A was applied to a polyethylene terephthalate (PET) film using an applicator. The PET film coated with the conductive composition aqueous solution A was then transported to a drying oven (SPHH-201, manufactured by ESPEC), and the conductive composition aqueous solution A was heated and dried at 135° C. for 3 minutes to produce a solidified conductive composition. The solidified material was punched (pressed) into a desired shape and formed into a sheet to produce an electrode 2 as an electrode sheet (biological electrode) having a thickness of 20 μm.

[0192] The contents of the conductive polymer, the binder resin, and the plasticizer contained in the electrode 2 are 11.2 parts by mass, 29.6 parts by mass, and 59.2 parts by mass, respectively, similar to those in the conductive composition.

[0193] [Adhesion of electrodes]

[0194] The adhesion of the electrode was measured using a wrinkle tester (Tackiness Tester TAC1000, manufactured by Leska). As the measurement conditions, the pressing load for the electrode was 50 gf, the pressing speed was 0.01 mm / s, the holding time was 1.0 s, and the pulling speed was 1 mm / s. The results of the measurement of the adhesion of the electrode are shown in Table 1.

[0195] [Production of biosensors]

[0196] (Production of Covering Member)

[0197] A coating layer having a Shore hardness of A40 made of silicone rubber was formed on a support formed using PET as a base resin, and then molded into a predetermined shape to produce a covering member.

[0198] (Preparation of the first layer laminate)

[0199] A double-sided adhesive tape 1 (PKE-20, manufactured by Nitto Denko Corporation, thickness: 60 μm) was adhered to the bottom of the first substrate (polyolefin foam sheet (FOLEC (registered trademark), manufactured by INOAC CORPORATION, thickness: 0.5 mm) formed in a rectangular shape as a porous substrate to form a first adhesive layer. In addition, the double-sided adhesive tape 1 is a double-sided adhesive tape having an adhesive (acrylic resin) formed on its surface. Then, a silicone tape (ST503 (HC) 60, manufactured by Nitto Denko Corporation, thickness: 60 μm) was adhered to the adhesive layer to form an upper adhesive layer, thereby producing a first laminated sheet.

[0200] (Production of the second layer laminate)

[0201] Adhesives (permeroll, manufactured by Nitto Denko Corporation, moisture permeability: 21 g / (m 2 ·day)), forming the lower adhesive layer and the second adhesive layer to produce the second layer laminate.

[0202] (Production of Biosensors)

[0203] A sensor unit having a battery and a control unit is provided in the central portion of the upper surface of the second laminate. Then, an adhesive electrode as a pair of electrodes 1 is attached to the adhesive surface side of the first adhesive layer in a state of being sandwiched between the first adhesive layer of the first laminate and the second laminate, and the electrodes 1 are connected to the wiring of the sensor unit. Then, a covering member is stacked on the first laminate so that the sensor unit is arranged in a receiving space formed by the first laminate and the covering member, thereby manufacturing a biological sensor.

[0204] (Adhesive force of the first adhesive layer)

[0205] After the inner lining tape is attached to one side of the adhesive, a sample piece (width 10 mm × length 50 mm) is cut out from the adhesive sheet with the inner lining tape. Next, a laminator is used to attach the adhesive side of the sample piece to a resin plate (phenolic resin plate). In addition, a tensile testing machine (automatic plotter AGS-50NX, manufactured by Shimadzu Corporation) is used to perform a peeling test of the inner lining tape of the sample piece on the stretched resin plate at 23°C, a peeling angle of 180°, and a peeling speed of 300 mm / min, and the peeling adhesion (peeling force) of the adhesive sheet relative to the resin plate at 23°C is measured (unit: N / 10mm).

[0206] (Area of ​​the first adhesive layer)

[0207] The bottom surface of the manufactured biosensor is photographed, and the image of the bottom surface of the first adhesive layer in the image of the bottom surface of the biosensor is binarized using image analysis software (ImageJ) to calculate the area S1 of the first adhesive layer represented by the dot (pixel) unit.

[0208] (Area of ​​electrode)

[0209] The bottom surface of the manufactured biosensor is photographed, and the image of the bottom surface of the electrode in the image of the bottom surface of the biosensor is binarized using image analysis software (ImageJ) to calculate the area S2 of the electrode represented by the dot (pixel) unit.

[0210] (Electrode occupancy)

[0211] The electrode occupancy rate is determined by the following formula (1) using the area S1 of the first adhesive layer and the area S2 of the electrode determined as described above.

[0212] Electrode occupancy (%) = Area S2 / (Area S1+Area S2)×100···(1)

[0213] Table 1 shows the measurement results of the area of ​​the first adhesive layer, the area of ​​the electrode, the electrode occupancy rate, and the adhesive force.

[0214] <Example 2>

[0215] In Example 1, a double-sided adhesive tape 2 (H-PAO, manufactured by Nitto Denko Corporation, thickness: 60 μm) is used as the first adhesive layer instead of the double-sided adhesive tape 1, and the area S1 of the first adhesive layer on one side and the area S2 and occupancy rate of the electrode on one side are changed as shown in Table 1. Except for this, the same procedure as in Example 1 is carried out to produce a biological sensor.

[0216] <Comparative Example 1>

[0217] In Example 1, except that the electrode 1 was changed to the electrode 2 and the area S1 of the first adhesive layer and the area S2 of the electrode and the occupancy rate were changed as shown in Table 1, the same procedure as in Example 1 was followed to produce a biological sensor.

[0218] <Comparative Example 2>

[0219] In Example 1, double-sided adhesive tape 2 (PH-PAO, manufactured by Nitto Denko Corporation, thickness: 60 μm) was used as the first adhesive layer instead of double-sided adhesive tape 1, electrode 1 was changed to electrode 2, and the area S1 of the first adhesive layer on one side and the area S2 of the electrode on one side and the occupancy rate were changed as shown in Table 1. Except for this, the same method as in Example 1 was carried out to produce a biological sensor.

[0220] Table 1 shows the measurement results of the area of ​​the first adhesive layer, the area of ​​the electrode, the occupancy rate of the electrode, and the adhesive force of each of the above-mentioned Examples and Comparative Examples.

[0221] <Evaluation of biosensor characteristics>

[0222] The waveform accuracy and adhesion of the biosensors of the respective examples and comparative examples were measured and evaluated.

[0223] [Waveform accuracy]

[0224] The waveform accuracy of the biosensor is evaluated based on the following evaluation criteria: the biosensor is attached to a subject for 24 hours and the contact impedance is measured when an electrocardiogram is measured. If the contact impedance is 400 kΩ or less, the biosensor can be effectively used for electrocardiogram measurement.

[0225] (Evaluation Criteria)

[0226] A: The contact resistance is 400kΩ or less.

[0227] B: Contact resistance exceeds 400kΩ.

[0228] [Adhesion]

[0229] The adhesion of the biosensor was evaluated based on the following evaluation criteria when the biosensor was attached to a subject for 24 hours and an electrocardiogram was measured.

[0230] (Evaluation Criteria)

[0231] A: The biosensor remains attached to the subject's skin.

[0232] B: At least a portion of the biosensor is peeled off from the subject's skin.

[0233] [Table 1]

[0234]

[0235] Table 1 shows that the waveform accuracy and adhesiveness of the biosensors in Examples 1 and 2 satisfy the use conditions. In contrast, it is shown that at least one of the waveform accuracy and adhesiveness of the biosensors in Comparative Examples 1 and 2 does not satisfy the use conditions.

[0236] Therefore, if the thickness, area and adhesive force of the electrodes of the biosensors of the above-mentioned embodiments are respectively set to be below the predetermined values, the noise generated by the electrocardiogram during the measurement of the electrocardiogram can be suppressed to stably obtain the electrocardiogram waveform, and the biosensor can be stably attached to the skin of the subject to maintain the adhesiveness. Therefore, it can be said that even if the biosensor involved in this embodiment is attached to the skin of the subject for a long time (for example, 24 hours), it can be effectively used to measure the electrocardiogram continuously for a long time.

[0237] In addition, the embodiments of the present invention are as follows, for example.

[0238] <1> A biosensor comprising: a sensor body for acquiring biometric information;

[0239] An adhesive electrode connected to the sensor body,

[0240] The electrode is provided below, and a first layer member has a storage space for storing the sensor body, and

[0241] A second layer member is attached to the lower surface of the first layer member so as to expose the electrode and cover the sensor body.

[0242] The thickness of the electrode is 15 μm or more, and the area of ​​the electrode is 2.0 cm 2 ~5.0cm 2 , the adhesion of the above-mentioned electrode is 60gf / Ф5mm or more,

[0243] The occupancy rate of the electrode in the first layer member is 40% to 90% when viewed from the bottom.

[0244] <2> The biosensor according to <1>, wherein the first layer member comprises:

[0245] a first substrate having a through hole at a position corresponding to the storage space, and

[0246] The first adhesive layer having the electrode attached thereto is provided on the surface of the first substrate on the biological body side.

[0247] The electrode is attached to the second layer member side of the first adhesive layer.

[0248] <3> The biosensor according to <1> or <2>, wherein the second layer member has a second adhesive layer on a surface opposite to the first layer member.

[0249] <4> The biosensor according to any one of <1> to <3>, wherein an adhesive surface for a living body is formed by the first layer member, the electrode, and the second layer member.

[0250] This application claims the priority based on Japanese Patent Application No. 2022-090963 filed with the Japan Patent Office on June 3, 2022, and cites all the contents described in the above application.

[0251] Explanation of symbols

[0252] 1 Biosensor

[0253] 2 Skin

[0254] 101st layer components

[0255] 11 Covering components

[0256] 12 Upper piece

[0257] 12a, 121a, 122a through holes

[0258] 20, 20A, 20B electrodes

[0259] 30 Sensor unit

[0260] 31 Flexible Substrate

[0261] 32 Sensor body

[0262] 33A Connection

[0263] 33A, 33B connection part

[0264] 34 Batteries

[0265] 40 Layer 2 Components

[0266] 41 2nd base material

[0267] 42 Adhesive layer for the lower part

[0268] 43 Second adhesive layer

[0269] 111 Protrusion

[0270] 111a Pit

[0271] 112A, 112B flat part

[0272] 121 No.1 Base Material

[0273] 1221st adhesive layer

[0274] 123 Adhesive layer for upper part

[0275] 201A, 201B opposing parts

[0276] 202A, 201B exposed parts

[0277] 321 Component mounting area

[0278] 322 Battery Installation Department

[0279] 331A, 331B wiring

[0280] 332A, 332B terminal part

Claims

1. A biosensor comprising: The sensor body that acquires biological information, an adhesive electrode connected to the sensor body, The electrode is disposed below, and a first layer member has a storage space for storing the sensor body, and a second layer member attached to the lower surface of the first layer member so as to expose the electrode and cover the sensor body; The thickness of the electrode is greater than 15 μm, and the area of ​​the electrode is 2.0 cm 2 ~5.0cm 2 , the adhesion of the electrode is 60gf / Ф5mm or more, When viewed from the bottom, the occupancy rate of the electrode in the first layer member is 40% to 90%.

2. The biosensor according to claim 1, The first layer component comprises: a first substrate having a through hole at a position corresponding to the storage space, and The first adhesive layer of the electrode is attached to the surface of the first substrate on the biological body side. The electrode is attached to the second layer member side of the first adhesive layer.

3. The biosensor according to claim 1, The second layer member has a second adhesive layer on a surface opposite to the first layer member.

4. The biosensor according to any one of claims 1 to 3, The first layer member, the electrodes, and the second layer member form an adhesive surface for a living body.

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